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Sample records for continuous biohydrogen production

  1. Continuous biohydrogen production from waste bread by anaerobic sludge.

    Science.gov (United States)

    Han, Wei; Huang, Jingang; Zhao, Hongting; Li, Yongfeng

    2016-07-01

    In this study, continuous biohydrogen production from waste bread by anaerobic sludge was performed. The waste bread was first hydrolyzed by the crude enzymes which were generated by Aspergillus awamori and Aspergillus oryzae via solid-state fermentation. It was observed that 49.78g/L glucose and 284.12mg/L free amino nitrogen could be produced with waste bread mass ratio of 15% (w/v). The waste bread hydrolysate was then used for biohydrogen production by anaerobic sludge in a continuous stirred tank reactor (CSTR). The optimal hydrogen production rate of 7.4L/(Ld) was achieved at chemical oxygen demand (COD) of 6000mg/L. According to the results obtained from this study, 1g waste bread could generate 0.332g glucose which could be further utilized to produce 109.5mL hydrogen. This is the first study which reports continuous biohydrogen production from waste bread by anaerobic sludge. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Biohydrogen production from enzymatic hydrolysis of food waste in batch and continuous systems

    OpenAIRE

    Wei Han; Yingting Yan; Yiwen Shi; Jingjing Gu; Junhong Tang; Hongting Zhao

    2016-01-01

    In this study, the feasibility of biohydrogen production from enzymatic hydrolysis of food waste was investigated. Food waste (solid-to-liquid ratio of 10%, w/v) was first hydrolyzed by commercial glucoamylase to release glucose (24.35?g/L) in the food waste hydrolysate. Then, the obtained food waste hydrolysate was used as substrate for biohydrogen production in the batch and continuous (continuous stirred tank reactor, CSTR) systems. It was observed that the maximum cumulative hydrogen prod...

  3. CFD optimization of continuous stirred-tank (CSTR) reactor for biohydrogen production.

    Science.gov (United States)

    Ding, Jie; Wang, Xu; Zhou, Xue-Fei; Ren, Nan-Qi; Guo, Wan-Qian

    2010-09-01

    There has been little work on the optimal configuration of biohydrogen production reactors. This paper describes three-dimensional computational fluid dynamics (CFD) simulations of gas-liquid flow in a laboratory-scale continuous stirred-tank reactor used for biohydrogen production. To evaluate the role of hydrodynamics in reactor design and optimize the reactor configuration, an optimized impeller design has been constructed and validated with CFD simulations of the normal and optimized impeller over a range of speeds and the numerical results were also validated by examination of residence time distribution. By integrating the CFD simulation with an ethanol-type fermentation process experiment, it was shown that impellers with different type and speed generated different flow patterns, and hence offered different efficiencies for biohydrogen production. The hydrodynamic behavior of the optimized impeller at speeds between 50 and 70 rev/min is most suited for economical biohydrogen production. Copyright 2010 Elsevier Ltd. All rights reserved.

  4. Critical assessment of anaerobic processes for continuous biohydrogen production from organic wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Show, Kuan-Yeow [Faculty of Engineering and Green Technology, University Tunku Abdul Rahman, Jalan University, Bandar Barat, 31900 Kampar, Perak (Malaysia); Zhang, Zhen-Peng [Beijing Enterprises Water Group Limited, BLK 25, No. 3 Minzhuang Road, Beijing 100195 (China); Tay, Joo-Hwa [School of Civil and Environmental Engineering, Nanyang Technological University, Nanyang Avenue (Singapore); Liang, David Tee [Institute of Environmental Science and Engineering, Nanyang Technological University (Singapore); Lee, Duu-Jong [Department of Chemical Engineering, National Taiwan University, Taipei (China); Ren, Nanqi; Wang, Aijie [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China)

    2010-12-15

    Production of biohydrogen using dark fermentation has received much attention owing to the fact that hydrogen can be generated from renewable organics including waste materials. The key to successful application of anaerobic fermentation is to uncouple the liquid retention time and the biomass retention time in the reactor system. Various reactor designs based on biomass retention within the reactor system have been developed. This paper presents our research work on bioreactor designs and operation for biohydrogen production. Comparisons between immobilized-cell systems and suspended-cell systems based on biomass growth in the forms of granule, biofilm and flocs were made. Reactor configurations including column- and tank-based reactors were also assessed. Experimental results indicated that formation of granules or biofilms substantially enhanced biomass retention which was found to be proportional to the hydrogen production rate. Rapid hydrogen-producing culture growth and high organic loading rate might limit the application of biofilm biohydrogen production, since excessive growth of fermentative biomass would result in washout of support carrier. It follows that column-based granular sludge process is a preferred choice of process for continuous biohydrogen production from organic wastewater, indicating maximum hydrogen yield of 1.7 mol-H{sub 2}/mol-glucose and hydrogen production rate of 6.8 L-H{sub 2}/L-reactor h. (author)

  5. Bio-hydrogen production from molasses by anaerobic fermentation in continuous stirred tank reactor

    Science.gov (United States)

    Han, Wei; Li, Yong-feng; Chen, Hong; Deng, Jie-xuan; Yang, Chuan-ping

    2010-11-01

    A study of bio-hydrogen production was performed in a continuous flow anaerobic fermentation reactor (with an available volume of 5.4 L). The continuous stirred tank reactor (CSTR) for bio-hydrogen production was operated under the organic loading rates (OLR) of 8-32 kg COD/m3 reactor/d (COD: chemical oxygen demand) with molasses as the substrate. The maximum hydrogen production yield of 8.19 L/d was obtained in the reactor with the OLR increased from 8 kg COD/m3 reactor/d to 24 kg COD/m3 d. However, the hydrogen production and volatile fatty acids (VFAs) drastically decreased at an OLR of 32 kg COD/m3 reactor/d. Ethanoi, acetic, butyric and propionic were the main liquid fermentation products with the percentages of 31%, 24%, 20% and 18%, which formed the mixed-type fermentation.

  6. Biohydrogen production from enzymatic hydrolysis of food waste in batch and continuous systems

    Science.gov (United States)

    Han, Wei; Yan, Yingting; Shi, Yiwen; Gu, Jingjing; Tang, Junhong; Zhao, Hongting

    2016-01-01

    In this study, the feasibility of biohydrogen production from enzymatic hydrolysis of food waste was investigated. Food waste (solid-to-liquid ratio of 10%, w/v) was first hydrolyzed by commercial glucoamylase to release glucose (24.35 g/L) in the food waste hydrolysate. Then, the obtained food waste hydrolysate was used as substrate for biohydrogen production in the batch and continuous (continuous stirred tank reactor, CSTR) systems. It was observed that the maximum cumulative hydrogen production of 5850 mL was achieved with a yield of 245.7 mL hydrogen/g glucose (1.97 mol hydrogen/mol glucose) in the batch system. In the continuous system, the effect of hydraulic retention time (HRT) on biohydrogen production from food waste hydrolysate was investigated. The optimal HRT obtained from this study was 6 h with the highest hydrogen production rate of 8.02 mmol/(h·L). Ethanol and acetate were the major soluble microbial products with low propionate production at all HRTs. Enzymatic hydrolysis of food waste could effectively accelerate hydrolysis speed, improve substrate utilization rate and increase hydrogen yield. PMID:27910937

  7. Acclimatization Study for Biohydrogen Production from Palm Oil Mill Effluent (POME) in Continuous-flow System

    Science.gov (United States)

    Idris, N.; Lutpi, N. A.; Wong, Y. S.; Tengku Izhar, T. N.

    2018-03-01

    This research aims to study the acclimatization phase for biohydrogen production from palm oil mill effluent (POME) by adapting the microorganism to the new environment in continuous-flow system of thermophilic bioreactor. The thermophilic fermentation was continuously loaded with 0.4 L/day of raw POME for 35 days to acclimatize the microorganism until a steady state of biohydrogen production was obtained. The significance effect of acclimatization phase on parameter such as pH, microbial growth, chemical oxygen demand (COD), and alkalinity were also studied besides the production of biogas. This study had found that the thermophilic bioreactor reach its steady state with 1960 mL/d of biogas produced, which consist of 894 ppm of hydrogen composition.

  8. Biohydrogen production from waste bread in a continuous stirred tank reactor: A techno-economic analysis.

    Science.gov (United States)

    Han, Wei; Hu, Yun Yi; Li, Shi Yi; Li, Fei Fei; Tang, Jun Hong

    2016-12-01

    Biohydrogen production from waste bread in a continuous stirred tank reactor (CSTR) was techno-economically assessed. The treating capacity of the H 2 -producing plant was assumed to be 2 ton waste bread per day with lifetime of 10years. Aspen Plus was used to simulate the mass and energy balance of the plant. The total capital investment (TCI), total annual production cost (TAPC) and annual revenue of the plant were USD931020, USD299746/year and USD639920/year, respectively. The unit hydrogen production cost was USD1.34/m 3 H 2 (or USD14.89/kg H 2 ). The payback period and net present value (NPV) of the plant were 4.8years and USD1266654, respectively. Hydrogen price and operators cost were the most important variables on the NPV. It was concluded that biohydrogen production from waste bread in the CSTR was feasible for practical application. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Continuous thermophilic biohydrogen production in packed bed reactor

    International Nuclear Information System (INIS)

    Roy, Shantonu; Vishnuvardhan, M.; Das, Debabrata

    2014-01-01

    Highlights: • Continuous H 2 production in whole cell immobilized system was compared with CSTR. • Suitability of environment friendly support matrix for immobilization of whole cells was explored. • Pack bed reactor showed higher stability as compared to CSTR at lower HRTs. • Flow cytometry study showed the influence of recycle ratio on viability of cells. • Novel approach to find out the effect of NADH/NAD + ratio during H 2 production. - Abstract: The present research work deals with the performance of packed bed reactor for continuous H 2 production using cane molasses as a carbon source. Maximum H 2 production rate of 1.7 L L −1 h −1 was observed at a dilution rate and recycle ratio of 0.8 h −1 and 0.6, respectively which was corresponding to the lowest NADH/NAD + ratio. This suggests that the utilization of NADH pool for H 2 and metabolite production might lead to decrement in NADH/NAD + ratio. Thus NADH/NAD + ratio show inverse relation with hydrogen production. The substrate degradation kinetics was investigated as a function of flow rate considering the external film diffusion model. At a flow rate of 245 mL h −1 , the contribution of external film mass transfer coefficient and first order substrate degradation constant were 55.4% and 44.6% respectively. Recycle ratio of 0.6 improved the hydrogen production rates by 9%. The viable cell count was directly proportional to the recycle ratio (within the range 0.1–0.6). Taguchi design showed the significant influence of the feed pH on continuous H 2 production followed by dilution rate and recycle ratio. Thus environmentally friendly and cheaper solid matrix like coconut coir could be efficiently used for thermophilic continuous hydrogen production

  10. The operation characteristics of biohydrogen production in continuous stirred tank reactor with molasses

    Energy Technology Data Exchange (ETDEWEB)

    Hong, C.; Wei, H.; Jie-xuan, D.; Xin, Y.; Chuan-ping, Y. [Northeast Forestry Univ., Harbin (China). School of Forestry; Li, Y.F. [Northeast Forestry Univ., Harbin (China). School of Forestry; Shanghai Univ. Engineering, Shanghai (China). College of Chemistry and Chemical Engineering

    2010-07-01

    The anaerobic fermentation biohydrogen production in a continuous stirred tank reactor (CSTR) was investigated as a means for treating molasses wastewater. The research demonstrated that the reactor has the capacity of continuously producing hydrogen in an initial biomass (as volatile suspension solids) of 17.74 g/L, temperature of approximately 35 degrees Celsius, hydraulic retention time of 6 hours. The reactor could begin the ethanol-type fermentation in 12 days and realize stable hydrogen production. The study also showed that the CSTR reactor has a favourable stability even with an organic shock loading. The hydrogen yield and chemical oxygen demand (COD) increased, as did the hydrogen content.

  11. Thermophilic Biohydrogen Production

    DEFF Research Database (Denmark)

    Karakashev, Dimitar Borisov; Angelidaki, Irini

    2011-01-01

    Dark fermentative hydrogen production at thermophilic conditions is attractive process for biofuel production. From thermodynamic point of view, higher temperatures favor biohydrogen production. Highest hydrogen yields are always associated with acetate, or with mixed acetate- butyrate type...... fermentation. On the contrary the hydrogen yield decreases, with increasing concentrations of lactate, ethanol or propionate. Major factors affecting dark fermentative biohydrogen production are organic loading rate (OLR), pH, hydraulic retention time (HRT), dissolved hydrogen and dissolved carbon dioxide...... concentrations, and soluble metabolic profile (SMP). A number of thermophilic and extreme thermophilic cultures (pure and mixed) have been studied for biohydrogen production from different feedstocks - pure substrates and waste/wastewaters. Variety of process technologies (operational conditions...

  12. Continuous biohydrogen production using cheese whey: Improving the hydrogen production rate

    Energy Technology Data Exchange (ETDEWEB)

    Davila-Vazquez, Gustavo; Cota-Navarro, Ciria Berenice; Razo-Flores, Elias [Division de Ciencias Ambientales, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la Presa San Jose 2055, Lomas 4a seccion, C.P. 78216, San Luis Potosi, S.L.P (Mexico); Rosales-Colunga, Luis Manuel; de Leon-Rodriguez, Antonio [Division de Biologia Molecular, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la Presa San Jose 2055, Lomas 4a seccion, C.P. 78216, San Luis Potosi, S.L.P (Mexico)

    2009-05-15

    Due to the renewed interest in finding sustainable fuels or energy carriers, biohydrogen (Bio-H{sub 2}) from biomass is a promising alternative. Fermentative Bio-H{sub 2} production was studied in a continuous stirred tank reactor (CSTR) operated during 65.6 d with cheese whey (CW) as substrate. Three hydraulic retention times (HRTs) were tested (10, 6 and 4 h) and the highest volumetric hydrogen production rate (VHPR) was attained with HRT of 6 h. Therefore, four organic loading rates (OLRs) at a fixed HRT of 6 h were tested thereafter, being: 92.4, 115.5, 138.6 and 184.4 g lactose/L/d. The highest VHPR (46.61 mmol H{sub 2}/L/h) and hydrogen molar yield (HMY) of 2.8 mol H{sub 2}/mol lactose were found at an OLR of 138.6 g lactose/L/d; a sharp fall in VHPR occurred at an OLR of 184.4 g lactose/L/d. Butyric, propionic and acetic acids were the main soluble metabolites found, with butyric-to-acetic ratios ranging from 1.0 to 2.4. Bacterial community was identified by partial sequence analysis of the 16S rRNA and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The results showed that at HRT of 10 h and 6 h were dominated by the Clostridium genus. The VHPR attained in this study is the highest reported value for a CSTR system using CW as substrate with anaerobic sludge as inoculum and represents a 33-fold increase compared to a previous study. Thus, it was demonstrated that continuous fermentative Bio-H{sub 2} production from CW can be significantly enhanced by an appropriate selection of parameters such as HRT and OLR. Enhancements in VHPR are significant because it is a critical parameter to determine the full-scale practical application of fermentation technologies that will be used for sustainable and clean energy generation. (author)

  13. Continuous biohydrogen production from fruit wastewater at low pH conditions.

    Science.gov (United States)

    Diamantis, Vasileios; Khan, Abid; Ntougias, Spyridon; Stamatelatou, Katerina; Kapagiannidis, Anastasios G; Aivasidis, Alexander

    2013-07-01

    Biohydrogen production from a simulated fruit wastewater (soluble COD = 3.17 ± 0.10 g L⁻¹) was carried out in a continuous stirred tank reactor (CSTR) of 2 L operational volume without biomass inoculation, heat pre-treatment or pH adjustment, resulting in a low operational pH (3.75 ± 0.09). The hydraulic retention time (HRT) varied from 15 to 5 h. A strong negative correlation (p CSTR was operated under the same HRT. The biogas hydrogen content was estimated as high as 55.8 ± 2.3 % and 55.4 ± 2.5 % at 25 and 30 °C, respectively. The main fermentation end products were acetic and butyric acids, followed by ethanol. Significant differences (p CSTR at 25 or 30 °C were identified for butyric acid at almost all HRTs examined. Simulation of the acidogenesis process in the CSTR (based on COD and carbon balances) indicated the possible metabolic compounds produced at 25 and 30 °C reactions and provided an adequate fit of the experimental data.

  14. Organic loading rates affect composition of soil-derived bacterial communities during continuous, fermentative biohydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Yonghua; Bruns, Mary Ann [Department of Crop and Soil Sciences, The Pennsylvania State University, University Park, PA 16802 (United States); Zhang, Husen; Salerno, Michael; Logan, Bruce E. [Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, PA 16802 (United States)

    2008-11-15

    Bacterial community composition during steady-state, fermentative H{sub 2} production was compared across a range of organic loading rates (OLRs) of 0.5-19 g COD l{sup -1} h{sup -1} in a 2-l continuous flow reactor at 30 C. The varied OLRs were achieved with glucose concentrations of 2.5-10 g l{sup -1} and hydraulic retention times of 1-10 h. The synthetic wastewater feed was amended with L-cysteine and maintained at a pH of 5.5. For each run at a given glucose concentration, the reactor was inoculated with an aliquot of well-mixed agricultural topsoil that had been heat-treated to reduce numbers of vegetative cells. At OLRs less than 2 g COD l{sup -1} h{sup -1}, DNA sequences from ribosomal RNA intergenic spacer analysis profiles revealed more diverse and variable populations (Selenomonas, Enterobacter, and Clostridium spp.) than were observed above 2 g COD l{sup -1} h{sup -1} (Clostridium spp. only). An isolate, LYH1, was cultured from a reactor sample (10 g glucose l{sup -1} at a 10-h HRT) on medium containing L-cysteine. In confirming H{sub 2} production by LYH1 in liquid batch culture, lag periods for H{sub 2} production in the presence and absence of L-cysteine were 5 and 50 h, respectively. The 16S rRNA gene sequence of LYH1 indicated that the isolate was a Clostridium sp. affiliated with RNA subcluster Ic, with >99% similarity to Clostridium sp. FRB1. In fluorescent in situ hybridization tests, an oligonucleotide probe complementary to the 16S rRNA of LYH1 hybridized with 90% of cells observed at an OLR of 2 g COD h{sup -1}, compared to 26% of cells at an OLR of 0.5 g COD l{sup -1} h{sup -1}. An OLR of 2 g COD l{sup -1} h{sup -1} appeared to be a critical threshold above which clostridia were better able to outcompete Enterobacteriaceae and other organisms in the mixed soil inoculum. Our results are discussed in light of other biohydrogen studies employing pure cultures and mixed inocula. (author)

  15. Performance of continuous stirred tank reactor (CSTR) on fermentative biohydrogen production from melon waste

    Science.gov (United States)

    Cahyari, K.; Sarto; Syamsiah, S.; Prasetya, A.

    2016-11-01

    This research was meant to investigate performance of continuous stirred tank reactor (CSTR) as bioreactor for producing biohydrogen from melon waste through dark fermentation method. Melon waste are commonly generated from agricultural processing stages i.e. cultivation, post-harvesting, industrial processing, and transportation. It accounted for more than 50% of total harvested fruit. Feedstock of melon waste was fed regularly to CSTR according to organic loading rate at value 1.2 - 3.6 g VS/ (l.d). Optimum condition was achieved at OLR 2.4 g VS/ (l.d) with the highest total gas volume 196 ml STP. Implication of higher OLR value is reduction of total gas volume due to accumulation of acids (pH 4.0), and lower substrate volatile solid removal. In summary, application of this method might valorize melon waste and generates renewable energy sources.

  16. Comparison of biohydrogen production processes

    International Nuclear Information System (INIS)

    Manish, S.; Banerjee, Rangan

    2008-01-01

    For hydrogen to be a viable energy carrier, it is important to develop hydrogen generation routes that are renewable like biohydrogen. Hydrogen can be produced biologically by biophotolysis (direct and indirect), photo-fermentation and dark-fermentation or by combination of these processes (such as integration of dark- and photo-fermentation (two-stage process), or biocatalyzed electrolysis, etc.). However, production of hydrogen by these methods at commercial level is not reported in the literature and challenges regarding the process scale up remain. In this scenario net energy analysis (NEA) can provide a tool for establishing the viability of different methods before scaling up. The analysis can also be used to set targets for various process and design parameters for bio-hydrogen production. In this paper, four biohydrogen production processes (dark-fermentation, photo-fermentation, two-stage process and biocatalyzed electrolysis) utilizing sugarcane juice as the carbon source, are compared with base case method steam methane reforming (SMR) on the basis of net energy ratio, energy efficiency and greenhouse gas (GHG) emissions. It was found that when by-products are not considered, the efficiencies of biological hydrogen processes are lower than that of SMR. However, these processes reduce GHG emissions and non-renewable energy use by 57-73% and 65-79%, respectively, as compared to the SMR process. Efficiencies of biohydrogen processes increase significantly when by-products are considered hence by-products removal and utilization is an important issue in biological hydrogen production. (author)

  17. Biohydrogen and Bioethanol Production from Biodiesel-Based Glycerol by Enterobacter aerogenes in a Continuous Stir Tank Reactor

    Directory of Open Access Journals (Sweden)

    Rujira Jitrwung

    2015-05-01

    Full Text Available Crude glycerol from the biodiesel manufacturing process is being produced in increasing quantities due to the expanding number of biodiesel plants. It has been previously shown that, in batch mode, semi-anaerobic fermentation of crude glycerol by Enterobacter aerogenes can produce biohydrogen and bioethanol simultaneously. The present study demonstrated the possible scaling-up of this process from small batches performed in small bottles to a 3.6-L continuous stir tank reactor (CSTR. Fresh feed rate, liquid recycling, pH, mixing speed, glycerol concentration, and waste recycling were optimized for biohydrogen and bioethanol production. Results confirmed that E. aerogenes uses small amounts of oxygen under semi-anaerobic conditions for growth before using oxygen from decomposable salts, mainly NH4NO3, under anaerobic condition to produce hydrogen and ethanol. The optimal conditions were determined to be 500 rpm, pH 6.4, 18.5 g/L crude glycerol (15 g/L glycerol and 33% liquid recycling for a fresh feed rate of 0.44 mL/min. Using these optimized conditions, the process ran at a lower media cost than previous studies, was stable after 7 days without further inoculation and resulted in yields of 0.86 mol H2/mol glycerol and 0.75 mol ethanol/mole glycerol.

  18. Biohydrogen and Bioethanol Production from Biodiesel-Based Glycerol by Enterobacter aerogenes in a Continuous Stir Tank Reactor

    Science.gov (United States)

    Jitrwung, Rujira; Yargeau, Viviane

    2015-01-01

    Crude glycerol from the biodiesel manufacturing process is being produced in increasing quantities due to the expanding number of biodiesel plants. It has been previously shown that, in batch mode, semi-anaerobic fermentation of crude glycerol by Enterobacter aerogenes can produce biohydrogen and bioethanol simultaneously. The present study demonstrated the possible scaling-up of this process from small batches performed in small bottles to a 3.6-L continuous stir tank reactor (CSTR). Fresh feed rate, liquid recycling, pH, mixing speed, glycerol concentration, and waste recycling were optimized for biohydrogen and bioethanol production. Results confirmed that E. aerogenes uses small amounts of oxygen under semi-anaerobic conditions for growth before using oxygen from decomposable salts, mainly NH4NO3, under anaerobic condition to produce hydrogen and ethanol. The optimal conditions were determined to be 500 rpm, pH 6.4, 18.5 g/L crude glycerol (15 g/L glycerol) and 33% liquid recycling for a fresh feed rate of 0.44 mL/min. Using these optimized conditions, the process ran at a lower media cost than previous studies, was stable after 7 days without further inoculation and resulted in yields of 0.86 mol H2/mol glycerol and 0.75 mol ethanol/mole glycerol. PMID:25970750

  19. DEVELOPMENT OF A METHANE-FREE, CONTINUOUS BIOHYDROGEN PRODUCTION SYSTEM FROM PALM OIL MILL EFFLUENT (POME IN CSTR

    Directory of Open Access Journals (Sweden)

    MARIATUL FADZILLAH MANSOR

    2016-08-01

    Full Text Available This study aimed to develop the start-up experiment for producing biological hydrogen in 2 L continuous stirred tank reactor (CSTR from palm oil mill effluent (POME by the use of mixed culture sludge under non-sterile conditions. Besides using different source of starter culture, the effects of acid treated culture and various operating temperature from 35 °C to 55 °C were studied against the evolved gas in terms of volumetric H2 production rate (VHPR and soluble metabolite products (SMPs. The formation of methane was closely observed throughout the run. Within the studied temperature, VHPR was found as low as 0.71 L/L.d and ethanol was the main by-products (70-80% of total soluble metabolites. Attempts were made to produce biohydrogen without methane formation at higher thermophilic temperature (45-55 °C than the previous range. The average of 1.7 L H2 of 2 L working volume per day was produced at 55 oC with VHPR of 1.16 L/L.d. The results of soluble metabolites also are in agreement with the volatile fatty acids (VFAs which is higher than ethanol. Higher VFAs of 2269 mg/L was obtained with acetic acid being the main by-product. At this time methanogen has been deactivated and no methane was produced. From this study, it can be concluded that thermophilic environment may offer a better option in a way to eliminate methane from the biogas and at the same time improving hydrogen production rate as well.

  20. Characteristics of biohydrogen production by ethanoligenens R{sub 3} isolated from continuous stirred tank reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jiao, A.Y.; Liu, K. [Northeast Forestry Univ., Harbin (China). School of Forestry; Li, Y.F. [Northeast Forestry Univ., Harbin (China). School of Forestry; Shanghai Univ. of Engineering Science (China). College of Chemistry and Chemical Engineering; Liu, B. [Northeast Forestry Univ., Harbin (China). School of Material Science and Engineering; Xu, J.L. [Shanghai Univ. of Engineering Science (China). College of Chemistry and Chemical Engineering

    2010-07-01

    This study investigated the fermentative hydrogen production characteristics of ethanoligenens R{sub 3} isolated from anaerobic sludge in a continuous stirred tank reactor. The effects of the initial pH value, the proportion of carbon and nitrogen sources, and the effects of fermentation temperature were investigated in a series of batch experiments. Substrates for the hydrogen production of glucose and peptone were used as carbon and nitrogen sources. Results of the experiments showed that a maximum hydrogen production yield of 834 mlH{sub 2}/L culture was obtained with a fermentation temperature of 35 degrees C and an initial pH value of 5.5. The maximum average hydrogen production rate of 10.87 mmolH{sub 2}/g cell dry weight per hour was obtained at a carbon-nitrogen source ratio of 3.3. The degradation efficiency of the glucose used as a carbon source ranged from 91.5 to 95.43 per cent during the conversion of glucose to hydrogen by the bacteria.

  1. Bioelectrochemical Systems for Indirect Biohydrogen Production

    KAUST Repository

    Regan, John M.; Yan, Hengjing

    2014-01-01

    by exoelectrogens at the anode. As an indirect approach to biohydrogen production, these systems are not subject to the hydrogen yield constraints of fermentative processes and have been proven to work with virtually any biodegradable organic substrate

  2. Bioelectrochemical Systems for Indirect Biohydrogen Production

    KAUST Repository

    Regan, John M.

    2014-01-01

    Bioelectrochemical systems involve the use of exoelectrogenic (i.e., anode-reducing) microbes to produce current in conjunction with the oxidation of reduced compounds. This current can be used directly for power in a microbial fuel cell, but there are alternate uses of this current. One such alternative is the production of hydrogen in a microbial electrolysis cell (MEC), which accomplishes cathodic proton reduction with a slight applied potential by exploiting the low redox potential produced by exoelectrogens at the anode. As an indirect approach to biohydrogen production, these systems are not subject to the hydrogen yield constraints of fermentative processes and have been proven to work with virtually any biodegradable organic substrate. With continued advancements in reactor design to reduce the system internal resistance, increase the specific surface area for anode biofilm development, and decrease the material costs, MECs may emerge as a viable alternative technology for biohydrogen production. Moreover, these systems can also incorporate other value-added functionalities for applications in waste treatment, desalination, and bioremediation.

  3. Biohydrogen Production from Glycerol using Thermotoga spp

    NARCIS (Netherlands)

    Maru, B.T.; Bielen, A.A.M.; Kengen, S.W.M.; Constantini, M.; Medina, F.

    2012-01-01

    Given the highly reduced state of carbon in glycerol and its availability as a substantial byproduct of biodiesel production, glycerol is of special interest for sustainable biofuel production. Glycerol was used as a substrate for biohydrogen production using the hyperthermophilic bacterium,

  4. Start up study of UASB reactor treating press mud for biohydrogen production

    International Nuclear Information System (INIS)

    Radjaram, B.; Saravanane, R.

    2011-01-01

    Anaerobic digestion of press mud mixed with water for biohydrogen production was performed in continuous fed UASB bioreactor for 120 days. Experiment was conducted by maintaining constant HRT of 30 h and the volume of biohydrogen evolved daily was monitored. Various parameters like COD, VFA, Alkalinity, EC, Volatile solids, pH with respect to biohydrogen production were monitored at regular interval of time. SBPR was 10.98 ml g -1 COD reduced d -1 and 12.77 ml g -1 VS reduced d -1 on peak yield of biohydrogen. COD reduction was above 70 ± 7%. Maximum gas yield was on the 78th day to 2240 ml d -1 . The aim of the experiment is to study the startup process of UASB reactor for biohydrogen production by anaerobic fermentation of press mud. The inoculum for the process is cow dung and water digested in anaerobic condition for 30 days with municipal sewage sludge. The study explores the viability of biohydrogen production from press mud which is a renewable form of energy to supplement the global energy crisis. -- Highlights: → Feasibility of biohydrogen production from press mud was explored in this study. The gas yield was maximum on the 78th day to 2240 ml d -1 with H 2 % of 52-59%. Biohydrogen yield was about 890 ml kg -1 press mud added d -1 . Press mud is identified as an excellent potential waste to tap energy.

  5. Potential for biohydrogen and methane production from olive pulp

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Skiadas, Ioannis V.; Ahring, Birgitte Kiær

    2005-01-01

    The present study investigates the potential for thermophilic biohydrogen and methane production from olive pulp, which is the semi-solid residue coming from the two-phase processing of olives. It focussed on: a) production of methane from the raw olive pulp, b) anaerobic bio-production of hydrogen...... from the olive pulp, and c) subsequent anaerobic treatment of the hydrogen-effluent with the simultaneous production of methane. Both continuous and batch experiments were performed. The hydrogen potential of the olive pulp amounted to 1.6 mmole H-2 per g TS. The methane potential of the raw olive pulp...... and hydrogen-effluent was as high as 19 mmole CH4 per g TS. This suggests that olive pulp is an ideal substrate for methane production and it shows that biohydrogen production can be very efficiently coupled with a subsequent step for methane production....

  6. Bio-hydrogen Production Potential from Market Waste

    Directory of Open Access Journals (Sweden)

    Lanna Jaitalee

    2010-07-01

    Full Text Available This research studied bio-hydrogen production from vegetable waste from a fresh market in order to recover energy. A series of batch experiments were conducted to investigate the effects of initial volatile solids concentration on the bio-hydrogen production process. Lab bench scale anaerobic continuous stirred-tank reactors (CSTR were used to study the effect of substrate and sludge inoculation on hydrogen production. Three different concentrations of initial total volatile solids (TVS of organic waste were varied from 2%, 3% and 5% respectively. The pH was controlled at 5.5 for all batches in the experiment. The results showed that bio-hydrogen production depended on feed-substrate concentration. At initial TVS content of 3%, the highest hydrogen production was achieved at a level of 0.59 L-H2/L at pH 5.5. The maximum hydrogen yield was 15.3 ml H2/g TVS or 8.5 ml H2/g COD. The composition of H2 in the biogas ranged from 28.1-30.9% and no CH4 was detected in all batch tests.

  7. Evaluation of pretreatment methods on mixed inoculum for both batch and continuous thermophilic biohydrogen production from cassava stillage.

    Science.gov (United States)

    Luo, Gang; Xie, Li; Zou, Zhonghai; Wang, Wen; Zhou, Qi

    2010-02-01

    Anaerobic sludges, pretreated by chloroform, base, acid, heat and loading-shock, as well as untreated sludge were evaluated for their thermophilic fermentative hydrogen-producing characters from cassava stillage in both batch and continuous experiments. Results showed that the highest hydrogen production was obtained by untreated sludge and there were significant differences (pstillage.

  8. Biohydrogen production by anaerobic fermentation of waste. Final project report

    Energy Technology Data Exchange (ETDEWEB)

    Karakashev, D.; Angelidaki, I.

    2009-01-15

    members were phylogenetically affiliated to the genera Bacillus and Clostridium. A thermophilic (60 deg. C) bacterial strain Thermoanaerobacterium thermosaccharolyticum PSU-2 with high yield (2.53 mol H{sub 2}. mol-1 hexose) and production rate of hydrogen 1.12 mmol H{sub 2}.L-l.h-1 was isolated from a biohydrogen reactor fed with palm oil mill effluent. The biofilm of T. thermosaccharolyticum strain PSU-2 developed on heat pretreated methanogenic granules substantially enhanced biomass retention and enhance the hydrogen production. It appeared to be most preferred process configuration for thermophilic continuous hydrogen production from organic wastes. (author)

  9. Biohydrogen production using waste activated sludge disintegrated by gamma irradiation

    International Nuclear Information System (INIS)

    Yin, Yanan; Wang, Jianlong

    2015-01-01

    Highlights: • The waste activated sludge could be disintegrated by gamma irradiation. • The disintegrated sludge could be used for biohydrogen production. • Combined alkali-irradiation treatment achieved the highest solubilization of sludge. - Abstract: The biohydrogen production using the disintegrated and dissolved sludge by gamma irradiation was studied. The experimental results showed that gamma irradiation and irradiation combined with alkali pretreatment could disintegrate and dissolve waste activated sludge for biohydrogen production. The alkali-irradiation treatment of the sludge at pH = 12 and 20 kGy achieved the highest disintegration and dissolution, i.e., it could destroy the cell walls and release organic matters (such as soluble COD, polysaccharides and protein) into the solution. The disintegrated sludge could be used as a low-cost substrate for biohydrogen production

  10. Biohydrogen production as a potential energy fuel in South Africa

    Directory of Open Access Journals (Sweden)

    P.T. Sekoai

    2015-06-01

    Full Text Available Biohydrogen production has captured increasing global attention due to it social, economic and environmental benefits. Over the past few years, energy demands have been growing significantly in South Africa due to rapid economic and population growth. The South African parastatal power supplier i.e. Electricity Supply Commission (ESKOM has been unable to meet the country’s escalating energy needs. As a result, there have been widespread and persistent power cuts throughout the country. This prompts an urgent need for exploration and implementation of clean and sustainable energy fuels like biohydrogen production in order to address this crisis. Therefore, this paper discusses the current global energy challenges in relation to South Africa’s problems. It then examines the feasibility of using biohydrogen production as a potential energy fuel in South Africa. Finally, it reviews the hydrogen-infrastructure development plans in the country.

  11. Biohydrogen production from beet molasses by sequential dark and photofermentation

    NARCIS (Netherlands)

    Özgür, E.; Mars, A.E.; Peksel, B.; Louwerse, A.; Yücel, M.; Gündüz, U.; Claassen, P.A.M.; Eroglu, I.

    2010-01-01

    Biological hydrogen production using renewable resources is a promising possibility to generate hydrogen in a sustainable way. In this study, a sequential dark and photofermentation has been employed for biohydrogen production using sugar beet molasses as a feedstock. An extreme thermophile

  12. Biohydrogen production: prospects and limitations to practical application

    Energy Technology Data Exchange (ETDEWEB)

    Levin, D.B. [Univ. of Victoria, Dept. of Biology and Inst. for Integrated Energy Systems, Victoria, British Columbia (Canada); Pitt, L.; Love, M. [Univ. of Victoria, Inst. for Integrated Energy Systems, Victoria, British Columbia (Canada)

    2003-07-01

    Hydrogen may be produced by a number of processes, including electrolysis of water, thermocatalytic reformation of hydrogen rich organic compounds, and biological processes. Currently, hydrogen is produced, almost exclusively, by electrolysis of water or by steam reformation of methane. Biological production of hydrogen (Biohydrogen) technologies provide a wide range of approaches to generate hydrogen, including Direct biophotolysis, Indirect Biophotolysis, Photo-fermentations, and Dark-fermentation. The practical application of these technologies to every day energy problems, however, is unclear. In order to assess which biohydrogen systems may be practical when combined with fuel cell technologies, we have calculated the size of biohydrogen bioreactors that would be required to power Proton Exchange Membrane (PEM) Fuel Cells of various sizes. Our analysis suggests that light-driven biohydrogen systems (Direct Photolysis, Indirect Photolysis, and Photo-fermentation) do not produce H{sub 2} at rates that are sufficient to power PEMFCs of sufficient size to be of practical use. Thermophilic and extreme thermophilic biohydrogen systems would require very large bioreactors (in the range of approximately 2900 L to 14,600 L) to provide sufficient H{sub 2} to power PEMFCs of 1.5 kW to 5.0 kW, respectively. Some Dark-fermentation systems, however, appear promising. Bioreactors of 500 L and 1000 L, designed so that H{sub 2} is rapidly removed from the culture medium, would be sufficient to power PEMFCs of 2.5 kW and 5.0 kW, respectively. Further research and development aimed at increasing rates of synthesis and final yields of H{sub 2} are essential if biohydrogen systems are to be of practical use. (author)

  13. Biohydrogen production: prospects and limitations to practical application

    International Nuclear Information System (INIS)

    Levin, D.B.; Pitt, L.; Love, M.

    2003-01-01

    Hydrogen may be produced by a number of processes, including electrolysis of water, thermocatalytic reformation of hydrogen rich organic compounds, and biological processes. Currently, hydrogen is produced, almost exclusively, by electrolysis of water or by steam reformation of methane. Biological production of hydrogen (Biohydrogen) technologies provide a wide range of approaches to generate hydrogen, including Direct biophotolysis, Indirect Biophotolysis, Photo-fermentations, and Dark-fermentation. The practical application of these technologies to every day energy problems, however, is unclear. In order to assess which biohydrogen systems may be practical when combined with fuel cell technologies, we have calculated the size of biohydrogen bioreactors that would be required to power Proton Exchange Membrane (PEM) Fuel Cells of various sizes. Our analysis suggests that light-driven biohydrogen systems (Direct Photolysis, Indirect Photolysis, and Photo-fermentation) do not produce H 2 at rates that are sufficient to power PEMFCs of sufficient size to be of practical use. Thermophilic and extreme thermophilic biohydrogen systems would require very large bioreactors (in the range of approximately 2900 L to 14,600 L) to provide sufficient H 2 to power PEMFCs of 1.5 kW to 5.0 kW, respectively. Some Dark-fermentation systems, however, appear promising. Bioreactors of 500 L and 1000 L, designed so that H 2 is rapidly removed from the culture medium, would be sufficient to power PEMFCs of 2.5 kW and 5.0 kW, respectively. Further research and development aimed at increasing rates of synthesis and final yields of H 2 are essential if biohydrogen systems are to be of practical use. (author)

  14. Batch Fermentative Biohydrogen Production Process Using Immobilized Anaerobic Sludge from Organic Solid Waste

    Directory of Open Access Journals (Sweden)

    Patrick T. Sekoai

    2016-12-01

    Full Text Available This study examined the potential of organic solid waste for biohydrogen production using immobilized anaerobic sludge. Biohydrogen was produced under batch mode at process conditions of 7.9, 30.3 °C and 90 h for pH, temperature and fermentation time, respectively. A maximum biohydrogen fraction of 48.67%, which corresponded to a biohydrogen yield of 215.39 mL H2/g Total Volatile Solids (TVS, was achieved. Therefore, the utilization of immobilized cells could pave the way for a large-scale biohydrogen production process.

  15. Sago Biomass as a Sustainable Source for Biohydrogen Production by Clostridium butyricum A1

    Directory of Open Access Journals (Sweden)

    Mohamad Faizal Ibrahim

    2013-12-01

    Full Text Available Biohydrogen production from biomass is attracting many researchers in developing a renewable, clean and environmental friendly biofuel. The biohydrogen producer, Clostridium butyricum A1, was successfully isolated from landfill soil. This strain produced a biohydrogen yield of 1.90 mol H2/mol glucose with productivity of 170 mL/L/h using pure glucose as substrate. The highest cumulative biohydrogen collected after 24 h of fermentation was 2468 mL/L-medium. Biohydrogen fermentation using sago hampas hydrolysate produced higher biohydrogen yield (2.65 mol H2/mol glucose than sago pith residue (SPR hydrolysate that produced 2.23 mol H2/mol glucose. A higher biohydrogen productivity of 1757 mL/L/h was obtained when using sago hampas hydrolysate compared to when using pure glucose that has the productivity of 170 mL/L/h. A comparable biohydrogen production was also obtained by C. butyricum A1 when compared to C. butyricum EB6 that produced a biohydrogen yield of 2.50 mol H2/mol glucose using sago hampas hydrolysate as substrate. This study shows that the new isolate C. butyricum A1 together with the use of sago biomass as substrate is a promising technology for future biohydrogen production.

  16. Biohydrogen production from organic waste and wastewater by dark fermentation. A promising module for renewable energy production

    Energy Technology Data Exchange (ETDEWEB)

    Krupp, M.

    2007-07-01

    Fossil fuels are limited and global warming due to increased CO{sub 2}-emissions may lead to worldwide environmental disasters. Therefore energy production from renewable sources is the most important task in the future. In the contribution under consideration, the author reports on biohydrogen production from organic waste and wastewater by dark fermentation.An engineered approach was chosen to get more information about the technical feasibility of a process which has been studied intensively in the current century. The developed test method represents a functional tool for determination of the biohydrogen production potential of a wide variety of different substances. The implementation of the 'glucose equivalent' for estimation of the biohydrogen potential of a certain substrate was a successfull approach. With this parameter, the biohydrogen potential could be evaluated properly without severe influence from the boundary conditions. Within the continuous test trials it could be found that continuous biohydrogen production in a 30 L-scale is feasible without costly regulation and control mechanisms. The further test series conducted in 30 L-scale gave important results for pilot plant design. One main result of the test runs is that it was shown that the control mechanisms could be reduced to a simple pH-regulation by addition of sodium hydroxide. Other parameters like organic loading rate (OLR) and hydraulic retention time (HRT) were clearly more important to ensure a stable continuous process. A HRT of 15-20 hours combined with an OLR of up to 14 kg VS/(d m{sup 3}) resulted in very high hydrogen yields of 2.14-2.56 mol H{sub 2}/mol glucose. Another important result for pilot plant construction was the necessity of input cooling. Due to ambient temperatures in the input vessels the substrate tests failed. Hydrolysis took place in the input vessels, not in the reactors. Gas upgrading by membrane systems was tested as well as post-methanisation or

  17. Biohydrogen production from soluble condensed molasses fermentation using anaerobic fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Lay, Chyi-How; Lin, Chiu-Yue [Department of Environmental Engineering and Science, Feng Chia University, Taichung 40724 (China); Wu, Jou-Hsien; Hsiao, Chin-Lang [Department of Water Resource Engineering, Feng Chia University (China); Chang, Jui-Jen [Department of Life Sciences, National Chung Hsing University (China); Chen, Chin-Chao [Environmental Resources Laboratory, Department of Landscape Architecture, Chungchou Institute of Technology (China)

    2010-12-15

    Using anaerobic micro-organisms to convert organic waste to produce hydrogen gas gives the benefits of energy recovery and environmental protection. The objective of this study was to develop a biohydrogen production technology from food wastewater focusing on hydrogen production efficiency and micro-flora community at different hydraulic retention times. Soluble condensed molasses fermentation (CMS) was used as the substrate because it is sacchariferous and ideal for hydrogen production. CMS contains nutrient components that are necessary for bacterial growth: microbial protein, amino acids, organic acids, vitamins and coenzymes. The seed sludge was obtained from the waste activated sludge from a municipal sewage treatment plant in Central Taiwan. This seed sludge was rich in Clostridium sp. A CSTR (continuously stirred tank reactor) lab-scale hydrogen fermentor (working volume, 4.0 L) was operated at a hydraulic retention time (HRT) of 3-24 h with an influent CMS concentration of 40 g COD/L. The results showed that the peak hydrogen production rate of 390 mmol H{sub 2}/L-d occurred at an organic loading rate (OLR) of 320 g COD/L-d at a HRT of 3 h. The peak hydrogen yield was obtained at an OLR of 80 g COD/L-d at a HRT of 12 h. At HRT 8 h, all hydrogenase mRNA detected were from Clostridium acetobutylicum-like and Clostridium pasteurianum-like hydrogen-producing bacteria by RT-PCR analysis. RNA based hydrogenase gene and 16S rRNA gene analysis suggests that Clostridium exists in the fermentative hydrogen-producing system and might be the dominant hydrogen-producing bacteria at tested HRTs (except 3 h). The hydrogen production feedstock from CMS is lower than that of sucrose and starch because CMS is a waste and has zero cost, requiring no added nutrients. Therefore, producing hydrogen from food wastewater is a more commercially feasible bioprocess. (author)

  18. Enhancement of Biohydrogen Production via pH Variation using Molasses as Feedstock in an Attached Growth System

    Directory of Open Access Journals (Sweden)

    Che Zuhar C.N.S.

    2018-01-01

    Full Text Available In this study, mesophilic biohydrogen production by a mixed culture, obtained from a continuous anaerobic reactor treating molasses effluent from sugarcane bagasse, was improved by using granular activated carbon (GAC as the carrier material. A series of batch fermentation were performed at 37°C by feeding the anaerobic sludge bacteria with molasses to determine the effect of initial pH in the range of 5.5 to 7.5, and the effect of repeated batch cultivation on biohydrogen production. The enrichment of granular activated carbon (GAC immobilised cells from the repeated batch cultivation were used as immobilised seed culture to obtain the optimal initial pH. The cumulative hydrogen production results from the optimal pH were fitted into modified Gompertz equation in order to obtained the batch profile of biohydrogen production. The optimal hydrogen production was obtained at an initial pH of 5.5 with the maximum hydrogen production (Hm was found to be 84.14 ml, and maximum hydrogen production rate (Rm was 3.63 mL/h with hydrogen concentration of 759 ppm. The results showed that the granular activated carbon was successfully enhanced the biohydrogen production by stabilizing the pH and therefore could be used as a carrier material for fermentative hydrogen production using industrial effluent.

  19. Enhancement of Biohydrogen Production via pH Variation using Molasses as Feedstock in an Attached Growth System

    Science.gov (United States)

    Che Zuhar, C. N. S.; Lutpi, N. A.; Idris, N.; Wong, Y. S.; Tengku Izhar, T. N.

    2018-03-01

    In this study, mesophilic biohydrogen production by a mixed culture, obtained from a continuous anaerobic reactor treating molasses effluent from sugarcane bagasse, was improved by using granular activated carbon (GAC) as the carrier material. A series of batch fermentation were performed at 37°C by feeding the anaerobic sludge bacteria with molasses to determine the effect of initial pH in the range of 5.5 to 7.5, and the effect of repeated batch cultivation on biohydrogen production. The enrichment of granular activated carbon (GAC) immobilised cells from the repeated batch cultivation were used as immobilised seed culture to obtain the optimal initial pH. The cumulative hydrogen production results from the optimal pH were fitted into modified Gompertz equation in order to obtained the batch profile of biohydrogen production. The optimal hydrogen production was obtained at an initial pH of 5.5 with the maximum hydrogen production (Hm) was found to be 84.14 ml, and maximum hydrogen production rate (Rm) was 3.63 mL/h with hydrogen concentration of 759 ppm. The results showed that the granular activated carbon was successfully enhanced the biohydrogen production by stabilizing the pH and therefore could be used as a carrier material for fermentative hydrogen production using industrial effluent.

  20. Bio-hydrogen production from hyacinth by anaerobic fermentation

    International Nuclear Information System (INIS)

    Cheng Jun; Zhou Junhu; Qi Feng; Xie Binfei; Cen Kefa

    2006-01-01

    The bio-hydrogen production from hyacinth by anaerobic fermentation of digested sludge is studied in this paper. The compositions of bio-gases and volatile fatty acids in fermentation liquids are determined on TRACE 2000 gas chromatography. It is found that the H 2 concentration in the biogas is 10%-20% and no CH 4 is detected. The bio-hydrogen production from hyacinth with the initial pH value of 5.5 is higher than that with the initial pH value of 4.5. The fermentation temperature of 55 C is better than that of 35 C, while the weight ratio of hyacinth to microorganism of 1:1 is better than that of 3:7. The highest hydrogen production of 122.3 mL/g is obtained when the initial pH value of fermentation solution is 5.5, the fermentation temperature is 55 C and the weight ratio of hyacinth to microorganism is 1:1. (authors)

  1. Improvement of anaerobic bio-hydrogen gas production from organic sludge waste

    International Nuclear Information System (INIS)

    Lee, S.; Lee, Y. H.

    2009-01-01

    Microbial hydrogen gas production from organic matters stands out as one of the most promising alternatives for sustainable green energy production. Based on the literature review, investigation of anaerobic bio-hydrogen gas production from organic sludge waste using a mixed culture has been very limited. The objective of this study was to assess the anaerobic bio-hydrogen gas production from organic sludge waste under various conditions. (Author)

  2. Biohydrogen production from specified risk materials co-digested with cattle manure

    Energy Technology Data Exchange (ETDEWEB)

    Gilroyed, Brandon H. [Agriculture and Agri-Food Canada, Lethbridge Research Centre, P.O. Box 3000, Lethbridge, Alberta T1J 4B1 (Canada); Department of Civil Engineering, Schulich School of Engineering, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Li, Chunli; Hao, Xiying; McAllister, Tim A. [Agriculture and Agri-Food Canada, Lethbridge Research Centre, P.O. Box 3000, Lethbridge, Alberta T1J 4B1 (Canada); Chu, Angus [Department of Civil Engineering, Schulich School of Engineering, University of Calgary, Calgary, Alberta T2N 1N4 (Canada)

    2010-02-15

    Biohydrogen production from the anaerobic digestion of specified risk materials (SRM) co-digested with cattle manure was assessed in a 3 x 5 factorial design. Total organic loading rates (OLR) of 10, 20, and 40 g L{sup -1} volatile solids (VS) were tested using manure:SRM (wt/wt) mixtures of 100:0 (control), 90:10, 80:20, 60:40, and 50:50 using five 2 L continuously stirred biodigesters operating at 55 C. Gas samples were taken daily to determine hydrogen production, and slurry samples were analyzed daily for volatile fatty acid (VFA) concentration, total ammonia nitrogen (TAN), and VS degradation. Hydrogen production (mL g{sup -1} VS fed) varied quadratically according to OLR (P < 0.01), with maximum production at OLR20, while production decreased linearly (P < 0.0001) as SRM concentration increased. Reduced hydrogen production associated with SRM inclusion at >10% VS may be attributed to a rapid increase in TAN (r = -0.55) or other inhibitors such as long chain fatty acids. Reduced hydrogen production (P < 0.01) at OLR40 versus OLR20 may be related to increased rate of VFA accumulation and final VFA concentration (P < 0.001), as well as inhibition due to hydrogen accumulation (P < 0.001). Biohydrogen production from SRM co-digested with cattle manure may not be feasible on an industrial scale due to reduced hydrogen production with increasing levels of SRM. (author)

  3. Appraisal of bio-hydrogen production schemes

    International Nuclear Information System (INIS)

    Bent Sorensen

    2006-01-01

    Work is ongoing on several schemes of biological hydrogen production. At one end is the genetic modification of biological systems (such as algae or cyanobacteria) to produce hydrogen from photosynthesis, instead of the energy-rich compounds (such as NADPH 2 ) normally constituting the endpoint of the transformations through the photo-systems. A second route is to collect and use the biomass produced by normal plant growth processes in a separate step that produces hydrogen. This may be done similar to biogas production by fermentation, where the endpoint is methane (plus CO 2 and minor constituents). Hydrogen could be the outcome of a secondary process starting from methane, involving any of the conventional methods of hydrogen production from natural gas. An alternative to fermentation is gasification of the biomass, followed by a shift-reaction leading to hydrogen. I compare advantages and disadvantages of these three routes, notably factors such as system efficiency, cost and environmental impacts, and also compare them to liquid biofuels. (author)

  4. 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.

  5. The organic agricultural waste as a basic source of biohydrogen production

    Science.gov (United States)

    Sriwuryandari, Lies; Priantoro, E. Agung; Sintawardani, Neni; Astuti, J. Tri; Nilawati, Dewi; Putri, A. Mauliva Hada; Mamat, Sentana, Suharwadji; Sembiring, T.

    2016-02-01

    Biohydrogen production research was carried out using raw materials of agricultural organic waste that was obtained from markets around the Bandung city. The organic part, which consisted of agricultural waste material, mainly fruit and vegetable waste, was crushed and milled using blender. The sludge that produced from milling process was then used as a substrate for mixed culture microorganism as a raw material to produce biohydrogen. As much as 1.2 kg.day-1 of sludge (4% of total solid) was fed into bioreactor that had a capacity of 30L. Experiment was done under anaerobic fermentation using bacteria mixture culture that maintained at pH in the range of 5.6-6.5 and temperature of 25-30oC on semi-continuous mode. Parameters of analysis include pH, temperature, total solid (TS), organic total solid (OTS), total gas production, and hydrogen gas production. The results showed that from 4% of substrate resulted 897.86 L of total gas, which contained 660.74 L (73.59%) of hydrogen gas. The rate of hydrogen production in this study was 11,063 mol.L-1.h-1.

  6. Bio-hydrogen production from renewable organic wastes

    Energy Technology Data Exchange (ETDEWEB)

    Shihwu Sung

    2004-04-30

    Methane fermentation has been in practice over a century for the stabilization of high strength organic waste/wastewater. Although methanogenesis is a well established process and methane--the end-product of methanogenesis is a useful energy source; it is a low value end product with relatively less energy content (about 56 kJ energy/g CH{sub 4}). Besides, methane and its combustion by-product are powerful greenhouse gases, and responsible for global climate change. So there is a pressing need to explore alternative environmental technologies that not only stabilize the waste/wastewater but also generate benign high value end products. From this perspective, anaerobic bioconversion of organic wastes to hydrogen gas is an attractive option that achieves both goals. From energy security stand point, generation of hydrogen energy from renewable organic waste/wastewater could substitute non-renewable fossil fuels, over two-third of which is imported from politically unstable countries. Thus, biological hydrogen production from renewable organic waste through dark fermentation represents a critically important area of bioenergy production. This study evaluated both process engineering and microbial physiology of biohydrogen production.

  7. A comprehensive and quantitative review of dark fermentative biohydrogen production

    Directory of Open Access Journals (Sweden)

    Rittmann Simon

    2012-08-01

    Full Text Available Abstract Biohydrogen production (BHP can be achieved by direct or indirect biophotolysis, photo-fermentation and dark fermentation, whereof only the latter does not require the input of light energy. Our motivation to compile this review was to quantify and comprehensively report strains and process performance of dark fermentative BHP. This review summarizes the work done on pure and defined co-culture dark fermentative BHP since the year 1901. Qualitative growth characteristics and quantitative normalized results of H2 production for more than 2000 conditions are presented in a normalized and therefore comparable format to the scientific community. Statistically based evidence shows that thermophilic strains comprise high substrate conversion efficiency, but mesophilic strains achieve high volumetric productivity. Moreover, microbes of Thermoanaerobacterales (Family III have to be preferred when aiming to achieve high substrate conversion efficiency in comparison to the families Clostridiaceae and Enterobacteriaceae. The limited number of results available on dark fermentative BHP from fed-batch cultivations indicates the yet underestimated potential of this bioprocessing application. A Design of Experiments strategy should be preferred for efficient bioprocess development and optimization of BHP aiming at improving medium, cultivation conditions and revealing inhibitory effects. This will enable comparing and optimizing strains and processes independent of initial conditions and scale.

  8. Scale-up and optimization of biohydrogen production reactor from laboratory-scale to industrial-scale on the basis of computational fluid dynamics simulation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xu; Ding, Jie; Guo, Wan-Qian; Ren, Nan-Qi [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 202 Haihe Road, Nangang District, Harbin, Heilongjiang 150090 (China)

    2010-10-15

    The objective of conducting experiments in a laboratory is to gain data that helps in designing and operating large-scale biological processes. However, the scale-up and design of industrial-scale biohydrogen production reactors is still uncertain. In this paper, an established and proven Eulerian-Eulerian computational fluid dynamics (CFD) model was employed to perform hydrodynamics assessments of an industrial-scale continuous stirred-tank reactor (CSTR) for biohydrogen production. The merits of the laboratory-scale CSTR and industrial-scale CSTR were compared and analyzed on the basis of CFD simulation. The outcomes demonstrated that there are many parameters that need to be optimized in the industrial-scale reactor, such as the velocity field and stagnation zone. According to the results of hydrodynamics evaluation, the structure of industrial-scale CSTR was optimized and the results are positive in terms of advancing the industrialization of biohydrogen production. (author)

  9. Food waste and food processing waste for biohydrogen production: a review.

    Science.gov (United States)

    Yasin, Nazlina Haiza Mohd; Mumtaz, Tabassum; Hassan, Mohd Ali; Abd Rahman, Nor'Aini

    2013-11-30

    Food waste and food processing wastes which are abundant in nature and rich in carbon content can be attractive renewable substrates for sustainable biohydrogen production due to wide economic prospects in industries. Many studies utilizing common food wastes such as dining hall or restaurant waste and wastes generated from food processing industries have shown good percentages of hydrogen in gas composition, production yield and rate. The carbon composition in food waste also plays a crucial role in determining high biohydrogen yield. Physicochemical factors such as pre-treatment to seed culture, pH, temperature (mesophilic/thermophilic) and etc. are also important to ensure the dominance of hydrogen-producing bacteria in dark fermentation. This review demonstrates the potential of food waste and food processing waste for biohydrogen production and provides a brief overview of several physicochemical factors that affect biohydrogen production in dark fermentation. The economic viability of biohydrogen production from food waste is also discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Novel fungal consortium pretreatment of waste oat straw to enhance economic and efficient biohydrogen production

    Directory of Open Access Journals (Sweden)

    Lirong Zhou

    2016-12-01

    Full Text Available Bio-pretreatment using a fungal consortium to enhance the efficiency of lignocellulosic biohydrogen production was explored.  A fungal consortium comprised of T. viride and P. chrysosporium as microbial inoculum was compared with untreated and single-species-inoculated samples. Fungal bio-pretreatment was carried out at atmospheric conditions with limited external energy input.  The effectiveness of the pretreatment is evaluated according to its lignin removal and digestibility. Enhancement of biohydrogen production is observed through scanning electron microscopy (SEM analysis. Fungal consortium pretreatment effectively degraded oat straw lignin (by >47% in 7 days leading to decomposition of cell-wall structure as revealed in SEM images, increasing biohydrogen yield. The hydrogen produced from the fungal consortium pretreated straw increased by 165% 6 days later, and was more than produced from either a single fungi species of T. viride or P. chrysosponium pretreated straw (94% and 106%, respectively. No inhibitory effect on hydrogen production was observed.

  11. Comparing the Bio-Hydrogen Production Potential of Pretreated Rice Straw Co-Digested with Seeded Sludge Using an Anaerobic Bioreactor under Mesophilic Thermophilic Conditions

    Directory of Open Access Journals (Sweden)

    Asma Sattar

    2016-03-01

    Full Text Available Three common pretreatments (mechanical, steam explosion and chemical used to enhance the biodegradability of rice straw were compared on the basis of bio-hydrogen production potential while co-digesting rice straw with sludge under mesophilic (37 °C and thermophilic (55 °C temperatures. The results showed that the solid state NaOH pretreatment returned the highest experimental reduction of LCH (lignin, cellulose and hemi-cellulose content and bio-hydrogen production from rice straw. The increase in incubation temperature from 37 °C to 55 °C increased the bio-hydrogen yield, and the highest experimental yield of 60.6 mL/g VSremoved was obtained under chemical pretreatment at 55 °C. The time required for maximum bio-hydrogen production was found on the basis of kinetic parameters as 36 h–47 h of incubation, which can be used as a hydraulic retention time for continuous bio-hydrogen production from rice straw. The optimum pH range of bio-hydrogen production was observed to be 6.7 ± 0.1–5.8 ± 0.1 and 7.1 ± 0.1–5.8 ± 0.1 under mesophilic and thermophilic conditions, respectively. The increase in temperature was found useful for controlling the volatile fatty acids (VFA under mechanical and steam explosion pretreatments. The comparison of pretreatment methods under the same set of experimental conditions in the present study provided a baseline for future research in order to select an appropriate pretreatment method.

  12. Optimizing the impact of temperature on bio-hydrogen production from food waste and its derivatives under no pH control using statistical modelling

    Science.gov (United States)

    Arslan, C.; Sattar, A.; Ji, C.; Sattar, S.; Yousaf, K.; Hashim, S.

    2015-11-01

    The effect of temperature on bio-hydrogen production by co-digestion of sewerage sludge with food waste and its two derivatives, i.e. noodle waste and rice waste, was investigated by statistical modelling. Experimental results showed that increasing temperature from mesophilic (37 °C) to thermophilic (55 °C) was an effective mean for increasing bio-hydrogen production from food waste and noodle waste, but it caused a negative impact on bio-hydrogen production from rice waste. The maximum cumulative bio-hydrogen production of 650 mL was obtained from noodle waste under thermophilic temperature condition. Most of the production was observed during the first 48 h of incubation, which continued until 72 h of incubation. The decline in pH during this interval was 4.3 and 4.4 from a starting value of 7 under mesophilic and thermophilic conditions, respectively. Most of the glucose consumption was also observed during 72 h of incubation and the maximum consumption was observed during the first 24 h, which was the same duration where the maximum pH drop occurred. The maximum hydrogen yields of 82.47 mL VS-1, 131.38 mL COD-1, and 44.90 mL glucose-1 were obtained from thermophilic food waste, thermophilic noodle waste and mesophilic rice waste, respectively. The production of volatile fatty acids increased with an increase in time and temperature in food waste and noodle waste reactors whereas they decreased with temperature in rice waste reactors. The statistical modelling returned good results with high values of coefficient of determination (R2) for each waste type and 3-D response surface plots developed by using models developed. These plots developed a better understanding regarding the impact of temperature and incubation time on bio-hydrogen production trend, glucose consumption during incubation and volatile fatty acids production.

  13. Biohydrogen Production from Pineapple Waste: Effect of Substrate Concentration and Acid Pretreatment

    Science.gov (United States)

    Cahyari, K.; Putri, A. M.; Oktaviani, E. D.; Hidayat, M. A.; Norajsha, J. D.

    2018-05-01

    Biohydrogen is the ultimate choice of energy carrier in future due to its superior qualities such as fewer greenhouse gases emission, high energy density (142 kJ/gram), and high energy conversion using a fuel cell. Production of biohydrogen from organic waste e.g. pineapple waste offers a simultaneous solution for renewable energy production and waste management. It is estimated that pineapple cultivation in Indonesia generated more than 1 million ton/year comprising of rotten pineapple fruit, leaves, and stems. Majority of this waste is dumped into landfill area without any treatments which lead to many environmental problems. This research was meant to investigate the utilization of pineapple waste i.e. peel and the core of pineapple fruit and leaves to produce biohydrogen through mesophilic dark fermentation (30°C, 1 atm, pH 5.0). Effect of dilute acid treatment and substrate concentration was particularly investigated in these experiments. Peel and core of pineapple waste were subjected to fermentation at 3 various substrate concentration i.e. 8.8, 17.6 and 26.4-gram VS/liter. Meanwhile, pineapple leaves were pretreated using dilute acid (H2SO4) at 0.2, 0.3 and 0.4 N and followed by dark fermentation. Results show that the highest yield of biohydrogen was obtained at a substrate concentration of 26.4-gram VS/liter both for peel and core of the waste. Pretreatment using dilute acid (H2SO4) 0.3 N might improve fermentation process with a higher yield at 0.8 ml/gram VS. Hydrogen percentage in biogas produced during fermentation process was in the range between 5 – 32% of volume ratio. In summary, it is possible to utilize pineapple waste for production of biohydrogen at an optimum substrate concentration of 26.4-gram VS/liter and acid pretreatment (H2SO4) of 0.3 N.

  14. Biohydrogen production in the suspended and attached microbial growth systems from waste pastry hydrolysate.

    Science.gov (United States)

    Han, Wei; Hu, Yunyi; Li, Shiyi; Li, Feifei; Tang, Junhong

    2016-10-01

    Waste pastry was hydrolyzed by glucoamylase and protease which were obtained from solid state fermentation of Aspergillus awamori and Aspergillus oryzae to produce waste pastry hydrolysate. Then, the effects of hydraulic retention times (HRTs) (4-12h) on hydrogen production rate (HPR) in the suspended microbial growth system (continuous stirred tank reactor, CSTR) and attached microbial growth system (continuous mixed immobilized sludge reactor, CMISR) from waste pastry hydrolysate were investigated. The maximum HPRs of CSTR (201.8mL/(h·L)) and CMISR (255.3mL/(h·L)) were obtained at HRT of 6h and 4h, respectively. The first-order reaction could be used to describe the enzymatic hydrolysis of waste pastry. The carbon content of the waste pastry remained 22.8% in the undigested waste pastry and consumed 77.2% for carbon dioxide and soluble microbial products. To our knowledge, this is the first study which reports biohydrogen production from waste pastry. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. 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).

  16. Biohydrogen production from a novel alkalophilic isolate Clostridium sp. IODB-O3.

    Science.gov (United States)

    Patel, Anil Kumar; Debroy, Arundhati; Sharma, Sandeep; Saini, Reetu; Mathur, Anshu; Gupta, Ravi; Tuli, Deepak Kumar

    2015-01-01

    Hydrogen producing bacteria IODB-O3 was isolated from sludge and identified as Clostridium sp. by 16S rDNA gene analysis. In this study, biohydrogen production process was developed using low-cost agro-waste. Maximum H2 was produced at 37°C and pH 8.5. Maximum H2 yield was obtained 2.54±0.2mol-H2/mol-reducing sugar from wheat straw pre-hydrolysate (WSPH) and 2.61±0.1mol-H2/mol-reducing sugar from pre-treated wheat straw enzymatic-hydrolysate (WSEH). The cumulative H2 production (ml/L), 3680±105 and 3270±100, H2 production rate (ml/L/h), 153±5 and 136±5, and specific H2 production (ml/g/h), 511±5 and 681±10 with WSPH and WSEH were obtained, respectively. Biomass pre-treatment via steam-explosion generates ample amount of WSPH which remains unutilized for bioethanol production due to non-availability of efficient C5-fermenting microorganisms. This study shows that Clostridium sp. IODB-O3 is capable of utilizing WSPH efficiently for biohydrogen production. This would lead to reduced economic constrain on the overall cellulosic ethanol process and also establish a sustainable biohydrogen production process. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Enzymatic saccharification and fermentation of paper and pulp industry effluent for biohydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Lakshmidevi, Rajendran; Muthukumar, Karuppan [Department of Chemical Engineering, Alagappa College of Technology Campus, Anna University Chennai, Chennai 600 025 (India)

    2010-04-15

    Paper and pulp industry effluent was enzymatically hydrolysed using crude cellulase enzyme (0.8-2.2FPU/ml) obtained from Trichoderma reesei and from the hydrolysate biohydrogen was produced using Enterobacter aerogenes. The influence of temperature and incubation time on enzyme production was studied. The optimum temperature for the growth of T. reesei was found to be around 29 C. The enzyme activity of 2.5 FPU/ml was found to produce about 22 g/l of total sugars consisting mainly of glucose, xylose and arabinose. Relevant kinetic parameters with respect to sugars production were estimated using two fraction model. The enzymatic hydrolysate was used for the biohydrogen production using E. aerogenes. The growth data obtained for E. aerogenes were fitted well with Monod and Logistic equations. The maximum hydrogen yield of 2.03 mol H{sub 2}/mol sugar and specific hydrogen production rate of 225 mmol of H{sub 2}/g cell/h were obtained with an initial concentration of 22 g/l of total sugars. The colour and COD of effluent was also decreased significantly during the production of hydrogen. The results showed that the paper and pulp industry effluent can be used as a substrate for biohydrogen production. (author)

  18. Biohydrogen production and wastewater treatment from organic wastewater by anaerobic fermentation with UASB

    Science.gov (United States)

    Wang, Lu; Li, Yong-feng; Wang, Yi-xuan; Yang, Chuan-ping

    2010-11-01

    In order to discuss the ability of H2-production and wastewater treatment, an up-flow anaerobic sludge bed (UASB) using a synthesized substrate with brown sugar wastewater was conducted to investigate the hydrogen yield, hydrogen producing rate, fermentation type of biohydrogen production, and the chemical oxygen demand (COD) removal rate, respectively. The results show that when the biomass of inoculants was 22.5 g SSṡL-1 and the influent concentration, hydraulic retention time (HRT) and initial pH were within the ranges of 4000˜6000 mg CODṡL-1, 8 h and 5-5.5, respectively, and the biohydrogen producing reactor could work effectively. The maximum hydrogen production rate is 5.98 Lṡd-1. Simultaneously, the concentration of ethanol and acetic acid is around 80% of the aqueous terminal production in the system, which presents the typical ethanol type fermentation. pH is at the range of 4˜4.5 during the whole performing process, however, the removal rate of COD is just about 20%. Therefore, it's still needs further research to successfully achieve the biohydrogen production and wastewater treatment, simultaneously.

  19. Production and storage of biohydrogen during sequential batch fermentation of Spirogyra hydrolyzate by Clostridium butyricum

    International Nuclear Information System (INIS)

    Ortigueira, Joana; Pinto, Tiago; Gouveia, Luísa; Moura, Patrícia

    2015-01-01

    The biological hydrogen production from Spirogyra sp. biomass was studied in a SBR (sequential batch reactor) equipped with a biogas collecting and storage system. Two acid hydrolysis pre-treatments (1N and 2N H 2 SO 4 ) were applied to the Spirogyra biomass and the subsequent fermentation by Clostridium butyricum DSM 10702 was compared. The 1N and 2N hydrolyzates contained 37.2 and 40.8 g/L of total sugars, respectively, and small amounts of furfural and HMF (hydroxymethylfurfural). These compounds did not inhibit the hydrogen production from crude Spirogyra hydrolyzates. The fermentation was scaled up to a batch operated bioreactor coupled with a collecting system that enabled the subsequent characterization and storage of the biogas produced. The cumulative hydrogen production was similar for both 1N and 2N hydrolyzate, but the hydrogen production rates were 438 and 288 mL/L.h, respectively, suggesting that the 1N hydrolyzate was more suitable for sequential batch fermentation. The SBR with 1N hydrolyzate was operated continuously for 13.5 h in three consecutive batches and the overall hydrogen production rate and yield reached 324 mL/L.h and 2.59 mol/mol, respectively. This corresponds to a potential daily production of 10.4 L H 2 /L Spirogyra hydrolyzate, demonstrating the excellent capability of C. butyricum to produce hydrogen from microalgal biomass. - Highlights: • Production of biohydrogen from crude Spirogyra hydrolyzates. • Set-up of a collecting and storage system for continuous biogas sampling. • The hydrogen production rate is 324 mL/L.h in the SBR (sequential batch reactor). • The SBR produces daily an equivalent to 10.4 L H 2 /L of crude Spirogyra hydrolyzate

  20. Optimizing the impact of temperature on bio-hydrogen production from food waste and its derivatives under no pH control using statistical modelling

    OpenAIRE

    A. Sattar; C. Arslan; C. Ji; S. Sattar; K. Yousaf; S. Hashim

    2015-01-01

    The effect of temperature on bio-hydrogen production by co-digestion of sewerage sludge with food waste and its two derivatives, i.e. noodle waste and rice waste, was investigated by statistical modelling. Experimental results showed that increasing temperature from mesophilic (37 °C) to thermophilic (55 °C) was an effective mean for increasing bio-hydrogen production from food waste and noodle waste, but it caused a negative impact on bio-hydrogen productio...

  1. Comparative techno-economic analysis of biohydrogen production via bio-oil gasification and bio-oil reforming

    International Nuclear Information System (INIS)

    Zhang, Yanan; Brown, Tristan R.; Hu, Guiping; Brown, Robert C.

    2013-01-01

    This paper evaluates the economic feasibility of biohydrogen production via two bio-oil processing pathways: bio-oil gasification and bio-oil reforming. Both pathways employ fast pyrolysis to produce bio-oil from biomass stock. The two pathways are modeled using Aspen Plus ® for a 2000 t d −1 facility. Equipment sizing and cost calculations are based on Aspen Economic Evaluation® software. Biohydrogen production capacity at the facility is 147 t d −1 for the bio-oil gasification pathway and 160 t d −1 for the bio-oil reforming pathway. The biomass-to-fuel energy efficiencies are 47% and 84% for the bio-oil gasification and bio-oil reforming pathways, respectively. Total capital investment (TCI) is 435 million dollars for the bio-oil gasification pathway and is 333 million dollars for the bio-oil reforming pathway. Internal rates of return (IRR) are 8.4% and 18.6% for facilities employing the bio-oil gasification and bio-oil reforming pathways, respectively. Sensitivity analysis demonstrates that biohydrogen price, biohydrogen yield, fixed capital investment (FCI), bio-oil yield, and biomass cost have the greatest impacts on facility IRR. Monte-Carlo analysis shows that bio-oil reforming is more economically attractive than bio-oil gasification for biohydrogen production. -- Highlights: ► Biohydrogen production via bio-oil reforming has higher energy efficiency compared to gasification. ► Hydrogen price, fixed capital cost, and feedstock cost most strongly affect IRR. ► Lower risk investment is biohydrogen production via bio-oil reforming

  2. Dual uses of microalgal biomass: An integrative approach for biohydrogen and biodiesel production

    International Nuclear Information System (INIS)

    Dasgupta, Chitralekha Nag; Suseela, M.R.; Mandotra, S.K.; Kumar, Pankaj; Pandey, Manish K.; Toppo, Kiran; Lone, J.A.

    2015-01-01

    Highlights: • Chlorella sp. NBRI029 and Scenedesmus sp. NBRI012 shows high biomass productivity. • Scenedesmus sp. NBRI012 shows maximum H 2 evolution in 6th day of fermentation. • Residual biomass after H 2 production contains high lipid content. • Lipid extracted from the residual biomass fulfills various biodiesel properties. - Abstract: Dual application of biomass for biohydrogen and biodiesel production could be considered a feasible option for economic and sustainable energy production from microalgae. In this study, after a large screening of fresh water microalgal isolates, Scenedesmus sp. NBRI012 and Chlorella sp. NBRI029 have exhibited high biomass (1.31 ± 0.11 and 2.62 ± 0.13 g/L respectively) and lipid (244.44 ± 12.3 and 587.38 ± 20.2 mg/L respectively) yield with an organic carbon (acetate) source. Scenedesmus sp. NBRI012 has shown the highest H 2 (maximum evolution of 17.72% v/v H 2 of total gases) production; it produced H 2 continuously for seven days in sulfur-deprived TAP media. Sulfur deprivation during the H 2 production was found to increase the lipid content (410.03 ± 18.5 mg/L) of the residual biomass. Fatty acid profile of the lipid extracted from the residual biomass of Scenedesmus sp. NBRI012 has showed abundance of fatty acids with a carbon chain length of C16 and C18. Cetane number, iodine value, and saponification value of biodiesel were found suitable according to the range given by the Indian standard (IS 15607), Brazilian National Petroleum Agency (ANP255) and the European biodiesel standard EN14214

  3. Improving photofermentative biohydrogen production by using intermittent ultrasonication and combined industrial effluents from palm oil, pulp and paper mills

    International Nuclear Information System (INIS)

    Budiman, Pretty Mori; Wu, Ta Yeong; Ramanan, Ramakrishnan Nagasundara; Md Jahim, Jamaliah

    2017-01-01

    Highlights: • Intermittent ultrasonication onto broth improved biohydrogen production. • A20T10 treatment produced 14.438 mL H_2/mL_m_e_d_i_u_m with 7.412% light efficiency. • Excessive ultrasonication (>306.1 J/mL) inhibited biohydrogen production. - Abstract: An ultrasonication technique was applied intermittently onto photofermentation broth during the first six hours of photofermentation to improve biohydrogen production by using Rhodobacter sphaeroides NCIMB8253. In this research, photofermentation broth consisted of a combination of palm oil (25%, v/v), pulp and paper (75%, v/v) mill effluents as well as liquid inoculum. The effects of amplitude (10, 20 and 30%, A) and ultrasonication duration (5, 10 and 15 min, T) were investigated in terms of their influences on photofermentative biohydrogen yield and total chemical oxygen demand (COD_t_o_t_a_l) removal. The recommended ultrasonication parameters were found at the middle range of amplitude and duration (A20T10). Using A20T10 intermittent treatment, the production of biohydrogen could be maximized up to 14.438 mL H_2/mL_m_e_d_i_u_m with a COD_t_o_t_a_l removal and light efficiency of 52.2% and 7.412%, respectively. By comparing the treatment without intermittent ultrasonication, an increase of biohydrogen yield by 44.6% was achieved in A20T10 treatment. A total energy input of 306.1 J/mL (A20T10 treatment) was supplied to improve substrate consumption and light distribution during the photofermentation, which led to the increase of biohydrogen yield.

  4. Bioethanol, biohydrogen and biogas production from wheat straw in a biorefinery concept

    DEFF Research Database (Denmark)

    Kaparaju, Prasad Laxmi-Narasimha; Serrano, Maria; Thomsen, Anne Belinda

    2009-01-01

    fermentation of cellulose yielded 0.41 g-ethanol/g-glucose, while dark fermentation of hydrolysate produced 178.0 ml-H-2/g-sugars. The effluents from both bioethanol and biohydrogen processes were further used to produce methane with the yields of 0.324 and 0.381 m(3)/kg volatile solids (VS)added, respectively....... Additionally, evaluation of six different wheat straw-to-biofuel production scenaria showed that either use of wheat straw for biogas production or multi-fuel production were the energetically most efficient processes compared to production of mono-fuel such as bioethanol when fermenting C6 sugars alone. Thus...

  5. Biohydrogen production from rotten orange with immobilized mixed culture: Effect of immobilization media for various composition of substrates

    Energy Technology Data Exchange (ETDEWEB)

    Damayanti, Astrilia, E-mail: liasholehasd@gmail.com [Department of Chemical Engineering, Faculty of Engineering, Semarang State University, E1 Building, 2nd floor, Kampus Sekaran, Gunungpati, Semarang 50229 (Indonesia); Department of Chemical Engineering, Faculty of Engineering, Gadjah Mada University, Jl. Grafika No. 2, Kampus UGM, Yogyakarta 55281 (Indonesia); Sarto,; Syamsiah, Siti; Sediawan, Wahyudi B. [Department of Chemical Engineering, Faculty of Engineering, Gadjah Mada University, Jl. Grafika No. 2, Kampus UGM, Yogyakarta 55281 (Indonesia)

    2015-12-29

    Enriched–immobilized mixed culture was utilized to produce biohydrogen in mesophilic condition under anaerobic condition using rotten orange as substrate. The process was conducted in batch reactors for 100 hours. Microbial cultures from three different sources were subject to a series of enrichment and immobilized in two different types of media, i.e. calcium alginate (CA, 2%) and mixture of alginate and activated carbon (CAC, 1:1). The performance of immobilized culture in each media was tested for biohydrogen production using four different substrate compositions, namely orange meat (OM), orange meat added with peel (OMP), orange meat added with limonene (OML), and mixture of orange meat and peel added with limonene (OMPL). The results show that, with immobilized culture in CA, the variation of substrate composition gave significant effect on the production of biohydrogen. The highest production of biohydrogen was detected for substrate containing only orange meet, i.e. 2.5%, which was about 3-5 times higher than biohydrogen production from other compositions of substrate. The use of immobilized culture in CAC in general has increased the hydrogen production by 2-7 times depending on the composition of substrate, i.e. 5.4%, 4.8%, 5.1%, and 4.4% for OM, OMP, OML, and OMPL, respectively. The addition of activated carbon has eliminated the effect of inhibitory compounds in the substrate. The major soluble metabolites were acetic acid, propionic acid, and butyric acid.

  6. Biohydrogen production from rotten orange with immobilized mixed culture: Effect of immobilization media for various composition of substrates

    Science.gov (United States)

    Damayanti, Astrilia; Sarto, Syamsiah, Siti; Sediawan, Wahyudi B.

    2015-12-01

    Enriched-immobilized mixed culture was utilized to produce biohydrogen in mesophilic condition under anaerobic condition using rotten orange as substrate. The process was conducted in batch reactors for 100 hours. Microbial cultures from three different sources were subject to a series of enrichment and immobilized in two different types of media, i.e. calcium alginate (CA, 2%) and mixture of alginate and activated carbon (CAC, 1:1). The performance of immobilized culture in each media was tested for biohydrogen production using four different substrate compositions, namely orange meat (OM), orange meat added with peel (OMP), orange meat added with limonene (OML), and mixture of orange meat and peel added with limonene (OMPL). The results show that, with immobilized culture in CA, the variation of substrate composition gave significant effect on the production of biohydrogen. The highest production of biohydrogen was detected for substrate containing only orange meet, i.e. 2.5%, which was about 3-5 times higher than biohydrogen production from other compositions of substrate. The use of immobilized culture in CAC in general has increased the hydrogen production by 2-7 times depending on the composition of substrate, i.e. 5.4%, 4.8%, 5.1%, and 4.4% for OM, OMP, OML, and OMPL, respectively. The addition of activated carbon has eliminated the effect of inhibitory compounds in the substrate. The major soluble metabolites were acetic acid, propionic acid, and butyric acid.

  7. Biohydrogen production from rotten orange with immobilized mixed culture: Effect of immobilization media for various composition of substrates

    International Nuclear Information System (INIS)

    Damayanti, Astrilia; Sarto,; Syamsiah, Siti; Sediawan, Wahyudi B.

    2015-01-01

    Enriched–immobilized mixed culture was utilized to produce biohydrogen in mesophilic condition under anaerobic condition using rotten orange as substrate. The process was conducted in batch reactors for 100 hours. Microbial cultures from three different sources were subject to a series of enrichment and immobilized in two different types of media, i.e. calcium alginate (CA, 2%) and mixture of alginate and activated carbon (CAC, 1:1). The performance of immobilized culture in each media was tested for biohydrogen production using four different substrate compositions, namely orange meat (OM), orange meat added with peel (OMP), orange meat added with limonene (OML), and mixture of orange meat and peel added with limonene (OMPL). The results show that, with immobilized culture in CA, the variation of substrate composition gave significant effect on the production of biohydrogen. The highest production of biohydrogen was detected for substrate containing only orange meet, i.e. 2.5%, which was about 3-5 times higher than biohydrogen production from other compositions of substrate. The use of immobilized culture in CAC in general has increased the hydrogen production by 2-7 times depending on the composition of substrate, i.e. 5.4%, 4.8%, 5.1%, and 4.4% for OM, OMP, OML, and OMPL, respectively. The addition of activated carbon has eliminated the effect of inhibitory compounds in the substrate. The major soluble metabolites were acetic acid, propionic acid, and butyric acid

  8. Innovative self-powered submersible microbial electrolysis cell (SMEC) for biohydrogen production from anaerobic reactors

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2012-01-01

    A self-powered submersible microbial electrolysis cell (SMEC), in which a specially designed anode chamber and external electricity supply were not needed, was developed for in situ biohydrogen production from anaerobic reactors. In batch experiments, the hydrogen production rate reached 17.8 m...... improvement of voltage output and reduction of electron losses were essential for efficient hydrogen generation. In addition, alternate exchanging the electricity-assisting and hydrogen-producing function between the two cell units of the SMEC was found to be an effective approach to inhibit methanogens...

  9. One-carbon substrate-based biohydrogen production: microbes, mechanism, and productivity.

    Science.gov (United States)

    Rittmann, Simon K-M R; Lee, Hyun Sook; Lim, Jae Kyu; Kim, Tae Wan; Lee, Jung-Hyun; Kang, Sung Gyun

    2015-01-01

    Among four basic mechanisms for biological hydrogen (H2) production, dark fermentation has been considered to show the highest hydrogen evolution rate (HER). H2 production from one-carbon (C1) compounds such as formate and carbon monoxide (CO) is promising because formate is an efficient H2 carrier, and the utilization of CO-containing syngas or industrial waste gas may render the industrial biohydrogen production process cost-effective. A variety of microbes with the formate hydrogen lyase (FHL) system have been identified from phylogenetically diverse groups of archaea and bacteria, and numerous efforts have been undertaken to improve the HER for formate through strain optimization and bioprocess development. CO-dependent H2 production has been investigated to enhance the H2 productivity of various carboxydotrophs via an increase in CO gas-liquid mass transfer rates and the construction of genetically modified strains. Hydrogenogenic CO-conversion has been applied to syngas and by-product gas of the steel-mill process, and this low-cost feedstock has shown to be promising in the production of biomass and H2. Here, we focus on recent advances in the isolation of novel phylogenetic groups utilizing formate or CO, the remarkable genetic engineering that enhances H2 productivity, and the practical implementation of H2 production from C1 substrates. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Bio-hydrogen production from glycerol by a strain of Enterobacter aerogenes

    Energy Technology Data Exchange (ETDEWEB)

    Marques, P.A.S.S; Bartolomeu, M.L.; Tome, M.M.; Rosa, M.F. [INETI, Unit of Biomass/Renewable Energy Department, Estrada do Paco do Lumiar, 22, 1649-038 Lisboa (Portugal)

    2008-07-01

    The goal of this work was to evaluate the H2 production from glycerol-containing byproducts obtained from biodiesel industrial production, using Enterobacter aerogenes ATCC 13048 Sputum. H2 production using as substrate pure glycerol and glycerol-containing biodiesel byproducts was compared. The effect of parameters such as initial substrate concentration and sodium chloride addition on the bio-hydrogen production efficiency was also investigated. The results showed that using 10 g/L of pure glycerol or biodiesel residues, containing the same concentration of glycerol as substrate, lead to similar bio-hydrogen productions (3.46 LH2/L and 3.28 LH2/L fermentation medium, respectively). This indicates that the performance of the E. aerogenes strain used was not influenced by the presence of other components than glycerol in biodiesel residues, at least for the tested waste concentration range. When sodium chloride was added to the fermentation medium with pure 10 g/L glycerol, H2 production was not affected (3.34 LH2/L fermentation medium), showing that metabolism of the E. aerogenes strain was not inhibited by this biodiesel waste component up to 4 g/L chloride concentration. Biodiesel residues used without sterilization provided a higher H2 production (1.03 L) than the ones submitted to previous sterilization in autoclave (0.89 L).

  11. Optimizing the impact of temperature on bio-hydrogen production from food waste and its derivatives under no pH control using statistical modelling

    OpenAIRE

    Arslan, C.; Sattar, A.; Ji, C.; Sattar, S.; Yousaf, K.; Hashim, S.

    2015-01-01

    The effect of temperature on bio-hydrogen production by co-digestion of sewerage sludge with food waste and its two derivatives, i.e. noodle waste and rice waste, was investigated by statistical modelling. Experimental results showed that increasing temperature from mesophilic (37 °C) to thermophilic (55 °C) was an effective mean for increasing bio-hydrogen production from food waste and noodle waste, but it caused a negative impact on bio-hydrogen production from rice waste...

  12. Biohydrogen Production and Kinetic Modeling Using Sediment Microorganisms of Pichavaram Mangroves, India

    Directory of Open Access Journals (Sweden)

    P. Mullai

    2013-01-01

    Full Text Available Mangrove sediments host rich assemblages of microorganisms, predominantly mixed bacterial cultures, which can be efficiently used for biohydrogen production through anaerobic dark fermentation. The influence of process parameters such as effect of initial glucose concentration, initial medium pH, and trace metal (Fe2+ concentration was investigated in this study. A maximum hydrogen yield of 2.34, 2.3, and 2.6 mol H2 mol−1 glucose, respectively, was obtained under the following set of optimal conditions: initial substrate concentration—10,000 mg L−1, initial pH—6.0, and ferrous sulphate concentration—100 mg L−1, respectively. The addition of trace metal to the medium (100 mg L−1 FeSO4·7H2O enhanced the biohydrogen yield from 2.3 mol H2 mol−1 glucose to 2.6 mol H2 mol−1 glucose. Furthermore, the experimental data was subjected to kinetic analysis and the kinetic constants were estimated with the help of well-known kinetic models available in the literature, namely, Monod model, logistic model and Luedeking-Piret model. The model fitting was found to be in good agreement with the experimental observations, for all the models, with regression coefficient values >0.92.

  13. Enterobacter aerogenes metabolites enhance Microcystis aeruginosa biomass recovery for sustainable bioflocculant and biohydrogen production.

    Science.gov (United States)

    Xu, Liang; Zhou, Mo; Ju, Hanyu; Zhang, Zhenxing; Zhang, Jiquan; Sun, Caiyun

    2018-04-07

    We report a recycling bioresource involving harvesting of Microcystis aeruginosa using the bioflocculant (MBF-32) produced by Enterobacter aerogenes followed by the recovery of the harvested M. aeruginosa as the main substrate for the sustainable production of MBF-32 and biohydrogen. The experimental results indicate that the efficiency of bioflocculation exceeded 90% under optimal conditions. The harvested M. aeruginosa was further recycled as the main substrate for the supply of necessary elements. The highest yield (3.6±0.1g/L) of MBF-32 could be obtained from 20g/L of wet biomass of M. aeruginosa with an additional 20g/L of glucose as the extra carbon source. The highest yield of biohydrogen was 35mL of H 2 /g (dw) algal biomass, obtained from 20g/L of wet biomass of M. aeruginosa with an additional 10g/L of glycerol. Transcriptome analyses indicated that MBF-32 was mainly composed of polysaccharide and tyrosine/tryptophan proteins. Furthermore, NADH synthase and polysaccharide export-related genes were found to be up-regulated. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Biohydrogen production from co-digestion of high carbohydrate containing food waste and combined primary and secondary sewage sludge

    International Nuclear Information System (INIS)

    Arain, M.; Sahito, R.

    2018-01-01

    In this paper, FW (Food Waste) and SS (Sewage Sludge) were co-digested for biohydrogen production. After characterization both FW and SS were found as better option for biohydrogen production. FW was rich in carbohydrate containing specially rice, which was added as more than 50% and easily hydrolyzable waste. FW is considered as an auxiliary substrate for biohydrogen production and high availability of carbohydrate in FW makes it an important substrate for the production of biohydrogen. On the contrary, SS was rich in protein and has a high pH buffering capacity, which makes it appropriate for codigestion. Adequate supplementation of inorganic salts, the addition of hydrogen producing inoculums, protein enrichment and pH buffering capacity of SS and carbohydrate content in FW increases the hydrogen production potential. Various experiments were performed by considering different mixing ratios like 90:10, 80:20, 70:30, 60:40 and 50:50 of FW and SS. The 50:50 and 90:10 mixing ratio of FW and SS were found as best among all other co-digested ratios. The maximum specific hydrogen yield 106.7 mL/gVS added was obtained at a waste composition of 50:50 followed by 92.35 mL/gVS added from 90:10 of FW to SS. The optimum pH and temperature for operating this process were in the range of 5.5-6.5 and 35°C. The production of clean energy and waste utilization in anaerobic co-digestion process makes biohydrogen generation a promising and novel approach to fulfilling the increasing energy needs as a substitute for fossil fuels. (author)

  15. Timeline of bio-hydrogen production by anaerobic digestion of biomass

    Directory of Open Access Journals (Sweden)

    Bernadette E. TELEKY

    2015-12-01

    Full Text Available Anaerobic digestion of biomass is a process capable to produce biohydrogen, a clean source of alternative energy. Lignocellulosic biomass from agricultural waste is considered a renewable energy source; therefore its utilization also contributes to the reduction of water, soil and air pollution. The study consists in five consecutive experiments designed to utilize anaerobic bacterial enrichment cultures originating from the Hungarian Lake, Hévíz. Wheat straw was used as complex substrate to produce hydrogen. The timeline evolution of hydrogen production was analyzed and modelled by two functions: Logistic and Boltzmann. The results proved that hydrogen production is significant, with a maximum of 0.24 mlN/ml and the highest hydrogen production occurs between the days 4-10 of the experiment.

  16. The influence of calcium supplementation on immobilised mixed microflora for biohydrogen production

    Science.gov (United States)

    Lutpi, Nabilah Aminah; Shian, Wong Yee; Izhar, Tengku Nuraiti Tengku; Zainol, Noor Ainee; Kiong, Yiek Wee

    2017-04-01

    This study is aim to study the effect of calcium as supplement in attached growth system towards the enhancement of the hydrogen production performance. The effects of calcium ion for thermophilic biohydrogen production were studied by using a mixed culture, from palm oil mill effluent sludge and granular activated carbon (GAC) as the support material. Batch experiments were carried out at 60°C by feeding the anaerobic sludge bacteria with sucrose-containing synthetic medium at an initial pH of 5.5 under anaerobic conditions. The repeated batch cultivation process was conducted by adding different concentration of calcium at range 0.025g/L to 0.15g/L. The results showed that the calcium at 0.1 g/L was the optimal concentration to enhance the fermentative hydrogen production under thermophilic (60°C) conditions.

  17. Advances in biohydrogen production processes: An approach towards commercialization

    Energy Technology Data Exchange (ETDEWEB)

    Das, Debabrata [Department of Biotechnology, Indian Institute of Technology, Kharagpur 721302, West Bengal (India)

    2009-09-15

    Biological H{sub 2} production has an edge over its chemical counterpart mainly because it is environmentally benign. Despite having simpler technology, higher evolution rate of H{sub 2} and the wide spectrum of substrate utilization, the major deterrent of anaerobic dark fermentation process stems from its lower achievable yields. Theoretically, the maximum H{sub 2} yield is 4 mol H{sub 2}/mol glucose when glucose is completely metabolized to acetate or acetone in the anaerobic process. But it is somewhat difficult to achieve the complete degradation of glucose to carbon dioxide and H{sub 2} through anaerobic dark fermentation. Moreover, this yield appears too low to be economically viable as an alternative to the existing chemical or electrochemical processes of hydrogen generation. Intensive research studies have already been carried out on the advancement of these processes, such as the development of genetically modified microorganism, improvement of the reactor designs, use of different solid matrices for the immobilization of whole cells, development of two-stage processes, and higher H{sub 2} production rates. Maximum H{sub 2} yield is found to be 5.1 mol H{sub 2}/mol glucose. However, major bottlenecks for the commercialization of these processes are lower H{sub 2} yield and rate of H{sub 2} production. Competent microbial cultures are required to handle waste materials efficiently, which are usually complex in nature. This will serve dual purposes: clean energy generation and bioremediation. Scale-up studies on fermentative H{sub 2} production processes have been done successfully. Pilot plant trials of the photo-fermentation processes require more attention. Use of cheaper raw materials and efficient biological H{sub 2} production processes will surely make them more competitive with the conventional H{sub 2} generation processes in near future. (author)

  18. Reverse micelles as suitable microreactor for increased biohydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, Anjana [Nanotechnology and Molecular Biology Laboratory, Centre of Biotechnology, University of Allahabad, Allahabad 211002 (India); Pandey, Ashutosh [Centre of Energy Studies, MNNIT, Allahabad 211004 (India)

    2008-01-15

    Reverse micelles have been shown to act as efficient microreactors for enzymic reactions and whole cell entrapment in organic (non-aqueous) media wherein the reactants are protected from denaturation by the surrounding organic solvent. These micelles are thermodynamically stable, micrometer sized water droplets dispersed in an organic phase by a surfactant. It has been observed that when whole cells of photosynthetic bacteria (Rhodopseudomonas sphaeroides or Rhodobacter sphaeroides 2.4.1) are entrapped inside these reverse micelles, the H{sub 2} production enhanced from 25 to 35 folds. That is, 1.71mmol(mgprotein){sup -1}h{sup -1} in case of R. sphaeroides which is 25 fold higher in benzene-sodium lauryl sulfate reverse micelles. Whereas, in case of R. sphaeroides 2.4.1 the H{sub 2} production was increased by 35 fold within AOT-isooctane reverse micelles i.e. 11.5mmol(mgprotein){sup -1}h{sup -1}. The observations indicate that the entrapment of whole cells of microbes within reverse micelles provides a novel and efficient technique to produce hydrogen by the inexhaustible biological route. The two microorganisms R. sphaeroides 2.4.1 (a photosynthetic bacteria) and Citrobacter Y19 (a facultative anaerobic bacteria) together are also entrapped within AOT-isooctane and H{sub 2} production was measured i.e. 69mmol(mgprotein){sup -1}h{sup -1}. The nitrogenase enzyme responsible for hydrogen production by R. sphaeroides/R. sphaeroides 2.4.1 cells is oxygen sensitive, and very well protected within reverse micelles by the use of combined approach of two cells (R. sphaeroides 2.4.1 and Citrobacter Y19). In this case glucose present in the medium of Citrobacter Y19 serves double roles in enhancing the sustained production rate of hydrogen. Firstly, it quenches the free O{sub 2}liberated as a side product of reaction catalyzed by nitrogenase, which is O{sub 2} labile. Secondly, organic acid produced by this reaction is utilized by the Citrobacter Y19 as organic substrate in

  19. Development of Technology and Installation for Biohydrogen Production

    Science.gov (United States)

    Pridvizhkin, S. V.; Vyguzova, M. A.; Bazhenov, O. V.

    2017-11-01

    The article discusses the method for hydrogen production and the device this method application. The relevance of the use of renewable fuels and the positive impact of renewable energy on the environment and the economy is also considered. The presented technology relates to a method for hydrogen production from organic materials subject to anaerobic fermentation, such as the components of solid municipal waste, sewage sludge and agricultural enterprises wastes, sewage waste. The aim of the research is to develop an effective eco-friendly technology for hydrogen producing within an industrial project To achieve the goal, the following issues have been addressed in the course of the study: - development of the process schemes for hydrogen producing from organic materials; - development of the technology for hydrogen producing; - optimization of a biogas plant with the aim of hydrogen producing at one of the fermentation stages; - approbation of the research results. The article is recommended for engineers and innovators working on the renewable energy development issues.

  20. Biohydrogen production from diary processing wastewater by anaerobic biofilm reactors

    Energy Technology Data Exchange (ETDEWEB)

    Rios-Gonzalez, L.J.; Moreno-Davila, I.M.; Rodriguez-Martinez, J.; Garza-Garcia, Y. [Universidad Autonoma de Coahuila, Saltillo, Coahuila (Mexico)]. E-mail: leopoldo.rios@mail.uadec.mx

    2009-09-15

    This article describes biological hydrogen production from diary wastewater via anaerobic fermentation using pretreated heat shock (100 degrees Celsius, 30 min.) and acid (pH 3.0, 24 h) treatment procedures to selectively enrich the hydrogen producing mixed consortia prior to inoculation to batch reactors. Bioreactor used for immobilization consortia was operated at mesophilic (room) temperature (20{+-}3 degrees Celsius), under acidophilic conditions (pH 4.0-4.5), HRT (2h), and a natural support for generate hydrogen producing mixed consortia biofilm: Opuntia imbricata. Reactor was initially operated with sorbitol (5g/L) for 60 days of operation. Batch tests were conducted using 20{+-}0.02g of natural support with biofilm. Batch experiments were conducted to investigate the effect of COD (2.9-21.1 g-COD/L), at initial pH of 7.0, 32{+-}1 degrees Celsius. Maximum hydrogen yield was obtained at 21.1 g-COD/L. Experiments of pH effect were conducted using the optimal substrate concentration (21.2 g-COD/L), at pH 4 to 7 and 11.32 (pH diary wastewater) ,and 32{+-}1 degrees Celsius. Experiments results indicate the optimum initial cultivation was pH 4.0, but we can consider also a stable hydrogen production at pH 11.32 (pH diary wastewater), so we can avoid to fit the pH, and use diary wastewater as it left the process of cheese manufacture. The operational pH of 4.0 is 1.5 units below that of previously reported hydrogen producing organisms. The influence of the effect of temperature were conducted using the optimal substrate concentration (21.2 g-COD/L), two pH levels: 4.0 and 11.32, and four different temperatures: 16{+-}3 degrees Celsius (room temperature), 3 C, 45{+-}1 degrees Celsius y 55{+-}1 degrees Celsius.Optimal temperature for hydrogen production from diary wastewater at pH 4.0 was 55{+-}1 degrees Celsius, and for pH 11.32 was 16{+-}3 degrees Celsius.Therefore, the results suggests biofilm reactors in a natural support like Opuntia imbricata have good potential

  1. Bayesian Computational Approaches for Gene Regulation Studies of Bioethanol and Biohydrogen Production. Final Scientific/Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Newberg, Lee; McCue, Lee Anne; Van Roey, Patrick

    2014-04-17

    The project developed mathematical models and first-version software tools for the understanding of gene regulation across multiple related species. The project lays the foundation for understanding how certain alpha-proteobacterial species control their own genes for bioethanol and biohydrogen production, and sets the stage for exploiting bacteria for the production of fuels. Enabling such alternative sources of fuel is a high priority for the Department of Energy and the public.

  2. Hydrogen production from sugar beet juice using an integrated biohydrogen process of dark fermentation and microbial electrolysis cell.

    Science.gov (United States)

    Dhar, Bipro Ranjan; Elbeshbishy, Elsayed; Hafez, Hisham; Lee, Hyung-Sool

    2015-12-01

    An integrated dark fermentation and microbial electrochemical cell (MEC) process was evaluated for hydrogen production from sugar beet juice. Different substrate to inoculum (S/X) ratios were tested for dark fermentation, and the maximum hydrogen yield was 13% of initial COD at the S/X ratio of 2 and 4 for dark fermentation. Hydrogen yield was 12% of initial COD in the MEC using fermentation liquid end products as substrate, and butyrate only accumulated in the MEC. The overall hydrogen production from the integrated biohydrogen process was 25% of initial COD (equivalent to 6 mol H2/mol hexoseadded), and the energy recovery from sugar beet juice was 57% using the combined biohydrogen. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Bio-hydrogen production by Enterobacter asburiae SNU-1 isolated from a landfill

    Energy Technology Data Exchange (ETDEWEB)

    Jong-Hwan Shin; Jong Hyun Yoon; Tai Hyun Park [School of Chemical and Biological Engineering, Seoul National University, Seoul 151-744, (Korea, Republic of)

    2006-07-01

    A new fermentative hydrogen-producing bacterium was isolated from a landfill, and it was identified as Enterobacter asburiae strain using a genomic DNA hybridization method. Environmental factors and metabolic flux influencing the hydrogen production were investigated, including pH, initial glucose and formate concentrations. The major hydrogen production pathway of this strain is considered to be a formate pathway by using formate hydrogen lyase (FHL). Optimum pH for the hydrogen production was pH 7.0 in PYG medium, at which hydrogen production/unit volume and overall hydrogen productivity were 2615 ml/l and 174 ml H{sub 2}/l/hr, respectively, at 25 g glucose/l. The maximum hydrogen productivity was estimated to be 417 ml H{sub 2}/l/hr at 15 g glucose/l. This strain produced bio-hydrogen mostly in the stationary phase, in which formate concentration was high. In this paper, hydrogen production was tried in formate medium after cell harvest. (authors)

  4. Bio-hydrogen production by Enterobacter asburiae SNU-1 isolated from a landfill

    International Nuclear Information System (INIS)

    Jong-Hwan Shin; Jong Hyun Yoon; Tai Hyun Park

    2006-01-01

    A new fermentative hydrogen-producing bacterium was isolated from a landfill, and it was identified as Enterobacter asburiae strain using a genomic DNA hybridization method. Environmental factors and metabolic flux influencing the hydrogen production were investigated, including pH, initial glucose and formate concentrations. The major hydrogen production pathway of this strain is considered to be a formate pathway by using formate hydrogen lyase (FHL). Optimum pH for the hydrogen production was pH 7.0 in PYG medium, at which hydrogen production/unit volume and overall hydrogen productivity were 2615 ml/l and 174 ml H 2 /l/hr, respectively, at 25 g glucose/l. The maximum hydrogen productivity was estimated to be 417 ml H 2 /l/hr at 15 g glucose/l. This strain produced bio-hydrogen mostly in the stationary phase, in which formate concentration was high. In this paper, hydrogen production was tried in formate medium after cell harvest. (authors)

  5. Feasibility of biohydrogen production from industrial wastes using defined microbial co-culture

    Directory of Open Access Journals (Sweden)

    Peng Chen

    2015-01-01

    Full Text Available BACKGROUND: The development of clean or novel alternative energy has become a global trend that will shape the future of energy. In the present study, 3 microbial strains with different oxygen requirements, including Clostridium acetobutylicum ATCC 824, Enterobacter cloacae ATCC 13047 and Kluyveromyces marxianus 15D, were used to construct a hydrogen production system that was composed of a mixed aerobic-facultative anaerobic-anaerobic consortium. The effects of metal ions, organic acids and carbohydrate substrates on this system were analyzed and compared using electrochemical and kinetic assays. It was then tested using small-scale experiments to evaluate its ability to convert starch in 5 L of organic wastewater into hydrogen. For the one-step biohydrogen production experiment, H1 medium (nutrient broth and potato dextrose broth was mixed directly with GAM broth to generate H2 medium (H1 medium and GAM broth. Finally, Clostridium acetobutylicum ATCC 824, Enterobacter cloacae ATCC 13047 and Kluyveromyces marxianus 15D of three species microbial co-culture to produce hydrogen under anaerobic conditions. For the two-step biohydrogen production experiment, the H1 medium, after cultured the microbial strains Enterobacter cloacae ATCC 13047 and Kluyveromyces marxianus 15D, was centrifuged to remove the microbial cells and then mixed with GAM broth (H2 medium. Afterward, the bacterial strain Clostridium acetobutylicum ATCC 824 was inoculated into the H2 medium to produce hydrogen by anaerobic fermentation. RESULTS: The experimental results demonstrated that the optimum conditions for the small-scale fermentative hydrogen production system were at pH 7.0, 35°C, a mixed medium, including H1 medium and H2 medium with 0.50 mol/L ferrous chloride, 0.50 mol/L magnesium sulfate, 0.50 mol/L potassium chloride, 1% w/v citric acid, 5% w/v fructose and 5% w/v glucose. The overall hydrogen production efficiency in the shake flask fermentation group was 33.7 m

  6. Potential use and the energy conversion efficiency analysis of fermentation effluents from photo and dark fermentative bio-hydrogen production.

    Science.gov (United States)

    Zhang, Zhiping; Li, Yameng; Zhang, Huan; He, Chao; Zhang, Quanguo

    2017-12-01

    Effluent of bio-hydrogen production system also can be adopted to produce methane for further fermentation, cogeneration of hydrogen and methane will significantly improve the energy conversion efficiency. Platanus Orientalis leaves were taken as the raw material for photo- and dark-fermentation bio-hydrogen production. The resulting concentrations of acetic, butyric, and propionic acids and ethanol in the photo- and dark-fermentation effluents were 2966mg/L and 624mg/L, 422mg/L and 1624mg/L, 1365mg/L and 558mg/L, and 866mg/L and 1352mg/L, respectively. Subsequently, we calculated the energy conversion efficiency according to the organic contents of the effluents and their energy output when used as raw material for methane production. The overall energy conversion efficiencies increased by 15.17% and 22.28%, respectively, when using the effluents of photo and dark fermentation. This two-step bio-hydrogen and methane production system can significantly improve the energy conversion efficiency of anaerobic biological treatment plants. Copyright © 2017. Published by Elsevier Ltd.

  7. Feasibility study on the application of rhizosphere microflora of rice for the biohydrogen production from wasted bread

    Energy Technology Data Exchange (ETDEWEB)

    Doi, Tetsuya [Field Production Science Center, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Nishitokyo, Tokyo 188-0002 (Japan); Nishihara Environment Technology Inc., Tokyo 108-0023 (Japan); Matsumoto, Hisami [Nishihara Environment Technology Inc., Tokyo 108-0023 (Japan); Abe, Jun [AE-Bio, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo 113-8657 (Japan); Morita, Shigenori [Field Production Science Center, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Nishitokyo, Tokyo 188-0002 (Japan)

    2009-02-15

    We performed an experiment of continuous anaerobic hydrogen fermentation as a pilot-plant-scale test, in which waste from a bread factory was fermented by microflora of rice rhizosphere origin. The community structure of microflora during anaerobic hydrogen fermentation was analyzed using PCR-DGGE, FISH, and quinone profiles. The relation of those results to hydrogen generation was discussed. Results show that a suitable condition was a reactor temperature of 35 C, with HRT 12-36 h, volume load of 30-70 kg-COD{sub Cr}/m{sup 3} day, and maximum hydrogen production rate of 1.30 mol-H{sub 2}/mol-hexose. Regarding characteristics of microflora during fermentation, PCR-DGGE results show specific 16S rDNA band patterns; Megasphaera elsdenii and Clostridium sp. of the hydrogen-producing bacteria were identified. M. elsdenii was detected throughout the fermentation period, while Clostridium sp. of hydrogen-producing bacteria was detected on the 46th day. Furthermore, FISH revealed large amounts of Clostridium spp. in the sample. The quinone profile showed that the dominant molecular species of quinone is MK-7. Because Clostridium spp. belong to MK-7, results suggest that the quinone profile result agrees with the results of PCR-DGGE and FISH. Microflora in the rhizosphere of rice plants can be a possible resource for effective bacteria of biohydrogen production. (author)

  8. Production of biohydrogen by recombinant expression of [NiFe]-hydrogenase 1 in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Kim Jaoon YH

    2010-07-01

    Full Text Available Abstract Background Hydrogenases catalyze reversible reaction between hydrogen (H2 and proton. Inactivation of hydrogenase by exposure to oxygen is a critical limitation in biohydrogen production since strict anaerobic conditions are required. While [FeFe]-hydrogenases are irreversibly inactivated by oxygen, it was known that [NiFe]-hydrogenases are generally more tolerant to oxygen. The physiological function of [NiFe]-hydrogenase 1 is still ambiguous. We herein investigated the H2 production potential of [NiFe]-hydrogenase 1 of Escherichia coli in vivo and in vitro. The hyaA and hyaB genes corresponding to the small and large subunits of [NiFe]-hydrogenase 1 core enzyme, respectively, were expressed in BL21, an E. coli strain without H2 producing ability. Results Recombinant BL21 expressing [NiFe]-hydrogenase 1 actively produced H2 (12.5 mL H2/(h·L in 400 mL glucose minimal medium under micro-aerobic condition, whereas the wild type BL21 did not produce H2 even when formate was added as substrate for formate hydrogenlyase (FHL pathway. The majority of recombinant protein was produced as an insoluble form, with translocation of a small fraction to the membrane. However, the membrane fraction displayed high activity (~65% of total cell fraction, based on unit protein mass. Supplement of nickel and iron to media showed these metals contribute essentially to the function of [NiFe]-hydrogenase 1 as components of catalytic site. In addition, purified E. coli [NiFe]-hydrogenase 1 using his6-tag displayed oxygen-tolerant activity of ~12 nmol H2/(min·mg protein under a normal aeration environment, compared to [FeFe]-hydrogenase, which remains inactive under this condition. Conclusions This is the first report on physiological function of E. coli [NiFe]-hydrogenase 1 for H2 production. We found that [NiFe]-hydrogenase 1 has H2 production ability even under the existence of oxygen. This oxygen-tolerant property is a significant advantage because it is

  9. Feasibility of bio-hydrogen production from sewage sludge using defined microbial consortium

    Energy Technology Data Exchange (ETDEWEB)

    Shireen Meher Kotay; Debabrata Das [Fermentation Technology Lab., Department of Biotechnology, Indian Institute of Technology Kharagpur, W.B., INDIA-721302 (India)

    2006-07-01

    Biological hydrogen production potential of a defined microbial consortium consisting of three facultative anaerobes, Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1 was studied. In this investigation their individual and combinatorial H{sub 2} production capabilities have been studied on defined media and pretreated sewage sludge. Defined medium, MYG (1% w/v Malt extract, 0.4% w/v yeast extract and 1% w/v glucose) with glucose as limiting substrate has been found to be most suitable for hydrogen production. Individually E. cloacae clearly gave higher yield (276 ml H{sub 2}/ g COD reduced) using defined medium than the other two strains. There was no considerable difference in maximal yield of hydrogen from individual and combinatorial (1:1:1 consortium) modes suggesting that E. cloacae dominated in the consortia on defined medium. Contradictorily, B. coagulans gave better bio-hydrogen yield (37.16 ml H{sub 2}/g COD consumed) than the other two strains when activated sewage sludge was used as substrate. The pretreatment of sludge included sterilization, (15% v/v) dilution and supplementation with 0.5%w/v glucose which was found to be essential to screen out the hydrogen consuming bacteria and ameliorate the hydrogenation. Considering (1:1:1) consortium as inoculum, interestingly yield of hydrogen was recorded to increase to 41.23 ml H{sub 2}/ g COD reduced inferring that in consortium, the substrate utilization was significantly higher. The hydrogen yield from pretreated sludge obtained in this study (35.54 ml H{sub 2} g sludge) has been found to be distinctively higher than the earlier reports (8.1 - 16.9 ml H{sub 2}/g sludge). However it was lower compared to the yield obtained from co-digestion of (83:17) food waste and sewage sludge (122 ml H{sub 2}/g carbohydrate COD). Employing formulated microbial consortia for bio-hydrogen production from sewage sludge was an attempt to augment the hydrogen yield from sludge

  10. Feasibility of bio-hydrogen production from sewage sludge using defined microbial consortium

    Energy Technology Data Exchange (ETDEWEB)

    Shireen Meher Kotay; Debabrata Das [Fermentation Technology Lab., Department of Biotechnology, Indian Institute of Technology Kharagpur, W.B., INDIA-721302 (India)

    2006-07-01

    Biological hydrogen production potential of a defined microbial consortium consisting of three facultative anaerobes, Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1 was studied. In this investigation their individual and combinatorial H{sub 2} production capabilities have been studied on defined media and pretreated sewage sludge. Defined medium, MYG (1% w/v Malt extract, 0.4% w/v yeast extract and 1% w/v glucose) with glucose as limiting substrate has been found to be most suitable for hydrogen production. Individually E. cloacae clearly gave higher yield (276 ml H{sub 2}/ g COD reduced) using defined medium than the other two strains. There was no considerable difference in maximal yield of hydrogen from individual and combinatorial (1:1:1 consortium) modes suggesting that E. cloacae dominated in the consortia on defined medium. Contradictorily, B. coagulans gave better bio-hydrogen yield (37.16 ml H{sub 2}/ g COD consumed) than the other two strains when activated sewage sludge was used as substrate. The pretreatment of sludge included sterilization, (15% v/v) dilution and supplementation with 0.5% w/v glucose which was found to be essential to screen out the hydrogen consuming bacteria and ameliorate the hydrogenation. Considering (1:1:1) consortium as inoculum, interestingly yield of hydrogen was recorded to increase to 41.23 ml H{sub 2}/ g COD reduced inferring that in consortium, the substrate utilization was significantly higher. The hydrogen yield from pretreated sludge obtained in this study (35.54 ml H{sub 2}/ g sludge) has been found to be distinctively higher than the earlier reports (8.1 - 16.9 ml H{sub 2} / g sludge). However it was lower compared to the yield obtained from co-digestion of (83:17) food waste and sewage sludge (122 ml H{sub 2}/ g carbohydrate COD). Employing formulated microbial consortia for bio-hydrogen production from sewage sludge was an attempt to augment the hydrogen yield from

  11. Feasibility of bio-hydrogen production from sewage sludge using defined microbial consortium

    International Nuclear Information System (INIS)

    Shireen Meher Kotay; Debabrata Das

    2006-01-01

    Biological hydrogen production potential of a defined microbial consortium consisting of three facultative anaerobes, Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1 was studied. In this investigation their individual and combinatorial H 2 production capabilities have been studied on defined media and pretreated sewage sludge. Defined medium, MYG (1% w/v Malt extract, 0.4% w/v yeast extract and 1% w/v glucose) with glucose as limiting substrate has been found to be most suitable for hydrogen production. Individually E. cloacae clearly gave higher yield (276 ml H 2 / g COD reduced) using defined medium than the other two strains. There was no considerable difference in maximal yield of hydrogen from individual and combinatorial (1:1:1 consortium) modes suggesting that E. cloacae dominated in the consortia on defined medium. Contradictorily, B. coagulans gave better bio-hydrogen yield (37.16 ml H 2 /g COD consumed) than the other two strains when activated sewage sludge was used as substrate. The pretreatment of sludge included sterilization, (15% v/v) dilution and supplementation with 0.5%w/v glucose which was found to be essential to screen out the hydrogen consuming bacteria and ameliorate the hydrogenation. Considering (1:1:1) consortium as inoculum, interestingly yield of hydrogen was recorded to increase to 41.23 ml H 2 / g COD reduced inferring that in consortium, the substrate utilization was significantly higher. The hydrogen yield from pretreated sludge obtained in this study (35.54 ml H 2 g sludge) has been found to be distinctively higher than the earlier reports (8.1 - 16.9 ml H 2 /g sludge). However it was lower compared to the yield obtained from co-digestion of (83:17) food waste and sewage sludge (122 ml H 2 /g carbohydrate COD). Employing formulated microbial consortia for bio-hydrogen production from sewage sludge was an attempt to augment the hydrogen yield from sludge. (authors)

  12. Feasibility of bio-hydrogen production from sewage sludge using defined microbial consortium

    International Nuclear Information System (INIS)

    Shireen Meher Kotay; Debabrata Das

    2006-01-01

    Biological hydrogen production potential of a defined microbial consortium consisting of three facultative anaerobes, Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1 was studied. In this investigation their individual and combinatorial H 2 production capabilities have been studied on defined media and pretreated sewage sludge. Defined medium, MYG (1% w/v Malt extract, 0.4% w/v yeast extract and 1% w/v glucose) with glucose as limiting substrate has been found to be most suitable for hydrogen production. Individually E. cloacae clearly gave higher yield (276 ml H 2 / g COD reduced) using defined medium than the other two strains. There was no considerable difference in maximal yield of hydrogen from individual and combinatorial (1:1:1 consortium) modes suggesting that E. cloacae dominated in the consortia on defined medium. Contradictorily, B. coagulans gave better bio-hydrogen yield (37.16 ml H 2 / g COD consumed) than the other two strains when activated sewage sludge was used as substrate. The pretreatment of sludge included sterilization, (15% v/v) dilution and supplementation with 0.5% w/v glucose which was found to be essential to screen out the hydrogen consuming bacteria and ameliorate the hydrogenation. Considering (1:1:1) consortium as inoculum, interestingly yield of hydrogen was recorded to increase to 41.23 ml H 2 / g COD reduced inferring that in consortium, the substrate utilization was significantly higher. The hydrogen yield from pretreated sludge obtained in this study (35.54 ml H 2 / g sludge) has been found to be distinctively higher than the earlier reports (8.1 - 16.9 ml H 2 / g sludge). However it was lower compared to the yield obtained from co-digestion of (83:17) food waste and sewage sludge (122 ml H 2 / g carbohydrate COD). Employing formulated microbial consortia for bio-hydrogen production from sewage sludge was an attempt to augment the hydrogen yield from sludge. (authors)

  13. Optimization of biohydrogen production from beer lees using anaerobic mixed bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Maojin; Yuan, Zhuliang; Zhi, Xiaohua; Shen, Jianquan [Beijing National Laboratory for Molecular Sciences (BNLMS), Laboratory of New Materials, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun North First Street 2, Beijing 100190 (China)

    2009-10-15

    Beer lees are the main by-product of the brewing industry. Biohydrogen production from beer lees using anaerobic mixed bacteria was investigated in this study, and the effects of acidic pretreatment, initial pH value and ferrous iron concentration on hydrogen production were studied at 35 C in batch experiments. The hydrogen yield was significantly enhanced by optimizing environmental factors such as hydrochloric acid (HCl) pretreatment of substrate, initial pH value and ferrous iron concentration. The optimal environmental factors of substrate pretreated with 2% HCl, pH = 7.0 and 113.67 mg/l Fe{sup 2+} were observed. A maximum cumulative hydrogen yield of 53.03 ml/g-dry beer lees was achieved, which was approximately 17-fold greater than that in raw beer lees. In addition, the degradation efficiency of the total reducing sugar, and the contents of hemicellulose, cellulose, lignin and metabolites are presented, which showed a strong dependence on the environmental factors. (author)

  14. Biohydrogen Production by the Thermophilic Bacterium Caldicellulosiruptor saccharolyticus: Current Status and Perspectives

    Directory of Open Access Journals (Sweden)

    Servé W. M. Kengen

    2013-01-01

    Full Text Available Caldicellulosiruptor saccharolyticus is one of the most thermophilic cellulolytic organisms known to date. This Gram-positive anaerobic bacterium ferments a broad spectrum of mono-, di- and polysaccharides to mainly acetate, CO2 and hydrogen. With hydrogen yields approaching the theoretical limit for dark fermentation of 4 mol hydrogen per mol hexose, this organism has proven itself to be an excellent candidate for biological hydrogen production. This review provides an overview of the research on C. saccharolyticus with respect to the hydrolytic capability, sugar metabolism, hydrogen formation, mechanisms involved in hydrogen inhibition, and the regulation of the redox and carbon metabolism. Analysis of currently available fermentation data reveal decreased hydrogen yields under non-ideal cultivation conditions, which are mainly associated with the accumulation of hydrogen in the liquid phase. Thermodynamic considerations concerning the reactions involved in hydrogen formation are discussed with respect to the dissolved hydrogen concentration. Novel cultivation data demonstrate the sensitivity of C. saccharolyticus to increased hydrogen levels regarding substrate load and nitrogen limitation. In addition, special attention is given to the rhamnose metabolism, which represents an unusual type of redox balancing. Finally, several approaches are suggested to improve biohydrogen production by C. saccharolyticus.

  15. Production of bioelectricity, bio-hydrogen, high value chemicals and bioinspired nanomaterials by electrochemically active biofilms.

    Science.gov (United States)

    Kalathil, Shafeer; Khan, Mohammad Mansoob; Lee, Jintae; Cho, Moo Hwan

    2013-11-01

    Microorganisms naturally form biofilms on solid surfaces for their mutual benefits including protection from environmental stresses caused by contaminants, nutritional depletion or imbalances. The biofilms are normally dangerous to human health due to their inherited robustness. On the other hand, a recent study suggested that electrochemically active biofilms (EABs) generated by electrically active microorganisms have properties that can be used to catalyze or control the electrochemical reactions in a range of fields, such as bioenergy production, bioremediation, chemical/biological synthesis, bio-corrosion mitigation and biosensor development. EABs have attracted considerable attraction in bioelectrochemical systems (BESs), such as microbial fuel cells and microbial electrolysis cells, where they act as living bioanode or biocathode catalysts. Recently, it was reported that EABs can be used to synthesize metal nanoparticles and metal nanocomposites. The EAB-mediated synthesis of metal and metal-semiconductor nanocomposites is expected to provide a new avenue for the greener synthesis of nanomaterials with high efficiency and speed than other synthetic methods. This review covers the general introduction of EABs, as well as the applications of EABs in BESs, and the production of bio-hydrogen, high value chemicals and bio-inspired nanomaterials. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Biohydrogen production from renewable agri-waste blend: Optimization using mixer design

    Energy Technology Data Exchange (ETDEWEB)

    Prakasham, R.S.; Sathish, T.; Brahmaiah, P.; Subba Rao, Ch. [Bioengineering and Environmental Center, Indian Institute of Chemical Technology, Hyderabad 500 607 (India); Sreenivas Rao, R.; Hobbs, Phil J. [North-Wyke Research, Okehampton, Devon EX20 2SB (United Kingdom)

    2009-08-15

    Biohydrogen from untreated mixed renewable agri-waste using buffalo dung compost is reported. Corn husk (CH) supported 25% higher hydrogen (H{sub 2}) production and showed the maximum value (62.38%) with p value (1.2 x 10{sup -6}) revealing its significance at individual and interactive level, respectively, compared to ground nut shell (GNS) and rice husk (RH). Augmented-simplex-lattice design experimentation revealed that a partial supplementation of RH or GNS to CH improves H{sub 2} yield. Multiple-linear-regression analysis indicated that a quadratic model (low p = 0.0023, high F value = 35.99 and R{sup 2}{sub quadratic} = 0.99) was more significant compared to other (linear, cubic and special cubic) models. Acetate and butyrate were accounted >80% of the volatile fatty acids (VFAs). A maximum accumulation of 65.78 ml H{sub 2} g{sup -1} TVS was produced using agri-wastes in the ratio of CH:RH:GNS = 70:16:12. (author)

  17. Biohydrogen production by dark fermentation of glycerol using Enterobacter and Citrobacter Sp.

    Science.gov (United States)

    Maru, Biniam T; Constanti, Magda; Stchigel, Alberto M; Medina, Francesc; Sueiras, Jesus E

    2013-01-01

    Glycerol is an attractive substrate for biohydrogen production because, in theory, it can produce 3 mol of hydrogen per mol of glycerol. Moreover, glycerol is produced in substantial amounts as a byproduct of producing biodiesel, the demand for which has increased in recent years. Therefore, hydrogen production from glycerol was studied by dark fermentation using three strains of bacteria: namely, Enterobacter spH1, Enterobacter spH2, and Citrobacter freundii H3 and a mixture thereof (1:1:1). It was found that, when an initial concentration of 20 g/L of glycerol was used, all three strains and their mixture produced substantial amounts of hydrogen ranging from 2400 to 3500 mL/L, being highest for C. freundii H3 (3547 mL/L) and Enterobacter spH1 (3506 mL/L). The main nongaseous fermentation products were ethanol and acetate, albeit in different ratios. For Enterobacter spH1, Enterobacter spH2, C. freundii H3, and the mixture (1:1:1), the ethanol yields (in mol EtOH/mol glycerol consumed) were 0.96, 0.67, 0.31, and 0.66, respectively. Compared to the individual strains, the mixture (1:1:1) did not show a significantly higher hydrogen level, indicating that there was no synergistic effect. Enterobacter spH1 was selected for further investigation because of its higher yield of hydrogen and ethanol. Copyright © 2012 American Institute of Chemical Engineers (AIChE).

  18. Biohydrogen Production from Hydrolysates of Selected Tropical Biomass Wastes with Clostridium Butyricum

    Science.gov (United States)

    Dan Jiang; Fang, Zhen; Chin, Siew-Xian; Tian, Xiao-Fei; Su, Tong-Chao

    2016-06-01

    Biohydrogen production has received widespread attention from researchers in industry and academic fields. Response surface methodology (RSM) was applied to evaluate the effects of several key variables in anaerobic fermentation of glucose with Clostridium butyrium, and achieved the highest production rate and yield of hydrogen. Highest H2 yield of 2.02 mol H2/mol-glucose was achieved from 24 h bottle fermentation of glucose at 35 °C, while the composition of medium was (g/L): 15.66 glucose, 6.04 yeast extract, 4 tryptone, 3 K2HPO4, 3 KH2PO4, 0.05 L-cysteine, 0.05 MgSO4·7H2O, 0.1 MnSO4·H2O and 0.3 FeSO4·7H2O, which was very different from that for cell growth. Sugarcane bagasse and Jatropha hulls were selected as typical tropical biomass wastes to produce sugars via a two-step acid hydrolysis for hydrogen production. Under the optimized fermentation conditions, H2 yield (mol H2/mol-total reducing sugar) was 2.15 for glucose, 2.06 for bagasse hydrolysate and 1.95 for Jatropha hull hydrolysate in a 3L fermenter for 24 h at 35 °C, with H2 purity of 49.7-64.34%. The results provide useful information and basic data for practical use of tropical plant wastes to produce hydrogen.

  19. Bio-hydrogen production by dark fermentation from organic wastes and residues

    DEFF Research Database (Denmark)

    Liu, Dawei

    Der er stigende opmærksomhed omkring biohydrogen. Ved hydrogen fermentering kan kun en lille del af det organiske materiale eller COD i affald omdannes til hydrogen. Der findes endnu ingen full-skala bio-hydrogen anlæg, eftersom effektive rentable teknologier ikke er udviklet endnu. En to......-trins proces der kombinerer bio-hydrogen og bio-metan produktionen er en attraktiv mulighed til at øge det totale energi-udbytte af fermentering af organisk materiale. I en to-trins proces, med bio-hydrogen som første trin og bio-methan som andet trin, kunne der opnås 43mL-H2/gVSadded ved 37°C fra...... for en hurtig proces opstart og med højt brint effektivitet. Uden berigelseskulturer fejlede processen, på trods af gentagen genpodning. Optimale procesforhold for brint producerende processer blev bestemt. pH optimum af brintproducerende kulturer var 7.0 og acetat var hæmmende for brintproduktionen...

  20. Simultaneous Decolorization and Biohydrogen Production from Xylose by Klebsiella oxytoca GS-4-08 in the Presence of Azo Dyes with Sulfonate and Carboxyl Groups

    Science.gov (United States)

    Cao, Ming-yue; Wang, Peng-tao; Wang, Shi; Yue, Ying-rong; Yuan, Wen-duo; Qiao, Wei-chuan; Wang, Fei

    2017-01-01

    ABSTRACT Biohydrogen production from the pulp and paper effluent containing rich lignocellulosic material could be achieved by the fermentation process. Xylose, an important hemicellulose hydrolysis product, is used less efficiently as a substrate for biohydrogen production. Moreover, azo dyes are usually added to fabricate anticounterfeiting paper, which further increases the complexity of wastewater. This study reports that xylose could serve as the sole carbon source for a pure culture of Klebsiella oxytoca GS-4-08 to achieve simultaneous decolorization and biohydrogen production. With 2 g liter−1 of xylose as the substrate, a maximum xylose utilization rate (URxyl) and a hydrogen molar yield (HMY) of 93.99% and 0.259 mol of H2 mol of xylose−1, respectively, were obtained. Biohydrogen kinetics and electron equivalent (e− equiv) balance calculations indicated that methyl red (MR) penetrates and intracellularly inhibits both the pentose phosphate pathway and pyruvate fermentation pathway, while methyl orange (MO) acted independently of the glycolysis and biohydrogen pathway. The data demonstrate that biohydrogen pathways in the presence of azo dyes with sulfonate and carboxyl groups were different, but the azo dyes could be completely reduced during the biohydrogen production period in the presence of MO or MR. The feasibility of hydrogen production from industrial pulp and paper effluent by the strain if the xylose is sufficient was also proved and was not affected by toxic substances which usually exist in such wastewater, except for chlorophenol. This study offers a promising energy-recycling strategy for treating pulp and paper wastewaters, especially for those containing azo dyes. IMPORTANCE The pulp and paper industry is a major industry in many developing countries, and the global market of pulp and paper wastewater treatment is expected to increase by 60% between 2012 and 2020. Such wastewater contains large amounts of refractory contaminants, such

  1. A farm-scale pilot plant for biohydrogen and biomethane production by two-stage fermentation

    Directory of Open Access Journals (Sweden)

    R. Oberti

    2013-09-01

    laboratory results, with a typical hydrogen and methane specific productivity of 2.2 and 0.5 Nm3/m3reactor per day, in the first and second stage of the plant respectively. At our best knowledge, this plant is one of the very first prototypes producing biohydrogen at farm scale, and it represents a distributed, small scale demonstration to obtain hydrogen from renewable waste-sources.

  2. An integrated green process: Subcritical water, enzymatic hydrolysis, and fermentation, for biohydrogen production from coconut husk.

    Science.gov (United States)

    Muharja, Maktum; Junianti, Fitri; Ranggina, Dian; Nurtono, Tantular; Widjaja, Arief

    2018-02-01

    The objective of this work is to develop an integrated green process of subcritical water (SCW), enzymatic hydrolysis and fermentation of coconut husk (CCH) to biohydrogen. The maximum sugar yield was obtained at mild severity factor. This was confirmed by the degradation of hemicellulose, cellulose and lignin. The tendency of the changing of sugar yield as a result of increasing severity factor was opposite to the tendency of pH change. It was found that CO 2 gave a different tendency of severity factor compared to N 2 as the pressurizing gas. The result of SEM analysis confirmed the structural changes during SCW pretreatment. This study integrated three steps all of which are green processes which ensured an environmentally friendly process to produce a clean biohydrogen. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Effect of total solids content on biohydrogen production and lactic acid accumulation during dark fermentation of organic waste biomass.

    Science.gov (United States)

    Ghimire, Anish; Trably, Eric; Frunzo, Luigi; Pirozzi, Francesco; Lens, Piet N L; Esposito, Giovanni; Cazier, Elisabeth A; Escudié, Renaud

    2018-01-01

    Production of biohydrogen and related metabolic by-products was investigated in Solid State Dark Fermentation (SSDF) of food waste (FW) and wheat straw (WS). The effect of the total solids (TS) content and H 2 partial pressure (pp H2 ), two of the main operating factors of SSDF, were investigated. Batch tests with FW at 10, 15, 20, 25 and 30% TS showed considerable effects of the TS on metabolites distribution. H 2 production was strongly inhibited for TS contents higher than 15% with a concomitant accumulation of lactic acid and a decrease in substrate conversion. Varying the pp H2 had no significant effect on the conversion products and overall degradation of FW and WS, suggesting that pp H2 was not the main limiting factor in SSDF. This study showed that the conversion of complex substrates by SSDF depends on the substrate type and is limited by the TS content. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Biohydrogen production from pig slurry in a CSTR reactor system with mixed cultures under hyper-thermophilic temperature (70 oC)

    International Nuclear Information System (INIS)

    Kotsopoulos, Thomas A.; Fotidis, Ioannis A.; Tsolakis, Nikolaos; Martzopoulos, Gerassimos G.

    2009-01-01

    A continuous stirred tank reactor (CSTR) (750 cm 3 working volume) was operated with pig slurry under hyper-thermophilic (70 o C) temperature for hydrogen production. The hydraulic retention time (HRT) was 24 h and the organic loading rate was 24.9 g d -1 of volatile solid (VS). The inoculum used in the hyper-thermophilic reactor was sludge obtained from a mesophilic methanogenic reactor. The continuous feeding with active biomass (inoculum) from the mesophilic methanogenic reactor was necessary in order to achieve hydrogen production. The hyper-thermophilic reactor started to produce hydrogen after a short adapted period of 4 days. During the steady state period the mean hydrogen yield was 3.65 cm 3 g -1 of volatile solid added. The high operation temperature of the reactor enhanced the hydrolytic activity in pig slurry and increased the volatile fatty acids (VFA) production. The short HRT (24 h) and the hyper-thermophilic temperature applied in the reactor were enough to prevent methanogenesis. No pre-treatment methods or other control methods for preventing methanogenesis were necessary. Hyper-thermophilic hydrogen production was demonstrated for the first time in a CSTR system, fed with pig slurry, using mixed culture. The results indicate that this system is a promising one for biohydrogen production from pig slurry.

  5. Biohydrogen production from glucose in upflow biofilm reactors with plastic carriers under extreme thermophilic conditions (70(degree)C)

    DEFF Research Database (Denmark)

    Zheng, H.; Zeng, Raymond Jianxiong; Angelidaki, Irini

    2008-01-01

    Biohydrogen could efficiently be produced in glucose-fed biofilm reactors filled with plastic carriers and operated at 70°C. Batch experiments were, in addition, conducted to enrich and cultivate glucose-fed extremethermophilic hydrogen producing microorganisms from a biohydrogen CSTR reactor fed...

  6. Fermentative biohydrogen and biomethane co-production from mixture of food waste and sewage sludge: Effects of physiochemical properties and mix ratios on fermentation performance

    International Nuclear Information System (INIS)

    Cheng, Jun; Ding, Lingkan; Lin, Richen; Yue, Liangchen; Liu, Jianzhong; Zhou, Junhu; Cen, Kefa

    2016-01-01

    Highlights: • Microanalyses revealed food waste had more gelatinized organics and less mineral ash. • Mixed food waste and sewage sludge at 5 ratios were used for H_2 and CH_4 co-production. • Highest H_2 yield of 174.6 mL/gVS was achieved when food waste:sewage sludge was 3:1. • Co-fermentation enhanced carbon conversion by strengthening hydrolysis of substrates. • Energy yield rose from 1.9 kJ/gVS in H_2 to 11.3 kJ/gVS in H_2 and CH_4 co-production. - Abstract: The accumulation of increasingly generated food waste and sewage sludge is currently a heavy burden on environment in China. In this study, the physiochemical properties of food waste and sewage sludge were identified using scanning electron microscopy and Fourier transform infrared spectroscopy to investigate the effects on the fermentation performance in the co-fermentation of food waste and sewage sludge for biohydrogen production. The high gelatinized organic components in food waste, the enhanced bioaccessibility due to the dilution of mineral compounds in sewage sludge, and the balanced C/N ratio synergistically improved the fermentative biohydrogen production through the co-fermentation of food waste and sewage sludge at a volatile solids (VS) mix ratio of 3:1. The biohydrogen yield of 174.6 mL/gVS was 49.9% higher than the weighted average calculated from mono-fermentation of food waste and sewage sludge. Co-fermentation also strengthened the hydrolysis and acidogenesis of the mixture, resulting in a total carbon conversion efficiency of 63.3% and an energy conversion efficiency of 56.6% during biohydrogen production. After the second-stage anaerobic digestion of hydrogenogenic effluent, the energy yield from the mixed food waste and sewage sludge significantly increased from 1.9 kJ/gVS in the first-stage biohydrogen production to 11.3 kJ/gVS in the two-stage fermentative biohydrogen and biomethane co-production.

  7. Production of bio-hydrogenated diesel by catalytic hydrotreating of palm oil over NiMoS2/γ-Al2O3 catalyst.

    Science.gov (United States)

    Srifa, Atthapon; Faungnawakij, Kajornsak; Itthibenchapong, Vorranutch; Viriya-Empikul, Nawin; Charinpanitkul, Tawatchai; Assabumrungrat, Suttichai

    2014-04-01

    Catalytic hydrotreating of palm oil (refined palm olein type) to produce bio-hydrogenated diesel (BHD) was carried out in a continuous-flow fixed-bed reactor over NiMoS2/γ-Al2O3 catalyst. Effects of dominant hydrotreating parameters: temperature: 270-420°C; H2 pressure: 15-80 bar; LHSV: 0.25-5.0 h(-1); and H2/oil ratio: 250-2000 N(cm(3)/cm(3)) on the conversion, product yield, and a contribution of hydrodeoxygenation (HDO) and decarbonylation/decarboxylation (DCO/DCO2) were investigated to find the optimal hydrotreating conditions. All calculations including product yield and the contribution of HDO and DCO/DCO2 were extremely estimated based on mole balance corresponding to the fatty acid composition in feed to fully understand deoxygenation behaviors at different conditions. These analyses demonstrated that HDO, DCO, and DCO2 reactions competitively occurred at each condition, and had different optimal and limiting conditions. The differences in the hydrotreating reactions, liquid product compositions, and gas product composition were also discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Survey on the possibility of international cooperation on production technology of biohydrogen; Bio suiso seizo gijutsu ni kakawaru kokusai kyoryoku kanosei chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    R and D on the production technology of hydrogen by biotechnology is one of the effective projects for worldwide energy supply technology and global environment protection technology in the 21st century. The research trend of various institutions promoting R and D on production technology of biohydrogen in the U.S.A. and other countries was surveyed together with the possibility of international cooperation. The production technology of biohydrogen is being watched over the world. Various researches are in promotion corresponding to environmental conditions as follows: search of not only photosynthetic bacteria but also such bacteria with hydrogen productivity as algae and anaerobic bacteria, and the gene engineering study for improving the hydrogen productivity of target microorganisms. All the institutions visited for this survey have great expectations in wide cooperative study in the future. On the possibility of international cooperation on the production technology of biohydrogen, the further precise survey should be promoted for developing more effective technologies based on the previous survey results. 156 refs., 10 tabs.

  9. Improved production of biohydrogen in light-powered Escherichia coli by co-expression of proteorhodopsin and heterologous hydrogenase

    Directory of Open Access Journals (Sweden)

    Kim Jaoon YH

    2012-01-01

    Full Text Available Abstract Background Solar energy is the ultimate energy source on the Earth. The conversion of solar energy into fuels and energy sources can be an ideal solution to address energy problems. The recent discovery of proteorhodopsin in uncultured marine γ-proteobacteria has made it possible to construct recombinant Escherichia coli with the function of light-driven proton pumps. Protons that translocate across membranes by proteorhodopsin generate a proton motive force for ATP synthesis by ATPase. Excess protons can also be substrates for hydrogen (H2 production by hydrogenase in the periplasmic space. In the present work, we investigated the effect of the co-expression of proteorhodopsin and hydrogenase on H2 production yield under light conditions. Results Recombinant E. coli BL21(DE3 co-expressing proteorhodopsin and [NiFe]-hydrogenase from Hydrogenovibrio marinus produced ~1.3-fold more H2 in the presence of exogenous retinal than in the absence of retinal under light conditions (70 μmole photon/(m2·s. We also observed the synergistic effect of proteorhodopsin with endogenous retinal on H2 production (~1.3-fold more with a dual plasmid system compared to the strain with a single plasmid for the sole expression of hydrogenase. The increase of light intensity from 70 to 130 μmole photon/(m2·s led to an increase (~1.8-fold in H2 production from 287.3 to 525.7 mL H2/L-culture in the culture of recombinant E. coli co-expressing hydrogenase and proteorhodopsin in conjunction with endogenous retinal. The conversion efficiency of light energy to H2 achieved in this study was ~3.4%. Conclusion Here, we report for the first time the potential application of proteorhodopsin for the production of biohydrogen, a promising alternative fuel. We showed that H2 production was enhanced by the co-expression of proteorhodopsin and [NiFe]-hydrogenase in recombinant E. coli BL21(DE3 in a light intensity-dependent manner. These results demonstrate that E. coli

  10. Evaluation and simultaneous optimization of bio-hydrogen production using 3 2 factorial design and the desirability function

    Science.gov (United States)

    Cuetos, M. J.; Gómez, X.; Escapa, A.; Morán, A.

    Various mixtures incorporating a simulated organic fraction of municipal solid wastes and blood from a poultry slaughterhouse were used as substrate in a dark fermentation process for the production of hydrogen. The individual and interactive effects of hydraulic retention time (HRT), solid content in the feed (%TS) and proportion of residues (%Blood) on bio-hydrogen production were studied in this work. A central composite design and response surface methodology were employed to determine the optimum conditions for the hydrogen production process. Experimental results were approximated to a second-order model with the principal effects of the three factors considered being statistically significant (P < 0.05). The production of hydrogen obtained from the experimental point at conditions close to best operability was 0.97 L Lr -1 day -1. Moreover, a desirability function was employed in order to optimize the process when a second, methanogenic, phase is coupled with it. In this last case, the optimum conditions lead to a reduction in the production of hydrogen when the optimization process involves the maximization of intermediary products.

  11. Effect of Inlet Velocity on Heat Transfer Process in a Novel Photo-Fermentation Biohydrogen Production Bioreactor using Computational Fluid Dynamics Simulation

    Directory of Open Access Journals (Sweden)

    Zhiping Zhang

    2014-11-01

    Full Text Available Temperature is one of the most important parameters in biohydrogen production by way of photo-fermentation. Enzymatic hydrolysate of corncob powder was utilized as a substrate. Computational fluid dynamics (CFD modeling was conducted to simulate the temperature distribution in an up-flow baffle photo-bioreactor (UBPB. Commercial software, GAMBIT, was utilized to mesh the photobioreactor geometry, while the software FLUENT was adopted to simulate the heat transfer in the photo-fermentation process. The inlet velocity had a marked impact on heat transfer; the most optimum velocity value was 0.0036 m•s-1 because it had the smallest temperature fluctuation and the most uniform temperature distribution. When the velocity decreased from 0.0036 m•s-1 to 0.0009 m•s-1, more heat was accumulated. The results obtained from the established model were consistent to the actual situation by comparing the simulation values and experimental values. The hydrogen production simulation verified that the novel UBPB was suitable for biohydrogen production by photosynthetic bacteria because of its uniform temperature and lighting distribution, with the serpentine flow pattern also providing mixing without additional energy input, thus enhancing the mass transfer and biohydrogen yield.

  12. High efficiency bio-hydrogen production from glucose revealed in an inoculum of heat-pretreated landfill leachate sludge

    International Nuclear Information System (INIS)

    Wong, Y.M.; Juan, J.C.; Ting, Adeline; Wu, T.Y.

    2014-01-01

    Bio-hydrogen is a promising sustainable energy to replace fossil fuels. This study investigated bio-H 2 production from the inoculum of heat-pretreated landfill leachate sludge using glucose as model substrate. The seed sludge pretreated at 65 °C showed the highest amount of H 2 at the optimum condition of pH 6 and 37 °C. The maximum H 2 yield estimated by the modified Gompertz model was 6.43 mol H 2 /mol glucose. The high efficient of H 2 production is thermodynamically feasible with the Gibbs free energy of −34 kJ/mol. This study reveals that pretreated landfill leachate sludge has considerable potential for H 2 production. - Highlights: • Heat retreated landfill leachate sludge revealed high efficient H 2 production. • High efficient H 2 yield, 6.4 mol H 2 /mol glucose. • The synergisms between H 2 -producing bacteria may responsible for the high H 2 yield. • High H 2 yield is thermodynamically feasible with Gibbs free energy of −34 kJ/mol

  13. Optimization studies of bio-hydrogen production in a coupled microbial electrolysis-dye sensitized solar cell system.

    Science.gov (United States)

    Ajayi, Folusho Francis; Kim, Kyoung-Yeol; Chae, Kyu-Jung; Choi, Mi-Jin; Chang, In Seop; Kim, In S

    2010-03-01

    Bio-hydrogen production in light-assisted microbial electrolysis cell (MEC) with a dye sensitized solar cell (DSSC) was optimized by connecting multiple MECs to a single dye (N719) sensitized solar cell (V(OC) approx. 0.7 V). Hydrogen production occurred simultaneously in all the connected MECs when the solar cell was irradiated with light. The amount of hydrogen produced in each MEC depends on the activity of the microbial catalyst on their anode. Substrate (acetate) to hydrogen conversion efficiencies ranging from 42% to 65% were obtained from the reactors during the experiment. A moderate light intensity of 430 W m(-2) was sufficient for hydrogen production in the coupled MEC-DSSC. A higher light intensity of 915 W m(-2), as well as an increase in substrate concentration, did not show any improvement in the current density due to limitation caused by the rate of microbial oxidation on the anode. A significant reduction in the surface area of the connected DSSC only showed a slight effect on current density in the coupled MEC-DSSC system when irradiated with light.

  14. Enhanced Bio-hydrogen Production from Protein Wastewater by Altering Protein Structure and Amino Acids Acidification Type

    Science.gov (United States)

    Xiao, Naidong; Chen, Yinguang; Chen, Aihui; Feng, Leiyu

    2014-01-01

    Enhanced bio-hydrogen production from protein wastewater by altering protein structure and amino acids acidification type via pH control was investigated. The hydrogen production reached 205.2 mL/g-protein when protein wastewater was pretreated at pH 12 and then fermented at pH 10. The mechanism studies showed that pH 12 pretreatment significantly enhanced protein bio-hydrolysis during the subsequent fermentation stage as it caused the unfolding of protein, damaged the protein hydrogen bonding networks, and destroyed the disulfide bridges, which increased the susceptibility of protein to protease. Moreover, pH 10 fermentation produced more acetic but less propionic acid during the anaerobic fermentation of amino acids, which was consistent with the theory of fermentation type affecting hydrogen production. Further analyses of the critical enzymes, genes, and microorganisms indicated that the activity and abundance of hydrogen producing bacteria in the pH 10 fermentation reactor were greater than those in the control. PMID:24495932

  15. Enhanced bio-hydrogen production from protein wastewater by altering protein structure and amino acids acidification type.

    Science.gov (United States)

    Xiao, Naidong; Chen, Yinguang; Chen, Aihui; Feng, Leiyu

    2014-02-05

    Enhanced bio-hydrogen production from protein wastewater by altering protein structure and amino acids acidification type via pH control was investigated. The hydrogen production reached 205.2 mL/g-protein when protein wastewater was pretreated at pH 12 and then fermented at pH 10. The mechanism studies showed that pH 12 pretreatment significantly enhanced protein bio-hydrolysis during the subsequent fermentation stage as it caused the unfolding of protein, damaged the protein hydrogen bonding networks, and destroyed the disulfide bridges, which increased the susceptibility of protein to protease. Moreover, pH 10 fermentation produced more acetic but less propionic acid during the anaerobic fermentation of amino acids, which was consistent with the theory of fermentation type affecting hydrogen production. Further analyses of the critical enzymes, genes, and microorganisms indicated that the activity and abundance of hydrogen producing bacteria in the pH 10 fermentation reactor were greater than those in the control.

  16. Simultaneous biohydrogen production and starch wastewater treatment in an acidogenic expanded granular sludge bed reactor by mixed culture for long-term operation

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Wan-Qian; Ren, Nan-Qi; Liu, Bing-Feng; Ding, Jie [State Key Lab of Urban Water Resource and Environ, Harbin Institute of Technology, Harbin 150090 (China); Chen, Zhao-Bo [School of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); Wang, Xiang-Jing; Xiang, Wen-Sheng [Research Center of Life Science and Biotechnology, Northeast Agricultural University, Harbin 150030 (China)

    2008-12-15

    The biofilm-based expanded granular sludge bed (EGSB) reactor was developed to treat starch-containing wastewater and simultaneously recovery hydrogen by mixed microbial culture. Granular activated carbon (GAC) was used as the support media. Operating at the temperature of 30 C for over 400 days (data not shown), the EGSB reactor presented high efficiency in hydrogen production and COD removal ability. The maximum hydrogen production rate (HPR) was found to be 1.64 L/L.d under the organic loading rate (OLR) of 1.0 g-starch/L.d, pH of 4.42 and HRT of 4 h. The hydrogen yield (HY) peaked at 0.11 L/g-COD, under the OLR of 0.5 g-starch/L.d, pH of 3.95 and HRT of 8 h. Hydrogen volume content was estimated to be 35-65% of the total biogas. The average COD removal rate was 31.1% under the OLR of 0.125 g-starch/L.d and HRT of 24 h. The main dissolved fermentation products were ethanol, acetate and butyrate. The average attached biofilm concentration was estimated to be 8.26 g/L, which favored hydrogen production and COD removal. It is speculated that the low pH operation in the present system would contribute significantly to lower the cost of alkaline amount required for pH control in the continuous operation, especially in the scale-up biohydrogen producing system. A model, built on the back propagation neural network (BPNN) theory and linear regression techniques, was developed for the simulation of EGSB system performance in the biodegradation of starch synthesis-based wastewater and simultaneous hydrogen production. The model well fitted the laboratory data, and could well simulate the removal of COD and the production of hydrogen in the EGSB reactor. (author)

  17. Studies on bio-hydrogen production of different biomass fermentation types using molasses wastewater as substrate

    Energy Technology Data Exchange (ETDEWEB)

    Liu, K.; Jiao, A.Y.; Rao, P.H. [Northeast Forestry Univ., Harbin (China). School of Forestry; Li, Y.F. [Northeast Forestry Univ., Harbin (China). School of Forestry; Shanghai Univ. Engineering, Shanghai (China). College of Chemistry and Chemical Engineering; Li, W. [Beijing Normal Univ., Beijing (China)

    2010-07-01

    Anaerobic fermentation technology was used to treat molasses wastewater. This study compared the hydrogen production capability of different fermentation types involving dark fermentation hydrogen production. The paper discussed the experiment including the results. It was found that the fermentation type changed by changing engineered control parameters in a continuous stirred tank reactor (CSTR). It was concluded that ethanol-type fermentation resulted in the largest hydrogen production capability, while butyric acid-type fermentation took second place followed by propionic acid-type fermentation.

  18. Organic loading rate impact on biohydrogen production and microbial communities at anaerobic fluidized thermophilic bed reactors treating sugarcane stillage.

    Science.gov (United States)

    Santos, Samantha Christine; Rosa, Paula Rúbia Ferreira; Sakamoto, Isabel Kimiko; Varesche, Maria Bernadete Amâncio; Silva, Edson Luiz

    2014-05-01

    This study aimed to evaluate the effect of high organic loading rates (OLR) (60.0-480.00 kg COD m(-3)d(-1)) on biohydrogen production at 55°C, from sugarcane stillage for 15,000 and 20,000 mg CODL(-1), in two anaerobic fluidized bed reactors (AFBR1 and AFBR2). It was obtained, for H2 yield and content, a decreasing trend by increasing the OLR. The maximum H2 yield was observed in AFBR1 (2.23 mmol g COD added(-1)). The volumetric H2 production was proportionally related to the applied hydraulic retention time (HRT) of 6, 4, 2 and 1h and verified in AFBR1 the highest value (1.49 L H2 h(-1)L(-1)). Among the organic acids obtained, there was a predominance of lactic acid (7.5-22.5%) and butyric acid (9.4-23.8%). The microbial population was set with hydrogen-producing fermenters (Megasphaera sp.) and other organisms (Lactobacillus sp.). Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Syntrophic co-culture of aerobic Bacillus and anaerobic Clostridium for bio-fuels and bio-hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jui-Jen; Ho, Cheng-Yu.; Chen, Wei-En; Huang, Chieh-Chen [Department of Life Sciences, National Chung Hsing University, Taichung (China); Chou, Chia-Hung; Lay, Jiunn-Jyi [Department of Science and Technology, National Kaohsiung First University, Kaohsiung (China)

    2008-10-15

    By using brewery yeast waste and microflora from rice straw compost, an anaerobic semi-solid bio-hydrogen-producing system has been established. For the purpose of industrialization, the major players of both aerobic and anaerobic bacterial strains in the system were isolated and their combination for an effective production of bio-hydrogen and other bio-fuels was examined in this study. The phylogenetic analysis found that four anaerobic isolates (Clostridium beijerinckii L9, Clostridium diolis Z2, Clostridium roseum Z5-1, and C. roseum W8) were highly related with each other and belongs to the cluster I clostridia family, the family that many of solvent-producing strains included. On the other hand, one of the aerobic isolates, the Bacillus thermoamylovorans strain I, shown multiple extracellular enzyme activities including lipase, protease, {alpha}-amylase, pectinase and cellulase, was suggested as a good partner for creating an anaerobic environment and pre-saccharification of substrate for those co-cultured solventogenic clostridial strain. Among these clostridial strains, though C. beijerinckii L9 do not show as many extracellular enzyme activities as Bacillus, but it performs the highest hydrogen-producing ability. The original microflora can be updated to a syntrophic bacterial co-culture system contended only with B. thermoamylovorans I and C. beijerinckii L9. The combination of aerobic Bacillus and anaerobic Clostridium may play the key role for developing the industrialized bio-fuels and bio-hydrogen-producing system from biomass. (author)

  20. Biohydrogen production from household solid waste (HSW) at extreme-thermophilic temperature (70 degrees C) - Influence of pH and acetate concentration

    DEFF Research Database (Denmark)

    Liu, Dawei; Min, Booki; Angelidaki, Irini

    2008-01-01

    Hydrogen production from household solid waste (HSW) was performed via dark fermentation by using an extreme-thermophilic mixed culture, and the effect of pH and acetate on the biohydrogen production was investigated. The highest hydrogen production yield was 257 +/- 25 mL/gVS(added) at the optimum...... pH of 7.0. Acetate was proved to be inhibiting the dark fermentation process at neutral pH, which indicates that the inhibition was caused by total acetate concentration not by undissociated acetate. Initial inhibition was detected at acetate concentration of 50 mM, while the hydrogen fermentation...

  1. Simultaneous Biohydrogen and Bioethanol Production from Anaerobic Fermentation with Immobilized Sludge

    Science.gov (United States)

    Han, Wei; Wang, Zhanqing; Chen, Hong; Yao, Xin; Li, Yongfeng

    2011-01-01

    The effects of organic loading rates (OLRs) on fermentative productions of hydrogen and ethanol were investigated in a continuous stirred tank reactor (CSTR) with attached sludge using molasses as substrate. The CSTR reactor with attached sludge was operated under different OLRs, ranging from 8 to 24 kg/m3·d. The H2 and ethanol production rate essentially increased with increasing OLR. The highest H2 production rate (10.74 mmol/h·L) and ethanol production rate (11.72 mmol/h·L) were obtained both operating at OLR = 24 kg/m3·d. Linear regression results show that ethanol production rate (y) and H2 production rate (x) were proportionately correlated and can be expressed as y = 1.5365x − 5.054 (r2 = 0.9751). The best energy generation rate was 19.08 kJ/h·L, which occurred at OLR = 24 kg/m3·d. In addition, the hydrogen yield was affected by the presence of ethanol and acetic acid in the liquid phase, and the maximum hydrogen production rate occurred while the ratio of ethanol to acetic acid was close to 1. PMID:21799660

  2. Simultaneous Biohydrogen and Bioethanol Production from Anaerobic Fermentation with Immobilized Sludge

    Directory of Open Access Journals (Sweden)

    Wei Han

    2011-01-01

    Full Text Available The effects of organic loading rates (OLRs on fermentative productions of hydrogen and ethanol were investigated in a continuous stirred tank reactor (CSTR with attached sludge using molasses as substrate. The CSTR reactor with attached sludge was operated under different OLRs, ranging from 8 to 24 kg/m3·d. The H2 and ethanol production rate essentially increased with increasing OLR. The highest H2 production rate (10.74 mmol/h⋅L and ethanol production rate (11.72 mmol/h⋅L were obtained both operating at OLR = 24 kg/m3·d. Linear regression results show that ethanol production rate ( and H2 production rate ( were proportionately correlated and can be expressed as =1.5365−5.054 (2=0.9751. The best energy generation rate was 19.08 kJ/h⋅L, which occurred at OLR = 24 kg/m3·d. In addition, the hydrogen yield was affected by the presence of ethanol and acetic acid in the liquid phase, and the maximum hydrogen production rate occurred while the ratio of ethanol to acetic acid was close to 1.

  3. Enhanced biohydrogen production by the N{sub 2}-fixing cyanobacterium Anabaena siamensis strain TISTR 8012

    Energy Technology Data Exchange (ETDEWEB)

    Khetkorn, Wanthanee [Program of Biotechnology, Faculty of Science, Chulalongkorn University, Bangkok, 10330 (Thailand); Laboratory of Cyanobacterial Biotechnology, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Bangkok, 10330 (Thailand); Department of Photochemistry and Molecular Science, Uppsala University, Box 523, SE-75120, Uppsala (Sweden); Lindblad, Peter [Department of Photochemistry and Molecular Science, Uppsala University, Box 523, SE-75120, Uppsala (Sweden); Incharoensakdi, Aran [Laboratory of Cyanobacterial Biotechnology, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Bangkok, 10330 (Thailand)

    2010-12-15

    The efficiency of hydrogen production depends on several factors. We focused on external conditions leading to enhanced hydrogen production when using the N{sub 2}-fixing cyanobacterium Anabaena siamensis TISTR 8012, a novel strain isolated from a rice paddy field in Thailand. In this study, we controlled key factors affecting hydrogen production such as cell age, light intensity, time of light incubation and source of carbon. Our results showed an enhanced hydrogen production when cells, at log phase, were adapted under N{sub 2}-fixing condition using 0.5% fructose as carbon source and a continuous illumination of 200 {mu}E m{sup -2} s{sup -1} for 12 h under anaerobic incubation. The maximum hydrogen production rate was 32 {mu}mol H{sub 2} mg chl a{sup -1} h{sup -1}. This rate was higher than that observed in the model organisms Anabaena PCC 7120, Nostoc punctiforme ATCC 29133 and Synechocystis PCC 6803. This higher production was likely caused by a higher nitrogenase activity since we observed an upregulation of nifD. The production did not increase after 12 h which was probably due to an increased activity of the uptake hydrogenase as evidenced by an increased hupL transcript level. Interestingly, a proper adjustment of light conditions such as intensity and duration is important to minimize both the photodamage of the cells and the uptake hydrogenase activity. Our results indicate that A. siamensis TISTR 8012 has a high potential for hydrogen production with the ability to utilize sugars as substrate to produce hydrogen. (author)

  4. Biohydrogen production from purified terephthalic acid (PTA) processing wastewater by anaerobic fermentation using mixed microbial communities

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Ge-Fu; Wu, Peng; Wei, Qun-Shan; Lin, Jian-yi; Liu, Hai-Ning [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Gao, Yan-Li [China University of Geosciences, Wuhan 430074 (China)

    2010-08-15

    Purified terephthalic acid (PTA) processing wastewater was evaluated as a fermentable substrate for hydrogen (H{sub 2}) production with simultaneous wastewater treatment by dark-fermentation process in a continuous stirred-tank reactor (CSTR) with selectively enriched acidogenic mixed consortia under continuous flow condition in this paper. The inoculated sludge used in the reactor was excess sludge taken from a second settling tank in a local wastewater treatment plant. Under the conditions of the inoculants not less than 6.3 gVSS/L, the organic loading rate (OLR) of 16 kgCOD/m{sup 3} d, hydraulic retention time (HRT) of 6 h and temperature of (35 {+-} 1) C, when the pH value, alkalinity and oxidation-reduction potential (ORP) of the effluent ranged from 4.2 to 4.4, 280 to 350 mg CaCO{sub 3}/L, and -220 to -250 mV respectively, soluble metabolites were predominated by acetate and ethanol, with smaller quantities of propionate, butyrate and valerate. Stable ethanol-type fermentation was formed with the sum of ethanol and acetate concentration ratio of 70.31% to the total liquid products after 25 days operation. The H{sub 2} volume content was estimated to be 48-53% of the total biogas and the biogas was free of methane throughout the study. The average biomass concentration was estimated to be 10.82 gVSS/L, which favored H{sub 2} production efficiently. The rate of chemical oxygen demand (COD) removal reached at about 45% and a specific H{sub 2} production rate achieved 0.073 L/gMLVSS d in the study. This CSTR system showed a promising high-efficient bioprocess for H{sub 2} production from high-strength chemical wastewater. (author)

  5. 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)

  6. Development of a combined bio-hydrogen- and methane-production unit using dark fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Brunstermann, R.; Widmann, R. [Duisburg-Essen Univ. (Germany). Dept. of Urban Water and Waste Management

    2010-07-01

    Hydrogen is regarded as a source of energy of the future. Currently, hydrogen is produced, predominantly, by electrolysis of water by using electricity or by stream reforming of natural gas. So both methods are based on fossil fuels. If the used electricity is recovered from renewable recourses, hydrogen produced by water electrolysis may be a clean solution. At present, the production of hydrogen by biological processes finds more and more attention world far. The biology provides a wide range of approaches to produce hydrogen, including bio-photolysis as well as photo-fermentation and dark-fermentation. Currently these biological technologies are not suitable for solving every day energy problems [1]. But the dark-fermentation is a promising approach to produce hydrogen in a sustainable way and was already examined in some projects. At mesophilic conditions this process provides a high yield of hydrogen by less energy demand, [2]. Short hydraulic retention times (HRT) and high metabolic rates are advantages of the process. The incomplete transformation of the organic components into various organic acids is a disadvantage. Thus a second process step is required. Therefore the well known biogas-technique is used to degrade the organic acids predominantly acetic and butyric acid from the hydrogen-production unit into CH{sub 4} and CO{sub 2}. This paper deals with the development of a combined hydrogen and methane production unit using dark fermentation at mesophilic conditions. The continuous operation of the combined hydrogen and methane production out of DOC loaded sewages and carbohydrate rich biowaste is necessary for the examination of the technical and economical implementation. The hydrogen step shows as first results hydrogen concentration in the biogas between 40 % and 60 %.The operating efficiency of the combined production of hydrogen and methane shall be checked as a complete system. (orig.)

  7. Fatty acid oxidation products ('green odour') released from perennial ryegrass following biotic and abiotic stress, potentially have antimicrobial properties against the rumen microbiota resulting in decreased biohydrogenation.

    Science.gov (United States)

    Huws, S A; Scott, M B; Tweed, J K S; Lee, M R F

    2013-11-01

    In this experiment, we investigated the effect of 'green odour' products typical of those released from fresh forage postabiotic and biotic stresses on the rumen microbiota and lipid metabolism. Hydroperoxyoctadecatrienoic acid (HP), a combination of salicylic and jasmonic acid (T), and a combination of both (HPT) were incubated in vitro in the presence of freeze-dried ground silage and rumen fluid, under rumen-like conditions. 16S rRNA (16S cDNA) HaeIII-based terminal restriction fragment length polymorphism-based (T-RFLP) dendrograms, canonical analysis of principal coordinates graphs, peak number and Shanon-Weiner diversity indices show that HP, T and HPT likely had antimicrobial effects on the microbiota compared to control incubations. Following 6 h of in vitro incubation, 15.3% of 18:3n-3 and 4.4% of 18:2n-6 was biohydrogenated in control incubations, compared with 1.3, 9.4 and 8.3% of 18:3n-3 for HP, T and HPT treatments, respectively, with negligible 18:2n-6 biohydrogenation seen. T-RFLP peaks lost due to application of HP, T and HPT likely belonged to as yet uncultured bacteria within numerous genera. Hydroperoxyoctadecatrienoic acid, T and HPT released due to plant stress potentially have an antimicrobial effect on the rumen microbiota, which may explain the decreased biohydrogenation in vitro. These data suggest that these volatile chemicals may be responsible for the higher summer n-3 content of bovine milk. © 2013 The Society for Applied Microbiology.

  8. Bio-hydrogen production based on catalytic reforming of volatiles generated by cellulose pyrolysis: An integrated process for ZnO reduction and zinc nanostructures fabrication

    International Nuclear Information System (INIS)

    Maciel, Adriana Veloso; Job, Aldo Eloizo; Nova Mussel, Wagner da; Brito, Walter de; Duarte Pasa, Vanya Marcia

    2011-01-01

    The paper presents a process of cellulose thermal degradation with bio-hydrogen generation and zinc nanostructures synthesis. Production of zinc nanowires and zinc nanoflowers was performed by a novel processes based on cellulose pyrolysis, volatiles reforming and direct reduction of ZnO. The bio-hydrogen generated in situ promoted the ZnO reduction with Zn nanostructures formation by vapor-solid (VS) route. The cellulose and cellulose/ZnO samples were characterized by thermal analyses (TG/DTG/DTA) and the gases evolved were analyzed by FTIR spectroscopy (TG/FTIR). The hydrogen was detected by TPR (Temperature Programmed Reaction) tests. The results showed that in the presence of ZnO the cellulose thermal degradation produced larger amounts of H 2 when compared to pure cellulose. The process was also carried out in a tubular furnace with N 2 atmosphere, at temperatures up to 900 o C, and different heating rates. The nanostructures growth was catalyst-free, without pressure reduction, at temperatures lower than those required in the carbothermal reduction of ZnO with fossil carbon. The nanostructures were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). The optical properties were investigated by photoluminescence (PL). One mechanism was presented in an attempt to explain the synthesis of zinc nanostructures that are crystalline, were obtained without significant re-oxidation and whose morphologies are dependent on the heating rates of the process. This route presents a potential use as an industrial process taking into account the simple operational conditions, the low costs of cellulose and the importance of bio-hydrogen and nanostructured zinc.

  9. Improved cellulose conversion to bio-hydrogen with thermophilic bacteria and characterization of microbial community in continuous bioreactor

    International Nuclear Information System (INIS)

    Jiang, Hongyu; Gadow, Samir I.; Tanaka, Yasumitsu; Cheng, Jun; Li, Yu-You

    2015-01-01

    Thermophilic hydrogen fermentation of cellulose was evaluated by a long term continuous experiment and batch experiments. The continuous experiment was conducted under 55 °C using a continuously stirred tank reactor (CSTR) at a hydraulic retention time (HRT) of 10 day. A stable hydrogen yield of 15.4 ± 0.23 mol kg −1 of cellulose consumed was maintained for 190 days with acetate and butyrate as the main soluble byproducts. An analysis of the 16S rRNA sequences showed that the hydrogen-producing thermophilic cellulolytic microorganisms (HPTCM) were close to Thermoanaerobacterium thermosaccharolyticum, Clostridium sp. and Enterobacter cloacae. Batch experiment demonstrated that the highest H 2 producing activity was obtained at 55 °C and the ultimate hydrogen yield and the metabolic by-products were influenced greatly by temperatures. The effect of temperature variation showed that the activation energy for cellulose and glucose were estimated at 103 and 98.8 kJ mol −1 , respectively. - Highlights: • Continuous cellulosic-hydrogen fermentation was conducted at 55 °C. • Hydrogen yield was improved to 15.4 mol kg −1 of consumed-cellulose. • The cellulosic hydrogen bacteria were close to Clostridia and Enterobacter genus. • The mixed microflora produced H 2 within a wide range of temperatures (35 °C–65 °C). • Activation energy of cellulose and glucose were 103 and 98.8 kJ mol −1 , respectively

  10. Development of a simple bio-hydrogen production system through dark fermentation by using unique microflora

    Energy Technology Data Exchange (ETDEWEB)

    Ohnishi, Akihiro; Bando, Yukiko; Fujimoto, Naoshi; Suzuki, Masaharu [Department of Fermentation Science, Faculty of Applied Bio-Science, Tokyo University of Agriculture, 1-1 Sakuragaoka 1-chome, Setagaya-ku, Tokyo 156-8502 (Japan)

    2010-08-15

    In order to ensure efficient functioning of hydrogen fermentation systems that use Clostridium as the dominant hydrogen producer, energy-intensive process such as heat pretreatment of inoculum and/or substrate, continuous injection, and control of anaerobic conditions are required. Here, we describe a simple hydrogen fermentation system designed using microflora from leaf-litter cattle-waste compost. Hydrogen and volatile fatty acid production was measured at various hydraulic retention times, and bacterial genera were determined by PCR amplification and sequencing. Although hydrogen fermentation yield was approximately one-third of values reported in previous studies, this system requires no additional treatment and thus may be advantageous in terms of cost and operational control. Interestingly, Clostridium was absent from this system. Instead, Megasphaera elsdenii was the dominant hydrogen-producing bacterium, and lactic acid-producing bacteria (LAB) were prevalent. This study is the first to characterize M. elsdenii as a useful hydrogen producer in hydrogen fermentation systems. These results demonstrate that pretreatment is not necessary for stable hydrogen fermentation using food waste. (author)

  11. Design of neural network model-based controller in a fed-batch microbial electrolysis cell reactor for bio-hydrogen gas production

    Science.gov (United States)

    Azwar; Hussain, M. A.; Abdul-Wahab, A. K.; Zanil, M. F.; Mukhlishien

    2018-03-01

    One of major challenge in bio-hydrogen production process by using MEC process is nonlinear and highly complex system. This is mainly due to the presence of microbial interactions and highly complex phenomena in the system. Its complexity makes MEC system difficult to operate and control under optimal conditions. Thus, precise control is required for the MEC reactor, so that the amount of current required to produce hydrogen gas can be controlled according to the composition of the substrate in the reactor. In this work, two schemes for controlling the current and voltage of MEC were evaluated. The controllers evaluated are PID and Inverse neural network (NN) controller. The comparative study has been carried out under optimal condition for the production of bio-hydrogen gas wherein the controller output is based on the correlation of optimal current and voltage to the MEC. Various simulation tests involving multiple set-point changes and disturbances rejection have been evaluated and the performances of both controllers are discussed. The neural network-based controller results in fast response time and less overshoots while the offset effects are minimal. In conclusion, the Inverse neural network (NN)-based controllers provide better control performance for the MEC system compared to the PID controller.

  12. Biodiesel and biohydrogen production from cotton-seed cake in biorefinery concept

    NARCIS (Netherlands)

    Panagiotopoulos, I.A.; Pasias, S.; Bakker, R.R.C.; Vrije, de G.J.; Papayannakos, N.; Claassen, P.A.M.; Koukios, E.G.

    2013-01-01

    Biodiesel production from cotton-seed cake (CSC) and the pretreatment of the remaining biomass for dark fermentative hydrogen production was investigated. The direct conversion to biodiesel with alkali free fatty acids neutralization pretreatment and alkali transesterification resulted in a

  13. Biohydrogen production from arabinose and glucose using extreme thermophilic anaerobic mixed cultures

    DEFF Research Database (Denmark)

    De Abreu, Angela Alexandra Valente; Karakashev, Dimitar Borisov; Angelidaki, Irini

    2012-01-01

    .0 LH2 L-1 d-1 and hydrogen yield of 1.10 and 0.75 molH2 mol-1substrate for Rarab and Rgluc, respectively). Lower hydrogen production in Rgluc was associated with higher lactate production. DGGE results revealed no significant difference on the bacterial community composition between operational periods...

  14. Temperature effects on biohydrogen production in a granular sludge bed induced by activated carbon carriers

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kuo-Shing [Department of Safety Health and Environmental Engineering, Chung tai Institute of Health Sciences and Technology, Taichung (China); Lin, Ping-Jei [Department of Chemical Engineering, Feng Chia University, Taichung (China); Chang, Jo-Shu [Department of Chemical Engineering, National Cheng Kung University, Tainan (China)

    2006-03-15

    Temperature effects on H{sub 2} production performance of a novel carrier-induced granular sludge bed (CIGSB) reactor were investigated. Using sucrose-based synthetic wastewater as the feed, the CIGSB system was operated at 30-45 {sup 0}C to identify the optimal working temperature. It was found that H{sub 2} production was the most efficient at 40 {sup 0}C, especially when it was operated at a low hydraulic retention time (HRT) of 0.5h. The overall maximal hydrogen production rate and yield were 7.66l/h/l and 3.88mol H{sub 2}/mol sucrose, respectively, both of them occurred at 40 {sup 0}C. The biomass content tended to decrease as the temperature was increased, suggesting that granular sludge formation may be inhibited at high temperatures. However, increasing temperature gave better specific H{sub 2} production rate, signifying that the average cellular activity for H{sub 2} production may be enhanced as the temperature was increased. The H{sub 2} yield and gas phase H{sub 2} content did not vary considerably regardless of changes in temperature and HRT. This reflects that the CIGSB was a relatively stable H{sub 2}-producing system. The major soluble products from hydrogen fermentation were butyric acid and acetic acid, accounting for 46+-3% and 28+-2% of total soluble microbial products (SMP), respectively. Thus, the dominant H{sub 2} producers in the mixed culture belonged to acidogenic bacteria that underwent butyrate-type fermentation. (author)

  15. Genetic engineering of cyanobacteria to enhance biohydrogen production from sunlight and water.

    Science.gov (United States)

    Masukawa, Hajime; Kitashima, Masaharu; Inoue, Kazuhito; Sakurai, Hidehiro; Hausinger, Robert P

    2012-01-01

    To mitigate global warming caused by burning fossil fuels, a renewable energy source available in large quantity is urgently required. We are proposing large-scale photobiological H(2) production by mariculture-raised cyanobacteria where the microbes capture part of the huge amount of solar energy received on earth's surface and use water as the source of electrons to reduce protons. The H(2) production system is based on photosynthetic and nitrogenase activities of cyanobacteria, using uptake hydrogenase mutants that can accumulate H(2) for extended periods even in the presence of evolved O(2). This review summarizes our efforts to improve the rate of photobiological H(2) production through genetic engineering. The challenges yet to be overcome to further increase the conversion efficiency of solar energy to H(2) also are discussed.

  16. AnSBBR with circulation applied to biohydrogen production treating sucrose based wastewater: effects of organic loading, influent concentration and cycle length

    Directory of Open Access Journals (Sweden)

    D. A. Santos

    2014-09-01

    Full Text Available An anaerobic sequencing batch biofilm reactor (AnSBBR containing immobilized biomass and operating with recirculation of the liquid phase (total liquid volume 4.5 L; treated volume per cycle 1.9 L was used to treat sucrose-based wastewater at 30 ºC and produce biohydrogen. The influence of applied volumetric organic load was studied by varying the influent concentration at 3600 and 5400 mgCOD.L-1 and using cycle lengths of 4, 3 and 2 hours, obtaining in this manner volumetric organic loads of 9, 12, 13.5, 18 and 27 gCOD.L-1.d-1. Different performance indicators were used: productivity and yield of biohydrogen per applied and removed load, reactor stability and efficiency based on the applied and removed organic loads, both in terms of organic matter (measured as COD and carbohydrate (sucrose. The results revealed system stability (32-37% of H2 in biogas during biohydrogen production, as well as substrate consumption (12-19% COD; 97-99% sucrose. Conversion efficiencies decreased when the influent concentration was increased (at constant cycle length and when cycle lengths were reduced (at constant influent concentrations. The best yield was 4.16 mol-H2.kg-SUC-1 (sucrose load at 9 gCOD.L-1.d-1 (3600 mgCOD.L-1 and 4 h with H2 content in the biogas of 36% (64% CO2 and 0% CH4. However, the best specific molar productivity of hydrogen was 8.5 molH2.kgTVS-1.d-1 (32% H2; 68% CO2; 0% CH4, at 18 gCOD.L-1.d-1 (5400 mgCOD.L-1 and 3 h, indicating that the best productivity tends to occur at higher organic loads, as this parameter involves the "biochemical generation" of biogas, whereas the best yield tends to occur at lower and/or intermediate organic loads, as this parameter involves "biochemical consumption" of the substrate. The most significant metabolites were ethanol, acetic acid and butyric acid. Microbiological analyses revealed that the biomass contained bacilli and endospore filaments and showed no significant variations in morphology between

  17. Effect of food to microorganism ratio on biohydrogen production from food waste via anaerobic fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Jinming [Department of Biosystems Engineering, Zhejiang University, Hangzhou 310029 (China); Department of Biological and Agricultural Engineering, University of California at Davis, One Shields Avenue, Davis, CA 95616 (United States); Zhang, Ruihong; Sun, Huawei [Department of Biological and Agricultural Engineering, University of California at Davis, One Shields Avenue, Davis, CA 95616 (United States); El-Mashad, Hamed M. [Department of Biological and Agricultural Engineering, University of California at Davis, One Shields Avenue, Davis, CA 95616 (United States); Department of Agricultural Engineering, Mansoura University, El-Mansoura (Egypt); Ying, Yibin [Department of Biosystems Engineering, Zhejiang University, Hangzhou 310029 (China)

    2008-12-15

    The effect of different food to microorganism ratios (F/M) (1-10) on the hydrogen production from the anaerobic batch fermentation of mixed food waste was studied at two temperatures, 35 {+-} 2 C and 50 {+-} 2 C. Anaerobic sludge taken from anaerobic reactors was used as inoculum. It was found that hydrogen was produced mainly during the first 44 h of fermentation. The F/M between 7 and 10 was found to be appropriate for hydrogen production via thermophilic fermentation with the highest yield of 57 ml-H{sub 2}/g VS at an F/M of 7. Under mesophilic conditions, hydrogen was produced at a lower level and in a narrower range of F/Ms, with the highest yield of 39 ml-H{sub 2}/g VS at the F/M of 6. A modified Gompertz equation adequately (R{sup 2} > 0.946) described the cumulative hydrogen production yields. This study provides a novel strategy for controlling the conditions for production of hydrogen from food waste via anaerobic fermentation. (author)

  18. Halophilic biohydrogen and 1,3-propanediol production from raw glycerol: A genomic perspective

    Energy Technology Data Exchange (ETDEWEB)

    Kivisto, A.

    2013-11-01

    Glycerol is produced in large amounts as a by-product in biodiesel industry (10 kg per 100 kg biodiesel). By-products and waste materials are typically economical substrates for bioprocesses. Furthermore, microorganisms are able to combine the degradation of organic material with production of a wide range of metabolites and other cellular products. The current biotechnological interest of industrial glycerol lies on bioprocesses yielding environmentally friendly energy carrier molecules (hydrogen, methane, ethanol, butanol) and reduced chemicals (1,3-propanediol, dihydroxyacetone). Industrial glycerol also called as raw or crude glycerol, however, is a challenging substrate for microorganisms due to its impurities including alcohol, soaps, salts and metals. Halophiles (the salt-loving microorganisms) require salt for growth and heavy metal resistances have been characterized for numerous halophiles. Therefore, halophiles are potentially useful for the utilization of raw glycerol from biodiesel waste streams without pre-processing. Another challenge for large-scale microbial bioprocesses is a potential contamination with unfavorable microorganisms. For example, H{sub 2}-producing systems tend to get contaminated with H{sub 2}-consuming microorganisms. Extremophiles are organisms that have been adapted for life under extreme conditions, such as high salinity, high or low temperature, asidic or basic pH, dryness or high pressure. For extremophilic pure cultures contamination and thus the need to ensure a sterile environment might not be a problem due to the extreme process conditions that efficiently prevent the growth of most other bacteria. In addition, hypersaline environments (above 12 % NaCl) do not support the growth of H{sub 2} utilizing methanogens due to bioenergetic reasons. Halophilic fermentative H{sub 2} producers, on the other hand, have been shown to be active up to near salt saturation. The aims of the present study can be divided into two categories

  19. Microbial culture selection for bio-hydrogen production from waste ground wheat by dark fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Argun, Hidayet; Kargi, Fikret; Kapdan, Ilgi K. [Department of Environmental Engineering, Dokuz Eylul University, Buca, Izmir (Turkey)

    2009-03-15

    Hydrogen formation performances of different anaerobic bacteria were investigated in batch dark fermentation of waste wheat powder solution (WPS). Serum bottles containing wheat powder were inoculated with pure cultures of Clostridium acetobutylicum (CAB), Clostridium butyricum (CB), Enterobacter aerogenes (EA), heat-treated anaerobic sludge (ANS) and a mixture of those cultures (MIX). Cumulative hydrogen formation (CHF), hydrogen yield (HY) and specific hydrogen production rate (SHPR) were determined for every culture. The heat-treated anaerobic sludge was found to be the most effective culture with a cumulative hydrogen formation of 560 ml, hydrogen yield of 223 ml H{sub 2} g{sup -1} starch and a specific hydrogen production rate of 32.1 ml H{sub 2} g{sup -1} h{sup -1}. (author)

  20. Biohydrogen production from dual digestion pretreatment of poultry slaughterhouse sludge by anaerobic self-fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Sittijunda, Sureewan [Department of Biotechnology, Faculty of Technology, Khon Kaen University, Khon Kaen 40002 (Thailand); Reungsang, Alissara [Department of Biotechnology, Faculty of Technology, Khon Kaen University, Khon Kaen 40002 (Thailand); Fermentation Research Center for Value Added Agricultural Products, Khon Kaen University, Khon Kaen 40002 (Thailand); O-thong, Sompong [Department of Biology, Faculty of Science, Thaksin University, Patthalung 93110 (Thailand)

    2010-12-15

    Poultry slaughterhouse sludge from chicken processing wastewater treatment plant was tested for their suitability as a substrate and inoculum source for fermentation hydrogen production. Dual digestion of poultry slaughterhouse sludge was employed to produce hydrogen by batch anaerobic self-fermentation without any extra-seeds. The sludge (5% TS) was dual digested by aerobic thermophilic digestion at 55 C with the varying retention time before using as substrate in anaerobic self-fermentation. The best digestion time for enriching hydrogen-producing seeds was 48 h as it completely repressed methanogenic activity and gave the maximum hydrogen yield of 136.9 mL H{sub 2}/g TS with a hydrogen production rate of 2.56 mL H{sub 2}/L/h. The hydrogen production of treated sludge at 48 h (136.9 mL H{sub 2}/g TS) was 15 times higher than that of the raw sludge (8.83 mL H{sub 2}/g TS). With this fermentation process, tCOD value in the activated sludge could be reduced up to 30%. (author)

  1. Screening for biohydrogen production by cyanobacteria isolated from the Baltic Sea and Finnish lakes

    Energy Technology Data Exchange (ETDEWEB)

    Allahverdiyeva, Yagut; Leino, Hannu; Shunmugam, Sumathy; Aro, Eva-Mari [Department of Biochemistry and Food Chemistry, Plant Physiology and Molecular Biology, University of Turku, Tykistokatu 6 A, FIN-20014 Turku (Finland); Saari, Lyudmila; Fewer, David P.; Sivonen, Kaarina [Department of Applied Chemistry and Microbiology, University of Helsinki, P.O. Box 56, FI-00014 (Finland)

    2010-02-15

    Cyanobacteria are the only bacteria capable of performing oxygenic photosynthesis in which they harness solar energy and convert it into chemical energy stored in carbohydrates. Under specific conditions, cyanobacteria can use solar energy to produce also molecular hydrogen. Biodiversity among cyanobacteria for H{sub 2} production has not been efficiently studied. Here we report the screening of 400 cyanobacterial strains isolated from the Baltic Sea and Finnish lakes for efficient H{sub 2} producers. Approximately 50% of these strains produced detectable amounts of H{sub 2}. Ten strains produced similar or up to 4 times as much of H{sub 2} as the hydrogenase mutants of Anabaena PCC 7120 and Nostoc punctiforme ATCC 29133 specifically engineered in different laboratories to produce higher amounts of H{sub 2}. All ten H{sub 2} producers are N{sub 2}-fixing filamentous, heterocystous strains, seven of them are benthic and three are planktonic strains. Different culturing parameters, such as light intensity, cell density, pH and temperature had a pronounced effect on the H{sub 2} production rates of the two good H{sub 2} producers, Calothrix 336/3 and XPORK 5E strains. Notably, the culture conditions for optimal H{sub 2} production varied between different cyanobacterial strains. (author)

  2. Dark fermentative biohydrogen production by mesophilic bacterial consortia isolated from riverbed sediments

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Sneha; Sudhakaran, Anu K.; Sarma, Priyangshu Manab; Subudhi, Sanjukta; Mandal, Ajoy Kumar; Lal, Banwari [Environmental and Industrial Biotechnology Division, The Energy and Resources Institute (TERI), Habitat Place, Darbari Seth Block, Lodhi Road, New Delhi 110003 (India); Gandham, Ganesh [Hindustan Petroleum Corporation Limited, Mumbai Refinery, B. D. Patil Marg, Mahul, Mumbai 400074 (India)

    2010-10-15

    Dark fermentative bacterial strains were isolated from riverbed sediments and investigated for hydrogen production. A series of batch experiments were conducted to study the effect of pH, substrate concentration and temperature on hydrogen production from a selected bacterial consortium, TERI BH05. Batch experiments for fermentative conversion of sucrose, starch, glucose, fructose, and xylose indicated that TERI BH05 effectively utilized all the five sugars to produce fermentative hydrogen. Glucose was the most preferred carbon source indicating highest hydrogen yields of 22.3 mmol/L. Acetic and butyric acid were the major soluble metabolites detected. Investigation on optimization of pH, temperature, and substrate concentration revealed that TERI BH05 produced maximum hydrogen at 37 C, pH 6 with 8 g/L of glucose supplementation and maximum yield of hydrogen production observed was 2.0-2.3 mol H{sub 2}/mol glucose. Characterization of TERI BH05 revealed the presence of two different bacterial strains showing maximum homology to Clostridium butyricum and Clostridium bifermentans. (author)

  3. Enhancing biohydrogen production through sewage supplementation of composite vegetable based market waste

    International Nuclear Information System (INIS)

    Mohanakrishna, G.; Kannaiah Goud, R.; Venkata Mohan, S.; Sarma, P.N.

    2010-01-01

    The function of domestic sewage supplementation as co-substrate with composite vegetable based market waste was studied during the process of fermentative hydrogen (H 2 ) production. Significant improvement in H 2 production and substrate degradation were noticed upon supplementing the waste with domestic sewage. Maximum H 2 production (cummulative) was observed at 5.2 kg COD/m 3 with pulp operation and 4.8 kg COD/m 3 with non-pulp operation accounting for improvement of 51 and 55% respectively after sewage upplementation. Substrate degradation was also found to improve with respect to both carbohydrates [8% (with pulp); 5% (non-pulp)] and chemical oxygen demand [COD, 12% (with pulp); 13% (non-pulp)] after adding domestic sewage. Specific H 2 yield improved especially at lower concentrations. Supplementation of waste with co-substrate helps to maintain good buffering microenvironment supports fermentation process and in addition provides micro-nutrients, organic matter and microbial biomass. Variation in the outlet pH was less in supplementation experiments compared to normal operation. (author)

  4. Bio-hydrogen production from waste fermentation. Mixing and static conditions

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, X.; Cuetos, M.J.; Prieto, J.I.; Moran, A. [Chemical Engineering Dept. IRENA, University of Leon, Avda. de Portugal 41, 24071 Leon (Spain)

    2009-04-15

    One of the main disadvantages of the dark fermentation process is the cost associated with the stages needed for obtaining H{sub 2} producing microorganisms. Using anaerobic microflora in fermentation systems directly is an alternative which is gaining special interest when considering the implementation of large-scale plants and the use of wastes as substrate material. The performance of two H{sub 2} producing microflora obtained from different anaerobic cultures was studied in this paper. Inoculum obtained from a waste sludge digester and from a laboratory digester treating slaughterhouse wastes were used to start up H{sub 2} fermentation systems. Inoculum acclimatized to slaughterhouse wastes gave better performance in terms of stability. However, due to the limited availability of this seed material, further work was performed to study the behaviour of the inoculum obtained from the municipal wastewater treatment plant. The process was evaluated under static and mixing conditions. It was found that application of a low organic loading rate favoured the performance of the fermentation systems, and that agitation of the reacting mass could alleviate unsteady performance. Specific H{sub 2} production obtained was in the range of 19-26 L/kg SV{sub fed} with maximum peak production of 38-67 L/kg SV{sub fed}. Although the performance of the systems was unsteady, recovery could be achieved by suspending the feeding process and controlling the pH in the range of 5.0-5.5. Testing the recovery capacity of the systems under temperature shocks resulted in total stoppage of H{sub 2} production. (author)

  5. Biohydrogen production from xylose at extreme thermophilic temperatures (70 degrees C) by mixed culture fermentation

    DEFF Research Database (Denmark)

    Kongjan, Prawit; Min, Booki; Angelidaki, Irini

    2009-01-01

    /L. Addition of yeast extract in the cultivation medium resulted in significant improvement of hydrogen yield. The main metabolic products during xylose fermentation were acetate, ethanol, and lactate. The specific growth rates were able to fit the experimental points relatively well with Haldane equation...... solid wastes at 70 degrees C. The highest hydrogen yield of 1.62 +/- 0.02 mol-H-2/Mol-xylose(consumed) was obtained at initial xylose concentration of 0.5 g/L with synthetic medium amended with I g/L of yeast extract. Lower hydrogen yield was achieved at initial xylose concentration higher than 2 g...

  6. Biohydrogen production behaviour and molecular characterization of a new species of anaerobic bacterium

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y.; Ren, N.; Chen, Y.; Li, J.; Zheng, G. [Harbin Inst. of Technology Harbin, HL (China). Municipal and Environmental School; Yang, C. [Univ. of Northeast Forestry, Harbin, HL (China)

    2004-07-01

    Since the isolation of the first anaerobic hydrogen-producing microbe in 1994, this method of hydrogen production from organic wastewater has received much attention. Presently the main candidate bacteria come from the Clostridium genus and the Enterobacter genus. A practical technology is probably not possible with these and their genetic basis is narrow. This paper reports on a new species which is perhaps a member of a new genus. The authors base these conclusions on physiological and biochemical traits, morphological characteristics, and the 16 Sr DNA sequence. The hydrogen-producing capacity was measured. The temporary nomenclature of the genus is Biohydrogenbacterium and the temporary nomenclature of the species is Rennanqiliyongfengii sp. nov. 12 refs., 1 tab., 3 figs.

  7. Comparison of bio-hydrogen production yield capacity between asynchronous and simultaneous saccharification and fermentation processes from agricultural residue by mixed anaerobic cultures.

    Science.gov (United States)

    Li, Yameng; Zhang, Zhiping; Zhu, Shengnan; Zhang, Huan; Zhang, Yang; Zhang, Tian; Zhang, Quanguo

    2018-01-01

    Taken common agricultural residues as substrate, dark fermentation bio-hydrogen yield capacity from asynchronous saccharification and fermentation (ASF) and simultaneous saccharification and fermentation (SSF) was investigated. The highest hydrogen yield of 472.75mL was achieved with corncob using ASF. Hydrogen yield from corn straw, rice straw, corncob and sorghum stalk by SSF were 20.54%,10.31%,13.99% and 5.92% higher than ASF, respectively. The experimental data fitted well to the modified Gompertz model. SSF offered a distinct advantage over ASF with respect to reducing overall process time (60h of SSF, 108h of ASF). Meanwhile, SSF performed better than SSF with respect to shortening the lag-stage. The major metabolites of anaerobic fermentation hydrogen production by ASF and SSF were butyric acid and acetic acid. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Econometric models for biohydrogen development.

    Science.gov (United States)

    Lee, Duu-Hwa; Lee, Duu-Jong; Veziroglu, Ayfer

    2011-09-01

    Biohydrogen is considered as an attractive clean energy source due to its high energy content and environmental-friendly conversion. Analyzing various economic scenarios can help decision makers to optimize development strategies for the biohydrogen sector. This study surveys econometric models of biohydrogen development, including input-out models, life-cycle assessment approach, computable general equilibrium models, linear programming models and impact pathway approach. Fundamentals of each model were briefly reviewed to highlight their advantages and disadvantages. The input-output model and the simplified economic input-output life-cycle assessment model proved most suitable for economic analysis of biohydrogen energy development. A sample analysis using input-output model for forecasting biohydrogen development in the United States is given. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Production of Bio-Hydrogenated Diesel by Hydrotreatment of High-Acid-Value Waste Cooking Oil over Ruthenium Catalyst Supported on Al-Polyoxocation-Pillared Montmorillonite

    Directory of Open Access Journals (Sweden)

    Kinya Sakanishi

    2012-02-01

    Full Text Available Waste cooking oil with a high-acid-value (28.7 mg-KOH/g-oil was converted to bio-hydrogenated diesel by a hydrotreatment process over supported Ru catalysts. The standard reaction temperature, H2 pressure, liquid hourly space velocity (LHSV, and H2/oil ratio were 350 °C, 2 MPa, 15.2 h–1, and 400 mL/mL, respectively. Both the free fatty acids and the triglycerides in the waste cooking oil were deoxygenated at the same time to form hydrocarbons in the hydrotreatment process. The predominant liquid hydrocarbon products (98.9 wt% were n-C18H38, n-C17H36, n-C16H34, and n-C15H32 when a Ru/SiO2 catalyst was used. These long chain normal hydrocarbons had high melting points and gave the liquid hydrocarbon product over Ru/SiO2 a high pour point of 20 °C. Ru/H-Y was not suitable for producing diesel from waste cooking oil because it formed a large amount of C5–C10 gasoline-ranged paraffins on the strong acid sites of HY. When Al-polyoxocation-pillared montmorillonite (Al13-Mont was used as a support for the Ru catalyst, the pour point of the liquid hydrocarbon product decreased to −15 °C with the conversion of a significant amount of C15–C18 n-paraffins to iso-paraffins and light paraffins on the weak acid sites of Al13-Mont. The liquid product over Ru/Al13-Mont can be expected to give a green diesel for current diesel engines because its chemical composition and physical properties are similar to those of commercial petro-diesel. A relatively large amount of H2 was consumed in the hydrogenation of unsaturated C=C bonds and the deoxygenation of C=O bonds in the hydrotreatment process. A sulfided Ni-Mo/Al13-Mont catalyst also produced bio-hydrogenated diesel by the hydrotreatment process but it showed slow deactivation during the reaction due to loss of sulfur. In contrast, Ru/Al13-Mont did not show catalyst deactivation in the hydrotreatment of waste cooking oil after 72 h on-stream because the waste cooking oil was not found to contain sulfur

  10. Study on Molasses Concentration from Sugarcanne Bagasse for Biohydrogen Production using Enriched Granular Activated Carbon (GAC) Immobilised Cells by Repeated Batch Cultivation

    Science.gov (United States)

    Idris, Norfatiha; Aminah Lutpi, Nabilah; Ruhaizul Che Ridzuan, Che Mohd; Shian, Wong Yee; Nuraiti Tengku Izhar, Tengku

    2018-03-01

    Repeated batch cultivation is known as most attractive method in improving hydrogen productivity, due to the facts that this approach could minimize the reuse of the cell and the inoculum preparation. In addition, with the combination of attach growth system during the fermentation processes to produce biohydrogen, the density of cells will be increased and the cell washout could be avoided. Therefore, this study aimed to examine the effectiveness of repeated batch cultivation for enrichment of anaerobic mixed culture onto granular activated carbon (GAC) and investigate the effect of molasses concentration during immobilization of mixed culture onto the GAC. The molasses concentration using 50 %, 40 %, 30 %, 20 % and 10 % of diluted molasses were used as feedstock in the fermentation process. The maximum hydrogen production of 60 ml was obtained at 30 % of molasses concentration with 831 ppm of hydrogen concentration. Thus, the kinetic parameter obtained from the batch profiling based on modified Gompertz equation are, Hm= 58 ml for the maximum hydrogen production and Rm= 2.02 ml/h representing the hydrogen production rate.

  11. Biohydrogen from thermophilic co-fermentation of swine manure with fruit and vegetable waste: maximizing stable production without pH control.

    Science.gov (United States)

    Tenca, A; Schievano, A; Perazzolo, F; Adani, F; Oberti, R

    2011-09-01

    Hydrogen production by dark fermentation may suffer of inhibition or instability due to pH deviations from optimality. The co-fermentation of promptly degradable feedstock with alkali-rich materials, such as livestock wastes, may represent a feasible and easy to implement approach to avoid external adjustments of pH. Experiments were designed to investigate the effect of the mixing ratio of fruit-vegetable waste with swine manure with the aim of maximizing biohydrogen production while obtaining process stability through the endogenous alkalinity of manure. Fruit-vegetable/swine manure ratio of 35/65 and HRT of 2d resulted to give the highest production rate of 3.27 ± 0.51 L(H2)L(-1)d(-1), with a corresponding hydrogen yield of 126 ± 22 mL(H2)g(-1)(VS-added) and H2 content in the biogas of 42 ± 5%. At these operating conditions the process exhibited also one of the highest measured stability, with daily productions deviating for less than 14% from the average. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Thermophilic anaerobic co-digestion of organic fraction of municipal solid waste (OFMSW) with food waste (FW): Enhancement of bio-hydrogen production.

    Science.gov (United States)

    Angeriz-Campoy, Rubén; Álvarez-Gallego, Carlos J; Romero-García, Luis I

    2015-10-01

    Bio-hydrogen production from dry thermophilic anaerobic co-digestion (55°C and 20% total solids) of organic fraction of municipal solid waste (OFMSW) and food waste (FW) was studied. OFMSW coming from mechanical-biological treatment plants (MBT plants) presents a low organic matter concentration. However, FW has a high organic matter content but several problems by accumulation of volatile fatty acids (VFAs) and system acidification. Tests were conducted using a mixture ratio of 80:20 (OFSMW:FW), to avoid the aforementioned problems. Different solid retention times (SRTs) - 6.6, 4.4, 2.4 and 1.9 days - were tested. It was noted that addition of food waste enhances the hydrogen production in all the SRTs tested. Best results were obtained at 1.9-day SRT. It was observed an increase from 0.64 to 2.51 L H2/L(reactor) day in hydrogen productivity when SRTs decrease from 6.6 to 1.9 days. However, the hydrogen yield increases slightly from 33.7 to 38 mL H2/gVS(added). Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Sequential dark-photo fermentation and autotrophic microalgal growth for high-yield and CO{sub 2}-free biohydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Yung-Chung [Department of Chemical Engineering, National Cheng Kung University, Tainan 701 (China); Chen, Chun-Yen [Department of Chemical Engineering, National Cheng Kung University, Tainan 701 (China); Sustainable Environment Research Center, National Cheng Kung University, Tainan (China); Lee, Chi-Mei [Department of Environmental Engineering, National Chung Hsing University, Taichung (China); Chang, Jo-Shu [Department of Chemical Engineering, National Cheng Kung University, Tainan 701 (China); Sustainable Environment Research Center, National Cheng Kung University, Tainan (China); Center for Biosciences and Biotechnology, National Cheng Kung University, Tainan (China)

    2010-10-15

    Dark fermentation, photo fermentation, and autotrophic microalgae cultivation were integrated to establish a high-yield and CO{sub 2}-free biohydrogen production system by using different feedstock. Among the four carbon sources examined, sucrose was the most effective for the sequential dark (with Clostridium butyricum CGS5) and photo (with Rhodopseudomonas palutris WP3-5) fermentation process. The sequential dark-photo fermentation was stably operated for nearly 80 days, giving a maximum H{sub 2} yield of 11.61 mol H{sub 2}/mol sucrose and a H{sub 2} production rate of 673.93 ml/h/l. The biogas produced from the sequential dark-photo fermentation (containing ca. 40.0% CO{sub 2}) was directly fed into a microalga culture (Chlorella vulgaris C-C) cultivated at 30 C under 60 {mu}mol/m{sup 2}/s illumination. The CO{sub 2} produced from the fermentation processes was completely consumed during the autotrophic growth of C. vulgaris C-C, resulting in a microalgal biomass concentration of 1999 mg/l composed mainly of 48.0% protein, 23.0% carbohydrate and 12.3% lipid. (author)

  14. Biohydrogen and methane production by co-digestion of cassava stillage and excess sludge under thermophilic condition.

    Science.gov (United States)

    Wang, Wen; Xie, Li; Chen, Jinrong; Luo, Gang; Zhou, Qi

    2011-02-01

    Thermophilic anaerobic hydrogen and methane production by co-digestion of cassava stillage (CS) and excess sludge (ES) was investigated in this study. The improved hydrogen and subsequent methane production were observed by co-digestion of CS with certain amount of ES in batch experiments. Compared with one phase anaerobic digestion, two phase anaerobic digestion offered an attractive alternative with more abundant biogas production and energy yield, e.g., the total energy yield in two phase obtained at VS(CS)/VS(ES) of 3:1 was 25% higher than the value of one phase. Results from continuous experiments further demonstrated that VS(CS)/VS(ES) of 3:1 was optimal for hydrogen production with the highest hydrogen yield of 74 mL/gtotal VS added, the balanced nutrient condition with C/N ratio of 1.5 g carbohydrate-COD/gprotein-COD or 11.9 g C/gN might be the main reason for such enhancement. VS(CS)/VS(ES) of 3:1 was also optimal for continuous methane production considering the higher methane yield of 350 mL/gtotal VS added and the lower propionate concentration in the effluent. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Performance evaluation and phylogenetic characterization of anaerobic fluidized bed reactors using ground tire and pet as support materials for biohydrogen production.

    Science.gov (United States)

    Barros, Aruana Rocha; Adorno, Maria Angela Tallarico; Sakamoto, Isabel Kimiko; Maintinguer, Sandra Imaculada; Varesche, Maria Bernadete Amâncio; Silva, Edson Luiz

    2011-02-01

    This study evaluated two different support materials (ground tire and polyethylene terephthalate [PET]) for biohydrogen production in an anaerobic fluidized bed reactor (AFBR) treating synthetic wastewater containing glucose (4000 mg L(-1)). The AFBR, which contained either ground tire (R1) or PET (R2) as support materials, were inoculated with thermally pretreated anaerobic sludge and operated at a temperature of 30°C. The AFBR were operated with a range of hydraulic retention times (HRT) between 1 and 8h. The reactor R1 operating with a HRT of 2h showed better performance than reactor R2, reaching a maximum hydrogen yield of 2.25 mol H(2)mol(-1) glucose with 1.3mg of biomass (as the total volatile solids) attached to each gram of ground tire. Subsequent 16S rRNA gene sequencing and phylogenetic analysis of particle samples revealed that reactor R1 favored the presence of hydrogen-producing bacteria such as Clostridium, Bacillus, and Enterobacter. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. Nickel-graphene nanocomposite as a novel supplement for enhancement of biohydrogen production from industrial wastewater containing mono-ethylene glycol

    International Nuclear Information System (INIS)

    Elreedy, Ahmed; Ibrahim, Eman; Hassan, Nazly; El-Dissouky, Ali; Fujii, Manabu; Yoshimura, Chihiro; Tawfik, Ahmed

    2017-01-01

    Highlights: • Ni-graphene nanocomposite (Ni-Gr NC) showed superiority in biohydrogenation process. • Ni-Gr NC dose of 60 mg/L exhibited the highest improvement (105%) in H_2 production. • H_2 production was improved by 67% compared with supplementation of Ni nanoparticles. • Graphene presence in Ni-Gr NC didn’t show additional inhibition at the higher doses. • Net profit from energy recovery, including nanomaterials cost, was improved by 21%. - Abstract: The impact of Ni nanoparticles (NPs) and Ni-graphene nanocomposite (Ni-Gr NC) on hydrogen production from industrial wastewater containing mono-ethylene glycol (MEG) via anaerobic digestion was investigated. Batch reactors were supplemented with different dosages of Ni NPs and Ni-Gr NC ranging from 0 to 100 mg/L. Maximum hydrogen yields (HYs) of 24.73 ± 1.12 and 41.28 ± 1.69 mL/gCOD_i_n_i_t_i_a_l were achieved at a dosage of 60 mg/L for Ni NPs and Ni-Gr NC, respectively. Substantial improvements of 23% and 105% in hydrogen production were registered at an optimum dosage of 60 mg/L for Ni NPs and Ni-Gr NC, respectively, compared with the control without nanomaterials addition. However, increasing the dosage of Ni NPs and Ni-Gr NC to 100 mg/L resulted in a significant decrease in HY to 20.80 ± 1.12 and 24.24 ± 1.13 mL/gCOD_i_n_i_t_i_a_l, respectively. A non-linear regression model revealed that the higher maximum hydrogen production (129% improvement) could be achieved at a dosage of 50 mg/L Ni-Gr NC and an initial pH of 5.0. Economic and environmental revenues due to bioenergy recovery from MEG-containing wastewater were also estimated.

  17. Reusing pulp and paper mill effluent as a bioresource to produce biohydrogen through ultrasonicated Rhodobacter sphaeroides

    International Nuclear Information System (INIS)

    Hay, Jacqueline Xiao Wen; Wu, Ta Yeong; Ng, Boon Junn; Juan, Joon Ching; Md Jahim, Jamaliah

    2016-01-01

    Highlights: • Ultrasonication pretreatment on R. sphaeroides enhanced biohydrogen production. • Pretreatment using amplitude 30% for 10 min gave the highest biohydrogen yield. • Pretreatment using amplitude 45% for 15 min inhibited biohydrogen production. - Abstract: Pulp and paper industry is a water-intensive industry. This industry commonly produces considerable amount of effluent, especially from virgin raw materials processing. The effluent, namely pulp and paper mill effluent has the potential to adversely affect the receiving watercourses. However, the nutrients in the pulp and paper mill effluent could be reused as a substrate in biohydrogen production. In this study, photofermentative biohydrogen production was investigated using Rhodobacter sphaeroides and pulp and paper mill effluent as a substrate. An application of low power ultrasound on R. sphaeroides was predicted to increase photofermentative biohydrogen production but excessive ultrasound effects might inhibit the production due to possible cell disruption. Hence, various ultrasonication duration (5, 10 and 15 min) and amplitude (15%, 30% and 45%) were applied on the bacteria to determine the recommended ultrasonication conditions for improving biohydrogen production. The recommended conditions were operated at ultrasonication amplitude and duration of 30% and 10 min, respectively. A maximum biohydrogen yield of 9.62 mL bioH_2/mL medium was obtained under this condition, which was 66.7% higher than the result obtained using R. sphaeroides without undergoing ultrasonication (control). The light efficiency and cell concentration were increased by 67% and 150%, respectively, using ultrasonication amplitude and duration of 30% and 10 min, respectively as compared to the control. The present results demonstrated that moderate power of ultrasonication applied on R. sphaeroides was an effective method for enhancing photofermentative biohydrogen production using raw pulp and paper mill effluent as a

  18. Biohydrogen production from combined dark-photo fermentation under a high ammonia content in the dark fermentation effluent

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chun-Yen [National Cheng Kung Univ., Tainan, Taiwan (China). Dept. of Chemical Engineering; National Cheng Kung Univ., Tainan, Taiwan (China). Sustainable Environment Research Center; Lo, Yung-Chung; Yeh, Kuei-Ling [National Cheng Kung Univ., Tainan, Taiwan (China). Dept. of Chemical Engineering; Chang, Jo-Shu [National Cheng Kung Univ., Tainan, Taiwan (China). Dept. of Chemical Engineering; National Cheng Kung Univ., Tainan, Taiwan (China). Sustainable Environment Research Center; National Cheng Kung Univ., Tainan, Taiwan (China). Microalgae Biotechnology and Bioengineering Lab.

    2010-07-01

    Integrated dark and photo (two-stage) fermentation was employed to enhance the performance of H{sub 2} production. First, the continuous dark fermentation using indigenous Clostridium butyricum CGS5 was carried out at 12 h HRT and fed with sucrose at a concentration of 18750 mg/l. The overall H{sub 2} production rate and H{sub 2} yield were fairly stable with a mean value of 87.5 ml/l/h and 1.015 mol H{sub 2}/mol sucrose, respectively. In addition, a relatively high ammonia nitrogen content (574 mg/l) in the dark fermentation effluent was observed. The soluble metabolites from dark fermentation, consisting mainly of butyric, lactic and acetic acids, were directly used as the influent of continuous photo-H{sub 2} production process inoculated with Rhodopseudomonas palutris WP 3-5 under the condition of 35oC, 10000 lux irradiation, pH 7.0 and 48 h HRT. The maximum overall hydrogen production rate from photo fermentation was 16.4 ml H{sub 2}/l/h, and the utilization of the soluble metabolites could reach 90%. The maximum H{sub 2} yield dramatically increased from 1.015 mol H{sub 2}/mol sucrose (in dark fermentation only) to 6.04 mol H{sub 2}/mol sucrose in the combined dark and photo fermentation. Surprisingly, the operation strategy applied in this work was able to attain an average NH{sub 3}-N removal efficiency of 92%, implying that our photo-H{sub 2} production system has a higher NH{sub 3}-N tolerance, demonstrating its high applicability in an integrated dark-photo fermentation system. (orig.)

  19. Continuous biodisel productions: A review

    Directory of Open Access Journals (Sweden)

    Stamenković Ivica S.

    2009-01-01

    Full Text Available Continuous biodiesel production on laboratory and industrial scale was analyzed, with focus on their advantages and disadvantages. Attention was paid to specific characteristics of industrial processes in order to point out the advanced technologies. The well-known base-catalyzed continuous biodiesel production processes are related to problems caused by the immiscibility of the reactants (alcohol and oil, application of relatively high operating temperature (usually the boiling temperature of alcohol or one near it and obtained yield of methyl ester yields lower than desired. One way to overcome these problems is to employ special reactor design favoring the emulsion process and increasing the overall rate of biodiesel production process, even at room temperature and atmospheric pressure. The second way is to apply heterogeneous catalysts in continuous processes, which will probably be the optimal approach to economically justified and environmentally friendly biodiesel production.

  20. Biohydrogen production from desugared molasses (DM) using thermophilic mixed cultures immobilized on heat treated anaerobic sludge granules

    DEFF Research Database (Denmark)

    Kongjan, Prawit; O-Thong, Sompong; Angelidaki, Irini

    2011-01-01

    Hydrogen production from desugared molasses (DM) was investigated in both batch and continuous reactors using thermophilic mixed cultures enriched from digested manure by load shock (loading with DM concentration of 50.1 g-sugar/L) to suppress methanogens. H2 gas, free of methane, was produced......) and Thermoanaerobacterium thermosaccharolyticum with a relative abundance of 36%, 27%, and 10% of total microorganisms, respectively. This study shows that hydrogen production could be efficiently facilitated by using anaerobic granules as a carrier, where microbes from mixed culture enriched in the DM batch cultivation....... The enriched hydrogen producing mixed culture achieved from the 16.7 g-sugars/L DM batch cultivation was immobilized on heat treated anaerobic sludge granules in an up-flow anaerobic sludge blanket (UASB) reactor. The UASB reactor, operated at a hydraulic retention time (HRT) of 24 h fed with 16.7 g...

  1. Looking for practical tools to achieve next-future applicability of dark fermentation to produce bio-hydrogen from organic materials in Continuously Stirred Tank Reactors.

    Science.gov (United States)

    Tenca, A; Schievano, A; Lonati, S; Malagutti, L; Oberti, R; Adani, F

    2011-09-01

    This study aimed at finding applicable tools for favouring dark fermentation application in full-scale biogas plants in the next future. Firstly, the focus was obtaining mixed microbial cultures from natural sources (soil-inocula and anaerobically digested materials), able to efficiently produce bio-hydrogen by dark fermentation. Batch reactors with proper substrate (1 gL(glucose)(-1)) and metabolites concentrations, allowed high H(2) yields (2.8 ± 0.66 mol H(2)mol(glucose)(-1)), comparable to pure microbial cultures achievements. The application of this methodology to four organic substrates, of possible interest for full-scale plants, showed promising and repeatable bio-H(2) potential (BHP=202 ± 3 NL(H2)kg(VS)(-1)) from organic fraction of municipal source-separated waste (OFMSW). Nevertheless, the fermentation in a lab-scale CSTR (nowadays the most diffused typology of biogas-plant) of a concentrated organic mixture of OFMSW (126 g(TS)L(-1)) resulted in only 30% of its BHP, showing that further improvements are still needed for future full-scale applications of dark fermentation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. The influence of total solids content and initial pH on batch biohydrogen production by solid substrate fermentation of agroindustrial wastes.

    Science.gov (United States)

    Robledo-Narváez, Paula N; Muñoz-Páez, Karla M; Poggi-Varaldo, Hector M; Ríos-Leal, Elvira; Calva-Calva, Graciano; Ortega-Clemente, L Alfredo; Rinderknecht-Seijas, Noemí; Estrada-Vázquez, Carlos; Ponce-Noyola, M Teresa; Salazar-Montoya, J Alfredo

    2013-10-15

    Hydrogen is a valuable clean energy source, and its production by biological processes is attractive and environmentally sound and friendly. In México 5 million tons/yr of agroindustrial wastes are generated; these residues are rich in fermentable organic matter that can be used for hydrogen production. On the other hand, batch, intermittently vented, solid substrate fermentation of organic waste has attracted interest in the last 10 years. Thus the objective of our work was to determine the effect of initial total solids content and initial pH on H2 production in batch fermentation of a substrate that consisted of a mixture of sugarcane bagasse, pineapple peelings, and waste activated sludge. The experiment was a response surface based on 2(2) factorial with central and axial points with initial TS (15-35%) and initial pH (6.5-7.5) as factors. Fermentation was carried out at 35 °C, with intermittent venting of minireactors and periodic flushing with inert N2 gas. Up to 5 cycles of H2 production were observed; the best treatment in our work showed cumulative H2 productions (ca. 3 mmol H2/gds) with 18% and 6.65 initial TS and pH, respectively. There was a significant effect of TS on production of hydrogen, the latter decreased with initial TS increase from 18% onwards. Cumulative H2 productions achieved in this work were higher than those reported for organic fraction of municipal solid waste (OFMSW) and mixtures of OFMSW and fruit peels waste from fruit juice industry, using the same process. Specific energetic potential due to H2 in our work was attractive and fell in the high side of the range of reported results in the open literature. Batch dark fermentation of agrowastes as practiced in our work could be useful for future biorefineries that generate biohydrogen as a first step and could influence the management of this type of agricultural wastes in México and other countries and regions as well. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Production expansion continues to accelerate

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This paper reports that Saudi Arabian Oil Co. (Saudi Aramco) is continuing its accelerated Crude Oil Expansion Program initiated in 1989 that aims at achieving a 10 million bpd productive capacity by 1995. In addition to major engineering, construction and renovation work related to production expansion, Saudi Aramco drilling and workover operations have been markedly expanded. Since January 1991, rig activity has doubled. As an indication of aging of Saudi production, projects include modernizing current injection water treatment facilities, installing a new seawater injection plant on the Persian Gulf, installing dewatering facilities in a number of locations and installing a pilot gas lift project. In addition, equipment orders indicate the new discoveries south of Riyadh may also need the assistance of water injection from inception of production

  4. Effects of volatile fatty acids in biohydrogen effluent on biohythane production from palm oil mill effluent under thermophilic condition

    Directory of Open Access Journals (Sweden)

    Chonticha Mamimin

    2017-09-01

    Conclusion: Preventing the high concentration of butyric acid, and propionic acid in the hydrogenic effluent could enhance methane production in two-stage anaerobic digestion for biohythane production.

  5. Ruminal Biohydrogenation Pattern of Poly-Unsaturated Fatty Acid as Influenced by Dietary Tannin

    Directory of Open Access Journals (Sweden)

    Anuraga Jayanegara

    2013-09-01

    Full Text Available Large amounts of polyunsaturated fatty acids undergo transformation processes in the rumen through microbial biohydrogenation to form fatty acids with higher saturation degree. The respective process explains the high content of saturated fatty acids in products of ruminants and the potential risk of consumers’ health by consuming such products. Various nutritional approaches have been attempted to modulate biohydrogenation process in order to obtain healthier fatty acid profile from consumers’ perspective. The present paper is aimed to review the influence of dietary tannin, a naturally produced plant secondary compound, on the pattern of polyunsaturated fatty acids biohydrogenation occurring in the rumen. The effect of tannin on some key fatty acids involved in biohydrogenation process is presented together with the underlying mechanisms, particularly from up-to-date research results. Accordingly, different form of tannin as well as different level of the application are also discussed.

  6. Biohydrogen production from ethanol-type fermentation of molasses in an expanded granular sludge bed (EGSB) reactor

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Wan-Qian; Ren, Nan-Qi; Ding, Jie; Qu, Yuan-Yuan; Zhang, Lu-Si [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Haihe Road 204, Nangang District, Harbin, Heilongjiang 150090 (China); Wang, Xiang-Jing; Xiang, Wen-Sheng [Research Center of Life Science and Biotechnology, Northeast Agricultural University, Harbin 150030 (China); Meng, Zhao-Hui [The Architectural Design and Research Institute of Harbin Institute of Technology, Harbin 150090 (China)

    2008-10-15

    An expanded granular sludge bed (EGSB) process with granular activated carbon (GAC) was developed for fermentative hydrogen production from molasses-containing wastewater by mixed microbial cultures. No pH regulation was performed during the whole operation period. Running at the temperature of 35 C, the EGSB reactor presented a high hydrogen production ability as the hydrogen production rate (HPR) maximized at 0.71 L/L h. At the same time, the hydrogen yield (HY) peaked at 3.47 mol/mol sucrose and the maximum specific hydrogen production rate (SHPR) was found to be 3.16 mmol H{sub 2}/g VSS h. Hydrogen volume content was estimated to be 30-53% of the total biogas and the biogas was free of methane throughout the study. Dissolved fermentation products were predominated by acetate and ethanol, with smaller quantities of propionate, butyrate and valerate. It was found that high hydrogen yield was always associated with a high level of ethanol production. When the pH value and alkalinity ranged from 4.2-4.4 mg CaCO{sub 3}/L to 280-340 mg CaCO{sub 3}/L, respectively, stable ethanol-type fermentation was formed with the sum of ethanol and acetate concentration ratio of 89.1% to the total liquid products. The average attached biofilm concentration was estimated to be 17.1 g/L, which favored hydrogen production efficiently. With high biomass retention at high organic loading rate (OLR), this EGSB system showed to be a promising high-efficient bioprocess for hydrogen production from high-strength wastewater. (author)

  7. Biohydrogen production from untreated and hydrolyzed potato steam peels by the extreme thermophiles Caldicellulosiruptor saccharolyticus and Thermotoga neapolitana

    Energy Technology Data Exchange (ETDEWEB)

    Mars, Astrid E.; Veuskens, Teun; Budde, Miriam A.W.; van Doeveren, Patrick F.N.M.; Lips, Steef J.; Bakker, Robert R.; de Vrije, Truus; Claassen, Pieternel A.M. [Wageningen UR, Food and Biobased Research, P.O. Box 17, 6700 AA Wageningen (Netherlands)

    2010-08-15

    Production of hydrogen by the extreme thermophiles Caldicellulosiruptor saccharolyticus and Thermotoga neapolitana was studied in serum flasks and in pH-controlled bioreactors with glucose, and hydrolyzed and untreated potato steam peels (PSP) as carbon sources. Two types of PSP hydrolysates were used: one in which the starch in the PSP was liquefied with alpha-amylase, and one in which the liquefied starch was further hydrolyzed to glucose by amyloglucosidase. When the PSP hydrolysates or untreated PSP were added at circa 10-14 g/L of glucose units, both strains grew well and produced hydrogen with reasonable to high molar yields (2.4-3.8 moles H{sub 2}/mole glucose units), and no significant production of lactate. The hydrogen production rates and yields were similar with untreated PSP, hydrolyzed PSP, and pure glucose, showing that C. saccharolyticus and T. neapolitana are well equipped for the utilization of starch. When the concentrations of the substrates were increased, growth and hydrogen production of both strains were hampered. At substrate concentrations of circa 30-40 g/L of glucose units, the molar hydrogen yield of C. saccharolyticus was severely reduced due to the formation of high amounts of lactate, while T. neapolitana was unable to grow at all. The results showed that PSP and PSP hydrolysates are very suitable substrates for efficient fermentative hydrogen production at moderate substrate loadings. (author)

  8. Effect of Light Intensities and Atmospheric Gas Conditions on Biohydrogen Production of Microalgae Isolated from Fisheries Wastewater

    Directory of Open Access Journals (Sweden)

    Mujalin Pholchan

    2017-06-01

    Full Text Available Recently, the fishery farming industry has been developed rapidly due to increasing demand and consumption as well as the depletion of wild fish resources. Production processes in the industry usually generate large amounts of wastewater containing high nutrients, posing a threat to downstream water. However, phytoplankton removal techniques commonly used to counteract the threat, though appearing to have low efficiency, are timeconsuming and less sustainable. Microalgae are photosynthetic microorganisms that convert solar energy into hydrogen. Using the isolated algae from fish farms as a source of renewable energy production could be a promising choice for handling fisheries wastewater in a more efficient manner. However, hydrogen production processes from algae still need more studies as their efficiencies vary between algae species and growth factors. In this work, the efficiency of hydrogen production from Scenedesmus accuminatus and Arthrospira platensis harvested from fish farms under three different light intensity conditions and three atmospheric gas conditions was determined. The results showed that the best conditions for hydrogen production from both species included 24 h darkness and carbon dioxide addition. Under the atmospheric gas combination of 99% argon and 1% carbon dioxide, S. accuminatus could produce hydrogen gas as high as 0.572 mol H2/mgCh h within 12 h, while the highest hydrogen production (0.348 mol H2/mgCh h obtained from A. platensis was found under the atmospheric gas mixture of 98% argon and 2% carbon dioxide. Interestingly, S. accuminatus appeared to produce more hydrogen than A. platensis under the same conditions.

  9. Feasibility of biohydrogen production from cheese whey using a UASB reactor: Links between microbial community and reactor performance

    Energy Technology Data Exchange (ETDEWEB)

    Castello, E.; Garcia y Santos, C.; Borzacconi, L. [Chemical Engineering Institute, School of Engineering, University of the Republic, Herrera y Reissig 565, Montevideo (Uruguay); Iglesias, T.; Paolino, G.; Wenzel, J.; Etchebehere, C. [Microbiology Department, School of Science and School of Chemistry, University of the Republic, General Flores 2124, Montevideo (Uruguay)

    2009-07-15

    The present study examines the feasibility of producing hydrogen by dark fermentation using unsterilised cheese whey in a UASB reactor. A lab-scale UASB reactor was operated for more than 250 days and unsterilised whey was used as the feed. The evolution of the microbial community was studied during reactor operation using molecular biology tools (T-RFLP, 16S rRNA cloning library and FISH) and conventional microbiological techniques. The results showed that hydrogen can be produced but in low amounts. For the highest loading rate tested (20 gCOD/L.d), hydrogen production was 122 mL H{sub 2}/L.d. Maintenance of low pH (mean = 5) was insufficient to control methanogenesis; methane was produced concomitantly with hydrogen, suggesting that the methanogenic biomass adapted to the low pH conditions. Increasing the loading rate to values of 2.5 gCOD/gVSS.d favoured hydrogen production in the reactor. Microbiological studies showed the prevalence of fermentative organisms from the genera Megasphaera, Anaerotruncus, Pectinatus and Lactobacillus, which may be responsible for hydrogen production. However, the persistence of methanogenesis and the presence of other fermenters, not clearly recognised as hydrogen producers indicates that competition for the substrate may explain the low hydrogen production. (author)

  10. Effect of hydraulic retention time on biohydrogen and volatile fatty acids production during acidogenic digestion of dephenolized olive mill wastewaters

    International Nuclear Information System (INIS)

    Scoma, Alberto; Bertin, Lorenzo; Fava, Fabio

    2013-01-01

    The influence of Hydraulic Retention Time (HRT) on the performances of a recently developed biotechnological anaerobic acidogenic process fed with dephenolized Olive Mill Wastewater (OMW) was investigated. The study was carried out under mesophilic conditions in Packed Bed Biofilm Reactors (PBBRs), filled with ceramic cubes and inoculated with a characterized and acclimated acidogenic microbial consortium. The PBBRs were fed with a HRT of 7, 5, 3 or 1 day, which corresponded to Organic Loading Rates (OLRs) of about 5.5, 7.8, 12.9 and 38.8 g L −1 d −1 , respectively. A significant production of a H 2 -rich biogas was observed when shorter HRTs were applied: in particular, H 2 relative amount and productivity increased from 3% to 32% and from 0.20 to 6.10 dm 3 m −3 h −1 , respectively, by decreasing the HRT from 7 to 1 day. On the contrary, shorter HRTs turned into a lower accumulation of Volatile Fatty Acids (VFAs), whose highest amounts were found with HRTs of 7 and 5 days (about 18.4 and 19.7 g L −1 COD equivalents, respectively). The highest conversion yield of COD into VFAs (36%) was obtained with a HRT of 5 days, when VFAs represented about 78% of the effluent COD. HRT also influenced the composition of the VFA mixture: acetic, propionic and butyric acid were the most prominent VFAs, being their relative amounts higher when PBBRs were operated with shorter HRTs (up to 19, 12 and 42% of the whole mixture, respectively, when HRT was 1 day). -- Highlights: ► HRT affects the acidogenic digestion of dephenolized olive mill wastewater. ► A significant production of bioH 2 can be coupled to that of volatile fatty acids. ► Higher H 2 and lower VFA productions were obtained by shortening the HRT

  11. A pilot-scale study of biohydrogen production from distillery effluent using defined bacterial co-culture

    Energy Technology Data Exchange (ETDEWEB)

    Vatsala, T.M.; Raj, S. Mohan; Manimaran, A. (Shri AMM Murugappa Chettiar Research Centre, Photosynthesis and Energy Division, Tharamani, Chennai, India, 600)

    2008-10-15

    We evaluated the feasibility of improving the scale of hydrogen (H{sub 2}) production from sugar cane distillery effluent using co-cultures of Citrobacter freundii 01, Enterobacter aerogenes E10 and Rhodopseudomonas palustris P2 at 100 m{sup 3} scale. The culture conditions at 100 ml and 2 L scales were optimized in minimal medium and we observed that the co-culture of the above three strains enhanced H{sub 2} productivity significantly. Results at the 100 m{sup 3} scale revealed a maximum of 21.38 kg of H{sub 2}, corresponding to 10692.6 mol, which was obtained through batch method at 40 h from reducing sugar (3862.3 mol) as glucose. The average yield of H{sub 2} was 2.76 mol mol{sup -1} glucose, and the rate of H{sub 2} production was estimated as 0.53 kg/100 m{sup 3}/h. Our results demonstrate the utility of distillery effluent as a source of clean alternative energy and provide insights into treatment for industrial exploitation. (author)

  12. Continuous production of biohythane from hydrothermal liquefied cornstalk biomass via two-stage high-rate anaerobic reactors.

    Science.gov (United States)

    Si, Bu-Chun; Li, Jia-Ming; Zhu, Zhang-Bing; Zhang, Yuan-Hui; Lu, Jian-Wen; Shen, Rui-Xia; Zhang, Chong; Xing, Xin-Hui; Liu, Zhidan

    2016-01-01

    Biohythane production via two-stage fermentation is a promising direction for sustainable energy recovery from lignocellulosic biomass. However, the utilization of lignocellulosic biomass suffers from specific natural recalcitrance. Hydrothermal liquefaction (HTL) is an emerging technology for the liquefaction of biomass, but there are still several challenges for the coupling of HTL and two-stage fermentation. One particular challenge is the limited efficiency of fermentation reactors at a high solid content of the treated feedstock. Another is the conversion of potential inhibitors during fermentation. Here, we report a novel strategy for the continuous production of biohythane from cornstalk through the integration of HTL and two-stage fermentation. Cornstalk was converted to solid and liquid via HTL, and the resulting liquid could be subsequently fed into the two-stage fermentation systems. The systems consisted of two typical high-rate reactors: an upflow anaerobic sludge blanket (UASB) and a packed bed reactor (PBR). The liquid could be efficiently converted into biohythane via the UASB and PBR with a high density of microbes at a high organic loading rate. Biohydrogen production decreased from 2.34 L/L/day in UASB (1.01 L/L/day in PBR) to 0 L/L/day as the organic loading rate (OLR) of the HTL liquid products increased to 16 g/L/day. The methane production rate achieved a value of 2.53 (UASB) and 2.54 L/L/day (PBR), respectively. The energy and carbon recovery of the integrated HTL and biohythane fermentation system reached up to 79.0 and 67.7%, respectively. The fermentation inhibitors, i.e., 5-hydroxymethyl furfural (41.4-41.9% of the initial quantity detected) and furfural (74.7-85.0% of the initial quantity detected), were degraded during hydrogen fermentation. Compared with single-stage fermentation, the methane process during two-stage fermentation had a more efficient methane production rate, acetogenesis, and COD removal. The microbial distribution

  13. Particle size variations of activated carbon on biofilm formation in thermophilic biohydrogen production from palm oil mill effluent

    International Nuclear Information System (INIS)

    Jamali, Nur Syakina; Jahim, Jamaliah Md; Isahak, Wan Nor Roslam Wan; Abdul, Peer Mohamed

    2017-01-01

    Highlights: • Biofilm was developed on GAC by self-attachment immobilisation. • Effect of various micropore size of GAC was evaluated in H_2 production. • Capability of attached-biofilm to degrade cellulosic fibre in POME was evaluated. • Microbial community colonized on GAC was characterised. - Abstract: In this study, we examined the formation of thermophilic microbial biofilm by self-attachment on microbial carrier of granular activated carbon (GAC) in five different micro-pore volumes 0.31, 0.41, 0.44, 0.48, and 0.50 cm"3/g. It was found that the highest hydrogen production rate of 100.8 ± 3.7 mmol H_2/l.d and yield of 1.01 ± 0.07 mol H_2/mol sugar were obtained at 0.44 cm"3/g volume size of GAC. The cellulolytic activity of attached-biofilm was further investigated using POME as a feedstock. The results showed that in all diluted POME substrate, the total sugar consumed by the microbes was found higher than that the amount of soluble monomeric sugar present in the POME medium. It is believe that the microbial biofilm was able to hydrolyse polymeric sugar of cellulosic fibre in the POME by performing enzymatic hydrolysis into simple monomeric sugar. The isolated biofilm bacteria that subjected to 16S rRNA gene analysis presented 99% high homology to the species of Thermoanaerobacterium thermosaccharolyticum which were guaranteed to perform a cellulosic degradation activity.

  14. Biohydrogen and methane production via a two-step process using an acid pretreated native microalgae consortium.

    Science.gov (United States)

    Carrillo-Reyes, Julian; Buitrón, Germán

    2016-12-01

    A native microalgae consortium treated under thermal-acidic hydrolysis was used to produce hydrogen and methane in a two-step sequential process. Different acid concentrations were tested, generating hydrogen and methane yields of up to 45mLH 2 gVS -1 and 432mLCH 4 gVS -1 , respectively. The hydrogen production step solubilized the particulate COD (chemical oxygen demand) up to 30%, creating considerable amounts of volatile fatty acids (up to 10gCODL -1 ). It was observed that lower acid concentration presented higher hydrogen and methane production potential. The results revealed that thermal acid hydrolysis of a native microalgae consortium is a simple but effective strategy for producing hydrogen and methane in the sequential process. In addition to COD removal (50-70%), this method resulted in an energy recovery of up to 15.9kJ per g of volatile solids of microalgae biomass, one of the highest reported. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Bio-hydrolysis and bio-hydrogen production from food waste by thermophilic and hyperthermophilic anaerobic process.

    Science.gov (United States)

    Algapani, Dalal E; Qiao, Wei; Su, Min; di Pumpo, Francesca; Wandera, Simon M; Adani, Fabrizio; Dong, Renjie

    2016-09-01

    High-temperature pretreatment plays a key role in the anaerobic digestion of food waste (FW). However, the suitable temperature is not yet determined. In this work, a long-term experiment was conducted to compare hydrolysis, acidogenesis, acetogenesis, and hydrogen production at 55°C and 70°C, using real FW in CSTR reactors. The results obtained indicated that acidification was the rate-limiting step at both temperatures with similar process kinetics characterizations. However, the thermophilic pretreatment was more advantageous than the hyperthermophilic with suspended solids solubilization of 47.7% and 29.5% and total VFA vs. soluble COD ratio of 15.2% and 4.9%, for thermophilic and hyperthermophilic treatment, respectively, with a hydrolytic reaction time (HRT) of 10days and an OLR of 14kgCOD/m(3)d. Moreover, stable hydrogen yield (70.7ml-H2/gVSin) and content in off gas (58.6%) was achieved at HRT 5days, pH 5.5, and temperature of 55°C, as opposed to 70°C. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Utilization of keratin-containing biowaste to produce biohydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Balint, B.; Rakhely, G.; Kovacs, K.L. [Szeged Univ. (Hungary). Dept. of Biotechnology; Hungarian Academy of Sciences, Szeged (Hungary). Inst. of Biophysics; Bagi, Z.; Perei, K. [Szeged Univ. (Hungary). Dept. of Biotechnology; Toth, A. [Hungarian Academy of Sciences, Szeged (Hungary). Inst. of Biophysics

    2005-12-01

    A two-stage fermentation system was constructed to test and demonstrate the feasibility of biohydrogen generation from keratin-rich biowaste. We isolated a novel aerobic Bacillus strain (Bacillus licheniformis KK1) that displays outstanding keratinolytic activity. The isolated strain was employed to convert keratin-containing biowaste into a fermentation product that is rich in amino acids and peptides. The process was optimized for the second fermentation step, in which the product of keratin fermentation-supplemented with essential minerals-was metabolized by Thermococcus litoralis, an anaerobic hyperthermophilic archaeon. T. litoralis grew on the keratin hydrolysate and produced hydrogen gas as a physiological fermentation byproduct. Hyperthermophilic cells utilized the keratin hydrolysate in a similar way as their standard nutrient, i.e., bacto-peptone. The generalization of the findings to protein-rich waste treatment and production of biohydrogen is discussed and possible means of further improvements are listed. (orig.)

  17. Biohydrogen production in integrated system

    Czech Academy of Sciences Publication Activity Database

    Bélafi-Bakó, K.; Bakonyi, P.; Nemestóthy, N.; Pientka, Zbyněk

    2010-01-01

    Roč. 14, 1-3 (2010), s. 116-118 ISSN 1944-3994. [PERMEA 2009. Prague, 07.06.2009-11.06.2009] R&D Projects: GA MŠk MEB040920 Institutional research plan: CEZ:AV0Z40500505 Keywords : escherichia coli * gas separation * sodium formate Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.752, year: 2010

  18. Continuous production of polymethylpentene membranes

    Science.gov (United States)

    Epperson, B.J.; Burnett, L.J.; Helm, V.D.

    1983-11-15

    Gas separation membranes may be prepared in a continuous manner by passing a porous support which may, if so desired, be backed by a fabric through a solution of polymethylpentene dissolved in an organic solvent such as hexane. The support member is passed through the solution while one side thereof is in contact with a roller, thereby permitting only one side of the support member to be coated with the polymer. After continuously withdrawing the support member from the bath, the solvent is allowed to evaporate and the resulting membrane is recovered.

  19. Microbial electrohydrogenesis linked to dark fermentation as integrated application for enhanced biohydrogen production: A review on process characteristics, experiences and lessons.

    Science.gov (United States)

    Bakonyi, Péter; Kumar, Gopalakrishnan; Koók, László; Tóth, Gábor; Rózsenberszki, Tamás; Bélafi-Bakó, Katalin; Nemestóthy, Nándor

    2018-03-01

    Microbial electrohydrogenesis cells (MECs) are devices that have attracted significant attention from the scientific community to generate hydrogen gas electrochemically with the aid of exoelectrogen microorganisms. It has been demonstrated that MECs are capable to deal with the residual organic materials present in effluents generated along with dark fermentative hydrogen bioproduction (DF). Consequently, MECs stand as attractive post-treatment units to enhance the global H 2 yield as a part of a two-stage, integrated application (DF-MEC). In this review article, it is aimed (i) to assess results communicated in the relevant literature on cascade DF-MEC systems, (ii) describe the characteristics of each steps involved and (iii) discuss the experiences as well as the lessons in order to facilitate knowledge transfer and help the interested readers with the construction of more efficient coupled set-ups, leading eventually to the improvement of overall biohydrogen evolution performances. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Managerial implications for improving continuous production processes

    DEFF Research Database (Denmark)

    Capaci, Francesca; Vanhatalo, Erik; Bergquist, Bjarne

    2017-01-01

    . In this article we highlight SPC and DoE implementation challenges described in the literature for managers, researchers and practitioners interested in continuous production process improvement. The results may help managers support the implementation of these methods and make researchers and practitioners aware......Data analytics remains essential for process improvement and optimization. Statistical process control and design of experiments are among the most powerful process and product improvement methods available. However, continuous process environments challenge the application of these methods...... of methodological challenges in continuous process environments...

  1. Automatic continuity for homomorphisms into free products

    DEFF Research Database (Denmark)

    Slutsky, Konstantin

    2013-01-01

    A homomorphism from a completely metrizable topological group into a free product of groups whose image is not contained in a factor of the free product is shown to be continuous with respect to the discrete topology on the range. In particular, any completely metrizable group topology on a free ...

  2. Continuous fermentative hydrogen production from cheese whey wastewater under thermophilic anaerobic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Azbar, Nuri; Cetinkaya Dokgoez, F. Tuba; Keskin, Tugba; Korkmaz, Kemal S.; Syed, Hamid M. [Bioengineering Department, Faculty of Engineering, Ege University, EBILTEM, Bornova, 35100 Izmir (Turkey)

    2009-09-15

    Hydrogen (H{sub 2}) production from cheese processing wastewater via dark anaerobic fermentation was conducted using mixed microbial communities under thermophilic conditions. The effects of varying hydraulic retention time (HRT: 1, 2 and 3.5 days) and especially high organic load rates (OLR: 21, 35 and 47 g chemical oxygen demand (COD)/l/day) on biohydrogen production in a continuous stirred tank reactor were investigated. The biogas contained 5-82% (45% on average) hydrogen and the hydrogen production rate ranged from 0.3 to 7.9 l H{sub 2}/l/day (2.5 l/l/day on average). H{sub 2} yields of 22, 15 and 5 mmol/g COD (at a constant influent COD of 40 g/l) were achieved at HRT values of 3.5, 2, and 1 days, respectively. On the other hand, H{sub 2} yields were monitored to be 3, 9 and 6 mmol/g COD, for OLR values of 47, 35 and 21 g COD/l/day, when HRT was kept constant at 1 day. The total measurable volatile fatty acid concentration in the effluent (as a function of influent COD) ranged between 118 and 27,012 mg/l, which was mainly composed of acetic acid, iso-butyric acid, butyric acid, propionic acid, formate and lactate. Ethanol and acetone production was also monitored from time to time. To characterize the microbial community in the bioreactor at different HRTs, DNA in mixed liquor samples was extracted immediately for PCR amplification of 16S RNA gene using eubacterial primers corresponding to 8F and 518R. The PCR product was cloned and subjected to DNA sequencing. The sequencing results were analyzed by using MegaBlast available on NCBI website which showed 99% identity to uncultured Thermoanaerobacteriaceae bacterium. (author)

  3. Ruminal microbe of biohydrogenation of trans-vaccenic acid to stearic acid in vitro

    Directory of Open Access Journals (Sweden)

    Li Dan

    2012-02-01

    Full Text Available Abstract Background Optimization of the unsaturated fatty acid composition of ruminant milk and meat is desirable. Alteration of the milk and fatty acid profile was previously attempted by the management of ruminal microbial biohydrogenation. The aim of this study was to identify the group of ruminal trans-vaccenic acid (trans-11 C18:1, t-VA hydrogenating bacteria by combining enrichment studies in vitro. Methods The enrichment culture growing on t-VA was obtained by successive transfers in medium containing t-VA. Fatty acids were detected by gas chromatograph and changes in the microbial composition during enrichment were analyzed by denaturing gradient gel electrophoresis (DGGE. Prominent DGGE bands of the enrichment cultures were identified by 16S rRNA gene sequencing. Results The growth of ruminal t-VA hydrogenating bacteria was monitored through the process of culture transfer according to the accumulation of stearic acid (C18:0, SA and ratio of the substrate (t-VA transformed to the product (SA. A significant part of the retrieved 16S rRNA gene sequences was most similar to those of uncultured bacteria. Bacteria corresponding to predominant DGGE bands in t-VA enrichment cultures clustered with t-VA biohydrogenated bacteria within Group B. Conclusions This study provides more insight into the pathway of biohydrogenation. It also may be important to control the production of t-VA, which has metabolic and physiological benefits, through management of ruminal biohydrogenation bacterium.

  4. Exploitation of algal-bacterial associations in a two-stage biohydrogen and biogas generation process.

    Science.gov (United States)

    Wirth, Roland; Lakatos, Gergely; Maróti, Gergely; Bagi, Zoltán; Minárovics, János; Nagy, Katalin; Kondorosi, Éva; Rákhely, Gábor; Kovács, Kornél L

    2015-01-01

    The growing concern regarding the use of agricultural land for the production of biomass for food/feed or energy is dictating the search for alternative biomass sources. Photosynthetic microorganisms grown on marginal or deserted land present a promising alternative to the cultivation of energy plants and thereby may dampen the 'food or fuel' dispute. Microalgae offer diverse utilization routes. A two-stage energetic utilization, using a natural mixed population of algae (Chlamydomonas sp. and Scenedesmus sp.) and mutualistic bacteria (primarily Rhizobium sp.), was tested for coupled biohydrogen and biogas production. The microalgal-bacterial biomass generated hydrogen without sulfur deprivation. Algal hydrogen production in the mixed population started earlier but lasted for a shorter period relative to the benchmark approach. The residual biomass after hydrogen production was used for biogas generation and was compared with the biogas production from maize silage. The gas evolved from the microbial biomass was enriched in methane, but the specific gas production was lower than that of maize silage. Sustainable biogas production from the microbial biomass proceeded without noticeable difficulties in continuously stirred fed-batch laboratory-size reactors for an extended period of time. Co-fermentation of the microbial biomass and maize silage improved the biogas production: The metagenomic results indicated that pronounced changes took place in the domain Bacteria, primarily due to the introduction of a considerable bacterial biomass into the system with the substrate; this effect was partially compensated in the case of co-fermentation. The bacteria living in syntrophy with the algae apparently persisted in the anaerobic reactor and predominated in the bacterial population. The Archaea community remained virtually unaffected by the changes in the substrate biomass composition. Through elimination of cost- and labor-demanding sulfur deprivation, sustainable

  5. Layerless fabrication with continuous liquid interface production.

    Science.gov (United States)

    Janusziewicz, Rima; Tumbleston, John R; Quintanilla, Adam L; Mecham, Sue J; DeSimone, Joseph M

    2016-10-18

    Despite the increasing popularity of 3D printing, also known as additive manufacturing (AM), the technique has not developed beyond the realm of rapid prototyping. This confinement of the field can be attributed to the inherent flaws of layer-by-layer printing and, in particular, anisotropic mechanical properties that depend on print direction, visible by the staircasing surface finish effect. Continuous liquid interface production (CLIP) is an alternative approach to AM that capitalizes on the fundamental principle of oxygen-inhibited photopolymerization to generate a continual liquid interface of uncured resin between the growing part and the exposure window. This interface eliminates the necessity of an iterative layer-by-layer process, allowing for continuous production. Herein we report the advantages of continuous production, specifically the fabrication of layerless parts. These advantages enable the fabrication of large overhangs without the use of supports, reduction of the staircasing effect without compromising fabrication time, and isotropic mechanical properties. Combined, these advantages result in multiple indicators of layerless and monolithic fabrication using CLIP technology.

  6. Effect of dilution and L-malic acid addition on bio-hydrogen production with Rhodopseudomonas palustris from effluent of an acidogenic anaerobic reactor

    International Nuclear Information System (INIS)

    Azbar, N.; Tuba, F.; Dokgoz, C.

    2009-01-01

    In this study, H 2 was produced in a two-stage biological process: I) first stage; the dark fermentation of cheese whey wastewater, which is rich in lactose, by mixed anaerobic culture grown at thermophilic temperature in a continuously running fermentor and ii) second stage; the photo-fermentation of the residual medium by R. palustris strain (DSM 127) at 31 o C under illumination of 150 W in batch mode, respectively. In the first part of the study, the effluent from the dark fermentation reactor was used either as it is (no dilution) or after dilution with distilled water at varying ratios such as 1/2 , 1/5, 1/10 (1 volume effluent/5 volume distilled water) before used in photo-fermentation experiments. In the second part of the study, L-malic acid at varying amounts was added into the hydrogen production medium in order to have L-malic acid concentrations ranging from 0 to 4 g/l. Non-diluted and pre-diluted mediums with or without L-malic acid addition were also tested for comparison purpose (as controls). Prior to the hydrogen production experiments, all samples were subjected to pH adjustment, (pH 6.7) and sterilized by autoclave at 121 o C for 15 min. In regards to the experiments in which the effect of dilution of the effluent from dark fermentation was studied, it was observed that dilution of the effluent from dark fermentation resulted in much better hydrogen productions. Among the dilution rates used, the experiments operated with 1/5 dilution ratio produced the best hydrogen production (241 ml H 2 / g COD fed ). On the other hand, it was seen that the mixing the effluent with L-malic acid (0 - 4 g/l) at increasing ratios (studied from 0% L-malic acid up to 100% by volume in the mixture) had further positive effect and improved the hydrogen production. The bioreactors containing only L-malic acid media resulted in the best hydrogen production (438 ml H 2 / g COD fed ). It was found that, undiluted raw cheese whey wastewater effluent from dark hydrogen

  7. Effect of dilution and L-malic acid addition on bio-hydrogen production with Rhodopseudomonas palustris from effluent of an acidogenic anaerobic reactor

    Energy Technology Data Exchange (ETDEWEB)

    Azbar, N.; Tuba, F.; Dokgoz, C. [Bioengineering Dept., Faculty of Engineering, Ege Univ., Izmir (Turkey)], E-mail: nuri.azbar@ege.edu.tr

    2009-07-01

    In this study, H{sub 2} was produced in a two-stage biological process: I) first stage; the dark fermentation of cheese whey wastewater, which is rich in lactose, by mixed anaerobic culture grown at thermophilic temperature in a continuously running fermentor and ii) second stage; the photo-fermentation of the residual medium by R. palustris strain (DSM 127) at 31{sup o}C under illumination of 150 W in batch mode, respectively. In the first part of the study, the effluent from the dark fermentation reactor was used either as it is (no dilution) or after dilution with distilled water at varying ratios such as 1/2 , 1/5, 1/10 (1 volume effluent/5 volume distilled water) before used in photo-fermentation experiments. In the second part of the study, L-malic acid at varying amounts was added into the hydrogen production medium in order to have L-malic acid concentrations ranging from 0 to 4 g/l. Non-diluted and pre-diluted mediums with or without L-malic acid addition were also tested for comparison purpose (as controls). Prior to the hydrogen production experiments, all samples were subjected to pH adjustment, (pH 6.7) and sterilized by autoclave at 121{sup o}C for 15 min. In regards to the experiments in which the effect of dilution of the effluent from dark fermentation was studied, it was observed that dilution of the effluent from dark fermentation resulted in much better hydrogen productions. Among the dilution rates used, the experiments operated with 1/5 dilution ratio produced the best hydrogen production (241 ml H{sub 2}/ g COD{sub fed}). On the other hand, it was seen that the mixing the effluent with L-malic acid (0 - 4 g/l) at increasing ratios (studied from 0% L-malic acid up to 100% by volume in the mixture) had further positive effect and improved the hydrogen production. The bioreactors containing only L-malic acid media resulted in the best hydrogen production (438 ml H{sub 2} / g COD{sub fed}). It was found that, undiluted raw cheese whey wastewater

  8. Operational Aspects of Continuous Pharmaceutical Production

    DEFF Research Database (Denmark)

    Mitic, Aleksandar

    Introduction of the Process Analytical Technolo gy (PAT) Initiative, the Quality by Design (QbD) approach and the Continuous Improvement (CI) methodology/philosophy is considered as a huge milestone in the modern pharmaceutical indust ry. The above concepts, when applied to a pharmaceutical...... satisfaction of the demands defined by the PA T Initiative. This approach could be considered as establishing a Lean Production System (LPS) whic h is usually supported with tools associated with Process Intensifaction (PI) a nd Process Optimization (PO). Development of continuous processes is often c onnected...... tools, such as microwave assisted organic synthesis (MAOS), ultrasounds, meso-scale flow chemistry and microprocess technology. Furthermore, developmen t of chemical catalysts and enzymes enabled further acceleration of some chemical reactions that were known as very slow or impossible to be performed...

  9. Continuous hydrogen production from starch by fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Yasuda, Keigo; Tanisho, Shigeharu [Yokohama National Univ. (Japan)

    2010-07-01

    This study was investigated the effect of hydraulic retention time (HRT) on hydrogen production rate, hydrogen yield and the production rate of volatile fatty acid. The experiment was performed in a continuous stirred tank reactor (CSTR) with a working volume of 1 L by using a Clostridium sp. The temperature of the CSTR was regulated 37 C. The pH was controlled 6.0 by the addition of 3 M of NaOH solution. Starch was used as the carbon source with the concentration of 30 g L{sup -1}. Hydrogen production rate increased from 0.9 L-H{sub 2} L-culture{sup -1} h{sup -1} to 3.2 L-H{sub 2} L-culture{sup -1} h{sup -1} along with the decrease of HRT from 9 h to 1.5 h. Hydrogen yield decreased at low HRT. The major volatile fatty acids are acetic acid, butyric acid and lactic acid. The production rates of acetic acid and butyric acid increased along with the decrease of HRT. On the other hand, the rate of lactic acid was low at high HRT while it increased at HRT 1.5 h. The increase of the production rate of lactic acid suggested one of the reasons that hydrogen yield decreased. (orig.)

  10. Rumen Biohydrogenation and Microbial Community Changes Upon Early Life Supplementation of 22:6n-3 Enriched Microalgae to Goats

    Directory of Open Access Journals (Sweden)

    Lore Dewanckele

    2018-03-01

    Full Text Available Dietary supplementation of docosahexaenoic acid (DHA-enriched products inhibits the final step of biohydrogenation in the adult rumen, resulting in the accumulation of 18:1 isomers, particularly of trans(t-11 18:1. Occasionally, a shift toward the formation of t10 intermediates at the expense of t11 intermediates can be triggered. However, whether similar impact would occur when supplementing DHA-enriched products during pregnancy or early life remains unknown. Therefore, the current in vivo study aimed to investigate the effect of a nutritional intervention with DHA in the early life of goat kids on rumen biohydrogenation and microbial community. Delivery of DHA was achieved by supplementing DHA-enriched microalgae (DHA Gold either to the maternal diet during pregnancy (prenatal or to the diet of the young offspring (postnatal. At the age of 12 weeks, rumen fluid was sampled for analysis of long-chain fatty acids and microbial community based on bacterial 16S rRNA amplicon sequencing. Postnatal supplementation with DHA-enriched microalgae inhibited the final biohydrogenation step, as observed in adult animals. This resulted particularly in increased ruminal proportions of t11 18:1 rather than a shift to t10 intermediates, suggesting that both young and adult goats might be less prone to dietary induced shifts toward the formation of t10 intermediates, in comparison with cows. Although Butyrivibrio species have been identified as the most important biohydrogenating bacteria, this genus was more abundant when complete biohydrogenation, i.e. 18:0 formation, was inhibited. Blautia abundance was positively correlated with 18:0 accumulation, whereas Lactobacillus spp. Dialister spp. and Bifidobacterium spp. were more abundant in situations with greater t10 accumulation. Extensive comparisons made between current results and literature data indicate that current associations between biohydrogenation intermediates and rumen bacteria in young goats

  11. Re-fermentation of washed spent solids from batch hydrogenogenic fermentation for additional production of biohydrogen from the organic fraction of municipal solid waste.

    Science.gov (United States)

    Muñoz-Páez, Karla M; Ríos-Leal, Elvira; Valdez-Vazquez, Idania; Rinderknecht-Seijas, Noemí; Poggi-Varaldo, Héctor M

    2012-03-01

    In the first batch solid substrate anaerobic hydrogenogenic fermentation with intermittent venting (SSAHF-IV) of the organic fraction of municipal solid waste (OFMSW), a cumulative production of 16.6 mmol H(2)/reactor was obtained. Releases of hydrogen partial pressure first by intermittent venting and afterward by flushing headspace of reactors with inert gas N(2) allowed for further hydrogen production in a second to fourth incubation cycle, with no new inoculum nor substrate nor inhibitor added. After the fourth cycle, no more H(2) could be harvested. Interestingly, accumulated hydrogen in 4 cycles was 100% higher than that produced in the first cycle alone. At the end of incubation, partial pressure of H(2) was near zero whereas high concentrations of organic acids and solvents remained in the spent solids. So, since approximate mass balances indicated that there was still a moderate amount of biodegradable matter in the spent solids we hypothesized that the organic metabolites imposed some kind of inhibition on further fermentation of digestates. Spent solids were washed to eliminate organic metabolites and they were used in a second SSAHF-IV. Two more cycles of H(2) production were obtained, with a cumulative production of ca. 2.4 mmol H(2)/mini-reactor. As a conclusion, washing of spent solids of a previous SSAHF-IV allowed for an increase of hydrogen production by 15% in a second run of SSAHF-IV, leading to the validation of our hypothesis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Production of hydrogen in a granular sludge-based anaerobic continuous stirred tank reactor

    Energy Technology Data Exchange (ETDEWEB)

    Show, Kuan-Yeow [Faculty of Engineering and Science, University of Tunku Abdul Rahman, 53300 Setapak, Kuala Lumpur (Malaysia); Zhang, Zhen-Peng; Tay, Joo-Hwa [School of Civil and Environmental Engineering, Nanyang Technological University, 639798 (Singapore); Institute of Environmental Science and Engineering, Nanyang Technological University, 637723 (Singapore); Tee Liang, David [Institute of Environmental Science and Engineering, Nanyang Technological University, 637723 (Singapore); Lee, Duu-Jong [Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan, RO (China); Jiang, Wen-Ju [Department of Environmental Science and Engineering, Sichuan University, Chengdu 610065 (China)

    2007-12-15

    An investigation on biohydrogen production was conducted in a granular sludge-based continuous stirred tank reactor (CSTR). The reactor performance was assessed at five different glucose concentrations of 2.5, 5, 10, 20 and 40 g/L and four hydraulic retention times (HRTs) of 0.25, 0.5, 1 and 2 h, resulting in the organic loading rates (OLRs) ranged between 2.5 and 20 g-glucose/L h. Carbon flow was traced by analyzing the composition of gaseous and soluble metabolites as well as the cell yield. Butyrate, acetate and ethanol were found to be the major soluble metabolite products in the biochemical synthesis of hydrogen. Carbon balance analysis showed that more than half of the glucose carbon was converted into unidentified soluble products at an OLR of 2.5 g-glucose/L h. It was found that high hydrogen yields corresponded to a sludge loading rate in between 0.6 and 0.8 g-glucose/g-VSS h. Substantial suppression in hydrogen yield was noted as the sludge loading rate fell beyond the optimum range. It is deduced that decreasing the sludge loading rate induced the metabolic shift of biochemical reactions at an OLR of 2.5 g-glucose/L h, which resulted in a substantial reduction in hydrogen yield to 0.36-0.41 mol-H{sub 2}/mol-glucose. Optimal operation conditions for peak hydrogen yield (1.84 mol-H{sub 2}/mol-glucose) and hydrogen production rate (3.26 L/L h) were achieved at an OLR of 20 g-glucose/L h, which corresponded to an HRT of 0.5 h and an influent glucose concentration of 10 g/L. Influence of HRT and substrate concentration on the reactor performance was interrelated and the adverse impact on hydrogen production was noted as substrate concentration was higher than 20 g/L or HRT was shorter than 0.5 h. The experimental study indicated that a higher OLR derived from appropriate HRTs and substrate concentrations was desirable for hydrogen production in such a granule-based CSTR. (author)

  13. Mitigation of the inhibitory effect of soap by magnesium salt treatment of crude glycerol--a novel approach for enhanced biohydrogen production from the biodiesel industry waste.

    Science.gov (United States)

    Sarma, Saurabh Jyoti; Brar, Satinder Kaur; Le Bihan, Yann; Buelna, Gerardo; Soccol, Carlos Ricardo

    2014-01-01

    Owing to its inhibitory effect on microbial growth, soap present in crude glycerol (CG) is a concern in biological valorization of the biodiesel manufacturing waste. By salting out strategy, up to 42% of the soap has been removed and the approach has beneficial effect on H2 production; however, removal of more than 7% of the soap was found to be inhibitory. Actually, soap is utilized as a co-substrate and due to removal; the carbon-nitrogen ratio of the medium might have decreased to reduce the production. Alternatively, without changing the carbon-nitrogen ratio of CG, MgSO4 treatment can convert the soap to its inactive form (scum). The approach was found to increase the H2 production rate (33.82%), cumulative H2 production (34.70%) as well as glycerol utilization (nearly 2.5-folds). Additionally, the treatment can increase the Mg (a nutrient) content of the medium from 0.57 ppm to 201.92 ppm. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Bioaugmentation of Lactobacillus delbrueckii ssp. bulgaricus TISTR 895 to enhance bio-hydrogen production of Rhodobacter sphaeroides KKU-PS5.

    Science.gov (United States)

    Laocharoen, Sucheera; Reungsang, Alissara; Plangklang, Pensri

    2015-01-01

    Bioaugmentation or an addition of the desired microorganisms or specialized microbial strains into the anaerobic digesters can enhance the performance of microbial community in the hydrogen production process. Most of the studies focused on a bioaugmentation of native microorganisms capable of producing hydrogen with the dark-fermentative hydrogen producers while information on bioaugmentation of purple non-sulfur photosynthetic bacteria (PNSB) with lactic acid-producing bacteria (LAB) is still limited. In our study, bioaugmentation of Rhodobacter sphaeroides KKU-PS5 with Lactobacillus delbrueckii ssp. bulgaricus TISTR 895 was conducted as a method to produce hydrogen. Unfortunately, even though well-characterized microorganisms were used in the fermentation system, a cultivation of two different organisms in the same bioreactor was still difficult because of the differences in their metabolic types, optimal conditions, and nutritional requirements. Therefore, evaluation of the physical and chemical factors affecting hydrogen production of PNSB augmented with LAB was conducted using a full factorial design followed by response surface methodology (RSM) with central composite design (CCD). A suitable LAB/PNSB ratio and initial cell concentration were found to be 1/12 (w/w) and 0.15 g/L, respectively. The optimal initial pH, light intensity, and Mo concentration obtained from RSM with CCD were 7.92, 8.37 klux and 0.44 mg/L, respectively. Under these optimal conditions, a cumulative hydrogen production of 3396 ± 66 mL H2/L, a hydrogen production rate (HPR) of 9.1 ± 0.2 mL H2/L h, and a hydrogen yield (HY) of 9.65 ± 0.23 mol H2/mol glucose were obtained. KKU-PS5 augmented with TISTR 895 produced hydrogen from glucose at a relatively high HY, 9.65 ± 0.23 mol H2/mol glucose, i.e., 80 % of the theoretical yield. The ratio of the strains TISTR 895/KKU-PS5 and their initial cell concentrations affected the rate of lactic acid production and its

  15. Enhanced biohydrogen production from oat straw co-digested with cow dung / sewage sludge by combined aerobic digestion and anaerobic fermentation

    Directory of Open Access Journals (Sweden)

    Loretta Li

    2016-03-01

    Full Text Available Hydrogen was produced from oat straw by combined aerobic and anaerobic fermentation with fungi and cow dung. With aerobic pre-digestion, the maximum hydrogen production rate reached 133 ml/g volatile suspended solids per hour. The maximum hydrogen yield was 71.5 ml/g straw in 6 days by biological process. The lignocellulosic conversion of oak-straw waste was 39%, with the complex component converting 68% of the hemi-cellulose and 61% of the cellulose, but only 34% of lignin conversion. Aerobic pre-digestion by Trichoderma viride and Saccharomyces cerevisiae was significantly effective for lignin degradation.  Combining aerobic and anaerobic fermentation is a promising low-cost efficient and environmentally friendly method, compared with hydrogen fermentation, not only for hydrogen production, but also for converting straw biomass.

  16. The influence of chicken eggshell powder as a buffer on biohydrogen production from rotten orange (Citrus nobilis var. microcarpa) with immobilized mixed culture

    Science.gov (United States)

    Damayanti, Astrilia; Sarto, Syamsiah, Siti; Sediawan, Wahyudi B.

    2017-06-01

    This research observed the influence of chicken eggshell on hydrogen production from anaerobic fermentation of rotten orange (Citrus nobilis var. microcarpa) using batch method at 36 °C and pH 7. Fermentation material were varied in several types, the first type was meat and peel of oranges with VS of 59.152 g.L-1 in A, B, C, and D compositions. The second type was orange meat added with peel (OMP) with VS of 36.852 g.L-1. The immobilized ingredients used in the experiment consisted of 2 % (w/v) alginate and active carbon with the ratio of 1:1. 3.2 g chicken eggshell powder was added to the first type of material (substrates A, B, C, and D). Results showed that pH during fermentation process using chicken eggshell as a buffer was constant at 5.5; however, without the use of chicken eggshell, the pH decreased to 3.8 and increased slightly before it stayed stable at 4.0. The total amount of gas produced in sample using the chicken eggshell was 46,35 mL.mg VS-1 and in sample produced without the eggshell, it was 3,4 mL.mg VS-1. The production of hydrogen in substrate that used chicken eggshell was 1,276 mL.gVS-1 in average on the first day. Meanwhile, for the substrate with no addition of chicken eggshell, the average production of hydrogen was 0,163 mL.gVS-1. The reduction of volatile solid (VS) in sample that used chicken eggshell was 24 %, while in sample produced without addition of chicken eggshell, the reduction was 12 %. The liquid compounds (VFA) produced in the fermentation using chicken eggshell were acetic acid and butyric acid. Meanwhile, without addition of chicken eggshell, the products were acetic acid, butyric acid, and propionic acid. This study shows that addition of chicken eggshell as a buffer effectively contributed to hydrogen production during fermentation of rotten oranges.

  17. An integrated biohydrogen refinery: synergy of photofermentation, extractive fermentation and hydrothermal hydrolysis of food wastes.

    Science.gov (United States)

    Redwood, Mark D; Orozco, Rafael L; Majewski, Artur J; Macaskie, Lynne E

    2012-09-01

    An Integrated Biohydrogen Refinery (IBHR) and experimental net energy analysis are reported. The IBHR converts biomass to electricity using hydrothermal hydrolysis, extractive biohydrogen fermentation and photobiological hydrogen fermentation for electricity generation in a fuel cell. An extractive fermentation, developed previously, is applied to waste-derived substrates following hydrothermal pre-treatment, achieving 83-99% biowaste destruction. The selective separation of organic acids from waste-fed fermentations provided suitable substrate for photofermentative hydrogen production, which enhanced the gross energy generation up to 11-fold. Therefore, electrodialysis provides the key link in an IBHR for 'waste to energy'. The IBHR compares favourably to 'renewables' (photovoltaics, on-shore wind, crop-derived biofuels) and also emerging biotechnological options (microbial electrolysis) and anaerobic digestion. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Simulation of continuous cast steel product solidification

    Directory of Open Access Journals (Sweden)

    Ardelean, E.

    2007-06-01

    Full Text Available Primary cooling – inside the tundish – has a great impact over the thickness of the solidified steel crust. If on exiting the tundish the crust is too thin, it can punch and break, as a result of the ferrostatic pressure exerted from the inside by the liquid steel as well as because of the weight of the molten steel. The parameters that influence the amount of dissipated heat depend on the cooling water flow of the tundish, on the pressure and temperature of the cooling water but also on the overheating of the continuously cast steel. The secondary cooling takes place at the exit of the semi-finished product from the tundish, when the solidification is supposed to take place all along the cross section of the strand. In order to achieve it, in addition to a correctly managed primary cooling, it is necessary to obtain the proper correlation of the factors that influence the secondary cooling as well: the water flow rate long the three zones of the installation and its pressure in the secondary circuit. All these have in view a proper solidification length; an intense cooling can generate cracks due to the thermal stress, while a too slow cooling can generate a partial solidification of the strand up to the cropping machine area. The paper presents a mathematical simulation of the continuously cast steel solidification.

    El enfriamiento primario del cristalizador tiene una gran importancia sobre el espesor de la costra de acero solidificado. Si al salir del cristalizador, esta costra es demasiado sutil, bajo la acción de la presión ferro estática ejercitada por el acero líquido del interior y gracias el peso propio del hilo, ésta, puede perforar resultando su rompimiento. Los parámetros que influenyen sobre la cantidad de calor cedida dependen del agua de enfriamiento del catalizador, de la presión y de la temperatura de agua de enfriamiento, pero también del sobrecalentamiento del acero fundido continuamente. A la salida del

  19. Learning barriers in continuous product innovation

    NARCIS (Netherlands)

    Gieskes, J.F.B.; Hyland, Paul W.

    2003-01-01

    In today's dynamic and turbulent environment companies are required to increase their effectiveness and efficiency, exploit synergy and learn product innovation processes in order to build competitive advantage. To be able to stimulate and facilitate learning in product innovation, it is necessary

  20. Continuous downstream processing for high value biological products: A Review.

    Science.gov (United States)

    Zydney, Andrew L

    2016-03-01

    There is growing interest in the possibility of developing truly continuous processes for the large-scale production of high value biological products. Continuous processing has the potential to provide significant reductions in cost and facility size while improving product quality and facilitating the design of flexible multi-product manufacturing facilities. This paper reviews the current state-of-the-art in separations technology suitable for continuous downstream bioprocessing, focusing on unit operations that would be most appropriate for the production of secreted proteins like monoclonal antibodies. This includes cell separation/recycle from the perfusion bioreactor, initial product recovery (capture), product purification (polishing), and formulation. Of particular importance are the available options, and alternatives, for continuous chromatographic separations. Although there are still significant challenges in developing integrated continuous bioprocesses, recent technological advances have provided process developers with a number of attractive options for development of truly continuous bioprocessing operations. © 2015 Wiley Periodicals, Inc.

  1. Ionic liquid-impregnated activated carbon for biohydrogen purification in an adsorption unit

    Science.gov (United States)

    Yusuf, N. Y.; Masdar, M. S.; Isahak, W. N. R. W.; Nordin, D.; Husaini, T.; Majlan, E. H.; Rejab, S. A. M.; Chew, C. L.

    2017-06-01

    Biological methods for hydrogen production (biohydrogen) are known as energy intensive and can be operated at ambient temperature and pressure; however, consecutive productions such as purification and separation processes still remain challenging in the industry. Various techniques are used to purify and separate hydrogen. These techniques include the use of sorbents/solvents, membranes and cryogenic distillation. In this study, carbon dioxide (CO2) was purified and separated from biohydrogen to produce high purity hydrogen gas. CO2 capture was studied using the activated carbon (AC) modified with the ionic liquid (IL) choline chloride as adsorbent. The physical and chemical properties of the adsorbents were characterized through XRD, FTIR, SEM-EDX, TGA, and BET analyses. The effects of IL loading, flow rate, temperature, and gas mixture were also investigated based on the absorption and desorption of CO2. The CO2 level in the biohydrogen composition was analyzed using a CO2 gas analyzer. The SEM image indicated that the IL homogeneously covered the AC surface. High IL dispersion inlet enhanced the capability of the adsorbent to capture CO2 gas. The thermal stability and presence of the functionalized group of ILs on AC were analyzed by TGA and FTIR techniques, respectively. CO2 adsorption experiments were conducted using a 1 L adsorber unit. Hence, adsorption technologies exhibit potential for biohydrogen purification and mainly affected by adsorbent ability and operating parameters. This research presents an improved biohydrogen technique based on adsorption technology with novel adsorbents. Two different types of commercial CO2 adsorbents were used in the experiment. Results show that the IL/AC exhibited properties suitable for CO2 adsorption. The IL/AC sample presented a high CO2 uptake of 30 wt. % IL when treated at 30 °C for 6 h under a flow rate of 1 L/min. The presence of IL increased the selectivity of CO2 removal during the adsorption process. This IL

  2. Continuous saccharification and fermentation in alcohol production

    Energy Technology Data Exchange (ETDEWEB)

    Veselov, I Ya; Gracheva, I M; Mikhailova, L E; Babaeva, S A; Ustinnikov, B A

    1968-01-01

    Submerged cultures of Aspergillus niger NRRL 337 and A. batatae 61, or a mixture of submerged A. niger culture with a surface culture of A. oryzae Kc are used for fermentations and compared with the usual barley malt procedure. The latter yields 71% maltose and 24 to 28% glucose, wherease the fungal procedure gives 14 to 21% maltose and 80 to 85% glucose in a continuous mashing-fermentation process with barley. The fungal method gives a higher degree of fermentation for sugars and dextrins and a lower content of total and high-molecular-weight residual dextrins. The amounts of propanol PrOH and iso-BuOH isobutyl alcohol are almost equal, whereas the amount of isoamylalcohol is lower in fungal fermentations.

  3. The effect of diet supplemented with vegetable oils and/or monensin on the vaccenic acid production in continuous culture fermenters

    Directory of Open Access Journals (Sweden)

    Mostafa Sayed A. Khattab

    2015-12-01

    Full Text Available Studies have shown that supplementing ruminant diets with vegetable oils modulated the rumen biohydrogenation and increased polyunsaturated fatty acid in their products. These positive values are often accompanied by a marginal loss of supplemented unsaturated fatty acids and rise in the concentrations of saturated fatty acids. This study were carried out mainly to investigate the effect of supplementing diets with sunflower oil, olive oil with or without monensin on the production and accumulation of vaccenic acid (VA in continuous culture fermenters as a long term in vitro rumen simulation technique. Eight dual-flow continuous culture fermenters were used in an 8 replication experiment lasted 10 days each (first 7 days for adaptation and last 3 days for samples collection. Supplementing diets with plant oils and monensin in the present experiment increased VA and conjugated linoleic acids (P > 0.05 in ruminal cultures. The results suggest that supplementing diets with both olive oil and sunflower oil and monensin increased VA accumulation compared to plant oils supplemented alone without affecting the rumen dry matter and organic matter digestibility.

  4. Analysis of energy consumption and CO{sub 2} emissions of the life cycle of bio-hydrogen applied to the Portuguese road transportation sector

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Ana Filipa; Baptista, Patricia; Silva, Carla [IDMEC (Portugal). Dept. of Mechanical Engineering

    2010-07-01

    In this work the main objective is to analyze energy consumption and CO{sub 2} emissions of biohydrogen for use in the transportation sector in Portugal. A life cycle assessment will be performed in order to evaluate bio-hydrogen pathways, having biodiesel and conventional fossil diesel as reference. The pathways were production of feedstock, pre-treatment, treatment, compression, distribution and applications. For the well-to-tank analysis the SimaPro 7.1 software and excel tools are used. This study includes not only a well-to-tank analysis but also a tank-to-wheel analysis (using ADVISOR software) estimating hydrogen consumption and electricity consumption of a fuel cell hybrid and a plug-in hybrid. Several bio-hydrogen feedstocks to produce hydrogen through fermentation processes will be considered: potato peels. (orig.)

  5. Mixing and settling in continuous metal production

    International Nuclear Information System (INIS)

    Richter, H.J.; Laaspere, J.T.; Fitzpatrick, J.M.

    1993-01-01

    Modern metallurgical processes produce metal from ore in a single converter operated in horizontal mode to permit staging of bath and oxygen potential by utilizing bottom-blowing of oxygen and fuel. The submerged injectors must create sufficient turbulence to provide excellent gas-liquid contact in order to maximize heat and mass transfer in the bath, but this turbulence must be selectively localized so as to provide adequate phase separation zones of metal and slag between the active turbulent zones. It is important to know the behavior of gas and liquids in the bubble plume, the nature and paths of liquids and entrainment into the plume, and separation phenomena including travel and behavior in the settling zones. Such knowledge is of fundamental value in designing reactors for continuous direct metal making. In this work the mixing caused by submerged injection of gas into a bath simulating a converter and subsequent phase separation of two immiscible liquids representing slag and metal respectively, are being studied experimentally and analytically. First results of experiments and of the numerical analysis are presented

  6. Temperature and duration of heating of sunflower oil affect ruminal biohydrogenation of linoleic acid in vitro

    OpenAIRE

    Privé , Florence; Combes, Sylvie; Cauquil, Laurent; Farizon, Yves; Enjalbert, Francis; Troegeler-Meynadier, Annabelle

    2010-01-01

    Sunflower oil heated at 110 or 150°C for 1, 3, or 6 h was incubated with ruminal content in order to investigate the effects of temperature and duration of heating of oil on the ruminal biohydrogenation of linoleic acid in vitro. When increased, these 2 parameters acted together to decrease the disappearance of linoleic acid in the media by inhibiting the isomerization of linoleic acid, which led to a decrease in conjugated linoleic acids and trans-C18:1 production. Nevertheless, trans-10 iso...

  7. Potential of Continuous Manufacturing for Liposomal Drug Products.

    Science.gov (United States)

    Worsham, Robert D; Thomas, Vaughan; Farid, Suzanne S

    2018-05-21

    Over the last several years, continuous manufacturing of pharmaceuticals has evolved from bulk APIs and solid oral dosages into the more complex realm of biologics. The development of continuous downstream processing techniques has allowed biologics manufacturing to realize the benefits (e.g. improved economics, more consistent quality) that come with continuous processing. If relevant processing techniques and principles are selected, the opportunity arises to develop continuous manufacturing designs for additional pharmaceutical products including liposomal drug formulations. Liposome manufacturing has some inherent aspects that make it favorable for a continuous process. Other aspects such as formulation refinement, materials of construction, and aseptic processing need development, but present an achievable challenge. This paper reviews the current state of continuous manufacturing technology applicable to liposomal drug product manufacturing and an assessment of the challenges and potential of this application. This article is protected by copyright. All rights reserved.

  8. A continuous-time control model on production planning network ...

    African Journals Online (AJOL)

    A continuous-time control model on production planning network. DEA Omorogbe, MIU Okunsebor. Abstract. In this paper, we give a slightly detailed review of Graves and Hollywood model on constant inventory tactical planning model for a job shop. The limitations of this model are pointed out and a continuous time ...

  9. Moving from batch towards continuous organic‐chemical pharmaceutical production

    DEFF Research Database (Denmark)

    Cervera Padrell, Albert Emili

    process understanding. Developing a process within a more flexible design space based on sound engineering judgment potentially allows process optimization once the product has already been approved. Micro‐ and mini‐chemical systems have been envisaged as the optimal scale for pharmaceutical production...... are the highest benefits found? How can a continuous process be designed and implemented? Are continuous processes compatible with slow reactions? Do they allow problem free processing of solid particles? What is the cost needed to implement a continuous process? This PhD thesis tries to answer some of those...... questions through the development of a systematic framework that takes advantage of continuous processing technologies and process systems engineering for the efficient design of continuous pharmaceutical processes. The framework consists of a step‐by‐step procedure that guides the user from drug discovery...

  10. Design of Continuous Reactor Systems for API Production

    DEFF Research Database (Denmark)

    Pedersen, Michael Jønch

    -scale production equipment enabled complete replacement of the existing batch production of this intermediate. The crowning achievement in this work was the realization of continuous laboratory reactor setups capable of manufacturing the entire GMP portion of the synthesis of melitracen HCl at H. Lundbeck A....... The methodology provides suggestions on when and how decisions should be made on continuous production methods for Grignard chemistry within pharmaceutical manufacturing. Physicochemical properties, such as solubility, were found to be critical. However, from a business perspective, issues such as the current......The pharmaceutical industry has experienced many changes over the last few decades. Continuous production has been promoted as one of the more promising methods for making the industry more efficient and sustainable. The primary focus of this thesis is on the performance of Grignard chemistry...

  11. Potential and Prospects of Continuous Polyhydroxyalkanoate (PHA Production

    Directory of Open Access Journals (Sweden)

    Martin Koller

    2015-05-01

    Full Text Available Together with other so-called “bio-plastics”, Polyhydroxyalkanoates (PHAs are expected to soon replace established polymers on the plastic market. As a prerequisite, optimized process design is needed to make PHAs attractive in terms of costs and quality. Nowadays, large-scale PHA production relies on discontinuous fed-batch cultivation in huge bioreactors. Such processes presuppose numerous shortcomings such as nonproductive time for reactor revamping, irregular product quality, limited possibility for supply of certain carbon substrates, and, most of all, insufficient productivity. Therefore, single- and multistage continuous PHA biosynthesis is increasingly investigated for production of different types of microbial PHAs; this goes for rather crystalline, thermoplastic PHA homopolyesters as well as for highly flexible PHA copolyesters, and even blocky-structured PHAs consisting of alternating soft and hard segments. Apart from enhanced productivity and constant product quality, chemostat processes can be used to elucidate kinetics of cell growth and PHA formation under constant process conditions. Furthermore, continuous enrichment processes constitute a tool to isolate novel powerful PHA-producing microbial strains adapted to special environmental conditions. The article discusses challenges, potential and case studies for continuous PHA production, and shows up new strategies to further enhance such processes economically by developing unsterile open continuous processes combined with the application of inexpensive carbon feedstocks.

  12. Biohydrogen, bioelectricity and bioalcohols from cellulosic materials

    Energy Technology Data Exchange (ETDEWEB)

    Nissila, M.

    2013-03-01

    The demand for renewable energy is increasing due to increasing energy demand and global warming associated with increasing use of fossil fuels. Renewable energy can be derived from biological production of energy carriers from cellulosic biomass. These biochemical processes include biomass fermentation to hydrogen, methane and alcohols, and bioelectricity production in microbial fuel cells (MFCs). The objective of this study was to investigate the production of different energy carriers (hydrogen, methane, ethanol, butanol, bioelectricity) through biochemical processes. Hydrogen production potential of a hot spring enrichment culture from different sugars was determined, and hydrogen was produced continuously from xylose. Cellulolytic and hydrogenic cultures were enriched on cellulose, cellulosic pulp materials, and on silage at different process conditions. The enrichment cultures were further characterized. The effect of acid pretreatment on hydrogen production from pulp materials was studied and compared to direct pulp fermentation to hydrogen. Electricity and alcohol(s) were simultaneously produced from xylose in MFCs and the exoelectrogenic and alcohologenic enrichment cultures were characterized. In the end, the energy yields obtained from different biochemical processes were determined and compared. In this study, cultures carrying out simultaneous cellulose hydrolysis and hydrogen fermentation were enriched from different sources at different operational conditions. These cultures were successfully utilized for cellulose to hydrogen fermentation in batch systems. Based on these results further research should be conducted on continuous hydrogen production from cellulosic materials.

  13. Open and continuous fermentation: products, conditions and bioprocess economy.

    Science.gov (United States)

    Li, Teng; Chen, Xiang-bin; Chen, Jin-chun; Wu, Qiong; Chen, Guo-Qiang

    2014-12-01

    Microbial fermentation is the key to industrial biotechnology. Most fermentation processes are sensitive to microbial contamination and require an energy intensive sterilization process. The majority of microbial fermentations can only be conducted over a short period of time in a batch or fed-batch culture, further increasing energy consumption and process complexity, and these factors contribute to the high costs of bio-products. In an effort to make bio-products more economically competitive, increased attention has been paid to developing open (unsterile) and continuous processes. If well conducted, continuous fermentation processes will lead to the reduced cost of industrial bio-products. To achieve cost-efficient open and continuous fermentations, the feeding of raw materials and the removal of products must be conducted in a continuous manner without the risk of contamination, even under 'open' conditions. Factors such as the stability of the biological system as a whole during long cultivations, as well as the yield and productivity of the process, are also important. Microorganisms that grow under extreme conditions such as high or low pH, high osmotic pressure, and high or low temperature, as well as under conditions of mixed culturing, cell immobilization, and solid state cultivation, are of interest for developing open and continuous fermentation processes. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Application of polymeric membranes in biohydrogen purification and storage

    Czech Academy of Sciences Publication Activity Database

    Pientka, Zbyněk; Peter, Jakub; Žitka, Jan; Bakonyi, P.

    2014-01-01

    Roč. 1, č. 2 (2014), s. 99-105 ISSN 2212-7119 R&D Projects: GA ČR(CZ) GPP106/12/P643 Institutional support: RVO:61389013 Keywords : biohydrogen * hydrogen * membrane Subject RIV: CD - Macromolecular Chemistry

  15. Continuous hydroponic wheat production using a recirculating system

    Science.gov (United States)

    Mackowiak, C. L.; Owens, L. P.; Hinkle, C. R.; Prince, R. P.

    1989-01-01

    Continuous crop production, where plants of various ages are growing simultaneously in a single recirculating nutrient solution, is a possible alternative to batch production in a Controlled Ecological Life Support System. A study was conducted at John F. Kennedy Space Center where 8 trays (0.24 sq m per tray) of Triticum aestivum L. Yecora Rojo were grown simultaneously in a growth chamber at 23 C, 65 percent relative humidity, 1000 ppm CO2, continuous light, with a continuous flow, thin film nutrient delivery system. The same modified Hoagland nutrient solution was recirculated through the plant trays from an 80 L reservoir throughout the study. It was maintained by periodic addition of water and nutrients based on chemical analyses of the solution. The study was conducted for 216 days, during which 24 trays of wheat were consecutively planted (one every 9 days), 16 of which were grown to maturity and harvested. The remaining 8 trays were harvested on day 216. Grain yields averaged 520 g m(exp -2), and had an average edible biomass of 32 percent. Consecutive yields were unaffected by nutrient solution age. It was concluded that continual wheat production will work in this system over an extended period of time. Certain micronutrient deficiencies and toxicities posed problems and must be addressed in future continuous production systems.

  16. Design of Continuous Crystallizers for Production of Active Pharmaceutical Ingredients

    DEFF Research Database (Denmark)

    Capellades Mendez, Gerard; Christensen, Troels V.

    The production of Active Pharmaceutical Ingredients (APIs) is conducted primarily in batch processes. This manufacturing approach is reinforced by a patent-driven business model and the need to minimize the process development times for newly patented drugs. However, the regulatory and business...... environments are now changing. The increasing costs of drug development, combined with the strict regulations and the competition from generic manufacturers, have pushed pharmaceutical companies to seek cheaper and more sustainable production methods. Transition from batch to Continuous Pharmaceutical...

  17. Continuous Cultivation of Photosynthetic Bacteria for Fatty Acids Production

    DEFF Research Database (Denmark)

    Kim, Dong-Hoon; Lee, Ji-Hye; Hwang, Yuhoon

    2013-01-01

    In the present work, we introduced a novel approach for microbial fatty acids (FA) production. Photosynthetic bacteria, Rhodobacter sphaeroides KD131, were cultivated in a continuous-flow, stirred-tank reactor (CFSTR) at various substrate (lactate) concentrations.At hydraulic retention time (HRT)....... sphaeroides was around 35% of dry cell weight, mainly composed of vaccenic acid (C18:1, omega-7)....

  18. Sustainable production. The ultimate result of a continuous improvement

    NARCIS (Netherlands)

    Ron, de A.J.

    1998-01-01

    To fulfil market requirements, companies have introduced cost awareness, quality programs and techniques to become flexible. These items should be handled as a continuous process of improvement. The cost awareness implies that e.g. material waste is avoided during production, the quality programs

  19. Phase-synchronisation in continuous flow models of production networks

    Science.gov (United States)

    Scholz-Reiter, Bernd; Tervo, Jan Topi; Freitag, Michael

    2006-04-01

    To improve their position at the market, many companies concentrate on their core competences and hence cooperate with suppliers and distributors. Thus, between many independent companies strong linkages develop and production and logistics networks emerge. These networks are characterised by permanently increasing complexity, and are nowadays forced to adapt to dynamically changing markets. This factor complicates an enterprise-spreading production planning and control enormously. Therefore, a continuous flow model for production networks will be derived regarding these special logistic problems. Furthermore, phase-synchronisation effects will be presented and their dependencies to the set of network parameters will be investigated.

  20. A stochastic surplus production model in continuous time

    DEFF Research Database (Denmark)

    Pedersen, Martin Wæver; Berg, Casper Willestofte

    2017-01-01

    surplus production model in continuous time (SPiCT), which in addition to stock dynamics also models the dynamics of the fisheries. This enables error in the catch process to be reflected in the uncertainty of estimated model parameters and management quantities. Benefits of the continuous-time state......Surplus production modelling has a long history as a method for managing data-limited fish stocks. Recent advancements have cast surplus production models as state-space models that separate random variability of stock dynamics from error in observed indices of biomass. We present a stochastic......-space model formulation include the ability to provide estimates of exploitable biomass and fishing mortality at any point in time from data sampled at arbitrary and possibly irregular intervals. We show in a simulation that the ability to analyse subannual data can increase the effective sample size...

  1. Production of continuous mullite fiber via sol-gel processing

    Science.gov (United States)

    Tucker, Dennis S.; Sparks, J. Scott; Esker, David C.

    1990-01-01

    The development of a continuous ceramic fiber which could be used in rocket engine and rocket boosters applications was investigated at the Marshall Space Flight Center. Methods of ceramic fiber production such as melt spinning, chemical vapor deposition, and precursor polymeric fiber decomposition are discussed and compared with sol-gel processing. The production of ceramics via the sol-gel method consists of two steps, hydrolysis and polycondensation, to form the preceramic, followed by consolidation into the glass or ceramic structure. The advantages of the sol-gel method include better homogeneity and purity, lower preparation temperature, and the ability to form unique compositions. The disadvantages are the high cost of raw materials, large shrinkage during drying and firing which can lead to cracks, and long processing times. Preparation procedures for aluminosilicate sol-gel and for continuous mullite fibers are described.

  2. Hydrogen production from algal biomass - Advances, challenges and prospects.

    Science.gov (United States)

    Show, Kuan-Yeow; Yan, Yuegen; Ling, Ming; Ye, Guoxiang; Li, Ting; Lee, Duu-Jong

    2018-06-01

    Extensive effort is being made to explore renewable energy in replacing fossil fuels. Biohydrogen is a promising future fuel because of its clean and high energy content. A challenging issue in establishing hydrogen economy is sustainability. Biohydrogen has the potential for renewable biofuel, and could replace current hydrogen production through fossil fuel thermo-chemical processes. A promising source of biohydrogen is conversion from algal biomass, which is abundant, clean and renewable. Unlike other well-developed biofuels such as bioethanol and biodiesel, production of hydrogen from algal biomass is still in the early stage of development. There are a variety of technologies for algal hydrogen production, and some laboratory- and pilot-scale systems have demonstrated a good potential for full-scale implementation. This work presents an elucidation on development in biohydrogen encompassing biological pathways, bioreactor designs and operation and techno-economic evaluation. Challenges and prospects of biohydrogen production are also outlined. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Biohydrogen recovery and purification by gas separation method

    Czech Academy of Sciences Publication Activity Database

    Búcsú, D.; Pientka, Zbyněk; Kovács, S.; Bélafi-Bakó, K.

    2006-01-01

    Roč. 200, 1-3 (2006), s. 227-229 ISSN 0011-9164. [Conference Euromembrane. Giardini Naxos - Taormina, 24.09.2006-28.09.2006] R&D Projects: GA ČR GA203/06/1207 Grant - others:Czech-Hungarian Bilateral Research Programme(HU) CZN-16/2005 Institutional research plan: CEZ:AV0Z40500505 Keywords : biohydrogen * gas separation membranes * polymer membranes Subject RIV: CD - Macromolecular Chemistry Impact factor: 0.917, year: 2006

  4. Optimization of asparaginase production from Zymomonas mobilis by continuous fermentation

    Directory of Open Access Journals (Sweden)

    Francieli Bortoluzzi Menegat

    2016-10-01

    Full Text Available Asparaginase is an enzyme used in clinical treatments as a chemotherapeutic agent and in food technology to prevent acrylamide formation in fried and baked foods. Asparaginase is industrially produced by microorganisms, mainly gram-negative bacteria. Zymomonas mobilis is a Gram-negative bacterium that utilizes glucose, fructose and sucrose as carbon source and has been known for its efficiency in producing ethanol, sorbitol, levan, gluconic acid and has recently aroused interest for asparaginase production. Current assay optimizes the production of Z. mobilis asparaginase by continuous fermentation using response surface experimental design and methodology. The studied variables comprised sucrose, yeast extract and asparagine. Optimized condition obtained 117.45 IU L-1 with dilution rate 0.20 h-1, yeast extract 0.5 g L-1, sucrose 20 g L-1 and asparagine 1.3 g L-1. Moreover, carbon:nitrogen ratio (1:0.025 strongly affected the response of asparaginase activity. The use of Z. mobilis by continuous fermentation has proved to be a promising alternative for the biotechnological production of asparaginase.

  5. Product differentiation during continuous-flow thermal gradient PCR.

    Science.gov (United States)

    Crews, Niel; Wittwer, Carl; Palais, Robert; Gale, Bruce

    2008-06-01

    A continuous-flow PCR microfluidic device was developed in which the target DNA product can be detected and identified during its amplification. This in situ characterization potentially eliminates the requirement for further post-PCR analysis. Multiple small targets have been amplified from human genomic DNA, having sizes of 108, 122, and 134 bp. With a DNA dye in the PCR mixture, the amplification and unique melting behavior of each sample is observed from a single fluorescent image. The melting behavior of the amplifying DNA, which depends on its molecular composition, occurs spatially in the thermal gradient PCR device, and can be observed with an optical resolution of 0.1 degrees C pixel(-1). Since many PCR cycles are within the field of view of the CCD camera, melting analysis can be performed at any cycle that contains a significant quantity of amplicon, thereby eliminating the cycle-selection challenges typically associated with continuous-flow PCR microfluidics.

  6. Continuous dry fermentation of swine manure for biogas production

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chuang; Zheng, Dan [Biogas Institute of Ministry of Agriculture, Chengdu 610041 (China); Liu, Gang–Jin [Biogas Institute of Ministry of Agriculture, Chengdu 610041 (China); Bioprocess Control AB, Scheelevägen 22, 223 63 Lund (Sweden); Deng, Liang–Wei, E-mail: dengliangwei@caas.cn [Biogas Institute of Ministry of Agriculture, Chengdu 610041 (China); Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture, Chengdu 610041 (China); Southwest Collaborative Innovation Center of Swine for Quality & Safety, Chengdu 611130 (China); Long, Yan; Fan, Zhan–Hui [Biogas Institute of Ministry of Agriculture, Chengdu 610041 (China)

    2015-04-15

    Highlights: • Continuous dry fermentation of swine manure for biogas production is feasible. • The feedstock TS concentration exerted a significant impact on biogas production. • Influences of ammonia and digestate liquidity were investigated in this study. • The results showed that the feedstock TS of swine manure should not exceed 30%. - Abstract: A down plug-flow anaerobic reactor (DPAR) was designed for the feasibility study on continuous dry fermentation of swine manure without any additional stirring. Using fresh swine manure as the feedstock with TS concentration (w/w) of 20%, 25%, 30%, and 35%, stable volumetric biogas production rates of 2.40, 1.92, 0.911, and 0.644 L·(L d){sup −1} and biogas yields of 0.665, 0.532, 0.252, and 0.178 L g{sup −1}VS were obtained respectively, and the TS degradation rates were 46.5%, 45.4%, 53.2%, and 55.6%, respectively. With the increase of feedstock TS concentration, the concentration of ammonia nitrogen grew up to the maximum value of 3500 mg L{sup −1}. Biogas production was obviously inhibited when the concentration of ammonia nitrogen was above 3000 mg L{sup −1}. The maximal volumetric biogas production rate of 2.34 L·(L d){sup −1} and biogas yield of 0.649 L g{sup −1}VS were obtained with TS concentration of 25% at 25 °C without inhibition. Liquidity experiments showed that TS concentration of digestate could be less than 15.8%, and the flow rate of digestate more than 0.98 m s{sup −1} when the feedstock TS concentration was less than 35%, which indicated the digestate could be easily discharged from a DPAR. Therefore, it is feasible to conduct a continuous dry fermentation in a DPAR using fresh swine manure as the feedstock with TS concentration less than 35%, whereas the feedstock TS concentration should not exceed 30% to achieve the maximal biogas production rate and biogas yield.

  7. Continuous dry fermentation of swine manure for biogas production

    International Nuclear Information System (INIS)

    Chen, Chuang; Zheng, Dan; Liu, Gang–Jin; Deng, Liang–Wei; Long, Yan; Fan, Zhan–Hui

    2015-01-01

    Highlights: • Continuous dry fermentation of swine manure for biogas production is feasible. • The feedstock TS concentration exerted a significant impact on biogas production. • Influences of ammonia and digestate liquidity were investigated in this study. • The results showed that the feedstock TS of swine manure should not exceed 30%. - Abstract: A down plug-flow anaerobic reactor (DPAR) was designed for the feasibility study on continuous dry fermentation of swine manure without any additional stirring. Using fresh swine manure as the feedstock with TS concentration (w/w) of 20%, 25%, 30%, and 35%, stable volumetric biogas production rates of 2.40, 1.92, 0.911, and 0.644 L·(L d) −1 and biogas yields of 0.665, 0.532, 0.252, and 0.178 L g −1 VS were obtained respectively, and the TS degradation rates were 46.5%, 45.4%, 53.2%, and 55.6%, respectively. With the increase of feedstock TS concentration, the concentration of ammonia nitrogen grew up to the maximum value of 3500 mg L −1 . Biogas production was obviously inhibited when the concentration of ammonia nitrogen was above 3000 mg L −1 . The maximal volumetric biogas production rate of 2.34 L·(L d) −1 and biogas yield of 0.649 L g −1 VS were obtained with TS concentration of 25% at 25 °C without inhibition. Liquidity experiments showed that TS concentration of digestate could be less than 15.8%, and the flow rate of digestate more than 0.98 m s −1 when the feedstock TS concentration was less than 35%, which indicated the digestate could be easily discharged from a DPAR. Therefore, it is feasible to conduct a continuous dry fermentation in a DPAR using fresh swine manure as the feedstock with TS concentration less than 35%, whereas the feedstock TS concentration should not exceed 30% to achieve the maximal biogas production rate and biogas yield

  8. Increased performance of continuous stirred tank reactor with calcium supplementation

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Zhuliang; Yang, Haijun; Zhi, Xiaohua; Shen, Jianquan [Beijing National Laboratory for Molecular Sciences (BNLMS), New Materials Laboratory, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

    2010-04-15

    Continuous biohydrogen production with calcium supplementation at low hydraulic retention time (HRT) in a continuous stirred tank reactor (CSTR) was studied to maximize the hydrogen productivity of anaerobic mixed cultures. After stable operations at HRT of 8-4 h, the bioreactor became unstable when the HRT was lowered to 2 h. Supplementation of 100 mg/L calcium at HRT 2 h improved the operation stability through enhancement of cell retention with almost two-fold increase in cell density than that without calcium addition. Hydrogen production rate and hydrogen yield reached 24.5 L/d/L and 3.74 mol H{sub 2}/mol sucrose, respectively, both of which were the highest values our group have ever achieved. The results showed that calcium supplementation can be an effective way to improve the performance of CSTR at low HRT. (author)

  9. Nonlinear adaptive optimization of biomass productivity in continuous bioreactors

    Energy Technology Data Exchange (ETDEWEB)

    Sauvaire, P; Mellichamp, D A; Agrawal, P [California Univ., Santa Barbara, CA (United States). Dept. of Chemical and Nuclear Engineering

    1991-11-01

    A novel on-line adaptive optimization algorithm is developed and applied to continuous biological reactors. The algorithm makes use of a simple nonlinear estimation model that relates either the cell-mass productivity or the cell-mass concentration to the dilution rate. On-line estimation is used to recursively identify the parameters in the nonlinear process model and to periodically calculate and steer the bioreactor to the dilution rate that yields optimum cell-mass productivity. Thus, the algorithm does not require an accurate process model, locates the optimum dilution rate online, and maintains the bioreactors at this optimum condition at all times. The features of the proposed new algorithm are compared with those of other adaptive optimization techniques presented in the literature. A detailed simulation study using three different microbial system models was conducted to illustrate the performance of the optimization algorithms. (orig.).

  10. Use of tower reactors for continuous ethanol production

    Directory of Open Access Journals (Sweden)

    M.C. Viegas

    2002-04-01

    Full Text Available The purpose of this work was to develop a continuous fermentation system operating with a tower reactor using some flocculent yeast strains isolated from an industrial process. The strain was an used in the trial of the proposed system, composed of two serial glass tower reactor. The effects of the following variables were studied on the yield and productivity of the system: total reducing sugar (TRS, concentration in feeding, recycle flow in the second reactor, residence time and diameter/height ratio of the reactors. It was observed that the TRS concentration in feeding and residence time is the variables that interfere most with the productivity of the system. Yield was not affected by any of the variables within the range of values studied. All trials were performed according to a factorial experimental design (making up a total of 19 trials and the results were evaluated by response surface.

  11. Landsat Data Continuity Mission (LDCM) Standard Product Generation and Characteristics

    Science.gov (United States)

    Micijevic, E.; Hayes, R.

    2012-12-01

    prefer uncorrected data a Level 0 Reformatted Product (L0Rp) product will be available. The standard L1T product for L8 will be a 16-bit, north up Universal Transverse Mercator (UTM) projection, Cubic Convolution (CC) resampled, GeoTIFF file. The delivered tar file contains eight 30-meter OlI multispectral bands, one 15-meter OLI Panchromatic band, two TIRS thermal bands, a Quality Band (QB), a metadata file, and an Angle Band. The QB is a file that contains quality statistics from the image data and cloud mask for the scene. The metadata file contains information about the product ordered and is essential for the end user to know how that product was processed. The Angle Band is a binary image file that contains the solar angle information for the scene data collected. The L1T reflectance product bands will be generated with no sun angle correction applied. The angle band will enable an optional TOA reflectance calculation using the sun angles specific to each image pixel. This method was chosen to maintain continuity with Landsat products while allowing the users that require a per pixel sun angle correction to have that capability. An example of a L8 product can be downloaded from the Landsat website located at: http://landsat.usgs.gov/LDCM_DataProduct.php. The sample L8 product was created using Landsat 7 data projected onto a L8 grid and processed to LDCM data product specifications.

  12. An integrated system for hydrogen and methane production during landfill leachate treatment

    Energy Technology Data Exchange (ETDEWEB)

    Hafez, H.M.; Nakhla, G.; El Naggar, H. [Western Ontario Univ., London, ON (Canada). Dept. of Civil and Environmental Engineering

    2009-07-01

    This paper described a patent-pending integrated waste-to-energy system that includes a novel biohydrogen reactor with a gravity settler and a second stage conventional anaerobic digester for the production of methane gas. This chemical-free process was tested using a synthetic wastewater/leachate solution at 37 degrees C for 45 days. During the experimental period, the biohydrogenator steadily produced hydrogen (H{sub 2}) with no methane. The maximum hydrogen yield was 400 ml H{sub 2}/g glucose with an average of 345 ml H{sub 2}/g glucose, as compared to 141 and 118 ml H{sub 2}/g glucose for two consecutive runs done in parallel using a conventional continuously stirrer tank reactor. The maximum and average hydrogen production rates in the biohydrogen reactor with gravity settler were 22 and 19 L H{sub 2}/day, the maximum yield was 2.8 mol H{sub 2} /mol glucose higher than 1.6-2.3 mol H{sub 2}/mol glucose reported for continuous-flow reactors. The methane yield for the second stage approached a maximum value of 426 ml methane/g chemical oxygen demand (COD) removed.

  13. Continuous dry fermentation of swine manure for biogas production.

    Science.gov (United States)

    Chen, Chuang; Zheng, Dan; Liu, Gang-Jin; Deng, Liang-Wei; Long, Yan; Fan, Zhan-Hui

    2015-04-01

    A down plug-flow anaerobic reactor (DPAR) was designed for the feasibility study on continuous dry fermentation of swine manure without any additional stirring. Using fresh swine manure as the feedstock with TS concentration (w/w) of 20%, 25%, 30%, and 35%, stable volumetric biogas production rates of 2.40, 1.92, 0.911, and 0.644L · (Ld)(-1) and biogas yields of 0.665, 0.532, 0.252, and 0.178 L g(-)(1)VS were obtained respectively, and the TS degradation rates were 46.5%, 45.4%, 53.2%, and 55.6%, respectively. With the increase of feedstock TS concentration, the concentration of ammonia nitrogen grew up to the maximum value of 3500 mg L(-1). Biogas production was obviously inhibited when the concentration of ammonia nitrogen was above 3000 mg L(-1). The maximal volumetric biogas production rate of 2.34 L ·(Ld)(-1) and biogas yield of 0.649 L g(-1)VS were obtained with TS concentration of 25% at 25°C without inhibition. Liquidity experiments showed that TS concentration of digestate could be less than 15.8%, and the flow rate of digestate more than 0.98 m s(-1) when the feedstock TS concentration was less than 35%, which indicated the digestate could be easily discharged from a DPAR. Therefore, it is feasible to conduct a continuous dry fermentation in a DPAR using fresh swine manure as the feedstock with TS concentration less than 35%, whereas the feedstock TS concentration should not exceed 30% to achieve the maximal biogas production rate and biogas yield. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Attainable region analysis for continuous production of second generation bioethanol.

    Science.gov (United States)

    Scott, Felipe; Conejeros, Raúl; Aroca, Germán

    2013-11-29

    Despite its semi-commercial status, ethanol production from lignocellulosics presents many complexities not yet fully solved. Since the pretreatment stage has been recognized as a complex and yield-determining step, it has been extensively studied. However, economic success of the production process also requires optimization of the biochemical conversion stage. This work addresses the search of bioreactor configurations with improved residence times for continuous enzymatic saccharification and fermentation operations. Instead of analyzing each possible configuration through simulation, we apply graphical methods to optimize the residence time of reactor networks composed of steady-state reactors. Although this can be easily made for processes described by a single kinetic expression, reactions under analysis do not exhibit this feature. Hence, the attainable region method, able to handle multiple species and its reactions, was applied for continuous reactors. Additionally, the effects of the sugars contained in the pretreatment liquor over the enzymatic hydrolysis and simultaneous saccharification and fermentation (SSF) were assessed. We obtained candidate attainable regions for separate enzymatic hydrolysis and fermentation (SHF) and SSF operations, both fed with pretreated corn stover. Results show that, despite the complexity of the reaction networks and underlying kinetics, the reactor networks that minimize the residence time can be constructed by using plug flow reactors and continuous stirred tank reactors. Regarding the effect of soluble solids in the feed stream to the reactor network, for SHF higher glucose concentration and yield are achieved for enzymatic hydrolysis with washed solids. Similarly, for SSF, higher yields and bioethanol titers are obtained using this substrate. In this work, we demonstrated the capabilities of the attainable region analysis as a tool to assess the optimal reactor network with minimum residence time applied to the SHF and

  15. An integrated system for hydrogen and methane production during landfill leachate treatment

    Energy Technology Data Exchange (ETDEWEB)

    Hafez, Hisham; Nakhla, George; El Naggar, Hesham [Civil and Environmental Engineering Department, University of Western Ontario, London, Ontario (Canada)

    2010-05-15

    The patent-pending integrated waste-to-energy system comprises both a novel biohydrogen reactor with a gravity settler (Biohydrogenator), followed by a second stage conventional anaerobic digester for the production of methane gas. This chemical-free process has been tested with a synthetic wastewater/leachate solution, and was operated at 37 C for 45 d. The biohydrogenator (system (A), stage 1) steadily produced hydrogen with no methane during the experimental period. The maximum hydrogen yield was 400 mL H{sub 2}/g glucose with an average of 345 mL H{sub 2}/g glucose, as compared to 141 and 118 mL H{sub 2}/g glucose for two consecutive runs done in parallel using a conventional continuously stirred tank reactor (CSTR, System (B)). Decoupling of the solids retention time (SRT) from the hydraulic retention time (HRT) using the gravity settler showed a marked improvement in performance, with the maximum and average hydrogen production rates in system (A) of 22 and 19 L H{sub 2}/d, as compared with 2-7 L H{sub 2}/d in the CSTR resulting in a maximum yield of 2.8 mol H{sub 2}/mol glucose much higher than the 1.1-1.3 mol H{sub 2}/mol glucose observed in the CSTR. Furthermore, while the CSTR collapsed in 10-15 d due to biomass washout, the biohydrogenator continued stable operation for the 45 d reported here and beyond. The methane yield for the second stage in system (A) approached a maximum value of 426 mL CH{sub 4}/gCOD removed, while an overall chemical oxygen demand (COD) removal efficiency of 94% was achieved in system (A). (author)

  16. Continued SOFC cell and stack technology and improved production methods

    Energy Technology Data Exchange (ETDEWEB)

    Wandel, M.; Brodersen, K.; Phair, J. (and others)

    2009-05-15

    Within this project significant results are obtained on a number of very diverse areas ranging from development of cell production, metallic creep in interconnect to assembling and test of stacks with foot print larger than 500 cm2. Out of 38 milestones 28 have been fulfilled and 10 have been partly fulfilled. This project has focused on three main areas: 1) The continued cell development and optimization of manufacturing processes aiming at production of large foot-print cells, improving cell performance and development environmentally more benign production methods. 2) Stack technology - especially stacks with large foot print and improving the stack design with respect to flow geometry and gas leakages. 3) Development of stack components with emphasis on sealing (for 2G as well as 3G), interconnect (coat, architecture and creep) and test development. Production of cells with a foot print larger than 500 cm2 is very difficult due to the brittleness of the cells and great effort has been put into this topic. Eight cells were successfully produced making it possible to assemble and test a real stack thereby giving valuable results on the prospects of stacks with large foot print. However, the yield rate is very low and a significant development to increase this yield lies ahead. Several lessons were learned on the stack level regarding 'large foot print' stacks. Modelling studies showed that the width of the cell primarily is limited by production and handling of the cell whereas the length (in the flow direction) is limited by e.g. pressure drop and necessary manifolding. The optimal cell size in the flow direction was calculated to be between approx20 cm and < 30 cm. From an economical point of view the production yield is crucial and stacks with large foot print cell area are only feasible if the cell production yield is significantly enhanced. Co-casting has been pursued as a production technique due to the possibilities in large scale production

  17. Continuous fermentative hydrogen production in different process conditions

    Energy Technology Data Exchange (ETDEWEB)

    Nasirian, N. [Islamic Azad Univ., Shoushtar (Iran, Islamic Republic of). Dept. of Agricultural Mechanization; Almassi, M.; Minaee, S. [Islamic Azad Univ., Tehran (Iran, Islamic Republic of). Dept. of Agricultural Mechanization; Widmann, R. [Duisburg-Essen Univ., Essen (Germany). Dept. of Environmental Engineering, Waste and Water

    2010-07-01

    This paper reported on a study in which hydrogen was produced by fermentation of biomass. A continuous process using a non-sterile substrate with a readily available mixed microflora was used on heat treated digested sewage sludge from a wastewater treatment plant. Hydrogen was produced from waste sugar at a pH of 5.2 and a temperature of 37 degrees C. An experimental setup of three 5.5 L working volume continuously stirred tank reactors (CSTR) in different stirring speeds were constructed and operated at 7 different hydraulic retention times (HRTs) and different organic loading rates (OLR). Dissolved organic carbon was examined. The results showed that the stirring speed of 135 rpm had a beneficial effect on hydrogen fermentation. The best performance was obtained in 135 rpm and 8 h of HRT. The amount of gas varied with different OLRs, but could be stabilized on a high level. Methane was not detected when the HRT was less than 16 h. The study identified the reactor in which the highest specific rate of hydrogen production occurred.

  18. Continuous production of nanostructured particles using spatial atomic layer deposition

    International Nuclear Information System (INIS)

    Ommen, J. Ruud van; Kooijman, Dirkjan; Niet, Mark de; Talebi, Mojgan; Goulas, Aristeidis

    2015-01-01

    In this paper, the authors demonstrate a novel spatial atomic layer deposition (ALD) process based on pneumatic transport of nanoparticle agglomerates. Nanoclusters of platinum (Pt) of ∼1 nm diameter are deposited onto titania (TiO 2 ) P25 nanoparticles resulting to a continuous production of an active photocatalyst (0.12–0.31 wt. % of Pt) at a rate of about 1 g min −1 . Tuning the precursor injection velocity (10–40 m s −1 ) enhances the contact between the precursor and the pneumatically transported support flows. Decreasing the chemisorption temperature (from 250 to 100 °C) results in more uniform distribution of the Pt nanoclusters as it decreases the reaction rate as compared to the rate of diffusion into the nanoparticle agglomerates. Utilizing this photocatalyst in the oxidation reaction of Acid Blue 9 showed a factor of five increase of the photocatalytic activity compared to the native P25 nanoparticles. The use of spatial particle ALD can be further expanded to deposition of nanoclusters on porous, micron-sized particles and to the production of core–shell nanoparticles enabling the robust and scalable manufacturing of nanostructured powders for catalysis and other applications

  19. A continuous spectrophotometric assay for monitoring adenosine 5'-monophosphate production.

    Science.gov (United States)

    First, Eric A

    2015-08-15

    A number of biologically important enzymes release adenosine 5'-monophosphate (AMP) as a product, including aminoacyl-tRNA synthetases, cyclic AMP (cAMP) phosphodiesterases, ubiquitin and ubiquitin-like ligases, DNA ligases, coenzyme A (CoA) ligases, polyA deadenylases, and ribonucleases. In contrast to the abundance of assays available for monitoring the conversion of adenosine 5'-triphosphate (ATP) to ADP, there are relatively few assays for monitoring the conversion of ATP (or cAMP) to AMP. In this article, we describe a homogeneous assay that continuously monitors the production of AMP. Specifically, we have coupled the conversion of AMP to inosine 5'-monophosphate (IMP) (by AMP deaminase) to the oxidation of IMP (by IMP dehydrogenase). This results in the reduction of oxidized nicotine adenine dinucleotide (NAD(+)) to reduced nicotine adenine dinucleotide (NADH), allowing AMP formation to be monitored by the change in the absorbance at 340 nm. Changes in AMP concentrations of 5 μM or more can be reliably detected. The ease of use and relatively low expense make the AMP assay suitable for both high-throughput screening and kinetic analyses. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. High-rate continuous hydrogen production by Thermoanaerobacterium thermosaccharolyticum PSU-2 immobilized on heat-pretreated methanogenic granules

    Energy Technology Data Exchange (ETDEWEB)

    O-Thong, Sompong [Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet 115, DK-2800, Kgs Lyngby (Denmark); Department of Biology, Faculty of Science, Thaksin University, Patthalung 93110 (Thailand); Prasertsan, Poonsuk [Department of Industrial Biotechnology, Faculty of Agro-Industry, Prince of Songkla University, Hat-Yai, Songkhla 90120 (Thailand); Karakashev, Dimitar; Angelidaki, Irini [Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet 115, DK-2800, Kgs Lyngby (Denmark)

    2008-11-15

    Biohydrogen production from Thermoanaerobacterium thermosaccharolyticum strain PSU-2 was examined in upflow anaerobic sludge blanket (UASB) reactor and carrier-free upflow anaerobic reactor (UA), both fed with sucrose and operating at 60 C. Heat-pretreated methanogenic granules were used as carrier to immobilize T. thermosaccharolyticum strain PSU-2 in UASB reactor operated at a hydraulic retention time (HRT) ranging from 0.75 to 24 h and corresponding sucrose loading rate from 58.5 to 2.4 mmol sucrose l{sup -1} h{sup -1}. In comparison with hydrogen production rate of 12.1 mmol H{sub 2} l{sup -1} h{sup -1} obtained by carrier-free reactor upflow anaerobic (UA) system, a greatly improved hydrogen production rate up to 152 mmol H{sub 2} l{sup -1} h{sup -1} was demonstrated by the granular cells in UASB system. The biofilm of T. thermosaccharolyticum strain PSU-2 developed on treated methanogenic granules in UASB reactor substantially enhanced biomass retention (3 times), and production of hydrogen (12 times) compared to carrier-free reactor. It appears to be the most preferred process for highly efficient dark fermentative hydrogen production from sugar containing wastewater under thermophilic conditions. (author)

  1. Rings of continuous functions, symmetric products, and Frobenius algebras

    International Nuclear Information System (INIS)

    Buchstaber, Viktor M; Rees, E G

    2004-01-01

    A constructive proof is given for the classical theorem of Gel'fand and Kolmogorov (1939) characterising the image of the evaluation map from a compact Hausdorff space X into the linear space C(X)* dual to the ring C(X) of continuous functions on X. Our approach to the proof enabled us to obtain a more general result characterising the image of the evaluation map from the symmetric products Sym n (X) into C(X)*. A similar result holds if X=C m and leads to explicit equations for symmetric products of affine algebraic varieties as algebraic subvarieties in the linear space dual to the polynomial ring. This leads to a better understanding of the algebra of multisymmetric polynomials. The proof of all these results is based on a formula used by Frobenius in 1896 in defining higher characters of finite groups. This formula had no further applications for a long time; however, it has appeared in several independent contexts during the last fifteen years. It was used by A. Wiles and R.L. Taylor in studying representations and by H.-J. Hoehnke and K.W. Johnson and later by J. McKay in studying finite groups. It plays an important role in our work concerning multivalued groups. Several properties of this remarkable formula are described. It is also used to prove a theorem on the structure constants of Frobenius algebras, which have recently attracted attention due to constructions taken from topological field theory and singularity theory. This theorem develops a result of Hoehnke published in 1958. As a corollary, a direct self-contained proof is obtained for the fact that the 1-, 2-, and 3-characters of the regular representation determine a finite group up to isomorphism. This result was first published by Hoehnke and Johnson in 1992

  2. Process performance and product quality in an integrated continuous antibody production process.

    Science.gov (United States)

    Karst, Daniel J; Steinebach, Fabian; Soos, Miroslav; Morbidelli, Massimo

    2017-02-01

    Continuous manufacturing is currently being seriously considered in the biopharmaceutical industry as the possible new paradigm for producing therapeutic proteins, due to production cost and product quality related benefits. In this study, a monoclonal antibody producing CHO cell line was cultured in perfusion mode and connected to a continuous affinity capture step. The reliable and stable integration of the two systems was enabled by suitable control loops, regulating the continuous volumetric flow and adapting the operating conditions of the capture process. For the latter, an at-line HPLC measurement of the harvest concentration subsequent to the bioreactor was combined with a mechanistic model of the capture chromatographic unit. Thereby, optimal buffer consumption and productivity throughout the process was realized while always maintaining a yield above the target value of 99%. Stable operation was achieved at three consecutive viable cell density set points (20, 60, and 40 × 10 6 cells/mL), together with consistent product quality in terms of aggregates, fragments, charge isoforms, and N-linked glycosylation. In addition, different values for these product quality attributes such as N-linked glycosylation, charge variants, and aggregate content were measured at the different steady states. As expected, the amount of released DNA and HCP was significantly reduced by the capture step for all considered upstream operating conditions. This study is exemplary for the potential of enhancing product quality control and modulation by integrated continuous manufacturing. Biotechnol. Bioeng. 2017;114: 298-307. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. The Current of Continuing Professional Development for Product Designers

    OpenAIRE

    山内, 勉; Yamauchi, Tsutomu

    2010-01-01

    Product Designers are required some skills and knowledge in the product development. Based on my professional career, I presumed three skills, they are, Technical skills, Conceptual skills and Human skills. In this study, I interviewed some Product Designers to make sure what skills are needed in the product development process. It emerged that Product Designers are expected to improve their Conceptual and Human skills besides Technical skills for playing a part at the upper and lower stage o...

  4. Modulation of in vitro rumen biohydrogenation by Cistus ladanifer tannins compared with other tannin sources.

    Science.gov (United States)

    Costa, Mónica; Alves, Susana P; Cabo, Ângelo; Guerreiro, Olinda; Stilwell, George; Dentinho, Maria T; Bessa, Rui Jb

    2017-01-01

    Tannins are polyphenolic compounds able to modify the ruminal biohydrogenation (BH) of unsaturated fatty acids, but their activity may vary among different tannin sources. The effect of rockrose (Cistus ladanifer) on BH has never been compared with other more common tannin sources. Tannin extracts (100 g kg -1 substrate dry matter) from chestnut (CH), quebracho (QB), grape seed (GS) and rockrose (CL) were incubated in vitro for 6 h with ruminal fluid using as substrate a feed containing 60 g kg -1 of sunflower oil. A control treatment with no added tannins was also included. Compared with the control, GS and CL, but not CH and QB, increased (P 0.05) were observed for the disappearance of c9-18:1 and c9,c12,c15-18:3. The production of 18:0 was not different (P > 0.05) among treatments, although its proportion in the total BH products was lower (P < 0.05) for GS than for the other treatments. Condensed tannins from GS and, to a lesser extent, from CL stimulate the first steps of BH, without a clear inhibition of 18:0 production. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  5. 9 CFR 590.24 - Egg products plants requiring continuous inspection.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Egg products plants requiring..., DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION OF EGGS AND EGG PRODUCTS (EGG PRODUCTS INSPECTION ACT) Scope of Inspection § 590.24 Egg products plants requiring continuous inspection. No plant in...

  6. Productivity Continued to Increase in Many Industries during 1984.

    Science.gov (United States)

    Herman, Arthur S.

    1986-01-01

    Productivity, as measured by output per employee hour, grew in 1984 in about three quarters of the industries for which the Bureau of Labor Statistics regularly publishes data. (A table shows productivity trends in industries measured by the Bureau, including mining, transportation and utilities, and trade and services.) (CT)

  7. Productivity of grasslands under continuous and rotational grazing

    NARCIS (Netherlands)

    Lantinga, E.A.

    1985-01-01

    In the Netherlands, rotational grazing, with grazing periods of 2 to 5 days, is the most common grazing system at present. In contrast with other countries of North-western Europe, the continuous grazing system is used here only to a limited extent. However, the results of numerous

  8. The uses of continuous thermodynamics in the perfluoropolieter production

    International Nuclear Information System (INIS)

    Silva, Eduardo Ramos Ferreira da; Terron, Luiz Roberto

    1995-01-01

    The use of continuous thermodynamics technic is crescent in the resolution of problems found in the chemical engineering process, involving complex mixtures. This new technic substitute, with advantages (larger precision and less CPU time) the traditional method (pseudo components method) and can can also be used in nuclear technology, when problems involving complexes mixtures are presented. (author). 37 refs

  9. Continued slide seen for C.I.S. oil production

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This paper reports that oil production in the Commonwealth of Independent States may dip to 7.7 million b/d next year. Robert Ebel of the Center for strategic and International Studies, Washington, D.C., made that prediction before a meeting of the National Association of Petroleum Investment Analysts. Oil and Gas Journal's latest worldwide oil production figures peg the C.I.S. volume at 8.689 million b/d last August. Ebel said a September decree will allow oil prices to move in line with the market and with costs of production. That in turn will lead to development of a deregulated domestic oil market

  10. Microbial production of a biofuel (acetone-butanol-ethanol) in a continuous bioreactor: impact of bleed and simultaneous product removal

    Science.gov (United States)

    Acetone butanol ethanol (ABE) was produced in an integrated continuous fermentation and product recovery system using a microbial strain Clostridium beijerinckii BA101 for ABE production and fermentation gases (CO2 and H2) for product removal by gas stripping. This represents a continuation of our ...

  11. Modelling of biohydrogen production and recovery by membrane gas separation

    Czech Academy of Sciences Publication Activity Database

    Búcsú, D.; Nemestóthy, N.; Pientka, Zbyněk; Gubicza, L.; Bélafi-Bakó, K.

    2009-01-01

    Roč. 240, 1-3 (2009), s. 306-310 ISSN 0011-9164 R&D Projects: GA ČR GA203/06/1207 Institutional research plan: CEZ:AV0Z40500505 Keywords : integrated system * Escherichia coli * PES-PI membrane Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.034, year: 2009

  12. Apparatus and method for continuous production of materials

    Science.gov (United States)

    Chang, Chih-hung; Jin, Hyungdae

    2014-08-12

    Embodiments of a continuous-flow injection reactor and a method for continuous material synthesis are disclosed. The reactor includes a mixing zone unit and a residence time unit removably coupled to the mixing zone unit. The mixing zone unit includes at least one top inlet, a side inlet, and a bottom outlet. An injection tube, or plurality of injection tubes, is inserted through the top inlet and extends past the side inlet while terminating above the bottom outlet. A first reactant solution flows in through the side inlet, and a second reactant solution flows in through the injection tube(s). With reference to nanoparticle synthesis, the reactant solutions combine in a mixing zone and form nucleated nanoparticles. The nucleated nanoparticles flow through the residence time unit. The residence time unit may be a single conduit, or it may include an outer housing and a plurality of inner tubes within the outer housing.

  13. Continuous photocatalytic fuel production over wide-bandgap metal oxides

    OpenAIRE

    Bazzo, Antonio

    2014-01-01

    Artificial photosynthesis has been proposed as one of the possible solutions to the energetic and chemical-feedstock problems to cope with the anticipated near future depletion of fossil fuel resources. This doctoral thesis deals with the study of promising catalysts and reactor designs to enhance the reaction efficiency and understand the origin of photocatalytic activity. A continuous flow reaction system was designed and constructed to study CO2 photoreduction with H2O and photocatalytic w...

  14. Study of advanced control of ethanol production through continuous fermentation

    Directory of Open Access Journals (Sweden)

    AbdelHamid Ajbar

    2017-01-01

    Full Text Available This paper investigates the control of an experimentally validated model of production of bioethanol. The analysis of the open loop system revealed that the maximum productivity occurred at a periodic point. A robust control was needed to avoid instabilities that may occur when disturbances are injected into the process that may drive it toward or through the unstable points. A nonlinear model predictive controller (NLMPC was used to control the process. Simulation tests were carried out using three controlled variables: the ethanol concentration, the productivity and the inverse of the productivity. In the third configuration, the controller was required to seek the maximum operating point through the optimization capability built in the NLMPC algorithm. Simulation tests presented overall satisfactory closed-loop performance for both nominal servo and regulatory control problems as well as in the presence of modeling errors. The third control configuration managed to steer the process toward the existing maximum productivity even when the process operation or its parameters changed. For comparison purposes, a standard PI controller was also designed for the same control objectives. The PI controller yielded satisfactory performance when the ethanol concentration was chosen as the controlled variable. When, on the other hand, the productivity was chosen as the controlled output, the PI controller did not work properly and needed to be adjusted using gain scheduling. In all cases, it was observed that the closed-loop response suffered from slow dynamics, and any attempt to speed up the feedback response via tuning may result in an unstable behavior.

  15. 42 CFR 3.208 - Continued protection of patient safety work product.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Continued protection of patient safety work product... GENERAL PROVISIONS PATIENT SAFETY ORGANIZATIONS AND PATIENT SAFETY WORK PRODUCT Confidentiality and Privilege Protections of Patient Safety Work Product § 3.208 Continued protection of patient safety work...

  16. Production of teicoplanin by Actinoplanes teichomyceticus in continuous fermentation

    DEFF Research Database (Denmark)

    Vara, A.G.; Hochkoepple, A.; Nielsen, Jens

    2002-01-01

    Production of the potent antibiotic teicoplanin by Actinoplanes teichomyceticus was studied in batch and in chemostat cultures. It is found that the producing strain deactivates to a non-producing strain named NP-12. This strain is used to find the growth kinetics of the A. teichomyceticus withou...

  17. Stability, resilience and animal production in continuously grazed ...

    African Journals Online (AJOL)

    The Jones-Sandland model, popularly used in southern Africa, may be criticised because it ignores firstly the long-term effects of grazing intensity on the acceptability and productivity of pasture or veld, and secondly possible discontinuities in the animal performance - stocking rate relationship. A mathematical model is ...

  18. A novel fermentor system optimized for continuous production of ...

    African Journals Online (AJOL)

    Jane

    2011-08-29

    Aug 29, 2011 ... polyurethane foam with pore size of 1000 Ǻ. The system has ... enhanced solubility in water (Leathers, 2002). ... 8, pressure gauge ; 9, exhaust ; 9a, exhaust ; 10, extra port for .... pullulan production on the outer walls of unit 'B' into the fermentor. ..... retention period of the fermented broth depending on the.

  19. production of ethyl alcohol from molasses using continuous process

    African Journals Online (AJOL)

    BSN

    Sugar cane molasses from Nigerian Sugar processing factory Bacita were used for ethanol production. A special ethanol resistant yeast strain Sacch:iromyces cerevisiae. (DIST/IPF/90) employed as inoculum was propagated on clarified molasses. Fermentation of clarified molasses to ethanol was brought about at room ...

  20. Pre-aeration of food waste to augment acidogenic process at higher organic load: Valorizing biohydrogen, volatile fatty acids and biohythane.

    Science.gov (United States)

    Sarkar, Omprakash; Venkata Mohan, S

    2017-10-01

    Application of pre-aeration (AS) to waste prior to feeding was evaluated on acidogenic process in a semi-pilot scale biosystem for the production of biobased products (biohydrogen, volatile fatty acids (VFA) and biohythane) from food waste. Oxygen assisted in pre-hydrolysis of waste along with the suppression of methanogenic activity resulting in enhanced acidogenic product formation. AS operation resulted in 97% improvement in hydrogen conversion efficiency (HCE) and 10% more VFA production than the control. Increasing the organic load (OL) of food waste in association with AS application improved the productivity. The application of AS also influenced concentration and composition of fatty acid. Highest fraction of acetic (5.3g/l), butyric (0.7g/l) and propionic acid (0.84g/l) was achieved at higher OL (100g COD/l) with good degree of acidification (DOA). AS strategy showed positive influence on biofuel (biohydrogen and biohythane) production along with the biosynthesis of short chain fatty acids functioning as a low-cost pretreatment strategy in a single stage bioprocess. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Continuous Monitoring of Photolysis Products by Thz Spectroscopy

    Science.gov (United States)

    Omar, Abdelaziz; Cuisset, Arnaud; Mouret, Gaël; Hindle, Francis; Eliet, Sophie; Bocquet, Robin

    2015-06-01

    We demonstrate the potential of THz spectroscopy to monitor the real time evolution of the gas phase concentration of photolysis products and determine the kinetic reaction rate constant. In the primary work, we have chosen to examine the photolysis of formaldehyde (H_2CO). Exposure of H_2CO to a UVB light (250 to 360 nm) in a single pass of 135 cm length cell leads to decomposition via two mechanisms: the radical channel with production of HCO and the molecular channel with production of CO. A commercial THz source (frequency multiplication chain) operating in the range 600-900 GHz was used to detect and quantify the various chemical species as a function of time. Monitoring the concentrations of CO and H_2CO via rotational transitions, allowed the kinetic rate of H_2CO consummation to be obtained, and an estimation of the rate constants for both the molecular and radical photolysis mechanisms. We have modified our experimental setup to increase the sensitivity of the spectrometer and changed sample preparation protocol specifically to quantify the HCO concentration. Acetaldehyde was used as the precursor for photolysis by UVC resulting in the decompositon mechanism can be described by: CH_3CHO+hν→ CH_3 + HCO → CH_4 + CO Frequency modulation of the source and Zeeman modulation is used to achieve the high sensitivity required. Particular attention has been paid to the mercury photosensitization effect that allowed us to increase the HCO production enabling quantification of the monitored radical. We quantify the HCO radical and start a spectroscopic study of the line positions. H. M. Pickett and T. L. Boyd, Chem. Phys. Lett, Vol 58, 446-449, (1978) S. Eliet, A. Cuisset, M Guinet, F. Hindle, G. Mouret, R. Bocquet, and J. Demaison, Journal of Molecular Spectroscopy, Vol 279, 12-15 (2012). G. Mouret, M. Guinet, A. Cuisset, L. Croizé, S. Eliet, R. Bocquet and F. Hindle, Sensors Journal. IEEE, Vol 13, 133 - 138, (2013)

  2. Maintaining ecosystem services through continued livestock production on California rangelands

    Science.gov (United States)

    Barry, S.; Becchetti, T.

    2015-12-01

    Nearly 40% of California is rangeland comprising the largest land type in California and providing forage for livestock, primarily beef cattle. In addition to forage, rangelands provide a host of ecosystem systems services, including habitat for common and endangered species, fire fuels management, pollination services, clean water, viewsheds, and carbon sequestration. Published research has documented that most of these ecosystem services are positively impacted by managed livestock grazing and rancher stewardship. Ranchers typically do not receive any monetary reimbursement for their stewardship in providing these ecosystem services to the public. Markets have been difficult to establish with limited ability to adequately monitor and measure services provided. At the same time, rangelands have been experiencing rapid conversion to urbanization and more profitable and intensive forms of agriculture such as almond and walnut orchards. To prevent further conversion of rangelands and the loss of the services they provide, there needs to be a mechanism to identify and compensate landowners for the value of all products and services being received from rangelands. This paper considers two methods (opportunity cost and avoided cost) to determine the value of Payment for Ecosystem Services (PES) for rangelands. PES can raise the value of rangelands, making them more competitive financially. Real estate values and University of California Cooperative Extension Cost Studies, were used to demonstrate the difference in value (lost opportunity cost) between the primary products of rangelands (livestock production) and the products of the converted rangelands (almond and walnut orchards). Avoided costs for vegetation management and habitat creation and maintenance were used to establish the value of managed grazing. If conversion is to be slowed or stopped and managed grazing promoted to protect the ecosystem services rangelands provide, this value could be compensated through

  3. Potential improvement to a citric wastewater treatment plant using bio-hydrogen and a hybrid energy system

    Science.gov (United States)

    Zhi, Xiaohua; Yang, Haijun; Berthold, Sascha; Doetsch, Christian; Shen, Jianquan

    Treatment of highly concentrated organic wastewater is characterized as cost-consuming. The conventional technology uses the anaerobic-anoxic-oxic process (A 2/O), which does not produce hydrogen. There is potential for energy saving using hydrogen utilization associated with wastewater treatment because hydrogen can be produced from organic wastewater using anaerobic fermentation. A 50 m 3 pilot bio-reactor for hydrogen production was constructed in Shandong Province, China in 2006 but to date the hydrogen produced has not been utilized. In this work, a technical-economic model based on hydrogen utilization is presented and analyzed to estimate the potential improvement to a citric wastewater plant. The model assesses the size, capital cost, annual cost, system efficiency and electricity cost under different configurations. In a stand-alone situation, the power production from hydrogen is not sufficient for the required load, thus a photovoltaic array (PV) is employed as the power supply. The simulated results show that the combination of solar and bio-hydrogen has a much higher cost compared with the A 2/O process. When the grid is connected, the system cost achieved is 0.238 US t -1 wastewater, which is lower than 0.257 US t -1 by the A 2/O process. The results reveal that a simulated improvement by using bio-hydrogen and a FC system is effective and feasible for the citric wastewater plant, even when compared to the current cost of the A 2/O process. In addition, lead acid and vanadium flow batteries were compared for energy storage service. The results show that a vanadium battery has lower cost and higher efficiency due to its long lifespan and energy efficiency. Additionally, the cost distribution of components shows that the PV dominates the cost in the stand-alone situation, while the bio-reactor is the main cost component in the parallel grid.

  4. Process for continuous production of metallic uranium and uranium alloys

    Science.gov (United States)

    Hayden, Jr., Howard W.; Horton, James A.; Elliott, Guy R. B.

    1995-01-01

    A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO.sub.3), or any other substantially stable uranium oxide, to form the uranium dioxide (UO.sub.2). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl.sub.4), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation.

  5. Process for continuous production of metallic uranium and uranium alloys

    Science.gov (United States)

    Hayden, H.W. Jr.; Horton, J.A.; Elliott, G.R.B.

    1995-06-06

    A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO{sub 3}), or any other substantially stable uranium oxide, to form the uranium dioxide (UO{sub 2}). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl{sub 4}), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation. 4 figs.

  6. A conceptual framework on the role of creativity in sustaining continuous innovation in new product development

    OpenAIRE

    Bélanger, Souni; Veilleux, Sophie; Tremblay, Maripier

    2016-01-01

    If creativity and innovation are viewed as assets in any business, they represent for some a key survival factor imposed by their industry on a daily basis. In such a context of continuous innovation, the pace of innovation is accelerated. This article focuses on how creativity helps sustain continuous innovation in new product development. We develop a conceptual framework that highlights the key factors that lead to continuous new product development: information management, ...

  7. DEVELOPMENT OF CONTINUOUS SOLVENT EXTRACTION PROCESSES FOR COAL DERIVED CARBON PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    Elliot B. Kennel; Stephen P. Carpenter; Dady Dadyburjor; Manoj Katakdaunde; Liviu Magean; Peter G. Stansberry; Alfred H. Stiller; John W. Zondlo

    2005-06-08

    The purpose of this DOE-funded effort is to develop continuous processes for solvent extraction of coal for the production of carbon products. These carbon products include materials used in metals smelting, especially in the aluminum and steel industries, as well as porous carbon structural material referred to as ''carbon foam'' and carbon fibers. During this reporting period, efforts have focused on the development of continuous processes for hydrogenation as well as continuous production of carbon foam and coke.

  8. DEVELOPMENT OF CONTINUOUS SOLVENT EXTRACTION PROCESSES FOR COAL DERIVED CARBON PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    Elliot B. Kennel; Stephen P. Carpenter; Dady Dadyburjor; Manoj Katakdaunde; Liviu Magean; Madhavi Nallani-Chakravartula; Peter G. Stansberry; Alfred H. Stiller; John W. Zondlo

    2006-03-27

    The purpose of this DOE-funded effort is to develop continuous processes for solvent extraction of coal for the production of carbon products. These carbon products include materials used in metals smelting, especially in the aluminum and steel industries, as well as porous carbon structural material referred to as ''carbon foam'' and carbon fibers. During this reporting period, efforts have focused on the development of continuous processes for hydrogenation as well as continuous production of carbon foam and coke.

  9. A COMBINED REACTION/PRODUCT RECOVERY PROCESS FOR THE CONTINUOUS PRODUCTION OF BIODIESEL

    Energy Technology Data Exchange (ETDEWEB)

    Birdwell, J.F., Jr.; McFarlane, J.; Schuh, D.L.; Tsouris, C; Day, J.N. (Nu-Energie, LLC); Hullette, J.N. (Nu-Energie, LLC)

    2009-09-01

    Oak Ridge National Laboratory (ORNL) and Nu-Energie, LLC entered into a Cooperative Research And Development Agreement (CRADA) for the purpose of demonstrating and deploying a novel technology for the continuous synthesis and recovery of biodiesel from the transesterification of triglycerides. The focus of the work was the demonstration of a combination Couette reactor and centrifugal separator - an invention of ORNL researchers - that facilitates both product synthesis and recovery from reaction byproducts in the same apparatus. At present, transesterification of triglycerides to produce biodiesel is performed in batch-type reactors with an excess of a chemical catalyst, which is required to achieve high reactant conversions in reasonable reaction times (e.g., 1 hour). The need for long reactor residence times requires use of large reactors and ancillary equipment (e.g., feed and product tankage), and correspondingly large facilities, in order to obtain the economy of scale required to make the process economically viable. Hence, the goal of this CRADA was to demonstrate successful, extended operation of a laboratory-scale reactor/separator prototype to process typical industrial reactant materials, and to design, fabricate, and test a production-scale unit for deployment at the biodiesel production site. Because of its ease of operation, rapid attainment of steady state, high mass transfer and phase separation efficiencies, and compact size, a centrifugal contactor was chosen for intensification of the biodiesel production process. The unit was modified to increase the residence time from a few seconds to minutes*. For this application, liquid phases were introduced into the reactor as separate streams. One was composed of the methanol and base catalyst and the other was the soy oil used in the experiments. Following reaction in the mixing zone, the immiscible glycerine and methyl ester products were separated in the high speed rotor and collected from separate

  10. A COMBINED REACTION/PRODUCT RECOVERY PROCESS FOR THE CONTINUOUS PRODUCTION OF BIODIESEL

    International Nuclear Information System (INIS)

    Birdwell, J.F. Jr.; McFarlane, J.; Schuh, D.L.; Tsouris, C.; Day, J.N.; Hullette, J.N.

    2009-01-01

    Oak Ridge National Laboratory (ORNL) and Nu-Energie, LLC entered into a Cooperative Research And Development Agreement (CRADA) for the purpose of demonstrating and deploying a novel technology for the continuous synthesis and recovery of biodiesel from the transesterification of triglycerides. The focus of the work was the demonstration of a combination Couette reactor and centrifugal separator - an invention of ORNL researchers - that facilitates both product synthesis and recovery from reaction byproducts in the same apparatus. At present, transesterification of triglycerides to produce biodiesel is performed in batch-type reactors with an excess of a chemical catalyst, which is required to achieve high reactant conversions in reasonable reaction times (e.g., 1 hour). The need for long reactor residence times requires use of large reactors and ancillary equipment (e.g., feed and product tankage), and correspondingly large facilities, in order to obtain the economy of scale required to make the process economically viable. Hence, the goal of this CRADA was to demonstrate successful, extended operation of a laboratory-scale reactor/separator prototype to process typical industrial reactant materials, and to design, fabricate, and test a production-scale unit for deployment at the biodiesel production site. Because of its ease of operation, rapid attainment of steady state, high mass transfer and phase separation efficiencies, and compact size, a centrifugal contactor was chosen for intensification of the biodiesel production process. The unit was modified to increase the residence time from a few seconds to minutes*. For this application, liquid phases were introduced into the reactor as separate streams. One was composed of the methanol and base catalyst and the other was the soy oil used in the experiments. Following reaction in the mixing zone, the immiscible glycerine and methyl ester products were separated in the high speed rotor and collected from separate

  11. Optimal policies for Production-Clearing Systems under Continuous-Review

    NARCIS (Netherlands)

    Germs, R.; Foreest, van Nicky D.; Kilic, Onur A.

    2016-01-01

    In this paper, we consider a production-clearing system with compound Poisson demand under continuous review. The production facility produces one type of item without stopping and at a constant rate, and stores the product into a buffer to meet future demand. To prevent high inventory levels, a

  12. Trends of bio-hydrogen research and development in Europe. Report for the Research Institute of Innovative Technology for the Earth (RITE), Tokyo, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Huesing, B.

    1997-03-01

    Research into applied aspects of biological hydrogen production is carried out on a much lower level in Europe than basic hydrogenase research. However, the screening for good H{sub 2} producers, their cultivation, and the development of optimised culture and bioreactor systems has never been a strength in Europe. Although there are a few good groups in Europe major contributions in this field traditionally come from countries outside Europe. However, in the nineties a special application-oriented research subfield has begun to evolve in Europe: the use of genetic enginering to rationally optimise H{sub 2} producing organisms. The most important players who focus on green algae, cyanobacteria, and purple bacteria can be found in Germany, France, and Sweden. In European biohydrogen research, a large and diverse variety of organisms is investigated. Among the organisms most thoroughly studied are Alcaligenes eutrophus, Escherichia coli, Rhodobacter capsulatus, sulfate-reducing bacteria, and methanogenic bacteria. Moreover, a leading position has been obtained with respect to molecular genetics of green algae and cyanobacteria, albeit on a low level. The fact that such a broad range of diverse organisms is studied has advantages and disadvantages. A positive aspect is that the multitude of different approaches had led to several unexpected results which had otherwise been overlooked. On the other hand, an obvious link to biohydrogen production is often lacking. Moreover, there are many 'me-too' approaches and results in which previous findings are only reproduced for another organism as well. (orig.)

  13. Effects of a tannin-rich legume (Onobrychis viciifolia on in vitro ruminal biohydrogenation and fermentation

    Directory of Open Access Journals (Sweden)

    Gonzalo Hervás

    2016-03-01

    Full Text Available There is still controversy surrounding the ability of tannins to modulate the ruminal biohydrogenation (BH of fatty acids (FA and improve the lipid profile of milk or meat without conferring a negative response in the digestive utilization of the diet. Based on this, an in vitro trial using batch cultures of rumen microorganisms was performed to compare the effects of two legume hays with similar chemical composition but different tannin content, alfalfa and sainfoin (Onobrychis viciifolia, on the BH of dietary unsaturated FA and on the ruminal fermentation. The first incubation substrate, alfalfa, was practically free of tannins, while the second, sainfoin, contained 3.5% (expressed as tannic acid equivalents. Both hays were enriched with sunflower oil as a source of unsaturated FA. Most results of the lipid composition analysis (e.g., greater concentrations of 18:2n-6, cis-9 18:1 or total polyunsaturated FA in sainfoin incubations showed the ability of this tannin-containing legume to inhibit the BH process. However, no significant differences were detected in the accumulation of cis-9 trans-11 conjugated linoleic acid, and variations in trans-11 18:1 and trans-11 cis-15 18:2 did not follow a regular pattern. Regarding the rumen fermentation, gas production, ammonia concentration and volatile FA production were lower in the incubations with sainfoin (-17, -23 and -11%, respectively. Thus, although this legume was able to modify the ruminal BH, which might result in improvements in the meat or milk lipid profile, the present results were not as promising as expected or as obtained before with other nutritional strategies.

  14. Effects of a tannin-rich legume (Onobrychis viciifolia) on in vitro ruminal biohydrogenation and fermentation

    Energy Technology Data Exchange (ETDEWEB)

    González, M.A.; Peláez, F.R.; Martínez, A.L.; Avilés, C.; Peña, F.

    2016-11-01

    There is still controversy surrounding the ability of tannins to modulate the ruminal biohydrogenation (BH) of fatty acids (FA) and improve the lipid profile of milk or meat without conferring a negative response in the digestive utilization of the diet. Based on this, an in vitro trial using batch cultures of rumen microorganisms was performed to compare the effects of two legume hays with similar chemical composition but different tannin content, alfalfa and sainfoin (Onobrychis viciifolia), on the BH of dietary unsaturated FA and on the ruminal fermentation. The first incubation substrate, alfalfa, was practically free of tannins, while the second, sainfoin, contained 3.5% (expressed as tannic acid equivalents). Both hays were enriched with sunflower oil as a source of unsaturated FA. Most results of the lipid composition analysis (e.g., greater concentrations of 18:2n-6, cis-9 18:1 or total polyunsaturated FA in sainfoin incubations) showed the ability of this tannin-containing legume to inhibit the BH process. However, no significant differences were detected in the accumulation of cis-9 trans-11 conjugated linoleic acid, and variations in trans-11 18:1 and trans-11 cis-15 18:2 did not follow a regular pattern. Regarding the rumen fermentation, gas production, ammonia concentration and volatile FA production were lower in the incubations with sainfoin (‒17, ‒23 and ‒11%, respectively). Thus, although this legume was able to modify the ruminal BH, which might result in improvements in the meat or milk lipid profile, the present results were not as promising as expected or as obtained before with other nutritional strategies. (Author)

  15. Ruminal biohydrogenation kinetics of defatted flaxseed and sunflower is affected by heat treatment

    DEFF Research Database (Denmark)

    Lashkari, Saman; Hymøller, Lone; Jensen, Søren Krogh

    2017-01-01

    The effect of heat treatment on biohydrogenation of linoleic acid (LA) and linolenic acid (LNA) and formation of stearic acid (SA), cis-9, trans-11 conjugated LA (CLA), trans-10, cis-12 CLA and trans-vaccenic acid (VA) was studied in in vitro incubations with diluted rumen fluid as inoculum...

  16. Orodispersible films: Product transfer from lab-scale to continuous manufacturing.

    Science.gov (United States)

    Thabet, Yasmin; Breitkreutz, Joerg

    2018-01-15

    Orodispersible films have been described as new beneficial dosage forms for special patient populations. Due to various production settings, different requirements on film formulations are required for non- continuous and continuous manufacturing. In this study, a continuous coating machine was qualified in regards of the process conditions for film compositions and their effects on the formed films. To investigate differences between both manufacturing processes, various film formulations of hydrochlorothiazide and hydroxypropylcellulose (HPC) or hydroxypropylmethycellulose (HPMC) as film formers were produced and the resulting films were characterized. The qualification of the continuously operating coating machine reveals no uniform heat distribution during drying. Coating solutions for continuous manufacturing should provide at least a dynamic viscosity of 1 Pa*s (wet film thickness of 500 μm, velocity of 15.9 cm/min). HPC films contain higher residuals of ethanol or acetone in bench-scale than in continuous production mode. Continuous production lead to lower drug content of the films. All continuously produced films disintegrate within less than 30 s. There are observed significant effects of the production process on the film characteristics. When transferring film manufacturing from lab-scale to continuous mode, film compositions, processing conditions and suitable characterization methods have to be carefully selected and adopted. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Two-phase anaerobic digestion of mixed waste streams to separate generation of bio-hydrogen and bio-methane

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, Z.; Horam, N.J. [Leeds Univ. (United Kingdom). School of Civil Engineering

    2010-07-01

    The purpose of this study was to investigate the net energy potential of single stage mesophilic reactor and two phase mesophilic reactor (hydrogeniser followed by methaniser) using the mix of process industrial food waste (IFW) and sewage sludge (SS). Two-phase reactor efficiency was analysed based on individual optimum influent/environmental (C:N and pH) and reactor/engineering (HRT and OLR) conditions achieved using the batch and continuous reactor study for the hydrogen and methane. Optimum C:N 20 and pH 5.5{+-}0.5 was observed using the Bio-H{sub 2} potential (BHP) and C:N 15 and pH 6.5{+-}0.3 for the biochemical methane potential (BMP) test. The maximum hydrogen content of 47% (v/v) was achieved using OLR 6 g VS/L/d and HRT of 5 days. Increase in hydrogen yield was noticed with consistent decrease in OLR. The volatile solids (VS) removal and hydrogen yield was observed in range 41.3 to 47% and 112.3 to 146.7 mL/ gVS{sub removed}. The specific hydrogen production rate improved at low OLR, 0.2 to 0.4 L/(L.d) using OLR 7.1 and 6 g VS/L/d respectively was well corroborated comparable to previous reported results at OLR 6 gVS/L/d using the enriched carbohydrate waste stream in particular to food wastes. A significant increase in VFA concentrations were noticed shifting OLR higher from 6 g VS/L/d thereby unbalancing the reactor pH and the biogas yield respectively. In similar, maximum methane content of 70% (v/v) was achieved using OLR of 3.3 gVS/L/d and HRT of 10 days. Slight decrease in methane content was noticed thereby increasing HRT to 12 and 15 days respectively. The volatile solids (VS) removal and specific methane production rate was observed in range 57.6 to 68.7 and 0.22 to 1.19 L/(L.d). The specific methane production potential improved thereby reducing the HRT and optimum yield was recorded as 476.6 mL/gVS{sub removed} using OLR 3.3 gVS/L/d. The energy potential of optimum condition in single stage hydorgeniser is 2.27 MW/tonne VS{sub fed}. Using the

  18. Production of specific-structured lipids by enzymatic interesterification in a pilot continuous enzyme bed reactor

    DEFF Research Database (Denmark)

    Xu, Xuebing; Balchen, Steen; Høy, Carl-Erik

    1998-01-01

    Production of specific-structured lipids (interesterified lipids with a specific structure) by enzymatic interesterification was carried out in a continuous enzyme bed pilot scale reactor. Commercial immobilized lipase (Lipozyme IM) was used and investigations of acyl migration, pressure drop...

  19. Development of continuous pharmaceutical production processes supported by process systems engineering methods and tools

    DEFF Research Database (Denmark)

    Gernaey, Krist; Cervera Padrell, Albert Emili; Woodley, John

    2012-01-01

    The pharmaceutical industry is undergoing a radical transition towards continuous production processes. Systematic use of process systems engineering (PSE) methods and tools form the key to achieve this transition in a structured and efficient way.......The pharmaceutical industry is undergoing a radical transition towards continuous production processes. Systematic use of process systems engineering (PSE) methods and tools form the key to achieve this transition in a structured and efficient way....

  20. Safety research in the field of energy production. Plan for continued Nordic projects

    Energy Technology Data Exchange (ETDEWEB)

    Ahlstroem, P E [Statens Vattenfallsverk, Stockholm (Sweden); Berg, J [Institutt for Atomenergi, Kjeller (Norway); Eckered, T [Statens Kaernkraftinspektion, Stockholm (Sweden)

    1980-01-01

    NGS, an ad hoc group of the Nordic Co-ordination Committee for Atomic Energy, has prepared this survey of proposed cooperative projects as a continuation of previous projects. New areas to be given priority are:- reactor safety, environmental effects in energy production and human reliability. Continued projects are:- quality assurance, radioactive waste and radioecology. (JIW)

  1. Continuous counter-current chromatography for capture and polishing steps in biopharmaceutical production.

    Science.gov (United States)

    Steinebach, Fabian; Müller-Späth, Thomas; Morbidelli, Massimo

    2016-09-01

    The economic advantages of continuous processing of biopharmaceuticals, which include smaller equipment and faster, efficient processes, have increased interest in this technology over the past decade. Continuous processes can also improve quality assurance and enable greater controllability, consistent with the quality initiatives of the FDA. Here, we discuss different continuous multi-column chromatography processes. Differences in the capture and polishing steps result in two different types of continuous processes that employ counter-current column movement. Continuous-capture processes are associated with increased productivity per cycle and decreased buffer consumption, whereas the typical purity-yield trade-off of classical batch chromatography can be surmounted by continuous processes for polishing applications. In the context of continuous manufacturing, different but complementary chromatographic columns or devices are typically combined to improve overall process performance and avoid unnecessary product storage. In the following, these various processes, their performances compared with batch processing and resulting product quality are discussed based on a review of the literature. Based on various examples of applications, primarily monoclonal antibody production processes, conclusions are drawn about the future of these continuous-manufacturing technologies. Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Design and operation of a filter reactor for continuous production of a selected pharmaceutical intermediate

    DEFF Research Database (Denmark)

    Christensen, Kim Müller; Pedersen, Michael Jønch; Dam-Johansen, Kim

    2012-01-01

    in tetrahydrofuran solvent. The use of the filter reactor design was explored by examining the transferability of a synthesis step in a present full-scale semi-batch pharmaceutical production into continuous processing. The main advantages of the new continuous minireactor system, compared to the conventional semi...

  3. Selective fermentation of carbohydrate and protein fractions of Scenedesmus, and biohydrogenation of its lipid fraction for enhanced recovery of saturated fatty acids.

    Science.gov (United States)

    Lai, YenJung Sean; Parameswaran, Prathap; Li, Ang; Aguinaga, Alyssa; Rittmann, Bruce E

    2016-02-01

    Biofuels derived from microalgae have promise as carbon-neutral replacements for petroleum. However, difficulty extracting microalgae-derived lipids and the co-extraction of non-lipid components add major costs that detract from the benefits of microalgae-based biofuel. Selective fermentation could alleviate these problems by managing microbial degradation so that carbohydrates and proteins are hydrolyzed and fermented, but lipids remain intact. We evaluated selective fermentation of Scenedesmus biomass in batch experiments buffered at pH 5.5, 7, or 9. Carbohydrates were fermented up to 45% within the first 6 days, protein fermentation followed after about 20 days, and lipids (measured as fatty acid methyl esters, FAME) were conserved. Fermentation of the non-lipid components generated volatile fatty acids, with acetate, butyrate, and propionate being the dominant products. Selective fermentation of Scenedesmus biomass increased the amount of extractable FAME and the ratio of FAME to crude lipids. It also led to biohydrogenation of unsaturated FAME to more desirable saturated FAME (especially to C16:0 and C18:0), and the degree of saturation was inversely related to the accumulation of hydrogen gas after fermentation. Moreover, the microbial communities after selective fermentation were enriched in bacteria from families known to perform biohydrogenation, i.e., Porphyromonadaceae and Ruminococcaceae. Thus, this study provides proof-of-concept that selective fermentation can improve the quantity and quality of lipids that can be extracted from Scenedesmus. © 2015 Wiley Periodicals, Inc.

  4. Chemoselective biohydrogenation of chalcone (2Ε)-3-(1,3-benzodioxole-5-yl)-1-phenyl-2-propen-1-one mediated by baker yeasts immobilized in polymeric supports

    International Nuclear Information System (INIS)

    Mundstock, Flavia L.S.; Silva, Vanessa D.; Nascimento, Maria da G.

    2009-01-01

    In this study, the yeast Saccharomyces cerevisiae, baker's yeast (BY) was immobilized in poly(ethylene oxide) (PEO), poly(vinyl alcohol) (PVA), sodium caseinate (SC), gelatin (G) films and in agar (A) and gelatin (G) gels, and used as a biocatalyst in the biohydrogenation reaction of (2Ε)-3-(1,3-benzodioxyl-5-yl)-1-phenyl-2-propen-1-one (1). The transformation of (1) into the corresponding dehydro chalcone (2) through biohydrogenation reactions was carried out in n-hexane at 25 or 35 deg C, for 4-48 h reaction. The product conversion, under different experimental conditions, was evaluated by hydrogen nuclear magnetic resonance, 1 H NMR.The highest conversion degrees were achieved using BY immobilized in agar gel, (29-47%), depending also on the temperature. Using BY immobilized in PEO, PVA, SC and G films, the conversion into (2) was lower (0-21%). The results show the feasibility of the use of BY immobilized in polymeric materials to reduce a,b-unsaturated carbonyl compounds. (author)

  5. Microfluidic Platform for the Continuous Production and Characterization of Multilamellar Vesicles

    DEFF Research Database (Denmark)

    Ghazal, Aghiad; Gontsarik, Mark; Kutter, Jörg P.

    2017-01-01

    A microfluidic platform combined with synchrotron small-angle X-ray scattering (SAXS) was used for monitoring the continuous production of multilamellar vesicles (MLVs). Their production was fast and started to evolve within less than 0.43 s of contact between the lipids and the aqueous phase...

  6. Enteric methane production and ruminal fermentation from forage brassica diets fed in continuous culture

    Science.gov (United States)

    Brassicas provide forage for livestock during the late fall when traditional perennial cool-season forages are not productive. However, little research exists on ruminal fermentation and methane(CH4) production of brassicas fed as forage. A continuous culture fermentor system was used to assess nutr...

  7. Enteric methane production and ruminal fermentation of forage brassica diets fed in continuous culture

    Science.gov (United States)

    The aim of the current study was to determine nutrient digestibility, VFA production, N metabolism, and CH4 production of canola (Brassica napus L.), rapeseed (B. napus L.), turnip (B. rapa L.), and annual ryegrass (Lolium multiflorum Lam.) fed with orchardgrass (Dactylis glomerata L.) in continuous...

  8. 77 FR 34938 - Certain Tin Mill Products From Japan: Continuation of Antidumping Duty Order

    Science.gov (United States)

    2012-06-12

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-588-854] Certain Tin Mill Products... duty order on certain tin mill products from Japan would likely lead to continuation or recurrence of...: Background On August 28, 2000, the Department published the antidumping duty order on certain tin mill...

  9. Large-scale enzymatic production of natural flavour esters in organic solvent with continuous water removal.

    Science.gov (United States)

    Gubicza, L; Kabiri-Badr, A; Keoves, E; Belafi-Bako, K

    2001-11-30

    A new, large-scale process was developed for the enzymatic production of low molecular weight flavour esters in organic solvent. Solutions for the elimination of substrate and product inhibitions are presented. The excess water produced during the process was continuously removed by hetero-azeotropic distillation and esters were produced at yields of over 90%.

  10. 14 CFR 183.63 - Continuing requirements: Products, parts or appliances.

    Science.gov (United States)

    2010-01-01

    ... appliances. 183.63 Section 183.63 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Designation Authorization § 183.63 Continuing requirements: Products, parts or appliances. For any approval or certificate for a product, part or appliance issued under the authority of this subpart, or under the...

  11. Design and operation of a continuous integrated monoclonal antibody production process.

    Science.gov (United States)

    Steinebach, Fabian; Ulmer, Nicole; Wolf, Moritz; Decker, Lara; Schneider, Veronika; Wälchli, Ruben; Karst, Daniel; Souquet, Jonathan; Morbidelli, Massimo

    2017-09-01

    The realization of an end-to-end integrated continuous lab-scale process for monoclonal antibody manufacturing is described. For this, a continuous cultivation with filter-based cell-retention, a continuous two column capture process, a virus inactivation step, a semi-continuous polishing step (twin-column MCSGP), and a batch-wise flow-through polishing step were integrated and operated together. In each unit, the implementation of internal recycle loops allows to improve the performance: (a) in the bioreactor, to simultaneously increase the cell density and volumetric productivity, (b) in the capture process, to achieve improved capacity utilization at high productivity and yield, and (c) in the MCSGP process, to overcome the purity-yield trade-off of classical batch-wise bind-elute polishing steps. Furthermore, the design principles, which allow the direct connection of these steps, some at steady state and some at cyclic steady state, as well as straight-through processing, are discussed. The setup was operated for the continuous production of a commercial monoclonal antibody, resulting in stable operation and uniform product quality over the 17 cycles of the end-to-end integration. The steady-state operation was fully characterized by analyzing at the outlet of each unit at steady state the product titer as well as the process (HCP, DNA, leached Protein A) and product (aggregates, fragments) related impurities. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1303-1313, 2017. © 2017 American Institute of Chemical Engineers.

  12. Towards continuous enzyme-catalysed processes for the production of biodiesel

    DEFF Research Database (Denmark)

    Nordblad, Mathias; Pedersen, Anders Kristian; Meyland, Lene Have

    The application of lipases in the production of biodiesel can find several roles: in pretreating high FFA oils via esterification, transesterification for converting oil to biodiesel and polishing via esterification to ensure the product is within specification. In all these cases the potential...... size of the process plants, suggest that continuous operation would be highly beneficial due to the economies of scale. To investigate this, we have examined both oil pretreatment via esterification and biodiesel production via transesterification in batch stirred tank reactors (BSTRs), continuous...

  13. Organizational learning perspective on continuous improvement and innovation in product realization

    DEFF Research Database (Denmark)

    Møller, Christina Villefrance

    with cross-functional collaboration in solving problems that subsequently restraining continuous improvement and innovation (CII) in product realization. This research project apply an organizational learning perspective on cross-functional problem solving in product realization processes. The research...... project has two main objectives, first to develop and test a CIIprogram that integrates cross-functional work practices into product realization. The second objective is to enhance understanding of organizational learning processes in cross-functional and multilevel settings within manufacturing....

  14. Evidence for the Initial Steps of DHA Biohydrogenation by Mixed Ruminal Microorganisms from Sheep Involves Formation of Conjugated Fatty Acids.

    Science.gov (United States)

    Aldai, Noelia; Delmonte, Pierluigi; Alves, Susana P; Bessa, Rui J B; Kramer, John K G

    2018-01-31

    Incubation of DHA with sheep rumen fluid resulted in 80% disappearance in 6 h. The products were analyzed as their fatty acid (FA) methyl esters by GC-FID on SP-2560 and SLB-IL111 columns. The GC-online reduction × GC and GC-MS techniques demonstrated that all DHA metabolites retained the C22 structure (no evidence of chain-shortening). Two new transient DHA products were identified: mono-trans methylene interrupted-DHA and monoconjugated DHA (MC-DHA) isomers. Identification of MC-DHA was confirmed by their predicted elution using equivalent chain length differences from C18 FA, their molecular ions, and the 22:5 products formed which were the most abundant at 6 h. The 22:5 structures were established by fragmentation of their 4,4-dimethyloxazoline derivatives, and all 22:5 products contained an isolated double bond, suggesting formation via MC-DHA. The most abundant c4,c7,c10,t14,c19-22:5 appeared to be formed by unknown isomerases. Results suggest that the initial biohydrogenation of DHA was analogous to that of C18 FA.

  15. OPTIMASI PRODUKSI ENZIMATIS DIASILGLISEROL MELALUI GLISEROLISIS KONTINU [Optimization of Enzymatic Diacylglycerol Production through Continuous Glycerolysis

    Directory of Open Access Journals (Sweden)

    Tri-Panji*

    2014-06-01

    Full Text Available Diacylglycerol (DAG produced from crude palm oil (CPO is one of the healthy oils that can be consumed for daily human diet. DAG production in Indonesia is constrained by the high cost of the mostly imported lipase. To overcome this problem, research of DAG production has been carried out using crude extracts of lipase produced by local species of fungi Rhizopus oryzae. This study aims to develop a continuous process of enzymatic glycerolysis of CPO for DAG production; to establish optimum conditions of DAG production which includes flow rate of CPO and glycerolysis time; and to test the performance of lipase from the local mold R. oryzae in catalyzing continuous process of glycerolysis for the production of DAG. Lipase isolation was carried out by acetone precipitation and lipase was used as a catalyst in the continuous glycerolysis process. The glycerolysis was conducted by reacting CPO with glycerol continuously at various time periods. The optimum condition of automatic continuous glycerolysis process was achieved at a CPO flow rate of 3 mL/min with a glycerolysis time at the 18 cycles (9 hours. The conversion of DAG was 29%. The performance of lipase was proven to remain stable up to 3 times changes of CPO substrate for 9 hours of glycerolysis process with the best condition at the 3 cycles and can improved conversion of DAG until 37%.

  16. Study on improvement of continuous hydrogen production by photosynthetic biofilm in interior illuminant reactor.

    Science.gov (United States)

    Liu, Wenhui; Yuan, Linjiang; Wei, Bo

    2016-09-01

    In the present study, a new type of interior optical fiber illuminating reactor was developed for H2 production to solve the problem of luminous intensity attenuation at the center portion of a reactor, and an immobilization technique was used to enhance the stability of a continuous hydrogen production process with attached photosynthetic bacteria, using glucose as a sole carbon substrate for the indigenous photosynthetic bacteria (PSB) Rhodopseudomonas palustris SP-6. Results of the experiments showed that the interior optical fiber illuminating reactor produces H2 more efficiently and productively than the exterior light source reactor, with the cumulative H2 production, the maximum H2 production rate and H2 yield increased by 813ml, 11.3ml l-1 h-1 and 22.3%, respectively. The stability of the product of continuous hydrogen was realized by immobilizing PSB on the surface of powder active carbon(PAC). After adding the dosage of 2.0g l-1 PAC, the continuous steady operation of H2 production gave a high H2 yield of 1.398 mol H2 mol-1 glucose and an average H2 production rate of 35.1ml l-1 h-1 illuminating with a single interior optical fiber light source. Meanwhile, a higher H2 yield of 1.495 mol H2 mol-1 glucose and an average H2 production rate of 38.7ml l-1 h-1 were attained illuminating with a compound lamp in the continuous H2 production for 20 days.

  17. Multi-stage high cell continuous fermentation for high productivity and titer.

    Science.gov (United States)

    Chang, Ho Nam; Kim, Nag-Jong; Kang, Jongwon; Jeong, Chang Moon; Choi, Jin-dal-rae; Fei, Qiang; Kim, Byoung Jin; Kwon, Sunhoon; Lee, Sang Yup; Kim, Jungbae

    2011-05-01

    We carried out the first simulation on multi-stage continuous high cell density culture (MSC-HCDC) to show that the MSC-HCDC can achieve batch/fed-batch product titer with much higher productivity to the fed-batch productivity using published fermentation kinetics of lactic acid, penicillin and ethanol. The system under consideration consists of n-serially connected continuous stirred-tank reactors (CSTRs) with either hollow fiber cell recycling or cell immobilization for high cell-density culture. In each CSTR substrate supply and product removal are possible. Penicillin production is severely limited by glucose metabolite repression that requires multi-CSTR glucose feeding. An 8-stage C-HCDC lactic acid fermentation resulted in 212.9 g/L of titer and 10.6 g/L/h of productivity, corresponding to 101 and 429% of the comparable lactic acid fed-batch, respectively. The penicillin production model predicted 149% (0.085 g/L/h) of productivity in 8-stage C-HCDC with 40 g/L of cell density and 289% of productivity (0.165 g/L/h) in 7-stage C-HCDC with 60 g/L of cell density compared with referring batch cultivations. A 2-stage C-HCDC ethanol experimental run showed 107% titer and 257% productivity of the batch system having 88.8 g/L of titer and 3.7 g/L/h of productivity. MSC-HCDC can give much higher productivity than batch/fed-batch system, and yield a several percentage higher titer as well. The productivity ratio of MSC-HCDC over batch/fed-batch system is given as a multiplication of system dilution rate of MSC-HCDC and cycle time of batch/fed-batch system. We suggest MSC-HCDC as a new production platform for various fermentation products including monoclonal antibody.

  18. Feasibility of Continuous Frying System to Improve the Quality Indices of Palm Olein for the Production of Extruded Product.

    Science.gov (United States)

    Ahmad Tarmizi, Azmil Haizam; Ahmad, Karimah

    2015-01-01

    Comparative frying studies on the processing of extruded product were conducted under intermittent and continuous frying conditions using two separate frying systems, i.e batch and pilot scale continuous fryers, respectively. Thermal resistance of palm olein were assessed for a total of 5 days of frying operation at 155°C - the unconventional frying temperature gave the product moisture content of 3% after intermittent and continuous frying for 2.5 min and 2 min, respectively. The formation of free fatty acid in palm olein in the case of intermittent frying was more than 2-fold higher compared to its counterpart (0.66%). Smoke point inversely evolved with oil acidity: the value dropped progressively from 215 to 177°C and from 219 to 188°C when extruded product was intermittently and continuously fried, respectively. In the light of induction period, repeated frying exhibited a gradual decrease in the value after 5 days of frying (12.2 h). Interestingly, continuous frying gave somewhat similar induction period, as demonstrated by fresh palm olein, across frying time. Frying at lower temperature, to some extent, provides opportunity for palm olein to retain 74% of its initial vitamin E during continuous frying. This benefit, however, is somehow denied when extruded product was processed under intermittent frying conditions--only 27% of vitamin E was remained at the end of frying session. Regardless of frying protocols, transient in polar compounds was minimal and hence comparable. The colour in the case of continuous frying appeared to be darker due to higher degree of oil utilisation for frying. The data obtained will provide useful information for food processors on how palm olein behaves when frying is undertaken under different frying protocols.

  19. Process development of continuous glycerolysis in an immobilized enzyme-packed reactor for industrial monoacylglycerol production

    DEFF Research Database (Denmark)

    Damstrup, Marianne; Kiil, Søren; Jensen, Anker Degn

    2007-01-01

    Continuous and easily operated glycerolysis was studied in different lipase-packed columns to evaluate the most potential process set-ups for industrial monoacylglycerol (MAG) production. Practical design-related issues such as enzyme-filling degree, required reaction time, mass transfer investig......Continuous and easily operated glycerolysis was studied in different lipase-packed columns to evaluate the most potential process set-ups for industrial monoacylglycerol (MAG) production. Practical design-related issues such as enzyme-filling degree, required reaction time, mass transfer...

  20. Scientific production in CBCE/CONBRACE: the continuing education from 2007 to 2013 in focus

    Directory of Open Access Journals (Sweden)

    Deiva Mara Delfini Batista

    2015-11-01

    Full Text Available This study, qualitative and documentary character, aimed to analyze the scientific production about continuing education of teachers between the years 2007 and 2013, from the GTT "Teachers Training and the World of Work" of the Brazilian Sports Science College. We identified 49 papers about the issue, which were categorized into different groups based on their approaches and features. The results portray the existence of systematic scientific production about continuing education, and that is articulate with the reality of Brazilian graduate. However, some categories showed little representation, pointing challenges to be faced, requiring more research about the issue.

  1. Improvement production of bacterial cellulose by semi-continuous process in molasses medium.

    Science.gov (United States)

    Cakar, Fatih; Ozer, Işılay; Aytekin, A Özhan; Sahin, Fikrettin

    2014-06-15

    Bacterial cellulose (BC) has unique properties such as structural, functional, physical and chemical. The mass production of BC for industrial application has recently become attractive to produce more economical and high productive cellulose. In this study, to improve the productivity of bacterial cellulose (BC), BC production by Gluconacetobacter xylinus FC01 was investigated in molasses medium with static semi-continuous operation mode. Cell dry weight, polysaccharide, sugar and cellulose concentrations were monitored and cellulose was characterized by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The highest cellulose yield (1.637 g/L) was obtained in SCP50-7d, which molasses of 1/2 ratio for 7 days by static semi-continuous operation mode. The results show that BC can be highly produced by G. xylinus in molasses with static semi-continuous process than batch process. We claimed that low-cost medium with semi-continuous operation mode in static culture is a good candidate for industrial scale BC productions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Omega-3 production by fermentation of Yarrowia lipolytica: From fed-batch to continuous.

    Science.gov (United States)

    Xie, Dongming; Miller, Edward; Sharpe, Pamela; Jackson, Ethel; Zhu, Quinn

    2017-04-01

    The omega-3 fatty acid, cis-5,8,11,14,17-eicosapentaenoic acid (C20:5; EPA) has wide-ranging benefits in improving heart health, immune function, and mental health. A sustainable source of EPA production through fermentation of metabolically engineered Yarrowia lipolytica has been developed. In this paper, key fed-batch fermentation conditions were identified to achieve 25% EPA in the yeast biomass, which is so far the highest EPA titer reported in the literature. Dynamic models of the EPA fermentation process were established for analyzing, optimizing, and scaling up the fermentation process. In addition, model simulations were used to develop a two-stage continuous process and compare to single-stage continuous and fed- batch processes. The two stage continuous process, which is equipped with a smaller growth fermentor (Stage 1) and a larger production fermentor (Stage 2), was found to be a superior process to achieve high titer, rate, and yield of EPA. A two-stage continuous fermentation experiment with Y. lipolytica strain Z7334 was designed using the model simulation and then tested in a 2 L and 5 L fermentation system for 1,008 h. Compared with the standard 2 L fed-batch process, the two-stage continuous fermentation process improved the overall EPA productivity by 80% and EPA concentration in the fermenter by 40% while achieving comparable EPA titer in biomass and similar conversion yield from glucose. During the long-term experiment it was also found that the Y. lipolytica strain evolved to reduce byproduct and increase lipid production. This is one of the few continuous fermentation examples that demonstrated improved productivity and concentration of a final product with similar conversion yield compared with a fed-batch process. This paper suggests the two-stage continuous fermentation could be an effective process to achieve improved production of omega-3 and other fermentation products where non-growth or partially growth associated kinetics

  3. Performances comparison between three technologies for continuous ethanol production from molasses

    International Nuclear Information System (INIS)

    Bouallagui, Hassib; Touhami, Youssef; Hanafi, Nedia; Ghariani, Amine; Hamdi, Moktar

    2013-01-01

    Molasses are a potential feedstock for ethanol production. The successful application of anaerobic fermentation for ethanol production from molasses is critically dependent to the development and the use of high rate bioreactors. In this study the fermentation of sugar cane molasses by Saccharomyces cerevisiae for the ethanol production in a continuously stirred tank reactor (CSTR), an immobilised cell reactor (ICR) and a membrane reactor (MBR) was investigated. Ethanol production and reactor productivities were compared under different dilution rates (D). When using the CSTR, a decent ethanol productivity (Qp) of 6.8 g L −1 h −1 was obtained at a dilution rate of 0.5 h −1 . The Qp was improved by 48% and the residual sugar concentration was reduced by using the ICR. Intensifying the production of ethanol was investigated in the MBR to achieve a maximum ethanol concentration and a Qp of 46.5 g L −1 and 19.2 g L −1 h −1 , respectively. The achieved results in the MBR worked with high substrate concentration are promising for the scale up operation. -- Highlights: ► We compare three reactors for ethanol production from sugar cane molasses. ► The ethanol productivity of 6.8 g L -1 h -1 was obtained using the CSTR. ► The ethanol productivity was improved by 48% by using the ICR. ► Intensifying ethanol productivity (19.2 g L -1 h -1 ) was investigated in the MBR

  4. Bifurcation analysis of a product inhibition model of a continuous fermentation process

    Energy Technology Data Exchange (ETDEWEB)

    Lenbury, Y; Chiaranai, C

    1987-03-01

    A product inhibition model of a continuous fermentation process is considered. If the yield term is a variable function of ethanol concentration, oscillation in the cell and ethanol concentrations is shown to be a Hopf bifurcation in the underlying system of nonlinear, ordinary differential equations which comprises the model.

  5. Continuous operation of a pilot plant for the production of beryllium oxide

    Energy Technology Data Exchange (ETDEWEB)

    Costa, T C; Amaral, S; Silveira, C M.S.; de Oliveira, A P [Instituto de Tecnologia, Governador Valadares (Brazil)

    1975-12-01

    A method of obtaining beryllium oxide with a purity of 99,2% was developed in a pilot plant with a capacity of 7 tons per month destined to operate continuously. The operation market prospects and control of production with the objective of obtaining internacional technical grade beryllium oxide are discussed.

  6. Continuous operation of a pilot plant for the production of beryllium oxide

    International Nuclear Information System (INIS)

    Costa, T.C.; Amaral, S.; Silveira, C.M.S.; Oliveira, A.P. de

    1975-01-01

    A method of obtaining beryllium oxide with a purity of 99,2% was developed in a pilot plant with a capacity of 7 tons per month destined to operate continuously. The operation market prospects and control of production with the objective of obtaining internacional technical grade beryllium oxide are discussed [pt

  7. Continuous butyric acid fermentation coupled with REED technology for enhanced productivity

    DEFF Research Database (Denmark)

    Baroi, George Nabin; Skiadas, Ioannis; Westermann, Peter

    strains, C.tyrobutyricum seems the most promising for biological production of butyric acid as it is characterised by higher selectivity and higher tolerance to butyric acid. However, studies on fermentative butyric production from lignocellulosic biomasses are scarce in the international literature...... of continuous fermentation mode and in-situ acids removal by Reverse Enhanced Electro Dialysis (REED) resulted to enhanced sugars consumption rates when 60% PHWS was fermented. Specifically, glucose and xylose consumption rate increased by a factor of 6 and 39, respectively, while butyric acid productivity...

  8. Continuous production of chitooligosaccharides by an immobilized enzyme in a dual-reactor system

    DEFF Research Database (Denmark)

    Santos-Moriano, Paloma; Woodley, John; Plou, Francisco J.

    2016-01-01

    A chitosanolytic activity found in a commercial α-amylase from Bacillus amylolyquefaciens (BAN) was covalently immobilized onto glyoxal agarose beads (25% recovery of activity) and assessed for the continuous production of chitooligosaccharides (COS). The immobilization did not change the reactio......, the productivity of the PBR at the lowest dilution rate was 37 gCOS L−1 h−1, with a conversion yield of 73%. In contrast, at the highest dilution rate, the productivity was nearly 200 gCOS L−1 h−1, but the conversion yield dropped to around 40%....

  9. Continuous radiochemical analysis of fission products in a nuclear reactor water coolant

    International Nuclear Information System (INIS)

    Moskvin, L.N.; Zakharov, L.K.; Leont'ev, G.G.; Mel'nikov, V.A.; Orlenkov, I.S.; Slutskij, G.K.

    1975-01-01

    Method for continuous radiochemical analysis of I, Cs, Ba, Sr and Ce isotopes in a reactor water heat-transfer agent was developed. A continuous two-dimensional chromatographic process of complex mixtures separation of substances proved to be feasible on several parallel sorbent layers, which moved at constant velocities and separated by stationary intermediate collectors. Tests on model solutions containing I, Ce, Cs and Ba isotopes and on heat-carrier samples showed quantitative separation of elements. The results were indicative of a basic possibility of using multisorbent chromatographs for continuous control of multicomponent mixtures, particularly for control of radioactive fission product compositions in water heat-transfer agents in nuclear power plants. A diagram is shown for a two-dimensional chromatographic separation of a multicomponent mixture. Also shown is a flow chart of an installation for continuous control of iodine and cesium isotope activities

  10. Continuous esterification for biodiesel production from palm fatty acid distillate using economical process

    Energy Technology Data Exchange (ETDEWEB)

    Chongkhong, S.; Tongurai, C.; Chetpattananondh, P. [Department of Chemical Engineering, Faculty of Engineering, Prince of Songkla University, Hat-Yai, Songkhla 90112 (Thailand)

    2009-04-15

    An overflow system for continuous esterification of palm fatty acid distillate (PFAD) using an economical process was developed using a continuous stirred tank reactor (CSTR). Continuous production compared to batch production at the same condition had higher product purity. The optimum condition for the esterification process was a 8.8:1:0.05 molar ratio of methanol to PFAD to sulfuric acid catalyst, 60 min of residence time at 75 C under its own pressure. The free fatty acid (FFA) content in the PFAD was reduced from 93 to less than 1.5%wt by optimum esterification. The esterified product had to be neutralized with 10.24%wt of 3 M sodium hydroxide in water solution at a reaction temperature of 80 C for 20 min to reduce the residual FFA and glycerides. The components and properties of fatty acid methyl ester (FAME) could meet the standard requirements for biodiesel fuel. Eventually the production costs were calculated to disclose its commercialization. (author)

  11. Continuous-Time Classical and Quantum Random Walk on Direct Product of Cayley Graphs

    International Nuclear Information System (INIS)

    Salimi, S.; Jafarizadeh, M. A.

    2009-01-01

    In this paper we define direct product of graphs and give a recipe for obtaining probability of observing particle on vertices in the continuous-time classical and quantum random walk. In the recipe, the probability of observing particle on direct product of graph is obtained by multiplication of probability on the corresponding to sub-graphs, where this method is useful to determining probability of walk on complicated graphs. Using this method, we calculate the probability of continuous-time classical and quantum random walks on many of finite direct product Cayley graphs (complete cycle, complete K n , charter and n-cube). Also, we inquire that the classical state the stationary uniform distribution is reached as t → ∞ but for quantum state is not always satisfied. (general)

  12. Continuous Production of IF-WS2 Nanoparticles by a Rotary Process

    Directory of Open Access Journals (Sweden)

    Fang Xu

    2014-06-01

    Full Text Available This manuscript demonstrates the design, modification and initial investigation of a rotary furnace for the manufacturing of inorganic fullerene WS2 nanoparticles. Different preparation methods starting with various precursors have been investigated, of which the gas-solid reaction starting with WO3 nanoparticles was the most efficient technique. Furthermore, the influence of temperature, reaction time, and reaction gases etc. on the synthesis of inorganic fullerene WS2 nanomaterials was investigated, and these parameters were optimised based on combined characterisations using XRD, SEM and TEM. In addition, the furnace was further modified to include a baffled tube, a continuous gas-blow feeding system, and a collection system, in order to improve the batch yield and realise continuous production. This technique has improved the production from less than 1 g/batch in a traditional tube furnace to a few tens of g/batch, and could be easily scaled up to industry level production.

  13. Development of a novel integrated continuous reactor system for biocatalytic production of biodiesel.

    Science.gov (United States)

    Chattopadhyay, Soham; Sen, Ramkrishna

    2013-11-01

    A novel integrated immobilized enzyme-reactor system involving a continuous stirred tank reactor with two packed bed reactors in series was developed for the continuous production of biodiesel. The problem of methanol solubility into oil was solved by introducing a stirred tank reactor to dissolve methanol into partially converted oil. This step made the process perfectly continuous without requiring any organic solvent and intermittent methanol addition in the process. The substrate feeding rate of 0.74 mL/min and enzyme loading of 0.75 g per reactor were determined to be optimum for maximum biodiesel yield. The integrated continuous process was stable up to 45 cycles with biodiesel productivity of 137.2 g/L/h, which was approximately 5 times higher than solvent free batch process. In comparison with the processes reported in literature using expensive Novozyme 435 and hazardous organic solvent, the present process is completely green and perfectly continuous with economic and environmental advantages. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Biological hydrogen production in continuous stirred tank reactor systems with suspended and attached microbial growth

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Nan-Qi; Tang, Jing; Liu, Bing-Feng; Guo, Wan-Qian [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, No.202 Haihe Road, Harbin 150090 (China)

    2010-04-15

    Fermentative H{sub 2} production in continuous stirred tank reactor (CSTR) system with bacteria attached onto granular activated carbon (GAC) was designed to produce H{sub 2} continuously. The H{sub 2} production performances of CSTR with suspended and attached-sludge from molasses were examined and compared at various organic loading rates (8-40 g COD/L/d) at hydraulic retention time of 6 h under mesophilic conditions (35 C). Both reactor systems achieved ethanol-type fermentation in the pH ranges 4.5-4.8 and 3.8-4.4, respectively, while ORP ranges from -450 to -470 mV and from -330 to -350 mV, respectively. The hydrogen production rate in the attached system was higher compared to that of the suspended system (9.72 and 6.65 L/d/L, respectively) while specific hydrogen production rate of 5.13 L/g VSS/d was higher in the suspended system. The attached-sludge CSTR is more stable than the suspended-sludge CSTR with regard to hydrogen production, pH, substrate utilization efficiency and metabolic products (e.g., volatile fatty acids and ethanol) during the whole test. (author)

  15. Continuous production of pectinase by immobilized yeast cells on spent grains.

    Science.gov (United States)

    Almeida, Catarina; Brányik, Tomás; Moradas-Ferreira, Pedro; Teixeira, José

    2003-01-01

    A yeast strain secreting endopolygalacturonase was used in this work to study the possibility of continuous production of this enzyme. It is a feasible and interesting alternative to fungal batch production essentially due to the specificity of the type of pectinase excreted by Kluyveromyces marxianus CCT 3172, to the lower broth viscosity and to the easier downstream operations. In order to increase the reactors' productivity, a cellulosic carrier obtained from barley spent grains was tested as an immobilization support. Two types of reactors were studied for pectinase production using glucose as a carbon and energy source--a continuous stirred tank reactor (CSTR) and a packed bed reactor (PBR) with recycled flow. The highest value for pectinase volumetric productivity (P(V)=0.98 U ml(-1) h(-1)) was achieved in the PBR for D=0.40 h(-1), a glucose concentration on the inlet of S(in)=20 g l(-1), and a biomass load in the support of X(i)=0.225 g g(-1). The results demonstrate the attractiveness of the packed bed system for pectinase production.

  16. PDCA cycle as a part of continuous improvement in the production company - a case study

    Directory of Open Access Journals (Sweden)

    Marta Jagusiak-Kocik

    2017-04-01

    Full Text Available The paper presents a case study of the practical use of Deming cycle in a manufacturing company, from the plastics processing industry, from the sector of small and medium-sized enterprises. The paper is a study of literature in the field of continuous improvement and characterized by a cycle of continuous improvement, called the Deming cycle, or PDCA cycle. This cycle was used as a solution to quality problems which occurred during production of photo frames: discolorations and scorches on the surface of the frame. When measures were introduced to reduce the number of nonconformities, a decrease by more than 60% was observed.

  17. Technological aspects at continuous casting of semi-finished products with ϕ270mm

    International Nuclear Information System (INIS)

    Ardelean, E; Ardelean, M; Hepuţ, T; Lăscuţoni, A

    2015-01-01

    Continuous casting installation especially appreciated because steel can be poured in a more varied assortment. The flexibility of the system is not sufficient if the casting parameters are not properly adopted and adapted to the specific brand of steel. This paper presents some technical aspects relative to continuous casting of semi-finished products with ϕ270mm section. Graphical dependencies obtained in Excel and analytical equations of this allows to specialists from industry to adopt values for the addicted parameters according to the independent ones, already known. (paper)

  18. Bioaggregate of photo-fermentative bacteria for enhancing continuous hydrogen production in a sequencing batch photobioreactor.

    Science.gov (United States)

    Xie, Guo-Jun; Liu, Bing-Feng; Wang, Rui-Qing; Ding, Jie; Ren, Hong-Yu; Zhou, Xu; Ren, Nan-Qi

    2015-11-05

    Hydrogen recovery through solar-driven biomass conversion by photo-fermentative bacteria (PFB) has been regarded as a promising way for sustainable energy production. However, a considerable fraction of organic substrate was consumed for the growth of PFB as biocatalysts, furthermore, these PFB were continuously washed out from the photobioreactor in continuous operation because of their poor flocculation. In this work, PFB bioaggregate induced by L-cysteine was applied in a sequencing batch photobioreactor to enhance continuous hydrogen production and reduce biomass washout. The effects of the hydraulic retention time (HRT), influent concentration and light intensity on hydrogen production of the photobioreactor were investigated. The maximum hydrogen yield (3.35 mol H2/mol acetate) and production rate (1044 ml/l/d) were obtained at the HRT of 96 h, influent concentration of 3.84 g COD/l, and light intensity of 200 W/m(2). With excellent settling ability, biomass accumulated in the photobioreactor and reached 2.15 g/l under the optimum conditions. Structural analysis of bioaggregate showed that bacterial cells were covered and tightly linked together by extracellular polymeric substances, and formed a stable structure. Therefore, PFB bioaggregate induced by L-cysteine is an efficient strategy to improve biomass retention capacity of the photobioreactor and enhance hydrogen recovery efficiency from organic wastes.

  19. Bioaggregate of photo-fermentative bacteria for enhancing continuous hydrogen production in a sequencing batch photobioreactor

    Science.gov (United States)

    Xie, Guo-Jun; Liu, Bing-Feng; Wang, Rui-Qing; Ding, Jie; Ren, Hong-Yu; Zhou, Xu; Ren, Nan-Qi

    2015-11-01

    Hydrogen recovery through solar-driven biomass conversion by photo-fermentative bacteria (PFB) has been regarded as a promising way for sustainable energy production. However, a considerable fraction of organic substrate was consumed for the growth of PFB as biocatalysts, furthermore, these PFB were continuously washed out from the photobioreactor in continuous operation because of their poor flocculation. In this work, PFB bioaggregate induced by L-cysteine was applied in a sequencing batch photobioreactor to enhance continuous hydrogen production and reduce biomass washout. The effects of the hydraulic retention time (HRT), influent concentration and light intensity on hydrogen production of the photobioreactor were investigated. The maximum hydrogen yield (3.35 mol H2/mol acetate) and production rate (1044 ml/l/d) were obtained at the HRT of 96 h, influent concentration of 3.84 g COD/l, and light intensity of 200 W/m2. With excellent settling ability, biomass accumulated in the photobioreactor and reached 2.15 g/l under the optimum conditions. Structural analysis of bioaggregate showed that bacterial cells were covered and tightly linked together by extracellular polymeric substances, and formed a stable structure. Therefore, PFB bioaggregate induced by L-cysteine is an efficient strategy to improve biomass retention capacity of the photobioreactor and enhance hydrogen recovery efficiency from organic wastes.

  20. Fiscal 1997 survey report on a feasibility of international collaboration on bio-hydrogen R and D; 1997 nendo chosa hokokusho (bio suiso seizo gijutsu ni kakawaru kokusai kyoryoku kanosei chosa)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    R and D of the production technology of biohydrogen is an option effective for the world energy supply technology and the world environmental preservation technology in the 21st century. At present, a project named `R and D of the environment harmony type hydrogen production technology` tackles the R and D of the hydrogen production technology using photosynthetic microorganisms, and promotes the R and D in this field from both aspects of a basis and application as seen in a workshop held including interchanges with researchers and research institutes overseas. With the recently increasing interest in bio-hydrogen production technology also overseas, search and bleeding/improvement of microorganisms related to the hydrogen production and utilization technology of biomass have been advancing. For development in this field, it is necessary to construct a widespread research network and promote the comprehensive research and development. In this survey, most of the research institutes visited recognized an importance of international cooperation in this field and agreed to make future research interchanges in a wide range. Based on the survey, a feasibility of concrete international collaboration is searched. 146 refs., 2 figs., 11 tabs.

  1. Development of High-Productivity Continuous Ethanol Production using PVA-Immobilized Zymomonas mobilis in an Immobilized-Cells Fermenter

    Directory of Open Access Journals (Sweden)

    Nurhayati Nurhayati

    2015-07-01

    Full Text Available Ethanol as one of renewable energy was being considered an excellent alternative clean-burning fuel to replace gasoline. Continuous ethanol fermentation systems had offered important economic advantages compared to traditional systems. Fermentation rates were significantly improved, especially when continuous fermentation was integrated with cell immobilization techniques to enrich the cells concentration in fermentor. Growing cells of Zymomonas mobilis immobilized in polyvinyl alcohol (PVA gel beads were employed in an immobilized-cells fermentor for continuous ethanol fermentation from glucose. The glucose loading, dilution rate, and cells loading were varied in order to determine which best condition employed in obtaining both high ethanol production and low residual glucose with high dilution rate. In this study, 20 g/L, 100 g/L, 125 g/L and 150 g/L of glucose concentration and 20% (w/v, 40% (w/v and 50% (w/v of cells loading were employed with range of dilution rate at 0.25 to 1 h-1. The most stable production was obtained for 25 days by employing 100 g/L of glucose loading. Meanwhile, the results also exhibited that 125 g/L of glucose loading as well as 40% (w/v of cells loading yielded high ethanol concentration, high ethanol productivity, and acceptable residual glucose at 62.97 g/L, 15.74 g/L/h and 0.16 g/L, respectively. Furthermore, the dilution rate of 4 hour with 100 g/L and 40% (w/v of glucose and cells loading was considered as the optimum condition with ethanol production, ethanol productivity and residual glucose obtained were 49.89 g/L, 12.47 g/L/h, and 2.04 g/L, respectively. This recent study investigated ethanol inhibition as well. The present research had proved that high sugar concentration was successfully converted to ethanol. These achieved results were promising for further study.

  2. DEVELOPMENT OF CONTINUOUS SOLVENT EXTRACTION PROCESSES FOR COAL DERIVED CARBON PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    Dady B. Dadyburjor; Mark E. Heavner; Manoj Katakdaunde; Liviu Magean; J. Joshua Maybury; Alfred H. Stiller; Joseph M. Stoffa; John W. Zondlo

    2006-08-01

    The purpose of this DOE-funded effort is to develop continuous processes for solvent extraction of coal for the production of carbon products. The largest applications are those which support metals smelting, such as anodes for aluminum smelting and electrodes for arc furnaces. Other carbon products include materials used in creating fuels for the Direct Carbon Fuel Cell, and porous carbon structural material referred to as ''carbon foam'' and carbon fibers. During this reporting period, hydrotreatment of solvent was completed in preparation for pitch fabrication for graphite electrodes. Coal digestion has lagged but is expected to be complete by next quarter. Studies are reported on coal dissolution, pitch production, foam synthesis using physical blowing agents, and alternate coking techniques.

  3. Continuous fission-product monitor system at Oyster Creek. Final report

    International Nuclear Information System (INIS)

    Collins, L.L.; Chulick, E.T.

    1980-10-01

    A continuous on-line fission product monitor has been installed at the Oyster Creek Nuclear Generating Station, Forked River, New Jersey. The on-line monitor is a minicomputer-controlled high-resolution gamma-ray spectrometer system. An intrinsic Ge detector scans a collimated sample line of coolant from one of the plant's recirculation loops. The minicomputer is a Nuclear Data 6620 system. Data were accumulated for the period from April 1979 through January 1980, the end of cycle 8 for the Oyster Creek plant. Accumulated spectra, an average of three a day, were stored on magnetic disk and subsequently analyzed for fisson products, Because of difficulties in measuring absolute detector efficiency, quantitative fission product concentrations in the coolant could not be determined. Data for iodine fission products are reported as a function of time. The data indicate the existence of fuel defects in the Oyster Creek core during cycle 8

  4. DEVELOPMENT OF CONTINUOUS SOLVENT EXTRACTION PROCESSES FOR COAL DERIVED CARBON PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    Elliot B. Kennel; Quentin C. Berg; Stephen P. Carpenter; Dady Dadyburjor; Jason C. Hissam; Manoj Katakdaunde; Liviu Magean; Abha Saddawi; Alfred H. Stiller; John W. Zondlo

    2006-03-07

    The purpose of this DOE-funded effort is to develop continuous processes for solvent extraction of coal for the production of carbon products. The largest applications are those which support metals smelting, such as anodes for aluminum smelting and electrodes for arc furnaces. Other carbon products include materials used in creating fuels for the Direct Carbon Fuel Cell, metals smelting, especially in the aluminum and steel industries, as well as porous carbon structural material referred to as ''carbon foam'' and carbon fibers. During this reporting period, efforts have focused on the development of carbon electrodes for Direct Carbon Fuel Cells (DCFC), and on carbon foam composites used in ballistic armor, as well as the hydrotreatment of solvents used in the basic solvent extraction process. A major goal is the production of 1500 pounds of binder pitch, corresponding to about 3000 pounds of hydrotreated solvent.

  5. 40 CFR 63.6004 - How do I demonstrate continuous compliance with the emission limits for tire production affected...

    Science.gov (United States)

    2010-07-01

    ... compliance with the emission limits for tire production affected sources? 63.6004 Section 63.6004 Protection... Pollutants: Rubber Tire Manufacturing Continuous Compliance Requirements for Tire Production Affected Sources § 63.6004 How do I demonstrate continuous compliance with the emission limits for tire production...

  6. Continuous dark fermentative hydrogen production by mesophilic microflora: Principles and progress

    Energy Technology Data Exchange (ETDEWEB)

    Hawkes, Freda R.; Hussy, Ines; Kyazze, Godfrey; Dinsdale, Richard; Hawkes, Dennis L. [School of Applied Sciences, University of Glamorgan, Pontypridd RCT CF37 1DL (United Kingdom)

    2007-02-15

    Continuous, dark fermentative hydrogen production technology using mixed microflora at mesophilic temperatures may be suitable for commercial development. Clostridial-based cultures from natural sources have been widely used, but more information on the need for heat treatment of inocula and conditions leading to germination and sporulation are required. The amount of nutrients given in the literature vary widely. Hydrogen production is reported to proceed without methane production in the reactor in the pH range 4.5-6.7, with hydraulic retention times optimally between a few hours and 3 days depending on substrate. Higher substrate concentrations should be more energy-efficient but there are product inhibition limitations, for example from unionised butyric acid. Inhibition by H{sub 2} can be reduced by stirring, sparging or extraction through membranes. Of the reactor types investigated, while granules have the best performance with soluble substrate, for particulate feedstock biofilm reactors or continuous stirred tank reactors may be most successful. A second stage is required to utilise the fermentation end products which, when cost-effective reactors are developed, may be photofermentation or microbial fuel cell technologies. Anaerobic digestion is a currently-available technology and the two-stage process is reported to give greater conversion efficiency than anaerobic digestion alone. (author)

  7. Bio-immobilization of dark fermentative bacteria for enhancing continuous hydrogen production from cornstalk hydrolysate.

    Science.gov (United States)

    Zhao, Lei; Cao, Guang-Li; Sheng, Tao; Ren, Hong-Yu; Wang, Ai-Jie; Zhang, Jian; Zhong, Ying-Juan; Ren, Nan-Qi

    2017-11-01

    Mycelia pellets were employed as biological carrier in a continuous stirred tank reactor to reduce biomass washout and enhance hydrogen production from cornstalk hydrolysate. Hydraulic retention time (HRT) and influent substrate concentration played critical roles on hydrogen production of the bioreactor. The maximum hydrogen production rate of 14.2mmol H 2 L -1 h -1 was obtained at optimized HRT of 6h and influent concentration of 20g/L, 2.6 times higher than the counterpart without mycelia pellets. With excellent immobilization ability, biomass accumulated in the reactor and reached 1.6g/L under the optimum conditions. Upon further energy conversion analysis, continuous hydrogen production with mycelia pellets gave the maximum energy conversion efficiency of 17.8%. These results indicate mycelia pellet is an ideal biological carrier to improve biomass retention capacity of the reactor and enhance hydrogen recovery efficiency from lignocellulosic biomass, and meanwhile provides a new direction for economic and efficient hydrogen production process. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Development of an advanced continuous mild gasification process for the production of coproducts

    Energy Technology Data Exchange (ETDEWEB)

    Merriam, N.W.; Jha, M.C.

    1991-11-01

    This report is a final brief summary of development of a mild-gasification and char conversion process. Morgantown Energy Technology Center developed a concept called mild gasification. In this concept, devolatilization of coal under nonoxidizing and relatively mild temperature and pressure conditions can yield three marketable products: (1) a high-heating-value gas, (2) a high-aromatic coal liquid, and (3) a high-carbon char. The objective of this program is to develop an advanced, continuous, mild-gasification process to produce products that will make the concept economically and environmentally viable. (VC)

  9. Development of an advanced continuous mild gasification process for the production of coproducts. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Merriam, N.W.; Jha, M.C.

    1991-11-01

    This report is a final brief summary of development of a mild-gasification and char conversion process. Morgantown Energy Technology Center developed a concept called mild gasification. In this concept, devolatilization of coal under nonoxidizing and relatively mild temperature and pressure conditions can yield three marketable products: (1) a high-heating-value gas, (2) a high-aromatic coal liquid, and (3) a high-carbon char. The objective of this program is to develop an advanced, continuous, mild-gasification process to produce products that will make the concept economically and environmentally viable. (VC)

  10. MANAGEMENT OF INVENTORIES IN AN ENTEPRISE IN THE CONTEXT OF PRODUCTION CONTINUITY

    Directory of Open Access Journals (Sweden)

    Izabela EMERLING

    2014-04-01

    Full Text Available Inventories are a very important category in the accounting of every enterprise. Inventory management is one of the major decision‐making areas for the company’s management board. Proper inventory management allows reducing total costs and increasing the quality of production, which is the goal of an integrated management system. Proper financial management can also positively affect the maintenance of liquidity in the company. The purpose of this article is to present issues related to inventory management in a company in the context of continuity of production and fluidity of a subject.

  11. A systematic methodology for the design of continuous active pharmaceutical ingredient production processes

    DEFF Research Database (Denmark)

    Cervera Padrell, Albert Emili; Gani, Rafiqul; Kiil, Søren

    2011-01-01

    Continuous pharmaceutical manufacturing (CPM) has emerged as a powerful technology to obtain higher reaction yields and improved separation efficiencies, potentially leading to simplified process flowsheets, reduced total costs, lower environmental impacts, and safer and more flexible production...... and representation, as well as on how to employ this knowledge for process (re-)design. The aim of this paper is to introduce a methodology that systematically identifies already existing PSE methods and tools which can assist in the design of CPM processes. This methodology has been applied to a process...... for the production of an API developed by H. Lundbeck A/S, demonstrating the mentioned potential benefits that CPM can offer....

  12. Facility design consideration for continuous mix production of class 1.3 propellant

    Science.gov (United States)

    Williamson, K. L.; Schirk, P. G.

    1994-01-01

    In November of 1989, NASA awarded the Advanced Solid Rocket Motor (ASRM) contract to Lockheed Missiles and Space Company (LMSC) for production of advanced solid rocket motors using the continuous mix process. Aerojet ASRM division (AAD) was selected as the facility operator and RUST International Corporation provided the engineering, procurement, and construction management services. The continuous mix process mandates that the mix and cast facilities be 'close-coupled' along with the premix facilities, creating unique and challenging requirements for the facility designer. The classical approach to handling energetic materials-division into manageable quantities, segregation, and isolation-was not available due to these process requirements and quantities involved. This paper provides a description of the physical facilities, the continuous mix process, and discusses the monitoring and detection techniques used to mitigate hazards and prevent an incident.

  13. Continuous production of ethanol from hexoses and pentoses using immobilized mixed cultures of Escherichia coli strains

    Science.gov (United States)

    Unrean, Pornkamol; Srienc, Friedrich

    2010-01-01

    We have developed highly efficient ethanologenic E. coli strains that selectively consume pentoses and/or hexoses. Mixed cultures of these strains can be used to selectively adjust the sugar utilization kinetics in ethanol fermentations. Based on the kinetics of sugar utilization, we have designed and implemented an immobilized cell system for the optimized continuous conversion of sugars into ethanol. The results confirm that immobilized mixed cultures support a simultaneous conversion of hexoses and pentoses into ethanol at high yield and at a faster rate than immobilized homogenous cells. Continuous ethanol production has been maintained for several weeks at high productivity with near complete sugar utilization. The control of sugar utilization using immobilized mixed cultures can be adapted to any composition of hexoses and pentoses by adjusting the strain distribution of immobilized cells. The approach, therefore, holds promise for ethanol fermentation from lignocellulosic hydrolysates where the feedstock varies in sugar composition. PMID:20699108

  14. Deriving temporally continuous soil moisture estimations at fine resolution by downscaling remotely sensed product

    Science.gov (United States)

    Jin, Yan; Ge, Yong; Wang, Jianghao; Heuvelink, Gerard B. M.

    2018-06-01

    Land surface soil moisture (SSM) has important roles in the energy balance of the land surface and in the water cycle. Downscaling of coarse-resolution SSM remote sensing products is an efficient way for producing fine-resolution data. However, the downscaling methods used most widely require full-coverage visible/infrared satellite data as ancillary information. These methods are restricted to cloud-free days, making them unsuitable for continuous monitoring. The purpose of this study is to overcome this limitation to obtain temporally continuous fine-resolution SSM estimations. The local spatial heterogeneities of SSM and multiscale ancillary variables were considered in the downscaling process both to solve the problem of the strong variability of SSM and to benefit from the fusion of ancillary information. The generation of continuous downscaled remote sensing data was achieved via two principal steps. For cloud-free days, a stepwise hybrid geostatistical downscaling approach, based on geographically weighted area-to-area regression kriging (GWATARK), was employed by combining multiscale ancillary variables with passive microwave remote sensing data. Then, the GWATARK-estimated SSM and China Soil Moisture Dataset from Microwave Data Assimilation SSM data were combined to estimate fine-resolution data for cloudy days. The developed methodology was validated by application to the 25-km resolution daily AMSR-E SSM product to produce continuous SSM estimations at 1-km resolution over the Tibetan Plateau. In comparison with ground-based observations, the downscaled estimations showed correlation (R ≥ 0.7) for both ascending and descending overpasses. The analysis indicated the high potential of the proposed approach for producing a temporally continuous SSM product at fine spatial resolution.

  15. Continuous process of powder production for MOX fuel fabrication according to ''granat'' technology

    International Nuclear Information System (INIS)

    Morkovnikov, V.E.; Raginskiy, L.S.; Pavlinov, A.P.; Chernov, V.A.; Revyakin, V.V.; Varykhanov, V.S.; Revnov, V.N.

    2000-01-01

    During last years the problem of commercial MOX fuel fabrication for nuclear reactors in Russia was solved in a number of directions. The paper deals with the solution of the problem of creating a continuous pilot plant for the production of MOX fuel powders on the basis of the home technology 'Granat', that was tested before on a small-scale pilot-commercial batch-operated plant of the same name and confirmed good results. (authors)

  16. Secondary products and consumption of sugar during continuous alcoholic fermentation of starchy media

    Energy Technology Data Exchange (ETDEWEB)

    Nakhmanovich, B M; Yarovenko, V L; Makeev, D M; Belov, E M

    1976-01-01

    Continuous alcohol fermentation in different media containing starch as the carbon source and final analysis of products indicated that 93.3% glucose is converted into ethanol and CO/sub 2/, 2.78% metabolized by the yeast cells, 2.4% converted into glycerol, 0.036% into acetic acid, 0.25% into lactic acid, and a nonsignificant percentage was changed into other organic acids and higher alcohols.

  17. The business impact of an integrated continuous biomanufacturing platform for recombinant protein production.

    Science.gov (United States)

    Walther, Jason; Godawat, Rahul; Hwang, Chris; Abe, Yuki; Sinclair, Andrew; Konstantinov, Konstantin

    2015-11-10

    The biotechnology industry primarily uses batch technologies to manufacture recombinant proteins. The natural evolution of other industries has shown that transitioning from batch to continuous processing can yield significant benefits. A quantitative understanding of these benefits is critical to guide the implementation of continuous processing. In this manuscript, we use process economic modeling and Monte Carlo simulations to evaluate an integrated continuous biomanufacturing (ICB) platform and conduct risk-based valuation to generate a probabilistic range of net-present values (NPVs). For a specific ten-year product portfolio, the ICB platform reduces average cost by 55% compared to conventional batch processing, considering both capital and operating expenses. The model predicts that these savings can further increase by an additional 25% in situations with higher-than-expected product demand showing the upward potential of the ICB platform. The ICB platform achieves these savings and corresponding flexibility mainly due to process intensification in both upstream and downstream unit operations. This study demonstrates the promise of continuous bioprocessing while also establishing a novel framework to quantify financial benefits of other platform process technologies. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Continuous ethanol production from sugar beet molasses using an osmotolerant mutant strain of zymomonas mobilis

    Energy Technology Data Exchange (ETDEWEB)

    Park, S.C.; Baratti, J.C. (Univ. de Provence, Marseille (France). Centre National de la Recherche Scientifique)

    1992-01-25

    In conventional alcohol fermentation processes using yeast species, the substrate cost represents a major fraction of the total production cost. Therefore, it may be very attractive to use the bacterium Zymomonas mobilis, since it has shown higher ethanol yields than yeasts when grown on a glucose-based medium. A report is made on the use of mutant strain of Zymomonas mobilis for ethanol production from hydrolyzed sugar beet molasses in a two-stage continuous culture which showed high ethanol yield and an ethanol concentration sufficiently high for economical recovery. A single stage continuous culture was first operated in an attempt to reduce the formation of sorbitol. Further on, a second fermentor was added with additional substrate feeding to increase the effluent ethanol concentration. An ethanol concentration of 59.9g/l was obtained at 97% sugar conversion and at high ethanol yield. The volumetric ethanol productivity was superior to that of batch fermentation but inferior to that of a single-stage continuous system with the same medium. However, the ethanol concentration was increased to a level acceptable for economical recovery. 18 refs., 3 figs., 5 tabs.

  19. Process design and optimization of novel wheat-based continuous bioethanol production system.

    Science.gov (United States)

    Arifeen, Najmul; Wang, Ruohang; Kookos, Ioannis K; Webb, Colin; Koutinas, Apostolis A

    2007-01-01

    A novel design of a wheat-based biorefinery for bioethanol production, including wheat milling, gluten extraction as byproduct, fungal submerged fermentation for enzyme production, starch hydrolysis, fungal biomass autolysis for nutrient regeneration, yeast fermentation with recycling integrated with a pervaporation membrane for ethanol concentration, and fuel-grade ethanol purification by pressure swing distillation (PSD), was optimized in continuous mode using the equation-based software General Algebraic Modelling System (GAMS). The novel wheat biorefining strategy could result in a production cost within the range of dollars 0.96-0.50 gal(-1) ethanol (dollars 0.25-0.13 L(-1) ethanol) when the production capacity of the plant is within the range of 10-33.5 million gal y(-1) (37.85-126.8 million L y(-1)). The production of value-added byproducts (e.g., bran-rich pearlings, gluten, pure yeast cells) was identified as a crucial factor for improving the economics of fuel ethanol production from wheat. Integration of yeast fermentation with pervaporation membrane could result in the concentration of ethanol in the fermentation outlet stream (up to 40 mol %). The application of a PSD system that consisted of a low-pressure and a high-pressure column and employing heat integration between the high- and low-pressure columns resulted in reduced operating cost (up to 44%) for fuel-grade ethanol production.

  20. Continuous co-production of ethanol and xylitol from rice straw hydrolysate in a membrane bioreactor.

    Science.gov (United States)

    Zahed, Omid; Jouzani, Gholamreza Salehi; Abbasalizadeh, Saeed; Khodaiyan, Faramarz; Tabatabaei, Meisam

    2016-05-01

    The present study was set to develop a robust and economic biorefinery process for continuous co-production of ethanol and xylitol from rice straw in a membrane bioreactor. Acid pretreatment, enzymatic hydrolysis, detoxification, yeast strains selection, single and co-culture batch fermentation, and finally continuous co-fermentation were optimized. The combination of diluted acid pretreatment (3.5 %) and enzymatic conversion (1:10 enzyme (63 floating-point unit (FPU)/mL)/biomass ratio) resulted in the maximum sugar yield (81 % conversion). By concentrating the hydrolysates, sugars level increased by threefold while that of furfural reduced by 50 % (0.56 to 0.28 g/L). Combined application of active carbon and resin led to complete removal of furfural, hydroxyl methyl furfural, and acetic acid. The strains Saccharomyces cerevisiae NCIM 3090 with 66.4 g/L ethanol production and Candida tropicalis NCIM 3119 with 9.9 g/L xylitol production were selected. The maximum concentrations of ethanol and xylitol in the single cultures were recorded at 31.5 g/L (0.42 g/g yield) and 26.5 g/L (0.58 g/g yield), respectively. In the batch co-culture system, the ethanol and xylitol productions were 33.4 g/L (0.44 g/g yield) and 25.1 g/L (0.55 g/g yield), respectively. The maximum ethanol and xylitol volumetric productivity values in the batch co-culture system were 65 and 58 % after 25 and 60 h, but were improved in the continuous co-culture mode and reached 80 % (55 g/L) and 68 % (31 g/L) at the dilution rate of 0.03 L per hour, respectively. Hence, the continuous co-production strategy developed in this study could be recommended for producing value-added products from this hugely generated lignocellulosic waste.

  1. Continuous ethanol production using immobilized yeast cells entrapped in loofa-reinforced alginate carriers

    Directory of Open Access Journals (Sweden)

    Phoowit Bangrak

    2011-06-01

    Full Text Available A culture of Saccharomyces cerevisiae M30 entrapped in loofa-reinforced alginate was used for continuous ethanol fermentation in a packed-bed reactor with initial sugar concentrations of 200-248 g/L. Maximum ethanol productivity of 11.5 g/(L·h was obtained at an ethanol concentration of 57.4 g/L, an initial sugar concentration of 220 g/L and a dilution rate (D of 0.2 h-1. However, a maximum ethanol concentration of 82.1 g/L (productivity of 9.0 g/(L·h was obtained at a D of 0.11 h-1. Ethanol productivity in the continuous culture was 6-8-fold higher than that in the batch culture. Due to the developed carrier's high biocompatibility, high porosity, and good mechanical strength, advantages such as cell regeneration, reusability, altered mechanical strength, and high capacity to trap active cells in the reactor were achieved in this study. The immobilized cell reactor was successfully operated for 30 days without any loss in ethanol productivity. The average conversion yield was 0.43-0.45 throughout the entire operation, with an immobilization yield of 47.5%. The final total cell concentration in the reactor was 37.3 g/L (17.7 g/L immobilized cells and 19.6 g/L suspended cells. The concentration of suspended cells in the effluent was 0.8 g/L.

  2. Planning Risk-Based SQC Schedules for Bracketed Operation of Continuous Production Analyzers.

    Science.gov (United States)

    Westgard, James O; Bayat, Hassan; Westgard, Sten A

    2018-02-01

    To minimize patient risk, "bracketed" statistical quality control (SQC) is recommended in the new CLSI guidelines for SQC (C24-Ed4). Bracketed SQC requires that a QC event both precedes and follows (brackets) a group of patient samples. In optimizing a QC schedule, the frequency of QC or run size becomes an important planning consideration to maintain quality and also facilitate responsive reporting of results from continuous operation of high production analytic systems. Different plans for optimizing a bracketed SQC schedule were investigated on the basis of Parvin's model for patient risk and CLSI C24-Ed4's recommendations for establishing QC schedules. A Sigma-metric run size nomogram was used to evaluate different QC schedules for processes of different sigma performance. For high Sigma performance, an effective SQC approach is to employ a multistage QC procedure utilizing a "startup" design at the beginning of production and a "monitor" design periodically throughout production. Example QC schedules are illustrated for applications with measurement procedures having 6-σ, 5-σ, and 4-σ performance. Continuous production analyzers that demonstrate high σ performance can be effectively controlled with multistage SQC designs that employ a startup QC event followed by periodic monitoring or bracketing QC events. Such designs can be optimized to minimize the risk of harm to patients. © 2017 American Association for Clinical Chemistry.

  3. Odds Ratio Product of Sleep EEG as a Continuous Measure of Sleep State

    Science.gov (United States)

    Younes, Magdy; Ostrowski, Michele; Soiferman, Marc; Younes, Henry; Younes, Mark; Raneri, Jill; Hanly, Patrick

    2015-01-01

    Study Objectives: To develop and validate an algorithm that provides a continuous estimate of sleep depth from the electroencephalogram (EEG). Design: Retrospective analysis of polysomnograms. Setting: Research laboratory. Participants: 114 patients who underwent clinical polysomnography in sleep centers at the University of Manitoba (n = 58) and the University of Calgary (n = 56). Interventions: None. Measurements and Results: Power spectrum of EEG was determined in 3-second epochs and divided into delta, theta, alpha-sigma, and beta frequency bands. The range of powers in each band was divided into 10 aliquots. EEG patterns were assigned a 4-digit number that reflects the relative power in the 4 frequency ranges (10,000 possible patterns). Probability of each pattern occurring in 30-s epochs staged awake was determined, resulting in a continuous probability value from 0% to 100%. This was divided by 40 (% of epochs staged awake) producing the odds ratio product (ORP), with a range of 0–2.5. In validation testing, average ORP decreased progressively as EEG progressed from wakefulness (2.19 ± 0.29) to stage N3 (0.13 ± 0.05). ORP sleep and ORP > 2.0 predicted wakefulness in > 95% of 30-s epochs. Epochs with intermediate ORP occurred in unstable sleep with a high arousal index (> 70/h) and were subject to much interrater scoring variability. There was an excellent correlation (r2 = 0.98) between ORP in current 30-s epochs and the likelihood of arousal or awakening occurring in the next 30-s epoch. Conclusions: Our results support the use of the odds ratio product (ORP) as a continuous measure of sleep depth. Citation: Younes M, Ostrowski M, Soiferman M, Younes H, Younes M, Raneri J, Hanly P. Odds ratio product of sleep EEG as a continuous measure of sleep state. SLEEP 2015;38(4):641–654. PMID:25348125

  4. Mathematical modelling and optimization of hydrogen continuous production in a fixed bed bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Palazzi, E.; Perego, P.; Fabiano, B. [University of Genoa, Genova (Italy). Chemical and Process Engineering Department ' G.B. Bonino'

    2002-09-01

    The purpose of this paper is to investigate, both theoretically and experimentally, hydrogen production from agro-industrial by-products using a continuous bioreactor packed with a mixture of spongy and glass beads and inoculated with Enterobacter aerogenes. Replicated series of experimental runs were performed to study the effects of residence time on hydrogen evolution rate and to characterize the critical conditions for the wash out, as a function of the inlet glucose concentration and of the fluid superficial velocity. A further series of experimental runs was focused on the effects of both residence time and inlet glucose concentration over hydrogen productivity. A kinetic model of the process was developed and showed good agreement with experimental data, thus representing a potential tool to design a large-scale fermenter. In fact, the model was applied to the optimal design of a bioreactor suitable of feeding a phosphoric acid fuel cell of a target power. (author)

  5. Continuous Ethanol Production Using Immobilized-Cell/Enzyme Biocatalysts in Fluidized-Bed Bioreactor (FBR)

    Energy Technology Data Exchange (ETDEWEB)

    Nghiem, NP

    2003-11-16

    The immobilized-cell fluidized-bed bioreactor (FBR) was developed at Oak Ridge National Laboratory (ORNL). Previous studies at ORNL using immobilized Zymomonas mobilis in FBR at both laboratory and demonstration scale (4-in-ID by 20-ft-tall) have shown that the system was more than 50 times as productive as industrial benchmarks (batch and fed-batch free cell fermentations for ethanol production from glucose). Economic analysis showed that a continuous process employing the FBR technology to produce ethanol from corn-derived glucose would offer savings of three to six cents per gallon of ethanol compared to a typical batch process. The application of the FBR technology for ethanol production was extended to investigate more complex feedstocks, which included starch and lignocellulosic-derived mixed sugars. Economic analysis and mathematical modeling of the reactor were included in the investigation. This report summarizes the results of these extensive studies.

  6. Optimization of cyclosporin A production by Beauveria nivea in continuous fed-batch fermentation

    Directory of Open Access Journals (Sweden)

    Dong Huijun

    2011-01-01

    Full Text Available To develop the effective control method for fed-batch culture of cyclosporin A production, we chose fructose, L-valine and (NH42HPO4 as feeding nutrients and compared their productivities in relation to different concentrations. The feeding rate of three kinds of feeding materials was controlled to maintain the suitable residual concentration. The fed-batch fermentation results indicated that the optimal concentrations of fructose, L-valine and (NH42HPO4 were about 20 g/L, 0.5 g/L and 0.6 g/L for cyclosporin A production, respectively. The cultivation of Beauveria nivea could produce cyclosporin A up to 6.2 g/L for 240 hrs through a continuous feeding-rate-controlled-batch process under the optimal feeding conditions.

  7. Continuous aryl alcohol oxidase production under growth-limited conditions using a trickle bed reactor.

    Science.gov (United States)

    Pardo-Planas, Oscar; Atiyeh, Hasan K; Prade, Rolf A; Müller, Michael; Wilkins, Mark R

    2018-05-01

    An A. nidulans strain with a pyridoxine marker was used for continuous production of aryl alcohol oxidase (AAO) in a trickle bed reactor (TBR). Modified medium with reduced zinc, no copper, and 5 g/L ascorbic acid that reduced melanin production and increased AAO productivity under growth limited conditions was used. Two air flow rates, 0.11 L/min (0.1 vvm) and 1.1 L/min (1.0 vvm) were tested. More melanin formation and reduced protein productivity were observed with air flow rate of 1.1 L/min. Three random packings were used as support for the fungus inside the TBR column, two of which were hydrophobic and one which was hydrophilic, and three different dilution rates were tested. The use of GEA BCN 030 hydrophobic packing resulted in greater AAO yield and productivity than the other packings. Increasing dilution rates favored melanin formation and citric, lactic and succinic acid accumulation, which decreased AAO yield and productivity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Continuous determination of volatile products in anaerobic fermenters by on-line capillary gas chromatography

    International Nuclear Information System (INIS)

    Diamantis, V.; Melidis, P.; Aivasidis, A.

    2006-01-01

    Bio-ethanol and biogas produced during the anaerobic conversion of organic compounds has been a subject of great interest since the oil crisis of the 1970s. In ethanol fermentation and anaerobic treatment of wastewaters, end-product (ethanol) and intermediate-products (short-chain fatty acids, SCFA) cause inhibition that results in reduced process efficiency. Control of these constituents is of utmost importance for bioreactor optimization and process stability. Ethanol and SCFA can be detected with precision by capillary gas chromatography usually conducted in off-line measurements. In this work, an on-line monitoring and controlling system was developed and connected to the fermenter via an auto-sampling equipment, which could perform the feeding, filtration and dilution of the sample and final injection into the gas chromatograph through an automation-based programmed procedure. The sample was continuously pumped from the recycle stream of the bioreactor and treated using a microfiltration unit. The concentrate was returned to the reactor while the permeate was quantitatively mixed with an internal standard solution. The system comprised of a gas chromatograph with the flow cell and one-shot sampler and a PC with the appropriate software. The on-line measurement of ethanol and SCFA, directly from the liquid phase of an ethanol fermenter and a high-rate continuous mode anaerobic digester, was accomplished by gas chromatography. Also, this monitoring and controlling system was proved to be effective in the continuous fermentation of alcohol-free beer

  9. Continuous low cost transesterification process for the production of coconut biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, G.; Kumar, D.; Singh, S.; Kothari, S.; Bhatt, S.; Singh, CH. P. [Department of Chemistry, Sahu Jain College, Najibabad, 246763 (India)

    2010-07-01

    Biodiesel, or alkyl ester, is an alternative renewable, biodegradable, and non-toxic diesel fuel produced by the catalytic transesterification of vegetable oil. Here we characterize a system for continuous transesterification of vegetable oil using five continuous stirring tank reactors. We tested residence times of 16-43 min, stirring speeds of 200-800 rpm, a catalyst concentration (KOH) of 0.25-1 wt% of oil (in gram), different total flow rates of the oil and MeOH, and on the production performance of the 5 stage continuous reactor for transesterification of vegetable oil. Using a molar ratio of oil:methanol of 1:7 and a reaction temperature of 65 {sup o}C, we show that a high stirring speed increased the reaction rate, but an excessive stir speed decreased the reaction rate and conversion to biodiesel. Furthermore, a higher catalyst percentage significantly increased the reaction rate and production capacity. A catalyst percentage of 1 wt% of oil gave the best conversion; 99.04 {+-} 0.05%. The resulting biodiesel esters were characterized for their physical and fuel properties including density, viscosity, iodine volume, acid volume, cloud point, pure point, gross heat of combustion, and volatility. The purity and conversion of the biodiesel was analyzed by HPLC. (author)

  10. Optimization and characterization of biodiesel production from microalgae Botryococcus grown at semi-continuous system

    International Nuclear Information System (INIS)

    Ashokkumar, Veeramuthu; Agila, Elango; Sivakumar, Pandian; Salam, Zainal; Rengasamy, Ramasamy; Ani, Farid Nasir

    2014-01-01

    Highlights: • Bioprospecting for Botryococcus in upstream and downstream process for bioenergy production. • Large scale cultivation of B. braunii at semi-continuous system under open raceway system. • The biomass was harvested 99.5% successfully by Poly-(D)glucosamine and ferric iron. • Botryococcus biodiesel was characterized and found within ASTM standards. • Under semi-continuous mode, the alga B. braunii produces 101 tons ha −1 year −1 . - Abstract: The indigenous strain Botryococcus braunii TN101 was isolated and acclimatized under laboratory condition. Upstream and downstream process was thoroughly explored for biofuel production. During semi-continuous cultivation, the alga was grown under batch mode for 6 days; thereafter 40% of algal culture was harvested at every three days interval. At semi-continuous system, the indigenous strain grows well and produces high biomass productivity of 33.8 g m −3 day −1 . A two step combined harvesting process was designed using ferric iron and organic polymer Poly-(D)glucosamine and harvested 99.5% of biomass. Lipid extraction was optimized using different solvents, cyclohexane and methanol at 3:1 ratio supported for maximum extraction of lipids in Botryococcus up to 26.3%. Physicochemical properties of lipid was analyzed and found, saponification values 184, ester values 164, iodine values 92 and the average molecular weight of the lipids are 920 g mol −1 . The lipid contains 9.7% of FFA level, therefore, a simultaneous esterification and transesterification of free fatty acids and triacylglycerides were optimized for biodiesel production and the methyl ester yield was recorded up to 84%. In addition, an optimization study was carried out for the removal of pigments present in the biodiesel; the result revealed that 99% of pigments were removed from the biodiesel using activated charcoal. The biodiesel profile was analyzed by 1 H and 13 C NMR and GC–MS analyzer, methyl palmitate and methyl oleate

  11. Continuous ethanol production from Jerusalem artichokes stalks using immobilized cells of Kluyveromyces marxianus

    Energy Technology Data Exchange (ETDEWEB)

    Bajpai, P.; Margaritis, A.

    1986-01-01

    Continuous production of ethanol from the extract of Jerusalem artichoke stalks was investigated in a packed bed bioreactor using Kluyveromyces marxianus cells immobilized in calcium alginate gel beds. Maximum conversion of the sugars to ethanol was achieved with a yield of about 98% of the theoretical. Volumetric ethanol productivities of 102 grams of ethanol per litre per hour and 92 grams ethanol per liter per hour were obtained at 87% and 90% conversion respectively for an inlet substrate concentration of 100 gram sugars per liter. The maximum specific ethanol production rate and maximum specific total sugar uptake rate of the immobilized cells were found to be 0.96 gram ethanol per gram immobilized cells per hour and 2.06 gram sugars per gram immobilized cells per hour respectively. The immobilized cell bioreactor was run continuously at a dilution rate of 2.12 per hour for 30 days which resulted in a loss of 30% of the original activity. The half life of the bioreactor was estimated to be about 56 days.

  12. DEVELOPMENT OF CONTINUOUS SOLVENT EXTRACTION PROCESSES FOR COAL DERIVED CARBON PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    Elliot B. Kennel; R. Michael Bergen; Stephen P. Carpenter; Dady Dadyburjor; Manoj Katakdaunde; Liviu Magean; Alfred H. Stiller; W. Morgan Summers; John W. Zondlo

    2006-05-12

    The purpose of this DOE-funded effort is to develop continuous processes for solvent extraction of coal for the production of carbon products. The largest applications are those which support metals smelting, such as anodes for aluminum smelting and electrodes for arc furnaces. Other carbon products include materials used in creating fuels for the Direct Carbon Fuel Cell, metals smelting, especially in the aluminum and steel industries, as well as porous carbon structural material referred to as ''carbon foam'' and carbon fibers. During this reporting period, coking and composite fabrication continued using coal-derived samples. These samples were tested in direct carbon fuel cells. Methodology was refined for determining the aromatic character of hydro treated liquid, based on Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FTIR). Tests at GrafTech International showed that binder pitches produced using the WVU solvent extraction protocol can result in acceptable graphite electrodes for use in arc furnaces. These tests were made at the pilot scale.

  13. Continuous D-lactic acid production by a novel thermotolerant Lactobacillus delbrueckii subsp. lactis QU 41.

    Science.gov (United States)

    Tashiro, Yukihiro; Kaneko, Wataru; Sun, Yanqi; Shibata, Keisuke; Inokuma, Kentaro; Zendo, Takeshi; Sonomoto, Kenji

    2011-03-01

    We isolated and characterized a D-lactic acid-producing lactic acid bacterium (D-LAB), identified as Lactobacillus delbrueckii subsp. lactis QU 41. When compared to Lactobacillus coryniformis subsp. torquens JCM 1166 (T) and L. delbrueckii subsp. lactis JCM 1248 (T), which are also known as D-LAB, the QU 41 strain exhibited a high thermotolerance and produced D-lactic acid at temperatures of 50 °C and higher. In order to optimize the culture conditions of the QU 41 strain, we examined the effects of pH control, temperature, neutralizing reagent, and initial glucose concentration on D-lactic acid production in batch cultures. It was found that the optimal production of 20.1 g/l D-lactic acid was acquired with high optical purity (>99.9% of D-lactic acid) in a pH 6.0-controlled batch culture, by adding ammonium hydroxide as a neutralizing reagent, at 43 °C in MRS medium containing 20 g/l glucose. As a result of product inhibition and low cell density, continuous cultures were investigated using a microfiltration membrane module to recycle flow-through cells in order to improve D-lactic acid productivity. At a dilution rate of 0.87 h(-1), the high cell density continuous culture exhibited the highest D-lactic acid productivity of 18.0 g/l/h with a high yield (ca. 1.0 g/g consumed glucose) and a low residual glucose (<0.1 g/l) in comparison with systems published to date.

  14. Modifying the Toyota Production System for continuous performance improvement in an academic children's hospital.

    Science.gov (United States)

    Stapleton, F Bruder; Hendricks, James; Hagan, Patrick; DelBeccaro, Mark

    2009-08-01

    The Toyota Production System (TPS) has become a successful model for improving efficiency and eliminating errors in manufacturing processes. In an effort to provide patients and families with the highest quality clinical care, our academic children's hospital has modified the techniques of the TPS for a program in continuous performance improvement (CPI) and has expanded its application to educational and research programs. Over a period of years, physicians, nurses, residents, administrators, and hospital staff have become actively engaged in a culture of continuous performance improvement. This article provides background into the methods of CPI and describes examples of how we have applied these methods for improvement in clinical care, resident teaching, and research administration.

  15. Optimal batch production strategies under continuous price decrease and time discounting

    Directory of Open Access Journals (Sweden)

    Mandal S.

    2007-01-01

    Full Text Available Single price discount in unit cost for bulk purchasing is quite common in reality as well as in inventory literature. However, in today's high-tech industries such as personal computers and mobile industries, continuous decrease in unit cost is a regular phenomenon. In the present paper, an attempt has been made to investigate the effects of continuous price decrease and time-value of money on optimal decisions for inventoried goods having time-dependent demand and production rates. The proposed models are developed over a finite time horizon considering both shortages and without shortages in inventory. Numerical examples are taken to illustrate the developed models and to examine the sensitivity of model parameters.

  16. Solid-state fermentation: a continuous process for fungal tannase production.

    Science.gov (United States)

    van de Lagemaat, J; Pyle, D L

    2004-09-30

    Truly continuous solid-state fermentations with operating times of 2-3 weeks were conducted in a prototype bioreactor for the production of fungal (Penicillium glabrum) tannase from a tannin-containing model substrate. Substantial quantities of the enzyme were synthesized throughout the operating periods and (imperfect) steady-state conditions seemed to be achieved soon after start-up of the fermentations. This demonstrated for the first time the possibility of conducting solid-state fermentations in the continuous mode and with a constant noninoculated feed. The operating variables and fermentation conditions in the bioreactor were sufficiently well predicted for the basic reinoculation concept to succeed. However, an incomplete understanding of the microbial mechanisms, the experimental system, and their interaction indicated the need for more research in this novel area of solid-state fermentation. Copyright 2004 Wiley Periodicals, Inc.

  17. DEVELOPMENT OF CONTINUOUS SOLVENT EXTRACTION PROCESSES FOR COAL DERIVED CARBON PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    Elliot Kennel; Chong Chen; Dady Dadyburjor; Mark Heavner; Manoj Katakdaunde; Liviu Magean; James Mayberry; Alfred Stiller; Joseph Stoffa; Christopher Yurchick; John Zondlo

    2009-12-31

    This NETL sponsored effort seeks to develop continuous technologies for the production of carbon products, which may be thought of as the heavier products currently produced from refining of crude petroleum and coal tars obtained from metallurgical grade coke ovens. This effort took binder grade pitch, produced from liquefaction of West Virginia bituminous grade coal, all the way to commercial demonstration in a state of the art arc furnace. Other products, such as crude oil, anode grade coke and metallurgical grade coke were demonstrated successfully at the bench scale. The technology developed herein diverged from the previous state of the art in direct liquefaction (also referred to as the Bergius process), in two major respects. First, direct liquefaction was accomplished with less than a percent of hydrogen per unit mass of product, or about 3 pound per barrel or less. By contrast, other variants of the Bergius process require the use of 15 pounds or more of hydrogen per barrel, resulting in an inherent materials cost. Second, the conventional Bergius process requires high pressure, in the range of 1500 psig to 3000 psig. The WVU process variant has been carried out at pressures below 400 psig, a significant difference. Thanks mainly to DOE sponsorship, the WVU process has been licensed to a Canadian Company, Quantex Energy Inc, with a commercial demonstration unit plant scheduled to be erected in 2011.

  18. Continuing investigations for technology assessment of 99Mo production from LEU [low enriched Uranium] targets

    International Nuclear Information System (INIS)

    Vandergrift, G.F.; Kwok, J.D.; Marshall, S.L.; Vissers, D.R.; Matos, J.E.

    1987-01-01

    Currently much of the world's supply of /sup 99m/Tc for medical purposes is produced from 99 Mo derived from the fissioning of high enriched uranium (HEU). The need for /sup 99m/Tc is continuing to grow, especially in developing countries, where needs and national priorities call for internal production of 99 Mo. This paper presents the results of our continuing studies on the effects of substituting low enriched Uranium (LEU) for HEU in targets for the production of fission product 99 Mo. Improvements in the electrodeposition of thin films of uranium metal are reported. These improvements continue to increase the appeal for the substitution of LEU metal for HEU oxide films in cylindrical targets. The process is effective for targets fabricated from stainless steel or hastaloy. A cost estimate for setting up the necessary equipment to electrodeposit uranium metal on cylindrical targets is reported. Further investigations on the effect of LEU substitution on processing of these targets are also reported. Substitution of uranium silicides for the uranium-aluminum alloy or uranium aluminide dispersed fuel used in other current target designs will allow the substitution of LEU for HEU in these targets with equivalent 99 Mo-yield per target and no change in target geometries. However, this substitution will require modifications in current processing steps due to (1) the insolubility of uranium silicides in alkaline solutions and (2) the presence of significant quantities of silicate in solution. Results to date suggest that both concerns can be handled and that substitution of LEU for HEU can be achieved

  19. Continuous Packed Bed Reactor with Immobilized β-Galactosidase for Production of Galactooligosaccharides (GOS

    Directory of Open Access Journals (Sweden)

    Barbara Rodriguez-Colinas

    2016-11-01

    Full Text Available The β-galactosidase from Bacillus circulans was covalently attached to aldehyde-activated (glyoxal agarose beads and assayed for the continuous production of galactooligosaccharides (GOS in a packed-bed reactor (PBR. The immobilization was fast (1 h and the activity of the resulting biocatalyst was 97.4 U/g measured with o-nitrophenyl-β-d-galactopyranoside (ONPG. The biocatalyst showed excellent operational stability in 14 successive 20 min reaction cycles at 45 °C in a batch reactor. A continuous process for GOS synthesis was operated for 213 h at 0.2 mL/min and 45 °C using 100 g/L of lactose as a feed solution. The efficiency of the PBR slightly decreased with time; however, the maximum GOS concentration (24.2 g/L was obtained after 48 h of operation, which corresponded to 48.6% lactose conversion and thus to maximum transgalactosylation activity. HPAEC-PAD analysis showed that the two major GOS were the trisaccharide Gal-β(1→4-Gal-β(1→4-Glc and the tetrasaccharide Gal-β(1→4-Gal-β(1→4-Gal-β(1→4-Glc. The PBR was also assessed in the production of GOS from milk as a feed solution. The stability of the bioreactor was satisfactory during the first 8 h of operation; after that, a decrease in the flow rate was observed, probably due to partial clogging of the column. This work represents a step forward in the continuous production of GOS employing fixed-bed reactors with immobilized β-galactosidases.

  20. Anaerobic treatment of apple waste with swine manure for biogas production: Batch and continuous operation

    International Nuclear Information System (INIS)

    Kafle, Gopi Krishna; Kim, Sang Hun

    2013-01-01

    Highlights: ► Apple waste (AW) was co-digested with swine manure (SM). ► Mixture of AW and SM produced a higher biogas yield than SM only. ► Mixture of AW and SM produced a higher biogas yield at 55 °C than at 36.5 °C. ► Modified Gompertz model best fitted to the substrates used. ► Positive synergetic effect up to 33% AW during continuous digestion. -- Abstract: This study evaluated the performance of anaerobic digesters using a mixture of apple waste (AW) and swine manure (SM). Tests were performed using both batch and continuous digesters. The batch test evaluated the gas potential, gas production rate of the AW and SM (Experiment I), and the effect of AW co-digestion with SM (33:67,% volatile solids (VSs) basis) (Experiment II) at mesophilic and thermophilic temperatures. The first-order kinetic model and modified Gompertz model were also evaluated for methane yield. The continuous test evaluated the performance of a single stage completely stirred tank reactor (CSTR) with different mixture ratios of AW and SM at mesophilic temperature. The ultimate biogas and methane productivity of AW in terms of total chemical oxygen demand (TCOD) was determined to be 510 and 252 mL/g TCOD added, respectively. The mixture of AW and SM improved the biogas yield by approximately 16% and 48% at mesophilic and thermophilic temperatures, respectively, compared to the use of SM only, but no significant difference was found in the methane yield. The difference between the predicted and measured methane yield was higher with a first order kinetic model (4.6–18.1%) than with a modified Gompertz model (1.2–3.4%). When testing continuous digestion, the methane yield increased from 146 to 190 mL/g TCOD added when the AW content in the feed was increased from 25% to 33% (VS basis) at a constant organic loading rate (OLR) of 1.6 g VS/L/d and a hydraulic retention time (HRT) of 30 days. However, the total volatile fatty acids (TVFA) accumulation increased rapidly and the p

  1. 40 CFR 63.6006 - How do I demonstrate continuous compliance with the emission limits for tire cord production...

    Science.gov (United States)

    2010-07-01

    ... compliance with the emission limits for tire cord production affected sources? 63.6006 Section 63.6006... Hazardous Air Pollutants: Rubber Tire Manufacturing Continuous Compliance Requirements for Tire Cord... tire cord production affected sources? (a) You must demonstrate continuous compliance with each...

  2. Versatile, High Quality and Scalable Continuous Flow Production of Metal-Organic Frameworks

    Science.gov (United States)

    Rubio-Martinez, Marta; Batten, Michael P.; Polyzos, Anastasios; Carey, Keri-Constanti; Mardel, James I.; Lim, Kok-Seng; Hill, Matthew R.

    2014-01-01

    Further deployment of Metal-Organic Frameworks in applied settings requires their ready preparation at scale. Expansion of typical batch processes can lead to unsuccessful or low quality synthesis for some systems. Here we report how continuous flow chemistry can be adapted as a versatile route to a range of MOFs, by emulating conditions of lab-scale batch synthesis. This delivers ready synthesis of three different MOFs, with surface areas that closely match theoretical maxima, with production rates of 60 g/h at extremely high space-time yields. PMID:24962145

  3. Reaction Acceleration in Thin Films with Continuous Product Deposition for Organic Synthesis.

    Science.gov (United States)

    Wei, Zhenwei; Wleklinski, Michael; Ferreira, Christina; Cooks, R Graham

    2017-08-01

    Thin film formats are used to study the Claisen-Schmidt base-catalyzed condensation of 6-hydroxy-1-indanone with substituted benzaldehydes and to compare the reaction acceleration relative to the bulk. Relative acceleration factors initially exceeded 10 3 and were on the order of 10 2 at steady state, although the confined volume reaction was not electrostatically driven. Substituent effects were muted compared to those in the corresponding bulk and microdroplet reactions and it is concluded that the rate-limiting step at steady state is reagent transport to the interface. Conditions were found that allowed product deposition from the thin film to occur continuously as the reaction mixture was added and as the solvent evaporated. Yields of 74 % and production rates of 98 mg h -1 were reached in a very simple experimental system that could be multiplexed to greater scales. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Kaizen - continuous improvement of high voltage products; Kaizen - kontinuierliche Verbesserung bei Hochspannungsprodukten

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, M. [ABB Calor Emag Schaltanlagen AG, Hanau-Grossauheim (Germany); Goessmann, T. [ABB Calor Emag Schaltanlagen AG, Mannheim (Germany)

    1999-07-12

    In the actual global competition only the company can survive who cares for the continuous improvement of all business activities. The ABB Calor Emag Schaltanlagen AG at his production site in Hanau-Grossauheim has installed a specific improvement programm called KVP what is based on the ideas of Kaizen. Aim is the improvement of processes, mainly in production, concerning quality, dates, costs and environment by activating all colleagues. (orig.) [Deutsch] Im heutigen globalen Wettbewerb kann sich nur der behaupten, der sich kontinuierlich in allen Unternehmensbereichen weiterentwickelt. Die ABB Calor Emag Schaltanlagen AG hat in ihrem Werk Hanau-Grossauheim nach den Ideen des Kaizen ein werkspezifisches Programm zur kontinuierlichen Verbesserung der Prozesse in der Fertigung eingefuehrt. Ziel ist die stetige Verbesserung von Fertigungsparametern, wie Qualitaet, Termine, Kosten und Umwelt unter Einbeziehung aller Mitarbeiter. (orig.)

  5. Butanol production by Clostridium acetobutylicum in a continuous packed bed reactor.

    Science.gov (United States)

    Napoli, Fabio; Olivieri, Giuseppe; Russo, Maria Elena; Marzocchella, Antonio; Salatino, Piero

    2010-06-01

    In this study, we report on a butanol production process by immobilized Clostridium acetobutylicum in a continuous packed bed reactor (PBR) using Tygon rings as a carrier. The medium was a solution of lactose (15-30 g/L) and yeast extract (3 g/L) to emulate the cheese whey, an abundant lactose-rich wastewater. The reactor was operated under controlled conditions with respect to the pH and to the dilution rate. The pH and the dilution rate ranged between 4 and 5, the dilution rate between 0.54 and 2.4 h(-1) (2.5 times the maximum specific growth rate assessed for suspended cells). The optimal performance of the reactor was recorded at a dilution rate of 0.97 h(-1): the butanol productivity was 4.4 g/Lh and the selectivity of solvent in butanol was 88%(w).

  6. Studies on quantitative physiology of Trichoderma reesei with two-stage continuous culture for cellulase production

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, D; Andreotti, R; Mandels, M; Gallo, B; Reese, E T

    1979-11-01

    By employing a two-stage continuous-culture system, some of the more important physiological parameters involved in cellulase biosynthesis have been evaluated with an ultimate objective of designing an optimally controlled cellulase process. The two-stage continuous-culture system was run for a period of 1350 hr with Trichoderma reesei strain MCG-77. The temperature and pH were controlled at 32/sup 0/C and pH 4.5 for the first stage (growth) and 28/sup 0/C and pH 3.5 for the second stage (enzyme production). Lactose was the only carbon source for both stages. The ratio of specific uptake rate of carbon to that of nitrogen, Q(C)/Q(N), that supported good cell growth ranged from 11 to 15, and the ratio for maximum specific enzyme productivity ranged from 5 to 13. The maintenance coefficients determined for oxygen, M/sub 0/, and for carbon source, M/sub c/, are 0.85 mmol O/sub 2//g biomass/hr and 0.14 mmol hexose/g biomass/hr, respectively. The yield constants determined are: Y/sub X/O/ = 32.3 g biomass/mol O/sub 2/, Y/sub X/C/ = 1.1 g biomass/g C or Y/sub X/C/ = 0.44 g biomass/g hexose, Y/sub X/N/ = 12.5 g biomass/g nitrogen for the cell growth stage, and Y/sub X/N/ = 16.6 g biomass/g nitrogen for the enzyme production stage. Enzyme was produced only in the second stage. Volumetric and specific enzyme productivities obtained were 90 IU/liter/hrand 8 IU/g biomass/hr, respectively. The maximum specific enzyme productivity observed was 14.8 IU/g biomass/hr. The optimal dilution rate in the second stage that corresponded to the maximum enzyme productivity was 0.026 approx. 0.028 hr/sup -1/, and the specific growth rate in the second stage that supported maximum specific enzyme productivity was equal to or slightly less than zero.

  7. DEVELOPMENT OF CONTINUOUS SOLVENT EXTRACTION PROCESSES FOR COAL DERIVED CARBON PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    Elliot B. Kennel; Philip L. Biedler; Chong Chen; Dady Dadyburjor; Liviu Magean; Peter G. Stansberry; Alfred H. Stiller; John W. Zondlo

    2005-04-13

    The purpose of this DOE-funded effort is to develop continuous processes for solvent extraction of coal for the production of carbon products. These carbon products include materials used in metals smelting, especially in the aluminum and steel industries, as well as porous carbon structural material referred to as ''carbon foam'' and carbon fibers. A process has been developed which results in high quality binder pitch suitable for use in graphite electrodes or carbon anodes. A detailed description of the protocol is given by Clendenin. Briefly, aromatic heavy oils are hydro-treated under mild conditions in order to increase their ability to dissolve coal. An example of an aromatic heavy oil is Koppers Carbon Black Base (CBB) oil. CBB oil has been found to be an effective solvent and acceptably low cost (i.e., significantly below the market price for binder pitch, or about $280 per ton at the time of this writing). It is also possible to use solvents derived from hydrotreated coal and avoid reliance on coke oven recovery products completely if so desired.

  8. Continuous xylanase production with Aspergillus nidulans under pyridoxine limitation using a trickle bed reactor.

    Science.gov (United States)

    Müller, Michael; Prade, Rolf A; Segato, Fernando; Atiyeh, Hasan K; Wilkins, Mark R

    2015-01-01

    A trickle bed reactor (TBR) with recycle was designed and tested using Aspergillus nidulans with a pyridoxine marker and over-expressing/secreting recombinant client xylanase B (XynB). The pyridoxine marker prevented the fungus from synthesizing its own pyridoxine and fungus was unable to grow when no pyridoxine was present in the medium; however, enzyme production was unaffected. Uncontrolled mycelia growth that led to clogging of the TBR was observed when fungus without a pyridoxine marker was used for XynB production. Using the fungus with pyridoxine marker, the TBR was operated continuously for 18 days and achieved a XynB output of 41 U/ml with an influent and effluent flow rate of 0.5 ml/min and a recycle flow rate of 56 ml/min. Production yields in the TBR were 1.4 times greater than a static tray culture and between 1.1 and 67 times greater than yields for SSF enzyme production stated in the literature. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Producción de biohidrógeno a partir de residuos mediante fermentación oscura: una revisión crítica (1993-2011 Biohydrogen production from wastes via dark fermentation: a critical review (1993-2011

    Directory of Open Access Journals (Sweden)

    Sergio Andrés Blanco Londoño

    2012-12-01

    Full Text Available El hidrógeno es una energía atractiva debido a su alto contenido energético y combustión amigable. Entre los diferentes mecanismos existentes para la producción de hidrógeno, la fermentación oscura es uno de los más interesantes debido a que se aprovechan residuos como materia prima. Actualmente, la investigación en hidrógeno se encuentra en desarrollo, sin embargo, los resultados no han sido concluyentes, existiendo aún un vacío en los factores que se deben tener en cuenta y sobre todo no se ha llegado al nivel máximo de producción. En este sentido, este trabajo pretende, por medio de una revisión crítica de estudios realizados en el periodo 1993-2011, mostrar los factores más estudiados, configuraciones más empleadas y los principales resultados en este tema. Con base en esto, se encontró no sólo la necesidad de optimizar los factores que influyen en la producción, sino también la necesidad de incrementar la realización de estudios en escala real y régimen continuo.Hydrogen is an attractive energy source due to its high energy content and friendly combustion. Among the various mechanisms for hydrogen production, dark fermentation is one of the most interesting, because it uses the wastes as feedstock. The research on hydrogen production is to date in study, but the results are not yet conclusive. In this sense, this paper aims to do a critical review between 1993 and 2011 to show the most studied factors, the configurations most employed and the main results on this topic. Our findings showed the need, not only to optimize the factors that influence the production, but also to do more studies on real scale and in continuous flow.

  10. Production of continuous piezoelectric ceramic fibers for smart materials and active control devices

    Science.gov (United States)

    French, Jonathan D.; Weitz, Gregory E.; Luke, John E.; Cass, Richard B.; Jadidian, Bahram; Bhargava, Parag; Safari, Ahmad

    1997-05-01

    Advanced Cerametrics Inc. has conceived of and developed the Viscous-Suspension-Spinning Process (VSSP) to produce continuous fine filaments of nearly any powdered ceramic materials. VSSP lead zirconate titanate (PZT) fiber tows with 100 and 790 filaments have been spun in continuous lengths exceeding 1700 meters. Sintered PZT filaments typically are 10 - 25 microns in diameter and have moderate flexibility. Prior to carrier burnout and sintering, VSSP PZT fibers can be formed into 2D and 3D shapes using conventional textile and composite forming processes. While the extension of PZT is on the order of 20 microns per linear inch, a woven, wound or braided structure can contain very long lengths of PZT fiber and generate comparatively large output strokes from relatively small volumes. These structures are intended for applications such as bipolar actuators for fiber optic assembly and repair, vibration and noise damping for aircraft, rotorcraft, automobiles and home applications, vibration generators and ultrasonic transducers for medical and industrial imaging. Fiber and component cost savings over current technologies, such as the `dice-and-fill' method for transducer production, and the range of unique structures possible with continuous VSSP PZT fiber are discussed. Recent results have yielded 1-3 type composites (25 vol% PZT) with d33 equals 340 pC/N, K equals 470, and g33 equals 80 mV/N, kt equals 0.54, kp equals 0.19, dh equals 50.1pC/N and gh equals 13 mV/N.

  11. Cultivation of Chlorella protothecoides with urban wastewater in continuous photobioreactor: biomass productivity and nutrient removal.

    Science.gov (United States)

    Ramos Tercero, E A; Sforza, E; Morandini, M; Bertucco, A

    2014-02-01

    The capability to grow microalgae in nonsterilized wastewater is essential for an application of this technology in an actual industrial process. Batch experiments were carried out with the species in nonsterilized urban wastewater from local treatment plants to measure both the algal growth and the nutrient consumption. Chlorella protothecoides showed a high specific growth rate (about 1 day(-1)), and no effects of bacterial contamination were observed. Then, this microalgae was grown in a continuous photobioreactor with CO₂-air aeration in order to verify the feasibility of an integrated process of the removal of nutrient from real wastewaters. Different residence times were tested, and biomass productivity and nutrients removal were measured. A maximum of microalgae productivity was found at around 0.8 day of residence time in agreement with theoretical expectation in the case of light-limited cultures. In addition, N-NH₄ and P-PO₄ removal rates were determined in order to model the kinetic of nutrients uptake. Results from batch and continuous experiments were used to propose an integrated process scheme of wastewater treatment at industrial scale including a section with C. protothecoides.

  12. A Hierarchical structure of key performance indicators for operation management and continuous improvement in production systems.

    Science.gov (United States)

    Kang, Ningxuan; Zhao, Cong; Li, Jingshan; Horst, John A

    2016-01-01

    Key performance indicators (KPIs) are critical for manufacturing operation management and continuous improvement (CI). In modern manufacturing systems, KPIs are defined as a set of metrics to reflect operation performance, such as efficiency, throughput, availability, from productivity, quality and maintenance perspectives. Through continuous monitoring and measurement of KPIs, meaningful quantification and identification of different aspects of operation activities can be obtained, which enable and direct CI efforts. A set of 34 KPIs has been introduced in ISO 22400. However, the KPIs in a manufacturing system are not independent, and they may have intrinsic mutual relationships. The goal of this paper is to introduce a multi-level structure for identification and analysis of KPIs and their intrinsic relationships in production systems. Specifically, through such a hierarchical structure, we define and layer KPIs into levels of basic KPIs, comprehensive KPIs and their supporting metrics, and use it to investigate the relationships and dependencies between KPIs. Such a study can provide a useful tool for manufacturing engineers and managers to measure and utilize KPIs for CI.

  13. Continuing investigations for technology assessment of 99Mo production from LEU [low enriched uranium] targets

    International Nuclear Information System (INIS)

    Vandegrift, G.F.; Kwok, J.D.; Marshall, S.L.; Vissers, D.R.; Matos, J.E.

    1987-01-01

    Currently much of the world's supply of 99m Tc for medical purposes is produced from 99 Mo derived from the fissioning of high enriched uranium (HEU). This paper presents the results of our continuing studies on the effects of substituting low enriched uranium (LEU) for HEU in targets for the production of fission product 99 Mo. Improvements in the electrodeposition of thin films of uranium metal continue to increase the appeal for the substitution of LEU metal for HEU oxide films in cylindrical targets. The process is effective for targets fabricated from stainless steel or zircaloy. Included is a cost estimate for setting up the necessary equipment to electrodeposit uranium metal on cylindrical targets. Further investigations on the effect of LEU substitution on processing of these targets are also reported. Substitution of uranium silicides for the uranium-aluminium alloy or uranium aluminide dispersed fuel used in current target designs will allow the substitution of LEU for HEU in these targets with equivalent 99 Mo-yield per target and no change in target geometries. However, this substitution will require modifications in current processing steps due to 1) the insolubility of uranium silicides in alkaline solutions and 2) the presence of significant quantities of silicate in solution. Results to date suggest that substitution of LEU for HEU can be achieved. (Author)

  14. An evaluation of different bioreactor configurations for continuous bio-ethanol production

    International Nuclear Information System (INIS)

    Ntihuga, Jean Nepomuscene; Senn, Thomas; Gschwind, Peter; Kohlus, Reinhard

    2013-01-01

    Highlights: • Two bioreactor configurations were constructed and compared. • Continuous bioethanol production was performed in both bioreactors. • Plate heat exchanger bioreactor was the best for solid mash fermentation. • Operational power costs of both bioreactors were different in small scale levels. • Further study needed for both bioreactors with optimized parameters. - Abstract: In this preliminary investigation, a so-called Blenke cascade and plate heat exchanger bioreactor configuration were compared in terms of mixing characteristics, contamination free process, operational power costs and overall performance. At room temperature, fermentation was initially started as batch run and switched to continuous operation, when the residual sugars within the reactor were detected to be C ⩽ 1% (g/L). Samples from both configurations were taken and analyzed for ethanol and residual sugar content, as well as for any infection of the fermentation and lactic acid content, respectively. Mixing characteristics were studied by the residence time distribution method. Both geometries behaved as a finite number n of continuous stirred tanks in series, behaving as a plug flow with superimposed axial dispersion. The number of tanks in series n obtained in the plate heat exchanger configuration was 1.5–3 times larger than those in the Blenke cascade. The average ethanol productivity was Q p = 3.07 (g/L h) and Q p = 2.31 (g/L h) for cascade and plate exchanger configuration, respectively. The analysis of operational power costs indicates relevant differences between the two reactors at laboratory scale; however, systems with different types of pumps and viscosities are compared. From an industrial scale point of view, specific operational costs decrease with scale-up, as no mechanical mixing is needed in the fermenters

  15. Biorefineries for chemical and biofuel production

    DEFF Research Database (Denmark)

    Fjerbæk Søtoft, Lene

    crops for biofuel production is research in biorefineries using a whole-crop approach with the aim of having an optimal use of all the components of the specific crop. Looking at rape as a model crop, the components can be used for i.e. bioethanol, biodiesel, biogas, biohydrogen, feed, food and plant...

  16. Multi-electrode continuous flow microbial electrolysis cell for biogas production from acetate

    Energy Technology Data Exchange (ETDEWEB)

    Rader, Geoffrey K.; Logan, Bruce E. [Department of Civil and Environmental Engineering, Penn State University, University Park, PA 16802 (United States)

    2010-09-15

    Most microbial electrolysis cells (MECs) contain only a single set of electrodes. In order to examine the scalability of a multiple-electrode design, we constructed a 2.5 L MEC containing 8 separate electrode pairs made of graphite fiber brush anodes pre-acclimated for current generation using acetate, and 304 stainless steel mesh cathodes (64 m{sup 2}/m{sup 3}). Under continuous flow conditions and a one day hydraulic retention time, the maximum current was 181 mA (1.18 A/m{sup 2}, cathode surface area; 74 A/m{sup 3}) within three days of operation. The maximum hydrogen production (day 3) was 0.53 L/L-d, reaching an energy efficiency relative to electrical energy input of {eta}{sub E} = 144%. Current production remained relatively steady (days 3-18), but the gas composition dramatically shifted over time. By day 16, there was little H{sub 2} gas recovered and methane production increased from 0.049 L/L-d (day 3) to 0.118 L/L-d. When considering the energy value of both hydrogen and methane, efficiency relative to electrical input remained above 100% until near the end of the experiment (day 17) when only methane gas was being produced. Our results show that MECs can be scaled up primarily based on cathode surface area, but that hydrogen can be completely consumed in a continuous flow system unless methanogens can be completely eliminated from the system. (author)

  17. Multi-electrode continuous flow microbial electrolysis cell for biogas production from acetate

    KAUST Repository

    Rader, Geoffrey K.; Logan, Bruce E.

    2010-01-01

    Most microbial electrolysis cells (MECs) contain only a single set of electrodes. In order to examine the scalability of a multiple-electrode design, we constructed a 2.5 L MEC containing 8 separate electrode pairs made of graphite fiber brush anodes pre-acclimated for current generation using acetate, and 304 stainless steel mesh cathodes (64 m2/m3). Under continuous flow conditions and a one day hydraulic retention time, the maximum current was 181 mA (1.18 A/m2, cathode surface area; 74 A/m 3) within three days of operation. The maximum hydrogen production (day 3) was 0.53 L/L-d, reaching an energy efficiency relative to electrical energy input of ηE = 144%. Current production remained relatively steady (days 3-18), but the gas composition dramatically shifted over time. By day 16, there was little H2 gas recovered and methane production increased from 0.049 L/L-d (day 3) to 0.118 L/L-d. When considering the energy value of both hydrogen and methane, efficiency relative to electrical input remained above 100% until near the end of the experiment (day 17) when only methane gas was being produced. Our results show that MECs can be scaled up primarily based on cathode surface area, but that hydrogen can be completely consumed in a continuous flow system unless methanogens can be completely eliminated from the system. © 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

  18. Multi-electrode continuous flow microbial electrolysis cell for biogas production from acetate

    KAUST Repository

    Rader, Geoffrey K.

    2010-09-01

    Most microbial electrolysis cells (MECs) contain only a single set of electrodes. In order to examine the scalability of a multiple-electrode design, we constructed a 2.5 L MEC containing 8 separate electrode pairs made of graphite fiber brush anodes pre-acclimated for current generation using acetate, and 304 stainless steel mesh cathodes (64 m2/m3). Under continuous flow conditions and a one day hydraulic retention time, the maximum current was 181 mA (1.18 A/m2, cathode surface area; 74 A/m 3) within three days of operation. The maximum hydrogen production (day 3) was 0.53 L/L-d, reaching an energy efficiency relative to electrical energy input of ηE = 144%. Current production remained relatively steady (days 3-18), but the gas composition dramatically shifted over time. By day 16, there was little H2 gas recovered and methane production increased from 0.049 L/L-d (day 3) to 0.118 L/L-d. When considering the energy value of both hydrogen and methane, efficiency relative to electrical input remained above 100% until near the end of the experiment (day 17) when only methane gas was being produced. Our results show that MECs can be scaled up primarily based on cathode surface area, but that hydrogen can be completely consumed in a continuous flow system unless methanogens can be completely eliminated from the system. © 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

  19. Optimal control of hydrogen production in a continuous anaerobic fermentation bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Aceves-Lara, Cesar-Arturo [INRA, UMR792, Ingenierie des Systemes Biologiques et des Procedes, Toulouse (France); CNRS, UMR5504, Toulouse, France 135 Avenue de Rangueil, Toulouse Cedex F-31077 (France); INRA, UR050, Laboratoire de Biotechnologie de l' Environnement, Avenue des Etangs, Narbonne F-11100 (France); Latrille, Eric; Steyer, Jean-Philippe [INRA, UR050, Laboratoire de Biotechnologie de l' Environnement, Avenue des Etangs, Narbonne F-11100 (France)

    2010-10-15

    This paper addresses the problem of optimization of hydrogen production in continuous anaerobic digesters using a model predictive control (MPC) strategy. The process is described by a dynamic nonlinear model. The influent concentration of molasses together with the effluent substrate and product concentrations of acetate, propionate, butyrate and biomass were estimated by an asymptotic online observer from measurements of gas composition in H{sub 2} and CO{sub 2} and gas flow rate. The observer was tested experimentally before to apply MPC online. The combined strategy (MPC and observer) was used in order to optimize a bioreactor of 2 L. The hydrogen production was increased by 75% up to 8.27mL{sub H{sub 2}} L{sup -1}min{sup -1}, using the influent flow rate as the main control variable while keeping the conversion of the influent concentration higher than 95% and maintaining the temperature at 37 C and pH at 5.5. (author)

  20. Control of final moisture content of food products baked in continuous tunnel ovens

    Science.gov (United States)

    McFarlane, Ian

    2006-02-01

    There are well-known difficulties in making measurements of the moisture content of baked goods (such as bread, buns, biscuits, crackers and cake) during baking or at the oven exit; in this paper several sensing methods are discussed, but none of them are able to provide direct measurement with sufficient precision. An alternative is to use indirect inferential methods. Some of these methods involve dynamic modelling, with incorporation of thermal properties and using techniques familiar in computational fluid dynamics (CFD); a method of this class that has been used for the modelling of heat and mass transfer in one direction during baking is summarized, which may be extended to model transport of moisture within the product and also within the surrounding atmosphere. The concept of injecting heat during the baking process proportional to the calculated heat load on the oven has been implemented in a control scheme based on heat balance zone by zone through a continuous baking oven, taking advantage of the high latent heat of evaporation of water. Tests on biscuit production ovens are reported, with results that support a claim that the scheme gives more reproducible water distribution in the final product than conventional closed loop control of zone ambient temperatures, thus enabling water content to be held more closely within tolerance.

  1. Continuous fermentative hydrogen production from coffee drink manufacturing wastewater by applying UASB reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kyung-Won; Shin, Hang-Sik [Department of Civil and Environmental Engineering, KAIST, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Kim, Dong-Hoon [Department of Civil and Environmental Engineering, University of Windsor, 401 Sunset Ave., Essex Hall, Windsor, Ontario (Canada)

    2010-12-15

    The feasibility of continuous H{sub 2} production from coffee drink manufacturing wastewater (CDMW) was tested in two different types of reactors: a completely-stirred tank reactor (CSTR) and an up-flow anaerobic sludge blanket reactor (UASBr). While the performance in CSTR was limited, it was significantly enhanced in UASBr. The maximum H{sub 2} yield of 1.29 mol H{sub 2}/mol hexose{sub added} was achieved at HRT of 6 h in UASBr operation. Non-hydrogenic, lactic acid was the dominant in CSTR, while butyric and caproic acids in UASBr. As caproic acid is generated by consuming acetic and butyric acids, all of which are related to H{sub 2} production, the presence of caproic acid in the broth also indicates H{sub 2} production, yielding 1.33 mol H{sub 2}/glucose. It was speculated that the enhanced performance in UASBr was attributed to the high concentration of biomass over 60,000 mg VSS/L in the blanket zone, which provided insufficient substrate for indigenous lactic acid bacteria (LAB) to survive. The abundance of LAB in CDMW was confirmed by natural fermentation of CDMW. That is without the addition of external inoculum, CDMW was mainly fermented into lactic acid under mesophilic condition. For the first time ever, H{sub 2} producing granules (HPG) with diameters of 2.1 mm were successfully formed by using actual waste as a substrate. (author)

  2. Cane molasses fermentation for continuous ethanol production in an immobilized cells reactor by Saccharomyces cerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Ghorbani, Farshid; Younesi, Habibollah; Esmaeili Sari, Abbas [Department of Environmental Science, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, P.O. Box: 64414-356 (Iran); Najafpour, Ghasem [Department of Chemical Engineering, Faculty of Engineering, Noshirvani University of Technology, Babol (Iran)

    2011-02-15

    Sodium-alginate immobilized yeast was employed to produce ethanol continuously using cane molasses as a carbon source in an immobilized cell reactor (ICR). The immobilization of Saccharomyces cerevisiae was performed by entrapment of the cell cultured media harvested at exponential growth phase (16 h) with 3% sodium alginate. During the initial stage of operation, the ICR was loaded with fresh beads of mean diameter of 5.01 mm. The ethanol production was affected by the concentration of the cane molasses (50, 100 and 150 g/l), dilution rates (0.064, 0.096, 0.144 and 0.192 h{sup -1}) and hydraulic retention time (5.21, 6.94, 10.42 and 15.63 h) of the media. The pH of the feed medium was set at 4.5 and the fermentation was carried out at an ambient temperature. The maximum ethanol production, theoretical yield (Y{sub E/S}), volumetric ethanol productivity (Q{sub P}) and total sugar consumption was 19.15 g/l, 46.23%, 2.39 g l{sup -1} h{sup -1} and 96%, respectively. (author)

  3. Continuous production of biodiesel under supercritical methyl acetate conditions: Experimental investigation and kinetic model.

    Science.gov (United States)

    Farobie, Obie; Matsumura, Yukihiko

    2017-10-01

    In this study, biodiesel production by using supercritical methyl acetate in a continuous flow reactor was investigated for the first time. The aim of this study was to elucidate the reaction kinetics of biodiesel production by using supercritical methyl. Experiments were conducted at various reaction temperatures (300-400°C), residence times (5-30min), oil-to-methyl acetate molar ratio of 1:40, and a fixed pressure of 20MPa. Reaction kinetics of biodiesel production with supercritical methyl acetate was determined. Finally, biodiesel yield obtained from this method was compared to that obtained with supercritical methanol, ethanol, and MTBE (methyl tertiary-butyl ether). The results showed that biodiesel yield with supercritical methyl acetate increased with temperature and time. The developed kinetic model was found to fit the experimental data well. The reactivity of supercritical methyl acetate was the lowest, followed by that of supercritical MTBE, ethanol, and methanol, under the same conditions. Copyright © 2017. Published by Elsevier Ltd.

  4. Statistically optimized biotransformation protocol for continuous production of L-DOPA using Mucuna monosperma callus culture.

    Science.gov (United States)

    Inamdar, Shrirang Appasaheb; Surwase, Shripad Nagnath; Jadhav, Shekhar Bhagwan; Bapat, Vishwas Anant; Jadhav, Jyoti Prafull

    2013-01-01

    L-DOPA (3,4-dihydroxyphenyl-L-alanine), a modified amino acid, is an expansively used drug for the Parkinson's disease treatment. In the present study, optimization of nutritional parameters influencing L-DOPA production was attempted using the response surface methodology (RSM) from Mucuna monosperma callus. Optimization of the four factors was carried out using the Box-Behnken design. The optimized levels of factors predicted by the model include tyrosine 0.894 g l(-1), pH 4.99, ascorbic acid 31.62 mg l(-1)and copper sulphate 23.92 mg l(-1), which resulted in highest L-DOPA yield of 0.309 g l(-1). The optimization of medium using RSM resulted in a 3.45-fold increase in the yield of L-DOPA. The ANOVA analysis showed a significant R (2) value (0.9912), model F-value (112.465) and probability (0.0001), with insignificant lack of fit. Optimized medium was used in the laboratory scale column reactor for continuous production of L-DOPA. Uninterrupted flow column exhibited maximum L-DOPA production rate of 200 mg L(-1) h(-1) which is one of the highest values ever reported using plant as a biotransformation source. L-DOPA production was confirmed by HPTLC and HPLC analysis. This study demonstrates the synthesis of L- DOPA using Mucuna monosperma callus using a laboratory scale column reactor.

  5. Variability of oil and gas well productivities for continuous (unconventional) petroleum accumulations

    Science.gov (United States)

    Charpentier, Ronald R.; Cook, Troy A.

    2013-01-01

    Over the last decade, oil and gas well productivities were estimated using decline-curve analysis for thousands of wells as part of U.S. Geological Survey (USGS) studies of continuous (unconventional) oil and gas resources in the United States. The estimated ultimate recoveries (EURs) of these wells show great variability that was analyzed at three scales: within an assessment unit (AU), among AUs of similar reservoir type, and among groups of AUs with different reservoir types. Within a particular oil or gas AU (such as the Barnett Shale), EURs vary by about two orders of magnitude between the most productive wells and the least productive ones (excluding those that are dry and abandoned). The distributions of EURs are highly skewed, with most of the wells in the lower part of the range. Continuous AUs were divided into four categories based on reservoir type and major commodity (oil or gas): coalbed gas, shale gas, other low-permeability gas AUs (such as tight sands), and low-permeability oil AUs. Within each of these categories, there is great variability from AU to AU, as shown by plots of multiple EUR distributions. Comparing the means of each distribution within a category shows that the means themselves have a skewed distribution, with a range of approximately one to two orders of magnitude. A comparison of the three gas categories (coalbed gas, shale gas, and other low-permeability gas AUs) shows large overlap in the ranges of EUR distributions. Generally, coalbed gas AUs have lower EUR distributions, shale gas AUs have intermediate sizes, and the other low-permeability gas AUs have higher EUR distributions. The plot of EUR distributions for each category shows the range of variation among developed AUs in an appropriate context for viewing the historical development within a particular AU. The Barnett Shale is used as an example to demonstrate that dividing wells into groups by time allows one to see the changes in EUR distribution. Subdivision into groups

  6. [Analysis of the continuity, circulation and productivity of the Revista Española de Quimioterapia].

    Science.gov (United States)

    Gimeno Sieres, E

    2007-06-01

    The primary objective of this study was to compare some of the bibliometric indicators of the continuity, circulation and productivity of the Revista Espanola de Quimioterapia up to 2003 with other spanish journals of Pharmacy and Pharmacology. This was done by reviewing periodicals directories, such as the ISSN (International Standard Serial Number/Número Internacional Normalizado de Publicaciones Seriadas) and ULRICH'S (Periodicals Directory), as well as the CDU (Classification Universal Decimal), national and international databases including IME (Indice Médico Español), ICYT (Indice Espanol de Ciencia y Tecnologia), IPA (International Pharmaceutical Abstracts), SCI Expanded (Science Citation Index Expanded), MEDLINE (Index Medicus), EMBASE (Excerpta Medica), BIOSIS PREVIEWS, ANALYTICAL ABSTRACTS, FSTA (Food Science and Technology Abstracts), SCIFINDER SCHOLAR and CHEMISTRY CITATION INDEX. According to the results, the Revista Española de Quimioterapia, in publication for 15 years, is widely distributed and has a good rating among other scientific journals of the same discipline.

  7. Recycling of cellulases in a continuous process for production of bioethanol

    DEFF Research Database (Denmark)

    Haven, Mai Østergaard

    studies, this PhD project investigates enzyme recycling at industrial relevant conditions in the Inbicon process, e.g. high dry matter conditions and process configurations that could be implemented in large scale. The results point towards potential processes for industrial recycling of enzymes......The focus of the work presented in this thesis is recycling of commercial enzymes in a continuous process for production of bioethanol from biomass. To get a deeper understanding of the factors affecting the potential for enzyme recycling, the interactions between enzymes and biomass......, the adsorption and desorption as well as stability and recovery of activity was investigated. More knowledge on these factors have enabled a process adapted for enzyme recycling. The driver being that enzyme consumption remains a major cost when producing bioethanol from lignocellulosic biomass. Unlike previous...

  8. Continuous recycling of enzymes during production of lignocellulosic bioethanol in demonstration scale

    DEFF Research Database (Denmark)

    Haven, Mai Østergaard; Lindedam, Jane; Jeppesen, Martin D.

    2015-01-01

    Recycling of enzymes in production of lignocellulosic bioethanol has been tried for more than 30 years. So far, the successes have been few and the experiments have been carried out at conditions far from those in an industrially feasible process. Here we have tested continuous enzyme recycling a...... broth also opens up the possibility of lowering the dry matter content in hydrolysis and fermentation while still maintaining high ethanol concentrations....... at demonstration scale using industrial process conditions (high dry matter content and low enzyme dosage) for a period of eight days. The experiment was performed at the Inbicon demonstration plant (Kalundborg, Denmark) capable of converting four tonnes of wheat straw per hour. 20% of the fermentation broth...... was recycled to the hydrolysis reactor while enzyme dosage was reduced by 5%. The results demonstrate that recycling enzymes by this method can reduce overall enzyme consumption and may also increase the ethanol concentrations in the fermentation broth. Our results further show that recycling fermentation...

  9. Continuous fermentation using low concentration of sugar cane and Zymomonas mobilis CP4 for ethanol production

    Directory of Open Access Journals (Sweden)

    João Batista Buzato

    2001-01-01

    Full Text Available Effect of dilution rate in continuous fermentation of 20g sucrose/L and Z. mobilis CP4 was studied for ethanol production at 28oC + 1, without pH control. Four dilution rates were compared: 0.045; 0.14; 0.23 and 0.34 h-1. In dilution rates 0.045; 0.14 and 0.23 h-1 were produced 9,4g/L of ethanol and in dilution rate 0.34 h-1 was produced 8,8 g/L. Ethanol conversion efficiency were of 91% in dilution rates 0.045; 0.14 and 0. 23 h-1. In dilution rate 0.34 h-1 the conversion efficiency was of 85%.

  10. Role of continual environmental performance improvement in achieving sustainability in uranium production

    International Nuclear Information System (INIS)

    Jarrell, J.P.; Chad, G.M.S.

    2002-01-01

    Although the term sustainable development is commonly used today, there is not yet a commonly accepted definition. Various ways of measuring sustainability have been proposed. To show how these issues are being effectively addressed in modern uranium developments, we will review some methods of defining the environmental component of sustainable development in the mining and mineral-processing sector. Environmental impacts associated with uranium extraction and processing in modern facilities are modest. Air and water emissions are well controlled. Waste materials are subject to comprehensive management programmes. The size of the impacted area is smaller than in other energy sectors, providing good opportunity to minimize land impact. Experience over the past three decades facilitated gradual, persistent, but cumulatively significant environmental improvements in the uranium production sector. Cameco's uranium mining and processing facilities exemplify these improvements. These improvements can be expected to continue, supporting our argument of Cameco's environmental sustainability. (author)

  11. Process analytical technology in continuous manufacturing of a commercial pharmaceutical product.

    Science.gov (United States)

    Vargas, Jenny M; Nielsen, Sarah; Cárdenas, Vanessa; Gonzalez, Anthony; Aymat, Efrain Y; Almodovar, Elvin; Classe, Gustavo; Colón, Yleana; Sanchez, Eric; Romañach, Rodolfo J

    2018-03-01

    The implementation of process analytical technology and continuous manufacturing at an FDA approved commercial manufacturing site is described. In this direct compaction process the blends produced were monitored with a Near Infrared (NIR) spectroscopic calibration model developed with partial least squares (PLS) regression. The authors understand that this is the first study where the continuous manufacturing (CM) equipment was used as a gravimetric reference method for the calibration model. A principal component analysis (PCA) model was also developed to identify the powder blend, and determine whether it was similar to the calibration blends. An air diagnostic test was developed to assure that powder was present within the interface when the NIR spectra were obtained. The air diagnostic test as well the PCA and PLS calibration model were integrated into an industrial software platform that collects the real time NIR spectra and applies the calibration models. The PCA test successfully detected an equipment malfunction. Variographic analysis was also performed to estimate the sampling analytical errors that affect the results from the NIR spectroscopic method during commercial production. The system was used to monitor and control a 28 h continuous manufacturing run, where the average drug concentration determined by the NIR method was 101.17% of label claim with a standard deviation of 2.17%, based on 12,633 spectra collected. The average drug concentration for the tablets produced from these blends was 100.86% of label claim with a standard deviation of 0.4%, for 500 tablets analyzed by Fourier Transform Near Infrared (FT-NIR) transmission spectroscopy. The excellent agreement between the mean drug concentration values in the blends and tablets produced provides further evidence of the suitability of the validation strategy that was followed. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Continuous Production of Ethanol from Starch Using Glucoamylase and Yeast Co-Immobilized in Pectin Gel

    Science.gov (United States)

    Giordano, Raquel L. C.; Trovati, Joubert; Schmidell, Willibaldo

    This work presents a continuous simultaneous saccharification and fermentation (SSF) process to produce ethanol from starch using glucoamylase and Saccharomyces cerevisiae co-immobilized in pectin gel. The enzyme was immobilized on macroporous silica, after silanization and activation of the support with glutaraldehyde. The silicaenzyme derivative was co-immobilized with yeast in pectin gel. This biocatalyst was used to produce ethanol from liquefied manioc root flour syrup, in three fixed bed reactors. The initial reactor yeast load was 0.05 g wet yeast/ml of reactor (0.1 g wet yeast/g gel), used in all SSF experiments. The enzyme concentration in the reactor was defined by running SSF batch assays, using different amount of silica-enzyme derivative, co-immobilized with yeast in pectin gel. The chosen reactor enzyme concentration, 3.77 U/ml, allowed fermentation to be the rate-limiting step in the batch experiment. In this condition, using initial substrate concentration of 166.0 g/1 of total reducing sugars (TRS), 1 ml gel/1 ml of medium, ethanol productivity of 8.3 g/l/h was achieved, for total conversion of starch to ethanol and 91% of the theoretical yield. In the continuous runs, feeding 163.0 g/1 of TRS and using the same enzyme and yeast concentrations used in the batch run, ethanol productivity was 5.9 g ethanol/1/h, with 97% of substrate conversion and 81% of the ethanol theoretical yield. Diffusion effects in the extra-biocatalyst film seemed to be reduced when operating at superficial velocities above 3.7 × 10-4 cm/s.

  13. Biocatalysis and bacterial cells; problems and prospects for biohydrogen

    International Nuclear Information System (INIS)

    Hallenbeck, P.C.; Viger, J.-F.

    2000-01-01

    Biological hydrogen production, studied in a number of model and small-scale systems over the last twenty-five years, has been advanced as a potential technology for producing clean energy. However, the rates and efficiencies of hydrogen production by any system fall far short of economic feasibility at present. A number of different systems have been proposed and studied including direct biophotolytic processes and two stage systems. Direct biophotolytic processes, though inherently attractive, suffer from the perhaps insurmountable barriers of the oxygen sensitivity of the enzymes involved and intrinsic limitations in light conversion efficiencies. Fermentative processes, using either biomass obtained in a first stage light conversion process or perhaps more attractively, various waste streams, present an interesting yet largely unexplored avenue for the biological production of hydrogen. Much is presently known about the molecular biology and biochemistry of the hydrogen producing enzymes, reductant generating systems, and physiology of many hydrogen producing organisms. The potential of metabolic engineering for redirecting electron flux to hydrogen production is discussed. Some of the relevant details of hydrogen evolving systems are reviewed in the hopes of identifying potentially limiting factors and therefore indicating directions for future research aimed at increasing production rates and conversion efficiencies to economically feasible levels. (author)

  14. Continuous recycling of enzymes during production of lignocellulosic bioethanol in demonstration scale

    International Nuclear Information System (INIS)

    Haven, Mai Østergaard; Lindedam, Jane; Jeppesen, Martin Dan; Elleskov, Michael; Rodrigues, Ana Cristina; Gama, Miguel; Jørgensen, Henning; Felby, Claus

    2015-01-01

    Highlights: • Results from continuous experiments in demonstration scale for a total of 16 days. • Reuse of enzymes is possible through recycling fermentation broth. • Recycling fermentation broth can increase ethanol concentration with lower dry matter. - Abstract: Recycling of enzymes in production of lignocellulosic bioethanol has been tried for more than 30 years. So far, the successes have been few and the experiments have been carried out at conditions far from those in an industrially feasible process. Here we have tested continuous enzyme recycling at demonstration scale using industrial process conditions (high dry matter content and low enzyme dosage) for a period of eight days. The experiment was performed at the Inbicon demonstration plant (Kalundborg, Denmark) capable of converting four tonnes of wheat straw per hour. 20% of the fermentation broth was recycled to the hydrolysis reactor while enzyme dosage was reduced by 5%. The results demonstrate that recycling enzymes by this method can reduce overall enzyme consumption and may also increase the ethanol concentrations in the fermentation broth. Our results further show that recycling fermentation broth also opens up the possibility of lowering the dry matter content in hydrolysis and fermentation while still maintaining high ethanol concentrations.

  15. PRELIMINARY DESIGN OF OSCILLATORY FLOW BIODIESEL REACTOR FOR CONTINUOUS BIODIESEL PRODUCTION FROM JATROPHA TRIGLYCERIDES

    Directory of Open Access Journals (Sweden)

    AZHARI T. I. MOHD. GHAZI

    2008-08-01

    Full Text Available The concept of a continuous process in producing biodiesel from jatropha oil by using an Oscillatory Flow Biodiesel Reactor (OFBR is discussed in this paper. It has been recognized that the batch stirred reactor is a primary mode used in the synthesis of biodiesel. However, pulsatile flow has been extensively researcehed and the fundamental principles have been successfully developed upon which its hydrodynamics are based. Oscillatory flow biodiesel reactor offers precise control of mixing by means of the baffle geometry and pulsation which facilitates to continuous operation, giving plug flow residence time distribution with high turbulence and enhanced mass and heat transfer. In conjunction with the concept of reactor design, parameters such as reactor dimensions, the hydrodynamic studies and physical properties of reactants must be considered prior to the design work initiated recently. The OFBR reactor design involves the use of simulation software, ASPEN PLUS and the reactor design fundamentals. Following this, the design parameters shall be applied in fabricating the OFBR for laboratory scale biodiesel production.

  16. Production of acids and alcohols from syngas in a two-stage continuous fermentation process.

    Science.gov (United States)

    Abubackar, Haris Nalakath; Veiga, María C; Kennes, Christian

    2018-04-01

    A two-stage continuous system with two stirred tank reactors in series was utilized to perform syngas fermentation using Clostridium carboxidivorans. The first bioreactor (bioreactor 1) was maintained at pH 6 to promote acidogenesis and the second one (bioreactor 2) at pH 5 to stimulate solventogenesis. Both reactors were operated in continuous mode by feeding syngas (CO:CO 2 :H 2 :N 2 ; 30:10:20:40; vol%) at a constant flow rate while supplying a nutrient medium at different flow rates of 8.1, 15, 22 and 30 ml/h. A cell recycling unit was added to bioreactor 2 in order to recycle the cells back to the reactor, maintaining the OD 600 around 1 in bioreactor 2 throughout the experimental run. When comparing the flow rates, the best results in terms of solvent production were obtained with a flow rate of 22 ml/h, reaching the highest average outlet concentration for alcohols (1.51 g/L) and the most favorable alcohol/acid ratio of 0.32. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Continuing Discontinuities: Local and State Perspectives on Cattle Production and Water Management in Botswana

    Directory of Open Access Journals (Sweden)

    Emmanuel Manzungu

    2009-06-01

    Full Text Available From 1885 when the modern state of Botswana was founded until the discovery of significant mineral deposits in 1967, one year after independence, the livestock industry, particularly cattle production, played a significant role in the country’s economy. Today there are concerns about how the livestock industry, because of its importance to many rural households, and its potential to diversify the mineral-dominated economy, can be revived. In recognition of the country’s semi-arid climate, the government has promoted a policy of developing water sources for livestock watering. The state has acknowledged the policy has largely been ineffective, but continues to implement it. This paper attempts to explain this paradox by examining state and local perspectives in the management of water and related resources in the Botswana part of the Limpopo river basin. The discontinuities between the local inhabitants and state practitioners are analyzed within the wider physical social, political, and economic landscape. We ascribe the continued implementation of an ineffective policy to modernisation claims.

  18. ON A REDUCED CROSSED PRODUCT OF A GROUP BY A C*-ALGEBRA. THE CASES OF CONTINUOUS TRACE AND TYPE I REDUCED CROSSED PRODUCT

    OpenAIRE

    Daniel Tudor

    2014-01-01

    This paper analyzes two special cases of C* -algebras, the cases of universal crossed product and reduced crossed product of a group by a C* -algebra. In the hypothesis that the universal crossed product is a continuous trace C* -algebra or a type I C* -algebra, it is proved that the reduced crossed product is a continuous trace C* -algebra or, respectively, a type I C* -algebra. Moreover, these results can be extended in the case when the crossed products are obtained from a groupoid an...

  19. The continuous process – social production of architecture in Hestnes Ferreira

    Directory of Open Access Journals (Sweden)

    Alexandra Saraiva

    2018-05-01

    Full Text Available This article aims at describing the continuous process in the social production of the architecture of Raúl Hestnes Ferreira. The neorealist ideology defended by his father and followed by the family, as well as the values of freedom, democracy and respect for the others, built his personality and his humanistic character. His cross-cultural career in Portugal, Finland and the United States of America was instrumental in building his architectural lexicon. In order to illustrate these influences, four housing works with different conceptual dimensions are presented such as laboratorial experiments: the José Gomes Ferreira House in Albarraque (1960-1961, the Twin Housing in Queijas (1967-1973, finishing with the presentation of two social housing experiences, namely, the neighborhood Fonsecas and Calçada (1974-1986 under the SAAL project in Lisbon and the João Barbeiro Housing Unit (1978-1987 in Beja. In Hestnes Ferreira, the social production of architecture was not a consequence, nor an anticipation, but a fact that by the simultaneity, defined and characterized his architecture.

  20. Segregation of Elements in Continuous Cast Carbon Steel Billets Designated for Long Products

    Directory of Open Access Journals (Sweden)

    Hutny A. M.

    2016-12-01

    Full Text Available This article presents research results concerning designation of the scope of segregation of elements by analysing the ingot, designated for hot rolling of long products. The research tests were performed under industrial conditions, during continuous casting production cycle of high carbon steels. From cc ingots with square cross-section of 160 mm samples having the length of 400 mm were collected, out of which two samples were cut up, the so-called templates with the thickness of 20 mm. Segregation of elements was determined based on the quantitative analysis of results performed by using spark spectrometry pursuant to PN-H-04045. Changes in concentrations of elements were analysed along the line, which join the opposite sides of the sample in their half length and pass through the geometric centre of the square cross-section. In the further course of the research study, there was also determined the segregation along perpendicular line up to the surface connecting the core of the cross-section with lateral plane. Designations of element contents were performed at points distanced from each other by approx. 10 mm and situated on the lines. There was found segregation of carbon, sulphur and phosphorus.

  1. Control of algal production in a high rate algal pond: investigation through batch and continuous experiments.

    Science.gov (United States)

    Derabe Maobe, H; Onodera, M; Takahashi, M; Satoh, H; Fukazawa, T

    2014-01-01

    For decades, arid and semi-arid regions in Africa have faced issues related to water availability for drinking, irrigation and livestock purposes. To tackle these issues, a laboratory scale greywater treatment system based on high rate algal pond (HRAP) technology was investigated in order to guide the operation of the pilot plant implemented in the 2iE campus in Ouagadougou (Burkina Faso). Because of the high suspended solids concentration generally found in effluents of this system, the aim of this study is to improve the performance of HRAPs in term of algal productivity and removal. To determine the selection mechanism of self-flocculated algae, three sets of sequencing batch reactors (SBRs) and three sets of continuous flow reactors (CFRs) were operated. Despite operation with the same solids retention time and the similarity of the algal growth rate found in these reactors, the algal productivity was higher in the SBRs owing to the short hydraulic retention time of 10 days in these reactors. By using a volume of CFR with twice the volume of our experimental CFRs, the algal concentration can be controlled during operation under similar physical conditions in both reactors.

  2. Continuous production of biodiesel from microalgae by extraction coupling with transesterification under supercritical conditions.

    Science.gov (United States)

    Zhou, Dan; Qiao, Baoquan; Li, Gen; Xue, Song; Yin, Jianzhong

    2017-08-01

    Raw material for biodiesel has been expanded from edible oil to non-edible oil. In this study, biodiesel continuous production for two kinds of microalgae Chrysophyta and Chlorella sp. was conducted. Coupling with the supercritical carbon dioxide extraction, the oil of microalgae was extracted firstly, and then sent to the downstream production of biodiesel. The residue after decompression can be reused as the material for pharmaceuticals and nutraceuticals. Results showed that the particle size of microalgae, temperature, pressure, molar ration of methanol to oil, flow of CO 2 and n-hexane all have effects on the yield of biodiesel. With the optimal operation conditions: 40mesh algae, extraction temperature 60°C, flow of n-hexane 0.4ml/min, reaction temperature: 340°C, pressure: 18-20MPa, CO 2 flow of 0.5L/min, molar ration of methanol to oil 84:1, a yield of 56.31% was obtained for Chrysophyta, and 63.78% for Chlorella sp. due to the higher lipid content. Copyright © 2017. Published by Elsevier Ltd.

  3. Cyanobacterial hydrogenases and biohydrogen: present status and future potential

    International Nuclear Information System (INIS)

    Lindblad, P.; Tamagnini, P.

    2000-01-01

    Molecular hydrogen (H 2 ) is an environmentally clean energy-carrier that may be a valuable alternative to the limited fossil fuel resources of today. For photobiological H 2 production, photosynthetic cyanobacteria are among the ideal candidates since they have the simplest nutritional requirements: they can grow in air (N 2 and CO 2 ), water (electrons and reductant), and mineral salts with light (solar energy) as the only source of energy. In N 2 -fixing cyanobacteria, H 2 is mainly produced by nitrogenases, but its partial consumption is quickly catalyzed by a unidirectional uptake hydrogenase. In addition, a bidirectional (reversible) enzyme may also oxidize some of the molecular hydrogen. The same enzyme will, under certain conditions, evolve H 2 Filamentous cyanobacteria have been used in bioreactors for the photobiological conversion of water to hydrogen. However, the conversion efficiencies achieved are low because the net H 2 production is the result of H 2 evolution via a nitrogenase and H 2 consumption mainly via an uptake hydrogenase. Consequently, the improvements of the conversion efficiencies are achieved e.g. through the optimization of the conditions for H 2 evolution by nitrogenase, through the production of mutants deficient in H 2 uptake activity and by an increased H 2 -evolution by a bidirectional enzyme. Symbiotic cells are of fundamental interest since they in situ 'function as a bioreactor', High metabolism, transfer of metabolite(s) from symbiont to host but almost no growth. In the present communication we will present the general knowledge about hydrogen metabolism/hydrogenases in filamentous cyanobacteria focusing on recent advances using molecular techniques, outline strategies for improving the capacity of H 2 -production by filamentous strains, and stress the importance of international cooperations and networks. (author)

  4. A continuous time inventory model for a product recovery system with multiple options

    NARCIS (Netherlands)

    Kleber, R.; Minner, S.; Kiesmüller, G.P.

    2002-01-01

    Increasing environmental consciousness, limited availability of natural resources to manufacture new products, recovery quotas to avoid disposal, manufacturers assigned to be responsible for used products, and materials value of components included in returned products are incentives for product

  5. Experimental study on methanol recovery through flashing vaporation in continuous production of biodiesel via supercritical methanol

    International Nuclear Information System (INIS)

    Wang Cunwen; Chen Wen; Wang Weiguo; Wu Yuanxin; Chi Ruan; Tang Zhengjiao

    2011-01-01

    To improve the oil conversion, high methanol/oil molar ratio is required in the continuous production of biodiesel via supercritical methanol transesterification in tubular reactor. And thus the subsequent excess methanol recovery needs high energy consumption. Based on the feature of high temperature and high pressure in supercritical methanol transesterification, excess methanol recovery in reaction system by flashing vaporation is conducted and the effect of reaction temperature, reaction pressure and flashing pressure on methanol recovery and methanol concentration in gas phase is discussed in detail in this article. Results show that at the reaction pressure of 9-15 MPa and the reaction temperature of 240-300 o C, flashing pressure has significant influence on methanol recovery and methanol content in gas phase, which can be effectively improved by reducing flashing pressure. At the same time, reaction temperature and reaction pressure also have an important effect on methanol recovery and methanol content in gas phase. At volume flow of biodiesel and methanol 1:2, tubular reactor pressure 15 MPa, tubular reactor temperature 300 o C and the flashing pressure 0.4 MPa, methanol recovery is more than 85% and methanol concentration of gas phase (mass fraction) is close to 99% after adiabatic braising; therefore, the condensate liquid of gas phase can be injected directly into methanol feedstock tank to be recycled. Research abstracts: Biodiesel is an important alternative energy, and supercritical methanol transesterification is a new and green technology to prepare biodiesel with some obvious advantages. But it also exists some problems: high reaction temperature, high reaction pressure and large molar ratio of methanol/oil will cause large energy consumption which restricts supercritical methanol for the industrial application of biodiesel. So a set of tubular reactor-coupled flashing apparatus is established for continuous preparing biodiesel in supercritical

  6. Production of extracellular protease and glucose uptake in Bacillus clausii in steady-state and transient continuous cultures

    DEFF Research Database (Denmark)

    Christiansen, Torben; Nielsen, Jens

    2002-01-01

    The production of the extracellular alkaline protease Savinase(R) (EC 3.4.21.62) and glucose uptake in a non-sporulating strain of Bacillus clausii were investigated by analysing steady-state and transients during continuous cultivations. The specific production rate was found to have an optimum...

  7. Growth and enzyme production during continuous cultures of a high amylase-producing variant of Aspergillus oryzae

    DEFF Research Database (Denmark)

    Zangirolami, Teresa; Carlsen, M.; Nielsen, J.

    2002-01-01

    Growth and product formation by a selected variant of Aspergillus oryzae showing high alpha-amylase production was studied in continuous cultivations carried out at six different specific growth rates, using glucose as the growth-limiting nutrient. The analysis of the steady-state data revealed...

  8. Impact of different satellite soil moisture products on the predictions of a continuous distributed hydrological model

    Science.gov (United States)

    Laiolo, P.; Gabellani, S.; Campo, L.; Silvestro, F.; Delogu, F.; Rudari, R.; Pulvirenti, L.; Boni, G.; Fascetti, F.; Pierdicca, N.; Crapolicchio, R.; Hasenauer, S.; Puca, S.

    2016-06-01

    The reliable estimation of hydrological variables in space and time is of fundamental importance in operational hydrology to improve the flood predictions and hydrological cycle description. Nowadays remotely sensed data can offer a chance to improve hydrological models especially in environments with scarce ground based data. The aim of this work is to update the state variables of a physically based, distributed and continuous hydrological model using four different satellite-derived data (three soil moisture products and a land surface temperature measurement) and one soil moisture analysis to evaluate, even with a non optimal technique, the impact on the hydrological cycle. The experiments were carried out for a small catchment, in the northern part of Italy, for the period July 2012-June 2013. The products were pre-processed according to their own characteristics and then they were assimilated into the model using a simple nudging technique. The benefits on the model predictions of discharge were tested against observations. The analysis showed a general improvement of the model discharge predictions, even with a simple assimilation technique, for all the assimilation experiments; the Nash-Sutcliffe model efficiency coefficient was increased from 0.6 (relative to the model without assimilation) to 0.7, moreover, errors on discharge were reduced up to the 10%. An added value to the model was found in the rainfall season (autumn): all the assimilation experiments reduced the errors up to the 20%. This demonstrated that discharge prediction of a distributed hydrological model, which works at fine scale resolution in a small basin, can be improved with the assimilation of coarse-scale satellite-derived data.

  9. A prototype data assimilation framework for generating spatiotemporally continuous SWOT data products

    Science.gov (United States)

    Andreadis, K.; Margulis, S. A.; Li, D.; Lettenmaier, D. P.

    2017-12-01

    The Surface Water and Ocean Topography (SWOT) satellite will provide critical surface water observations for the hydrologic community. However, production of key SWOT variables, such as river discharge and surface inundation, as well as lake, reservoir, and wetland storage change will be complicated by the discontinuity of the observations in space and time. A methodology that generates products with spatially and temporally continuous fields based on SWOT observables would be highly desirable. Data assimilation provides a mechanism for merging observations from SWOT with model predictions in order to produce estimates of quantities such as river discharge, storage change, and water heights for locations and times when there is no satellite overpass or other constraints (such as layover) render the measurement unusable. We describe here a prototype assimilation system with application to the Upper Mississippi basin, implemented using synthetic SWOT observations. We use a hydrologic model (VIC) coupled with a hydrodynamic model (LISFLOOD-FP) which generates "true" fields of surface water variables. The true fields are then used to generate synthetic SWOT observations using the SWOT Instrument Simulator. We also perform a "first-guess" (or open-loop) simulation with the coupled model using a configuration that contains errors representative of the imperfect knowledge of parameters and input data, including channel topography, bankfull widths and depths, and inflows, to create an ensemble of 20 model trajectories. Subsequently we assimilate the synthetic SWOT observations into the open-loop model results to estimate water surface elevation, discharge, and storage change. Our preliminary results using three data assimilation strategies show that all improve the water surface elevation estimate accuracy by 25% - 35% for a river reach of the upper Mississippi River. Ongoing work is examining whether the improved water surface elevation estimates propagate to improvements

  10. Evaluating continuous application of treated sludge on soil and plant productivity

    Directory of Open Access Journals (Sweden)

    Ahmed Al-Busaidi

    2018-01-01

    Full Text Available Kala Compost is a mixture of treated sewage bio-solids and green wastes. It can improve soil fertility and plant growth. However, long-term application of treated sewage bio-solids could result in heavy metals accumulation and some health problems. e objective of this study was to evaluate the e ect of a long run application of Kala compost mixed with chemical fertilizer on soil and plant productivity. Soil and plant (mainly cucumber samples were taken from 12 greenhouses that received Kala compost continuously for the last ve years. No symptoms of physical or chemical problems were observed in the greenhouses and measured soil samples. Moreover, the soil had su cient values of di erent nutrients for plant growth and all measured micronutrients (heavy metals were within the safe limit and below the range of the international standards. An excellent growth was observed in all grown plants and no symptoms of elements de ciency were found. Chemical analysis of fruit samples did not show any accumulation of heavy metals and all measured elements were within the safe limit and did not exceed the international standards. It can be concluded that Kala compost was a good media for plant growth that can enrich the soil with di erent elements needed for higher yield. However, more monitoring is needed with treated bio-solid application but good management could be the key to avoid any adverse e ect of any contaminant.

  11. Continuous-Flow Production of Injectable Liposomes via a Microfluidic Approach

    Science.gov (United States)

    Zizzari, Alessandra; Bianco, Monica; Perrone, Elisabetta; Amato, Francesco; Maruccio, Giuseppe; Rendina, Filippo; Arima, Valentina

    2017-01-01

    Injectable liposomes are characterized by a suitable size and unique lipid mixtures, which require time-consuming and nonstraightforward production processes. The complexity of the manufacturing methods may affect liposome solubility, the phase transition temperatures of the membranes, the average particle size, and the associated particle size distribution, with a possible impact on the drug encapsulation and release. By leveraging the precise steady-state control over the mixing of miscible liquids and a highly efficient heat transfer, microfluidic technology has proved to be an effective and direct methodology to produce liposomes. This approach results particularly efficient in reducing the number of the sizing steps, when compared to standard industrial methods. Here, Microfluidic Hydrodynamic Focusing chips were produced and used to form liposomes upon tuning experimental parameters such as lipids concentration and Flow-Rate-Ratios (FRRs). Although modelling evidenced the dependence of the laminar flow on the geometric constraints and the FRR conditions, for the specific formulation investigated in this study, the lipids concentration was identified as the primary factor influencing the size of the liposomes and their polydispersity index. This was attributed to a predominance of the bending elasticity modulus over the vesiculation index in the lipid mixture used. Eventually, liposomes of injectable size were produced using microfluidic one-pot synthesis in continuous flow. PMID:29232873

  12. Microorganism selection and biosurfactant production in a continuously and periodically operated bioslurry reactor.

    Science.gov (United States)

    Cassidy, D P; Hudak, A J

    2001-06-29

    A continuous-flow reactor (CSTR) and a soil slurry-sequencing batch reactor (SS-SBR) were maintained in 8l vessels for 180 days to treat a soil contaminated with diesel fuel (DF). Concentrations of Candida tropicalis, Brevibacterium casei, Flavobacterium aquatile, Pseudomonas aeruginosa, and Pseudomonas fluorescens were determined using fatty acid methyl ester (FAME) analysis. DF removal (biological and volatile) and biosurfactant concentrations were measured. The SS-SBR encouraged the growth of biosurfactant-producing species relative to the CSTR. Counts of biosurfactant-producing species (C. tropicalis, P. aeruginosa, P. fluorescens) relative to total microbial counts were 88% in the SS-SBR and 23% in the CSTR. Biosurfactants were produced in the SS-SBR to levels of nearly 70 times the critical micelle concentration (CMC) early in the cycle, but were completely degraded by the end of each cycle. No biosurfactant production was observed in the CSTR. DF biodegradation rates were over 40% greater and DF stripping was over five times lower in the SS-SBR than the CSTR. However, considerable foaming occurred in the SS-SBR. Reversing the mode of operation in the reactors on day 80 caused a complete reversal in microbial consortia and reactor performance by day 120. These results show that bioslurry reactor operation can be manipulated to control overall reactor performance.

  13. Continuous-Flow Production of Injectable Liposomes via a Microfluidic Approach

    Directory of Open Access Journals (Sweden)

    Alessandra Zizzari

    2017-12-01

    Full Text Available Injectable liposomes are characterized by a suitable size and unique lipid mixtures, which require time-consuming and nonstraightforward production processes. The complexity of the manufacturing methods may affect liposome solubility, the phase transition temperatures of the membranes, the average particle size, and the associated particle size distribution, with a possible impact on the drug encapsulation and release. By leveraging the precise steady-state control over the mixing of miscible liquids and a highly efficient heat transfer, microfluidic technology has proved to be an effective and direct methodology to produce liposomes. This approach results particularly efficient in reducing the number of the sizing steps, when compared to standard industrial methods. Here, Microfluidic Hydrodynamic Focusing chips were produced and used to form liposomes upon tuning experimental parameters such as lipids concentration and Flow-Rate-Ratios (FRRs. Although modelling evidenced the dependence of the laminar flow on the geometric constraints and the FRR conditions, for the specific formulation investigated in this study, the lipids concentration was identified as the primary factor influencing the size of the liposomes and their polydispersity index. This was attributed to a predominance of the bending elasticity modulus over the vesiculation index in the lipid mixture used. Eventually, liposomes of injectable size were produced using microfluidic one-pot synthesis in continuous flow.

  14. Single-Step Fabrication of Computationally Designed Microneedles by Continuous Liquid Interface Production.

    Directory of Open Access Journals (Sweden)

    Ashley R Johnson

    Full Text Available Microneedles, arrays of micron-sized needles that painlessly puncture the skin, enable transdermal delivery of medications that are difficult to deliver using more traditional routes. Many important design parameters, such as microneedle size, shape, spacing, and composition, are known to influence efficacy, but are notoriously difficult to alter due to the complex nature of microfabrication techniques. Herein, we utilize a novel additive manufacturing ("3D printing" technique called Continuous Liquid Interface Production (CLIP to rapidly prototype sharp microneedles with tuneable geometries (size, shape, aspect ratio, spacing. This technology allows for mold-independent, one-step manufacturing of microneedle arrays of virtually any design in less than 10 minutes per patch. Square pyramidal CLIP microneedles composed of trimethylolpropane triacrylate, polyacrylic acid and photopolymerizable derivatives of polyethylene glycol and polycaprolactone were fabricated to demonstrate the range of materials that can be utilized within this platform for encapsulating and controlling the release of therapeutics. These CLIP microneedles effectively pierced murine skin ex vivo and released the fluorescent drug surrogate rhodamine.

  15. GROWTH AND ENZYME PRODUCTION DURING CONTINUOUS CULTURES OF A HIGH AMYLASE-PRODUCING VARIANT OF Aspergillus Oryzae

    OpenAIRE

    Zangirolami,T.C.; Carlsen,M.; Nielsen,J.; Jørgensen,S.B.

    2002-01-01

    Growth and product formation by a selected variant of Aspergillus oryzae showing high alpha-amylase production was studied in continuous cultivations carried out at six different specific growth rates, using glucose as the growth-limiting nutrient. The analysis of the steady-state data revealed that the variant and wild-type strains were similar with respect to glucose uptake system and stoichiometric coefficients. However, the variant was capable of maintaining an enzyme production as high a...

  16. Continuous production of glycerol by catalytic high pressure hydrogenolysis of sucrose

    NARCIS (Netherlands)

    van Ling, Gerrit; Driessen, Alfons J.; Piet, Arie C.; Vlugter, Jozef C.

    1970-01-01

    Several continuous reactor systems have been discussed for the catalytic high pressure hydrogenolysis of sucrose to glycerol. Theoretically and actually, continuous reactors lead to lower glycerol yields than in a batch process. Two continuous stirred tank reactors in cascade constitute a reasonable

  17. Effect of organic loading rate on dark fermentative hydrogen production in the continuous stirred tank reactor and continuous mixed immobilized sludge reactor from waste pastry hydrolysate.

    Science.gov (United States)

    Han, Wei; Hu, Yunyi; Li, Shiyi; Nie, Qiulin; Zhao, Hongting; Tang, Junhong

    2016-12-01

    Waste pastry (6%, w/v) was hydrolyzed by the produced glucoamylase and protease to obtain the glucose (19.8g/L) and free amino nitrogen (179mg/L) solution. Then, the effect of organic loading rate (OLR) (8-40kgCOD/(m 3 d)) on dark fermentative hydrogen production in the continuous stirred tank reactor (CSTR) and continuous mixed immobilized sludge reactor (CMISR) from waste pastry hydrolysate was investigated and compared. The maximum hydrogen production rate of CSTR (277.76mL/(hL)) and CMISR (320.2mL/(hL)) were achieved at OLR of 24kgCOD/(m 3 d) and 32kgCOD/(m 3 d), respectively. Carbon recovery ranged from 75.2-84.1% in the CSTR and CMISR with the balance assumed to be converted to biomass. One gram waste pastry could produce 0.33g (1.83mmol) glucose which could be further converted to 79.24mL (3.54mmol) hydrogen in the CMISR or 91.66mL (4.09mmol) hydrogen in the CSTR. This is the first study which reports dark fermentative hydrogen production from waste pastry. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Continuous cultivation of a thermophilic bacterium Aeribacillus pallidus 418 for production of an exopolysaccharide applicable in cosmetic creams.

    Science.gov (United States)

    Radchenkova, N; Panchev, I; Vassilev, S; Kuncheva, M; Dobreva, S; Kambourova, M

    2015-11-01

    The aim of this study was to evaluate the effectiveness of continuous cultivation approach for exopolysaccharide (EPS) production by a thermophilic micro-organism and the potential of the synthesized EPS for application in cosmetic industry. Study on the ability of Aeribacillus pallidus 418, isolated as a good EPS producer, to synthesize the polymer in continuous cultures showed higher production in comparison with batch cultures. The degree of the EPS in the precipitate after continuous cultivation significantly increased. Non-Newtonian pseudoplastic and thixotropic behaviour of EPS determines the ability of the received cream to become more fluid after increasing time of application on the skin. This study demonstrates a highly efficient way for production of EPS from a continuous growth culture of A. pallidus 418 that have many advantages and can outperform batch culture by eliminating time for cleaning and sterilization of the vessel and the comparatively long lag phases before the organisms enter a brief period of high productivity. The valuable physico-chemical properties of the synthesized EPS influenced positively the properties of a commercial cream. EPSs from thermophilic micro-organisms are of special interest due to the advantages of the thermophilic processes and nonpathogenic nature of the polymer molecules. However, their industrial application is hindered by the comparatively low biomass and correspondingly EPS yield. Suggested continuous approach for EPS could have an enormous economic potential for an industrial scale production of thermophilic EPSs. © 2015 The Society for Applied Microbiology.

  19. Prospective of biodiesel production utilizing microalgae as the cell ...

    African Journals Online (AJOL)

    Microalgae are sunlight-driven miniature factories that convert atmospheric CO2 to polar and neutral lipids which after esterification can be utilized as an alternative source of petroleum. Further, other metabolic products such as bioethanol and biohydrogen produced by algal cells are also being considered for the same ...

  20. Dose and time response of ruminally infused algae on rumen fermentation characteristics, biohydrogenation and Butyrivibrio group bacteria in goats.

    Science.gov (United States)

    Zhu, Honglong; Fievez, Veerle; Mao, Shengyong; He, Wenbo; Zhu, Weiyun

    2016-01-01

    Micro-algae could inhibit the complete rumen BH of dietary 18-carbon unsaturated fatty acid (UFAs). This study aimed to examine dose and time responses of algae supplementation on rumen fermentation, biohydrogenation and Butyrivibrio group bacteria in goats. Six goats were used in a repeated 3 × 3 Latin square design, and offered a fixed diet. Algae were infused through rumen cannule with 0 (Control), 6.1 (L-Alg), or 18.3 g (H-Alg) per day. Rumen contents were sampled on d 0, 3, 7, 14 and 20. H-Alg reduced total volatile fatty acid concentration and acetate molar proportion (P Algae induced a dose-dependent decrease in 18:0 and increased trans-18:1 in the ruminal content (P Algae had no effect on the abundances of Butyrivibrio spp. and Butyrivibrio proteoclasticus (P > 0.10), while H-Alg reduced the total bacteria abundance (P algae were related to the supplementation level, but there was no evidence of shift in ruminal biohydrogenation pathways towards t10-18:1. L-Alg mainly induced a transient effect on rumen biohydrogenation of 18-carbon UFAs, while H-Alg showed an acute inhibition and these effects were not associated with the known hydrogenating bacteria.

  1. Effect of organic loading rate on fermentative hydrogen production from continuous stirred tank and membrane bioreactors

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Lihong [Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, Ontario, M5S 1A4 (Canada); Bagley, David M. [Department of Civil and Architectural Engineering, Dept. 3295, University of Wyoming, 1000 E. University Ave., Laramie, WY 82071 (United States); Liss, Steven N. [Department of Environmental Biology, University of Guelph, 50 Stone Road, Guelph, Ontario, N1G 2W1 (Canada)

    2009-05-15

    The influence of organic loading rates (OLRs) on the performance of fermentative hydrogen-producing bioreactors operating in continuous stirred tank reactor (CSTR) and membrane bioreactor (MBR) modes was examined. Five OLRs were examined, ranging from 4.0 to 30 g COD L{sup -1} d{sup -1}, with influent glucose concentrations ranging from 1.3 to 10 g COD L{sup -1}. At OLRs up to 13 g COD L{sup -1} d{sup -1}, all influent glucose was utilized and the H{sub 2} yield was not significantly influenced by OLR, although the yield in the CSTR mode was significantly higher than that in the MBR mode, 1.25 versus 0.97 mol H{sub 2} (mol Gluc. Conv.){sup -1}, respectively. At an OLR of 30 g COD L{sup -1} d{sup -1}, both reactor modes were overloaded with respect to glucose utilization and also had significantly higher H{sub 2} yields of 1.77 and 1.49 mol H{sub 2} (mol Gluc. Conv.){sup -1} for the CSTR and MBR modes, respectively, versus the underloaded operation. At the intermediate OLR of 22 g COD L{sup -1} d{sup -1}, the H{sub 2} yield was maximized at 1.78 mol H{sub 2} (mol Gluc. Conv.){sup -1} for both the CSTR and MBR operation. Overall H{sub 2} production was 50% higher in the MBR mode, 0.78 versus 0.51 moles d{sup -1}, because the CSTR mode was overloaded with respect to glucose utilization at this OLR. These results suggest that an optimum OLR that maximizes H{sub 2} yield and H{sub 2} production may be near the OLR that causes overload with respect to substrate utilization. Additionally, while the CSTR mode is easier to operate and provides higher H{sub 2} yields at underloaded and overloaded OLRs, the MBR mode may be preferable when operating near the optimum OLR. (author)

  2. Continual monitoring of radon decay products concentration in indoor and outdoor air

    International Nuclear Information System (INIS)

    Petruf, P.; Holy, K.; Stanys, T.

    1998-01-01

    The goal of this work was the development of the method and construction and testing of measurement device for continual monitoring of radon daughters concentrations in the indoor and outdoor environment with regard to make possible to determine very low activities in the outdoor air (below % Bq/m 3 ). In this method air sample is drawn through the appropriate filter material. Radon and thoron daughters both attached and unattached on aerosols particles are collected on the filter surface and then the filter activity is counted. The silicon surface barrier detector with the active area of 200 mm 2 in monitor was used. The Millipore AW19-type filter was chosen and sampling rate of 30 l/min for collecting of the air samples. The determination of the individual activity concentrations in three-count method is based on the solution of the simultaneous equations describing the number of atoms of measured nuclides on the filter during and after sampling. The monitor was tested in three different environments (the average values of the activity concentrations of radon and its decay products in Bq/m 3 are given): in the basement of the building: 61.4 ± 5.0 of 222 Rn, 29.5 ± 2.8 of 218 Po, 14.1 ± 1.8 of 214 Pb and 12.1 ± 1.6 of 214 Bi; in the room on the second floor of the same building:22.2 ± 7.9 of 222 Rn, 7.3 ± 2.8 of 218 Po, 4.6 ± 1.9 of 214 Pb and 2.6 ± 1.2 of 214 Bi ; in the outdoor air in front of the building: 4.1 ± 2.7 of 222 Rn, 2.3 ± 0.9 of 218 Po, 1.5 ± 0.8 of 214 Pb and 1.4 ± 0.6 of 214 Bi. The results show a good agreement with expectations of the activity concentrations in three different environments. The monitor enables to determine low activity concentrations in the outdoor with an acceptable precision during one hour counting. The monitor can be used for the research of the correlation between the atmospheric stability and activity concentrations of radon decay products

  3. Large-Scale, Continuous-Flow Production of Stressed Biomass (Desulfovibrio vulgaris Hildenborough)

    Energy Technology Data Exchange (ETDEWEB)

    Geller, Jil T.; Borglin, Sharon E.; Fortney, Julian L.; Lam, Bonita R.; Hazen, Terry C.; Biggin, Mark D.

    2010-05-01

    The Protein Complex Analysis Project (PCAP, http://pcap.lbl.gov/), focuses on high-throughput analysis of microbial protein complexes in the anaerobic, sulfate-reducing organism, DesulfovibriovulgarisHildenborough(DvH).Interest in DvHas a model organism for bioremediation of contaminated groundwater sites arises from its ability to reduce heavy metals. D. vulgarishas been isolated from contaminated groundwater of sites in the DOE complex. To understand the effect of environmental changes on the organism, midlog-phase cultures are exposed to nitrate and salt stresses (at the minimum inhibitory concentration, which reduces growth rates by 50percent), and compared to controls of cultures at midlogand stationary phases. Large volumes of culture of consistent quality (up to 100 liters) are needed because of the relatively low cell density of DvHcultures (one order of magnitude lower than E. coli, for example) and PCAP's challenge to characterize low-abundance membrane proteins. Cultures are grown in continuous flow stirred tank reactors (CFSTRs) to produce consistent cell densities. Stressor is added to the outflow from the CFSTR, and the mixture is pumped through a plug flow reactor (PFR), to provide a stress exposure time of 2 hours. Effluent is chilled and held in large carboys until it is centrifuged. A variety of analyses -- including metabolites, total proteins, cell density and phospholipidfatty-acids -- track culture consistency within a production run, and differences due to stress exposure and growth phase for the different conditions used. With our system we are able to produce the requisite 100 L of culture for a given condition within a week.

  4. The influence of nitrogen sources on the alpha-amylase productivity of Aspergillus oryzae in continuous cultures

    DEFF Research Database (Denmark)

    Pedersen, Henrik; Nielsen, Jens

    2000-01-01

    The influence of the nitrogen source on the cc-amylase productivity of Aspergillus oryzae was quantified in continuous cultivations. Both inorganic and complex nitrogen sources were investigated and glucose was used as the carbon and energy sources. For production of alpha-amylase, nitrate...... in the cc-amylase productivity. The higher alpha-amylase productivity during growth on casein hydrolysate was not caused by increased transcription of the alpha-amylase genes but was caused by a faster secretion of alpha-amylase or by a lower binding of alpha-amylase to the biomass....

  5. Extension of $b{sub f}$-continuous functions defined on a product of $b{sub f}$-groups

    Energy Technology Data Exchange (ETDEWEB)

    Sanchis, M.

    2017-07-01

    Let X be a bf -space and let G be a bf -group. By means of the exponential mapping we characterize when a bf -continuous function on X × G with values in a topologically complete sapce Z has a bf -continuous extension to β(X) × G. As a consequence we show that the product of a pseudocompact space and a bf -group is a bf -group. This result generalizes the fact that the product of a pseudocompact space and a pseudocompact group is pseudocompact. (Author)

  6. Hydrolysis of a mixture of saccharides by cellulase from Aspergillus niger and its application for visible-light-induced hydrogen gas production system using Mg chlorophyll-a and platinum nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Amao, Yutaka; Hirakawa, Takamasa [Department of Applied Chemistry, Oita University, Dannoharu 700, Oita 870-1192 (Japan)

    2010-07-15

    Cellulase obtained from Aspergillus niger was used to hydrolyze a mixture of saccharides containing sucrose, maltose, and cellobiose; the reduced form of nicotinamide-adenine dinucleotide (NAD{sup +}), which is NADH, was produced during hydrolysis of the mixture of saccharides in the presence of NAD{sup +} and glucose dehydrogenase (GDH). We have developed a visible-light-induced enzymatic biohydrogen production system involving the combination of cellulase-mediated hydrolysis of the mixture of saccharides and hydrogen production by platinum nanoparticles using photosensitization of Mg chlorophyll-a (Mg Chl-a). Continuous production of hydrogen gas was observed when the reaction mixture containing saccharides, cellulase, GDH, NAD{sup +}, Mg Chl-a, methylviologen (MV{sup 2+}, an electron donor), and platinum nanoparticles was irradiated by visible light. After 120 min of irradiation, the amount of hydrogen produced from the mixture of saccharides was approximately 2.8 {mu}mol. (author)

  7. Evaluation of Packed-Bed Reactor and Continuous Stirred Tank Reactor for the Production of Colchicine Derivatives

    OpenAIRE

    Dubey, Kashyap Kumar; Kumar, Dhirendra; Kumar, Punit; Haque, Shafiul; Jawed, Arshad

    2013-01-01

    Bioconversion of colchicine into its pharmacologically active derivative 3-demethylated colchicine (3-DMC) mediated by P450BM3 enzyme is an economic and promising strategy for the production of this inexpensive and potent anticancer drug. Continuous stirred tank reactor (CSTR) and packed-bed reactor (PBR) of 3 L and 2 L total volumes were compared for the production of 3-demethylated colchicine (3-DMC) a colchicine derivative using Bacillus megaterium MTCC*420 under aerobic conditions. Statis...

  8. Real time continuous oxygen concentration monitoring system during malaxation for the production of Virgin Olive Oil

    Directory of Open Access Journals (Sweden)

    Aiello, G.

    2012-10-01

    Full Text Available During the mechanical extraction process of Virgin Olive Oil (VOO some important physical phenomena and enzymatic transformations occur which influence the quality of the final product. The control of process parameters is crucial to ensure the quality of VOO, therefore process monitoring and control is a fundamental requirement in the modern VOO processing industry. The present work proposes an innovative Real-Time Monitoring System (RTMS aimed at continuously measuring the oxygen concentration during the malaxation process in order to establish a correlation with the quality of the final product obtained. This monitoring system is based on an oxygen concentration sensor directly connected to the malaxation chamber and a data acquisition system to analyze and store the measured values in a process database. The experimental results obtained show that the use of oxygen during malaxation improves some qualitative parameters of VOO such as free fatty acids and total polyphenols while others (peroxide values and spectrophotometric indexes worsen. These results are similar to those obtained by employing nitrogen, which is the traditional technique to avoid the wellknown oxidation processes studied by several researchers, thus demonstrating that the presence of oxygen during the malaxation process can have beneficial effects on the quality of VOO when its concentration is properly controlled.

    Durante el proceso de extracción mecánica del aceite de oliva virgen ocurren importantes fenómenos físicos y transformaciones enzimáticas que influyen en la calidad del producto final. El control de los parámetros del proceso es crucial para garantizar la calidad del aceite de oliva virgen, por tanto la monitorización y el control del proceso son requisitos fundamentales en el moderno tratamiento industrial del aceite de oliva virgen. El presente trabajo propone un sistema de monitorización innovador en tiempo real dirigido a medir continuamente

  9. Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ.

    Science.gov (United States)

    Pashaei, S; Ghoorchi, T; Yamchi, A

    2016-04-01

    An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro-organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

  10. Product sampling during transient continuous countercurrent hydrolysis of canola oil and development of a kinetic model

    KAUST Repository

    Wang, Weicheng; Natelson, Robert H.; Stikeleather, Larry F.; Roberts, William L.

    2013-01-01

    A chemical kinetic model has been developed for the transient stage of the continuous countercurrent hydrolysis of triglycerides to free fatty acids and glycerol. Departure functions and group contribution methods were applied to determine

  11. Accuracy assessment of the vegetation continuous field tree cover product using 3954 ground plots in the southwestern USA

    Science.gov (United States)

    M. A. White; J. D. Shaw; R. D. Ramsey

    2005-01-01

    An accuracy assessment of the Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation continuous field (VCF) tree cover product using two independent ground-based tree cover databases was conducted. Ground data included 1176 Forest Inventory and Analysis (FIA) plots for Arizona and 2778 Southwest Regional GAP (SWReGAP) plots for Utah and western Colorado....

  12. 40 CFR Table 12 to Subpart Xxxx of... - Continuous Compliance With the Emission Limits for Tire Cord Production Affected Sources

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Continuous Compliance With the Emission Limits for Tire Cord Production Affected Sources 12 Table 12 to Subpart XXXX of Part 63 Protection of... Pollutants: Rubber Tire Manufacturing Pt. 63, Subpt. XXXX, Table 12 Table 12 to Subpart XXXX of Part 63...

  13. 40 CFR Table 10 to Subpart Xxxx of... - Continuous Compliance With the Emission Limits for Tire Production Affected Sources

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Continuous Compliance With the Emission Limits for Tire Production Affected Sources 10 Table 10 to Subpart XXXX of Part 63 Protection of... Pollutants: Rubber Tire Manufacturing Pt. 63, Subpt. XXXX, Table 10 Table 10 to Subpart XXXX of Part 63...

  14. Continuous fermentation and in-situ reed separation of butyric acid for higher sugar consumption rate and productivity

    DEFF Research Database (Denmark)

    Baroi, George Nabin; Skiadas, Ioannis; Westermann, Peter

    that disconnection of the REED system resulted to much lower (48 and 83% for glucose and xylose, respectively) sugars consumption rates and consequently lower butyric acid production rates. It was also noticeable that continuous operation, even without the REED system, resulted to higher glucose consumption rates...

  15. Continuous usage of a hair dye product containing 2-methoxymethyt-para-phenylenediamine by hair-dye-allergic individuals

    NARCIS (Netherlands)

    Kock, M.; Coenraads, P. -J.; Bloemeke, B.; Goebel, C.

    Background Despite a positive patch test reaction to para-phenylenediamine (PPD) and/or toluene-2,5-diamine (PTD), many people attempt to continue dyeing their hair with products containing PPD or its derivatives. Objectives Investigation of elicitation reactions among PPD/PTD-allergic individuals

  16. Active pharmaceutical ingredient (API) production involving continuous processes – A process system engineering (PSE)-assisted design framework

    DEFF Research Database (Denmark)

    Cervera Padrell, Albert Emili; Skovby, Tommy; Kiil, Søren

    2012-01-01

    and fermentation-based products. The method exploits the synergic combination of continuous flow technologies (e.g., microfluidic techniques) and process systems engineering (PSE) methods and tools for faster process design and increased process understanding throughout the whole drug product and process...... kg of product – was reduced to half of its initial value, with potential for further reduction. The case-study includes reaction steps typically used by the pharmaceutical industry featuring different characteristic reaction times, as well as L–L separation and distillation-based solvent exchange...

  17. Continuous hydrogen and methane production from Agave tequilana bagasse hydrolysate by sequential process to maximize energy recovery efficiency.

    Science.gov (United States)

    Montiel Corona, Virginia; Razo-Flores, Elías

    2018-02-01

    Continuous H 2 and CH 4 production in a two-stage process to increase energy recovery from agave bagasse enzymatic-hydrolysate was studied. In the first stage, the effect of organic loading rate (OLR) and stirring speed on volumetric hydrogen production rate (VHPR) was evaluated in a continuous stirred tank reactor (CSTR); by controlling the homoacetogenesis with the agitation speed and maintaining an OLR of 44 g COD/L-d, it was possible to reach a VHPR of 6 L H 2 /L-d, equivalent to 1.34 kJ/g bagasse. In the second stage, the effluent from CSTR was used as substrate to feed a UASB reactor for CH 4 production. Volumetric methane production rate (VMPR) of 6.4 L CH 4 /L-d was achieved with a high OLR (20 g COD/L-d) and short hydraulic retention time (HRT, 14 h), producing 225 mL CH 4 /g-bagasse equivalent to 7.88 kJ/g bagasse. The two-stage continuous process significantly increased energy conversion efficiency (56%) compared to one-stage hydrogen production (8.2%). Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. 75 FR 26919 - Certain Crepe Paper Products From the People's Republic of China: Continuation of Antidumping...

    Science.gov (United States)

    2010-05-13

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-570-895] Certain Crepe Paper Products... International Trade Commission (``ITC'') that revocation of the antidumping duty order on certain crepe paper... duty order on certain crepe paper products from the PRC pursuant to section 751(c) of the Tariff Act of...

  19. On the random cascading model study of anomalous scaling in multiparticle production with continuously diminishing scale

    International Nuclear Information System (INIS)

    Liu Lianshou; Zhang Yang; Wu Yuanfang

    1996-01-01

    The anomalous scaling of factorial moments with continuously diminishing scale is studied using a random cascading model. It is shown that the model currently used have the property of anomalous scaling only for descrete values of elementary cell size. A revised model is proposed which can give good scaling property also for continuously varying scale. It turns out that the strip integral has good scaling property provided the integral regions are chosen correctly, and that this property is insensitive to the concrete way of self-similar subdivision of phase space in the models. (orig.)

  20. Continuous production of fullerenes and other carbon nanomaterials on a semi-industrial scale using plasma technology

    International Nuclear Information System (INIS)

    Gruenberger, T.M.; Gonzalez-Aguilar, J.; Fulcheri, L.; Fabry, F.; Grivei, E.; Probst, N.; Flamant, G.; Charlier, J.-C.

    2002-01-01

    A new production method is presented allowing the production of bulk quantities of fullerenes and other carbon nanomaterials using a 3-phase thermal plasma (260 kW). The main characteristics of this method lie in the independent control of the carbon throughput by injection of a solid carbon feedstock, and the immediate extraction of the synthesised product from the reactor, allowing production on a continuous basis. The currently investigated plasma facility is of an intermediate scale between lab-size and an industrial pilot plant, ready for further up scaling to an industrial size. The influence of a large number of different carbon precursors, plasma gases and operating conditions on the fullerene yield has been studied. At this state, quantities of up to 1 kg of carbon can be processed per hour with further scope for increase, leading to production rates for this type of materials not achievable with any other technology at present

  1. Continuous wet oxidation pretreatment of lignocellulosic biomass with subsequent continuous ethanol production; Kontinuerlig vaadoxidationsforbehandling af lignocelluloseholdige biomasser med efterfoelgende kontinuerlig ethanolfremstilling

    Energy Technology Data Exchange (ETDEWEB)

    Ahring, B.K.; Torry-Smith, M.; Loeth, A.H.

    2001-07-01

    In this project the possibility of implementing a UASB-reactor for detoxification of the recirculation water is investigated. Bioethanol- effluent (BEE) made from wet-oxidized wheat straw (60 g-wheat straw/l-water) fermented with Saccharomyces cerevisiae and Thermoanaerobacter mathranii A3M4 is in this project used to simulate the effluent from a commercial bioethanol plant. To investigate the gas potential and conversion of inhibitors, BEE is investigated both in batch and in a laboratory scale UASB reactor. In batch tests the conversion of acetovanillon, 2-furan acid and 4-hydroxyacetophenon was investigated with the substances themselves, as single substrat, and by co-digestion with BEE. The experiments show that the conversion of the three substances together with BEE had a positive influence on the decomposition and the inhibition levels. Tests with conversion of BEE in a laboratory scale UASB-reactor showed that by loading up to 29 g-COD/l it was possible to obtain a COD-reduction at 80% (w/w). At the same time GC-analyses of vanillin acid, homo vanillin acid, aceton vanillon, syringon acid, acetosyringon, syringol, 4-hydroxybenzo acid, 4-hydroxbenzaldenhyde, 2-furan acid, and phenol showed that all these substances were converted in the UASB-reactor. Economical calculations carried out on the basis of the results from the experiments indicate that the implementation of a UASB-cleaning step for cleaning the bioethanol process water can be carried out with a economical profit, which among other means a short payback time on the investment. It is things concluded that the implementation of a UASB-cleaning step is a qualified method to detoxify process water for bioethanol production and thereby reduce the total production costs of the commercial bioethanol production based on lignocelluslose materials. The necessity of tests with repeated recirculations are indicated, because continuous reuse of the process water can result in up-concentration of any inhibitors

  2. Digital decoration by continuous ink jet system for ceramic products based in water inks

    International Nuclear Information System (INIS)

    Colores Ceramicos, S. A.; Talleres Foro, S. L.

    2010-01-01

    A new continuous ink jet system for digital ceramic decoration using water based dispersed ceramic pigment has been developed, that increases drastically the sustainability of the process. During the development of this work, different equipment for any application and the consumables and design tools have been also developed. (Author)

  3. Optimisation of Lab-Scale Continuous Alcohol-Free Beer Production

    Czech Academy of Sciences Publication Activity Database

    Lehnert, R.; Novák, Pavel; Macieira, F.; Kuřec, M.; Teixeira, J.A.; Brányik, T.

    2009-01-01

    Roč. 27, č. 4 (2009), s. 267-275 ISSN 1212-1800 Institutional research plan: CEZ:AV0Z40720504 Keywords : alcohol-free beer * continuous reactor * immobilised yeast Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.602, year: 2009

  4. Heat transfer and the continuous production of hydroxypropyl starch in a static mixer reactor

    NARCIS (Netherlands)

    Lammers, Gerard; Beenackers, Antonie A. C. M.

    1994-01-01

    A novel continuous reactor for the chemical derivation of aqueous starch solutions based on static mixers is proposed. Both the experimentally observed axial and radial temperature gradients in the static mixer could be accurately described by a pseudohomogeneous two-dimensional heat transfer (PTHT)

  5. Continuous wasteless ecologically safe technology of propylenecarbonate production in presence of phthalocyanine catalysts

    Science.gov (United States)

    Afanasiev, Vladimir Vasilievich [Moscow, RU; Zefirov, Nikolai Serafimovich [Moscow, RU; Zalepugin, Dmitry Yurievich [Moscow, RU; Polyakov, Victor Stanislavovich [Moscow, RU; Tilkunova, Nataliya Alexandrovna [Moscow, RU; Tomilova, Larisa Godvigovna [Moscow, RU

    2009-09-08

    A continuous method of producing propylenecarbonate includes carboxylation of propylene oxide with carbon dioxide in presence of phthalocyanine catalyst on an inert carrier, using as the phthalocyanine catalyst at least one catalyst selected from the group consisting of not-substituted, methyl, ethyl, butyl, and tret butyl-substituted phthalocyanines of metals, including those containing counterions, and using as the carrier a hydrophobic carrier.

  6. Butanol production by bioconversion of cheese whey in a continuous packed bed reactor.

    Science.gov (United States)

    Raganati, F; Olivieri, G; Procentese, A; Russo, M E; Salatino, P; Marzocchella, A

    2013-06-01

    Butanol production by Clostridium acetobutylicum DSM 792 fermentation was investigated. Unsupplemented cheese whey was adopted as renewable feedstock. The conversion was successfully carried out in a biofilm packed bed reactor (PBR) for more than 3 months. The PBR was a 4 cm ID, 16 cm high glass tube with a 8 cm bed of 3mm Tygon rings, as carriers. It was operated at the dilution rate between 0.4h(-1) and 0.94 h(-1). The cheese whey conversion process was characterized in terms of metabolites production (butanol included), lactose conversion and biofilm mass. Under optimized conditions, the performances were: butanol productivity 2.66 g/Lh, butanol concentration 4.93 g/L, butanol yield 0.26 g/g, butanol selectivity of the overall solvents production 82 wt%. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. EXPERIMENT ON LONG-STORAGE OF FOOD PRODUCTS FOODSTUFFS IN CODITION OF PERMAFROST CONTINUED, ARCTIC, 2016

    Directory of Open Access Journals (Sweden)

    S. E. Ulanin

    2016-01-01

    Full Text Available In 1973 the crew of polar expedition, investigating the Middendorff Bay at the messdeck Zarya, discovered the depot of food products hidden in permafrost by head of Russian polar expedition E. Toll in 1900. There were oat flakes ‘Gerkules’ and croutons in the depot. Then the study carried out in Research Institute of Vegetable Drying and Can Industry had shown that all products discovered had preserved all their food qualities. That result leaded to launch up the experimental work on the possibility of preservation of food products and foodstuffs in permafrost till 2050. Quality of product found out in Taymyr Peninsula was analyzed. The results of study on qualities after long preservation in permafrost of such food products and foodstuffs as meat, milk, fish, confectionery, concentrated food, plant seeds were given. As a result of expedition in 2016, 20 samples were taken out and new samples of two types of products were placed into repository. Overall products placed consisted of 23 items, including foodstuffs and plant seeds with account of taking them out in 2025, 2035 and 2050. On the basis of research carried out, it is proved that most of modern and casual food products can be preserved without losing their quality values.

  8. Enabling continuous-flow chemistry in microstructured devices for pharmaceutical and fine-chemical production.

    Science.gov (United States)

    Kockmann, Norbert; Gottsponer, Michael; Zimmermann, Bertin; Roberge, Dominique M

    2008-01-01

    Microstructured devices offer unique transport capabilities for rapid mixing, enhanced heat and mass transfer and can handle small amounts of dangerous or unstable materials. The integration of reaction kinetics into fluid dynamics and transport phenomena is essential for successful application from process design in laboratory to chemical production. Strategies to implement production campaigns up to tons of pharmaceutical chemicals are discussed, based on Lonza projects.

  9. Development of an advanced, continuous mild gasification process for the production of co-products: Topical report

    Energy Technology Data Exchange (ETDEWEB)

    Cha, C.Y.; Merriam, N.W.; Jha, M.C.; Breault, R.W.

    1988-06-01

    Research on mild gasification is discussed. The report is divided into three sections: literature survey of mild gasification processes; literature survey of char, condensibles, and gas upgrading and utilization methods; and industrial market assessment of products of mild gasification. Recommendations are included in each section. (CBS) 248 refs., 58 figs., 62 tabs.

  10. Improving EGSB reactor performance for simultaneous bioenergy and organic acid production from cheese whey via continuous biological H2 production.

    Science.gov (United States)

    Ramos, Lucas Rodrigues; Silva, Edson Luiz

    2017-07-01

    To evaluate the influence of hydraulic retention time (HRT) and cheese whey (CW) substrate concentration (15 and 25 g lactose l -1 ) on the performance of EGSB reactors (R15 and R25, respectively) for H 2 production. A decrease in the HRT from 8 to 4 h favored the H 2 yield and H 2 production rate (HPR) in R15, with maximum values of 0.86 ± 0.11 mmol H 2 g COD -1 and 0.23 ± 0.024 l H 2 h -1 l -1 , respectively. H 2 production in R25 was also favored at a HRT of 4 h, with maximum yield and HPR values of 0.64 ± 0.023 mmol H 2 g COD -1 and 0.31 ± 0.032 l H 2 h -1 l -1 , respectively. The main metabolites produced were butyric, acetic and lactic acids. The EGSB reactor was evaluated as a viable acidogenic step in the two-stage anaerobic treatment of CW for the increase of COD removal efficiency and biomethane production.

  11. Product sampling during transient continuous countercurrent hydrolysis of canola oil and development of a kinetic model

    KAUST Repository

    Wang, Weicheng

    2013-11-01

    A chemical kinetic model has been developed for the transient stage of the continuous countercurrent hydrolysis of triglycerides to free fatty acids and glycerol. Departure functions and group contribution methods were applied to determine the equilibrium constants of the four reversible reactions in the kinetic model. Continuous countercurrent hydrolysis of canola oil in subcritical water was conducted experimentally in a lab-scale reactor over a range of temperatures and the concentrations of all neutral components were quantified. Several of the rate constants in the model were obtained by modeling this experimental data, with the remaining determined from calculated equilibrium constants. Some reactions not included in the present, or previous, hydrolysis modeling efforts were identified from glycerolysis kinetic studies and may explain the slight discrepancy between model and experiment. The rate constants determined in this paper indicate that diglycerides in the feedstock accelerate the transition from "emulsive hydrolysis" to "rapid hydrolysis". © 2013 Elsevier Ltd.

  12. Development of an advanced, continuous mild gasification process for the production of co-products (Task 1), Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Knight, R.A.; Gissy, J.L.; Onischak, M.; Babu, S.P.; Carty, R.H. (Institute of Gas Technology, Chicago, IL (United States)); Duthie, R.G. (Bechtel Group, Inc., San Francisco, CA (United States)); Wootten, J.M. (Peabody Holding Co., Inc., St. Louis, MO (United States))

    1991-09-01

    Under US DOE sponsorship, a project team consisting of the Institute of Gas Technology, Peabody Holding Company, and Bechtel Group, Inc. has been developing an advanced, mild gasification process to process all types of coal and to produce solid and condensable liquid co-products that can open new markets for coal. The three and a half year program (September 1987 to June 1991) consisted of investigations in four main areas. These areas are: (1) Literature Survey of Mild Gasification Processes, Co-Product Upgrading and Utilization, and Market Assessment; (2) Mild Gasification Technology Development: Process Research Unit Tests Using Slipstream Sampling; (3) Bench-Scale Char Upgrading Study; (4) Mild Gasification Technology Development: System Integration Studies. In this report, the literature and market assessment of mild gasification processes are discussed.

  13. Improved glycerol production from cane molasses by the sulfite process with vacuum or continuous carbon dioxide sparging during fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Kalle, G.P.; Naik, S.C.; Lashkari, B.Z.

    1985-01-01

    The conventional sulfite process for glycerol production from molasses using Saccharomyces cerevisiae var. Hansen was modified to obtain product concentrations of up to 230 g/l and productivity of 15 g/l.d by fermenting under vacuum (80 mm) or with continuous sparging of CO2 (0.4 vvm). Under these conditions the requirement of sulfite for optimum production of glycerol was reduced by two thirds (20 g/l), the ethanol concentration in the medium was kept below 30 g/l and the competence of yeast cells to ferment was conserved throughout the fermentation period for up to 20 days. In addition to the above, the rate of incorporation of sulfite had a significant effect on glucose fermentation and glycerol yields. There was an optimal relationship between glycerol yields and the molar ratio of sulfite to glucose consumed, which for cane molasses was 0.67. This ratio was characteristic of the medium composition.

  14. Comparative study of production of Bio-Indigo by Pandoraea sp. in a two phase - fed batch and continuous bioreactor

    Directory of Open Access Journals (Sweden)

    Vaishnavi Unde

    2016-03-01

    Full Text Available Indigo, is blue of blue jeans, a synthetic dye used on large scale all over the world. Chemical production of the dye is taking a new route towards bacterial production to overcome the environmental effects that are posed by the synthetic blue powder (Indigo. In the present work a strain Pandoraea sp. isolated from the oil contaminated soil is found to produce blue pigment which is analyzed qualitatively as indigo using UV-visible scan and Thin Layer Chromatography (TLC. The strain is used for indigo production at lab scale in two different bioreactor configurations first the fed batch mode and second continuous mode using two phases. The two phases consisting of medium carrying biomass and the second phase of silicone oil carrying substrate indole. The use of second phase allows higher concentration of substrate injection reducing the inhibition effects of the substrate as well as act as a partitioning agent for removal of the product. In two phase study, the maximum indigo produced was seen to be 0.068 g/L after 22 hours of substrate injection into the Fermentor in a fed batch mode. The maximum yield obtained in this configuration was 19%. For commercial production of bio-indigo a continuous operation is required, which was studied in a bioreactor with 2.5 liter capacity under the optimized conditions. The maximum indigo produced was found to be 0.052 g/L after about 72 hours of operation. The results showed decrease in the production of indigo in continuous mode as compared to fed batch operation, which may be due to the insufficient time available for the bacteria to bio-transform indole into indigo.

  15. Sustainable MSD prevention: management for continuous improvement between prevention and production. Ergonomic intervention in two assembly line companies.

    Science.gov (United States)

    Caroly, S; Coutarel, F; Landry, A; Mary-Cheray, I

    2010-07-01

    To increase output and meet customers' needs, companies have turned to the development of production management systems: Kaizen, one piece flow, Kanban, etc. The aim of such systems is to accelerate decisions, react to environmental issues and manage various productions. In the main, this type of management system has led to the continuous improvement of production performance. Consequently, such production management systems can have unexpected negative effects on operators' health and safety. Conversely, regulation and control systems focusing on work-related risks have obliged firms to implement health and safety management systems such as OHSAS 18001. The purpose of this type of system, also based on continuous improvement, is to reduce risks, facilitate work-related activities and identify solutions in terms of equipment and tools. However, the prevention actions introduced through health and safety systems often result in other unexpected and unwanted effects on production. This paper shows how companies can improve the way they are run by taking into account both types of management system. Copyright 2010 Elsevier Ltd. All rights reserved.

  16. Growth and lipid accumulation characteristics of Scenedesmus obliquus in semi-continuous cultivation outdoors for biodiesel feedstock production.

    Science.gov (United States)

    Feng, Pingzhong; Yang, Kang; Xu, Zhongbin; Wang, Zhongming; Fan, Lu; Qin, Lei; Zhu, Shunni; Shang, Changhua; Chai, Peng; Yuan, Zhenhong; Hu, Lei

    2014-12-01

    In an effort to identify suitable microalgal species for biodiesel production, seven species were isolated from various habitats and their growth characteristics were compared. The results demonstrated that a green alga Scenedesmus obliquus could grow more rapidly and synthesize more lipids than other six microalgal strains. S. obliquus grew well both indoors and outdoors, and reached higher μmax indoors than that outdoors. However, the cells achieved higher dry weight (4.36 g L(-1)), lipid content (49.6%) and productivity (183 mg L(-1) day(-1)) outdoors than in indoor cultures. During the 61 days semi-continuous cultivation outdoors, high biomass productivities (450-550 mg L(-1) day(-1)) and μmax (1.05-1.44 day(-1)) were obtained. The cells could also achieve high lipid productivities (151-193 mg L(-1) day(-1)). These results indicated that S. obliquus was promising for lipids production in semi-continuous cultivation outdoors. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Development of a continuous process for adjusting nitrate, zirconium, and free hydrofluoric acid concentrations in zirconium fuel dissolver product

    International Nuclear Information System (INIS)

    Cresap, D.A.; Halverson, D.S.

    1993-04-01

    In the Fluorinel Dissolution Process (FDP) upgrade, excess hydrofluoric acid in the dissolver product must be complexed with aluminum nitrate (ANN) to eliminate corrosion concerns, adjusted with nitrate to facilitate extraction, and diluted with water to ensure solution stability. This is currently accomplished via batch processing in large vessels. However, to accommodate increases in projected throughput and reduce water production in a cost-effective manner, a semi-continuous system (In-line Complexing (ILC)) has been developed. The major conclusions drawn from tests demonstrating the feasibility of this concept are given in this report

  18. Safety considerations for continuous hydrogen production test apparatus with capacity of 50 N-litter hydrogen per hour

    International Nuclear Information System (INIS)

    Onuki, Kaoru; Akino, Norio; Shimizu, Saburo; Nakajima, Hayato; Higashi, Shunichi; Kubo, Shinji

    2001-03-01

    Since the thermochemical hydrogen production Iodine-Sulfur process decomposes water into hydrogen and oxygen using toxic chemicals such as sulfuric acid, iodine and hydriodic acid, safety considerations are very important in its research and development. Therefore, before construction of continuous hydrogen production test apparatus with capacity of 50 N-litter hydrogen per hour, comprehensive safety considerations were carried out to examine the design and construction works of the test apparatus, and the experimental plans using the apparatus. Emphasis was given on the safety considerations on prevention of breakage of glasswares and presumable abnormalities, accidents and their countermeasures. This report summarizes the results of the considerations. (author)

  19. Development of Food Functions and Production Process for Onion Vinegar Using a Two-Stage Continuous-Tank Reactor

    OpenAIRE

    小林, 秀彰; 山口, 文; 富田, 弘毅; 中井, 義昭; 管野, 亨; 小林, 正義; KOBAYASHI, Hideaki; YAMAGUCHI, Kazaru; TOMITA, Koki; NAKAI, Yoshiaki; KANNO, Tohru; KOBAYASHI, Masayoshi

    1998-01-01

    A two-stage continuous-tank reactor was developed to optimize the production of onion vinegar, and the onion vinegar produced was studied to determine its benefits for human health. The ”Silan ring” porous ceramics support was available to immobilize microorganisms, maintain higher mechanical strength and provide a stable rate of alcohol production even at higher dilution rates than 1.2 hr^, without wash-out. The forced cyclic operation of reaction temperature yielded an increase of 25% for ...

  20. Experimental continuous sludge microwave system to enhance dehydration ability and hydrogen production from anaerobic digestion of sludge.

    Science.gov (United States)

    Zhou, Cuihong; Huang, Xintong; Zeng, Meng

    2018-05-01

    Dehydrating large amounts of sludge produced by sewage treatment plants is difficult. Microwave pretreatment can effectively and significantly improve the dewaterability and hydrogen production of sludge subjected to anaerobic digestion. The aim of this study was to investigate the effects of different microwave conditions on hydrogen production from anaerobic digestion and dewaterability of sludge. Based on an analysis of the electric field distribution, a spiral reactor was designed and a continuous microwave system was built to conduct intermittent and continuous experiments under different conditions. Settling Volume, Capillary Suction Time, particle size, and moisture content of the sludge were measured. The results show that sludge pretreatment in continuous experiments has equally remarkable dehydration performance as in intermittent experiments; the minimum moisture content was 77.29% in the intermittent experiment under a microwave power of 300W and an exposure time of 60sec, and that in the continuous experiment was 77.56% under a microwave power of 400W and an exposure time of 60sec. The peak measured by Differential Scanning Calorimeter appeared earliest under a microwave power of 600W and an exposure time of 180sec. The heat flux at the peak was 4.343W/g, which is relatively small. This indicates that microwave pretreatment induced desirable effects. The maximum yield of hydrogen production was 7.967% under the conditions of microwave power of 500W, exposure time of 120sec, and water bath at 55°C. This research provides a theoretical and experimental basis for the development of a continuous microwave sludge-conditioning system. Copyright © 2017. Published by Elsevier B.V.

  1. Biohydrogen production from sugar rich substrates using the dark fermentation process

    DEFF Research Database (Denmark)

    Kongjan, Prawit

    Hydrogen og metan produceret ved mikrobiel omdannelse af organisk affald/restprodukter er et miljøvenligt og bæredygtigt alternativ til fossile brændstoffer. Hydrolysat rigt på xylose er et flydende biprodukt, der dannes under hydrotermisk forbehandling af plantematerialet lignocellulose. Produkt...

  2. Enhanced biohydrogen production from corn stover by the combination of Clostridium cellulolyticum and hydrogen fermentation bacteria.

    Science.gov (United States)

    Zhang, Shou-Chi; Lai, Qi-Heng; Lu, Yuan; Liu, Zhi-Dan; Wang, Tian-Min; Zhang, Chong; Xing, Xin-Hui

    2016-10-01

    Hydrogen was produced from steam-exploded corn stover by using a combination of the cellulolytic bacterium Clostridium cellulolyticum and non-cellulolytic hydrogen-producing bacteria. The highest hydrogen yield of the co-culture system with C. cellulolyticum and Citrobacter amalonaticus reached 51.9 L H2/kg total solid (TS). The metabolites from the co-culture system were significantly different from those of the mono-culture systems. Formate, which inhibits the growth of C. cellulolyticum, could be consumed by the hydrogen-evolving bacteria, and transformed into hydrogen. Glucose and xylose were released from corn stover via hydrolysis by C. cellulolyticum and were quickly utilized in dark fermentation with the co-cultured hydrogen-producing bacteria. Because the hydrolysis of corn stover by C. cellulolyticum was much slower than the utilization of glucose and xylose by the hydrogen-evolving bacteria, the sugar concentrations were always maintained at low levels, which favored a high hydrogen molar yield. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  3. Bio-methane & Bio-hydrogen. Status and perspectives of biological methane and hydrogen production

    NARCIS (Netherlands)

    Wijffels, R.H.; Janssen, M.G.J.

    2003-01-01

    Eerst wordt het kader geschetst voor de potentiële rol van bio-methaan en bio-waterstof in de energiehuishouding en de invloeden daarop van de ontwikkeling van eindgebruikstechnologie en infrastructuur, en het energiebeleid. Daarna wordt uitvoerig ingegaan op de technieken voor bio-methaan en

  4. Evaluation of tritium production rate in a gas-cooled reactor with continuous tritium recovery system for fusion reactors

    Energy Technology Data Exchange (ETDEWEB)

    Matsuura, Hideaki, E-mail: mat@nucl.kyushu-u.ac.jp [Department of Applied Quantum Physics and Nuclear Engineering, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan); Nakaya, Hiroyuki; Nakao, Yasuyuki [Department of Applied Quantum Physics and Nuclear Engineering, Kyushu University, 744 Motooka, Fukuoka 819-0395 (Japan); Shimakawa, Satoshi; Goto, Minoru; Nakagawa, Shigeaki [Japan Atomic Energy Agency, 4002 Oarai, Ibaraki 311-1393 (Japan); Nishikawa, Masabumi [Graduate School of Engineering Science, Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581 (Japan)

    2013-10-15

    Highlights: • The performance of a gas-cooled reactor as a tritium production system was studied. • A continuous tritium recovery using helium gas was considered. • Gas-cooled reactors with 3 GW output in all can produce ∼6 kg of tritium in a year • Performance of the system was examined for Li{sub 4}SiO{sub 4}, Li{sub 2}TiO{sub 3} and LiAlO{sub 2} compounds. -- Abstract: The performance of a high-temperature gas-cooled reactor as a tritium production with continuous tritium recovery system is examined. A gas turbine high-temperature reactor of 300-MWe (600 MW) nominal capacity (GTHTR300) is assumed as the calculation target, and using the continuous-energy Monte Carlo transport code MVP-BURN, burn-up simulations for the three-dimensional entire-core region of the GTHTR300 were performed. A Li loading pattern for the continuous tritium recovery system in the gas-cooled reactor is presented. It is shown that module gas-cooled reactors with a total thermal output power of 3 GW in all can produce ∼6 kg of tritium maximum in a year.

  5. Investigation of production of continuous off axis fibre reinforced thermoplastic material

    Science.gov (United States)

    McDonald, Philip C.

    Fibre reinforced composites have been used in the engineering industry for many years since the discovery of glass fibre in 1930 and its first use to reinforce phenolic resin to form Bakelite. Since then thermoplastic and thermosetting composites have spread into almost every industry from marine to aerospace, automotive to motorsport, luggage to the hobby industry and even fashion. This vast range of applications for composite materials is due to their high strength to weight ratio, excellent impact absorption properties, lack of corrosion, and reformability. In recent years a government directive has forced automotive manufacturers to look at lighter and more efficient vehicles to reduce carbon emissions. This can be achieved by using fibre reinforced thermoplastics to replace steel panels throughout the vehicle.Steel panels from a Nissan Qashqai were tested to determine the failure loads of each panel which the replacement thermoplastic material had to match or better. After extensive testing in a laboratory a tailored laminate lay-up with 5 laminate layers has been developed to replace structural steel components in vehicles. This tailored laminate stack up has a higher failure load than the steel components tested from the Nissan Qashqai while reducing the mass by at least 50%. The key drivers within the automotive industry are fuel savings and reduced vehicle mass, the use of this material and the potential it has in the mass production automotive industry can have a high impact on the overall mass of the vehicle which would invariably have a positive effect to the fuel consumption, thereby improving fuel economy in petrol and diesel vehicles, and increasing the range of electric vehicles.Throughout this project a prototype machine was developed and built to achieve mass production of this 5 ply laminate at a rate of more than 345,000 laminates per year with a processing cost of 3 1p making it available to the mass production market. The estimated production

  6. Continuous Hydrogen Production from Agricultural Wastewaters at Thermophilic and Hyperthermophilic Temperatures.

    Science.gov (United States)

    Ramos, Lucas Rodrigues; Silva, Edson Luiz

    2017-06-01

    The objective of this study was to investigate the effects of hydraulic retention time (HRT) (8 to 0.5 h) and temperature (55 to 75 °C) in two anaerobic fluidized bed reactors (AFBR) using cheese whey (AFBR-CW = 10,000 mg sugars L -1 ) and vinasse (AFBR-V = 10,000 mg COD L -1 ) as substrates. Decreasing the HRT to 0.5 h increased the hydrogen production rates in both reactors, with maximum values of 5.36 ± 0.81 L H 2 h -1 L -1 in AFBR-CW and 0.71 ± 0.16 L H 2 h -1 L -1 in AFBR-V. The optimal conditions for hydrogen production were the HRT of 4 h and temperature of 65 °C in AFBR-CW, observing maximum hydrogen yield (HY) of 5.51 ± 0.37 mmol H 2 g COD -1 . Still, the maximum HY in AFBR-V was 1.64 ± 0.22 mmol H 2 g COD -1 at 4 h and 55 °C. However, increasing the temperature to 75 °C reduced the hydrogen production in both reactors. Methanol and butyric, acetic, and lactic acids were the main metabolites at temperatures of 55 and 65 °C, favoring the butyric and acetic metabolic pathways of hydrogen production. The increased productions of lactate, propionate, and methanol at 75 °C indicate that the hydrogen-producing bacteria in the thermophilic inoculum were inhibited under hyperthermophilic conditions.

  7. Renewable Bio-Solar Hydrogen Production: The Second Generation (Part B)

    Science.gov (United States)

    2015-03-20

    SUBJECT TERMS Biohydrogen, biofuels, cyanobacteria, photosynthesis, fermentation , transcription profiling, metabolic engineering, TCA cycle...transcription regulators, including RbcR, Fur, and ChlR, were identified and characterized, and a global model of the transcription network was...enhance hydrogen production. These data have recently been analyzed to produce a global transcription network model for this cyanobacterium [17]. At

  8. Agents Modeling Experience Applied To Control Of Semi-Continuous Production Process

    Directory of Open Access Journals (Sweden)

    Gabriel Rojek

    2014-01-01

    Full Text Available The lack of proper analytical models of some production processes prevents us from obtaining proper values of process parameters by simply computing optimal values. Possible solutions of control problems in such areas of industrial processes can be found using certain methods from the domain of artificial intelligence: neural networks, fuzzy logic, expert systems, or evolutionary algorithms. Presented in this work, a solution to such a control problem is an alternative approach that combines control of the industrial process with learning based on production results. By formulating the main assumptions of the proposed methodology, decision processes of a human operator using his experience are taken into consideration. The researched model of using and gathering experience of human beings is designed with the contribution of agent technology. The presented solution of the control problem coincides with case-based reasoning (CBR methodology.

  9. UNUSUAL WATER PRODUCTION ACTIVITY OF COMET C/2012 S1 (ISON): OUTBURSTS AND CONTINUOUS FRAGMENTATION

    International Nuclear Information System (INIS)

    Combi, M. R.; Fougere, N.; Mäkinen, J. T. T.; Bertaux, J.-L.; Quémerais, E.; Ferron, S.

    2014-01-01

    The Solar Wind ANisotropies (SWAN) all-sky hydrogen Lyα camera on the SOlar and Heliospheric Observer (SOHO) satellite observed the hydrogen coma of comet C/2012 S1 (ISON) for most of the last month of its activity from 2013 October 24 to November 24, ending just 4 days before perihelion and its final disruption. The water production rate of the comet was determined from these observations. SOHO has been operating in a halo orbit around the Earth-Sun L1 Lagrange point since its launch in late 1995. Most water vapor produced by comets is ultimately photodissociated into two H atoms and one O atom producing a huge hydrogen coma that is routinely observed in the daily SWAN images in comets of sufficient brightness. Water production rates were calculated from 22 images over most of the last month of the pre-perihelion apparition. The water production rate increased very slowly on average from October 24.9 until November 12.9, staying between 1.8 and 3.4 × 10 28  s –1 , after which it increased dramatically, reaching 1.6 to 2 × 10 30  s –1 from November 21.6 to 23.6. It was not detected after perihelion on December 3.7 when it should have been visible. We examine the active surface area necessary to explain the water production rate and its variation and are able to place constraints on the physical size of the original nucleus necessary to account for the large amount of activity from November 12.9 and until just before perihelion

  10. IUFRO Symposium on forest site and continuous productivity: Seattle, Washington, August 22-28, 1982.

    Science.gov (United States)

    Russell Ballard; Stanley P. Gessel

    1983-01-01

    This Symposium was planned by members of the IUFRO Site Group (S1.02) as part of their on-going activities to facilitate the worldwide exchange of ideas among individual research workers and to promote the dissemination of research results in the area of forest site productivity. The Symposium consisted of three days of indoor sessions followed by a 2-1/2-day field...

  11. Development of an advanced, continuous mild-gasification process for the production of coproducts

    Energy Technology Data Exchange (ETDEWEB)

    Merriam, N.W. (Western Research Inst., Laramie, WY (United States)); Jha, Mahesh C. (AMAX Research and Development Center, Golden, CO (United States))

    1991-11-01

    This report contains descriptions of mild-gasification and char-to-carbon process research units (PRUS) used by WRI and AMAX R D Center to conduct tests under contract AC21-87MC24268. Descriptions of materials produced during those tests are also contained herein. Western Research Institute proposes to dispose of remaining fines and dried coal by combustion and remaining coal liquids by incineration during mid-1992. The mild-gasification PRU will be used for additional tests until 1993, at which time WRI proposes to decontaminate and disassemble the PRU. AMAX R D Center intends to return the spent char, any remaining feed char, and unusable product carbon to the Eagle Butte Mine near Gillette, Wyoming, from where the coal originally came. The solid products will be added to the mine's coal product stream. Coal liquids collected from condensers will be concentrated and sent to a local oil and solvent recycling company where the liquids will be burned as fuel. The char-to-carbon PRU will be operated periodically until 1993 when the plant will be decontaminated and disassembled.

  12. Development of an advanced continuous mild gasification process for the production of coproducts

    Energy Technology Data Exchange (ETDEWEB)

    Jha, M.C.; McCormick, R.L.; Hogsett, R.F.; Rowe, R.M.; Anast, K.R.

    1991-12-01

    This document describes the results of Task 4 under which a 50 pound/hour char-to-carbon (CTC) process research unit (PRU) was designed in the second half of 1989, with construction completed in June 1990. The CTC PRU at Golden was operated for nearly one year during which 35 runs were completed for a total of nearly 800 hours of operation. Char methanation and carbon production reactor development activities are detailed in this report, as well as the results of integrated runs of the CTC process. Evaluation of the process and the carbon product produced is also included. It was concluded that carbon could be produced from mild gasification char utilizing the CTC process. Char methanation and membrane separation steps performed reasonably well and can scaled up with confidence. However, the novel directly heated reactor system for methane cracking did not work satisfactorily due to materials of construction and heat transfer problems, which adversely affected the quantity and quality of the carbon product. Alternative reactor designs are recommended.

  13. Continuous production of lactic acid from molasses by perfusion culture of Lactococcus lactis using a stirred ceramic membrane reactor.

    Science.gov (United States)

    Ohashi, R; Yamamoto, T; Suzuki, T

    1999-01-01

    A perfusion culture system was used for continuous production of lactic acid by retaining cells at a high density of Lactococcus lactis in a stirred ceramic membrane reactor (SCMR). After the cell concentration increased to 248 g/l, half of the culture broth volume was replaced with the fermentation medium. Subsequently, a substrate solution containing glucose (run 1) or molasses (run 2) was continuously supplied to the cells retained in the SCMR. Simultaneously, the culture supernatant was extracted using a ceramic filter with a pore size of 0.2 mum. The dilution rate was initially set at 0.4 h(-1) and gradually decreased to 0.2 h(-1) due to reduction in the permeability of the filter. The concentration of glucose in the substrate solution was adjusted to 60 g/l for the transition and the first period until 240 h, 90 g/l for the second period from 240 h to 440 h, and 70 g/l for the third period from 440 h to 643 h. The average concentration of lactic acid in the filtrate reached 46 g/l in the first period, 43 g/l in the second period, and 33 g/l for the third period. The productivity obtained for the first period reached 15.8 g.l(-1).h(-1), twice as much as that achieved in repeated batch fermentations. Based on the results obtained in run 1, the substrate solution containing 120 g/l of molasses was continuously supplied for 240 h in run 2. The concentration and productivity of lactic acid reached 40 g/l and 10.6 g.l(-1).h(-1), respectively, by continuously replenishing the culture medium at a dilution rate of 0.26 h(-1). These results demonstrated that the filtration capacity of the SCMR was sufficient for a continuous and rapid replenishment of molasses solution from the dense cell culture and, therefore, the perfusion culture system is considered to provide a low-cost process for continuous production of lactic acid from cheap resources.

  14. Hydrogen production by Escherichia coli {delta}hycA {delta}lacI using cheese whey as substrate

    Energy Technology Data Exchange (ETDEWEB)

    Rosales-Colunga, Luis Manuel; Ordonez, Leandro G.; De Leon-Rodriguez, Antonio (Division de Biologia Molecular, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la Presa San Jose 2055, Col. Lomas 4a secc. CP 78216, San Luis Potosi, SLP. Mexico); Razo-Flores, Elias; Alatriste-Mondragon, Felipe (Division de Ciencias Ambientales, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la Presa San Jose 2055, Col. Lomas 4a secc. CP 78216, San Luis Potosi, SLP. Mexico)

    2010-01-15

    This study reports a fermentative hydrogen production by Escherichia coli using cheese whey as substrate. To improve the biohydrogen production, an E. coli {delta}hycA {delta}lacI strain (WDHL) was constructed. The absence of hycA and lacI genes had a positive effect on the biohydrogen production. The strain produced 22% more biohydrogen in a shorter time than the wild-type (WT) strain. A Box-Behnken experimental design was used to optimize pH, temperature and substrate concentration. The optimal initial conditions for biohydrogen production by WDHL strain were pH 7.5, 37 C and 20 g/L of cheese whey. The specific production rate was improved from 3.29 mL H{sub 2}/optical density at 600 nm (OD{sub 600nm}) unit-h produced by WDHL under non-optimal conditions to 5.88 mL H{sub 2}/OD{sub 600nm} unit-h under optimal conditions. Using optimal initial conditions, galactose can be metabolized by WDHL strain. The maximum yield obtained was 2.74 mol H{sub 2}/mol lactose consumed, which is comparable with the yield reached in other hydrogen production processes with Clostridium sp. or mixed cultures. (author)

  15. Neutron cross section library production code system for continuous energy Monte Carlo code MVP. LICEM

    International Nuclear Information System (INIS)

    Mori, Takamasa; Nakagawa, Masayuki; Kaneko, Kunio.

    1996-05-01

    A code system has been developed to produce neutron cross section libraries for the MVP continuous energy Monte Carlo code from an evaluated nuclear data library in the ENDF format. The code system consists of 9 computer codes, and can process nuclear data in the latest ENDF-6 format. By using the present system, MVP neutron cross section libraries for important nuclides in reactor core analyses, shielding and fusion neutronics calculations have been prepared from JENDL-3.1, JENDL-3.2, JENDL-FUSION file and ENDF/B-VI data bases. This report describes the format of MVP neutron cross section library, the details of each code in the code system and how to use them. (author)

  16. Microwave-assisted pyrolysis of methyl ricinoleate for continuous production of undecylenic acid methyl ester (UAME).

    Science.gov (United States)

    Nie, Yong; Duan, Ying; Gong, Ruchao; Yu, Shangzhi; Lu, Meizhen; Yu, Fengwen; Ji, Jianbing

    2015-06-01

    Undecylenic acid methyl ester (UAME) was continuously produced from methyl ricinoleate using a microwave-assisted pyrolysis system with atomization feeding. The UAME yield of 77 wt.% was obtained at 500°C using SiC as the microwave absorbent and heating medium. The methyl ricinoleate conversion and UAME yield from microwave-assisted pyrolysis process were higher than those from conventional pyrolysis. The effect of temperature on the pyrolysis process was also investigated. The methyl ricinoleate conversion increased but the cracking liquid yield decreased when the temperature increased from 460°C to 560°C. The maximum UAME yield was obtained at the temperature of 500°C. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Cellulase enzyme production during continuous culture growth of Sporotrichum (Chrysosporium) thermophile

    Energy Technology Data Exchange (ETDEWEB)

    Cossar, D; Canevascini, G

    1986-07-01

    The cellulolytic fungus Sporotrichum (Chrysosporium) thermophile produces an extracellular cellobiose dehydrogenase during batch culture on cellulose or cellobiose. In chemostat culture at pH 5.6 on cellobiose this enzyme was produced in parallel with endo-cellulase. At pH 5.0 in continuous or fed-batch culture such a pattern was not evident. At constant growth rate in a chemostat with varying pH, activity of these enzymes was found to be poorly correlated. Thus the induction of cellobiose dehydrogenase shows a dependence on pH and cellobiose concentration which is different to that for endo-cellulase. The natural inducer of these enzymes and the role of cellubiose dehydrogenase remain to be elucidated.

  18. The production and growth characteristics of yeast and mycelial forms of Candida albicans in continuous culture.

    Science.gov (United States)

    Shepherd, M G; Sullivan, P A

    1976-04-01

    The growth characteristics of Candida albicans CM145,348 have been examined under aerobic conditions in continuous culture. At different steady states the environment was controlled with respect to the concentrations of dissolved oxygen, carbon and nitrogen, the pH, and the temperature. Dry matter, substrate concentration, yield, specific oxygen uptake, specific carbon dioxide release and respiration quotient were examined as a function of the dilution rate. The morphology depended on the carbon source. Maltose produced a mycelial morphology, whereas with lactate a yeast culture was obtained. With fructose or glucose as a carbon source a mixed morphology of yeast, pseudo-mycelial and mycelial forms was produced. A larger number of different growth conditions were examined in batch culture but a mixed morphology was always obtained.

  19. Neutron cross section library production code system for continuous energy Monte Carlo code MVP. LICEM

    Energy Technology Data Exchange (ETDEWEB)

    Mori, Takamasa; Nakagawa, Masayuki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kaneko, Kunio

    1996-05-01

    A code system has been developed to produce neutron cross section libraries for the MVP continuous energy Monte Carlo code from an evaluated nuclear data library in the ENDF format. The code system consists of 9 computer codes, and can process nuclear data in the latest ENDF-6 format. By using the present system, MVP neutron cross section libraries for important nuclides in reactor core analyses, shielding and fusion neutronics calculations have been prepared from JENDL-3.1, JENDL-3.2, JENDL-FUSION file and ENDF/B-VI data bases. This report describes the format of MVP neutron cross section library, the details of each code in the code system and how to use them. (author).

  20. A novel gas separation integrated membrane bioreactor to evaluate the impact of self-generated biogas recycling on continuous hydrogen fermentation

    International Nuclear Information System (INIS)

    Bakonyi, Péter; Buitrón, Germán; Valdez-Vazquez, Idania; Nemestóthy, Nándor; Bélafi-Bakó, Katalin

    2017-01-01

    Highlights: • A Gas Separation Membrane Bioreactor was designed to improve H_2 production. • Headspace gas after enrichment by PDMS membranes was used for reactor sparging. • Stripping the bioreactor with a CO_2-enriched gas enhanced the H_2 fermentation. - Abstract: A Gas Separation Membrane Bioreactor (GSMBR) by integrating membrane technology with a continuous biohydrogen fermenter was designed. The feasibility of this novel configuration for the improvement of hydrogen production capacity was tested by stripping the fermentation liquor with CO_2- and H_2-enriched gases, obtained directly from the bioreactor headspace. The results indicated that sparging the bioreactor with the CO_2-concentrated fraction of the membrane separation unit (consisting of two PDMS modules) enhanced the steady-state H_2 productivity (8.9–9.2 L H_2/L-d) compared to the membrane-less control CSTR to be characterized with 6.96–7.35 L H_2/L-d values. On the other hand, purging with the H_2-rich gas strongly depressed the achievable productivity (2.7–3.03 L H_2/L-d). Microbial community structure and soluble metabolic products were monitored to assess the GSMBR behavior. The study demonstrated that stripping the bioH_2 fermenter with its own, self-generated atmosphere after adjusting its composition (to higher CO_2-content) can be a promising way to intensify dark fermentative H_2 evolution.

  1. Continuous volatile fatty acid production from lignocellulosic biomass by a novel rumen-mimetic bioprocess.

    Science.gov (United States)

    Agematu, Hitosi; Takahashi, Takehiko; Hamano, Yoshio

    2017-11-01

    Lignocellulosic biomass is an attractive source of biofuels and biochemicals, being abundant in various plant sources. However, processing this type of biomass requires hydrolysis of cellulose. The proposed rumen-mimetic bioprocess consists of dry-pulverization of lignocellulosic biomass and pH-controlled continuous cultivation of ruminal bacteria using ammonium as a nitrogen source. In this study, ruminal bacteria were continuously cultivated for over 60 days and used to digest microcrystalline cellulose, rice straw, and Japanese cedar to produce volatile fatty acids (VFAs). The ruminal bacteria grew well in the chemically defined medium. The amounts of VFAs produced from 20 g of cellulose, rice straw, and Japanese cedar were 183 ± 29.7, 69.6 ± 12.2, and 21.8 ± 12.9 mmol, respectively. Each digestion completed within 24 h. The carbon yield was 60.6% when 180 mmol of VFAs was produced from 20 g of cellulose. During the cultivation, the bacteria were observed to form flocs that enfolded the feed particles. These flocs likely contain all of the bacterial species necessary to convert lignocellulosic biomass to VFAs and microbial protein symbiotically. Denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified 16S rDNA fragments revealed that the bacterial community was relatively stable after 1 week in cultivation, though it was different from the original community structure. Furthermore, sequence analysis of the DGGE bands indicates that the microbial community includes a cellulolytic bacterium, a bacterium acting synergistically with cellulolytic bacteria, and a propionate-producing bacterium, as well as other anaerobic bacteria. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  2. A continuous hyperspatial monitoring system of evapotranspiration and gross primary productivity from Unmanned Aerial Systems

    Science.gov (United States)

    Wang, Sheng; Bandini, Filippo; Jakobsen, Jakob; Zarco-Tejada, Pablo J.; Köppl, Christian Josef; Haugård Olesen, Daniel; Ibrom, Andreas; Bauer-Gottwein, Peter; Garcia, Monica

    2017-04-01

    Unmanned Aerial Systems (UAS) can collect optical and thermal hyperspatial (challenges for an operational monitoring using UAS compared to satellites: the payload capacity of most commercial UAS is less than 2 kg, but miniaturized sensors have low signal to noise ratios and small field of view requires mosaicking hundreds of images and accurate orthorectification. In addition, wind gusts and lower platform stability require appropriate geometric and radiometric corrections. Finally, modeling fluxes on days without images is still an issue for both satellite and UAS applications. This study focuses on designing an operational UAS-based monitoring system including payload design, sensor calibration, based on routine collection of optical and thermal images in a Danish willow field to perform a joint monitoring of ET and GPP dynamics over continuous time at daily time steps. The payload (approach (Potter et al., 1993). Both models estimate ET and GPP under optimum potential conditions down-regulated by the same biophysical constraints dependent on remote sensing and atmospheric data to reflect multiple stresses. Vegetation indices were calculated from the multispectral data to assess vegetation conditions, while thermal infrared imagery was used to compute a thermal inertia index to infer soil moisture constraints. To interpolate radiometric temperature between flights, a prognostic Surface Energy Balance model (Margulis et al., 2001) based on the force-restore method was applied in a data assimilation scheme to obtain continuous ET and GPP fluxes. With this operational system, regular flight campaigns with a hexacopter (DJI S900) have been conducted in a Danish willow flux site (Risø) over the 2016 growing season. The observed energy, water and carbon fluxes from the Risø eddy covariance flux tower were used to validate the model simulation. This UAS monitoring system is suitable for agricultural management and land-atmosphere interaction studies.

  3. Operational Improvements of Continuous Process with Tools of Lean Production - A Case Study in a Brazilian Petrochemical

    Directory of Open Access Journals (Sweden)

    Francisco Uchoa Passos

    2013-06-01

    Full Text Available This study seeks to evaluate operational improvements in Brazilian petrochemical company Braskem, which has been using lean production management tools to monitor its processes. There was some improvement in plant efficiency, measured from the beginning of implementation of management tools Six Sigma and TPM. Thus, we investigated three efficiency indicators considered by the company of great importance for the competitiveness of the business: the physical loss of products, plant’s energy efficiency, and the utilization rate of assets. The differences observed in these indicators, before and after the use of the tools, were tested for its statistical significance, which revealed that the physical losses of ethylene and plant’s energy efficiency improved, almost reaching the performance considered as class world. As for the utilization rate of assets, although it has evolved positively, still is at a considerable distance from that performance standard. By registering operational improvements in a continuous process plant, with lean production tools, this study indicates that these instruments, even if they have no causal relation with the improvements, are suitable for continuous processes and could have a much broader use, oriented, first of all, by the general approach of process optimization and, somehow, regardless of the nature of productive activity.

  4. Ecology versus economy: is biohydrogen the fuel of the future?; Ecologia contra Economia: ¿es el biohidrogeno el combustible del futuro?

    Energy Technology Data Exchange (ETDEWEB)

    Patino, Rodrigo [Centro de Investigacion y de Estudios Avanzados, Unidad Merida, Merida, Yucatan (Mexico)] e-mail: rtarkus@mda.cinvestav.mx

    2009-09-15

    This work presents a literature review of scientific research on different methodologies developed to produce hydrogen. Current processes to obtain commercial hydrogen are completely unsustainable in terms of the use of natural resources and environmental degradation. Different bioprocesses have been proposed in recent years as environmentally clean alternatives to produce combustible gases, but balance has not yet been obtained between production costs and performance. Therefore, a comparative analysis is performed of the different methods to obtain hydrogen, their limitations and the future prospects for each one. An in-depth reflection is also provided about challenges and recommendations for scientific and technological research aimed at proposing hydrogen (or biohydrogen) as the substitute for fossil fuels over the course of the 21st century, including not only its production but also storage and energy transformation mechanisms. [Spanish] En este trabajo se presenta una revision bibliografica acerca de las distintas metodologias desarrolladas en investigacion cientifica para producir hidrogeno. Los procesos actuales por los que se obtiene hidrogeno comercial son completamente insostenibles en cuanto a la utilizacion de recursos naturales y deterioro del medio ambiente. En los ultimos anos se han propuesto distintos bioprocesos como alternativas medioambientalmente limpias para la produccion del combustible gaseoso, pero aun no se llega a obtener un balance entre los costos y los rendimientos de produccion. Se hace entonces un analisis comparativo de los distintos metodos de obtencion de hidrogeno, de las limitantes presentes y las perspectivas futuras para cada uno de ellos. Tambien se hace una profunda reflexion acerca del reto y la orientacion que deben tener las investigaciones cientificas y tecnologicas para proponer al hidrogeno (o al biohidrogeno) como el combustible que deba sustituir a los combustibles fosiles durante el transcurso del siglo XXI

  5. Maximizing the productivity of the microalgae Scenedesmus AMDD cultivated in a continuous photobioreactor using an online flow rate control.

    Science.gov (United States)

    McGinn, Patrick J; MacQuarrie, Scott P; Choi, Jerome; Tartakovsky, Boris

    2017-01-01

    In this study, production of the microalga Scenedesmus AMDD in a 300 L continuous flow photobioreactor was maximized using an online flow (dilution rate) control algorithm. To enable online control, biomass concentration was estimated in real time by measuring chlorophyll-related culture fluorescence. A simple microalgae growth model was developed and used to solve the optimization problem aimed at maximizing the photobioreactor productivity. When optimally controlled, Scenedesmus AMDD culture demonstrated an average volumetric biomass productivity of 0.11 g L -1  d -1 over a 25 day cultivation period, equivalent to a 70 % performance improvement compared to the same photobioreactor operated as a turbidostat. The proposed approach for optimizing photobioreactor flow can be adapted to a broad range of microalgae cultivation systems.

  6. Continuous production of inorganic magnetic nanocomposites for biomedical applications by laser pyrolysis

    International Nuclear Information System (INIS)

    Veintemillas-Verdaguer, Sabino; Leconte, Yann; Costo, Rocio; Bomati-Miguel, Oscar; Bouchet-Fabre, Brigitte; Morales, M. Puerto; Bonville, Pierre; Perez-Rial, Sandra; Rodriguez, Ignacio; Herlin-Boime, Nathalie

    2007-01-01

    Magnetic composites of Fe-based nanoparticles encapsulated in carbon/silica (C/SiO 2 at Fe) or carbon (C at Fe) matrices were prepared by laser-induced pyrolysis of aerosols. The powders were dispersed in aqueous solutions at pH 7 resulting in biocompatible colloidal dispersions with a high resistance to biodegradation. Structural and magnetic properties and the suitability of aqueous dispersions as contrast agent for MRI were analyzed. The results of these characterizations and the NMR relaxivity data are very encouraging for application of laser pyrolysis products in the field of living tissues

  7. Continuous citric acid production in repeated-fed batch fermentation by Aspergillus niger immobilized on a new porous foam.

    Science.gov (United States)

    Yu, Bin; Zhang, Xin; Sun, Wenjun; Xi, Xun; Zhao, Nan; Huang, Zichun; Ying, Zhuojun; Liu, Li; Liu, Dong; Niu, Huanqing; Wu, Jinglan; Zhuang, Wei; Zhu, Chenjie; Chen, Yong; Ying, Hanjie

    2018-03-24

    The efficiency of current methods for industrial production of citric acid is limited. To achieve continuous citric acid production with enhanced yield and reduced cost, immobilized fermentation was employed in an Aspergillus niger 831 repeated fed-batch fermentation system. We developed a new type of material (PAF201), which was used as a carrier for the novel adsorption immobilization system. Hydrophobicity, pore size and concentration of carriers were researched in A. niger immobilization. The efficiency of the A. niger immobilization process was analyzed by scanning electron microscopy. Then eight-cycle repeated fed-batch cultures for citric acid production were carried out over 600 h, which showed stable production with maximum citric acid concentrations and productivity levels of 162.7 g/L and 2.26 g L -1  h -1 , respectively. Compared with some other literatures about citric acid yield, PAF201 immobilization system is 11.3% higher than previous results. These results indicated that use of the new adsorption immobilization system could greatly improve citric acid productivity in repeated fed-batch fermentation. Moreover, these results could provide a guideline for A.niger or other filamentous fungi immobilization in industry. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. NASA's MODIS/VIIRS Land Surface Temperature and Emissivity Products: Asssessment of Accuracy, Continuity and Science Uses

    Science.gov (United States)

    Hulley, G. C.; Malakar, N.; Islam, T.

    2017-12-01

    Land Surface Temperature and Emissivity (LST&E) are an important Earth System Data Record (ESDR) and Environmental Climate Variable (ECV) defined by NASA and GCOS respectively. LST&E data are key variables used in land cover/land use change studies, in surface energy balance and atmospheric water vapor retrieval models and retrievals, and in climate research. LST&E products are currently produced on a routine basis using data from the MODIS instruments on the NASA EOS platforms and by the VIIRS instrument on the Suomi-NPP platform that serves as a bridge between NASA EOS and the next-generation JPSS platforms. Two new NASA LST&E products for MODIS (MxD21) and VIIRS (VNP21) are being produced during 2017 using a new approach that addresses discrepancies in accuracy and consistency between the current suite of split-window based LST products. The new approach uses a Temperature Emissivity Separation (TES) algorithm, originally developed for the ASTER instrument, to physically retrieve both LST and spectral emissivity consistently for both sensors with high accuracy and well defined uncertainties. This study provides a rigorous assessment of accuracy of the MxD21/VNP21 products using temperature- and radiance-based validation strategies and demonstrates continuity between the products using collocated matchups over CONUS. We will further demonstrate potential science use of the new products with studies related to heat waves, monitoring snow melt dynamics, and land cover/land use change.

  9. Animal use in the chemical and product manufacturing sectors - can the downtrend continue?

    Science.gov (United States)

    Curren, Rodger

    2009-12-01

    During the 1990s and early 2000s, a number of manufacturing companies in the cosmetic, personal care and household product industries were able to substantially reduce their use of animals for testing (or to not use animals in the first place). These reductions were almost always the result of significant financial contributions to either direct, in-house alternatives research, or to support personnel whose duties were to understand and apply the current state-of-the-art for in vitro testing. They occurred almost exclusively in non-regulatory areas, and primarily involved acute topical toxicities. Over the last few years, the reduction in animal use has been much less dramatic, because some companies are still reluctant to change from the traditional animal studies, because systemic, repeat-dose toxicity is more difficult to model in vitro, and because many products still require animal testing for regulatory approval. Encouragingly, we are now observing an increased acceptance of non-animal methods by regulatory agencies. This is due to mounting scientific evidence from larger databases, agreement by companies to share data and testing strategies with regulatory agencies, and a focus on smaller domains of applicability. These changes, along with new emphasis and financial support for addressing systemic toxicities, promise to provide additional possibilities for industry to replace animals with in vitro methods, alone or in combination with in silico methods. However, the largest advance will not occur until more companies commit to using the non-animal test strategies that are currently available. 2009 FRAME.

  10. Continuous ethanol production using yeast immobilized on sugar-cane stalks

    Energy Technology Data Exchange (ETDEWEB)

    Vasconcelos, J.N. de [Alagoas Univ., Maceio, AL (Brazil). Dept. de Engenharia Quimica]. E-mail: jnunes@ctec.ufal.br; Lopes, C.E. [Pernambuco Univ., Recife, PE (Brazil). Dept. de Antibioticos; Franca, F.P. de [Universidade Federal, Rio de Janeiro, RJ (Brazil). Escola de Quimica. Dept. de Engenharia Bioquimica

    2004-09-01

    Sugar-cane stalks, 2.0 cm long, were used as a support for yeast immobilization envisaging ethanol production. The assays were conducted in 38.5 L fermenters containing a bed of stalks with 50% porosity. The operational stability of the immobilized yeast, the efficiency and stability of the process, as well as the best dilution rate were evaluated. Molasses from demerara sugar production was used in the medium formulation. It was diluted to obtain 111.75 {+-} 1.51 g/L without any further treatment. Sulfuric acid was used to adjust the pH value to around 4.2. Every two days Kamoran HJ (10 ppm) or with a mixture containing penicillin (10 ppm) and tetracycline (10 ppm), was added to the medium. Ethanol yield and efficiency were 29.64 g/L.h and 86.40%, respectively, and the total reducing sugars conversion was 74.61% at a dilution rate of 0.83 h{sup -1}. The yeast-stalk system was shown to be stable for over a 60 day period at extremely variable dilution rates ranging from 0.05 h{sup -1} to 3.00 h{sup -1}. The concentration of immobilized cell reached around 109 cells/gram of dry sugar-cane stalk when the fermenter was operating at the highest dilution rate (3.00 h{sup -1}). (author)

  11. Design of a continuous process setup for precipitated calcium carbonate production from steel converter slag.

    Science.gov (United States)

    Mattila, Hannu-Petteri; Zevenhoven, Ron

    2014-03-01

    A mineral carbonation process "slag2PCC" for carbon capture, utilization, and storage is discussed. Ca is extracted from steel slag by an ammonium salt solvent and carbonated with gaseous CO2 after the separation of the residual slag. The solvent is reused after regeneration. The effects of slag properties such as the content of free lime, fractions of Ca, Si, Fe, and V, particle size, and slag storage on the Ca extraction efficiency are studied. Small particles with a high free-lime content and minor fractions of Si and V are the most suitable. To limit the amount of impurities in the process, the slag-to-liquid ratio should remain below a certain value, which depends on the slag composition. Also, the design of a continuous test setup (total volume ∼75 L) is described, which enables quick process variations needed to adapt the system to the varying slag quality. Different precipitated calcium carbonate crystals (calcite and vaterite) are generated in different parts of the setup. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Active pharmaceutical ingredient (API) production involving continuous processes--a process system engineering (PSE)-assisted design framework.

    Science.gov (United States)

    Cervera-Padrell, Albert E; Skovby, Tommy; Kiil, Søren; Gani, Rafiqul; Gernaey, Krist V

    2012-10-01

    A systematic framework is proposed for the design of continuous pharmaceutical manufacturing processes. Specifically, the design framework focuses on organic chemistry based, active pharmaceutical ingredient (API) synthetic processes, but could potentially be extended to biocatalytic and fermentation-based products. The method exploits the synergic combination of continuous flow technologies (e.g., microfluidic techniques) and process systems engineering (PSE) methods and tools for faster process design and increased process understanding throughout the whole drug product and process development cycle. The design framework structures the many different and challenging design problems (e.g., solvent selection, reactor design, and design of separation and purification operations), driving the user from the initial drug discovery steps--where process knowledge is very limited--toward the detailed design and analysis. Examples from the literature of PSE methods and tools applied to pharmaceutical process design and novel pharmaceutical production technologies are provided along the text, assisting in the accumulation and interpretation of process knowledge. Different criteria are suggested for the selection of batch and continuous processes so that the whole design results in low capital and operational costs as well as low environmental footprint. The design framework has been applied to the retrofit of an existing batch-wise process used by H. Lundbeck A/S to produce an API: zuclopenthixol. Some of its batch operations were successfully converted into continuous mode, obtaining higher yields that allowed a significant simplification of the whole process. The material and environmental footprint of the process--evaluated through the process mass intensity index, that is, kg of material used per kg of product--was reduced to half of its initial value, with potential for further reduction. The case-study includes reaction steps typically used by the pharmaceutical

  13. Using reaction-technical models for characterisation and optimisation of continuous ethanol production with biomass recirculation

    Energy Technology Data Exchange (ETDEWEB)

    Yayanata, Y

    1983-11-28

    Ethanol production from S. cerevisiae was studied experimentally in one- and two-stage plants, with and without biomass recirculation. The hydrogen sources were glucose and molasses. The experimental findings were used as a basis for mathematical models whose kinetic parameters were established by comparison with the experiments. In the fermentation processes with glucose as carbon and energy source, an activation kinetics of yeast extract was considered in addition to the limitations resulting from the substrate and the inhibition by the produced ethanol. The problem of biomass recirculation received particular attention. Lamellar separators in the form of a cated tube cluster are described as an alternative to conventional conical separator tanks. Biomass concentrations in the fermenter may amount to about 80 gTS/l. Satisfactory simulation of the plant behaviour is possible by combining the kinetic approaches for the fermenter with the mathematical models for the separator.

  14. Finite-size effects on two-particle production in continuous and discrete spectrum

    CERN Document Server

    Lednicky, R

    2005-01-01

    The effect of a finite space-time extent of particle production region on the lifetime measurement of hadronic atoms produced by a high energy beam in a thin target is discussed. Particularly, it is found that the neglect of this effect on the pionium lifetime measurement in the experiment DIRAC at CERN could lead to the lifetime overestimation on the level of the expected 10% statistical error. It is argued that the data on correlations of identical particles obtained in the same experimental conditions, together with transport code simulation, allow to diminish the systematic error in the extracted lifetime to an acceptable level. The theoretical systematic errors arising in the calculation of the finite-size effect due to the neglect of non-equal emission times in the pair c.m.s., the space-time coherence and the residual charge are shown to be negligible.

  15. Analytical method used for intermediate products in continuous distillation of furfural

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z.L.; Jia, M.; Wang, L.J.; Deng, Y.X.

    1981-01-01

    During distillation of furfural, analysis of main components in the crude furfural condensate and intermediate products is very important. Since furfural and methylfurfural are homologous and both furfural and acetone contain a carbonyl group, components in the sample must be separated before analysis. An improved analytical method has been studied, the accuracy and precision of which would meet the requirement of industrial standards. The analytical procedure was provided as follows: to determine the furfural content with gravimetric method of barbituric acid; to determine the methanol content with dichromate method after precipitating furfural and acetone, and distilling the liquid for analysis; and to determine the methylfurfural content with bromide-bromate method, which can be used only in the sample containing higher content of methylfurfural. For the sample in low content, the gas-liquid chromatographic method can be used. 7 references.

  16. Sustainable data policy for a data production facility: a work in (continual) progress

    Science.gov (United States)

    Ketcham, R. A.

    2017-12-01

    The University of Texas High-Resolution X-Ray Computed Tomography Facility (UTCT) has been producing volumetric data and data products of geological and other scientific specimens and engineering materials for over 20 years. Data volumes, both in terms of the size of individual data sets and overall facility production, have progressively grown and fluctuated near the upper boundary of what can be managed by contemporary workstations and lab-scale servers and network infrastructure, making data policy a preoccupation for our entire history. Although all projects have been archived since our first day of operation, policies on which data to keep (raw, reconstructed after corrections, processed) have varied, and been periodically revisited in consideration of the cost of curation and the likelihood of revisiting and reprocessing data when better techniques become available, such as improved artifact corrections or iterative tomographic reconstruction. Advances in instrumentation regularly make old data obsolete and more advantageous to reacquire, but the simple act of getting a sample to a scanning facility is a practical barrier that cannot be overlooked. In our experience, the main times that raw data have been revisited using improved processing to improve image quality were predictable, high-impact charismatic projects (e.g., Archaeopteryx, A. Afarensis "Lucy"). These cases actually provided the impetus for development of the new techniques (ring and beam hardening artifact reduction), which were subsequently incorporated into our data processing pipeline going forward but were rarely if ever retroactively applied to earlier data sets. The only other times raw data have been reprocessed were when reconstruction parameters were inappropriate, due to unnoticed sample features or human error, which are usually recognized fairly quickly. The optimal data retention policy thus remains an open question, although erring on the side of caution remains the default

  17. Engineered catalytic biofilms for continuous large scale production of n-octanol and (S)-styrene oxide.

    Science.gov (United States)

    Gross, Rainer; Buehler, Katja; Schmid, Andreas

    2013-02-01

    This study evaluates the technical feasibility of biofilm-based biotransformations at an industrial scale by theoretically designing a process employing membrane fiber modules as being used in the chemical industry and compares the respective process parameters to classical stirred-tank studies. To our knowledge, catalytic biofilm processes for fine chemicals production have so far not been reported on a technical scale. As model reactions, we applied the previously studied asymmetric styrene epoxidation employing Pseudomonas sp. strain VLB120ΔC biofilms and the here-described selective alkane hydroxylation. Using the non-heme iron containing alkane hydroxylase system (AlkBGT) from P. putida Gpo1 in the recombinant P. putida PpS81 pBT10 biofilm, we were able to continuously produce 1-octanol from octane with a maximal productivity of 1.3 g L ⁻¹(aq) day⁻¹ in a single tube micro reactor. For a possible industrial application, a cylindrical membrane fiber module packed with 84,000 polypropylene fibers is proposed. Based on the here presented calculations, 59 membrane fiber modules (of 0.9 m diameter and 2 m length) would be feasible to realize a production process of 1,000 tons/year for styrene oxide. Moreover, the product yield on carbon can at least be doubled and over 400-fold less biomass waste would be generated compared to classical stirred-tank reactor processes. For the octanol process, instead, further intensification in biological activity and/or surface membrane enlargement is required to reach production scale. By taking into consideration challenges such as biomass growth control and maintaining a constant biological activity, this study shows that a biofilm process at an industrial scale for the production of fine chemicals is a sustainable alternative in terms of product yield and biomass waste production. Copyright © 2012 Wiley Periodicals, Inc.

  18. Ethanol production from biomass by repetitive solid-state fed-batch fermentation with continuous recovery of ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Moukamnerd, Churairat; Kino-oka, Masahiro; Sugiyama, Minetaka; Kaneko, Yoshinobu; Harashima, Satoshi; Katakura, Yoshio [Osaka Univ. (Japan). Dept. of Biotechnology; Boonchird, Chuenchit [Mahidol Univ., Bangkok (Thailand). Dept. of Biotechnology; Noda, Hideo [Kansai Chemical Engineering Co., Ltd., Amagasaki (Japan); Ninomiya, Kazuaki [Kanazawa Univ. (Japan). Inst. of International Environment Technology; Shioya, Suteaki [Sojo Univ., Kumamoto (Japan). Dept. of Applied Life Science

    2010-09-15

    To save cost and input energy for bioethanol production, a consolidated continuous solid-state fermentation system composed of a rotating drum reactor, a humidifier, and a condenser was developed. Biomass, saccharifying enzymes, yeast, and a minimum amount of water are introduced into the system. Ethanol produced by simultaneous saccharification and fermentation is c