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Sample records for pretreatment process involves

  1. Temperature Modelling of the Biomass Pretreatment Process

    DEFF Research Database (Denmark)

    Prunescu, Remus Mihail; Blanke, Mogens; Jensen, Jakob M.

    2012-01-01

    In a second generation biorefinery, the biomass pretreatment stage has an important contribution to the efficiency of the downstream processing units involved in biofuel production. Most of the pretreatment process occurs in a large pressurized thermal reactor that presents an irregular temperature...... that captures the environmental temperature differences inside the reactor using distributed parameters. A Kalman filter is then added to account for any missing dynamics and the overall model is embedded into a temperature soft sensor. The operator of the plant will be able to observe the temperature in any...

  2. Processes for pretreating lignocellulosic biomass: A review

    Energy Technology Data Exchange (ETDEWEB)

    McMillan, J.D.

    1992-11-01

    This paper reviews existing and proposed pretreatment processes for biomass. The focus is on the mechanisms by which the various pretreatments act and the influence of biomass structure and composition on the efficacy of particular pretreatment techniques. This analysis is used to identify pretreatment technologies and issues that warrant further research.

  3. Evaluation of high-level waste pretreatment processes with an approximate reasoning model

    International Nuclear Information System (INIS)

    Bott, T.F.; Eisenhawer, S.W.; Agnew, S.F.

    1999-01-01

    The development of an approximate-reasoning (AR)-based model to analyze pretreatment options for high-level waste is presented. AR methods are used to emulate the processes used by experts in arriving at a judgment. In this paper, the authors first consider two specific issues in applying AR to the analysis of pretreatment options. They examine how to combine quantitative and qualitative evidence to infer the acceptability of a process result using the example of cesium content in low-level waste. They then demonstrate the use of simple physical models to structure expert elicitation and to produce inferences consistent with a problem involving waste particle size effects

  4. Techno-economic analysis of organosolv pretreatment process from lignocellulosic biomass

    DEFF Research Database (Denmark)

    Rodrigues Gurgel da Silva, Andrè; Errico, Massimiliano; Rong, Ben-Guang

    2018-01-01

    data, we propose a feasible process flowsheet for organosolv pretreatment. Simulation of the pretreatment process provided mass and energy balances for a techno-economic analysis, and the values were compared with the most prevalent and mature pretreatment method: diluted acid. Organosolv pretreatment...... required more energy, 578.1 versus 213.8 MW for diluted acid pretreatment, but resulted in a higher ethanol concentration after the biomass fermentation, 11.1% compared to 5.4%. Total annual costs (TACs) calculations showed advantages for diluted acid pretreatment, but future improvements explored...

  5. Lignocellulosic Biomass Transformations via Greener Oxidative Pretreatment Processes: Access to Energy and Value-Added Chemicals.

    Science.gov (United States)

    Den, Walter; Sharma, Virender K; Lee, Mengshan; Nadadur, Govind; Varma, Rajender S

    2018-01-01

    Anthropogenic climate change, principally induced by the large volume of carbon dioxide emission from the global economy driven by fossil fuels, has been observed and scientifically proven as a major threat to civilization. Meanwhile, fossil fuel depletion has been identified as a future challenge. Lignocellulosic biomass in the form of organic residues appears to be the most promising option as renewable feedstock for the generation of energy and platform chemicals. As of today, relatively little bioenergy comes from lignocellulosic biomass as compared to feedstock such as starch and sugarcane, primarily due to high cost of production involving pretreatment steps required to fragment biomass components via disruption of the natural recalcitrant structure of these rigid polymers; low efficiency of enzymatic hydrolysis of refractory feedstock presents a major challenge. The valorization of lignin and cellulose into energy products or chemical products is contingent on the effectiveness of selective depolymerization of the pretreatment regime which typically involve harsh pyrolytic and solvothermal processes assisted by corrosive acids or alkaline reagents. These unselective methods decompose lignin into many products that may not be energetically or chemically valuable, or even biologically inhibitory. Exploring milder, selective and greener processes, therefore, has become a critical subject of study for the valorization of these materials in the last decade. Efficient alternative activation processes such as microwave- and ultrasound irradiation are being explored as replacements for pyrolysis and hydrothermolysis, while milder options such as advanced oxidative and catalytic processes should be considered as choices to harsher acid and alkaline processes. Herein, we critically abridge the research on chemical oxidative techniques for the pretreatment of lignocellulosics with the explicit aim to rationalize the objectives of the biomass pretreatment step and the

  6. Lignocellulosic Biomass Transformations via Greener Oxidative Pretreatment Processes: Access to Energy and Value-Added Chemicals

    Directory of Open Access Journals (Sweden)

    Walter Den

    2018-04-01

    Full Text Available Anthropogenic climate change, principally induced by the large volume of carbon dioxide emission from the global economy driven by fossil fuels, has been observed and scientifically proven as a major threat to civilization. Meanwhile, fossil fuel depletion has been identified as a future challenge. Lignocellulosic biomass in the form of organic residues appears to be the most promising option as renewable feedstock for the generation of energy and platform chemicals. As of today, relatively little bioenergy comes from lignocellulosic biomass as compared to feedstock such as starch and sugarcane, primarily due to high cost of production involving pretreatment steps required to fragment biomass components via disruption of the natural recalcitrant structure of these rigid polymers; low efficiency of enzymatic hydrolysis of refractory feedstock presents a major challenge. The valorization of lignin and cellulose into energy products or chemical products is contingent on the effectiveness of selective depolymerization of the pretreatment regime which typically involve harsh pyrolytic and solvothermal processes assisted by corrosive acids or alkaline reagents. These unselective methods decompose lignin into many products that may not be energetically or chemically valuable, or even biologically inhibitory. Exploring milder, selective and greener processes, therefore, has become a critical subject of study for the valorization of these materials in the last decade. Efficient alternative activation processes such as microwave- and ultrasound irradiation are being explored as replacements for pyrolysis and hydrothermolysis, while milder options such as advanced oxidative and catalytic processes should be considered as choices to harsher acid and alkaline processes. Herein, we critically abridge the research on chemical oxidative techniques for the pretreatment of lignocellulosics with the explicit aim to rationalize the objectives of the biomass

  7. Lignocellulosic Biomass Transformations via Greener Oxidative Pretreatment Processes: Access to Energy and Value-Added Chemicals

    Science.gov (United States)

    Den, Walter; Sharma, Virender K.; Lee, Mengshan; Nadadur, Govind; Varma, Rajender S.

    2018-01-01

    Anthropogenic climate change, principally induced by the large volume of carbon dioxide emission from the global economy driven by fossil fuels, has been observed and scientifically proven as a major threat to civilization. Meanwhile, fossil fuel depletion has been identified as a future challenge. Lignocellulosic biomass in the form of organic residues appears to be the most promising option as renewable feedstock for the generation of energy and platform chemicals. As of today, relatively little bioenergy comes from lignocellulosic biomass as compared to feedstock such as starch and sugarcane, primarily due to high cost of production involving pretreatment steps required to fragment biomass components via disruption of the natural recalcitrant structure of these rigid polymers; low efficiency of enzymatic hydrolysis of refractory feedstock presents a major challenge. The valorization of lignin and cellulose into energy products or chemical products is contingent on the effectiveness of selective depolymerization of the pretreatment regime which typically involve harsh pyrolytic and solvothermal processes assisted by corrosive acids or alkaline reagents. These unselective methods decompose lignin into many products that may not be energetically or chemically valuable, or even biologically inhibitory. Exploring milder, selective and greener processes, therefore, has become a critical subject of study for the valorization of these materials in the last decade. Efficient alternative activation processes such as microwave- and ultrasound irradiation are being explored as replacements for pyrolysis and hydrothermolysis, while milder options such as advanced oxidative and catalytic processes should be considered as choices to harsher acid and alkaline processes. Herein, we critically abridge the research on chemical oxidative techniques for the pretreatment of lignocellulosics with the explicit aim to rationalize the objectives of the biomass pretreatment step and the

  8. An Integrated Process of Ionic Liquid Pretreatment and Enzymatic Hydrolysis of Lignocellulosic Biomass with Immobilised Cellulase

    Directory of Open Access Journals (Sweden)

    Mihaela Ungurean

    2014-08-01

    Full Text Available An integrated process of lignocellulosic biomass conversion was set up involving pretreatment by an ionic liquid (IL and hydrolysis of cellulose using cellulase immobilised by the sol-gel method, with recovery and reuse of both the IL and biocatalyst. As all investigated ILs, regardless of the nature of the anion and the cation, led to the loss of at least 50% of the hydrolytic activity of cellulase, the preferred solution involved reprecipitation of cellulose and lignin after the pretreatment, instead of performing the enzymatic hydrolysis in the same reaction system. The cellulose recovered after pretreatment with 1-ethyl-3-methylimidazolium acetate ([Emim][Ac] and dimethylsulfoxide (DMSO (1:1 ratio, v/v was hydrolysed with almost double yield after 8 h of reaction time with the immobilised cellulase, compared to the reference microcrystalline cellulose. The dissolution capacity of the pretreatment mixture was maintained at satisfactory level during five reuse cycles. The immobilised cellulase was recycled in nine reaction cycles, preserving about 30% of the initial activity.

  9. Multi-scale processes of beech wood disintegration and pretreatment with 1-ethyl-3-methylimidazolium acetate/water mixtures.

    Science.gov (United States)

    Viell, Jörn; Inouye, Hideyo; Szekely, Noemi K; Frielinghaus, Henrich; Marks, Caroline; Wang, Yumei; Anders, Nico; Spiess, Antje C; Makowski, Lee

    2016-01-01

    The valorization of biomass for chemicals and fuels requires efficient pretreatment. One effective strategy involves the pretreatment with ionic liquids which enables enzymatic saccharification of wood within a few hours under mild conditions. This pretreatment strategy is, however, limited by water and the ionic liquids are rather expensive. The scarce understanding of the involved effects, however, challenges the design of alternative pretreatment concepts. This work investigates the multi length-scale effects of pretreatment of wood in 1-ethyl-3-methylimidazolium acetate (EMIMAc) in mixtures with water using spectroscopy, X-ray and neutron scattering. The structure of beech wood is disintegrated in EMIMAc/water mixtures with a water content up to 8.6 wt%. Above 10.7 wt%, the pretreated wood is not disintegrated, but still much better digested enzymatically compared to native wood. In both regimes, component analysis of the solid after pretreatment shows an extraction of few percent of lignin and hemicellulose. In concentrated EMIMAc, xylan is extracted more efficiently and lignin is defunctionalized. Corresponding to the disintegration at macroscopic scale, SANS and XRD show isotropy and a loss of crystallinity in the pretreated wood, but without distinct reflections of type II cellulose. Hence, the microfibril assembly is decrystallized into rather amorphous cellulose within the cell wall. The molecular and structural changes elucidate the processes of wood pretreatment in EMIMAc/water mixtures. In the aqueous regime with >10.7 wt% water in EMIMAc, xyloglucan and lignin moieties are extracted, which leads to coalescence of fibrillary cellulose structures. Dilute EMIMAc/water mixtures thus resemble established aqueous pretreatment concepts. In concentrated EMIMAc, the swelling due to decrystallinization of cellulose, dissolution of cross-linking xylan, and defunctionalization of lignin releases the mechanical stress to result in macroscopic disintegration of

  10. Optimization of Pre-Treatment Process Parameters to Generate Biodiesel from Microalga

    Directory of Open Access Journals (Sweden)

    Chukwuma Onumaegbu

    2018-03-01

    Full Text Available Cell disruption is an integral part of microalga production process, which improves the release of intracellular products that are essential for biofuel production. In this work, pre-treatment parameters that will enhance the efficiency of lipid production using high-pressure homogenizer on microalgae biomass will be investigated. The high-pressure homogenizer that is considered is a GYB40-10S/GY60-6S; with a pre-treatment pressure of 1000 psi, 2000 psi, and 3000 psi, the number of passes; 1, 2, and 3, a reaction time of 3, 3.5, and 4 h. Pressure and cavitation increase the efficiency of the pre-treatment process of the homogenizer. In addition, homogenization shear force and pressure are the basic significant factors that enhance the efficiency of microalgae cell rupture. Also, the use of modelling to simulate pre-treatment processes (Response Surface Methodology (RSM, Box-Behnken Designs (BBD, and design of experiment (DOE for process optimization will be adopted in this study. The results clearly demonstrate that high-pressure homogenization pre-treatment can effectively disrupt microalga cell walls to enhance lipid recovery efficiency, with a relatively short extraction time, both that are essential for maintaining a good quality of lipids for biofuel production. A maximum of 18% lipid yields were obtained after 3 h of HPH pre-treatment at 3000 psi.

  11. Effect of pretreatments and processing conditions on anti-nutritional factors in climbing bean flours

    Directory of Open Access Journals (Sweden)

    Emmanuel Mugabo

    2017-04-01

    Full Text Available It is difficult for many Rwandans to utilize climbing bean seeds (Phaseolus vulgaris. L mainly because of longer cooking time (2 hours and the high consumption of basic fuel. Climbing beans also contain anti-nutritional factors such tannins, phytates, trypsin inhibitors and phytohemagglutinins that limit nutrient absorption. One way to solve this problem is to utilize the flour of climbing beans made from different treatments and processing methods. In this study, climbing beans were pre-treated by soaking them in water for 24 hours, soaking in 2% sodium bicarbonate solution and steam blanching for 10 minutes. After that, pre-treated climbing beans were processed into flours by processing methods such as roasting, cooking and germination where anti-nutritional factors were reduced. The pretreatments did not significantly (p>0.05 affect phytates in climbing bean flours but processing conditions significantly (p<0.05 reduced it. Pretreatments and processing conditions significantly (p<0.05 reduced tannin content. The pretreatments followed by different processing conditions significantly (p<0.05 decreased trypsin inhibitors content. The great significant decrease in phytohemagglutinins content was observed in pretreatment followed by different processing methods. All pretreatments and processing conditions effectively decreased anti-nutritional factors at low level. However, pretreatments or untreated followed by germination and roasting were found to be the most and the least effective respectively.  Making flour from germinated climbing bean seeds is a good option for sustainable food processing as it reduces anti-nutritional factors. It is an inexpensive method in terms of time, energy and fuel for Rwandan households, restaurants and industries where climbing bean seeds are integral part of daily meal.

  12. Process and technoeconomic analysis of leading pretreatment technologies for lignocellulosic ethanol production using switchgrass.

    Science.gov (United States)

    Tao, Ling; Aden, Andy; Elander, Richard T; Pallapolu, Venkata Ramesh; Lee, Y Y; Garlock, Rebecca J; Balan, Venkatesh; Dale, Bruce E; Kim, Youngmi; Mosier, Nathan S; Ladisch, Michael R; Falls, Matthew; Holtzapple, Mark T; Sierra, Rocio; Shi, Jian; Ebrik, Mirvat A; Redmond, Tim; Yang, Bin; Wyman, Charles E; Hames, Bonnie; Thomas, Steve; Warner, Ryan E

    2011-12-01

    Six biomass pretreatment processes to convert switchgrass to fermentable sugars and ultimately to cellulosic ethanol are compared on a consistent basis in this technoeconomic analysis. The six pretreatment processes are ammonia fiber expansion (AFEX), dilute acid (DA), lime, liquid hot water (LHW), soaking in aqueous ammonia (SAA), and sulfur dioxide-impregnated steam explosion (SO(2)). Each pretreatment process is modeled in the framework of an existing biochemical design model so that systematic variations of process-related changes are consistently captured. The pretreatment area process design and simulation are based on the research data generated within the Biomass Refining Consortium for Applied Fundamentals and Innovation (CAFI) 3 project. Overall ethanol production, total capital investment, and minimum ethanol selling price (MESP) are reported along with selected sensitivity analysis. The results show limited differentiation between the projected economic performances of the pretreatment options, except for processes that exhibit significantly lower monomer sugar and resulting ethanol yields. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Energy efficacy used to score organic refuse pretreatment processes for hydrogen anaerobic production.

    Science.gov (United States)

    Ruggeri, Bernardo; Luongo Malave, Andrea C; Bernardi, Milena; Fino, Debora

    2013-11-01

    The production of hydrogen through Anaerobic Digestion (AD) has been investigated to verify the efficacy of several pretreatment processes. Three types of waste with different carbon structures have been tested to obtain an extensive representation of the behavior of the materials present in Organic Waste (OW). The following types of waste were selected: Sweet Product Residue (SPR), i.e., confectionary residue removed from the market after the expiration date, Organic Waste Market (OWM) refuse from a local fruit and vegetable market, and Coffee Seed Skin (CSS) waste from a coffee production plant. Several pretreatment processes have been applied, including physical, chemical, thermal, and ultrasonic processes and a combination of these processes. Two methods have been used for the SPR to remove the packaging, manual (SPR) and mechanical (SPRex). A pilot plant that is able to extrude the refuse to 200atm was utilized. Two parameters have been used to score the different pretreatment processes: efficiency (ξ), which takes into account the amount of energy produced in the form of hydrogen compared with the available energy embedded in the refuse, and efficacy (η), which compares the efficiency obtained using the pretreated refuse with that obtained using the untreated refuse. The best result obtained for the SPR was the basic pretreatment, with η=6.4, whereas the thermal basic pretreatment gave the highest value, η=17.0 for SPRex. The best result for the OWM was obtained through a combination of basic/thermal pretreatments with η=9.9; lastly, the CSS residue with ultrasonic pretreatment produced the highest quantity of hydrogen, η=5.2. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Review of pretreatment processes for lignocellulosic ethanol production, and development of an innovative method

    International Nuclear Information System (INIS)

    Chiaramonti, David; Prussi, Matteo; Ferrero, Simone; Oriani, Luis; Ottonello, Piero; Torre, Paolo; Cherchi, Francesco

    2012-01-01

    Biomass pretreatment aims at separating and providing easier access to the main biomass components (cellulose, hemicellulose and lignin), eventually removing lignin, preserving the hemicellulose, reducing the cellulose crystallinity and increasing the porosity of the material. Pretreatment is an essential step towards the development and industrialization of efficient 2nd generation lignocellulosic ethanol processes. The present work reviewed the main options available in pretreatment. Autohydrolysis and steam explosion were then selected for further investigation. Experimental work was carried out on batch scale reactors, using Miscanthus as biomass feedstock: the effects on sugar solubilization and degradation products generation have been examined for each of these two pretreatment systems. A new process using only water and steam as reacting media was then developed, experimentally tested, and results compared to those achieved by the autohydrolysis and steam explosion processes. Products obtained with the new pretreatment contained a lower amount of usual fermentation inhibitor compounds compared to that typically obtained in steam explosion. This result was achieved under operating conditions that at the same time allowed a good xylan yield, preventing degradation of hemicelluloses. The new pretreatment process was also able to act as an equalization step, as the solid material from the pretreatment phase had a similar composition even under different operating conditions. As regards the effect of pretreatment on enzymatic hydrolysis, the new process achieved yields similar to steam explosion on glucans: however, this was obtained reducing the formation of degradation products from sugars, mainly from C5 sugars. These results made the proposed pretreatment system suitable for further development and industrialization on pilot and industrial scale.

  15. Combination of alkaline and microwave pretreatment for disintegration of meat processing wastewater sludge.

    Science.gov (United States)

    Erden, G

    2013-01-01

    Meat processing wastewater sludge has high organic content but it is very slow to degrade in biological processes. Anaerobic digestion may be a good alternative for this type of sludge when the hydrolysis, known to be the rate-limiting step of biological sludge anaerobic degradation, could be eliminated by disintegration. This investigation deals with disintegration of meat processing wastewater sludge. Microwave (MW) irradiation and combined alkaline pretreatment and MW irradiation were applied to sludge for disintegration purposes. Disintegration performance of the methods was evaluated with disintegration degree based on total and dissolved organic carbon calculations (DD(TOC)), and the solubilization of volatile solids (S(VS)) in the pretreated sludge. Optimum conditions were found to be 140 degrees C and 30 min for MW irradiation using response surface methodology (RSM) and pH = 13 for combined pretreatment. While DD(TOC) was observed as 24.6% and 54.9, S(VS) was determined as 8.54% and 42.5% for MW pretreated and combined pretreated sludge, respectively. The results clearly show that pre-conditioning of sludge with alkaline pretreatment played an important role in enhancing the disintegration efficiency of subsequent MW irradiation. Disintegration methods also affected the anaerobic biodegradability and dewaterability of sludge. An increase of 23.6% in biogas production in MW irradiated sludge was obtained, comparing to the raw sludge at the end of the 35 days of incubation. This increase was observed as 44.5% combined pretreatment application. While MW pretreatment led to a little improvement of the dewatering performance of sludge, in combined pretreatment NaOH deteriorates the sludge dewaterability.

  16. Effects of pretreatment processes on improving the formation of ultrananocrystalline diamond

    International Nuclear Information System (INIS)

    Chen, Li-Ju; Tai, Nyan-Hwa; Lee, Chi-Young; Lin, I-Nan.

    2007-01-01

    Effects of pretreatment on the nuclei formation of ultrananocrystalline diamond (UNCD) on Si substrates were studied. Either precoating a thin layer of titanium (∼400 nm) or ultrasonication pretreatment using diamond and titanium mixed powder (D and T process) enhances the nucleation process on Si substrates markedly, and the UNCD nuclei formed and fully covered the Si substrate, when deposition was processed using the microwave-plasma-enhanced chemical-vapor deposition process for 10 min. In contrast, during the same period, ultrasonication pretreatment using diamond powders (D process) can only form large UNCD clusters, which were scarcely distributed on Si substrates. The analyses using x-ray diffractometer, secondary ion mass spectroscopy, and electron spectroscopy for chemical analysis reveal that the titanium layer reacted with carbon species in the plasma, forming crystalline TiC phase, which facilitates the subsequent formation of UNCD nuclei. The beneficial effect of Ti layer on enhancing the nucleation of UNCD is presumably owing to high solubility and high diffusivity of carbon species in Ti materials, as compared with those of Si materials

  17. Pretreatment of Cellulose By Electron Beam Irradiation Method

    Science.gov (United States)

    Jusri, N. A. A.; Azizan, A.; Ibrahim, N.; Salleh, R. Mohd; Rahman, M. F. Abd

    2018-05-01

    Pretreatment process of lignocellulosic biomass (LCB) to produce biofuel has been conducted by using various methods including physical, chemical, physicochemical as well as biological. The conversion of bioethanol process typically involves several steps which consist of pretreatment, hydrolysis, fermentation and separation. In this project, microcrystalline cellulose (MCC) was used in replacement of LCB since cellulose has the highest content of LCB for the purpose of investigating the effectiveness of new pretreatment method using radiation technology. Irradiation with different doses (100 kGy to 1000 kGy) was conducted by using electron beam accelerator equipment at Agensi Nuklear Malaysia. Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD) analyses were studied to further understand the effect of the suggested pretreatment step to the content of MCC. Through this method namely IRR-LCB, an ideal and optimal condition for pretreatment prior to the production of biofuel by using LCB may be introduced.

  18. Mild-temperature dilute acid pretreatment for integration of first and second generation ethanol processes.

    Science.gov (United States)

    Nair, Ramkumar B; Kalif, Mahdi; Ferreira, Jorge A; Taherzadeh, Mohammad J; Lennartsson, Patrik R

    2017-12-01

    The use of hot-water (100°C) from the 1st generation ethanol plants for mild-temperature lignocellulose pretreatment can possibly cut down the operational (energy) cost of 2nd generation ethanol process, in an integrated model. Dilute-sulfuric and -phosphoric acid pretreatment at 100°C was carried out for wheat bran and whole-stillage fibers. Pretreatment time and acid type influenced the release of sugars from wheat bran, while acid-concentration was found significant for whole-stillage fibers. Pretreatment led up-to 300% improvement in the glucose yield compared to only-enzymatically treated substrates. The pretreated substrates were 191-344% and 115-300% richer in lignin and glucan, respectively. Fermentation using Neurospora intermedia, showed 81% and 91% ethanol yields from wheat bran and stillage-fibers, respectively. Sawdust proved to be a highly recalcitrant substrate for mild-temperature pretreatment with only 22% glucose yield. Both wheat bran and whole-stillage are potential substrates for pretreatment using waste heat from the 1st generation process for 2nd generation ethanol. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. RT-CaCCO process: an improved CaCCO process for rice straw by its incorporation with a step of lime pretreatment at room temperature.

    Science.gov (United States)

    Shiroma, Riki; Park, Jeung-yil; Al-Haq, Muhammad Imran; Arakane, Mitsuhiro; Ike, Masakazu; Tokuyasu, Ken

    2011-02-01

    We improved the CaCCO process for rice straw by its incorporation with a step of lime pretreatment at room temperature (RT). We firstly optimized the RT-lime pretreatment for the lignocellulosic part. When the ratio of lime/dry-biomass was 0.2 (w/w), the RT lime-pretreatment for 7-d resulted in an effect on the enzymatic saccharification of cellulose and xylan equivalent to that of the pretreatment at 120°C for 1h. Sucrose, starch and β-1,3-1,4-glucan, which could be often detected in rice straw, were mostly stable under the RT-lime pretreatment condition. Then, the pretreatment condition in the conventional CaCCO process was modified by the adaptation of the optimized RT lime-pretreatment, resulting in significantly better carbohydrate recoveries via enzymatic saccharification than those of the CaCCO process (120°C for 1 h). Thus, the improved CaCCO process (the RT-CaCCO process) could preserve/pretreat the feedstock at RT in a wet form with minimum loss of carbohydrates. Copyright © 2010 Elsevier Ltd. All rights reserved.

  20. Microwave heating processing as alternative of pretreatment in second-generation biorefinery: An overview

    International Nuclear Information System (INIS)

    Aguilar-Reynosa, Alejandra; Romaní, Aloia; Rodríguez-Jasso, Rosa Ma.; Aguilar, Cristóbal N.; Garrote, Gil; Ruiz, Héctor A.

    2017-01-01

    Highlights: • Microwave heating pretreatment for lignocellulosic material. • Fundament of lignocellulosic material fractionation using microwave irradiation. • Energy consumption in microwave pretreatments and microwave reactors description. • Microwave heating as pretreatment in a biorefinery concept. - Abstract: The development of a feasible biorefinery is in need of alternative technologies to improve lignocellulosic biomass conversion by the suitable use of energy. Microwave heating processing (MHP) is emerging as promising unconventional pretreatment of lignocellulosic materials (LCMs). MHP applied as pretreatment induces LCMs breakdown through the molecular collision caused by the dielectric polarization. Polar particles movement generates a quick heating consequently the temperatures and times of process are lower. In this way, MHP has positioned as green technology in comparison with other types of heating. Microwave technology represents an excellent option to obtain susceptible substrates to enzymatic saccharification and subsequently in the production of bioethanol and high-added compounds. However, it is still necessary to study the dielectric properties of materials, and conduct economic studies to achieve development in pilot and industrial scale. This work aims to provide an overview of recent progress and alternative configurations for combining the application of microwave technology on the pretreatment of LCMs in terms of biorefinery.

  1. Impact of pretreatment and downstream processing technologies on economics and energy in cellulosic ethanol production

    Directory of Open Access Journals (Sweden)

    Murthy Ganti S

    2011-09-01

    Full Text Available Abstract Background While advantages of biofuel have been widely reported, studies also highlight the challenges in large scale production of biofuel. Cost of ethanol and process energy use in cellulosic ethanol plants are dependent on technologies used for conversion of feedstock. Process modeling can aid in identifying techno-economic bottlenecks in a production process. A comprehensive techno-economic analysis was performed for conversion of cellulosic feedstock to ethanol using some of the common pretreatment technologies: dilute acid, dilute alkali, hot water and steam explosion. Detailed process models incorporating feedstock handling, pretreatment, simultaneous saccharification and co-fermentation, ethanol recovery and downstream processing were developed using SuperPro Designer. Tall Fescue (Festuca arundinacea Schreb was used as a model feedstock. Results Projected ethanol yields were 252.62, 255.80, 255.27 and 230.23 L/dry metric ton biomass for conversion process using dilute acid, dilute alkali, hot water and steam explosion pretreatment technologies respectively. Price of feedstock and cellulose enzymes were assumed as $50/metric ton and 0.517/kg broth (10% protein in broth, 600 FPU/g protein respectively. Capital cost of ethanol plants processing 250,000 metric tons of feedstock/year was $1.92, $1.73, $1.72 and $1.70/L ethanol for process using dilute acid, dilute alkali, hot water and steam explosion pretreatment respectively. Ethanol production cost of $0.83, $0.88, $0.81 and $0.85/L ethanol was estimated for production process using dilute acid, dilute alkali, hot water and steam explosion pretreatment respectively. Water use in the production process using dilute acid, dilute alkali, hot water and steam explosion pretreatment was estimated 5.96, 6.07, 5.84 and 4.36 kg/L ethanol respectively. Conclusions Ethanol price and energy use were highly dependent on process conditions used in the ethanol production plant. Potential for

  2. Application of Alkaline Ionic Liquids in the Pretreatment Process of Eucalyptus Kraft Pulping

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    Yi Hou

    2016-09-01

    Full Text Available In order to explore the potential application of green solvent ionic liquids (ILs in the kraft pulping process, eucalyptus wood was pretreated by [Mmim]DMP before normal pulping. The results showed that materials pretreated shortly by the ionic liquid had a higher yield and viscosity coupled with a lower potassium permanganate value and residual lignin content in the pulp, as a result of the cooking process. It was also inferred that alkaline [Mmim]DMP pretreatment could dissolve lignin effectively from fiber to result in a stronger binding force and more entangled properties. Paper tensile and burst strength were improved by about 40% and 60%, respectively. These results provide a new way for eucalyptus to be utilized in the kraft pulping process.

  3. The effect of dilute acid pre-treatment process in bioethanol production from durian (Durio zibethinus) seeds waste

    Science.gov (United States)

    Ghazali, K. A.; Salleh, S. F.; Riayatsyah, T. M. I.; Aditiya, H. B.; Mahlia, T. M. I.

    2016-03-01

    Lignocellulosic biomass is one of the promising feedstocks for bioethanol production. The process starts from pre-treatment, hydrolysis, fermentation, distillation and finally obtaining the final product, ethanol. The efficiency of enzymatic hydrolysis of cellulosic biomass depends heavily on the effectiveness of the pre-treatment step which main function is to break the lignin structure of the biomass. This work aims to investigate the effects of dilute acid pre-treatment on the enzymatic hydrolysis of durian seeds waste to glucose and the subsequent bioethanol fermentation process. The yield of glucose from dilute acid pre-treated sample using 0.6% H2SO4 and 5% substrate concentration shows significant value of 23.4951 g/L. Combination of dilute acid pre-treatment and enzymatic hydrolysis using 150U of enzyme able to yield 50.0944 g/L of glucose content higher compared to normal pre-treated sample of 8.1093 g/L. Dilute acid pre-treatment sample also shows stable and efficient yeast activity during fermentation process with lowest glucose content at 2.9636 g/L compared to 14.7583g/L for normal pre-treated sample. Based on the result, it can be concluded that dilute acid pre-treatment increase the yield of ethanol from bioethanol production process.

  4. Ethanol from softwood. Process development based on steam pretreatment and SSF

    Energy Technology Data Exchange (ETDEWEB)

    Stenberg, Kerstin

    1999-05-01

    Fuel ethanol can be produced from lignocellulosics by the enzymatic hydrolysis process, which consists of a pretreatment step prior to hydrolysis, followed by fermentation and finally refining. This thesis deals with the development of the enzymatic process using softwood as raw material. The focus has not only been on how to obtain high yields, but also on how to solve problems, which can arise in an industrial process, such as inhibition and contamination. The pretreatment step was evaluated using steam-pretreatment and impregnation with an acid catalyst, either SO{sub 2} or H{sub 2}SO{sub 4}. Both impregnation methods resulted in approximately the same yield, 65% of the theoretical of fermentable sugars, i.e. glucose and mannose, after enzymatic hydrolysis. However, impregnation with SO{sub 2}, resulted in higher ethanol productivity and yield in the fermentation. Simultaneous saccharification and fermentation (SSF) was investigated using various substrate and cellulase concentrations. An overall ethanol yield of 70% of the theoretical was obtained using the whole slurry from the pretreatment step at an insoluble dry weight content of 5%, which was shown to be optimal. SSF resulted in both higher productivity and higher ethanol yield than in separate hydrolysis and fermentation, but proved to be more sensitive to infection by lactic aid bacteria. More complex process integration, in the form of recirculation of process streams, which is desirable in an industrial process, was investigated using bench-scale equipment. A reduction in the fresh-water demand of 50%, from 3 kg/kg dry raw material to 1.5 kg/kg dry raw material, was found to be possible without any negative effects on either hydrolysis or fermentation. A techno-economic evaluation of different process configurations in a process applying SSF was also performed. It was found that the ethanol production cost could be reduced by 20% by internal energy integration and by another 15% by recirculation to the

  5. Anaerobic digestion of organic by-products from meat-processing industry. The effect of pre-treatments and co-digestion

    Energy Technology Data Exchange (ETDEWEB)

    Luste, S.

    2011-07-01

    suitable for anaerobic co-digestion. The co-digestion of the ABPs with sewage sludge and cattle slurry resulted improved methane production and reusability of the digestate. These enhancements were further improved by the pre-treatments studied. The most suitable (ultrasound and bacterial product addition) and synergistically beneficial (pre-hygienisation) pretreatments were found to enhance the complex degradation of materials. Pre-treatments effects on the whole process and on the end-products were depended on the hydrolysis values, but especially on the content of the materials and qualities of the solubilised compounds. Economical feasibility of ultrasound and hygienisation pre-treatments is attainable. Materials and process methods studied in this thesis offer required new information and aspects about the case- and material-specific factors of process requirements, process optimisation according to the requirements in practice, degradability of the ABP materials, hygienic matters and mechanisms involved in pre-treatments and co-digestion of ABPs. The information produced could be directly utilised in the practical implementations of the anaerobic digestion of studied or corresponding materials and feed mixtures. (orig.)

  6. Design Criteria for Process Wastewater Pretreatment Facilities

    Science.gov (United States)

    1988-05-01

    Stripping Column H13 ’Re Purpose: The purpose of this report, is to provide design criteria for pretreatment needs for ’ I. INTRODUCTION ’". discharge of...which a portion of the vessel is filled with packing. Packing materials vary from corrugated steel to bundles of fibers (Langdon et al., 1972) to beds...concentration(s) using Table 20. Wastewater treatability studies should be considered as a process-screening tool for all wastewater streams for

  7. Impacts of operating parameters on oxidation-reduction potential and pretreatment efficacy in the pretreatment of printing and dyeing wastewater by Fenton process

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Huifang, E-mail: whfkhl@sina.com [College of Environment, Jiangsu Key Laboratory of Industrial Water-Conservation and Emission Reduction, Nanjing University of Technology, Nanjing 210009 (China); Wang, Shihe [Department of Municipal Engineering, Southeast University, Nanjing 210096 (China)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer A real printing and dyeing wastewater was pretreated by Fenton process. Black-Right-Pointing-Pointer We investigated impacts of operating parameters on ORP and pretreatment efficacy. Black-Right-Pointing-Pointer Relationship among ORP, operating parameters and treatment efficacy was established. Black-Right-Pointing-Pointer Pretreatment efficacy was in proportion to the exponent of temperature reciprocal. Black-Right-Pointing-Pointer We investigated kinetics of color and COD removal and BOD{sub 5}/COD ratio in solution. - Abstract: An experiment was conducted in a batch reactor for a real printing and dyeing wastewater pretreatment using Fenton process in this study. The results showed that original pH, hydrogen peroxide concentration and ferrous sulfate concentration affected ORP value and pretreatment efficacy greatly. Under experimental conditions, the optimal original pH was 6.61, and the optimal hydrogen peroxide and ferrous sulfate concentrations were 1.50 and 0.75 g L{sup -1}, respectively. The relationship among ORP, original pH, hydrogen peroxide concentration, ferrous sulfate concentration, and color (COD or BOD{sub 5}/COD) was established, which would be instructive in on-line monitoring and control of Fenton process using ORP. In addition, the effects of wastewater temperature and oxidation time on pretreatment efficacy were also investigated. With an increase of temperature, color and COD removal efficiencies and BOD{sub 5}/COD ratio increased, and they were in proportion to the exponent of temperature reciprocal. Similarly, color and COD removal efficiencies increased with increasing oxidation time, and both color and COD removal obeyed the first-order kinetics. The BOD{sub 5}/COD ratio could be expressed by a second-degree polynomial with respect to oxidation time, and the best biodegradability of wastewater was present at the oxidation time of 6.10 h.

  8. Impacts of operating parameters on oxidation–reduction potential and pretreatment efficacy in the pretreatment of printing and dyeing wastewater by Fenton process

    International Nuclear Information System (INIS)

    Wu, Huifang; Wang, Shihe

    2012-01-01

    Highlights: ► A real printing and dyeing wastewater was pretreated by Fenton process. ► We investigated impacts of operating parameters on ORP and pretreatment efficacy. ► Relationship among ORP, operating parameters and treatment efficacy was established. ► Pretreatment efficacy was in proportion to the exponent of temperature reciprocal. ► We investigated kinetics of color and COD removal and BOD 5 /COD ratio in solution. - Abstract: An experiment was conducted in a batch reactor for a real printing and dyeing wastewater pretreatment using Fenton process in this study. The results showed that original pH, hydrogen peroxide concentration and ferrous sulfate concentration affected ORP value and pretreatment efficacy greatly. Under experimental conditions, the optimal original pH was 6.61, and the optimal hydrogen peroxide and ferrous sulfate concentrations were 1.50 and 0.75 g L −1 , respectively. The relationship among ORP, original pH, hydrogen peroxide concentration, ferrous sulfate concentration, and color (COD or BOD 5 /COD) was established, which would be instructive in on-line monitoring and control of Fenton process using ORP. In addition, the effects of wastewater temperature and oxidation time on pretreatment efficacy were also investigated. With an increase of temperature, color and COD removal efficiencies and BOD 5 /COD ratio increased, and they were in proportion to the exponent of temperature reciprocal. Similarly, color and COD removal efficiencies increased with increasing oxidation time, and both color and COD removal obeyed the first-order kinetics. The BOD 5 /COD ratio could be expressed by a second-degree polynomial with respect to oxidation time, and the best biodegradability of wastewater was present at the oxidation time of 6.10 h.

  9. Expression of three sHSP genes involved in heat pretreatment-induced chilling tolerance in banana fruit.

    Science.gov (United States)

    He, Li-hong; Chen, Jian-ye; Kuang, Jian-fei; Lu, Wang-jin

    2012-07-01

    Banana fruit is highly susceptible to chilling injury. In previous research it was shown that heat pretreatment of banana fruit at 38 °C for 3 days before storage at a chilling temperature of 8 °C for 12 days prevented increases in visible chilling injury index, electrolyte leakage and malondialdehyde content and also decreases in lightness and chroma, indicating that heat pretreatment could effectively alleviate chilling injury of banana fruit. However, little is known about the role of small heat shock proteins (sHSPs) in postharvest chilling tolerance of banana fruit. In the present study, three cytosolic sHSP expression profiles in peel and pulp tissues of banana fruit during heat pretreatment and subsequent chilled storage (8 °C) were investigated in relation to heat pretreatment-induced chilling tolerance. Three full-length cDNAs of cytosolic sHSP genes, including two class I sHSP (CI sHSP) and one class II sHSP (CII sHSP) cDNAs, named Ma-CI sHSP1, Ma-CI sHSP2 and Ma-CII sHSP3 respectively, were isolated and characterised from harvested banana fruit. Accumulation of Ma-CI sHSP1 mRNA transcripts in peel and pulp tissues and Ma-CII sHSP3 mRNA transcripts in peel tissue increased during heat pretreatment. Expression of all three Ma-sHSP genes in peel and pulp tissues was induced during subsequent chilled storage. Furthermore, Ma-CI sHSP1 and Ma-CII sHSP3 mRNA transcripts in pulp tissue and Ma-CI sHSP2 mRNA transcripts in peel and pulp tissues were obviously enhanced by heat pretreatment at days 6 and 9 of subsequent chilled storage. These results suggested that heat pretreatment enhanced the expression of Ma-sHSPs, which might be involved in heat pretreatment-induced chilling tolerance of banana fruit. Copyright © 2012 Society of Chemical Industry.

  10. Am/Cm Vitrification Process: Pretreatment Material Balance Calculations

    International Nuclear Information System (INIS)

    Smith, F.G.

    2001-01-01

    This report documents material balance calculations for the pretreatment steps required to prepare the Americium/Curium solution currently stored in Tank 17.1 in the F-Canyon for vitrification. The material balance uses the latest analysis of the tank contents to provide a best estimate calculation of the expected plant operations during the pretreatment process. The material balance calculations primarily follow the material that directly leads to melter feed. Except for vapor products of the denitration reactions and treatment of supernate from precipitation and precipitate washing, the flowsheet does not include side streams such as acid washes of the empty tanks that would go directly to waste. The calculation also neglects tank heels. This report consolidates previously reported results, corrects some errors found in the spreadsheet and provides a more detailed discussion of the calculation basis

  11. Development of an integrated pretreatment fractionation process for fermentable sugars and lignin: Application to almond (Prunus dulcis) shell

    International Nuclear Information System (INIS)

    Gong, Dachun; Holtman, Kevin M.; Franqui-Espiet, Diana; Orts, William J.; Zhao, Ruming

    2011-01-01

    An environmentally friendly pretreatment process was developed to fractionate cellulose, hemicellulose and lignin from almond (Prunus dulcis) shells, consisting of hot water pretreatment (HWP) coupled with organic solvent (organosolv) pretreatment of water/ethanol (OWEP). This integrated pretreatment process proved more effective on the basis of yield of fermentable sugar and lignin separation compared with HWP alone, dilute acid pretreatment (DAP), ammonia pretreatment (AP), lime pretreatment LP, organosolv water/ethanol pretreatment (OWEP), and organosolv water/acetone pretreatment (OWAP). In the coupled hot water-organosolv process, hemicellulose sugars were recovered in the first residual liquid while varying amounts of cellulose was retained in the residual solid. The lignin fraction was obtained by simply adjusting the pH from the second liquid. The optimal two-stage process consisted of first HWP stage at 195 o C for 30 min, resulting in w glucose = 95.4% glucose recovery yield and w xylose = 92.2% xylose removal. The second organosolv OWEP stage was operated at 195 o C for 20 min, in ethanol in water mixtures of ethanol = 50% and resulted in nearly w glucose = 100% glucose recovery yield, w xylose = 90% xylose and w lignin = 61% lignin removal. After enzymatic hydrolysis, glucose yield was up to w glucose = 95%, compared to 61% yield from untreated almond. Images obtained via scanning electron microscopy (SEM) highlighted the differences in almond structure from the varying pretreatment methods during biomass fractionation. -- Highlights: → Almond shells are an under-utilized agriculture byproduct available in the world. → Almond shells are particularly attractive as bioenergy feedstock. → We have developed a new fractionation process for the almond shell. → The new process combined the HWP with OWEP. → The fractionation process has potential in the utilization of almond shell.

  12. Laboratory Tests on Post-Filtration Precipitation in the WTP Pretreatment Process

    International Nuclear Information System (INIS)

    Russell, Renee L.; Peterson, Reid A.; Rinehart, Donald E.; Crum, Jarrod V.

    2009-01-01

    Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed, and operated as part of a plan to respond to issue M12, 'Undemonstrated Leaching Processes,' of the External Flowsheet Review Team (EFRT) issue response plan (Barnes et al. 2006). The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. A simplified flow diagram of the PEP system is shown in Figure 1.1. Two operating scenarios are currently being evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario has caustic leaching performed in the UFP-2 ultrafiltration feed vessels (i.e., vessel UFP-VSL-T02A in the PEP; and vessels UFP-VSL-00002A and B in the WTP PTF). The second scenario has caustic leaching conducted in the UFP-1 ultrafiltration feed preparation vessels (i.e., vessels UFP-VSL-T01A and B in the PEP; vessels UFP-VSL-00001A and B in the WTP PTF).

  13. Process intensification effect of ball milling on the hydrothermal pretreatment for corn straw enzymolysis

    International Nuclear Information System (INIS)

    Yuan, Zhengqiu; Long, Jinxing; Wang, Tiejun; Shu, Riyang; Zhang, Qi; Ma, Longlong

    2015-01-01

    Highlights: • Novel pretreatment of ball milling combined with hydrothermal method was presented. • Intensification effect of ball milling was significant for corn straw enzymolysis. • Ball milling destroyed the physical structure of corn straw. • Chemical (liquid mixture) method removed lignin and hemicellulose. • Glucose yield increased from 0.41 to 13.86 mg mL −1 under the optimized condition. - Abstract: Enhancement of the cellulose accessibility is significant for biomass enzymatic hydrolysis. Here, we reported an efficient combined pretreatment for corn straw enzymolysis using ball milling and dilute acid hydrothermal method (a mixture solvent of H 2 O/ethanol/sulfuric acid/hydrogen peroxide liquid). The process intensification effect of ball milling on the pretreatment of the corn straw was studied through the comparative characterization of the physical–chemical properties of the raw and pretreated corn straw using FT-IR, BET, XRD, SEM, and HPLC analysis. The effect of the pretreatment temperature was also investigated. Furthermore, various pretreatment methods were compared as well. Moreover, the pretreatment performance was measured by enzymolysis. The results showed that ball milling had a significant process intensification effect on the corn straw enzymolysis. The glucose concentration was dramatically increased from 0.41 to 13.86 mg mL −1 after the combined treatment of ball milling and hydrothermal. The efficient removal of lignin and hemicellulose and the enlargement of the surface area were considered to be responsible for this significant increase based on the intensive analysis on the main components and the physical–chemical properties of the raw and pretreated corn straw

  14. Improvement of Haramay Fiber by Pre-treatment of Retting Process withPhosphoric Acid

    International Nuclear Information System (INIS)

    Kuntari-Sasas; Neni-Rustini Eriawati

    2000-01-01

    Haramay as bast fiber contains of cellulose fiber as the main part, mixedwith hemi cellulose, pectin, and lignin as binding material for cellulosefiber to keep it together in the bundle form. For textile material, this bastfiber has to be freed from its binding material, called as retting process,before subjecting to scouring, dyeing and finishing process in textileindustry. In the retting process the dissolve of binding material can be doneeither by using enzyme in bio technology or extraction with strong alkalinecondition in common technology. Using sodium hydroxide for dissolving thebinding material can be carried out easily with good dissolving ability, butcan render the strength retention of the cellulose fiber. Pre-treatment ofthe bast fiber with phosphoric acid (H 3 PO 4 ), is expected to hydrolyze someof the binding materials that can not be dissolved in alkaline condition,including natural pigment that colored the fiber with creamy white. In thisstudy, the pre-treatment process before retting with phosphoric acid wascarried out in various condition, such as concentration of phosphoric acid (5ml/l- 25 ml/l), time and temperature of pre-treatment (1-3 hours at 50 o C or12-24 hours at room temperature), followed by neutralization in dilutealkaline. The retting process was carried out by means of scouring in variousconcentration of sodium hydroxide (NaOH 38 o Be, 10 ml/l-30 m/l), and then wascontinued with bleaching process in hydrogen peroxide solution. Aftercarrying out those experiment, the bast fiber that called haramay wassubjected to testing for weight reduction, strength retention and degree ofwhiteness. From the testing results it is concluded that pre-treatment withphosphoric acid can increase the weight reduction, strength retention ortenacity and degree of whiteness of haramay fiber compared to the oneswithout pre-treatment with phosphoric acid. The best result was obtained bypre-treatment with 5 ml/l H 3 PO 4 at 50 o C for 2 hours, continued by

  15. TWRS tank waste pretreatment process development hot test siting report

    International Nuclear Information System (INIS)

    Howden, G.F.; Banning, D.L.; Dodd, D.A.; Smith, D.A.; Stevens, P.F.; Hansen, R.I.; Reynolds, B.A.

    1995-02-01

    This report is the sixth in a series that have assessed the hot testing requirements for TWRS pretreatment process development and identified the hot testing support requirements. This report, based on the previous work, identifies specific hot test work packages, matches those packages to specific hot cell facilities, and provides recommendations of specific facilities to be employed for the pretreatment hot test work. Also identified are serious limitations in the tank waste sample retrieval and handling infrastructure. Recommendations are provided for staged development of 500 mL, 3 L, 25 L and 4000 L sample recovery systems and specific actions to provide those capabilities

  16. A NEW PROCESS DEVELOPED FOR SEPARATION OF LIGNIN FROM AMMONIUM HYDROXIDE PRETREATMENT SOLUTIONS

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, S.; Gorensek, M.; Milliken, C.

    2010-12-14

    A method is described for separating lignin from liquid solutions resulting from the pretreatment of lignocellulosic materials such as switchgrass with ammonium hydroxide. The method involves a sequence of steps including acidification, evaporation, and precipitation or centrifugation that are performed under defined conditions, and results in a relatively pure, solid lignin product. The method is tested on ammonium hydroxide solutions containing lignin extracted from switchgrass. Experimental results show that the method is capable of recovering between 66-95% of dissolved lignin as a precipitated solid. Cost estimates of pilot-scale and industrial-scale expressions of the process indicate that breakeven lignin prices of $2.36/kg and $0.78/kg, respectively, may be obtainable with this recovery method.

  17. The impacts of pretreatment on the fermentability of pretreated lignocellulosic biomass: a comparative evaluation between ammonia fiber expansion and dilute acid pretreatment

    Directory of Open Access Journals (Sweden)

    Dale Bruce E

    2009-12-01

    Full Text Available Abstract Background Pretreatment chemistry is of central importance due to its impacts on cellulosic biomass processing and biofuels conversion. Ammonia fiber expansion (AFEX and dilute acid are two promising pretreatments using alkaline and acidic pH that have distinctive differences in pretreatment chemistries. Results Comparative evaluation on these two pretreatments reveal that (i AFEX-pretreated corn stover is significantly more fermentable with respect to cell growth and sugar consumption, (ii both pretreatments can achieve more than 80% of total sugar yield in the enzymatic hydrolysis of washed pretreated solids, and (iii while AFEX completely preserves plant carbohydrates, dilute acid pretreatment at 5% solids loading degrades 13% of xylose to byproducts. Conclusion The selection of pretreatment will determine the biomass-processing configuration, requirements for hydrolysate conditioning (if any and fermentation strategy. Through dilute acid pretreatment, the need for hemicellulase in biomass processing is negligible. AFEX-centered cellulosic technology can alleviate fermentation costs through reducing inoculum size and practically eliminating nutrient costs during bioconversion. However, AFEX requires supplemental xylanases as well as cellulase activity. As for long-term sustainability, AFEX has greater potential to diversify products from a cellulosic biorefinery due to lower levels of inhibitor generation and lignin loss.

  18. New pentose dimers with bicyclic moieties from pretreated biomass

    DEFF Research Database (Denmark)

    Rasmussen, H.; Sørensen, Henrik Rokkjær; Tanner, David Ackland

    2017-01-01

    In lignocellulosic biorefinery processes involving enzyme catalysed reactions it is a challenge that enzyme inhibiting compounds are generated and liberated during pretreatment of the biomass. In this study the contribution to cellulase inhibition from xylooligosaccharides and newly discovered...... oligophenolic compounds from pilot scale pretreated wheat straw was assessed at two different pretreatment severities. An increase in severity of the pretreatment led to more oligophenol compounds and in turn the total overall cellulase inhibition increased. When the xylooligosaccharides were enzymatically...... degraded prior to cellulose hydrolysis, a relief in cellulase inhibition was observed, but some inhibition remained, suggesting that other components also played a role in inhibition. We propose that these components include dipentoses with bicyclic moieties and feruloylated tripentoses, because LC...

  19. Electrochemical pretreatment of waste activated sludge: effect of process conditions on sludge disintegration degree and methane production.

    Science.gov (United States)

    Ye, Caihong; Yuan, Haiping; Dai, Xiaohu; Lou, Ziyang; Zhu, Nanwen

    2016-11-01

    Waste activated sludge (WAS) requires a long digestion time because of a rate-limiting hydrolysis step - the first phase of anaerobic digestion (AD). Pretreatment can be used prior to AD to facilitate the hydrolysis step and improve the efficiency of WAS digestion. This study evaluated a novel application of electrochemical (EC) technology employed as the pretreatment method prior to AD of WAS, focusing on the effect of process conditions on sludge disintegration and subsequent AD process. A superior process condition of EC pretreatment was obtained by reaction time of 30 min, electrolysis voltage of 20 V, and electrode distance of 5 cm, under which the disintegration degree of WAS ranged between 9.02% and 9.72%. In the subsequent batch AD tests, 206 mL/g volatile solid (VS) methane production in EC pretreated sludge was obtained, which was 20.47% higher than that of unpretreated sludge. The AD time was 19 days shorter for EC pretreated sludge compared to the unpretreated sludge. Additionally, the EC + AD reactor achieved 41.84% of VS removal at the end of AD. The analysis of energy consumption showed that EC pretreatment could be effective in enhancing sludge AD with reduced energy consumption when compared to other pretreatment methods.

  20. Process Improvements to Biomass Pretreatment of Fuels and Chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Teymouri, Farzaneh [Michigan Biotechnology Inst., Lansing, MI (United States)

    2015-05-30

    MBI, a 501c(3) company focusing on de-risking and scaling up bio-based technologies, has teamed with Michigan State University and the Idaho National Laboratory to develop and demonstrate process improvements to the ammonia fiber expansion (AFEX) pretreatment process. The logistical hurdles of biomass handling are well known, and the regional depot concept - in which small, distributed bioprocessing operations collect, preprocess, and densify biomass before shipping to a centralized refinery - is a promising alternative to centralized collection. AFEXTM (AFEX is a trademark of MBI) has unique features among pretreatments that would make it desirable as a pretreatment prior to densification at the depot scale. MBI has developed a novel design, using a packed bed reactor for the AFEX process that can be scaled down economically to the depot scale at a lower capital cost as compared to the traditional design (Pandia type reactor). Thus, the purpose of this project was to develop, scale-up, demonstrate, and improve this novel design The key challenges are the recovery of ammonia, consistent and complete pretreatment performance, and the overall throughput of the reactor. In this project an engineering scale packed bed AFEX system with 1-ton per day capacity was installed at MBI’s building. The system has been operational since mid-2013. During that time, MBI has demonstrated the robustness, reliability, and consistency of the process. To date, nearly 500 runs have been performed in the reactors. There have been no incidences of plugging (i.e., inability to remove ammonia from biomass after the treatment), nor has there been any instance of a major ammonia release into the atmosphere. Likewise, the sugar released via enzyme hydrolysis has remained consistent throughout these runs. Our economic model shows a 46% reduction in AFEX capital cost at the 100 ton/day scale compared to the traditional design of AFEX (Pandia type reactor). The key performance factors were

  1. Pretreatment Technologies of Lignocellulosic Materials in Bioethanol Production Process

    Directory of Open Access Journals (Sweden)

    Mohamad Rusdi Hidayat

    2013-06-01

    Full Text Available Bioethanol is one type of biofuel that developed significantly. The utilization of bioethanol is not only limited for fuel, but also could be used as material for various industries such as pharmaceuticals, cosmetics, and food. With wide utilization and relatively simple production technology has made bioethanol as the most favored biofuel currently. The use of lignocellulosic biomass, microalgae, seaweeds, even GMO (Genetically modified organisms as substrates for bioethanol production has been widely tested. Differences in the materials eventually led to change in the production technology used. Pretreatment technology in the bioethanol production using lignocellulosic currently experiencing rapid development. It is a key process and crucial for the whole next steps. Based on the advantages and disadvantages from all methods, steam explotion and liquid hot water methods are the most promising  pretreatment technology available.

  2. Validation Testing of the Nitric Acid Dissolution Step Within the K Basin Sludge Pretreatment Process

    International Nuclear Information System (INIS)

    AJ Schmidt; CH Delegard; KL Silvers; PR Bredt; CD Carlson; EW Hoppe; JC Hayes; DE Rinehart; SR Gano; BM Thornton

    1999-01-01

    The work described in this report involved comprehensive bench-scale testing of nitric acid (HNO 3 ) dissolution of actual sludge materials from the Hanford K East (KE) Basin to confirm the baseline chemical pretreatment process. In addition, process monitoring and material balance information was collected to support the development and refinement of process flow diagrams. The testing was performed by Pacific Northwest National Laboratory (PNNL)for the US Department of Energy's Office of Spent Fuel Stabilization (EM-67) and Numatec Hanford Corporation (NHC) to assist in the development of the K Basin Sludge Pretreatment Process. The baseline chemical pretreatment process for K Basin sludge is nitric acid dissolution of all particulate material passing a 1/4-in. screen. The acid-insoluble fraction (residual solids) will be stabilized (possibly by chemical leaching/rinsing and grouting), packaged, and transferred to the Hanford Environmental Restoration Disposal Facility (ERDF). The liquid fraction is to be diluted with depleted uranium for uranium criticality safety and iron nitrate for plutonium criticality safety, and neutralized with sodium hydroxide. The liquid fraction and associated precipitates are to be stored in the Hanford Tank Waste Remediation Systems (TWRS) pending vitrification. It is expected that most of the polychlorinated biphenyls (PCBs), associated with some K Basin sludges, will remain with the residual solids for ultimate disposal to ERDF. Filtration and precipitation during the neutralization step will further remove trace quantities of PCBs within the liquid fraction. The purpose of the work discussed in this report was to examine the dissolution behavior of actual KE Basin sludge materials at baseline flowsheet conditions and validate the.dissolution process step through bench-scale testing. The progress of the dissolution was evaluated by measuring the solution electrical conductivity and concentrations of key species in the dissolver

  3. Validation Testing of the Nitric Acid Dissolution Step Within the K Basin Sludge Pretreatment Process

    Energy Technology Data Exchange (ETDEWEB)

    AJ Schmidt; CH Delegard; KL Silvers; PR Bredt; CD Carlson; EW Hoppe; JC Hayes; DE Rinehart; SR Gano; BM Thornton

    1999-03-24

    The work described in this report involved comprehensive bench-scale testing of nitric acid (HNO{sub 3}) dissolution of actual sludge materials from the Hanford K East (KE) Basin to confirm the baseline chemical pretreatment process. In addition, process monitoring and material balance information was collected to support the development and refinement of process flow diagrams. The testing was performed by Pacific Northwest National Laboratory (PNNL)for the US Department of Energy's Office of Spent Fuel Stabilization (EM-67) and Numatec Hanford Corporation (NHC) to assist in the development of the K Basin Sludge Pretreatment Process. The baseline chemical pretreatment process for K Basin sludge is nitric acid dissolution of all particulate material passing a 1/4-in. screen. The acid-insoluble fraction (residual solids) will be stabilized (possibly by chemical leaching/rinsing and grouting), packaged, and transferred to the Hanford Environmental Restoration Disposal Facility (ERDF). The liquid fraction is to be diluted with depleted uranium for uranium criticality safety and iron nitrate for plutonium criticality safety, and neutralized with sodium hydroxide. The liquid fraction and associated precipitates are to be stored in the Hanford Tank Waste Remediation Systems (TWRS) pending vitrification. It is expected that most of the polychlorinated biphenyls (PCBs), associated with some K Basin sludges, will remain with the residual solids for ultimate disposal to ERDF. Filtration and precipitation during the neutralization step will further remove trace quantities of PCBs within the liquid fraction. The purpose of the work discussed in this report was to examine the dissolution behavior of actual KE Basin sludge materials at baseline flowsheet conditions and validate the.dissolution process step through bench-scale testing. The progress of the dissolution was evaluated by measuring the solution electrical conductivity and concentrations of key species in the

  4. UV/H2O2 process performance improvement by ultrafiltration and physicochemical clarification systems for industrial effluent pretreatment

    Directory of Open Access Journals (Sweden)

    Ivanildo Hespanhol

    2012-12-01

    Full Text Available The present study evaluated the removal of TOC from an effluent with high organic load resulted from the treatment of oil-water emulsion by thermal process. Hollow Fiber Ultrafiltration membrane (HF-UF and physicochemical clarification process were used as pretreatment options to assess the influence of feed effluent quality on the UV/H2O2 oxidation process. Results for TOC removals showed HF-UF and physicochemical clarification processes can significantly improve the efficiency of UV/H2O2 oxidation process, when compared with the direct effluent oxidation. Reaction time for obtaining a TOC removal higher than 90% was reduced to approximately half of the time needed when no pretreatment was applied. Considering both pretreatment processes it was not possible to notice any significant difference on the UV/H2O2 oxidation process performance. However, the complexity of physicochemical process due to the use of three different chemicals and sludge production made the HF-UF process the best pretreatment alternative, without increasing the Total Dissolved Solids of the effluent, a very important issue when water reuse is considered.

  5. Techno-economic comparison of centralized versus decentralized biorefineries for two alkaline pretreatment processes.

    Science.gov (United States)

    Stoklosa, Ryan J; Del Pilar Orjuela, Andrea; da Costa Sousa, Leonardo; Uppugundla, Nirmal; Williams, Daniel L; Dale, Bruce E; Hodge, David B; Balan, Venkatesh

    2017-02-01

    In this work, corn stover subjected to ammonia fiber expansion (AFEX™) 1 pretreatment or alkaline pre-extraction followed by hydrogen peroxide post-treatment (AHP pretreatment) were compared for their enzymatic hydrolysis yields over a range of solids loadings, enzymes loadings, and enzyme combinations. Process techno-economic models were compared for cellulosic ethanol production for a biorefinery that handles 2000tons per day of corn stover employing a centralized biorefinery approach with AHP or a de-centralized AFEX pretreatment followed by biomass densification feeding a centralized biorefinery. A techno-economic analysis (TEA) of these scenarios shows that the AFEX process resulted in the highest capital investment but also has the lowest minimum ethanol selling price (MESP) at $2.09/gal, primarily due to good energy integration and an efficient ammonia recovery system. The economics of AHP could be made more competitive if oxidant loadings were reduced and the alkali and sugar losses were also decreased. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Pretreatment of whole blood using hydrogen peroxide and UV irradiation. Design of the advanced oxidation process.

    Science.gov (United States)

    Bragg, Stefanie A; Armstrong, Kristie C; Xue, Zi-Ling

    2012-08-15

    A new process to pretreat blood samples has been developed. This process combines the Advanced Oxidation Process (AOP) treatment (using H(2)O(2) and UV irradiation) with acid deactivation of the enzyme catalase in blood. A four-cell reactor has been designed and built in house. The effect of pH on the AOP process has been investigated. The kinetics of the pretreatment process shows that at high C(H(2)O(2),t=0), the reaction is zeroth order with respect to C(H(2)O(2)) and first order with respect to C(blood). The rate limiting process is photon flux from the UV lamp. Degradation of whole blood has been compared with that of pure hemoglobin samples. The AOP pretreatment of the blood samples has led to the subsequent determination of chromium and zinc concentrations in the samples using electrochemical methods. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Integrating pretreatment and retrieval: Results from the July 1997 Tanks Focus Area workshop

    International Nuclear Information System (INIS)

    1998-07-01

    If scientists and researchers working to solve the tank waste challenges, technical program office managers at the tank sites, and others understand the connection between retrieval and pretreatment activities, more efficient processes and reduced costs can be achieved. To make this possible, researchers involved in retrieval and pretreatment activities met at the Conference Center in Richland, Washington, on July 16 and 17, 1997, to discuss the connections between these activities. The purpose of the workshop was to help participants (1) gain a better understanding of retrieval and pretreatment process needs and experiences; (2) gain practical knowledge of the applications, capabilities, and requirements of retrieval and pretreatment technologies being developed and deployed; and (3) focus on identifying and troubleshooting interface issues and problems. The end product of this meeting was to create a checklist of retrieval and pretreatment parameters to consider when developing new technologies or managing work at the sites in these areas. For convenience, the information is also organized by pretreatment parameter and retrieval-pretreatment parameter in Section 5.0

  8. Distillation as a pretreatment process of waste scintillation solutions

    International Nuclear Information System (INIS)

    Dellamano, J.C.

    1988-05-01

    A process to pretreat scintillation solutions composed basically of PPO, POPOP, TOLUENE and ANTAROX, utilized by radioimmunoassay laboratories, is described. The technique employed is distillation which permits a waste reduction to about 40% of the initial volume with the recovery of the solvent (toluene). The recovered toluene can be resued for the same purpose, since it is free of radioactive material as assured by quality control procedures. (author) [pt

  9. Effects of chemical-physical pre-treatment processes on hemp fibres for reinforcement of composites and textiles

    DEFF Research Database (Denmark)

    Thomsen, Anne Belinda; Thygesen, Anders; Bohn, Vibeke

    2006-01-01

    Retted hemp fibres were treated using chemical-physical pre-treatments and the material was characterised chemically in order to evaluate the effect of the pre-treatments, respectively, wet oxidation (WO), hydrothermal treatment (HT) and steam explosion (STEX). Process variables were addition...

  10. [Statistical process control applied to intensity modulated radiotherapy pretreatment controls with portal dosimetry].

    Science.gov (United States)

    Villani, N; Gérard, K; Marchesi, V; Huger, S; François, P; Noël, A

    2010-06-01

    The first purpose of this study was to illustrate the contribution of statistical process control for a better security in intensity modulated radiotherapy (IMRT) treatments. This improvement is possible by controlling the dose delivery process, characterized by pretreatment quality control results. So, it is necessary to put under control portal dosimetry measurements (currently, the ionisation chamber measurements were already monitored by statistical process control thanks to statistical process control tools). The second objective was to state whether it is possible to substitute ionisation chamber with portal dosimetry in order to optimize time devoted to pretreatment quality control. At Alexis-Vautrin center, pretreatment quality controls in IMRT for prostate and head and neck treatments were performed for each beam of each patient. These controls were made with an ionisation chamber, which is the reference detector for the absolute dose measurement, and with portal dosimetry for the verification of dose distribution. Statistical process control is a statistical analysis method, coming from industry, used to control and improve the studied process quality. It uses graphic tools as control maps to follow-up process, warning the operator in case of failure, and quantitative tools to evaluate the process toward its ability to respect guidelines: this is the capability study. The study was performed on 450 head and neck beams and on 100 prostate beams. Control charts, showing drifts, both slow and weak, and also both strong and fast, of mean and standard deviation have been established and have shown special cause introduced (manual shift of the leaf gap of the multileaf collimator). Correlation between dose measured at one point, given with the EPID and the ionisation chamber has been evaluated at more than 97% and disagreement cases between the two measurements were identified. The study allowed to demonstrate the feasibility to reduce the time devoted to

  11. Statistical process control applied to intensity modulated radiotherapy pretreatment controls with portal dosimetry

    International Nuclear Information System (INIS)

    Villani, N.; Noel, A.; Villani, N.; Gerard, K.; Marchesi, V.; Huger, S.; Noel, A.; Francois, P.

    2010-01-01

    Purpose The first purpose of this study was to illustrate the contribution of statistical process control for a better security in intensity modulated radiotherapy (I.M.R.T.) treatments. This improvement is possible by controlling the dose delivery process, characterized by pretreatment quality control results. So, it is necessary to put under control portal dosimetry measurements (currently, the ionisation chamber measurements were already monitored by statistical process control thanks to statistical process control tools). The second objective was to state whether it is possible to substitute ionisation chamber with portal dosimetry in order to optimize time devoted to pretreatment quality control. Patients and methods At Alexis-Vautrin center, pretreatment quality controls in I.M.R.T. for prostate and head and neck treatments were performed for each beam of each patient. These controls were made with an ionisation chamber, which is the reference detector for the absolute dose measurement, and with portal dosimetry for the verification of dose distribution. Statistical process control is a statistical analysis method, coming from industry, used to control and improve the studied process quality. It uses graphic tools as control maps to follow-up process, warning the operator in case of failure, and quantitative tools to evaluate the process toward its ability to respect guidelines: this is the capability study. The study was performed on 450 head and neck beams and on 100 prostate beams. Results Control charts, showing drifts, both slow and weak, and also both strong and fast, of mean and standard deviation have been established and have shown special cause introduced (manual shift of the leaf gap of the multi-leaf collimator). Correlation between dose measured at one point, given with the E.P.I.D. and the ionisation chamber has been evaluated at more than 97% and disagreement cases between the two measurements were identified. Conclusion The study allowed to

  12. Synergistic effect of pretreatment and fermentation process on carbohydrate-rich Scenedesmus dimorphus for bioethanol production

    International Nuclear Information System (INIS)

    Chng, Lee Muei; Lee, Keat Teong; Chan, Derek Juinn Chieh

    2017-01-01

    Highlights: • Biomass of Scenedesmus dimorphus is degradable to produce fermentable sugar. • Sugar yield improves with acidic, enzymatic and organosolv pretreatment. • Pretreatment strategies are positively correlated with fermentation process. • SSF with organosolv-treated biomass is promising for bioethanol production. - Abstract: Significant development in conversion technologies to produce bioethanol from microalgae biomass is causing paradigm-shift in energy management. In this study, carbohydrate-rich microalgae, Scenedesmus dimorphus (49% w/w of carbohydrate) is selected with the aim to obtain qualitative correlation between pretreatment and fermentation process. In view of this, separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) were conducted experimentally. The fermentation behavior were investigated for microalgae biomass treated via organosolv, enzymatic and acidic pretreatment. Fermentation process was carried out by ethanologen microbe, Saccharomyces cerevisiae. From the result, it is observed that a combination of two treatment is found to be the most effective in producing fermentable sugar for the subsequent fermentation process. The organosolv treatment which is followed with the SSF process produced a theoretical yield of bioethanol that exceeded 90%. On the other hand, hydrothermal acid-hydrolyzed fermentation produced the bioethanol yield with 80% of its theoretical yield. Enzymatic-hydrolyzed SHF produced 84% of theoretical yield at longer reaction time compared with others. The results were obtained with constant fermentation parameters conducted at pH 5, temperature of 34 °C, and microalgae biomass loading at 18 g/L. Ultimately, the coupling of organosolv-treated biomass with SSF process is found to be the most cost-effective for S. dimorphus biomass as bioethanol feedstock.

  13. Livestock Feed Production from Sago Solid Waste by Pretreatment and Anaerobic Fermentation Process

    Directory of Open Access Journals (Sweden)

    Sumardiono Siswo

    2018-01-01

    Full Text Available Food needs in Indonesia is increasing, including beef. Today, Indonesia has problem to do self-sufficiency in beef. The cause of the problem is the quality of local beef is still lower compared with imported beef due to the quality of livestock feed consumed. To increase the quality of livestock is through pretreatment and fermentation. Source of livestock feed that processed is solid sago waste (Arenga microcarpa, because in Indonesia that is relatively abundant and not used optimally. Chemical pretreatment process for delignification is by using NaOH solution. The purposes of this research are to study NaOH pretreatment, the addition of Trichoderma sp, and fermentation time to improve the quality of sago solid waste as livestock feed through anaerobic fermentation. The variables used are addition or without addition (4%w NaOH solution and Trichoderma sp 1%w and fermentation time (7, 14 and 21 days, with the response of crude fiber and protein. The result of this research shows that the pretreatment with soaking of NaOH solution, addition of Trichoderma sp and 14 days of fermentation was more effective to improve the quality of solid sago waste with decrease of crude fiber from 33.37% to 17.36% and increase of crude protein from 4.00% to 7.96%.

  14. Removal of oil pollutants in seawater as pretreatment of reverse osmosis desalination process

    Energy Technology Data Exchange (ETDEWEB)

    Wen Jian; Nishijima, Wataru; Baes, Aloysius U.; Okada, Mitsumasa [Hiroshima Univ., Environmental Science Dept., Hiroshima (Japan); Kitanaka, Atsushi [Fuji-Electric Corporate Research and Development Ltd., Yokosuka, Kanagawa (Japan)

    1999-11-01

    Weathered oil contaminated seawater (WOCS) was used to investigate the behaviour of soluble oil components in seawater in various pretreatment processes for removal of oil pollutants in seawater. The various pretreatment processes were a reverse osmosis desalination process in combination with advanced oxidation processes, ultrafiltration, coagulation, GAC adsorption, biological treatment and separation with a low pressure RO membrane. WOCS was prepared by mixing oil, nutrients and fresh seawater which was exposed to sunlight to simulate photooxidation and microbial degradation of oil in the marine environment. It was found that WOCS contained soluble components with relatively small molecular size, which are refractory to biodegradation and difficult to remove by advanced oxidation processes (AOPs), UF membrane or coagulation using FeCl{sub 3} or PAC as flocculants. However, DOC in WOCS (OCWOCS) was easily adsorbed to GAC. Low pressure RO membranes with higher salt rejection rate could remove more OCWOCS compared to those of lower salt rejection rate. (Author)

  15. Removal of oil pollutants in seawater as pretreatment of reverse osmosis desalination process

    Energy Technology Data Exchange (ETDEWEB)

    Wen Jian; Nishijima, Wataru; Baes, Aloysius U.; Okada, Mitsumasa [Hiroshima Univ., Environmental Science Dept., Hiroshima (Japan); Kitanaka, Atsushi [Fuji-Electric Corporate Research and Development Ltd., Yokosuka, Kanagawa (Japan)

    1999-07-01

    Weathered oil contaminated seawater (WOCS) was used to investigate the behaviour of soluble oil components in seawater in various pretreatment processes for removal of oil pollutants in seawater. The various pretreatment processes were a reverse osmosis desalination process in combination with advanced oxidation processes, ultrafiltration, coagulation, GAC adsorption, biological treatment and separation with a low pressure RO membrane. WOCS was prepared by mixing oil, nutrients and fresh seawater which was exposed to sunlight to simulate photooxidation and microbial degradation of oil in the marine environment. It was found that WOCS contained soluble components with relatively small molecular size, which are refractory to biodegradation and difficult to remove by advanced oxidation processes (AOPs), UF membrane or coagulation using FeCl{sub 3} or PAC as flocculants. However, DOC in WOCS (OCWOCS) was easily adsorbed to GAC. Low pressure RO membranes with higher salt rejection rate could remove more OCWOCS compared to those of lower salt rejection rate. (Author)

  16. Pretreatment status report on the identification and evaluation of alternative processes

    International Nuclear Information System (INIS)

    Sutherland, D.G.; Brothers, A.J.; Beary, M.M.; Nicholson, G.A.

    1993-09-01

    The purpose of this report is to support the development and demonstration of a pretreatment system that will (1) destroy organic materials and ferrocyanide in tank wastes so that the wastes can be stored safely, (2) separate the high-activity and low-activity fractions, (3) remove radionuclides and remove or destroy hazardous chemicals in LLW as necessary to meet waste form feed requirements, (4) support development and demonstration of vitrification technology by providing representative feeds to the bench-scale glass melter, (5) support full-scale HLW vitrification operations, including near-term operation, by providing feed that meets specifications, and (6) design and develop pretreatment processes that accomplish the above objectives and ensure compliance with environmental regulations. This report is a presentation of candidate technologies for pretreatment of Hanford Site tank waste. Included are descriptions of studies by the Pacific Northwest Laboratory of Battelle Memorial Institute; Science Applications International Corporation, an independent consultant; BNFL, Inc. representing British technologies; Numatec, representing French technologies; and brief accounts of other relevant activities

  17. Investigations involving oxidation-reduction (REDOX) pretreatment in conjunction with biological remediation of contaminated soils

    International Nuclear Information System (INIS)

    Montemagno, C.D.; Peters, R.W.; Tyree, A.

    1991-01-01

    Oxidation-reduction (REDOX) reactions are among the most important reactions involved in the environmental engineering field. Oxidation is a reaction in which the oxidation state of the treated compound is increased, i.e., the material loses electrons. Reduction involves the addition of a chemical (reducing) agent which lowers the oxidation state of a substance, i.e., the material gains electrons. Both processes of oxidation and reduction occur together. All REDOX reactions are thermodynamically based. There are a number of oxidizing agents which have been reported in the technical literature for treatment of refractory organic compounds. Common oxidizing agents include: hydrogen peroxide, ozone, ultraviolet (UV) irradiation, and combinations thereof, such as UV/ozone and UV/peroxide. A gradient of REDOX reactions is possible, depending on such factors as the oxidation-reduction reaction conditions, the availability of electron donors and acceptors, and the nature of the organic compounds involved. A review of the technical literature revealed that the majority of the oxidation-reduction applications have been in the areas of wastewater treatment and groundwater remediation, with very little attention devoted to the potential of using REDOX technologies for remediation of hydrocarbon contaminated soils. In this particular study, feasibility studies were performed on gasoline- contaminated soil. These studies focused on three major phases: 1) containment of the contamination by addition of tailoring agents to the soil, 2) biological remediation either performed in situ or on-site (using a slurry reactor system), and 3) pretreatment of the contaminated soils using REDOX systems, prior to biological remediation. This particular paper focuses on the third phase of the project, aimed at ''softening'' the refractory organics resulting in the formation of organic compounds which are more amenable to biological degradation. This paper focuses its attention on the use of

  18. Investigations involving oxidation-reduction (REDOX) pretreatment in conjunction with biological remediation of contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Montemagno, C. D. [Argonne National Laboratory, Argonne, IL (United States); Peters, R. W.; Tyree, A.

    1991-07-01

    Oxidation-reduction (REDOX) reactions are among the most important reactions involved in the environmental engineering field. Oxidation is a reaction in which the oxidation state of the treated compound is increased, i.e., the material loses electrons. Reduction involves the addition of a chemical (reducing) agent which lowers the oxidation state of a substance, i.e., the material gains electrons. Both processes of oxidation and reduction occur together. All REDOX reactions are thermodynamically based. There are a number of oxidizing agents which have been reported in the technical literature for treatment of refractory organic compounds. Common oxidizing agents include: hydrogen peroxide, ozone, ultraviolet (UV) irradiation, and combinations thereof, such as UV/ozone and UV/peroxide. A gradient of REDOX reactions is possible, depending on such factors as the oxidation-reduction reaction conditions, the availability of electron donors and acceptors, and the nature of the organic compounds involved. A review of the technical literature revealed that the majority of the oxidation-reduction applications have been in the areas of wastewater treatment and groundwater remediation, with very little attention devoted to the potential of using REDOX technologies for remediation of hydrocarbon contaminated soils. In this particular study, feasibility studies were performed on gasoline- contaminated soil. These studies focused on three major phases: 1) containment of the contamination by addition of tailoring agents to the soil, 2) biological remediation either performed in situ or on-site (using a slurry reactor system), and 3) pretreatment of the contaminated soils using REDOX systems, prior to biological remediation. This particular paper focuses on the third phase of the project, aimed at ''softening'' the refractory organics resulting in the formation of organic compounds which are more amenable to biological degradation. This paper focuses its attention on the use of

  19. Lignocellulosic Biomass Pretreatment Using AFEX

    Science.gov (United States)

    Balan, Venkatesh; Bals, Bryan; Chundawat, Shishir P. S.; Marshall, Derek; Dale, Bruce E.

    Although cellulose is the most abundant organic molecule, its susceptibility to hydrolysis is restricted due to the rigid lignin and hemicellulose protection surrounding the cellulose micro fibrils. Therefore, an effective pretreatment is necessary to liberate the cellulose from the lignin-hemicellulose seal and also reduce cellulosic crystallinity. Some of the available pretreatment techniques include acid hydrolysis, steam explosion, ammonia fiber expansion (AFEX), alkaline wet oxidation, and hot water pretreatment. Besides reducing lignocellulosic recalcitrance, an ideal pretreatment must also minimize formation of degradation products that inhibit subsequent hydrolysis and fermentation. AFEX is an important pretreatment technology that utilizes both physical (high temperature and pressure) and chemical (ammonia) processes to achieve effective pretreatment. Besides increasing the surface accessibility for hydrolysis, AFEX promotes cellulose decrystallization and partial hemicellulose depolymerization and reduces the lignin recalcitrance in the treated biomass. Theoretical glucose yield upon optimal enzymatic hydrolysis on AFEX-treated corn stover is approximately 98%. Furthermore, AFEX offers several unique advantages over other pretreatments, which include near complete recovery of the pretreatment chemical (ammonia), nutrient addition for microbial growth through the remaining ammonia on pretreated biomass, and not requiring a washing step during the process which facilitates high solid loading hydrolysis. This chapter provides a detailed practical procedure to perform AFEX, design the reactor, determine the mass balances, and conduct the process safely.

  20. Development of a pyro-partitioning process for long-lived radioactive nuclides. Process test for pretreatment of simulated high-level waste containing uranium

    International Nuclear Information System (INIS)

    Kurata, Masateru; Hijikata, Takatoshi; Kinoshita, Kensuke; Inoue, Tadashi

    2000-01-01

    A pyro-partitioning process developed at CRIEPI requires a pre-treatment process to convert high-level liquid waste to chloride. A combination process of denitration and chlorination has been developed for this purpose. Continuous process tests using simulated high-level waste were performed to certify the applicability of the process. Test results indicated a successful material balance sufficient for satisfying pyro-partitioning process criteria. In the present study, process tests using simulated high-level waste containing uranium were also carried out to prove that the pre-treatment process is feasible for uranium. The results indicated that uranium can be converted to chloride appropriate for the pyro-partitioning process. The material balance obtained from the tests is to be used to revise the process flow diagram. (author)

  1. Multivariate analysis of sludge disintegration by microwave–hydrogen peroxide pretreatment process

    International Nuclear Information System (INIS)

    Ya-wei, Wang; Cheng-min, Gui; Xiao-tang, Ni; Mei-xue, Chen; Yuan-song, Wei

    2015-01-01

    Highlights: • Investigation of TSS, H 2 O 2 dosage, pH and interactions on MW sludge pretreatment. • Quadratic models were drawn for 16 response variables with good predictive ability. • Models could optimize the treatment process for multiple disintegration objectives. - Abstract: Microwave irradiation (with H 2 O 2 ) has been shown to offer considerable advantages owing to its flexible control, low overall cost, and resulting higher soluble chemical oxygen demand (SCOD); accordingly, the method has been proposed recently as a means of improving sludge disintegration. However, the key factor controlling this sludge pretreatment process, pH, has received insufficient attention to date. To address this, the response surface approach (central composite design) was applied to evaluate the effects of total suspended solids (TSS, 2–20 g/L), pH (4–10), and H 2 O 2 dosage (0–2 w/w) and their interactions on 16 response variables (e.g., SCOD released , pH, H 2 O 2remaining ). The results demonstrated that all three factors affect sludge disintegration significantly, and no pronounced interactions between response variables were observed during disintegration, except for three variables (TCOD, TSS remaining , and H 2 O 2 remaining ). Quadratic predictive models were constructed for all 16 response variables (R 2 : 0.871–0.991). Taking soluble chemical oxygen demand (SCOD) as an example, the model and coefficients derived above were able to predict the performance of microwave pretreatment (enhanced by H 2 O 2 and pH adjustment) from previously published studies. The predictive models developed were able to optimize the treatment process for multiple disintegration objectives

  2. The Effect of Pretreatments on Surfactin Production From Potato Process Effluent by Bacillus Subtilis

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, David Neal; Fox, Sandra Lynn; Bala, Greg Alan

    2000-05-01

    Pretreatment of low-solids (LS) potato process effluent was tested for potential to increase surfactin yield. Pretreatments included heat, removal of starch particulates, and acid hydrolysis. Elimination of contaminating vegetative cells was necessary for surfactin production. After autoclaving, 0.40 g/L of surfactin was produced from the effluent in 72 h, versus 0.24 g/L in the purified potato starch control. However, surfactin yields per carbon consumed were 76% lower from process effluent. Removal of starch particulates had little effect on the culture. Acid hydrolysis decreased growth and surfactant production, except 0.5 wt% acid, which increased the yield by 25% over untreated effluent.

  3. The effect of pretreatments on surfactin production from potato process effluent by Bacillus subtilis

    Energy Technology Data Exchange (ETDEWEB)

    D. N. Thompson; S. L. Fox; G. A. Bala

    2000-05-07

    Pretreatment of low-solids (LS) potato process effluent was tested for potential to increase surfactin yield. Pretreatments included heat, removal of starch particulates, and acid hydrolysis. Elimination of contaminating vegetative cells was necessary for surfactin production. After autoclaving, 0.40 g/L of surfactin was produced from the effluent in 72 h, versus 0.24 g/L in the purified potato starch control. However, surfactin yields per carbon consumed were 76% lower from process effluent. Removal of starch particulates had little effect on the culture. Acid hydrolysis decreased growth and surfactant production, except 0.5 wt% acid, which increased the yield by 25% over untreated effluent.

  4. Performance and techno-economic assessment of several solid-liquid separation technologies for processing dilute-acid pretreated corn stover.

    Science.gov (United States)

    Sievers, David A; Tao, Ling; Schell, Daniel J

    2014-09-01

    Solid-liquid separation of pretreated lignocellulosic biomass slurries is a critical unit operation employed in several different processes for production of fuels and chemicals. An effective separation process achieves good recovery of solute (sugars) and efficient dewatering of the biomass slurry. Dilute acid pretreated corn stover slurries were subjected to pressure and vacuum filtration and basket centrifugation to evaluate the technical and economic merits of these technologies. Experimental performance results were used to perform detailed process simulations and economic analysis using a 2000 tonne/day biorefinery model to determine differences between the various filtration methods and their process settings. The filtration processes were able to successfully separate pretreated slurries into liquor and solid fractions with estimated sugar recoveries of at least 95% using a cake washing process. A continuous vacuum belt filter produced the most favorable process economics. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Enzymatic saccharification and bioethanol production from Cynara cardunculus pretreated by steam explosion.

    Science.gov (United States)

    Fernandes, Maria C; Ferro, Miguel D; Paulino, Ana F C; Mendes, Joana A S; Gravitis, Janis; Evtuguin, Dmitry V; Xavier, Ana M R B

    2015-06-01

    The correct choice of the specific lignocellulosic biomass pretreatment allows obtaining high biomass conversions for biorefinery implementations and cellulosic bioethanol production from renewable resources. Cynara cardunculus (cardoon) pretreated by steam explosion (SE) was involved in second-generation bioethanol production using separate hydrolysis and fermentation (SHF) or simultaneous saccharification and fermentation (SSF) processes. Steam explosion pretreatment led to partial solubilisation of hemicelluloses and increased the accessibility of residual polysaccharides towards enzymatic hydrolysis revealing 64% of sugars yield against 11% from untreated plant material. Alkaline extraction after SE pretreatment of cardoon (CSEOH) promoted partial removal of degraded lignin, tannins, extractives and hemicelluloses thus allowing to double glucose concentration upon saccharification step. Bioethanol fermentation in SSF mode was faster than SHF process providing the best results: ethanol concentration 18.7 g L(-1), fermentation efficiency of 66.6% and a yield of 26.6g ethanol/100 g CSEOH or 10.1 g ethanol/100 g untreated cardoon. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. GREET Pretreatment Module

    Energy Technology Data Exchange (ETDEWEB)

    Adom, Felix K. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Han, Jeongwoo [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division

    2014-09-01

    A wide range of biofuels and biochemicals can be produced from cellulosic biomass via different pretreatment technologies that yield sugars. Process simulations of dilute acid and ammonia fiber expansion pretreatment processes and subsequent hydrolysis were developed in Aspen Plus for four lignocellulosic feedstocks (corn stover, miscanthus, switchgrass, and poplar). This processing yields sugars that can be subsequently converted to biofuels or biochemical. Material and energy consumption data from Aspen Plus were then compiled in a new Greenhouses Gases, Regulated Emissions, and Energy Use in Transportation (GREETTM) pretreatment module. The module estimates the cradle-to-gate fossil energy consumption (FEC) and greenhouse gas (GHG) emissions associated with producing fermentable sugars. This report documents the data and methodology used to develop this module and the cradle-to-gate FEC and GHG emissions that result from producing fermentable sugars.

  7. Multivariate analysis of sludge disintegration by microwave–hydrogen peroxide pretreatment process

    Energy Technology Data Exchange (ETDEWEB)

    Ya-wei, Wang; Cheng-min, Gui; Xiao-tang, Ni; Mei-xue, Chen; Yuan-song, Wei, E-mail: Yswei@rcees.ac.cn

    2015-02-11

    Highlights: • Investigation of TSS, H{sub 2}O{sub 2} dosage, pH and interactions on MW sludge pretreatment. • Quadratic models were drawn for 16 response variables with good predictive ability. • Models could optimize the treatment process for multiple disintegration objectives. - Abstract: Microwave irradiation (with H{sub 2}O{sub 2}) has been shown to offer considerable advantages owing to its flexible control, low overall cost, and resulting higher soluble chemical oxygen demand (SCOD); accordingly, the method has been proposed recently as a means of improving sludge disintegration. However, the key factor controlling this sludge pretreatment process, pH, has received insufficient attention to date. To address this, the response surface approach (central composite design) was applied to evaluate the effects of total suspended solids (TSS, 2–20 g/L), pH (4–10), and H{sub 2}O{sub 2} dosage (0–2 w/w) and their interactions on 16 response variables (e.g., SCOD{sub released}, pH, H{sub 2}O{sub 2remaining}). The results demonstrated that all three factors affect sludge disintegration significantly, and no pronounced interactions between response variables were observed during disintegration, except for three variables (TCOD, TSS{sub remaining}, and H{sub 2}O{sub 2} {sub remaining}). Quadratic predictive models were constructed for all 16 response variables (R{sup 2}: 0.871–0.991). Taking soluble chemical oxygen demand (SCOD) as an example, the model and coefficients derived above were able to predict the performance of microwave pretreatment (enhanced by H{sub 2}O{sub 2} and pH adjustment) from previously published studies. The predictive models developed were able to optimize the treatment process for multiple disintegration objectives.

  8. Application of a continuous twin screw-driven process for dilute acid pretreatment of rape straw.

    Science.gov (United States)

    Choi, Chang Ho; Oh, Kyeong Keun

    2012-04-01

    Rape straw, a processing residue generated from the bio-oil industry, was used as a model biomass for application of continuous twin screw-driven dilute acid pretreatment. The screw rotation speed and feeding rate were adjusted to 19.7rpm and 0.5g/min, respectively to maintain a residence time of 7.2min in the reaction zone, respectively. The sulfuric acid concentration was 3.5wt% and the reaction temperature was 165°C. The enzymatic digestibility of the glucan in the pretreated solids was 70.9%. The continuous process routinely gave around 28.8% higher yield for glucan digestibility than did the batch processing method. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Literature Review of Physical and Chemical Pretreatment Processes for Lignocellulosic Biomass

    Energy Technology Data Exchange (ETDEWEB)

    Harmsen, P.; Bakker, R. [Wageningen University and Research centre WUR, Food and Biobased Research WUR-FBR, Wageningen (Netherlands); Huijgen, W.J.J. [ECN Biomass, Coal and Environment, Petten (Netherlands); Bermudez Lopez, L. [Abengoa Bioenergia Nuevas Tecnologias ABNT (Spain)

    2010-09-15

    This literature review was performed within the BioSynergy project (2007-2010). BioSynergy is a European Integrated Project supported through the Sixth Framework Programme for Research and Technological Development (038994-SES6). BioSynergy stands for 'BIOmass for the market competitive and environmentally friendly SYNthesis of bio-products together with the production of secondary enERGY carriers through the biorefinery approach'. Within the BioSynergy project the overall goal of the pretreatment routes being developed is to convert raw lignocellulosic biomass into its composing sugars and lignin in a market competitive and environmentally sustainable way. This report reviews lignocellulose pretreatment in general as well as specific pretreatment technologies that are developed within the BioSynergy project including steam explosion (ABNT), mechanical/alkaline fractionation (WUR) and organosolv fractionation (ECN). In addition to these pretreatment technologies, other pretreatment technologies are studied within the BioSynergy project such as acetic/formic acid pretreatment and mild- and strong acid pretreatment.

  10. Process chemistry for the pretreatment of Hanford tank wastes

    International Nuclear Information System (INIS)

    Lumetta, G.J.; Swanson, J.L.; Barker, S.A.

    1992-08-01

    Current guidelines for disposing radioactive wastes stored in underground tanks at the US Department of Energy's Hanford Site call for the vitrification of high-level waste in borosilicate glass and disposal of the glass canisters in a deep geologic repository. Low-level waste is to be cast in grout and disposed of on site in shallow burial vaults. Because of the high cost of vitrification and geologic disposal, methods are currently being developed to minimize the volume of high-level waste requiring disposal. Two approaches are being considered for pretreating radioactive tank sludges: (1) leaching of selected components from the sludge and (2) acid dissolution of the sludge followed by separation of key radionuclides. The leaching approach offers the advantage of simplicity, but the acid dissolution/radionuclide extraction approach has the potential to produce the least number of glass canisters. Four critical components (Cr, P, S, and Al) were leached from an actual Hanford tank waste-Plutonium Finishing Plant sludge. The Al, P, and S were removed from the sludge by digestion of the sludge with 0.1 M NaOH at 100 degrees C. The Cr was leached by treating the sludge with alkaline KMnO 4 at 100 degrees C. Removing these four components from the sludge will dramatically lower the number of glass canisters required to dispose of this waste. The transuranic extraction (TRUEX) solvent extraction process has been demonstrated at a bench scale using an actual Hanford tank waste. The process, which involves extraction of the transuranic elements with octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO), separated 99.9% of the transuranic elements from the bulk components of the waste. Several problems associated with the TRUEX processing of this waste have been addressed and solved

  11. Transferring of components and energy output in industrial sewage sludge disposal by thermal pretreatment and two-phase anaerobic process.

    Science.gov (United States)

    Yang, Xiaoyi; Wang, Xin; Wang, Lei

    2010-04-01

    For a better sewage sludge disposal and more efficient energy reclamation, transforming of components and energy in sludge by thermal and WAO pretreatment followed by two-phase anaerobic UASB process were studied in the pilot scale. Biogas outputs and the qualities and quantities of the effluent and solid residue were compared with a traditional anaerobic sludge digestion. Sludge components, including carbon, nitrogen, phosphorus, sulphur, were observed and mass balances were discussed throughout the process. The input and output energy balance was also studied. Results showed different trait to compare with biogas outputs in terms of COD added and raw sludge added. Pretreatment improved the transformation of carbon substances into biogas production with higher carbon removal and higher VSS removal. Comparing the energy obtained from biogas production with energy inputs required for pretreatment, energy output in the whole process decreased with higher pretreatment temperature. Copyright 2009 Elsevier Ltd. All rights reserved.

  12. PRETREATMENT AND FRACTIONATION OF CORN STOVER BY AMMONIA RECYCLE PERCOLATION PROCESS. (R831645)

    Science.gov (United States)

    Corn stover was pretreated with aqueous ammonia in a flow-through column reactor,a process termed as Ammonia Recycle Percolation (ARP). The aqueous ammonia causesswelling and efficient delignification of biomass at high temperatures. The ARPprocess solubilizes abou...

  13. Pretreatment Solution for Water Recovery Systems

    Science.gov (United States)

    Muirhead, Dean (Inventor)

    2018-01-01

    Chemical pretreatments are used to produce usable water by treating a water source with a chemical pretreatment that contains a hexavalent chromium and an acid to generate a treated water source, wherein the concentration of sulfate compounds in the acid is negligible, and wherein the treated water source remains substantially free of precipitates after the addition of the chemical pretreatment. Other methods include reducing the pH in urine to be distilled for potable water extraction by pretreating the urine before distillation with a pretreatment solution comprising one or more acid sources selected from a group consisting of phosphoric acid, hydrochloric acid, and nitric acid, wherein the urine remains substantially precipitate free after the addition of the pretreatment solution. Another method described comprises a process for reducing precipitation in urine to be processed for water extraction by mixing the urine with a pretreatment solution comprising hexavalent chromium compound and phosphoric acid.

  14. Impacts of operating parameters on oxidation-reduction potential and pretreatment efficacy in the pretreatment of printing and dyeing wastewater by Fenton process.

    Science.gov (United States)

    Wu, Huifang; Wang, Shihe

    2012-12-01

    An experiment was conducted in a batch reactor for a real printing and dyeing wastewater pretreatment using Fenton process in this study. The results showed that original pH, hydrogen peroxide concentration and ferrous sulfate concentration affected ORP value and pretreatment efficacy greatly. Under experimental conditions, the optimal original pH was 6.61, and the optimal hydrogen peroxide and ferrous sulfate concentrations were 1.50 and 0.75 gL(-1), respectively. The relationship among ORP, original pH, hydrogen peroxide concentration, ferrous sulfate concentration, and color (COD or BOD(5)/COD) was established, which would be instructive in on-line monitoring and control of Fenton process using ORP. In addition, the effects of wastewater temperature and oxidation time on pretreatment efficacy were also investigated. With an increase of temperature, color and COD removal efficiencies and BOD(5)/COD ratio increased, and they were in proportion to the exponent of temperature reciprocal. Similarly, color and COD removal efficiencies increased with increasing oxidation time, and both color and COD removal obeyed the first-order kinetics. The BOD(5)/COD ratio could be expressed by a second-degree polynomial with respect to oxidation time, and the best biodegradability of wastewater was present at the oxidation time of 6.10h. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Degumming Pretreatment with Sodium Hydroxide and Sodium Oxalate in the Process of Whole Cotton Stalk APMP Pulping

    Directory of Open Access Journals (Sweden)

    Yu-Meng Zhao

    2015-03-01

    Full Text Available The effect of degumming pretreatment on whole cotton stalk alkaline peroxide mechanical pulp (APMP was researched. Degumming pretreatment was used as the first stage of an APMP pulping process, replacing conventional hot water pretreatment. Two degumming agents of sodium hydroxide (NaOH and sodium oxalate (Na2C2O4 were researched separately. The efficiency of hot water pretreatment, NaOH pretreatment, and Na2C2O4 pretreatment on pectin and metal ions removal was compared. After pretreatment of hot water, NaOH, and Na2C2O4, pectin content was reduced to 4.0%, 2.1%, 1.6%, respectively, compared to original material (4.3%, at removal rates of 7%, 51%, and 64%, respectively. For metal ions, especially transition metal ions, the removal rate was up to 20% after degumming pretreatment. The brightness of the handsheets was 64% ISO, 68% ISO, and 73% ISO, respectively. The dirt count was 2674 mm2•m-2, 533 mm2•m-2, and 132 mm2•m-2, respectively. After Na2C2O4 pretreatment, the tension index and tear index were increased to 40.5 N•m•g-1 and 4.5 mN•m2•g-1, respectively. Through degumming pretreatment, pectin, metal ions, and dirt count were reduced efficiently, and the brightness and physical strength were improved significantly.

  16. High-concentration sugars production from corn stover based on combined pretreatments and fed-batch process.

    Science.gov (United States)

    Yang, Maohua; Li, Wangliang; Liu, Binbin; Li, Qiang; Xing, Jianmin

    2010-07-01

    In this paper, high-concentration sugars were produced from pretreated corn stover. The raw corn stover was pretreated in a process combining steam explosion and alkaline hydrogen-peroxide. The hemicellulose and lignin were removed greatly. The cellulose content increased to 73.2%. Fed-batch enzymatic hydrolysis was initiated with 12% (w/v) solids loading and 20 FPU/g solids. Then, 6% solids were fed consecutively at 12, 36 and 60 h. After 144 h, the final concentrations of reducing sugar, glucose, cellobiose and xylose reached 220, 175, 22 and 20 g/L, respectively. The final total biomass conversion was 60% in fed-batch process. Copyright 2009 Elsevier Ltd. All rights reserved.

  17. Dynamic Modeling and Validation of a Biomass Hydrothermal Pretreatment Process - A Demonstration Scale Study

    DEFF Research Database (Denmark)

    Prunescu, Remus Mihail; Blanke, Mogens; Jakobsen, Jon Geest

    2015-01-01

    for the enzymatic hydrolysis process. Several by-products are also formed, which disturb and act as inhibitors downstream. The objective of this study is to formulate and validate a large scale hydrothermal pretreatment dynamic model based on mass and energy balances, together with a complex conversion mechanism......Hydrothermal pretreatment of lignocellulosic biomass is a cost effective technology for second generation biorefineries. The process occurs in large horizontal and pressurized thermal reactors where the biomatrix is opened under the action of steam pressure and temperature to expose cellulose...... and kinetics. The study includes a comprehensive sensitivity and uncertainty analysis, with parameter estimation from real-data in the 178-185° range. To highlight the application utility of the model, a state estimator for biomass composition is developed. The predictions capture well the dynamic trends...

  18. Possibility of content change in bioethanol gasoline during pre-treatment process for using accelerator mass spectroscopy

    International Nuclear Information System (INIS)

    Saito, Masaaki; Yunoki, Shunji; Suzuki, Takashi

    2010-01-01

    We attempted to determine the bioethanol content of E3 gasoline by applying ASTM D6866 method B. In the pre-treatment process using accelerator mass spectroscopy(AMS), the graphite samples were prepared from E3 gasoline. Three portions of the same graphite sample were measured, and the contents agreed within the measurement error of AMS. The graphite samples prepared from eight portions of the same E3 gasoline sample were measured, but the accuracy was insufficient. There are many kinds of hydrocarbon compounds in the gasoline and their boiling points are different. The content of bioethanol was found to decrease with vaporization when E3 gasoline was placed in open air. A very small amount of E3 gasoline is pre-treated for AMS and the volatile loss cannot be ignored. It seems that the content change of bioethanol was caused by vaporization of E3 gasoline during the pre-treatment process. (author)

  19. Insight into effects of electro-dewatering pretreatment on nitrous oxide emission involved in related functional genes in sewage sludge composting.

    Science.gov (United States)

    Wang, Ke; Wu, Yiqi; Wang, Zhe; Wang, Wei; Ren, Nanqi

    2018-05-26

    Electro-dewatering (ED) pretreatment could improve sludge dewatering performance and remove heavy metal, but the effect of ED pretreatment on nitrous oxide (N 2 O) emission and related functional genes in sludge composting process is still unknown, which was firstly investigated in this study. The results revealed that ED pretreatment changed the physicochemical characteristics of sludge and impacted N 2 O related functional genes, resulting in the reduction of cumulative N 2 O emission by 77.04% during 60 days composting. The higher pH and NH 4 + -N, but lower moisture, ORP and NO 2 - -N emerged in the composting of ED sludge compared to mechanical dewatering (MD) sludge. Furthermore, ED pretreatment reduced amoA, hao, narG, nirK and nosZ in ED sludge on Day-10 and Day-60 of composting. It was found that nirK reduction was the major factor impacting N 2 O generation in the initial composting of ED sludge, and the decline of amoA restricted N 2 O production in the curing period. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Methods of pretreating comminuted cellulosic material with carbonate-containing solutions

    Energy Technology Data Exchange (ETDEWEB)

    Francis, Raymond

    2012-11-06

    Methods of pretreating comminuted cellulosic material with an acidic solution and then a carbonate-containing solution to produce a pretreated cellulosic material are provided. The pretreated material may then be further treated in a pulping process, for example, a soda-anthraquinone pulping process, to produce a cellulose pulp. The pretreatment solutions may be extracted from the pretreated cellulose material and selectively re-used, for example, with acid or alkali addition, for the pretreatment solutions. The resulting cellulose pulp is characterized by having reduced lignin content and increased yield compared to prior art treatment processes.

  1. Effect of Pre-treatment method on the Hydrolysis of Corn cob and Sawdust

    Directory of Open Access Journals (Sweden)

    Olawole Ogirima Olanipekun

    2016-12-01

    Full Text Available Efficient pre-treatment has been found to be crucial step before enzymatic hydrolysis of cellulose into fuels or chemicals. As a result various pretreatment methods have been developed to facilitate these bio-conversion processes, and this research focuses on the effect of two pretreatment methods such as liquid hot water and sulphuric acid pre-treatment to remove some of the components like lignin and hemicellulose which form structural barrier to enzymatic accessibility of cellulose in corn cobs and sawdust. The cellulosic materials were first dried in oven at 65 oC for 24 hours,  and using   solid to liquid ratio of 1:10, the two methods were carried out at resident times ranging from 10 - 40 minutes. The liquid hot water method involved heating the cellulosic materials in water at 120 oC and 1atmosphere in a pressure vessel, and for the second method, the dried cellulosic materials were refluxed in 5 % sulphuric acid at a temperature of 120 oC. Pretreated samples were filtered and liquid fractions were analyzed for the presence of reducing sugars, while solid residues were dried in the oven and weighed to measure the mass lost during pretreatment as a pointer to lignin breakdown. It was observed that the mass lost increased with time for both pretreatment methods, but the liquid hot water pretreatment gave higher lignin and hemicellulose removal when compared to the sulphuric acid pre-treatment. The pretreated materials were hydrolyzed with two combinations of commercial enzymes namely cellulase/ hemicellulase and cellulase/β glucosidase. The reducing sugar was measured using Dinitrosalycilic acid (DNSA method and the sugar yields from corn cobs were higher than that of sawdust when subjected to similar process conditions, and the enzyme combination of cellulase/glucosidase gave higher yields of reducing sugars.  A model equation which describes the hydrolysis process was developed from first principles and the experimental data

  2. Pretreatment of sugarcane bagasse using the advanced oxidation process by electron beam for enzymatic hydrolysis of cellulose

    International Nuclear Information System (INIS)

    Ribeiro, Marcia Almeida

    2013-01-01

    The sugar cane bagasse is a renewable energy source and a raw material promise in the biofuel production, once represents about 30% of glucose contained in the plant with the potential to be hydrolyzed and then converted to ethanol. The bagasse is composed of cellulose, straight chain of glucose, of hemicellulose, an amorphous polymer consisting of xylose, arabinose, galactose, and mannose, and of lignin, a complex polymer consisting of fenilpropan units that acts as waterproof coating on the fibers, which is hard to remove due its recalcitrant nature. The aim of this work was to study the electron beam processing as a pretreatment of sugarcane bagasse to enzymatic hydrolysis of cellulose. The pretreatment of sugarcane bagasse is one of the most important steps to make this material economically viable and competitive on the energy production. As a pretreatment the electron beam processing can weak the hemicellulose and lignin structures by the action highly reactive radicals that breaks the links, reducing the degree of polymerization fibers. It was evaluated the chemical and structural modifications on fibers caused by the irradiation, the enzymatic hydrolysis of electron beam as the only pretreatment and combined to steam explosion. For enzymatic hydrolysis it was used the commercial enzymes from Novozymes. The radiation processing promotes changes in structure and composition of sugarcane bagasse, increasing the solubility, that is related to hemicellulose and cellulose cleavage, and also increasing the enzymatic conversion yield. In the case of exploded bagasse there is no changes in the enzymatic hydrolysis yield, however the electron beam processing promoted a 67% reduction of furfural, that is formed in the steam explosion process. (author)

  3. Overcoming the Recalcitrance for the Conversion of Kenaf Pulp to Glucose via Microwave-Assisted Pre-Treatment Processes

    Directory of Open Access Journals (Sweden)

    Miguel A. Hurtado

    2011-02-01

    Full Text Available This study evaluates the pre-treatment of cellulose from kenaf plant to yield sugar precursors for the production of ethanol or butanol for use as biofuel additives. In order to convert the crystalline cellulosic form to the amorphous form that can undergo enzymatic hydrolysis of the glycosidic bond to yield sugars, kenaf pulp samples were subjected to two different pre-treatment processes. In the acid pre-treatment, the pulp samples were treated with 37.5% hydrochloric acid in the presence of FeCl3 at 50 °C or 90 °C whereas in the alkaline method, the pulp samples were treated with 25% sodium hydroxide at room temperature and with 2% or 5% sodium hydroxide at 50 °C. Microwave-assisted NaOH-treatment of the cellulose was also investigated and demonstrated to be capable of producing high glucose yield without adverse environmental impact by circumventing the use of large amounts of concentrated acids i.e., 83–85% phosphoric acid employed in most digestion processes. The treated samples were digested with the cellulase enzyme from Trichoderma reesei. The amount of glucose produced was quantified using the QuantichromTM glucose bioassay for assessing the efficiency of glucose production for each of the treatment processes. The microwave-assisted alkaline pre-treatment processes conducted at 50 °C were found to be the most effective in the conversion of the crystalline cellulose to the amorphous form based on the significantly higher yields of sugar produced by enzymatic hydrolysis compared to the untreated sample.

  4. Hanford tank waste simulants specification and their applicability for the retrieval, pretreatment, and vitrification processes

    Energy Technology Data Exchange (ETDEWEB)

    GR Golcar; NG Colton; JG Darab; HD Smith

    2000-04-04

    A wide variety of waste simulants were developed over the past few years to test various retrieval, pretreatment and waste immobilization technologies and unit operations. Experiments can be performed cost-effectively using non-radioactive waste simulants in open laboratories. This document reviews the composition of many previously used waste simulants for remediation of tank wastes at the Hanford reservation. In this review, the simulants used in testing for the retrieval, pretreatment, and vitrification processes are compiled, and the representative chemical and physical characteristics of each simulant are specified. The retrieval and transport simulants may be useful for testing in-plant fluidic devices and in some cases for filtration technologies. The pretreatment simulants will be useful for filtration, Sr/TRU removal, and ion exchange testing. The vitrification simulants will be useful for testing melter, melter feed preparation technologies, and for waste form evaluations.

  5. Hanford tank waste simulants specification and their applicability for the retrieval, pretreatment, and vitrification processes

    International Nuclear Information System (INIS)

    GR Golcar; NG Colton; JG Darab; HD Smith

    2000-01-01

    A wide variety of waste simulants were developed over the past few years to test various retrieval, pretreatment and waste immobilization technologies and unit operations. Experiments can be performed cost-effectively using non-radioactive waste simulants in open laboratories. This document reviews the composition of many previously used waste simulants for remediation of tank wastes at the Hanford reservation. In this review, the simulants used in testing for the retrieval, pretreatment, and vitrification processes are compiled, and the representative chemical and physical characteristics of each simulant are specified. The retrieval and transport simulants may be useful for testing in-plant fluidic devices and in some cases for filtration technologies. The pretreatment simulants will be useful for filtration, Sr/TRU removal, and ion exchange testing. The vitrification simulants will be useful for testing melter, melter feed preparation technologies, and for waste form evaluations

  6. Rapid near infrared spectroscopy for prediction of enzymatic hydrolysis of corn bran after various pretreatments

    DEFF Research Database (Denmark)

    Baum, Andreas; Wittrup Agger, Jane; Meyer, Anne S.

    2012-01-01

    Efficient generation of a fermentable hydrolysate is a primary requirement in the utilization of fibrous plant biomass as feedstocks in bioethanol processes. The first biomass conversion step usually involves a hydrothermal pretreatment before enzymatic hydrolysis. The purpose of the pretreatment...... step is to increase the responsivity of the substrate to enzymatic attack and the type of pretreatment affects the enzymatic conversion efficiency. Destarched corn bran is a fibrous, heteroxylan-rich side-stream from the starch industry which may be used as a feedstock for bioethanol production...... release of different levels of arabinose, xylose and glucose from all the differently pretreated destarched corn bran samples. The present study also demonstrates a generic, non-destructive solution to determine the enzymatic monosaccharide release from polymers in biomass side-streams, thereby...

  7. Child involvement, alliance, and therapist flexibility: process variables in cognitive-behavioural therapy for anxiety disorders in childhood.

    Science.gov (United States)

    Hudson, Jennifer L; Kendall, Philip C; Chu, Brian C; Gosch, Elizabeth; Martin, Erin; Taylor, Alan; Knight, Ashleigh

    2014-01-01

    This study examined the relations between treatment process variables and child anxiety outcomes. Independent raters watched/listened to taped therapy sessions of 151 anxiety-disordered (6-14 yr-old; M = 10.71) children (43% boys) and assessed process variables (child alliance, therapist alliance, child involvement, therapist flexibility and therapist functionality) within a manual-based cognitive-behavioural treatment. Latent growth modelling examined three latent variables (intercept, slope, and quadratic) for each process variable. Child age, gender, family income and ethnicity were examined as potential antecedents. Outcome was analyzed using factorially derived clinician, mother, father, child and teacher scores from questionnaire and structured diagnostic interviews at pretreatment, posttreatment and 12-month follow-up. Latent growth models demonstrated a concave quadratic curve for child involvement and therapist flexibility over time. A predominantly linear, downward slope was observed for alliance, and functional flexibility remained consistent over time. Increased alliance, child involvement and therapist flexibility showed some albeit inconsistent, associations with positive treatment outcome. Findings support the notion that maintaining the initial high level of alliance or involvement is important for clinical improvement. There is some support that progressively increasing alliance/involvement also positively impacts on treatment outcome. These findings were not consistent across outcome measurement points or reporters. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Process performance assessment of advanced anaerobic digestion of sewage sludge including sequential ultrasound-thermal (55 °C) pre-treatment.

    Science.gov (United States)

    Neumann, Patricio; Barriga, Felipe; Álvarez, Claudia; González, Zenón; Vidal, Gladys

    2018-03-15

    The aim of this study was to evaluate the performance and digestate quality of advanced anaerobic digestion of sewage sludge including sequential ultrasound-thermal (55 °C) pre-treatment. Both stages of pre-treatment contributed to chemical oxygen demand (COD) solubilization, with an overall factor of 11.4 ± 2.2%. Pre-treatment led to 19.1, 24.0 and 29.9% increased methane yields at 30, 15 and 7.5 days solid retention times (SRT), respectively, without affecting process stability or accumulation of intermediates. Pre-treatment decreased up to 4.2% water recovery from the digestate, but SRT was a more relevant factor controlling dewatering. Advanced digestion showed 2.4-3.1 and 1.5 logarithmic removals of coliforms and coliphages, respectively, and up to a 58% increase in the concentration of inorganics in the digestate solids compared to conventional digestion. The COD balance of the process showed that the observed increase in methane production was proportional to the pre-treatment solubilization efficiency. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Ethanol production in a simultaneous saccharification and fermentation process with interconnected reactors employing hydrodynamic cavitation-pretreated sugarcane bagasse as raw material.

    Science.gov (United States)

    Terán Hilares, Ruly; Ienny, João Vitor; Marcelino, Paulo Franco; Ahmed, Muhammad Ajaz; Antunes, Felipe A F; da Silva, Silvio Silvério; Santos, Júlio César Dos

    2017-11-01

    In this study, sugarcane bagasse (SCB) pretreated with alkali assisted hydrodynamic cavitation (HC) was investigated for simultaneous saccharification and fermentation (SSF) process for bioethanol production in interconnected column reactors using immobilized Scheffersomyces stipitis NRRL-Y7124. Initially, HC was employed for the evaluation of the reagent used in alkaline pretreatment. Alkalis (NaOH, KOH, Na 2 CO 3 , Ca(OH) 2 ) and NaOH recycled black liquor (successive batches) were used and their pretreatment effectiveness was assessed considering the solid composition and its enzymatic digestibility. In SSF process using NaOH-HC pretreatment SCB, 62.33% of total carbohydrate fractions were hydrolyzed and 17.26g/L of ethanol production (0.48g of ethanol/g of glucose and xylose consumed) was achieved. This proposed scheme of HC-assisted NaOH pretreatment together with our interconnected column reactors showed to be an interesting new approach for biorefineries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Pretreatment prostate-specific antigen values in patients with prostate cancer: 1989 patterns of care study process survey

    International Nuclear Information System (INIS)

    Teshima, Teruki; Hanlon, Alexandra M.; Hanks, Gerald E.

    1995-01-01

    Purpose: A Patterns of Care Study (PCS) national survey was conducted to show the national averages for processes of radiation therapy care for prostate cancer patients in 1989. In the current study we report an analysis of pretreatment prostate-specific antigen (PSA) by stage, grade, and ethnic origin. Methods and Materials: Process data were collected from 672 patients treated in 1989 at 71 separate institutions. Four hundred and twenty-seven (64%) of these patients had a pretreatment PSA value recorded. Three hundred and forty-three of the 427 patients were treated with external beam irradiation alone and were selected for the current analysis. The 1992 AJCC staging system was used. Results: There was a significant increase in pretreatment PSA with increasing stage. The median values of PSA were 8.3 ngm/ml in the T1 group (n = 65), 11.2 ngm/ml in the T2 group (n = 178), and 20.9 ngm/ml in the T3 group (n = 90) (p < 0.001). Ten patients were not staged. There was a significant increase in pretreatment PSA with decreasing differentiation. The median pretreatment PSA was 9.7 ngm/ml in well-differentiated tumors (n = 109), 13.0 ngm/ml in moderately differentiated tumors (n = 163), and 22.0 ngm/ml in poorly differentiated tumors. (n = 61) (p < 0.001). Ten patients had no differentiation recorded. African Americans (24) showed a significant increase in pretreatment PSA compared to Caucasians (304). The respective medians were 23.2 ng/ml and 11.9 ng/ml (p = 0.04). They also show more poorly differentiated tumors (33% vs. 17%) and more T3 tumors (46% vs. 25%). Other minorities, although small in number (n = 9) were similar to African Americans. Conclusion: Pretreatment PSA levels were established for patients treated with external beam irradiation in 1989 in the United States. They increase with stage and decreasing differentiation. African Americans and other minorities show a doubling of median values compared to Caucasians' pretreatment PSA with an increase in stage

  11. Pretreatment of furfural industrial wastewater by Fenton, electro-Fenton and Fe(II)-activated peroxydisulfate processes: a comparative study.

    Science.gov (United States)

    Yang, C W; Wang, D; Tang, Q

    2014-01-01

    The Fenton, electro-Fenton and Fe(II)-activated peroxydisulfate (PDS) processes have been applied for the treatment of actual furfural industrial wastewater in this paper. Through the comparative study of the three processes, a suitable pretreatment technology for actual furfural wastewater treatment was obtained, and the mechanism and dynamics process of this technology is discussed. The experimental results show that Fenton technology has a good and stable effect without adjusting pH of furfural wastewater. At optimal conditions, which were 40 mmol/L H₂O₂ initial concentration and 10 mmol/L Fe²⁺ initial concentration, the chemical oxygen demand (COD) removal rate can reach 81.2% after 90 min reaction at 80 °C temperature. The PDS process also has a good performance. The COD removal rate could attain 80.3% when Na₂S₂O₈ initial concentration was 4.2 mmol/L, Fe²⁺ initial concentration was 0.1 mol/L, the temperature remained at 70 °C, and pH value remained at 2.0. The electro-Fenton process was not competent to deal with the high-temperature furfural industrial wastewater and only 10.2% COD was degraded at 80 °C temperature in the optimal conditions (2.25 mA/cm² current density, 4 mg/L Na₂SO₄, 0.3 m³/h aeration rate). For the Fenton, electro-Fenton and PDS processes in pretreatment of furfural wastewater, their kinetic processes follow the pseudo first order kinetics law. The pretreatment pathways of furfural wastewater degradation are also investigated in this study. The results show that furfural and furan formic acid in furfural wastewater were preferentially degraded by Fenton technology. Furfural can be degraded into low-toxicity or nontoxic compounds by Fenton pretreatment technology, which could make furfural wastewater harmless and even reusable.

  12. Multivariate analysis of sludge disintegration by microwave-hydrogen peroxide pretreatment process.

    Science.gov (United States)

    Ya-Wei, Wang; Cheng-Min, Gui; Xiao-Tang, Ni; Mei-Xue, Chen; Yuan-Song, Wei

    2015-01-01

    Microwave irradiation (with H2O2) has been shown to offer considerable advantages owing to its flexible control, low overall cost, and resulting higher soluble chemical oxygen demand (SCOD); accordingly, the method has been proposed recently as a means of improving sludge disintegration. However, the key factor controlling this sludge pretreatment process, pH, has received insufficient attention to date. To address this, the response surface approach (central composite design) was applied to evaluate the effects of total suspended solids (TSS, 2-20 g/L), pH (4-10), and H2O2 dosage (0-2 w/w) and their interactions on 16 response variables (e.g., SCODreleased, pH, H2O2remaining). The results demonstrated that all three factors affect sludge disintegration significantly, and no pronounced interactions between response variables were observed during disintegration, except for three variables (TCOD, TSSremaining, and H2O2 remaining). Quadratic predictive models were constructed for all 16 response variables (R(2): 0.871-0.991). Taking soluble chemical oxygen demand (SCOD) as an example, the model and coefficients derived above were able to predict the performance of microwave pretreatment (enhanced by H2O2 and pH adjustment) from previously published studies. The predictive models developed were able to optimize the treatment process for multiple disintegration objectives. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Urine pretreatment for waste water processing systems. [for space station

    Science.gov (United States)

    Winkler, H. E.; Verostko, C. E.; Dehner, G. F.

    1983-01-01

    Recovery of high quality water from urine is an essential part of life support on a Space Station to avoid costly launch and resupply penalties. Water can be effectively recovered from urine by distillation following pretreatment by a chemical agent to inhibit microorganism contamination and fix volatile ammonia constituents. This paper presents the results of laboratory investigations of several pretreatment chemicals which were tested at several concentration levels in combination with sulfuric acid in urine. The optimum pretreatment formulation was then evaluated with urine in the Hamilton Standard Thermoelectric Integrated Membrane Evaporation Subsystem (TIMES). Over 2600 hours of test time was accumulated. Results of these laboratory and system tests are presented in this paper.

  14. Tank Waste Remediation System tank waste pretreatment and vitrification process development testing requirements assessment

    International Nuclear Information System (INIS)

    Howden, G.F.

    1994-01-01

    A multi-faceted study was initiated in November 1993 to provide assurance that needed testing capabilities, facilities, and support infrastructure (sampling systems, casks, transportation systems, permits, etc.) would be available when needed for process and equipment development to support pretreatment and vitrification facility design and construction schedules. This first major report provides a snapshot of the known testing needs for pretreatment, low-level waste (LLW) and high-level waste (HLW) vitrification, and documents the results of a series of preliminary studies and workshops to define the issues needing resolution by cold or hot testing. Identified in this report are more than 140 Hanford Site tank waste pretreatment and LLW/HLW vitrification technology issues that can only be resolved by testing. The report also broadly characterizes the level of testing needed to resolve each issue. A second report will provide a strategy(ies) for ensuring timely test capability. Later reports will assess the capabilities of existing facilities to support needed testing and will recommend siting of the tests together with needed facility and infrastructure upgrades or additions

  15. Tank Waste Remediation System tank waste pretreatment and vitrification process development testing requirements assessment

    Energy Technology Data Exchange (ETDEWEB)

    Howden, G.F.

    1994-10-24

    A multi-faceted study was initiated in November 1993 to provide assurance that needed testing capabilities, facilities, and support infrastructure (sampling systems, casks, transportation systems, permits, etc.) would be available when needed for process and equipment development to support pretreatment and vitrification facility design and construction schedules. This first major report provides a snapshot of the known testing needs for pretreatment, low-level waste (LLW) and high-level waste (HLW) vitrification, and documents the results of a series of preliminary studies and workshops to define the issues needing resolution by cold or hot testing. Identified in this report are more than 140 Hanford Site tank waste pretreatment and LLW/HLW vitrification technology issues that can only be resolved by testing. The report also broadly characterizes the level of testing needed to resolve each issue. A second report will provide a strategy(ies) for ensuring timely test capability. Later reports will assess the capabilities of existing facilities to support needed testing and will recommend siting of the tests together with needed facility and infrastructure upgrades or additions.

  16. Pretreatment of 2,4-dinitroanisole (DNAN) producing wastewater using a combined zero-valent iron (ZVI) reduction and Fenton oxidation process

    International Nuclear Information System (INIS)

    Shen, Jinyou; Ou, Changjin; Zhou, Zongyuan; Chen, Jun; Fang, Kexiong; Sun, Xiuyun; Li, Jiansheng; Zhou, Lin; Wang, Lianjun

    2013-01-01

    Highlights: • ZVI-Fenton process was conducted for DNAN producing wastewater pretreatment. • Transformation of nitro to amino group by ZVI overcomes the oxidative hindrance. • Subsequent Fenton process is efficient for the removal of aromatic compounds. • ABR-MBBR process is efficient for the polishing of ZVI-Fenton effluent. -- Abstract: A combined zero-valent iron (ZVI) reduction and Fenton oxidation process was tested for the pretreatment of 2,4-dinitroanisole (DNAN) producing wastewater. Operating conditions were optimized and overall performance of the combined process was evaluated. For ZVI process, almost complete reduction of nitroaromatic compounds was observed at empty bed contact time (EBCT) of 8 h. For Fenton process, the optimal pH, H 2 O 2 to Fe(II) molar ratio, H 2 O 2 dosage and hydraulic retention time (HRT) were found to be 3.0, 15, 0.216 mol/L and 5 h, respectively. After pretreatment by the combined ZVI-Fenton process under the optimal conditions, aromatic organic compound removal was as high as 77.2%, while the majority of COD remained to be further treated by sequent biological process. The combined anaerobic-aerobic process consisted of an anaerobic baffled reactor (ABR) and a moving-bed biofilm reactor (MBBR) was operated for 3 months, fed with ZVI-Fenton effluent. The results revealed that the coupled ZVI-Fenton-ABR-MBBR system was significantly efficient in terms of correcting the effluent's main parameters of relevance, mainly aromatic compounds concentration, COD concentration, color and acute toxicity. These results indicate that the combined ZVI-Fenton process offers bright prospects for the pretreatment of wastewater containing nitroaromatic compounds

  17. Phosphoric acid based pretreatment of switchgrass and fermentation of entire slurry to ethanol using a simplified process.

    Science.gov (United States)

    Wu, Wei; Rondon, Vanessa; Weeks, Kalvin; Pullammanappallil, Pratap; Ingram, Lonnie O; Shanmugam, K T

    2018-03-01

    Switchgrass (Alamo) was pretreated with phosphoric acid (0.75 and 1%, w/w) at three temperatures (160, 175 and 190 °C) and time (5, 7.5 and 10 min) using a steam gun. The slurry after pretreatment was liquefied by enzymes and the released sugars were fermented in a simultaneous saccharification and co-fermentation process to ethanol using ethanologenic Escherichia coli strain SL100. Among the three variables in pretreatment, temperature and time were critical in supporting ethanol titer and yield. Enzyme hydrolysis significantly increased the concentration of furans in slurries, apparently due to release of furans bound to the solids. The highest ethanol titer of 21.2 ± 0.3 g/L ethanol obtained at the pretreatment condition of 190-1-7.5 (temperature-acid concentration-time) and 10% solids loading accounted for 190 ± 2.9 g ethanol/kg of raw switch grass. This converts to 61.7 gallons of ethanol per ton of dry switchgrass, a value that is comparable to other published pretreatment conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Factors affecting seawater-based pretreatment of lignocellulosic date palm residues

    DEFF Research Database (Denmark)

    Fang, Chuanji; Thomsen, Mette Hedegaard; Frankaer, Christian Grundahl

    2017-01-01

    Seawater-based pretreatment of lignocellulosic biomass is an innovative process at research stage. With respect to process optimization, factors affecting seawater-based pretreatment of lignocellulosic date palm residues were studied for the first time in this paper. Pretreatment temperature (180...... °C–210 °C), salinity of seawater (0 ppt–50 ppt), and catalysts (H2SO4, Na2CO3, and NaOH) were investigated. The results showed that pretreatment temperature exerted the largest influence on seawater-based pretreatment in terms of the enzymatic digestibility and fermentability of pretreated solids...

  19. Tank Focus Area pretreatment activities

    International Nuclear Information System (INIS)

    McGinnis, C.P.; Welch, T.D.; Manke, K.L.

    1997-01-01

    Plans call for the high-level wastes to be retrieved from the tanks and immobilized in a stable waste form suitable for long-term isolation. Chemistry and chemical engineering operations are required to retrieve the wastes, to condition the wastes for subsequent steps, and to reduce the costs of the waste management enterprise. Pretreatment includes those processes between retrieval and immobilization, and includes preparation of suitable feed material for immobilization and separations to partition the waste into streams that yield lower life-cycle costs. Some of the technologies being developed by the Tank Focus Area (TFA) to process these wastes are described. These technologies fall roughly into three areas: (1) solid/liquid separation (SLS), (2) sludge pretreatment, and (3) supernate pretreatment

  20. Low temperature lignocellulose pretreatment: effects and interactions of pretreatment pH are critical for maximizing enzymatic monosaccharide yields from wheat straw

    DEFF Research Database (Denmark)

    Pedersen, Mads; Johansen, Katja S.; Meyer, Anne S.

    2011-01-01

    Background: The recent development of improved enzymes and pentose-using yeast for cellulosic ethanol processes calls for new attention to the lignocellulose pretreatment step. This study assessed the influence of pretreatment pH, temperature, and time, and their interactions on the enzymatic...... alkaline pretreatments. Alkaline pretreatments also solubilized most of the lignin. Conclusions: Pretreatment pH exerted significant effects and factor interactions on the enzymatic glucose and xylose releases. Quite extreme pH values were necessary with mild thermal pretreatment strategies (T...... glucose and xylose yields from mildly pretreated wheat straw in multivariate experimental designs of acid and alkaline pretreatments. Results: The pretreatment pH was the most significant factor affecting both the enzymatic glucose and xylose yields after mild thermal pretreatments at maximum 140 degrees...

  1. Possible involvement of ROS generation in vorinostat pretreatment induced enhancement of the antibacterial activity of ciprofloxacin

    Directory of Open Access Journals (Sweden)

    Masadeh MM

    2017-10-01

    Full Text Available Majed M Masadeh,1 Karem H Alzoubi,2 Sayer I Al-azzam,2 Ahlam M Al-buhairan3 1Department of Pharmaceutical Technology, 2Department of Clinical Pharmacy, Jordan University of Science and Technology, Irbid, Jordan; 3Department of Clinical Laboratory Sciences, King Saud University, Riyadh, Saudi Arabia Abstract: The mechanism underlying ciprofloxacin action involves interference with transcription and replication of bacterial DNA and, thus, the induction of double-strand breaks in DNA. It also involves elevated oxidative stress, which might contribute to bacterial cell death. Vorinostat was shown to induce oxidative DNA damage. The current work investigated a possible interactive effect of vorinostat on ciprofloxacin-induced cytotoxicity against a number of reference bacteria. Standard bacterial strains were Escherichia coli ATCC 35218, Staphylococcus aureus ATCC29213, Pseudomonas aeruginosa ATCC 9027, Staphylococcus epidermidis ATCC 12228, Acinetobacter baumannii ATCC 17978, Proteus mirabilis ATCC 12459, Klebsiella pneumoniae ATCC 13883, methicillin-resistant Staphylococcus aureus (MRSA (ATCC 43300, and Streptococcus pneumoniae (ATCC 25923. The antibacterial activity of ciprofloxacin, with or without pretreatment of bacterial cells by vorinostat, was examined using the disc diffusion procedure and determination of the minimum inhibitory concentration (MIC and zones of inhibition of bacterial growth. All tested bacterial strains showed sensitivity to ciprofloxacin. When pretreated with vorinostat, significantly larger zones of inhibition and smaller MIC values were observed in all bacterial strains compared to those treated with ciprofloxacin alone. In correlation, generation of reactive oxygen species (ROS induced by the antibacterial action of ciprofloxacin was enhanced by treatment of bacterial cells with vorinostat. Results showed the possible agonistic properties of vorinostat when used together with ciprofloxacin. This could be related to the

  2. User involvement in the innovation process

    DEFF Research Database (Denmark)

    Christensen, Dan Saugstrup

    2008-01-01

    User involvement in the innovation process is not a new phenomenon. However, combined with the growing individualisation of demand and with highly competitive and dynamic environments, user involvement in the innovation process and thereby in the design, development, and manufacturing process, can...... nevertheless provide a competitive advantage. This is the case as an intensified user involvement in the innovation process potentially results in a more comprehensive understanding of the user needs and requirements and the context within which these are required, and thereby provides the possibility...... of developing better and more suitable products. The theoretical framework of this thesis is based on user involvement in the innovation process and how user involvement in the innovation process can be deployed in relation to deriving and colleting user needs and requirements, and thereby serves...

  3. Biomass Deconstruction and Pretreatment | Bioenergy | NREL

    Science.gov (United States)

    Deconstruction and Pretreatment Biomass Deconstruction and Pretreatment Our mission is to transform -cyclohexane hydrocarbons were produced by noble metal and acid zeoloite catalytic upgrading of biomass-derived by mechanical refining process. The left side shows biomass feedstock (represented by brown spheres

  4. A comparative analysis of selected wastewater pretreatment processes in food industry

    Science.gov (United States)

    Jaszczyszyn, Katarzyna; Góra, Wojciech; Dymaczewski, Zbysław; Borowiak, Robert

    2018-02-01

    The article presents a comparative analysis of the classical coagulation with the iron sulphate and adsorption on bentonite for the pretreatment of wastewater in the food industry. As a result of the studies, chemical oxygen demand (COD) and total nitrogen (TN) reduction were found to be comparable in both technologies, and a 29% higher total phosphorus removal efficiency by the coagulation was observed. After the coagulation and adsorption processes, a significant difference between mineral and organic fraction in the sludge was found (49% and 51% for bentonite and 28% and 72% for iron sulphate, respectively).

  5. Comparison of microwave and conduction-convection heating autohydrolysis pretreatment for bioethanol production.

    Science.gov (United States)

    Aguilar-Reynosa, Alejandra; Romaní, Aloia; Rodríguez-Jasso, Rosa M; Aguilar, Cristóbal N; Garrote, Gil; Ruiz, Héctor A

    2017-11-01

    This work describes the application of two forms of heating for autohydrolysis pretreatment on isothermal regimen: conduction-convection heating and microwave heating processing using corn stover as raw material for bioethanol production. Pretreatments were performed using different operational conditions: residence time (10-50 min) and temperature (160-200°C) for both pretreatments. Subsequently, the susceptibility of pretreated solids was studied using low enzyme loads, and high substrate loads. The highest conversion was 95.1% for microwave pretreated solids. Also solids pretreated by microwave heating processing showed better ethanol conversion in simultaneous saccharification and fermentation process (92% corresponding to 33.8g/L). Therefore, microwave heating processing is a promising technology in the pretreatment of lignocellulosic materials. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Flow-through pretreatment of lignocellulosic biomass with inorganic nanoporous membranes

    Energy Technology Data Exchange (ETDEWEB)

    Bhave, Ramesh R.; Lynd, Lee; Shao, Xiongjun

    2018-04-03

    A process for the pretreatment of lignocellulosic biomass is provided. The process generally includes flowing water through a pretreatment reactor containing a bed of particulate ligno-cellulosic biomass to produce a pressurized, high-temperature hydrolyzate exit stream, separating solubilized compounds from the hydrolyzate exit stream using an inorganic nanoporous membrane element, fractionating the retentate enriched in solubilized organic components and recycling the permeate to the pretreatment reactor. The pretreatment process provides solubilized organics in concentrated form for the subsequent conversion into biofuels and other chemicals.

  7. FRACTIONAL CRYSTALLIZATION TESTING WITH INTERIM PRETREATMENT SYSTEM FEEDS

    International Nuclear Information System (INIS)

    HERTING DL

    2008-01-01

    The fractional crystallization process was developed as a pretreatment method for saltcake waste retrieved from Hanford single-shell tanks (SST). The process separates the retrieved SST waste into a high-level waste stream containing the bulk of the radionuclides and a low-activity waste stream containing the bulk of the nonradioactive sodium salts. The Interim Pretreatment System project shifted the focus on pretreatment planning from SST waste to double-shell tank waste

  8. Saponification pretreatment and solids recirculation as a new anaerobic process for the treatment of slaughterhouse waste.

    Science.gov (United States)

    Affes, R; Palatsi, J; Flotats, X; Carrère, H; Steyer, J P; Battimelli, A

    2013-03-01

    Different configurations of anaerobic process, adapted to the treatment of solid slaughterhouse fatty waste, were proposed and evaluated in this study. The tested configurations are based on the combination of anaerobic digestion with/without waste saponification pretreatment (70 °C during 60 min) and with/without recirculation of the digestate solid fraction (ratio=20% w/w). After an acclimation period of substrate pulses-feeding cycles, the reactors were operated in a semi-continuous feeding mode, increasing organic loading rates along experimental time. The degradation of the raw substrate was shown to be the bottleneck of the whole process, obtaining the best performance and process yields in the reactor equipped with waste pretreatment and solids recirculation. Saponification promoted the emulsification and bioavailability of solid fatty residues, while recirculation of solids minimized the substrate/biomass wash-out and induced microbial adaptation to the treatment of fatty substrates. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Gamma radiation pretreatment in processing technology of ruminant feed: a pilot scale trial run

    International Nuclear Information System (INIS)

    Mat Rasol Awang

    2002-01-01

    The technology for production ruminant feed from agriculture by-product remains scare despite plentiful availability of feeding materials worldwide. Factors that prohibit the process technology development suggested that their peculiar physical make up, high cost of production and inferior product quality compared to established raw material, had consequently impeding the effort. In Malaysia, only two pilot plants exist; they demonstrate utilization of Oil Palm Frond (OPF) into feed. In the case of OPF in situ utilization as feed, farmers use chipper machine or shredder to process it. Other by-products have not been successfully exploited, except for Palm Kernel Cake (PKC) and Palm Oil Mill Effluent (POME) that already in commercial operation. In view of the by-product availability as feeding material in ruminant feeding system and availability of new chipper and shredder machines, the prospect of processing agriculture by-products into feed is expected to be a promising business venture. This paper describes the technology for production of new feed from oil palm Empty Fruit Bunch (EFB). It elaborates on Sterifeed Plant Operation based on plant capacity of 0.5 ton/day production. The operation aspects discuss raw materials handling and pretreatment involving γ-ray as an integral part of the total system. In this process EFB initially pasteurized and predigested by fungi in fermentation process into feed materials, and the product were fed in fresh form to animal. The operation exercise had established actual process flow, identified problems and process drawbacks. Based on this experience, availability of localized raw materials EFB at the palm oil mill and rapid development of processing machinery, it is very likely that a commercially viable feed processing plant can be established in the near future. (Author)

  10. Effect of L-Cysteine Pretreatment on the Control of Formaldehyde and Browning of the Culinary-Medicinal Shiitake Mushroom, Lentinus edodes (Higher Basidiomycetes) during Drying and Canning Processes.

    Science.gov (United States)

    Li, Guijie; Wang, Qiang; Sun, Peng; Chen, Feng; Chen, Xiaolin; Wang, Cun; Zhao, Xin

    2015-01-01

    Fresh culinary-medicinal Shiitake mushrooms (Lentinus edodes) were pretreated by soaking in 0.1 mg/mL of L-cysteine solution for 1 hour; then the variation in formaldehyde content and browning degree were studied during hot air-drying and canning processes. The results indicated that L-cysteine pretreatment significantly inhibited the increase of formaldehyde content and browning during the drying process; these increases in the pretreatment groups ranged from 7.0% to 14.0% and 65.4% to 68.9%, respectively, of that of the control groups. While the L-cysteine pretreatment did not seem to have a significant effect on controlling the formaldehyde content during the canning process, the increase of the browning degree of the canned products of the pretreatment groups ranged from 64.8% to 78.5% of that of the control groups, indicating the inhibitive effect of L-cysteine on browning during the canning process of L. edodes. Overall, L-cysteine pretreatment improved the sensory quality of both dried and canned L. edodes.

  11. Alkaline-mechanical pretreatment process for enhanced anaerobic digestion of thickened waste activated sludge with a novel crushing device: Performance evaluation and economic analysis.

    Science.gov (United States)

    Cho, Si-Kyung; Ju, Hyun-Jun; Lee, Jeong-Gyu; Kim, Sang-Hyoun

    2014-08-01

    Although various pretreatments have been widely investigated to enhance the anaerobic digestion (AD) of waste activated sludge (WAS), economic feasibility issues have limited real-world applications. The authors examined the performance and economic analysis of an alkaline-mechanical process with a novel mechanical crushing device for thickened WAS pretreatment. The pretreatment at 40gTS/L, pH 13, and 90min reaction time achieved 64% of solubilization efficiency and 8.3 times higher CH4 yield than the control. In addition, a synergistic CH4 yield enhancement was observed when the pretreated and raw WAS were used together as feedstock, and the greatest synergy was observed at a volumetric mixture ratio of 50:50. Economic estimates indicate that up to 22% of WAS treatment costs would be saved by the installation of the suggested process. The experimental results clearly indicate that the alkaline-mechanical process would be highly effective and economically feasible for the AD of thickened WAS. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Changes in the Material Characteristics of Maize Straw during the Pretreatment Process of Methanation

    Directory of Open Access Journals (Sweden)

    Yongzhong Feng

    2012-01-01

    Full Text Available Pretreatment technology is important to the direct methanation of straw. This study used fresh water, four bacterium agents (stem rot agent, “result” microbe decomposition agent, straw pretreatment composite bacterium agent, and complex microorganism agent, biogas slurry, and two chemical reagents (sodium hydroxide and urea as pretreatment promoters. Different treatments were performed, and the changes in the straw pH value, temperature, total solid (TS, volatile solid (VS, and carbon-nitrogen ratio (C/N ratio under different pretreatment conditions were analyzed. The results showed that chemical promoters were more efficient than biological promoters in straw maturity. Pretreatment using sodium hydroxide induced the highest degree of straw maturity. However, its C/N ratio had to be reduced during fermentation. In contrast, the C/N ratio of the urea-pretreated straw was low and was easy to regulate when used as anaerobic digestion material. The biogas slurry pretreatment was followed by pretreatments using four different bacterium agents, among which the effect of the complex microorganism agent (BA4 was more efficient than the others. The current study is significant to the direct and efficient methanation of straw.

  13. Biogas Production from Citrus Wastes and Chicken Feather: Pretreatment and Codigestion

    Energy Technology Data Exchange (ETDEWEB)

    Forgacs, Gergely

    2012-07-01

    Anaerobic digestion is a sustainable and economically feasible waste management technology, which lowers the emission of greenhouse gases (GHGs), decreases the soil and water pollution, and reduces the dependence on fossil fuels. The present thesis investigates the anaerobic digestion of waste from food-processing industries, including citrus wastes (CWs) from juice processing and chicken feather from poultry slaughterhouses. Juice processing industries generate 15-25 million tons of citrus wastes every year. Utilization of CWs is not yet resolved, since drying or incineration processes are costly, due to the high moisture content; and biological processes are hindered by its peel oil content, primarily the D-limonene. Anaerobic digestion of untreated CWs consequently results in process failure because of the inhibiting effect of the produced and accumulated VFAs. The current thesis involves the development of a steam explosion pretreatment step. The methane yield increased by 426 % to 0.537 Nm{sup 3}/kg VS by employing the steam explosion treatment at 150 deg C for 20 min, which opened up the compact structure of the CWs and removed 94 % of the D-limonene. The developed process enables a production of 104 m{sup 3} methane and 8.4 L limonene from one ton of fresh CWs. Poultry slaughterhouses generate a significant amount of feather every year. Feathers are basically composed of keratin, an extremely strong and resistible structural protein. Methane yield from feather is low, around 0.18 Nm{sup 3}/kg VS, which corresponds to only one third of the theoretical yield. In the present study, chemical, enzymatic and biological pretreatment methods were investigated to improve the biogas yield of feather waste. Chemical pretreatment with Ca(OH){sub 2} under relatively mild conditions (0.1 g Ca(OH){sub 2}/g TS{sub feather}, 100 deg C, 30 min) improved the methane yield to 0.40 Nm{sup 3}/kg VS, corresponding to 80 % of the theoretical yield. However, prior to digestion, the

  14. Enzymatic hydrolsis of pretreated rice straw

    Energy Technology Data Exchange (ETDEWEB)

    Vlasenko, E.Y.; Shoemaker, S.P. [California Inst. of Food and Agricultural Research, Davis, CA (United States); Ding, H. [California Univ., Davis (Canada). Dept. of Food Science and Technology; Labavitch, J.M. [California Univ., Davis, CA (United States). Dept. of Pomology

    1997-02-01

    California rice straw is being evaluated as a feedstock for production of power and fuel. This paper examines the initial steps in the process: pretreatment of rice straw and enzymatic hydrolysis of the polysaccharides in the pretreated material to soluble sugars. Rice straw was subjected to three distinct pretreatment procedures: acid-catalyzed steam explosion (Swan Biomass Company), acid hydrolysis (U.S. DOE National Renewable Energy Laboratory), and ammonia fiber explosion or AFEX (Texas A and M University). Standard conditions for each pretreatment were used, but none was optimized for rice straw specifically. Six commercial cellulases, products of Genencor International (USA), Novo (Denmark), Iogen (Canada) and Fermtech (Russia) were used for hydrolysis. The Swan- and the acid-pretreatments effectively removed hemicellulose from rice straw, providing high yields of fermentable sugars. The AFEX-pretreatment was distinctly different from other pretreatments in that it did not significantly solubilize hemicellulose. All three pretreatment procedures substantially increased enzymatic digestibility of rice straw. Three commercial Trichoderma-reesei-derived enzyme preparations: Cellulase 100L (Iogen), Spezyme CP (Genencor), and Al (Fermtech), were more active on pretreated rice straw compared than others tested. Conditions for hydrolysis of rice straw using Cellulase 100L were evaluated. The supplementation of this enzyme preparation with cellobiase (Novozyme 188) significantly improved the parameters of hydrolysis for the Swan- and the acid-pretreated materials, but did not affect the hydrolysis of the AFEX-pretreated rice straw. (Author)

  15. Effects of plasma pretreatment on the process of self-forming Cu–Mn alloy barriers for Cu interconnects

    Directory of Open Access Journals (Sweden)

    Jae-Hyung Park

    2018-02-01

    Full Text Available This study investigated the effect of plasma pretreatment on the process of a self-forming Cu–Mn alloy barrier on porous low-k dielectrics. To study the effects of plasma on the performance of a self-formed Mn-based barrier, low-k dielectrics were pretreated with H2 plasma or NH3 plasma. Cu–Mn alloy materials on low-k substrates that were subject to pretreatment with H2 plasma exhibited lower electrical resistivity values and the formation of thicker Mn-based interlayers than those on low-k substrates that were subject to pretreatment with NH3 plasma. Transmission electron microscopy (TEM, X-ray photoemission spectroscopy (XPS, and thermal stability analyses demonstrated the exceptional performance of the Mn-based interlayer on plasma-pretreated low-k substrates with regard to thickness, chemical composition, and reliability. Plasma treating with H2 gas formed hydrophilic Si–OH bonds on the surface of the low-k layer, resulting in Mn-based interlayers with greater thickness after annealing. However, additional moisture uptake was induced on the surface of the low-k dielectric, degrading electrical reliability. By contrast, plasma treating with NH3 gas was less effective with regard to forming a Mn-based interlayer, but produced a Si–N/C–N layer on the low-k surface, yielding improved barrier characteristics.

  16. Biorefining of wheat straw: accounting for the distribution of mineral elements in pretreated biomass by an extended pretreatment-severity equation.

    Science.gov (United States)

    Le, Duy Michael; Sørensen, Hanne R; Knudsen, Niels Ole; Schjoerring, Jan K; Meyer, Anne S

    2014-01-01

    Mineral elements present in lignocellulosic biomass feedstocks may accumulate in biorefinery process streams and cause technological problems, or alternatively can be reaped for value addition. A better understanding of the distribution of minerals in biomass in response to pretreatment factors is therefore important in relation to development of new biorefinery processes. The objective of the present study was to examine the levels of mineral elements in pretreated wheat straw in response to systematic variations in the hydrothermal pretreatment parameters (pH, temperature, and treatment time), and to assess whether it is possible to model mineral levels in the pretreated fiber fraction. Principal component analysis of the wheat straw biomass constituents, including mineral elements, showed that the recovered levels of wheat straw constituents after different hydrothermal pretreatments could be divided into two groups: 1) Phosphorus, magnesium, potassium, manganese, zinc, and calcium correlated with xylose and arabinose (that is, hemicellulose), and levels of these constituents present in the fiber fraction after pretreatment varied depending on the pretreatment-severity; and 2) Silicon, iron, copper, aluminum correlated with lignin and cellulose levels, but the levels of these constituents showed no severity-dependent trends. For the first group, an expanded pretreatment-severity equation, containing a specific factor for each constituent, accounting for variability due to pretreatment pH, was developed. Using this equation, the mineral levels could be predicted with R(2) > 0.75; for some with R(2) up to 0.96. Pretreatment conditions, especially pH, significantly influenced the levels of phosphorus, magnesium, potassium, manganese, zinc, and calcium in the resulting fiber fractions. A new expanded pretreatment-severity equation is proposed to model and predict mineral composition in pretreated wheat straw biomass.

  17. Drying characteristics of osmotically pretreated cranberries : Energy and quality aspects

    Energy Technology Data Exchange (ETDEWEB)

    Grabowski, S.; Marcotte, M. [Agriculture and Agri-Food Canada, St. Hyacinthe, PQ (Canada). Food Research and Development Centre; Poirier, M.; Kudra, T. [Natural Resources Canada, Varennes, PQ (Canada). CANMET Energy Technology Centre

    2002-06-01

    This paper presents the results of a study in which osmotically pretreated cranberries were dried. The osmotic treatment included dehydration and sugar infusion. The process involved pretreating halved cranberries in a standard osmotic solution followed by freeze-drying, vacuum-drying and air-drying in various dryers, such as cabinet-air-through, fluid bed, pulsed fluid bed, and vibrated fluid bed dryers. The intent was to identify the best drying technology. The comparison criteria selected were energy consumption and product quality. Product quality for freeze-dried berries was quantified based on anthocyanins content, rehydration ratio, color, and taste. Unit heat consumption could be used for selecting the drying method, as all other drying methods yielded similar but slightly lower quality products. The highest energy efficiency was obtained with the vibrated fluid bed and the pulsed fluid bed. It was noted that drying rates were reduced during the second drying period when sugar was infused into the cranberries during osmotic pretreatment, but the total energy consumption was reduced by osmotic dehydration. 22 refs., 1 tab., 5 figs.

  18. Improving anaerobic digestion of sugarcane straw for methane production: Combined benefits of mechanical and sodium hydroxide pretreatment for process designing

    International Nuclear Information System (INIS)

    Janke, Leandro; Weinrich, Sören; Leite, Athaydes F.; Terzariol, Filippi K.; Nikolausz, Marcell; Nelles, Michael; Stinner, Walter

    2017-01-01

    Highlights: • NaOH pretreatment was tested to improve degradation of SCS for methane production. • Low NaOH concentration accelerated AD of SCS but not increased the methane yield. • Mild and high NaOH concentrations accelerated and increased methane yield of SCS. • NaOH use increased OPEX but provided a higher profitability than the untreated SCS. • Anaerobic reactor price showed a high influence on sensitivity analysis. - Abstract: Sodium hydroxide (NaOH) as an alkaline pretreatment method to enhance the degradation kinetics of sugarcane straw (SCS) for methane production was investigated with a special focus on the benefits for designing the anaerobic digestion process. For that, SCS was previously homogenized by milling in 2 mm particle size and pretreated in NaOH solutions at various concentrations (0, 3, 6 and 12 g NaOH/100 g SCS) and the methane yields were determined in biochemical methane potential (BMP) tests. The obtained experimental data were used to simulate a large-scale semi-continuous process (100 ton SCS day"−"1) according to a first-order reaction model and the main economic indicators were calculated based on cash flows of each pretreatment condition. The BMP tests showed that by increasing the NaOH concentration the conversion of the fibrous fraction of the substrate to methane was not only accelerated (higher α value), but also increased by 11.9% (from 260 to 291 mL CH_4 gVS"−"1). By using the experimental data to simulate the large-scale process these benefits were translated to a reduction of up to 58% in the size of the anaerobic reactor (and consequently in electricity consumption for stirring), while the methane yield increased up to 28%, if the liquid fraction derived from the pretreatment process is also used for methane production. Although the use of NaOH for substrate pretreatment has considerably increased the operational expenditures (from 0.97 up to 1.97 € × 10"6 year"−"1), the pretreatment method was able to

  19. Technospheric Mining of Rare Earth Elements from Bauxite Residue (Red Mud): Process Optimization, Kinetic Investigation, and Microwave Pretreatment.

    Science.gov (United States)

    Reid, Sable; Tam, Jason; Yang, Mingfan; Azimi, Gisele

    2017-11-10

    Some rare earth elements (REEs) are classified under critical materials, i.e., essential in use and subject to supply risk, due to their increasing demand, monopolistic supply, and environmentally unsustainable and expensive mining practices. To tackle the REE supply challenge, new initiatives have been started focusing on their extraction from alternative secondary resources. This study puts the emphasis on technospheric mining of REEs from bauxite residue (red mud) produced by the aluminum industry. Characterization results showed the bauxite residue sample contains about 0.03 wt% REEs. Systematic leaching experiments showed that concentrated HNO 3 is the most effective lixiviant. However, because of the process complexities, H 2 SO 4 was selected as the lixiviant. To further enhance the leaching efficiency, a novel process based on microwave pretreatment was employed. Results indicated that microwave pretreatment creates cracks and pores in the particles, enabling the lixiviant to diffuse further into the particles, bringing more REEs into solution, yielding of 64.2% and 78.7% for Sc and Nd, respectively, which are higher than the maximum obtained when HNO 3 was used. This novel process of "H 2 SO 4 leaching-coupled with-microwave pretreatment" proves to be a promising technique that can help realize the technological potential of REE recovery from secondary resources, particularly bauxite residue.

  20. Performance and enhanced mechanism of a novel bio-diatomite biofilm pretreatment process treating polluted raw water.

    Science.gov (United States)

    Yang, Guang-feng; Feng, Li-juan; Wang, Sha-fei; Yang, Qi; Xu, Xiang-yang; Zhu, Liang

    2015-09-01

    A lab-scale novel bio-diatomite biofilm process (BDBP) was established for the polluted raw water pretreatment in this study. Results showed that a shorter startup period of BDBP system was achieved under the completely circulated operation mode, and the removal efficiencies of nitrogen and disinfection by-product precursor were effective at low hydraulic retention time of 2-4 h due to high biomass attached to the carrier and diatomite. A maximum NH4(+)-N oxidation potential predicted by modified Stover-Kincannon model was 333.3 mg L(-1) d(-1) in the BDBP system, which was 4.7 times of that in the control reactor. Results demonstrated that the present of bio-diatomite favors the accumulation of functional microbes in the oligotrophic niche, and the pollutants removal performance of this novel process was enhanced for polluted raw water pretreatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Understanding of alkaline pretreatment parameters for corn stover enzymatic saccharification

    Directory of Open Access Journals (Sweden)

    Chen Ye

    2013-01-01

    Full Text Available Abstract Background Previous research on alkaline pretreatment has mainly focused on optimization of the process parameters to improve substrate digestibility. To achieve satisfactory sugar yield, extremely high chemical loading and enzyme dosages were typically used. Relatively little attention has been paid to reduction of chemical consumption and process waste management, which has proven to be an indispensable component of the bio-refineries. To indicate alkali strength, both alkali concentration in pretreatment solution (g alkali/g pretreatment liquor or g alkali/L pretreatment liquor and alkali loading based on biomass solids (g alkali/g dry biomass have been widely used. The dual approaches make it difficult to compare the chemical consumption in different process scenarios while evaluating the cost effectiveness of this pretreatment technology. The current work addresses these issues through pretreatment of corn stover at various combinations of pretreatment conditions. Enzymatic hydrolysis with different enzyme blends was subsequently performed to identify the effects of pretreatment parameters on substrate digestibility as well as process operational and capital costs. Results The results showed that sodium hydroxide loading is the most dominant variable for enzymatic digestibility. To reach 70% glucan conversion while avoiding extensive degradation of hemicellulose, approximately 0.08 g NaOH/g corn stover was required. It was also concluded that alkali loading based on total solids (g NaOH/g dry biomass governs the pretreatment efficiency. Supplementing cellulase with accessory enzymes such as α-arabinofuranosidase and β-xylosidase significantly improved the conversion of the hemicellulose by 6–17%. Conclusions The current work presents the impact of alkaline pretreatment parameters on the enzymatic hydrolysis of corn stover as well as the process operational and capital investment costs. The high chemical consumption for alkaline

  2. Foaming and Antifoaming and Gas Entrainment in Radioactive Waste Pretreatment and Immobilization Processes. Final Report

    International Nuclear Information System (INIS)

    Wasan, Darsh T.

    2007-01-01

    The Savannah River Site (SRS) and Hanford site are in the process of stabilizing millions of gallons of radioactive waste slurries remaining from production of nuclear materials for the Department of Energy (DOE). The Defense Waste Processing Facility (DWPF) at SRS is currently vitrifying the waste in borosilicate glass, while the facilities at the Hanford site are in the construction phase. Both processes utilize slurry-fed joule-heated melters to vitrify the waste slurries. The DWPF has experienced difficulty during operations. The cause of the operational problems has been attributed to foaming, gas entrainment and the rheological properties of the process slurries. The rheological properties of the waste slurries limit the total solids content that can be processed by the remote equipment during the pretreatment and meter feed processes. Highly viscous material can lead to air entrainment during agitation and difficulties with pump operations. Excessive foaming in waste evaporators can cause carryover of radionuclides and non-radioactive waste to the condensate system. Experimental and theoretical investigations of the surface phenomena, suspension rheology and bubble generation of interactions that lead to foaming and air entrainment problems in the DOE High Level and Low Activity Radioactive Waste separation and immobilization processes were pursued under this project. The first major task accomplished in the grant proposal involved development of a theoretical model of the phenomenon of foaming in a three-phase gas-liquid-solid slurry system. This work was presented in a recently completed Ph.D. thesis (9). The second major task involved the investigation of the inter-particle interaction and microstructure formation in a model slurry by the batch sedimentation method. Both experiments and modeling studies were carried out. The results were presented in a recently completed Ph.D. thesis. The third task involved the use of laser confocal microscopy to study

  3. Making lignin accessible for anaerobic digestion by wet-explosion pretreatment

    DEFF Research Database (Denmark)

    Ahring, Birgitte Kiær; Biswas, Rajib; Ahamed, Aftab

    2015-01-01

    of lignin during anaerobic digestion processes. The pretreatment of feedlot manure was performed in a 10 L reactor at 170 C for 25 min using 4 bars oxygen and the material was fed to a continuous stirred tank reactor operated at 55 C for anaerobic digestion. Methane yield of untreated and pretreated...... material was 70 ± 27 and 320 ± 36 L/kg-VS/day, respectively, or 4.5 times higher yield as a result of the pretreatment. Aliphatic acids formed during the pretreatment were utilized by microbes. 44.4% lignin in pretreated material was actually converted in the anaerobic digestion process compared to 12...

  4. Hazard Analysis for the Pretreatment Engineering Platform (PEP)

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Robin S.; Geeting, John GH; Lawrence, Wesley E.; Young, Jonathan

    2008-07-10

    The Pretreatment Engineering Platform (PEP) is designed to perform a demonstration on an engineering scale to confirm the Hanford Waste Treatment Plant Pretreatment Facility (PTF) leaching and filtration process equipment design and sludge treatment process. The system will use scaled prototypic equipment to demonstrate sludge water wash, caustic leaching, oxidative leaching, and filtration. Unit operations to be tested include pumping, solids washing, chemical reagent addition and blending, heating, cooling, leaching, filtration, and filter cleaning. In addition, the PEP will evaluate potential design changes to the ultrafiltration process system equipment to potentially enhance leaching and filtration performance as well as overall pretreatment throughput. The skid-mounted system will be installed and operated in the Processing Development Laboratory-West at Pacific Northwest National Laboratory (PNNL) in Richland, Washington.

  5. An overview of key pretreatment processes for biological conversion of lignocellulosic biomass to bioethanol

    OpenAIRE

    Maurya, Devendra Prasad; Singla, Ankit; Negi, Sangeeta

    2015-01-01

    Second-generation bioethanol can be produced from various lignocellulosic biomasses such as wood, agricultural or forest residues. Lignocellulosic biomass is inexpensive, renewable and abundant source for bioethanol production. The conversion of lignocellulosic biomass to bioethanol could be a promising technology though the process has several challenges and limitations such as biomass transport and handling, and efficient pretreatment methods for total delignification of lignocellulosics. P...

  6. EFFECT OF AQUEOUS PRETREATMENT ON PYROLYSIS CHARACTERISTICS OF NAPIER GRASS

    Directory of Open Access Journals (Sweden)

    ISAH YAKUB MOHAMMED

    2015-11-01

    Full Text Available Effect of non-catalytic aqueous pretretment on pyrolysis characteristics of Napier grass was investigated using thermogravimetric analyser. Increasing pretreatment severity (0.0-2.0 improved pyrolysis process. The residual mass at the end of pyrolysis for the pretreated sample was about 50% less compared to the untreated sample. Kinetics of the process was evaluated using order based model and both pretreated and untreated samples followed first order reaction. The activation energy of the pretreated samples was similar and higher than that of the raw sample which was attributed to faster rate of decomposition due removal of hetromaterials (ash, extractives and some hemicellulose in the pretreatment stage. Finally, this pretreatment method has demonstrated effectiveness for the removal of pyrolysis retardants and will improve the quantity and quality of bio-oil yield.

  7. Biorefining of wheat straw: accounting for the distribution of mineral elements in pretreated biomass by an extended pretreatment – severity equation

    DEFF Research Database (Denmark)

    Le, Duy Michael; Sørensen, Hanne Risbjerg; Knudsen, Niels Ole

    2014-01-01

    Background: Mineral elements present in lignocellulosic biomass feedstocks may accumulate in biorefinery process streams and cause technological problems, or alternatively can be reaped for value addition. A better understanding of the distribution of minerals in biomass in response to pretreatment...... factors is therefore important in relation to development of new biorefinery processes. The objective of the present study was to examine the levels of mineral elements in pretreated wheat straw in response to systematic variations in the hydrothermal pretreatment parameters (pH, temperature......) Silicon, iron, copper, aluminum correlated with lignin and cellulose levels, but the levels of these constituents showed no severity-dependent trends. For the first group, an expanded pretreatment-severity equation, containing a specific factor for each constituent, accounting for variability due...

  8. Pretreatment of Real Wastewater from the Chocolate Manufacturing Industry through an Integrated Process of Electrocoagulation and Sand Filtration

    Directory of Open Access Journals (Sweden)

    Marco A. García-Morales

    2018-01-01

    Full Text Available The purpose of this study was to evaluate the efficiency of removal of suspended solids in terms of turbidity, color, and chemical oxygen demand (COD when integrating the electrocoagulation process using aluminum sacrificial anodes and the sand filtration process as a pretreatment of wastewater from the chocolate manufacturing plant in Toluca, México. Wastewater from the chocolate manufacturing industry used in this study is classified as nontoxic, but is characterized as having a high content of color (5952 ± 76 Pt-Co, turbidity (1648 ± 49 FAU, and COD (3608 ± 250 mg/L. Therefore, enhanced performance could be achieved by combining pretreatment techniques to increase the efficiencies of the physical, chemical, and biological treatments. In the integrated process, there was a turbidity reduction of 96.1 ± 0.2% and an increase in dissolved oxygen from 3.8 ± 0.05 mg/L (inlet sand filtration to 6.05 ± 0.03 mg/L (outlet sand filtration after 120 min of treatment. These results indicate good water quality necessary for all forms of elemental life. Color and COD removals were 98.2 ± 0.2% and 39.02 ± 2.2%, respectively, during the electrocoagulation process (0.2915 mA/cm2 current density and 120 min of treatment. The proposed integrated process could be an attractive alternative of pretreatment of real wastewater to increase water quality of conventional treatments.

  9. Innovative pretreatment strategies for biogas production.

    Science.gov (United States)

    Patinvoh, Regina J; Osadolor, Osagie A; Chandolias, Konstantinos; Sárvári Horváth, Ilona; Taherzadeh, Mohammad J

    2017-01-01

    Biogas or biomethane is traditionally produced via anaerobic digestion, or recently by thermochemical or a combination of thermochemical and biological processes via syngas (CO and H 2 ) fermentation. However, many of the feedstocks have recalcitrant structure and are difficult to digest (e.g., lignocelluloses or keratins), or they have toxic compounds (such as fruit flavors or high ammonia content), or not digestible at all (e.g., plastics). To overcome these challenges, innovative strategies for enhanced and economically favorable biogas production were proposed in this review. The strategies considered are commonly known physical pretreatment, rapid decompression, autohydrolysis, acid- or alkali pretreatments, solvents (e.g. for lignin or cellulose) pretreatments or leaching, supercritical, oxidative or biological pretreatments, as well as combined gasification and fermentation, integrated biogas production and pretreatment, innovative biogas digester design, co-digestion, and bio-augmentation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Pretreatment status report on the identification and evaluation of alternative processes. Milestone Report No. C064

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, D.G. [Westinghouse Hanford Co., Richland, WA (United States); Brothers, A.J. [Pacific Northwest Lab., Richland, WA (United States); Beary, M.M.; Nicholson, G.A. [Science Applications International Corp., San Diego, CA (United States)

    1993-09-01

    The purpose of this report is to support the development and demonstration of a pretreatment system that will (1) destroy organic materials and ferrocyanide in tank wastes so that the wastes can be stored safely, (2) separate the high-activity and low-activity fractions, (3) remove radionuclides and remove or destroy hazardous chemicals in LLW as necessary to meet waste form feed requirements, (4) support development and demonstration of vitrification technology by providing representative feeds to the bench-scale glass melter, (5) support full-scale HLW vitrification operations, including near-term operation, by providing feed that meets specifications, and (6) design and develop pretreatment processes that accomplish the above objectives and ensure compliance with environmental regulations. This report is a presentation of candidate technologies for pretreatment of Hanford Site tank waste. Included are descriptions of studies by the Pacific Northwest Laboratory of Battelle Memorial Institute; Science Applications International Corporation, an independent consultant; BNFL, Inc. representing British technologies; Numatec, representing French technologies; and brief accounts of other relevant activities.

  11. Survey of Lignin-Structure Changes and Depolymerization during Ionic Liquid Pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, Tanmoy; Isern, Nancy G.; Sun, Jian; Wang, Eileen; Hull, Sarah; Cort, John R.; Simmons, Blake A.; Singh, Seema

    2017-09-26

    A detailed study of chemical changes in lignin structure during the ionic liquid (IL) pretreatment process is not only pivotal for understanding and overcoming biomass recalcitrance during IL pretreatment, but also is necessary for designing new routes for lignin valorization. Chemical changes in lignin were systematically studied as a function of pretreatment temperature, time and type of IL used. Kraft lignin was used as the lignin source and common pretreatment conditions were employed using three different ILs of varying chemical structure in terms of acidic or basic character. The chemical changes in the lignin structure due to IL pretreatment processes were monitored using 1H-13C HSQC NMR, 31P NMR, elemental analysis, GPC, FT-IR, and the depolymerized products were analyzed using GC-MS. Although pretreatment in acidic IL, triethylammonium hydrogensulfate ([TEA][HSO4]) results in maximum decrease in β-aryl ether bond, maximum dehydration and recondensation pathways were also evident, with the net process showing a minimum decrease in the molecular weight of regenerated lignin. However, 1-ethyl-3-methylimidazolium acetate ([C2C1Im][OAc]) pretreatment yields a smaller decrease in the β-aryl ether content along with minimum evidence of recondensation, resulting in the maximum decrease in the molecular weight. Cholinium lysinate ([Ch][Lys]) pretreatment shows an intermediate result, with moderate depolymerization, dehydration and recondensation observed. The depolymerization products after IL pretreatment are found to be a function of the pretreatment temperature and the specific chemical nature of the IL used. At higher pretreatment temperature, [Ch][Lys] pretreatment yields guaiacol, [TEA][HSO4] yields guaiacylacetone, and [C2C1Im][OAc] yields both guaiacol and guaiacylacetone as major products. These results clearly indicate that the changes in lignin structure as well as the depolymerized product profile depend on the pretreatment conditions and the nature

  12. Separation processes for the pretreatment of high-level nuclear wastes at the Savannah River site - 59291

    International Nuclear Information System (INIS)

    Hobbs, David; Peters, Thomas; Taylor-Pashow, Kathryn; Fondeur, Fernando; Nash, Charles; Fink, Samuel; Herman, David; Marra, Jim

    2012-01-01

    Document available in abstract form only. Full text of publication follows: Separation methods for the pretreatment of the high-level nuclear wastes (HLW) at the Savannah River Site (SRS) include the Caustic Side Solvent Extraction (CSSX) process for cesium and adsorption/ion exchange for the removal of cesium, strontium and alpha-emitting actinides. The CSSX process uses a calixarene extractant in combination with phase modifiers in a hydrocarbon diluent. Monosodium titanate (MST), a hydrous metal oxide, is the baseline material for the removal of strontium and alpha-emitting radionuclides (principally Pu-238, Pu-239, Pu-240 and Np-237). Two pretreatment facilities, the Modular Caustic Side Solvent Extraction Unit (MCU) and the Actinide Removal Process (ARP) facility began radioactive operations at SRS in 2008. Together these facilities can treat approximately 4 million liters of waste per year. The same separation processes are also planned for the much larger Salt Waste Processing Facility (SWPF). The SWPF, which has a design throughput of about 27 million liters per year, is under construction and scheduled to begin radioactive operations in 2014. Current R and D activities for the CSSX process are focused on implementing a new solvent system and stripping flowsheet that offers enhanced extraction and stripping of cesium. This next generation solvent system features a different calixarene extractant, uses caustic instead of nitric acid

  13. Kinetics of leather dyeing pretreated with enzymes: role of acid protease.

    Science.gov (United States)

    Kanth, Swarna Vinodh; Venba, Rajangam; Jayakumar, Gladstone Christopher; Chandrababu, Narasimhan Kannan

    2009-04-01

    In the present investigation, kinetics of dyeing involving pretreatment with acid protease has been presented. Application of acid protease in dyeing process resulted in increased absorption and diffusion of dye into the leather matrix. Enzyme treatment at 1% concentration, 60 min duration and 50 degrees C resulted in maximum of 98% dye exhaustion and increased absorption rate constants. The final exhaustion (C(infinity)) for the best fit of CI Acid Black 194 dye has been 98.5% with K and r2 values from the modified Cegarra-Puente isotherm as 0.1033 and 0.0631. CI Acid Black 194 being a 2:1 metal complex acid dye exhibited higher absorption rate than the acid dye CI Acid Black 210. A reduction in 50% activation energy calculated from Arrhenius equation has been observed in enzyme assisted dyeing process of both the dyes that substantiates enhanced dye absorption. The absorption rate constant calculated with modified Cegarra-Puente equation confirm higher rate constants and faster kinetics for enzyme assisted dyeing process. Enzyme treated leather exhibited richness of color and shade when compared with control. The present study substantiates the essential role of enzyme pretreatment as an eco-friendly leather dyeing process.

  14. Effects of coconut granular activated carbon pretreatment on membrane filtration in a gravitational driven process to improve drinking water quality.

    Science.gov (United States)

    da Silva, Flávia Vieira; Yamaguchi, Natália Ueda; Lovato, Gilselaine Afonso; da Silva, Fernando Alves; Reis, Miria Hespanhol Miranda; de Amorim, Maria Teresa Pessoa Sousa; Tavares, Célia Regina Granhen; Bergamasco, Rosângela

    2012-01-01

    This study evaluates the performance of a polymeric microfiltration membrane, as well as its combination with a coconut granular activated carbon (GAC) pretreatment, in a gravitational filtration module, to improve the quality of water destined to human consumption. The proposed membrane and adsorbent were thoroughly characterized using instrumental techniques, such as contact angle, Brunauer-Emmett-Teller) and Fourier transform infrared spectroscopy analyses. The applied processes (membrane and GAC + membrane) were evaluated regarding permeate flux, fouling percentage, pH and removal of Escherichia coli, colour, turbidity and free chlorine. The obtained results for filtrations with and without GAC pretreatment were similar in terms of water quality. GAC pretreatment ensured higher chlorine removals, as well as higher initial permeate fluxes. This system, applying GAC as a pretreatment and a gravitational driven membrane filtration, could be considered as an alternative point-of-use treatment for water destined for human consumption.

  15. Pre-treatment step with Leuconostoc mesenteroides or L. pseudomesenteroides strains removes furfural from Zymomonas mobilis ethanolic fermentation broth.

    Science.gov (United States)

    Hunter, William J; Manter, Daniel K

    2014-10-01

    Furfural is an inhibitor of growth and ethanol production by Zymomonas mobilis. This study used a naturally occurring (not GMO) biological pre-treatment to reduce that amount of furfural in a model fermentation broth. Pre-treatment involved inoculating and incubating the fermentation broth with strains of Leuconostoc mesenteroides or Leuconostoc pseudomesenteroides. The Leuconostoc strains converted furfural to furfuryl alcohol without consuming large amounts of dextrose in the process. Coupling this pre-treatment to ethanolic fermentation reduced furfural in the broth and improved growth, dextrose uptake and ethanol formation. Pre-treatment permitted ethanol formation in the presence of 5.2 g L(-1) furfural, which was otherwise inhibitive. The pre-treatment and presence of the Leuconostoc strains in the fermentation broth did not interfere with Z. mobilis ethanolic fermentation or the amounts of ethanol produced. The method suggests a possible technique for reducing the effect that furfural has on the production of ethanol for use as a biofuel. Published by Elsevier Ltd.

  16. Integrated Process for Ethanol, Biogas, and Edible Filamentous Fungi-Based Animal Feed Production from Dilute Phosphoric Acid-Pretreated Wheat Straw.

    Science.gov (United States)

    Nair, Ramkumar B; Kabir, Maryam M; Lennartsson, Patrik R; Taherzadeh, Mohammad J; Horváth, Ilona Sárvári

    2018-01-01

    Integration of wheat straw for a biorefinery-based energy generation process by producing ethanol and biogas together with the production of high-protein fungal biomass (suitable for feed application) was the main focus of the present study. An edible ascomycete fungal strain Neurospora intermedia was used for the ethanol fermentation and subsequent biomass production from dilute phosphoric acid (0.7 to 1.2% w/v) pretreated wheat straw. At optimum pretreatment conditions, an ethanol yield of 84 to 90% of the theoretical maximum, based on glucan content of substrate straw, was observed from fungal fermentation post the enzymatic hydrolysis process. The biogas production from the pretreated straw slurry showed an improved methane yield potential up to 162% increase, as compared to that of the untreated straw. Additional biogas production, using the syrup, a waste stream obtained post the ethanol fermentation, resulted in a combined total energy output of 15.8 MJ/kg wheat straw. Moreover, using thin stillage (a waste stream from the first-generation wheat-based ethanol process) as a co-substrate to the biogas process resulted in an additional increase by about 14 to 27% in the total energy output as compared to using only wheat straw-based substrates. ᅟ.

  17. Alternatives generation and analysis for the phase 1 high-level waste pretreatment process selection

    International Nuclear Information System (INIS)

    Manuel, A.F.

    1997-01-01

    This report evaluates the effects of enhanced sludge washing and sludge washing without caustic leaching during the preparation of the Phase 1 high-level waste feeds. The pretreatment processing alternatives are evaluated against their ability to satisfy contractual, cost minimization, and other criteria. The information contained in this report is consistent with, and supplemental to, the Tank Waste Remediation System Operation and Utilization Plan (Kirkbride et al. 1997)

  18. Alternatives generation and analysis for the phase 1 high-level waste pretreatment process selection

    Energy Technology Data Exchange (ETDEWEB)

    Manuel, A.F.

    1997-10-02

    This report evaluates the effects of enhanced sludge washing and sludge washing without caustic leaching during the preparation of the Phase 1 high-level waste feeds. The pretreatment processing alternatives are evaluated against their ability to satisfy contractual, cost minimization, and other criteria. The information contained in this report is consistent with, and supplemental to, the Tank Waste Remediation System Operation and Utilization Plan (Kirkbride et al. 1997).

  19. Bioethanol from lignocellulose - pretreatment, enzyme immobilization and hydrolysis kinetics

    DEFF Research Database (Denmark)

    Tsai, Chien Tai

    , the cost of enzyme is still the bottle neck, re-using the enzyme is apossible way to reduce the input of enzyme in the process. In the point view of engineering, the prediction of enzymatic hydrolysis kinetics under different substrate loading, enzyme combination is usful for process design. Therefore...... lignocellulose is the required high cellulase enzyme dosages that increase the processing costs. One method to decrease the enzyme dosage is to re-use BG, which hydrolyze the soluble substrate cellobiose. Based on the hypothesis that immobilized BG can be re-used, how many times the enzyme could be recycled...... liquid and pretreatment time can be reduced, the influence of substrate concentration, pretreatment time and temperature were investigated and optimized. Pretreatment of barley straw by [EMIM]Ac, correlative models were constructed using 3 different pretreatment parameters (temperature, time...

  20. Previously unclassified bacteria dominate during thermophilic and mesophilic anaerobic pre-treatment of primary sludge.

    Science.gov (United States)

    Pervin, Hasina M; Batstone, Damien J; Bond, Philip L

    2013-06-01

    Thermophilic biological pre-treatment enables enhanced anaerobic digestion for treatment of wastewater sludges but, at present, there is limited understanding of the hydrolytic-acidogenic microbial composition and its contribution to this process. In this study, the process was assessed by comparing the microbiology of thermophilic (50-65 °C) and mesophilic (35 °C) pre-treatment reactors treating primary sludge. A full-cycle approach for the 16S rRNA genes was applied in order to monitor the diversity of bacteria and their abundance in a thermophilic pre-treatment reactor treating primary sludge. For the thermophilic pre-treatment (TP), over 90% of the sequences were previously undetected and these had less than 97% sequence similarity to cultured organisms. During the first 83 days, members of the Betaproteobacteria dominated the community sequences and a newly designed probe was used to monitor a previously unknown bacterium affiliated with the genus Brachymonas. Between days 85 and 183, three phylotypes that affiliated with the genera Comamonas, Clostridium and Lysobacter were persistently dominant in the TP community, as revealed by terminal-restriction fragment length polymorphism (T-RFLP). Hydrolytic and fermentative functions have been speculated for these bacteria. Mesophilic pre-treatment (MP) and TP communities were different but they were both relatively dynamic. Statistical correlation analysis and the function of closely allied reference organisms indicated that previously unclassified bacteria dominated the TP community and may have been functionally involved in the enhanced hydrolytic performance of thermophilic anaerobic pre-treatment. This study is the first to reveal the diversity and dynamics of bacteria during anaerobic digestion of primary sludge. Copyright © 2013 Elsevier GmbH. All rights reserved.

  1. Bioethanol production: Pretreatment and enzymatic hydrolysis of softwood

    Energy Technology Data Exchange (ETDEWEB)

    Tengborg, Charlotte

    2000-05-01

    The enzymatic hydrolysis process can be used to produce bioethanol from softwood, which are the dominating raw material in the Northern hemisphere. This thesis deals with the development of the process focusing on the pretreatment and the enzymatic hydrolysis stages. The influence of pretreatment conditions on sugar yield, and the effect of inhibitors on the ethanol yield, were investigated for spruce and pine. The maximum yields of hemicellulose sugars and glucose were obtained under different pretreatment conditions. This indicates that two-stage pretreatment may be preferable. The added catalysts, H{sub 2}SO{sub 4} and SO{sub 2}, resulted in similar total sugar yields about 40 g/100 g dry raw material. However, the fermentability of SO{sub 2}-impregnated material was better. This pretreatment resulted in the formation of inhibitors to the subsequent process steps, e.g. sugar and lignin degradation products. The glucose yield in the enzymatic hydrolysis stage was affected by various parameters such as enzyme loading, temperature, pH, residence time, substrate concentration, and agitation. To decrease the amount of fresh water used and thereby waste water produced, the sugar-rich prehydrolysate from the pretreatment step was included in the enzymatic hydrolysis of the solid fraction, resulting in a reduction in the cellulose conversion of up to 36%. Different prehydrolysate detoxification methods, such as treatment with Ca(OH){sub 2}, laccase, and fermentation using yeast, were investigated. The latter was shown to be very efficient. The amount of fresh water used can be further reduced by recycling various process streams. This was simulated experimentally in a bench-scale process. A reduction in fresh water demand of 50% was obtained without any further negative effects on either hydrolysis or fermentation.

  2. Improved microbial conversion of de-oiled Jatropha waste into biohydrogen via inoculum pretreatment: process optimization by experimental design approach

    Directory of Open Access Journals (Sweden)

    Gopalakrishnan Kumar

    2015-03-01

    Full Text Available In this study various pretreatment methods of sewage sludge inoculum and the statistical process optimization of de-oiled jatropha waste have been reported. Peak hydrogen production rate (HPR and hydrogen yield (HY of 0.36 L H2/L-d and 20 mL H2/g Volatile Solid (VS were obtained when heat shock pretreatment (95 oC, 30 min was employed. Afterwards, an experimental design was applied to find the optimal conditions for H2 production using heat-pretreated seed culture. The optimal substrate concentration, pH and temperature were determined by using response surface methodology as 205 g/L, 6.53 and 55.1 oC, respectively. Under these circumstances, the highest HPR of 1.36 L H2/L-d was predicted. Verification tests proved the reliability of the statistical approach. As a result of the heat pretreatment and fermentation optimization, a significant (~ 4 folds increase in HPR was achieved. PCR-DGGE results revealed that Clostridium sp. were majorly present under the optimal conditions.

  3. Characterization of lignin during oxidative and hydrothermal pre-treatment processes of wheat straw and corn stover.

    Science.gov (United States)

    Kaparaju, Prasad; Felby, Claus

    2010-05-01

    The objective of the study was to characterize and map changes in lignin during hydrothermal and wet explosion pre-treatments of wheat straw and corn stover. Chemical composition, microscopic (atomic force microscopy and scanning electron microscopy) and spectroscopic (attenuated total reflectance Fourier transform infrared spectroscopy, ATR-FTIR) analyses were performed. Results showed that both pre-treatments improved the cellulose and lignin content with substantial removal of hemicellulose in the pre-treated biomasses. These values were slightly higher for hydrothermal compared to wet explosion pre-treatment. ATR-FTIR analyses also confirmed these results. Microscopic analysis showed that pre-treatments affected the biomass by partial difibration. Lignin deposition on the surface of the hydrothermally pre-treated fibre was very distinct while severe loss of fibril integrity was noticed with wet exploded fibre. The present study thus revealed that the lignin cannot be removed by the studied pre-treatments. However, both pre-treatments improved the accessibility of the biomass towards enzymatic hydrolysis. Copyright 2009 Elsevier Ltd. All rights reserved.

  4. Potable water recovery for spacecraft application by electrolytic pretreatment/air evaporation

    Science.gov (United States)

    Wells, G. W.

    1975-01-01

    A process for the recovery of potable water from urine using electrolytic pretreatment followed by distillation in a closed-cycle air evaporator has been developed and tested. Both the electrolytic pretreatment unit and the air evaporation unit are six-person, flight-concept prototype, automated units. Significantly extended wick lifetimes have been achieved in the air evaporation unit using electrolytically pretreated, as opposed to chemically pretreated, urine feed. Parametric test data are presented on product water quality, wick life, process power, maintenance requirements, and expendable requirements.

  5. Phenotypic selection of a wild Saccharomyces cerevisiae strain for simultaneous saccharification and co-fermentation of AFEX pretreated corn stover

    Science.gov (United States)

    Mingie Jin; Cory Sarks; Christa Gunawan; Benjamin D. Bice; Shane P. Simonett; Ragothaman Avanasi Narasimhan; Laura B. Willis; Bruce E. Dale; Venkatesh Balan; Trey K. Sato

    2013-01-01

    Simultaneous saccharification and co-fermentation (SSCF) process involves enzymatic hydrolysis of pretreated lignocellulosic biomass and fermentation of glucose and xylose in one bioreactor. The optimal temperatures for enzymatic hydrolysis are higher than the standard fermentation temperature of ethanologenic Saccharomyces cerevisiae. Moreover,...

  6. Mechanical pre-treatment for enzymatically enhanced energy efficient TMP; Mekanisk foerbehandling av flis foer effektiv enzymatisk paaverkan vid energieffektiv TMP tillverkning

    Energy Technology Data Exchange (ETDEWEB)

    Viforr, Silvia

    2008-11-15

    Thermomechanical pulp (TMP) processes are high energy demanding. This together with the high energy prices of nowadays results in significant costs, why less energy demanding processes are wished. This project has evaluated the potential for energy reductions in a TMP process by a mechanical pre-treatment of the wood chips combined with an enzymatic modification based on a cellulase mixture. The structure of the wood was opened up by the mechanical pre-treatment making it easier for the enzymes to penetrate into the pre-treated wood material. The enzymatic treatment was then run at optimum standard conditions. The EU project - Ecotarget 2004-2008 (www.ecotarget.com) have studied different types of enzymes that could be used for pre-treatment of wood chips in order to save energy during TMP processes. Based on these studies cellulose enzyme was recommended to be used at pre-treatment experiment performed by the Vaermeforsk project. Due to the fact that the Ecotarget-project has also been run during 2008 with activities involving enzymes, the steering board of the Vaermeforsk project took the decision to co-ordinate the experiments from both of the projects. This co-operation increased the funds and also the number of experiments for both of the projects. The experimental results from this project showed that energy reductions at a given tensile index could be achieved if gently mechanical pre-treated wood chips were enzymatically treated. An intensive mechanical pre-treatment gave negative effects on both fibre length and tear index while the light scattering coefficient was promoted, probably due to the fibre shortening. Enzymatic modification of mechanically pre-treated chips showed a favourable modification of the fibres, even regarding the fibre shortening, if compared to mechanical pre-treated chips only. The effects of cellulases was however not as expected, why a high amount of cellulases was used. Other types of enzymes which could attack the primary wall of

  7. Green coconut mesocarp pretreated by an alkaline process as raw material for bioethanol production.

    Science.gov (United States)

    Soares, Jimmy; Demeke, Mekonnen M; Foulquié-Moreno, Maria R; Van de Velde, Miet; Verplaetse, Alex; Fernandes, Antonio Alberto Ribeiro; Thevelein, Johan M; Fernandes, Patricia Machado Bueno

    2016-09-01

    Cocos nucifera L., coconut, is a palm of high importance in the food industry, but a considerable part of the biomass is inedible. In this study, the pretreatment and saccharification parameters NaOH solution, pretreatment duration and enzyme load were evaluated for the production of hydrolysates from green coconut mesocarp using 18% (w/v) total solids (TS). Hydrolysates were not detoxified in order to preserve sugars solubilized during the pretreatment. Reduction of enzyme load from 15 to 7.5 filter paper cellulase unit (FPU)/g of biomass has little effect on the final ethanol titer. With optimized pretreatment and saccharification, hydrolysates with more than 7% (w/v) sugars were produced in 48h. Fermentation of the hydrolysate using industrial Saccharomyces cerevisiae strains produced 3.73% (v/v) ethanol. Our results showed a simple pretreatment condition with a high-solid load of biomass followed by saccharification and fermentation of undetoxified coconut mesocarp hydrolysates to produce ethanol with high titer. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Life cycle assessment of cellulose nanofibrils production by mechanical treatment and two different pretreatment processes.

    Science.gov (United States)

    Arvidsson, Rickard; Nguyen, Duong; Svanström, Magdalena

    2015-06-02

    Nanocellulose is a bionanomaterial with many promising applications, but high energy use in production has been described as a potential obstacle for future use. In fact, life cycle assessment studies have indicated high life cycle energy use for nanocellulose. In this study, we assess the cradle-to-gate environmental impacts of three production routes for a particular type of nanocellulose called cellulose nanofibrils (CNF) made from wood pulp. The three production routes are (1) the enzymatic production route, which includes an enzymatic pretreatment, (2) the carboxymethylation route, which includes a carboxymethylation pretreatment, and (3) one route without pretreatment, here called the no pretreatment route. The results show that CNF produced via the carboxymethylation route clearly has the highest environmental impacts due to large use of solvents made from crude oil. The enzymatic and no pretreatment routes both have lower environmental impacts, of similar magnitude. A sensitivity analysis showed that the no pretreatment route was sensitive to the electricity mix, and the carboxymethylation route to solvent recovery. When comparing the results to those of other carbon nanomaterials, it was shown that in particular CNF produced via the enzymatic and no pretreatment routes had comparatively low environmental impacts.

  9. An Efficient Process for Pretreatment of Lignocelluloses in Functional Ionic Liquids

    Directory of Open Access Journals (Sweden)

    Shi-Jia Dong

    2015-01-01

    Full Text Available Background and Aims. The complex structure of the lignocelluloses is the main obstacle in the conversion of lignocellulosic biomass into valuable products. Ionic liquids provide the opportunities for their efficient pretreatment for biomass. Therefore, in this work, pretreatment of corn stalk was carried out in ultrasonic-assisted ionic liquid including 1-butyl-3-methylimidazolium chloride [BMIM]Cl, 1-H-3-methylimidazolium chloride [HMIM]Cl, and 1-(1-propylsulfonic-3-imidazolium chloride [HSO3-pMIM]Cl at 70°C for 2 h. We compared the pretreatments by ionic liquid with and without the addition of deionized water. Fourier transform infrared spectroscopy (FTIR and scanning electron microscopy (SEM were employed to analyze the chemical characteristics of regenerated cellulose-rich materials. Results. [HMIM]Cl and [HSO3-pMIM]Cl were effective in lignin extraction to obtain cellulose-rich materials. FTIR analysis and SEM analysis indicated the effective lignin removal and the reduced crystallinity of cellulose-rich materials. Enzymatic hydrolysis of cellulose-rich materials was performed efficiently. High yields of reducing sugar and glucose were obtained when the corn stalk was pretreated by [HMIM]Cl and [HSO3-pMIM]Cl. Conclusions. Ionic liquids provided the ideal environment for lignin extraction and enzymatic hydrolysis of corn stalk and [HMIM]Cl and [HSO3-pMIM]Cl proved the most efficient ionic liquids. This simple and environmentally acceptable method has a great potential for the preparation of bioethanol for industrial production.

  10. The effect of pretreatment on the performance of membrane separation processes in the circulation water systems of paper production; Esikaesittelyiden vaikutus kalvoerotusprosessien toimintaan paperinvalmistuksen vesikierroissa - EKT 01

    Energy Technology Data Exchange (ETDEWEB)

    Nuortila-Jokinen, J.; Nystroem, M. [Lappeenranta Univ. of Technology (Finland). Dept. of Chemical Technology

    1998-12-31

    The aim of this project is to establish an optimized membrane filtration process for internal water treatment in the pulp and paper industry. In membrane filtration fouling reduces the capacity of a plant, and frequent or ineffective membrane washing reduces the membrane lifetime. These factors affect directly the feasibility of the process. Moreover, the retentates have to be economically destroyed. In this project effective pretreatment systems for membrane filtration processes will be developed. The pretreatments studied will be chemical, biological (thermophilic aerobic or anaerobic processes), oxidative (ozonation or other AOP methods) or enzymatic methods or their combinations. The target is to increase capacity and/or reduce fouling in the membrane process. In addition, the effect of the different pretreatment methods on the washability of the membranes will be studied and an optimized washing routine will be developed. The composition of the forming retentates are also affected by the pretreatment used and additionally the same methods can be used for developing a sensible and economically feasible retentate posttreatment method, which will also be developed in the project. (orig.)

  11. The effect of pretreatment on the performance of membrane separation processes in the circulation water systems of paper production; Esikaesittelyiden vaikutus kalvoerotusprosessien toimintaan paperinvalmistuksen vesikierroissa - EKT 01

    Energy Technology Data Exchange (ETDEWEB)

    Nuortila-Jokinen, J; Nystroem, M [Lappeenranta Univ. of Technology (Finland). Dept. of Chemical Technology

    1999-12-31

    The aim of this project is to establish an optimized membrane filtration process for internal water treatment in the pulp and paper industry. In membrane filtration fouling reduces the capacity of a plant, and frequent or ineffective membrane washing reduces the membrane lifetime. These factors affect directly the feasibility of the process. Moreover, the retentates have to be economically destroyed. In this project effective pretreatment systems for membrane filtration processes will be developed. The pretreatments studied will be chemical, biological (thermophilic aerobic or anaerobic processes), oxidative (ozonation or other AOP methods) or enzymatic methods or their combinations. The target is to increase capacity and/or reduce fouling in the membrane process. In addition, the effect of the different pretreatment methods on the washability of the membranes will be studied and an optimized washing routine will be developed. The composition of the forming retentates are also affected by the pretreatment used and additionally the same methods can be used for developing a sensible and economically feasible retentate posttreatment method, which will also be developed in the project. (orig.)

  12. Utilization of microwave and ultrasound pretreatments in the production of bioethanol from corn

    Energy Technology Data Exchange (ETDEWEB)

    Nikolic, Svetlana; Mojovic, Ljiljana; Rakin, Marica [University of Belgrade, Faculty of Technology and Metallurgy, Belgrade (Serbia); Pejin, Dusanka; Pejin, Jelena [University of Novi Sad, Faculty of Technology, Novi Sad (Serbia)

    2011-08-15

    Bioethanol production by simultaneous saccharification and fermentation (SSF) of corn meal by Saccharomyces cerevisiae var. ellipsoideus yeast in a batch system with prior ultrasound or microwave treatment was studied. The optimal duration of the pretreatments and the SSF process kinetics were assessed and determined. Also, the effect of ultrasound and microwave pretreatments on ethanol yield and productivity was investigated. An optimal duration of 5 min was determined for both pretreatments. Ultrasonic and microwave pretreatments effectively increased the glucose concentration obtained after liquefaction by 6.82 and 8.48%, respectively, compared to untreated control sample. Also, both pretreatments improved ethanol yield and productivity during the SSF process. Ultrasound and microwave pretreatments increased the maximum ethanol concentration produced in the SSF process by 11.15 and 13.40% (compared to the control sample), respectively. The application of microwave pretreatment resulted in higher glucose release during liquefaction and consequently in higher ethanol concentration, compared to ultrasound pretreatment. A maximum ethanol concentration of 9.91% (w/w) and percentage of theoretical ethanol yield of 92.27% were achieved after 44 h of the SSF process of corn meal with prior microwave treatment. (orig.)

  13. Biologically Pre-Treated Habitation Waste Water as a Sustainable Green Urine Pre-Treat Solution

    Science.gov (United States)

    Jackson, W. Andrew; Thompson, Bret; Sevanthi, Ritesh; Morse, Audra; Meyer, Caitlin; Callahan, Michael

    2017-01-01

    The ability to recover water from urine and flush water is a critical process to allow long term sustainable human habitation in space or bases on the moon or mars. Organic N present as urea or similar compounds can hydrolyze producing free ammonia. This reaction results in an increase in the pH converting ammonium to ammonia which is volatile and not removed by distillation. The increase in pH will also cause precipitation reactions to occur. In order to prevent this, urine on ISS is combined with a pretreat solution. While use of a pretreatment solution has been successful, there are numerous draw backs including: storage and use of highly hazardous solutions, limitations on water recovery (less than 85%), and production of brine with pore dewatering characteristics. We evaluated the use of biologically treated habitation wastewaters (ISS and early planetary base) to replace the current pretreat solution. We evaluated both amended and un-amended bioreactor effluent. For the amended effluent, we evaluated "green" pretreat chemicals including citric acid and citric acid amended with benzoic acid. We used a mock urine/air separator modeled after the urine collection assembly on ISS. The urine/air separator was challenged continually for >6 months. Depending on the test point, the separator was challenged daily with donated urine and flushed with amended or un-amended reactor effluent. We monitored the pH of the urine, flush solution and residual pH in the urine/air separator after each urine event. We also evaluated solids production and biological growth. Our results support the use of both un-amended and amended bioreactor effluent to maintain the operability of the urine /air separator. The ability to use bioreactor effluent could decrease consumable cost, reduce hazards associated with current pre-treat chemicals, allow other membrane based desalination processes to be utilized, and improve brine characteristics.

  14. Pretreatment of Biomass by Aqueous Ammonia for Bioethanol Production

    Science.gov (United States)

    Kim, Tae Hyun; Gupta, Rajesh; Lee, Y. Y.

    The methods of pretreatment of lignocellulosic biomass using aqueous ammonia are described. The main effect of ammonia treatment of biomass is delignification without significantly affecting the carbohydrate contents. It is a very effective pretreatment method especially for substrates that have low lignin contents such as agricultural residues and herbaceous feedstock. The ammonia-based pretreatment is well suited for simultaneous saccharification and co-fermentation (SSCF) because the treated biomass retains cellulose as well as hemicellulose. It has been demonstrated that overall ethanol yield above 75% of the theoretical maximum on the basis of total carbohydrate is achievable from corn stover pretreated with aqueous ammonia by way of SSCF. There are two different types of pretreatment methods based on aqueous ammonia: (1) high severity, low contact time process (ammonia recycle percolation; ARP), (2) low severity, high treatment time process (soaking in aqueous ammonia; SAA). Both of these methods are described and discussed for their features and effectiveness.

  15. Tailoring Wet Explosion Process Parameters for the Pretreatment of Cocksfoot Grass for High Sugar Yields

    DEFF Research Database (Denmark)

    Njoku, Stephen Ikechukwu; Ahring, Birgitte Kiær; Uellendahl, Hinrich

    2013-01-01

    The pretreatment of lignocellulosic biomass is crucial for efficient subsequent enzymatic hydrolysis and ethanol fermentation. In this study, wet explosion (WEx) pretreatment was applied to cocksfoot grass and pretreatment conditions were tailored for maximizing the sugar yields using response...... glucose release with low formation of by-products. Under these conditions, the cellulose and hemicellulose sugar recovery was 94 % and 70 %, respectively. The efficiency of the enzymatic hydrolysis of cellulose under these conditions was 91 %. On the other hand, the release of pentose sugars was higher...... when applying less severe pretreatment conditions C (160 °C, 5 min, 0.2 % dilute sulfuric acid). Therefore, the choice of the most suitable pretreatment conditions is depending on the main target product, i.e., hexose or pentose sugars....

  16. Processing Adipose-Rich Mohs Samples: A Comparative Study of Effectiveness of Pretreatment With Liquid Nitrogen Versus Flash Freezing Spray.

    Science.gov (United States)

    Reserva, Jeave; Kozel, Zachary; Krol, Cindy; Speiser, Jodi; Adams, William; Tung, Rebecca

    2017-11-01

    Processing of adipose-rich Mohs micrographic surgery (MMS) specimens poses challenges that may preclude complete margin evaluation. In this setting, the value of additional freezing methods using various cooling agents has not been previously investigated. The aim of this study is to compare the frozen section quality of high-adipose Mohs specimens processed without additional cooling treatments versus those pretreated with 1,1,1,2-tetrafluoroethane (TFE) or liquid nitrogen (LN2). A set of 3 sections were each taken from 24 adipose-rich Mohs micrographic surgery specimens. A section from each set was subjected to either no additional cooling treatment (control), two 10-second pulse sprays of 1,1,1,2-tetrafluoroethane, or three 2-second pulse sprays of LN2. After staining, 2 blinded raters evaluated slide quality based on the presence or absence of the following features: margin completeness, nuclear clearing, epidermal or adipose folding, holes, or venetian blind-like artifacts. Pretreatment of the sample with LN2 produced a significantly (P < 0.001) greater number of high-quality slides (19/24) compared to pretreatment with 1,1,1,2-tetrafluoroethane (1/24) and no additional treatment (0/24). The adjunctive use of LN2 spray before tissue embedding circumvents the challenges of processing "thick" (high-adipose) specimens and facilitates the production of high-quality frozen section slides during Mohs micrographic surgery.

  17. Structural Changes of Lignin from Wheat Straw by Steam Explosion and Ethanol Pretreatments

    Directory of Open Access Journals (Sweden)

    Cheng Pan

    2016-06-01

    Full Text Available Effects of the pretreatment of wheat straw by steam explosion and ethanol were evaluated relative to the structural changes of lignin from the pretreated pulp. The lignin from steam explosion pulp (LS, lignin from steam blasting residual liquid (LL, lignin from ethanol pretreatment pulp (LE, lignin from black liquor (LB, and lignin from wheat straw (LW were separated, and the structural characteristics of the lignin fractions were compared based on analyses of Fourier transform-infrared, ultraviolet, thermogravimetric, and 1H and 13C nuclear magnetic resonance spectra. The proportions of the three structural units in all lignin fractions clearly changed during the pretreatment process because of inter-conversion reactions. The conjugated structure of lignin was destroyed in the pretreatment process and was also affected by the alkali extraction process. The alcoholic hydroxyl links on the aliphatic side chain were partly transformed into carbonyl groups during ethanol pretreatment. Demethoxylation occurred in all lignin fractions during the ethanol pretreatment and steam explosion process. The thermal stability of the LB fraction was relatively high because of the condensation reaction.

  18. Comparison of Pretreatment Methods on Vetiver Leaves for Efficient Processes of Simultaneous Saccharification and Fermentation by Neurospora sp.

    Science.gov (United States)

    Restiawaty, E.; Dewi, A.

    2017-07-01

    Lignocellulosic biomass is a potential raw material for bioethanol production. Neurospora sp. can be used to convert lignocellulosic biomass into bioethanol because of its ability to perform simultaneous saccharification and fermentation. However, lignin content, degree of polymerization, and crystallinity of cellulose contained in lignocellulosic biomass can inhibit cellulosic-biomass digestion by Neurospora sp, so that a suitable pretreatment method of lignocellulosic biomass is needed. The focus of this research was to investigate the suitable pretreatment method for vetiver leaves (Vetiveria zizanioides L. Nash) used as a raw material producing bioethanol in the process of simultaneous saccharification and fermentation (SSF) by Neurospora sp.. Vetiver plants obtained from Garut are deliberately cultivated to produce essential oils extracted from the roots of this plant. Since the vetiver leaves do not contain oil, some of harvested leaves are usually used for crafts and cattle feed, and the rest are burned. This study intended to look at other potential of vetiver leaves as a source of renewable energy. Pretreatments of the vetiver leaves were conducted using hot water, dilute acid, alkaline & dilute acid, and alkaline peroxide, in which each method was accompanied by thermal treatment. The results showed that the alkaline peroxide treatment is a suitable for vetiver leaves as indicated by the increase of cellulose content up to 65.1%, while the contents of hot water soluble, hemicellulose, lignin, and ash are 8.7%, 18.3%, 6.8%, and 1.1%, respectively. Using this pretreatment method, the vetiver leaves can be converted into bioethanol by SSF process using Neurospora sp. with a concentration of bioethanol of 6.7 g/L operated at room temperature.

  19. Size effects on acid bisulfite pretreatment efficiency: multiple product yields in spent liquor and enzymatic digestibility of pretreated solids

    Science.gov (United States)

    Yalan Liu; Jinwu Wang; Michael P. Wolcott

    2017-01-01

    Currently, feedstock size effects on chemical pretreatment performance were not clear due to the complexity of the pretreatment process and multiple evaluation standards such as the sugar recovery in spent liquor or enzymatic digestibility. In this study, we evaluated the size effects by various ways: the sugar recovery and coproduct yields in spent liquor, the...

  20. Dry ice blasting as a substitution for the conventional electroplating pre-treatments

    Directory of Open Access Journals (Sweden)

    Uhlmann Eckart

    2016-01-01

    Full Text Available For high quality electroplated products, surfaces must be thoroughly pre-treated. For this purpose electroplating currently needs a variety of chemical baths. The used chemicals are injurious to health and harmful to the environment. In addition, the conventional pre-treatment has a long process time which results in high costs. Dry ice blasting alone or in combination with other processes has the potential to completely substitute these conventional pre-treatment processes. Three process sequences as pre-treatment methods prior to electroplating were investigated on the aluminium alloys AlSi12 and AlMg3. The used processes are dry ice blasting, tempering during dry ice blasting and glass bead blasting followed by dry ice blasting. The influence of the parameters on the surface roughness, surface topography and surface tension of the workpieces was examined. A model to describe the correlation between the dry ice blasting parameters and surface parameters was developed. Finally, an adhesion test of electroplated specimen was conducted in order to determine the suitability of these alternative pre-treatment processes.

  1. Motivational Influences on Cognition: Task Involvement, Ego Involvement, and Depth of Information Processing.

    Science.gov (United States)

    Graham, Sandra; Golan, Shari

    1991-01-01

    Task involvement and ego involvement were studied in relation to depth of information processing for 126 fifth and sixth graders in 2 experiments. Ego involvement resulted in poorer word recall at deep rather than shallow information processing levels. Implications for the study of motivation are discussed. (SLD)

  2. Hydrolysis of alkaline pretreated banana peel

    Science.gov (United States)

    Fatmawati, A.; Gunawan, K. Y.; Hadiwijaya, F. A.

    2017-11-01

    Banana peel is one of food wastes that are rich in carbohydrate. This shows its potential as fermentation substrate including bio-ethanol. This paper presented banana peel alkaline pretreatment and enzymatic hydrolysis. The pretreatment was intended to prepare banana peel in order to increase hydrolysis performance. The alkaline pretreatment used 10, 20, and 30% w/v NaOH solution and was done at 60, 70 and 80°C for 1 hour. The hydrolysis reaction was conducted using two commercial cellulose enzymes. The reaction time was varied for 3, 5, and 7 days. The best condition for pretreatment process was one conducted using 30% NaOH solution and at 80°C. This condition resulted in cellulose content of 90.27% and acid insoluble lignin content of 2.88%. Seven-day hydrolysis time had exhibited the highest reducing sugar concentration, which was7.2869 g/L.

  3. Carbohydrate degradation mechanisms and compounds from pretreated biomass

    DEFF Research Database (Denmark)

    Rasmussen, Helena

    The formation of inhibitors during pretreatment of lignocellulosic feedstocks is a persistent problem, and notably the compounds that retard enzymatic cellulose conversion represent an obstacle for achieving optimal enzymatic productivity and high glucose yields. Compounds with many chemical...... pretreated wheat straw after enzymatic treatment. It was found that formation of the oligophenolic degradation compounds were common across biomass sources as sugar cane bagasse and oil palm empty fruit bunches. These findings were in line with that the oligophenolic compounds arise from reactions involving...... functionalities are formed during biomass pretreatment, which gives possibilities for various chemical reactions to take place and hence formation of many new potential inhibitor compounds. This somehow overlooked contemplation formed the basis for the main hypothesis investigated in this work: Hypothesis 1...

  4. Description of project for pretreatment and storage of wastes of L.P.R. (Radiochemical Processes Laboratory)

    International Nuclear Information System (INIS)

    Doval, J.C.F.; Mehlich, A.M.; Quilici, D.F.

    1987-01-01

    The aim of the project is to allow the start up and operation of LPR (Radiochemical Processes Laboratory) as part of the intended activities in the plant. In this paper, the pretreatment and storage of liquid wastes generated at the LPR are described. The pretreatment section will be set up inside the shielded cells already existent in the LPR, where a previous concentration through the evaporation of liquid wastes will take place. The storage section has to be constructed on purpose in order to temporarily store the concentrates. The cells of transference and preconditioning of solid wastes are also described. These cells will be mounted inside the building, allowing the handling of radioactive solids generated as effluents during the reprocessing plan. In the description, the use of non conventional materials for the boiler making and the construction of cells is specially mentioned. (Author)

  5. Uncertainty and approximate reasoning in waste pretreatment planning

    International Nuclear Information System (INIS)

    Agnew, S.F.; Eisenhawer, S.W.; Bott, T.F.

    1998-01-01

    Waste pretreatment process planning within the DOE complex must consider many different outcomes in order to perform the tradeoffs necessary to accomplish this important national mission. One of the difficulties encountered by many who assess these tradeoffs is that the complexity of this problem taxes the abilities of any single person or small group of individuals. For example, uncertainties in waste composition as well as process efficiency are well known yet incompletely considered in the search for optimum solutions. This paper describes a tool, the pre-treatment Process Analysis Tool (PAT), for evaluating tank waste pretreatment options at Hanford, Oak Ridge, Idaho National Environmental and Engineering Laboratory, and Savannah River Sites. The PAT propagates uncertainty in both tank waste composition and process partitioning into a set of ten outcomes. These outcomes are, for example, total cost, Cs-137 in iLAW, iHLW MT, and so on. Tradeoffs among outcomes are evaluated or scored by means of an approximate reasoning module that uses linguistic bases to evaluate tradeoffs for each process based on user valuations of outcomes

  6. Pretreatment process for mineral analysis in FFH using INAA-method and evaluation of mineral intakes

    International Nuclear Information System (INIS)

    Lee, Ok Hee; Youn, Kyung Jin; Lee, Ji Bum; Kim, Mi Jin

    2010-05-01

    This study were aimed to set up the pre-treatment process for FFH and analyse Pretreatment processes for the analysis of food mineral contents by INAA were established according to FFH state using freeze-drying and homogenization. The Se contents showed higher precision with INAA-method than ICP-method. The content of Ca, Na, Mg, Fe, Zn, Cu, Mn, Cr, Co in FFH measured using INAA-method showed that the mineral contents in the amount of recommended intakes by manufacturer were not significantly different according to FFH type. The average Ca contents was the highest in Yousanguns > nutritional supplement> glucosamines. The average K content of FFH with one serving size were the highest in glucosamines>aloes> nutritional supplements. I content among FFH was the highest in nutritional supplements. The average Mg contents were highest in Chlorella-Spirurina and Aloes. The average Cu content of FFH was the highest in Yeasts. The contents of Fe, Zn and Se were the highest in nutritional supplements. The mineral contents in recommended intake amounts by manufacturer were over the maximum contents regulated by Korean FDA in some imported FFH products. their mineral contents of FFH using NAA-method and to assess the mineral intakes by FFH

  7. Pretreatment process for mineral analysis in FFH using INAA-method and evaluation of mineral intakes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ok Hee; Youn, Kyung Jin; Lee, Ji Bum; Kim, Mi Jin [Yongin University, Yongin (Korea, Republic of)

    2010-05-15

    This study were aimed to set up the pre-treatment process for FFH and analyse Pretreatment processes for the analysis of food mineral contents by INAA were established according to FFH state using freeze-drying and homogenization. The Se contents showed higher precision with INAA-method than ICP-method. The content of Ca, Na, Mg, Fe, Zn, Cu, Mn, Cr, Co in FFH measured using INAA-method showed that the mineral contents in the amount of recommended intakes by manufacturer were not significantly different according to FFH type. The average Ca contents was the highest in Yousanguns > nutritional supplement> glucosamines. The average K content of FFH with one serving size were the highest in glucosamines>aloes> nutritional supplements. I content among FFH was the highest in nutritional supplements. The average Mg contents were highest in Chlorella-Spirurina and Aloes. The average Cu content of FFH was the highest in Yeasts. The contents of Fe, Zn and Se were the highest in nutritional supplements. The mineral contents in recommended intake amounts by manufacturer were over the maximum contents regulated by Korean FDA in some imported FFH products. their mineral contents of FFH using NAA-method and to assess the mineral intakes by FFH

  8. Biomass pretreatment

    Science.gov (United States)

    Hennessey, Susan Marie; Friend, Julie; Elander, Richard T; Tucker, III, Melvin P

    2013-05-21

    A method is provided for producing an improved pretreated biomass product for use in saccharification followed by fermentation to produce a target chemical that includes removal of saccharification and or fermentation inhibitors from the pretreated biomass product. Specifically, the pretreated biomass product derived from using the present method has fewer inhibitors of saccharification and/or fermentation without a loss in sugar content.

  9. Process Testing Results and Scaling for the Hanford Waste Treatment and Immobilization Plant (WTP) Pretreatment Engineering Platform - 10173

    International Nuclear Information System (INIS)

    Kurath, Dean E.; Daniel, Richard C.; Baldwin, David L.; Rapko, Brian M.; Barnes, Steven M.; Gilbert, Robert A.; Mahoney, Lenna A.; Huckaby, James L.

    2010-01-01

    The U.S. Department of Energy-Office of River Protections Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being designed and built to pretreat and then vitrify a large portion of the wastes in Hanfords 177 underground waste storage tanks at Richland, Washington. In support of this effort, engineering-scale tests at the Pretreatment Engineering Platform (PEP) have been completed to confirm the process design and provide improved projections of system capacity. The PEP is a 1/4.5-scale facility designed, constructed, and operated to test the integrated leaching and ultrafiltration processes being deployed at the WTP. The PEP replicates the WTP leaching processes with prototypic equipment and control strategies and non-prototypic ancillary equipment to support the core processing. The testing approach used a nonradioactive aqueous slurry simulant to demonstrate the unit operations of caustic and oxidative leaching, cross-flow ultrafiltration solids concentration, and solids washing. Parallel tests conducted at the laboratory scale with identical simulants provided results that allow scale-up factors to be developed between the laboratory and PEP performance. This paper presents the scale-up factors determined between the laboratory and engineering-scale results and presents arguments that extend these results to the full-scale process.

  10. Optimization of pretreatment, process performance, mass and energy balance in the anaerobic digestion of Arachis hypogaea (Peanut) hull

    International Nuclear Information System (INIS)

    Dahunsi, S.O.; Oranusi, S.; Efeovbokhan, V.E.

    2017-01-01

    Highlights: • Biogas was maximally produced from the anaerobic digestion of peanut hull. • Thermo-alkaline pretreatment enhanced enormous biogas yield from the biomass. • The optimal condition for maximal biogas yield were established. • The digestate has great potentials for usage as biofertilizers/soil conditioner. • The pretreatment is economical by converting the gas to heat and electric energies. - Abstract: The potential of a major bioresource (Peanut hull) for biogas generation was evaluated. A sample was pretreated using combinations of mechanical and thermo-alkaline procedures using the Central Composite Design (CCD) for the optimization of the pretreatment temperature and time while another sample was treated without thermo-alkaline methods. The physico-chemical and microbial characteristics of the A. hypogaea hull and the rumen contents were carried out using standard methods. The actual biogas yields were 1739.20 m"3/kg TSfed and 1100.50 m"3/kg TSfed with desirability values of 91 and 100% for the pretreated and untreated experiments respectively. The methane and carbon dioxide content of biogas from both experiments as revealed by Gas chromatography were 61.5 ± 2.5%; 24 ± 1% and 51 ± 2%; 25 ± 2% respectively. The optimization of important process parameters in the anaerobic digestion were done using CCD of Response Surface Methodology (RSM) and the Artificial Neural Networks (ANNs) and the optimal values for each of the five major parameters optimized are as follows: Temperature = 30.00 °C, pH = 7.50, Retention time = 30.00 day, Total solids = 12.00 g/kg and Volatile solids = 4.00 g/kg. Taking these values into account, the predicted biogas yield for RSM was 1819.89 m"3/kg TSfed and 1743.6 m"3/kg TSfed for ANNs in the thermo-alkaline pretreated experiment. For the experiment without pretreatment, the RSM predicted yield was 1119.54 m"3/kg TSfed while that of ANNs was 1103.40 m"3/kg TSfed. In all there was a 38.5% increase in predicted

  11. Enhancement of biogas production in anaerobic co-digestion by ultrasonic pretreatment

    International Nuclear Information System (INIS)

    Zou, Shuzhen; Wang, Xiaojiao; Chen, Yuanlin; Wan, Haiwen; Feng, Yongzhong

    2016-01-01

    Highlights: • Ultrasonic pretreatment changed physical structure of samples. • Ultrasonic pretreatment improved biogas production via changing environment before and during anaerobic digestion process. • The main factors affecting biogas production differ in different pretreated samples. - Abstract: This paper optimized the anaerobic digestion (AD) pretreatment process and identified the influence of pretreatment on the co-digestion of maize straw (MS) and dairy manure (DM). In the study, ultrasonic was used to pretreat MS and DM prior to digestion, with power intensities of 0, 189.39, 284.09, and 378.79 kJ at 0, 20, 30, and 40 min, respectively. Changes in the surface structures of MS and DM were observed by scanning electron microscopy (SEM), and factor analysis was used to analyze the main factors affecting biogas production in the AD process. The result showed that the structure of DM was distributed and that the structure of MS became more roughness following the ultrasonic pretreatment (UP). The highest total biogas production of co-digestion (240.32 mL/g VS_f_e_d) was obtained when MS was pretreated for 30 min without DM pretreatment (MS_3_0DM_0). This was significantly higher than that of the untreated sample (CK) (141.65 mL/g VS_f_e_d). The cellulose activity (CA), reducing sugar (RS) content, volatile fatty acid (VFA) content and pH in the digester feed, and their maximum and minimum values in the AD process was affected by UP. Factor 1 of MS_3_0DM_0 was determined by RS content, pH and VFA content that they had the most influence on biogas production on days 6, 18, 24 and 30. Factor 2 of it was determined by CA, and it had most influence on days 0, 12, 36 and 42 in the AD process, The result of the factor analysis indicated that the main factors affecting biogas production were affected by UP and they differ according to the different digestion stages. This research concluded that UP improved total biogas production via changing the initial

  12. Microwave pretreatment of switchgrass for bioethanol production

    Science.gov (United States)

    Keshwani, Deepak Radhakrishin

    conditions, 82% glucose and 63% xylose yields were achieved for switchgrass, and 87% glucose and 59% xylose yields were achieved for coastal bermudagrass following enzymatic hydrolysis of the pretreated biomass. The optimum enzyme loadings were 15 FPU/g and 20 CBU/g for switchgrass and 10 FPU/g and 20 CBU/g for coastal bermudagrass. Dielectric properties for dilute sodium hydroxide solutions were measured and compared to solid loss, lignin reduction and reducing sugar levels in hydrolyzates. Results indicate that the dielectric loss tangent of alkali solutions is a potential indicator of the severity of microwave-based pretreatments. Modeling of pretreatment processes can be a valuable tool in process simulations of bioethanol production from lignocellulosic biomass. Chapter 4 discusses three different approaches that were used to model delignification and carbohydrate loss during microwave-based pretreatment of switchgrass: statistical linear regression modeling, kinetic modeling using a time-dependent rate coefficient, and a Mamdani-type fuzzy inference system. The dielectric loss tangent of the alkali reagent and pretreatment time were used as predictors in all models. The statistical linear regression model for delignification gave comparable root mean square error (RMSE) values for training and testing data and predictions were approximately within 1% of experimental values. The kinetic model for delignification and xylan loss gave comparable RMSE values for training and testing data sets and predictions were approximately within 2% of experimental values. The kinetic model for cellulose loss was not as effective and predictions were only within 5-7% of experimental values. The time-dependent rate coefficients of the kinetic models calculated from experimental data were consistent with the heterogeneity (or lack thereof) of individual biomass components. The Mamdani-type fuzzy inference system was shown to be an effective means to model pretreatment processes and gave

  13. Hydrothermal pretreatment of wood by mild steam explosion and hot water extraction.

    Science.gov (United States)

    Wojtasz-Mucha, Joanna; Hasani, Merima; Theliander, Hans

    2017-10-01

    The aim of this work was to compare the two most common hydrothermal pre-treatments for wood - mild steam explosion and hot water extraction - both with the prospect of enabling extraction of hemicelluloses and facilitating further processing. Although both involve autohydrolysis of the lignocellulosic tissue, they are performed under different conditions: the most prominent difference is the rapid, disintegrating, discharge employed in the steam explosion opening up the structure. In this comparative study, the emphasis was placed on local composition of the pre-treated wood chips (of industrially relevant size). The results show that short hot water extraction treatments lead to significant variations in the local composition within the wood chips, while steam explosion accomplishes a comparably more even removal of hemicelluloses due to the advective mass transport during the explosion step. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Investigation of the impacts of thermal pretreatment on waste activated sludge and development of a pretreatment model.

    Science.gov (United States)

    Burger, Gillian; Parker, Wayne

    2013-09-15

    This study investigated the impacts of high pressure thermal hydrolysis (HPTH) pretreatment on the distribution of chemical oxygen demand (COD) species in waste activated sludge (WAS). In the first phase of the project, WAS from a synthetically-fed biological reactor (BR) was fed to an aerobic digester (AD). In the second phase, WAS from the BR was pretreated by HPTH at 150 °C and 3 bars for 30 min prior to being fed to the AD. A range of physical, biochemical and biological properties were regularly measured in each process stream in both phases. The COD of the BR WAS consisted of storage products (XSTO), active heterotrophs (XH) and endogenous decay products (XE). Pretreatment did not increase the extent to which the BR WAS was aerobically digested and hence it was concluded that the unbiodegradable COD fraction, i.e. XE, was unchanged by pretreatment. However, pretreatment did increase the rate of degradation as it converted 36% of XH to readily biodegradable COD (SB) and the remaining XH to slowly biodegradable COD (XB). Furthermore, XSTO was fully converted to SB by pretreatment. Although pretreatment did not change the VSS concentration in the downstream aerobic digester, it did decrease the ISS concentration by 46 ± 11%. This reduced the total mass of solids produced by the digester by 21 ± 8%. A COD-based HPTH pretreatment model was developed and calibrated. When this model was integrated into BioWin 3.1(®), it was able to accurately simulate both the steady state performance of the overall system employed in this study as well as dynamic respirometry results. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Characterization of Cellulase Enzyme Inhibitors Formed During the Chemical Pretreatments of Rice Straw

    Science.gov (United States)

    Rajan, Kalavathy

    Production of fuels and chemicals from a renewable and inexpensive resource such as lignocellulosic biomass is a lucrative and sustainable option for the advanced biofuel and bio-based chemical platform. Agricultural residues constitute the bulk of potential feedstock available for cellulosic fuel production. On a global scale, rice straw is the largest source of agricultural residues and is therefore an ideal crop model for biomass deconstruction studies. Lignocellulosic biofuel production involves the processes of biomass conditioning, enzymatic saccharification, microbial fermentation and ethanol distillation, and one of the major factors affecting its techno-economic feasibility is the biomass recalcitrance to enzymatic saccharification. Preconditioning of lignocellulosic biomass, using chemical, physico-chemical, mechanical and biological pretreatments, is often practiced such that biomass becomes available to downstream processing. Pretreatments, such as dilute acid and hot water, are effective means of biomass conversion. However, despite their processing importance, preconditioning biomass also results in the production of carbohydrate and lignin degradation products that are inhibitory to downstream saccharification enzymes. The saccharification enzyme cocktail is made up of endo-cellulase, exo-cellulase and beta-glucosidase enzymes, whose role is to cleave cellulose polymers into glucose monomers. Specifically, endo-cellulase and exo-cellulase enzymes cleave cellulose chains in the middle and at the end, resulting in cellobiose molecules, which are hydrolyzed into glucose by beta-glucosidase. Unfortunately, degradation compounds generated during pretreatment inhibit the saccharification enzyme cocktail. Various research groups have identified specific classes of inhibitors formed during biomass pretreatment and have studied their inhibitory effect on the saccharification cocktail. These various research groups prepared surrogate solutions in an attempt to

  16. Modelling and L1 Adaptive Control of Temperature in Biomass Pretreatment

    DEFF Research Database (Denmark)

    Prunescu, Remus Mihail; Blanke, Mogens; Sin, Gürkan

    2013-01-01

    Biomass steam pretreatment is a key process in converting agricultural wastes to bioethanol. The pretreatment occurs in a large pressurized tank called a thermal reactor. Two key parameters influence the successfulness of the process: the reactor temperature, and the retention time. A particle pu...

  17. Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Humbird, D.; Davis, R.; Tao, L.; Kinchin, C.; Hsu, D.; Aden, A.; Schoen, P.; Lukas, J.; Olthof, B.; Worley, M.; Sexton, D.; Dudgeon, D.

    2011-03-01

    This report describes one potential biochemical ethanol conversion process, conceptually based upon core conversion and process integration research at NREL. The overarching process design converts corn stover to ethanol by dilute-acid pretreatment, enzymatic saccharification, and co-fermentation. Building on design reports published in 2002 and 1999, NREL, together with the subcontractor Harris Group Inc., performed a complete review of the process design and economic model for the biomass-to-ethanol process. This update reflects NREL's current vision of the biochemical ethanol process and includes the latest research in the conversion areas (pretreatment, conditioning, saccharification, and fermentation), optimizations in product recovery, and our latest understanding of the ethanol plant's back end (wastewater and utilities). The conceptual design presented here reports ethanol production economics as determined by 2012 conversion targets and 'nth-plant' project costs and financing. For the biorefinery described here, processing 2,205 dry ton/day at 76% theoretical ethanol yield (79 gal/dry ton), the ethanol selling price is $2.15/gal in 2007$.

  18. Optimization of Saccharification Conditions of Lignocellulosic Biomass under Alkaline Pre-Treatment and Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    Rafał Łukajtis

    2018-04-01

    Full Text Available Pre-treatment is a significant step in the production of second-generation biofuels from waste lignocellulosic materials. Obtaining biofuels as a result of fermentation processes requires appropriate pre-treatment conditions ensuring the highest possible degree of saccharification of the feed material. An influence of the following process parameters were investigated for alkaline pre-treatment of Salix viminalis L.: catalyst concentration (NaOH, temperature, pre-treatment time and granulation. For this purpose, experiments were carried out in accordance to the Box-Behnken design for four factors. In the saccharification process of the pre-treated biomass, cellulolytic enzymes immobilized on diatomaceous earth were used. Based on the obtained results, a mathematical model for the optimal conditions of alkaline pre-treatment prediction is proposed. The optimal conditions of alkaline pre-treatment are established as follows: granulation 0.75 mm, catalyst concentration 7%, pre-treatment time 6 h and temperature 65 °C if the saccharification efficiency and cost analysis are considered. An influence of the optimized pre-treatment on both the chemical composition and structural changes for six various lignocellulosic materials (energetic willow, energetic poplar, beech, triticale, meadow grass, corncobs was investigated. SEM images of raw and pre-treated biomass samples are included in order to follow the changes in the biomass structure during hydrolysis.

  19. Oxytocin and social pretreatment have similar effects on processing of negative emotional faces in healthy adult males

    Directory of Open Access Journals (Sweden)

    Anna eKis

    2013-08-01

    Full Text Available Oxytocin has been shown to affect several aspects of human social cognition, including facial emotion processing. There is also evidence that social stimuli (such as eye-contact can effectively modulate endogenous oxytocin levels.In the present study we directly tested whether intranasal oxytocin administration and pre-treatment with social stimuli had similar effects on face processing at the behavioural level. Subjects (N=52 healthy adult males were presented with a set of faces with expressions of different valence (negative, neutral, positive following different types of pretreatment (oxytocin – OT or placebo – PL and social interaction – Soc or no social interaction – NSoc, N=13 in each and were asked to rate all faces for perceived emotion and trustworthiness. On the next day subjects’ recognition memory was tested on a set of neutral faces and additionally they had to again rate each face for trustworthiness and emotion.Subjects in both the OT and the Soc pretreatment group (as compared to the PL and to the NSoc groups gave higher emotion and trustworthiness scores for faces with negative emotional expression. Moreover, 24 h later, subjects in the OT and Soc groups (unlike in control groups gave lower trustworthiness scores for previously negative faces, than for faces previously seen as emotionally neutral or positive.In sum these results provide the first direct evidence of the similar effects of intranasal oxytocin administration and social stimulation on the perception of negative facial emotions as well as on the delayed recall of negative emotional information.

  20. Cell-wall structural changes in wheat straw pretreated for bioethanol production

    Science.gov (United States)

    Jan B. Kristensen; G. Thygesen Lisbeth; Claus Felby; Henning Jorgensen; Thomas Elder

    2008-01-01

    Pretreatment is an essential step in the enzymatic hydrolysis of biomass and subsequent production of bioethanol. Recent results indicate that only a mild pretreatment is necessary in an industrial, economically feasible system. The Integrated Biomass Utilisation System hydrothermal pretreatment process has previously been shown to be effective in preparing wheat straw...

  1. Autohydrolysis Pretreatment of Lignocellulosic Biomass for Bioethanol Production

    Science.gov (United States)

    Han, Qiang

    Autohydrolysis, a simple and environmental friendly process, has long been studied but often abandoned as a financially viable pretreatment for bioethanol production due to the low yields of fermentable sugars at economic enzyme dosages. The introduction of mechanical refining can generate substantial improvements for autohydrolysis process, making it an attractive pretreatment technology for bioethanol commercialization. In this study, several lignocellulosic biomass including wheat straw, switchgrass, corn stover, waste wheat straw have been subjected to autohydrolysis pretreatment followed by mechanical refining to evaluate the total sugar recovery at affordable enzyme dosages. Encouraging results have been found that using autohydrolysis plus refining strategy, the total sugar recovery of most feedstock can be as high as 76% at 4 FPU/g enzymes dosages. The mechanical refining contributed to the improvement of enzymatic sugar yield by as much as 30%. Three non-woody biomass (sugarcane bagasse, wheat straw, and switchgrass) and three woody biomass (maple, sweet gum, and nitens) have been subjected to autohydrolysis pretreatment to acquire a fundamental understanding of biomass characteristics that affect the autohydrolysis and the following enzymatic hydrolysis. It is of interest to note that the nonwoody biomass went through substantial delignification during autohydrolysis compared to woody biomass due to a significant amount of p-coumaric acid and ferulic acid. It has been found that hardwood which has a higher S/V ratio in the lignin structure tends to have a higher total sugar recovery from autohydrolysis pretreatment. The economics of bioethanol production from autohydrolysis of different feedstocks have been investigated. Regardless of different feedstocks, in the conventional design, producing bioethanol and co-producing steam and power, the minimum ethanol revenues (MER) required to generate a 12% internal rate of return (IRR) are high enough to

  2. Pretreatment of different waste streams for improvement in biogas production; Foerbehandlingsteknikers betydelse foer oekat biogasutbyte

    Energy Technology Data Exchange (ETDEWEB)

    Sarvari Horvath, Ilona (Hoegskolan i Boraas (Sweden)); del Pilar Castillo, Maria (JTI (Sweden)); Loren, Anders; Brive, Lena; Ekendahl, Susanne; Nordman, Roger (SP, Boraas (Sweden)); Kanerot, Mija (Boraas Energi och Miljoe AB (Sweden))

    2010-07-01

    Biological breakdown of organic municipal and industrial waste to biogas is already in use today. The technology is of outmost importance to attain the environmental goals that our society has set regarding to sustainable development. Of decisive economic importance is the ability to obtain an increased amount of biogas from the same amount of substrate. Alternative resources for biogas production are at the same time of great interest in order to enable a large expansion of biogas production. The goal of applying a suitable pre-treatment step before anaerobic digestion is to open up the molecular structure of inaccessible biopolymers in order to facilitate access to the carbon for microorganisms involved in biological breakdown and fermentation to biogas. Our study shows that introducing a pretreatment step opens new perspectives for biogas production. Treatment of paper residuals by steam explosion increased methane production up to 400 Nm3/ton dry matter, to a double amount of methane yield compared to that of untreated paper. A novel method for pretreatment with an environment-friendly solvent N-methylmorpholine-N-oxide (NMMO) was also tested on lignocellulose-rich waste fractions from forest and agricultural. The NMMO-treatment increased the methane yields of spruce chips and triticale straw by 25 times (250 Nm3/ton dry matter), and by 6 times (200 Nm3/ton dry matter), respectively, compared to that of the untreated materials. Keratin-rich feather waste yielded around 200 Nm3 methane/ton dry matter, which could be increased to 450 Nm3/ton after enzymatic treatment and to 360 Nm3/ton after either chemical treatment with lime, or after biological treatment with a recombinant bacterial strain of Bacillus megaterium. However, the gain in increased amount of methane after a pretreatment step should be weighted against a possible increase in energy usage generated by the pretreatment. We have therefore performed a case study in which the energy balance for a biogas

  3. Torque measurements reveal large process differences between materials during high solid enzymatic hydrolysis of pretreated lignocellulose

    Directory of Open Access Journals (Sweden)

    Palmqvist Benny

    2012-08-01

    Full Text Available Abstract Background A common trend in the research on 2nd generation bioethanol is the focus on intensifying the process and increasing the concentration of water insoluble solids (WIS throughout the process. However, increasing the WIS content is not without problems. For example, the viscosity of pretreated lignocellulosic materials is known to increase drastically with increasing WIS content. Further, at elevated viscosities, problems arise related to poor mixing of the material, such as poor distribution of the enzymes and/or difficulties with temperature and pH control, which results in possible yield reduction. Achieving good mixing is unfortunately not without cost, since the power requirements needed to operate the impeller at high viscosities can be substantial. This highly important scale-up problem can easily be overlooked. Results In this work, we monitor the impeller torque (and hence power input in a stirred tank reactor throughout high solid enzymatic hydrolysis (Arundo donax and spruce. Two different process modes were evaluated, where either the impeller speed or the impeller power input was kept constant. Results from hydrolysis experiments at a fixed impeller speed of 10 rpm show that a very rapid decrease in impeller torque is experienced during hydrolysis of pretreated arundo (i.e. it loses its fiber network strength, whereas the fiber strength is retained for a longer time within the spruce material. This translates into a relatively low, rather WIS independent, energy input for arundo whereas the stirring power demand for spruce is substantially larger and quite WIS dependent. By operating the impeller at a constant power input (instead of a constant impeller speed it is shown that power input greatly affects the glucose yield of pretreated spruce whereas the hydrolysis of arundo seems unaffected. Conclusions The results clearly highlight the large differences between the arundo and spruce materials, both in terms of

  4. Conversion of alkaline pretreated empty palm fruit bunch (EPFB) to phenols

    International Nuclear Information System (INIS)

    Nor Aishah Saidina Amin; Roslindawati Haron

    2010-01-01

    Various efforts on green chemistry are being directed at producing renewable chemicals. Chemicals derived from biomass can be the basis for building blocks in the chemicals industry. Phenols, traditionally produced from petroleum, can be derived from biomass for naturally-sourced solvents. Lignocellulose biomass consists of cellulose, hemicelluloses and lignin. Lignocellulose components can be altered by various chemical pretreatment methods. EFB contains about 60% cellulose and almost equal portions of lignin and hemicelluloses. Pretreatment of EFB fragmentized and degraded the lignocellulose structure in order to produce chemicals under thermochemical process. In this work, EFB was chemically pretreated with different sodium hydroxide (NaOH) concentrations to concentrated lignocellulose before being pyrolyzed to produce solid, gas and liquid products. Pyrolysis was conducted after the pretreatment step to evaluate the effects of pretreatment process on production and compositions of the bio-oil. The conversions of EFB were reported to be 61wt%, 47wt% and 42 wt%, after pretreatment with 5 wt%, 15 wt% and 25 wt%,NaOH concentrations, respectively. GCMS analysis results revealed the crude bio-oil contained dominantly phenol. Pyrolysis of the alkaline pretreated EFB seemed potential to produce biomass-based phenols. (author)

  5. Cell-wall structural changes in wheat straw pretreated for bioethanol production

    Directory of Open Access Journals (Sweden)

    Jørgensen Henning

    2008-04-01

    Full Text Available Abstract Background Pretreatment is an essential step in the enzymatic hydrolysis of biomass and subsequent production of bioethanol. Recent results indicate that only a mild pretreatment is necessary in an industrial, economically feasible system. The Integrated Biomass Utilisation System hydrothermal pretreatment process has previously been shown to be effective in preparing wheat straw for these processes without the application of additional chemicals. In the current work, the effect of the pretreatment on the straw cell-wall matrix and its components are characterised microscopically (atomic force microscopy and scanning electron microscopy and spectroscopically (attenuated total reflectance Fourier transform infrared spectroscopy in order to understand this increase in digestibility. Results The hydrothermal pretreatment does not degrade the fibrillar structure of cellulose but causes profound lignin re-localisation. Results from the current work indicate that wax has been removed and hemicellulose has been partially removed. Similar changes were found in wheat straw pretreated by steam explosion. Conclusion Results indicate that hydrothermal pretreatment increases the digestibility by increasing the accessibility of the cellulose through a re-localisation of lignin and a partial removal of hemicellulose, rather than by disruption of the cell wall.

  6. Improving biogas production from microalgae by enzymatic pretreatment.

    Science.gov (United States)

    Passos, Fabiana; Hom-Diaz, Andrea; Blanquez, Paqui; Vicent, Teresa; Ferrer, Ivet

    2016-01-01

    In this study, enzymatic pretreatment of microalgal biomass was investigated under different conditions and evaluated using biochemical methane potential (BMP) tests. Cellulase, glucohydrolase and an enzyme mix composed of cellulase, glucohydrolase and xylanase were selected based on the microalgae cell wall composition (cellulose, hemicellulose, pectin and glycoprotein). All of them increased organic matter solubilisation, obtaining high values already after 6h of pretreatment with an enzyme dose of 1% for cellulase and the enzyme mix. BMP tests with pretreated microalgae showed a methane yield increase of 8 and 15% for cellulase and the enzyme mix, respectively. Prospective research should evaluate enzymatic pretreatments in continuous anaerobic reactors so as to estimate the energy balance and economic cost of the process. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Effects of drying pretreatment and particle size adjustment on the composting process of discarded flue-cured tobacco leaves.

    Science.gov (United States)

    Zhao, Gui-Hong; Yu, Yan-Ling; Zhou, Xiang-Tong; Lu, Bin-Yu; Li, Zi-Mu; Feng, Yu-Jie

    2017-05-01

    The main characteristic of discarded flue-cured tobacco leaves is their high nicotine content. Aerobic composting is an effective method to decrease the nicotine level in tobacco leaves and stabilize tobacco wastes. However, high levels of nicotine in discarded flue-cured tobacco leaves complicate tobacco waste composting. This work proposes a drying pretreatment process to reduce the nicotine content in discarded flue-cured tobacco leaves and thus enhance its carbon-to-nitrogen ratio to a suitable level for composting. The effect of another pretreatment method, particle size adjustment, on composting efficiency was also tested in this work. The results indicated that the air-dried (nicotine content: 1.35%) and relatively long discarded flue-cured tobacco leaves (25 mm) had a higher composting efficiency than damp (nicotine content: 1.57%) and short discarded flue-cured tobacco leaves (15 mm). When dry/25 mm discarded flue-cured tobacco leaves mixed with tobacco stems in an 8:2 ratio was composted at a temperature above 55 °C for 9 days, the nicotine content dropped from 1.29% to 0.28%. Since the discarded flue-cured tobacco leaves was successfully composted to a fertile and harmless material, the germination index values increased to 85.2%. The drying pretreatment and particle size adjustment offered ideal physical and chemical conditions to support microbial growth and bioactivity during the composting process, resulting in efficient conversion of discarded flue-cured tobacco leaves into a high quality and mature compost.

  8. Process analysis and optimization of simultaneous saccharification and co-fermentation of ethylenediamine-pretreated corn stover for ethanol production.

    Science.gov (United States)

    Qin, Lei; Zhao, Xiong; Li, Wen-Chao; Zhu, Jia-Qing; Liu, Li; Li, Bing-Zhi; Yuan, Ying-Jin

    2018-01-01

    Improving ethanol concentration and reducing enzyme dosage are main challenges in bioethanol refinery from lignocellulosic biomass. Ethylenediamine (EDA) pretreatment is a novel method to improve enzymatic digestibility of lignocellulose. In this study, simultaneous saccharification and co-fermentation (SSCF) process using EDA-pretreated corn stover was analyzed and optimized to verify the constraint factors on ethanol production. Highest ethanol concentration was achieved with the following optimized SSCF conditions at 6% glucan loading: 12-h pre-hydrolysis, 34 °C, pH 5.4, and inoculum size of 5 g dry cell/L. As glucan loading increased from 6 to 9%, ethanol concentration increased from 33.8 to 48.0 g/L, while ethanol yield reduced by 7%. Mass balance of SSCF showed that the reduction of ethanol yield with the increasing solid loading was mainly due to the decrease of glucan enzymatic conversion and xylose metabolism of the strain. Tween 20 and BSA increased ethanol concentration through enhancing enzymatic efficiency. The solid-recycled SSCF process reduced enzyme dosage by 40% (from 20 to 12 mg protein/g glucan) to achieve the similar ethanol concentration (~ 40 g/L) comparing to conventional SSCF. Here, we established an efficient SSCF procedure using EDA-pretreated biomass. Glucose enzymatic yield and yeast viability were regarded as the key factors affecting ethanol production at high solid loading. The extensive analysis of SSCF would be constructive to overcome the bottlenecks and improve ethanol production in cellulosic ethanol refinery.

  9. Effects of Pretreatment on the Structure And Properties of Electroless Nickel Coatings

    DEFF Research Database (Denmark)

    Møller, Per; Deng, Hong

    1994-01-01

    The pretreatment process can significantly affect the corrosion resistance of electroless nickel (EN) coatings One of the most important reasons is that different pretreatment processes can give different surface morphologies of the substrate. The scanning electron microscope (SEM) and the scanni...

  10. Ethanol production from residual wood chips of cellulose industry: acid pretreatment investigation, hemicellulosic hydrolysate fermentation, and remaining solid fraction fermentation by SSF process.

    Science.gov (United States)

    Silva, Neumara Luci Conceição; Betancur, Gabriel Jaime Vargas; Vasquez, Mariana Peñuela; Gomes, Edelvio de Barros; Pereira, Nei

    2011-04-01

    Current research indicates the ethanol fuel production from lignocellulosic materials, such as residual wood chips from the cellulose industry, as new emerging technology. This work aimed at evaluating the ethanol production from hemicellulose of eucalyptus chips by diluted acid pretreatment and the subsequent fermentation of the generated hydrolysate by a flocculating strain of Pichia stipitis. The remaining solid fraction generated after pretreatment was subjected to enzymatic hydrolysis, which was carried out simultaneously with glucose fermentation [saccharification and fermentation (SSF) process] using a strain of Saccharomyces cerevisiae. The acid pretreatment was evaluated using a central composite design for sulfuric acid concentration (1.0-4.0 v/v) and solid to liquid ratio (1:2-1:4, grams to milliliter) as independent variables. A maximum xylose concentration of 50 g/L was obtained in the hemicellulosic hydrolysate. The fermentation of hemicellulosic hydrolysate and the SSF process were performed in bioreactors and the final ethanol concentrations of 15.3 g/L and 28.7 g/L were obtained, respectively.

  11. COMPARISON OF PRETREATMENT STRATEGIES FOR CONVERSION OF COCONUT HUSK FIBER TO FERMENTABLE SUGARS

    Directory of Open Access Journals (Sweden)

    Teck Y. Ding,

    2012-02-01

    Full Text Available In the present study, coconut husk was employed as biomass feedstock for production of bioethanol, due to its abundance in Malaysia. Due to the complex structures of coconut husk, a pretreatment process is crucial in extracting fermentable sugars from the embedded cellulose matrix for subsequent ethanol fermentation process. The ground coconut husk was subjected to three different pretreatment processes inclusive of thermal, chemical, and microwave-assisted-alkaline techniques, prior to enzymatic hydrolysis and fermentation process. The composition profile of coconut husk was significantly altered upon the microwave-assisted-alkaline treatment as compared to the untreated sample, with the cellulose content increasing from 18-21% to 38-39% while lignin content decreased from 46-53% to 31-33%. Among the pretreatment methods applied, enzymatic hydrolysis of coconut husk pretreated by microwave-assisted-alkaline method recorded the highest yield of fermentable sugars, 0.279 g sugar/g substrate. SEM imaging showed the obvious and significant disruption of coconut husks’ structure after microwave-assisted-alkaline pretreatment. In conclusion, by employing suitable pretreatment technique in treating the lignocellulosic materials of coconut husk, the extracted fermentable sugar is a potential substrate for bioethanol production.

  12. Pretreatment of Real Wastewater from the Chocolate Manufacturing Industry through an Integrated Process of Electrocoagulation and Sand Filtration

    OpenAIRE

    García-Morales, Marco A.; Juárez, Julio César González; Martínez-Gallegos, Sonia; Roa-Morales, Gabriela; Peralta, Ever; del Campo López, Eduardo Martin; Barrera-Díaz, Carlos; Miranda, Verónica Martínez; Blancas, Teresa Torres

    2018-01-01

    The purpose of this study was to evaluate the efficiency of removal of suspended solids in terms of turbidity, color, and chemical oxygen demand (COD) when integrating the electrocoagulation process using aluminum sacrificial anodes and the sand filtration process as a pretreatment of wastewater from the chocolate manufacturing plant in Toluca, México. Wastewater from the chocolate manufacturing industry used in this study is classified as nontoxic, but is characterized as having a high conte...

  13. Extrusion Pretreatment of Lignocellulosic Biomass: A Review

    Directory of Open Access Journals (Sweden)

    Jun Zheng

    2014-10-01

    Full Text Available Bioconversion of lignocellulosic biomass to bioethanol has shown environmental, economic and energetic advantages in comparison to bioethanol produced from sugar or starch. However, the pretreatment process for increasing the enzymatic accessibility and improving the digestibility of cellulose is hindered by many physical-chemical, structural and compositional factors, which make these materials difficult to be used as feedstocks for ethanol production. A wide range of pretreatment methods has been developed to alter or remove structural and compositional impediments to (enzymatic hydrolysis over the last few decades; however, only a few of them can be used at commercial scale due to economic feasibility. This paper will give an overview of extrusion pretreatment for bioethanol production with a special focus on twin-screw extruders. An economic assessment of this pretreatment is also discussed to determine its feasibility for future industrial cellulosic ethanol plant designs.

  14. Use of anaerobic hydrolysis pretreatment to enhance ultrasonic disintegration of excess sludge.

    Science.gov (United States)

    Li, Xianjin; Zhu, Tong; Shen, Yang; Chai, Tianyu; Xie, Yuanhua; You, Meiyan; Wang, Youzhao

    2016-01-01

    To improve the excess sludge disintegration efficiency, reduce the sludge disintegration cost, and increase sludge biodegradability, a combined pretreatment of anaerobic hydrolysis (AH) and ultrasonic treatment (UT) was proposed for excess sludge. Results showed that AH had an advantage in dissolving flocs, modifying sludge characteristics, and reducing the difficulty of sludge disintegration, whereas UT was advantageous in damaging cell walls, releasing intracellular substances, and decomposing macromolecular material. The combined AH-UT process was an efficient method for excess sludge pretreatment. The optimized solution involved AH for 3 days, followed by UT for 10 min. After treatment, chemical oxygen demand, protein, and peptidoglycan concentrations reached 3,949.5 mg O2/L, 752.5 mg/L and 619.1 mg/L, respectively. This work has great significance for further engineering applications, namely, reducing energy consumption, increasing the sludge disintegration rate, and improving the biochemical properties of sludge.

  15. Treatment of textile dyehouse effluent using ceramic membrane based process in combination with chemical pretreatment.

    Science.gov (United States)

    Bhattacharya, Priyankari; Ghosh, Sourja; Majumdar, Swachchha; Bandyopadhyay, Sibdas

    2013-10-01

    Treatment of highly concentrated dyebath effluent and comparatively dilute composite effluent having mixture of various reactive dyes collected from a cotton fabric dyeing unit was undertaken in the present study. Ceramic microfiltration membrane prepared from a cost effective composition of alumina and clay was used. Prior to microfiltration, a chemical pretreatment was carried out with aluminium sulphate in combination with a polymeric retention aid. An optimum dose of 100 mg/L of aluminium sulphate and 1 ml/L of a commercial flocculant Afilan RAMF was found effective for dye removal (> 98%) from the synthetic solutions of reactive dyes with initial concentration of 150 mg/L in both the single component and two component systems. In the microfiltration study, effect of operating pressure in the permeate flux was observed for both the pretreated and untreated effluents and permeate samples were analyzed for dye concentration, COD, turbidity, TSS, etc. during constant pressure filtration. About 98-99% removal of dyes was obtained in the combined process with COD reduction of 54-64%.

  16. Effect of pretreatment of hydrothermally processed rice straw with laccase-displaying yeast on ethanol fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Nakanishi, Akihito; Bae, Jun Gu; Fukai, Kotaro; Tokumoto, Naoki; Kuroda, Kouichi; Ogawa, Jun; Shimizu, Sakayu; Ueda, Mitsuyoshi [Kyoto Univ. (Japan). Div. of Applied Life Sciences; Nakatani, Masato [Daiwa Kasei, Shiga (Japan)

    2012-05-15

    A gene encoding laccase I was identified and cloned from the white-rot fungus Trametes sp. Ha1. Laccase I contained 10 introns and an original secretion signal sequence. After laccase I without introns was prepared by overlapping polymerase chain reaction, it was inserted into expression vector pULD1 for yeast cell surface display. The oxidation activity of a laccase-I-displaying yeast as a whole-cell biocatalyst was examined with 2,2{sup '}-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), and the constructed yeast showed a high oxidation activity. After the pretreatment of hydrothermally processed rice straw (HPRS) with laccase-I-displaying yeast with ABTS, fermentation was conducted with yeast codisplaying endoglucanase, cellobiohydrolase, and {beta}-glucosidase with HPRS. Fermentation of HPRS treated with laccase-I-displaying yeast was performed with 1.21-fold higher activities than those of HPRS treated with control yeast. The results indicated that pretreatment with laccase-I-displaying yeast with ABTS was effective for direct fermentation of cellulosic materials by yeast codisplaying endoglucanase, cellobiohydrolase, and {beta}-glucosidase. (orig.)

  17. Bioconversion of paper mill sludge to bioethanol in the presence of accelerants or hydrogen peroxide pretreatment.

    Science.gov (United States)

    Gurram, Raghu Nandan; Al-Shannag, Mohammad; Lecher, Nicholas Joshua; Duncan, Shona M; Singsaas, Eric Lawrence; Alkasrawi, Malek

    2015-09-01

    In this study we investigated the technical feasibility of convert paper mill sludge into fuel ethanol. This involved the removal of mineral fillers by using either chemical pretreatment or mechanical fractionation to determine their effects on cellulose hydrolysis and fermentation to ethanol. In addition, we studied the effect of cationic polyelectrolyte (as accelerant) addition and hydrogen peroxide pretreatment on enzymatic hydrolysis and fermentation. We present results showing that removing the fillers content (ash and calcium carbonate) from the paper mill sludge increases the enzymatic hydrolysis performance dramatically with higher cellulose conversion at faster rates. The addition of accelerant and hydrogen peroxide pretreatment further improved the hydrolysis yields by 16% and 25% (g glucose / g cellulose), respectively with the de-ashed sludge. The fermentation process of produced sugars achieved up to 95% of the maximum theoretical ethanol yield and higher ethanol productivities within 9h of fermentation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Identification of Key Factors Involved in the Biosorption of Patulin by Inactivated Lactic Acid Bacteria (LAB Cells.

    Directory of Open Access Journals (Sweden)

    Ling Wang

    Full Text Available The purpose of this study was to identify the key factors involved in patulin adsorption by heat-inactivated lactic acid bacteria (LAB cells. For preventing bacterial contamination, a sterilization process was involved in the adsorption process. The effects of various physical, chemical, and enzymatic pre-treatments, simultaneous treatments, and post-treatments on the patulin adsorption performances of six LAB strains were evaluated. The pre-treated cells were characterized by scanning electron microscopy (SEM. Results showed that the removal of patulin by viable cells was mainly based on adsorption or degradation, depending on the specific strain. The adsorption abilities were widely increased by NaOH and esterification pre-treatments, and reduced by trypsin, lipase, iodate, and periodate pre-treatments. Additionally, the adsorption abilities were almost maintained at pH 2.2-4.0, and enhanced significantly at pH 4.0-6.0. The effects of sodium and magnesium ions on the adsorption abilities at pH 4 were slight and strain-specific. A lower proportion of patulin was released from the strain with higher adsorption ability. Analyses revealed that the physical structure of peptidoglycan was not a principal factor. Vicinal OH and carboxyl groups were not involved in patulin adsorption, while alkaline amino acids, thiol and ester compounds were important for patulin adsorption. Additionally, besides hydrophobic interaction, electrostatic interaction also participated in patulin adsorption, which was enhanced with the increase in pH (4.0-6.0.

  19. Identification of Key Factors Involved in the Biosorption of Patulin by Inactivated Lactic Acid Bacteria (LAB) Cells.

    Science.gov (United States)

    Wang, Ling; Wang, Zhouli; Yuan, Yahong; Cai, Rui; Niu, Chen; Yue, Tianli

    2015-01-01

    The purpose of this study was to identify the key factors involved in patulin adsorption by heat-inactivated lactic acid bacteria (LAB) cells. For preventing bacterial contamination, a sterilization process was involved in the adsorption process. The effects of various physical, chemical, and enzymatic pre-treatments, simultaneous treatments, and post-treatments on the patulin adsorption performances of six LAB strains were evaluated. The pre-treated cells were characterized by scanning electron microscopy (SEM). Results showed that the removal of patulin by viable cells was mainly based on adsorption or degradation, depending on the specific strain. The adsorption abilities were widely increased by NaOH and esterification pre-treatments, and reduced by trypsin, lipase, iodate, and periodate pre-treatments. Additionally, the adsorption abilities were almost maintained at pH 2.2-4.0, and enhanced significantly at pH 4.0-6.0. The effects of sodium and magnesium ions on the adsorption abilities at pH 4 were slight and strain-specific. A lower proportion of patulin was released from the strain with higher adsorption ability. Analyses revealed that the physical structure of peptidoglycan was not a principal factor. Vicinal OH and carboxyl groups were not involved in patulin adsorption, while alkaline amino acids, thiol and ester compounds were important for patulin adsorption. Additionally, besides hydrophobic interaction, electrostatic interaction also participated in patulin adsorption, which was enhanced with the increase in pH (4.0-6.0).

  20. Selective pyrolysis of paper mill sludge by using pretreatment processes to enhance the quality of bio-oil and biochar products

    International Nuclear Information System (INIS)

    Reckamp, Joseph M.; Garrido, Rene A.; Satrio, Justinus A.

    2014-01-01

    Paper mill sludge (PMS) is a residual biomass that is generated at paper mills in large quantities. Currently, PMS is commonly disposed in landfills, which causes environmental issues through chemical leaching and greenhouse gas production. In this research, we are exploring the potential of fast pyrolysis process for converting PMS into useful bio-oil and biochar products. We demonstrate that by subjecting PMS to a combination of acid hydrolysis and torrefaction pre-treatment processes it is possible to alter the physicochemical properties and composition of the feedstock material. Fast pyrolysis of pretreated PMS produced bio-oil with significantly higher selectivity to levoglucosenone and significantly reduced the amount of ketone, aldehyde, and organic acid components. Pretreatment of PMS with combined 4% mass fraction phosphoric acid hydrolysis and 220 °C torrefaction processed prior to fast pyrolysis resulted in a 17 times increase of relative selectivity towards levoglucosenone in bio-oil product along with a reduction of acids, ketones, and aldehydes combined from 21 % to 11 %. Biochar, produced in higher yield, has characteristics that potentially make the solid byproduct ideal for soil amendment agent or sorbent material. This work reveals a promising process system to convert PMS waste into useful bio-based products. More in-depth research is required to gather more data information for assessing the economic and sustainability aspects of the process. - Highlights: • Acid hydrolysis and torrefaction reduce bio-oil yield, but improve quality. • Dilute acid conditions provide optimal treatment for bio-oil quality and yield. • Pyrolysis of treated PMS produces high selectivity to levoglucosenone formation. • Treated PMS produces bio-oil with reduced acid, ketone, and aldehyde content. • Pyrolysis of treated PMS produces biochar with low volatile matter in high yield

  1. Getting Involved in the IEP Process

    Science.gov (United States)

    Kowalski, Ellen; Lieberman, Lauren J.; Daggett, Sara

    2006-01-01

    Although, in many districts, physical educators are integral members of the Individualized Education Program (designed for students with disabilities such as Down syndrome and autism), in other districts, physical educators are only partially involved in the process or are not given the opportunity to be involved at all. However, the physical…

  2. Delayed brain ischemia tolerance induced by electroacupuncture pretreatment is mediated via MCP-induced protein 1

    Science.gov (United States)

    2013-01-01

    Background Emerging studies have demonstrated that pretreatment with electroacupuncture (EA) induces significant tolerance to focal cerebral ischemia. The present study seeks to determine the involvement of monocyte chemotactic protein-induced protein 1 (MCPIP1), a recently identified novel modulator of inflammatory reactions, in the cerebral neuroprotection conferred by EA pretreatment in the animal model of focal cerebral ischemia and to elucidate the mechanisms of EA pretreatment-induced ischemic brain tolerance. Methods Twenty-four hours after the end of the last EA pretreatment, focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) for 90 minutes in male C57BL/6 mice and MCPIP1 knockout mice. Transcription and expression of MCPIP1 gene was monitored by qRT-PCR, Western blot and immunohistochemistry. The neurobehavioral scores, infarction volumes, proinflammatory cytokines and leukocyte infiltration in brain and NF-κB signaling were evaluated after ischemia/reperfusion. Results MCPIP1 protein and mRNA levels significantly increased specifically in mouse brain undergoing EA pretreatment. EA pretreatment significantly attenuated the infarct volume, neurological deficits, upregulation of proinflammatory cytokines and leukocyte infiltration in the brain of wild-type mice after MCAO compared with that of the non-EA group. MCPIP1-deficient mice failed to evoke EA pretreatment-induced tolerance compared with that of the control MCPIP1 knockout group without EA treatment. Furthermore, the activation of NF-κB signaling was significantly reduced in EA-pretreated wild-type mice after MCAO compared to that of the non-EA control group and MCPIP1-deficient mice failed to confer the EA pretreatment-induced inhibition of NF-κB signaling after MCAO. Conclusions Our data demonstrated that MCPIP1 deficiency caused significant lack of EA pretreatment-induced cerebral protective effects after MCAO compared with the control group and that MCPIP1 is

  3. Use of artificial neuronal networks for prediction of the control parameters in the process of anaerobic digestion with thermal pretreatment.

    Science.gov (United States)

    Flores-Asis, Rita; Méndez-Contreras, Juan M; Juárez-Martínez, Ulises; Alvarado-Lassman, Alejandro; Villanueva-Vásquez, Daniel; Aguilar-Lasserre, Alberto A

    2018-04-19

    This article focuses on the analysis of the behavior patterns of the variables involved in the anaerobic digestion process. The objective is to predict the impact factor and the behavior pattern of the variables, i.e., temperature, pH, volatile solids (VS), total solids, volumetric load, and hydraulic residence time, considering that these are the control variables for the conservation of the different groups of anaerobic microorganisms. To conduct the research, samples of physicochemical sludge were taken from a water treatment plant in a poultry processing factory, and, then, the substrate was characterized, and a thermal pretreatment was used to accelerate the hydrolysis process. The anaerobic digestion process was analyzed in order to obtain experimental data of the control variables and observe their impact on the production of biogas. The results showed that the thermal pre-hydrolysis applied at 90°C for 90 min accelerated the hydrolysis phase, allowing a significant 52% increase in the volume of methane produced. An artificial neural network was developed, and it was trained with the database obtained by monitoring the anaerobic digestion process. The results obtained from the artificial neural network showed that there is an adjustment between the real values and the prediction of validation based on 60 samples with a 96.4% coefficient of determination, and it was observed that the variables with the major impact on the process were the loading rate and VS, with impact factors of 36% and 23%, respectively.

  4. Pre-treatment of oil palm fronds biomass for gasification

    Directory of Open Access Journals (Sweden)

    Sulaiman Shaharin Anwar

    2017-01-01

    Full Text Available Oil Palm Fronds (OPF has been proven as one of the potential types of biomass feedstock for power generation. The low ash content and high calorific value are making OPF an attractive source for gasification. The objective of this study is to investigate the effects of pre-treatments of OPF residual on gasification. The pre-treatments included the briquetting process and extensive drying of OPF which are studied separately. In briquetting process, the OPF were mixed with some portions of paper as an additives, leaflets, and water, to form a soupy slurry. The extensive drying of OPF needs to cut down OPF in 4–6 cm particle size and left to dry in the oven at 150°C for 24 hours. Gasification process was carried out at the end of each of the pre-treated processes. It was found that the average gas composition obtained from briquetting process was 8.07%, 2.06%, 0.54%,and 11.02% for CO, H2, CH4, and CO2 respectively. A good composition of syngas was produced from extensive dried OPF, as 16.48%, 4.03%, 0.91%,and 11.15% for CO, H2, CH4, and CO2 contents respectively. It can be concluded that pre-treatments improved the physical characteristics of biomass. The bulk density of biomass can be increased by briquetting but the stability of the structure is depending on the composition of briquette formulation. Furthermore, the stability of gasification process also depended on briquette density, mechanical strength, and formulation.

  5. Impact analysis of different chemical pre-treatments on colour of apple discs during drying process

    Directory of Open Access Journals (Sweden)

    Jasmina Lukinac

    2009-01-01

    Full Text Available The main purpose of this study was to compare colour changes of chemically pre-treated dried apple discs. Changes were observed by chromameter in L*a*b* colour model by using Minolta chromameter CR-400 and by image analysis system in RGB colour model. Apple discs variety "Gold Rush" were pre-treated and dried in laboratory tray drier at drying temperature 70 °C and at airflow velocity of 1.5 ms-1. Different chemical pre-treatments were applied on apple discs (dipping in 0.5% ascorbic acid solution; 0.3% L–cysteine solution; 0.1% 4–hexyl resorcinol solution and 1% sodium metabisulphite solution. Mean values of colour parameters, colour changes and correlation coefficients for apple discs were calculated for both colour models. The analysis showed statistically significant influence of pre-treatment method on total colour changes for both chosen colour models of dried apples. Calculated correlation coefficient between colour changes for used models was found to be 0.894. According to colour characteristics the best results were achieved when samples were pre-treated with 0.5% ascorbic acid solution. According to calculated results it was found that image analysis method as well as colorimetric method can be used to observe the colour changes on dried apple discs.

  6. Development and application of free pretreatment container steel

    Science.gov (United States)

    Yang, Y.; Liu, Y.; Han, B.; Wei, B.; Wang, S. Z.

    2017-12-01

    Due to economic and environmental advantages pre-treatment containers have good big development prospects, which can avoid shot blasting processes, and decrease the noise and dust pollution. By analyzing requirements of the container steel surface quality, target oxide scale structure of free pretreatment container steel has been determined. Trial process was carried out, and test results showed that the oxide scale achieved the desired objects, oxide scale with outer thin Fe3O4 layer and inner eutectoid α-Fe+Fe3O4. Salt spray test, second adhesion test, and modeling performance basically corroborated the container feasibility.

  7. Effects of Pretreatments in Convective Dehydration of Rosehip (Rosa eglanteria

    Directory of Open Access Journals (Sweden)

    Alejandra Mabellini

    2012-04-01

    Full Text Available The aim of this work was to experimentally determine drying curves for thin layer and bed drying of rosehip fruits, with and without pretreatments, to reduce processing times as a function of drying air operating variables, to propose dehydration kinetics of fruits and to determine its kinetic parameters for further use within drying simulation software. Fruits were pre-treated both chemically and mechanically, which included dipping the fruits in NaOH and ethyl oleate solutions; and cutting or perforating the fruit cuticle, respectively. Simulation models were then adopted to fit the kinetics drying data considering fruit volume shrinkage. These simple models minimized the calculation time during the simulation of deep-bed driers. Results show that pre-treatments reduced processing times up to 57%, and evaluated models satisfactorily predicted the drying of rosehip fruit. Effective mass diffusion coefficients were up to 4-fold greater when fruit was submitted to mechanical pretreatments.

  8. The pretreatment cost of a pyroprocess facility in Korea

    International Nuclear Information System (INIS)

    Kim, S. K.; Youn, S. R.; Lee, S. H.; Lee, H. J.; Ko, W. I.

    2015-01-01

    Shale gas still has many disadvantages such as significant technological difficulties and high costs even when the fracking technology is used to extract shale gas since shale gas is dispersed widely. Moreover, it is estimated that the shale gas can be used for about 60 years, which is comparable to the period estimated for oil deposits. Another concern is that the climate may change due to the discharge of harmful gas produced during the gas extraction process. PRIDE facility producing 10 ton/year uranium ingot was set as the cost object for the cost estimation, and it was possible to increase cost calculation's accuracy level since labor cost and expenses incurred in this facility were the costs incurred in actuality. In the end, First-In, First Out process costing method was used to calculate the pretreatment cost of pyroprocess. According to the cost calculation results, the pretreatment cost was estimated as $195/kgHM and the cost share of the pretreatment of pyroprocess was calculated as 20%. Accordingly, electrochemical reduction process is the process requires most cost, followed by the cost of electro-winning process

  9. The pretreatment cost of a pyroprocess facility in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S. K.; Youn, S. R.; Lee, S. H.; Lee, H. J.; Ko, W. I. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Shale gas still has many disadvantages such as significant technological difficulties and high costs even when the fracking technology is used to extract shale gas since shale gas is dispersed widely. Moreover, it is estimated that the shale gas can be used for about 60 years, which is comparable to the period estimated for oil deposits. Another concern is that the climate may change due to the discharge of harmful gas produced during the gas extraction process. PRIDE facility producing 10 ton/year uranium ingot was set as the cost object for the cost estimation, and it was possible to increase cost calculation's accuracy level since labor cost and expenses incurred in this facility were the costs incurred in actuality. In the end, First-In, First Out process costing method was used to calculate the pretreatment cost of pyroprocess. According to the cost calculation results, the pretreatment cost was estimated as $195/kgHM and the cost share of the pretreatment of pyroprocess was calculated as 20%. Accordingly, electrochemical reduction process is the process requires most cost, followed by the cost of electro-winning process.

  10. Effect of alkaline microwaving pretreatment on anaerobic digestion and biogas production of swine manure.

    Science.gov (United States)

    Yu, Tao; Deng, Yihuan; Liu, Hongyu; Yang, Chunping; Wu, Bingwen; Zeng, Guangming; Lu, Li; Nishimura, Fumitake

    2017-05-10

    Microwave assisted with alkaline (MW-A) condition was applied in the pretreatment of swine manure, and the effect of the pretreatment on anaerobic treatment and biogas production was evaluated in this study. The two main microwaving (MW) parameters, microwaving power and reaction time, were optimized for the pretreatment. Response surface methodology (RSM) was used to investigate the effect of alkaline microwaving process for manure pretreatment at various values of pH and energy input. Results showed that the manure disintegration degree was maximized of 63.91% at energy input of 54 J/g and pH of 12.0, and variance analysis indicated that pH value played a more important role in the pretreatment than in energy input. Anaerobic digestion results demonstrated that MW-A pretreatment not only significantly increased cumulative biogas production, but also shortened the duration for a stable biogas production rate. Therefore, the alkaline microwaving pretreatment could become an alternative process for effective treatment of swine manure.

  11. Different physical and chemical pretreatments of wheat straw for enhanced biobutanol production in simultaneous saccharification and fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Thirmal, Chumangalah; Dahman, Yaser [Department of Chemical Engineering, Ryerson University, Toronto, Ontario M5B 2K3 (Canada)

    2011-07-01

    The objective of this study is to increase butanol product yields using wheat straw as the biomass. First this study examined different pretreatment and saccharification processes to obtain the maximum sugar concentration. Three different physical and chemical pretreatment methods for the wheat straws were examined in the present work in comparison with physical pretreatment alone as a reference. This included water, acidic, and alkaline pretreatment. For all cases, physical pretreatment represented by 1 mm size reduction of the straws was applied prior to each pretreatment. Results showed that 13.91 g/L glucose concentration was produced from saccharification with just the physical pretreatment (i.e., no chemical pretreatment). This represented {approx}5-20 % lower sugar release in saccharification compared to the other three pretreatment processes. Saccharification with acid pretreatment obtained the highest sugar concentrations, which were 18.77 g/L glucose and 12.19 g/L xylose. Second this study produced butanol from simultaneous saccharification and fermentation (SSF) using wheat straw hydrolysate and Clostridium beijerinckii BA101. Water pretreatment was applied to separate lignin and polysaccharides from the wheat straw. Physical pretreatment was applied prior to water pretreatment where, wheat straw was grounded into fine particles less than 1 mm size. Another experiment was conducted where physical pretreatment was applied alone prior to SSF (i.e. no chemical pretreatment was applied). Both processes converted more than 10% of wheat straw into butanol product. This was 2% higher than previous studies. The results illustrated that SSF with physical pretreatment alone obtained 2.61 g/L butanol.

  12. Comparison of different pretreatment methods for lignocellulosic materials. Part I: conversion of rye straw to valuable products.

    Science.gov (United States)

    Ingram, Thomas; Wörmeyer, Kai; Lima, Juan Carlos Ixcaraguá; Bockemühl, Vera; Antranikian, Garabed; Brunner, Gerd; Smirnova, Irina

    2011-04-01

    The conversion of lignocellulose to valuable products requires I: a fractionation of the major components hemicellulose, cellulose, and lignin, II: an efficient method to process these components to higher valued products. The present work compares liquid hot water (LHW) pretreatment to the soda pulping process and to the ethanol organosolv pretreatment using rye straw as a single lignocellulosic material. The organosolv pretreated rye straw was shown to require the lowest enzyme loading in order to achieve a complete saccharification of cellulose to glucose. At biomass loadings of up to 15% (w/w) cellulose conversion of LHW and organosolv pretreated lignocellulose was found to be almost equal. The soda pulping process shows lower carbohydrate and lignin recoveries compared to the other two processes. In combination with a detailed analysis of the different lignins obtained from the three pretreatment methods, this work gives an overview of the potential products from different pretreatment processes. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Optimization and evaluation of alkaline potassium permanganate pretreatment of corncob.

    Science.gov (United States)

    Ma, Lijuan; Cui, Youzhi; Cai, Rui; Liu, Xueqiang; Zhang, Cuiying; Xiao, Dongguang

    2015-03-01

    Alkaline potassium permanganate solution (APP) was applied to the pretreatment of corncob with a simple and effective optimization of APP concentration, reaction time, temperature and solid to liquid ratio (SLR). The optimized pretreatment conditions were at 2% (w/v) potassium permanganate with SLR of 1:10 treating for 6h at 50°C. This simple one-step treatment resulted in significant 94.56% of the cellulose and 81.47% of the hemicellulose recoveries and 46.79% of the lignin removal of corncob. The reducing sugar in the hydrolysate from APP-pretreated corncob was 8.39g/L after 12h enzymatic hydrolysis, which was 1.44 and 1.29 folds higher than those from raw and acid pretreated corncobs. Physical characteristics, crystallinity and structure of the pretreated corncob were analyzed and assessed by SEM, XRD and FTIR. The APP pretreatment process was novel and enhanced enzymatic hydrolysis of lignocellulose by affecting composition and structural features. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Novel dark fermentation involving bioaugmentation with constructed bacterial consortium for enhanced biohydrogen production from pretreated sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Kotay, Shireen Meher; Das, Debabrata [Department of Biotechnology, Indian Institute of Technology, Kharagpur (India)

    2009-09-15

    The present study summarizes the observations on various nutrient and seed formulation methods using sewage sludge that have been aimed at ameliorating the biohydrogen production potential. Pretreatment methods viz., acid/base treatment, heat treatment, sterilization, freezing-thawing, microwave, ultrasonication and chemical supplementation were attempted on sludge. It was observed that pretreatment was essential not only to reduce the needless, competitive microbial load but also to improve the nutrient solublization of sludge. Heat treatment at 121 C for 20 min was found to be most effective in reducing the microbial load by 98% and hydrolyzing the organic fraction of sludge. However, this pretreatment alone was either not sufficient or inconsistent in developing a suitable microbial consortium for hydrogen production. Hydrogen yield was found to improve 1.5-4 times upon inoculation with H{sub 2}-producing microorganisms. A defined microbial consortium was developed consisting of three established bacteria viz., Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1. Following pretreatments soluble proteins and lipids (the major component of the sludge) were also found to be consumed besides carbohydrates. This laid out the concurrent proteolytic/lipolytic ability of the developed H{sub 2}-producing consortium. 1:1:1 v/v ratio of these bacteria in consortium was found to give the maximum yield of H{sub 2} from sludge, 39.15 ml H{sub 2}/g COD{sub reduced}. 15%v/v dilution and supplementation with 0.5%w/v cane molasses prior to heat treatment was found to further improve the yield to 41.23 ml H{sub 2}/g COD{sub reduced}. (author)

  15. Plasma-Assisted Pretreatment of Wheat Straw for Ethanol Production

    DEFF Research Database (Denmark)

    Schultz-Jensen, Nadja; Kádár, Zsófia; Thomsen, Anne Belinda

    2011-01-01

    (0–7 h), e.g., oxalic acid and acetovanillon. Interestingly, washing had no effect on the ethanol production with pretreatment times up to 1 h. Washing improved the glucose availability with pretreatment times of more than 2 h. One hour of ozonisation was found to be optimal for the use of washed...... carboxylic acids and phenolic compounds were found, e.g., vanillic acid, acetic acid, and formic acid. Some components had the highest concentration at the beginning of the ozonisation process (0.5, 1 h), e.g., 4-hydroxybenzladehyde, while the concentration of others increased during the entire pretreatment...

  16. Spin versus helicity in processes involving transversity

    CERN Document Server

    Mekhfi, Mustapha

    2011-01-01

    We construct the spin formalism in order to deal in a direct and natural way with processes involving transversity which are now of increasing popularity. The helicity formalism which is more appropriate for collision processes of definite helicity has been so far used also to manage processes with transversity, but at the price of computing numerous helicity amplitudes generally involving unnecessary kinematical variables.In a second step we work out the correspondence between both formalisms and retrieve in another way all results of the helicity formalism but in simpler forms.We then compute certain processes for comparison.A special process:the quark dipole magnetic moment is shown to be exclusively treated within the spin formalism as it is directly related to the transverse spin of the quark inside the baryon.

  17. Low intensity surplus activated sludge pretreatment before anaerobic digestion

    Directory of Open Access Journals (Sweden)

    Suschka Jan

    2017-12-01

    Full Text Available Sewage sludge (municipal, or industrial treatment is still a problem in so far that it is not satisfactorily resolved in terms of cost and final disposal. Two common forms of sludge disposal are possible; the first being direct disposal on land (including agriculture and the second being incineration (ash production, although neither of these methods are universally applied. Simplifying the issue, direct sludge disposal on land is seldom applied for sanitary and environmental reasons, while incineration is not popular for financial (high costs reasons. Very often medium and large wastewater treatment plants apply anaerobic digestion for sludge hygiene principles, reducing the amount to be disposed and for biogas (energy production. With the progress in sewage biological treatment aiming at nutrient removal, primary sludge has been omitted in the working processes and only surplus activated sludge requires handling. Anaerobic digestion of waste activated sludge (WAS is more difficult due to the presence of microorganisms, the decomposition of which requires a relatively long time for hydrolysis. In order to upgrade the hydrolysis effects, several different pre-treatment processes have already been developed and introduced. The additional pre-treatment processes applied are aimed at residual sludge bulk mass minimization, shortening of the anaerobic digestion process or higher biogas production, and therefore require additional energy. The water-energy-waste Nexus (treads of of the benefits and operational difficulties, including energy costs are discussed in this paper. The intensity of pre-treatment processes to upgrade the microorganism’s hydrolysis has crucial implications. Here a low intensity pre-treatment process, alkalisation and hydrodynamic disintegration - hybrid process - were presented in order to achieve sufficient effects of WAS anaerobic digestion. A sludge digestion efficiency increase expressed as 45% biogas additional

  18. The chemical properties and microbial community characterization of the thermophilic microaerobic pretreatment process.

    Science.gov (United States)

    Fu, Shan-Fei; He, Shuai; Shi, Xiao-Shuang; Katukuri, Naveen Reddy; Dai, Meng; Guo, Rong-Bo

    2015-12-01

    Thermophilic microaerobic pretreatment (TMP) was recently reported as an efficient pretreatment method of anaerobic digestion (AD). In this study, the chemical properties and microbial community were characterized to reveal how TMP working. Compared with thermophilic treatment under anaerobic condition (TMP0), cellulase activity obviously improved under microaerobic condition (TMP1), which was 10.9-49.0% higher than that of TMP0. Reducing sugar, SCOD and VFAs concentrations of TMP1 were 2.6-8.9%, 1.8-4.8% and 13.8-24% higher than those of TMP0, respectively. TMP gave obvious rise to phylum Firmicutes, which associated with extracellular enzymes production. The proportion of class Bacilli (belongs to phylum Firmicutes and mainly acts during hydrolysis) in TMP1 was 124.89% higher than that of TMP0, which reflected the greater hydrolytic ability under microaerobic condition. The improved abundance of phylum Firmicutes (especially class Bacilli, order Bacillales) under microaerobic condition could be the fundamental reason for the improved AD performance of thermophilic microaerobic pretreated corn straw. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Powerful peracetic acid-ionic liquid pretreatment process for the efficient chemical hydrolysis of lignocellulosic biomass.

    Science.gov (United States)

    Uju; Goto, Masahiro; Kamiya, Noriho

    2016-08-01

    The aim of this work was to design a new method for the efficient saccharification of lignocellulosic biomass (LB) using a combination of peracetic acid (PAA) pretreatment with ionic liquid (IL)-HCl hydrolysis. The pretreatment of LBs with PAA disrupted the lignin fractions, enhanced the dissolution of LB and led to a significant increase in the initial rate of the IL-HCl hydrolysis. The pretreatment of Bagasse with PAA prior to its 1-buthyl-3-methylimidazolium chloride ([Bmim][Cl])-HCl hydrolysis, led to an improvement in the cellulose conversion from 20% to 70% in 1.5h. Interestingly, the 1-buthyl-3-methylpyridium chloride ([Bmpy][Cl])-HCl hydrolysis of Bagasse gave a cellulose conversion greater than 80%, with or without the PAA pretreatment. For LB derived from seaweed waste, the cellulose conversion reached 98% in 1h. The strong hydrolysis power of [Bmpy][Cl] was attributed to its ability to transform cellulose I to II, and lowering the degree of polymerization of cellulose. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Hydrodynamic cavitation as a strategy to enhance the efficiency of lignocellulosic biomass pretreatment.

    Science.gov (United States)

    Terán Hilares, Ruly; Ramos, Lucas; da Silva, Silvio Silvério; Dragone, Giuliano; Mussatto, Solange I; Santos, Júlio César Dos

    2018-06-01

    Hydrodynamic cavitation (HC) is a process technology with potential for application in different areas including environmental, food processing, and biofuels production. Although HC is an undesirable phenomenon for hydraulic equipment, the net energy released during this process is enough to accelerate certain chemical reactions. The application of cavitation energy to enhance the efficiency of lignocellulosic biomass pretreatment is an interesting strategy proposed for integration in biorefineries for the production of bio-based products. Moreover, the use of an HC-assisted process was demonstrated as an attractive alternative when compared to other conventional pretreatment technologies. This is not only due to high pretreatment efficiency resulting in high enzymatic digestibility of carbohydrate fraction, but also, by its high energy efficiency, simple configuration, and construction of systems, besides the possibility of using on the large scale. This paper gives an overview regarding HC technology and its potential for application on the pretreatment of lignocellulosic biomass. The parameters affecting this process and the perspectives for future developments in this area are also presented and discussed.

  1. Advances in paper-based sample pretreatment for point-of-care testing.

    Science.gov (United States)

    Tang, Rui Hua; Yang, Hui; Choi, Jane Ru; Gong, Yan; Feng, Shang Sheng; Pingguan-Murphy, Belinda; Huang, Qing Sheng; Shi, Jun Ling; Mei, Qi Bing; Xu, Feng

    2017-06-01

    In recent years, paper-based point-of-care testing (POCT) has been widely used in medical diagnostics, food safety and environmental monitoring. However, a high-cost, time-consuming and equipment-dependent sample pretreatment technique is generally required for raw sample processing, which are impractical for low-resource and disease-endemic areas. Therefore, there is an escalating demand for a cost-effective, simple and portable pretreatment technique, to be coupled with the commonly used paper-based assay (e.g. lateral flow assay) in POCT. In this review, we focus on the importance of using paper as a platform for sample pretreatment. We firstly discuss the beneficial use of paper for sample pretreatment, including sample collection and storage, separation, extraction, and concentration. We highlight the working principle and fabrication of each sample pretreatment device, the existing challenges and the future perspectives for developing paper-based sample pretreatment technique.

  2. Potential of potassium hydroxide pretreatment of switchgrass for fermentable sugar production.

    Science.gov (United States)

    Sharma, Rajat; Palled, Vijaykumar; Sharma-Shivappa, Ratna R; Osborne, Jason

    2013-02-01

    Chemical pretreatment of lignocellulosic biomass has been extensively investigated for sugar generation and subsequent fuel production. Alkaline pretreatment has emerged as one of the popular chemical pretreatment methods, but most attempts thus far have utilized NaOH for the pretreatment process. This study aimed at investigating the potential of potassium hydroxide (KOH) as a viable alternative alkaline reagent for lignocellulosic pretreatment based on its different reactivity patterns compared to NaOH. Performer switchgrass was pretreated at KOH concentrations of 0.5-2% for varying treatment times of 6-48 h, 6-24 h, and 0.25-1 h at 21, 50, and 121 °C, respectively. The pretreatments resulted in the highest percent sugar retention of 99.26% at 0.5%, 21 °C, 12 h while delignification up to 55.4% was observed with 2% KOH, 121 °C, 1 h. Six pretreatment conditions were selected for subsequent enzymatic hydrolysis with Cellic CTec2® for sugar generation. The pretreatment condition of 0.5% KOH, 24 h, 21 °C was determined to be the most effective as it utilized the least amount of KOH while generating 582.4 mg sugar/g raw biomass for a corresponding percent carbohydrate conversion of 91.8%.

  3. The design of a novel, environmentally improved cotton pre-treatment proces

    NARCIS (Netherlands)

    Bouwhuis, G.H. (Gerrit)

    2011-01-01

    The scope of this thesis of Gerrit Bouwhuis, lecturer at Saxion Research Centre for Design and Technology in Enschede is the development of a new industrial applicable pre-treatment process for cotton based on catalysis. The pre-treatment generally consists of desizing, scouring and bleaching. These

  4. Optimization of electrocoagulation process to treat biologically pretreated bagasse effluent

    Directory of Open Access Journals (Sweden)

    Thirugnanasambandham K.

    2014-01-01

    Full Text Available The main objective of the present study was to investigate the efficiency of electrocoagulation process as a post-treatment to treat biologically pretreated bagasse effluent using iron electrodes. The removal of chemical oxygen demand (COD and total suspended solids (TSS were studied under different operating conditions such as amount of dilution, initial pH, applied current and electrolyte dose by using response surface methodology (RSM coupled with four-factor three-level Box-Behnken experimental design (BBD. The experimental results were analyzed by Pareto analysis of variance (ANOVA and second order polynomial mathematical models were developed with high correlation of efficiency (R2 for COD, TSS removal and electrical energy consumption (EEC. The individual and combined effect of variables on responses was studied using three dimensional response surface plots. Under the optimum operating conditions, such as amount of dilution at 30 %, initial pH of 6.5, applied current of 8 mA cm-2 and electrolyte dose of 740 mg l-1 shows the higher removal efficiency of COD (98 % and TSS (93 % with EEC of 2.40 Wh, which were confirmed by validation experiments.

  5. Pretreatment Engineering Platform Phase 1 Final Test Report

    Energy Technology Data Exchange (ETDEWEB)

    Kurath, Dean E.; Hanson, Brady D.; Minette, Michael J.; Baldwin, David L.; Rapko, Brian M.; Mahoney, Lenna A.; Schonewill, Philip P.; Daniel, Richard C.; Eslinger, Paul W.; Huckaby, James L.; Billing, Justin M.; Sundar, Parameshwaran S.; Josephson, Gary B.; Toth, James J.; Yokuda, Satoru T.; Baer, Ellen BK; Barnes, Steven M.; Golovich, Elizabeth C.; Rassat, Scot D.; Brown, Christopher F.; Geeting, John GH; Sevigny, Gary J.; Casella, Amanda J.; Bontha, Jagannadha R.; Aaberg, Rosanne L.; Aker, Pamela M.; Guzman-Leong, Consuelo E.; Kimura, Marcia L.; Sundaram, S. K.; Pires, Richard P.; Wells, Beric E.; Bredt, Ofelia P.

    2009-12-23

    Pacific Northwest National Laboratory (PNNL) was tasked by Bechtel National Inc. (BNI) on the River Protection Project, Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to conduct testing to demonstrate the performance of the WTP Pretreatment Facility (PTF) leaching and ultrafiltration processes at an engineering-scale. In addition to the demonstration, the testing was to address specific technical issues identified in Issue Response Plan for Implementation of External Flowsheet Review Team (EFRT) Recommendations - M12, Undemonstrated Leaching Processes.( ) Testing was conducted in a 1/4.5-scale mock-up of the PTF ultrafiltration system, the Pretreatment Engineering Platform (PEP). Parallel laboratory testing was conducted in various PNNL laboratories to allow direct comparison of process performance at an engineering-scale and a laboratory-scale. This report presents and discusses the results of those tests.

  6. Pretreatment Engineering Platform Phase 1 Final Test Report

    International Nuclear Information System (INIS)

    Kurath, Dean E.; Hanson, Brady D.; Minette, Michael J.; Baldwin, David L.; Rapko, Brian M.; Mahoney, Lenna A.; Schonewill, Philip P.; Daniel, Richard C.; Eslinger, Paul W.; Huckaby, James L.; Billing, Justin M.; Sundar, Parameshwaran S.; Josephson, Gary B.; Toth, James J.; Yokuda, Satoru T.; Baer, Ellen B.K.; Barnes, Steven M.; Golovich, Elizabeth C.; Rassat, Scot D.; Brown, Christopher F.; Geeting, John G.H.; Sevigny, Gary J.; Casella, Amanda J.; Bontha, Jagannadha R.; Aaberg, Rosanne L.; Aker, Pamela M.; Guzman-Leong, Consuelo E.; Kimura, Marcia L.; Sundaram, S.K.; Pires, Richard P.; Wells, Beric E.; Bredt, Ofelia P.

    2009-01-01

    Pacific Northwest National Laboratory (PNNL) was tasked by Bechtel National Inc. (BNI) on the River Protection Project, Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to conduct testing to demonstrate the performance of the WTP Pretreatment Facility (PTF) leaching and ultrafiltration processes at an engineering-scale. In addition to the demonstration, the testing was to address specific technical issues identified in Issue Response Plan for Implementation of External Flowsheet Review Team (EFRT) Recommendations - M12, Undemonstrated Leaching Processes. Testing was conducted in a 1/4.5-scale mock-up of the PTF ultrafiltration system, the Pretreatment Engineering Platform (PEP). Parallel laboratory testing was conducted in various PNNL laboratories to allow direct comparison of process performance at an engineering-scale and a laboratory-scale. This report presents and discusses the results of those tests.

  7. Ethanol production from SPORL-pretreated lodgepole pine. Preliminary evaluation of mass balance and process energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, J.Y. [USDA Forest Service, Madison, WI (United States). Forest Products Lab.; Wisconsin Univ., Madison, WI (United States). Dept. of Biological Systems Engineering; Zhu, Wenyuan [South China Univ. of Technology, Guangzhou (China). State Key Lab Pulp and Paper Engineering; OBryan, Patricia; Dien, Bruce S. [USDA Agricultural Research Service, Peoria, IL (United States). National Center for Agricultural Utilization Research; Tian, Shen [Capital Normal Univ., Beijing (China). College of Life Science; Gleisner, Rolland [USDA Forest Service, Madison, WI (United States). Forest Products Lab.; Pan, X.J. [Wisconsin Univ., Madison, WI (United States). Dept. of Biological Systems Engineering

    2010-05-15

    Lodgepole pine from forest thinnings is a potential feedstock for ethanol production. In this study, lodgepole pine was converted to ethanol with a yield of 276 L per metric ton of wood or 72% of theoretical yield. The lodgepole pine chips were directly subjected to sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) pretreatment and then disk-milled; the recovered cellulose substrate was quasi-simultaneously saccharified enzymatically and fermented to ethanol using commercial cellulases and Saccharomyces cerevisiae D5A. The liquor stream from the pretreatment containing hydrolyzed sugars mainly from hemicelluloses was fermented by the same yeast strain after detoxification using an XAD resin column. The SPORL pretreatment was conducted at 180 C for a period of 25 min with a liquor-to-wood ratio of 3:1 (v/w) in a laboratory digester. Three levels of sulfuric acid charge (0.0%, 1.4%, and 2.2% on an oven dried wood basis in w/w) and three levels of sodium bisulfite charge (0.0%, 4.0%, and 8.0% in w/w) were applied. Mechanical and thermal energy consumption for milling and pretreatment were determined. These data were used to determine the efficiency of sugar recoveries and net ethanol energy production values and to formulate a preliminary mass and energy balance. (orig.)

  8. Ethanol production from SPORL-pretreated lodgepole pine: preliminary evaluation of mass balance and process energy efficiency.

    Science.gov (United States)

    Zhu, J Y; Zhu, Wenyuan; Obryan, Patricia; Dien, Bruce S; Tian, Shen; Gleisner, Rolland; Pan, X J

    2010-05-01

    Lodgepole pine from forest thinnings is a potential feedstock for ethanol production. In this study, lodgepole pine was converted to ethanol with a yield of 276 L per metric ton of wood or 72% of theoretical yield. The lodgepole pine chips were directly subjected to sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) pretreatment and then disk-milled; the recovered cellulose substrate was quais-simultaneously saccharified enzymatically and fermented to ethanol using commercial cellulases and Saccharomyces cerevisiae D5A. The liquor stream from the pretreatment containing hydrolyzed sugars mainly from hemicelluloses was fermented by the same yeast strain after detoxification using an XAD resin column. The SPORL pretreatment was conducted at 180 degrees C for a period of 25 min with a liquor-to-wood ratio of 3:1 (v/w) in a laboratory digester. Three levels of sulfuric acid charge (0.0%, 1.4%, and 2.2% on an oven dried wood basis in w/w) and three levels of sodium bisulfite charge (0.0%, 4.0%, and 8.0% in w/w) were applied. Mechanical and thermal energy consumption for milling and pretreatment were determined. These data were used to determine the efficiency of sugar recoveries and net ethanol energy production values and to formulate a preliminary mass and energy balance.

  9. Organic solvent pretreatment of lignocellulosic biomass for biofuels and biochemicals: A review.

    Science.gov (United States)

    Zhang, Ke; Pei, Zhijian; Wang, Donghai

    2016-01-01

    Lignocellulosic biomass represents the largest potential volume and lowest cost for biofuel and biochemical production. Pretreatment is an essential component of biomass conversion process, affecting a majority of downstream processes, including enzymatic hydrolysis, fermentation, and final product separation. Organic solvent pretreatment is recognized as an emerging way ahead because of its inherent advantages, such as the ability to fractionate lignocellulosic biomass into cellulose, lignin, and hemicellulose components with high purity, as well as easy solvent recovery and solvent reuse. Objectives of this review were to update and extend previous works on pretreatment of lignocellulosic biomass for biofuels and biochemicals using organic solvents, especially on ethanol, methanol, ethylene glycol, glycerol, acetic acid, and formic acid. Perspectives and recommendations were given to fully describe implementation of proper organic solvent pretreatment for future research. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Effect of cadmium pretreatment on liver regeneration after partial hepatectomy in rats

    International Nuclear Information System (INIS)

    Margeli, A.; Theocharis, S.; Skaltsas, S.; Skopelitou, A.; Kittas, C.; Mykoniatis, M.; Varonos, D.

    1994-01-01

    In this study we examined the effect of cadmium pretreatment, administered 24 h before partial hepatectomy, on the liver regenerative process in rats, at different time intervals. The rate of 3 H thymidine incorporation into hepatic DNA and the activity of the enzyme thymidine kinase were used as indices of liver proliferative capacity. Thymidine kinase, the rate-determining enzyme of DNA biosynthesis, was suppressed during the first hours following partial hepatectomy in the liver of cadmium pretreated animals. DNA biosynthesis was also strongly decreased in cadmium pretreated animals, by delaying the first peak of liver regeneration, compared with the partially hepatectomized ones. Biochemical parameters, mitotic index and proliferating cell nuclear antigen staining were also coestimated. The above data suggest that cadmium pretreatment suppressed the hepatic regenerative process, probably due to the inhibition of thymidine kinase. (orig./MG)

  11. Autohydrolysis pretreatment assessment in ethanol production from agave bagasse.

    Science.gov (United States)

    Rios-González, Leopoldo J; Morales-Martínez, Thelma K; Rodríguez-Flores, María F; Rodríguez-De la Garza, José A; Castillo-Quiroz, David; Castro-Montoya, Agustín J; Martinez, Alfredo

    2017-10-01

    The aim of the present work was to assess the autohydrolysis pretreatment of Agave tequilana bagasse for ethanol production. The pretreatment was conducted using a one-liter high pressure Parr reactor under different severity factors (SF) at a 1:6w/v ratio (solid:liquid) and 200rpm. The solids obtained under the selected autohydrolysis conditions were subjected to enzymatic hydrolysis with a commercial cellulase cocktail, and the enzymatic hydrolysate was fermented using Saccharomyces cerevisiae. The results obtained from the pretreatment process showed that the glucan content in the pretreated solid was mostly preserved, and an increase in the digestibility was observed for the case with a SF of 4.13 (190°C, 30min). Enzymatic hydrolysis of the pretreated solids showed a yield of 74.3%, with a glucose concentration of 126g/L, resulting in 65.26g/L of ethanol after 10h of fermentation, which represent a 98.4% conversion according to the theoretical ethanol yield value. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Pretreatment and preheating of scrap. Tarkastelu koskien romun esikaesittely- ja esikuumennusmenetelmiae

    Energy Technology Data Exchange (ETDEWEB)

    Hooli, P.; Hanni, J. (Outokumpu Oy Tornion Tehtaat, Tornio (Finland))

    1990-01-01

    As a background for this study has been those demands for scrap treatments and transportation, which are coming with increasing production of melting shop of Outokumpu Oy's Tornio works and also problems caused by snow among productionrate. Different pretreatment-, transport-, and preheatingmethods and some alternatives has been studied to arrange those as a functioning complete. Also very exact plannings for some pretreatmentmethods has been made. From preheatingmethods some methods, which are concerned to be effective and possible in the future has been studied. In addition those parameters, which are involved to the effectivity of preheating process in melting shop of Outokumpu Oy's Tornio works has been examined.

  13. Pretreatment and preheating of scrap; Tarkastelu koskien romun esikaesittely- ja esikuumennusmenetelmiae

    Energy Technology Data Exchange (ETDEWEB)

    Hooli, P.; Hanni, J. [Outokumpu Oy Tornion Tehtaat, Tornio (Finland)

    1990-12-31

    As a background for this study has been those demands for scrap treatments and transportation, which are coming with increasing production of melting shop of Outokumpu Oy`s Tornio works and also problems caused by snow among productionrate. Different pretreatment-, transport-, and preheatingmethods and some alternatives has been studied to arrange those as a functioning complete. Also very exact plannings for some pretreatmentmethods has been made. From preheatingmethods some methods, which are concerned to be effective and possible in the future has been studied. In addition those parameters, which are involved to the effectivity of preheating process in melting shop of Outokumpu Oy`s Tornio works has been examined.

  14. Optimization of Alkaline and Dilute Acid Pretreatment of Agave Bagasse by Response Surface Methodology

    Science.gov (United States)

    Ávila-Lara, Abimael I.; Camberos-Flores, Jesus N.; Mendoza-Pérez, Jorge A.; Messina-Fernández, Sarah R.; Saldaña-Duran, Claudia E.; Jimenez-Ruiz, Edgar I.; Sánchez-Herrera, Leticia M.; Pérez-Pimienta, Jose A.

    2015-01-01

    Utilization of lignocellulosic materials for the production of value-added chemicals or biofuels generally requires a pretreatment process to overcome the recalcitrance of the plant biomass for further enzymatic hydrolysis and fermentation stages. Two of the most employed pretreatment processes are the ones that used dilute acid (DA) and alkaline (AL) catalyst providing specific effects on the physicochemical structure of the biomass, such as high xylan and lignin removal for DA and AL, respectively. Another important effect that need to be studied is the use of a high solids pretreatment (≥15%) since offers many advantaged over lower solids loadings, including increased sugar and ethanol concentrations (in combination with a high solids saccharification), which will be reflected in lower capital costs; however, this data is currently limited. In this study, several variables, such as catalyst loading, retention time, and solids loading, were studied using response surface methodology (RSM) based on a factorial central composite design of DA and AL pretreatment on agave bagasse using a range of solids from 3 to 30% (w/w) to obtain optimal process conditions for each pretreatment. Subsequently enzymatic hydrolysis was performed using Novozymes Cellic CTec2 and HTec2 presented as total reducing sugar (TRS) yield. Pretreated biomass was characterized by wet-chemistry techniques and selected samples were analyzed by calorimetric techniques, and scanning electron/confocal fluorescent microscopy. RSM was also used to optimize the pretreatment conditions for maximum TRS yield. The optimum conditions were determined for AL pretreatment: 1.87% NaOH concentration, 50.3 min and 13.1% solids loading, whereas DA pretreatment: 2.1% acid concentration, 33.8 min and 8.5% solids loading. PMID:26442260

  15. Methods for pretreating biomass

    Science.gov (United States)

    Balan, Venkatesh; Dale, Bruce E; Chundawat, Shishir; Sousa, Leonardo

    2017-05-09

    A method for pretreating biomass is provided, which includes, in a reactor, allowing gaseous ammonia to condense on the biomass and react with water present in the biomass to produce pretreated biomass, wherein reactivity of polysaccharides in the biomass is increased during subsequent biological conversion as compared to the reactivity of polysaccharides in biomass which has not been pretreated. A method for pretreating biomass with a liquid ammonia and recovering the liquid ammonia is also provided. Related systems which include a biochemical or biofuel production facility are also disclosed.

  16. Microbial pretreatment of cotton stalks by Phanerochaete chrysosporium for bioethanol production

    Science.gov (United States)

    Shi, Jian

    Lignocellulosic biomass has been recognized as a widespread, potentially low cost renewable source of mixed sugars for fermentation to fuel ethanol. Pretreatment, as the first step towards conversion of lignocellulose to ethanol, remains one of the main barriers to technical and commercial success of the processing technology. Existing pretreatment methods have largely been developed on the basis of physiochemical technologies which are considered relatively expensive and usually involve adverse environmental impacts. In this study, an environmentally benign alternative, microbial pretreatment using Phanerochaete chrysosporium, was explored to degrade lignin in cotton stalks and facilitate their conversion into ethanol. Two submerged liquid pretreatment techniques (SmC), shallow stationary and agitated cultivation, at three inorganic salt concentrations (no salts, modified salts without Mn2+, modified salts with Mn2+) were compared by evaluating their pretreatment efficiencies. Shallow stationary cultivation with no salt was superior to other pretreatment conditions and gave 20.7% lignin degradation along with 76.3% solids recovery and 29.0% carbohydrate availability over a 14 day period. The influence of substrate moisture content (65%, 75% and 80% M.C. wet-basis), inorganic salt concentration (no salts, modified salts without Mn2+ , modified salts with Mn2+) and culture time (0-14 days) on pretreatment effectiveness in solid state (SSC) systems was also examined. It was shown that solid state cultivation at 75% M.C. without salts was the most preferable pretreatment resulting in 27.6% lignin degradation, 71.1% solids recovery and 41.6% carbohydrate availability over a period of 14 days. A study on hydrolysis and fermentation of cotton stalks treated microbially using the most promising SmC (shallow stationary, no salts) and SSC (75% moisture content, no salts) methods resulted in no increase in cellulose conversion with direct enzyme application (10.98% and 3

  17. Effect of Different Sugar Beet Pulp Pretreatments on Biogas Production Efficiency.

    Science.gov (United States)

    Ziemiński, Krzysztof; Kowalska-Wentel, Monika

    2017-03-01

    The objective of this study was to determine the effect of different sugar beet pulp (SBP) pretreatments on biogas yield from anaerobic digestion. SBP was subjected to grinding, thermal-pressure processing, enzymatic hydrolysis, or combination of these pretreatments. It was observed that grinding of SBP to 2.5-mm particles resulted in the cumulative biogas productivity of 617.2 mL/g volatile solids (VS), which was 20.2 % higher compared to the biogas yield from the not pretreated SBP, and comparable to that from not ground, enzymatically hydrolyzed SBP. The highest cumulative biogas productivity, 898.7 mL/g VS, was obtained from the ground, thermal-pressure pretreated and enzymatically hydrolyzed SBP. The latter pretreatment variant enabled to achieve the highest glucose concentration (24.765 mg/mL) in the enzymatic hydrolysates. The analysis of energy balance showed that the increase in the number of SBP pretreatment operations significantly reduced the gain of electric energy.

  18. Improving the sludge disintegration efficiency of sonication by combining with alkalization and thermal pre-treatment methods.

    Science.gov (United States)

    Şahinkaya, S; Sevimli, M F; Aygün, A

    2012-01-01

    One of the most serious problems encountered in biological wastewater treatment processes is the production of waste activated sludge (WAS). Sonication, which is an energy-intensive process, is the most powerful sludge pre-treatment method. Due to lack of information about the combined pre-treatment methods of sonication, the combined pre-treatment methods were investigated and it was aimed to improve the disintegration efficiency of sonication by combining sonication with alkalization and thermal pre-treatment methods in this study. The process performances were evaluated based on the quantities of increases in soluble chemical oxygen demand (COD), protein and carbohydrate. The releases of soluble COD, carbohydrate and protein by the combined methods were higher than those by sonication, alkalization and thermal pre-treatment alone. Degrees of sludge disintegration in various options of sonication were in the following descending order: sono-alkalization > sono-thermal pre-treatment > sonication. Therefore, it was determined that combining sonication with alkalization significantly improved the sludge disintegration and decreased the required energy to reach the same yield by sonication. In addition, effects on sludge settleability and dewaterability and kinetic mathematical modelling of pre-treatment performances of these methods were investigated. It was proven that the proposed model accurately predicted the efficiencies of ultrasonic pre-treatment methods.

  19. Pretreatment and processing of field biomasses for production of precious, bulk and energy fiber fractions; Peltobiomassojen esikaesittely ja prosessointi arvo-, bulkki- ja energiakuitujakeiden tuottamiseksi

    Energy Technology Data Exchange (ETDEWEB)

    Vilppunen, P.; Sohlo, J. [Oulu Univ., Oulu (Finland). Dept. of Process Engineering

    1995-12-31

    The objective of the research was to make a preliminary study on pretreatment and processing possibilities of different field biomasses for production of specific product fractions with dry and wet separation methods. Pretreatment processes and possible combinations, before pulping and energy production, were studied in the dry-fraction part of the research. Sieving technology, air-classifier and a collision separator were tested. Additionally, the fuel processing systems of present power/thermal plants were studied in practice. A new type of separation system, based on removal of fines with collision-separator, was designed in the sub-project. The results of the sub-project are now utilized in other researches of the Bioenergy Research Programme. Separation processes for energy and fiber fractions, predominantly those for seed flax, using traditional pulp classifiers and the new pressure classifier process were studied in the wet-separation part of the project. A combined plant fiber further-refining process, based on mechanical and biotechnical separation, operating on the basis of fiber length, was developed on the basis of dry and wet frection tests

  20. Pretreatment and processing of field biomasses for production of precious, bulk and energy fiber fractions; Peltobiomassojen esikaesittely ja prosessointi arvo-, bulkki- ja energiakuitujakeiden tuottamiseksi

    Energy Technology Data Exchange (ETDEWEB)

    Vilppunen, P; Sohlo, J [Oulu Univ., Oulu (Finland). Dept. of Process Engineering

    1996-12-31

    The objective of the research was to make a preliminary study on pretreatment and processing possibilities of different field biomasses for production of specific product fractions with dry and wet separation methods. Pretreatment processes and possible combinations, before pulping and energy production, were studied in the dry-fraction part of the research. Sieving technology, air-classifier and a collision separator were tested. Additionally, the fuel processing systems of present power/thermal plants were studied in practice. A new type of separation system, based on removal of fines with collision-separator, was designed in the sub-project. The results of the sub-project are now utilized in other researches of the Bioenergy Research Programme. Separation processes for energy and fiber fractions, predominantly those for seed flax, using traditional pulp classifiers and the new pressure classifier process were studied in the wet-separation part of the project. A combined plant fiber further-refining process, based on mechanical and biotechnical separation, operating on the basis of fiber length, was developed on the basis of dry and wet frection tests

  1. Bioethanol production from paperboard mill sludge using acid-catalyzed bio-derived choline acetate ionic liquid pretreatment followed by fermentation process

    International Nuclear Information System (INIS)

    Farghaly, Ahmed; Elsamadony, Mohamed; Ookawara, Shinichi; Tawfik, Ahmed

    2017-01-01

    Highlights: • Total reducing sugar concentration depends on [ChO][OAc] ionic liquid to biomass ratio. • Acid-catalyzed ionic liquid significantly enhance pretreatment process. • Prolonged pretreatment duration degraded sugars into furans compounds. • Maximum net energy of 5.36 ± 0.30 kJ/g PMS obtained by using acid catalyst IL. - Abstract: Paperboard mill sludge (PMS) composed of cellulose, hemicellulose, lignin and ash contents of 36.72 ± 2.81, 32.91 ± 1.75, 22.89 ± 0.56, and 7.48 ± 0.39%, respectively. Enzymatic hydrolysis process followed by fermentation of native PMS provided an ethanol yield of 0.36 ± 0.01 g/L which equivalent to net gain energy of −0.84 ± 0.03 kJ/g PMS . Choline acetate ionic liquid [Cho][OAc] IL was extensively used as a solvent for PMS to upgrade the performance. Pretreatment with [Cho][OAc] IL/PMS ratio of 10% (w/w) for 1.0 h, at a temperature of 120 °C exhibited hemicellulose and lignin removal efficiency of 5.05 ± 0.52 and 14.71 ± 1.22%, respectively with 89.19 ± 5.62% cellulose recovery. This corresponded to net gain energy of 0.60 ± 0.04 kJ/g PMS based on ethanol yield from enzymatic saccharification process which was quite low due to a limited hemicellulose removal and glucose yield of 24.1 ± 1.4 g/L. [Cho][OAc] IL/PMS ratio of 10% (w/w) supplemented with 1% (v/v) HCl substantially improved the removal efficiency of hemicellulose (36.38 ± 4.51%), lignin (17.42 ± 1.19%) and cellulose (82.17 ± 4.28%) which provided the maximum net energy of 5.36 ± 0.30 kJ/g PMS .

  2. Study of Enzymatic Hydrolysis of Dilute Acid Pretreated Coconut Husk

    Directory of Open Access Journals (Sweden)

    Rudy Agustriyanto

    2012-12-01

    Full Text Available Coconut husk is classified as complex lignocellulosic material that contains cellulose, hemicellulose, lignin, and some other extractive compounds. Cellulose from coconut husk can be used as fermentation substrate after enzymatic hydrolysis. In contrary, lignin content from the coconut husk will act as an inhibitor in this hydrolysis process. Therefore, a pretreatment process is needed to enhance the hydrolysis of cellulose. The objective of this research is to investigate the production of the glucose through dilute acid pretreatment and to obtain its optimum operating conditions. In this study, the pretreatment was done using dilute sulfuric acid in an autoclave reactor. The pretreatment condition were varied at 80°C, 100°C, 120°C and 0.9%, 1.2%, 1.5% for temperature and acid concentration respectively. The acid pretreated coconut husk was then hydrolyzed using commercial cellulase (celluclast and β-glucosidase (Novozyme 188. The hydrolysis time was 72 hours and the operating conditions were varied at several temperature and pH. From the experimental results it can be concluded that the delignification temperature variation has greater influence than the acid concentration. The optimum operating condition was obtained at pH 4 and 50°C which was pretreated at 100°C using 1.5% acid concentration. Copyright © 2012 by BCREC UNDIP. All rights reserved. (Selected Paper from International Conference on Chemical and Material Engineering (ICCME 2012Received: 28th September 2012, Revised: 2nd October 2012, Accepted: 4th October 2012[How to Cite: R. Agustriyanto, A. Fatmawati, Y. Liasari. (2012. Study of Enzymatic Hydrolysis of Dilute Acid Pretreated Coconut Husk. Bulletin of Chemical Reaction Engineering & Catalysis, 7(2: 137-141. doi:10.9767/bcrec.7.2.4046.137-141] [How to Link / DOI: http://dx.doi.org/10.9767/bcrec.7.2.4046.137-141 ] | View in 

  3. Use of agave bagasse for production of an organic fertilizer by pretreatment with Bjerkandera adusta and vermicomposting with Eisenia fetida.

    Science.gov (United States)

    Moran-Salazar, Rene G; Marino-Marmolejo, Erika N; Rodriguez-Campos, Jacobo; Davila-Vazquez, Gustavo; Contreras-Ramos, Silvia M

    2016-01-01

    Agave tequilana Weber is used in tequila and fructans production, with agave bagasse generated as a solid waste. The main use of bagasse is to produce compost in tequila factories with a long traditional composting that lasts 6-8 months. The aim of this study was to evaluate the degradation of agave bagasse by combining a pretreatment with fungi and vermicomposting. Experiments were carried out with fractionated or whole bagasse, sterilized or not, subjecting it to a pretreatment with Bjerkandera adusta alone or combined with native fungi, or only with native bagasse fungi (non-sterilized), for 45 days. This was followed by a vermicomposting with Eisenia fetida and sewage sludge, for another 45 days. Physicochemical parameters, lignocellulose degradation, stability and maturity changes were measured. The results indicated that up to 90% of the residual sugars in bagasse were eliminated after 30 days in all treatments. The highest degradation rate in pretreatment was observed in non-sterilized, fractionated bagasse with native fungi plus B. adusta (BNFns) (71% hemicellulose, 43% cellulose and 71% lignin) at 45 days. The highest total degradation rates after vermicomposting were in fractionated bagasse pre-treated with native fungi (94% hemicellulose, 86% cellulose and 91% lignin). However, the treatment BNFns showed better maturity and stability parameters compared to that reported for traditional composts. Thus, it seems that a process involving vermicomposting and pretreatment with B. adusta could reduce the degradation time of bagasse to 3 months, compared to the traditional composting process, which requires from 6 to 8 months.

  4. Does residual H2O2 result in inhibitory effect on enhanced anaerobic digestion of sludge pretreated by microwave-H2O2 pretreatment process?

    Science.gov (United States)

    Liu, Jibao; Jia, Ruilai; Wang, Yawei; Wei, Yuansong; Zhang, Junya; Wang, Rui; Cai, Xing

    2017-04-01

    This study investigated the effects of residual H 2 O 2 on hydrolysis-acidification and methanogenesis stages of anaerobic digestion after microwave-H 2 O 2 (MW-H 2 O 2 ) pretreatment of waste activated sludge (WAS). Results showed that high sludge solubilization at 35-45 % was achieved after pretreatment, while large amounts of residual H 2 O 2 remained and refractory compounds were thus generated with high dosage of H 2 O 2 (0.6 g H 2 O 2 /g total solids (TS), 1.0 g H 2 O 2 /g TS) pretreatment. The residual H 2 O 2 not only inhibited hydrolysis-acidification stage mildly, such as hydrolase activity, but also had acute toxic effect on methanogens, resulting in long lag phase, low methane yield rate, and no increase of cumulative methane production during the 30-day BMP tests. When the low dosage of H 2 O 2 at 0.2 g H 2 O 2 /g TS was used in MW-H 2 O 2 pretreatment, sludge anaerobic digestion was significantly enhanced. The cumulative methane production increased by 29.02 %, but still with a lag phase of 1.0 day. With removing the residual H 2 O 2 by catalase, the initial lag phase of hydrolysis-acidification stage decreased from 1.0 to 0.5 day.

  5. Effect of alkaline microwaving pretreatment on anaerobic digestion and biogas production of swine manure

    OpenAIRE

    Tao Yu; Yihuan Deng; Hongyu Liu; Chunping Yang; Bingwen Wu; Guangming Zeng; Li Lu; Fumitake Nishimura

    2017-01-01

    Microwave assisted with alkaline (MW-A) condition was applied in the pretreatment of swine manure, and the effect of the pretreatment on anaerobic treatment and biogas production was evaluated in this study. The two main microwaving (MW) parameters, microwaving power and reaction time, were optimized for the pretreatment. Response surface methodology (RSM) was used to investigate the effect of alkaline microwaving process for manure pretreatment at various values of pH and energy input. Resul...

  6. Pretreatment Process for performance Improvement of SIES at Kori Unit 2 in Korea

    International Nuclear Information System (INIS)

    Lee, Sang Jin; Yang, Ho Yeon; Shin, Sang Woon; Song, Myung Jae

    1994-01-01

    Pretreatment process consisted of submerged hollow-fiber microfiltration(HMF) membrane and spiral-wound nanofiltration(SNF) membrane has been developed by NETEC, KHNP for the purpose of improving the impurities of liquid radioactive waste before entering Selective Ion Exchange System(SIES). The lab-scale combined system was installed at Kori NPP no. 2 nuclear power plant and demonstration tests using actual liquid radioactive waste were carried out to verify the performance of the combined system. The submerged HMF membrane was adopted for removal of suspended solid in liquid radioactive waste and the SNF membrane was used for removal of particulate radioisotope such as, Ag-110m and oily waste because ion exchange resin can not remove particulate radioisotopes. The liquid waste in Waste Holdup Tank(WHT) was processed with HMF and SNF membrane, and SIES. The initial SS concentration and total activity of actual waste were 38,000ppb and 1.534x10 -3 μCi/cc, respectively. The SS concentration and total activity of permeate were 30ppb and lower than LLD(Lower Limit of Detection), respectively

  7. Innovative UVC light (185 nm) and radio-frequency-plasma pretreatment of Nylon surfaces at atmospheric pressure and their implications in photocatalytic processes.

    Science.gov (United States)

    Mejía, M I; Marín, J M; Restrepo, G; Pulgarín, C; Mielczarski, E; Mielczarski, J; Stolitchnov, I; Kiwi, J

    2009-10-01

    Innovative pretreatment by UVC light (185 nm) and by radio-frequency (RF) plasma at atmospheric pressure to functionalize the Nylon surface, increasing its bondability toward TiO(2), is reported in this study. In the case of UVC light pretreatment in air, the molar absorption coefficient of O(2)/N(2) at 185 nm is very low and the air in the chamber absorbs very little light from the UVC source before reaching the Nylon sample. Nylon fabrics under RF plasma were also functionalized at atmospheric pressure because of the marked heating effect introduced in the Nylon by the RF plasma. This effect leads to intermolecular bond breaking and oxygenated surface groups in the topmost Nylon layers. Both pretreatments enhanced significantly the photocatalytic discoloration of the red-wine stain in Nylon-TiO(2) compared with samples without pretreatment. The UVC and RF methods in the absence of vacuum imply a considerable cost reduction to functionalize textile surfaces, suggesting a potential industrial application. Red-wine-stain discoloration under simulated sunlight was monitored quantitatively by diffuse-reflectance spectroscopy and by CO(2) evolution. X-ray photoelectron spectroscopy (XPS) was used to monitor the changes of the C, N, and S species on the Nylon topmost layers during the discoloration process. Significant changes in the XPS spectra of Ti 2p peaks were observed during discoloration of the wine spots. Wine stains attenuated the signal of the Ti 2p (458.4 eV) peak in the Nylon-TiO(2)-stained wine sample at time zero (from now on, the time before the discoloration process). Furthermore, a decrease of the wine-related O 1s signal at 529.7 eV and N 1s signal at 399.5 eV was observed during the discoloration process, indicating an efficient catalytic decomposition of the wine pigment on Nylon-TiO(2). X-ray diffraction detected the formation of anatase on the Nylon fibers. High-resolution transmission electron microscopy shows the formation of anatase particles

  8. Effect of iron salt type and dosing mode on Fenton-based pretreatment of rice straw for enzymatic hydrolysis.

    Science.gov (United States)

    Gan, Yu-Yan; Zhou, Si-Li; Dai, Xiao; Wu, Han; Xiong, Zi-Yao; Qin, Yuan-Hang; Ma, Jiayu; Yang, Li; Wu, Zai-Kun; Wang, Tie-Lin; Wang, Wei-Guo; Wang, Cun-Wen

    2018-06-15

    Fenton-based processes with four different iron salts in two different dosing modes were used to pretreat rice straw (RS) samples to increase their enzymatic digestibility. The composition analysis shows that the RS sample pretreated by the dosing mode of iron salt adding into H 2 O 2 has a much lower hemicellulose content than that pretreated by the dosing mode of H 2 O 2 adding into iron salt, and the RS sample pretreated by the chloride salt-based Fenton process has a much lower lignin content and a slightly lower hemicellulose content than that pretreated by the sulphate salt-based Fenton process. The higher concentration of reducing sugar observed on the RS sample with lower lignin and hemicellulose contents justifies that the Fenton-based process could enhance the enzymic hydrolysis of RS by removing hemicellulose and lignin and increasing its accessibility to cellulase. FeCl 3 ·6H 2 O adding into H 2 O 2 is the most efficient Fenton-based process for RS pretreatment. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Effects of process parameters of various pretreatments on enzymatic hydrolysability of Ceiba pentandra (L.) Gaertn. (Kapok) fibre: A response surface methodology study

    International Nuclear Information System (INIS)

    Tye, Ying Ying; Lee, Keat Teong; Wan Abdullah, Wan Nadiah; Leh, Cheu Peng

    2015-01-01

    Kapok fibre is a promising raw material to produce sugar by enzymatic hydrolysis. In this work, effects of water, acid and alkaline pretreatments on the enzymatic sugar yield were studied through response surface methodology (RSM) and supported by the analysis of chemical compositions and physical structure of the fibre. For water pretreatment, reaction temperature and time were the independent variables while chemical concentration was also used as the third independent variable for acid and alkaline pretreatments. For all pretreatments, the enzymatic hydrolysis conditions were kept constant. The structure of pretreated fibre was also examined using scanning electron microscope (SEM). Results showed that water and acid pretreatments effectively dissolved hemicellulose of the fibre with the latter unveiled better results. The alkaline pretreatment resulted in the highest total glucose yield (g/kg of untreated fibre) as compared to water and acid pretreatments. SEM analysis illustrated that water and acid pretreatments led severe destruction of fibre structure; however, both of these pretreatments exhibited lower enhancement of enzymatic hydrolysability of kapok fibre as compared to that observed in alkaline pretreatment. - Highlights: • Effect of pretreatments on sugar yield was studied by response surface methodology. • Glucose yield was highly related to the chemical compositions of pretreated fibers. • Pretreatments altered the physical structure of kapok fibers. • Enzymatic hydrolysability of fibre was improved the most by alkaline treatment. • Over 94% cellulose of the pretreated fibres was converted to glucose

  10. Optimization of alkaline and dilute acid pretreatment of agave bagasse by response surface methodology

    Directory of Open Access Journals (Sweden)

    Abimael I. Ávila-Lara

    2015-09-01

    Full Text Available Utilization of lignocellulosic materials for the production of value-added chemicals or biofuels generally requires a pretreatment process to overcome the recalcitrance of the plant biomass for further enzymatic hydrolysis and fermentation stages. Two of the most employed pretreatment processes are the ones that used dilute acid (DA and alkaline (AL catalyst providing specific effects on the physicochemical structure of the biomass such as high xylan and lignin removal for DA and AL, respectively. Another important effect that need to be studied is the use of a high solids pretreatment (≥15% since offers many advantaged over lower solids loadings, including increased sugar and ethanol concentrations (in combination with a high solids saccharification which will be reflected in lower capital costs, however this data is currently limited. In this study, several variables such as catalyst loading, retention time and solids loading, were studied using Response Surface Methodology (RSM based on a factorial Central Composite Design (CCD of DA and AL pretreatment on agave bagasse using a range of solids from 3 to 30% (w/w to obtain optimal process conditions for each pretreatment. Subsequently enzymatic hydrolysis was performed using Novozymes Cellic CTec2 and HTec2 presented as total reducing sugar (TRS yield. Pretreated biomass

  11. Enzymatic hydrolysis of pretreated barley and wheat straw

    DEFF Research Database (Denmark)

    Rosgaard, Lisa

    2007-01-01

    . The work involved evaluation of 1) possible ways to increase the glucose release from the commercial cellulase product Celluclast by boosting with other enzyme activities to increase the enzymatic hydrolysis, 2) comparing differently pretreated feedstock substrates and 3) evaluating a fed-batch substrate...... mixture resulted in a glucose release corresponding to ~84 % of the glucose release from Celluclast. It was therefore suggested that other enzyme activities than the 4 four main cellulase activities in Celluclast are necessary for optimal hydrolysis of lignocellulose. Even though Celluclast...... is a multicomponent cellulase mixture, there are still possibilities for further improvement in terms of providing the most efficient cellulase mixture for lignocellulose hydrolysis. It was shown that substrates evaluated all had some residual hemicellulose in the solid cellulose fraction after pretreatment...

  12. Methods for producing and using densified biomass products containing pretreated biomass fibers

    Science.gov (United States)

    Dale, Bruce E.; Ritchie, Bryan; Marshall, Derek

    2015-05-26

    A process is provided comprising subjecting a quantity of plant biomass fibers to a pretreatment to cause at least a portion of lignin contained within each fiber to move to an outer surface of said fiber, wherein a quantity of pretreated tacky plant biomass fibers is produced; and densifying the quantity of pretreated tacky plant biomass fibers to produce one or more densified biomass particulates, wherein said biomass fibers are densified without using added binder.

  13. Hydrodynamic cavitation as a strategy to enhance the efficiency of lignocellulosic biomass pretreatment

    DEFF Research Database (Denmark)

    Terán Hilares, Ruly; Ramos, Lucas; da Silva, Silvio Silvério

    2018-01-01

    to accelerate certain chemical reactions. The application of cavitation energy to enhance the efficiency of lignocellulosic biomass pretreatment is an interesting strategy proposed for integration in biorefineries for the production of bio-based products. Moreover, the use of an HC-assisted process...... was demonstrated as an attractive alternative when compared to other conventional pretreatment technologies. This is not only due to high pretreatment efficiency resulting in high enzymatic digestibility of carbohydrate fraction, but also, by its high energy efficiency, simple configuration, and construction...... of systems, besides the possibility of using on the large scale. This paper gives an overview regarding HC technology and its potential for application on the pretreatment of lignocellulosic biomass. The parameters affecting this process and the perspectives for future developments in this area are also...

  14. Soaking assisted thermal pretreatment of cassava peels wastes for fermentable sugar production: Process modelling and optimization

    International Nuclear Information System (INIS)

    Aruwajoye, Gabriel S.; Faloye, Funmilayo D.; Kana, Evariste Gueguim

    2017-01-01

    Highlights: • Soaking Assisted Thermal Pretreatment (SATP) of Cassava Peels’ waste is reported. • Maximum fermentable sugar of 0.93 g/g and 90.90% sugar recovery was achieved. • This technique gave a 31% sugar yield improvement over enzymatic pretreatment. • SEM and FTIR analysis confirms the efficiency of SATP. - Abstract: This study reports a hybrid pretreatment strategy for optimum fermentable sugar (FS) release from cassava peels waste. The Response Surface design method was used to investigate the effect of soaking temperature, soaking duration, autoclave duration, acid concentration and solid loading on reducing sugar yield. The model gave a coefficient of determination (R 2 ) of 0.87. The optimum pretreatment conditions of 69.62 °C soaking temperature, 2.57 h soaking duration, 5 min autoclave duration, 3.68 v/v acid concentration and 9.65% w/v solid loading were obtained. Maximum reducing sugar of 89.80 ± 2.87 g/L corresponding to a fermentable sugar yield of 0.93 ± 0.03 g/g cassava peels was achieved upon model validation. A percentage sugar recovery of 90.79% was achieved with a 31% improvement in the FS yield from the enzyme pretreatment. The combined severity factor (CSF) of 0.77 and the low concentration of inhibitory compounds achieved further demonstrates the efficiency of this technique.

  15. Simultaneous saccharification and co-fermentation of peracetic acid pretreated sugar cane bagasse

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, L.C. [Fundacao Centro Tecnologico de Minas Gerais, Belo Horizonte (Brazil); Linden, J.C.; Schroeder, H.A. [Colorado State University, Fort Collins, CO (United States)

    1999-07-01

    Previous work in our laboratory has demonstrated that peracetic acid improves the enzymatic digestibility of lignocellulosic materials. From the same studies, use of dilute alkali solutions as a pre-pretreatment prior to peracetic acid lignin oxidation increases sugar conversion yields in a synergistic, not additive, manner. Deacetylation of xylan is conducted easily by use of dilute alkali solutions at mild conditions. In this paper, the effectiveness of peracetic acid pretreatment of sugar cane bagasse combined with an alkaline pre-pretreatment, is evaluated through simultaneous saccharification and co-fermentation (SSCF) procedures. A practical 92% of theoretical ethanol yield using recombinant Zymomonas mobilis CP4/pZB5 is achieved using 6% NaOH/I5% peracetic acid pretreated substrate. No sugar accumulation is observed during SSCF; the recombinant microorganism exhibits greater glucose utilization rates than those of xylose. Acetate levels at the end of the co-fermentations are less than 0.2% (w/v). Based on demonstrated reduction of acetyl groups of the biomass, alkaline pre-pretreatments help to reduce peracetic acid requirements. The influence of deacetylation is more pronounced in combined pretreatments using lower peracetic acid loadings. Stereochemical impediments of the acetyl groups in hemicellulase on the activity of specific enzymes may be involved. (author)

  16. Electroacupuncture pretreatment induces tolerance against focal cerebral ischemia through activation of canonical Notch pathway

    Directory of Open Access Journals (Sweden)

    Zhao Yu

    2012-09-01

    Full Text Available Abstract Background Electroacupuncture (EA pretreatment can induce the tolerance against focal cerebral ischemia. However, the underlying mechanisms have not been fully understood. Emerging evidences suggest that canonical Notch signaling may be involved in ischemic brain injury. In the present study, we tested the hypothesis that EA pretreatment-induced tolerance against focal cerebral ischemia is mediated by Notch signaling. Results EA pretreatment significantly enhanced Notch1, Notch4 and Jag1 gene transcriptions in the striatum, except Notch1 intracellular domain level, which could be increased evidently by ischemia. After ischemia and reperfusion, Hes1 mRNA and Notch1 intracellular domain level in ischemic striatum in EA pretreatment group were increased and reached the peak at 2 h and 24 h, respectively, which were both earlier than the peak achieved in control group. Intraventricular injection with the γ-secretase inhibitor MW167 attenuated the neuroprotective effect of EA pretreatment. Conclusions EA pretreatment induces the tolerance against focal cerebral ischemia through activation of canonical Notch pathway.

  17. Ethanol production from SPORL-pretreated lodgepole pine : preliminary evaluation of mass balance and process energy efficiency

    Science.gov (United States)

    Junyong Zhu; Wenyuan Zhu; Patricia OBryan; Bruce S. Dien; Shen Tian; Roland Gleisner; X.J. Pan

    2010-01-01

    Lodgepole pine from forest thinnings is a potential feedstock for ethanol production. In this study, lodgepole pine was converted to ethanol with a yield of 276 L per metric ton of wood or 72% of theoretical yield. The lodgepole pine chips were directly subjected to sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) pretreatment and then disk-...

  18. Pretreatment with U(IV) solution for improving the decontamination of ruthenium

    International Nuclear Information System (INIS)

    Huang Haoxin; Qi Zhanshun; Zhu Guohui

    1993-01-01

    The ruthenium decontamination factor in Purex process falls quickly in successive TBP cycles. So, it is necessary to change the chemical states of RuNO complexes in order to improve DF Ru in the uranium purification cycle. Hydrazine nitrate is being used to transform RuNO complexes into in-extractable Ru(III)and Ru(IV). However, hydrazine nitrate may be inverted into hydrazoic acid which is dangerous and can bring an unstable factor. Pretreatment using U(IV) solution provides another method to improve the decontamination of ruthenium in Purex process. 0.02 mol/lU(IV) solution can transform RuNO complexes into inextricable species by heating in water bath. The D Ru can be decreased by a factor of 10-20. U(IV) pretreatment does not bring any harmful chemical in process. The acidity has a very large influence on the effect of pretreatment. The higher the acidity is, the worse the effect will be

  19. Optical monitoring systems for thermal spray processes: droplets behavior and substrate pre-treatments

    Science.gov (United States)

    Kawaguchi, Y.; Kobayashi, N.; Yamagata, Y.; Miyazaki, F.; Yamasaki, M.; Tanaka, J.; Muraoka, K.

    2017-11-01

    Thermal spray is a technique to form molten droplets using either plasma- or combustion-heating, which impinge upon substrates to form coating layers for various purposes, such as anti-corrosion and anti-wear layers. Although it is an established technique having a history of more than a century, operations of spray guns together with preparing suitable substrate surfaces for obtaining good coating layers still rely on experienced technicians. Because of the necessity of meeting more and more stringent requirements for coating quality and cost from customers, there has been a strong need to try to monitor spray processes, so as to obtain the best possible spray coating layers. The basic requirements for such monitoring systems are *reasonably cheap, *easy operation for laypersons, *easy access to targets to be investigated, and *an in-situ capability. The purpose of the present work is to provide suitable optical monitoring systems for (1) droplets behavior and (2) substrate pre-treatments. For the former (1), the first result was already presented at the 17th laser-aided plasma diagnostics meeting (LAPD17) in 2015 in Sapporo, and the results of its subsequent applications into real spray environments are shown in this article in order to validate the previous proposal. Topic (2) is new in the research program, and the proof-of-principle experiment for the proposed method yielded a favorable result. Based on this positive result, an overall strategy is being planned to fulfill the final objective of the optical monitoring of substrate pre-treatments. Details of these two programs (1) and (2) together with the present status are described.

  20. Steam explosion and its combinatorial pretreatment refining technology of plant biomass to bio-based products.

    Science.gov (United States)

    Chen, Hong-Zhang; Liu, Zhi-Hua

    2015-06-01

    Pretreatment is a key unit operation affecting the refinery efficiency of plant biomass. However, the poor efficiency of pretreatment and the lack of basic theory are the main challenges to the industrial implementation of the plant biomass refinery. The purpose of this work is to review steam explosion and its combinatorial pretreatment as a means of overcoming the intrinsic characteristics of plant biomass, including recalcitrance, heterogeneity, multi-composition, and diversity. The main advantages of the selective use of steam explosion and other combinatorial pretreatments across the diversity of raw materials are introduced. Combinatorial pretreatment integrated with other unit operations is proposed as a means to exploit the high-efficiency production of bio-based products from plant biomass. Finally, several pilot- and demonstration-scale operations of the plant biomass refinery are described. Based on the principle of selective function and structure fractionation, and multi-level and directional composition conversion, an integrated process with the combinatorial pretreatments of steam explosion and other pretreatments as the core should be feasible and conform to the plant biomass refinery concept. Combinatorial pretreatments of steam explosion and other pretreatments should be further exploited based on the type and intrinsic characteristics of the plant biomass used, the bio-based products to be made, and the complementarity of the processes. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Alginate-Based Edible Films Delivering Probiotic Bacteria to Sliced Ham Pretreated with High Pressure Processing

    Directory of Open Access Journals (Sweden)

    Foteini Pavli

    2017-08-01

    Full Text Available The aim of the present work was to evaluate the efficacy of Na-alginate edible films as vehicles for delivering probiotic bacteria to sliced ham with or without pretreatment using high pressure processing (HPP. Three strains of probiotic bacteria were incorporated in Na-alginate forming solution. Ham slices (with or without pretreatment using HPP at 500 MPa for 2 min were packed under vacuum in contact with the films and then stored at 4, 8 and 12 °C for 66, 47 and 40 days, respectively. Microbiological analysis was performed in parallel with pH and color measurements. Sensory characteristics were assessed, while the presence and the relative abundance of each probiotic strain during storage was evaluated using pulsed field gel electrophoresis. In ham slices without HPP treatment, probiotic bacteria were enumerated above 106 CFU/g during storage at all temperatures. Same results were obtained in cases of HPP treated samples, but pH measurements showed differences with the latter ones exhibiting higher values. Sensory evaluation revealed that probiotic samples had a more acidic taste and odor than the control ones, however these characteristics were markedly compromised in samples treated with HPP. Overall, the results of the study are promising since probiotic bacteria were successfully delivered in the products by edible films regardless of the HPP treatment.

  2. Alginate-Based Edible Films Delivering Probiotic Bacteria to Sliced Ham Pretreated with High Pressure Processing.

    Science.gov (United States)

    Pavli, Foteini; Kovaiou, Ioanna; Apostolakopoulou, Georgia; Kapetanakou, Anastasia; Skandamis, Panagiotis; Nychas, George-John E; Tassou, Chrysoula; Chorianopoulos, Nikos

    2017-08-29

    The aim of the present work was to evaluate the efficacy of Na-alginate edible films as vehicles for delivering probiotic bacteria to sliced ham with or without pretreatment using high pressure processing (HPP). Three strains of probiotic bacteria were incorporated in Na-alginate forming solution. Ham slices (with or without pretreatment using HPP at 500 MPa for 2 min) were packed under vacuum in contact with the films and then stored at 4, 8 and 12 °C for 66, 47 and 40 days, respectively. Microbiological analysis was performed in parallel with pH and color measurements. Sensory characteristics were assessed, while the presence and the relative abundance of each probiotic strain during storage was evaluated using pulsed field gel electrophoresis. In ham slices without HPP treatment, probiotic bacteria were enumerated above 10⁶ CFU/g during storage at all temperatures. Same results were obtained in cases of HPP treated samples, but pH measurements showed differences with the latter ones exhibiting higher values. Sensory evaluation revealed that probiotic samples had a more acidic taste and odor than the control ones, however these characteristics were markedly compromised in samples treated with HPP. Overall, the results of the study are promising since probiotic bacteria were successfully delivered in the products by edible films regardless of the HPP treatment.

  3. Pretreatment of the macroalgae Chaetomorpha linum for the production of bioethanol - Comparison of five pretreatment technologies

    DEFF Research Database (Denmark)

    Schultz-Jensen, Nadja; Thygesen, Anders; Thomsen, Sune Tjalfe

    2013-01-01

    -assisted pretreatment (PAP) and ball milling (BM), to determine effects of the pretreatment methods on the conversion of C. linum into ethanol by simultaneous saccharification and fermentation (SSF). WO and BM showed the highest ethanol yield of 44. g ethanol/100. g glucan, which was close to the theoretical ethanol......A qualified estimate for pretreatment of the macroalgae Chaetomorpha linum for ethanol production was given, based on the experience of pretreatment of land-based biomass. C. linum was subjected to hydrothermal pretreatment (HTT), wet oxidation (WO), steam explosion (STEX), plasma...... yield of 57. g ethanol/100. g glucan. A 64% higher ethanol yield, based on raw material, was reached after pretreatment with WO and BM compared with unpretreated C. linum, however 50% of the biomass was lost during WO. Results indicated that the right combination of pretreatment and marine macroalgae...

  4. Hydrothermal pretreatments of macroalgal biomass for biorefineries

    DEFF Research Database (Denmark)

    Ruiz, Héctor A.; Rodríguez-Jasso, Rosa M.; Aguedo, Mario

    2015-01-01

    in accordance with the integrated biorefineries. Furthermore, biorefinery concept requires processes that allow efficient utilization of all components of the biomass. The pretreatment step in a biorefinery is often based on hydrothermal principles of high temperatures in aqueous solution. Therefore...

  5. Development of combined nanofiltration and forward osmosis process for production of ethanol from pretreated rice straw.

    Science.gov (United States)

    Shibuya, Masafumi; Sasaki, Kengo; Tanaka, Yasuhiro; Yasukawa, Masahiro; Takahashi, Tomoki; Kondo, Akihiko; Matsuyama, Hideto

    2017-07-01

    A membrane process combining nanofiltraion (NF) and forward osmosis (FO) was developed for the sugar concentration with the aim of high bio-ethanol production from the liquid fraction of rice straw. The commercial NF membrane, ESNA3, was more adequate for removal of fermentation inhibitors (such as acetic acid) than the FO membrane, whereas the commercial FO membrane, TFC-ES, was more adequate for concentration of the sugars than the NF membrane. The liquid fraction was subjected to the following process: NF concentration with water addition (NF (+H2O) )→enzymatic hydrolysis→FO concentration. This NF (+H2O) -FO hybrid process generated a total sugar content of 107g·L -1 . Xylose-assimilating S. cerevisiae produced 24g·L -1 ethanol from the liquid fraction that was diluted 1.5-fold and then concentrated by the NF (+H2O) -FO hybrid process. The NF (+H2O) -FO hybrid process has the potential for optimized ethanol production from pretreated lignocellulosic biomass. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Effect of pelleting on the recalcitrance and bioconversion of dilute-acid pretreated corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Allison E Ray; Amber Hoover; Gary Gresham

    2012-07-01

    Background: Knowledge regarding the performance of densified biomass in biochemical processes is limited. The effects of densification on biochemical conversion are explored here. Methods: Pelleted corn stover samples were generated from bales that were milled to 6.35 mm. Low-solids acid pretreatment and simultaneous saccharification and fermentation were performed to evaluate pretreatment efficacy and ethanol yields achieved for pelleted and ground stover (6.35 mm and 2 mm) samples. Both pelleted and 6.35-mm ground stover were evaluated using a ZipperClave® reactor under high-solids, process-relevant conditions for multiple pretreatment severities (Ro), followed by enzymatic hydrolysis of the washed, pretreated solids. Results: Monomeric xylose yields were significantly higher for pellets (approximately 60%) than for ground formats (approximately 38%). Pellets achieved approximately 84% of theoretical ethanol yield (TEY); ground stover formats had similar profiles, reaching approximately 68% TEY. Pelleting corn stover was not detrimental to pretreatment efficacy for both low- and high-solids conditions, and even enhanced ethanol yields.

  7. Pretreatment of Lignocellulosic Wastes to Improve Ethanol and Biogas Production: A Review

    Directory of Open Access Journals (Sweden)

    Keikhosro Karimi

    2008-09-01

    Full Text Available Lignocelluloses are often a major or sometimes the sole components of different waste streams from various industries, forestry, agriculture and municipalities. Hydrolysis of these materials is the first step for either digestion to biogas (methane or fermentation to ethanol. However, enzymatic hydrolysis of lignocelluloses with no pretreatment is usually not so effective because of high stability of the materials to enzymatic or bacterial attacks. The present work is dedicated to reviewing the methods that have been studied for pretreatment of lignocellulosic wastes for conversion to ethanol or biogas. Effective parameters in pretreatment of lignocelluloses, such as crystallinity, accessible surface area, and protection by lignin and hemicellulose are described first. Then, several pretreatment methods are discussed and their effects on improvement in ethanol and/or biogas production are described. They include milling, irradiation, microwave, steam explosion, ammonia fiber explosion (AFEX, supercritical CO2 and its explosion, alkaline hydrolysis, liquid hot-water pretreatment, organosolv processes, wet oxidation, ozonolysis, dilute- and concentrated-acid hydrolyses, and biological pretreatments.

  8. Impact of Pretreatment Technologies on Saccharification and Isopentenol Fermentation of Mixed Lignocellulosic Feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Jian; George, Kevin W.; Sun, Ning; He, Wei; Li, Chenlin; Stavila, Vitalie; Keasling, Jay D.; Simmons, Blake A.; Lee, Taek Soon; Singh, Seema

    2015-02-28

    In order to enable the large-scale production of biofuels or chemicals from lignocellulosic biomass, a consistent and affordable year-round supply of lignocellulosic feedstocks is essential. Feedstock blending and/or densification offers one promising solution to overcome current challenges on biomass supply, i.e., low energy and bulk densities and significant compositional variations. Therefore, it is imperative to develop conversion technologies that can process mixed pelleted biomass feedstocks with minimal negative impact in terms of overall performance of the relevant biorefinery unit operations: pretreatment, fermentable sugar production, and fuel titers. We processed the mixture of four feedstocks—corn stover, switchgrass, lodgepole pine, and eucalyptus (1:1:1:1 on dry weight basis)—in flour and pellet form using ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate, dilute sulfuric acid (DA), and soaking in aqueous ammonia (SAA) pretreatments. Commercial enzyme mixtures, including cellulases and hemicellulases, were then applied to these pretreated feedstocks at low to moderate enzyme loadings to determine hydrolysis efficiency. Results show significant variations on the chemical composition, crystallinity, and enzymatic digestibility of the pretreated feedstocks across the different pretreatment technologies studied. The advanced biofuel isopentenol was produced during simultaneous saccharification and fermentation (SSF) of pretreated feedstocks using an engineered Escherichia coli strain. Results show that IL pretreatment liberates the most sugar during enzymatic saccharification, and in turn led to the highest isopentenol titer as compared to DA and SAA pretreatments. This study provides insights on developing biorefinery technologies that produce advanced biofuels based on mixed feedstock streams.

  9. An evaluation of dilute acid and ammonia fiber explosion pretreatment for cellulosic ethanol production.

    Science.gov (United States)

    Mathew, Anil Kuruvilla; Parameshwaran, Binod; Sukumaran, Rajeev Kumar; Pandey, Ashok

    2016-01-01

    The challenge associated with cellulosic ethanol production is maximizing sugar yield at low cost. Current research is being focused to develop a pretreatment method to overcome biomass recalcitrance in an efficient way. This review is focused on two major pretreatments: dilute acid (DA) and ammonia fiber explosion (AFEX) pretreatment of corn stover and how these pretreatment cause morphological and chemical changes to corn stover in order to overcome the biomass recalcitrance. This review highlights the key differences of these two pretreatments based on compositional analysis, cellulose and its crystallinity, morphological changes, structural changes to lignin, enzymatic reactivity and enzyme adsorption onto pretreated solids and finally cellulosic ethanol production from the hydrolysate of DA and AFEX treated corn stover. Each stage of the process, AFEX pretreated corn stover was superior to DA treated corn stover. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Efficient saccharification by pretreatment of bagasse pith with ionic liquid and acid solutions simultaneously

    International Nuclear Information System (INIS)

    Wang, Gang; Zhang, Suping; Xu, Wenjuan; Qi, Wei; Yan, Yongjie; Xu, Qingli

    2015-01-01

    Highlights: • Bagasse pith was pretreated by BMIMCl solution containing HCl and water. • Hemicellulose was hydrolyzed to reducing sugars by HCl to maximize total sugar yield. • Cellulose was dissolved by BMIMCl and 95% of cellulose recovery was obtained. • The recovered cellulose was disrupted which is conducive to cellulase hydrolysis. • The total sugars yield is 89.9% obtained from pretreatment and cellulase hydrolysis. - Abstract: Hydrolysis of hemicellulose and disruption of cellulose during pretreatment process are conducive to the following cellulase hydrolysis performance. In this work, bagasse pith was first pretreated by 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) solution containing 0–1.2% hydrochloric acid (HCl) and 30% water. The water (30%) added into the acidic ionic liquid (IL) solutions led to an increase in the biomass loading up to a biomass/IL solutions ratio of 1:10 (wt.%). Hemicellulose was hydrolyzed to reducing sugars by HCl and cellulose was dissolved by [BMIM]Cl. In this process, 76.9% of hemicellulose conversion and 95% of cellulose recovery were obtained. The pretreated bagasse pith was then followed by hydrolysis with commercially available enzymes. The effects of pretreatment temperature, reaction time and acid concentration on cellulase hydrolysis of pretreated bagasse pith were investigated. Pretreatment of bagasse pith with [BMIM]Cl solutions containing 1.0% HCl at 120 °C for 30 min resulted in the glucose concentration of 92.3 g/l and yield of 94.5% after 72 h of cellulase hydrolysis. The maximum total reducing sugars yield reached to 89.9% after pretreatment and cellulase hydrolysis

  11. Pre-treatment hemodynamic features involved with long-term survival of cirrhotic patients after embolization of gastric fundal varices

    International Nuclear Information System (INIS)

    Maruyama, Hitoshi; Okugawa, Hidehiro; Kobayashi, Satoshi; Yoshizumi, Hiroaki; Yokosuka, Osamu

    2010-01-01

    Purpose: To clarify the pre-treatment hemodynamic features involved in the long-term survival of cirrhotic patients with gastric fundal varices (FV) after balloon-occluded retrograde transvenous obliteration (B-RTO). Materials and methods: Eighty-one cirrhotic patients with medium- or large-grade FV treated by B-RTO were enrolled in this retrospective study. Pre-treatment flow volume ratio between gastric vein and portal trunk (GP-R) was obtained by Doppler ultrasound. Results: The cumulative survival rate was 90% at 1 year, 74.8% at 3 years, 57.2% at 5 years, and 45.8% at 7 years without recurrence in a median period of 1148.5 days The survival was poorer in patients with HCC (47% at 3 years, 9.4% at 5 years, p < 0.0001) than without (89.2% at 3 years, 81.9% at 5 years, 67.5% at 7 years), in patients with Child B/C (57.7% at 3 years, 42.1% at 5 years, 28.1% at 7 years, p = 0.0016) than with Child A (91.8% at 3 years, 71.5% at 5 years, 62.1% at 7 years), and in patients with GP-R ≥ 1.0 (58.9% at 3 years, p = 0.0485) than with GP-R < 1.0 (76.3% at 3 years, 62% at 5 years, 49.6% at 7 years). Multivariate analysis identified the presence of HCC (hazard ratio, 12.486; 95% CI, 4.08-38.216; p < 0.0001), Child B/C (hazard ratio, 3.41; 95% CI, 1.594-7.15; p = 0.0051) and GP-R ≥ 1.0 (hazard ratio, 2.701; 95% CI, 1.07-6.15; p = 0.0221) as independent factors for poor prognosis. Conclusion: GP-R ≥ 1.0 on Doppler ultrasound before B-RTO may be a predictive indicator for poor prognosis in cirrhotic patients with FV after B-RTO, in addition to the presence of HCC and severe liver damage.

  12. Pre-treatment hemodynamic features involved with long-term survival of cirrhotic patients after embolization of gastric fundal varices

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Hitoshi, E-mail: maru-cib@umin.ac.j [Department of Medicine and Clinical Oncology, Chiba University Graduate School of Medicine, 1-8-1, Inohana, Chuou-ku, Chiba, 260-8670 (Japan); Okugawa, Hidehiro, E-mail: hideun@yahoo.co.j [Department of Medicine and Clinical Oncology, Chiba University Graduate School of Medicine, 1-8-1, Inohana, Chuou-ku, Chiba, 260-8670 (Japan); Kobayashi, Satoshi, E-mail: kobakobakopa@yahoo.co.j [Department of Medicine and Clinical Oncology, Chiba University Graduate School of Medicine, 1-8-1, Inohana, Chuou-ku, Chiba, 260-8670 (Japan); Yoshizumi, Hiroaki, E-mail: yossih04@yahoo.co.j [Department of Medicine and Clinical Oncology, Chiba University Graduate School of Medicine, 1-8-1, Inohana, Chuou-ku, Chiba, 260-8670 (Japan); Yokosuka, Osamu, E-mail: yokosukao@faculty.chiba-u.j [Department of Medicine and Clinical Oncology, Chiba University Graduate School of Medicine, 1-8-1, Inohana, Chuou-ku, Chiba, 260-8670 (Japan)

    2010-08-15

    Purpose: To clarify the pre-treatment hemodynamic features involved in the long-term survival of cirrhotic patients with gastric fundal varices (FV) after balloon-occluded retrograde transvenous obliteration (B-RTO). Materials and methods: Eighty-one cirrhotic patients with medium- or large-grade FV treated by B-RTO were enrolled in this retrospective study. Pre-treatment flow volume ratio between gastric vein and portal trunk (GP-R) was obtained by Doppler ultrasound. Results: The cumulative survival rate was 90% at 1 year, 74.8% at 3 years, 57.2% at 5 years, and 45.8% at 7 years without recurrence in a median period of 1148.5 days The survival was poorer in patients with HCC (47% at 3 years, 9.4% at 5 years, p < 0.0001) than without (89.2% at 3 years, 81.9% at 5 years, 67.5% at 7 years), in patients with Child B/C (57.7% at 3 years, 42.1% at 5 years, 28.1% at 7 years, p = 0.0016) than with Child A (91.8% at 3 years, 71.5% at 5 years, 62.1% at 7 years), and in patients with GP-R {>=} 1.0 (58.9% at 3 years, p = 0.0485) than with GP-R < 1.0 (76.3% at 3 years, 62% at 5 years, 49.6% at 7 years). Multivariate analysis identified the presence of HCC (hazard ratio, 12.486; 95% CI, 4.08-38.216; p < 0.0001), Child B/C (hazard ratio, 3.41; 95% CI, 1.594-7.15; p = 0.0051) and GP-R {>=} 1.0 (hazard ratio, 2.701; 95% CI, 1.07-6.15; p = 0.0221) as independent factors for poor prognosis. Conclusion: GP-R {>=} 1.0 on Doppler ultrasound before B-RTO may be a predictive indicator for poor prognosis in cirrhotic patients with FV after B-RTO, in addition to the presence of HCC and severe liver damage.

  13. A Conversation on Data Mining Strategies in LC-MS Untargeted Metabolomics: Pre-Processing and Pre-Treatment Steps

    Directory of Open Access Journals (Sweden)

    Fidele Tugizimana

    2016-11-01

    Full Text Available Untargeted metabolomic studies generate information-rich, high-dimensional, and complex datasets that remain challenging to handle and fully exploit. Despite the remarkable progress in the development of tools and algorithms, the “exhaustive” extraction of information from these metabolomic datasets is still a non-trivial undertaking. A conversation on data mining strategies for a maximal information extraction from metabolomic data is needed. Using a liquid chromatography-mass spectrometry (LC-MS-based untargeted metabolomic dataset, this study explored the influence of collection parameters in the data pre-processing step, scaling and data transformation on the statistical models generated, and feature selection, thereafter. Data obtained in positive mode generated from a LC-MS-based untargeted metabolomic study (sorghum plants responding dynamically to infection by a fungal pathogen were used. Raw data were pre-processed with MarkerLynxTM software (Waters Corporation, Manchester, UK. Here, two parameters were varied: the intensity threshold (50–100 counts and the mass tolerance (0.005–0.01 Da. After the pre-processing, the datasets were imported into SIMCA (Umetrics, Umea, Sweden for more data cleaning and statistical modeling. In addition, different scaling (unit variance, Pareto, etc. and data transformation (log and power methods were explored. The results showed that the pre-processing parameters (or algorithms influence the output dataset with regard to the number of defined features. Furthermore, the study demonstrates that the pre-treatment of data prior to statistical modeling affects the subspace approximation outcome: e.g., the amount of variation in X-data that the model can explain and predict. The pre-processing and pre-treatment steps subsequently influence the number of statistically significant extracted/selected features (variables. Thus, as informed by the results, to maximize the value of untargeted metabolomic data

  14. Comparison of different pretreatment strategies for enzymatic hydrolysis of wheat and barley straw

    DEFF Research Database (Denmark)

    Rosgaard, Lisa; Pedersen, Sven; Meyer, Anne Boye Strunge

    2007-01-01

    In biomass-to-ethanol processes a physico-chemical pretreatment of the lignocellulosic biomass is a critical requirement for enhancing the accessibility of the cellulose substrate to enzymatic attack. This report evaluates the efficacy on barley and wheat straw of three different pretreatment pro...

  15. Ultrasonic pretreatment of woodchips for the conversion of cellulose to glucose for bioethanol production

    International Nuclear Information System (INIS)

    Tutun Nugraha; Rettyana Ayuputri; Mohammad Ihsan

    2010-01-01

    In this study, lignocellulosic biomass i.e. the woodchips of Albacia tree (Paraserianthes falcataria) were given different pretreatment methods, i.e. chemical (acid) and physical (ultrasonic). The pretreatment was given in order to convert the cellulose to glucose for the production of bioethanol. 1 % H_2SO_4 was applied for the acid pretreatment. Ultrasound pretreatment was carried out at varied time (10, 20 and 30 minutes) at 600 W, 20 khz before or after the acid pretreatment. Enzymatic attack of the pretreated sample was also applied to enhance the saccharification process of cellulose. The objective of the research was to determine the most effective ultrasonic duration and the best combination of method for enzymatic hydrolysis of the woodchips. The data showed that the highest yield of glucose was achieved at 20 minutes ultrasonic time. It was also found that substantial amount of hydrolysis of cellulose to glucose occur during the ultrasonic stage even without the presence of acid or cellulose enzyme. It is likely that the highly energetic ultrasonic process alone could assist in enhancing rate of hydrolysis of lignocellulosic cellulose into glucose. (author)

  16. DHA involvement in neurotransmission process

    Directory of Open Access Journals (Sweden)

    Vancassel Sylvie

    2007-05-01

    Full Text Available The very high enrichment of the nervous system in the polyunsaturated fatty acids, arachidonic (AA, 20: 4n-6 and docosahexaenoic acids (DHA, 22: 6n-3, is dependant of the dietary availability of their respective precursors, linoleic (18: 2n-6 and_-linolenic acids (18: 3n-3. Inadequate amounts of DHA in brain membranes have been linked to a wide variety of abnormalities ranging from visual acuity and learning irregularities, to psychopathologies. However, the molecular mechanisms involved remain unknown. Several years ago, we hypothesized that a modification of DHA contents of neuronal membranes by dietary modulation could change the neurotransmission function and then underlie inappropriate behavioural response. We showed that, in parallel to a severe loss of brain DHA concomitant to a compensatory substitution by 22:5n-6, the dietary lack of α-linolenic acid during development induced important changes in the release of neurotransmitters (dopamine, serotonin, acetylcholine in cerebral areas specifically involved in learning, memory and reward processes. Data suggested alteration of presynaptic storage process and dysregulations of reciprocal functional interactions between monoaminergic and cholinergic pathways. Moreover, we showed that recovery of these neurochemical changes was possible when the deficient diet was switched to a diet balanced in n-3 and n-6 PUFA before weaning. The next step is to understand the mechanism involved. Particularly, we focus on the study of the metabolic cooperation between the endothelial cell, the astrocyte and the neuron which regulate synaptic transmission.These works could contribute to the understanding of the link between some neuropsychiatric disorders and the metabolism of n-3 PUFA, through their action on neurotransmission.

  17. [Enhancement of anaerobic digestion of excess sludge by acid-alkali pretreatment].

    Science.gov (United States)

    Yuan, Guang-Huan; Zhou, Xing-Qiu; Wu, Jian-Dong

    2012-06-01

    In order to enhance the efficiency of anaerobic digestion of excess sludge, acid-alkali pretreatment method was studied. Three different pretreatment methods (alkali alone,acid-alkali, alkali-acid) were compared to investigate their impacts on hydrolysis and acidification of activated sludge. In addition, their influences on methane-producing in subsequent anaerobic digestion process were also studied. The results showed that the soluble chemical oxygen demand (SCOD) of alkaline treatment alone was about 16% higher than the combining of acid and alkali treatment, SCOD concentration increased to 5406.1 mg x L(-1) after 8 d pretreatment. After treated by acid (pH 4.0, 4 d) and alkali (pH 10.0, 4 d), the acetic acid production and its content in short-chain fatty acids (SCFAs) were higher than other pretreatment methods. And the acetic acid production (as COD/VSS) could reach 74.4 mg x g(-1), accounting for 60.5% of SCFAs. After acid-alkali pretreatment, the C: N ratio of the sludge mixed liquor was about 25, and the C: P ratio was between 35-40, which was more favorable than C: N and C: P ratio of alkali alone and alkali-acid to subsequent anaerobic digestion. The control experiments showed that, after acid-alkali pretreatment, anaerobic digestion cumulative methane yield (CH4/VSS(in)) reached to 136.1 mL x g(-1) at 15 d, which was about 2.5-, 1.6-, and 1.7-fold of the blank (unpretreated), alkali alone pretreatment and alkali-acid pretreatment, respectively. After acid-alkali pretreatment for 8 d and anaerobic digestion for 15 d, the removal efficiency of VSS was about 60.9%, and the sludge reduction effect was better than other pretreatments. It is obvious that the acid-alkali pretreatment method was more favorable to anaerobic digestion and sludge reduction.

  18. Infusion-related reactions to infliximab in patients with rheumatoid arthritis in a clinical practice setting: relationship to dose, antihistamine pretreatment, and infusion number.

    Science.gov (United States)

    Wasserman, Michael J; Weber, Deborah A; Guthrie, Judith A; Bykerk, Vivian P; Lee, Peter; Keystone, Edward C

    2004-10-01

    We describe infusion-related reactions to infliximab (during infusion or within 1 hour postinfusion) in patients with active rheumatoid arthritis (RA) treated in a quaternary care center. We followed 113 patients for a mean of 60.6 +/- 28.9 weeks, obtaining 10.5 +/- 4.9 infusions per patient. We observed 1183 infusions resulting in 104 infusion reactions (8.8%). All reactions resolved within several hours following cessation of the infusion and none was serious enough to warrant hospitalization. Reactions included allergic reactions (pruritus, urticaria) in 4.2% of infusions, cardiopulmonary (hypotension, hypertension, tachycardia) in 3.0%, and miscellaneous reactions (headache, nausea, vomiting) in 2.0%. Reactions occurred in 8.0% of 3 mg/kg infusions and in 10.3% of 5 mg/kg infusions. Reactions occurred in 13.2% of infusions that involved antihistamine pretreatment compared to only 7.5% of infusions that involved no pretreatment. At both infliximab doses, there was a similar frequency of infusion reactions in patients pretreated due to a previous infusion (12.6%) compared to those pretreated strictly based on infusion number (14.7%). A number of the reactions involving antihistamine pretreatment may be explained by known side effects of diphenhydramine, including headache, dizziness, nausea, and palpitations. Infusion-related reactions to infliximab were infrequent, rarely severe, and easily manageable. The frequency of reactions was equivalent in patients treated with 3 mg/kg compared to 5 mg/kg. Reactions were significantly more frequent in infusions where patients were pretreated with the antihistamine diphenhydramine, compared to those not involving pretreatment.

  19. Removal Natural Organic Matter (NOM in Peat Water from Wetland Area by Coagulation-Ultrafiltration Hybrid Process with Pretreatment Two-Stage Coagulation

    Directory of Open Access Journals (Sweden)

    Mahmud Mahmud

    2016-06-01

    Full Text Available The primary problem encountered in the application of membrane technology was membrane fouling. During this time, hybrid process by coagulation-ultrafiltration in drinking water treatment that has been conducted by some research, using by one-stage coagulation. The goal of this research was to investigate the effect of two-stage coagulation as a pretreatment towards performance of the coagulation-ultrafiltration hybrid process for removal NOM in the peat water. Coagulation process, either with the one-stage or two-stage coagulation was very good in removing charge hydrophilic fraction, i.e. more than 98%. NOM fractions of the peat water, from the most easily removed by the two-stage coagulation and one-stage coagulation process was charged hydrophilic>strongly hydrophobic>weakly hydrophobic>neutral hydrophilic. The two-stage coagulation process could removed UV254 and colors with a little better than the one-stage coagulation at the optimum coagulant dose. Neutral hydrophilic fraction of peat water NOM was the most influential fraction of UF membrane fouling. The two-stage coagulation process better in removing the neutral hidrophilic fraction, while removing of the charged hydrophilic, strongly hydrophobic and weakly hydrophobic similar to the one-stage coagulation. Hybrid process by pretreatment with two-stage coagulation, beside can increased removal efficiency of UV254 and color, also can reduced fouling rate of the ultrafiltration membraneIt must not exceed 250 words, contains a brief summary of the text, covering the whole manuscript without being too elaborate on every section. Avoid any abbreviation, unless it is a common knowledge or has been previously stated.

  20. Removal Natural Organic Matter (NOM in Peat Water from Wetland Area by Coagulation-Ultrafiltration Hybrid Process with Pretreatment Two-Stage Coagulation

    Directory of Open Access Journals (Sweden)

    Mahmud Mahmud

    2013-11-01

    Full Text Available The primary problem encountered in the application of membrane technology was membrane fouling. During this time, hybrid process by coagulation-ultrafiltration in drinking water treatment that has been conducted by some research, using by one-stage coagulation. The goal of this research was to investigate the effect of two-stage coagulation as a pretreatment towards performance of the coagulation-ultrafiltration hybrid process for removal NOM in the peat water. Coagulation process, either with the one-stage or two-stage coagulation was very good in removing charge hydrophilic fraction, i.e. more than 98%. NOM fractions of the peat water, from the most easily removed by the two-stage coagulation and one-stage coagulation process was charged hydrophilic>strongly hydrophobic>weakly hydrophobic>neutral hydrophilic. The two-stage coagulation process could removed UV254 and colors with a little better than the one-stage coagulation at the optimum coagulant dose. Neutral hydrophilic fraction of peat water NOM was the most influential fraction of UF membrane fouling. The two-stage coagulation process better in removing the neutral hidrophilic fraction, while removing of the charged hydrophilic, strongly hydrophobic and weakly hydrophobic similar to the one-stage coagulation. Hybrid process by pretreatment with two-stage coagulation, beside can increased removal efficiency of UV254 and color, also can reduced fouling rate of the ultrafiltration membraneIt must not exceed 250 words, contains a brief summary of the text, covering the whole manuscript without being too elaborate on every section. Avoid any abbreviation, unless it is a common knowledge or has been previously stated.

  1. 40 CFR 407.74 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE CATEGORY Canned and Preserved Vegetables Subcategory § 407.74 Pretreatment standards for existing sources...

  2. Microalgal biomass pretreatment for bioethanol production: a review

    Directory of Open Access Journals (Sweden)

    Jesús Velazquez-Lucio

    2018-03-01

    Full Text Available Biofuels derived from microalgae biomass have received a great deal of attention owing to their high potentials as sustainable alternatives to fossil fuels. Microalgae have a high capacity of CO2 fixation and depending on their growth conditions, they can accumulate different quantities of lipids, proteins, and carbohydrates. Microalgal biomass can, therefore, represent a rich source of fermentable sugars for third generation bioethanol production. The utilization of microalgal carbohydrates for bioethanol production follows three main stages: i pretreatment, ii saccharification, and iii fermentation. One of the most important stages is the pretreatment, which is carried out to increase the accessibility to intracellular sugars, and thus plays an important role in improving the overall efficiency of the bioethanol production process. Diverse types of pretreatments are currently used including chemical, thermal, mechanical, biological, and their combinations, which can promote cell disruption, facilitate extraction, and result in the modification the structure of carbohydrates as well as the production of fermentable sugars. In this review, the different pretreatments used on microalgae biomass for bioethanol production are presented and discussed. Moreover, the methods used for starch and total carbohydrates quantification in microalgae biomass are also briefly presented and compared.

  3. Removal of mercury from coal via a microbial pretreatment process

    Science.gov (United States)

    Borole, Abhijeet P [Knoxville, TN; Hamilton, Choo Y [Knoxville, TN

    2011-08-16

    A process for the removal of mercury from coal prior to combustion is disclosed. The process is based on use of microorganisms to oxidize iron, sulfur and other species binding mercury within the coal, followed by volatilization of mercury by the microorganisms. The microorganisms are from a class of iron and/or sulfur oxidizing bacteria. The process involves contacting coal with the bacteria in a batch or continuous manner. The mercury is first solubilized from the coal, followed by microbial reduction to elemental mercury, which is stripped off by sparging gas and captured by a mercury recovery unit, giving mercury-free coal. The mercury can be recovered in pure form from the sorbents via additional processing.

  4. A review on hydrothermal pre-treatment technologies and environmental profiles of algal biomass processing.

    Science.gov (United States)

    Patel, Bhavish; Guo, Miao; Izadpanah, Arash; Shah, Nilay; Hellgardt, Klaus

    2016-01-01

    The need for efficient and clean biomass conversion technologies has propelled Hydrothermal (HT) processing as a promising treatment option for biofuel production. This manuscript discussed its application for pre-treatment of microalgae biomass to solid (biochar), liquid (biocrude and biodiesel) and gaseous (hydrogen and methane) products via Hydrothermal Carbonisation (HTC), Hydrothermal Liquefaction (HTL) and Supercritical Water Gasification (SCWG) as well as the utility of HT water as an extraction medium and HT Hydrotreatment (HDT) of algal biocrude. In addition, the Solar Energy Retained in Fuel (SERF) using HT technologies is calculated and compared with benchmark biofuel. Lastly, the Life Cycle Assessment (LCA) discusses the limitation of the current state of art as well as introduction to new potential input categories to obtain a detailed environmental profile. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Pretreatment of lignocellulosic biomass using Fenton chemistry

    Science.gov (United States)

    Pretreatment is a necessary step in “biomass to biofuel conversion” due to the recalcitrant nature of lignocellulosic biomass. White-rot fungi utilize peroxidases and hydrogen peroxide (in vivo Fenton chemistry) to degrade lignin. In an attempt to mimic this process, solution phase Fenton chemistry ...

  6. A xylanase-aided enzymatic pretreatment facilitates cellulose nanofibrillation.

    Science.gov (United States)

    Long, Lingfeng; Tian, Dong; Hu, Jinguang; Wang, Fei; Saddler, Jack

    2017-11-01

    Although biological pretreatment of cellulosic fiber based on endoglucanases has shown some promise to facilitate cellulose nanofibrillation, its efficacy is still limited. In this study, a xylanase-aided endoglucanase pretreatment was assessed on the bleached hardwood and softwood Kraft pulps to facilitate the downstream cellulose nanofibrillation. Four commercial xylanase preparations were compared and the changes of major fiber physicochemical characteristics such as cellulose/hemicellulose content, gross fiber properties, fiber morphologies, cellulose accessibility/degree of polymerization (DP)/crystallinity were systematically evaluated before and after enzymatic pretreatment. It showed that the synergistic cooperation between endoglucanase and certain xylanase (Biobrite) could efficiently "open up" the hardwood Kraft pulp with limited carbohydrates degradation (cellulose nanofibrillation during mild sonication process (90Wh) with more uniform disintegrated nanofibril products (50-150nm, as assessed by scanning electron microscopy and UV-vis spectroscopy). Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. 40 CFR 407.64 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE CATEGORY Canned and Preserved Fruits Subcategory § 407.64 Pretreatment standards for existing sources. Any...

  8. The effect of thermal pre-treatment of titanium hydride (TiH2) powder in argon condition

    Science.gov (United States)

    Franciska P., L.; Erryani, Aprilia; Annur, Dhyah; Kartika, Ika

    2018-04-01

    Titanium hydride (TiH2) powders are used to enhance the foaming process in the formation of a highly porous metallic material with a cellular structure. But, the low temperature of hydrogen release is one of its problems. The present study, different thermal pre-treatment temperatures were employed to investigate the decomposition behavior of TiH2 to retard or delay a hydrogen gas release process during foaming. As a foaming agent, TiH2 was subjected to various heat treatments prior at 450 and 500°C during 2 hours in argon condition. To study the formation mechanism, the thermal behavior of titanium hydride and hydrogen release are investigated by thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The morphology of pre-treated titanium hydride powders were examined using Scanning Electron Microscope (SEM) while unsure mapping and elemental composition of the pre-treated powders processed by Energy Dispersive Spectroscopy (EDS). To study the phase formation was characterized by X-ray diffraction analysis (XRD). In accordance with the results, an increase in pre-treatment temperature of TiH2 to higher degrees are changing the process of releasing hydrogen from titanium hydride powder. DTA/TGA results showed that thermal pre-treatment TiH2 at 450°C, released the hydrogen gas at 560°C in heat treatment when foaming process. Meanwhile, thermal pre-treatment in TiH2 at 500°C, released the hydrogen gas at 670°C when foaming process. There is plenty of direct evidence for the existence of oxide layers that showed by EDS analysis obtained in SEM. As oxygen is a light element and qualitative proof shows that the higher pre-treatment temperature produces more and thicker oxygen layers on the surface of the TiH2 powder particles. It might the thickness of oxide layer are different from different pre-treatment temperatures, which leading to the differences in the decomposition temperature. But from SEM result that oxidation of the powder does not

  9. Optimization of twin gear-based pretreatment of rice straw for bioethanol production

    International Nuclear Information System (INIS)

    Ahmed, Muhammad Ajaz; Rehman, Muhammd Saif Ur; Terán-Hilares, Ruly; Khalid, Saira; Han, Jong-In

    2017-01-01

    Highlights: • Twin gear reactor is a continuous high solids pretreatment reactor. • RSM was applied to optimize twin gear pretreatment for enzymatic digestibility. • 89% enzymatic digestibility was achieved under optimum conditions. • Thermomechanical pretreatment altered the structural features of rice straw. - Abstract: A laboratory twin-gear reactor (TGR) was investigated as a new means for the pretreatment of high solid lignocelluloses. Response surface methodology based on Box Behnken Design was used to optimize the enzymatic digestibility with respect to the pretreatment process variables: temperature of 50–90 °C, NaOH concentration of 2–6% and no. of cycles of 30–60. The results revealed that the TGR-based pretreatment led to the significant structural alterations through increases in pore size, pore volume, cellulose crystallinity and surface area. SEM images also confirmed the surface modifications in the pretreated rice straw. A response surface quadratic model predicted 90% of the enzymatic digestibility, and it was confirmed experimentally and through the analysis of variance (ANOVA) as well. The TGR extrusion proved to be an effective means for exceedingly high solids lignocellulose.

  10. Evaluation on ecological stability and biodegradation of dyeing wastewater pre-treated by electron beam

    International Nuclear Information System (INIS)

    Lee, M.J.; Park, C.K.; Yoo, D.H.; Lee, J.K.; Lee, B.J.; Han, B.S.; Kim, J.K.; Kim, Y.R.

    2005-01-01

    Biological treatment of dye wastewater pre-treated by electron beam has been performed in order to evaluate the biodegradation and ecological stability of effluent. In the process of electron-beam treatment of wastewater there are utilized chemical transformations of pollutants induced by ionizing radiation. Partial decomposition of pollutant takes place as well as transformations of pollutant molecules that result in improving subsequent purification stages like as biological processing. Dyeing wastewater contains many kind of pollutants which are difficult to be decomposed completely by microorganisms. In this study, biodegradation with dyeing wastewater pre-treated by electron beams was observed. On the other hand, consideration on public acceptance in terms of ecological stability of biological effluent pre-treated by electron beams was given in this study. The results of laboratory investigations on biodegradation and ecological stability of effluent showed that biodegradation of dye wastewater pre-treated by electron beam was enhanced compared to unirradiated one. In the initial stage of biological oxidation regardless of different HRT, dye wastewater pre-treated by electron beam could be oxidized easily compare to without treated one. More number of survived daphnia magna could be observed in the biological effluent pre-treated by electron beam. This means that biological effluent pre-treated by electron beam can be said 'it is safe on the ecological system'

  11. Stakeholder involvement activities in Slovakia. NRA's Commitment to Transparent Regulatory Process. Stakeholder Involvement in the French Regulatory Process - From Public Information to Public Participation. Stakeholder involvement in nuclear decision making in the Russian Federation

    International Nuclear Information System (INIS)

    Ziakova, Marta Chairperson; Nuclear Regulatory Authority of the Slovak Republic; Nuclear Regulation Authority - NRA; Ferapontov, Alexey

    2017-01-01

    Session 2 focused on the regulatory perspectives related to stakeholder involvement in the regulatory decision-making process. Presentations provided the audience with information regarding the international and national legal framework implemented in the Slovak Republic, in France, in Japan and in Russia. Examples of stakeholder involvement, as well as some tools used for this purpose, were presented and discussed. The value of consistency and complementarity between international and national requirements was highlighted. Presentations and discussion confirmed the very close tie between the way the stakeholder involvement process is conducted and the public confidence and perception of reliability the regulatory body may gain, or lose. The four presentations confirmed that stakeholder involvement is a key challenge for maintaining regulatory body credibility, independence and legitimacy. All countries confirmed their commitment to trying to make their stakeholder involvement processes as open, visible, transparent and comprehensive as possible. Involvement represents a long and permanent process which requires investment of time, human resources and money, as well as the ability to reach out, to listen, to share, and to take input into account, while keeping in view the goal of delivering decisions that are as rational and objective as possible. Involving stakeholders is more than informing or communicating. The earlier the stakeholders are involved in the decision-making process, the greater the chance of success. If losing credibility is easy, all regulatory bodies agreed on the long process needed to recover it

  12. Promise of combined hydrothermal/chemical and mechanical refining for pretreatment of woody and herbaceous biomass.

    Science.gov (United States)

    Kim, Sun Min; Dien, Bruce S; Singh, Vijay

    2016-01-01

    Production of advanced biofuels from woody and herbaceous feedstocks is moving into commercialization. Biomass needs to be pretreated to overcome the physicochemical properties of biomass that hinder enzyme accessibility, impeding the conversion of the plant cell walls to fermentable sugars. Pretreatment also remains one of the most costly unit operations in the process and among the most critical because it is the source of chemicals that inhibit enzymes and microorganisms and largely determines enzyme loading and sugar yields. Pretreatments are categorized into hydrothermal (aqueous)/chemical, physical, and biological pretreatments, and the mechanistic details of which are briefly outlined in this review. To leverage the synergistic effects of different pretreatment methods, conducting two or more pretreatments consecutively has gained attention. Especially, combining hydrothermal/chemical pretreatment and mechanical refining, a type of physical pretreatment, has the potential to be applied to an industrial plant. Here, the effects of the combined pretreatment (combined hydrothermal/chemical pretreatment and mechanical refining) on energy consumption, physical structure, sugar yields, and enzyme dosage are summarized.

  13. Effects of ultrasound pretreatment on the characteristic evolutions of drinking water treatment sludge and its impact on coagulation property of sludge recycling process.

    Science.gov (United States)

    Zhou, Zhiwei; Yang, Yanling; Li, Xing

    2015-11-01

    Large amounts of drinking water treatment sludge (DWTS) are produced during the flocculation or flotation process. The recycling of DWTS is important for reducing and reclaiming the waste residues from drinking water treatment. To improve the coagulation step of the DWTS recycling process, power ultrasound was used as a pretreatment to disintegrate the DWTS and degrade or inactivate the constituents that are difficult to remove by coagulation. The effects of ultrasound pretreatment on the characteristics of DWTS, including the extent of disintegration, variation in DWTS floc characteristics, and DWTS dewaterability, were investigated. The capacity of the recycling process to remove particulates and organic matter from low-turbidity surface water compared to a control treatment process without DWTS was subsequently evaluated. The coagulation mechanism was further investigated by analyzing the formation, breakage, and re-growth of re-coagulated flocs. Our results indicated that under the low energy density applied (0.03-0.033 W/mL) for less than 15 min at a frequency of 160 kHz, the level of organic solubilization was less elevated, which was evidenced by the lower release of proteins and polysaccharides and lower fluorescence intensities of humic- and protein-like substances. The applied ultrasound conditions had an adverse effect on the dewaterability of the DWTS. Ultrasound pretreatment had no significant impact on the pH or surface charge of the DWTS flocs, whereas particle size decreased slightly and the specific surface area was moderately increased. The pollution removal capacity decreased somewhat for the recycled sonicated DWTS treatment, which was primarily ascribed to organic solubilization rather than variability in the floc characteristics of sonicated DWTS. The main coagulation mechanism was floc sweeping and physical adsorption. The breakage process of the flocs formed by the recycling process displayed distinct irreversibility, and the flocs were

  14. Improved sugar yields from biomass sorghum feedstocks: comparing low-lignin mutants and pretreatment chemistries.

    Science.gov (United States)

    Godin, Bruno; Nagle, Nick; Sattler, Scott; Agneessens, Richard; Delcarte, Jérôme; Wolfrum, Edward

    2016-01-01

    For biofuel production processes to be economically efficient, it is essential to maximize the production of monomeric carbohydrates from the structural carbohydrates of feedstocks. One strategy for maximizing carbohydrate production is to identify less recalcitrant feedstock cultivars by performing some type of experimental screening on a large and diverse set of candidate materials, or by identifying genetic modifications (random or directed mutations or transgenic plants) that provide decreased recalcitrance. Economic efficiency can also be increased using additional pretreatment processes such as deacetylation, which uses dilute NaOH to remove the acetyl groups of hemicellulose prior to dilute acid pretreatment. In this work, we used a laboratory-scale screening tool that mimics relevant thermochemical pretreatment conditions to compare the total sugar yield of three near-isogenic brown midrib ( bmr ) mutant lines and the wild-type (WT) sorghum cultivar. We then compared results obtained from the laboratory-scale screening pretreatment assay to a large-scale pretreatment system. After pretreatment and enzymatic hydrolysis, the bmr mutants had higher total sugar yields than the WT sorghum cultivar. Increased pretreatment temperatures increased reactivity for all sorghum samples reducing the differences observed at lower reaction temperatures. Deacetylation prior to dilute acid pretreatment increased the total sugar yield for all four sorghum samples, and reduced the differences in total sugar yields among them, but solubilized a sizable fraction of the non-structural carbohydrates. The general trends of increased total sugar yield in the bmr mutant compared to the WT seen at the laboratory scale were observed at the large-scale system. However, in the larger reactor system, the measured total sugar yields were lower and the difference in total sugar yield between the WT and bmr sorghum was larger. Sorghum bmr mutants, which have a reduced lignin content showed

  15. 40 CFR 407.76 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE CATEGORY Canned and Preserved Vegetables Subcategory § 407.76 Pretreatment standards for new sources. Any new source...

  16. 40 CFR 407.66 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE CATEGORY Canned and Preserved Fruits Subcategory § 407.66 Pretreatment standards for new sources. Any new source...

  17. 40 CFR 405.86 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... GUIDELINES AND STANDARDS DAIRY PRODUCTS PROCESSING POINT SOURCE CATEGORY Ice Cream, Frozen Desserts, Novelties and Other Dairy Desserts Subcategory § 405.86 Pretreatment standards for new sources. Any new...

  18. Comparison of gamma irradiation and steam explosion pretreatment for ethanol production from agricultural residues

    International Nuclear Information System (INIS)

    Wang, Ke-qin; Xiong, Xing-yao; Chen, Jing-ping; Chen, Liang; Su, Xiaojun; Liu, Yun

    2012-01-01

    It was evaluated the influence of gamma irradiation and steam explosion pretreatment on the components and the water-soluble sugars of rice straw. Compared with the steam explosion pretreated rice straw, cellucose, hemicellucose and lignin for irradiation pretreated rice sample were much more greatly degraded and the relative content of glucose was significantly enhanced from 6.58% to 47.44%. Interestingly, no glucuronide acid was detected in irradiation pretreated rice straw, while glucuronide acid with the content from 8.5 mg/g to 9.2 mg/g was obtained in steam explosion pretreated sample. Followed by enzymatic hydrolysis, higher concentration of reducing sugars (including glucose and xylose) of irradiation pretreated rice sample (90.3 mg/g) was obtained, which was approximately 2.4- and 1.1- fold higher of the unpretreated (37.2 mg/g) and of steam explosion pretreated sample (85.4 mg/g). To further verify the effectiveness of irradiation pretreatment, characterizations of rice straw, corn stalk and bagasse by an integrated process of dilute acid/enzymatic hydrolysis and irradiation pretreatment were also investigated. -- Highlights: ► We compare irradiation and steam explosion pretreatments for bioethanol production. ► We examine changes in compositions of the components and the water-soluble sugars. ► No glucuronide acid was detected in gamma irradiation pretreated rice straw. ► We evaluate an integrated method of acid/enzyme-hydrolyzed irradiation pretreatment.

  19. Effect of plasma pretreatment on the structure and emission characteristics of carbon nanotubes

    International Nuclear Information System (INIS)

    Uh, Hyung Soo; Lee, Soo Myun; Choi, Seok Rim; Park, Sang Sik; Cho, Euo Sik; Lee, Jong Duk; Kwon, Sang Jik

    2003-01-01

    Carbon nanotubes (CNTs) were grown on Ni-coated TiN/Si substrates by using microwave plasma chemical vapor deposition with a gas mixture of H 2 /CH 4 at a low temperature of 500 .deg. C. The effect of H 2 plasma pretreatment on the diameter of grown CNTs was investigated. We found that the average diameter of CNTs could be easily controlled by using the H 2 -plasma pretreatment time before CNTs growth and varied from 36 nm to 26 nm as the pretreatment time changed from 5 min to 15 min. However, any further increase in the pretreatment time gave rise to a rapid decrease in CNTs growth. After 25 min of the plasma pretreatment, scanning electron microscopy observation exhibited the destruction of the CNTs. The impact of the plasma pretreatment time on the emission behavior of CNTs was also investigated in a diode-type electron-emission configuration. The variation of the CNT diameter due to the plasma pretreatment caused a drastic change in emission properties. The turn-on voltages of CNT emitters varied from 3.5 V/μm to 9 V/μm, depending on the hydrogen-plasma pretreatment conditions. The close relationship between the electron-emission characteristics and the pretreatment time indicates that the pretreatment condition may be a key process parameter in CNTs growth for field-emission displays and should be optimized.

  20. Democratizing Process Innovation? On Citizen Involvement in Public Sector BPM

    Science.gov (United States)

    Niehaves, Björn; Malsch, Robert

    ‘Open Innovation’ has been heavily discussed for product innovations; however, an information systems (IS) perspective on ‘process innovation’ has not yet been taken. Analyzing the example of the public sector in Germany, the paper seeks to investigate the factors that hinder and support ‘open process innovation’, a concept we define as the involvement of citizens in business process management (BPM) activities. With the help of a quantitative study (n=358), six factors are examined for their impact on citizen involvement in local government BPM initiatives. The results show that citizen involvement in reform processes is not primarily motivated by the aim of cost reduction, but rather related to legitimacy reasons and the intent to increase employee motivation. Based on these findings, implications for (design) theory and practice are discussed: Instead of detailed collaborative business processes modeling, the key of citizen involvement in public sector BPM lies in communication and mutual understanding.

  1. Evaluation of Alkali-Pretreated Soybean Straw for Lignocellulosic Bioethanol Production

    Directory of Open Access Journals (Sweden)

    Seonghun Kim

    2018-01-01

    Full Text Available Soybean straw is a renewable resource in agricultural residues that can be used for lignocellulosic bioethanol production. To enhance enzymatic digestibility and fermentability, the biomass was prepared with an alkali-thermal pretreatment (sodium hydroxide, 121°C, 60 min. The delignification yield was 34.1~53%, in proportion to the amount of sodium hydroxide, from 0.5 to 3.0 M. The lignin and hemicellulose contents of the pretreated biomass were reduced by the pretreatment process, whereas the proportion of cellulose was increased. Under optimal condition, the pretreated biomass consisted of 74.0±0.1% cellulose, 10.3±0.1% hemicellulose, and 10.1±0.6% lignin. During enzymatic saccharification using Cellic® CTec2 cellulase, 10% (w/v of pretreated soybean straw was hydrolyzed completely and converted to 67.3±2.1 g/L glucose and 9.4±0.5 g/L xylose with a 90.9% yield efficiency. Simultaneous saccharification and fermentation of the pretreated biomass by Saccharomyces cerevisiae W303-1A produced 30.5±1.2 g/L ethanol in 0.5 L fermented medium containing 10% (w/v pretreated biomass after 72 h. The ethanol productivity was 0.305 g ethanol/g dry biomass and 0.45 g ethanol/g glucose after fermentation, with a low concentration of organic acid metabolites. Also, 82% of fermentable sugar was used by the yeast for ethanol fermentation. These results show that the combination of alkaline pretreatment and biomass hydrolysate is useful for enhancing bioethanol productivity using delignified soybean straw.

  2. Pengaruh Pretreatment Secara Alkalisasi-Resistive Heating terhadap Kandungan Lignoselulosa Jerami Padi

    Directory of Open Access Journals (Sweden)

    Dewi Maya Maharani

    2017-09-01

    Full Text Available Cellulose is a potential biomass that is used for bioethanol production and commonly present in agricultural residues like rice straw. Cellulose is an important material to produce glucose and bioethanol, but it is covered by lignin and hemicellulose bonds to form a lignocellulose.  Bioethanol production using basic material containing cellulose requires special attention in the process of pretreatment for lignin degradation process and increase the accessible surface and decrystallize cellulose. The aim of this research was to apply alkalization and resistive heating combine method for rice straw pretreatment process before further being converted into bioethanol and to determine the effects of heating temperature and NaOH concentration on the content of  lignin, cellulose, and hemicellulose. The reactor had been designed for resistive heating process. Rice straw that was resized into 100 mesh has dissolved with 0.03 M, 0.05 M, and 0.07 M NaOH and heated with resistive heating temperature of 75 oC, 85 oC, and 99 oC. Cellulose is a raw material that will be further converted into glucose. So that, the selected optimum conditions of this study were  pretreatment with the highest increase of cellulose content level until 8.88% and resulted decreasing levels of lignin (1.39% and hemicellulose (4.33% by temperature  75 oC and 0.07 M NaOH concentration. Resistive heating that combine with alkalization can be used for rice straw pretreatment process that reduce lignin and hemicellulose content as well as increasing cellulose content.   ABSTRAK Selulosa merupakan biomassa yang potensial digunakan untuk produksi bioetanol dan banyak ditemukan di residu pertanian seperti jerami padi. Selulosa merupakan material penting yang dapat dikonversi menjadi glukosa kemudian dikonversi menjadi bioetanol, namun selulosa pada alam dilapisi oleh ikatan lignin dan hemiselulosa menjadi lignoselulosa. Pembuatan bioetanol berbasis selulosa membutuhkan proses

  3. Further development of chemical and biological processes for production of bioethanol: Optimisation of pre-treatment processes and characterisation of products

    Energy Technology Data Exchange (ETDEWEB)

    Thomsen, Anne Belinda; Schmidt, Anette Skammelsen

    1999-03-01

    The efficiency of several processes for pre-treatment of lignocellulose has been investigated to provide feedstock for enzymatic hydrolysis and fermentation. Wet oxidation (WO) (with and without alkaline) has been investigated for wheat straw, birch wood, and willow treating 60 g/L. Three different harvest years of wheat straw were included to evaluate the effect of crop variation from year to year. Comparative studies were made using steaming and steam explosion of wheat straw. Alkaline WO fractionated wheat straw efficiently into solubilised hemicellulose and a highly convertible cellulose fraction. High oxygen (12 bar) during WO and low lignin in treated fibres resulted in highly convertible cellulose. Different optimal reaction conditions were found for different harvest years. For straw 1993 and 1997, conditions were 185 deg. C, 15 minutes resulting in 9-10 g/L solubilised hemicellulose and 63-67% cellulose convertibility. For straw 1994, conditions were 195 deg. C, 5 minutes resulting in 7.5 g/L solubilised hemicellulose and 96% cellulose convertibility. For willow, the optimal pre-treatment was WO without alkaline using 185 deg. C, 15 minutes, giving 8.2 g/L hemicellulose in solution and 50% cellulose convertibility. For birch wood, the best process conditions were hydrothermal treatment (without oxygen and alkaline). At 200 deg. C and 15 minutes, 8 g/L hemicellulose was solubilised with high recoveries for both polysaccharides, however, poor cellulose convertibility was found (<30%). Alkaline WO resulted in the highest cellulose convertibility but low contents of solubilised hemicellulose (<4 g/L). In general, formation of furfural was avoided by adding alkaline during wet oxidation. In the absence of alkaline, furfural formation was higher (up to 130 mg/100 g wheat straw) than that of steam explosion (43 mg/100 g straw). Formation of carboxylic acids was highest during alkaline wet oxidation and highest for birch wood (up to 8 g/L). Minor amounts of

  4. Microwave assisted acid and alkali pretreatment of Miscanthus biomass for biorefineries

    Directory of Open Access Journals (Sweden)

    Zongyuan Zhu

    2015-10-01

    Full Text Available Miscanthus is a major bioenergy crop in Europe and a potential feedstock for second generation biofuels. Thermochemical pretreatment is a significant step in the process of converting lignocellulosic biomass into fermentable sugars. In this work, microwave energy was applied to facilitate NaOH and H2SO4 pretreatments of Miscanthus. This was carried out at 180 ℃ in a monomode microwave cavity at 300 W. Our results show that H2SO4 pretreatment contributes to the breakdown of hemicelluloses and cellulose, leading to a high glucose yield. The maximum sugar yield from available carbohydrates during pretreatment is 75.3% (0.2 M H2SO4 20 Min, and glucose yield is 46.7% under these conditions. NaOH and water pretreatments tend to break down only hemicellulose in preference to cellulose, contributing to high xylose yield. Compared to conventional heating NaOH/H2SO4 pretreatment, 12 times higher sugar yield was obtained by using microwave assisted pretreatment within half the time. NaOH pretreatments lead to a significantly enhanced digestibility of the residue, because the effective removal of lignin and hemicellulose makes cellulose fibres more accessible to cellulases. Morphological study of biomass shows that the tightly packed fibres in the Miscanthus were dismantled and exposed under NaOH condition. We studied sugar degradation under microwave assisted H2SO4 conditions. The results shows that 6-8% biomass was converted into levulinic acid (LA during pretreatment, showing the possibility of using microwave technology to produce LA from biomass. The outcome of this work shows great potential for using microwave in the thermo-chemical pretreatment for biomass and also selective production of LA from biomass.

  5. Sewage sludge pretreatment and disposal. (Latest citations from the NTIS Bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    The bibliography contains citations concerning techniques and equipment used in the pretreatment processes and disposal of sewage sludges. Topics include resource and energy recovery operations, land disposal, composting, ocean disposal, and incineration. Digestion, dewatering, and disinfection are among the pretreatment processes discussed. Environmental aspects, including the effects on soils, plants, and animals, are also presented. (Contains 250 citations and includes a subject term index and title list.)

  6. Changes in various physical/chemical parameters of Pinus pinaster wood after steam explosion pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Negro, M.J.; Manzanares, P.; Oliva, J.M.; Ballesteros, I.; Ballesteros, M. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Madrid (Spain). Departamento de Energias Renovables

    2003-09-01

    Steam-explosion process can be satisfactorily used as a pretreatment in ethanol production from lignocellulosic biomass. Traditionally, pretreatment effectiveness is evaluated in terms of hemicellulose solubilization, enzymatic convertibility of cellulosic fraction, and recovery of both polysaccharides. In this study some parameters different from composition (main components) have been evaluated as an alternative tool to characterise the effect of steaming pretreatment on lignocellulosic materials. The effect of the most important variables in steam explosion pretreatment (temperature, residence time and chip size) on various physical/chemical parameters of pine biomass were investigated. Changes in O/C and H/C atomic ratios, colour analysis, elementary composition, water drop penetration time, organic soluble content, cellulose crystallinity index, and thermogravimetric analysis after the pretreatment were evaluated. Furthermore the influence of operational pretreatment variables on all such parameters and their interactions were examined with the Yates' algorithm. (author)

  7. Changes in various physical/chemical parameters of Pinus pinaster wood after steam explosion pretreatment

    International Nuclear Information System (INIS)

    Negro, M.J.; Manzanares, P.; Oliva, J.M.; Ballesteros, I.; Ballesteros, M.

    2003-01-01

    Steam-explosion process can be satisfactorily used as a pretreatment in ethanol production from lignocellulosic biomass. Traditionally, pretreatment effectiveness is evaluated in terms of hemicellulose solubilization, enzymatic convertibility of cellulose fraction, and recovery of both polysaccharides. In this study some parameters different from composition (main components) have been evaluated as an alternative tool to characterise the effect of steaming pretreatment on lignocellulosic materials. The effect of the most important variables in steam explosion pretreatment (temperature, residence time and chip size) on various physical/chemical parameters of pine biomass were investigated. Changes in O/C and H/C atomic ratios, colour analysis, elementary composition, water drop penetration time, organic soluble content, cellulose cristallinity index, and thermogravimetric analysis after the pretreatment were evaluated. Furthermore the influence of operational pretreatment variables on all such parameters and their interactions were examined with the Yates' algorithm

  8. Comparison of ultrasonic and CO₂laser pretreatment methods on enzyme digestibility of corn stover.

    Science.gov (United States)

    Tian, Shuang-Qi; Wang, Zhen-Yu; Fan, Zi-Luan; Zuo, Li-Li

    2012-01-01

    To decrease the cost of bioethanol production, biomass recalcitrance needs to be overcome so that the conversion of biomass to bioethanol becomes more efficient. CO(2) laser irradiation can disrupt the lignocellulosic physical structure and reduce the average size of fiber. Analyses with Fourier transform infrared spectroscopy, specific surface area, and the microstructure of corn stover were used to elucidate the enhancement mechanism of the pretreatment process by CO(2) laser irradiation. The present work demonstrated that the CO(2) laser had potential to enhance the bioconversion efficiency of lignocellulosic waste to renewable bioethanol. The saccharification rate of the CO(2) laser pretreatment was significantly higher than ultrasonic pretreatment, and reached 27.75% which was 1.34-fold of that of ultrasonic pretreatment. The results showed the impact of CO(2) laser pretreatment on corn stover to be more effective than ultrasonic pretreatment.

  9. Mechanical pretreatment for improved adhesion of diamond coatings

    International Nuclear Information System (INIS)

    Toenshoff, H.K.; Mohlfeld, A.; Gey, C.; Winkler, J.

    1999-01-01

    Diamond coatings are mainly used in cutting processes due to their tribological characteristics. They show a high hardness, low friction coefficient, high wear resistance and good chemical inertness. In relation to polycrystalline diamond (PCD)-tipped cutting inserts, especially the advantageous chemical stability of diamond coatings is superior as no binder phases between diamond grains are used. However, the deposition of adherent high-quality diamond coatings has been found difficult. Thus, substrate pretreatment is utilised to improve film adhesion. This investigation is based on water peening of the substrate material before coating. The investigation revealed best results for diamond film adhesion on pretreated substrates compared to conventional diamond coatings on cemented carbide tools applied with the CVD hot-filament process. In final cutting tests with increased film adhesion trough water peened cutting tools an improved wear behavior was detected. (orig.)

  10. Heat pretreatment-induced activation of gadolinium surfaces towards the initial precipitation of hydrides

    International Nuclear Information System (INIS)

    Benamar, G.; Schweke, D.; Shamir, N.; Zalkind, S.; Livneh, T.; Danon, A.; Kimmel, G.; Mintz, M.H.

    2010-01-01

    A vacuum heat pretreatment is applied, in order to enhance the reactivity of hydride-forming metals towards hydrogen reaction. For gadolinium, as for other rare-earth metals and some actinides, pretreatment temperatures of about 470 K are sufficient to induce such activation. The different factors that may be involved in that activation mechanism are identified and analyzed for gadolinium and their role is evaluated. It is concluded that the most prominent effect is desorption of surface hydroxyl groups, which impede the dissociative chemisorptions of hydrogen.

  11. Pretreatment of grass waste using combined ionizing radiation-acid treatment for enhancing fermentative hydrogen production.

    Science.gov (United States)

    Yang, Guang; Wang, Jianlong

    2018-05-01

    In this study, the combined ionizing radiation-acid pretreatment process was firstly applied to enhance hydrogen fermentation of grass waste. Results showed that the combined pretreatment synergistically enhanced hydrogen fermentation of grass waste. The SCOD and soluble polysaccharide contents of grass waste increased by 1.6 and 2.91 times after the combined pretreatment, respectively. SEM observation and crystallinity test showed the combined pretreatment effectively disrupted the grass structure. Owing to the more favorable substrate conditions, the hydrogen yield achieved 68 mL/g-dry grass added after the combined pretreatment, which was 161.5%, 112.5% and 28.3% higher than those from raw, ionizing radiation pretreated and acid pretreated grass waste, respectively. The VS removal also increased from 13.9% to 25.6% by the combined pretreatment. Microbial community analysis showed that the abundance of dominant hydrogen producing genus Clostridium sensu stricto 1 increased from 37.9% to 69.4% after the combined pretreatment, which contributed to more efficient hydrogen fermentation. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Influence of ultrasonication and Fenton oxidation pre-treatment on rheological characteristics of wastewater sludge.

    Science.gov (United States)

    Pham, T T H; Brar, S K; Tyagi, R D; Surampalli, R Y

    2010-01-01

    The effect of ultrasonication and Fenton oxidation as physico-chemical pre-treatment processes on the change of rheology of wastewater sludge was investigated in this study. Pre-treated and raw sludges displayed non-Newtonian rheological behaviour with shear thinning as well as thixotropic properties for total solids ranging from 10 g/L to 40 g/L. The rheological models, namely, Bingham plastic, Casson law, NCA/CMA Casson, IPC Paste, and power law were also studied to characterize flow of raw and pre-treated sludges. Among all rheological models, the power law was more prominent in describing the rheology of the sludges. Pre-treatment processes resulted in a decrease in pseudoplasticity of sludge due to the decrease in consistency index K varying from 42.4 to 1188, 25.6 to 620.4 and 52.5 to 317.9; and increase in flow behaviour index n changing from 0.5 to 0.35, 0.62 to 0.55 and 0.63 to 0.58, for RS, UlS and FS, respectively at solids concentration 10-40 g/L. The correlation between improvement of biodegradability and dewaterability, decrease in viscosity, and change in particle size as a function of sludge pre-treatment process was also investigated. Fenton oxidation facilitated sludge filterability resulting in capillary suction time values which were approximately 50% of the raw sludges, whereas ultrasonication with high input energy deteriorated the filterability. Biodegradability was also enhanced by the pre-treatment processes and the maximum value was obtained (64%, 77% and 73% for raw, ultrasonicated and Fenton oxidized sludges, respectively) at total solids concentration of 25 g/L. Hence, pre-treatment of wastewater sludge modified the rheological properties so that: (1) the flowability of sludge was improved for transport through the treatment train (via pipes and pumps); (2) the dewaterability of wastewater sludge was enhanced for eventual disposal and; (3) the assimilation of nutrients by microorganisms for further value-addition was increased.

  13. pH catalyzed pretreatment of corn bran for enhanced enzymatic arabinoxylan degradation

    DEFF Research Database (Denmark)

    Agger, Jane; Johansen, Katja Salomon; Meyer, Anne S.

    2011-01-01

    Corn bran is mainly made up of the pericarp of corn kernels and is a byproduct stream resulting from the wet milling step in corn starch processing. Through statistic modeling this study examined the optimization of pretreatment of corn bran for enzymatic hydrolysis. A low pH pretreatment (pH 2......, 150°C, 65min) boosted the enzymatic release of xylose and glucose and maximized biomass solubilization. With more acidic pretreatment followed by enzymatic hydrolysis the total xylose release was maximized (at pH 1.3) reaching ∼50% by weight of the original amount present in destarched corn bran......, but the enzyme catalyzed xylose release was maximal after pretreatment at approx. pH 2. The total glucose release peaked after pretreatment of approx. pH 1.5 with an enzymatic release of approx. 68% by weight of the original amounts present in destarched corn bran. For arabinose the enzymatic release...

  14. Pretreatment methods to obtain pumpable high solid loading wood–water slurries for continuous hydrothermal liquefaction systems

    DEFF Research Database (Denmark)

    Dãrãbana, Iulia-Maria; Rosendahl, Lasse Aistrup; Pedersen, Thomas Helmer

    2015-01-01

    Feedstock pretreatment is a prerequisite step for continuous processing of lignocellulosic biomass through HTL, in order to facilitate the pumpability of biomass aqueous slurries. Until now, HTL feedstock pumpability could only be achieved at solid mass content below 15%. In this work, two...... pretreatment methods to obtain wood-based slurries with more than 20% solid mass content, for continuous processing in HTL systems, are proposed. The effect of biomass particle size and pretreatment method on the feedstock pumpability is analyzed. The experimental results show that pumpable wood-based slurries...

  15. Improved Activity of a Thermophilic Cellulase, Cel5A, from Thermotoga maritima on Ionic Liquid Pretreated Switchgrass

    Science.gov (United States)

    Chen, Zhiwei; Pereira, Jose H.; Liu, Hanbin; Tran, Huu M.; Hsu, Nathan S. Y.; Dibble, Dean; Singh, Seema; Adams, Paul D.; Sapra, Rajat; Hadi, Masood Z.; Simmons, Blake A.; Sale, Kenneth L.

    2013-01-01

    Ionic liquid pretreatment of biomass has been shown to greatly reduce the recalcitrance of lignocellulosic biomass, resulting in improved sugar yields after enzymatic saccharification. However, even under these improved saccharification conditions the cost of enzymes still represents a significant proportion of the total cost of producing sugars and ultimately fuels from lignocellulosic biomass. Much of the high cost of enzymes is due to the low catalytic efficiency and stability of lignocellulolytic enzymes, especially cellulases, under conditions that include high temperatures and the presence of residual pretreatment chemicals, such as acids, organic solvents, bases, or ionic liquids. Improving the efficiency of the saccharification process on ionic liquid pretreated biomass will facilitate reduced enzyme loading and cost. Thermophilic cellulases have been shown to be stable and active in ionic liquids but their activity is typically at lower levels. Cel5A_Tma, a thermophilic endoglucanase from Thermotoga maritima, is highly active on cellulosic substrates and is stable in ionic liquid environments. Here, our motivation was to engineer mutants of Cel5A_Tma with higher activity on 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]) pretreated biomass. We developed a robotic platform to screen a random mutagenesis library of Cel5A_Tma. Twelve mutants with 25–42% improvement in specific activity on carboxymethyl cellulose and up to 30% improvement on ionic-liquid pretreated switchgrass were successfully isolated and characterized from a library of twenty thousand variants. Interestingly, most of the mutations in the improved variants are located distally to the active site on the protein surface and are not directly involved with substrate binding. PMID:24244549

  16. Improved activity of a thermophilic cellulase, Cel5A, from Thermotoga maritima on ionic liquid pretreated switchgrass.

    Directory of Open Access Journals (Sweden)

    Zhiwei Chen

    Full Text Available Ionic liquid pretreatment of biomass has been shown to greatly reduce the recalcitrance of lignocellulosic biomass, resulting in improved sugar yields after enzymatic saccharification. However, even under these improved saccharification conditions the cost of enzymes still represents a significant proportion of the total cost of producing sugars and ultimately fuels from lignocellulosic biomass. Much of the high cost of enzymes is due to the low catalytic efficiency and stability of lignocellulolytic enzymes, especially cellulases, under conditions that include high temperatures and the presence of residual pretreatment chemicals, such as acids, organic solvents, bases, or ionic liquids. Improving the efficiency of the saccharification process on ionic liquid pretreated biomass will facilitate reduced enzyme loading and cost. Thermophilic cellulases have been shown to be stable and active in ionic liquids but their activity is typically at lower levels. Cel5A_Tma, a thermophilic endoglucanase from Thermotoga maritima, is highly active on cellulosic substrates and is stable in ionic liquid environments. Here, our motivation was to engineer mutants of Cel5A_Tma with higher activity on 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc] pretreated biomass. We developed a robotic platform to screen a random mutagenesis library of Cel5A_Tma. Twelve mutants with 25-42% improvement in specific activity on carboxymethyl cellulose and up to 30% improvement on ionic-liquid pretreated switchgrass were successfully isolated and characterized from a library of twenty thousand variants. Interestingly, most of the mutations in the improved variants are located distally to the active site on the protein surface and are not directly involved with substrate binding.

  17. Description of waste pretreatment and interfacing systems dynamic simulation model

    International Nuclear Information System (INIS)

    Garbrick, D.J.; Zimmerman, B.D.

    1995-05-01

    The Waste Pretreatment and Interfacing Systems Dynamic Simulation Model was created to investigate the required pretreatment facility processing rates for both high level and low level waste so that the vitrification of tank waste can be completed according to the milestones defined in the Tri-Party Agreement (TPA). In order to achieve this objective, the processes upstream and downstream of the pretreatment facilities must also be included. The simulation model starts with retrieval of tank waste and ends with vitrification for both low level and high level wastes. This report describes the results of three simulation cases: one based on suggested average facility processing rates, one with facility rates determined so that approximately 6 new DSTs are required, and one with facility rates determined so that approximately no new DSTs are required. It appears, based on the simulation results, that reasonable facility processing rates can be selected so that no new DSTs are required by the TWRS program. However, this conclusion must be viewed with respect to the modeling assumptions, described in detail in the report. Also included in the report, in an appendix, are results of two sensitivity cases: one with glass plant water recycle steams recycled versus not recycled, and one employing the TPA SST retrieval schedule versus a more uniform SST retrieval schedule. Both recycling and retrieval schedule appear to have a significant impact on overall tank usage

  18. Optimization of SHINE Process: Design and Verification of Plant-Scale AG 1 Anion-Exchange Concentration Column and Titania Sorbent Pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Stepinski, Dominique C. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Abdul, Momen [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Youker, Amanda J. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Rotsch, David A. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Tkac, Peter [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

    2016-06-01

    Argonne National Laboratory has developed a Mo-recovery and -purification system for the SHINE medical technologies process, which uses a uranyl sulfate solution for the accelerator-driven production of Mo-99. The objective of this effort is to reduce the processing time for the acidification of the Mo-99 product prior to loading onto a concentration column and concentration of the Mo-99 product solution. Two methods were investigated: (1) the replacement of the titania concentration column by an anion-exchange column to decrease processing time and increase the radioiodine-decontamination efficiency and (2) pretreatment of the titania sorbent to improve its effectiveness for the Mo-recovery and -concentration columns. Promising results are reported for both methods.

  19. Study of Crystallinity Index (CrI) of Oil Palm Frond Pretreatment using Aqueous [EMIM][OAc] in a Closed System

    Science.gov (United States)

    Abu Darim, R.; Azizan, A.; Salihon, J.

    2018-05-01

    The objective of this preliminary study is to identify the Crystalinity Index (CrI) of Oil Palm Frond (OPF) pretreated with 40% concentration of 1-ethyl-3-methylimidazolium acetate ionic liquid ([EMIM][OAc]) in a closed system. The morphology and structural changes of the pretreated OPF were examined by using Fourier Transform Infrared Spectrometer (FTIR) and X-Ray Diffraction (XRD). The pretreatment process was carried out in triplicates by loading 40% of [EMIM][OAc] concentration with 10 wt% of OPF loading in the Bio-ionic liquid-reactor. The pretreatment process was conducted for 3 hours with working volume of 70 mL and temperature of 110°C. A Bio-ionic liquid reactor was purposely designed for the lignocellulosic pretreatment by using aqueous ionic liquid at high temperature (higher than boiling point of water). The CrI of OPF pretreated with 40% concentration of [EMM][OAc] in a closed system observed was 9% lower from the untreated OPF and the result showed significant difference with 95% confidence level. Further examination of the untreated and pretreated OPF by using XRD showed that the diffraction pattern of the pretreated OPF samples was decreasing compared to the untreated OPF. The characteristic of the FTIR spectra of the pretreated OPF showed the presence of the cellulose I and occurrence of amorphous cellulosic in the samples. The findings from this study are expected to improve knowledge on pretreatment of OPF by using aqueous [EMIM][OAc] as a green economically viable process for future renewable energy.

  20. K basins sludge removal sludge pretreatment system

    International Nuclear Information System (INIS)

    Chang, H.L.

    1997-01-01

    The Spent Nuclear Fuels Program is in the process of planning activities to remove spent nuclear fuel and other materials from the 100-K Basins as a remediation effort for clean closure. The 105 K- East and K-West Basins store spent fuel, sludge, and debris. Sludge has accumulated in the 1 00 K Basins as a result of fuel oxidation and a slight amount of general debris being deposited, by settling, in the basin water. The ultimate intent in removing the sludge and fuel is to eliminate the environmental risk posed by storing fuel at the K Basins. The task for this project is to disposition specific constituents of sludge (metallic fuel) to produce a product stream through a pretreatment process that will meet the requirements, including a final particle size acceptable to the Tank Waste Remediation System (TWRS). The purpose of this task is to develop a preconceptual design package for the K Basin sludge pretreatment system. The process equipment/system is at a preconceptual stage, as shown in sketch ES-SNF-01 , while a more refined process system and material/energy balances are ongoing (all sketches are shown in Appendix C). Thus, the overall process and 0535 associated equipment have been conservatively selected and sized, respectively, to establish the cost basis and equipment layout as shown in sketches ES- SNF-02 through 08

  1. Effect of Glycerol Pretreatment on Levoglucosan Production from Corncobs by Fast Pyrolysis

    Directory of Open Access Journals (Sweden)

    Liqun Jiang

    2017-11-01

    Full Text Available In this manuscript, glycerol was used in corncobs’ pretreatment to promote levoglucosan production by fast pyrolysis first and then was further utilized as raw material for chemicals production by microbial fermentation. The effects of glycerol pretreatment temperatures (220–240 °C, time (0.5–3 h and solid-to-liquid ratios (5–20% were investigated. Due to the accumulation of crystalline cellulose and the removal of minerals, the levoglucosan yield was as high as 35.8% from corncobs pretreated by glycerol at 240 for 3 h with a 5% solid-to-liquid ratio, which was obviously higher than that of the control (2.2%. After glycerol pretreatment, the fermentability of the recovered glycerol remaining in the liquid stream from glycerol pretreatment was evaluated by Klebsiella pneumoniae. The results showed that the recovered glycerol had no inhibitory effect on the growth and metabolism of the microbe, which was a promising substrate for fermentation. The value-added applications of glycerol could reduce the cost of biomass pretreatment. Correspondingly, this manuscript offers a green, sustainable, efficient and economic strategy for an integrated biorefinery process.

  2. Effect of pre-treatment of Palm oil Mill effluent (POME) and Cassava ...

    African Journals Online (AJOL)

    MICHAEL

    ABSTRACT: Pretreatment measures in effluents' management comprised of phase separation involving sedimentation, aeration to enhance biodegradation and pH neutralization. A randomized complete block design experiment in factorial arrangement was set up to assess effects of aeration, settling and pH neutralization ...

  3. Biodelignification of lignocellulose substrates: An intrinsic and sustainable pretreatment strategy for clean energy production.

    Science.gov (United States)

    Chandel, Anuj K; Gonçalves, Bruna C M; Strap, Janice L; da Silva, Silvio S

    2015-01-01

    Lignocellulosic biomass (LB) is a promising sugar feedstock for biofuels and other high-value chemical commodities. The recalcitrance of LB, however, impedes carbohydrate accessibility and its conversion into commercially significant products. Two important factors for the overall economization of biofuel production is LB pretreatment to liberate fermentable sugars followed by conversion into ethanol. Sustainable biofuel production must overcome issues such as minimizing water and energy usage, reducing chemical usage and process intensification. Amongst available pretreatment methods, microorganism-mediated pretreatments are the safest, green, and sustainable. Native biodelignifying agents such as Phanerochaete chrysosporium, Pycnoporous cinnabarinus, Ceriporiopsis subvermispora and Cyathus stercoreus can remove lignin, making the remaining substrates amenable for saccharification. The development of a robust, integrated bioprocessing (IBP) approach for economic ethanol production would incorporate all essential steps including pretreatment, cellulase production, enzyme hydrolysis and fermentation of the released sugars into ethanol. IBP represents an inexpensive, environmentally friendly, low energy and low capital approach for second-generation ethanol production. This paper reviews the advancements in microbial-assisted pretreatment for the delignification of lignocellulosic substrates, system metabolic engineering for biorefineries and highlights the possibilities of process integration for sustainable and economic ethanol production.

  4. Pretreated of banana pseudo-stem as raw material for enzymatic hydrolysis and bioethanol production

    Directory of Open Access Journals (Sweden)

    Kusmiyati

    2018-01-01

    Full Text Available Development of alternative energy is needed to solve the energy problem, including bioethanol. Banana pseudo-stem is a lignocellulose material that can used to produce bioethanol. Banana pseudo-stem has 28.83% cellulose and 19.39% lignin. The amount of lignin will reduce by pretreatment process. Variations of pretreatment methods by autoclaving of banana-pseudo stem in a steam, 0.5N, 1N, 1.5N, 2N NaOH solutions for 90 minutes were employed. Then the preteated samples were further enzymatic hydrolysed for 24, 48, 72 hours. The fermentation method of simultaneous saccharification and fermentation (SSF was applied using cellulase enzyme and yeast of Saccharomyces cerevisiae for 120 hours. The variation of the pretreatment process by increasing of NaOH concentration solutions led to decreased the lignin content while increased in cellulose content. The lowest lignin content was 11.44% and the highest cellulose was 51.66%. The highest sugar content was 29.8 g/L (at pretreatment 2N NaOH solution, 72 hours hydrolysis. The highest bioethanol amount (4.32 g/L was produced from pretreated banana stem using 2N NaOH solution.

  5. Combined alkali and acid pretreatment of spent mushroom substrate for reducing sugar and biofertilizer production.

    Science.gov (United States)

    Zhu, Hong-Ji; Liu, Jia-Heng; Sun, Li-Fan; Hu, Zong-Fu; Qiao, Jian-Jun

    2013-05-01

    Spent mushroom substrate (SMS) was pretreated with alkaline reagents including potassium hydroxide, lime and ammonia to enhance enzymatic saccharification. Under the best pretreatment conditions (1M KOH, 80 °C, 90 min; 1M lime, 80 °C, 120 min; 10 M ammonia, 70 °C, 120 min), the total reducing sugar (TRS) yield reached 258.6, 204.2 and 251.2 mg/g raw SMS, which were respectively 6.15, 4.86, and 5.98 times of untreated SMS. The effects of pretreatment by above alkaline reagents and sulfuric acid on the composition and structure of SMS were evaluated to provide comparative performance data. A new process, combined alkali and acid (CAA) pretreatment followed by enzymatic hydrolysis, was innovatively proposed to improve the cost-effectiveness and avoid environmental problems. The SMS residue after CAA pretreatment-enzymatic hydrolysis process was converted to biofertilizer with Pichia farinose FL7 and a cell density of 3.0×10(8) cfu/g in biomass was attained. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Opportunities for utilization of non-conventional energy sources for biomass pretreatment.

    Science.gov (United States)

    Singh, Rawel; Krishna, Bhavya B; Kumar, Jitendra; Bhaskar, Thallada

    2016-01-01

    The increasing concerns over the depletion of fossil resources and its associated geo-political issues have driven the entire world to move toward sustainable forms of energy. Pretreatment is the first step in any biochemical conversion process for the production of valuable fuels/chemicals from lignocellulosic biomass to eliminate the lignin and produce fermentable sugars by hydrolysis. Conventional techniques have several limitations which can be addressed by using them in tandem with non-conventional methods for biomass pretreatment. Electron beam and γ (gamma)-irradiation, microwave and ultrasound energies have certain advantages over conventional source of energy and there is an opportunity that these energies can be exploited for biomass pretreatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Dispositional study of opioids in mice pretreated with sympathomimetic agents.

    Science.gov (United States)

    Dambisya, Y M; Chan, K; Wong, C L

    1992-08-01

    Brain and plasma levels of morphine and codeine were determined by an assay method involving solid-phase extraction and ion-pair reversed phase HPLC. Detection was by a variable wavelength UV-detector (for codeine) and an amperometric electro-chemical detector (for morphine) coupled in series. Ephedrine or phenylpropanolamine pretreatment did not interfere with the plasma disposition of morphine, evidenced by overlapping plasma concentration-time profiles. Brain opioid levels were equally unaffected by sympathomimetic pretreatment. The relative ratios of brain to plasma concentrations at the time corresponding to the respective peak anti-nociceptive activity for morphine and codeine revealed no significant differences. It is concluded that single doses of ephedrine and phenylpropanolamine do not affect the disposition of morphine and codeine in mice.

  8. Bonding effectiveness to different chemically pre-treated dental zirconia.

    Science.gov (United States)

    Inokoshi, Masanao; Poitevin, André; De Munck, Jan; Minakuchi, Shunsuke; Van Meerbeek, Bart

    2014-09-01

    The objective of this study was to evaluate the effect of different chemical pre-treatments on the bond durability to dental zirconia. Fully sintered IPS e.max ZirCAD (Ivoclar Vivadent) blocks were subjected to tribochemical silica sandblasting (CoJet, 3M ESPE). The zirconia samples were additionally pre-treated using one of four zirconia primers/adhesives (Clearfil Ceramic Primer, Kuraray Noritake; Monobond Plus, Ivoclar Vivadent; Scotchbond Universal, 3M ESPE; Z-PRIME Plus, Bisco). Finally, two identically pre-treated zirconia blocks were bonded together using composite cement (RelyX Ultimate, 3M ESPE). The specimens were trimmed at the interface to a cylindrical hourglass and stored in distilled water (7 days, 37 °C), after which they were randomly tested as is or subjected to mechanical ageing involving cyclic tensile stress (10 N, 10 Hz, 10,000 cycles). Subsequently, the micro-tensile bond strength was determined, and SEM fractographic analysis performed. Weibull analysis revealed the highest Weibull scale and shape parameters for the 'Clearfil Ceramic Primer/mechanical ageing' combination. Chemical pre-treatment of CoJet (3M ESPE) sandblasted zirconia using Clearfil Ceramic Primer (Kuraray Noritake) and Monobond Plus (Ivoclar Vivadent) revealed a significantly higher bond strength than when Scotchbond Universal (3M ESPE) and Z-PRIME Plus (Bisco) were used. After ageing, Clearfil Ceramic Primer (Kuraray Noritake) revealed the most stable bond durability. Combined mechanical/chemical pre-treatment, the latter with either Clearfil Ceramic Primer (Kuraray Noritake) or Monobond Plus (Ivoclar Vivadent), resulted in the most durable bond to zirconia. As a standard procedure to durably bond zirconia to tooth tissue, the application of a combined 10-methacryloyloxydecyl dihydrogen phosphate/silane ceramic primer to zirconia is clinically highly recommended.

  9. The effect of microwave pretreatment on chemical looping gasification of microalgae for syngas production

    International Nuclear Information System (INIS)

    Hu, Zhifeng; Ma, Xiaoqian; Jiang, Enchen

    2017-01-01

    Highlights: • Microwave pretreatment is beneficial to chemical-looping gasification reaction. • Gasification efficiency and gas yield increased greatly under microwave pretreatment. • 60 s is the optimal microwave pretreatment time in CLG to produce syngas. • Suitable microwave pretreatment can make the structure of solid residue become loose. • 750 W is the optimal microwave pretreatment power in CLG to produce syngas. - Abstract: Chemical-looping gasification (CLG) of Chlorella vulgaris was carried out in a quartz tube reactor under different microwave pretreatment. The product fractional yields, conversion efficiency and analysis of performance parameters were analyzed in order to obtain the characterization and optimal conditions of microwave pretreatment for syngas production. The results indicate that microwave pretreatment is conducive to CLG reaction. Furthermore, the higher power or the longer time in the process of microwave pretreatment could not exhibit a better effect on CLG. In addition, 750 W and 60 s is the optimal microwave pretreatment power and time respectively to obtain a great reducibility of oxygen carrier, high conversion efficiency, high products yield and good LHV. The H_2 yield, LHV, gasification efficiency and gas yield increased obviously from 18.12%, 12.14 MJ/Nm"3, 59.76% and 1.04 Nm"3/kg of untreated Chlorella vulgaris to 24.55%, 13.13 MJ/Nm"3, 72.16% and 1.16 Nm"3/kg of the optimal microwave pretreatment condition, respectively.

  10. Removal of selected nitrogenous heterocyclic compounds in biologically pretreated coal gasification wastewater (BPCGW) using the catalytic ozonation process combined with the two-stage membrane bioreactor (MBR).

    Science.gov (United States)

    Zhu, Hao; Han, Yuxing; Ma, Wencheng; Han, Hongjun; Ma, Weiwei

    2017-12-01

    Three identical anoxic-aerobic membrane bioreactors (MBRs) were operated in parallel for 300 consecutive days for raw (R 1 ), ozonated (R 2 ) and catalytic ozonated (R 3 ) biologically pretreated coal gasification wastewater (BPCGW) treatment. The results demonstrated that catalytic ozonation process (COP) applied asa pretreatment remarkably improved the performance of the unsatisfactory single MBR. The overall removal efficiencies of COD, NH 3 -N and TN in R 3 were 92.7%, 95.6% and 80.6%, respectively. In addition, typical nitrogenous heterocyclic compounds (NHCs) of quinoline, pyridine and indole were completely removed in the integrated process. Moreover, COP could alter sludge properties and reshape microbial community structure, thus delaying the occurrence of membrane fouling. Finally, the total cost for this integrated process was estimated to be lower than that of single MBR. The results of this study suggest that COP is a good option to enhance pollutants removal and alleviate membrane fouling in the MBR for BPCGW treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Permitting plan for project W-236B, initial pretreatment module

    International Nuclear Information System (INIS)

    Tollefson, K.S.

    1995-01-01

    The Tank Waste Remediation System pretreatment process mission is to separate high-level and low-level waste fractions. A comprehensive review of environmental regulations has indicated that several environmental reviews, permits, and approvals are required before construction and operation of the facility. This revised document provides a summary of permit application data requirements, alternative strategies for permit completion and approval, as well as the probability of success for each alternative for the Initial Pretreatment Module resulting from recent revisions to the Tri-Party Agreement

  12. Interpretation of colloidal dyeing of polyester fabrics pretreated with ethyl xanthogenate in terms of zeta potential and surface free energy balance.

    Science.gov (United States)

    Espinosa-Jiménez, M; Padilla-Weigand, R; Ontiveros-Ortega, A; Ramos-Tejada, M M; Perea-Carpio, R

    2003-09-15

    Data are presented on the adsorption of the colloidal dye Disperse Blue 3 onto polyester fabric (Dacron 54, Stile 777), the fabric being pretreated with different amounts of the surfactant potassium ethyl xanthogenate (PEX). This study has been made by means of both the evolution of the zeta potential of the fiber/dye interface and the behaviour of the surface free energy components of the above systems. The kinetics of adsorption of the process of dyeing, using 10(-4) M of PEX in the pretreatment of the fabric, shows that increasing temperature of adsorption decrease the amount of colloidal dye adsorbed onto the fabric. This fact shows that the principal mechanism involved in this adsorption process is physical in nature. The adsorption isotherms of the colloidal dye onto polyester pretreated with different amounts of PEX, shows that the adsorption of the dye is favored with the increase in the concentration of the surfactant used in the pretreatment. This fact shows that the pretreatment with PEX is a very interesting aspect of interest in textile industry. The zeta potential of the system fabric/surfactant shows that this parameter is negative (about -25 mV) for the untreated fiber and decreases in absolute value for increasing concentration of the surfactant on the fiber, the value of the zeta potential of the system being -5 mV for 10(-2) M of PEX. This behavior can be explained for the chemical reaction nucleophilic attack between the carboxyl groups of polyester, ionized at pH 8, and the thiocarbonyl group of the xanthogenate ion. On the other hand, the zeta potential of the system polyester pretreated with PEX/Disperse Blue 3 at increasing concentrations of the surfactant and the dye shows that this parameter increases its negative value strongly with increasing concentration of the surfactant used in the treatment. This can be explained for the hydrogen bonds between the hydroxy groups of the dye and the S- ions of the thiocarbonyl group of the surfactant

  13. Effects of sodium nitroprusside (SNP) pretreatment on UV-B stress tolerance in lettuce (Lactuca sativa L.) seedlings.

    Science.gov (United States)

    Esringu, Aslıhan; Aksakal, Ozkan; Tabay, Dilruba; Kara, Ayse Aydan

    2016-01-01

    Ultraviolet-B (UV-B) radiation is one of the most important abiotic stress factors that could influence plant growth, development, and productivity. Nitric oxide (NO) is an important plant growth regulator involved in a wide variety of physiological processes. In the present study, the possibility of enhancing UV-B stress tolerance of lettuce seedlings by the exogenous application of sodium nitroprusside (SNP) was investigated. UV-B radiation increased the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD) and total phenolic concentrations, antioxidant capacity, and expression of phenylalanine ammonia lyase (PAL) gene in seedlings, but the combination of SNP pretreatment and UV-B enhanced antioxidant enzyme activities, total phenolic concentrations, antioxidant capacity, and PAL gene expression even more. Moreover, UV-B radiation significantly inhibited chlorophylls, carotenoid, gibberellic acid (GA), and indole-3-acetic acid (IAA) contents and increased the contents of abscisic acid (ABA), salicylic acid (SA), malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide radical (O2•(-)) in lettuce seedlings. When SNP pretreatment was combined with the UV-B radiation, we observed alleviated chlorophylls, carotenoid, GA, and IAA inhibition and decreased content of ABA, SA, MDA, H2O2, and O2•(-) in comparison to non-pretreated stressed seedlings.

  14. Enzymatic Saccharification and Ethanol Fermentation of Reed Pretreated with Liquid Hot Water

    Directory of Open Access Journals (Sweden)

    Jie Lu

    2012-01-01

    Full Text Available Reed is a widespread-growing, inexpensive, and readily available lignocellulosic material source in northeast China. The objective of this study is to evaluate the liquid hot water (LHW pretreatment efficiency of reed based on the enzymatic digestibility and ethanol fermentability of water-insoluble solids (WISs from reed after the LHW pretreatment. Several variables in the LHW pretreatment and enzymatic hydrolysis process were optimized. The conversion of glucan to glucose and glucose concentrations are considered as response variables in different conditions. The optimum conditions for the LHW pretreatment of reed area temperature of 180°C for 20min and a solid-to-liquid ratio of 1 : 10. These optimum conditions for the LHW pretreatment of reed resulted in a cellulose conversion rate of 82.59% in the subsequent enzymatic hydrolysis at 50°C for 72 h with a cellulase loading of 30 filter paper unit per gram of oven-dried WIS. Increasing the pretreatment temperature resulted in a higher enzymatic digestibility of the WIS from reed. Separate hydrolysis and fermentation of WIS showed that the conversion of glucan to ethanol reached 99.5% of the theoretical yield. The LHW pretreatment of reed is a suitable method to acquire a high recovery of fermentable sugars and high ethanol conversion yield.

  15. Facile preparation of nitrogen-doped porous carbon from waste tobacco by a simple pre-treatment process and their application in electrochemical capacitor and CO2 capture

    International Nuclear Information System (INIS)

    Sha, Yunfei; Lou, Jiaying; Bai, Shizhe; Wu, Da; Liu, Baizhan; Ling, Yun

    2015-01-01

    Highlights: • A pre-treatment process is used to prepared N-doped carbon from waste biomass. • Waste tobaccos, which are limited for the disposal, are used as the raw materials. • The product shows a specific surface area and nitrogen content. • Its electrochemical performance is better than commercial activated carbon. • Its CO 2 sorption performance is also better than commercial activated carbon. - Abstract: Preparing nitrogen-doped porous carbons directly from waste biomass has received considerable interest for the purpose of realizing the atomic economy. In this study, N-doped porous carbons have been successfully prepared from waste tobaccos (WT) by a simple pre-treatment process. The sample calcinated at 700 °C (WT-700) shows a micro/meso-porous structures with a BET surface area of 1104 m 2 g −1 and a nitrogen content of ca. 19.08 wt.% (EDS). Performance studies demonstrate that WT-700 displays 170 F g −1 electrocapacitivity at a current density of 0.5 A g −1 (in 6 M KOH), and a CO 2 capacity of 3.6 mmol g −1 at 0 °C and 1 bar, and a selectivity of ca. 32 for CO 2 over N 2 at 25 °C. Our studies indicate that it is feasible to prepare N-enriched porous carbons from waste natural crops by a pre-treatment process for potential industrial application

  16. Tank Focus Area Pretreatment Program. FY 1995 Program Management Plan

    International Nuclear Information System (INIS)

    Morrison, M.I.; McGinnis, C.P.; Wilkenson, W.T.; Hunt, R.D.

    1995-02-01

    This program management plan (PMP) describes the FY 1995 project plans for the Pretreatment Program of the Tank Focus Area. The Tank Focus Area is one of five areas of environmental concerns originally identified by the Deputy Assistant Secretary for Technology Development (EM-50). Projects in the Tank Focus Area relate to the remediation of liquid waste stored in underground storage tanks at various US Department of Energy sites. The Pretreatment Program is an organizational unit performing work within the Tank Focus Area. The function of the Pretreatment Program is to develop, test, evaluate, and demonstrate new technologies, with emphasis on separations. The 11 Pretreatment Program projects for FY 1995 are (1) Cesium Extraction Testing, (2) Comprehensive Supernate Treatment, (3) Hot Cell Studies, (4) Cesium Removal Demonstration, (5) Out-of-Tank Evaporator Demonstration, (6) Crossflow Filtration, (7) Technical Interchange with CEA, (8) TRUEX Applications, (9) NAC/NAG Process Studies (conducted at Oak Ridge National Laboratory), (10) NAC/NAG Process and Waste Form Studies (conducted at Florida International University), and (11) Program Management. Section 2 of this PMP contains a separate subsection for each FY 1995 project. A brief description of the project, a schedule of major milestones, and a breakdown of costs are provided for each project. The PMP also contains sections that describe the project controls that are in place. Quality assurance, document control, the project management system, and the management organization are described in these sections

  17. PRETREATMENT TECHNOLOGIES IN BIOETHANOL PRODUCTION FROM LIGNOCELLULOSIC BIOMASS

    Directory of Open Access Journals (Sweden)

    Vanja Janušić

    2008-07-01

    Full Text Available Bioethanol is today most commonly produced from corn grain and sugar cane. It is expected that there will be limits to the supply of these raw materials in the near future. Therefore, lignocellulosic biomass, namely agricultural and forest waste, is seen as an attractive feedstock for future supplies of ethanol. Lignocellulosic biomass consists of lignin, hemicellulose and cellulose. Indeed, complexicity of the lignocellulosic biomass structure causes a pretreatment to be applied prior to cellulose and hemicellulose hydrolysis into fermentable sugars. Pretreatment technologies can be physical (mechanical comminution, pyrolysis, physico-chemical (steam explosion, ammonia fiber explosion, CO2 explosion, chemical (ozonolysis, acid hydrolysis, alkaline hydrolysis, oxidative delignification, organosolvent process and biological ones.

  18. Structural characterization of alkaline hydrogen peroxide pretreated grasses exhibiting diverse lignin phenotypes

    Science.gov (United States)

    2012-01-01

    Background For cellulosic biofuels processes, suitable characterization of the lignin remaining within the cell wall and correlation of quantified properties of lignin to cell wall polysaccharide enzymatic deconstruction is underrepresented in the literature. This is particularly true for grasses which represent a number of promising bioenergy feedstocks where quantification of grass lignins is particularly problematic due to the high fraction of p-hydroxycinnamates. The main focus of this work is to use grasses with a diverse range of lignin properties, and applying multiple lignin characterization platforms, attempt to correlate the differences in these lignin properties to the susceptibility to alkaline hydrogen peroxide (AHP) pretreatment and subsequent enzymatic deconstruction. Results We were able to determine that the enzymatic hydrolysis of cellulose to to glucose (i.e. digestibility) of four grasses with relatively diverse lignin phenotypes could be correlated to total lignin content and the content of p-hydroxycinnamates, while S/G ratios did not appear to contribute to the enzymatic digestibility or delignification. The lignins of the brown midrib corn stovers tested were significantly more condensed than a typical commercial corn stover and a significant finding was that pretreatment with alkaline hydrogen peroxide increases the fraction of lignins involved in condensed linkages from 88–95% to ~99% for all the corn stovers tested, which is much more than has been reported in the literature for other pretreatments. This indicates significant scission of β-O-4 bonds by pretreatment and/or induction of lignin condensation reactions. The S/G ratios in grasses determined by analytical pyrolysis are significantly lower than values obtained using either thioacidolysis or 2DHSQC NMR due to presumed interference by ferulates. Conclusions It was found that grass cell wall polysaccharide hydrolysis by cellulolytic enzymes for grasses exhibiting a diversity of

  19. Structural characterization of alkaline hydrogen peroxide pretreated grasses exhibiting diverse lignin phenotypes

    Directory of Open Access Journals (Sweden)

    Li Muyang

    2012-06-01

    Full Text Available Abstract Background For cellulosic biofuels processes, suitable characterization of the lignin remaining within the cell wall and correlation of quantified properties of lignin to cell wall polysaccharide enzymatic deconstruction is underrepresented in the literature. This is particularly true for grasses which represent a number of promising bioenergy feedstocks where quantification of grass lignins is particularly problematic due to the high fraction of p-hydroxycinnamates. The main focus of this work is to use grasses with a diverse range of lignin properties, and applying multiple lignin characterization platforms, attempt to correlate the differences in these lignin properties to the susceptibility to alkaline hydrogen peroxide (AHP pretreatment and subsequent enzymatic deconstruction. Results We were able to determine that the enzymatic hydrolysis of cellulose to to glucose (i.e. digestibility of four grasses with relatively diverse lignin phenotypes could be correlated to total lignin content and the content of p-hydroxycinnamates, while S/G ratios did not appear to contribute to the enzymatic digestibility or delignification. The lignins of the brown midrib corn stovers tested were significantly more condensed than a typical commercial corn stover and a significant finding was that pretreatment with alkaline hydrogen peroxide increases the fraction of lignins involved in condensed linkages from 88–95% to ~99% for all the corn stovers tested, which is much more than has been reported in the literature for other pretreatments. This indicates significant scission of β-O-4 bonds by pretreatment and/or induction of lignin condensation reactions. The S/G ratios in grasses determined by analytical pyrolysis are significantly lower than values obtained using either thioacidolysis or 2DHSQC NMR due to presumed interference by ferulates. Conclusions It was found that grass cell wall polysaccharide hydrolysis by cellulolytic enzymes for grasses

  20. Optimization on Pretreatment Conditions of Seaweed Liquid Waste for Bio ethanol Production

    International Nuclear Information System (INIS)

    Nur Zatul-Iffah Zakaria; Dachyar Arbain; Mohd Noor Ahmad; Mohd Irfan Hatim Mohamed Dzahir

    2015-01-01

    Seaweed liquid waste (SLW) from a non-conventional seaweed (Gracilaria sp.) drying process where the seaweed is ruptured and filter-squeezed has been investigated. The liquid contains proteins and minerals which potentially pollute the environment if it is not been properly treated. For that reason, this paper deals with study on the feasibility of SLW utilization as a feedstock for bio ethanol production. The fermentation of bio ethanol production was carried out by Saccharomyces cerevisiae in which ethanol produced was measured by gas chromatography. In order to increase its fermentable sugar content, the SLW was treated with dilute acid. Center composite design of response surface methodology (RSM) had been used to optimize the sugar content by varying the parameters involved in the dilute acid pretreatment conditions. These are sulphuric acid concentration (M), temperature (degree Celsius) and seaweed waste concentration (g/ ml). It was obtained that the R 2 value reached 0.97 indicating that the model is acceptable. The three parameters showed p-value less than 0.05 suggesting their significance interactions. The optimization resulted 25 times improvement of reducing sugar concentration. The reducing sugar resulting from the optimized pretreatment was later used as fermentation medium to produce ethanol up to 123.197 mg/ l. (author)

  1. [Effect of Residual Hydrogen Peroxide on Hydrolysis Acidification of Sludge Pretreated by Microwave -H2O2-Alkaline Process].

    Science.gov (United States)

    Jia, Rui-lai; Liu, Ji-bao; Wei, Yuan-song; Cai, Xing

    2015-10-01

    Previous studies have found that in the hydrolysis acidification process, sludge after microwave -H2O2-alkaline (MW-H2O2-OH, pH = 10) pretreatment had an acid production lag due to the residual hydrogen peroxide. In this study, effects of residual hydrogen peroxide after MW-H2O2-OH (pH = 10 or pH = 11) pretreatment on the sludge hydrolysis acidification were investigated through batch experiments. Our results showed that catalase had a higher catalytic efficiency than manganese dioxide for hydrogen peroxide, which could completely degraded hydrogen peroxide within 10 min. During the 8 d of hydrolysis acidification time, both SCOD concentrations and the total VFAs concentrations of four groups were firstly increased and then decreased. The optimized hydrolysis times were 0.5 d for four groups, and the optimized hydrolysis acidification times were 3 d for MW-H2O2-OH (pH = 10) group, MW-H2O2-OH (pH = 10) + catalase group and MW-H2O2-OH (pH = 11) + catalase group. The optimized hydrolysis acidification time for MW-H2O2-OH (pH = 11) group was 4 d. Residual hydrogen peroxide inhibited acid production for sludge after MW-H2O2-OH (pH = 10) pretreatment, resulting in a lag in acidification stage. Compared with MW-H2O2-OH ( pH = 10) pretreatment, MW-H2O2-OH (pH = 11 ) pretreatment released more SCOD by 19.29% and more organic matters, which resulted in the increase of total VFAs production significantly by 84.80% at 5 d of hydrolysis acidification time and MW-H2O2-OH (pH = 11) group could shorten the lag time slightly. Dosing catalase (100 mg x -L(-1)) after the MW-H2O2-OH (pH = 10 or pH = 11) pretreatment not only significantly shortened the lag time (0.5 d) in acidification stage, but also produced more total VFAs by 23.61% and 50.12% in the MW-H2O2-OH (pH = 10) + catalase group and MW-H2O2-OH (pH = 11) + catalase group, compared with MW-H2O2-OH (pH = 10) group at 3d of hydrolysis acidification time. For MW-H2O2-OH (pH = 10) group, MW-H2O2-OH (pH = 10) + catalase group and

  2. Does pretreatment hemoglobin level affect outcome in patients with T1 glottic cancer?

    International Nuclear Information System (INIS)

    Canaday, Daniel J.; Regine, William F.; Mohiuddin, Mohammed; Zollinger, William; Machtay, Mitchell; Lee, Jason; Schultz, Delray; Rosenthal, David I.; Rudoltz, Marc S.

    1997-01-01

    Purpose/Objective: Recent reports have suggested that pretreatment hemoglobin (Hgb) is significantly associated with local control (LC) and overall survival (OS) in patients with T1 and T2 squamous cell carcinoma of the glottic larynx. This study evaluates the association of pretreatment Hgb level and other factors with outcome in patients limited to T1 squamous cell carcinoma of the glottic larynx treated with external beam radiation. Methods: One hundred fifty-eight patients with T1 squamous cell carcinoma of the glottic larynx were analyzed. Median follow-up was 5 years (range 2-22). Median pretreatment Hgb was 14.4 gm/dl (range 8.2-17.2). The following parameters were analyzed for their impact on LC, OS, and disease specific survival (DSS): age, gender, pretreatment Hgb, tumor grade, anterior commissure involvement, field size, total dose, dose per fraction, and overall treatment time. Results: Five year actuarial LC was 84%. Pretreatment Hgb was not a significant predictor for LC when assessed as a continuous variable (p=0.38). LC was 82% for patients with Hgb >13 vs 92% for Hgb ≤ 13 (p=0.13). No other factor was significant for LC. Five year actuarial OS was 74%. On univariate analysis, pretreatment Hgb ≤ 13 gm/dl was a significant factor for poorer OS (78% vs 68%, p=0.004), as were total dose 61 years (p=0.017). On multivariate analysis, only age >61 (p=0.014) and Hgb ≤ 13 (p=0.001) retained significance for OS. Five year actuarial DSS was 92%. Pretreatment Hgb was not a prognostic factor for DSS, nor were any other analyzed factors. Conclusion: Pretreatment Hgb is not a significant prognostic factor for LC in patients with T1 squamous cell carcinoma of the glottic larynx, but it does predict for a poorer OS without affecting DSS. This suggests that patients with lower pretreatment Hgb may have confounding medical problems which detract from their overall survival

  3. Comparison of Ultrasonic and CO2 Laser Pretreatment Methods on Enzyme Digestibility of Corn Stover

    Directory of Open Access Journals (Sweden)

    Li-Li Zuo

    2012-03-01

    Full Text Available To decrease the cost of bioethanol production, biomass recalcitrance needs to be overcome so that the conversion of biomass to bioethanol becomes more efficient. CO2 laser irradiation can disrupt the lignocellulosic physical structure and reduce the average size of fiber. Analyses with Fourier transform infrared spectroscopy, specific surface area, and the microstructure of corn stover were used to elucidate the enhancement mechanism of the pretreatment process by CO2 laser irradiation. The present work demonstrated that the CO2 laser had potential to enhance the bioconversion efficiency of lignocellulosic waste to renewable bioethanol. The saccharification rate of the CO2 laser pretreatment was significantly higher than ultrasonic pretreatment, and reached 27.75% which was 1.34-fold of that of ultrasonic pretreatment. The results showed the impact of CO2 laser pretreatment on corn stover to be more effective than ultrasonic pretreatment.

  4. PROJECT W-551 INTERIM PRETREATMENT SYSTEM TECHNOLOGY SELECTION SUMMARY DECISION REPORT AND RECOMMENDATION

    International Nuclear Information System (INIS)

    CONRAD EA

    2008-01-01

    This report provides the conclusions of the tank farm interim pretreatment technology decision process. It documents the methodology, data, and results of the selection of cross-flow filtration and ion exchange technologies for implementation in project W-551, Interim Pretreatment System. This selection resulted from the evaluation of specific scope criteria using quantitative and qualitative analyses, group workshops, and technical expert personnel

  5. Enhanced fermentable sugar production from kitchen waste using various pretreatments.

    Science.gov (United States)

    Hafid, Halimatun Saadiah; Rahman, Nor'Aini Abdul; Md Shah, Umi Kalsom; Baharudin, Azhari Samsu

    2015-06-01

    The kitchen waste fraction in municipal solid waste contains high organic matter particularly carbohydrate that can contribute to fermentable sugar production for subsequent conversion to bioethanol. This study was carried out to evaluate the influence of single and combination pretreatments of kitchen waste by liquid hot water, mild acid pretreatment of hydrochloric acid (HCl) and sulphuric acid (H2SO4) and enzymatic hydrolysis (glucoamylase). The maximum total fermentable sugar produced after combination pretreatment by 1.5% HCl and glucoamylase consisted of 93.25 g/L glucose, 0.542 g/L sucrose, 0.348 g/L maltose, and 0.321 g/L fructose. The glucose released by the combination pretreatment method was 0.79 g glucose/g KW equivalent to 79% of glucose conversion. The effects of the pre-treatment on kitchen waste indicated that the highest solubilization was 40% by the combination method of 1.5% HCl and glucoamylase. The best combination pre-treatment gave concentrations of lactic acid, acetic acid, and propionic acid of 11.74 g/L, 6.77 g/L, and 1.02 g/L, respectively. The decrease of aliphatic absorbance bands of polysaccharides at 2851 and 2923 cm(-1) and the increase on structures of carbonyl absorbance bands at 1600 cm(-1) reflects the progress of the kitchen waste hydrolysis to fermentable sugars. Overall, 1.5% HCl and glucoamylase treatment was the most profitable process as the minimum selling price of glucose was USD 0.101/g kitchen waste. Therefore, the combination pretreatment method was proposed to enhance the production of fermentable sugar, particularly glucose from kitchen waste as the feedstock for bioethanol production. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Statement of work for architect-engineer services, initial pretreatment module

    International Nuclear Information System (INIS)

    Sowa, K.B.

    1994-01-01

    This Statement of Work describes the Architect-Engineer services to be provided by Raytheon/BNFL in providing a conceptual design (Contract TGW-SVV-063869) for the Initial Pretreatment Module (IPM), Project W-236B, at the Hanford site, Richland, Washington. The IPM Project, a radiochemical process facility, will be designed and constructed for an initial phase of waste pretreatment, which will be for the removal of cesium from supernatant wastes to produce a Low-level waste (LLW) stream to a vitrification facility. The design shall also accommodate side streams of High-Level Waste (HLW) fractions that will be directed to suitable, existing storage tanks where they will be recombined with an additional high-activity waste fraction generated from pretreatment of the tank waste sludges and solids. This combined high-activity waste fraction will be immobilized as glass and disposed in a geological repository

  7. Solubility of Plutonium (IV) Oxalate During Americium/Curium Pretreatment

    International Nuclear Information System (INIS)

    Rudisill, T.S.

    1999-01-01

    Approximately 15,000 L of solution containing isotopes of americium and curium (Am/Cm) will undergo stabilization by vitrification at the Savannah River Site (SRS). Prior to vitrification, an in-tank pretreatment will be used to remove metal impurities from the solution using an oxalate precipitation process. Material balance calculations for this process, based on solubility data in pure nitric acid, predict approximately 80 percent of the plutonium in the solution will be lost to waste. Due to the uncertainty associated with the plutonium losses during processing, solubility experiments were performed to measure the recovery of plutonium during pretreatment and a subsequent precipitation process to prepare a slurry feed for a batch melter. A good estimate of the plutonium content of the glass is required for planning the shipment of the vitrified Am/Cm product to Oak Ridge National Laboratory (ORNL).The plutonium solubility in the oxalate precipitation supernate during pretreatment was 10 mg/mL at 35 degrees C. In two subsequent washes with a 0.25M oxalic acid/0.5M nitric acid solution, the solubility dropped to less than 5 mg/mL. During the precipitation and washing steps, lanthanide fission products in the solution were mostly insoluble. Uranium, and alkali, alkaline earth, and transition metal impurities were soluble as expected. An elemental material balance for plutonium showed that greater than 94 percent of the plutonium was recovered in the dissolved precipitate. The recovery of the lanthanide elements was generally 94 percent or higher except for the more soluble lanthanum. The recovery of soluble metal impurities from the precipitate slurry ranged from 15 to 22 percent. Theoretically, 16 percent of the soluble oxalates should have been present in the dissolved slurry based on the dilution effects and volumes of supernate and wash solutions removed. A trace level material balance showed greater than 97 percent recovery of americium-241 (from the beta dec

  8. Pretreatment techniques for biofuels and biorefineries

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Zhen (ed.) [Chinese Academy of Sciences, Kunming, YN (China). Xishuangbanna Tropical Botonical Garden

    2013-02-01

    The first book focused on pretreatment techniques for biofuels contributed by the world's leading experts. Extensively covers the different types of biomass, various pretreatment approaches and methods that show the subsequent production of biofuels and chemicals. In addition to traditional pretreatment methods, novel techniques are also introduced and discussed. An accessible reference work for students, researchers, academicians and industrialists in biorefineries. This book includes 19 chapters contributed by the world's leading experts on pretreatment methods for biomass. It extensively covers the different types of biomass (e.g. molasses, sugar beet pulp, cheese whey, sugarcane residues, palm waste, vegetable oil, straws, stalks and wood), various pretreatment approaches (e.g. physical, thermal, chemical, physicochemical and biological) and methods that show the subsequent production of biofuels and chemicals such as sugars, ethanol, extracellular polysaccharides, biodiesel, gas and oil. In addition to traditional methods such as steam, hot-water, hydrothermal, diluted-acid, organosolv, ozonolysis, sulfite, milling, fungal and bacterial, microwave, ultrasonic, plasma, torrefaction, pelletization, gasification (including biogas) and liquefaction pretreatments, it also introduces and discusses novel techniques such as nano and solid catalysts, organic electrolyte solutions and ionic liquids. This book offers a review of state-of-the-art research and provides guidance for the future paths of developing pretreatment techniques of biomass for biofuels, especially in the fields of biotechnology, microbiology, chemistry, materials science and engineering. It intends to provide a systematic introduction of pretreatment techniques. It is an accessible reference work for students, researchers, academicians and industrialists in biorefineries.

  9. Changes in feedwater organic matter concentrations based on intake type and pretreatment processes at SWRO facilities, Red Sea, Saudi Arabia

    KAUST Repository

    Dehwah, Abdullah

    2015-03-01

    Transparent exopolymer particles (TEP), natural organic matter, and bacterial concentrations in feedwater are important factors that can lead to membrane biofouling in seawater reverse osmosis (SWRO) systems. Two methods for controlling these concentrations in the feedwater prior to pretreatment have been suggested; use of subsurface intake systems or placement of the intake at a greater depth in the sea. These proposed solutions were tested at two SWRO facilities located along the Red Sea of Saudi Arabia. A shallow well intake system was very effective in reducing the algae and bacterial concentrations and somewhat effective in reducing TEP concentrations. An intake placed at a depth of 9. m below the surface was found to have limited impact on improving water quality compared to a surface intake. The algae and bacteria concentration in the feedwater (deep) was lower compared to the surface seawater, but the overall TEP concentration was higher. Bacteria and TEP measurements made in the pretreatment process train in the plant and after the cartridge filters suggest that regrowth of bacteria is occurring within the cartridge filters.

  10. Changes in feedwater organic matter concentrations based on intake type and pretreatment processes at SWRO facilities, Red Sea, Saudi Arabia

    KAUST Repository

    Dehwah, Abdullah; Li, Sheng; Almashharawi, Samir; Winters, Harvey; Missimer, Thomas M.

    2015-01-01

    Transparent exopolymer particles (TEP), natural organic matter, and bacterial concentrations in feedwater are important factors that can lead to membrane biofouling in seawater reverse osmosis (SWRO) systems. Two methods for controlling these concentrations in the feedwater prior to pretreatment have been suggested; use of subsurface intake systems or placement of the intake at a greater depth in the sea. These proposed solutions were tested at two SWRO facilities located along the Red Sea of Saudi Arabia. A shallow well intake system was very effective in reducing the algae and bacterial concentrations and somewhat effective in reducing TEP concentrations. An intake placed at a depth of 9. m below the surface was found to have limited impact on improving water quality compared to a surface intake. The algae and bacteria concentration in the feedwater (deep) was lower compared to the surface seawater, but the overall TEP concentration was higher. Bacteria and TEP measurements made in the pretreatment process train in the plant and after the cartridge filters suggest that regrowth of bacteria is occurring within the cartridge filters.

  11. Interim data quality objectives for waste pretreatment and vitrification. Revision 1

    International Nuclear Information System (INIS)

    Kupfer, M.J.; Conner, J.M.; Kirkbride, R.A.; Mobley, J.R.

    1994-01-01

    The Tank Waste Remediation System (TWRS) is responsible for storing, processing, and immobilizing the Hanford Site tank wastes. Characterization information on the tank wastes is needed so that safety concerns can be addressed, and retrieval, pretreatment, and immobilization processes can be designed, permitted, and implemented. This document describes the near-term tank waste sampling and characterization needs of the Pretreatment, High-Level Waste (HLW) Disposal, and Low-Level Waste (LLW) Disposal Programs to support the TWRS disposal mission. The final DQO (Data Quality Objective) will define specific waste tanks to be sampled, sample timing requirements, an appropriate analytical scheme, and a list of required analytes. This interim DQO, however, focuses primarily on the required analytes since the tanks to be sampled in FY 1994 and early FY 1995 are being driven most heavily by other considerations, particularly safety. The major objective of this Interim DQO is to provide guidance for tank waste characterization requirements for samples taken before completion of the final DQO. The characterization data needs defined herein will support the final DQO to help perform the following: Support the TWRS technical strategy by identification of the chemical and physical composition of the waste in the tanks and Guide development efforts to define waste pretreatment processes, which will in turn define HLW and LLW feed to vitrification processes

  12. Enhanced Dissolution of Platinum Group Metals Using Electroless Iron Deposition Pretreatment

    Science.gov (United States)

    Taninouchi, Yu-ki; Okabe, Toru H.

    2017-12-01

    In order to develop a new method for efficiently recovering platinum group metals (PGMs) from catalyst scraps, the authors investigated an efficient dissolution process where the material was pretreated by electroless Fe deposition. When Rh-loaded alumina powder was kept in aqua regia at 313 K (40 °C) for 30 to 60 minutes, the Rh hardly dissolved. Meanwhile, after electroless Fe plating using a bath containing sodium borohydride and potassium sodium tartrate as the reducing and complexing agents, respectively, approximately 60 pct of Rh was extracted by aqua regia at 313 K (40 °C) after 30 minutes. Furthermore, when heat treatment was performed at 1200 K (927 °C) for 60 minutes in vacuum after electroless plating, the extraction of Rh approached 100 pct for the same leaching conditions. The authors also confirmed that the Fe deposition pretreatment enhanced the dissolution of Pt and Pd. These results indicate that an effective and environmentally friendly process for the separation and extraction of PGMs from catalyst scraps can be developed utilizing this Fe deposition pretreatment.

  13. Production of brown algae pyrolysis oils for liquid biofuels depending on the chemical pretreatment methods

    International Nuclear Information System (INIS)

    Choi, Joonhyuk; Choi, Jae-Wook; Suh, Dong Jin; Ha, Jeong-Myeong; Hwang, Ji Won; Jung, Hyun Wook; Lee, Kwan-Young; Woo, Hee-Chul

    2014-01-01

    Highlights: • Pyrolysis of Saccharina japonica, brown algae to produce hydrocarbons. • Sulfuric acid pretreatment of macroalgae to remove inorganic elements. • CaCl 2 treatment of macroalgae to remove valuable fucoidan. • Sulfuric acid pretreatment suppressed the formation of large biochar chunks. • The pretreatment methods allowed the continuous operation of pyrolysis. - Abstract: Based on observations of rapidly growing biochar in fluidization beds, kelp (Saccharina japonica), a species of brown algae, was pretreated for the efficient operation of pyrolysis processes to produce pyrolysis oils. The removal of catalytically active inorganic minerals and the softening of polymeric seaweed structures were performed by means of chemical treatments, including a CaCl 2 treatment to isolate valuable and sticky fucoidan and a sulfuric acid treatment to remove catalytically active minerals. The sulfuric acid pretreatment significantly reduced the inorganic elements but did not significantly affect the properties of the pyrolysis oil compared to the non-treated kelp pyrolysis oil. Whereas the non-treated kelp produced significantly large chunks of biochar, which hindered the continuous operation of pyrolysis, the kelp treated with sulfuric acid did not produce aggregated large particles of biochar, thereby offering a means of developing reliable continuous pyrolysis processes

  14. Effect of Mucuna pruriens Seed Extract Pretreatment on the Responses of Spontaneously Beating Rat Atria and Aortic Ring to Naja sputatrix (Javan Spitting Cobra) Venom

    Science.gov (United States)

    Fung, Shin Yee; Tan, Nget Hong; Sim, Si Mui; Aguiyi, John C.

    2012-01-01

    Mucuna pruriens Linn. (velvet bean) has been used by native Nigerians as a prophylactic for snakebite. Rats pretreated with M. pruriens seed extract (MPE) have been shown to protect against the lethal and cardiovascular depressant effects of Naja sputatrix (Javan spitting cobra) venoms, and the protective effect involved immunological neutralization of the venom toxins. To investigate further the mechanism of the protective effect of MPE pretreatment against cobra venom toxicity, the actions of Naja sputatrix venom on spontaneously beating rat atria and aortic rings isolated from both MPE pretreated and untreated rats were studied. Our results showed that the MPE pretreatment conferred protection against cobra venom-induced depression of atrial contractility and atrial rate in the isolated atrial preparations, but it had no effect on the venom-induced contractile response of aortic ring preparation. These observations suggested that the protective effect of MPE pretreatment against cobra venom toxicity involves a direct protective action of MPE on the heart function, in addition to the known immunological neutralization mechanism, and that the protective effect does not involve action on blood vessel contraction. The results also suggest that M. pruriens seed may contain novel cardioprotective agent with potential therapeutic value. PMID:21785646

  15. Effect of advanced oxidation processes (AOP's) on the toxicity of municipal landfill leachates

    Energy Technology Data Exchange (ETDEWEB)

    Slomczynska, B.; Slomczynski, T. [Inst. of Environmental Engineering Systems, Warsaw Univ. of Technology, Warsaw (Poland); Wasowski, J. [Inst. of Water Supply and Hydraulic Construction, Warsaw Univ. of Technology, Warsaw (Poland)

    2003-07-01

    The aim of present study was to assess the effect of AOP's (oxidation ozone and peroxide/ozone) on the toxicity of leachates from municipal landfill for Warsaw, Poland, using battery of tests. Advanced oxidation processes used to pre-treat leachates were carried out in laboratory conditions after their coagulation with the use of FeCl{sub 3}. The effects of the pre-treatment of leachates using the method of coagulation with FeCl{sub 3} depended on the concentration of organic compounds and with optimal conditions of the process ranged from 40 to 70%. Further pre-treatment of the leachates after coagulation, involving the use of oxidation with O{sub 3} and H{sub 2}O{sub 2}/O{sub 3}, did not caused significant decrease of leachate toxicity. The data of this study demonstrated the usefulness of the battery of tests using Daphnia magna, Artemia franciscana, Scenedesmus quadricauda and Vibrio fischeri for the toxicity evaluation of raw and pre-treated leachates. (orig.)

  16. The Use of Clay-Polymer Nanocomposites in Wastewater Pretreatment

    Science.gov (United States)

    Rytwo, Giora

    2012-01-01

    Some agricultural effluents are unsuitable for discharge into standard sewage-treatment plants: their pretreatment is necessary to avoid clogging of the filtering devices by colloidal matter. The colloidal stability of the effluents is mainly due to mutual repulsive forces that keep charged particles in suspension. Pretreatment processes are based on two separate stages: (a) neutralization of the charges (“coagulation”) and (b) bridging between several small particles to form larger aggregates that sink, leaving clarified effluent (“flocculation”). The consequent destabilization of the colloidal suspension lowers total suspended solids (TSSs), turbidity, and other environmental quality parameters, making the treatments that follow more efficient. Clay-based materials have been widely used for effluent pretreatment and pollutant removal. This study presents the use of nanocomposites, comprised of an anchoring particle and a polymer, as “coagoflocculants” for the efficient and rapid reduction of TSS and turbidity in wastewater with a high organic load. The use of such particles combines the advantages of coagulant and flocculant by neutralizing the charge of the suspended particles while bridging between them and anchoring them to a denser particle (the clay mineral), enhancing their precipitation. Very rapid and efficient pretreatment is achieved in one single treatment step. PMID:22454607

  17. Involving IDPs in the Darfur peace process

    Directory of Open Access Journals (Sweden)

    David Lanz

    2008-04-01

    Full Text Available The UN estimates that there are 2.4 millionIDPs in Darfur –over one third of the totalpopulation. There can be no meaningfulpeace process without their involvement.Giving IDPs a formal seat in official peacenegotiations is problematic but there areother ways to ensure their participation.

  18. Pre-treatment of Used-Cooking Oil as Feed Stocks of Biodiesel Production by Using Activated Carbon and Clay Minerals

    Directory of Open Access Journals (Sweden)

    Rudy Syah Putra

    2014-02-01

    Full Text Available Many low-cost feedstock i.e. used-cooking oil (UCO for the production of biodiesel fuel (BDF has contained a large amount of water and high proportion of free fatty acids (FFAs. Therefore, a pre-treatment process to reduce the water content (<0.1 wt.% and FFAs (<2.0 wt.% were necessary in order to avoid an undesirable side reactions, such as saponification, which could lead to serious problem of product separation and low fatty acid methyl ester (FAME yield. . In this study, a pre-treatment process of used cooking oil as a feedstock for the production of BDF by using various adsorbents such as Activated Carbon (AC and various clay minerals, for example Smectite (S, Bentonite (B, Kaolinite (K, and Powdered Earthenware (PE were evaluated. The oil obtained from pre-treatment was compared with oil without pre-treatment process. In this study, we reported a basic difference in material ability to the oil, depending on the adsorption condition with respect to the physico-chemical parameters, e.g. refractive index (R, density (ρ, FFAs, and water content (W. The results showed that the water content and FFAs in the oil has decreased when using AC as an adsorbent compared with clay minerals. However, the refractive index of oil has similar with the oil without pre-treatment process as well; meanwhile, the density of oil has increased after the pre-treatment process by using clay minerals.

  19. Fast and efficient nanoshear hybrid alkaline pretreatment of corn stover for biofuel and materials production

    International Nuclear Information System (INIS)

    Wang, Wei; Ji, Shaowen; Lee, Ilsoon

    2013-01-01

    We report a fast and efficient nano-scale shear hybrid alkaline (NSHA) pretreatment method of lignocellulosic biomass. In this work, corn stover was pretreated in a modified Taylor–Couette reactor with alkali (sodium hydroxide) at room temperature for two minutes. Up to 82% of high cellulose content in the remaining solids was achieved with the novel NSHA pretreatment process. Compared with untreated corn stover, an approximately 4-fold increase in enzymatic cellulose conversion and a 5-fold increase in hemicellulose conversion were achieved. Compositional analysis proved significant removals of both lignin and hemicellulose after the NSHA pretreatment. SEM images revealed that the synergistic effect of NSHA pretreatment caused the severe disruption of biomass structure and exposure of cellulose microfibril aggregates in NSHA pretreated corn stover. Highlights: ► A fast nanoshear hybrid alkaline (NSHA) pretreatment method is reported. ► A modified Taylor–Couette reactor was applied. ► The retention time of the NSHA method is only 2 min. ► A 100% conversion of glucan was achieved in one day. ► NSHA greatly removed both lignin and xylan

  20. Efficient sugar release by acetic acid ethanol-based organosolv pretreatment and enzymatic saccharification.

    Science.gov (United States)

    Zhang, Hongdan; Wu, Shubin

    2014-12-03

    Acetic acid ethanol-based organosolv pretreatment of sugar cane bagasse was performed to enhance enzymatic hydrolysis. The effect of different parameters (including temperature, reaction time, solvent concentration, and acid catalyst dose) on pretreatment prehydrolyzate and subsequent enzymatic digestibility was determined. During the pretreatment process, 11.83 g of xylose based on 100 g of raw material could be obtained. After the ethanol-based pretreatment, the enzymatic hydrolysis was enhanced and the highest glucose yield of 40.99 g based on 100 g of raw material could be obtained, representing 93.8% of glucose in sugar cane bagasse. The maximum total sugar yields occurred at 190 °C, 45 min, 60:40 ethanol/water, and 5% dosage of acetic acid, reaching 58.36 g (including 17.69 g of xylose and 40.67 g of glucose) based on 100 g of raw material, representing 85.4% of total sugars in raw material. Furthermore, characterization of the pretreated sugar cane bagasse using X-ray diffraction and scanning electron microscopy analyses were also developed. The results suggested that ethanol-based organosolv pretreatment could enhance enzymatic digestibilities because of the delignification and removal of xylan.

  1. Same-vessel enzymatic saccharification and fermentation of organosolv/H2O2 pretreated oil palm (Elaeis guineensis Jacq.) fronds for bioethanol production: Optimization of process parameters

    International Nuclear Information System (INIS)

    Ofori-Boateng, Cynthia; Lee, Keat Teong

    2014-01-01

    Highlights: • Same vessel enzymatic saccharification and fermentation (SVSF) of pretreated OPFs. • Optimum conditions:37 °C, 8.0% solid loading, 14.0 g/l yeast concentration, pH 5.3. • Optimum bioethanol concentration and yield of 21.96 g/l and 84.65% respectively. • Organosolv/H 2 O 2 pretreatment of OPFs improved SVSF yield at high solid loading. - Abstract: Based on optimized pretreatment process, oil palm fronds (OPFs) were sequentially pretreated with 1.4% (w/v) aq. NaOH in 80% ethanol with ultrasound assistance (at 75 °C for 30 min) and 3% (v/v) aq. H 2 O 2 . Using the Box–Behnken design (BBD) of response surface methodology (RSM), bioethanol production from the sono-assisted organosolv/H 2 O 2 OPFs were optimized using same-vessel enzymatic saccharification and fermentation (SVSF) where both the hydrolysis and fermentation processes were carried out in one vessel simultaneously. Throughout the SVSF process, the incubation time and enzyme loading were kept at 72 h and 15 filter paper unit (FPU)/g substrate respectively. The other SVSF parameters which affect bioethanol yield such as temperature (X 1 : 30–50 °C), solid loading (X 2 : 5.0–10.0% w/v), yeast concentration (X 3 : 5.0–20 g/l) and pH (X 4 : 4.0–7.0) were optimized. Well fitted regression equations (R 2 > 0.97) obtained were able to predict reliable optimum bioethanol concentration and yield. The predicted optimum bioethanol concentration (i.e., 20.61 g/l) and yield (i.e., 84.60%) were attained at 36.94 °C (∼37 °C), 7.57% w/v solid loading (∼8.0% w/v), 13.97 g/l yeast concentration (∼14.0 g/l) and pH of 5.29 (∼5.30). Validated results indicated a maximum ethanol concentration and yield of 21.96 g/l and 84.65% respectively, which were closer to the predicted optimum responses. Using the optimum conditions, the highest bioethanol productivity of 0.76 g/l/h was observed at 12 h of SVSF process

  2. Surface pretreatment of plastics with an atmospheric pressure plasma jet - Influence of generator power and kinematics

    International Nuclear Information System (INIS)

    Moritzer, E.; Leister, C.

    2014-01-01

    The industrial use of atmospheric pressure plasmas in the plastics processing industry has increased significantly in recent years. Users of this treatment process have the possibility to influence the target values (e.g. bond strength or surface energy) with the help of kinematic and electrical parameters. Until now, systematic procedures have been used with which the parameters can be adapted to the process or product requirements but only by very time-consuming methods. For this reason, the relationship between influencing values and target values will be examined based on the example of a pretreatment in the bonding process with the help of statistical experimental design. Because of the large number of parameters involved, the analysis is restricted to the kinematic and electrical parameters. In the experimental tests, the following factors are taken as parameters: gap between nozzle and substrate, treatment velocity (kinematic data), voltage and duty cycle (electrical data). The statistical evaluation shows significant relationships between the parameters and surface energy in the case of polypropylene. An increase in the voltage and duty cycle increases the polar proportion of the surface energy, while a larger gap and higher velocity leads to lower energy levels. The bond strength of the overlapping bond is also significantly influenced by the voltage, velocity and gap. The direction of their effects is identical with those of the surface energy. In addition to the kinematic influences of the motion of an atmospheric pressure plasma jet, it is therefore especially important that the parameters for the plasma production are taken into account when designing the pretreatment processes

  3. Optimization study on the hydrogen peroxide pretreatment and production of bioethanol from seaweed Ulva prolifera biomass.

    Science.gov (United States)

    Li, Yinping; Cui, Jiefen; Zhang, Gaoli; Liu, Zhengkun; Guan, Huashi; Hwang, Hueymin; Aker, Winfred G; Wang, Peng

    2016-08-01

    The seaweed Ulva prolifera, distributed in inter-tidal zones worldwide, contains a large percentage of cellulosic materials. The technical feasibility of using U. prolifera residue (UPR) obtained after extraction of polysaccharides as a renewable energy resource was investigated. An environment-friendly and economical pretreatment process was conducted using hydrogen peroxide. The hydrogen peroxide pretreatment improved the efficiency of enzymatic hydrolysis. The resulting yield of reducing sugar reached a maximum of 0.42g/g UPR under the optimal pretreatment condition (hydrogen peroxide 0.2%, 50°C, pH 4.0, 12h). The rate of conversion of reducing sugar in the concentrated hydrolysates to bioethanol reached 31.4% by Saccharomyces cerevisiae fermentation, which corresponds to 61.7% of the theoretical maximum yield. Compared with other reported traditional processes on Ulva biomass, the reducing sugar and bioethanol yield are substantially higher. Thus, hydrogen peroxide pretreatment is an effective enhancement of the process of bioethanol production from the seaweed U. prolifera. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Technological pretreatment of the synchysite non-oxidized ore

    Science.gov (United States)

    Munkhtsetseg, B.; Burmaa, G.

    2013-06-01

    Mongolia has rich deposits of rare, precious, and poly-metallic ores. Nowadays, it is important to research separation of rare earth elements oxides concentrates from the ores, analyze their unique physical chemical characteristics, and purified it. Our investigation on raw materials focuses on rare earth non-oxidized ores. Main mineral in this rock sample is Synchysite (LnCa(CO3)2F. We did technological and thermal pretreatment: direct sulphurization (H2SO4), sulphurization with subsequent roasting (800°C+H2SO4), sulphurization prior to roasting (H2SO4+650°C). Sulphurization method based on dissolution of rare earth mineral into sulfuric acid (93%) according to the reaction. The amount of rare earth element oxides is almost 10 times greater (29.16%) after direct sulphurization process, almost 8 times greater (21.14%) after sulphurization with subsequent roasting, and almost 20 times greater (44.62%) after sulphurization prior to roasting process. After those technological pretreatment raw material's micro elements Thorium and Uranium contents are reduced as follows: H2SO4>800°C+H2SO4>H2SO4+650°C. These results show that cerium group rare earth elements have very good solubility in water at +2°C temperature and decreasing micro elements content uranium and thorium good pretreatment condition is prior to roasting (H2SO4+650°C) of synchysite non-oxidized ore.

  5. Development of over-production strain of saccharification enzyme and biomass pretreatment by proton beam irradiation

    International Nuclear Information System (INIS)

    Kim, S. O.; Lee, J. Y.; Song, Y. S.; Shin, H. S.

    2009-04-01

    - The first year : Pre-treatment of biomass by proton beam irradiation and characterization of the pretreated biomass by IR and SEM - The second year : Strain development by proton beam irradiation for the production of cellulase and hemicellulase - The third year : Optimization of Saccharification process by cellulase and hemicellulase

  6. Facile preparation of nitrogen-doped porous carbon from waste tobacco by a simple pre-treatment process and their application in electrochemical capacitor and CO{sub 2} capture

    Energy Technology Data Exchange (ETDEWEB)

    Sha, Yunfei; Lou, Jiaying [Technical Center, Shanghai Tobacco Group Co., Ltd., Shanghai 200082 (China); Bai, Shizhe [Department of Chemistry, Fudan University, Shanghai 200433 (China); Wu, Da, E-mail: wud@sh.tobacco.com.cn [Technical Center, Shanghai Tobacco Group Co., Ltd., Shanghai 200082 (China); Liu, Baizhan [Technical Center, Shanghai Tobacco Group Co., Ltd., Shanghai 200082 (China); Ling, Yun, E-mail: yunling@fudan.edu.cn [Department of Chemistry, Fudan University, Shanghai 200433 (China)

    2015-04-15

    Highlights: • A pre-treatment process is used to prepared N-doped carbon from waste biomass. • Waste tobaccos, which are limited for the disposal, are used as the raw materials. • The product shows a specific surface area and nitrogen content. • Its electrochemical performance is better than commercial activated carbon. • Its CO{sub 2} sorption performance is also better than commercial activated carbon. - Abstract: Preparing nitrogen-doped porous carbons directly from waste biomass has received considerable interest for the purpose of realizing the atomic economy. In this study, N-doped porous carbons have been successfully prepared from waste tobaccos (WT) by a simple pre-treatment process. The sample calcinated at 700 °C (WT-700) shows a micro/meso-porous structures with a BET surface area of 1104 m{sup 2} g{sup −1} and a nitrogen content of ca. 19.08 wt.% (EDS). Performance studies demonstrate that WT-700 displays 170 F g{sup −1} electrocapacitivity at a current density of 0.5 A g{sup −1} (in 6 M KOH), and a CO{sub 2} capacity of 3.6 mmol g{sup −1} at 0 °C and 1 bar, and a selectivity of ca. 32 for CO{sub 2} over N{sub 2} at 25 °C. Our studies indicate that it is feasible to prepare N-enriched porous carbons from waste natural crops by a pre-treatment process for potential industrial application.

  7. Sugarcane bagasse pretreatment using three imidazolium-based ionic liquids; mass balances and enzyme kinetics

    Directory of Open Access Journals (Sweden)

    Karatzos Sergios

    2012-08-01

    Full Text Available Abstract Background Effective pretreatment is key to achieving high enzymatic saccharification efficiency in processing lignocellulosic biomass to fermentable sugars, biofuels and value-added products. Ionic liquids (ILs, still relatively new class of solvents, are attractive for biomass pretreatment because some demonstrate the rare ability to dissolve all components of lignocellulosic biomass including highly ordered (crystalline cellulose. In the present study, three ILs, 1-butyl-3-methylimidazolium chloride ([C4mim]Cl, 1-ethyl-3-methylimidazolium chloride ([C2mim]Cl, 1-ethyl-3-methylimidazolium acetate ([C2mim]OAc are used to dissolve/pretreat and fractionate sugarcane bagasse. In these IL-based pretreatments the biomass is completely or partially dissolved in ILs at temperatures greater than 130°C and then precipitated by the addition of an antisolvent to the IL biomass mixture. For the first time mass balances of IL-based pretreatments are reported. Such mass balances, along with kinetics data, can be used in process modelling and design. Results Lignin removals of 10% mass of lignin in bagasse with [C4mim]Cl, 50% mass with [C2mim]Cl and 60% mass with [C2mim]OAc, are achieved by limiting the amount of water added as antisolvent to 0.5 water:IL mass ratio thus minimising lignin precipitation. Enzyme saccharification (24 h, 15FPU yields (% cellulose mass in starting bagasse from the recovered solids rank as: [C2mim]OAc(83% > >[C2mim]Cl(53% = [C4mim]Cl(53%. Composition of [C2mim]OAc-treated solids such as low lignin, low acetyl group content and preservation of arabinosyl groups are characteristic of aqueous alkali pretreatments while those of chloride IL-treated solids resemble aqueous acid pretreatments. All ILs are fully recovered after use (100% mass as determined by ion chromatography. Conclusions In all three ILs regulated addition of water as an antisolvent effected a polysaccharide enriched precipitate since some of the lignin

  8. Surface pre-treatment for barrier coatings on polyethylene terephthalate

    Science.gov (United States)

    Bahre, H.; Bahroun, K.; Behm, H.; Steves, S.; Awakowicz, P.; Böke, M.; Hopmann, Ch; Winter, J.

    2013-02-01

    Polymers have favourable properties such as light weight, flexibility and transparency. Consequently, this makes them suitable for food packaging, organic light-emitting diodes and flexible solar cells. Nonetheless, raw plastics do not possess sufficient barrier functionality against oxygen and water vapour, which is of paramount importance for most applications. A widespread solution is to deposit thin silicon oxide layers using plasma processes. However, silicon oxide layers do not always fulfil the requirements concerning adhesion and barrier performance when deposited on films. Thus, plasma pre-treatment is often necessary. To analyse the influence of a plasma-based pre-treatment on barrier performance, different plasma pre-treatments on three reactor setups were applied to a very smooth polyethylene terephthalate film before depositing a silicon oxide barrier layer. In this paper, the influence of oxygen and argon plasma pre-treatments towards the barrier performance is discussed examining the chemical and topological change of the film. It was observed that a short one-to-ten-second plasma treatment can reduce the oxygen transmission rate by a factor of five. The surface chemistry and the surface topography change significantly for these short treatment times, leading to an increased surface energy. The surface roughness rises slowly due to the development of small spots in the nanometre range. For very long treatment times, surface roughness of the order of the barrier layer's thickness results in a complete loss of barrier properties. During plasma pre-treatment, the trade-off between surface activation and roughening of the surface has to be carefully considered.

  9. Surface pre-treatment for barrier coatings on polyethylene terephthalate

    International Nuclear Information System (INIS)

    Bahre, H; Böke, M; Winter, J; Bahroun, K; Behm, H; Hopmann, Ch; Steves, S; Awakowicz, P

    2013-01-01

    Polymers have favourable properties such as light weight, flexibility and transparency. Consequently, this makes them suitable for food packaging, organic light-emitting diodes and flexible solar cells. Nonetheless, raw plastics do not possess sufficient barrier functionality against oxygen and water vapour, which is of paramount importance for most applications. A widespread solution is to deposit thin silicon oxide layers using plasma processes. However, silicon oxide layers do not always fulfil the requirements concerning adhesion and barrier performance when deposited on films. Thus, plasma pre-treatment is often necessary. To analyse the influence of a plasma-based pre-treatment on barrier performance, different plasma pre-treatments on three reactor setups were applied to a very smooth polyethylene terephthalate film before depositing a silicon oxide barrier layer. In this paper, the influence of oxygen and argon plasma pre-treatments towards the barrier performance is discussed examining the chemical and topological change of the film. It was observed that a short one-to-ten-second plasma treatment can reduce the oxygen transmission rate by a factor of five. The surface chemistry and the surface topography change significantly for these short treatment times, leading to an increased surface energy. The surface roughness rises slowly due to the development of small spots in the nanometre range. For very long treatment times, surface roughness of the order of the barrier layer's thickness results in a complete loss of barrier properties. During plasma pre-treatment, the trade-off between surface activation and roughening of the surface has to be carefully considered. (paper)

  10. 40 CFR 407.14 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for existing sources. 407.14 Section 407.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE...

  11. 40 CFR 407.34 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for existing sources. 407.34 Section 407.34 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE...

  12. 40 CFR 407.24 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for existing sources. 407.24 Section 407.24 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE...

  13. Beam irradiation pretreatment on enzymatic hydrolysis of biomass

    International Nuclear Information System (INIS)

    Yoo, Hah Young; Choi, Han Suk; Yang, Soo Jeong; Lee, Ja Hyun; Kim, Sung Bong; Jung, Da Un; Kim, Seung Wook

    2013-01-01

    As a renewable energy resource, lignocellulosic biomass has become great attention these days. Miscanthus is considered as one of the best feed stock for sugar production due to its high carbohydrate conversion, more efficient pretreatment process was necessary for removal of enzymatic hydrolysis barriers. In this study, electron beam irradiation pretreatment was utilized to Miscanthus straw for the enhancement of sugar conversion. The prepared samples were exposed 20 ∼ 500 kGy of doses and 5 ∼ 100 kGy of dose rate under 1 MeV of energy. Optimum irradiation conditions were 300 kGy of doses, 10 kGy of doses rate and 7.4 mA of current. Finally, compared with untreated Miscanthus, the glucose conversion was 2 fold increased under optimal conditions

  14. Colour of flax fibres in regard to different pretreatment and dyeing processes

    OpenAIRE

    Fakin, Darinka; Ojstršek, Alenka

    2012-01-01

    The main objective of this work was to compare the colour of different pretreated (alkaline, acidic and enzymatic) and dyed (conventional and ultrasonic-assisted) flax fibres, to establish the impact of various parameters on dyeing kinetics. Flax fibres were dyed using two direct dyes of different chemical structures and molecular mass. Diffusion profiles were established by the application of Fick's Law and dyeing behaviour was studied by means of online spectrophotometry. Finally, the dyed ...

  15. Combinatorial pretreatment and fermentation optimization enabled a record yield on lignin bioconversion.

    Science.gov (United States)

    Liu, Zhi-Hua; Xie, Shangxian; Lin, Furong; Jin, Mingjie; Yuan, Joshua S

    2018-01-01

    Lignin valorization has recently been considered to be an essential process for sustainable and cost-effective biorefineries. Lignin represents a potential new feedstock for value-added products. Oleaginous bacteria such as Rhodococcus opacus can produce intracellular lipids from biodegradation of aromatic substrates. These lipids can be used for biofuel production, which can potentially replace petroleum-derived chemicals. However, the low reactivity of lignin produced from pretreatment and the underdeveloped fermentation technology hindered lignin bioconversion to lipids. In this study, combinatorial pretreatment with an optimized fermentation strategy was evaluated to improve lignin valorization into lipids using R. opacus PD630. As opposed to single pretreatment, combinatorial pretreatment produced a 12.8-75.6% higher lipid concentration in fermentation using lignin as the carbon source. Gas chromatography-mass spectrometry analysis showed that combinatorial pretreatment released more aromatic monomers, which could be more readily utilized by lignin-degrading strains. Three detoxification strategies were used to remove potential inhibitors produced from pretreatment. After heating detoxification of the lignin stream, the lipid concentration further increased by 2.9-9.7%. Different fermentation strategies were evaluated in scale-up lipid fermentation using a 2.0-l fermenter. With laccase treatment of the lignin stream produced from combinatorial pretreatment, the highest cell dry weight and lipid concentration were 10.1 and 1.83 g/l, respectively, in fed-batch fermentation, with a total soluble substrate concentration of 40 g/l. The improvement of the lipid fermentation performance may have resulted from lignin depolymerization by the combinatorial pretreatment and laccase treatment, reduced inhibition effects by fed-batch fermentation, adequate oxygen supply, and an accurate pH control in the fermenter. Overall, these results demonstrate that combinatorial

  16. Improvement in shelf life of minimally processed cilantro leaves through integration of kinetin pretreatment and packaging interventions: Studies on microbial population dynamics, biochemical characteristics and flavour retention.

    Science.gov (United States)

    Ranjitha, K; Shivashankara, K S; Sudhakar Rao, D V; Oberoi, Harinder Singh; Roy, T K; Bharathamma, H

    2017-04-15

    Effect of integrating optimized combination of pretreatment with packaging on shelf life of minimally processed cilantro leaves (MPCL) was appraised through analysis of their sensory attributes, biochemical characteristics, microbial population and flavour profile during storage. Minimally pretreated cilantro leaves pretreated with 50ppm kinetin and packed in 25μ polypropylene bags showed a shelf life of 21days. Optimized combination helped in efficiently maintaining sensory parameters, flavour profile, and retention of antioxidants in MPCL until 21days. Studies conducted on the effect of optimized combination on microbial population and flavour profile revealed that among different microorganisms, pectinolysers had a significant effect on spoilage of MPCL and their population of ⩽3.59logcfu/g was found to be acceptable. Principal component analysis of headspace volatiles revealed that (E)-2-undecenal, (E)-2-hexadecenal, (E)-2-tetradecenal & (E)-2-tetradecen-1-ol in stored samples clustered with fresh samples and therefore, could be considered as freshness indicators for MPCL. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Waste Separations and Pretreatment Workshop report

    International Nuclear Information System (INIS)

    Cruse, J.M.; Harrington, R.A.; Quadrel, M.J.

    1994-01-01

    This document provides the minutes from the Waste Separations and Pretreatment Workshop sponsored by the Underground Storage Tank-Integrated Demonstration in Salt Lake City, Utah, February 3--5, 1993. The Efficient Separations and Processing-Integrated Program and the Hanford Site Tank Waste Remediation System were joint participants. This document provides the detailed minutes, including responses to questions asked, an attendance list, reproductions of the workshop presentations, and a revised chart showing technology development activities

  18. THERMO-MECHANICAL PULPING AS A PRETREATMENT FOR AGRICULTURAL BIOMASS FOR BIOCHEMICAL CONVERSION

    Directory of Open Access Journals (Sweden)

    Ronalds W. Gonzalez

    2011-03-01

    Full Text Available The use of thermo-mechanical pulping (TMP, an existing and well known technology in the pulp and paper industry, is proposed as a potential pretreatment pathway of agriculture biomass for monomeric sugar production in preparation for further fermentation into alcohol species. Three agricultural biomass types, corn stover, wheat straw, and sweet sorghum bagasse, were pretreated in a TMP unit under two temperature conditions, 160 ºC and 170 ºC, and hydrolyzed using cellulase at 5, 10, and 20 FPU/g OD biomass. Wheat straw biomass was further pretreated at different conditions including: i soaking with acetic acid, ii longer steaming residence time (15 and 30 min, and iii refined at lower disk gap (0.0508 and 0.1524 mm. Preliminary results showed that carbohydrate conversion increased from 25% to 40% when the TMP temperature was increased from 160 to 170 ºC. Carbohydrate conversion was relatively similar for the three biomasses under the same pretreatment conditions and enzyme loading. Acetic acid soaking and refining at a reduce disk gap increases carbohydrate conversion. Further studies within this technological field to identify optimum process and TMP conditions for pretreatment are suggested.

  19. Combined electrical-alkali pretreatment to increase the anaerobic hydrolysis rate of waste activated sludge during anaerobic digestion

    International Nuclear Information System (INIS)

    Zhen, Guangyin; Lu, Xueqin; Li, Yu-You; Zhao, Youcai

    2014-01-01

    Highlights: • Combined electrical-alkali pretreatment for improving sludge anaerobic digestion was proposed. • Combined process enhanced the cell lysis, biopolymers releases, and thus sludge disintegration. • Increased solubilization of sludge increased the anaerobic hydrolysis rate. • Increased solubilization does not always induce an improved anaerobic digestion efficiency. - Abstract: Pretreatment can be used prior to anaerobic digestion to improve the efficiency of waste activated sludge (WAS) digestion. In this study, electrolysis and a commonly used pretreatment method of alkaline (NaOH) solubilization were integrated as a pretreatment method for promoting WAS anaerobic digestion. Pretreatment effectiveness of combined process were investigated in terms of disintegration degree (DD SCOD ), suspended solids (TSS and VSS) removals, the releases of protein (PN) and polysaccharide (PS), and subsequent anaerobic digestion as well as dewaterability after digestion. Electrolysis was able to crack the microbial cells trapped in sludge gels and release the biopolymers (PN and PS) due to the cooperation of alkaline solubilization, enhancing the sludge floc disintegration/solubilization, which was confirmed by scanning electron microscopy (SEM) analysis. Biochemical methane potential (BMP) assays showed the highest methane yield was achieved with 5 V plus pH 9.2 pretreatment with up to 20.3% improvement over the non-pretreated sludge after 42 days of mesophilic operation. In contrast, no discernible improvements on anaerobic degradability were observed for the rest of pretreated sludges, probably due to the overmuch leakage of refractory soluble organics, partial chemical mineralization of solubilized compounds and sodium inhibition. The statistical analysis further indicated that increased solubilization induced by electrical-alkali pretreatment increased the first-order anaerobic hydrolysis rate (k hyd ), but had no, or very slight enhancement on WAS ultimate

  20. Lyophilization: a useful approach to the automation of analytical processes?

    OpenAIRE

    de Castro, M. D. Luque; Izquierdo, A.

    1990-01-01

    An overview of the state-of-the-art in the use of lyophilization for the pretreatment of samples and standards prior to their storage and/or preconcentration is presented. The different analytical applications of this process are dealt with according to the type of material (reagent, standard, samples) and matrix involved.

  1. 40 CFR 407.26 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 407.26 Section 407.26 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE CATEGORY Apple...

  2. 40 CFR 407.16 - Pretreatment standards for new sources.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 407.16 Section 407.16 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CANNED AND PRESERVED FRUITS AND VEGETABLES PROCESSING POINT SOURCE CATEGORY Apple...

  3. Pretreatment method for radioactive iodine-containing liquid wastes and pretreatment device

    International Nuclear Information System (INIS)

    Wakaida, Yasuo.

    1996-01-01

    Heretofore, radioactive iodine-containing liquid wastes have been discharged directly to a storing and decaying storage vessel to conduct a water draining treatment. In the present invention, the radioactive iodine-containing liquid wastes to be discharged are not discharged to the storage vessel directly but injected to a filling tank, as a pretreatment, to distinguish whether proteins are mixed in the liquid wastes or not. When proteins are mixed, miscellaneous materials such as proteins are recovered and removed by a protein processing system. When proteins are not mixed, radioactive iodine is recovered and removed directly by an iodine processing system. With such procedures, water draining treatment in the storing and decaying storage vessel is mitigated, and even when the amount of the radioactive iodine-containing liquid wastes is increased, the existent maintaining and decaying storage vessel can be used as it is. Accordingly, a safe water draining treatment with good efficiency can be conducted relative to radioactive iodine-containing liquid wastes at a reduced cost. (T.M.)

  4. Stakeholders involvement in the decommissioning processes in Italy

    International Nuclear Information System (INIS)

    Dionisi, Mario

    2006-01-01

    The aim of this paper is to present the situation about stakeholders involvement in Italy in the framework of the decommissioning process of the Italian nuclear installations, and in particular the specific experience of the Italian Regulatory Body APAT. Specific aspects and APAT initiatives for building confidence of stakeholders in the process of the release of solid material from the regulatory control are presented. Content: Decommissioning activities in Italy, Decommissioning licensing procedures (Site and material release, APAT - ARPA Partnership approach in the clearance process)

  5. Improved mechanical properties of retorted carrots by ultrasonic pre-treatments.

    Science.gov (United States)

    Day, Li; Xu, Mi; Øiseth, Sofia K; Mawson, Raymond

    2012-05-01

    The use of ultrasound pre-processing treatment, compared to blanching, to enhance mechanical properties of non-starchy cell wall materials was investigated using carrot as an example. The mechanical properties of carrot tissues were measured by compression and tensile testing after the pre-processing treatment prior to and after retorting. Carrot samples ultrasound treated for 10 min at 60 °C provided a higher mechanical strength (P<0.05) to the cell wall structure than blanching for the same time period. With the addition of 0.5% CaCl(2) in the pre-treatment solution, both blanching and ultrasound treatment showed synergistic effect on enhancing the mechanical properties of retorted carrot pieces. At a relatively short treatment time (10 min at 60 °C) with the use of 0.5% CaCl(2), ultrasound treatment achieved similar enhancement to the mechanical strength of retorted carrots to blanching for a much longer time period (i.e. 40 min). The mechanism involved appears to be related to the stress responses present in all living plant matter. However, there is a need to clarify the relative importance of the potential stress mechanisms in order to get a better understanding of the processing conditions likely to be most effective. The amount of ultrasound treatment required is likely to involve low treatment intensities and there are indications from the structural characterisation and mechanical property analyses that the plant cell wall tissues were more elastic than that accomplished using low temperature long time blanching. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

  6. Solar assisted alkali pretreatment of garden biomass: Effects on lignocellulose degradation, enzymatic hydrolysis, crystallinity and ultra-structural changes in lignocellulose

    International Nuclear Information System (INIS)

    Gabhane, Jagdish; William, S.P.M. Prince; Vaidya, Atul N.; Das, Sera; Wate, Satish R.

    2015-01-01

    Highlights: • SAAP is an efficient and economic means of pretreatment. • SAAP was found to be efficient in lignin and hemicellulose removal. • SAAP enhanced the enzymatic hydrolysis. • FTIR, XRD and SEM provided vivid understanding about the mode of action of SAAP. • Mass balance closer of 98% for pretreated GB confirmed the reliability of SAAP. - Abstract: A comprehensive study was carried out to assess the effectiveness of solar assisted alkali pretreatment (SAAP) on garden biomass (GB). The pretreatment efficiency was assessed based on lignocellulose degradation, conversion of cellulose into reducing sugars, changes in the ultra-structure and functional groups of lignocellulose and impact on the crystallinity of cellulose, etc. SAAP was found to be efficient for the removal of lignin and hemicellulose that facilitated enzymatic hydrolysis of cellulose. FTIR and XRD studies provided details on the effectiveness of SAAP on lignocellulosic moiety and crystallinity of cellulose. Scanning electron microscopic analysis showed ultra-structural disturbances in the microfibrils of GB as a result of pretreatment. The mass balance closer of 97.87% after pretreatment confirmed the reliability of SAAP pretreatment. Based on the results, it is concluded that SAAP is not only an efficient means of pretreatment but also economical as it involved no energy expenditure for heat generation during pretreatment

  7. Reducing biomass recalcitrance via mild sodium carbonate pretreatment.

    Science.gov (United States)

    Mirmohamadsadeghi, Safoora; Chen, Zhu; Wan, Caixia

    2016-06-01

    This study examined the effects of mild sodium carbonate (Na2CO3) pretreatment on enzymatic hydrolysis of different feedstocks (i.e., corn stover, Miscanthus, and switchgrass). The results showed that sodium carbonate pretreatment markedly enhanced the sugar yields of the tested biomass feedstocks. The pretreated corn stover, Miscanthus, and switchgrass gave the glucose yields of 95.1%, 62.3%, and 81.3%, respectively, after enzymatic hydrolysis. The above glucose yields of pretreated feedstocks were 2-4 times that of untreated ones. The pretreatment also enhanced the xylose yields, 4 times for corn stover and 20 times for both Miscanthus and switchgrass. Sodium carbonate pretreatment removed 40-59% lignin from the tested feedstocks while preserving most of cellulose (sodium carbonate pretreatment was effective for reducing biomass recalcitrance and subsequently improving the digestibility of lignocellulosic biomass. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Study on the Mechanism of mTOR-Mediated Autophagy during Electroacupuncture Pretreatment against Cerebral Ischemic Injury

    Directory of Open Access Journals (Sweden)

    Zhou-Quan Wu

    2016-01-01

    Full Text Available This study is aimed at investigating the association between the electroacupuncture (EA pretreatment-induced protective effect against early cerebral ischemic injury and autophagy. EA pretreatment can protect cerebral ischemic and reperfusion injuries, but whether the attenuation of early cerebral ischemic injury by EA pretreatment was associated with autophagy is not yet clear. This study used the middle cerebral artery occlusion model to monitor the process of ischemic injury. For rats in the EA pretreatment group, EA pretreatment was conducted at Baihui acupoint before ischemia for 30 min for 5 consecutive days. The results suggested that EA pretreatment significantly increased the expression of autophagy in the cerebral cortical area on the ischemic side of rats. But the EA pretreatment-induced protective effects on the brain could be reversed by the specific inhibitor 3-methyladenine of autophagy. Additionally, the Pearson correlation analysis indicated that the impact of EA pretreatment on p-mTOR (2481 was negatively correlated with its impact on autophagy. In conclusion, the mechanism of EA pretreatment at Baihui acupoint against cerebral ischemic injury is mainly associated with the upregulation of autophagy expression, and its regulation of autophagy may depend on mTOR-mediated signaling pathways.

  9. Modeling of pretreatment and acidogenic fermentation of the organic fraction of municipal solid wastes

    Energy Technology Data Exchange (ETDEWEB)

    Beccari, M; Longo, G; Majone, M; Rolle, E; Scarinci, A [Rome ' ' La Sapienza' ' Univ. (Italy). Dept. of Chemistry

    1993-01-01

    The organic fraction of municipal solid waste represents a potential feedstock to be treated through biorefining. However, the process feasibility strongly depends on the effectiveness of a chemical pretreatment. Consequently, experimentation aimed at choosing the optimal type of reagent (alkali or acids) and optimal operating conditions was carried out. The best results were obtained using NaOH at room temperature. Solubilization data are in good agreement with a kinetics based on two competing reactions. Simulation of the overall process (pretreatment and acidogenic fermentation) taking place in two CFSTR reactors shows that an optimum ratio exists between the hydraulic residence times of the two stages of the process. (author)

  10. A Novel Approach To Mineral Carbonation: Enhancing Carbonation While Avoiding Mineral Pretreatment Process Cost

    Energy Technology Data Exchange (ETDEWEB)

    Michael J. McKelvy; Andrew V. G. Chizmeshya; Kyle Squires; Ray W. Carpenter; Hamdallah Bearat

    2006-06-21

    Known fossil fuel reserves, especially coal, can support global energy demands for centuries to come, if the environmental problems associated with CO{sub 2} emissions can be overcome. Unlike other CO{sub 2} sequestration candidate technologies that propose long-term storage, mineral sequestration provides permanent disposal by forming geologically stable mineral carbonates. Carbonation of the widely occurring mineral olivine (e.g., forsterite, Mg{sub 2}SiO{sub 4}) is a large-scale sequestration process candidate for regional implementation, which converts CO{sub 2} into the environmentally benign mineral magnesite (MgCO{sub 3}). The primary goal is cost-competitive process development. As the process is exothermic, it inherently offers low-cost potential. Enhancing carbonation reactivity is key to economic viability. Recent studies at the U.S. DOE Albany Research Center have established that aqueous-solution carbonation using supercritical CO{sub 2} is a promising process; even without olivine activation, 30-50% carbonation has been achieved in an hour. Mechanical activation (e.g., attrition) has accelerated the carbonation process to an industrial timescale (i.e., near completion in less than an hour), at reduced pressure and temperature. However, the activation cost is too high to be economical and lower cost pretreatment options are needed. Herein, we report our second year progress in exploring a novel approach that offers the potential to substantially enhance carbonation reactivity while bypassing pretreatment activation. As our second year progress is intimately related to our earlier work, the report is presented in that context to provide better overall understanding of the progress made. We have discovered that robust silica-rich passivating layers form on the olivine surface during carbonation. As carbonation proceeds, these passivating layers thicken, fracture and eventually exfoliate, exposing fresh olivine surfaces during rapidly

  11. Effect of Mucuna pruriens Seed Extract Pretreatment on the Responses of Spontaneously Beating Rat Atria and Aortic Ring to Naja sputatrix (Javan Spitting Cobra Venom

    Directory of Open Access Journals (Sweden)

    Shin Yee Fung

    2012-01-01

    Full Text Available Mucuna pruriens Linn. (velvet bean has been used by native Nigerians as a prophylactic for snakebite. Rats pretreated with M. pruriens seed extract (MPE have been shown to protect against the lethal and cardiovascular depressant effects of Naja sputatrix (Javan spitting cobra venoms, and the protective effect involved immunological neutralization of the venom toxins. To investigate further the mechanism of the protective effect of MPE pretreatment against cobra venom toxicity, the actions of Naja sputatrix venom on spontaneously beating rat atria and aortic rings isolated from both MPE pretreated and untreated rats were studied. Our results showed that the MPE pretreatment conferred protection against cobra venom-induced depression of atrial contractility and atrial rate in the isolated atrial preparations, but it had no effect on the venom-induced contractile response of aortic ring preparation. These observations suggested that the protective effect of MPE pretreatment against cobra venom toxicity involves a direct protective action of MPE on the heart function, in addition to the known immunological neutralization mechanism, and that the protective effect does not involve action on blood vessel contraction. The results also suggest that M. pruriens seed may contain novel cardioprotective agent with potential therapeutic value.

  12. The characteristic changes of betung bamboo (Dendrocalamus asper pretreated by fungal pretreatment

    Directory of Open Access Journals (Sweden)

    Widya Fatriasari

    2014-05-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 The fungal pretreatment effect on chemical structural and morphological changes of Betung Bamboo was evaluated based on its biomass components after being cultivated by white rot fungi, Trametes versicolor. Betung bamboo powder (15 g was exposed to liquid inoculum of white rot fungi and incubated at 270C for 15, 30 and 45 days. The treated samples were then characterized by FT-IR spectroscopy, X-Ray diffraction and SEM-EDS analyses. Cultivation for 30 days with 5 and 10% loadings retained greater selectivity compared to that of the other treatments. FTIR spectra demonstrated that the fungus affected the decreasing of functional group quantities without changing the functional groups. The decrease in intensity at wave number of 1246 cm-1 (guaiacyl of lignin was greater than that at wave number of 1328 cm-1 (deformation combination of syringyl and xylan after fungal treatment. X-ray analysis showed the pretreated samples had a higher crystallinity than the untreated ones which might be due to the cleavage of amorphous fractions of cellulose. The pretreated samples have more fragile than the untreated ones confirmed by SEM. Crystalline allomorph calculated by XRD analysis showed that fungus pretreatment for 30 days has transformed triclinic structure of cellulose to monoclinic structure.

  13. Effect of copper surface pre-treatment on the properties of CVD grown graphene

    Directory of Open Access Journals (Sweden)

    Min-Sik Kim

    2014-12-01

    Full Text Available Here, we report the synthesis of high quality monolayer graphene on the pre-treated copper (Cu foil by chemical vapor deposition method. The pre-treatment process, which consists of pre-annealing in a hydrogen ambient, followed by diluted nitric acid etching of Cu foil, helps in removing impurities. These impurities include native copper oxide and rolling lines that act as a nucleation center for multilayer graphene. Raman mapping of our graphene grown on pre-treated Cu foil primarily consisted of ∼98% a monolayer graphene with as compared to 75 % for the graphene grown on untreated Cu foil. A high hydrogen flow rate during the pre-annealing process resulted in an increased I2D/IG ratio of graphene up to 3.55. Uniform monolayer graphene was obtained with a I2D/IG ratio and sheet resistance varying from 1.84 – 3.39 and 1110 – 1290 Ω/□, respectively.

  14. 44 CFR 5.8 - Records involved in litigation or other judicial process.

    Science.gov (United States)

    2010-10-01

    ... litigation or other judicial process. 5.8 Section 5.8 Emergency Management and Assistance FEDERAL EMERGENCY... Provisions § 5.8 Records involved in litigation or other judicial process. Where there is reason to believe that any records requested may be involved in litigation or other judicial process in which the United...

  15. Ethanol production from bamboo using mild alkaline pre-extraction followed by alkaline hydrogen peroxide pretreatment.

    Science.gov (United States)

    Yuan, Zhaoyang; Wen, Yangbing; Kapu, Nuwan Sella

    2018-01-01

    A sequential two-stage pretreatment process comprising alkaline pre-extraction and alkaline hydrogen peroxide pretreatment (AHP) was investigated to convert bamboo carbohydrates into bioethanol. The results showed that mild alkaline pre-extraction using 8% (w/w) sodium hydroxide (NaOH) at 100°C for 180min followed by AHP pretreatment with 4% (w/w) hydrogen peroxide (H 2 O 2 ) was sufficient to generate a substrate that could be efficiently digested with low enzyme loadings. Moreover, alkali pre-extraction enabled the use of lower H 2 O 2 charges in AHP treatment. Two-stage pretreatment followed by enzymatic hydrolysis with only 9FPU/g cellulose led to the recovery of 87% of the original sugars in the raw feedstock. The use of the pentose-hexose fermenting Saccharomyces cerevisiae SR8u strain enabled the utilization of 95.7% sugars in the hydrolysate to reach 4.6%w/v ethanol titer. The overall process also enabled the recovery of 62.9% lignin and 93.8% silica at high levels of purity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Potential of Black Liquor of Potassium Hydroxide to Pretreat Corn Stover for Biomethane Production

    Directory of Open Access Journals (Sweden)

    Muhammad Abdul Hanan Siddhu

    2016-04-01

    Full Text Available Reducing the pretreatment cost of lignocellulosic biomass by utilizing alkali to alter its recalcitrant nature is an effective method for biofuel production. In this experiment, 1.5% KOH solution and its black liquor (spent liquor of KOH (BL were applied to pretreat corn stover (CS at a temperature of 20 °C to enhance the digestibility for anaerobic digestion (AD. Results showed no significant difference in weighted average methane content on the basis of experimental methane and biogas yields between BL-treated and original KOH-treated CS after AD. The BL process significantly increased the overall methane yield by 52.4% compared with untreated CS (135.2 mL/gVS, whereas no significant difference between the overall methane yields of 1.5% KOH-treated and BL-treated CS was observed. In addition, the BL process significantly saved water and KOH consumption, by 56.2% and 57.4%, respectively, compared with the 1.5% KOH pretreatment. Overall methane production was well explained by the modified Gompertz model. The physiochemical changes to CS after BL pretreatment were confirmed by SEM, FTIR, and XRD analyses. Our findings collectively suggest that recycling and reuse of KOH black liquor might be an efficient method for lignocellulosic biomass treatment and have the capability to reduce input costs in future AD processes.

  17. Chitosan pretreatment for cotton dyeing with black tea

    Science.gov (United States)

    Campos, J.; Díaz-García, P.; Montava, I.; Bonet-Aracil, M.; Bou-Belda, E.

    2017-10-01

    Chitosan is used in a wide range of applications due to its intrinsic properties. Chitosan is a biopolymer obtained from chitin and among their most important aspects highlights its bonding with cotton and its antibacterial properties. In this study two different molecular weight chitosan are used in the dyeing process of cotton with black tea to evaluate its influence. In order to evaluate the effect of the pretreatment with chitosan, DSC and reflection spectrophotometer analysis are performed. The curing temperature is evaluated by the DSC analysis of cotton fabric treated with 15 g/L of chitosan, whilst the enhancement of the dyeing is evaluated by the colorimetric coordinates and the K/S value obtained spectrophotometrically. This study shows the extent of improvement of the pretreatment with chitosan in dyeing with natural products as black tea.

  18. Pretreatment of Hanford purex plant first-cycle waste

    International Nuclear Information System (INIS)

    Gibson, M.W.; Gerboth, D.M.; Peters, B.B.

    1987-01-01

    A process has been developed to pretreat neutralized, first-cycle high-level waste from the fuels reprocessing facility (PUREX Plant) at the Hanford Site. The process separates solids from the supernate liquid, which contains soluble salts. The solids, including most of the fission products and transuranic elements, may then be vitrified for disposal, while the low-level supernate stream may be processed into a less expensive grout waste form. The process also includes ion exchange treatment of the separated supernate stream to remove radiocesium. A flow sheet based on these operations was completed to support a planned demonstration of the process in the Hanford site B Plant canyon facility

  19. Enzymatic hydrolysis of pretreated soybean straw

    International Nuclear Information System (INIS)

    Xu Zhong; Wang Qunhui; Jiang Zhaohua; Yang Xuexin; Ji Yongzhen

    2007-01-01

    In order to produce lactic acid, from agricultural residues such as soybean straw, which is a raw material for biodegradable plastic production, it is necessary to decompose the soybean straw into soluble sugars. Enzymatic hydrolysis is one of the methods in common use, while pretreatment is the effective way to increase the hydrolysis rate. The optimal conditions of pretreatment using ammonia and enzymatic hydrolysis of soybean straw were determined. Compared with the untreated straw, cellulose in straw pretreated by ammonia liquor (10%) soaking for 24 h at room temperature increased 70.27%, whereas hemicellulose and lignin in pretreated straw decreased to 41.45% and 30.16%, respectively. The results of infrared spectra (IR), scanning electron microscope (SEM) and X-ray diffraction (XRD) analysis also showed that the structure and the surface of the straw were changed through pretreatment that is in favor of the following enzymatic hydrolysis. maximum enzymatic hydrolysis rate of 51.22% was achieved at a substrate concentration of 5% (w/v) at 50 deg. C and pH 4.8 using cellulase (50 fpu/g of substrate) for 36 h

  20. HANFORD MEDIUM & LOW CURIE WASTE PRETREATMENT PROJECT PHASE 1 LAB REPORT

    Energy Technology Data Exchange (ETDEWEB)

    HAMILTON, D.W.

    2006-01-30

    A fractional crystallization (FC) process is being developed to supplement tank waste pretreatment capabilities provided by the Waste Treatment and Immobilization Plant (WTP). FC can process many tank wastes, separating wastes into a low-activity fraction (LAW) and high-activity fraction (HLW). The low-activity fraction can be immobilized in a glass waste form by processing in the bulk vitrification (BV) system.

  1. 40 CFR 403.6 - National pretreatment standards: Categorical standards.

    Science.gov (United States)

    2010-07-01

    ... falls within that particular subcategory. If an existing Industrial User adds or changes a process or... best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GENERAL PRE-TREAT-MENT REGULATIONS FOR EXIST-ING AND NEW...

  2. Surface pretreatments for medical application of adhesion

    Directory of Open Access Journals (Sweden)

    Weber Michael

    2003-09-01

    Full Text Available Abstract Medical implants and prostheses (artificial hips, tendono- and ligament plasties usually are multi-component systems that may be machined from one of three material classes: metals, plastics and ceramics. Typically, the body-sided bonding element is bone. The purpose of this contribution is to describe developments carried out to optimize the techniques , connecting prosthesis to bone, to be joined by an adhesive bone cement at their interface. Although bonding of organic polymers to inorganic or organic surfaces and to bone has a long history, there remains a serious obstacle in realizing long-term high-bonding strengths in the in vivo body environment of ever present high humidity. Therefore, different pretreatments, individually adapted to the actual combination of materials, are needed to assure long term adhesive strength and stability against hydrolysis. This pretreatment for metal alloys may be silica layering; for PE-plastics, a specific plasma activation; and for bone, amphiphilic layering systems such that the hydrophilic properties of bone become better adapted to the hydrophobic properties of the bone cement. Amphiphilic layering systems are related to those developed in dentistry for dentine bonding. Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body. The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m. This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body.

  3. The Interaction between Personality, Social Network Position and Involvement in Innovation Process

    NARCIS (Netherlands)

    E. Dolgova (Evgenia); W. van Olffen (Woody); F.A.J. van den Bosch (Frans); H.W. Volberda (Henk)

    2010-01-01

    textabstractAbstract This dissertation proposal investigates how personality and individuals’ social network position affect individuals’ involvement into the innovation process. It posits that people would feel inclined to become involved into the different phases of the innovation process

  4. Electrolytic pretreatment of urine

    Science.gov (United States)

    1977-01-01

    Electrolysis has been under evaluation for several years as a process to pretreat urine for ultimate recovery of potable water in manned spacecraft applications. The conclusions that were drawn from this investigation are the following: (1) A platinum alloy containing 10 percent rhodium has been shown to be an effective, corrosion-resistant anode material for the electrolytic pretreatment of urine. Black platinum has been found to be suitable as a cathode material. (2) The mechanism of the reactions occurring during the electrolysis of urine is two-stage: (a) a total Kjeldahl nitrogen and total organic carbon (TOC) removal in the first stage is the result of electrochemical oxidation of urea to CO2, H2O, and ammonia followed by chloride interaction to produce N2 from ammonia, (b) after the urea has been essentially removed and the chloride ions have no more ammonia to interact with, the chloride ions start to oxidize to higher valence states, thus producing perchlorates. (3) Formation of perchlorates can be suppressed by high/low current operation, elevated temperature, and pH adjustment. (4) UV-radiation showed promise in assisting electrolytic TOC removal in beaker tests, but was not substantiated in limited single cell testing. This may have been due to non-optimum configurations of the single cell test rig and the light source.

  5. Substrate-Specific Development of Thermophilic Bacterial Consortia by Using Chemically Pretreated Switchgrass.

    Science.gov (United States)

    Eichorst, Stephanie A; Joshua, Chijioke; Sathitsuksanoh, Noppadon; Singh, Seema; Simmons, Blake A; Singer, Steven W

    2014-12-01

    Microbial communities that deconstruct plant biomass have broad relevance in biofuel production and global carbon cycling. Biomass pretreatments reduce plant biomass recalcitrance for increased efficiency of enzymatic hydrolysis. We exploited these chemical pretreatments to study how thermophilic bacterial consortia adapt to deconstruct switchgrass (SG) biomass of various compositions. Microbial communities were adapted to untreated, ammonium fiber expansion (AFEX)-pretreated, and ionic-liquid (IL)-pretreated SG under aerobic, thermophilic conditions using green waste compost as the inoculum to study biomass deconstruction by microbial consortia. After microbial cultivation, gravimetric analysis of the residual biomass demonstrated that both AFEX and IL pretreatment enhanced the deconstruction of the SG biomass approximately 2-fold. Two-dimensional nuclear magnetic resonance (2D-NMR) experiments and acetyl bromide-reactive-lignin analysis indicated that polysaccharide hydrolysis was the dominant process occurring during microbial biomass deconstruction, and lignin remaining in the residual biomass was largely unmodified. Small-subunit (SSU) rRNA gene amplicon libraries revealed that although the dominant taxa across these chemical pretreatments were consistently represented by members of the Firmicutes, the Bacteroidetes, and Deinococcus-Thermus, the abundance of selected operational taxonomic units (OTUs) varied, suggesting adaptations to the different substrates. Combining the observations of differences in the community structure and the chemical and physical structure of the biomass, we hypothesize specific roles for individual community members in biomass deconstruction. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  6. Chemical Pretreatment Methods for the Production of Cellulosic Ethanol: Technologies and Innovations

    Directory of Open Access Journals (Sweden)

    Edem Cudjoe Bensah

    2013-01-01

    Full Text Available Pretreatment of lignocellulose has received considerable research globally due to its influence on the technical, economic and environmental sustainability of cellulosic ethanol production. Some of the most promising pretreatment methods require the application of chemicals such as acids, alkali, salts, oxidants, and solvents. Thus, advances in research have enabled the development and integration of chemical-based pretreatment into proprietary ethanol production technologies in several pilot and demonstration plants globally, with potential to scale-up to commercial levels. This paper reviews known and emerging chemical pretreatment methods, highlighting recent findings and process innovations developed to offset inherent challenges via a range of interventions, notably, the combination of chemical pretreatment with other methods to improve carbohydrate preservation, reduce formation of degradation products, achieve high sugar yields at mild reaction conditions, reduce solvent loads and enzyme dose, reduce waste generation, and improve recovery of biomass components in pure forms. The use of chemicals such as ionic liquids, NMMO, and sulphite are promising once challenges in solvent recovery are overcome. For developing countries, alkali-based methods are relatively easy to deploy in decentralized, low-tech systems owing to advantages such as the requirement of simple reactors and the ease of operation.

  7. APLIKASI THERMAL PRE-TREATMENT LIMBAH TANAMAN JAGUNG (Zea mays SEBAGAI CO·SUBSTRAT PADA PROSES ANAEROBIK DIGESTI UNTUK PRODUKSI BIOGAS

    Directory of Open Access Journals (Sweden)

    Darwin Darwin

    2016-04-01

    Full Text Available Thermal pre-treatment was given on corn stover in the purpose of breaking the lignin content; thus, it may help anaerobic microorganisms to convert polymer including cellulose and hemicelluloses into biogas. This study aimed to investigate the effects of thermal pre-treatment on corn stover in anaerobic digestion process related to the production of biogas as well as digestion process efficiency. This research was carried out by utilizing batch reactors where the temperature was maintained at mesophilic conditions above room temperature (33 ± 2 oC. Based on the result, it was known that thermal pre-treatment given on the corn stover may enhance anaerobic digestion process for biogas production at the first 10 days. This condition reduced the time of lag phase during anaerobic digestion. The biogas production of corn stover given thermal pre-treatment was slow at 26 days where their average total production were 12,412.5 mL,12,310 mL at 15 and 25 minutes thermal pre-treatment, respectively while biogas production of non pre-treated corn stover was 12,557 mL. The highest daily biogas production was accomplished by corn stover that was given thermal pre-treatment at 25 minutes (915 mL. Corn stover given with 15 minutes thermal pre-treatment also generated higher daily biogas production at day 9 (772.5 mL compared with corn stover that was not pre-treated (405 mL. This research also revealed that corn stover given thermal pre-treatment reached higher biogas yield compared with non pre-treated corn stover where their biogas yield were 670.39, 690.65 mL/g volatile solids added at 15 and 25 minutes thermal pre- treatment respectively, and 456.37 mL/g volatile solids added of non pre-treated corn stover. Keywords: Thermal pre-treatment, corn stover, anaerobic digestion, biogas   ABSTRAK Thermal pre-treatment diberikan pada limbah tanaman jagung dengan tujuan untuk memecahkan kandungan lignin yang terdapat pada limbah tanaman jagung sehingga memudahkan

  8. Processes involved in solving mathematical problems

    Science.gov (United States)

    Shahrill, Masitah; Putri, Ratu Ilma Indra; Zulkardi, Prahmana, Rully Charitas Indra

    2018-04-01

    This study examines one of the instructional practices features utilized within the Year 8 mathematics lessons in Brunei Darussalam. The codes from the TIMSS 1999 Video Study were applied and strictly followed, and from the 183 mathematics problems recorded, there were 95 problems with a solution presented during the public segments of the video-recorded lesson sequences of the four sampled teachers. The analyses involved firstly, identifying the processes related to mathematical problem statements, and secondly, examining the different processes used in solving the mathematical problems for each problem publicly completed during the lessons. The findings revealed that for three of the teachers, their problem statements coded as `using procedures' ranged from 64% to 83%, while the remaining teacher had 40% of his problem statements coded as `making connections.' The processes used when solving the problems were mainly `using procedures', and none of the problems were coded as `giving results only'. Furthermore, all four teachers made use of making the relevant connections in solving the problems given to their respective students.

  9. Startup pattern and performance enhancement of pilot-scale biofilm process for raw water pretreatment.

    Science.gov (United States)

    Yang, Guang-Feng; Feng, Li-Juan; Yang, Qi; Zhu, Liang; Xu, Jian; Xu, Xiang-Yang

    2014-11-01

    The quality of raw water is getting worse in developing countries because of the inadequate treatment of municipal sewage, industrial wastewater and agricultural runoff. Aiming at the biofilm enrichment and pollutant removal, two pilot-scale biofilm reactors were built with different biological carriers. Results showed that compared with the blank carrier, the biofilm was easily enriched on the biofilm precoated carrier and less nitrite accumulation occurred. The removal efficiencies of NH4(+)-N, DOC and UV254 increased under the aeration condition, and a optimum DO level for the adequate nitrification was 1.0-2.6mgL(-1) with the suitable temperature range of 21-22°C. Study on the trihalomethane prediction model indicated that the presentence of algae increased the risk of disinfection by-products production, which could be effectively controlled via manual algae removing and light shading. In this study, the performance of biofilm pretreatment process could be enhanced under the optimized condition of DO level and biofilm carrier. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Comparative study of sulfite pretreatments for robust enzymatic saccharification of corn cob residue

    Directory of Open Access Journals (Sweden)

    Bu Lingxi

    2012-12-01

    Full Text Available Abstract Background Corn cob residue (CCR is a kind of waste lignocellulosic material with enormous potential for bioethanol production. The moderated sulphite processes were used to enhance the hydrophily of the material by sulfonation and hydrolysis. The composition, FT-IR spectra, and conductometric titrations of the pretreated materials were measured to characterize variations of the CCR in different sulfite pretreated environments. And the objective of this study is to compare the saccharification rate and yield of the samples caused by these variations. Results It was found that the lignin in the CCR (43.2% had reduced to 37.8%, 38.0%, 35.9%, and 35.5% after the sulfite pretreatment in neutral, acidic, alkaline, and ethanol environments, respectively. The sulfite pretreatments enhanced the glucose yield of the CCR. Moreover, the ethanol sulfite sample had the highest glucose yield (81.2%, based on the cellulose in the treated sample among the saccharification samples, which was over 10% higher than that of the raw material (70.6%. More sulfonic groups and weak acid groups were produced during the sulfite pretreatments. Meanwhile, the ethanol sulfite treated sample had the highest sulfonic group (0.103 mmol/g and weak acid groups (1.85 mmol/g in all sulfite treated samples. In FT-IR spectra, the variation of bands at 1168 and 1190 cm-1 confirmed lignin sulfonation during sulfite pretreatment. The disappearance of the band at 1458 cm-1 implied the methoxyl on lignin had been removed during the sulfite pretreatments. Conclusions It can be concluded that the lignin in the CCR can be degraded and sulfonated during the sulfite pretreatments. The pretreatments improve the hydrophility of the samples because of the increase in sulfonic group and weak acid groups, which enhances the glucose yield of the material. The ethanol sulfite pretreatment is the best method for lignin removal and with the highest glucose yield.

  11. Metallothionein expression during liver regeneration after partial hepatectomy in cadmium-pretreated rats

    Energy Technology Data Exchange (ETDEWEB)

    Margeli, A.P. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece)); Theocharis, S.E. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece)); Yannacou, N.N. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece)); Spiliopoulou, C. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece)); Koutselinis, A. (Dept. of Forensic Medicine and Toxicology, School of Medicine, Univ. of Athens (Greece))

    1994-10-01

    Metallothionein is a low molecular mass protein inducible mainly by heavy metals, having high affinity for binding cadmium, zinc and copper. In the present study we investigated the expression of metallothionein in regenerating liver, at different time intervals, in cadmium pretreated partially hepatectomized rats. Liver metallothionein is highly expressed during regeneration induced by partial hepatectomy in rats, providing zinc within the rapidly growing tissue. Cadmium pretreatment caused inhibition of the first peak of liver regeneration, while metallothionein expression was markedly more prominent in the liver residues of cadmium-pretreated rats. These results demonstrate that although metallothionein able to bind temporarily metal ions as zinc and cadmium has been highly expressed, the liver regenerative process was inhibited possibly due to the effects of cadmium on other pivotal events necessary to the DNA replication. (orig.)

  12. The effect of wastewater pretreatment on nanofiltration membrane performance

    Directory of Open Access Journals (Sweden)

    Ali Hashlamon

    2017-03-01

    Full Text Available Membrane fouling is considered a serious obstacle for operation and cost efficiency in wastewater treatment using nanofiltration (NF. However, pretreatment is the most practical way to reduce this prior to NF. In this research, two types of wastewaters were pretreated with different methods prior to NF to examine the effect of pretreatment on membrane fouling in terms of turbidity, chemical oxygen demand (COD and permeate flux. Turbidity and COD were measured to assess solid foulants and organic species in the wastewater, respectively. The first sample was secondary treated sewage, which was pretreated using coagulation-flocculation-sedimentation (CFS only. Steady flux was increased from 24 L/m2h for wastewater without pretreatment to 32.1 L/m2h with pretreatment. COD was also eliminated after CFS/NF, and turbidity was reduced to 0.6 NTU. The second sample was diluted biodiesel wastewater, which was pretreated using a combination of powdered-activated carbon (PAC adsorption and CFS (PAC/CFS. Steady flux was increased from 22.3 L/m2h for wastewater without pretreatment to 28.7 L/m2h with pretreatment; biodiesel wastewater quality also improved. Turbidity was reduced from 12 to 0.6 NTU, and COD was reduced from 526 to 4 mg/L after NF with PAC/CFS pretreatment, while COD was reduced from 526 to 95 mg/L using NF without pretreatment.

  13. Ethanol Fermentation of Various Pretreated and Hydrolyzed Substrates at Low Initial pH

    Science.gov (United States)

    Kádár, Zsófia; Maltha, San Feng; Szengyel, Zsolt; Réczey, Kati; de Laat, Wim

    Lignocellulosic materials represent an abundant feedstock for bioethanol production. Because of their complex structure pretreatment is necessary to make it accessible for enzymatic attack. Steam pretreatment with or without acid catalysts seems to be one of the most promising techniques, which has already been applied for large variety of lignocellulosics in order to improve enzymatic digestibility. During this process a range of toxic compounds (lignin and sugar degradation products) are formed which inhibit ethanol fermentation. In this study, the toxicity of hemicellulose hydrolysates obtained in the steam pretreatment of spruce, willow, and corn stover were investigated in ethanol fermentation tests using a yeast strain, which has been previously reported to have a resistance to inhibitory compounds generated during steam pretreatment. To overcome bacterial contamination, fermentations were carried out at low initial pH. The fermentability of hemicellulose hydrolysates of pretreated lignocellulosic substrates at low pH gave promising results with the economically profitable final 5 vol% ethanol concentration corresponding to 85% of theoretical. Adaptation experiments have shown that inhibitor tolerance of yeast strain can be improved by subsequent transfer of the yeast to inhibitory medium.

  14. Pretreatment of Platinum/Tin Oxide-Catalyst

    Science.gov (United States)

    Hess, Robert V.; Paulin, Patricia A.; Miller, Irvin M.; Schryer, David R.; Sidney, Barry D.; Wood, George M.; Upchurch, Billy T.; Brown, Kenneth G.

    1987-01-01

    Addition of CO to He pretreatment doubles catalytic activity. In sealed, high-energy, pulsed CO2 laser, CO and O2 form as decomposition products of CO2 in laser discharge zone. Products must be recombined, because oxygen concentration of more than few tenths of percent causes rapid deterioration of power, ending in unstable operation. Promising low-temperature catalyst for combining CO and O2 is platinum on tin oxide. New development increases activity of catalyst so less needed for recombination process.

  15. 棉梭织物酶、碱氧短流程前处理工艺研究%Research on the short process pretreatment using enzyme and alkali oxygen for woven cotton fabrics

    Institute of Scientific and Technical Information of China (English)

    张伟超; 邢建伟; 徐成书

    2016-01-01

    采用酶冷堆退浆、煮漂一步法对棉梭织物进行短流程前处理,并对处理后的棉织物进行性能分析,得到最优工艺条件:酶冷堆置过程中退浆酶WT8404g/L、JFC 2g/L,一步法汽蒸过程中精练剂XQC 6g/L、硅酸钠6g/L、氢氧化钠5g/L、过氧化氢(100%)9g/L.在此工艺条件下前处理的效果与传统前处理工艺效果接近,退浆率可达到93%以上,白度为84,毛效达到11cm/30min,该工艺相比传统两步法前处理工艺可省去多道工序,具有碱用量少、节能节水等优点.%The cooled reactors enzyme desizing,scouring and bleaching of one step method for cotton woven fabrics was subj ected for short process of pretreatment,and the properties of the treated cotton fabric were tested,the optimum process conditions were obtained:desizing enzyme WT840 4g/L and JFC 2g/L in the process of cooled reactors enzyme,scouring agent XQC 6g/L,sodium silicate 6g/L, sodium hydroxide 5g/L,hydrogen peroxide(100%)9g/L in the process of one step steaming.Under the conditions of this process,the effects of the cotton fabric treated were close to those of the tradi-tional pretreatment with desizing rate more than 95%,the whiteness higher than 84 and capillary effect is 11cm/30min.The new pretreatment process has the advantages of short procedures,lower us-age of alkali,energy and water saving compared to traditional two step pretreatment process.

  16. Pretreatment of Eucalyptus in biphasic system for furfural production and accelerated enzymatic hydrolysis.

    Science.gov (United States)

    Zhang, Xiudong; Bai, Yuanyuan; Cao, Xuefei; Sun, Runcang

    2017-08-01

    Herein, an efficient biphasic pretreatment process was developed to improve the production of furfural (FF) and glucose from Eucalyptus. The influence of formic acid and NaCl on FF production from xylose in water and various biphasic systems was investigated. Results showed that the addition of formic acid and NaCl significantly promoted the FF yield, and the biphasic system of MIBK (methyl isobutyl ketone)/water exhibited the best performance for FF production. Then the Eucalyptus was pretreated in the MIBK/water system, and a maximum FF yield of 82.0% was achieved at 180°C for 60min. Surface of the pretreated Eucalyptus became relatively rough and loose, and its crystallinity index increased obviously due to the removal of hemicelluloses and lignin. The pretreated Eucalyptus samples showed much higher enzymatic hydrolysis rates (26.2-70.7%) than the raw Eucalyptus (14.5%). Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. 40 CFR 415.344 - Pretreatment standards for existing sources (PSES).

    Science.gov (United States)

    2010-07-01

    ... Pigments Production Subcategory § 415.344 Pretreatment standards for existing sources (PSES). (a) Existing... chrome pigments process wastewater into a publicly owned treatment works are subject only to the... standards for existing sources (PSES): Subpart AH—Chrome Pigments Pollutant or pollutant property PSES...

  18. 40 CFR 415.116 - Pretreatment standards for new sources (PSNS).

    Science.gov (United States)

    2010-07-01

    ...) EFFLUENT GUIDELINES AND STANDARDS INORGANIC CHEMICALS MANUFACTURING POINT SOURCE CATEGORY Potassium Metal Production Subcategory § 415.116 Pretreatment standards for new sources (PSNS). Except as provided in § 403.7... (PSNS): There shall be no discharge of process wastewater pollutants to navigable waters. ...

  19. 40 CFR 421.105 - Pretreatment standards for existing sources.

    Science.gov (United States)

    2010-07-01

    ... treatment works must comply with 40 CFR part 403 and achieve the following pretreatment standards for...) Subpart J—Acid Leach Wet Air Pollution Control. PSES Pollutant or pollutant property Maximum for any 1 day... (Commingled With Other Process or Nonprocess Waters). PSES Pollutant or pollutant property Maximum for any 1...

  20. Cellulose pretreatment with 1-n-butyl-3-methylimidazolium chloride for solid acid-catalyzed hydrolysis.

    Science.gov (United States)

    Kim, Soo-Jin; Dwiatmoko, Adid Adep; Choi, Jae Wook; Suh, Young-Woong; Suh, Dong Jin; Oh, Moonhyun

    2010-11-01

    This study has been focused on developing a cellulose pretreatment process using 1-n-butyl-3-methylimidazolium chloride ([bmim]Cl) for subsequent hydrolysis over Nafion(R) NR50. Thus, several pretreatment variables such as the pretreatment period and temperature, and the [bmim]Cl amount were varied. Additionally, the [bmim]Cl-treated cellulose samples were characterized by X-ray diffraction analysis, and their crystallinity index values including CI(XD), CI(XD-CI) and CI(XD-CII) were then calculated. When correlated with these values, the concentrations of total reducing sugars (TRS) obtained by the pretreatment of native cellulose (NC) and glucose produced by the hydrolysis reaction were found to show a distinct relationship with the [CI(NC)-CI(XD)] and CI(XD-CII) values, respectively. Consequently, the cellulose pretreatment step with [bmim]Cl is to loosen a crystalline cellulose through partial transformation of cellulose I to cellulose II and, furthermore, the TRS release, while the subsequent hydrolysis of [bmim]Cl-treated cellulose over Nafion(R) NR50 is effective to convert cellulose II to glucose. Copyright 2010 Elsevier Ltd. All rights reserved.

  1. Ethanol and biogas production after steam pretreatment of corn stover with or without the addition of sulphuric acid

    Directory of Open Access Journals (Sweden)

    Bondesson Pia-Maria

    2013-01-01

    Full Text Available Abstract Background Lignocellulosic biomass, such as corn stover, is a potential raw material for ethanol production. One step in the process of producing ethanol from lignocellulose is enzymatic hydrolysis, which produces fermentable sugars from carbohydrates present in the corn stover in the form of cellulose and hemicellulose. A pretreatment step is crucial to achieve efficient conversion of lignocellulosic biomass to soluble sugars, and later ethanol. This study has investigated steam pretreatment of corn stover, with and without sulphuric acid as catalyst, and examined the effect of residence time (5–10 min and temperature (190–210°C on glucose and xylose recovery. The pretreatment conditions with and without dilute acid that gave the highest glucose yield were then used in subsequent experiments. Materials pretreated at the optimal conditions were subjected to simultaneous saccharification and fermentation (SSF to produce ethanol, and remaining organic compounds were used to produce biogas by anaerobic digestion (AD. Results The highest glucose yield achieved was 86%, obtained after pretreatment at 210°C for 10 minutes in the absence of catalyst, followed by enzymatic hydrolysis. The highest yield using sulphuric acid, 78%, was achieved using pretreatment at 200°C for 10 minutes. These two pretreatment conditions were investigated using two different process configurations. The highest ethanol and methane yields were obtained from the material pretreated in the presence of sulphuric acid. The slurry in this case was split into a solid fraction and a liquid fraction, where the solid fraction was used to produce ethanol and the liquid fraction to produce biogas. The total energy recovery in this case was 86% of the enthalpy of combustion energy in corn stover. Conclusions The highest yield, comprising ethanol, methane and solids, was achieved using pretreatment in the presence of sulphuric acid followed by a process configuration in

  2. Hydrogen fermentation of food waste by alkali-shock pretreatment: microbial community analysis and limitation of continuous operation.

    Science.gov (United States)

    Jang, Sujin; Kim, Dong-Hoon; Yun, Yeo-Myeong; Lee, Mo-Kwon; Moon, Chungman; Kang, Won-Seok; Kwak, Seung-Shin; Kim, Mi-Sun

    2015-06-01

    In the study, at first, batch tests were performed to investigate the effect of alkali-shock on H2 production from food waste (FW). After alkali-pretreatment of FW at pH 9.0-13.0, the FW was cultivated under mesophilic condition at pH 6.0 for 30 h without external inoculum addition. The amount of H2 production from FW pretreated at pH 11.0 and 12.0 was higher than that achieved in other pretreatment pH. The main metabolite was butyrate, and Clostridium were dominant at pH 11.0 and 12.0. Meanwhile, lactate was the main metabolite with Enterococcus and Streptococcus being the dominant genus at other pretreatment pH. When the batch process was switched to a continuous mode, H2 production was significantly dropped due to the increased activity of H2-consumers. The reliability of alkali-pretreatment at pH 11.0 was proven by repeating the scale-up batch process, recording 1.57±0.11 mol H2/mol hexose(added) (17±2LH2/kg FW) and 4.39±0.32LH2/L/d. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Cellulose conversion of corn pericarp without pretreatment.

    Science.gov (United States)

    Kim, Daehwan; Orrego, David; Ximenes, Eduardo A; Ladisch, Michael R

    2017-12-01

    We report enzyme hydrolysis of cellulose in unpretreated pericarp at a cellulase loading of 0.25FPU/g pericarp solids using a phenol tolerant Aspergillus niger pectinase preparation. The overall protein added was 5mg/g and gave 98% cellulose conversion in 72h. However, for double the amount of enzyme from Trichoderma reesei, which is significantly less tolerant to phenols, conversion was only 16%. The key to achieving high conversion without pretreatment is combining phenol inhibition-resistant enzymes (such as from A. niger) with unground pericarp from which release of phenols is minimal. Size reduction of the pericarp, which is typically carried out in a corn-to-ethanol process, where corn is first ground to a fine powder, causes release of highly inhibitory phenols that interfere with cellulase enzyme activity. This work demonstrates hydrolysis without pretreatment of large particulate pericarp is a viable pathway for directly producing cellulose ethanol in corn ethanol plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Acrylamide generation in pre-treated potato chips

    DEFF Research Database (Denmark)

    Pedreschi, Franco; Kaack, Karl; Granby, Kit

    2008-01-01

    Acrylamide formation in potato slices fried at two different temperatures ( 170 and 190 degrees C) was investigated under different pre-processing conditions. Potato slices (Saturna variety, diameter: 37 mm, width: 2.2 mm) were either fried at 170 degrees C per 5 min or 190 degrees C per 3.5 min...... to reach a final moisture content of 1.8 g water/100g ( wet basis). Prior to frying, potato slices were treated in one of the following ways: (i) Raw slices without any pre-treatment were considered as the control; (ii) Blanching: which was accomplished in 2 temperature-time combinations: 60 degrees C....... Acrylamide content in potato chips was determined after frying at 170 or 190 degrees C. Frying at 190 degrees C increased by almost 130 percent the acrylamide content of all the pre-treated samples ( average value) fried at 170 degrees C. Soaking of blanched potato slices in the 3 g/100 g of NaCl solution...

  5. Classification of processes involved in sharing individual participant data from clinical trials.

    Science.gov (United States)

    Ohmann, Christian; Canham, Steve; Banzi, Rita; Kuchinke, Wolfgang; Battaglia, Serena

    2018-01-01

    Background: In recent years, a cultural change in the handling of data from research has resulted in the strong promotion of a culture of openness and increased sharing of data. In the area of clinical trials, sharing of individual participant data involves a complex set of processes and the interaction of many actors and actions. Individual services/tools to support data sharing are available, but what is missing is a detailed, structured and comprehensive list of processes/subprocesses involved and tools/services needed. Methods : Principles and recommendations from a published data sharing consensus document are analysed in detail by a small expert group. Processes/subprocesses involved in data sharing are identified and linked to actors and possible services/tools. Definitions are adapted from the business process model and notation (BPMN) and applied in the analysis. Results: A detailed and comprehensive list of individual processes/subprocesses involved in data sharing, structured according to 9 main processes, is provided. Possible tools/services to support these processes/subprocesses are identified and grouped according to major type of support. Conclusions: The list of individual processes/subprocesses and tools/services identified is a first step towards development of a generic framework or architecture for sharing of data from clinical trials. Such a framework is strongly needed to give an overview of how various actors, research processes and services could form an interoperable system for data sharing.

  6. TECHNICAL COMPARISON OF CANDIDATE ION EXCHANGE MEDIA FOR SMALL COLUMN ION EXCHANGE (SCIX) APPLICATIONS IN SUPPORT OF SUPPLEMENTAL LAW PRETREATMENT

    International Nuclear Information System (INIS)

    Ramsey, A.A.; Thorson, M.R.

    2010-01-01

    At-tank supplemental pretreatment including both filtration and small column ion exchange is currently under evaluation to facilitate salt waste retrieval and processing in the Hanford tank farms. Spherical resorcinol formaldehyde (sRF) resin is the baseline ion exchange resin for use in the Waste Treatment and Immobilization Plant (WTP). This document provides background and technical rationale to assist in determining whether spherical resorcinol formaldehyde (sRF) is also the appropriate ion exchange resin for supplemental LAW pretreatment processes and compares sRF with crystalline silicotitanate (CST) as potential supplemental pretreatment ion exchange media.

  7. Acid Pretreatment of Sago Wastewater for Biohydrogen Production

    Science.gov (United States)

    Illi Mohamad Puad, Noor; Rahim, Nurainin Farhan Abd; Suhaida Azmi, Azlin

    2018-03-01

    Biohydrogen has been recognized to be one of the future renewable energy sources and has the potential in solving the greenhouse effects. In this study, Enterobacter aerogenes (E. aerogenes) was used as the biohydrogen producer via dark fermentation process using sago wastewater as the substrate. However, pretreatment of sago wastewater is required since it consists of complex sugars that cannot be utilized directly by the bacteria. This study aimed to use acid pretreatment method to produce high amount of glucose from sago wastewater. Three different types of acid: sulfuric acid (H2SO4); hydrochloric acid (HCl) and nitric acid (HNO3) were screened for the best acid in producing a maximum amount of glucose. H2SO4 gave the highest amount of glucose which was 9.406 g/L. Design of experiment was done using Face-centred Central Composite Design (FCCCD) tool under Response Surface Methodology (RSM) in Design Expert 9 software. The maximum glucose (9.138 g/L) was recorded using 1 M H2SO4 at 100 °C for 60 min. A batch dark fermentation using E. aerogenes was carried out and it was found that pretreated sago wastewater gave a higher hydrogen concentration (1700 ppm) compared to the raw wastewater (410 ppm).

  8. Chemical pretreatment of lignocellulosic agroindustrial waste for methane production.

    Science.gov (United States)

    Pellera, Frantseska-Maria; Gidarakos, Evangelos

    2018-01-01

    This study investigates the effect of different chemical pretreatments on the solubilization and the degradability of different solid agroindustrial waste, namely winery waste, cotton gin waste, olive pomace and juice industry waste. Eight different reagents were investigated, i.e. sodium hydroxide (NaOH), sodium bicarbonate (NaHCO 3 ), sodium chloride (NaCl), citric acid (H 3 Cit), acetic acid (AcOH), hydrogen peroxide (H 2 O 2 ), acetone (Me 2 CO) and ethanol (EtOH), under three condition sets resulting in treatments of varying intensity, depending on process duration, reagent dosage and temperature. Results indicated that chemical pretreatment under more severe conditions is more effective on the solubilization of lignocellulosic substrates, such as those of the present study and among the investigated reagents, H 3 Cit, H 2 O 2 and EtOH appeared to be the most effective to this regard. At the same time, although chemical pretreatment in general did not improve the methane potential of the substrates, moderate to high severity conditions were found to generally be the most satisfactory in terms of methane production from pretreated materials. In fact, moderate severity treatments using EtOH for winery waste, H 3 Cit for olive pomace and H 2 O 2 for juice industry waste and a high severity treatment with EtOH for cotton gin waste, resulted in maximum specific methane yield values. Ultimately, the impact of pretreatment parameters on the different substrates seems to be dependent on their characteristics, in combination with the specific mode of action of each reagent. The overall energy balance of such a system could probably be improved by using lower operating powers and higher solid to liquid ratios. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Improved biohydrogen production and treatment of pulp and paper mill effluent through ultrasonication pretreatment of wastewater

    International Nuclear Information System (INIS)

    Hay, Jacqueline Xiao Wen; Wu, Ta Yeong; Juan, Joon Ching; Md Jahim, Jamaliah

    2015-01-01

    Highlights: • Ultrasonication facilitated the reuse of PPME in biohydrogen production. • Ultrasonication at an amplitude of 60% for 45 min produced the highest biohydrogen. • Ultrasonication increased the solubilization of PPME. • Higher net savings were obtained in pretreated PPME compared to raw PPME. - Abstract: Pulp and paper mill effluent (PPME), a rich cellulosic material, was found to have great potential for biohydrogen production through a photofermentation process. However, pretreatments were needed for degrading the complex structure of PPME before biohydrogen production. The aim of this study was to gain further insight into the effect of an ultrasonication process on PPME as a pretreatment method and on photofermentative biohydrogen production using Rhodobacter sphaeroides NCIMB. The ultrasonication amplitudes and times were varied between 30–90% and 15–60 min, respectively, and no dilution or nutrient supplementation was introduced during the biohydrogen production process. A higher biohydrogen yield, rate, light efficiency and COD removal efficiency were attained in conditions using ultrasonicated PPME. Among these different pretreatment conditions, PPME with ultrasonication pretreatment employing an amplitude of 60% and time of 45 min (A60:T45) gave the highest yield and rate of 5.77 mL H_2/mL medium and 0.077 mL H_2/mL h, respectively, while the raw PPME without ultrasonication showed a significantly lower yield and rate of 1.10 mL H_2/mL medium and 0.015 mL H_2/mL h, respectively. The results of this study demonstrated the potential of using ultrasonication as a pretreatment for PPME because the yield and rate of biohydrogen production were highly enhanced compared to the raw PPME. Economic analysis was also performed in this study, and in comparison with raw PPME, the highest net saving was $0.2132 for A60:T45.

  10. On energy consumption for size-reduction and yields from subsequent enzymatic saccharification of pretreated lodgepole pine

    Science.gov (United States)

    W. Zhu; Junyong Zhu; Roland Gleisner; X.J. Pan

    2010-01-01

    This study investigated the effects of chemical pretreatment and disk-milling conditions on energy consumption for size-reduction and the efficiency of enzymatic cellulose saccharification of a softwood. Lodgepole pine wood chips produced from thinnings of a 100-year-old unmanaged forest were pretreated by hot-water, dilute-acid, and two SPORL processes (Sulfite...

  11. Evaluation energy efficiency of bioconversion knot rejects to ethanol in comparison to other thermochemically pretreated biomass

    Science.gov (United States)

    Zhaojiang Wang; Menghua Qin; J.Y. Zhu; Guoyu Tian; Zongquan. Li

    2013-01-01

    Rejects from sulfite pulp mill that otherwise would be disposed of by incineration were converted to ethanol by a combined physical–biological process that was comprised of physical refining and simultaneous saccharification and fermentation (SSF). The energy efficiency was evaluated with comparison to thermochemically pretreated biomass, such as those pretreated by...

  12. Secretory processes involved in the formation of milk

    International Nuclear Information System (INIS)

    Knutsson, P.G.

    1976-01-01

    Current knowledge on milk formation is reviewed. Emphasis is given to sites of formation of protein, fat and lactose, and transfer of these compounds into the alveolar lumen. Further, the formation of the water phase of milk is thoroughly discussed, and evidence presented that milk formation includes both secretory and re-absorptive processes as well as diffusion. A short presentation of colostrum formation is included. Neither biochemical processes involved in synthesis of organic compounds nor mammary gland endocrinology are discussed. (author)

  13. Microbial Lipid Production from Enzymatic Hydrolysate of Pecan Nutshell Pretreated by Combined Pretreatment.

    Science.gov (United States)

    Qin, Lizhen; Qian, Hanyu; He, Yucai

    2017-12-01

    Biodiesel is a fuel composed of monoalkyl esters of long-chain fatty acids derived from renewable biomass sources. In this study, biomass waste pecan nutshell (PS) was attempted to be converted into microbial oil. For effective utilization of PS, sequential pretreatment with ethylene glycol-H 2 SO 4 -water (78:2:20, wt:wt:wt) at 130 °C for 30 min and aqueous ammonia (25 wt%) at 50 °C for 24 h was used to enhance its enzymatic saccharification. Significant linear correlation was obtained about delignification-saccharification (R 2  = 0.9507). SEM and FTIR results indicated that combination pretreatment could effectively remove lignin and xylan in PS for promoting its enzymatic saccharification. After 72 h, the reducing sugars from the hydrolysis of 50 g/L pretreated PS by combination pretreatment could be obtained at 73.6% yield. Using the recovered PS hydrolysates containing 20 g/L glucose as carbon source, microbial lipids produced from the PS hydrolysates by Rhodococcus opacus ACCC41043. Four fatty acids including palmitic acid (C16:0; 23.1%), palmitoleic acid (C16:1; 22.4%), stearic acid (C18:0; 15.3%), and oleic acid (C18:1; 23.9%) were distributed in total fatty acids. In conclusion, this strategy has potential application in the future.

  14. A new approach for bioethanol production from sugarcane bagasse using hydrodynamic cavitation assisted-pretreatment and column reactors.

    Science.gov (United States)

    Terán Hilares, Ruly; Kamoei, Douglas Viana; Ahmed, Muhammad Ajaz; da Silva, Silvio Silvério; Han, Jong-In; Santos, Júlio César Dos

    2018-05-01

    Hydrodynamic cavitation (HC) was adopted to assist alkaline-hydrogen peroxide pretreatment of sugarcane bagasse (SCB). In the following condition: 0.29 M of NaOH, 0.78% (v/v) of H 2 O 2 , 9.95 min of process time and 3 bar of inlet pressure, 95.4% of digestibility of cellulosic fraction was achieved. To take the best use of the pretreated biomass, the overall process was intensified by way of employing a packed bed flow-through column reactor and thus enabling to handle a high solid loading of 20%, thereby leading to cellulose and hemicellulose conversions to 74.7% and 75%, respectively. In the fermentation step, a bubble column reactor was introduced to maximize ethanol production from the pretreated SCB by Scheffersomyces stipitis NRRL-Y7124, resulting in 31.50 g/L of ethanol, 0.49 g/g of ethanol yield and 0.68 g/L.h of productivity. All this showed that our HC-assisted NaOH-H 2 O 2 pretreatment strategy along with the process intensification approach might offer an option for SCB-based biorefineries. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Ethanol production by Clostridium thermocellum grown on hydrothermally and organosolv-pretreated lignocellulosic materials

    Energy Technology Data Exchange (ETDEWEB)

    Hoermeyer, H F; Bonn, G; Bobleter, O; Tailliez, P; Millet, J; Girard, H; Aubert, J P

    1988-12-01

    Two strains of the thermophilic anaerobe Clostridium thermocellum, the wild type NCIB 10682 and its ethanol-hyperproductive mutant 647, were tested for their ability to grow on natural lignocellulosic materials (poplar wood, wheat straw) which had been pretreated by either hydrothermolysis or an organosolv process. For both materials and both strains, the dependencies of substrate accessibility on the pretreatment temperature were established in terms of cellulose hydrolysis and of product formation. In addition to the non-pH-controlled shake flask assays, in vitro experiments with cell-free culture supernatant and in vivo cellulolyses under pH regulation in a laboratory fermenter indicated that lignocellulosics pretreated at approx. 230/sup 0/C were degraded efficiently by the Clostridium strains investigated.

  16. Pretreatment of Hanford PUREX Plant first-cycle waste

    International Nuclear Information System (INIS)

    Gibson, M.W.; Gerboth, D.M.; Peters, B.B.

    1987-04-01

    A process has been developed to pretreat neutralized, first-cycle high-level waste from the fuels reprocessing facility at the Hanford Site. The process separates solids from the supernate liquid, which contains soluble salts. The solids, including most of the fission products and transuranic elements, may then be vitrified for disposal, while the low-level supernate stream may be processed into a less expensive grout waste form. The process also includes ion exchange treatment of the separated supernate stream to remove radiocesium. A flow sheet based on these operations was completed to support a planned demonstration of the process in the Hanford Site B Plant canyon facility. 5 refs., 2 figs., 5 tabs

  17. High Titer Ethanol and Lignosulfonate Production from SPORL Pretreated Poplar at Pilot Scale

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Haifeng [Key Laboratory of Low Carbon Energy and Chemical Engineering, Shandong University of Science and Technology, Qingdao (China); Forest Products Laboratory, USDA Forest Service, Madison, WI (United States); Zhu, J. Y., E-mail: jzhu@fs.fed.us; Gleisner, Roland [Forest Products Laboratory, USDA Forest Service, Madison, WI (United States); Qiu, Xueqing [School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou (China); Horn, Eric [BioPulping International, Inc., Madison, WI (United States)

    2015-04-27

    Poplar NE222 (Populus deltoides Bartr. ex Marsh × P. nigra L.) wood chips were pretreated in a 390 L pilot-scale rotating wood-pulping digester using a dilute sulfite solution of approximately pH 1.8 at 160°C for 40 min for bioconversion to ethanol and lignosulfonate (LS). An estimated combined hydrolysis factor (CHF) of 3.3 was used to scale the sulfite pretreatment temperature and time from laboratory bench scale experiments, which balanced sugar yield and inhibitor formation to facilitate high titer ethanol production through fermentation using S. cerevisiae YRH400 without detoxification. A terminal ethanol titer of 43.6 g L{sup -1} with a yield of 247 L tonne wood{sup -1} was achieved at total solids loading of 20%. The relatively low ethanol yield compared with yield from Sulfite pretreatment to overcome the recalcitrance of lignocelluloses (SPORL)-pretreated softwoods was due to inefficient utilization of xylose. The LS from SPORL has a substantially higher phenolic group (Ph-OH) content, though it was less sulfonated and had a lower molecular weight than a purified commercial softwood LS, and therefore has potential for certain commercial markets and future novel applications through further processing. The conversion efficiency achieved through process integration and simplification, demonstrated here, has significant importance to the entire supply chain of biofuel production from woody biomass.

  18. Functions and requirements for Project W-236B, Initial Pretreatment Module: Revision 1

    International Nuclear Information System (INIS)

    Swanson, L.M.

    1994-01-01

    Hanford Site tank waste supernatants will be pretreated to separate the low-level and high-level fractions. The low-level waste fraction, containing the bulk of the chemical constituents, must be processed into a vitrified waste product which will be disposed of onsite, in a safe, environmentally sound, and cost effective manner. The high-level waste fraction separated during supernatant pretreatment (primarily cesium) will be recombined with an additional high-level waste fraction generated from pretreatment of the tank waste sludges and solids. This combined high-level waste fraction will be immobilized as glass and disposed in a geological repository. The purpose of this document is to establish the functional requirements baseline for Project W-236B, Initial Pretreatment Module, by defining the level 5 and 6 functions and requirements for the project. A functional analysis approach has been used to break down the program functions and associated physical requirements that each function must meet. As the systems engineering process evolves, the design requirements document will replace this preliminary functions and requirements document. The design requirements document (DRD) will identify key decisions and associated uncertainties that impact the project. A revision of this document to a DRD is not expected to change the performance requirements or open issues. However, additional requirements and issues may be identified

  19. Response surface optimization of the thermal acid pretreatment of sugar beet pulp for bioethanol production using Trichoderma viride and Saccharomyces cerevisiae.

    Science.gov (United States)

    El-Gendy, Nour Sh; Madian, Hekmat R; Nassar, Hussein N; Amr, Salem S Abu

    2015-09-15

    Worldwide nowadays, relying on the second generation bioethanol from the lignocellulosic feedstock is a mandatory aim. However, one of the major drawbacks for high ethanol yield is the physical and chemical pretreatment of this kind of feedstock. As the pretreatment is a crucial process operation that modifies the lignocellulosic structure and enhances its accessibility for the high cost hydrolytic enzymes in an attempt to maximize the yield of the fermentable sugars. The objective of this work was to optimize and integrate a physicochemical pretreatment of one of the major agricultural wastes in Egypt; the sugar beet pulp (SBP) and the enzymatic saccharification of the pretreated SBP using a whole fungal cells with a separate bioethanol fermentation batch processes to maximize the bioethanol yield. The response surface methodology was employed in this study to statistically evaluate and optimize the conditions for a thermal acid pretreatment of SBP. The significance and the interaction effects of the concentrations of HCl and SBP and the reaction temperature and time were studied using a three-level central composite design of experiments. A quadratic model equation was obtained to maximize the production of the total reducing sugars. The validity of the predicted model was confirmed. The thermally acid pretreated SBP was further subjected to a solid state fermentation batch process using Trichoderma viride F94. The thermal acid pretreatment and fungal hydrolyzes were integrated with two parallel batch fermentation processes of the produced hydrolyzates using Saccharomyces cerevisiae Y39, that yielded a total of ≈ 48 g/L bioethanol, at a conversion rate of ≈ 0.32 g bioethanol/ g SBP. Applying the proposed integrated process, approximately 97.5 gallon of ethanol would be produced from a ton (dry weight) of SBP.

  20. Corrosion resistance of biomimetic calcium phosphate coatings on magnesium due to varying pretreatment time

    Energy Technology Data Exchange (ETDEWEB)

    Waterman, J., E-mail: jay.waterman@pg.canterbury.ac.nz [Department of Mechanical Engineering, University of Canterbury, Christchurch (New Zealand); Pietak, A. [Department of Anatomy and Structural Biology, University of Otago, Dunedin (New Zealand); Birbilis, N. [Department of Materials Engineering, Monash University (Australia); Woodfield, T. [Department of Mechanical Engineering, University of Canterbury, Christchurch (New Zealand); Department of Orthopaedic Surgery, University of Otago, Christchurch (New Zealand); Dias, G. [Department of Anatomy and Structural Biology, University of Otago, Dunedin (New Zealand); Staiger, M.P., E-mail: mark.staiger@canterbury.ac.nz [Department of Mechanical Engineering, University of Canterbury, Christchurch (New Zealand)

    2011-12-15

    Calcium phosphate coatings were prepared on magnesium substrates via a biomimetic coating process. The effects of a magnesium hydroxide pretreatment on the formation and the ultimate corrosion protection of the coatings were studied. The pretreatment layer was found to affect the amount of defects present in the coatings. Corrosion resistance of the coatings was studied in vitro using two simulated body fluids, 0.8% NaCl and Hanks solution. In NaCl, the resistance to corrosion of all samples decreases with time as corrosion proceeded through cracks and other defects in the coatings. Samples with no pretreatment displayed the highest corrosion resistance as these samples had the fewest defects in the coating. However, in Hanks solution, corrosion resistance increased with time due to additional nucleation of calcium phosphate from the fluid on to the substrate. In this solution, additional pretreatment time was beneficial to the overall corrosion resistance.

  1. Statistical process control applied to intensity modulated radiotherapy pretreatment controls with portal dosimetry;Maitrise statistique des processus appliquee aux controles avant traitement par dosimetrie portale en radiotherapie conformationnelle avec modulation d'intensite

    Energy Technology Data Exchange (ETDEWEB)

    Villani, N.; Noel, A. [Laboratoire de recherche en radiophysique, CRAN UMR 7039, Nancy universite-CNRS, 54 - Vandoeuvre-les-Nancy (France); Villani, N.; Gerard, K.; Marchesi, V.; Huger, S.; Noel, A. [Departement de radiophysique, centre Alexis-Vautrin, 54 - Vandoeuvre-les-Nancy (France); Francois, P. [Institut Curie, 75 - Paris (France)

    2010-06-15

    Purpose The first purpose of this study was to illustrate the contribution of statistical process control for a better security in intensity modulated radiotherapy (I.M.R.T.) treatments. This improvement is possible by controlling the dose delivery process, characterized by pretreatment quality control results. So, it is necessary to put under control portal dosimetry measurements (currently, the ionisation chamber measurements were already monitored by statistical process control thanks to statistical process control tools). The second objective was to state whether it is possible to substitute ionisation chamber with portal dosimetry in order to optimize time devoted to pretreatment quality control. Patients and methods At Alexis-Vautrin center, pretreatment quality controls in I.M.R.T. for prostate and head and neck treatments were performed for each beam of each patient. These controls were made with an ionisation chamber, which is the reference detector for the absolute dose measurement, and with portal dosimetry for the verification of dose distribution. Statistical process control is a statistical analysis method, coming from industry, used to control and improve the studied process quality. It uses graphic tools as control maps to follow-up process, warning the operator in case of failure, and quantitative tools to evaluate the process toward its ability to respect guidelines: this is the capability study. The study was performed on 450 head and neck beams and on 100 prostate beams. Results Control charts, showing drifts, both slow and weak, and also both strong and fast, of mean and standard deviation have been established and have shown special cause introduced (manual shift of the leaf gap of the multi-leaf collimator). Correlation between dose measured at one point, given with the E.P.I.D. and the ionisation chamber has been evaluated at more than 97% and disagreement cases between the two measurements were identified. Conclusion The study allowed to

  2. PRETREATING THORIUM FOR ELECTROPLATING

    Science.gov (United States)

    Beach, J.G.; Schaer, G.R.

    1959-07-28

    A method is presented for pretreating a thorium surface prior to electroplating the surface. The pretreatment steps of the invention comprise cleaning by vapor blasting the surface, anodically pickling in a 5 to 15% by volume aqueous hydrochloric acid bath with a current of 125 to 250 amp/sq ft for 3 to 5 min at room temperature, chemically pickling the surface in a 5 to 15% by volume of aqueous sulfuric acid for 3 to 5 min at room temperature, and rinsing the surface with water.

  3. Influence of ultrasound pretreatment on wood physiochemical structure.

    Science.gov (United States)

    He, Zhengbin; Wang, Zhenyu; Zhao, Zijian; Yi, Songlin; Mu, Jun; Wang, Xiaoxu

    2017-01-01

    As an initial step to increase the use of renewable biomass resources, this study was aimed at investigating the effects of ultrasound pretreatment on structural changes of wood. Samples were pretreated by ultrasound with the power of 300W and frequency of 28kHz in aqueous soda solution, aqueous acetic acid, or distilled water, then pretreated and control samples were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The results shown that ultrasound pretreatment is indeed effective in modifying the physiochemical structure of eucalyptus wood; the pretreatment decreased the quantity of alkali metals (e.g., potassium, calcium and magnesium) in the resulting material. Compared to the control group, the residual char content of samples pretreated in aqueous soda solution increased by 10.08%-20.12% and the reaction temperature decreased from 361°C to 341°C, however, in samples pretreated by ultrasound in acetic solution or distilled water, the residual char content decreased by 12.40%-21.45% and there were no significant differences in reactivity apart from a slightly higher maximum reaction rate. Ultrasound pretreatment increased the samples' crystallinity up to 35.5% and successfully removed cellulose, hemicellulose, and lignin from the samples; the pretreatment also increased the exposure of the sample to the treatment solutions, broke down sample pits, and generated collapses and microchannels on sample pits, and removed attachments in the samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Can washing-pretreatment eliminate the health risk of municipal solid waste incineration fly ash reuse?

    Science.gov (United States)

    Wang, Yao; Pan, Yun; Zhang, Lingen; Yue, Yang; Zhou, Jizhi; Xu, Yunfeng; Qian, Guangren

    2015-01-01

    Although the reuse of washing-pretreated MSWI fly ash bas been a hot topic, the associated risk is still an issue of great concern. The present study investigated the influence of washing-pretreatment on the total contents and bioaccessibility of heavy metals in MSWI fly ash. Furthermore, the study incorporated bioaccessibility adjustment into probabilistic risk assessment, to quantify the health risk from multi-pathway exposure to the concerned chemicals as a result of reusing washed MSWI fly ash. The results revealed that both water-washing and acid-washing process have resulted in the concentrated heavy metal content, and have reduced the bioaccessibility of heavy metals. Besides, the acid-washing process increased the cancer risk in most cases, while the effect of water-washing process was uncertain. However, both water-washing and acid-washing pretreatment could decrease the hazard index based on bioaccesilbility. Despite the uncertainties accompanying these procedures, the results indicated that, in this application scenario, only water-washing or acid-washing process cannot reduce the actual risk from all samples to acceptable level, especially for cancer risk. Copyright © 2014. Published by Elsevier Inc.

  5. Public involvement in decision making process in nuclear field

    International Nuclear Information System (INIS)

    Constantin, M.; Diaconu, D.

    2009-01-01

    Decision Making Process (DMP) in nuclear field is influenced by multiple factors such as: complex technical aspects, diversity of stakeholders, long term risks, psychological stresses, societal attitudes, etc. General public is sometimes considered as the only one of stakeholders, the involvement of the public being seen as a factor to obtain the acceptance in the late phase of DMP. Generally it is assessed by public consultation on the environment impact studies and by approval of the sitting through the local authorities decision. Modern society uses methods to involve public from the beginning of DMP. The paper shows a general view of the methods and tools used in Europe for public involvement in DMP. The process of construction of a continuous democratic dialog inside of Romanian Stakeholder Group (RSG) in the frame of the FP6-COWAM2 and CIP projects is presented with a focusing of the barriers and factors of disturbing the trust and collaboration between stakeholders. The influence on the public acceptance is also discussed. (authors)

  6. [Advances in research on mechanisms of seed pre-treatments.

    Science.gov (United States)

    Liu, Xu; Liu, Juan; Liu, Qian; Gao, Ya Ni; Wang, Quan Zhen

    2016-11-18

    Seeds play a vital role in nature and agro-ecosystems. The success of seed germination and the establishment of a normal seedling determine the propagation and survival of a plant species, but seed vigor is often seriously damaged because of seed aging, dormancy and the deterioration of natural habitat. Thus, exploring methods for improving germination quality is of great significance to ecology and the economy. Based on the latest international reports, seed pre-treatments are the most practical and effective methods for improving plant performance, increasing yields and enhancing stress resistance. This review provided a summary of the current pre-sowing treatment technologies and the physiological and biochemical responses of plants to these methods by addressing gene expression, cytological effects, enzyme system activities, material and energy metabolism, antioxidation mechanisms and signal transduction pathways. We also interpreted the mechanisms of the seed pre-treatment methods from aspects of seed germination acceleration and stress resistance enhancement. The bottleneck in seed pre-treatments at the cytological and molecular levels and the problems involved in their application were also discussed. Thus far, most studies had largely focused on the partial reaction alterations of plant biochemistry and enzyme activities, and they had generally been characterized by a lack of systematic and holistic study for applications to crop production. Finally, we proposed an outlook for further study in an attempt to provide a prospective and scientific reference for plant germplasm conservation, high-efficiency organic agriculture development and ecological environment re-construction.

  7. Charge exchange processes involving iron ions

    International Nuclear Information System (INIS)

    Phaneuf, R.A.

    1985-01-01

    A review and evaluation is given of the experimental data which are available for charge exchange processes involving iron ions and neutral H, H 2 and He. Appropriate scaling laws are presented, and their accuracy estimated for these systems. A bibliography is given of available data sources, as well as of useful data compilations and review articles. A procedure is recommended for providing single approximate formulae to the fusion community to describe total cross sections for electron capture by partially-stripped Fe/sup q+/ ions in collisions with H, H 2 and He, based on the scaling relationships suggested by Janev and Hvelplund

  8. High Titer and Yields Achieved with Novel, Low-Severity Pretreatment Strategy

    Energy Technology Data Exchange (ETDEWEB)

    2016-03-01

    NREL researchers obtained high concentration sugar syrups in enzymatic hydrolysis that are fermentable to ethanol and other advanced biofuels and intermediate products at high yields. The novel DMR process is simpler and bypasses all severe pretreatment methods, thus reducing the environmental impact. The results are unprecedented. Researchers achieved a high concentration of sugars (230g/L of monomeric sugar and 270 g/L total sugar) and this low toxicity, highly fermentable syrup yielded 86 g/L ethanol (> 90 percent conversion). In addition, the lignin streams from this process can readily be converted to jet or renewable diesel blendstocks through a hydrodeoxygenation step. The NREL-developed, low severity DMR process may potentially replace higher severity chemical pretreatments and associated expensive reactors constructed of exotic alloys with a simpler process, using commercial-scale equipment commonly associated with the pulp and paper industry, to produce high concentration, low toxicity sugar streams and highly reactive lignin streams from non-food renewable biomass for biological and catalytic upgrading to advanced biofuels and chemicals. The simpler DMR process with black liquor recycling could reduce environmental and life-cycle impacts, and repurpose shuttered pulp and paper mills to help revitalize rural economies.

  9. High-Yield Production of Levulinic Acid from Pretreated Cow Dung in Dilute Acid Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Jialei Su

    2017-02-01

    Full Text Available Agricultural waste cow dung was used as feedstock for the production of a high value–added chemical levulinic acid (LA in dilute acid aqueous solutions. A high LA yield of 338.9 g/kg was obtained from the pretreated cow dung, which was much higher than that obtained from the crude cow dung (135 g/kg, mainly attributed to the breakage of the lignin fraction in the lignocellulose structure of the cow dung by potassium hydroxide (KOH pretreatment, and thus enhanced the accessibility of cow dung to the acid sites in the catalytic reaction. Meanwhile, another value-added chemical formic acid could be obtained with a yield of ca. 160 g/kg in the process, implying a total production of ca. 500 g/kg yield for LA and formic acid from the pretreated cow dung with the proposed process. The developed process was shown to be tolerant to high initial substrate loading with a satisfied LA yield. This work provides a promising strategy for the value-increment utilization of liglocellulosic agricultural residues.

  10. Effect on Ca(OH)2 pretreatment to enhance biogas production of organic food waste

    Science.gov (United States)

    Junoh, H.; Yip, CH; Kumaran, P.

    2016-03-01

    This study investigated the effect of calcium hydroxide, Ca(OH)2 pretreatment in optimizing COD solubilisation and methane production through anaerobic digestion process. Two different parameters, chemical concentration (40-190 mEq/L) and pretreatment time (1-6 hours) were used to pretreat food waste. A central composite design and response surface methodology (RSM) was applied in obtaining the optimized condition for COD solubilisation. Result showed COD solubilisation was optimized at 166.98 mEq/L (equivalent to 6.1 g Ca(OH)2/L) for 1 hour. These conditions were applied through biomethane potential test with methane production of 864.19 mL/g VSdestructed and an increase of 20.0% as compared to untreated food waste.

  11. Environmental assessment of mild bisulfite pretreatment of forest residues into fermentable sugars for biofuel production.

    Science.gov (United States)

    Nwaneshiudu, Ikechukwu C; Ganguly, Indroneil; Pierobon, Francesca; Bowers, Tait; Eastin, Ivan

    2016-01-01

    Sugar production via pretreatment and enzymatic hydrolysis of cellulosic feedstock, in this case softwood harvest residues, is a critical step in the biochemical conversion pathway towards drop-in biofuels. Mild bisulfite (MBS) pretreatment is an emerging option for the breakdown and subsequent processing of biomass towards fermentable sugars. An environmental assessment of this process is critical to discern its future sustainability in the ever-changing biofuels landscape. The subsequent cradle-to-gate assessment of a proposed sugar production facility analyzes sugar made from woody biomass using MBS pretreatment across all seven impact categories (functional unit 1 kg dry mass sugar), with a specific focus on potential global warming and eutrophication impacts. The study found that the eutrophication impact (0.000201 kg N equivalent) is less than the impacts from conventional beet and cane sugars, while the global warming impact (0.353 kg CO2 equivalent) falls within the range of conventional processes. This work discusses some of the environmental impacts of designing and operating a sugar production facility that uses MBS as a method of treating cellulosic forest residuals. The impacts of each unit process in the proposed facility are highlighted. A comparison to other sugar-making process is detailed and will inform the growing biofuels literature.

  12. Monitoring of full-scale hydrodynamic cavitation pretreatment in agricultural biogas plant.

    Science.gov (United States)

    Garuti, Mirco; Langone, Michela; Fabbri, Claudio; Piccinini, Sergio

    2018-01-01

    The implementation of hydrodynamic cavitation (HC) pretreatment for enhancing the methane potential from agricultural biomasses was evaluated in a full scale agricultural biogas plant, with molasses and corn meal as a supplementary energy source. HC batch tests were run to investigate the influence on methane production, particle size and viscosity of specific energy input. 470kJ/kgTS was chosen for the full-scale implementation. Nearly 6-months of operational data showed that the HC pretreatment maximized the specific methane production of about 10%, allowing the biogas plant to get out of the fluctuating markets of supplementary energy sources and to reduce the methane emissions. HC influenced viscosity and particle size of digestate, contributing to reduce the energy demand for mixing, heating and pumping. In the light of the obtained results the HC process appears to be an attractive and energetically promising alternative to other pretreatments for the degradation of biomasses in biogas plant. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Effect of different pretreatments on dried chilli (Capsicum annum L.) quality

    Science.gov (United States)

    Anoraga, S. B.; Sabarisman, I.; Ainuri, M.

    2018-03-01

    Chilli (Capsicum annum L.) has significant price fluctuation. When the chilli price is declined, it causes food waste from unsold chilli. Therefore, drying chilli is a solution for this condition. Futhermore, it can be processed for various product like chilli powder, chilli sauce, etc. The aim of this study was to investigate the effect of different pretreatments on dried chilli quality. Chilli was blenched with hot water and steam before drying. The purpose of this pretreatments is to inactivate enzyme that prevents color and vitamin C losses. The quality parameters were moisture content, colour, vitamin C content, and capsaicin. Changes were observed by gravimetri method for moisture content, chromameter in L* a * b * colour model, and iodine titration for vitamin C. After drying for 20 hours at 60°C, chilli with steam blanching pretreatment dried rapidly than other samples. Unpretreated chilli had higher vitamin C content and better color than blanched chilli.

  14. Enzymatic pretreatment of wood chips for energy reductions in TMP production. A method for ranking of enzymes; Enzymatisk foerbehandling av flis foer energibesparing vid TMP tillverkning. Metod foer rankning av enzymer

    Energy Technology Data Exchange (ETDEWEB)

    Viforr, Silvia

    2010-11-15

    The production of thermomechanical pulp (TMP) demands high levels of energy. This, together with current expensive energy prices of nowadays results in significant costs, which is the reason why there is a demand for processes that require less energy. One way of reducing energy consumption in TMP refining could be to pretreat the wood chips with enzymes before the subsequent refining step. However, enzymes molecules are relatively large, which limits the impregnation process, and so the pores in the fibre walls are not large enough to fit the size of the enzymes. By mechanically pretreating wood chips in a screw feeder and press equipment, this opens the wood structure significantly which increases enzyme penetration. If enzymes are used for reducing energy consumption in TMP processes, it is necessary to optimise the enzymatic effect during the pretreatment of wood chips. It is very expensive to evaluate completely the effect of enzymes in large scale refining. Thus there is a need for other relevant methods for rapidly and effectively evaluating the energy saving effects when it comes to refining enzymatic pretreated wood chips. The aim of this project was to find a method for ranking of enzymes for pretreatment of chips for energy savings at TMP production. This method was to be independent of the type of enzyme used and of the type of pretreated wood chips involved. In order to asses the method for ranking enzymes being used in the pretreatment of chips to reduce energy input during refining, a comparison between the method and a mill trial was carried out in the mill trial. A known chemical pretreatment was used; here it was sulphonation of the wood chips before refining with low sulphite levels. Further, a laboratory wing refiner was used as an evaluation equipment. The trial started with the running conditions for a wing refiner that the best correspond with industrial refining. An evaluation was made on the effect of enzymatic pretreatment on energy

  15. Pretreatment of wheat straw for fermentation to methane

    International Nuclear Information System (INIS)

    Hashimoto, A.G.

    1986-01-01

    The effects of pretreating wheat straw with gamma-ray irradiation, ammonium hydroxide, and sodium hydroxide on methane yield, fermentation rate constant, and loss of feedstock constituents were evaluated using laboratory-scale batch fermentors. Results showed that methane yield increased as pretreatment alkali concentration increased, with the highest yield being 37% over untreated straw for the pretreatment consisting of sodium hydroxide dosage of 34 g OH - /kg volatile solids, at 90 0 C for 1 h. Gamma-ray irradiation had no significant effect on methane yield. Alkaline pretreatment temperatures above 100 0 C caused a decrease in methane yield. After more than 100 days of fermentation, all of the hemicellulose and more than 80% of the cellulose were degraded. The loss in cellulose and hemicellulose accounted for 100% of the volatile solids lost. No consistent effect of pretreatments on batch fermentation rates was noted. Semicontinuous fermentations of straw-manure mixtures confirmed the relative effectiveness of sodium- and ammonium-hydroxide pretreatments

  16. STAKEHOLDER INVOLVEMENT IN THE HEALTH TECHNOLOGY ASSESSMENT PROCESS IN LATIN AMERICA.

    Science.gov (United States)

    Pichon-Riviere, Andres; Soto, Natalie; Augustovski, Federico; Sampietro-Colom, Laura

    2018-06-11

    Latin American countries are taking important steps to expand and strengthen universal health coverage, and health technology assessment (HTA) has an increasingly prominent role in this process. Participation of all relevant stakeholders has become a priority in this effort. Key issues in this area were discussed during the 2017 Latin American Health Technology Assessment International (HTAi) Policy Forum. The Forum included forty-one participants from Latin American HTA agencies; public, social security, and private insurance sectors; and the pharmaceutical and medical device industry. A background paper and presentations by invited experts and Forum members supported discussions. This study presents a summary of these discussions. Stakeholder involvement in HTA remains inconsistently implemented in the region and few countries have established formal processes. Participants agreed that stakeholder involvement is key to improve the HTA process, but the form and timing of such improvements must be adapted to local contexts. The legitimization of both HTA and decision-making processes was identified as one of the main reasons to promote stakeholder involvement; but to be successful, the entire system of assessment and decision making must be properly staffed and organized, and certain basic conditions must be met, including transparency in the HTA process and a clear link between HTA and decision making. Participants suggested a need for establishing clear rules of participation in HTA that would protect HTA producers and decision makers from potentially distorting external influences. Such rules and mechanisms could help foster trust and credibility among stakeholders, supporting actual involvement in HTA processes.

  17. A STUDY OF BRACKISH WATER MEMBRANE WITH ULTRAFILTRATION PRETREATMENT IN INDONESIA´S COASTAL AREA

    Directory of Open Access Journals (Sweden)

    Elis Hastuti

    2012-01-01

    Full Text Available Water pollution and sea water intrusion to water sources in coastal areas result lack of provision safe drinking water by the drinking water regional company or coastal community. The existing water treatment plant that operated on brackish surface water or groundwater feed requires improving process. Membrane process could be a choice to treat the quality of brackish water to the level of potable water that designed to lower cost with high stabil flux and longer lifetime. This research focus on application of pilot plant of brackish water treatment using Ultrafiltration (UF membrane-air lift system as pretreatment of Reverse Osmosis (RO membrane-low pressure. Brackish water sources contain high colloidal and suspended solids that can cause fouling load of RO membranes and impair its performance. UF pretreatment operation tested by addition of compressed air into the feed (air lift system, resulted stable flux, reduces membrane fouling and low feed pressure. A flux of RO with UF pretreatment can produce drinking water of 30--61 L/m2·hour. It was observed, the good quality of RO permeate resulted by using a pretreatment of UF--PS (Polysulfone-UF with total dissolved solid rejection about 96--98% and color rejection about 99--100% at 5 or 8 bars of operation pressure. This paper concludes that performance of membrane technology with UF--air lift system pretreatment and RO membrane-low pressure could be accepted as condition of brackish water source in Indonesia coastal areas in producing drinking water.

  18. A study of brackish water membrane with ultrafiltration pretreatment in Indonesia’s coastal area

    Directory of Open Access Journals (Sweden)

    Elis Hastuti

    2012-06-01

    Full Text Available Water pollution and sea water intrusion to water sources in coastal areas result lack of provision safe drinking water by the drinking water regional company or coastal community. The existing water treatment plant that operated on brackish surface water or groundwater feed requires improving process. Membrane process could be a choice to treat the quality of brackish water to the level of potable water that designed to lower cost with high stabil flux and longer lifetime. This research focus on application of pilot plant of brackish water treatment using Ultrafiltration (UF membrane-air lift system as pretreatment of Reverse Osmosis (RO membrane-low pressure. Brackish water sources contain high colloidal and suspended solids that can cause fouling load of RO membranes and impair its performance. UF pretreatment operation tested by addition of compressed air into the feed (air lift system, resulted stable flux, reduces membrane fouling and low feed pressure. A flux of RO with UF pretreatment can produce drinking water of 30–61 L/m2∙hour. It was observed, the good quality of RO permeate resulted by using a pretreatment of UF–PS (Polysulfone-UF with total dissolved solid rejection about 96–98% and color rejection about 99–100% at 5 or 8 bars of operation pressure. This paper concludes that performance of membrane technology with UF–air lift system pretreatment and RO membrane-low pressure could be accepted as condition of brackish water source in Indonesia coastal areas in producing drinking water.

  19. Review: Waste-Pretreatment Technologies for Remediation of Legacy Defense Nuclear Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Wilmarth, William R.; Lumetta, Gregg J.; Johnson, Michael E.; Poirier, Micheal R.; Thompson, Major C.; Suggs, Patricia C.; Machara, N.

    2011-01-13

    The U.S. Department of Energy (DOE) is responsible for retrieving, immobilizing, and disposing of radioactive waste that has been generated during the production of nuclear weapons in the United States. The vast bulk of this waste material is stored in underground tanks at the Savannah River Site in South Carolina and the Hanford Site in Washington State. The general strategy for treating the radioactive tank waste consists of first separating the waste into high-level and low-activity fractions. This initial partitioning of the waste is referred to as pretreatment. Following pretreatment, the high-level fraction will be immobilized in a glass form suitable for disposal in a geologic repository. The low-activity waste will be immobilized in a waste form suitable for disposal at the respective site. This paper provides a review of recent developments in the application of pretreatment technologies to the processing of the Hanford and Savannah River radioactive tank wastes. Included in the review are discussions of 1) solid/liquid separations methods, 2) cesium separation technologies, and 3) other separations critical to the success of the DOE tank waste remediation effort. Also included is a brief discussion of the different requirements and circumstances at the two DOE sites that have in some cases led to different choices in pretreatment technologies.

  20. Subcritical Water-Carbon Dioxide Pretreatment of Oil Palm Mesocarp Fiber for Xylooligosaccharide and Glucose Production

    Directory of Open Access Journals (Sweden)

    Norlailiza Ahmad

    2018-05-01

    Full Text Available The present work aimed to investigate the pretreatment of oil palm mesocarp fiber (OPMF in subcritical H2O-CO2 at a temperature range from 150–200 °C and 20–180 min with CO2 pressure from 3–5 MPa. The pretreated solids and liquids from this process were separated by filtration and characterized. Xylooligosaccharides (XOs, sugar monomers, acids, furans and phenols in the pretreated liquids were analyzed by using HPLC. XOs with a degree of polymerization X2–X4 comprising xylobiose, xylotriose, xylotetraose were analyzed by using HPAEC-PAD. Enzymatic hydrolysis was performed on cellulose-rich pretreated solids to observe xylose and glucose production. An optimal condition for XOs production was achieved at 180 °C, 60 min, 3 MPa and the highest XOs obtained was 81.60 mg/g which corresponded to 36.59% of XOs yield from total xylan of OPMF. The highest xylose and glucose yields obtained from pretreated solids were 29.96% and 84.65%, respectively at cellulase loading of 10 FPU/g-substrate.

  1. The induction of menadione stress tolerance in the marine microalga, Dunaliella viridis, through cold pretreatment and modulation of the ascorbate and glutathione pools.

    Science.gov (United States)

    Madadkar Haghjou, Maryam; Colville, Louise; Smirnoff, Nicholas

    2014-11-01

    The effect of cold pretreatment on menadione tolerance was investigated in the cells of the marine microalga, Dunaliella viridis. In addition, the involvement of ascorbate and glutathione in the response to menadione stress was tested by treating cell suspensions with l-galactono-1,4-lactone, an ascorbate precursor, and buthionine sulfoximine, an inhibitor of glutathione synthesis. Menadione was highly toxic to non cold-pretreated cells, and caused a large decrease in cell number. Cold pretreatment alleviated menadione toxicity and cold pretreated cells accumulated lower levels of reactive oxygen species, and had enhanced antioxidant capacity due to increased levels of β-carotene, reduced ascorbate and total glutathione compared to non cold-pretreated cells. Cold pretreatment also altered the response to l-galactono-1,4-lactone and buthionine sulfoximine treatments. Combined l-galactono-1,4-lactone and menadione treatment was lethal in non-cold pretreated cells, but in cold-pretreated cells it had a positive effect on cell numbers compared to menadione alone. Overall, exposure of Dunaliella cells to cold stress enhanced tolerance to subsequent oxidative stress induced by menadione. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  2. Direct Succinic Acid Production from Minimally Pretreated Biomass Using Sequential Solid-State and Slurry Fermentation with Mixed Fungal Cultures

    Directory of Open Access Journals (Sweden)

    Jerico Alcantara

    2017-06-01

    Full Text Available Conventional bio-based succinic acid production involves anaerobic bacterial fermentation of pure sugars. This study explored a new route for directly producing succinic acid from minimally-pretreated lignocellulosic biomass via a consolidated bioprocessing technology employing a mixed lignocellulolytic and acidogenic fungal co-culture. The process involved a solid-state pre-fermentation stage followed by a two-phase slurry fermentation stage. During the solid-state pre-fermentation stage, Aspergillus niger and Trichoderma reesei were co-cultured in a nitrogen-rich substrate (e.g., soybean hull to induce cellulolytic enzyme activity. The ligninolytic fungus Phanerochaete chrysosporium was grown separately on carbon-rich birch wood chips to induce ligninolytic enzymes, rendering the biomass more susceptible to cellulase attack. The solid-state pre-cultures were then combined in a slurry fermentation culture to achieve simultaneous enzymatic cellulolysis and succinic acid production. This approach generated succinic acid at maximum titers of 32.43 g/L after 72 h of batch slurry fermentation (~10 g/L production, and 61.12 g/L after 36 h of addition of fresh birch wood chips at the onset of the slurry fermentation stage (~26 g/L production. Based on this result, this approach is a promising alternative to current bacterial succinic acid production due to its minimal substrate pretreatment requirements, which could reduce production costs.

  3. Pretreatment Engineering Platform (PEP) Integrated Test B Run Report--Caustic and Oxidative Leaching in UFP-VSL-T02A

    Energy Technology Data Exchange (ETDEWEB)

    Geeting, John GH; Bredt, Ofelia P.; Burns, Carolyn A.; Golovich, Elizabeth C.; Guzman-Leong, Consuelo E.; Josephson, Gary B.; Kurath, Dean E.; Sevigny, Gary J.; Aaberg, Rosanne L.

    2009-12-10

    Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed and operated as part of a plan to respond to issue M12, “Undemonstrated Leaching Processes” of the External Flowsheet Review Team (EFRT) issue response plan.( ) The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing.

  4. SBR treatment of olive mill wastewaters: dilution or pre-treatment?

    Science.gov (United States)

    Farabegoli, G; Chiavola, A; Rolle, E

    2012-01-01

    The olive-oil extraction industry is an economically important activity for many countries of the Mediterranean Sea area, with Spain, Greece and Italy being the major producers. This activity, however, may represent a serious environmental problem due to the discharge of highly polluted effluents, usually referred to as 'olive mill wastewaters' (OMWs). They are characterized by high values of chemical oxygen demand (COD) (80-300 g/L), lipids, total polyphenols (TPP), tannins and other substances difficult to degrade. An adequate treatment before discharging is therefore required to reduce the pollutant load. The aim of the present paper was to evaluate performances of a biological process in a sequencing batch reactor (SBR) fed with pre-treated OMWs. Pre-treatment consisted of a combined acid cracking (AC) and granular activated carbon (GAC) adsorption process. The efficiency of the system was compared with that of an identical SBR fed with the raw wastewater only diluted. Combined AC and GAC adsorption was chosen to be used prior to the following biological process due to its capability of providing high removal efficiencies of COD and TPP and also appreciable improvement of biodegradability. Comparing results obtained with different influents showed that best performances of the SBR were obtained by feeding it with raw diluted OMWs (dOMWs) and at the lowest dilution ratio (1:25): in this case, the removal efficiencies were 90 and 76%, as average, for COD and TPP, respectively. Feeding the SBR with either the pre-treated or the raw dOMWs at 1:50 gave very similar values of COD reduction (74%); however, an improvement of the TPP removal was observed in the former case.

  5. Pretreatment of Oil Palm Frond (OPF) with Ionic Liquid

    Science.gov (United States)

    Azmi, I. S.; Azizan, A.; Salleh, R. Mohd

    2018-05-01

    Pretreatment is the key to unlock the recalcitrance of lignocellulose for cellulosic biofuel production. Increasing attention has been drawn to ionic liquids (ILs) for pretreatment of lignocellulosic biomass because this approach was considered as a green engineering method over other conventional methods. In this work, Oil palm frond (OPF) was pretreated by using the ionic liquid 1-ethyl-3-methylimidazolium acetate [EMIM] Ac at the temperature of 99˚C for 3 hours. The characterization of the untreated and pretreated OPF was conducted by using different techniques which are Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The pretreatment of OPF with [EMIM] Ac was demonstrated to be effective evidenced by the significant reduction of Lateral Order Index (LOI) from FTIR, reduction of Crystallinity Index (CI) based on XRD and the significant morphology changes indicated by SEM. The CI value for the pretreated OPF decreased from 0.47 (untreated sample) to 0.28 while the LOI value decreased from 1.10 to 0.24 after pretreatment with [EMIM]Ac and the SEM morphology showed that the pretreated OPF becomes distorted and disordered.

  6. Has patients' involvement in the decision-making process changed over time?

    NARCIS (Netherlands)

    Brink-Muinen, A. van den; Dulmen, A.M. van; Haes, H.C.J.M. de; Visser, A.P.; Schellevis, F.G.; Bensing, J.M.

    2006-01-01

    Objective: To get insight into the changes over time of patients' involvement in the decision-making process, and into the factors contributing to patients' involvement and general practitioners' (GPs) communication related to the Medical Treatment Act (MTA) Issues: information about treatment,

  7. Has patients’ involvement in the decision-making process changed over time?

    NARCIS (Netherlands)

    Brink-Muinen, A. van den; Dulmen, S.M. van; Haes, H.C.J.M. de; Visser, A.P.; Schellevis, F.G.; Bensing, J.

    2006-01-01

    Objective To get insight into the changes over time of patients’ involvement in the decision-making process, and into the factors contributing to patients’ involvement and general practitioners’ (GPs) communication related to the Medical Treatment Act (MTA) issues: information about treatment,

  8. Effect of acid detergent fiber in hydrothermally pretreated sewage sludge on anaerobic digestion process

    Science.gov (United States)

    Takasaki, Rikiya; Yuan, Lee Chang; Kamahara, Hirotsugu; Atsuta, Youichi; Daimon, Hiroyuki

    2017-10-01

    Hydrothermal treatment is one of the pre-treatment method for anaerobic digestion. The application of hydrothermal treatment to sewage sludge of wastewater treatment plant has been succeeded to enhance the biogas production. The purpose of this study is to quantitatively clarify the effect of hydrothermal treatment on anaerobic digestion process focusing on acid detergent fiber (ADF) in sewage sludge, which is low biodegradability. The hydrothermal treatment experiment was carried out for 15 minutes between 160 °C and 200 °C respectively. The ADF content was decreased after hydrothermal treatment compared with untreated sludge. However, ADF content was increased when raising the treatment temperature from 160 °C to 200 °C. During batch anaerobic digestion experiment, untreated and treated sludge were examined for 10 days under 38 °C, and all samples were fed once based on volatile solids of samples. From batch anaerobic digestion experiment, as ADF content in sewage sludge increased, the total biogas production decreased. It was found that ADF content in sewage sludge influence on anaerobic digestion. Therefore, ADF could be one of the indicator to evaluate the effect of hydrothermal treatment to sewage sludge on anaerobic digestion.

  9. A Sequential Combination of Laccase Pretreatment and Enzymatic Hydrolysis for Glucose Production from Furfural Residues

    Directory of Open Access Journals (Sweden)

    Hailong Yu

    2014-06-01

    Full Text Available Furfural residues (FRs were pretreated with laccase or a laccase-mediator (1-hydroxybenzotriazole, HBT system to produce fermentable sugar for bioethanol production. Compared to laccase-only pretreatment, laccase-mediator pretreatment dissolved more lignin. Approximately 10.5% of the initially present lignin was removed when FRs were treated with a laccase loading of 100 U/g of dry substrate in 1% (w/w HBT at 48 °C for 24 h in an acetate buffer (pH 4.8. The enzymatic saccharification process was carried out by a combined laccase or laccase-mediator pretreatment without washing of the treated solids. The results showed that active laccase had a negative effect on the rate and yield of enzymatic hydrolysis. Laccase-oxidized HBT seriously reduced glucose yield. However, non-oxidized HBT increased glucose yield when laccase was deactivated at 121 °C for 20 min prior to enzymatic hydrolysis. The highest glucose yield, 80.9%, was obtained from the substrate pretreated with 100 U/g of dry substrate laccase and 1% (w/w HBT at 48 °C for 24 h in an acetate buffer (pH 4.8. Furthermore, the structures of FRs before and after laccase-mediator pretreatment were characterized by scanning electron microscopy (SEM and Fourier Transform Infrared spectroscopy (FT-IR.

  10. Microbial community structure in a thermophilic aerobic digester used as a sludge pretreatment process for the mesophilic anaerobic digestion and the enhancement of methane production.

    Science.gov (United States)

    Jang, Hyun Min; Park, Sang Kyu; Ha, Jeong Hyub; Park, Jong Moon

    2013-10-01

    An effective two-stage sewage sludge digestion process, consisting of thermophilic aerobic digestion (TAD) followed by mesophilic anaerobic digestion (MAD), was developed for efficient sludge reduction and methane production. Using TAD as a biological pretreatment, the total volatile suspended solid reduction (VSSR) and methane production rate (MPR) in the MAD reactor were significantly improved. According to denaturing gradient gel electrophoresis (DGGE) analysis, the results indicated that the dominant bacteria species such as Ureibacillus thermophiles and Bacterium thermus in TAD were major routes for enhancing soluble organic matter. TAD pretreatment using a relatively short SRT of 1 day showed highly increased soluble organic products and positively affected an increment of bacteria populations which performed interrelated microbial metabolisms with methanogenic species in the MAD; consequently, a quantitative real-time PCR indicated greatly increased Methanosarcinales (acetate-utilizing methanogens) in the MAD, resulting in enhanced methane production. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Hydrothermal pretreatment and enzymatic hydrolysis of mixed green and woody lignocellulosics from arid regions

    DEFF Research Database (Denmark)

    Ashraf, Muhammad Tahir; Thomsen, Mette Hedegaard; Schmidt, Jens Ejbye

    2017-01-01

    Utilization of multi-specie feedstocks is imperative for application of lignocellulosic biorefineries in arid regions. Different lignocellulosic residues vary in composition and anatomical features. Pretreatment and enzymatic hydrolysis are two processes at the front end of any lignocellulosics...... biorefinery applying biochemical pathway, and have to efficiently deal with the variance in the feedstock composition and properties. However, there is limited knowledge about effect of mixing different lignocellulosics on pretreatment and enzymatic hydrolysis yields. In this study effect of mixing...... on the yields from hydrothermal pretreatment and enzymatic hydrolysis was analyzed by mixing three different lignocellulosic residues — Bermuda grass, Jasmine hedges, and date palm fronds. Results showed that the individual and the mixed lignocellulosics gave same yields when treated under similar conditions...

  12. Comparison and Optimization of Saccharification Conditions of Alkaline Pre-Treated Triticale Straw for Acid and Enzymatic Hydrolysis Followed by Ethanol Fermentation

    Directory of Open Access Journals (Sweden)

    Rafał Łukajtis

    2018-03-01

    Full Text Available This paper concerns the comparison of the efficiency of two-stage hydrolysis processes, i.e., alkaline pre-treatment and acid hydrolysis, as well as alkaline pre-treatment followed by enzymatic hydrolysis, carried out in order to obtain reducing sugars from triticale straw. For each of the analyzed systems, the optimization of the processing conditions was carried out with respect to the glucose yield. For the alkaline pre-treatment, an optimal catalyst concentration was selected for constant values of temperature and pre-treatment time. For enzymatic hydrolysis, optimal process time and concentration of the enzyme preparation were determined. For the acidic hydrolysis, performed with 85% phosphoric acid, the optimum temperature and hydrolysis time were determined. In the hydrolysates obtained after the two-stage treatment, the concentration of reducing sugars was determined using HPLC. The obtained hydrolysates were subjected to ethanol fermentation. The concentrations of fermentation inhibitors are given and their effects on the alcoholic fermentation efficiency are discussed.

  13. Pretreatment and enzymatic hydrolysis of lignocellulosic biomass

    Science.gov (United States)

    Corredor, Deisy Y.

    The performance of soybean hulls and forage sorghum as feedstocks for ethanol production was studied. The main goal of this research was to increase fermentable sugars' yield through high-efficiency pretreatment technology. Soybean hulls are a potential feedstock for production of bio-ethanol due to their high carbohydrate content (≈50%) of nearly 37% cellulose. Soybean hulls could be the ideal feedstock for fuel ethanol production, because they are abundant and require no special harvesting and additional transportation costs as they are already in the plant. Dilute acid and modified steam-explosion were used as pretreatment technologies to increase fermentable sugars yields. Effects of reaction time, temperature, acid concentration and type of acid on hydrolysis of hemicellulose in soybean hulls and total sugar yields were studied. Optimum pretreatment parameters and enzymatic hydrolysis conditions for converting soybean hulls into fermentable sugars were identified. The combination of acid (H2SO4, 2% w/v) and steam (140°C, 30 min) efficiently solubilized the hemicellulose, giving a pentose yield of 96%. Sorghum is a tropical grass grown primarily in semiarid and dry parts of the world, especially in areas too dry for corn. The production of sorghum results in about 30 million tons of byproducts mainly composed of cellulose, hemicellulose, and lignin. Forage sorghum such as brown midrib (BMR) sorghum for ethanol production has generated much interest since this trait is characterized genetically by lower lignin concentrations in the plant compared with conventional types. Three varieties of forage sorghum and one variety of regular sorghum were characterized and evaluated as feedstock for fermentable sugar production. Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and X-Ray diffraction were used to determine changes in structure and chemical composition of forage sorghum before and after pretreatment and enzymatic hydrolysis

  14. Bioluminescence-Based Method for Measuring Assimilable Organic Carbon in Pretreatment Water for Reverse Osmosis Membrane Desalination ▿

    Science.gov (United States)

    Weinrich, Lauren A.; Schneider, Orren D.; LeChevallier, Mark W.

    2011-01-01

    A bioluminescence-based assimilable organic carbon (AOC) test was developed for determining the biological growth potential of seawater within the reverse osmosis desalination pretreatment process. The test uses Vibrio harveyi, a marine organism that exhibits constitutive luminescence and is nutritionally robust. AOC was measured in both a pilot plant and a full-scale desalination plant pretreatment. PMID:21148685

  15. Hydrothermal and alkaline hydrothermal pretreatments plus anaerobic digestion of sewage sludge for dewatering and biogas production: Bench-scale research and pilot-scale verification.

    Science.gov (United States)

    Li, Chunxing; Wang, Xingdong; Zhang, Guangyi; Yu, Guangwei; Lin, Jingjiang; Wang, Yin

    2017-06-15

    To test the feasibility and practicability of the process combing hydrothermal pretreatment for dewatering with biogas production for full utilization of sewage sludge, hydrothermal/alkaline hydrothermal pretreatments and in turn anaerobic digestion of the filtrates obtained after dewatering the pretreated sludge were performed at bench- and pilot-scales. The hydrothermal temperature fell within the range of 140 °C-220 °C and the pretreatment time varied from 30 min to 120 min. For the alkaline hydrothermal pretreatment the pH value of the sludge was adjusted to 9.0-11.0 by adding Ca(OH) 2 . The results showed that the dewaterability of the sewage sludge was improved with increasing pretreatment temperature but the impact of the pretreatment time was not significant. The addition of Ca(OH) 2 gave better performance on the subsequent mechanical dewatering of the pretreated sludge compared to pure hydrothermal pretreatment, and the higher the pH value was, the better the dewaterability of the pretreated sludge was. The conditions of 180 °C/30 min and 160 °C/60 min/pH = 10.0 (for hydrothermal and alkaline hydrothermal pretreatments, respectively) resulted in relatively good results in the theoretical energy balance, which were verified in the pilot-scale tests. Based on the data from the pilot tests, the alkaline hydrothermal process realized self-sufficiency in energy at the cost of a proper amount of CaO. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Stabilization of Pb(II) accumulated in biomass through phosphate-pretreated pyrolysis at low temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Li, Saijun; Zhang, Tao; Li, Jianfa, E-mail: ljf@usx.edu.cn; Shi, Lingna; Zhu, Xiaoxiao; Lü, Jinhong; Li, Yimin

    2017-02-15

    Highlights: • Phosphate-pretreated pyrolysis can stabilize Pb(II) accumulated in biomass. • More than 95% of Pb(II) in celery and wood biomass was stabilized. • Pb from biomass was almost totally retained in char. • Most Pb was transformed into phosphates according to XRD and SEM/EDX analyses. - Abstract: The remediation of heavy metal-contaminated soil and water using plant biomass is considered to be a green technological approach, although the harmless disposal of biomass accumulated with heavy metals remains a challenge. A potential solution to this problem explored in this work involves combining phosphate pretreatment with pyrolysis. Pb(II) was accumulated in celery biomass with superior sorption capacity and also in ordinary wood biomass through biosorption. The Pb(II)-impregnated biomass was then pretreated with phosphoric acid or calcium dihydrogen phosphate (CaP) and pyrolyzed at 350 or 450 °C. Pb(II) from biomass was in turn almost totally retained in chars, and the percentage of DTPA-extractable Pb(II) was reduced to less than 5% of total Pb(II) in chars through CaP pretreatment. Pb(II) stabilization was further confirmed through a sequential extraction test, which showed that more than 95% of Pb(II) was converted into stable species composed mainly of lead phosphates according to X-ray diffraction (XRD) and scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX) analyses. Overall, phosphate-pretreated pyrolysis can stabilize both Pb(II) and degradable biomass, so as to control efficiently the hazards of heavy metal-contaminated biomass.

  17. Pretreating lignocellulosic biomass by the concentrated phosphoric acid plus hydrogen peroxide (PHP) for enzymatic hydrolysis: evaluating the pretreatment flexibility on feedstocks and particle sizes.

    Science.gov (United States)

    Wang, Qing; Wang, Zhanghong; Shen, Fei; Hu, Jinguang; Sun, Fubao; Lin, Lili; Yang, Gang; Zhang, Yanzong; Deng, Shihuai

    2014-08-01

    In order to seek a high-efficient pretreatment path for converting lignocellulosic feedstocks to fermentable sugars by enzymatic hydrolysis, the concentrated H₃PO₄ plus H₂O₂ (PHP) was attempted to pretreat different lignocellulosic biomass for evaluating the pretreatment flexibility on feedstocks. Meanwhile, the responses of pretreatment to particle sizes were also evaluated. When the PHP-pretreatment was employed (final H₂O₂ and H₃PO₄ concentration of 1.77% and 80.0%), 71-96% lignin and more than 95% hemicellulose in various feedstocks (agricultural residues, hardwood, softwood, bamboo, and their mixture, and garden wastes mixture) can be removed. Consequently, more than 90% glucose conversion was uniformly achieved indicating PHP greatly improved the pretreatment flexibility to different feedstocks. Moreover, when wheat straw and oak chips were PHP-pretreated with different sizes, the average glucose conversion reached 94.9% and 100% with lower coefficient of variation (7.9% and 0.0%), which implied PHP-pretreatment can significantly weaken the negative effects of feedstock sizes on subsequent conversion. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. NON-POLLUTING METAL SURFACE FINISHING PRETREATMENT AND PRETREATMENT/CONVERSION COATING

    Science.gov (United States)

    Picklex, a proprietary formulation, is an alterantive to conventional metal surface pretreatments and is claimed not to produce waste or lower production or lower performance. A laboratory program was designed to evaluate Picklex in common, large scale, polluting surface finishin...

  19. Enzymatic saccharification of dilute acid pretreated saline crops for fermentable sugar production

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Yi; Zhang, Ruihong [Biological and Agricultural Engineering Department, University of California, Davis One Shields Avenue, Davis, CA 95616 (United States); Pan, Zhongli [Biological and Agricultural Engineering Department, University of California, Davis One Shields Avenue, Davis, CA 95616 (United States); Processed Foods Research Unit, USDA-ARS-WRRC, 800 Buchanan Street, Albany, CA 94710 (United States); Wang, Donghai [Biological and Agricultural Engineering Department, Kansas State University, Manhattan, KS 66506 (United States)

    2009-11-15

    Four saline crops [athel (Tamarix aphylla L), eucalyptus (Eucalyptus camaldulensis), Jose Tall Wheatgrass (Agropyron elongatum), and Creeping Wild Ryegrass (Leymus triticoides)] that are used in farms for salt uptake from soil and drainage irrigation water have the potential for fuel ethanol production because they don't take a large number of arable lands. Dilute sulfuric acid pretreatment and enzymatic hydrolysis were conducted to select the optimum pretreatment conditions and the best saline crop for further enzymatic hydrolysis research. The optimum dilute acid pretreatment conditions included T = 165 C, t = 8 min, and sulfuric acid concentration 1.4% (w/w). Creeping Wild Ryegrass was decided to be the best saline crop. Solid loading, cellulase and {beta}-glucosidase concentrations had significant effects on the enzymatic hydrolysis of dilute acid pretreated Creeping Wild Ryegrass. Glucose concentration increased by 36 mg/mL and enzymatic digestibility decreased by 20% when the solid loading increased from 4 to 12%. With 8% solid loading, enzymatic digestibility increased by over 30% with the increase of cellulase concentration from 5 to 15 FPU/g-cellulose. Under given cellulase concentration of 15 FPU/g-cellulose, 60% increase of enzymatic digestibility of pretreated Creeping Wild Ryegrass was obtained with the increase of {beta}-glucosidase concentration up to 15 CBU/g-cellulose. With a high solid loading of 10%, fed-batch operation generated 12% and 18% higher enzymatic digestibility and glucose concentration, respectively, than batch process. (author)

  20. Effect of steam pretreatment on oil palm empty fruit bunch for the production of sugars

    International Nuclear Information System (INIS)

    Shamsudin, Saleha; Md Shah, Umi Kalsom; Zainudin, Huzairi; Abd-Aziz, Suraini; Mustapa Kamal, Siti Mazlina; Shirai, Yoshihito; Hassan, Mohd Ali

    2012-01-01

    Lignocellulose into fuel ethanol is the most feasible conversion route strategy in terms of sustainability. Oil palm empty fruit bunch (EFB) generated from palm oil production is a huge source of cellulosic material and represents a cheap renewable feedstock which awaits further commercial exploitation. The purpose of this study was to investigate the feasibility of using steam at 0.28 MPa and 140 °C generated from the palm oil mill boiler as a pretreatment to enhance the digestibility of EFB for sugars production. The effects of steam pretreatment or autohydrolysis on chemical composition changes, polysaccharide conversion, sugar production and morphology alterations of four different types of EFB namely fresh EFB (EFB1), sterilized EFB (EFB2), shredded EFB (EFB3) and ground EFB (EFB4) were evaluated. In this study, the effects of steam pretreatment showed major alterations in the morphology of EFB as observed under the scanning electron microscope. Steam pretreated EFB2 was found to have the highest total conversion of 30% to sugars with 209 g kg −1 EFB. This production was 10.5 fold higher than for EFB1 and 1.6 fold and 1.7 fold higher than EFB3 and EFB4, respectively. The results suggested that pretreatment of EFB by autohydrolysis using steam from the mill boiler could be considered as being a suitable pretreatment process for the production of sugars. These sugars can be utilized as potential substrates for the production of various products such as fuel ethanol. -- Highlights: ► We investigate the feasibility of steam pretreatment to enhance digestibility of EFB. ► Steam pretreatment increased sugars to 3.4 fold and caused major alteration in EFB morphology under SEM. ► Autohydrolysis which does not require the addition of chemicals is an attractive pretreatment approach to EFB.

  1. Dilute alkali pretreatment of softwood pine: A biorefinery approach.

    Science.gov (United States)

    Safari, Ali; Karimi, Keikhosro; Shafiei, Marzieh

    2017-06-01

    Dilute alkali pretreatment was performed on softwood pine to maximize ethanol and biogas production via a biorefinery approach. Alkali pretreatments were performed with 0-2% w/v NaOH at 100-180°C for 1-5h. The liquid fraction of the pretreated substrates was subjected to anaerobic digestion. The solid fraction of the pretreatment was used for separate enzymatic hydrolysis and fermentation. High ethanol yields of 76.9‒78.0% were achieved by pretreatment with 2% (w/v) NaOH at 180°C. The highest biogas yield of 244mL/g volatile solid (at 25°C, 1bar) was achieved by the pretreatment with 1% (w/v) NaOH at 180°C. The highest gasoline equivalent (sum of ethanol and methane) of 197L per ton of pinewood and the lowest ethanol manufacturing cost of 0.75€/L was obtained after pretreatment with 1% NaOH at 180°C for 5h. The manufacturing cost of ethanol from untreated wood was 4.12€/L. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Improvement of municipal wastewater pretreatment by direct membrane filtration.

    Science.gov (United States)

    Nascimento, Thiago A; Mejía, Fanny R; Fdz-Polanco, Fernando; Peña Miranda, Mar

    2017-10-01

    The high content of particulate matter in municipal wastewater hinders the conventional anaerobic treatments at psychrophilic temperatures. The hydrolysis of the particulate chemical oxygen demand (pCOD) could be the limiting step under these conditions. Therefore, new pretreatments or improved conventional pretreatments are needed in order to separate pCOD. In this work, direct membrane filtration of municipal wastewater, using an ultrafiltration membrane, was investigated. This intensive pretreatment, which aims to separate soluble chemical oxygen demand (sCOD) and to concentrate pCOD, together with anaerobic treatments of both streams at psychrophilic and mesophilic conditions respectively, could be an alternative to the conventional activated sludge process. The obtained results show a removal yield of 24.9% of the total solids (TS) and 45% of total chemical oxygen demand (tCOD), obtaining a permeate free of suspended solids. This physical removal implies the accumulation of solids inside the membrane tank, reaching the values of 45.4 and 4.4 g/L of TS in the sedimentation and filtration sections, respectively. The membrane operated with filtration, backwashing cycles and continuous gas sparging, with a permeate flux predominantly around 10 L/(m 2  h). The results show the viability of the technology to concentrate pCOD and so to improve energy recovery from municipal wastewater.

  3. Scale-up and integration of alkaline hydrogen peroxide pretreatment, enzymatic hydrolysis, and ethanolic fermentation.

    Science.gov (United States)

    Banerjee, Goutami; Car, Suzana; Liu, Tongjun; Williams, Daniel L; Meza, Sarynna López; Walton, Jonathan D; Hodge, David B

    2012-04-01

    Alkaline hydrogen peroxide (AHP) has several attractive features as a pretreatment in the lignocellulosic biomass-to-ethanol pipeline. Here, the feasibility of scaling-up the AHP process and integrating it with enzymatic hydrolysis and fermentation was studied. Corn stover (1 kg) was subjected to AHP pretreatment, hydrolyzed enzymatically, and the resulting sugars fermented to ethanol. The AHP pretreatment was performed at 0.125 g H(2) O(2) /g biomass, 22°C, and atmospheric pressure for 48 h with periodic pH readjustment. The enzymatic hydrolysis was performed in the same reactor following pH neutralization of the biomass slurry and without washing. After 48 h, glucose and xylose yields were 75% and 71% of the theoretical maximum. Sterility was maintained during pretreatment and enzymatic hydrolysis without the use of antibiotics. During fermentation using a glucose- and xylose-utilizing strain of Saccharomyces cerevisiae, all of the Glc and 67% of the Xyl were consumed in 120 h. The final ethanol titer was 13.7 g/L. Treatment of the enzymatic hydrolysate with activated carbon prior to fermentation had little effect on Glc fermentation but markedly improved utilization of Xyl, presumably due to the removal of soluble aromatic inhibitors. The results indicate that AHP is readily scalable and can be integrated with enzyme hydrolysis and fermentation. Compared to other leading pretreatments for lignocellulosic biomass, AHP has potential advantages with regard to capital costs, process simplicity, feedstock handling, and compatibility with enzymatic deconstruction and fermentation. Biotechnol. Bioeng. 2012; 109:922-931. © 2011 Wiley Periodicals, Inc. Copyright © 2011 Wiley Periodicals, Inc.

  4. Investigating Individuals' Intention to be Involved in Knowledge Management Process

    OpenAIRE

    M. J.M. Razi; N. S.A. Karim

    2011-01-01

    Problem statement: Implementation of Knowledge Management (KM) process in organizations is considered as essential to be competitive in the present competitive world. Though the modern KM practices highly depend on technology, individuals (organizational members) intention to be involved in KM process plays a major role in the success. Hence, the evaluation of individuals intention is deemed as significant before the actual implementation of KM process in organizations. Nevertheless, inadequa...

  5. Testing of alkaline and enzymatic hydrolysis pretreatments for fat particles in slaughterhouse wastewater.

    Science.gov (United States)

    Masse, L; Kennedy, K J; Chou, S

    2001-04-01

    Four pretreatments to hydrolyse and/or reduce the size of fat particles in slaughterhouse wastewater (SHW) were tested: sodium hydroxide and three lipases of plant, bacterial and animal (pancreatic) origin. Hydrolysing agents and SHW containing between 2.5 and 3 g/l of fat particles were mixed at room temperature for 4 h. Additions of 5-400 meq NaOH/l did not increase soluble COD (SCOD) in SHW, but the average particle size was reduced to 73% +/- 7% of the initial average particle size (D(in)) at NaOH concentrations ranging from 150 to 300 meq/l. Pretreatment with pancreatic lipase PL-250 reduced the average particle size to a maximum of 60% +/- 3% of D(in). As D(in) was decreased from 359 to 68 microns, the enzyme concentration required to obtain the maximum particle size reduction increased from 200 to 1000 mg/l. A 4-h pretreatment with PL-250 also increased the free long-chain fatty acid (LCFA) concentration to a maximum of 15.5 mg/l, indicating some solubilization of the pork fat particles in SHW. SCOD was not significantly increased by the pretreatment, but SCOD was not found to be a good indicator of enzymatic lipolysis because of enzyme adsorption on the fat particle surface. Pancreatic lipase appeared more efficient with beef fat than pork fat, possibly because beef fat contains less polyunsaturated fatty acids than pork fat. The bacterial lipase LG-1000 was also efficient in reducing average fat particle size, but high doses (> 1000 mg/l) were required to obtain a significant reduction after 4 h of pretreatment. SCOD was not increased by pretreatment with LG-1000. No particle size reduction or changes in SCOD were noted after 4 h of pretreatment with the plant lipase EcoSystem Plus. It was concluded that PL-250 was the best pretreatment to hydrolyse fat particles in SHW. However, its impact on the efficiency of a downstream anaerobic digestion process remains to be tested.

  6. Economic Impact of NMMO Pretreatment on Ethanol and Biogas Production from Pinewood

    Science.gov (United States)

    Zilouei, Hamid; Taherzadeh, Mohammad J.

    2014-01-01

    Processes for ethanol and biogas (scenario 1) and biomethane (scenario 2) production from pinewood improved by N-methylmorpholine-N-oxide (NMMO) pretreatment were developed and simulated by Aspen plus. These processes were compared with two processes using steam explosion instead of NMMO pretreatment ethanol (scenario 3) and biomethane (scenario 4) production, and the economies of all processes were evaluated by Aspen Process Economic Analyzer. Gasoline equivalent prices of the products including 25% value added tax (VAT) and selling and distribution expenses for scenarios 1 to 4 were, respectively, 1.40, 1.20, 1.24, and 1.04 €/l, which are lower than gasoline price. The profitability indexes for scenarios 1 to 4 were 1.14, 0.93, 1.16, and 0.96, respectively. Despite the lower manufacturing costs of biomethane, the profitability indexes of these processes were lower than those of the bioethanol processes, because of higher capital requirements. The results showed that taxing rule is an effective parameter on the economy of the biofuels. The gasoline equivalent prices of the biofuels were 15–37% lower than gasoline; however, 37% of the gasoline price contributes to energy and carbon dioxide tax which are not included in the prices of biofuels based on the Swedish taxation rules. PMID:25276777

  7. Economic Impact of NMMO Pretreatment on Ethanol and Biogas Production from Pinewood

    Directory of Open Access Journals (Sweden)

    Marzieh Shafiei

    2014-01-01

    Full Text Available Processes for ethanol and biogas (scenario 1 and biomethane (scenario 2 production from pinewood improved by N-methylmorpholine-N-oxide (NMMO pretreatment were developed and simulated by Aspen plus. These processes were compared with two processes using steam explosion instead of NMMO pretreatment ethanol (scenario 3 and biomethane (scenario 4 production, and the economies of all processes were evaluated by Aspen Process Economic Analyzer. Gasoline equivalent prices of the products including 25% value added tax (VAT and selling and distribution expenses for scenarios 1 to 4 were, respectively, 1.40, 1.20, 1.24, and 1.04 €/l, which are lower than gasoline price. The profitability indexes for scenarios 1 to 4 were 1.14, 0.93, 1.16, and 0.96, respectively. Despite the lower manufacturing costs of biomethane, the profitability indexes of these processes were lower than those of the bioethanol processes, because of higher capital requirements. The results showed that taxing rule is an effective parameter on the economy of the biofuels. The gasoline equivalent prices of the biofuels were 15–37% lower than gasoline; however, 37% of the gasoline price contributes to energy and carbon dioxide tax which are not included in the prices of biofuels based on the Swedish taxation rules.

  8. Economic impact of NMMO pretreatment on ethanol and biogas production from pinewood.

    Science.gov (United States)

    Shafiei, Marzieh; Karimi, Keikhosro; Zilouei, Hamid; Taherzadeh, Mohammad J

    2014-01-01

    Processes for ethanol and biogas (scenario 1) and biomethane (scenario 2) production from pinewood improved by N-methylmorpholine-N-oxide (NMMO) pretreatment were developed and simulated by Aspen plus. These processes were compared with two processes using steam explosion instead of NMMO pretreatment ethanol (scenario 3) and biomethane (scenario 4) production, and the economies of all processes were evaluated by Aspen Process Economic Analyzer. Gasoline equivalent prices of the products including 25% value added tax (VAT) and selling and distribution expenses for scenarios 1 to 4 were, respectively, 1.40, 1.20, 1.24, and 1.04 €/l, which are lower than gasoline price. The profitability indexes for scenarios 1 to 4 were 1.14, 0.93, 1.16, and 0.96, respectively. Despite the lower manufacturing costs of biomethane, the profitability indexes of these processes were lower than those of the bioethanol processes, because of higher capital requirements. The results showed that taxing rule is an effective parameter on the economy of the biofuels. The gasoline equivalent prices of the biofuels were 15-37% lower than gasoline; however, 37% of the gasoline price contributes to energy and carbon dioxide tax which are not included in the prices of biofuels based on the Swedish taxation rules.

  9. Effects of SPORL and dilute acid pretreatment on substrate morphology, cell physical and chemical wall structures, and subsequent enzymatic hydrolysis of lodgepole pine.

    Science.gov (United States)

    Li, Xinping; Luo, Xiaolin; Li, Kecheng; Zhu, J Y; Fougere, J Dennis; Clarke, Kimberley

    2012-11-01

    The effects of pretreatment by dilute acid and sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) on substrate morphology, cell wall physical and chemical structures, along with the subsequent enzymatic hydrolysis of lodgepole pine substrate were investigated. FE-SEM and TEM images of substrate structural morphological changes showed that SPORL pretreatment resulted in fiber separation, where SPORL high pH (4.2) pretreatment exhibited better fiber separation than SPORL low pH (1.9) pretreatment. Dilute acid pretreatment produced very poor fiber separation, consisting mostly of fiber bundles. The removal of almost all hemicelluloses in the dilute acid pretreated substrate did not overcome recalcitrance to achieve a high cellulose conversion when lignin removal was limited. SPORL high pH pretreatment removed more lignin but less hemicellulose, while SPORL low pH pretreatment removed about the same amount of lignin and hemicelluloses in lodgepole pine substrates when compared with dilute acid pretreatment. Substrates pretreated with either SPORL process had a much higher cellulose conversion than those produced with dilute acid pretreatment. Lignin removal in addition to removal of hemicellulose in SPORL pretreatment plays an important role in improving the cellulose hydrolysis of the substrate.

  10. Silane pre-treatments on copper and aluminium

    International Nuclear Information System (INIS)

    Deflorian, F.; Rossi, S.; Fedrizzi, L.

    2006-01-01

    A large part of aluminium products are coated with an organic layer in order to improve the corrosion resistance. Copper surfaces are also sometimes protected with an organic coating to improve the durability or the aesthetic properties. Examples of industrial applications are household appliances and heat exchanger components. For these applications it is not rare to have the industrial need to treat at the same time components made of aluminium and copper. In order to extend the service life of the organic coated copper a specific surface pre-treatment is often required. Nevertheless, probably because of the limited market of this application, no specific pre-treatments for copper are industrially developed, with the exception of cleaning procedures, but simply extensions of existing pre-treatments optimised for other metals (aluminium, zinc) are used. The application of silane pre-treatments as adhesion promoters for organic coated metals is remarkably increasing in the last decade, because silanes offer very good performance together with high environmental compatibility. The idea is therefore to try to develop a specific silane based pre-treatment for copper. The starting point is the existing silane products for aluminium, optimising the composition and the application conditions (concentration, temperature, pH of the bath, etc.) in order to develop a high performance copper alloy pre-treatment increasing the protective properties and the adhesion of a successively applied organic coating. Moreover these pre-treatments could be used for aluminium alloys too and therefore could be suggested for multi-metals components. The deposits were analysed using FTIR spectroscopy and optical and electron microscopic observations. A careful electrochemical characterisation, mainly by electrochemical impedance spectroscopy measurements (EIS) was carried out to highlight the presence of silane and to evaluate the performance of the different deposits. In order to study an

  11. Effect of thermal pretreatment on the biogas production and microbial communities balance during anaerobic digestion of urban and industrial waste activated sludge.

    Science.gov (United States)

    Ennouri, Hajer; Miladi, Baligh; Diaz, Soraya Zahedi; Güelfo, Luis Alberto Fernández; Solera, Rosario; Hamdi, Moktar; Bouallagui, Hassib

    2016-08-01

    The effect of thermal pre-treatment on the microbial populations balance and biogas production was studied during anaerobic digestion of waste activated sludge (WAS) coming from urban (US: urban sludge) and industrial (IS: industrial sludge) wastewater treatment plants (WWTP). The highest biogas yields of 0.42l/gvolatile solid (VS) removed and 0.37l/gVS removed were obtained with urban and industrial sludge pre-treated at 120°C, respectively. Fluorescent in situ hybridization (FISH) was used to quantify the major Bacteria and Archaea groups. Compared to control trails without pretreatment, Archaea content increased from 34% to 86% and from 46% to 83% for pretreated IS and US, respectively. In fact, the thermal pre-treatment of WAS enhanced the growth of hydrogen-using methanogens (HUMs), which consume rapidly the H2 generated to allow the acetogenesis. Therefore, the stable and better performance of digesters was observed involving the balance and syntrophic associations between the different microbial populations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Influences of mechanical pretreatment on the non-biological treatment of municipal wastewater by forward osmosis.

    Science.gov (United States)

    Hey, Tobias; Zarebska, Agata; Bajraktari, Niada; Vogel, Jörg; Hélix-Nielsen, Claus; la Cour Jansen, Jes; Jönsson, Karin

    2017-09-01

    Municipal wastewater treatment involves mechanical, biological and chemical treatment steps for protecting the environment from adverse effects. The biological treatment step consumes the most energy and can create greenhouse gases. This study investigates municipal wastewater treatment without the biological treatment step, including the effects of different pretreatment configurations, for example, direct membrane filtration before forward osmosis. Forward osmosis was tested using raw wastewater and wastewater subjected to different types of mechanical pretreatment, for example, microsieving and microfiltration permeation, as a potential technology for municipal wastewater treatment. Forward osmosis was performed using Aquaporin Inside™ and Hydration Technologies Inc. (HTI) membranes with NaCl as the draw solution. Both types of forward osmosis membranes were tested in parallel for the different types of pretreated feed and evaluated in terms of water flux and solute rejection, that is, biochemical oxygen demand (BOD 7 ) and total and soluble phosphorus contents. The Aquaporin and HTI membranes achieved a stable water flux with rejection rates of more than 96% for BOD 7 and total and soluble phosphorus, regardless of the type of mechanical pretreated wastewater considered. This result indicates that forward osmosis membranes can tolerate exposure to municipal waste water and that the permeate can fulfil the Swedish discharge limits.

  13. Eco-friendly process combining physical-chemical and biological technics for the fermented dairy products waste pretreatment and reuse.

    Science.gov (United States)

    Kasmi, Mariam; Hamdi, Moktar; Trabelsi, Ismail

    2017-01-01

    Residual fermented dairy products resulting from process defects or from expired shelf life products are considered as waste. Thus, dairies wastewater treatment plants (WWTP) suffer high input effluents polluting load. In this study, fermented residuals separation from the plant wastewater is proposed. In the aim to meet the municipal WWTP input limits, a pretreatment combining physical-chemical and biological processes was investigated to reduce residual fermented dairy products polluting effect. Yoghurt (Y) and fermented milk products (RL) were considered. Raw samples chemical oxygen demand (COD) values were assessed at 152 and 246 g.L -1 for Y and RL products, respectively. Following the thermal coagulation, maximum removal rates were recorded at 80 °C. Resulting whey stabilization contributed to the removal rates enhance to reach 72% and 87% for Y and RL samples; respectively. Residual whey sugar content was fermented using Candida strains. Bacterial growth and strains degrading potential were discussed. C. krusei strain achieved the most important removal rates of 78% and 85% with Y and RL medium, respectively. Global COD removal rates exceeded 93%.

  14. Removal of Water-Soluble Extractives Improves the Enzymatic Digestibility of Steam-Pretreated Softwood Barks.

    Science.gov (United States)

    Frankó, Balázs; Carlqvist, Karin; Galbe, Mats; Lidén, Gunnar; Wallberg, Ola

    2018-02-01

    Softwood bark contains a large amounts of extractives-i.e., soluble lipophilic (such as resin acids) and hydrophilic components (phenolic compounds, stilbenes). The effects of the partial removal of water-soluble extractives before acid-catalyzed steam pretreatment on enzymatic digestibility were assessed for two softwood barks-Norway spruce and Scots pine. A simple hot water extraction step removed more than half of the water-soluble extractives from the barks, which improved the enzymatic digestibility of both steam-pretreated materials. This effect was more pronounced for the spruce than the pine bark, as evidenced by the 30 and 11% glucose yield improvement, respectively, in the enzymatic digestibility. Furthermore, analysis of the chemical composition showed that the acid-insoluble lignin content of the pretreated materials decreased when water-soluble extractives were removed prior to steam pretreatment. This can be explained by a decreased formation of water-insoluble "pseudo-lignin" from water-soluble bark phenolics during the acid-catalyzed pretreatment, which otherwise results in distorted lignin analysis and may also contribute to the impaired enzymatic digestibility of the barks. Thus, this study advocates the removal of extractives as the first step in the processing of bark or bark-rich materials in a sugar platform biorefinery.

  15. Changes in lignocellulosic supramolecular and ultrastructure during dilute acid pretreatment of Populus and switchgrass

    International Nuclear Information System (INIS)

    Foston, Marcus; Ragauskas, Art J.

    2010-01-01

    Dilute acid pretreatment (DAP) is commonly employed prior to enzymatic deconstruction of cellulose to increase overall sugar and subsequent ethanol yields from downstream bioconversion processes. Typically optimization of pretreatment is evaluated by determining hemicellulose removal, subsequent reactivity towards enzymatic deconstruction, and recoverable polysaccharide yields. In this study, the affect of DAP on the supramolecular and ultrastructure of lignocellulosic biomass was evaluated. A series of dilute acidic pretreatments, employing ∼0.10-0.20 mol/m 3 H 2 SO 4 at ∼160-180 o C, for varying residence times were conducted on both Populus and switchgrass samples. The untreated and pretreated biomass samples were characterized by carbohydrate and lignin analysis, gel permeation chromatography (GPC) and 13 C cross polarization magic angle spinning (CPMAS) NMR spectroscopy. GPC analysis shows a reduction in the molecular weight of cellulose and change in its polydispersity index (PDI) with increasing residence time, indicating that pretreatment is actually degrading the cellulose chains. 13 C CPMAS and non-linear line-fitting of the C 4 region in the carbon spectrum of the isolated cellulose not only showed that the crystallinity index increases with residence time, but that the lateral fibril dimension (LFD) and lateral fibril aggregate dimension (LFAD) increase as well.

  16. Structural changes of corn stover lignin during acid pretreatment.

    Science.gov (United States)

    Moxley, Geoffrey; Gaspar, Armindo Ribeiro; Higgins, Don; Xu, Hui

    2012-09-01

    In this study, raw corn stover was subjected to dilute acid pretreatments over a range of severities under conditions similar to those identified by the National Renewable Energy Laboratory (NREL) in their techno-economic analysis of biochemical conversion of corn stover to ethanol. The pretreated corn stover then underwent enzymatic hydrolysis with yields above 70 % at moderate enzyme loading conditions. The enzyme exhausted lignin residues were characterized by ³¹P NMR spectroscopy and functional moieties quantified and correlated to enzymatic hydrolysis yields. Results from this study indicated that both xylan solubilization and lignin degradation are important for improving the enzyme accessibility and digestibility of dilute acid pretreated corn stover. At lower pretreatment temperatures, there is a good correlation between xylan solubilization and cellulose accessibility. At higher pretreatment temperatures, lignin degradation correlated better with cellulose accessibility, represented by the increase in phenolic groups. During acid pretreatment, the ratio of syringyl/guaiacyl functional groups also gradually changed from less than 1 to greater than 1 with the increase in pretreatment temperature. This implies that more syringyl units are released from lignin depolymerization of aryl ether linkages than guaiacyl units. The condensed phenolic units are also correlated with the increase in pretreatment temperature up to 180 °C, beyond which point condensation reactions may overtake the hydrolysis of aryl ether linkages as the dominant reactions of lignin, thus leading to decreased cellulose accessibility.

  17. Bioconversion of different sizes of microcrystalline cellulose pretreated by microwave irradiation with/without NaOH

    International Nuclear Information System (INIS)

    Peng, Huadong; Chen, Hongzhang; Qu, Yongshui; Li, Hongqiang; Xu, Jian

    2014-01-01

    Highlights: • High concentration of alkali or temperature was necessary in cellulose degradation. • Effects of alkali pretreatment could be enhanced with the addition of microwave irradiation. • The structures diversities of microcrystalline cellulose were eliminated in the fermentation. • The significance of particle size and treat condition varied with reaction time. - Abstract: The process of microwave irradiation (MWI) pretreatment on microcrystalline cellulose (MCC) with different sizes with/without NaOH was investigated on the variation of the ratio of degradated solid residue (R DS ), particle size, crystallinity index (CrI), crystallite size (Sc) and specific surface area (SSA). High concentration of alkali or high temperature was necessary in dissolving or decomposing the cellulose. Appropriate pretreatment severity eliminated the effects of structural diversities in feedstocks, which led to convergence in the ethanol fermentation. After the reaction proceeded to 120 h, the samples could be converted to glucose completely and the highest ethanol yield of the theoretical was 58.91% for all the samples pretreated by the combined treatment of MWI and NaOH. In addition, the statistical analysis implied that when reaction time got to 24 h, particle size and pretreatment condition affected much more significant than other factors

  18. Detoxification of Corncob Acid Hydrolysate with SAA Pretreatment and Xylitol Production by Immobilized Candida tropicalis

    Science.gov (United States)

    Deng, Li-Hong; Tang, Yong; Liu, Yun

    2014-01-01

    Xylitol fermentation production from corncob acid hydrolysate has become an attractive and promising process. However, corncob acid hydrolysate cannot be directly used as fermentation substrate owing to various inhibitors. In this work, soaking in aqueous ammonia (SAA) pretreatment was employed to reduce the inhibitors in acid hydrolysate. After detoxification, the corncob acid hydrolysate was fermented by immobilized Candida tropicalis cell to produce xylitol. Results revealed that SAA pretreatment showed high delignification and efficient removal of acetyl group compounds without effect on cellulose and xylan content. Acetic acid was completely removed, and the content of phenolic compounds was reduced by 80%. Furthermore, kinetic behaviors of xylitol production by immobilized C. tropicalis cell were elucidated from corncob acid hydrolysate detoxified with SAA pretreatment and two-step adsorption method, respectively. The immobilized C. tropicalis cell showed higher productivity efficiency using the corncob acid hydrolysate as fermentation substrate after detoxification with SAA pretreatment than by two-step adsorption method in the five successive batch fermentation rounds. After the fifth round fermentation, about 60 g xylitol/L fermentation substrate was obtained for SAA pretreatment detoxification, while about 30 g xylitol/L fermentation substrate was obtained for two-step adsorption detoxification. PMID:25133211

  19. Techno-economical study of biogas production improved by steam explosion pretreatment.

    Science.gov (United States)

    Shafiei, Marzieh; Kabir, Maryam M; Zilouei, Hamid; Sárvári Horváth, Ilona; Karimi, Keikhosro

    2013-11-01

    Economic feasibility of steam explosion pretreatment for improvement of biogas production from wheat straw and paper tube residuals was investigated. The process was simulated by Aspen plus ®, and the economical feasibility of five different plant capacities was studied by Aspen Process Economic Analyzer. Total project investment of a plant using paper tube residuals or wheat straw was 63.9 or 61.8 million Euros, respectively. The manufacturing cost of raw biogas for these two feedstocks was calculated to 0.36 or 0.48 €/m(3) of methane, respectively. Applying steam explosion pretreatment resulted in 13% higher total capital investment while significantly improved the economy of the biogas plant and decreased the manufacturing cost of methane by 36%. The sensitivity analysis showed that 5% improvement in the methane yield and 20% decrease in the raw material price resulted in 5.5% and 8% decrease in the manufacturing cost of methane, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Understanding changes in cellulose crystalline structure of lignocellulosic biomass during ionic liquid pretreatment by XRD.

    Science.gov (United States)

    Zhang, Jiafu; Wang, Yixun; Zhang, Liye; Zhang, Ruihong; Liu, Guangqing; Cheng, Gang

    2014-01-01

    X-ray diffraction (XRD) was used to understand the interactions of cellulose in lignocellulosic biomass with ionic liquids (ILs). The experiment was designed in such a way that the process of swelling and solubilization of crystalline cellulose in plant cell walls was followed by XRD. Three different feedstocks, switchgrass, corn stover and rice husk, were pretreated using 1-butyl-3-methylimidazolium acetate ([C4mim][OAc]) at temperatures of 50-130°C for 6h. At a 5 wt.% biomass loading, increasing pretreatment temperature led to a drop in biomass crystallinity index (CrI), which was due to swelling of crystalline cellulose. After most of the crystalline cellulose was swollen with IL molecules, a low-order structure was found in the pretreated samples. Upon further increasing temperature, cellulose II structure started to form in the pretreated biomass samples as a result of solubilization of cellulose in [C4mim][OAc] and subsequent regeneration. Copyright © 2013 Elsevier Ltd. All rights reserved.