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Sample records for stover residues process

  1. Bioethanol production from corn stover residues. Process design and Life Cycle Assessment

    International Nuclear Information System (INIS)

    De Bari, I.; Dinnino, G.; Braccio, G.

    2008-01-01

    In this report, the mass and energy balance along with a land-to-wheel Life Cycle Assessment (LCA) is described for a corn stover-to-ethanol industrial process assumed to consist of the main technologies being researched at ENEA TRISAIA: pretreatment by steam explosion and enzymatic hydrolysis. The modelled plant has a processing capacity of 60kt/y (dimensioned on realistic supplying basins of residues in Italy); biomass is pre-treated by acid catalyzed-steam explosion; cellulose and hemicelluloses are hydrolyzed and separately fermented; enzymes are on-site produced. The main target was to minimize the consumption of fresh water, enzymes and energy. The results indicate that the production of 1kg bio ethanol (95.4 wt%) requires 3.5 kg biomass dry matter and produces an energy surplus up to 740 Wh. The main purpose of the LCA analysis was to assess the environmental impact of the entire life cycle from the bio ethanol production up to its end-use as E10 blended gasoline. Boustead Model was used as tool to compile the life cycle inventory. The results obtained and discussed in this reports suffer of some limitations deriving from the following main points: some process yields have been extrapolated according to optimistic development scenarios; the energy and steam recovery could be lower than that projected because of lacks in the real systems; water recycle could be limited by the yeast tolerance toward the potential accumulation of toxic compounds. Nevertheless, the detailed process analysis here provided has its usefulness in: showing the challenging targets (even if they are ambitious) to bet on to make the integrated process feasible; driving the choice of the most suitable technologies to bypass some process bottlenecks [it

  2. Assessment of Antioxidant and Antimicrobial Properties of Lignin from Corn Stover Residue Pretreated with Low-Moisture Anhydrous Ammonia and Enzymatic Hydrolysis Process.

    Science.gov (United States)

    Guo, Mingming; Jin, Tony; Nghiem, Nhuan P; Fan, Xuetong; Qi, Phoebe X; Jang, Chan Ho; Shao, Lingxiao; Wu, Changqing

    2018-01-01

    Lignin accounts for 15-35% of dry biomass materials. Therefore, developing value-added co-products from lignin residues is increasingly important to improve the economic viability of biofuel production from biomass resources. The main objective of this work was to study the lignin extracts from corn stover residue obtained from a new and improved process for bioethanol production. Extraction conditions that favored high lignin yield were optimized, and antioxidant and antimicrobial activities of the resulting lignin were investigated. Potential estrogenic toxicity of lignin extracts was also evaluated. The corn stover was pretreated by low-moisture anhydrous ammonia (LMAA) and then subjected to enzymatic hydrolysis using cellulase and hemicellulase. The residues were then added with sodium hydroxide and extracted for different temperatures and times for enhancing lignin yield and the bioactivities. The optimal extraction conditions using 4% (w/v) sodium hydroxide were determined to be 50 °C, 120 min, and 1:8 (w:v), the ratio between corn stover solids and extracting liquid. Under the optimal condition, 33.92 g of lignin yield per 100 g of corn stover residue was obtained. Furthermore, the extracts produced using these conditions showed the highest antioxidant activity by the hydrophilic oxygen radical absorbance capacity (ORAC) assay. The extracts also displayed significant antimicrobial activities against Listeria innocua. Minimal estrogenic impacts were observed for all lignin extracts when tested using the MCF-7 cell proliferation assay. Thus, the lignin extracts could be used for antioxidant and antimicrobial applications, and improve the value of the co-products from the biomass-based biorefinery.

  3. Viscoelastic properties of microfibrillated cellulose (MFC) produced from agricultural residue corn stover

    Science.gov (United States)

    The rheological properties of microfibrillated cellulose (MFC) produced from agricultural residue corn stover were investigated. The corn stover MFC gels exhibited concentration-dependent viscoelastic properties. Higher corn stover MFC concentrations resulted in stronger viscoelastic properties. Th...

  4. Viscoelastic properties of microfibrillated cellulose (MFC) produced from agricultural residue corn stover

    Science.gov (United States)

    The rheological properties of microfibrillated cellulose (MFC) produced from agricultural residue corn stover were investigated. The corn stover MFC gels exhibited concentration-dependent viscoelastic solid properties. Higher corn stover MFC concentrations resulted in stronger viscoelastic propertie...

  5. Multipass rotary shear comminution process to produce corn stover particles

    Science.gov (United States)

    Dooley, James H; Lanning, David N

    2015-04-14

    A process of comminution of corn stover having a grain direction to produce a mixture of corn stover, by feeding the corn stover in a direction of travel substantially randomly to the grain direction one or more times through a counter rotating pair of intermeshing arrays of cutting discs (D) arrayed axially perpendicular to the direction of corn stover travel.

  6. Steam gasification of a thermally pretreated high lignin corn stover simultaneous saccharification and fermentation digester residue

    Energy Technology Data Exchange (ETDEWEB)

    Howe, Daniel T.; Taasevigen, Danny; Garcia-Perez, Manuel; McDonald, Armando G.; Li, Guosheng; Wolcott, Michael

    2017-01-01

    Efficient conversion of all components in lignocellulosic biomass is essential to realizing economic feasibility of biorefineries. However, when utilizing biochemical pathways, lignin cannot be fermented. Furthermore, the high lignin and high ash residue resulting from simultaneous saccharification and fermentation (SSF) reactors is difficult to thermochemically process due to feed line plugging and bed agglomeration. In this study a corn stover SSF digester residue was thermally pretreated at 300°C for 22.5 minutes (min) and then gasified in a bubbling fluidized bed gasifier to study the effect of thermal pretreatment on its processing behavior. Untreated, pelletized SSF residue was gasified at the same conditions to establish the baseline processing behavior. Results indicate that the thermal pretreatment process removes a substantial portion of the polar and non-polar extractives, with a resultant increase in the concentration of lignin, cellulose, and ash. Feed line plugging was not observed, although bed agglomeration was occurring at similar rates for both feedstocks, suggesting that overall ash content is the most important factor affecting bed agglomeration. Benzene, phenol, and polyaromatic hydrocarbons in the tar were present at higher concentrations in the treated material, with higher tar loading in the product gas. Total product gas generation is lower for the treated material, although the overall gas composition does not change.

  7. Reactor performance and energy analysis of solid state anaerobic co-digestion of dairy manure with corn stover and tomato residues.

    Science.gov (United States)

    Li, Yangyang; Xu, Fuqing; Li, Yu; Lu, Jiaxin; Li, Shuyan; Shah, Ajay; Zhang, Xuehua; Zhang, Hongyu; Gong, Xiaoyan; Li, Guoxue

    2018-03-01

    Anaerobic co-digestion is commonly believed to be benefical for biogas production. However, additional of co-substrates may require additional energy inputs and thus affect the overall energy efficiency of the system. In this study, reactor performance and energy analysis of solid state anaerobic digestion (SS-AD) of tomato residues with dairy manure and corn stover were investigated. Different fractions of tomato residues (0, 20, 40, 60, 80 and 100%, based on volatile solid weight (VS)) were co-digested with dairy manure and corn stover at 15% total solids. Energy analysis based on experimental data was conducted for three scenarios: SS-AD of 100% dairy manure, SS-AD of binary mixture (60% dairy manure and 40% corn stover, VS based), and SS-AD of ternary mixture (36% dairy manure, 24% corn stover, and 40% tomato residues, VS based). For each scenario, the energy requirements for individual process components, including feedstock collection and transportation, feedstock pretreatment, biogas plant operation, digestate processing and handling, and the energy production were examined. Results showed that the addition of 20 and 40% tomato residues increased methane yield compared to that of the dairy manure and corn stover mixture, indicating that the co-digestion could balance nutrients and improve the performance of solid-state anaerobic digestion. The energy required for heating substrates had the dominant effect on the total energy consumption. The highest volatile solids (VS) reduction (57.0%), methane yield (379.1 L/kg VS feed ), and net energy production were achieved with the mixture of 24% corn stover, 36% dairy manure, and 40% tomato residues. Thus, the extra energy input for adding tomato residues for co-digestion could be compensated by the increase of methane yield. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Residue processing

    Energy Technology Data Exchange (ETDEWEB)

    Gieg, W.; Rank, V.

    1942-10-15

    In the first stage of coal hydrogenation, the liquid phase, light and heavy oils were produced; the latter containing the nonliquefied parts of the coal, the coal ash, and the catalyst substances. It was the problem of residue processing to extract from these so-called let-down oils that which could be used as pasting oils for the coal. The object was to obtain a maximum oil extraction and a complete removal of the solids, because of the latter were returned to the process they would needlessly burden the reaction space. Separation of solids in residue processing could be accomplished by filtration, centrifugation, extraction, distillation, or low-temperature carbonization (L.T.C.). Filtration or centrifugation was most suitable since a maximum oil yield could be expected from it, since only a small portion of the let-down oil contained in the filtration or centrifugation residue had to be thermally treated. The most satisfactory centrifuge at this time was the Laval, which delivered liquid centrifuge residue and centrifuge oil continuously. By comparison, the semi-continuous centrifuges delivered plastic residues which were difficult to handle. Various apparatus such as the spiral screw kiln and the ball kiln were used for low-temperature carbonization of centrifuge residues. Both were based on the idea of carbonization in thin layers. Efforts were also being made to produce electrode carbon and briquette binder as by-products of the liquid coal phase.

  9. Assessment of antioxidant and antimicrobial properties of lignin from corn stover residue pretreated with low-moisture anhydrous ammonia and enzymatic hydrolysis process

    Science.gov (United States)

    To improve the economic viability of biofuel production from biomass resources, it is increasingly important to develop value-added lignin co-products from this process. The main objective of this study was to investigate the antimicrobial and antioxidant activities of the lignin extracts obtained b...

  10. Assessment of Potential Capacity Increases at Combined Heat and Power Facilities Based on Available Corn Stover and Forest Logging Residues

    Directory of Open Access Journals (Sweden)

    Donald L. Grebner

    2013-08-01

    Full Text Available Combined Heat and Power (CHP production using renewable energy sources is gaining importance because of its flexibility and high-energy efficiency. Biomass materials, such as corn stover and forestry residues, are potential sources for renewable energy for CHP production. In Mississippi, approximately 4.0 MT dry tons of woody biomass is available annually for energy production. In this study, we collected and analyzed 10 years of corn stover data (2001–2010 and three years of forest logging residue data (1995, 1999, and 2002 in each county in Mississippi to determine the potential of these feed stocks for sustainable CHP energy production. We identified six counties, namely Amite, Copiah, Clarke, Wayne, Wilkinson and Rankin, that have forest logging residue feedstocks to sustain a CHP facility with a range of capacity between 8.0 and 9.8 MW. Using corn stover alone, Yazoo and Washington counties can produce 13.4 MW and 13.5 MW of energy, respectively. Considering both feedstocks and based on a conservative amount of 30% available forest logging residue and 33% corn stover, we found that 20 counties have adequate supply for a CHP facility with a capacity of 8.3 MW to 19.6 MW.

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

    Science.gov (United States)

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

  12. Soaking pretreatment of corn stover for bioethanol production followed by anaerobic digestion process.

    Science.gov (United States)

    Zuo, Zhuang; Tian, Shen; Chen, Zebing; Li, Jia; Yang, Xiushan

    2012-08-01

    The production of ethanol and methane from corn stover (CS) was investigated in a biorefinery process. Initially, a novel soaking pretreatment (NaOH and aqueous-ammonia) for CS was developed to remove lignin, swell the biomass, and improve enzymatic digestibility. Based on the sugar yield during enzymatic hydrolysis, the optimal pretreatment conditions were 1 % NaOH+8 % NH(4)OH, 50°C, 48 h, with a solid-to-liquid ratio 1:10. The results demonstrated that soaking pretreatment removed 63.6 % lignin while reserving most of the carbohydrates. After enzymatic hydrolysis, the yields of glucose and xylose were 78.5 % and 69.3 %, respectively. The simultaneous saccharification and fermentation of pretreated CS using Pichia stipitis resulted in an ethanol concentration of 36.1 g/L, corresponding only to 63.3 % of the theoretical maximum. In order to simplify the process and reduce the capital cost, the liquid fraction of the pretreatment was used to re-soak new CS. For methane production, the re-soaked CS and the residues of SSF were anaerobically digested for 120 days. Fifteen grams CS were converted to 1.9 g of ethanol and 1337.3 mL of methane in the entire process.

  13. Bioethanol production from steam-pretreated corn stover through an isomerase mediated process.

    Science.gov (United States)

    De Bari, Isabella; Cuna, Daniela; Di Matteo, Vincenzo; Liuzzi, Federico

    2014-03-25

    Agricultural by-products such as corn stover are considered strategic raw materials for the production of second-generation bioethanol from renewable and non-food sources. This paper describes the conversion of steam-pretreated corn stover to ethanol utilising a multi-step process including enzymatic hydrolysis, isomerisation, and fermentation of mixed hydrolysates with native Saccharomyces cerevisiae. An immobilised isomerase enzyme was used for the xylose isomerisation along with high concentrations of S. cerevisiae. The objective was to assess the extent of simultaneity of the various conversion steps, through a detailed analysis of process time courses, and to test this process scheme for the conversion of lignocellulosic hydrolysates containing several inhibitors of the isomerase enzyme (e.g. metal ions, xylitol and glycerol). The process was tested on two types of hydrolysate after acid-catalysed steam pretreatment: (a) the water soluble fraction (WSF) in which xylose was the largest carbon source and (b) the entire slurry, containing both cellulose and hemicellulose carbohydrates, in which glucose predominated. The results indicated that the ethanol concentration rose when the inoculum concentration was increased in the range 10-75 g/L. However, when xylose was the largest carbon source, the metabolic yields were higher than 0.51g(ethanol)/g(consumed) sugars probably due to the use of yeast internal cellular resources. This phenomenon was not observed in the fermentation of mixed hydrolysates obtained from the entire pretreated product and in which glucose was the largest carbon source. The ethanol yield from biomass suspensions with dry matter (DM) concentrations of 11-12% (w/v) was 70% based on total sugars (glucose, xylose, galactose). The results suggest that xylulose uptake was more effective in mixed hydrolysates containing glucose levels similar to, or higher than, xylose. Analysis of the factors that limit isomerase activity in lignocellulosic

  14. Effect of pelleting process variables on physical properties and sugar yields of ammonia fiber expansion pretreated corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Amber N. Hoover; Jaya Shankar Tumuluru; Farzaneh Teymouri; Garold L. Gresham; Janette Moore

    2014-07-01

    Pelletization process variables including grind size (4, 6 mm), die speed (40, 50, 60 Hz), and preheating (none, 70 degrees C) were evaluated to understand their effect on pellet quality attributes and sugar yields of ammonia fiber expansion (AFEX) pretreated biomass. The bulk density of the pelletized AFEX corn stover was three to six times greater compared to untreated and AFEX-treated corn stover. Also the durability of the pelletized AFEX corn stover was >97.5% for all pelletization conditions studied except for preheated pellets. Die speed had no effect on enzymatic hydrolysis sugar yields of pellets. Pellets produced with preheating or a larger grind size (6 mm) had similar or lower sugar yields. Pellets generated with 4 mm AFEX-treated corn stover, a 60 Hz die speed, and no preheating resulted in pellets with similar or greater density, durability, and sugar yields compared to other pelletization conditions.

  15. Production of butanol (a biofuel) from agricultural residues: Part II - Use of corn stover and switchgrass hydrolysates

    Energy Technology Data Exchange (ETDEWEB)

    Qureshi, Nasib; Saha, Badal C.; Hector, Ronald E.; Dien, Bruce; Iten, Loren; Bowman, Michael J.; Cotta, Michael A. [United States Department of Agriculture (USDA), Agricultural Research Service (ARS), National Center for Agricultural Utilization Research (NCAUR), Bioenergy Research, 1815 N. University Street, Peoria, IL 61604 (United States); Hughes, Stephen; Liu, Siqing [USDA-ARS-NCAUR, Renewable Product Technology, 1815 N. University Street, Peoria, IL 61604 (United States); Sarath, Gautam [USDA-ARS, Grain, Forage, and Bioenergy Research Unit, University of Nebraska, 314 Biochemistry Hall, East Campus, Lincoln, NE 68583 (United States)

    2010-04-15

    Acetone butanol ethanol (ABE) was produced from hydrolysed corn stover and switchgrass using Clostridium beijerinckii P260. A control experiment using glucose resulted in the production of 21.06 g L{sup -1} total ABE. In this experiment an ABE yield and productivity of 0.41 and 0.31 g L{sup -1} h{sup -1} was achieved, respectively. Fermentation of untreated corn stover hydrolysate (CSH) exhibited no growth and no ABE production; however, upon dilution with water (two fold) and wheat straw hydrolysate (WSH, ratio 1:1), 16.00 and 18.04 g L{sup -1} ABE was produced, respectively. These experiments resulted in ABE productivity of 0.17-0.21 g L{sup -1} h{sup -1}. Inhibitors present in CSH were removed by treating the hydrolysate with Ca(OH){sub 2} (overliming). The culture was able to produce 26.27 g L{sup -1} ABE after inhibitor removal. Untreated switchgrass hydrolysate (SGH) was poorly fermented and the culture did not produce more than 1.48 g L{sup -1} ABE which was improved to 14.61 g L{sup -1}. It is suggested that biomass pretreatment methods that do not generate inhibitors be investigated. Alternately, cultures resistant to inhibitors and able to produce butanol at high concentrations may be another approach to improve the current process. (author)

  16. Residual stresses in material processing

    Science.gov (United States)

    Kozaczek, K. J.; Watkins, T. R.; Hubbard, C. R.; Wang, Xun-Li; Spooner, S.

    Material manufacturing processes often introduce residual stresses into the product. The residual stresses affect the properties of the material and often are detrimental. Therefore, the distribution and magnitude of residual stresses in the final product are usually an important factor in manufacturing process optimization or component life prediction. The present paper briefly discusses the causes of residual stresses. It then addresses the direct, nondestructive methods of residual stress measurement by X ray and neutron diffraction. Examples are presented to demonstrate the importance of residual stress measurement in machining and joining operations.

  17. Effect of pelleting process variables on physical properties and sugar yields of ammonia fiber expansion pretreated corn stover.

    Science.gov (United States)

    Hoover, Amber N; Tumuluru, Jaya Shankar; Teymouri, Farzaneh; Moore, Janette; Gresham, Garold

    2014-07-01

    Pelletization process variables, including grind size (4, 6mm), die speed (40, 50, 60 Hz), and preheating (none, 70°C), were evaluated to understand their effect on pellet quality attributes and sugar yields of ammonia fiber expansion (AFEX) pretreated biomass. The bulk density of the pelletized AFEX corn stover was three to six times greater compared to untreated and AFEX-treated corn stover. Also, the durability of the pelletized AFEX corn stover was>97.5% for all pelletization conditions studied except for preheated pellets. Die speed had no effect on enzymatic hydrolysis sugar yields of pellets. Pellets produced with preheating or a larger grind size (6mm) had similar or lower sugar yields. Pellets generated with 4mm AFEX-treated corn stover, a 60Hz die speed, and no preheating resulted in pellets with similar or greater density, durability, and sugar yields compared to other pelletization conditions. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Bioaugmentation for Electricity Generation from Corn Stover Biomass Using Microbial Fuel Cells

    KAUST Repository

    Wang, Xin

    2009-08-01

    Corn stover is usually treated by an energy-intensive or expensive process to extract sugars for bioenergy production. However, it is possible to directly generate electricity from corn stover in microbial fuel cells (MFCs) through the addition of microbial consortia specifically acclimated for biomass breakdown. A mixed culture that was developed to have a high saccharification rate with corn stover was added to singlechamber, air-cathode MFCs acclimated for power production using glucose. The MFC produced a maximum power of 331 mW/ m 2 with the bioaugmented mixed culture and corn stover, compared to 510 mW/m2 using glucose. Denaturing gradient gel electrophoresis (DGGE) showed the communities continued to evolve on both the anode and corn stover biomass over 60 days, with several bacteria identified including Rhodopseudomonas palustris. The use of residual solids from the steam exploded corn stover produced 8% more power (406 mW/m2) than the raw corn stover. These results show that it is possible to directly generate electricity from waste corn stover in MFCs through bioaugmentation using naturally occurring bacteria. © 2009 American Chemical Society.

  19. Process integration for simultaneous saccharification, fermentation, and recovery (SSFR): production of butanol from corn stover using Clostridium beijerinckii P260.

    Science.gov (United States)

    Qureshi, N; Singh, V; Liu, S; Ezeji, T C; Saha, B C; Cotta, M A

    2014-02-01

    A simultaneous saccharification, fermentation, and recovery (SSFR) process was developed for the production of acetone-butanol-ethanol (AB or ABE), of which butanol is the main product, from corn stover employing Clostridium beijerinckii P260. Of the 86 g L(-1) corn stover provided, over 97% of the sugars were released during hydrolysis and these were fermented completely with an ABE productivity of 0.34 g L(-1)h(-1) and yield of 0.39. This productivity is higher than 0.31 g L(-1)h(-1) when using glucose as a substrate demonstrating that AB could be produced efficiently from lignocellulosic biomass. Acetic acid that was released from the biomass during pretreatment and hydrolysis was also used by the culture to produce AB. An average rate of generation of sugars during corn stover hydrolysis was 0.98 g L(-1)h(-1). In this system AB was recovered using vacuum, and as a result of this (simultaneous product recovery), 100% sugars were used by the culture. Published by Elsevier Ltd.

  20. Solidification process for sludge residue

    International Nuclear Information System (INIS)

    Pearce, K.L.

    1998-01-01

    This report investigates the solidification process used at 100-N Basin to solidify the N Basin sediment and assesses the N Basin process for application to the K Basin sludge residue material. This report also includes a discussion of a solidification process for stabilizing filters. The solidified matrix must be compatible with the Environmental Remediation Disposal Facility acceptance criteria

  1. Conversion of residual organics in corn stover-derived biorefinery stream to bioenergy via microbial fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Borole, Abhijeet P [ORNL; Hamilton, Choo Yieng [ORNL; Schell, Daniel J [National Renewable Energy Laboratory (NREL)

    2012-01-01

    A biorefinery process typically uses about 4-10 times as much water as the amount of biofuel generated. The wastewater produced in a biorefinery process contains residual sugars, 5-furfural, phenolics, and other pretreatment and fermentation byproducts. Treatment of the wastewater can reduce the need for fresh water and potentially add to the environmental benefits of the process. Use of microbial fuel cells (MFCs) for conversion of the various organics present in a post-fermentation biorefinery stream is reported here. The organic loading was varied over a wide range to assess removal efficiency, coulombic efficiency and power production. A coulombic efficiency of 40% was observed for a low loading of 1% (0.66 g/L) and decreased to 1.8% for the undiluted process stream (66.4 g/L organic loading). A maximum power density of 1180 mW/m2 was observed at a loading of 8%. Excessive loading was found to result in poor electrogenic performance. The results indicate that operation of an MFC at an intermediate loading using dilution and recirculation of the process stream can enable effective treatment with bioenergy recovery.

  2. Process to recycle shredder residue

    Science.gov (United States)

    Jody, Bassam J.; Daniels, Edward J.; Bonsignore, Patrick V.

    2001-01-01

    A system and process for recycling shredder residue, in which separating any polyurethane foam materials are first separated. Then separate a fines fraction of less than about 1/4 inch leaving a plastics-rich fraction. Thereafter, the plastics rich fraction is sequentially contacted with a series of solvents beginning with one or more of hexane or an alcohol to remove automotive fluids; acetone to remove ABS; one or more of EDC, THF or a ketone having a boiling point of not greater than about 125.degree. C. to remove PVC; and one or more of xylene or toluene to remove polypropylene and polyethylene. The solvents are recovered and recycled.

  3. Process for measuring residual stresses

    International Nuclear Information System (INIS)

    Elfinger, F.X.; Peiter, A.; Theiner, W.A.; Stuecker, E.

    1982-01-01

    No single process can at present solve all problems. The complete destructive processes only have a limited field of application, as the component cannot be reused. However, they are essential for the basic determination of stress distributions in the field of research and development. Destructive and non-destructive processes are mainly used if investigations have to be carried out on original components. With increasing component size, the part of destructive tests becomes smaller. The main applications are: quality assurance, testing of manufactured parts and characteristics of components. Among the non-destructive test procedures, X-raying has been developed most. It gives residual stresses on the surface and on surface layers near the edges. Further development is desirable - in assessment - in measuring techniques. Ultrasonic and magnetic crack detection processes are at present mainly used in research and development, and also in quality assurance. Because of the variable depth of penetration and the possibility of automation they are gaining in importance. (orig./RW) [de

  4. Process Design Report for Stover Feedstock: Lignocellulosic Biomass to Ethanol Process Design and Economics Utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydrolysis for Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Aden, A. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ruth, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ibsen, K. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jechura, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Neeves, K. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sheehan, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Wallace, B. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Montague, L. [Harris Group, Seattle, WA (United States); Slayton, A. [Harris Group, Seattle, WA (United States); Lukas, J. [Harris Group, Seattle, WA (United States)

    2002-06-01

    The U.S. Department of Energy (DOE) is promoting the development of ethanol from lignocellulosic feedstocks as an alternative to conventional petroleum-based transportation fuels. DOE funds both fundamental and applied research in this area and needs a method for predicting cost benefits of many research proposals. To that end, the National Renewable Energy Laboratory (NREL) has modeled many potential process designs and estimated the economics of each process during the last 20 years. This report is an update of the ongoing process design and economic analyses at NREL.

  5. Decomposition and Fertilizing Effects of Maize Stover and ...

    African Journals Online (AJOL)

    Mixing of maize stover and C. odorata residues improved the nutrient content as well as nutrient release by the mixtures resulting in greater maize grain yields in the mixtures than the sole maize stover treatment. It is recommended that C. odorata be used as green manure, mulching or composting material to improve soil ...

  6. Residual analysis for spatial point processes

    DEFF Research Database (Denmark)

    Baddeley, A.; Turner, R.; Møller, Jesper

    process. Residuals are ascribed to locations in the empty background, as well as to data points of the point pattern. We obtain variance formulae, and study standardised residuals. There is also an analogy between our spatial residuals and the usual residuals for (non-spatial) generalised linear models...... or covariate effects. Q-Q plots of the residuals are effective in diagnosing interpoint interaction. Some existing ad hoc statistics of point patterns (quadrat counts, scan statistic, kernel smoothed intensity, Berman's diagnostic) are recovered as special cases....

  7. Effect of process variables on the density and durability of the pellets made from high moisture corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Jaya Shankar Tumuluru

    2014-03-01

    A flat die pellet mill was used to understand the effect of high levels of feedstock moisture content in the range of 28–38% (w.b.), with die rotational speeds of 40–60 Hz, and preheating temperatures of 30–110 °C on the pelleting characteristics of 4.8 mm screen size ground corn stover using an 8 mm pellet die. The physical properties of the pelletised biomass studied are: (a) pellet moisture content, (b) unit, bulk and tapped density, and (c) durability. Pelletisation experiments were conducted based on central composite design. Analysis of variance (ANOVA) indicated that feedstock moisture content influenced all of the physical properties at P < 0.001. Pellet moisture content decreased with increase in preheating temperature to about 110 °C and decreasing the feedstock moisture content to about 28% (w.b.). Response surface models developed for quality attributes with respect to process variables has adequately described the process with coefficient of determination (R2) values of >0.88. The other pellet quality attributes such as unit, bulk, tapped density, were maximised at feedstock moisture content of 30–33% (w.b.), die speeds of >50 Hz and preheating temperature of >90 °C. In case of durability a medium moisture content of 33–34% (w.b.) and preheating temperatures of >70 °C and higher die speeds >50 Hz resulted in high durable pellets. It can be concluded from the present study that feedstock moisture content, followed by preheating, and die rotational speed are the interacting process variables influencing pellet moisture content, unit, bulk and tapped density and durability.

  8. Properties of residuals for spatial point processes

    DEFF Research Database (Denmark)

    Baddeley, A.; Møller, Jesper; Pakes, A. G.

    2008-01-01

    For any point process in Rd that has a Papangelou conditional intensity λ, we define a random measure of ‘innovations' which has mean zero. When the point process model parameters are estimated from data, there is an analogous random measure of ‘residuals'. We analyse properties of the innovation...... and residuals, including first and second moments, conditional independence, a martingale property, and lack of correlation. Some large sample asymptotics are studied. We derive the marginal distribution of smoothed residuals by solving a distributional equivalence....

  9. Thermal Adsorption Processing Of Hydrocarbon Residues

    Directory of Open Access Journals (Sweden)

    Sudad H. Al.

    2017-04-01

    Full Text Available The raw materials of secondary catalytic processes must be pre-refined. Among these refining processes are the deasphalting and demetallization including their thermo adsorption or thermo-contact adsorption variety. In oil processing four main processes of thermo-adsorption refining of hydrocarbon residues are used ART Asphalt Residual Treating - residues deasphaltizing 3D Discriminatory Destructive Distillation developed in the US ACT Adsorption-Contact Treatment and ETCC Express Thermo-Contact Cracking developed in Russia. ART and ACT are processes with absorbers of lift type reactor while 3D and ETCC processes are with an adsorbing reactor having ultra-short contact time of the raw material with the adsorbent. In all these processes refining of hydrocarbon residues is achieved by partial Thermo-destructive transformations of hydrocarbons and hetero-atomic compounds with simultaneous adsorption of the formed on the surface of the adsorbents resins asphaltene and carboids as well as metal- sulphur - and nitro-organic compounds. Demetallized and deasphalted light and heavy gas oils or their mixtures are a quality raw material for secondary deepening refining processes catalytic and hydrogenation cracking etc. since they are characterized by low coking ability and low content of organometallic compounds that lead to irreversible deactivation of the catalysts of these deepening processes.

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

    Science.gov (United States)

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

    2014-09-01

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

  11. Efficient production of bioethanol from corn stover by pretreatment with a combination of sulfuric acid and sodium hydroxide.

    Science.gov (United States)

    Tan, Li; Tang, Yue-Qin; Nishimura, Hiroto; Takei, Shouta; Morimura, Shigeru; Kida, Kenji

    2013-01-01

    Corn stover is the most abundant agricultural residue in China and a valuable reservoir for bioethanol production. In this study, we proposed a process for producing bioethanol from corn stover; the pretreatment prior to presaccharification, followed by simultaneous saccharification and fermentation (SSF) by using a flocculating Saccharomyces cerevisiae strain, was optimized. Pretreatment with acid-alkali combination (1% H2SO4, 150 °C, 10 min, followed by 1% NaOH, 80°C, 60 min) resulted in efficient lignin removal and excellent recovery of xylose and glucose. A glucose recovery efficiency of 92.3% was obtained by enzymatic saccharification, when the pretreated solid load was 15%. SSF was carried out at 35 °C for 36 hr after presaccharification at 50 °C for 24 hr, and an ethanol yield of 88.2% was achieved at a solid load of 15% and an enzyme dosage of 15 FPU/g pretreated corn stover.

  12. A two-stage pretreatment process using dilute hydrochloric acid followed by Fenton oxidation to improve sugar recovery from corn stover.

    Science.gov (United States)

    Li, Wenzhi; Liu, Qiyu; Ma, Qiaozhi; Zhang, Tingwei; Ma, Longlong; Jameel, Hasan; Chang, Hou-Min

    2016-11-01

    A two-stage pretreatment process is proposed in this research in order to improve sugar recovery from corn stover. In the proposed process, corn stover is hydrolyzed by dilute hydrochloric acid to recover xylose, which is followed by a Fenton reagent oxidation to remove lignin. 0.7wt% dilute hydrochloric acid is applied in the first stage pretreatment at 120°C for 40min, resulting in 81.0% xylose removal. Fenton reagent oxidation (1g/L FeSO4·7H2O and 30g/L H2O2) is performed at room temperature (about 20°C) for 12 has a second stage which resulted in 32.9% lignin removal. The glucose yield in the subsequent enzymatic hydrolysis was 71.3% with a very low cellulase dosage (3FPU/g). This two-stage pretreatment is effective due to the hydrolysis of hemicelluloses in the first stage and the removal of lignin in the second stage, resulting in a very high sugar recovery with a low enzyme loading. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Production and characterization of cellulose nanofibril (CNF) from agricultural waste corn stover

    Science.gov (United States)

    Corn stover, as an agricultural waste, has little economic value. The value-added product cellulose was prepared from corn stover by a relatively simple two-stage process - alkali treatment and bleaching resulting in a >93% purity. The particle size of the corn stover cellulose was reduced by mechan...

  14. The plasma hearth process: Process residuals characterization

    International Nuclear Information System (INIS)

    Leatherman, G.L.; Geimer, R.; Batdorf, J.; Hassel, G.; Wolfe, P.; Carney, K.P.

    1994-01-01

    The Plasma Hearth Process (PHP) is a high-temperature waste treatment process being developed by Science Applications International Corporation (SAIC) for the Department of Energy (DOE) that destroys hazardous organics while stabilizing radionuclides and hazardous metals in a vitreous slag waste form. The PHP has potential application for the treatment of a wide range of mixed waste types in both the low-level and transuranic (TRU) mixed waste categories. DOE, through the Office of Technology Development's Mixed Waste Integrated Program (MWIP) is conducting a three phase development project to ready the PHP for implementation in the DOE complex

  15. Reclamation of plutonium from pyrochemical processing residues

    International Nuclear Information System (INIS)

    Gray, L.W.; Gray, J.H.; Holcomb, H.P.; Chostner, D.F.

    1987-04-01

    Savannah River Laboratory (SRL), Savannah River Plant (SRP), and Rocky Flats Plant (RFP) have jointly developed a process to recover plutonium from molten salt extraction residues. These NaCl, KCL, and MgCl 2 residues, which are generated in the pyrochemical extraction of 241 Am from aged plutonium metal, contain up to 25 wt % dissolved plutonium and up to 2 wt % americium. The overall objective was to develop a process to convert these residues to a pure plutonium metal product and discardable waste. To meet this objective a combination of pyrochemical and aqueous unit operations was used. The first step was to scrub the salt residue with a molten metal (aluminum and magnesium) to form a heterogeneous ''scrub alloy'' containing nominally 25 wt % plutonium. This unit operation, performed at RFP, effectively separated the actinides from the bulk of the chloride salts. After packaging in aluminum cans, the ''scrub alloy'' was then dissolved in a nitric acid - hydrofluoric acid - mercuric nitrate solution at SRP. Residual chloride was separated from the dissolver solution by precipitation with Hg 2 (NO 3 ) 2 followed by centrifuging. Plutonium was then separated from the aluminum, americium and magnesium using the Purex solvent extraction system. The 241 Am was diverted to the waste tank farm, but could be recovered if desired

  16. Properties of residuals for spatial point processes

    DEFF Research Database (Denmark)

    Baddeley, A.; Møller, Jesper; Pakes, A.G.

    For any point process in $R^d$ that has a Papangelou conditional intensity $lambda$, we define a random measure of ‘innovations’ which has mean zero. When the point process model parameters are estimated from data, there is an analogous random measure of ‘residuals’. We analyse properties of the ...... of the innovations and residuals, including first and second moments, conditional independence, a martingale property, lack of correlation, and marginal distributions....

  17. Lignocellulosic Biomass to Ethanol Process Design and Economics Utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydrolysis for Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Aden, A.; Ruth, M.; Ibsen, K.; Jechura, J.; Neeves, K.; Sheehan, J.; Wallace, B.; Montague, L.; Slayton, A.; Lukas, J.

    2002-06-01

    and costing for the lignin combustor and boiler turbogenerator was reviewed by Reaction Engineering Inc. (REI) and Merrick & Company reviewed the wastewater treatment. Since then, NREL has engaged Harris Group (Harris) to perform vendor testing, process design, and costing of critical equipment identified during earlier work. This included solid/liquid separation and pretreatment reactor design and costing. Corn stover handling was also investigated to support DOE's decision to focus on corn stover as a feedstock for lignocellulosic ethanol. Working with Harris, process design and costing for these areas were improved through vendor designs, costing, and vendor testing in some cases. In addition to this work, enzyme costs were adjusted to reflect collaborative work between NREL and enzyme manufacturers (Genencor International and Novozymes Biotech) to provide a delivered enzyme for lignocellulosic feedstocks. This report is the culmination of our work and represents an updated process design and cost basis for the process using a corn stover feedstock. The process design and economic model are useful for predicting the cost benefits of proposed research. Proposed research results can be translated into modifications of the process design, and the economic impact can be assessed. This allows DOE, NREL, and other researchers to set priorities on future research with an understanding of potential reductions to the ethanol production cost. To be economically viable, ethanol production costs must be below market values for ethanol. DOE has chosen a target ethanol selling price of $1.07 per gallon as a goal for 2010. The conceptual design and costs presented here are based on a 2010 plant start-up date. The key research targets required to achieve this design and the $1.07 value are discussed in the report.

  18. Alkaline Peroxide Delignification of Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Mittal, Ashutosh [Biosciences; Katahira, Rui [National; Donohoe, Bryon S. [Biosciences; Black, Brenna A. [National; Pattathil, Sivakumar [Complex; Stringer, Jack M. [National; Beckham, Gregg T. [National

    2017-05-30

    Selective biomass fractionation into carbohydrates and lignin is a key challenge in the conversion of lignocellulosic biomass to fuels and chemicals. In the present study, alkaline hydrogen peroxide (AHP) pretreatment was investigated to fractionate lignin from polysaccharides in corn stover (CS), with a particular emphasis on the fate of the lignin for subsequent valorization. The influence of peroxide loading on delignification during AHP pretreatment was examined over the range of 30-500 mg H2O2/g dry CS at 50 degrees C for 3 h. Mass balances were conducted on the solid and liquid fractions generated after pretreatment for each of the three primary components, lignin, hemicellulose, and cellulose. AHP pretreatment at 250 mg H2O2/g dry CS resulted in the pretreated solids with more than 80% delignification consequently enriching the carbohydrate fraction to >90%. Two-dimensional nuclear magnetic resonance (2D-NMR) spectroscopy of the AHP pretreated residue shows that, under high peroxide loadings (>250 mg H2O2/g dry CS), most of the side chain structures were oxidized and the aryl-ether bonds in lignin were partially cleaved, resulting in significant delignification of the pretreated residues. Gel permeation chromatography (GPC) analysis shows that AHP pretreatment effectively depolymerizes CS lignin into low molecular weight (LMW) lignin fragments in the aqueous fraction. Imaging of AHP pretreated residues shows a more granular texture and a clear lamellar pattern in secondary walls, indicative of layers of varying lignin removal or relocalization. Enzymatic hydrolysis of this pretreated residue at 20 mg/g of glucan resulted in 90% and 80% yields of glucose and xylose, respectively, after 120 h. Overall, AHP pretreatment is able to selectively remove more than 80% of the lignin from biomass in a form that has potential for downstream valorization processes and enriches the solid pulp into a highly digestible material.

  19. Current and potential U.S. Corn Stover Supplies

    Energy Technology Data Exchange (ETDEWEB)

    Graham, Robin Lambert [ORNL; Nelson, R [Kansas State University; Perlack, Robert D [ORNL; Sheehan, J. [National Renewable Energy Laboratory (NREL); Wright, Lynn L [subcontractor

    2007-01-01

    Agricultural residues such as corn (Zea mays L.) stover are a potential feedstock for bioenergy and bio-based products that could reduceU.S. dependence on foreign oil. Collection of such residues must take into account concerns that residue removal could increase erosion, reduce crop productivity, and deplete soil carbon and nutrients. This article estimates where and how much corn stover can be collected sustainably in the USA using existing commercial equipment and estimates costs of that collection. Erosion constraints to collection were considered explicitly, and crop productivity and soil nutrient constraints were considered implicitly, by recognizing the value of residues for maintaining soil moisture and including the cost of fertilizer to replace nutrients removed. Possible soil carbon loss was not considered in the analysis. With an annual production of 196 million Mg of corn grain (about9.2 billion bushels), the USA produces 196 million Mg of stover. Under current rotation and tillage practices, about 30% of this stover could be collected for less than $33 per Mg, taking into consideration erosion and soil moisture concerns and nutrient replacement costs. Wind erosion is a major constraint to stover collection. Analysis suggests three regions of the country (central Illinois, northern Iowa/southern Minnesota, and along the Platte River in Nebraska) produce sufficient stover to support large biorefineries with one million Mg per year feedstock demands and that if farmers converted to universal no-till production of corn, then over 100 million Mg of stover could be collected annually without causing erosion to exceed the tolerable soil loss.

  20. BIOFUEL FROM CORN STOVER

    Directory of Open Access Journals (Sweden)

    Ljiljanka Tomerlin

    2003-12-01

    Full Text Available This paper deals with production of ethyl alcohol (biofuel from corn stover acid hydrolysate by yeasts, respectively at Pichia stipitis y-7124 and Pachysolen tannophilus y-2460 and Candida shehatae y-12856. Since moist corn stover (Hybryds 619 is proving to decomposition by phyllospheric microflora. It was (conserved spattered individually by microbicids: Busan-90, Izosan-G and formalin. In form of prismatic bales, it was left in the open air during 6 months (Octobar - March. At the beginning and after 6 months the microbiological control was carried out. The only one unspattered (control and three stover corn bals being individually spattered by microbicids were fragmented and cooked with sulfur acid. The obtained four acid hydrolysates are complex substratums, containing, apart from the sugars (about 11 g dm-3 pentosa and about 5.4 g dm-3 hexose, decomposite components as lignin, caramel sugars and uronic acids. By controlling the activity of the mentioned yeasts it was confirmed that yeasts Pichia stipitis y-7124 obtained best capability of ethyl alcohol production from corn stover acid hydrolysate at 0.23 vol. % to 0.49 vol. %.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-03-01

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

  2. Biomechanics of Wheat/Barley Straw and Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Christopher T. Wright; Peter A. Pryfogle; Nathan A. Stevens; Eric D. Steffler; J. Richard Hess; Thomas H. Ulrich

    2005-03-01

    The lack of understanding of the mechanical characteristics of cellulosic feedstocks is a limiting factor in economically collecting and processing crop residues, primarily wheat and barley stems and corn stover. Several testing methods, including compression, tension, and bend have been investigated to increase our understanding of the biomechanical behavior of cellulosic feedstocks. Biomechanical data from these tests can provide required input to numerical models and help advance harvesting, handling, and processing techniques. In addition, integrating the models with the complete data set from this study can identify potential tools for manipulating the biomechanical properties of plant varieties in such a manner as to optimize their physical characteristics to produce higher value biomass and more energy efficient harvesting practices.

  3. Total environmental impacts of biofuels from corn stover using a hybrid life cycle assessment model combining process life cycle assessment and economic input-output life cycle assessment.

    Science.gov (United States)

    Liu, Changqi; Huang, Yaji; Wang, Xinye; Tai, Yang; Liu, Lingqin; Liu, Hao

    2018-01-01

    Studies on the environmental analysis of biofuels by fast pyrolysis and hydroprocessing (BFPH) have so far focused only on the environmental impacts from direct emissions and have included few indirect emissions. The influence of ignoring some indirect emissions on the environmental performance of BFPH has not been well investigated and hence is not really understood. In addition, in order to avoid shifting environmental problems from one medium to another, a comprehensive assessment of environmental impacts caused by the processes must quantify the environmental emissions to all media (air, water, and land) in relation to each life cycle stage. A well-to-wheels assessment of the total environmental impacts resulting from direct emissions and indirect emissions of a BFPH system with corn stover is conducted using a hybrid life cycle assessment (LCA) model combining the economic input-output LCA and the process LCA. The Tool for the Reduction and Assessment of Chemical and other environmental Impacts (TRACI) has been used to estimate the environmental impacts in terms of acidification, eutrophication, global climate change, ozone depletion, human health criteria, photochemical smog formation, ecotoxicity, human health cancer, and human health noncancer caused by 1 MJ biofuel production. Taking account of all the indirect greenhouse gas (GHG) emissions, the net GHG emissions (81.8 g CO 2 eq/MJ) of the biofuels are still less than those of petroleum-based fuels (94 g CO 2 eq/MJ). Maize production and pyrolysis and hydroprocessing make major contributions to all impact categories except the human health criteria. All impact categories resulting from indirect emissions except eutrophication and smog air make more than 24% contribution to the total environmental impacts. Therefore, the indirect emissions are important and cannot be ignored. Sensitivity analysis has shown that corn stover yield and bio-oil yield affect the total environmental impacts of the biofuels

  4. Decomposition and fertilizing effects of maize stover and chromolaena odorata on maize yield

    International Nuclear Information System (INIS)

    Tetteh, F.M.; Safo, E.Y.; Quansah, C.

    2008-01-01

    The quality, rates of decomposition and the fertilizing effect of chromolaena odorata, and maize stover were determined in field experiments as surface application or buried in litter bags. Studies on the effect of plant materials of contrasting qualities (maize stover and C. odorata) applied sole (10 Mg ha -1 ) and mixed, on maize grain and biomass yield were also conducted on the Asuansi (Ferric Acrisol) soil series. Total nitrogen content of the residues ranged from 0.85% in maize stover to 3.50% in C. odorata. Organic carbon ranged from 34.90% in C. odorata to 48.50% in maize stover. Phosphorus ranged from 0.10% in maize stover to 0.76% in C. odorata. In the wet season, the decomposition rate constants (k) were 0.0319 day -1 for C. odorata, and 0.0081 for maize stover. In the dry season, the k values were 0.0083 for C. odorata, and 0.0072 day -1 for maize stover. Burying of the plant materials reduced the half-life (t 50 ) periods from 18 to 10 days for C. odorata, and 45 to 20 days for maize stover. Maize grain yield of 2556 kg ha -1 was obtained in sole C. odorata (10 Mg ha -1 ) compared with 2167 kg ha -1 for maize stover. Mixing of maize stover and C. odorata residues improved the nutrient content as well as nutrient release by the mixtures resulting in greater maize grain yields in the mixtures than the sole maize stover treatment. It is recommended that C. odorata be used as green manure, mulching or composting material to improve fertility. (au)

  5. Characteristics of corn stover pretreated with liquid hot water and fed-batch semi-simultaneous saccharification and fermentation for bioethanol production.

    Science.gov (United States)

    Li, Xuezhi; Lu, Jie; Zhao, Jian; Qu, Yinbo

    2014-01-01

    Corn stover is a promising feedstock for bioethanol production because of its abundant availability in China. To obtain higher ethanol concentration and higher ethanol yield, liquid hot water (LHW) pretreatment and fed-batch semi-simultaneous saccharification and fermentation (S-SSF) were used to enhance the enzymatic digestibility of corn stover and improve bioconversion of cellulose to ethanol. The results show that solid residues from LHW pretreatment of corn stover can be effectively converted into ethanol at severity factors ranging from 3.95 to 4.54, and the highest amount of xylan removed was approximately 89%. The ethanol concentrations of 38.4 g/L and 39.4 g/L as well as ethanol yields of 78.6% and 79.7% at severity factors of 3.95 and 4.54, respectively, were obtained by fed-batch S-SSF in an optimum conditions (initial substrate consistency of 10%, and 6.1% solid residues added into system at the prehydrolysis time of 6 h). The changes in surface morphological structure, specific surface area, pore volume and diameter of corn stover subjected to LHW process were also analyzed for interpreting the possible improvement mechanism.

  6. Characteristics of corn stover pretreated with liquid hot water and fed-batch semi-simultaneous saccharification and fermentation for bioethanol production.

    Directory of Open Access Journals (Sweden)

    Xuezhi Li

    Full Text Available Corn stover is a promising feedstock for bioethanol production because of its abundant availability in China. To obtain higher ethanol concentration and higher ethanol yield, liquid hot water (LHW pretreatment and fed-batch semi-simultaneous saccharification and fermentation (S-SSF were used to enhance the enzymatic digestibility of corn stover and improve bioconversion of cellulose to ethanol. The results show that solid residues from LHW pretreatment of corn stover can be effectively converted into ethanol at severity factors ranging from 3.95 to 4.54, and the highest amount of xylan removed was approximately 89%. The ethanol concentrations of 38.4 g/L and 39.4 g/L as well as ethanol yields of 78.6% and 79.7% at severity factors of 3.95 and 4.54, respectively, were obtained by fed-batch S-SSF in an optimum conditions (initial substrate consistency of 10%, and 6.1% solid residues added into system at the prehydrolysis time of 6 h. The changes in surface morphological structure, specific surface area, pore volume and diameter of corn stover subjected to LHW process were also analyzed for interpreting the possible improvement mechanism.

  7. Gold processing residue from Jacobina Basin: chemical and physical properties

    OpenAIRE

    Lima, Luiz Rogério Pinho de Andrade; Bernardez, Letícia Alonso; Barbosa, Luís Alberto Dantas

    2007-01-01

    p. 848-852 Gold processing residues or tailings are found in several areas in the Itapicuru River region (Bahia, Brazil), and previous studies indicated significant heavy metals content in the river sediments. The present work focused on an artisanal gold processing residue found in a site from this region. Samples were taken from the processing residue heaps and used to perform a physical and chemical characterization study using X-ray diffraction, scanning electron microscopy, neutron...

  8. Environmental and economic trade-offs in a watershed when using corn stover for bioenergy.

    Science.gov (United States)

    Gramig, Benjamin M; Reeling, Carson J; Cibin, Raj; Chaubey, Indrajeet

    2013-02-19

    There is an abundant supply of corn stover in the United States that remains after grain is harvested which could be used to produce cellulosic biofuels mandated by the current Renewable Fuel Standard (RFS). This research integrates the Soil Water Assessment Tool (SWAT) watershed model and the DayCent biogeochemical model to investigate water quality and soil greenhouse gas flux that results when corn stover is collected at two different rates from corn-soybean and continuous corn crop rotations with and without tillage. Multiobjective watershed-scale optimizations are performed for individual pollutant-cost minimization criteria based on the economic cost of each cropping practice and (individually) the effect on nitrate, total phosphorus, sediment, or global warming potential. We compare these results with a purely economic optimization that maximizes stover production at the lowest cost without taking environmental impacts into account. We illustrate trade-offs between cost and different environmental performance criteria, assuming that nutrients contained in any stover collected must be replaced. The key finding is that stover collection using the practices modeled results in increased contributions to atmospheric greenhouse gases while reducing nitrate and total phosphorus loading to the watershed relative to the status quo without stover collection. Stover collection increases sediment loading to waterways relative to when no stover is removed for each crop rotation-tillage practice combination considered; no-till in combination with stover collection reduced sediment loading below baseline conditions without stover collection. Our results suggest that additional information is needed about (i) the level of nutrient replacement required to maintain grain yields and (ii) cost-effective management practices capable of reducing soil erosion when crop residues are removed in order to avoid contributions to climate change and water quality impairments as a result

  9. Slipping processes in residual badlands reliefs

    Science.gov (United States)

    Díaz-Hernández, Jose Luis; Yepes, Jorge

    2010-05-01

    We define slips as structures developed by more or less saturated colloidal suspension that slide down the walls of residual reliefs found in badlands. These suspensions seem to originate in the soils crowning gully reliefs and also from rainwater dripping onto the walls of poorly cemented sediments such as siltstone. We call this process slipping and the resulting morphologies represent a group of minor badlands forms, often linked to piping and fluting. Slipping occurs according to the following sequence of forms: 1. Mud droplets. These are irregular linear structures caused by mud droplets sliding down sub-vertical walls. The droplet is usually found at the end of a small channel. These morphologies represent the course of the sliding droplets that become fossilized and not the impact of the droplets on the sediment. 2. Slips sensu stricto. These are uninterrupted surface structures covering sub-vertical walls to a greater or lesser extent. The thickness of this type of covering varies from a few millimetres to 5cm. The inner structure of the slips consists of small laminas (» 100mm) and on the exterior they often present drip channels. A special case of these forms is butterfly structures, which appear in isolation, with repetitive patterns and the appearance of a winged insect stuck to the wall. 3. Pseudo-stalactites. These are free-standing conical regrowths with some similarity to stalactites in a karst cave. They occur when slips grow to over 5cm thick. The growth of these forms is similar to that of slips, with external superposition of fine, concentric layers with no central pore. A variety of these pseudo-stalactites are nodulous stalactites whose genesis is unknown. In this context, we should mention the existence of occasional stalagmites. In other cases, curtains of pseudo-stalactites can be found where these patterns are repeated finely. A more evolved stage of this form is the coalescence of pseudo-stalactites, representing a massive advance of

  10. Spring harvest of corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Lizotte, P.L. [Laval Univ., Quebec City, PQ (Canada). Dept. des sols et de genie agroalimentaire; Savoie, P. [Agriculture and Agri-Food Canada, Quebec City, PQ (Canada)

    2010-07-01

    Corn stover is typically left behind in the field after grain harvest. Although part of the stover should remain in the field for soil organic matter renewal and erosion protection, half of the stover could be removed sustainably. This represents about one million t dry matter (DM) of stover per year in the province of Quebec. Stover harvested in the fall is very wet. While there are applications for wet stover, the available markets currently require a dry product. Preliminary measurements have shown that stover left in the field throughout the winter becomes very dry, and a considerable amount would still be harvestable in the spring. In the spring of 2009, corn stover was harvested at 2 sites, each subdivided into 2 parcels. The first parcel was cut and raked in the fall of 2008 (fall parcel), while the second parcel was cut and raked in spring 2009. Fibre from both parcels was baled in the spring 2009. At the first site, a large square baler was used in late April to produce bales measuring 0.8 m x 0.9 m x 1.8 m. On the second site a round baler was used in late May to produce bales of 1.2 m in width by 1.45 m in diameter. On the second site, a small square baler was also used to produce bales of 0.35 m x 0.45 m x 0.60 m (spring cutting only). With the large square baler, an average of 3.9 t DM/ha was harvested equally on the fall parcel and the spring parcel, representing a 48 per cent recovery of biomass based on stover yields.

  11. Agronomic impacts of production scale harvesting of corn stover for cellulosic ethanol production in Central Iowa

    Science.gov (United States)

    Schau, Dustin

    This thesis investigates the impacts of corn stover harvest in Central Iowa with regards to nutrient removal, grain yield impacts and soil tilth. Focusing on phosphorus and potassium removal due to production of large, square bales of corn stover, 3.7 lb P2O5 and 18.7 lb K 2O per ton of corn stover were removed in 2011. P2O 5 removal remained statistically the same in 2012, but K2O decreased to 15.1 lb per ton of corn stover. Grain cart data showed no statistical difference in grain yield between harvest treatments, but yield monitor data showed a 3 - 17 bu/ac increase in 2012 and hand samples showed a 4 - 21 bu/ac increase in 2013. Corn stover residue levels decreased below 30% coverage when corn stover was harvested the previous fall and conventional tillage methods were used, but incorporating reduced tillage practices following corn stover harvest increased residue levels back up to 30% coverage. Corn emergence rates increased by at least 2,470 more plants per acre within the first three days of spiking, but final populations between harvest and nonharvest corn stover treatments were the same. Inorganic soil nitrogen in the form of ammonium and nitrate were not directly impacted by corn stover harvest, but it is hypothesized that weather patterns had a greater impact on nitrogen availability. Lastly, soil organic matter did not statistically change from 2011 to 2013 due to corn stover removal, even when analyzed within single soil types.

  12. Inclusion of calcium hydroxide-treated corn stover as a partial forage replacement in diets for lactating dairy cows.

    Science.gov (United States)

    Casperson, Brittany A; Wertz-Lutz, Aimee E; Dunn, Jim L; Donkin, Shawn S

    2018-03-01

    Chemical treatment may improve the nutritional value of corn crop residues, commonly referred to as corn stover, and the potential use of this feed resource for ruminants, including lactating dairy cows. The objective of this study was to determine the effect of prestorage chopping, hydration, and treatment of corn stover with Ca(OH) 2 on the feeding value for milk production, milk composition, and dry matter intake (DMI). Multiparous mid-lactation Holstein cows (n = 30) were stratified by parity and milk production and randomly assigned to 1 of 3 diets. Corn stover was chopped, hydrated, and treated with 6% Ca(OH) 2 (as-fed basis) and stored in horizontal silo bags. Cows received a control (CON) total mixed ration (TMR) or a TMR in which a mixture of treated corn stover and distillers grains replaced either alfalfa haylage (AHsub) or alfalfa haylage and an additional portion of corn silage (AH+CSsub). Treated corn stover was fed in a TMR at 0, 15, and 30% of the diet DM for the CON, AHsub, and AH+CSsub diets, respectively. Cows were individually fed in tiestalls for 10 wk. Milk production was not altered by treatment. Compared with the CON diet, DMI was reduced when the AHsub diet was fed and tended to be reduced when cows were fed the AH+CSsub diet (25.9, 22.7, and 23.1 ± 0.88 kg/d for CON, AHsub, and AH+CSsub diets, respectively). Energy-corrected milk production per unit of DMI (kg/kg) tended to increase with treated corn stover feeding. Milk composition, energy-corrected milk production, and energy-corrected milk per unit of DMI (kg/kg) were not different among treatments for the 10-wk feeding period. Cows fed the AHsub and AH+CSsub diets had consistent DMI over the 10-wk treatment period, whereas DMI for cows fed the CON diet increased slightly over time. Milk production was not affected by the duration of feeding. These data indicate that corn stover processing, prestorage hydration, and treatment with calcium hydroxide can serve as an alternative to

  13. Conversion of direct process high-boiling residue to monosilanes

    Science.gov (United States)

    Brinson, Jonathan Ashley; Crum, Bruce Robert; Jarvis, Jr., Robert Frank

    2000-01-01

    A process for the production of monosilanes from the high-boiling residue resulting from the reaction of hydrogen chloride with silicon metalloid in a process typically referred to as the "direct process." The process comprises contacting a high-boiling residue resulting from the reaction of hydrogen chloride and silicon metalloid, with hydrogen gas in the presence of a catalytic amount of aluminum trichloride effective in promoting conversion of the high-boiling residue to monosilanes. The present process results in conversion of the high-boiling residue to monosilanes. At least a portion of the aluminum trichloride catalyst required for conduct of the process may be formed in situ during conduct of the direct process and isolation of the high-boiling residue.

  14. Alkali activation processes for incinerator residues management.

    Science.gov (United States)

    Lancellotti, Isabella; Ponzoni, Chiara; Barbieri, Luisa; Leonelli, Cristina

    2013-08-01

    Incinerator bottom ash (BA) is produced in large amount worldwide and in Italy, where 5.1 millionstons of municipal solid residues have been incinerated in 2010, corresponding to 1.2-1.5 millionstons of produced bottom ash. This residue has been used in the present study for producing dense geopolymers containing high percentage (50-70 wt%) of ash. The amount of potentially reactive aluminosilicate fraction in the ash has been determined by means of test in NaOH. The final properties of geopolymers prepared with or without taking into account this reactive fraction have been compared. The results showed that due to the presence of both amorphous and crystalline fractions with a different degree of reactivity, the incinerator BA geopolymers exhibit significant differences in terms of Si/Al ratio and microstructure when reactive fraction is considered. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Effects of compositional changes of AFEX-treated and H-AFEX-treated corn stover on enzymatic digestibility.

    Science.gov (United States)

    Zhao, Chao; Ding, Weimin; Chen, Feng; Cheng, Cheng; Shao, Qianjun

    2014-03-01

    Corn stover is one of the main agricultural residues being considered as a cellulosic ethanol feedstock. This work evaluated the effectiveness of AFEX™(1) pretreatment for converting corn stover to fermentable sugars, both with and without pre-soaking in hydrogen peroxide. The compositional changes and enzymatic digestibility of AFEX-treated and H-AFEX-treated biomass were investigated. Results showed that most of the polysaccharides remained intact following each of these two methods. Compared with AFEX pretreatment, the H-AFEX process enhanced delignification and enzymatic hydrolysis yields of both glucose and xylose. The maximum glucan and xylan digestibility of H-AFEX process were 87.78% and 90.64%, respectively, and were obtained using 0.7 (w/w) water loading, 1.0 (w/w) ammonia loading, 0.5 (w/w) 30wt.% hydrogen peroxide loading, and 130°C for 10min. The results of the present work show that H-AFEX is a feasible pretreatment to improve the enzymatic saccharification of corn stover for bioethanol production. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Moisture Sorption Characteristics of Corn Stover and Big Bluestem

    Directory of Open Access Journals (Sweden)

    C. Karunanithy

    2013-01-01

    Full Text Available Moisture content is an important feedstock quality in converting it into energy through biochemical or thermochemical platforms. Knowledge of moisture sorption relationship is useful in drying and storage to preserve the quality of feedstocks. Moisture sorption isotherms for potential feedstocks such as corn stover and big bluestem are missing. EMC values of corn stover and big bluestem were determined using static gravimetric technique with saturated salt solutions (ERH 0.12–0.89 at different temperatures (20, 30, and 40°C. Depending upon the ERH values, EMC values were ranged from 8.0 to 19.6 and 8.8 to 19.2% db for corn stover and big bluestem, respectively, and they followed typical type II isotherm found in food materials. Nonlinear regression was used to fit five commonly used three-parameter isotherm models (i.e., modified Oswin model, modified Halsey model, modified Chung-Pfost model, modified Henderson model, and the modified Guggenheim-Anderson-de Boer (GAB model to the experimental data. Modified Halsey emerged as the best model with high F-statistic and R2 values with low Em and Es and fairly random scattered residual plot for corn stover and big bluestem. These models can be used to predict the equilibrium moisture content of these feedstocks starting from harvesting, drying, preprocessing, transportation, storage, and conversion.

  17. Investigating Resulting Residual Stresses during Mechanical Forming Process

    Science.gov (United States)

    Akinlabi, Stephen A.; Fatoba, Olawale S.; Mashinini, Peter M.; Akinlabi, Esther T.

    2018-03-01

    Most manufacturing processes such as machining, welding, heat treatment, laser forming, laser cladding and, laser metal deposition, etc. are subjected to a form of heat or energy to change the geometrical shape thus changing the inherent engineering and structural properties of the material. These changes often cause the development of locked up stresses referred to as residual stresses as a result of these activities. This study reports on the residual stresses developed due to the mechanical forming process to maintain a suitable structural integrity for the formed components. The result of the analysis through the X-ray diffraction confirmed that residual stresses were induced in the manufactured parts and further revealed that residual stresses were compressive in nature as found in the parent material but with values less than the parent material.

  18. Stover removal effects on continuous corn yield and nitrogen use efficiency under irrigation

    Science.gov (United States)

    Corn (Zea mays L.) residue or stover is harvested as supplemental feed for livestock and is a primary feedstock for cellulosic biofuels. Limited information is available on corn residue removal effects on grain yield under different nitrogen (N) fertilizer rates, irrigation rates and amelioration pr...

  19. Sampling and sample processing in pesticide residue analysis.

    Science.gov (United States)

    Lehotay, Steven J; Cook, Jo Marie

    2015-05-13

    Proper sampling and sample processing in pesticide residue analysis of food and soil have always been essential to obtain accurate results, but the subject is becoming a greater concern as approximately 100 mg test portions are being analyzed with automated high-throughput analytical methods by agrochemical industry and contract laboratories. As global food trade and the importance of monitoring increase, the food industry and regulatory laboratories are also considering miniaturized high-throughput methods. In conjunction with a summary of the symposium "Residues in Food and Feed - Going from Macro to Micro: The Future of Sample Processing in Residue Analytical Methods" held at the 13th IUPAC International Congress of Pesticide Chemistry, this is an opportune time to review sampling theory and sample processing for pesticide residue analysis. If collected samples and test portions do not adequately represent the actual lot from which they came and provide meaningful results, then all costs, time, and efforts involved in implementing programs using sophisticated analytical instruments and techniques are wasted and can actually yield misleading results. This paper is designed to briefly review the often-neglected but crucial topic of sample collection and processing and put the issue into perspective for the future of pesticide residue analysis. It also emphasizes that analysts should demonstrate the validity of their sample processing approaches for the analytes/matrices of interest and encourages further studies on sampling and sample mass reduction to produce a test portion.

  20. Anaerobic digestion of straw and corn stover: The effect of biological process optimization and pre-treatment on total bio-methane yield and energy performance.

    Science.gov (United States)

    Croce, Serena; Wei, Qiao; D'Imporzano, Giuliana; Dong, Renjie; Adani, Fabrizio

    2016-12-01

    Anaerobic digestion (AD) is a useful method for producing renewable energy/biofuel. Today, biogas production uses a large amount of energy crops (EC), with the effect of increasing AD costs and creating conflict between food/feed vs. energy use. A partial solution to this might be the substitution of EC with agricultural wastes, e.g. straw. Straw and corn stover are widely available in the world and approximately 1600millionMgyear -1 of these substrates are available. Straw can be useful used for biogas production but its characteristics limit its performance so that sometimes the energetic balance can be negative. In this review, the limits for the conversion of this substrate into biogas were investigated and solutions/proposals for getting higher straw biogas production performance are reported. In addition, energetic balances for untreated and pre-treated substrates are reported, giving indicative evaluations of the sustainability of straw and corn stover use for biogas production. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Radionuclides in Bayer process residues: previous analysis for radiological protection

    International Nuclear Information System (INIS)

    Cuccia, Valeria; Rocha, Zildete; Oliveira, Arno H. de

    2011-01-01

    Natural occurring radionuclides are present in many natural resources. Human activities may enhance concentrations of radionuclides and/or enhance potential of exposure to naturally occurring radioactive material (NORM). The industrial residues containing radionuclides have been receiving a considerable global attention, because of the large amounts of NORM containing wastes and the potential long term risks of long-lived radionuclides. Included in this global concern, this work focuses on the characterization of radioactivity in the main residues of Bayer process for alumina production: red mud and sand samples. Usually, the residues of Bayer process are named red mud, in their totality. However, in the industry where the samples were collected, there is an additional residues separation: sand and red mud. The analytical techniques used were gamma spectrometry (HPGe detector) and neutron activation analysis. The concentrations of radionuclides are higher in the red mud than in the sand. These solid residues present activities concentrations enhanced, when compared to bauxite. Further uses for the residues as building material must be more evaluated from the radiological point of view, due to its potential of radiological exposure enhancement, specially caused by radon emission. (author)

  2. Radionuclides in Bayer process residues: previous analysis for radiological protection

    Energy Technology Data Exchange (ETDEWEB)

    Cuccia, Valeria; Rocha, Zildete, E-mail: vc@cdtn.b, E-mail: rochaz@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Oliveira, Arno H. de, E-mail: heeren@nuclear.ufmg.b [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear

    2011-07-01

    Natural occurring radionuclides are present in many natural resources. Human activities may enhance concentrations of radionuclides and/or enhance potential of exposure to naturally occurring radioactive material (NORM). The industrial residues containing radionuclides have been receiving a considerable global attention, because of the large amounts of NORM containing wastes and the potential long term risks of long-lived radionuclides. Included in this global concern, this work focuses on the characterization of radioactivity in the main residues of Bayer process for alumina production: red mud and sand samples. Usually, the residues of Bayer process are named red mud, in their totality. However, in the industry where the samples were collected, there is an additional residues separation: sand and red mud. The analytical techniques used were gamma spectrometry (HPGe detector) and neutron activation analysis. The concentrations of radionuclides are higher in the red mud than in the sand. These solid residues present activities concentrations enhanced, when compared to bauxite. Further uses for the residues as building material must be more evaluated from the radiological point of view, due to its potential of radiological exposure enhancement, specially caused by radon emission. (author)

  3. Carbonation of residual brines produced by ammonia-soda process

    Science.gov (United States)

    Filippova, I. V.; Piriou, P.; Filippov, L. O.; Yvon, J.; Grandjean, M.

    2013-03-01

    This work deals with the carbonation of residual brines produced during the manufacture of soda ash to avoid the unsuitable phase transformation during the land storage. The study resulted in a demonstration pilot, which showed the feasibility of such an approach and the possibility of his extension to an industrial scale. Carbonation of the residual brines is a promising process as it entirely transforms Ca(OH)2, "CaOHCl" and CSH into calcite, avoids the further phase evolution, allows to obtain a neutral pH which considerably reduce the land storage impact on environment and shorten by around 10 % the global CO2 emission of the ammonia-soda process.

  4. Aqueous recovery of plutonium from pyrochemical processing residues

    International Nuclear Information System (INIS)

    Gray, L.W.; Gray, J.H.

    1984-01-01

    Pyrochemical processes provide rapid methods to reclaim plutonium from scrap residues. Frequently, however, these processes yield an impure plutonium product and waste residues that are contaminated with actinides and are therefore nondiscardable. The Savannah River Laboratory and Plant and the Rocky Flats Plant are jointly developing new processes using both pyrochemistry and aqueous chemistry to generate pure product and discardable waste. An example of residue being treated is that from the molten salt extraction (MSE), a mixture of NaCl, KCl, MgCl 2 , PuCl 3 , AmCl 3 , PuO 2 , and Pu 0 . This mixture is scrubbed with molten aluminum containing a small amount of magnesium to produce a nonhomogeneous Al-Pu-Am-Mg alloy. This process, which rejects most of the NaCl-KCl-MgCl 2 salts, results in a product easily dissolved in 6M HNO 3 -0.1M HF. Any residual chloride in the product is removed by precipitation with Hg(I) followed by centrifuging. Plutonium and americium are then separated by the standard Purex process. The americium, initially diverted to the solvent extraction waste stream, can either be recovered or sent to waste

  5. Food processing as a means for pesticide residue dissipation

    Directory of Open Access Journals (Sweden)

    Đorđević Tijana

    2016-01-01

    Full Text Available Pesticides are one of the major inputs used for increasing agricultural productivity of crops. However, their inadequate application may produce large quantities of residues in the environment and, once the environment is contaminated with pesticides, they may easily enter into the human food chain through plants, creating a potentially serious health hazard. Nowadays, consumers are becoming more aware of the importance of safe and high quality food products. Thus it is pertinent to explore simple, cost-effective strategies for decontaminating food from pesticides. Various food processing techniques, at industrial and/or domestical level, have been found to significantly reduce the contents of pesticide residues in most food materials. The extent of reduction varies with the nature of pesticides, type of commodity and processing steps. Pesticides, especially those with limited movement and penetration ability, can be removed with reasonable efficiency by washing, and the effectiveness of washing depends on pesticide solubility in water or in different chemical solvents. Peeling of fruit and vegetable skin can dislodge pesticide residues to varying degrees, depending on constitution of a commodity, chemical nature of the pesticide and environmental conditions. Different heat treatments (drying, pasteurization, sterilization, blanching, steaming, boiling, cooking, frying or roasting during various food preparation and preservation processes can cause losses of pesticide residues through evaporation, co-distillation and/or thermal degradation. Product manufactures, from the simplest grain milling, through oil extraction and processing, juicing/pureeing or canning of fruits and vegetables, to complex bakery and dairy production, malting and brewing, wine making and various fermentation processes, play a role in the reduction of pesticide contents, whereby each operation involved during processing usually adds to a cumulative effect of reduction of

  6. Multiscale deconstruction of molecular architecture in corn stover

    Science.gov (United States)

    Inouye, Hideyo; Zhang, Yan; Yang, Lin; Venugopalan, Nagarajan; Fischetti, Robert F.; Gleber, S. Charlotte; Vogt, Stefan; Fowle, W.; Makowski, Bryan; Tucker, Melvin; Ciesielski, Peter; Donohoe, Bryon; Matthews, James; Himmel, Michael E.; Makowski, Lee

    2014-01-01

    Lignocellulosic composite in corn stover is a candidate biofuel feedstock of substantial abundance and sustainability. Its utilization is hampered by resistance of constituent cellulose fibrils to deconstruction. Here we use multi-scale studies of pretreated corn stover to elucidate the molecular mechanism of deconstruction and investigate the basis of recalcitrance. Dilute acid pretreatment has modest impact on fibrillar bundles at 0.1 micron length scales while leading to significant disorientation of individual fibrils. It disintegrates many fibrils into monomeric cellulose chains or small side-by-side aggregates. Residual crystalline fibrils lose amorphous surface material, change twist and where still cross-linked, coil around one another. Yields from enzymatic digestion are largely due to hydrolysis of individual cellulose chains and fragments generated during pretreatments. Fibrils that remain intact after pretreatment display substantial resistance to enzymatic digestion. Optimization of yield will require strategies that maximize generation of fragments and minimize preservation of intact cellulosic fibrils.

  7. Predicting the residual aluminum level in water treatment process

    OpenAIRE

    J. Tomperi; M. Pelo; K. Leiviskä

    2013-01-01

    In water treatment processes, aluminum salts are widely used as coagulation chemical. High dose of aluminum has been proved to be at least a minor health risk and some evidence points out that aluminum could increase the risk of Alzheimer's disease. Thus it is important to minimize the amount of residual aluminum in drinking water and water used at food industry. In this study, the data of a water treatment plant (WTP) was analyzed and the residual aluminum in drinking water was predicted usi...

  8. Predicting the residual aluminum level in water treatment process

    OpenAIRE

    J. Tomperi; M. Pelo; K. Leiviskä

    2012-01-01

    In water treatment processes, aluminum salts are widely used as coagulation chemical. High dose of aluminum has been proved to be at least a minor health risk and some evidence points out that aluminum could increase the risk of Alzheimer's disease thus it is important to minimize the amount of residual aluminum in drinking water and water used at food industry. In this study, the data of a water treatment plant (WTP) was analyzed and the residual aluminum in drinking water was predicted usin...

  9. Shock treatment of corn stover.

    Science.gov (United States)

    Bond, Austin; Rughoonundun, Hema; Petersen, Eric; Holtzapple, Carol; Holtzapple, Mark

    2017-05-01

    Corn stover digestibility was enhanced via shock treatment. A slurry of lime-treated corn stover was placed in a partially filled closed vessel. From the ullage space, either a shotgun shell was fired into the slurry, or a gas mixture was detonated. Various conditions were tested (i.e., pressures, depth, solids concentrations, gas mixtures). A high pressurization rate (108,000 MPa/s shotgun shells; 4,160,000 MPa/s hydrogen/oxygen detonation) was the only parameter that improved enzymatic digestibility. Stoichiometric propane/air deflagration had a low pressurization rate (37.2 MPa/s) and did not enhance enzymatic digestibility. Without shock, enzymatic conversion of lime-treated corn stover was 0.80 g glucan digested/g glucan fed with an enzyme loading of 46.7 mg protein/g glucan. With shock, the enzyme loading was reduced by ∼2× while maintaining the same conversion. Detonations are extraordinarily fast; rapidly cycling three small vessels (0.575 m 3 each) every 7.5 s enables commercially relevant shock treatment (2,000 tone/day). © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:815-823, 2017. © 2017 American Institute of Chemical Engineers.

  10. Catalytic production of biofuels (butene oligomers) and biochemicals (tetrahydrofurfuryl alcohol) from corn stover.

    Science.gov (United States)

    Byun, Jaewon; Han, Jeehoon

    2016-07-01

    A strategy is presented that produces liquid hydrocarbon fuels (butene oligomers (BO)) from cellulose (C6) fraction and commodity chemicals (tetrahydrofurfuryl alcohol (THFA)) from hemicellulose (C5) of corn stover based on catalytic conversion technologies using 2-sec-butylphenol (SBP) solvents. This strategy integrates the conversion subsystems based on experimental studies and separation subsystems for recovery of biomass derivatives and SBP solvents. Moreover, a heat exchanger network is designed to reduce total heating requirements to the lowest level, which is satisfied from combustion of biomass residues (lignin and humins). Based on the strategy, this work offers two possible process designs (design A: generating electricity internally vs. design B: purchasing electricity externally), and performs an economic feasibility study for both the designs based on a comparison of the minimum selling price (MSP) of THFA. This strategy with the design B leads to a better MSP of $1.93 per kg THFA. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Effect of structural features on enzyme digestibility of corn stover.

    Science.gov (United States)

    Kim, Sehoon; Holtzapple, Mark T

    2006-03-01

    Corn stover was pretreated with excess calcium hydroxide (0.5 g Ca(OH)2/g raw biomass) in non-oxidative and oxidative conditions at 25, 35, 45, and 55 degrees C. The enzymatic digestibility of lime-treated corn stover was affected by the change of structural features (acetylation, lignification, and crystallization) resulting from the treatment. Extensive delignification required oxidative treatment and additional consumption of lime (up to 0.17 g Ca(OH)2/g biomass). Deacetylation reached a plateau within 1 week and there were no significant differences between non-oxidative and oxidative conditions at 55 degrees C; both conditions removed approximately 90% of the acetyl groups in 1 week at all temperatures studied. Delignification highly depended on temperature and the presence of oxygen. Lignin and hemicellulose were selectively removed (or solubilized), but cellulose was not affected by lime pretreatment in mild temperatures (25-55 degrees C), even though corn stover was contacted with alkali for a long time, 16 weeks. The degree of crystallinity slightly increased from 43% to 60% with delignification because amorphous components (lignin, hemicellulose) were removed. However, the increased crystallinity did not negatively affect the 3-d sugar yield of enzymatic hydrolysis. Oxidative lime pretreatment lowered the acetyl and lignin contents to obtain high digestibility, regardless of crystallinity. The non-linear models for 3-d hydrolysis yields of glucan (Y(g)), xylan (Y(x)), and holocellulose (Y(gx)) were empirically established as a function of the residual lignin (L) for the corn stover pretreated with lime and air.

  12. Conversion of sorghum stover into animal feed with white-rot fungi ...

    African Journals Online (AJOL)

    Treatment of crop residues with some species of white-rot fungi can enhance the nutritive value. After the fungal treatment of sorghum (Sorghum bicolor) stover with two white-rot fungi in a solid state fermentation, the chemical composition and in vitro digestibility of the resultant substrate was determined. The results show a ...

  13. Reductive Catalytic Fractionation of Corn Stover Lignin

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Eric M.; Katahira, Rui; Reed, Michelle; Resch, Michael G.; Karp, Eric M.; Beckham, Gregg T.; Román-Leshkov, Yuriy

    2016-12-05

    Reductive catalytic fractionation (RCF) has emerged as an effective biomass pretreatment strategy to depolymerize lignin into tractable fragments in high yields. We investigate the RCF of corn stover, a highly abundant herbaceous feedstock, using carbon-supported Ru and Ni catalysts at 200 and 250 degrees C in methanol and, in the presence or absence of an acid cocatalyst (H3PO4 or an acidified carbon support). Three key performance variables were studied: (1) the effectiveness of lignin extraction as measured by the yield of lignin oil, (2) the yield of monomers in the lignin oil, and (3) the carbohydrate retention in the residual solids after RCF. The monomers included methyl coumarate/ferulate, propyl guaiacol/syringol, and ethyl guaiacol/syringol. The Ru and Ni catalysts performed similarly in terms of product distribution and monomer yields. The monomer yields increased monotonically as a function of time for both temperatures. At 6 h, monomer yields of 27.2 and 28.3% were obtained at 250 and 200 degrees C, respectively, with Ni/C. The addition of an acid cocatalysts to the Ni/C system increased monomer yields to 32% for acidified carbon and 38% for phosphoric acid at 200 degrees C. The monomer product distribution was dominated by methyl coumarate regardless of the use of the acid cocatalysts. The use of phosphoric acid at 200 degrees C or the high temperature condition without acid resulted in complete lignin extraction and partial sugar solubilization (up to 50%) thereby generating lignin oil yields that exceeded the theoretical limit. In contrast, using either Ni/C or Ni on acidified carbon at 200 degrees C resulted in moderate lignin oil yields of ca. 55%, with sugar retention values >90%. Notably, these sugars were amenable to enzymatic digestion, reaching conversions >90% at 96 h. Characterization studies on the lignin oils using two-dimensional heteronuclear single quantum coherence nuclear magnetic resonance and gel permeation chromatrography revealed

  14. The LOMOsup(R) process: a solution for residual monomers

    International Nuclear Information System (INIS)

    Derbyshire, R.L.

    1979-01-01

    Regulatory activity over the last several years has addressed the potential problems associated with the migration of residual monomers from a number of commodity food packages. Regardless of the outcome of current debates, it will always be desirable to reduce monomer levels to as low a level as economically practicable so that they do not become indirect additives. The LOMO process is a body of technology inclusive of an ionizing radiation treatment which can result in sharp reduction of residual monomer levels in commodity plastic resins. The process may be applicable to factory intermediates, raw resins, or finished articles. Depending upon the individual system and its monomers, LOMO treatment can result in reductions to levels which press today's analytical test capability. Industrial radiation processing is normally accomplished with electron beam accelerators. Electron beam processing continues to gain in understanding and acceptance as one of the very few basic methods by which energy can be imparted to an industrial process system. Typically, whole factories are constructed around one accelerator. (author)

  15. Yields from pyrolysis of refinery residue using a batch process

    Directory of Open Access Journals (Sweden)

    S. Prithiraj

    2017-12-01

    Full Text Available Batch pyrolysis was a valuable process of assessing the potential of recovering and characterising products from hazardous waste materials. This research explored the pyrolysis of hydrocarbon-rich refinery residue, from crude oil processes, in a 1200 L electrically-heated batch retort. Furthermore, the off-gases produced were easily processed in compliance with existing regulatory emission standards. The methodology offers a novel, cost-effective and environmentally compliant method of assessing recovery potential of valuable products. The pyrolysis experiments yielded significant oil (70% with high calorific value (40 MJ/kg, char (14% with carbon content over 80% and non-condensable gas (6% with significant calorific value (240 kJ/mol. The final gas stream was subjected to an oxidative clean-up process with continuous on-line monitoring demonstrating compliance with South African emission standards. The gas treatment was overall economically optimal as only a smaller portion of the original residue was subjected to emission-controlling steps. Keywords: Batch pyrolysis, Volatiles, Oil yields, Char, Emissions, Oil recovery

  16. Green liquor pretreatment for improving enzymatic hydrolysis of corn stover.

    Science.gov (United States)

    Gu, Feng; Yang, Linfeng; Jin, Yongcan; Han, Qiang; Chang, Hou-min; Jameel, Hasan; Phillips, Richard

    2012-11-01

    Green liquor consists of sodium carbonate and sodium sulfide and is readily available in any kraft mills. The green liquor pretreatment process for bioethanol production was developed for wood chips. This process uses only proven technology and equipment currently used in a kraft pulp mill and has several additional advantages such as high sugar recovery and concentration, no inhibitive substances produced, as compared to acid-based pretreatment methods. The liquor was used to pretreat corn stover for enhancing enzymatic hydrolysis in bioethanol production. Pulp yield of 70% with 45% lignin removal was achieved under optimized conditions (8% total titratable alkali, 40% sulfidity and 140°C). About 70% of the original polysaccharides were converted into fermentable sugars, using 20 FPU/g-pulp of enzyme in the subsequent enzymatic hydrolysis. The result indicates that green liquor is a feasible pretreatment to improve the enzymatic saccharification of corn stover for bioethanol production. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Disposal of residue from uranium ore processing in France

    International Nuclear Information System (INIS)

    Crochon, Ph.

    2011-01-01

    Between 1949 and 2001, French mines produced 76, 000 metric tons of uranium and 50 million metric tons of ore, processing residues are stored at 17 sites (in ponds enclosed by dykes or in former open-cast mines) subject to ICPE (classified facility for environment protection) regulation. These disposal sites cover surface areas of between one and several tens of hectares and several thousands to several millions of metric tons of waste are stored at them. When uranium mining stopped in France, these sites were redeveloped, with caps placed over the residue to provide mechanical and radiological protection. All these sites are still monitored by AREVA. In the last fifteen years, these sites have been the subject of a number of studies, especially regarding the long-term evolution and impact of the residue. These studies are now being pursued within the framework of the national plan for the management of nuclear materials and waste (PNGMDR). A regulatory and institutional framework regarding long-term management of these disposal sites needs to be defined. (author)

  18. Nutrient and carbohydrate partitioning in sorghum stover

    International Nuclear Information System (INIS)

    Powell, J.M.; Hons, F.M.; McBee, G.G.

    1991-01-01

    Sorghum [Sorghum bicolor (L.) Moench] stover has been demonstrated to be a potential biomass energy source. Complete aboveground crop removal, however, can result in soil degradation. Differential dry matter, nutrient, and carbohydrate partitioning by sorghum cultivars may allow management strategies that return certain parts to the field while removing other portions for alternative uses, such as energy production. A field study was conducted to determine N,P,K, nonstructural carbohydrate, cellulose hemicellulose, and lignin distributions in stover of three diverse sorghum cultivars of differing harvest indices. Determinations were based on total vegetative biomass; total blades; total stalks; and upper middle, and lower blades and stalks. Concentrations of N and P were higher in blades than stalks and generally declines from upper to lower stover parts. Large carbohydrate and lignin concentration differences were observed on the basis of cultivar and stover part. Greater nutrient partitioning to the upper third of the intermediate and forage-type sorghum stovers was observed as compared to the conventional grain cultivar. Stover carbohydrates for all cultivars were mainly contained in the lower two-thirds of the stalk fraction. A system was proposed for returning upper stover portion to soil, while removing remaining portions for alternative uses

  19. Process Optimization for Valuable Metal Recovery from Dental Amalgam Residues

    Directory of Open Access Journals (Sweden)

    C.M. Parra–Mesa

    2009-07-01

    Full Text Available In this paper, the methodology used for optimizing leaching in a semi pilot plant is presented. This leaching process was applied to recover value metals from dental amalgam residues. 23 factorial design was used to characterize the process during the first stage and in the second one, a central compound rotational design was used for modeling copper percentage dissolved, a function of the nitric acid concentration, leaching time and temperature. This model explained the 81% of the response variability, which is considered satisfactory given the complexity of the process kinetics and, furthermore, it allowed the definition of the operation conditions for better copper recovery, which this was of 99.15%, at a temperature of 55°C, a concentration of 30% by weight and a time of 26 hours.

  20. Ethanol and biogas production after steam pretreatment of corn stover with or without the addition of sulphuric acid

    Directory of Open Access Journals (Sweden)

    Bondesson Pia-Maria

    2013-01-01

    Full Text Available Abstract Background Lignocellulosic biomass, such as corn stover, is a potential raw material for ethanol production. One step in the process of producing ethanol from lignocellulose is enzymatic hydrolysis, which produces fermentable sugars from carbohydrates present in the corn stover in the form of cellulose and hemicellulose. A pretreatment step is crucial to achieve efficient conversion of lignocellulosic biomass to soluble sugars, and later ethanol. This study has investigated steam pretreatment of corn stover, with and without sulphuric acid as catalyst, and examined the effect of residence time (5–10 min and temperature (190–210°C on glucose and xylose recovery. The pretreatment conditions with and without dilute acid that gave the highest glucose yield were then used in subsequent experiments. Materials pretreated at the optimal conditions were subjected to simultaneous saccharification and fermentation (SSF to produce ethanol, and remaining organic compounds were used to produce biogas by anaerobic digestion (AD. Results The highest glucose yield achieved was 86%, obtained after pretreatment at 210°C for 10 minutes in the absence of catalyst, followed by enzymatic hydrolysis. The highest yield using sulphuric acid, 78%, was achieved using pretreatment at 200°C for 10 minutes. These two pretreatment conditions were investigated using two different process configurations. The highest ethanol and methane yields were obtained from the material pretreated in the presence of sulphuric acid. The slurry in this case was split into a solid fraction and a liquid fraction, where the solid fraction was used to produce ethanol and the liquid fraction to produce biogas. The total energy recovery in this case was 86% of the enthalpy of combustion energy in corn stover. Conclusions The highest yield, comprising ethanol, methane and solids, was achieved using pretreatment in the presence of sulphuric acid followed by a process configuration in

  1. Delignification kinetics of corn stover in lime pretreatment.

    Science.gov (United States)

    Kim, Sehoon; Holtzapple, Mark T

    2006-03-01

    Corn stover was pretreated with excess calcium hydroxide (0.5 g Ca(OH)(2)/g raw biomass) in non-oxidative and oxidative conditions at 25, 35, 45, and 55 degrees C. The delignification kinetic model of corn stover used three first-order reactions with following forms: W(L) = 0.09 x exp(-infinity x t) + 0.28 x exp(-k(2) x t) + 0.63 x exp(-k(3) x t) in non-oxidative pretreatment; W(L) = 0.16 x exp(-infinity x t) + 0.27 x exp(-k(2) x t) + 0.57 x exp(-k(3) x t) in oxidative pretreatment. The first term corresponds to the initial phase, which is essentially infinite at the time scale of the reaction (weeks). The second and third terms correspond to the bulk and residual phases of delignification. The activation energies for delignification in the oxidative lime pretreatment reactions were estimated as 50.15 and 54.21 kJ/mol in the bulk and residual phases, respectively, which are similar to the Kraft delignification of bagasse, but much less than in Kraft delignification of wood.

  2. Microbial lipid production from corn stover via Mortierella isabellina.

    Science.gov (United States)

    Zhang, Jianguo; Hu, Bo

    2014-09-01

    Microbial lipid is a promising source of oil to produce biofuel if it can be generated from lignocellulosic materials. Mortierella isabellina is a filamentous fungal species featuring high content of oil in its cell biomass. In this work, M. isabellina was studied for lipid production from corn stover. The experimental results showed that M. isabellina could grow on different kinds of carbon sources including xylose and acetate, and the lipid content reached to 35 % at C/N ratio of 20. With dilution, M. isabellina could endure inhibition effects by dilute acid pretreatment of corn stover (0.3 g/L furfural, 1.2 g/L HMF, and 1 g/L 4-hydroxybenozic acid) and the strain formed pellets in the cell cultivations. An integrated process was developed combining the dilute acid pretreatment, cellulase hydrolysis, and cell cultivation for M. isabellina to convert corn stover to oil containing fungal biomass. With 7.5 % pretreated biomass solid loading ratio, the final lipid yield from sugar in pretreated biomass was 40 % and the final lipid concentration of the culture reached to 6.46 g/L.

  3. NUMERICAL SIMULATION OF RESIDUAL STRESSES GENERATED IN THE WIRE DRAWING PROCESS FOR DIFFERENT PROCESS PARAMETERS

    Directory of Open Access Journals (Sweden)

    Juliana Zottis

    2014-03-01

    Full Text Available The drawing process of steel bars is usually used to check better dimensional accuracy and mechanical properties to the material. In the other hand, the major concern found in manufacturing axes through this process is the appearance of distortion of shape. Such distortions are directly linked to the accumulation of residual stresses generated during the processes. As a result, this paper aims to study the influence of process parameters such as shape of puller, speed and lubrication used in wire drawing analyzing the accumulation of residual stress after the process. The stress analysis was performed by FEM being used two simulation software: Simufact.formingGP and DeformTM. Through these analyzes, it was found that the shape of how the bar is pulled causes a reduction of up to 100 MPa in residual stresses in the center of the bar, which represents an important factor in the study of the possible causes of the distortion. As well as factors speed and homogeneity of lubrication significantly altered the profile of residual stresses in the bar.

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

    Energy Technology Data Exchange (ETDEWEB)

    Allison E Ray; Amber Hoover; Gary Gresham

    2012-07-01

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

  5. Treatment of plutonium process residues by molten salt oxidation

    International Nuclear Information System (INIS)

    Stimmel, J.; Wishau, R.; Ramsey, K.B.; Montoya, A.; Brock, J.; Heslop, M.

    1999-01-01

    Molten Salt Oxidation (MSO) is a thermal process that can remove more than 99.999% of the organic matrix from combustible 238 Pu material. Plutonium processing residues are injected into a molten salt bed with an excess of air. The salt (sodium carbonate) functions as a catalyst for the conversion of the organic material to carbon dioxide and water. Reactive species such as fluorine, chlorine, bromine, iodine, sulfur, phosphorous and arsenic in the organic waste react with the molten salt to form the corresponding neutralized salts, NaF, NaCl, NaBr, NaI, Na 2 SO 4 , Na 3 PO 4 and NaAsO 2 or Na 3 AsO4. Plutonium and other metals react with the molten salt and air to form metal salts or oxides. Saturated salt will be recycled and aqueous chemical separation will be used to recover the 238 Pu. The Los Alamos National Laboratory system, which is currently in the conceptual design stage, will be scaled down from current systems for use inside a glovebox

  6. Treatment of plutonium process residues by molten salt oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Stimmel, J.; Wishau, R.; Ramsey, K.B.; Montoya, A.; Brock, J. [Los Alamos National Lab., NM (United States); Heslop, M. [Naval Surface Warfare Center (United States). Indian Head Div.; Wernly, K. [Molten Salt Oxidation Corp. (United States)

    1999-04-01

    Molten Salt Oxidation (MSO) is a thermal process that can remove more than 99.999% of the organic matrix from combustible {sup 238}Pu material. Plutonium processing residues are injected into a molten salt bed with an excess of air. The salt (sodium carbonate) functions as a catalyst for the conversion of the organic material to carbon dioxide and water. Reactive species such as fluorine, chlorine, bromine, iodine, sulfur, phosphorous and arsenic in the organic waste react with the molten salt to form the corresponding neutralized salts, NaF, NaCl, NaBr, NaI, Na{sub 2}SO{sub 4}, Na{sub 3}PO{sub 4} and NaAsO{sub 2} or Na{sub 3}AsO4. Plutonium and other metals react with the molten salt and air to form metal salts or oxides. Saturated salt will be recycled and aqueous chemical separation will be used to recover the {sup 238}Pu. The Los Alamos National Laboratory system, which is currently in the conceptual design stage, will be scaled down from current systems for use inside a glovebox.

  7. The Effect of Processing on 14C- Chlofenvinphos Residues in Maize Oil and Bioavailability of its Cake Residues on Rats

    International Nuclear Information System (INIS)

    Mahdy, F.; El-Maghraby, S.

    2008-01-01

    Maize seed obtained from 14 C-chlofenvinphos treated plants contained 0.12 % of the applied dose. The insecticide residues in crude oil, methanol and coke amounted to 10 %, 6 % and 69 %, respectively of original residues inside the seeds.The 14 C activity in the crude oil could be a gradual reduced by the refining processes. The alkali treatment and bleaching steps are more effective steps in the refining processes remove about (63 %). The refined oil contained only about 17 % of the 14 C-residues originally present. The major residues in processed oil contain parent compound, in addition to five metabolites of the insecticide. When rats fed the extracted seeds (cake), the bound residues were found to be considerably bioavailable. After feeding rats for 5 days with the cake, a substantial amount of 14 C-residues was eliminated in the urine (59.5 %), while about 20 % was excreted in the feces. About 15 % of the radioactivity was distribution among various organs

  8. Comparison of wet and dry corn stover harvest and storage

    Energy Technology Data Exchange (ETDEWEB)

    Shinners, Kevin J.; Binversie, Benjamin N. [University of Wisconsin, Madison, WI (United States). Department of Biological Systems Engineering; Muck, Richard E.; Weimer, Paul J. [US Dairy Forage Research Center, USDA-ARS, University of Wisconsin (United States)

    2007-04-15

    Corn stover has great potential as a biomass feedstock, but harvest and storage of this material is challenged by weather conditions at harvest; material moisture; and equipment shortcomings. Field drying characteristics, harvest efficiency and rate, product bulk density, and storage characteristics were quantified for stover harvested and stored in wet or dry form. Only in one case did stover reach dry baling moisture ({proportional_to}20%) in the first 4 d of field drying. Conventional hay and forage harvesting equipment (shredder, rake, forage harvester, round baler, and square baler) produced an average harvested yield of about 30% of the total available stover mass. Harvesting capacity of this equipment was limited by difficulty in gathering shredded stover. The density of chopped or baled stover was less than that typically expected with hay and forage crops. Losses of wet stover ensiled at 44% moisture averaged 3.9% with low levels of fermentation products. Dry stover losses were 3.3% and 18.1% for bales stored indoors and outdoors, respectively. Harvesting wet stover right after grain harvest was timelier and resulted in a greater harvesting rate and yield compared to dry stover harvest. Storing wet stover by ensiling resulted in lower losses and more uniform product moisture compared to dry stover bales stored outdoors. (author)

  9. Improved hydrogen production via thermophilic fermentation of corn stover by microwave-assisted acid pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chun-zhao; Cheng, Xi-yu [National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100093 (China)

    2010-09-15

    A microwave-assisted acid pretreatment (MAP) strategy has been developed to enhance hydrogen production via thermophilic fermentation of corn stover. Pretreatment of corn stover by combining microwave irradiation and acidification resulted in the increased release of soluble substances and made the corn stover more accessible to microorganisms when compared to thermal acid pretreatment (TAP). MAP showed obvious advantages in short duration and high efficiency of lignocellulosic hydrolysis. Analysis of the particle size and specific surface area of corn stover as well as observation of its cellular microstructure were used to elucidate the enhancement mechanism of the hydrolysis process by microwave assistance. The cumulative hydrogen volume reached 182.2 ml when corn stover was pretreated by MAP with 0.3 N H{sub 2}SO{sub 4} for 45 min, and the corresponding hydrogen yield reached 1.53 mol H{sub 2}/mol-glucose equivalents converted to organic end products. The present work demonstrates that MAP has potential to enhance the bioconversion efficiency of lignocellulosic waste to renewable biofuel. (author)

  10. Microclimate effects of crop residues on biological processes

    Science.gov (United States)

    Hatfield, J. L.; Prueger, J. H.

    1996-03-01

    Residues from crops left on the soil surface have an impact on the microclimate, primarily temperature, within the soil and the atmosphere; but, the impact on the biological system is largely unknown. Residue is assumed to have a positive impact on the biological system in the soil and a negative impact on crop growth. This report investigates the effect of standing residue on the microclimate surrounding a cotton ( Gossypium hirsutum L.) crop in a semi-arid environment and the effect of flat residue on the seasonal soil temperature and soil water regimes in a humid climate with a corn ( Zea mays L.) and soybean [ Glycine max (L.) Merr.] production system. A study was conducted during 1987 and 1988 in a semi-arid climate at Lubbock, Texas using standing wheat stubble to shelter cotton from wind. In this study soil water, microclimatic variables, and plant growth were measured within standing stubble and bare soil during the early vegetative growth period. Air temperatures were warmer at night within the standing residue and the air more humid throughout the day. This led to a reduction in the soil water evaporation rate and an increase in the water use efficiency of the cotton plant within the stubble. Studies on corn residue with continuous corn and corn-soybean rotations with no-till, chiselplow, and moldboard plow tillage practices in central Iowa showed that the average soil temperatures in the upper soil profile were not affected by the presence of flat residue after tillage. Diurnal temperature ranges were most affected by the residue throughout the year. The largest effect of the residue on soil temperature was in the fall after harvest when no-till fields cooled more slowly than tilled fields. In the spring, surface residue decreased the soil water evaporation rate and increased the soil water storage within the soil profile covered with residue. In years with below normal rainfall, the additional stored soil water due to the surface residue was used by the

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

    Directory of Open Access Journals (Sweden)

    Chen Ye

    2013-01-01

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

  12. Charred olive stones: experimental and archaeological evidence for recognizing olive processing residues used as fuel

    NARCIS (Netherlands)

    Braadbaart, Freek; Marinova, E.; Sarpaki, A.

    After extracting oil from olives a residue is left usually referred to as the olive oil processing residue (OPR). This study explores the way in which ancient societies may have used OPR as fuel for fires to generate heat and the various issues that are related to the residues of this fuel. After

  13. Bio-oil and bio-char production from corn cobs and stover by fast pyrolysis

    International Nuclear Information System (INIS)

    Mullen, Charles A.; Boateng, Akwasi A.; Goldberg, Neil M.; Lima, Isabel M.; Laird, David A.; Hicks, Kevin B.

    2010-01-01

    Bio-oil and bio-char were produced from corn cobs and corn stover (stalks, leaves and husks) by fast pyrolysis using a pilot scale fluidized bed reactor. Yields of 60% (mass/mass) bio-oil (high heating values are ∼20 MJ kg -1 , and densities >1.0 Mg m -3 ) were realized from both corn cobs and from corn stover. The high energy density of bio-oil, ∼20-32 times on a per unit volume basis over the raw corn residues, offers potentially significant savings in transportation costs particularly for a distributed 'farm scale' bio-refinery system. Bio-char yield was 18.9% and 17.0% (mass/mass) from corn cobs and corn stover, respectively. Deploying the bio-char co-product, which contains most of the nutrient minerals from the corn residues, as well as a significant amount of carbon, to the land can enhance soil quality, sequester carbon, and alleviate environmental problems associated with removal of crop residues from fields.

  14. Bio-oil and bio-char production from corn cobs and stover by fast pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Mullen, Charles A.; Boateng, Akwasi A.; Goldberg, Neil M.; Hicks, Kevin B. [Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 600 E. Mermaid Lane, Wyndmoor, PA 19038 (United States); Lima, Isabel M. [Southern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 1100 Robert E. Lee Blvd., New Orleans, LA 70124 (United States); Laird, David A. [National Soil Tilth Laboratory, U.S. Agricultural Research Service, U.S. Department of Agriculture, 2110 University Blvd., Ames, IA 50011 (United States)

    2010-01-15

    Bio-oil and bio-char were produced from corn cobs and corn stover (stalks, leaves and husks) by fast pyrolysis using a pilot scale fluidized bed reactor. Yields of 60% (mass/mass) bio-oil (high heating values are {proportional_to}20 MJ kg{sup -1}, and densities >1.0 Mg m{sup -3}) were realized from both corn cobs and from corn stover. The high energy density of bio-oil, {proportional_to}20-32 times on a per unit volume basis over the raw corn residues, offers potentially significant savings in transportation costs particularly for a distributed ''farm scale'' bio-refinery system. Bio-char yield was 18.9% and 17.0% (mass/mass) from corn cobs and corn stover, respectively. Deploying the bio-char co-product, which contains most of the nutrient minerals from the corn residues, as well as a significant amount of carbon, to the land can enhance soil quality, sequester carbon, and alleviate environmental problems associated with removal of crop residues from fields. (author)

  15. Comparative Analysis of Processes for Recovery of Rare Earths from Bauxite Residue

    Science.gov (United States)

    Borra, Chenna Rao; Blanpain, Bart; Pontikes, Yiannis; Binnemans, Koen; Van Gerven, Tom

    2016-11-01

    Environmental concerns and lack of space suggest that the management of bauxite residue needs to be re-adressed. The utilization of the residue has thus become a topic high on the agenda for both academia and industry, yet, up to date, it is only rarely used. Nonetheless, recovery of rare earth elements (REEs) with or without other metals from bauxite residue, and utilization of the left-over residue in other applications like building materials may be a viable alternative to storage. Hence, different processes developed by the authors for recovery of REEs and other metals from bauxite residue were compared. In this study, preliminary energy and cost analyses were carried out to assess the feasibility of the processes. These analyses show that the combination of alkali roasting-smelting-quenching-leaching is a promising process for the treatment of bauxite residue and that it is justified to study this process at a pilot scale.

  16. Advanced immobilization processes for fuel hulls and dissolver residues

    International Nuclear Information System (INIS)

    Hebel, W.; Boehme, G.; Findlay, J.R.; Sombret, C.

    1984-08-01

    Various research and development projects for the conditioning of cladding scraps and dissolver residues are pursued within the scope of the R and D programme on nuclear waste Management of the European Community. They include the characterization of the waste materials arising from industrial fuel reprocessing and the development of different waste immobilization techniques. These concern the embedment of scraps and residues into inert matrices like cement, metal alloys, compacted graphite and sintered ceramics as well as the treatment of the fuel hulls by melting or chemical conversion. The conditioned waste forms are tested as to their relevant properties for activity enclosure

  17. Life cycle implication of the potential commercialization of stover-based E85 in China

    International Nuclear Information System (INIS)

    Beibei Liu; Feng Wang; Wu Yunze; Bi Jun; Bu Maoliang; Juan Gao

    2012-01-01

    This article discusses an integrated framework built to compute the cost of stover-based E85, as well as its life cycle energy efficiency and CO 2 emission, with consideration of uncertainties of the policy-related factors, in China. Results show that co-product treatment greatly influenced the performance of E85 route. The calculated values of energy efficiency in co-product burning for electricity scenario (the base scenario) and that in co-product for selling scenario (the alternative scenario) are 4.41 and 3.61, respectively. CO 2 emission of the stover-based route is 99.7% more than that of the gasoline route in the base scenario and 55.3% less than that of the gasoline in the alternative scenario. The costs of E85 in these two scenarios are 9.78 and 7.76 yuan/L, respectively. Based on the sensitivity and uncertainty analysis, the article suggests the following: (1) stover-based E85 is currently not competitive in terms of cost; (2) on the current stage, to make E85 competitive, policymakers should be concerned about stimulating processing innovation, providing subsidies on ethanol, feedstock and co-product, as well as raising gasoline price, rather than increasing carbon tax rate/promoting Cleaner Development Mechanism (CDM) projects or influencing consumers’ Willingness to Pay (WTP) for E85. - Highlights: ► A framework to compute stover-based E85 cost, energy efficiency and CO 2 emission. ► Performance of stover-based E85 route depends largely on co-product treatment methods. ► Uncertainty of policy related factors is considered when simulating cost of E85. ► Stover-based E85 currently could hardly be competitive with gasoline in cost in China. ► Changes in consumers’ WTP and carbon tax rate have minor influences on the E85 cost.

  18. Tetracycline residue in fresh and processed Clarias gariepinus from ...

    African Journals Online (AJOL)

    This study was conducted to determine the tetracycline residue in Clarias gariepinus from selected fish farms and markets in Ibadan. Pre-tested structured questionnaire was administered to 116 consenting farmers to obtain information on antibiotic usage amongst others in five LGAs of Oyo State. Ten fish farms and two ...

  19. Modeling irregularly spaced residual series as a continuous stochastic process

    NARCIS (Netherlands)

    Von Asmuth, J.R.; Bierkens, M.F.P.

    2005-01-01

    In this paper, the background and functioning of a simple but effective continuous time approach for modeling irregularly spaced residual series is presented. The basic equations were published earlier by von Asmuth et al. (2002), who used them as part of a continuous time transfer function noise

  20. The Effects of Particle Size, Different Corn Stover Components, and Gas Residence Time on Torrefaction of Corn Stover

    Directory of Open Access Journals (Sweden)

    Sarah Rahn

    2012-04-01

    Full Text Available Large scale biofuel production will be possible only if significant quantities of biomass feedstock can be stored, transported, and processed in an economic and sustainable manner. Torrefaction has the potential to significantly reduce the cost of transportation, storage, and downstream processing through the improvement of physical and chemical characteristics of biomass. The main objective of this study was to investigate the effects of particle size, plant components, and gas residence time on the production of torrefied corn (Zea mays stover. Different particle sizes included 0.85 mm and 20 mm. Different stover components included ground corn stover, whole corn stalk, stalk shell and pith, and corn cob shell. Three different purge gas residence times were employed to assess the effects of interaction of volatiles and torrefied biomass. Elemental analyses were performed on all of the samples, and the data obtained was used to estimate the energy contents and energy yields of different torrefied biomass samples. Particle density, elemental composition, and fiber composition of raw biomass fractions were also determined. Stalk pith torrefied at 280 °C and stalk shell torrefied at 250 °C had highest and lowest dry matter loss, of about 44% and 13%, respectively. Stalk pith torrefied at 250 °C had lowest energy density of about 18–18.5 MJ/kg, while cob shell torrefied at 280 °C had the highest energy density of about 21.5 MJ/kg. The lowest energy yield, at 59%, was recorded for stalk pith torrefied at 280 °C, whereas cob and stalk shell torrefied at 250 °C had highest energy yield at 85%. These differences were a consequence of the differences in particle densities, hemicellulose quantities, and chemical properties of the original biomass samples. Gas residence time did not have a significant effect on the aforementioned parameters.

  1. Techno-economic analysis of using corn stover to supply heat and power to a corn ethanol plant - Part 2: Cost of heat and power generation systems

    International Nuclear Information System (INIS)

    Mani, S.; Sokhansanj, S.; Tagore, S.; Turhollow, A.F.

    2010-01-01

    This paper presents a techno-economic analysis of corn stover fired process heating (PH) and the combined heat and power (CHP) generation systems for a typical corn ethanol plant (ethanol production capacity of 170 dam 3 ). Discounted cash flow method was used to estimate both the capital and operating costs of each system and compared with the existing natural gas fired heating system. Environmental impact assessment of using corn stover, coal and natural gas in the heat and/or power generation systems was also evaluated. Coal fired process heating (PH) system had the lowest annual operating cost due to the low fuel cost, but had the highest environmental and human toxicity impacts. The proposed combined heat and power (CHP) generation system required about 137 Gg of corn stover to generate 9.5 MW of electricity and 52.3 MW of process heat with an overall CHP efficiency of 83.3%. Stover fired CHP system would generate an annual savings of 3.6 M$ with an payback period of 6 y. Economics of the coal fired CHP system was very attractive compared to the stover fired CHP system due to lower fuel cost. But the greenhouse gas emissions per Mg of fuel for the coal fired CHP system was 32 times higher than that of stover fired CHP system. Corn stover fired heat and power generation system for a corn ethanol plant can improve the net energy balance and add environmental benefits to the corn to ethanol biorefinery.

  2. Food processing as a means for pesticide residue dissipation

    OpenAIRE

    Đorđević Tijana; Đurović-Pejčev Rada

    2016-01-01

    Pesticides are one of the major inputs used for increasing agricultural productivity of crops. However, their inadequate application may produce large quantities of residues in the environment and, once the environment is contaminated with pesticides, they may easily enter into the human food chain through plants, creating a potentially serious health hazard. Nowadays, consumers are becoming more aware of the importance of safe and high quality food product...

  3. Pretreatment of corn stover for sugar production using dilute hydrochloric acid followed by lime.

    Science.gov (United States)

    Zu, Shuai; Li, Wen-zhi; Zhang, Mingjian; Li, Zihong; Wang, Ziyu; Jameel, Hasan; Chang, Hou-min

    2014-01-01

    In this study, a two stage process was evaluated to increase the sugar recovery. Firstly, corn stover was treated with diluted hydrochloric acid to maximize the xylose yield, and then the residue was treated with lime to alter the lignin structure and swell the cellulose surface. The optimal condition was 120 °C and 40 min for diluted hydrochloric acid pretreatment followed by lime pretreatment at 60 °C for 12h with lime loading at 0.1 g/g of substrate. The glucose and xylose yield was 78.0% and 97.0%, respectively, with cellulase dosage at 5 FPU/g of substrate. The total glucose yield increased to 85.9% when the cellulase loading was increased to 10 FPU/g of substrate. This two stage process was effective due to the swelling of the internal surface, an increase in the porosity and a decrease in the degree of polymerization. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Rheology of corn stover slurries during fermentation to ethanol

    Science.gov (United States)

    Ghosh, Sanchari; Epps, Brenden; Lynd, Lee

    2017-11-01

    In typical processes that convert cellulosic biomass into ethanol fuel, solubilization of the biomass is carried out by saccharolytic enzymes; however, these enzymes require an expensive pretreatment step to make the biomass accessible for solubilization (and subsequent fermentation). We have proposed a potentially-less-expensive approach using the bacterium Clostridium thermocellum, which can initiate fermentation without pretreatment. Moreover, we have proposed a ``cotreatment'' process, in which fermentation and mechanical milling occur alternately so as to achieve the highest ethanol yield for the least milling energy input. In order to inform the energetic requirements of cotreatment, we experimentally characterized the rheological properties of corn stover slurries at various stages of fermentation. Results show that a corn stover slurry is a yield stress fluid, with shear thinning behavior well described by a power law model. Viscosity decreases dramatically upon fermentation, controlling for variables such as solids concentration and particle size distribution. To the authors' knowledge, this is the first study to characterize the changes in the physical properties of biomass during fermentation by a thermophilic bacterium.

  5. Feasibility study for anaerobic digestion of agricultural crop residues. Dynatech report No. 1935

    Energy Technology Data Exchange (ETDEWEB)

    Ashare, E.; Buivid, M. G.; Wilson, E. H.

    1979-07-31

    The objective of this study was to provide cost estimates for the pretreatment/digestion of crop residues to fuel gas. A review of agricultural statistics indicated that the crop residues wheat straw, corn stover, and rice straw are available in sufficient quantity to provide meaningful supplies of gas. Engineering economic analyses were performed for digestion of wheat straw, corn stover, and rice straw for small farm-, cooperative-, and industrial scales. The small farm scale processed the residue from an average size US farm (400 acres), and the other sizes were two and three orders of magnitude greater. The results of the analyses indicate that the production of fuel gas from these residues is, at best, economically marginal, unless a credit can be obtained for digester effluent. The use of pretreatment can double the fuel gas output but will not be economically justifiable unless low chemical requirements or low cost chemicals can be utilized. Additional development is necessary in this area. Use of low cost hole-in-the-ground batch digestion results in improved economics for the small farm size digestion system, but not for the cooperative and industrial size systems. Recommendations arising from this study are continued development of autohydrolysis and chemical pretreatment of agricultural crop residues to improve fuel gas yields in an economically feasible manner; development of a low cost controlled landfill batch digestion process for small farm applications; and determination of crop residue digestion by-product values for fertilizer and refeed.

  6. Effects of storage and processing on residue levels of chlorpyrifos in soybeans.

    Science.gov (United States)

    Zhao, Liuwei; Ge, Jing; Liu, Fengmao; Jiang, Naiwen

    2014-05-01

    The residue levels of chlorpyrifos in soybeans during storage and processing were investigated. Soybeans were treated with chlorpyrifos aqueous solution and placed in a sealed plastic container. The residue of chlorpyrifos was determined in soybeans at six time points within 0 and 112days during storage and oil processing of the soybeans was conducted. The analysis of the residues of chlorpyrifos was carried out by gas chromatography-mass spectrometry (GC-MS). Results show that the dissipation of chlorpyrifos in soybeans is about 62% during the storage period. Moreover, the carryover of the residues from soybeans into oil is found to be related to the processing methods. Processing factor, which is defined as the ratio of chlorpyrifos residue concentration in oil sample to that in the soybean samples, was 11 and 0.25 after cold and hot pressing, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Chlorpyrifos residual behaviors in field crops and transfers during duck pellet feed processing.

    Science.gov (United States)

    Li, Rui; Wei, Wei; He, Liang; Hao, Lili; Ji, Xiaofeng; Zhou, Yu; Wang, Qiang

    2014-10-22

    Chlorpyrifos is a widely used organophosphorus pesticide in agricultural crops (including food) and animal feeds in China, resulting in heavy contamination. Many studies have focused on the food-processing effects on chlorpyrifos removal, but sufficient information is not observed for feed-processing steps. Here, chlorpyrifos residual behaviors in field crops and its transfers in duck pellet feed-processing steps were evaluated. In field trials, the highest residues for rice grain, shelled corn, and soybean seed were 12.0, 0.605, and 0.220 mg/kg, respectively. Residues of all rice grain and about half of shelled corn exceeded the maximum residue limits (MRLs) of China, and five soybean seeds exceeded the MRL of China. Chlorpyrifos residue was reduced 38.2% in brown rice after the raw rice grain was hulled. The residue in bran increased 71.2% after milling from brown rice. During the squashing step, the residue reduced 73.8% in soybean meal. The residues reduced significantly (23.7-36.8%) during the process of granulating for rice, maize, and soybean products. Comparatively, the grinding process showed only limited influence on chlorpyrifos removal (residues of duck pellet feeds produced from highly contaminated raw materials of this study were 1.01 mg/kg (maize-soybean feed) and 3.20 mg/kg (rice-soybean feed), which were much higher than the generally accepted value (>0.1 mg/kg) for animal feeding. Chlorpyrifos residues were removed significantly by processing steps of pellet feeds, but the residue of raw materials was the determining factor for the safety of duck feeding.

  8. Effect of household and industrial processing on levels of pesticide residues and degradation products in melons

    OpenAIRE

    Bonnechère, Aurore; Hanot, Vincent; Bragard, Claude; Bedoret, Thomas; Van Loco, Joris

    2012-01-01

    Abstract Two varieties of melons (Cucumis melo) were treated by two fungicides (carbendazim and maneb) and four insecticides (acetamiprid, cyromazin, imazalil and thiamethoxam) to quantify the effect of household processing on the pesticide residues. To ensure sufficiently high levels of residues in flesh and peels, the most concentrated formulations were applied pursuant to Good Agricultural Practices (GAPs). The peeling step decreased the concentration of pesticide residues for ...

  9. Soil water evaporation and crop residues

    Science.gov (United States)

    Crop residues have value when left in the field and also when removed from the field and sold as a commodity. Reducing soil water evaporation (E) is one of the benefits of leaving crop residues in place. E was measured beneath a corn canopy at the soil suface with nearly full coverage by corn stover...

  10. Variation behavior of residual stress distribution by manufacturing processes in welded pipes of austenitic stainless steel

    International Nuclear Information System (INIS)

    Ihara, Ryohei; Hashimoto, Tadafumi; Mochizuki, Masahito

    2012-01-01

    Stress corrosion cracking (SCC) has been observed near heat affected zone (HAZ) of primary loop recirculation pipes made of low-carbon austenitic stainless steel type 316L in the nuclear power plants. For the non-sensitization material, residual stress is the important factor of SCC, and it is generated by machining and welding. In the actual plants, welding is conducted after machining as manufacturing processes of welded pipes. It could be considered that residual stress generated by machining is varied by welding as a posterior process. This paper presents residual stress variation due to manufacturing processes of pipes using X-ray diffraction method. Residual stress distribution due to welding after machining had a local maximum stress in HAZ. Moreover, this value was higher than residual stress generated by welding or machining. Vickers hardness also had a local maximum hardness in HAZ. In order to clarify hardness variation, crystal orientation analysis with EBSD method was performed. Recovery and recrystallization were occurred by welding heat near the weld metal. These lead hardness decrease. The local maximum region showed no microstructure evolution. In this region, machined layer was remained. Therefore, the local maximum hardness was generated at machined layer. The local maximum stress was caused by the superposition effect of residual stress distributions due to machining and welding. Moreover, these local maximum residual stress and hardness are exceeded critical value of SCC initiation. In order to clarify the effect of residual stress on SCC initiation, evaluation including manufacturing processes is important. (author)

  11. Residual stress evaluation and curvature behavior of aluminium 7050 peen forming processed

    International Nuclear Information System (INIS)

    Oliveira, R.R. de; Lima, N.B.; Braga, A.P.V.; Goncalves, M.

    2010-01-01

    Shot peening is a superficial cold work process used to increase the fatigue life evaluated by residual stress measurements. The peen forming process is a variant of the shot peening process, where a curvature in the plate is obtained by the compression of the grains near to the surface. In this paper, the influence of the parameters such as: pressure of shot, ball shot size and thickness of aluminum 7050 samples with respect to residual stress profile and resulting arc height was studied. The evaluation of the residual stress profile was obtained by sin 2 Ψ method. (author)

  12. Modeled Impacts of Cover Crops and Vegetative Barriers on Corn Stover Availability and Soil Quality

    Energy Technology Data Exchange (ETDEWEB)

    Ian J. Bonner; David J. Muth Jr.; Joshua B. Koch; Douglas L. Karlen

    2014-06-01

    Environmentally benign, economically viable, and socially acceptable agronomic strategies are needed to launch a sustainable lignocellulosic biofuel industry. Our objective was to demonstrate a landscape planning process that can ensure adequate supplies of corn (Zea mays L.) stover feedstock while protecting and improving soil quality. The Landscape Environmental Assessment Framework (LEAF) was used to develop land use strategies that were then scaled up for five U.S. Corn Belt states (Nebraska, Iowa, Illinois, Indiana, and Minnesota) to illustrate the impact that could be achieved. Our results show an annual sustainable stover supply of 194 million Mg without exceeding soil erosion T values or depleting soil organic carbon [i.e., soil conditioning index (SCI)?>?0] when no-till, winter cover crop, and vegetative barriers were incorporated into the landscape. A second, more rigorous conservation target was set to enhance soil quality while sustainably harvesting stover. By requiring erosion to be <1/2 T and the SCI-organic matter (OM) subfactor to be >?0, the annual sustainable quantity of harvestable stover dropped to148 million Mg. Examining removal rates by state and soil resource showed that soil capability class and slope generally determined the effectiveness of the three conservation practices and the resulting sustainable harvest rate. This emphasizes that sustainable biomass harvest must be based on subfield management decisions to ensure soil resources are conserved or enhanced, while providing sufficient biomass feedstock to support the economic growth of bioenergy enterprises.

  13. Conversion of Aqueous Ammonia-Treated Corn Stover to Lactic Acid by Simultaneous Saccharification and Cofermentation

    Science.gov (United States)

    Zhu, Yongming; Lee, Y. Y.; Elander, Richard T.

    Treatment of corn stover with aqueous ammonia removes most of the structural lignin, whereas retaining the majority of the carbohydrates in the solids. After treatment, both the cellulose and hemicellulose in corn stover become highly susceptible to enzymatic digestion. In this study, corn stover treated by aqueous ammonia was investigated as the substrate for lactic acid production by simultaneous saccharification and cofermentation (SSCF). A commercial cellulase (Spezyme-CP) and Lactobacillus pentosus American Type Culture Collection (ATCC) 8041 (Spanish Type Culture Collection [CECT]-4023) were used for hydrolysis and fermentation, respectively. In batch SSCF operation, the carbohydrates in the treated corn stover were converted to lactic acid with high yields, the maximum lactic acid yield reaching 92% of the stoichiometric maximum based on total fermentable carbohydrates (glucose, xylose, and arabinose). A small amount of acetic acid was also produced from pentoses through the phosphoketolase pathway. Among the major process variables for batch SSCF, enzyme loading and the amount of yeast extract were found to be the key factors affecting lactic acid production. Further tests on nutrients indicated that corn steep liquor could be substituted for yeast extract as a nitrogen source to achieve the same lactic acid yield. Fed-batch operation of the SSCF was beneficial in raising the concentration of lactic acid to a maximum value of 75.0 g/L.

  14. Cellulosic ethanol fermentation using Saccharomyces cerevisiae seeds cultured by pretreated corn stover material.

    Science.gov (United States)

    Qureshi, Abdul Sattar; Zhang, Jian; Bao, Jie

    2015-03-01

    Utilization of lignocellulose materials to replace the pure glucose for preparation of the fermenting yeast seeds could reduce the cost of ethanol fermentation, because a large quantity of glucose is saved in the large-scale seed fermentor series. In this study, Saccharomyces cerevisiae DQ1 was cultured using the freshly pretreated corn stover material as the carbon source, and then the culture broth was used as the inoculation seeds after a series of seed transfer and inoculated into the ethanol production fermentor. The results show that the yeast cell growth and ethanol fermentation performance have essentially no difference when the yeast seeds were cultured by glucose, the corn stover hydrolysate liquid, and the pretreated corn stover solids as carbon sources, respectively. Approximately 22% of the yeast cell culture cost was saved, and the process flow sheet in industrial scale plants was simplified by using the pretreated corn stover for seed culture. The results provided a practical method for materials and operational cost reduction for cellulosic ethanol production.

  15. Anaerobic digestion of microalgae residues resulting from the biodiesel production process

    International Nuclear Information System (INIS)

    Ehimen, E.A.; Sun, Z.F.; Carrington, C.G.; Birch, E.J.; Eaton-Rye, J.J.

    2011-01-01

    The recovery of methane from post transesterified microalgae residues has the potential to improve the renewability of the 'microalgae biomass to biodiesel' conversion process as well as reduce its cost and environmental impact. This paper deals with the anaerobic digestion of microalgae biomass residues (post transesterification) using semi-continuously fed reactors. The influence of substrate loading concentrations and hydraulic retention times on the specific methane yield of the anaerobically digested microalgae residues was investigated. The co-digestion of the microalgae residues with glycerol as well as the influence of temperature was also examined. It was found that the hydraulic retention period was the most significant variable affecting methane production from the residues, with periods (>5 days) corresponding to higher energy recovery. The methane yield was also improved by a reduction in the substrate loading rates, with an optimum substrate carbon to nitrogen ratio of 12.44 seen to be required for the digestion process.

  16. Optimal temperature profiles for minimum residual stress in the cure process of polymer composites

    CSIR Research Space (South Africa)

    Gopal, AK

    2000-01-01

    Full Text Available model which includes the effects of chemical and thermal strains and the viscoelastic material behaviour. The process model is implemented to conduct a parametric study to observe the trends and characteristics of the residual stress history varying...

  17. Bioethanol production from corn stover using aqueous ammonia pretreatment and two-phase simultaneous saccharification and fermentation (TPSSF).

    Science.gov (United States)

    Li, Xuan; Kim, Tae Hyun; Nghiem, Nhuan P

    2010-08-01

    An integrated bioconversion process was developed to convert corn stover derived pentose and hexose to ethanol effectively. In this study, corn stover was pretreated by soaking in aqueous ammonia (SAA), which retained glucan ( approximately 100%) and xylan (>80%) in the solids. The pretreated carbohydrates-rich corn stover was converted to ethanol via two-phase simultaneous saccharification and fermentation (TPSSF). This single-reactor process employed sequential simultaneous saccharification and fermentation (SSF), i.e. pentose conversion using recombinant Escherichia coli KO11 in the first phase, followed by hexose conversion with Saccharomyces cerevisiae D5A in the second phase. In the first phase, 88% of xylan digestibility was achieved through the synergistic action of xylanase and endo-glucanase with minimal glucan hydrolysis (10.5%). Overall, the TPSSF using 12-h SAA-treated corn stover resulted in the highest ethanol concentration (22.3g/L), which was equivalent to 84% of the theoretical ethanol yield based on the total carbohydrates (glucan+xylan) in the untreated corn stover. (c) 2010 Elsevier Ltd. All rights reserved.

  18. RESIDUAL TLC SILICA GEL: RECUPERATION PROCESS, CHARACTERIZATION AND APPLICATION.

    Directory of Open Access Journals (Sweden)

    Maria Alexsandra de Sousa Rios

    2017-06-01

    Full Text Available A utilização de sílica gel de forma intensiva em laboratórios químicos tem um custo elevado, e gera uma quantidade significativa de resíduos sólidos contaminados com compostos orgânicos. Nesse sentido, a busca de métodos eficazes para reduzir os impactos que este material pode causar ao meio ambiente, tem sido um fator de motivação para muitos pesquisadores, uma vez que a sua utilização tem crescido bastante no segmento de pesquisa científica. Assim, o presente trabalho apresenta o processo de recuperação, caracterização e aplicação do gel de sílica 60G, um adsorvente usado na preparação de Cromatografia de Camada Fina. De acordo com os resultados, o método proposto foi capaz de recuperar o gel de sílica residual, tornando-se possível, para ser reutilizado no processo de separação e/ou purificação de compostos orgânicos de um modo prático e com um impacto ambiental reduzido.

  19. Corn Belt soil carbon and macronutrient budgets with projected sustainable stover harvest

    Science.gov (United States)

    Tan, Zhengxi; Liu, Shu-Guang

    2015-01-01

    Corn (Zea mays L.) stover has been identified as a prime feedstock for biofuel production in the U.S. Corn Belt because of its perceived abundance and availability, but long-term stover harvest effects on regional nutrient budgets have not been evaluated. We defined the minimum stover requirement (MSR) to maintain current soil organic carbon levels and then estimated current and future soil carbon (C), nitrogen (N), phosphorus (P), and potassium (K) budgets for various stover harvest scenarios. Analyses for 2006 through 2010 across the entire Corn Belt indicated that currently, 28 Tg or 1.6 Mg ha−1 of stover could be sustainably harvested from 17.95 million hectares (Mha) with N, P, and K removal of 113, 26, and 47 kg ha−1, respectively, and C removal for that period was estimated to be 4.55 Mg C ha−1. Assuming continued yield increases and a planted area of 26.74 Mha in 2050, 77.4 Tg stover (or 2.4 Mg ha−1) could be sustainably harvested with N, P, and K removal of 177, 37, and 72 kg ha−1, respectively, along with C removal of ∼6.57 Mg C ha−1. Although there would be significant variation across the region, harvesting only the excess over the MSR under current fertilization rates would result in a small depletion of soil N (−5 ± 27 kg ha−1) and K (−20 ± 31 kg ha−1) and a moderate surplus of P (36 ± 18 kg ha−1). Our 2050 projections based on continuing to keep the MSR, but having higher yields indicate that soil N and K deficits would become larger, thus emphasize the importance of balancing soil nutrient supply with crop residue removal.

  20. Flexible biorefinery for producing fermentation sugars, lignin and pulp from corn stover.

    Science.gov (United States)

    Kadam, Kiran L; Chin, Chim Y; Brown, Lawrence W

    2008-05-01

    A new biorefining process is presented that embodies green processing and sustainable development. In the spirit of a true biorefinery, the objective is to convert agricultural residues and other biomass feedstocks into value-added products such as fuel ethanol, dissolving pulp, and lignin for resin production. The continuous biomass fractionation process yields a liquid stream rich in hemicellulosic sugars, a lignin-rich liquid stream, and a solid cellulose stream. This paper generally discusses potential applications of the three streams and specifically provides results on the evaluation of the cellulose stream from corn stover as a source of fermentation sugars and specialty pulp. Enzymatic hydrolysis of this relatively pure cellulose stream requires significantly lower enzyme loadings because of minimal enzyme deactivation from nonspecific binding to lignin. A correlation was shown to exist between lignin removal efficiency and enzymatic digestibility. The cellulose produced was also demonstrated to be a suitable replacement for hardwood pulp, especially in the top ply of a linerboard. Also, the relatively pure nature of the cellulose renders it suitable as raw material for making dissolving pulp. This pulping approach has significantly smaller environmental footprint compared to the industry-standard kraft process because no sulfur- or chlorine-containing compounds are used. Although this option needs some minimal post-processing, it produces a higher value commodity than ethanol and, unlike ethanol, does not need extensive processing such as hydrolysis or fermentation. Potential use of low-molecular weight lignin as a raw material for wood adhesive production is discussed as well as its use as cement and feed binder. As a baseline application the hemicellulosic sugars captured in the hydrolyzate liquor can be used to produce ethanol, but potential utilization of xylose for xylitol fermentation is also feasible. Markets and values of these applications are

  1. Thermal and catalytic ASVAHL processes under hydrogen pressure for converting heavy crudes and conventional residues

    Energy Technology Data Exchange (ETDEWEB)

    Peries, J.P.; Quignard, A.; Farjon, C.; Laborde, M.

    This article describes the comparative performances of thermal ASVAHL processes (TERVAHL T, TERVAHL H, TERVAHL HC) and catalytic ASVAHL processes (HYVAHL F, HYVAHL C) for two types of processing: (1) degasolined Boscan crude (basis of studies for transportation feasibility), and (2) Safaniya vacuum residue (basis of studies for residue refining). The results reveal the importance of the amount of fixed hydrogen, which affects the conversion obtained and the quality of the residues. The introduction of a TERVAHL HC soluble catalyst or one in catalytic suspension (catalytic hydrovisbreaking) or the use of a supported catalyst (HYVAHL hydrotreatment) enhances the activation of hydrogen. The combination of cracking, polycondensation and hydrogen reactions together with the operating conditions (temperatures, residence time and pressure) are what will define the conversion limits for a given stability of residues.

  2. Residual Stress Evaluation of Weld Inlay Process on Reactor Vessel Nozzles

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Kihyun; Cho, Hong Seok [KEPCO KPS, Naju (Korea, Republic of)

    2015-10-15

    Weld overlay, weld inlay and stress improvement are mitigation technologies for butt joints. Weld overlay is done on pressurizer nozzles which are the highest potential locations occurring PWSCC due to high temperature in Korea. Reactor vessel nozzles are other big safety concerns for butt joints. Weld overlay and stress improvement should be so difficult to apply to those locations because space is too limited. Weld inlay should be one of the solutions. KEPCO KPS has developed laser welding system and process for reactor nozzles. Welding residual stress analysis is necessary for flaw evaluation. United States nuclear regulatory commission has calculated GTAW(Gas Tungsten Arc Welding) residual stress using ABAQUS. To confirm effectiveness of weld inlay process, welding residual stress analysis was performed. and difference between GTAW and LASER welding process was compared. Evaluation of weld inlay process using ANSYS and ABAQUS is performed. All of the both results are similar. The residual stress generated after weld inlay was on range of 450-500 MPa. Welding residual stresses are differently generated by GTAW and LASER welding. But regardless of welding process type, residual tensile stress is generated on inside surface.

  3. Residual Stress Evaluation of Weld Inlay Process on Reactor Vessel Nozzles

    International Nuclear Information System (INIS)

    Cho, Kihyun; Cho, Hong Seok

    2015-01-01

    Weld overlay, weld inlay and stress improvement are mitigation technologies for butt joints. Weld overlay is done on pressurizer nozzles which are the highest potential locations occurring PWSCC due to high temperature in Korea. Reactor vessel nozzles are other big safety concerns for butt joints. Weld overlay and stress improvement should be so difficult to apply to those locations because space is too limited. Weld inlay should be one of the solutions. KEPCO KPS has developed laser welding system and process for reactor nozzles. Welding residual stress analysis is necessary for flaw evaluation. United States nuclear regulatory commission has calculated GTAW(Gas Tungsten Arc Welding) residual stress using ABAQUS. To confirm effectiveness of weld inlay process, welding residual stress analysis was performed. and difference between GTAW and LASER welding process was compared. Evaluation of weld inlay process using ANSYS and ABAQUS is performed. All of the both results are similar. The residual stress generated after weld inlay was on range of 450-500 MPa. Welding residual stresses are differently generated by GTAW and LASER welding. But regardless of welding process type, residual tensile stress is generated on inside surface

  4. Major leaching processes of combustion residues - Characterisation, modelling and experimental investigation

    Energy Technology Data Exchange (ETDEWEB)

    Yan Jinying

    1998-12-31

    Characterising leaching behaviour provides ample evidence to identify the major leaching processes of combustion residues. Neutralisation and chemical weathering govern the leaching reactions and control the release of elements from combustion residues, and are thus considered to be the major leaching processes. According to experimental investigations and geochemical simulations, the leaching kinetics of buffering materials are key issues for the understanding of the neutralizing processes. The acid neutralizing capacity at different pH levels depends mainly on the mineralogy of the combustion residues. In combustion residues, the dissolution of glass phases is expected to play an important role in a long-term neutralizing process. The neutralizing process in a flow system is significantly different from that in a batch system. The neutralizing ability of a combustion residue may be strongly affected by solute transport and carbonation reactions in a natural leaching environment. The chemical weathering mainly involves the matrix of combustion residues consisting mostly of glass phases. The dissolution kinetics of waste glass and other possible processes involved in the chemical weathering have been investigated and incorporated into a kinetic reactive transport model. Most important processes in the chemical weathering can be simulated simultaneously using this model. The results show that there is a complicated relationship between the factors controlling the long-term chemical weathering. The environmental impact of the glass dissolution cannot be neglected. Although the glass dissolution provides considerable buffering capacity in long-term weathering, the carbonate is usually a dominant buffering mineral in actual weathering processes. The transformation of carbonate should be considered as an important process in the chemical weathering. The formation of secondary minerals may considerably alter the mineralogy of the waste, and thus change the leaching

  5. Nondestructive control of residual stresses during welding and recharge processes

    International Nuclear Information System (INIS)

    Suarez, J.C.; Fernandez, L.M.; Cruz, C.; Merino, F.; Aragon, B.

    1993-01-01

    In this work, the stress state of material during welding and recharge processes is controlled with the help of Barkhausen effect. The changes, occurred in the longitudinal and transversal stress profile are show during deposition of welding rings. It is proved that the stress state of the base-material depends on the amount of recharge layers, deposited on it

  6. An Optimal Cure Process to Minimize Residual Void and Optical Birefringence for a LED Silicone Encapsulant

    Directory of Open Access Journals (Sweden)

    Min-Jae Song

    2014-05-01

    Full Text Available Silicone resin has recently attracted great attention as a high-power Light Emitting Diode (LED encapsulant material due to its good thermal stability and optical properties. In general, the abrupt curing reaction of the silicone resin for the LED encapsulant during the curing process induces reduction in the mechanical and optical properties of the LED product due to the generation of residual void and moisture, birefringence, and residual stress in the final formation. In order to prevent such an abrupt curing reaction, the reduction of residual void and birefringence of the silicone resin was observed through experimentation by introducing the multi-step cure processes, while the residual stress was calculated by conducting finite element analysis that coupled the heat of cure reaction and cure shrinkage. The results of experiment and analysis showed that it was during the three-step curing process that the residual void, birefringence, and residual stress reduced the most in similar tendency. Through such experimentation and finite element analysis, the study was able to confirm that the optimization of the LED encapsulant packaging process was possible.

  7. Feasibility study for anaerobic digestion of agricultural crop residues. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Ashare, E.; Buivid, M. G.; Wilson, E. H.

    1979-10-01

    This study provides cost estimates for the pretreatment/digestion of crop residues to fuel gas. Agricultural statistics indicate that the crop residues wheat straw, corn stover, and rice straw are available in sufficient quantity to provide meaningful supplies of gas. Engineering economic analyses were performed for digestion of sheat straw, corn stover, and rice straw for small farm, cooperative, and industrial scales. The results of the analyses indicate that the production of fuel gas from these residues is, at best, economically marginal, unless a credit can be obtained for digester effluent. The use of pretreatment can double the fuel gas output but will not be economically justifiable unless low chemical requirements or low-cost chemicals can be utilized. Use of low-cost hole-in-the-ground batch digestion results in improved economics for the small farm size digestion system, but not for the cooperative and industrial size systems. Recommendations arising from this study are continued development of autohydrolysis and chemical pretreatment of agricultural crop residues to improve fuel gas yields in an economically feasible manner; development of a low-cost controlled landfill batch digestion process for small farm applications; and determination of crop residue digestion by-product values for fertilizer and refeed.

  8. Determination of properties of clean coal technology post-process residue

    Directory of Open Access Journals (Sweden)

    Agnieszka Klupa

    2016-01-01

    Full Text Available This article presents the possibilities of using modern measuring devices to determine the properties of process residues (Polish acronym: UPP. UPP was taken from the combustion process from a power plant in Silesia. Determining the properties of UPP is the basis for making decisions about its practical application, for example, as a raw material to obtain useful products such as: pozzolan, cenosphere or zeolite, for which there is demand. The development of advanced technology and science has given rise to modern and precise research tools that contribute to the development of appropriate methods to assess the properties of post-process residue. For this study the following were used: scanning electron microscope with EDS microanalysis and an analyzer for particle size-, shape- and number- analysis. The study conducted confirms the effectiveness of SEM analysis to determine the properties of post-process residue from Clean Coal Technologies (CCT. The results obtained are an introduction to further research on the determination of properties of CCT post-process residue. Research to determine the properties of CCT post-process residue only began relatively recently.

  9. An Auto-Associative Residual Processing and K-means Clustering Approach for Anemometer Health Assessment

    Directory of Open Access Journals (Sweden)

    David Siegel

    2011-01-01

    Full Text Available This paper presents a health assessment methodology, as well as specific residual processing and figure of merit algorithms for anemometers in two different configurations. The methodology and algorithms are applied to data sets provided by the Prognostics and Health Management Society 2011 Data Challenge. The two configurations consist of the “paired” data set in which two anemometers are positioned at the same height, and the “shear” data set which includes an array of anemometers at different heights. Various wind speed statistics, wind direction, and ambient temperature information are provided, in which the objective is to classify the anemometer health status during a set of samples from a 5 day period. The proposed health assessment methodology consists of a set of data processing steps that include: data filtering and pre-processing, a residual or difference calculation, and a k-means clustering based figure of merit calculation. The residual processing for the paired data set was performed using a straightforward difference calculation, while the shear data set utilized an additional set of algorithm processing steps to calculate a weighted residual value for each anemometer. The residual processing algorithm for the shear data set used a set of auto-associative neural network models to learn the underlying correlation relationship between the anemometer sensors and to calculate a weighted residual value for each of the anemometer wind speed measurements. A figure of merit value based on the mean value of the smaller of the two clusters for the wind speed residual is used to determine the health status of each anemometer. Overall, the proposed methodology and algorithms show promise, in that the results from this approach resulted in the top score for the PHM 2011 Data Challenge Competition. Using different clustering algorithms or density estimation methods for the figure of merit calculation is being considered for future work.

  10. Efficiency of the refining processes in removing 14C-dichlorvos residues in soybean oil

    International Nuclear Information System (INIS)

    Soliman, S.M.

    2006-01-01

    Crude soybean oil extracted from grains treated with 14 C-dichlorvos at a dose 24 mg insecticide / kg seeds and stored for 30 weeks was subjected to different refining processes such as alkali treatment, bleaching, winterization and deodorization. The effect of the refining processes on the nature and magnitude of the originally present residues was investigated. The insecticide residues in crude oil and cake amounted to 9.5% and 55% , respectively, of original residues inside the seeds. Extraction of the seeds with hexane gave crude oil with 9.5 % of original residues in seeds. The l4 C-activity in the crude stored Soya beans oil could be reduced by about 82% of radioactivity originally present in crude oil eliminated by simulated commercial processes locally used for oil refining. A high percentage of the residues (50-55%) were eliminated during alkali treatment and bleaching. Refining of soybeans oil fortified with '1 4 C-dichlorovos. The final refined oil had only 13% of the radioactivity originally present, mainly in the form of dichlorvos, dimethyl and monomethyl phosphate in addition to desmethyl dichlorvos in oil with aged residues

  11. Residue and heavy-oil conversion by thermal cracking: the TERVAHL processes

    Energy Technology Data Exchange (ETDEWEB)

    Billon, A.; Bousquet, J.

    1987-01-01

    This paper presents a report on the TERVAHL process for residue and heavy-oil conversion by thermal cracking. The principles of thermal cracking and the main characteristics of the TERVAHL processes are first examined, then the advantages for producers of extra-heavy crude and for refiners are presented. The TERVAHL T and TERVAHL H processes belong to the family of visbreaking processes characterized by a moderate conversion level below the threshold of the appearance of very viscous and unstable pitch. They improve viscosity at the production site for the producer of heavy crude and for the refiner, the visbreaking of residues by residues by using hydrogen pressure, and the preparation of feedstocks for deasphalting or hydroconversion.

  12. Residual stress evaluation and curvature behavior of aluminium 7050 peen forming processed; Avaliacao da tensao residual em aluminio 7050 conformado pelo processo peen forming

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, R.R. de; Lima, N.B., E-mail: rolivier@ipen.b, E-mail: nblima@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Braga, A.P.V.; Goncalves, M., E-mail: anapaola@ipt.b, E-mail: mgoncalves@ipt.b [Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, SP (Brazil)

    2010-07-01

    Shot peening is a superficial cold work process used to increase the fatigue life evaluated by residual stress measurements. The peen forming process is a variant of the shot peening process, where a curvature in the plate is obtained by the compression of the grains near to the surface. In this paper, the influence of the parameters such as: pressure of shot, ball shot size and thickness of aluminum 7050 samples with respect to residual stress profile and resulting arc height was studied. The evaluation of the residual stress profile was obtained by sin{sup 2} {Psi} method. (author)

  13. Residues of ¹⁴C-ethion along the extraction and refining process of maize oil, and the bioavailability of bound residues in the cake for experimental animals.

    Science.gov (United States)

    Abdel-Gawad, H; Abdel-Hameed, R M; Witczak, A

    2013-08-01

    Maize seeds obtained from ¹⁴C-ethion treated plants contained about 0.01 % of the originally applied radioactivity 1 month following the last pesticide application. Hexane and methanol extracts of the seeds accounted for 35 % and 22.5 % of the radioactive residues, respectively, with 40 % remaining in the seed cake. Commercial processing procedures resulted in a gradual decrease in the total amount of ¹⁴C-residues in oils with aged residues. The refined oil contained ¹⁴C-residues that amounted to about 30 % of the amount that was originally present. The major residues in processed oil are ethion monooxon, O,O-diethyl phosphorothioate and O,O-diethyl S-hydroxymethyl phosphorodithioate, in addition to one unknown compound. After feeding rats with the cake containing ethion bound residues, a substantial amount (71 %) of ¹⁴C-residues was eliminated in the urine, while about 12 % was excreted in the feces. About 5 % of the radioactive residues were distributed among various organs. The bound residue was quite readily bioavailable to the rats.

  14. Earthworms modify microbial community structure and accelerate maize stover decomposition during vermicomposting.

    Science.gov (United States)

    Chen, Yuxiang; Zhang, Yufen; Zhang, Quanguo; Xu, Lixin; Li, Ran; Luo, Xiaopei; Zhang, Xin; Tong, Jin

    2015-11-01

    In the present study, maize stover was vermicomposted with the epigeic earthworm Eisenia fetida. The results showed that, during vermicomposting process, the earthworms promoted decomposition of maize stover. Analysis of microbial communities of the vermicompost by high-throughput pyrosequencing showed more complex bacterial community structure in the substrate treated by the earthworms than that in the control group. The dominant microbial genera in the treatment with the earthworms were Pseudoxanthomonas, Pseudomonas, Arthrobacter, Streptomyces, Cryptococcus, Guehomyces, and Mucor. Compared to the control group, the relative abundance of lignocellulose degradation microorganisms increased. The results indicated that the earthworms modified the structure of microbial communities during vermicomposting process, activated the growth of lignocellulose degradation microorganisms, and triggered the lignocellulose decomposition.

  15. Effect of commercial processing procedures on 14C-LINDANE residues in corn oil

    International Nuclear Information System (INIS)

    Soliman, S.M.

    2006-01-01

    At blooming, maize plants were sprayed twice, 23 days apart, at a dose of 22 mg equivalent to 5 μCi/ plant. At post harvest, maize seeds had a radioactivity corresponding to 0.36% of the applied dose. The insecticide residues in crude oil, cake and methanolic extract were amounted to 8 % and 60 % 5 % , respectively, of original residues inside the seeds.The 14 C-activity in the crude oil could be reduced by commercial processes locally used for refining. The refined oil had a residue level of about 0.7 ppm mainly in the form of unchanged lindane in addition to a number of chloro phenols as main metabolites. Refining of corn oil fortified with 14 C-lindane led to a high reduction of 14 C-lindane (88%). The refined oil contained a residue consisting lindane and its chloro phenols

  16. Corn stover harvest increases herbicide movement to subsurface drains: RZWQM simulations

    Science.gov (United States)

    Shipitalo, Martin J.; Malone, Robert W.; Ma, Liwang; Nolan, Bernard T.; Kanwar, Rameshwar S.; Shaner, Dale L.; Pederson, Carl H.

    2016-01-01

    BACKGROUND Crop residue removal for bioenergy production can alter soil hydrologic properties and the movement of agrochemicals to subsurface drains. The Root Zone Water Quality Model (RZWQM), previously calibrated using measured flow and atrazine concentrations in drainage from a 0.4 ha chisel-tilled plot, was used to investigate effects of 50 and 100% corn (Zea mays L.) stover harvest and the accompanying reductions in soil crust hydraulic conductivity and total macroporosity on transport of atrazine, metolachlor, and metolachlor oxanilic acid (OXA). RESULTS The model accurately simulated field-measured metolachlor transport in drainage. A 3-yr simulation indicated that 50% residue removal decreased subsurface drainage by 31% and increased atrazine and metolachlor transport in drainage 4 to 5-fold when surface crust conductivity and macroporosity were reduced by 25%. Based on its measured sorption coefficient, ~ 2-fold reductions in OXA losses were simulated with residue removal. CONCLUSION RZWQM indicated that if corn stover harvest reduces crust conductivity and soil macroporosity, losses of atrazine and metolachlor in subsurface drainage will increase due to reduced sorption related to more water moving through fewer macropores. Losses of the metolachlor degradation product OXA will decrease due to the more rapid movement of the parent compound into the soil.

  17. ALKALI EXTRACTION OF HEMICELLULOSE FROM DEPITHED CORN STOVER AND EFFECTS ON SODA-AQ PULPING

    OpenAIRE

    Heli Cheng; Huaiyu Zhan; Shiyu Fu; Lucian A. Lucia

    2011-01-01

    A biorefinery using the process of hemicellulose pre-extraction and subsequent pulping provides a promising way for the utilization of straw biomass and resolution of problems related to silicon. In this work, hemicellulose was extracted from depithed corn stover with sodium hydroxide solution before soda-AQ pulping. Components of the extracts were quantified by ion chromatography. The parameters (alkali concentration and temperature) affecting hemicellulose pre-extraction were optimized. The...

  18. Compatibility of High-Moisture Storage for Biochemical Conversion of Corn Stover: Storage Performance at Laboratory and Field Scales

    Directory of Open Access Journals (Sweden)

    Lynn M. Wendt

    2018-03-01

    Full Text Available Wet anaerobic storage of corn stover can provide a year-round supply of feedstock to biorefineries meanwhile serving an active management approach to reduce the risks associated with fire loss and microbial degradation. Wet logistics systems employ particle size reduction early in the supply chain through field-chopping which removes the dependency on drying corn stover prior to baling, expands the harvest window, and diminishes the biorefinery size reduction requirements. Over two harvest years, in-field forage chopping was capable of reducing over 60% of the corn stover to a particle size of 6 mm or less. Aerobic and anaerobic storage methods were evaluated for wet corn stover in 100 L laboratory reactors. Of the methods evaluated, traditional ensiling resulted in <6% total solid dry matter loss (DML, about five times less than the aerobic storage process and slightly less than half that of the anaerobic modified-Ritter pile method. To further demonstrate the effectiveness of the anaerobic storage, a field demonstration was completed with 272 dry tonnes of corn stover; DML averaged <5% after 6 months. Assessment of sugar release as a result of dilute acid or dilute alkaline pretreatment and subsequent enzymatic hydrolysis suggested that when anaerobic conditions were maintained in storage, sugar release was either similar to or greater than as-harvested material depending on the pretreatment chemistry used. This study demonstrates that wet logistics systems offer practical benefits for commercial corn stover supply, including particle size reduction during harvest, stability in storage, and compatibility with biochemical conversion of carbohydrates for biofuel production. Evaluation of the operational efficiencies and costs is suggested to quantify the potential benefits of a fully-wet biomass supply system to a commercial biorefinery.

  19. Effect of oil refining processes on 14 C-tetrachlorvinphos residues in soya bean oil

    International Nuclear Information System (INIS)

    Farghaly, M.; Zayed, S.M.A.D.

    1986-01-01

    Crude soya bean oil extracted from grains treated with 14 C-tetrachlorvinphos and stored for 30 weeks was subjected to different refining processes. The effect of commercial refining processes, namely: alkali treatment, bleaching, winterization and deodorization on the nature and magnitude of the originally present residues was investigated. A high percentage (52%) of the residues was eliminated during alkali neutralization. No potentially toxic materials were detected among the identified degradation products. The obtained data showed that the ultimate degradation products were dimethyl phosphate and mono methyl phosphate.2 tab.,2 scheme

  20. Effects of temperature and moisture on dilute-acid steam explosion pretreatment of corn stover and cellulase enzyme digestibility.

    Science.gov (United States)

    Tucker, Melvin P; Kim, Kyoung H; Newman, Mildred M; Nguyen, Quang A

    2003-01-01

    Corn stover is emerging as a viable feedstock for producing bioethanol from renewable resources. Dilute-acid pretreatment of corn stover can solubilize a significant portion of the hemicellulosic component and enhance the enzymatic digestibility of the remaining cellulose for fermentation into ethanol. In this study, dilute H2SO4 pretreatment of corn stover was performed in a steam explosion reactor at 160 degrees C, 180 degrees C, and 190 degrees C, approx 1 wt % H2SO4, and 70-s to 840-s residence times. The combined severity (Log10 [Ro] - pH), an expression relating pH, temperature, and residence time of pretreatment, ranged from 1.8 to 2.4. Soluble xylose yields varied from 63 to 77% of theoretical from pretreatments of corn stover at 160 and 180 degrees C. However, yields >90% of theoretical were found with dilute-acid pretreatments at 190 degrees C. A narrower range of higher combined severities was required for pretreatment to obtain high soluble xylose yields when the moisture content of the acidimpregnated feedstock was increased from 55 to 63 wt%. Simultaneous saccharification and fermentation (SSF) of washed solids from corn stover pretreated at 190 degrees C, using an enzyme loading of 15 filter paper units (FPU)/ g of cellulose, gave ethanol yields in excess of 85%. Similar SSF ethanol yields were found using washed solid residues from 160 and 180 degrees C pretreatments at similar combined severities but required a higher enzyme loading of approx 25 FPU/g of cellulose.

  1. Improving post-detonation energetics residues estimations for the Life Cycle Environmental Assessment process for munitions.

    Science.gov (United States)

    Walsh, Michael; Gullett, Brian; Walsh, Marianne; Bigl, Matthew; Aurell, Johanna

    2018-03-01

    The Life Cycle Environmental Assessment (LCEA) process for military munitions tracks possible environmental impacts incurred during all phases of the life of a munition. The greatest energetics-based emphasis in the current LCEA process is on manufacturing. A review of recent LCEAs indicates that energetics deposition on ranges from detonations and disposal during training is only peripherally examined through assessment of combustion products derived from closed-chamber testing or models. These assessments rarely report any measurable energetic residues. Field-testing of munitions for energetics residues deposition has demonstrated that over 30% of some energetic compounds remain after detonation, which conflicts with the LCEA findings. A study was conducted in the open environment to determine levels of energetics residue deposition and if combustion product results can be correlated with empirical deposition results. Energetics residues deposition, post-detonation combustion products, and fine aerosolized energetics particles following open-air detonation of blocks of Composition C4 (510 g RDX/block) were quantified. The deposited residues amounted to 3.6 mg of energetic per block of C4, or less than 0.001% of the original energetics. Aerial emissions of energetics were about 7% of the amount of deposited energetics. This research indicates that aerial combustion products analysis can provide a valuable supplement to energetics deposition data in the LCEA process but is insufficient alone to account for total residual energetics. This study demonstrates a need for the environmental testing of munitions to quantify energetics residues from live-fire training. Published by Elsevier Ltd.

  2. Environmental toxicity and radioactivity assessment of a titanium-processing residue with potential for environmental use.

    Science.gov (United States)

    Wendling, Laura A; Binet, Monique T; Yuan, Zheng; Gissi, Francesca; Koppel, Darren J; Adams, Merrin S

    2013-07-01

    Thorough examination of the physicochemical characteristics of a Ti-processing residue was undertaken, including mineralogical, geochemical, and radiochemical characterization, and an investigation of the environmental toxicity of soft-water leachate generated from the residue. Concentrations of most metals measured in the leachate were low; thus, the residue is unlikely to leach high levels of potentially toxic elements on exposure to low-ionic strength natural waters. Relative to stringent ecosystem health-based guidelines, only chromium concentrations in the leachate exceeded guideline concentrations for 95% species protection; however, sulfate was present at concentrations known to cause toxicity. It is likely that the high concentration of calcium and extreme water hardness of the leachate reduced the bioavailability of some elements. Geochemical modeling of the leachate indicated that calcium and sulfate concentrations were largely controlled by gypsum mineral dissolution. The leachate was not toxic to the microalga Chlorella sp., the cladoceran Ceriodaphnia dubia, or the estuarine bacterium Vibrio fischeri. The Ti-processing residue exhibited an absorbed dose rate of 186 nGy/h, equivalent to an annual dose of 1.63 mGy and an annual effective dose of 0.326 mGy. In summary, the results indicate that the Ti-processing residue examined is suitable for productive use as an environmental amendment following 10 to 100 times dilution to ameliorate potential toxic effects due to chromium or sulfate. Copyright © 2013 SETAC.

  3. Comparison between neutron diffraction measurements and numerical simulation of residual stresses of a wire-drawing process

    OpenAIRE

    Souza, Tomaz Fantin de; Soares, Carla Adriana Theis; Zottis, Juliana; Nunes, Rafael Menezes; Rocha, Alexandre da Silva; Hirsch, Thomas

    2013-01-01

    In this work, a drawing processed was simulated to calculate forces and the resulting residual stresses in the material. The calculated residual stresses were compared with experimentally measured residual stresses by the Neutron Diffraction Method. The modeled process was the Wire Drawing. The necessary parameters to model the process were taken from an industrial currently used process. Rods of an AISI 1045 steel with nominal diameters of 21.46 mm were reduced to 20.25 mm by drawing with an...

  4. Prevalence of antibiotic residues in commercial milk and its variation by season and thermal processing methods

    Directory of Open Access Journals (Sweden)

    Fathollah Aalipour

    2013-01-01

    Full Text Available Aims: In this study, the prevalence of antibiotic residues in pasteurized and sterilized commercial milk available in Shahre-kourd, Iran, was investigated. In addition, the influence of seasonal temperature changes on the prevalence of contamination was studied. Materials and Methods: Commercial milk samples of 187, including 154 pasteurized and 33 sterilized, milk samples were collected from the market between early January 2012 and late July of the same year. The presence of antibiotic residues was detected using the microbiological detection test kit, Eclipse 100, as a semi-quantitative method. Results: The results showed that 37 of the samples (19.8% have contained antibiotic residues above the European Union Maximum Residues Limits (EU-MRLs, of which 28 samples (14.97% were found to be contaminated but at the concentrations below the EU-MRLs. There was no significant difference between the contamination rate of pasteurized and Ultra High Temperature (UHT-sterilized samples. Similarly, variation of weather temperature with seasons had no effect on the contamination prevalence of milk samples ( P > 0.05. Conclusion: Based on the result of this study, antibiotics residues were present in the majority of milk samples. Neither the season nor the type of thermal processing of the commercial milks had noticeable impact on the prevalence level of the milk samples. However, an increasing trend of prevalence level for antibiotic residues was observed with increasing the temperature through the warm season.

  5. Effect of rice bran processing into oil on 14C-carbofuran residues

    International Nuclear Information System (INIS)

    Tayaputch, N.; Phaikaew, Y.; Sitayoung, R.

    1995-01-01

    The effects of processing rice bran into refined oil on 14 C-carbofuran residues were studied under field conditions and in fortified oil samples. The results showed that only 0.52% of the field applied 14 C-carbofuran was present in rice bran. Of this amount, crude oil retained 11.6%, compared to 86% in the fortified sample. When crude oils were subjected to degumming and neutralization processes, radioactivity substantially declined to 1% and 14% for aged and fortified residues, respectively. Bleaching and deodorization were ineffective in eliminating residues from spiked samples. Carbofuran, 3-hydroxy carbofuran, 3-keto carbofuran and carbofuran phenol, were identified in the crude and refined oils obtained from the field experiment. It is concluded that the commercially adopted procedures efficiently remove carbofuran and/or its products present in oil. (author). 4 refs, 5 tabs

  6. Comparison of Ultrasonic and CO2 Laser Pretreatment Methods on Enzyme Digestibility of Corn Stover

    Directory of Open Access Journals (Sweden)

    Li-Li Zuo

    2012-03-01

    Full Text Available To decrease the cost of bioethanol production, biomass recalcitrance needs to be overcome so that the conversion of biomass to bioethanol becomes more efficient. CO2 laser irradiation can disrupt the lignocellulosic physical structure and reduce the average size of fiber. Analyses with Fourier transform infrared spectroscopy, specific surface area, and the microstructure of corn stover were used to elucidate the enhancement mechanism of the pretreatment process by CO2 laser irradiation. The present work demonstrated that the CO2 laser had potential to enhance the bioconversion efficiency of lignocellulosic waste to renewable bioethanol. The saccharification rate of the CO2 laser pretreatment was significantly higher than ultrasonic pretreatment, and reached 27.75% which was 1.34-fold of that of ultrasonic pretreatment. The results showed the impact of CO2 laser pretreatment on corn stover to be more effective than ultrasonic pretreatment.

  7. Effect of xylanase, urea, Tween and Triton additives on bioethanol production of corn stover

    Science.gov (United States)

    Xin, Xiu; Lu, Jie; Yang, Rui-Feng; Song, Wen-jing; Li, Hai-ming; Wang, Hai-song; Zhou, Jing-hui

    2017-03-01

    Corn stover is a potential source of renewable biomass for conversion to bioethanol. Fed-batch semi-simultaneous saccharifcation and fermentation (S-SSF) of corn stover pretreated by liquid hot water (LHW) was investigated. The present study aimed to confirm the influence of xylanase, urea, Tween and Triton additives on bioethanol. Results show that the positive effect of xylanase, urea, Tween was observed. High ethanol concentration requires the addition of xylanase in the stage of saccharification. The optimal amount of xylanase was 0.2 g/g biomass and addition of Triton (Triton X-100) increases the effect of xylanase. Urea has a promotion effect on the whole fermentation process.When adding 0.1% urea in the fermentation stage,the best promoting rate is 24.2%. In the longitudinal comparison of the Tween series, under the same experimental conditions, the promoting effect of Tween series: Tween 40 > Tween 80 > Tween 20 > Tween 60.

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

    Science.gov (United States)

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

    2012-01-01

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

  9. Mobis HRH process residue hydroconversion using a recoverable nano-catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Romocki, S.; Rhodey, G. [Mobis Energy Inc., Calgary, AB (Canada)

    2009-07-01

    This presentation described a newly developed pseudo-homogeneous catalyst (PHC) for hydroconversion of heavy hydrocarbon feeds with high levels of sulphur, nitrogen, resins, asphaltenes and metals. An active catalyst is formed in the reaction system, consisting of particles that are 2-9 nm in size and whose properties resemble those of a colloid solution at both room and reaction temperature. Residue processing with this pseudo-homogeneous catalyst system results in better cracking and hydrogenation at lower process severity. The PHC system in heavy residue hydroconversion (HRH) process achieves up to 95 per cent residue conversion at pressures below 7.3 MPa, reaction temperatures between 400 to 460 degrees C, and with feed space velocity between 1 to 2 per hour, thus rendering the PHC catalyst system suitable for deep conversion of hydrocarbon residues. As much as 95 per cent of the catalyst can be recovered and regenerated within the process. Pilot plants are in operation for the hydroconversion of Athabasca vacuum bottoms using this technology. The use of the HRH process in oilsands and refinery operations were discussed along with comparative yields and economics. tabs., figs.

  10. Engineering, nutrient removal, and feedstock conversion evaluations of four corn stover harvest scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Hoskinson, Reed L.; Radtke, Corey W. [Idaho National Laboratory, P.O Box 1625, Idaho Falls, ID 83415-2210 (United States); Karlen, Douglas L. [USDA-ARS, National Soil Tilth Laboratory, Ames, IA 50011-3120 (United States); Birrell, Stuart J. [Iowa State University, Agricultural and Biosystems Engineering Department, Ames, IA 50011 (United States); Wilhelm, W.W. [USDA-ARS, Soil and Water Conservation Research Unit, Lincoln, NE 68583-0934 (United States)

    2007-02-15

    Crop residue has been identified as a near-term source of biomass for renewable fuel, heat, power, chemicals and other bio-materials. A prototype one-pass harvest system was used to collect residue samples from a corn (Zea mays L.) field near Ames, IA. Four harvest scenarios (low cut, high-cut top, high-cut bottom, and normal cut) were evaluated and are expressed as collected stover harvest indices (CSHI). High-cut top and high-cut bottom samples were obtained from the same plot in separate operations. Chemical composition, dilute acid pretreatment response, ethanol conversion yield and efficiency, and thermochemical conversion for each scenario were determined. Mean grain yield in this study (10.1 Mg ha{sup -1} dry weight) was representative of the average yield (10.0 Mg ha{sup -1}) for the area (Story County, IA) and year (2005). The four harvest scenarios removed 6.7, 4.9, 1.7, and 5.1 Mg ha{sup -1} of dry matter, respectively, or 0.60 for low cut, 0.66 for normal cut, and 0.61 for the total high-cut (top+bottom) scenarios when expressed as CSHI values. The macro-nutrient replacement value for the normal harvest scenario was $57.36 ha{sup -1} or $11.27 Mg{sup -1}. Harvesting stalk bottoms increased stover water content, risk of combine damage, estimated transportation costs, and left insufficient soil cover, while also producing a problematic feedstock. These preliminary results indicate harvesting stover (including the cobs) at a height of approximately 40 cm would be best for farmers and ethanol producers because of faster harvest speed and higher quality ethanol feedstock. (author)

  11. Effects on residual stresses of aluminum alloy LC4 by laser shock processing

    Science.gov (United States)

    Zhang, Yong-kang; Lu, Jin-zhong; Kong, De-jun; Yao, Hui-xue; Yang, Chao-jun

    2007-12-01

    The influences of processing parameters on laser-induced shock waves in metal components are discussed and analyzed. The effects of different parameters of laser shock processing (LSP) on residual stress of aerospace aluminum alloy LC4 were investigated. LSP was performed by using an Nd: glass phosphate laser with 23 ns pulse width and up to ~45 J pulse energy at power densities above GW/mm -2. Special attention is paid to the residual stresses from laser shock processing. Modification of microstructure, surface morphology by laser shock processing is also discussed. Results to date indicate that laser shock processing has great potential as a means of improving the mechanical performance of components.

  12. Lagrangian trajectories, residual currents and rectification process in the Northern Gulf of California

    Science.gov (United States)

    Rodríguez, Pablo Alonso; Carbajal, Noel; Rodríguez, Juan Heberto Gaviño

    2017-07-01

    Considering a semi-implicit approximation of the Coriolis terms, a numerical solution of the vertically integrated equations of motion is proposed. To test the two-dimensional numerical model, several experiments for the calculation of Euler, Stokes and Lagrange residual currents in the Gulf of California were carried out. To estimate the Lagrangian residual current, trajectories of particles were also simulated. The applied tidal constituents were M2, S2, K2, N2, K1, P1 and O1. At spring tides, strong tidal velocities occur in the northern half of the gulf. In this region of complex geometry, depths change from a few meter in the northern shelf zone to more than 3000 m in the southern part. In the archipelago region, the presence of islands alters amplitude and direction of tidal currents producing a rectification process which is reflected in a clockwise circulation around Tiburón Island in the Lagrangian residual current. The rectification process is explained by the superposition of the Euler and Stokes residual currents. Residual current patterns show several cyclonic and anticyclonic gyres in the Northern Gulf of California. Numerical experiments for individual and combinations of several tidal constituents revealed a large variability of Lagrangian trajectories.

  13. Leaching Behavior of Circulating Fluidised Bed MSWI Air Pollution Control Residue in Washing Process

    Directory of Open Access Journals (Sweden)

    Zhiliang Chen

    2016-09-01

    Full Text Available In this study, air pollution control (APC residue is conducted with water washing process to reduce its chloride content. A novel electrical conductivily (EC measurement method is proposed to monitor the dynamic change of chloride concentrations in leachate as well as the chloride content of the residue. The method equally applies to various washing processes with different washing time, liquid/solid ratio and washing frequency. The results show that washing effectively extracts chloride salts from APC residues, including those from circulating fluidized bed (CFB municipal solid waste incineration (MSWI. The most appropriate liquid/solid ratio and washing time in the first washing are found to be around 4 L water per kg of APC residue and 30 min, respectively, and washing twice is required to obtain maximum dissolution. The pH value is the major controlling factor of the heavy metals speciation in leachate, while chloride concentration also affects the speciation of Cd. Water washing causes no perceptible transfer of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs from the APC residue to leachate. The chloride concentration is strongly related with electrical conductivity (EC, as well as with the concentrations of calcium, sodium and potassium of washing water. Their regression analyses specify that soluble chloride salts and EC could act as an indirect indicator to monitor the change of chloride concentration and remaining chloride content, thus, contributing to the selection of the optimal washing conditions.

  14. Neutralization of residual antimicrobial processing chemicals in broiler carcass rinse for improved detection of Campylobacter

    Science.gov (United States)

    Campylobacter presence on broiler carcasses in the U.S. is regulated. Processors may apply antimicrobial processing aids as a spray or immersion to lower contamination on carcasses. In the U.S., broiler carcasses are generally sampled by whole carcass rinse and the potential exists for residual le...

  15. Residual stresses generated in F-522 steel by different machining processes

    International Nuclear Information System (INIS)

    Gracia-Navas, V.; Ferreres, I.; Maranon, J. A.; Garcia-Rosales, C.; Gil-Sevillano, J.

    2005-01-01

    Machining operations induce plastic deformation and heat generation in the near surface area of the machined part, giving rise to residual stresses. Depending on their magnitude and sign, these stresses can be detrimental or beneficial to the service life of the part. The final stress state depends on the machining process applied, as well as on the machining parameters. Therefore, the establishment of adequate machining guidelines requires the measurement of the residual stresses generated both at the surface and inside the material. in this work, the residual stresses generated in F-522 steel by two hard turning (conventional and laser assisted) and two grinding (production and finishing) processes were measured by X-ray diffraction. Additionally, depth profiles of the volume fraction of retained austenite, microstructure and nano hardness were obtained in order to correlate those results with the residual stress state obtained for each machining process. It has been observed that turning generates tensile stresses in the surface while grinding causes compressive stresses. Below the surface grinding generates weak tensile or nearly null stresses whereas turning generates strong compressive stresses. These results show that the optimum mechanising process (disregarding economical considerations) implies the combination of turning plus elimination of a small thickness by final grinding. (Author) 19 refs

  16. The soda-ash roasting of chromite ore processing residue for the reclamation of chromium

    Science.gov (United States)

    Antony, M. P.; Tathavadkar, V. D.; Calvert, C. C.; Jha, A.

    2001-12-01

    Sodium chromate is produced via the soda-ash roasting of chromite ore with sodium carbonate. After the reaction, nearly 15 pct of the chromium oxide remains unreacted and ends up in the waste stream, for landfills. In recent years, the concern over environmental pollution from hexavalent chromium (Cr6+) from the waste residue has become a major problem for the chromium chemical industry. The main purpose of this investigation is to recover chromium oxide present in the waste residue as sodium chromate. Cr2O3 in the residue is distributed between the two spinel solid solutions, Mg(Al,Cr)2O4 and γ-Fe2O3. The residue from the sodium chromate production process was analyzed both physically and chemically. The compositions of the mineral phases were determined by X-ray diffraction (XRD), scanning electron microscopy (SEM), and electron probe microanalysis (EPMA). The influence of alkali addition on the overall reaction rate is examined. The kinetics of the chromium extraction reaction resulting from the residue of the soda-ash roasting process under an oxidizing atmosphere is also investigated. It is shown that the experimental results for the roasting reaction can be best described by the Ginstling and Brounshtein (GB) equation for diffusion-controlled kinetics. The apparent activation energy for the roasting reaction was calculated to be between 85 and 90 kJ·mol-1 in the temperature range 1223 to 1473 K. The kinetics of leaching of Cr3+ ions using the aqueous phase from the process residue is also studied by treating the waste into acid solutions with different concentrations.

  17. Effect of corn stover concentration on rheological characteristics.

    Science.gov (United States)

    Pimenova, Natalia V; Hanley, Thomas R

    2004-01-01

    Corn stover, a well-known example of lignocellulosic biomass, is a potential renewable feed for bioethanol production. Dilute sulfuric acid pretreatment removes hemicellulose and makes the cellulose more susceptible to bacterial digestion. The rheologic properties of corn stover pretreated in such a manner were studied. The Power Law parameters were sensitive to corn stover suspension concentration becoming more non-Newtonian with slope n, ranging from 0.92 to 0.05 between 5 and 30% solids. The Casson and the Power Law models described the experimental data with correlation coefficients ranging from 0.90 to 0.99 and 0.85 to 0.99, respectively. The yield stress predicted by direct data extrapolation and by the Herschel-Bulkley model was similar for each concentration of corn stover tested.

  18. Effects of coffee processing residues on anaerobic microorganisms and corresponding digestion performance.

    Science.gov (United States)

    Rojas-Sossa, Juan Pablo; Murillo-Roos, Mariana; Uribe, Lidieth; Uribe-Lorio, Lorena; Marsh, Terence; Larsen, Niels; Chen, Rui; Miranda, Alberto; Solís, Kattia; Rodriguez, Werner; Kirk, Dana; Liao, Wei

    2017-12-01

    The objective of this study was to delineate the effects of different coffee processing residues on the anaerobic microbes and corresponding digestion performance. The results elucidated that mucilage-rich feed enhanced the accumulation of methanogens, which consequently led to better digestion performance of biogas production. Fifty percent more methane and up to 3 times more net energy (heat and electricity) output were achieved by the digestion of the mucilage-rich feed (M3). The microbial community and statistical analyses further elucidated that different residues in the feed had significant impact on microbial distribution and correspondingly influenced the digestion performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. N - Fixation of Soybean and Residual Effect from N - Fixation of Soybean to Rice Yield in Rice - Soybean Cropping System Using N - 15 Technique

    International Nuclear Information System (INIS)

    Yathaputanon, C.; Chaiwannakupt, P.; Prasartsrisuparb, J; Arayangul, T.

    1998-01-01

    A field experiment was conducted for long term rice-soybean cropping system at Chiang Mai Field Crop Research Center, to estimate nitrogen fixation of soybean and residual benefit of the soybean stover to a following rice crop. Nitrogen fixation was estimated in the soybean using 15 N dilution technique and non nodulated groundnut as a standard crop. To estimate the residual nitrogen benefit to the rice crop was calculated by nitrogen-15 yield of rice where the soybean stover was either removed or returned. In the first year soybean fixed 48.42% of their nitrogen which producing 50.31 KgN/ha. Residual effect of soybean stover returned was 36.72% of nitrogen in rice which equal 50.62 KgN/ha. come from the soybean returned (stover plus root and nodule under the ground where the soybean stover was returned). The residual nitrogen-15 in the second year was too low to detect. No nitrogen fertilizer applied to the following rice plot where the soybean stover was returned, grain dry matter yield were up to 12% (1 st year) and 27% (2 nd year) grater than in the plots where the soybean stover was removed produce the highest grain dry matter yield which were higher 14 - 29% than the plots where the soybean stover was removed

  20. Moisture Sorption Characteristics of Corn Stover and Big Bluestem

    OpenAIRE

    Karunanithy, C.; Muthukumarappan, K.; Donepudi, A.

    2013-01-01

    Moisture content is an important feedstock quality in converting it into energy through biochemical or thermochemical platforms. Knowledge of moisture sorption relationship is useful in drying and storage to preserve the quality of feedstocks. Moisture sorption isotherms for potential feedstocks such as corn stover and big bluestem are missing. EMC values of corn stover and big bluestem were determined using static gravimetric technique with saturated salt solutions (ERH 0.12–0.89) at differe...

  1. Evaluation of electricity generation from lignin residue and biogas in cellulosic ethanol production.

    Science.gov (United States)

    Liu, Gang; Bao, Jie

    2017-11-01

    This study takes the first insight on the rigorous evaluation of electricity generation based on the experimentally measured higher heating value (HHV) of lignin residue, as well as the chemical oxygen demand (COD) and biological oxygen demand (BOD 5 ) of wastewater. For producing one metric ton of ethanol fuel from five typical lignocellulose substrates, including corn stover, wheat straw, rice straw, sugarcane bagasse and poplar sawdust, 1.26-1.85tons of dry lignin residue is generated from biorefining process and 0.19-0.27tons of biogas is generated from anaerobic digestion of wastewater, equivalent to 4335-5981kWh and 1946-2795kWh of electricity by combustion of the generated lignin residue and biogas, respectively. The electricity generation not only sufficiently meets the electricity needs of process requirement, but also generates more than half of electricity surplus selling to the grid. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Thermogravimetric study of the pyrolysis of biomass residues from tomato processing industry

    Energy Technology Data Exchange (ETDEWEB)

    Mangut, V.; Sabio, E.; Ganan, J.; Gonzalez, J.F.; Ramiro, A.; Gonzalez, C.M.; Roman, S.; Al-Kassir, A. [Department of Chemical and Energy Engineering, University of Extremadura, Avda. de Elvas s/n, 06071 Badajoz (Spain)

    2006-01-15

    There is an increasing concern with the environmental problems associated with the increasing CO{sub 2}, NO{sub x} and SO{sub x} emissions resulting from the rising use of fossil fuels. Renewable energy, mainly biomass, can contribute to reduce the fossil fuels consumption. Biomass is a renewable resource with a widespread world distribution. Tomato processing industry produces a high amount of biomass residue (peel and seeds) that could be used for thermal energy and electricity. A characterization and thermogravimetric study has been carried out. The residue has a high HHV and volatile content, and a low ash, and S contents. A kinetic model has been developed based on the degradation of hemicellulose, cellulose, lignin and oil that describe the pyrolysis of peel, seeds and peel and seeds residues. (author)

  3. Reduction of tensile residual stresses during the drawing process of tungsten wires

    International Nuclear Information System (INIS)

    Rodriguez Ripoll, Manel; Weygand, Sabine M.; Riedel, Hermann

    2010-01-01

    Tungsten wires are commonly used in the lighting industry as filaments for lamps. During the drawing process, the inhomogeneous deformation imparted by the drawing die causes tensile residual stresses at the wire surface in circumferential direction. These stresses have a detrimental effect for the wire because they are responsible for driving longitudinal cracks, known as splits. This work proposes two methods for reducing the residual stresses during wire drawing, namely applying an advanced die geometry and performing an inexpensive post-drawing treatment based on targeted bending operations. These two methods are analyzed with finite element simulations using material parameters obtained by mechanical tests on tungsten wires at different temperatures as input data. The computed results predict a substantial reduction of the circumferential residual stresses, thus reducing the risk of splitting.

  4. Comprehensive Utilization of Filter Residue from the Preparation Process of Zeolite-Based Catalysts

    Directory of Open Access Journals (Sweden)

    Shu-Qin Zheng

    2016-05-01

    Full Text Available A novel utilization method of filter residue from the preparation process of zeolite-based catalysts was investigated. Y zeolite and a fluid catalytic cracking (FCC catalyst were synthesized from filter residue. Compared to the Y zeolite synthesized by the conventional method, the Y zeolite synthesized from filter residue exhibited better thermal stability. The catalyst possessed wide-pore distribution. In addition, the pore volume, specific surface area, attrition resistance were superior to those of the reference catalyst. The yields of gasoline and light oil increased by 1.93 and 1.48 %, respectively. At the same time, the coke yield decreased by 0.41 %. The catalyst exhibited better gasoline and coke selectivity. The quality of the cracked gasoline had been improved.

  5. Influence of the residual oxygen in the plasma immersion ion implantation (PI3) processing of materials

    International Nuclear Information System (INIS)

    Ueda, M.; Silva, A.R.; Mello, Carina B.; Silva, G.; Reuther, H.; Oliveira, V.S.

    2011-01-01

    In this work, we investigated the effects of the contaminants present in the vacuum chamber of the PI3 system, in particular, the residual oxygen, which results in the formation of the oxide compounds on the surface and hence is responsible for the high implantation energies required to achieve reasonably thick treated layers. We used a mass spectrometer (RGA) with a quadruple filter to verify the composition of the residual vacuum and pressure of the elements present in the chamber. Initially we found a high proportion of residual oxygen in a vacuum with a pressure of 1 × 10 −3 Pa. Minimizing the residual oxygen percentage in about 80%, by efficient cleaning of the chamber walls and by improving the gas feeding process, we mitigated the formation of oxides during the PI3 process. Therefore we achieved a highly efficient PI3 processing obtaining implanted layers reaching about 50 nm, even in cases such as an aluminum alloy, where is very difficult to nitrogen implant at low energies. We performed nitrogen PI3 treatment of SS304 and Al7075 using pulses of only 3 kV and 15 × 10 −6 s at 1 kHz with an operating pressure of 1 Pa.

  6. An analytical model to predict and minimize the residual stress of laser cladding process

    Science.gov (United States)

    Tamanna, N.; Crouch, R.; Kabir, I. R.; Naher, S.

    2018-02-01

    Laser cladding is one of the advanced thermal techniques used to repair or modify the surface properties of high-value components such as tools, military and aerospace parts. Unfortunately, tensile residual stresses generate in the thermally treated area of this process. This work focuses on to investigate the key factors for the formation of tensile residual stress and how to minimize it in the clad when using dissimilar substrate and clad materials. To predict the tensile residual stress, a one-dimensional analytical model has been adopted. Four cladding materials (Al2O3, TiC, TiO2, ZrO2) on the H13 tool steel substrate and a range of preheating temperatures of the substrate, from 300 to 1200 K, have been investigated. Thermal strain and Young's modulus are found to be the key factors of formation of tensile residual stresses. Additionally, it is found that using a preheating temperature of the substrate immediately before laser cladding showed the reduction of residual stress.

  7. Alcohol production from agricultural and forestry residues

    Energy Technology Data Exchange (ETDEWEB)

    Dale, L; Opilla, R; Surles, T

    1980-09-01

    Technologies available for the production of ethanol from whole corn are reviewed. Particular emphasis is placed on the environmental aspects of the process, including land utilization and possible air and water pollutants. Suggestions are made for technological changes intended to improve the economics of the process as well as to reduce some of the pollution from by-product disposal. Ethanol may be derived from renewable cellulosic substances by either enzymatic or acid hydrolysis of cellulose to sugar, followed by conventional fermentation and distillation. The use of two agricultural residues - corn stover (field stalks remaining after harvest) and straw from wheat crops - is reviewed as a cellulosic feedstock. Two processes have been evaluated with regard to environmental impact - a two-stage acid process developed by G.T. Tsao of Purdue University and an enzymatic process based on the laboratory findings of C.R. Wilke of the University of California, Berkeley. The environmental residuals expected from the manufacture of methyl and ethyl alcohols from woody biomass are covered. The methanol is produced in a gasification process, whereas ethanol is produced by hydrolysis and fermentation processes similar to those used to derive ethanol from cellulosic materials.

  8. Alcohol production from agricultural and forestry residues

    Energy Technology Data Exchange (ETDEWEB)

    Opilla, R.; Dale, L.; Surles, T.

    1980-05-01

    A variety of carbohydrate sources can be used as raw material for the production of ethanol. Section 1 is a review of technologies available for the production of ethanol from whole corn. Particular emphasis is placed on the environmental aspects of the process, including land utilization and possible air and water pollutants. Suggestions are made for technological changes intended to improve the economics of the process as well as to reduce some of the pollution from by-product disposal. Ethanol may be derived from renewable cellulosic substances by either enzymatic or acid hydrolysis of cellulose to sugar, followed by conventional fermentation and distillation. Section 2 is a review of the use of two agricultural residues - corn stover (field stalks remaining after harvest) and straw from wheat crops - as a cellulosic feedstock. Two processes have been evaluated with regard to environmental impact - a two-stage acid process developed by G.T. Tsao of Purdue University and an enzymatic process based on the laboratory findings of C.R. Wilke of the University of California, Berkeley. Section 3 deals with the environmental residuals expected from the manufacture of methyl and ethyl alcohols from woody biomass. The methanol is produced in a gasification process, whereas ethanol is produced by hydrolysis and fermentation processes similar to those used to derive ethanol from cellulosic materials.

  9. Assessment of Shock Pretreatment of Corn Stover Using the Carboxylate Platform.

    Science.gov (United States)

    Darvekar, Pratik; Holtzapple, Mark T

    2016-03-01

    Corn stover was pretreated with lime and shock, a mechanical process that uses a shockwave to alter the biomass structure. Two pretreatments (lime-only and lime + shock) were evaluated using enzymatic hydrolysis, batch mixed-culture fermentations, and continuous countercurrent mixed-culture fermentation. In a 120-h enzymatic hydrolysis, shock pretreatment increased the glucan digestibility of submerged lime pretreatment (SLP) corn stover by 3.5 % and oxidative lime pretreatment (OLP) corn stover by 2.5 %. The continuum particle distribution model (CPDM) was used to simulate a four-stage continuous countercurrent mixed-culture fermentation using empirical rate models obtained from simple batch experiments. The CPDM model determined that lime + shock pretreatment increased the total carboxylic acids yield by 28.5 % over lime-only pretreatment in a countercurrent fermentation with a volatile solids loading rate (VSLR) of 12 g/(L/day) and liquid retention time (LRT) of 30 days. In a semi-continuous countercurrent fermentation performed in the laboratory for 112 days with a VSLR of 1.875 g/(L day) and LRT of 16 days, lime + shock pretreatment increased the total carboxylic acid yield by 14.8 %. The experimental results matched closely with CPDM model predictions (4.05 % error).

  10. Integrated Production of Xylonic Acid and Bioethanol from Acid-Catalyzed Steam-Exploded Corn Stover.

    Science.gov (United States)

    Zhu, Junjun; Rong, Yayun; Yang, Jinlong; Zhou, Xin; Xu, Yong; Zhang, Lingling; Chen, Jiahui; Yong, Qiang; Yu, Shiyuan

    2015-07-01

    High-efficiency xylose utilization is one of the restrictive factors of bioethanol industrialization. However, xylonic acid (XA) as a new bio-based platform chemical can be produced by oxidation of xylose with microbial. So, an applicable technology of XA bioconversion was integrated into the process of bioethanol production. After corn stover was pretreated with acid-catalyzed steam-explosion, solid and liquid fractions were obtained. The liquid fraction, also named as acid-catalyzed steam-exploded corn stover (ASC) prehydrolyzate (mainly containing xylose), was catalyzed with Gluconobacter oxydans NL71 to prepare XA. After 72 h of bioconversion of concentrated ASC prehydrolyzate (containing 55.0 g/L of xylose), the XA concentration reached a peak value of 54.97 g/L, the sugar utilization ratio and XA yield were 94.08 and 95.45 %, respectively. The solid fraction was hydrolyzed to produce glucose with cellulase and then fermented with Saccharomyces cerevisiae NL22 to produce ethanol. After 18 h of fermentation of concentrated enzymatic hydrolyzate (containing 86.22 g/L of glucose), the ethanol concentration reached its highest value of 41.48 g/L, the sugar utilization ratio and ethanol yield were 98.72 and 95.25 %, respectively. The mass balance showed that 1 t ethanol and 1.3 t XA were produced from 7.8 t oven dry corn stover.

  11. Key amino acid residues for the endo-processive activity of GH74 xyloglucanase.

    Science.gov (United States)

    Matsuzawa, Tomohiko; Saito, Yuji; Yaoi, Katsuro

    2014-05-02

    Unlike endo-dissociative-xyloglucanases, Paenibacillus XEG74 is an endo-processive xyloglucanase that contains four unique tryptophan residues in the negative subsites (W61 and W64) and the positive subsites (W318 and W319), as indicated by three-dimensional homology modelling. Selective replacement of the positive subsite residues with alanine mutations reduced the degree of processive activity and resulted in the more endo-dissociative-activity. The results showed that W318 and W319, which are found in the positive subsites, are essential for processive degradation and are responsible for maintaining binding interactions with xyloglucan polysaccharide through a stacking effect. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  12. Effect of processing conditions on residual stress distributions by bead-on-plate welding after surface machining

    International Nuclear Information System (INIS)

    Ihara, Ryohei; Mochizuki, Masahito

    2014-01-01

    Residual stress is important factor for stress corrosion cracking (SCC) that has been observed near the welded zone in nuclear power plants. Especially, surface residual stress is significant for SCC initiation. In the joining processes of pipes, butt welding is conducted after surface machining. Residual stress is generated by both processes, and residual stress distribution due to surface machining is varied by the subsequent butt welding. In previous paper, authors reported that residual stress distribution generated by bead on plate welding after surface machining has a local maximum residual stress near the weld metal. The local maximum residual stress shows approximately 900 MPa that exceeds the stress threshold for SCC initiation. Therefore, for the safety improvement of nuclear power plants, a study on the local maximum residual stress is important. In this study, the effect of surface machining and welding conditions on residual stress distribution generated by welding after surface machining was investigated. Surface machining using lathe machine and bead on plate welding with tungsten inert gas (TIG) arc under various conditions were conducted for plate specimens made of SUS316L. Then, residual stress distributions were measured by X-ray diffraction method (XRD). As a result, residual stress distributions have the local maximum residual stress near the weld metal in all specimens. The values of the local maximum residual stresses are almost the same. The location of the local maximum residual stress is varied by welding condition. It could be consider that the local maximum residual stress is generated by same generation mechanism as welding residual stress in surface machined layer that has high yield stress. (author)

  13. Residue dissipation and processing factor for dimethomorph, famoxadone and cymoxanil during raisin preparation.

    Science.gov (United States)

    Shabeer T P, Ahammed; Banerjee, Kaushik; Jadhav, Manjusha; Girame, Rushali; Utture, Sagar; Hingmire, Sandip; Oulkar, Dasharath

    2015-03-01

    A method was validated for the simultaneous analysis of the residues of dimethomorph, famoxadone and cymoxanil in grape and raisin matrix by ethyl acetate based extraction and liquid chromatography tandem mass spectrometric analysis. Field studies were conducted to evaluate the dissipation rate kinetics and processing factor (PF) for these pesticides during raisin making. Residue data during the drying process were best fitted to 1st+1st order rate kinetics with half-life ranging between 8-9 days for dimethomorph, 12-13 days for famoxadone and 9-10 days for cymoxanil at single dose (SD) and double dose (DD), respectively. PF values calculated were 1.03 and 1.14 for dimethomorph, 1.95 and 2.09 for famoxadone, and 1.99 and 1.35 for cymoxanil at SD and DD, respectively. PF value >1 indicates concentration of the residues during raisin making. The residues of detected pesticides in market samples of raisins were devoid of any risk of acute toxicity related to dietary exposure. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Characterization and extraction of volatile compounds from pineapple (Ananas comosus L. Merril processing residues

    Directory of Open Access Journals (Sweden)

    Lília Calheiros de Oliveira Barretto

    2013-12-01

    Full Text Available The aim of this study was to extract and identify volatile compounds from pineapple residues generated during concentrated juice processing. Distillates of pineapple residues were obtained using the following techniques: simple hydrodistillation and hydrodistillation by passing nitrogen gas. The volatile compounds present in the distillates were captured by the solid-phase microextraction technique. The volatile compounds were identified in a system of high resolution gas chromatography system coupled with mass spectrometry using a polyethylene glycol polar capillary column as stationary phase. The pineapple residues constituted mostly of esters (35%, followed by ketones (26%, alcohols (18%, aldehydes (9%, acids (3% and other compounds (9%. Odor-active volatile compounds were mainly identified in the distillate obtained using hydrodistillation by passing nitrogen gas, namely decanal, ethyl octanoate, acetic acid, 1-hexanol, and ketones such as γ-hexalactone, γ-octalactone, δ-octalactone, γ-decalactone, and γ-dodecalactone. This suggests that the use of an inert gas and lower temperatures helped maintain higher amounts of flavor compounds. These data indicate that pineapple processing residue contained important volatile compounds which can be extracted and used as aroma enhancing products and have high potential for the production of value-added natural essences.

  15. Optimization of the Process Parameters for Controlling Residual Stress and Distortion in Friction Stir Welding

    DEFF Research Database (Denmark)

    Tutum, Cem Celal; Schmidt, Henrik Nikolaj Blicher; Hattel, Jesper Henri

    2008-01-01

    In the present paper, numerical optimization of the process parameters, i.e. tool rotation speed and traverse speed, aiming minimization of the two conflicting objectives, i.e. the residual stresses and welding time, subjected to process-specific thermal constraints in friction stir welding......, is investigated. The welding process is simulated in 2-dimensions with a sequentially coupled transient thermo-mechanical model using ANSYS. The numerical optimization problem is implemented in modeFRONTIER and solved using the Multi-Objective Genetic Algorithm (MOGA-II). An engineering-wise evaluation or ranking...

  16. Residual neural processing of musical sound features in adult cochlear implant users

    DEFF Research Database (Denmark)

    Timm, Lydia; Vuust, Peter; Brattico, Evira

    2014-01-01

    Auditory processing in general and music perception in particular are hampered in adult cochlear implant (CI) users. To examine the residual music perception skills and their underlying neural correlates in CI users implanted in adolescence or adulthood, we conducted an electrophysiological...... neural skills for music processing even in CI users who have been implanted in adolescence or adulthood. HIGHLIGHTS: -Automatic brain responses to musical feature changes reflect the limitations of central auditory processing in adult Cochlear Implant users.-The brains of adult CI users automatically......: auditory evoked potentials; cochlear implant; mismatch negativity; music multi-feature paradigm; music perception...

  17. Research on statistical process control for solvent residual quantity of packaging materials

    Science.gov (United States)

    Xiao, Yingzhe; Huang, Yanan

    2013-03-01

    Statistical Process Control (SPC) and the basic tool of its controlling - control chart - are discussed in this paper based on the development of quality management, current situation of quality management of Chinese packaging enterprises, and the necessity of applying SPC. On this basis, X-R control chart is used to analyze and control the solvent residual in the compound process. This work may allow field personnel to find the shortcomings in the quality control by noticing the corresponding of fluctuations and slow variations in the process in time. In addition, SPC also provides objective basis for the quality management personnel to assess semi-products or products quality.

  18. Effect of handling and processing on pesticide residues in food- a review.

    Science.gov (United States)

    Bajwa, Usha; Sandhu, Kulwant Singh

    2014-02-01

    Pesticides are one of the major inputs used for increasing agricultural productivity of crops. The pesticide residues, left to variable extent in the food materials after harvesting, are beyond the control of consumer and have deleterious effect on human health. The presence of pesticide residues is a major bottleneck in the international trade of food commodities. The localization of pesticides in foods varies with the nature of pesticide molecule, type and portion of food material and environmental factors. The food crops treated with pesticides invariably contain unpredictable amount of these chemicals, therefore, it becomes imperative to find out some alternatives for decontamination of foods. The washing with water or soaking in solutions of salt and some chemicals e.g. chlorine, chlorine dioxide, hydrogen peroxide, ozone, acetic acid, hydroxy peracetic acid, iprodione and detergents are reported to be highly effective in reducing the level of pesticides. Preparatory steps like peeling, trimming etc. remove the residues from outer portions. Various thermal processing treatments like pasteurization, blanching, boiling, cooking, steaming, canning, scrambling etc. have been found valuable in degradation of various pesticides depending upon the type of pesticide and length of treatment. Preservation techniques like drying or dehydration and concentration increase the pesticide content many folds due to concentration effect. Many other techniques like refining, fermentation and curing have been reported to affect the pesticide level in foods to varied extent. Milling, baking, wine making, malting and brewing resulted in lowering of pesticide residue level in the end products. Post harvest treatments and cold storage have also been found effective. Many of the decontamination techniques bring down the concentration of pesticides below MRL. However, the diminution effect depends upon the initial concentration at the time of harvest, substrate/food and type of

  19. Optimisation of process parameters in friction stir welding based on residual stress analysis: a feasibility study

    DEFF Research Database (Denmark)

    Tutum, Cem Celal; Hattel, Jesper Henri

    2010-01-01

    The present paper considers the optimisation of process parameters in friction stir welding (FSW). More specifically, the choices of rotational speed and traverse welding speed have been investigated using genetic algorithms. The welding process is simulated in a transient, two......-dimensional sequentially coupled thermomechanical model in ANSYS. This model is then used in an optimisation case where the two objectives are the minimisation of the peak residual stresses and the maximisation of the welding speed. The results indicate that the objectives for the considered case are conflicting......, and this is presented as a Pareto optimal front. Moreover, a higher welding speed for a fixed rotational speed results, in general, in slightly higher stress levels in the tension zone, whereas a higher rotational speed for a fixed welding speed yields somewhat lower peak residual stress, however, a wider tension zone...

  20. Drawing a Transductive Ecosophy in Process: Technological Arts, Residual Matter, Associated Milieus

    Directory of Open Access Journals (Sweden)

    Gisèle Trudel

    2015-06-01

    Full Text Available Drawing a Transductive Ecosophy in Process: Technological Arts, Residual Matter, Associated Milieus by Gisèle Trudel. NANO: New American Notes Online, Issue 7: The Aesthetics of Trash - nanocrit.com. This text examines the tetralogy of media artworks about residual matter produced by Ælab between 2008 and 2014. Taking its own title as a diagram (Deleuze and Guattari Mille Plateaux, it charts and builds on the processes of these artworks, elucidating their relations to materiality, philosophy and technicity. Technological research-creation becomes in these instances a transdisciplinary aesthetic act, emerging from an ecology of practices that combine humans, non-humans and waste matter in an effort to increase attentiveness in actions.

  1. Effect of residual H2O2 from advanced oxidation processes on subsequent biological water treatmen : A laboratory batch study

    NARCIS (Netherlands)

    Wang, F.; van Halem, D.; Liu, G.; Lekkerkerker-Teunissen, K.; van der Hoek, J.P.

    2017-01-01

    H2O2 residuals from advanced oxidation processes (AOPs) may have critical impacts on the microbial ecology and performance of subsequent biological treatment processes, but little is known. The objective of this study was to evaluate how H2O2 residuals influence sand systems with an emphasis on

  2. Effect of Chitin Extraction Processes on Residual Antimicrobials in Shrimp Shells

    OpenAIRE

    Uno, Kazuaki; Higashioto, Yoshifumi; Chaweepack, Tidaporn; Ruangpan, Lila

    2014-01-01

    The present study examined the influences of industrial chitin extraction processes on the residual oxytetracycline (OTC) and oxolinic acid (OA) in shrimp carapaces and shells. The drugs were orally administered by catheter to the kuruma shrimp (Penaeus japonicus) and vannamei shrimp (Penaeus vannamei). The shrimps were sampled at 6-h post-dosing and their carapaces and shells were collected and used as raw material in the chitin extraction. Residua...

  3. Residual stress evaluation and curvature behavior of aluminum 7050 peen forming processed

    International Nuclear Information System (INIS)

    Oliveira, Rene Ramos de

    2011-01-01

    Shot peening is a superficial cold work process used to increase the fatigue life evaluated by residual stress measurements. The peen forming process is a variant of the shot peening process, where a curvature in the plate is obtained by the compression of the grains near to the surface. In this paper, the influence of the parameters such as: pressure of shot, ball shot size and thickness of aluminum 7050 samples with respect to residual stress profile and resulting arc height was studied. The evaluation of the residual stress profile was obtained by sin 2 ψ method. The results show that the formation of the curvature arc height is proportional to the shot peening pressure, of spheres size and inversely proportional to the thickness of the sample, and that stress concentration factor is larger for samples shot peened with small balls. On final of this paper presents an additional study on micro strain and average crystallite size, which can evaluate the profile of the samples after blasting. (author)

  4. Conversion of plutonium scrap and residue to boroilicate glass using the GMODS process

    International Nuclear Information System (INIS)

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.; Rudolph, J.; Elam, K.R.; Ferrada, J.J.

    1995-01-01

    Plutonium scrap and residue represent major national and international concerns because (1) significant environmental, safety, and health (ES ampersand H) problems have been identified with their storage; (2) all plutonium recovered from the black market in Europe has been from this category; (3) storage costs are high; and (4) safeguards are difficult. It is proposed to address these problems by conversion of plutonium scrap and residue to a CRACHIP (CRiticality, Aerosol, and CHemically Inert Plutonium) glass using the Glass Material Oxidation and Dissolution System (GMODS). CRACHIP refers to a set of requirements for plutonium storage forms that minimize ES ampersand H concerns. The concept is several decades old. Conversion of plutonium from complex chemical mixtures and variable geometries into a certified, qualified, homogeneous CRACHIP glass creates a stable chemical form that minimizes ES ampersand H risks, simplifies safeguards and security, provides an easy-to-store form, decreases storage costs, and allows for future disposition options. GMODS is a new process to directly convert metals, ceramics, and amorphous solids to glass; oxidize organics with the residue converted to glass; and convert chlorides to borosilicate glass and a secondary sodium chloride stream. Laboratory work has demonstrated the conversion of cerium (a plutonium surrogate), uranium (a plutonium surrogate), Zircaloy, stainless steel, and other materials to glass. GMODS is an enabling technology that creates new options. Conventional glassmaking processes require conversion of feeds to oxide-like forms before final conversion to glass. Such chemical conversion and separation processes are often complex and expensive

  5. Long-term no-till and stover retention each decrease the global warming potential of irrigated continuous corn.

    Science.gov (United States)

    Jin, Virginia L; Schmer, Marty R; Stewart, Catherine E; Sindelar, Aaron J; Varvel, Gary E; Wienhold, Brian J

    2017-07-01

    Over the last 50 years, the most increase in cultivated land area globally has been due to a doubling of irrigated land. Long-term agronomic management impacts on soil organic carbon (SOC) stocks, soil greenhouse gas (GHG) emissions, and global warming potential (GWP) in irrigated systems, however, remain relatively unknown. Here, residue and tillage management effects were quantified by measuring soil nitrous oxide (N 2 O) and methane (CH 4 ) fluxes and SOC changes (ΔSOC) at a long-term, irrigated continuous corn (Zea mays L.) system in eastern Nebraska, United States. Management treatments began in 2002, and measured treatments included no or high stover removal (0 or 6.8 Mg DM ha -1  yr -1 , respectively) under no-till (NT) or conventional disk tillage (CT) with full irrigation (n = 4). Soil N 2 O and CH 4 fluxes were measured for five crop-years (2011-2015), and ΔSOC was determined on an equivalent mass basis to ~30 cm soil depth. Both area- and yield-scaled soil N 2 O emissions were greater with stover retention compared to removal and for CT compared to NT, with no interaction between stover and tillage practices. Methane comprised <1% of total emissions, with NT being CH 4 neutral and CT a CH 4 source. Surface SOC decreased with stover removal and with CT after 14 years of management. When ΔSOC, soil GHG emissions, and agronomic energy usage were used to calculate system GWP, all management systems were net GHG sources. Conservation practices (NT, stover retention) each decreased system GWP compared to conventional practices (CT, stover removal), but pairing conservation practices conferred no additional mitigation benefit. Although cropping system, management equipment/timing/history, soil type, location, weather, and the depth to which ΔSOC is measured affect the GWP outcomes of irrigated systems at large, this long-term irrigated study provides valuable empirical evidence of how management decisions can impact soil GHG emissions and surface

  6. The effectiveness of sewage treatment processes to remove faecal pathogens and antibiotic residues

    Science.gov (United States)

    Hendricks, Rahzia; Pool, Edmund John

    2012-01-01

    Pathogens and antibiotics enter the aquatic environment via sewage effluents and may pose a health risk to wild life and humans. The aim of this study was to determine the levels of faecal bacteria, and selected antibiotic residues in raw wastewater and treated sewage effluents from three different sewage treatment plants in the Western Cape, South Africa. Sewage treatment plant 1 and 2 use older technologies, while sewage treatment plant 3 has been upgraded and membrane technologies were incorporated in the treatment processes. Coliforms and Escherichia coli (E. coli) were used as bioindicators for faecal bacteria. A chromogenic test was used to screen for coliforms and E. coli. Fluoroquinolones and sulfamethoxazole are commonly used antibiotics and were selected to monitor the efficiency of sewage treatment processes for antibiotic removal. Enzyme Linked Immunosorbent Assays (ELISAs) were used to quantitate antibiotic residues in raw and treated sewage. Raw intake water at all treatment plants contained total coliforms and E. coli. High removal of E. coli by treatment processes was evident for treatment plant 2 and 3 only. Fluoroquinolones and sulfamethoxazole were detected in raw wastewater from all sewage treatment plants. Treatment processes at plant 1 did not reduce the fluoroquinolone concentration in treated sewage effluents. Treatment processes at plant 2 and 3 reduced the fluoroquinolone concentration by 21% and 31%, respectively. Treatment processes at plant 1 did not reduce the sulfamethoxazole concentration in treated sewage effluents. Treatment processes at plant 2 and 3 reduced sulfamethoxazole by 34% and 56%, respectively. This study showed that bacteria and antibiotic residues are still discharged into the environment. Further research needs to be undertaken to improve sewage treatment technologies, thereby producing a better quality treated sewage effluent. PMID:22242882

  7. Production of crude enzyme from Aspergillus nidulans AKB-25 using black gram residue as the substrate and its industrial applications

    Directory of Open Access Journals (Sweden)

    Amit Kumar

    2016-06-01

    Full Text Available The production of crop residues in India is estimated to be about 500–550 million tons annually. It is estimated that about 93 million tons of crop residues is burnt annually which is not only wastage of valuable biomass resources but pollution of the environment with the production of green house gases also. Among different low cost crop residues, black gram residue as the substrate produced maximal endoglucanase, FPase, and β-glucosidase activities from Aspergillus nidulans AKB-25 under solid-state fermentation. During optimisation of cultural parameters A. nidulans AKB-25 produced maximal endoglucanase (152.14 IU/gds, FPase (3.42 FPU/gds and xylanase (2441.03 IU/gds activities. The crude enzyme was found effective for the saccharification of pearl millet stover and bio-deinking of mixed office waste paper. The crude enzyme from A. nidulans AKB-25 produced maximum fermentable sugars of 546.91 mg/g from alkali-pretreated pearl millet stover by saccharification process at a dose of 15 FPU/g of substrate. Pulp brightness and deinking efficiency of mixed office waste paper improved by 4.6% and 25.01% respectively and mitigated dirt counts by 74.70% after bio-deinking. Physical strength properties like burst index, tensile index and double fold number were also improved during bio-deinking of mixed office waste paper.

  8. Bio-gasification of post transesterified microalgae residues: A route to improving overall process renewabilities

    DEFF Research Database (Denmark)

    Ehimen, Ehiazesebhor Augustine

    Using results from experiments and process modelling tools, a renewability assessment was carried out for the use of the conventional and in-situ transesterification processes for a large scale microalgae biodiesel production. In a present day scenario, all the transesterification processes were...... shown to be non-renewable. The process renewability of biodiesel production from microalgae was found to significantly improve with the use of renewable electricity, reacting alcohols from biomass fermentation and process heating and biomass drying using heat from wood pellet combustion or heat pump...... technology. The anaerobic digestion of the microalgae residues to generate methane from was further seen to lead to positive renewabilities for the considered microalgae-biodiesel processes....

  9. Flexible process options for the immobilisation of residues and wastes containing plutonium

    International Nuclear Information System (INIS)

    Stewart, M.W.A.; Moricca, S.A.; Day, R. A.; Begg, B. D.; Scales, C. R.; Maddrell, E. R.; Eilbeck, A. B.

    2007-01-01

    Residues and waste streams containing plutonium present unique technical, safety, regulatory, security, and socio-political challenges. In the UK these streams range from lightly plutonium contaminated materials (PCM) through to residue s resulting directly from Pu processing operations. In addition there are potentially stocks of Pu oxide powders whose future designation may be either a waste or an asset, due to their levels of contamination making their reuse uneconomic, or to changes in nuclear policy. While waste management routes exist for PCM, an immobilisation process is required for streams containing higher levels of Pu. Such a process is being developed by Nexia Solutions and ANSTO to treat and immobilise Pu waste and residues currently stored on the Sellafield site. The characteristics of these Pu waste streams are highly variable. The physical form of the Pu waste ranges from liquids, sludges, powders/granules, to solid components (e.g., test fuels), with the Pu present as an ion in solution, as a salt, metal, oxide or other compound. The chemistry of the Pu waste streams also varies considerably with a variety of impurities present in many waste streams. Furthermore, with fissile isotopes present, criticality is an issue during operations and in the store or repository. Safeguards and security concerns must be assessed and controlled. The process under development, by using a combination of tailored waste form chemistry combined with flexible process technology aims to develop a process line to handle a broad range of Pu waste streams. It aims to be capable of dealing with not only current arisings but those anticipated to arise as a result of future operations or policy changes. (authors)

  10. Analysis of fabrication process for AP1000 passive residual heat removal heat exchanger

    International Nuclear Information System (INIS)

    Gao Yongjun

    2011-01-01

    This paper introduces the design parameters of the passive residual heat removal heat exchanger for American advanced passive pressurized water reactor (AP1000), describes the fabrication process for the head, tubesheet, heat exchange tube, corrugated plate and support frame assembly of the heat exchanger, mainly in terms of material, forging, welding, and heat treatment, and also analyzes the crucial steps for the support frame assembling, tubesheet plate welding, tube penetration welding of C tube bundle, closure/head welding, heat treatment, hydraulic (pressure) test, and etc. in the process of heat exchanger assembling. (author)

  11. Vertical Distribution of Structural Components in Corn Stover

    Directory of Open Access Journals (Sweden)

    Jane M. F. Johnson

    2014-11-01

    Full Text Available In the United States, corn (Zea mays L. stover has been targeted for second generation fuel production and other bio-products. Our objective was to characterize sugar and structural composition as a function of vertical distribution of corn stover (leaves and stalk that was sampled at physiological maturity and about three weeks later from multiple USA locations. A small subset of samples was assessed for thermochemical composition. Concentrations of lignin, glucan, and xylan were about 10% greater at grain harvest than at physiological maturity, but harvestable biomass was about 25% less due to stalk breakage. Gross heating density above the ear averaged 16.3 ± 0.40 MJ kg−1, but with an alkalinity measure of 0.83 g MJ−1, slagging is likely to occur during gasification. Assuming a stover harvest height of 10 cm, the estimated ethanol yield would be >2500 L ha−1, but it would be only 1000 L ha−1 if stover harvest was restricted to the material from above the primary ear. Vertical composition of corn stover is relatively uniform; thus, decision on cutting height may be driven by agronomic, economic and environmental considerations.

  12. Vertical distribution of structural components in corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Jane M. F. Johnson; Douglas L. Karlen; Garold L. Gresham; Keri B. Cantrell; David W. Archer; Brian J. Wienhold; Gary E. Varvel; David A. Laird; John Baker; Tyson E. Ochsner; Jeff M. Novak; Ardell D. Halvorson; Francisco Arriaga; David T. Lightle; Amber Hoover; Rachel Emerson; Nancy W. Barbour

    2014-11-01

    In the United States, corn (Zea mays L.) stover has been targeted for second generation fuel production and other bio-products. Our objective was to characterize sugar and structural composition as a function of vertical distribution of corn stover (leaves and stalk) that was sampled at physiological maturity and about three weeks later from multiple USA locations. A small subset of samples was assessed for thermochemical composition. Concentrations of lignin, glucan, and xylan were about 10% greater at grain harvest than at physiological maturity, but harvestable biomass was about 25% less due to stalk breakage. Gross heating density above the ear averaged 16.3 ± 0.40 MJ kg?¹, but with an alkalinity measure of 0.83 g MJ?¹, slagging is likely to occur during gasification. Assuming a stover harvest height of 10 cm, the estimated ethanol yield would be >2500 L ha?¹, but it would be only 1000 L ha?¹ if stover harvest was restricted to the material from above the primary ear. Vertical composition of corn stover is relatively uniform; thus, decision on cutting height may be driven by agronomic, economic and environmental considerations.

  13. Integrated bioethanol production from mixtures of corn and corn stover.

    Science.gov (United States)

    Chen, Sitong; Xu, Zhaoxian; Li, Xiujuan; Yu, Jianming; Cai, Mufeng; Jin, Mingjie

    2018-02-27

    Conversion of lignocellulosic biomass, such as corn stover (CS), to ethanol has encountered issues of inhibition from degradation products, low ethanol titer and low ethanol productivity. This work integrated CS into corn ethanol process for effective conversion. CS was pretreated using either dilute alkali or dilute acid pretreatment. The pretreated CS was enzymatically hydrolyzed and then mixed with liquefied corn for ethanol fermentation. Fermentation strains, substrate mixing ratios and fed-batch strategy were investigated. The mixture of alkali pretreated CS and corn at solids loadings of 10% and 20%, respectively, resulted in 92.30 g/L ethanol. Ethanol titer was further improved to 96.43 g/L with a fed-batch strategy. The mixture of dilute acid pretreated CS and corn achieved a better performance, leading to 104.9 g/L ethanol with 80.47% ethanol yield and a productivity as high as 2.19 g/L/h. This work demonstrated effective conversion of CS and corn together to ethanol. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Allelic Variation in Outer Membrane Protein A and Its Influence on Attachment of Escherichia coli to Corn Stover

    Directory of Open Access Journals (Sweden)

    Chunyu Liao

    2017-05-01

    Full Text Available Understanding the genetic factors that govern microbe-sediment interactions in aquatic environments is important for water quality management and reduction of waterborne disease outbreaks. Although chemical properties of bacteria have been identified that contribute to initiation of attachment, the outer membrane proteins that contribute to these chemical properties still remain unclear. In this study we explored the attachment of 78 Escherichia coli environmental isolates to corn stover, a representative agricultural residue. Outer membrane proteome analysis led to the observation of amino acid variations, some of which had not been previously described, in outer membrane protein A (OmpA at 10 distinct locations, including each of the four extracellular loops, three of the eight transmembrane segments, the proline-rich linker and the dimerization domain. Some of the polymorphisms within loops 1, 2, and 3 were found to significantly co-occur. Grouping of sequences according to the outer loop polymorphisms revealed five distinct patterns that each occur in at least 5% of our isolates. The two most common patterns, I and II, are encoded by 33.3 and 20.5% of these isolates and differ at each of the four loops. Statistically significant differences in attachment to corn stover were observed among isolates expressing different versions of OmpA and when different versions of OmpA were expressed in the same genetic background. Most notable was the increased corn stover attachment associated with a loop 3 sequence of SNFDGKN relative to the standard SNVYGKN sequence. These results provide further insight into the allelic variation of OmpA and implicate OmpA in contributing to attachment to corn stover.

  15. Profiling the effects of process changes on residual host cell proteins in biotherapeutics by mass spectrometry.

    Science.gov (United States)

    Schenauer, Matthew R; Flynn, Gregory C; Goetze, Andrew M

    2013-01-01

    An advanced liquid chromatography/mass spectrometry (MS) platform was used to identify and quantify residual Escherichia coli host cell proteins (HCPs) in the drug substance (DS) of several peptibodies (Pbs). Significantly different HCP impurity profiles were observed among different biotherapeutic Pbs as well as one Pb purified via multiple processes. The results can be rationally interpreted in terms of differences among the purification processes, and demonstrate the power of this technique to sensitively monitor both the quantity and composition of residual HCPs in DS, where these may represent a safety risk to patients. The breadth of information obtained using MS is compared to traditional multiproduct enzyme-linked immunosorbent assay (ELISA) values for total HCP in the same samples and shows that, in this case, the ELISA failed to detect multiple HCPs. The HCP composition of two upstream samples was also analyzed and used to demonstrate that HCPs that carry through purification processes to be detectable in DS are not always among those that are the most abundant upstream. Compared to ELISA, we demonstrate that MS can provide a more comprehensive, and accurate, characterization of DS HCPs, thereby facilitating process development as well as more rationally assessing potential safety risks posed by individual, identified HCPs. © 2013 American Institute of Chemical Engineers.

  16. Optimizing biomass feedstock logistics for forest residue processing and transportation on a tree-shaped road network

    Science.gov (United States)

    Hee Han; Woodam Chung; Lucas Wells; Nathaniel Anderson

    2018-01-01

    An important task in forest residue recovery operations is to select the most cost-efficient feedstock logistics system for a given distribution of residue piles, road access, and available machinery. Notable considerations include inaccessibility of treatment units to large chip vans and frequent, long-distance mobilization of forestry equipment required to process...

  17. Evaluation of an Anaerobic Digestion System for Processing CELSS Crop Residues for Resource Recovery

    Science.gov (United States)

    Strayer, R. F.; Finger, B. W.; Alazraki, M. P.

    1997-01-01

    Three bioreactors, connected in series, were used to process CELSS potato residues for recovery of resources. The first stage was an anaerobic digestor (8 L working volume; cow rumen contents inoculum; fed-batch; 8 day retention time; feed rate 25 gdw/day) that converted 33% of feed (dry weight loss) to CO2 and "volatile fatty acids" (vfa, 83:8:8 mmolar ratio acetic:propionic:butyric). High nitrate-N in the potato residue feed was absent in the anaerobic effluent, with a high portion converted to NH4(+)-N and the remainder unaccounted and probably lost to denitrification and NH4(+) volatilization. Liquid anaerobic effluent was fed to an aerobic, yeast biomass production vessel (2 L volume; Candida ingens inoculum; batch [pellicle] growth; 2 day retention time) where the VFAs and some NH4(+)-N were converted into yeast biomass. Yeast yields accounted for up to 8% of potato residue fed into the anaerobic bioreactor. The third bioreactor (0.5 L liquid working volume; commercial nitrifier inoculum; packed-bed biofilm; continuous yeast effluent feed; recirculating; constant volume; 2 day hydraulic retention time) was used to convert successfully the remaining NH4(+)-N into nitrate-N (preferred form of N for CELSS crop production) and to remove the remaining degradable soluble organic carbon. Effluents from the last two stages were used for partial replenishment of minerals for hydroponic potato production.

  18. Effect of Refining Processes on Magnitude and Nature of Malathion and Carbofuran Residues in Cotton Seed Oil

    International Nuclear Information System (INIS)

    Zayed, S.M.A.D.; Farghaly, M.; Mahdy, F.

    2005-01-01

    Cotton seeds obtained from 14 C-carbofuran or 14 C-malathion-treated plants contained 0.25% and 0.11% of the originally applied radioactivity, respectively. The concentration of malathion residues in oil, methanol soluble and in the seed cake amounted to 0.94, 2.6 and 1.7 ppm, respectively. Commercial processing procedures led to a gradual decrease in the total amount of 14 C-residues in oils with aged residues as well as in oil fortified with the radiolabelled insecticides. The refined oil contained only about 20% of the 14 C-residues originally present. The major residue in processed oil contained malathion, malathion monocarboxylic acid and alpha-(O,O-dimethyl phosphorodithio)-propionic acid. The concentration of 14 C-carbofuran residues in cotton seed oil, methanol extract and cake was 1.7, 12.3 and 2.4 ppm, respectively. The main residues in the oil were carbofuran and its phenol. The methanol solubles contained conjugated metabolites, which upon hydrolysis gave 3-hydroxy-carbofuran as a major product. Refinement reduced the residue in oil to 0.26 ppm. The residue in refined oil contained carbofuran and carbofuran phenol as main constituents together with smaller amounts of 3-hydroxy- and 3-keto carbofuran

  19. Fungal cellulase/xylanase production and corresponding hydrolysis using pretreated corn stover as substrates.

    Science.gov (United States)

    Zhang, Liang; Wang, Xiaoqing; Ruan, Zhenhua; Liu, Ying; Niu, Xiaorui; Yue, Zhengbo; Li, Zhimin; Liao, Wei; Liu, Yan

    2014-01-01

    Three pretreated corn stover (ammonia fiber expansion, dilute acid, and dilute alkali) were used as carbon source to culture Trichoderma reesei Rut C-30 for cellulase and xylanase production. The results indicated that the cultures on ammonia fiber expansion and alkali pretreated corn stover had better enzyme production than the acid pretreated ones. The consequent enzymatic hydrolysis was performed applying fungal enzymes on pretreated corn stover samples. Tukey's statistical comparisons exhibited that there were significant differences on enzymatic hydrolysis among different combination of fungal enzymes and pretreated corn stover. The higher sugar yields were achieved by the enzymatic hydrolysis of dilute alkali pretreated corn stover.

  20. Characterisation of non-degraded oligosaccharides in enzymatically hydrolysed and fermented, dilute ammonia-pretreated corn stover for ethanol production.

    Science.gov (United States)

    Jonathan, M C; DeMartini, J; Van Stigt Thans, S; Hommes, R; Kabel, M A

    2017-01-01

    Corn stover is lignocellulosic biomass that has potential to be used as raw material for bioethanol production. In the current research, dilute ammonia pretreatment was used to improve the accessibility of corn stover carbohydrates to subsequently added hydrolytic enzymes. Some carbohydrates, however, were still present after enzymatic hydrolysis and fermentation. Hence, this research was aimed to characterise the recalcitrant carbohydrates, especially the oligosaccharides that remained after hydrolysis and fermentation of dilute ammonia-pretreated corn stover (DACS). About 35% (w/w) of DACS carbohydrates remained after enzymatic hydrolysis and fermentation of the released monosaccharides. One-third of these recalcitrant carbohydrates were water soluble and composed of diverse oligosaccharides. By using UHPLC-MS n , more than 50 oligosaccharides were detected. Glucurono-xylooligosaccharides (UAXOS) with a degree of polymerisation (DP) less than 5 were the most abundant oligosaccharides. The (4- O -methyl) glucuronosyl substituent was mostly attached onto the terminal xylosyl residue. It was shown that the glucuronosyl substituent in some UAXOS was modified into a hexenuronosyl, a glucuronamide or a hexenuronamide residue due to the dilute ammonia pretreatment. Another group of abundant oligosaccharides comprised various xyloglucan oligosaccharides (XGOS), with a DP 5 annotated as XXG as the most pronounced. In addition, disaccharides annotated as xylosyl-glucose with different β linkages as well as larger carbohydrates were present in the fermentation slurry. Around one-third of the 35% (w/w) recalcitrant DACS carbohydrates remained as water-soluble saccharides. In this study, more than 50 recalcitrant oligosaccharides were detected, which mostly composed of xylosyl and/or glucosyl residues. The most pronounced oligosaccharides were UAXOS and XGOS. Hence, α-glucuronidase and α-xylosidase were suggested to be added to the enzyme mixture to degrade these

  1. Environmental Impacts of Stover Removal in the Corn Belt

    Energy Technology Data Exchange (ETDEWEB)

    Alicia English; Wallace E. Tyner; Juan Sesmero; Phillip Owens; David Muth

    2012-08-01

    When considering the market for biomass from corn stover resources erosion and soil quality issues are important to consider. Removal of stover can be beneficial in some areas, especially when coordinated with other conservation practices, such as vegetative barrier strips and cover crops. However, benefits are highly dependent on several factors, namely if farmers see costs and benefits associated with erosion and the tradeoffs with the removal of biomass. This paper uses results from an integrated RUSLE2/WEPS model to incorporate six different regime choices, covering management, harvest and conservation, into simple profit maximization model to show these tradeoffs.

  2. Study and utilization of residual sludges rich in alumina from an anodizing process

    International Nuclear Information System (INIS)

    Carranza, Carlos; Montero, Mavis L.; Rodriguez, Ventura

    2006-01-01

    Residual sludges from a process of anodizing were studied by x-ray diffraction as part of research into alternative materials for the chemical industry. The sludge containing mainly bayerite Al(OH) 3 and bohemite AlO(OH). The phases of α and β alumina were identified at 700 degrees, corundum phase is present at 850 degrees. Zeolite A is synthesized from these and by means of hydrothermal, which was identified by X-ray diffraction. Scanning microscopy of zeolite A shows a high degree of crystallinity. (author) [es

  3. Extraction of Iron and Manganese from Pyrolusite Absorption Residue by Ammonium Sulphate Roasting–Leaching Process

    Directory of Open Access Journals (Sweden)

    Lin Deng

    2018-01-01

    Full Text Available The residue from desulfurization and denitrification of exhaust gas treatment process with pyrolusite ore as absorbent is regarded as a potential source of iron and manganese. In this study, an extraction process is proposed for recovery of iron and manganese with ammonium sulphate roasting followed by sulphuric acid leaching. Firstly, the conversion mechanism was analyzed through mineral phase analysis of roasting products at different roasting temperature by means of X-ray diffraction (XRD technology. Then, the parameters of the roasting procedure such as roasting temperature and time, ammonium sulphate dosage, leaching temperature, leaching time, and sulphuric acid concentration are examined. The results implicate that the iron oxide and manganese dioxide in the residue are firstly converted into the water-soluble ( NH 4 3 Fe ( SO 4 3 and ( NH 4 2 Mn 2 ( SO 4 3 at 200–350 °C, and then the more stable NH 4 Fe ( SO 4 2 and MnSO 4 are formed, at temperature higher than 350 °C. Under optimum conditions, 95.2% Fe and 97.0% Mn can be extracted. Reactant diffusion through inert layer of silicon dioxide was considered as the rate-limiting step for iron extraction with an activation energy of 20.56 kJ/mol, while, the recovery process of Mn was controlled by both reactant diffusion and chemical reaction with an activation energy of 29.52 kJ/mol.

  4. Illinois biomass resources: annual crops and residues; canning and food-processing wastes. Preliminary assessment

    Energy Technology Data Exchange (ETDEWEB)

    Antonopoulos, A A

    1980-06-01

    Illinois, a major agricultural and food-processing state, produces vast amounts of renewable plant material having potential for energy production. This biomass, in the form of annual crops, crop residues, and food-processing wastes, can be converted to alternative fuels (such as ethanol) and industrial chemicals (such as furfural, ethylene, and xylene). The present study provides a preliminary assessment of these Illinois biomass resources, including (a) an appraisal of the effects of their use on both agriculture and industry; (b) an analysis of biomass conversion systems; and (c) an environmental and economic evaluation of products that could be generated from biomass. It is estimated that, of the 39 x 10/sup 6/ tons of residues generated in 1978 in Illinois from seven main crops, about 85% was collectible. The thermal energy equivalent of this material is 658 x 10/sup 6/ Btu, or 0.66 quad. And by fermenting 10% of the corn grain grown in Illinois, some 323 million gallons of ethanol could have been produced in 1978. Another 3 million gallons of ethanol could have been produced in the same year from wastes generated by the state's food-processing establishments. Clearly, Illinois can strengthen its economy substantially by the development of industries that produce biomass-derived fuels and chemicals. In addition, a thorough evaluation should be made of the potential for using the state's less-exploitable land for the growing of additional biomass.

  5. Winery solid residue revalorization into oil and antioxidant with nutraceutical properties by an enzyme assisted process.

    Science.gov (United States)

    Tobar, P; Moure, A; Soto, C; Chamy, R; Zúñiga, M E

    2005-01-01

    Revalorization of the winery industry residue, grape seed is studied for the production of an oil and defatted meal with nutraceutical properties. Conventional grape seed oil extraction process is carried out by pressing at high temperature affecting the product quality. Oil extraction by cold pressing improves product quality, but it gives a low oil yield. Oil extracted is increased at the pressing stage, when an enzymatic pre-treatment is incorporated in to the conventional process. The yield is determined by determining the residual oil in the pressed cake. Using an enzymatic treatment during 9 hours at 45 degrees C and 50% of moisture, with a mixture of two commercial enzymes grape seed oil extraction yield by cold pressing is raised up to 72%, being a 59.4% increment in comparison to the yield obtained by the control, without enzymes. The defatted meal by enzimatic assisted process improves its phenolic compounds between 2 and 4 times, depending on the conditions of phenolics extraction in comparison to the control samples.

  6. Processing of removed Scholven residue in liquid phase at 600 atm

    Energy Technology Data Exchange (ETDEWEB)

    Reitz

    1942-02-26

    This report listed data of the preliminary hydrogenation and gasolinification of anhydrogenous and phenol-less S-middle oil obtained from processing Scholven residue in liquid phase. A petrol was produced, at 250 atm with catalyst 8376/6434, that had practically the same naphthene. It had a slightly higher aromatic content than compound petrol obtained from the preliminary hydrogenation and gasolinification step (8376/6434) of the processing of Scholven S-middle oil. This petrol's octane number was 1.5 units higher than that of the compound petrol. Comments point out that the difference was more noticeable when the associated liquid-phase petrols were mixed. The report then described the process in detail, including a table with all the relevant data. 1 table.

  7. Distribution of multiple pesticide residues in apple segments after home processing

    DEFF Research Database (Denmark)

    Rasmussen, Rie Romme; Poulsen, Mette Erecius; Hansen, H. C. B.

    2003-01-01

    The effects of washing, storing, boiling, peeling, coring and juicing on pesticide residue were investigated for field-sprayed Discovery and Jonagold apples. Residues of chlorpyrifos, cypermethrin, deltamethrin, diazinon, endosulfan, endosulfan sulfate, fenitrothion, fenpropathrin, iprodione...... significantly reduced five of the pesticide residues: diazinon, chlorpyrifos, fenitrothion, kresoxim-methyl and tolylfluanid, by 25-69%. Residues of the metabolite endosulfan sulfate were increased by 34% during storage. Boiling significantly reduced residues of fenitrothion and tolylfluanid by 32 and 81...

  8. Optimization of biofuel production from corn stover under supply uncertainty in Ontario

    Directory of Open Access Journals (Sweden)

    Jonathan Ranisau

    2017-12-01

    Full Text Available In this paper, a biofuel production supply chain optimization framework is developed that can supply the fuel demand for 10% of Ontario. Different biomass conversion technologies are considered, such as pyrolysis and gasification and subsequent hydro processing and the Fischer-Tropsch process. A supply chain network approach is used for the modeling, which enables the optimization of both the biorefinery locations and the associated transportation networks. Gasification of corn stover is examined to convert waste biomass into valuable fuel. Biomass-derived fuel has several advantages over traditional fuels including substantial greenhouse gas reduction, generating higher quality synthetic fuels, providing a use for biomass waste, and potential for use without much change to existing infrastructure. The objective of this work is to show the feasibility of the use of corn stover as a biomass feedstock to a hydrocarbon biofuel supply chain in Ontario using a mixed-integer linear programming model while accounting for the uncertainty in the availability of corn stover. In the case study, the exact number of biorefineries is left as a policy decision and the optimization is carried out over a range of the possible numbers of facilities. The results obtained from the case study suggests implementing gasification technology followed by Fischer-Tropsch at two different sites in Ontario. The optimal solution satisfied 10% of the yearly fuel demand of Ontario with two production plants (14.8 billion L of fuel and requires an investment of $42.9 billion, with a payback period of about 3 years.

  9. Structural and chemical analysis of process residue from biochemical conversion of wheat straw (Triticum aestivum L.) to ethanol

    DEFF Research Database (Denmark)

    Hansen, Mads Anders Tengstedt; Jørgensen, Henning; Laursen, Kristian Holst

    2013-01-01

    Biochemical conversion of lignocellulose to fermentable carbohydrates for ethanol production is now being implemented in large-scale industrial production. Applying hydrothermal pretreatment and enzymatic hydrolysis for the conversion process, a residue containing substantial amounts of lignin...

  10. Modeling the Influence of Process Parameters and Additional Heat Sources on Residual Stresses in Laser Cladding

    Science.gov (United States)

    Brückner, F.; Lepski, D.; Beyer, E.

    2007-09-01

    In laser cladding thermal contraction of the initially liquid coating during cooling causes residual stresses and possibly cracks. Preweld or postweld heating using inductors can reduce the thermal strain difference between coating and substrate and thus reduce the resulting stress. The aim of this work is to better understand the influence of various thermometallurgical and mechanical phenomena on stress evolution and to optimize the induction-assisted laser cladding process to get crack-free coatings of hard materials at high feed rates. First, an analytical one-dimensional model is used to visualize the most important features of stress evolution for a Stellite coating on a steel substrate. For more accurate studies, laser cladding is simulated including the powder-beam interaction, the powder catchment by the melt pool, and the self-consistent calculation of temperature field and bead shape. A three-dimensional finite element model and the required equivalent heat sources are derived from the results and used for the transient thermomechanical analysis, taking into account phase transformations and the elastic-plastic material behavior with strain hardening. Results are presented for the influence of process parameters such as feed rate, heat input, and inductor size on the residual stresses at a single bead of Stellite coatings on steel.

  11. Evaluation of certain crop residues for carbohydrate and protein fractions by cornell net carbohydrate and protein system

    Directory of Open Access Journals (Sweden)

    Venkateswarulu Swarna

    2015-06-01

    Full Text Available Four locally available crop residues viz., jowar stover (JS, maize stover (MS, red gram straw (RGS and black gram straw (BGS were evaluated for carbohydrate and protein fractions using Cornell Net Carbohydrate and Protein (CNCP system. Lignin (% NDF was higher in legume straws as compared to cereal stovers while Non-structural carbohydrates (NSC (% DM followed the reverse trend. The carbohydrate fractions A and B1 were higher in BGS while B2 was higher in MS as compared to other crop residues. The unavailable cell wall fraction (C was higher in legume straws when compared to cereal stovers. Among protein fractions, B1 was higher in legume straws when compared to cereal stovers while B2 was higher in cereal stovers as compared to legume straws. Fraction B3 largely, bypass protein was highest in MS as compared to other crop residues. Acid detergent insoluble crude protein (ADICP (% CP or unavailable protein fraction C was lowest in MS and highest in BGS. It is concluded that MS is superior in nutritional value for feeding ruminants as compared to other crop residues.

  12. Monitoring EDTA process residuals in recombinant protein manufacturing using liquid chromatography.

    Science.gov (United States)

    Lin, Miao-Fang; Royal, Mabel; Hayenga, Kirk; Conn, Greg

    2003-07-25

    We have developed a chromatographic method for the high sensitivity quantitation of EDTA process residuals in recombinant protein manufacturing validation studies. The reversed-phase HPLC method is based upon the detection of Cu(2+)/EDTA complexes at 254 nm, and has been qualified for use on intermediates from a purification process for a recombinant protein expressed in E. coli. Quantitation of EDTA in recombinant protein process intermediates is linear in the range of 0.2 to 64 microM with LOD/LOQ values below 2.0 microM. The assay is suitable for use in process backgrounds containing Tris, HEPES, MES, NaCl, hexanediol, NH(4)SO(4), and PEG. EDTA spike recovery values in all process samples tested were greater than 90% at the 4.0 microM concentration. System suitability parameters for the chromatographic method were developed based upon peak area and retention time precision, column efficiency and USP tailing. Peak area precision and intermediate precision values across the linear range of the assay exhibited C.V. values less than 15% at any concentration tested in all sample backgrounds. The assay robustness was tested by transfer of the assay to a second laboratory and analyst with use of multiple process intermediate lots, reagent/column lots, and HPLC systems.

  13. Residual neural processing of musical sound features in adult cochlear implant users

    Directory of Open Access Journals (Sweden)

    Lydia eTimm

    2014-04-01

    Full Text Available AbstractAuditory processing in general and music perception in particular are hampered in adult Cochlear Implant (CI users. To examine the residual music perception skills and their underlying neural correlates in CI users implanted in adolescence or adulthood, we conducted an electrophysiological and behavioural study comparing adult CI users with normal-hearing age-matched controls (NH controls. We used a newly developed musical multi-feature paradigm, which makes it possible to test automatic auditory discrimination of six different types of sound feature changes inserted within a musical enriched setting lasting only 20 minutes. The presentation of stimuli did not require the participants’ attention, allowing the study of the early automatic stage of feature processing in the auditory cortex. For the CI users, we obtained mismatch negativity (MMN brain responses to five feature changes but not to changes of rhythm, whereas we obtained MMNs for all the feature changes in the NH controls. Furthermore, the MMNs to Deviants of pitch of CI users were reduced in amplitude and later than those of NH controls for changes of pitch and guitar timbre. No other group differences in MMN parameters were found to changes in intensity and saxophone timbre. Furthermore, the MMNs in CI users reflected the behavioral scores from a respective discrimination task and were correlated with patients’ age and speech intelligibility. Our results suggest that even though CI users are not performing at the same level as NH controls in neural discrimination of pitch-based features, they do possess potential neural abilities for music processing. However, CI users showed a disrupted ability to automatically discriminate rhythmic changes compared with controls. The current behavioural and MMN findings highlight the residual neural skills for music processing even in CI users who have been implanted in adolescence or adulthood.

  14. Sustainability of corn stover harvest strategies in Pennsylvania

    Science.gov (United States)

    Paul R. Adler; Benjamin M. Rau; Gregory W. Roth

    2015-01-01

    Pennsylvania farmers have a long history of harvesting corn (Zea mays L.) stover after grain harvest for animal bedding and feed or as a component of mushroom compost, or as silage for dairy cattle feed. With the shallow soils and rolling topography, soil erosion and carbon losses have been minimized through extensive use of cover crops, no-till, and...

  15. Fuel ethanol production from alkaline peroxide pretreated corn stover

    Science.gov (United States)

    Corn stover (CS) has the potential to serve as an abundant low-cost feedstock for production of fuel ethanol. Due to heterogeneous complexity and recalcitrance of lignocellulosic feedstocks, pretreatment is required to break the lignin seal and/or disrupt the structure of crystalline cellulose to in...

  16. Corn stover-enhanced cellulase production by Aspergillus niger ...

    African Journals Online (AJOL)

    The production of extracellular cellulases by Aspergilus niger NRRL 567 on corn stover was studied in liquid state fermentation. In this study, three cellulases, exoglucanase (EXG), endoglucanase (EG) and β-glucosidase (BGL) were produced by A. niger NRRL 567. The optimal pH, temperature and incubation time for ...

  17. Characterization of substituents in xylans from corn cobs and stover

    NARCIS (Netherlands)

    Dongen, van F.E.M.; Eylen, van D.; Kabel, M.A.

    2011-01-01

    Structural knowledge on hemicellulose from corn cobs and stover is helpful to better understand their position within the plant cell wall architecture as well as their enzymatic saccharification. In this research different extracts were prepared with water, 1 M and 4 M alkali. Most of the xylans

  18. Volume 11 No. 1 February 2011 4538 UTILIZATION OF STOVER ...

    African Journals Online (AJOL)

    user

    2011-02-01

    Feb 1, 2011 ... Liveweight changes (LWC) varied between 6 g/d weight loss by sheep on UGA-2 fodder and 46 g/d in ... fed as sole diets or supplements to WAD sheep, and the cultivars ranked in decreasing order of stover quality as: ..... non-lactating Red Sokoto goats in the subhumid zone of Nigeria. Anim. Sci. J.,. 2003 ...

  19. Mechanical Characterization of Thermomechanical Matrix Residual Stresses Incurred During MMC Processing

    Science.gov (United States)

    Castelli, Michael G.

    1998-01-01

    In recent years, much effort has been spent examining the residual stress-strain states of advanced composites. Such examinations are motivated by a number of significant concerns that affect composite development, processing, and analysis. The room-temperature residual stress states incurred in many advanced composite systems are often quite large and can introduce damage even prior to the first external mechanical loading of the material. These stresses, which are induced during the cooldown following high-temperature consolidation, result from the coefficient of thermal expansion mismatch between the fiber and matrix. Experimental techniques commonly used to evaluate composite internal residual stress states are non-mechanical in nature and generally include forms of x-ray and neutron diffraction. Such approaches are usually complex, involving a number of assumptions and limitations associated with a wide range of issues, including the depth of penetration, the volume of material being assessed, and erroneous effects associated with oriented grains. Furthermore, and more important to the present research, these techniques can assess only "single time" stress in the composite. That is, little, if any, information is obtained that addresses the time-dependent point at which internal stresses begin to accumulate, the manner in which the accumulation occurs, and the presiding relationships between thermoelastic, thermoplastic, and thermoviscous behaviors. To address these critical issues, researchers at the NASA Lewis Research Center developed and implemented an innovative mechanical test technique to examine in real time, the time-dependent thermomechanical stress behavior of a matrix alloy as it went through a consolidation cycle.

  20. Valorization of lignin and cellulose in acid-steam-exploded corn stover by a moderate alkaline ethanol post-treatment based on an integrated biorefinery concept.

    Science.gov (United States)

    Yang, Sheng; Zhang, Yue; Yue, Wen; Wang, Wei; Wang, Yun-Yan; Yuan, Tong-Qi; Sun, Run-Cang

    2016-01-01

    Due to the unsustainable consumption of fossil resources, great efforts have been made to convert lignocellulose into bioethanol and commodity organic compounds through biological methods. The conversion of cellulose is impeded by the compactness of plant cell wall matrix and crystalline structure of the native cellulose. Therefore, appropriate pretreatment and even post-treatment are indispensable to overcome this problem. Additionally, an adequate utilization of coproduct lignin will be important for improving the economic viability of modern biorefinery industries. The effectiveness of moderate alkaline ethanol post-treatment on the bioconversion efficiency of cellulose in the acid-steam-exploded corn stover was investigated in this study. Results showed that an increase of the alcoholic sodium hydroxide (NaOH) concentration from 0.05 to 4% led to a decrease in the lignin content in the post-treated samples from 32.8 to 10.7%, while the cellulose digestibility consequently increased. The cellulose conversion of the 4% alcoholic NaOH integrally treated corn stover reached up to 99.3% after 72 h, which was significantly higher than that of the acid steam exploded corn stover without post-treatment (57.3%). In addition to the decrease in lignin content, an expansion of cellulose I lattice induced by the 4% alcoholic NaOH post-treatment played a significant role in promoting the enzymatic hydrolysis of corn stover. More importantly, the lignin fraction (AL) released during the 4% alcoholic NaOH post-treatment and the lignin-rich residue (EHR) remained after the enzymatic hydrolysis of the 4% alcoholic NaOH post-treated acid-steam-exploded corn stover were employed to synthesize lignin-phenol-formaldehyde (LPF) resins. The plywoods prepared with the resins exhibit satisfactory performances. An alkaline ethanol system with an appropriate NaOH concentration could improve the removal of lignin and modification of the crystalline structure of cellulose in acid

  1. Residual stress evaluation and curvature behavior of aluminum 7050 peen forming processed; Avaliacao da tensao residual em aluminio 7050 conformado pelo processo peen forming

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Rene Ramos de

    2011-07-01

    Shot peening is a superficial cold work process used to increase the fatigue life evaluated by residual stress measurements. The peen forming process is a variant of the shot peening process, where a curvature in the plate is obtained by the compression of the grains near to the surface. In this paper, the influence of the parameters such as: pressure of shot, ball shot size and thickness of aluminum 7050 samples with respect to residual stress profile and resulting arc height was studied. The evaluation of the residual stress profile was obtained by sin{sup 2} {psi} method. The results show that the formation of the curvature arc height is proportional to the shot peening pressure, of spheres size and inversely proportional to the thickness of the sample, and that stress concentration factor is larger for samples shot peened with small balls. On final of this paper presents an additional study on micro strain and average crystallite size, which can evaluate the profile of the samples after blasting. (author)

  2. Nutritive Value Assessment of Four Crop Residues by Proximate ...

    African Journals Online (AJOL)

    Dr Grace Tona

    The results revealed that citrus pulp and maize stover could be of higher nutritional value in ruminants feed than bean waste, while rice husk was lowest. Keywords: Crop residues, in vitro incubation, West African Dwarf goats. Introduction. The livestock industry in Nigeria has contributed substantially to the national wealth.

  3. A process for treatment of residues from dry/semidry APC systems at municipal solid waste incinerators. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hjelmar, O. [VKI, Hoersholm (Denmark)] Holland, D. [FLS miljoe a/s, Valby (Denmark)] Poulsen, B. [KARA, Roskilde (Denmark)

    1997-08-01

    The main objective of the project has been to establish and test a process for treatment of residues from the semidry (and dry) lime injection based APC processes at MSWIs, which will ensure that the residues can be managed in an environmentally safe manner. In pursuit of this goal, the following activities have been carried out: Performance of pilot scale extractions (approximately 50 kg of residue per batch) at the KARA MSWI in Roskilde of semidry APC system residues in order to establish and optimize process conditions. The optimization includes consideration of the possibilities for subsequent treatment/stabilization of the extracted solid phase as well as the possibility of treatment and safe discharge/utilization of the extract; Performance of chemical characterization, hydrogeochemical model calculations and experimental work in order to improve the understanding of the mechanisms and factors which for several contaminants control the equilibrium between the solid and liquid phases, both in the short and the long germ, and to use this information to obtain an environmentally acceptable method for stabilization/treatment of the extracted residues while at the same time minimizing the necessary amount of additives; production of treated residues and performance of leaching tests on these to assess and demonstrate the effectiveness of the entire process (extraction + stabilization/treatment); Evaluation of the technical, economical and environmental consequences of full scale implementation of the process. (EG) EFP-94. 19 refs.

  4. Cellulosic Biomass Sugars to Advantaged Jet Fuel – Catalytic Conversion of Corn Stover to Energy Dense, Low Freeze Point Paraffins and Naphthenes

    Energy Technology Data Exchange (ETDEWEB)

    Cortright, Randy [Virent, Inc., Madison, WI (United States)

    2015-07-31

    The purpose of this project was to demonstrate the technical and commercial feasibility of producing liquid fuels, particularly jet fuel, from lignocellulosic materials, such as corn stover. This project was led by Virent, Inc. (Virent) which has developed a novel chemical catalytic process (the BioForming® platform) capable of producing “direct replacement” liquid fuels from biomass-derived feedstocks. Virent has shown it is possible to produce an advantaged jet fuel from biomass that meets or exceeds specifications for commercial and military jet fuel through Fuel Readiness Level (FRL) 5, Process Validation. This project leveraged The National Renewable Energy Lab’s (NREL) expertise in converting corn stover to sugars via dilute acid pretreatment and enzymatic hydrolysis. NREL had previously developed this deconstruction technology for the conversion of corn stover to ethanol. In this project, Virent and NREL worked together to condition the NREL generated hydrolysate for use in Virent’s catalytic process through solids removal, contaminant reduction, and concentration steps. The Idaho National Laboratory (INL) was contracted in this project for the procurement, formatting, storage and analysis of corn stover and Northwestern University developed fundamental knowledge of lignin deconstruction that can help improve overall carbon recovery of the combined technologies. Virent conducted fundamental catalytic studies to improve the performance of the catalytic process and NREL provided catalyst characterization support. A technoeconomic analysis (TEA) was conducted at each stage of the project, with results from these analyses used to inform the direction of the project.

  5. 77 FR 50661 - Notice of Filing of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or...

    Science.gov (United States)

    2012-08-22

    ... enforcement of tolerances in plants. Quantitation is by GC using a GC/nitrogen-specific detector (GC/NPD) for... as the sum of cis- and trans-isomers, in or on corn, sweet, stover from 4.5 ppm to 25.0 ppm... appropriate sensitivity in the raw crop and processed commodities for sweet corn stover for which an increase...

  6. Modelling of thermal processes during extrusion based densification of agricultural biomass residues

    International Nuclear Information System (INIS)

    Mikulandrić, Robert; Vermeulen, Brecht; Nicolai, Bart; Saeys, Wouter

    2016-01-01

    Highlights: • Thermal models have been coupled in finite element modelling program for process analysis. • Process has been simulated based on available model parameters from literature. • Model has been validated based on measurement data from field tests. • Heat losses during biomass densification have been estimated to be 10–25%. • Suggestions for process improvement have been proposed. - Abstract: Biomass residues are increasing their share as a feedstock for renewable heat and power systems. Agricultural biomass is available in large quantities but to be utilised in energy systems the bulk density of the material should be increased. A large number of process parameters influence biomass compression and thus affect machinery efficiency and particular energy consumption. Increased concerns related to energy efficiency and environmental impacts of agricultural machinery have led to an increased interest in simulation models which can be used for process optimisation. In this study the influence of temperature on the biomass compression process performance has been analysed. For this purpose, mathematical models describing the thermal processes in the biomass material and the surrounding compression chamber have been elaborated. The heat transfer in the biological material has been described with time dependent Navier–Stokes equations for non-isothermal flow, while time dependent Navier–Stokes equations for heat transfer in solids have been utilised to describe heat transfer in metal structures of the chamber. The prediction performance of the model has been verified by comparing the simulated temperature evolution in the biomass and chamber walls to the corresponding values measured from a biomass compression machine through dedicated tests. The model was found to be able to predict the measured values with an average R 2 of 0.82. The influence of friction heat in the compression chamber has been simulated and heat losses during the process have

  7. The greenhouse gas intensity and potential biofuel production capacity of maize stover harvest in the US Midwest

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Curtis D. [Department of Geographical Sciences, University of Maryland, College Park MD 20742 USA; Zhang, Xuesong [Joint Global Change Research Institute, Pacific Northwest National Laboratory and University of Maryland, College Park MD 20740 USA; Reddy, Ashwan D. [Department of Geographical Sciences, University of Maryland, College Park MD 20742 USA; Robertson, G. Philip [Great Lakes Bioenergy Research Center, Michigan State University, East Lansing MI 48824 USA; W.K. Kellogg Biological Station, Michigan State University, Hickory Corners MI 49060 USA; Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing MI 48824 USA; Izaurralde, Roberto César [Department of Geographical Sciences, University of Maryland, College Park MD 20742 USA; Texas A& M AgriLife Research & Extension Center, Temple TX 76502 USA

    2017-08-11

    Agricultural residues are important sources of feedstock for a cellulosic biofuels industry that is being developed to reduce greenhouse gas emissions and improve energy independence. While the US Midwest has been recognized as key to providing maize stover for meeting near-term cellulosic biofuel production goals, there is uncertainty that such feedstocks can produce biofuels that meet federal cellulosic standards. Here, we conducted extensive site-level calibration of the Environmental Policy Integrated Climate (EPIC) terrestrial ecosystems model and applied the model at high spatial resolution across the US Midwest to improve estimates of the maximum production potential and greenhouse gas emissions expected from continuous maize residue-derived biofuels. A comparison of methodologies for calculating the soil carbon impacts of residue harvesting demonstrates the large impact of study duration, depth of soil considered, and inclusion of litter carbon in soil carbon change calculations on the estimated greenhouse gas intensity of maize stover-derived biofuels. Using the most representative methodology for assessing long-term residue harvesting impacts, we estimate that only 5.3 billion liters per year (bly) of ethanol, or 8.7% of the near-term US cellulosic biofuel demand, could be met under common no-till farming practices. However, appreciably more feedstock becomes available at modestly higher emissions levels, with potential for 89.0 bly of ethanol production meeting US advanced biofuel standards. Adjustments to management practices, such as adding cover crops to no-till management, will be required to produce sufficient quantities of residue meeting the greenhouse gas emission reduction standard for cellulosic biofuels. Considering the rapid increase in residue availability with modest relaxations in GHG reduction level, it is expected that management practices with modest benefits to soil carbon would allow considerable expansion of potential cellulosic

  8. Study of the acceleration of ammonia generation process from poultry residues aiming at hydrogen production

    International Nuclear Information System (INIS)

    Egute, Nayara dos Santos

    2010-01-01

    The hydrogen, utilized in fuel cells, can be produced from a variety of intermediate chemicals, between them, the ammonia. The ammonia gas as a raw material for the hydrogen production has been used due to its high energetic content, facility of decomposition, high availability, low prices, low storage pressure and its by-products are environmentally correct. One of the sources of ammonia is poultry and egg production systems. In these systems the ammonia is produced from the decomposition of uric acid present in the excreta of birds. The residue from the poultry-rearing farms is the broiler litter and from the egg production system is the excreta without any substrate. The characterization of these residues was performed using the Wavelength-Dispersive X-Ray Fluorescence (WDXRF), Elementary Analysis (CHN), Thermogravimetry and GC/MS - Gas chromatography/ Mass spectrometry. The studied factors which influence the ammonia volatilization were: nitrogen content, raising period, urease enzyme, temperature, pH and moisture content. The experiment results with poultry litter and excreta allow to conclude that the manipulation of the following parameters increased the ammonia emission: pH, nitrogen content, raising period, age of birds and excreta accumulation, urease enzyme and the temperature. The addition of different amounts of sand in the excreta and different volumes of water in the poultry litter inhibited the emission of ammonia. The variation of the quantity of material (broiler litter or excreta) and the volume of the flask used as incubator chamber showed no significant alterations to be chosen as a variable. The excreta was considered more appropriate than poultry litter for the objectives of this work due to the higher ammonia concentrations determined in this material. Due to the large amount of poultry litter and excreta from the production processes, the reuse of poultry residues to obtain ammonia is necessary to improve the quality of the local

  9. Utilization of residue from cassava starch processing for production of fermentable sugar by enzymatic hydrolysis

    Directory of Open Access Journals (Sweden)

    Luciana Reis Fontinelle SOUTO

    2016-01-01

    Full Text Available Abstract The aim of this study was to characterize and perform enzymatic hydrolysis of cassava peeling residue (peel and inner peel, mainly composed of peels and small pieces. Residue was sanitized, dried at 55 °C for 24 hours and ground. The obtained flour showed pH of 4.85; 72.53 g 100 g–1 moisture; 5.18 mL 1M NaOH 100 g–1 acidity; 60.68 g 100 g–1 starch; 1.08 g 100 g–1 reducing sugar; 1.63 g 100g–1 ash; 0.86 g 100 g–1 lipid and 3.97 g 100 g–1 protein. Enzymatic hydrolysis was carried out by means of rotational central composite design, analyzing the effects of concentrations of α-amylase enzyme (10 to 50 U g starch–1, and the amyloglucosidase enzyme (80 to 400 U g starch–1 on variable responses: percent conversion of starch into reducing sugars (RSC and soluble solid content (SS. Highest values of RSC (110% and SS (12 °Brix were observed when using the maximum concentration of amyloglucosidase and throughout the concentration range of α-amylase. Enzymatic hydrolysis of cassava peel is feasible and allows the use of hydrolysate in fermentation processes for the production of various products, such as alcoholic drinks, vinegar, among others.

  10. The water footprint of biofuel produced from forest wood residue via a mixed alcohol gasification process

    International Nuclear Information System (INIS)

    Chiu, Yi-Wen; Wu, May

    2013-01-01

    Forest residue has been proposed as a feasible candidate for cellulosic biofuels. However, the number of studies assessing its water use remains limited. This work aims to analyze the impacts of forest-based biofuel on water resources and quality by using a water footprint approach. A method established here is tailored to the production system, which includes softwood, hardwood, and short-rotation woody crops. The method is then applied to selected areas in the southeastern region of the United States to quantify the county-level water footprint of the biofuel produced via a mixed alcohol gasification process, under several logistic systems, and at various refinery scales. The results indicate that the blue water sourced from surface or groundwater is minimal, at 2.4 liters per liter of biofuel (l/l). The regional-average green water (rainfall) footprint falls between 400 and 443 l/l. The biofuel pathway appears to have a low nitrogen grey water footprint averaging 25 l/l at the regional level, indicating minimal impacts on water quality. Feedstock mix plays a key role in determining the magnitude and the spatial distribution of the water footprint in these regions. Compared with other potential feedstock, forest wood residue shows promise with its low blue and grey water footprint. (letter)

  11. The water footprint of biofuel produced from forest wood residue via a mixed alcohol gasification process

    Science.gov (United States)

    Chiu, Yi-Wen; Wu, May

    2013-09-01

    Forest residue has been proposed as a feasible candidate for cellulosic biofuels. However, the number of studies assessing its water use remains limited. This work aims to analyze the impacts of forest-based biofuel on water resources and quality by using a water footprint approach. A method established here is tailored to the production system, which includes softwood, hardwood, and short-rotation woody crops. The method is then applied to selected areas in the southeastern region of the United States to quantify the county-level water footprint of the biofuel produced via a mixed alcohol gasification process, under several logistic systems, and at various refinery scales. The results indicate that the blue water sourced from surface or groundwater is minimal, at 2.4 liters per liter of biofuel (l/l). The regional-average green water (rainfall) footprint falls between 400 and 443 l/l. The biofuel pathway appears to have a low nitrogen grey water footprint averaging 25 l/l at the regional level, indicating minimal impacts on water quality. Feedstock mix plays a key role in determining the magnitude and the spatial distribution of the water footprint in these regions. Compared with other potential feedstock, forest wood residue shows promise with its low blue and grey water footprint.

  12. Investigation of Performance and Residual Stress Generation of AlSi10Mg Processed by Selective Laser Melting

    Directory of Open Access Journals (Sweden)

    Lianfeng Wang

    2018-01-01

    Full Text Available During the selective laser melting (SLM process, the scanned layers are subjected to rapid thermal cycles. By working on the mechanical properties, residual stress, and microstructure, the high-temperature gradients can have significant effect on the proper functioning and the structural integrity of built parts. This work presents a comprehensive study on the scanning path type and preheating temperature for AlSi10Mg alloy during SLM. According to the results, SLM AlSi10Mg parts fabricated in chessboard scanning strategy have higher mechanical properties or at least comparable to the parts fabricated in uniformity scanning strategy. In the SLM processing, the residual stress in different parts of the specimen varies with temperature gradient, and the residual stress at the edge of the specimen is obviously larger than that at the center. Under the chessboard scanning and preheating temperature 160°C, the residual stress in each direction of the specimens reaches the minimum. Under different forming processes, the morphology of the microstructure is obviously different. With the increase of preheating temperature, the molten pool in the side surface is obviously elongated and highly unevenly distributed. From the coupling relationship between the residual stress and microstructure, it can be found that the microstructure of top surface is affected by residual stresses σx and σy. But the side surface is mainly governed by residual stress σy; moreover, the greater the residual stress, the more obvious the grain tilt. In the XY and XZ surfaces, the scanning strategy has little influence on the tilt angle of the grain. But, the tilt angle and morphology of the microstructure are obviously affected by the preheating temperature. The results show that the residual stresses can effectively change the properties of the materials under the combined influence of scanning strategy and preheating temperature.

  13. Effect of processing on the disappearance of pesticide residues in fresh-cut lettuce: Bioavailability and dietary risk.

    Science.gov (United States)

    Camara, Miguel A; Barba, Alberto; Cermeño, Sandra; Martinez, Gracia; Oliva, Jose

    2017-12-02

    The aim of this research is to establish the processing factors of six pesticides durong the preparation of fresh-cut lettuce and to assess the risk of ingestion of pesticide residues associated with the consumption of the same. A field study was carried out on the dissipation of three insecticides (imidacloprid, tebufenozide, cypermethrin) and three fungicides (metalaxyl, tebuconazole, azoxystrobin) during treatment conditions simulating those used for commercial fresh-cut lettuce. A simultaneous residue analysis method is validated using QuEChERS extraction with acetonitrile and CG-MS and LC-MS/MS analysis. The residues detected after field application never exceed the established Maximum Residue Limits. The processing factors were generally less than 1 (between 0.34 for tebufenozide and 0.53 for imidacloprid), indicating that the process, as a whole, considerably reduces residue levels in processed lettuce compared to fresh lettuce. It is confirmed that cutting, followed by washing and drying, considerably reduces the residues. A matrix effect in the dialyzation of the pesticides is observed and the in vitro study of bioavailability establishes a low percentage of stomach absorption capacity (<15%). The EDI/ADI ratios found in all cases were well below their ADI values, and the dietary exposure assessed (EDI) in fresh-cut lettuce showed no concerns for consumer health.

  14. Lipid accumulation by pelletized culture of Mucor circinelloides on corn stover hydrolysate.

    Science.gov (United States)

    Reis, Cristiano E R; Zhang, Jianguo; Hu, Bo

    2014-09-01

    Microbial oil accumulated by fungal cells is a potential feedstock for biodiesel production, and lignocellulosic materials can serve as the carbon source to support the fungal growth. The dilute acid pretreatment of corn stover can effectively break down its lignin structure, and this process generates a hydrolysate containing mostly xylose at very dilute concentration and numerous by-products that may significantly inhibit the cell growth. This study utilized corn stover hydrolysate as the culture media for the growth of Mucor circinelloides. The results showed that Mucor cells formed pellets during the cell growth, which facilitates the cell harvest from dilute solution. The results also showed that the inhibitory effect of furfural, 5-hydroxymethylfurfural (HMF), and acetic acid could be avoided if their concentration was low. In fact, all these by-products may be assimilated as carbon sources for the fungal growth. The results proved the feasibility to reuse the cultural broth water for acid pretreatment and then use for subsequent cell cultivation. The results will have a direct impact on the overall water usage of the process.

  15. Detoxification and immobilization of chromite ore processing residue in spinel-based glass-ceramic

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Chang-Zhong [Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou 510650 (China); Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region (China); Tang, Yuanyuan [School of Environmental Science and Engineering, South University of Science and Technology of China, Shenzhen 518055 (China); Lee, Po-Heng [Department of Civil & Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong Special Administrative Region (China); Liu, Chengshuai, E-mail: csliu@soil.gd.cn [Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou 510650 (China); State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550009 (China); Shih, Kaimin, E-mail: kshih@hku.hk [Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region (China); Li, Fangbai [Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou 510650 (China)

    2017-01-05

    Graphical abstract: Schematic illustration of detoxification and immobilization of chromite ore processing residue in spinel-based glass-ceramic matrix. All Cr(VI) species is reduced to Cr(III) and most chromium contents are incorporated into spinel structure where the residual chromium are resided in the glass networks. - Highlights: • COPR was detoxified and immobilized in a spinel-based glass-ceramic matrix. • Cr-rich crystalline phase was determined to be MgCr{sub 1.32}Fe{sub 0.19}Al{sub 0.49}O{sub 4} spinel. • The partitioning ratio of Cr into spinel in the glass-ceramic can be up to 77%. • No Cr(VI) was observed after conversion of COPR into a glass-ceramic. • TCLP results demonstrate the superiority of the final product in immobilizing Cr. - Abstract: A promising strategy for the detoxification and immobilization of chromite ore processing residue (COPR) in a spinel-based glass-ceramic matrix is reported in this study. In the search for a more chemically durable matrix for COPR, the most critical crystalline phase for Cr immobilization was found to be a spinel solid solution with a chemical composition of MgCr{sub 1.32}Fe{sub 0.19}Al{sub 0.49}O{sub 4}. Using Rietveld quantitative X-ray diffraction analysis, we identified this final product is with the phases of spinel (3.5 wt.%), diopside (5.2 wt.%), and some amorphous contents (91.2 wt.%). The partitioning ratio of Cr reveals that about 77% of the Cr was incorporated into the more chemically durable spinel phase. The results of Cr K-edge X-ray absorption near-edge spectroscopy show that no Cr(VI) was observed after conversion of COPR into a glass-ceramic, which indicates successful detoxification of Cr(VI) into Cr(III) in the COPR-incorporated glass-ceramic. The leaching performances of Cr{sub 2}O{sub 3} and COPR-incorporated glass-ceramic were compared with a prolonged acid-leaching test, and the results demonstrate the superiority of the COPR-incorporated glass-ceramic matrix in the

  16. Prediction of microstructure, residual stress, and deformation in laser powder bed fusion process

    Science.gov (United States)

    Yang, Y. P.; Jamshidinia, M.; Boulware, P.; Kelly, S. M.

    2017-12-01

    Laser powder bed fusion (L-PBF) process has been investigated significantly to build production parts with a complex shape. Modeling tools, which can be used in a part level, are essential to allow engineers to fine tune the shape design and process parameters for additive manufacturing. This study focuses on developing modeling methods to predict microstructure, hardness, residual stress, and deformation in large L-PBF built parts. A transient sequentially coupled thermal and metallurgical analysis method was developed to predict microstructure and hardness on L-PBF built high-strength, low-alloy steel parts. A moving heat-source model was used in this analysis to accurately predict the temperature history. A kinetics based model which was developed to predict microstructure in the heat-affected zone of a welded joint was extended to predict the microstructure and hardness in an L-PBF build by inputting the predicted temperature history. The tempering effect resulting from the following built layers on the current-layer microstructural phases were modeled, which is the key to predict the final hardness correctly. It was also found that the top layers of a build part have higher hardness because of the lack of the tempering effect. A sequentially coupled thermal and mechanical analysis method was developed to predict residual stress and deformation for an L-PBF build part. It was found that a line-heating model is not suitable for analyzing a large L-PBF built part. The layer heating method is a potential method for analyzing a large L-PBF built part. The experiment was conducted to validate the model predictions.

  17. Acetic acid removal from corn stover hydrolysate using ethyl acetate and the impact on Saccharomyces cerevisiae bioethanol fermentation.

    Science.gov (United States)

    Aghazadeh, Mahdieh; Ladisch, Michael R; Engelberth, Abigail S

    2016-07-08

    Acetic acid is introduced into cellulose conversion processes as a consequence of composition of lignocellulose feedstocks, causing significant inhibition of adapted, genetically modified and wild-type S. cerevisiae in bioethanol fermentation. While adaptation or modification of yeast may reduce inhibition, the most effective approach is to remove the acetic acid prior to fermentation. This work addresses liquid-liquid extraction of acetic acid from biomass hydrolysate through a pathway that mitigates acetic acid inhibition while avoiding the negative effects of the extractant, which itself may exhibit inhibition. Candidate solvents were selected using simulation results from Aspen Plus™, based on their ability to extract acetic acid which was confirmed by experimentation. All solvents showed varying degrees of toxicity toward yeast, but the relative volatility of ethyl acetate enabled its use as simple vacuum evaporation could reduce small concentrations of aqueous ethyl acetate to minimally inhibitory levels. The toxicity threshold of ethyl acetate, in the presence of acetic acid, was found to be 10 g L(-1) . The fermentation was enhanced by extracting 90% of the acetic acid using ethyl acetate, followed by vacuum evaporation to remove 88% removal of residual ethyl acetate along with 10% of the broth. NRRL Y-1546 yeast was used to demonstrate a 13% increase in concentration, 14% in ethanol specific production rate, and 11% ethanol yield. This study demonstrated that extraction of acetic acid with ethyl acetate followed by evaporative removal of ethyl acetate from the raffinate phase has potential to significantly enhance ethanol fermentation in a corn stover bioethanol facility. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:929-937, 2016. © 2016 American Institute of Chemical Engineers.

  18. Production of hydrolysate from processed Nile tilapia (Oreochromis niloticus residues and assessment of its antioxidant activity

    Directory of Open Access Journals (Sweden)

    Daniela Miotto BERNARDI

    2016-01-01

    Full Text Available Abstract The objective of this work was to produce protein hydrolysates from by-products of the Nile tilapia fileting process, and to assess the effects of different hydrolysis times on the antioxidant activity of the hydrolysed animal-based protein, in free form and incorporated into a food matrix. Gutted tilapia heads and carcasses were hydrolysed by Alcalase® for different hydrolysis times producing six hydrolysates. The protein content, degree of hydrolysis, reverse-phase high-performance liquid chromatography, and antioxidant activity by the ORAC, FRAP and TEAC methods were analysed. Three mini-hamburger formulations were produced and the lipidic oxidation of mini-hamburger was determined by TBARS. The protein contained in the residue was completely recovered in the process. The hydrolysates varied in their degree of hydrolysis, but presented similar levels of antioxidant activity. In the mini-hamburgers the hydrolysate was capable of delaying oxidation after 7 days of storage. Hydrolysis of tilapia processing by-products produced peptides may be used in the formulation of functional foods.

  19. Biotransformation of some industries residuals and evaluation of their humification process

    International Nuclear Information System (INIS)

    Bravo Isabel; Giraldo E; Garces P

    2001-01-01

    At the Cauca Department, manures are using obtained by means of compost of agricultural and cattle waste, with base in a Central American formula (Bocashi). Fifteen days after their preparation, these manures are applied to different crops. It is sought to replace some components to give it use to agro industrial waste that have not been found utility, among them residual fine dust of bagasse cane (marrow) generated during paper production; vinasse and husk of coffee and hen-dung that is expensive and of difficult access for all farmers. The humification process is also evaluated in 60 days period. Three bio-organic fertilizers were prepared by means of compost of materials: coffee husk until 26.7%. Fine dust until 11% and vinasse until 34% the following parameters were evaluated: humification degree by determination of organic matter (MO), humic acid, fulvic acid, humification relationships, cation exchange capacity (CIC) and C/N relationship. Physicochemical parameters like: temperature, pH, and content of nutrients. The presence of fine dust in manure improved the physicochemical properties achieving a better microbial development that is translated in a better humification process and bigger content of nutrients. The results demonstrate that at 15 days it is still incipient the maturation process, and that in the evaluated period it has not finished the humification; that hen-dung can be replaced by cattle manure whenever it is in fine e dust presence and that coffee husk is useful for obtaining bio-organic fertilizers

  20. Control of the residual aluminum in drinking water by optimization of the coagulation process

    International Nuclear Information System (INIS)

    Jaouadi, Mouna; Amdouni, Noureddine; Chaouchi, Mohamed

    2009-01-01

    Coagulation-Flocculation is an unavoidable stage in water treatment. It permits to reduce the color and the turbidity, normally caused by the organic and inorganic contaminants to acceptable levels for drinking water or for wastewater. The used coagulants can be organic or inorganic nature. The main goal of this work is to make the follow-up of water quality parameters and the optimization of the clarification stages in the drinking waters treatment station, by determination of the break point in the stage of the prechloration and optimization of the coagulant (aluminum sulphate) proportion. The determination of the anions concentration by means of the ionic chromatography before and after coagulation-flocculation shows that the stability and the solubility of the aluminum species are strongly affected by the presence of these anions. Consequently, the content of the anions affects the process of coagulation and must be taken into account in the optimization of this process. We present in this communication, the results of the pH, concentration of the coagulant, time of coagulation effect on the coagulation process .These factors show optimum values. The research of residual aluminum in the two water studied during this work shows that the aluminum content is lower than 200 g/L at the pH optimum.

  1. Development of an integrated process to produce d-mannose and bioethanol from coffee residue waste.

    Science.gov (United States)

    Nguyen, Quynh Anh; Cho, Eunjin; Trinh, Ly Thi Phi; Jeong, Ji-Su; Bae, Hyeun-Jong

    2017-11-01

    A novel, integrated process for economical high-yield production of d-mannose and ethanol from coffee residue waste (CRW), which is abundant and widely available, was reported. The process involves pretreatment, enzymatic hydrolysis, fermentation, color removal, and pervaporation, which can be performed using environmentally friendly technologies. The CRW was pretreated with ethanol at high temperature and then hydrolyzed with enzymes produced in-house to yield sugars. Key points of the process are: manipulations of the fermentation step that allowing bioethanol-producing yeasts to use almost glucose and galactose to produce ethanol, while retaining large amounts of d-mannose in the fermented broth; removal of colored compounds and other components from the fermented broth; and separation of ethanol and d-mannose through pervaporation. Under optimized conditions, approximately 15.7g dry weight (DW) of d-mannose (approximately 46% of the mannose) and approximately 11.3g DW of ethanol from 150g DW of ethanol-pretreated CRW, were recovered. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Comparison of the Effects of Thermal Pretreatment, Steam Explosion and Ultrasonic Disintegration on Digestibility of Corn Stover

    Directory of Open Access Journals (Sweden)

    Andras Dallos

    2016-06-01

    Full Text Available The energy demand of the corn-based bioethanol production could be reduced using the agricultural byproducts as bioenergy feedstock for biogas digesters. The release of lignocellulosic material and therefore the acceleration of degradation processes can be achieved using thermal and mechanical pretreatments, which assist to hydrolyze the cell walls and speed the solubilization of biopolymers in biogas feedstock. This study is focused on liquid hot water, steam explosion and ultrasonic pretreatments of corn stover. The scientific contribution of this paper is a comprehensive comparison of the performance of the pretreatments by fast analytical, biochemical, anaerobic digestibility and biomethane potential tests, extended by energy consumptions and energy balance calculations.The effectiveness of pretreatments was evaluated by means of soluble chemical oxygen demand, biochemical oxygen demand and by the biogas and methane productivities. The results have shown that the thermal pretreatment, steam explosion and ultrasonic irradiation of biogas feedstock disintegrated the lignocellulosic structure, increased and accelerated the methane production and increased the cumulative biogas and methane productivity of corn stover in reference to the control during mesophilic anaerobic digestion.The energy balance demonstrated that there is an economical basis of the application of the liquid hot-compressed water pretreatments in a biogas plant. However, the steam explosion and ultrasonication are energetically not profitable for corn stover pretreatment.

  3. Effect of poultry litter biochar on Saccharomyces cerevisiae growth and ethanol production from steam-exploded poplar and corn stover

    Science.gov (United States)

    Diallo, Oumou

    The use of ethanol produced from lignocellulosic biomass for transportation fuel offers solutions in reducing environmental emission and the use of non-renewable fuels. However, lignocellulosic ethanol production is still hampered by economic and technical obstacles. For instance, the inhibitory effect of toxic compounds produced during biomass pretreatment was reported to inhibit the fermenting microorganisms, hence there was a decrease in ethanol yield and productivity. Thus, there is a need to improve the bioconversion of lignocellulosic biomass to ethanol in order to promote its commercialization. The research reported here investigated the use of poultry litter biochar to improve the ethanol production from steam-exploded poplar and corn stover. The effect of poultry litter biochar was first studied on Saccharomyces cerevisiae ATCC 204508/S288C growth, and second on the enzyme hydrolysis and fermentation of two steam-exploded biomasses: (poplar and corn stover). The third part of the study investigated optimal process parameters (biochar loading, biomass loading, and enzyme loading) on the reducing sugars production, and ethanol yield from steam-exploded corn stover. In this study, it has been shown that poultry litter biochar improved the S. cerevisiae growth and ethanol productivity; therefore poultry litter biochar could potentially be used to improve the ethanol production from steam-exploded lignocellulosic biomass.

  4. Corn stover saccharification with concentrated sulfuric acid: effects of saccharification conditions on sugar recovery and by-product generation.

    Science.gov (United States)

    Liu, Ze-Shen; Wu, Xiao-Lei; Kida, Kenji; Tang, Yue-Qin

    2012-09-01

    Although concentrated sulfuric acid saccharification is not a novel method for breaking down lignocellulosic biomass, the process by which saccharification affects biomass decomposition, sugar recovery, and by-product generation is not well studied. The present study employed Taguchi experimental design to study the effects of seven parameters on corn stover concentrated sulfuric acid saccharification. The concentration of sulfuric acid and the temperature of solubilization significantly affect corn stover decomposition. They also have significant effects on glucose and xylose recoveries. Low generation of furfural and 5-hydroxymethyl-2-furfural (5HMF) was noted and organic acids were the main by-products detected in the hydrolysate. Temperature also significantly affected the generation of levulinic acid and formic acid; however, acetic acid generation was not significantly influenced by all seven parameters. The ratio of acid to feedstock significantly affected glucose recovery, but not total sugar recovery. The corn stover hydrolysate was well fermented by both glucose- and xylose-fermenting yeast strains. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Upgrading of automobile shredder residue via innovative granulation process 'ReGran'.

    Science.gov (United States)

    Holthaus, Philip; Kappes, Moritz; Krumm, Wolfgang

    2017-01-01

    Stricter regulatory requirements concerning end-of-life vehicles and rising disposal costs necessitate new ways for automobile shredder residue utilisation. The shredder granulate and fibres, produced by the VW-SICON-Process, have a high energy content of more than 20 MJ kg -1 , which makes energy recovery an interesting possibility. Shredder fibres have a low bulk density of 60 kg m -3 , which prevents efficient storing and utilisation as a refuse-derived fuel. By mixing fibres with plastic-rich shredder granulate and heating the mixture, defined granules can be produced. With this 'ReGran' process, the bulk density can be enhanced by a factor of seven by embedding shredder fibres in the partially melted plastic mass. A minimum of 26-33 wt% granulate is necessary to create enough melted plastic. The process temperature should be between 240 °C and 250 °C to assure fast melting while preventing extensive outgassing. A rotational frequency of the mixing tool of 1000 r min -1 during heating and mixing ensures a homogenous composition of the granules. During cooling, lower rotational frequencies generate bigger granules with particles sizes of up to 60 mm at 300 r min -1 . To keep outgassing to a minimum, it is suggested to melt shredder granulate first and then add shredder fibres. Adding coal, wood or tyre fluff as a third component reduces chlorine levels to less than 1 wt%. The best results can be achieved with tyre fluff. In combination with the VW-SICON-Process, ReGran produces a solid recovered fuel or 'design fuel' tailored to the requirements of specific thermal processes.

  6. Sweet sorghum bagasse and corn stover serving as substrates for producing sophorolipids

    Energy Technology Data Exchange (ETDEWEB)

    Samad, Abdul; Zhang, Ji; Chen, Da; Chen, Xiaowen; Tucker, Melvin; Liang, Yanna

    2016-12-28

    To make the process of producing sophorolipids by Candida bombicola truly sustainable, we investigated production of these biosurfactants on biomass hydrolysates. This study revealed: (1) yield of sophorolipds on bagasse hydrolysate decreased from 0.56 to 0.54 and to 0.37 g/g carbon source when yellow grease was dosed at 10, 40 and 60 g/L, respectively. In the same order, concentration of sophorolipids was 35.9, 41.9, and 39.3 g/L; (2) under similar conditions, sophorolipid yield was 0.12, 0.05 and 0.04 g/g carbon source when corn stover hydrolysate was mixed with soybean oil at 10, 20 and 40 g/L. Sophorolipid concentration was 11.6, 4.9, and 3.9 g/L for the three oil doses from low to high; and (3) when corn stover hydrolysate and yellow grease served as the substrates for cultivating the yeast in a fermentor, sophorolipid concentration reached 52.1 g/L. Upon further optimization, sophorolipids production from ligocellulose will be indeed sustainable.

  7. Comparison of different ionic liquids pretreatment for corn stover enzymatic saccharification.

    Science.gov (United States)

    Mood, Sohrab Haghighi; Golfeshan, Amir Hossein; Tabatabaei, Meisam; Abbasalizadeh, Saeed; Ardjmand, Mehdi; Jouzani, Gholamreza Salehi

    2014-01-01

    Recently, application of ionic liquids (ILs) has received much attention due to their special solvency properties as a promising method of pretreatment for lignocellulosic biomass. Easy recovery of ionic liquids, chemical stability, temperature stability, nonflammability, low vapor pressure, and wide liquidus range are among those unique properties. These solvents are also known as green solvents due to their low vapor pressure. The present study was set to compare the effect of five different ILs, namely, 1-ethyl-3-methylimidazolium acetate ([EMIM][Ac]), 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]), 1-ethyl-3-methyl imidazolium diethyl phosphate ([EMIM][DEP]), 1-allyl-3-methylimidazolium chloride ([AMIM][Cl]), and 1-ethyl-3-methylimidazolium-hydrogen sulfate ([EMIM][HSO₄]), on corn stover in a bioethanol production process. The performance of ILs was evaluated based on the change observed in chemical structure, crystallinity index, cellulose digestibility, and glucose release. Overall, [EMIM][Ac]-pretreated corn stover led to significantly higher saccharification, with cellulose digestibility reaching 69% after 72 hr, whereas digestibility of untreated barley straw was measured at only 21%.

  8. Development of Corn Stover Biofuel: Impacts on Corn and Soybean Markets and Land Rotation

    OpenAIRE

    Taheripour, Farzad; Tyner, Wallace E.; Fiegel, Julie

    2013-01-01

    This paper first develops a partial equilibrium (PE) model to examine impacts of converting corn stover to biofuel on markets for corn and soybeans at the national market level. The PE model links gasoline, corn ethanol, dried distiller grains, corn, soybeans, and soybean meal markets in the presence and absence of a viable market for corn stover. The model also includes a technology which converts corn stover to bio-gasoline (a drop-in biofuel). The model evaluates profitability of the ethan...

  9. Effect of processing conditions and methods on residual stress in CeO2 buffer layers and YBCO superconducting films

    International Nuclear Information System (INIS)

    Xiong Jie; Qin Wenfeng; Cui Xumei; Tao Bowan; Tang Jinlong; Li Yanrong

    2006-01-01

    CeO 2 layers have been fabricated by pulsed laser deposition (PLD) technique on (1 1 0 2) sapphire substrate. Microstructure of CeO 2 layers is characterized by X-ray diffraction as functions of substrate temperature. The effects of the substrate temperature on the residual stress have been studied. The results show that residual stress in CeO 2 film decreased with increasing substrate temperature, not the same development tendency as that of thermal stress. This means that the thermal stress is only a fraction of the residual stress. Moreover, YBCO superconducting films were prepared by direct current (DC) sputtering and pulsed laser deposition (PLD) technique. The residual stress and thermal stress of both YBCO films were measured. PLD processing apparently generated higher intrinsic compressive stresses in comparison to DC sputtering

  10. On the Influence of Laser Cladding and Post-processing Strategies on Residual Stresses in Steel Specimens

    Science.gov (United States)

    Köhler, H.; Rajput, R.; Khazan, P.; Kornmeier, J. Rebelo

    Thermal cycles during laser cladding can alter mechanical properties of the original part significantly. In case of cyclically loaded parts residual stresses are suspected to be a property strongly determining fatigue life. Therefore, in this paper the influence of processing and post-processing strategies on resulting residual stresses are determined by neutron-diffraction. A low-alloy as well as a high-alloy steel have been considered within this study, both cladded with the Co-based superalloy Stellite 21. Processing speed and post-treatment by laser annealing and by deep rolling strategies have been tested. Residual stresses in low-alloyed steel show high sensitivity on applied treatment strategies. In the present study only deep rolling induced compressive residual stress close to the part surface. In high-alloy steel compressive stress in this area resulted directly after laser cladding, where its magnitude depends on processing speed. A compressive residual stress statewhich is suspected to be beneficial for fatigue strength could be achieved at the two representative steels.

  11. Pretreatment of Corn Stover by Low Moisture Anhydrous Ammonia (LMAA) in a Pilot-Scale Reactor and Bioconversion to Fuel Ethanol and Industrial Chemicals.

    Science.gov (United States)

    Nghiem, Nhuan P; Senske, Gerard E; Kim, Tae Hyun

    2016-04-01

    Corn stover (CS) adjusted to 50, 66, and 70 % moisture was pretreated by the low moisture anhydrous ammonia (LMAA) process in a pilot-scale ammoniation reactor. After ammoniation, the 70 % moisture CS was treated at 90 and 100 °C whereas the others were treated at 90 °C only. The 70 % moisture pretreated CS then was subjected to a storage study under non-sterile conditions for 3 months. It was found that storage time did not have significant effects on the compositions of the pretreated materials and their hydrolysis by commercial enzymes. The 70 % moisture CS treated at 90 °C was used for preparation of a mix sugar hydrolysate (MSH) using combination of cellulase and xylanase. The MSH was used to prepare a corn mash at 9.5 wt% solid then subjected to ethanol fermentation by Escherichia coli KO11. The 66 % moisture CS treated at 90 °C was hydrolyzed with xylanase to make a xylose-rich hydrolysate (XRH), which was subsequently used for butyric acid fermentation by Clostridium tyrobutyricum. The resultant cellulose-enriched residue was hydrolyzed with cellulase to make a glucose-rich hydrolysate (GRH), which was subsequently used for succinic acid fermentation by E. coli AFP184.

  12. A bio-based ‘green’ process for catalytic adipic acid production from lignocellulosic biomass using cellulose and hemicellulose derived γ-valerolactone

    International Nuclear Information System (INIS)

    Han, Jeehoon

    2016-01-01

    Highlights: • A bio-based ‘green’ process for catalytic conversion of corn stover to adipic acid (ADA) is studied. • New separations for effective recovery of biomass derivatives are developed. • Separations are integrated with cellulose/hemicellulose-to-ADA conversions. • Proposed process can compete economically with the current petro-based process. - Abstract: A bio-based ‘green’ process is presented for the catalytic conversion of corn stover to adipic acid (ADA) based on experimental studies. ADA is used for biobased nylon 6.6 manufacturing from lignocellulosics as carbon and energy source. In this process, the cellulose and hemicellulose fractions are catalytically converted to γ-valerolactone (GVL), using cellulose and hemicellulose-derived GVL as a solvent, and subsequently upgrading to ADA. Experimental studies showed maximal carbon yields (biomass-to-GVL: 41% and GVL-to-ADA: 46%) at low concentrations (below 16 wt% solids) using large volumes of GVL solvents while requiring efficient interstage separations and product recovery. This work presents an integrated process, including catalytic conversion and separation subsystems for GVL and ADA production and recovery, and designs a heat exchanger network to satisfy the total energy requirements of the integrated process via combustion of biomass residues (lignin and humins). Finally, an economic analysis shows that 2000 metric tonnes (Mt) per day of corn stover feedstock processing results in a minimum selling price of $633 per Mt if using the best possible parameters.

  13. Contribution of Sample Processing to Variability and Accuracy of the Results of Pesticide Residue Analysis in Plant Commodities.

    Science.gov (United States)

    Ambrus, Árpád; Buczkó, Judit; Hamow, Kamirán Á; Juhász, Viktor; Solymosné Majzik, Etelka; Szemánné Dobrik, Henriett; Szitás, Róbert

    2016-08-10

    Significant reduction of concentration of some pesticide residues and substantial increase of the uncertainty of the results derived from the homogenization of sample materials have been reported in scientific papers long ago. Nevertheless, performance of methods is frequently evaluated on the basis of only recovery tests, which exclude sample processing. We studied the effect of sample processing on accuracy and uncertainty of the measured residue values with lettuce, tomato, and maize grain samples applying mixtures of selected pesticides. The results indicate that the method is simple and robust and applicable in any pesticide residue laboratory. The analytes remaining in the final extract are influenced by their physical-chemical properties, the nature of the sample material, the temperature of comminution of sample, and the mass of test portion extracted. Consequently, validation protocols should include testing the effect of sample processing, and the performance of the complete method should be regularly checked within internal quality control.

  14. Pretreatment on corn stover with low concentration of formic acid.

    Science.gov (United States)

    Xu, Jian; Thomsen, Mette Hedegaard; Thomsen, Anne Belinda

    2009-08-01

    Bioethanol derived from lignocellulosic biomass has the potential to replace gasoline. Cellulose is naturally recalcitrant to enzymatic attack, and it also surrounded by the matrix of xylan and lignin, which enhances the recalcitrance. Therefore, lignocellulosic materials must be pretreated to make the cellulose easily degraded into sugars and further fermented to ethanol. In this work, hydrothermal pretreatment on corn stover at 195 degrees for 15 min with and without lower concentration of formic acid was compared in terms of sugar recoveries and ethanol fermentation. For pretreatment with formic acid, the overall glucan recovery was 89% and pretreatment without formic acid yielded the recovery of 94%. Compared with glucan, xylan was more sensitive to the pretreatment condition. The lowest xylan recovery of 55% was obtained after pretreatment with formic acid and the highest of 75% found following pretreatment without formic acid. Toxicity tests of liquor parts showed that there were no inhibitions found for both pretreatment conditions. After simultaneous saccharification and fermentation (SSF) of the pretreated corn stover with Baker's yeast, the highest ethanol yield of 76.5% of the theoretical was observed from corn stover pretreated at 195 degrees for 15 min with formic acid.

  15. Composite Cure Process Modeling and Simulations using COMPRO(Registered Trademark) and Validation of Residual Strains using Fiber Optics Sensors

    Science.gov (United States)

    Sreekantamurthy, Thammaiah; Hudson, Tyler B.; Hou, Tan-Hung; Grimsley, Brian W.

    2016-01-01

    Composite cure process induced residual strains and warping deformations in composite components present significant challenges in the manufacturing of advanced composite structure. As a part of the Manufacturing Process and Simulation initiative of the NASA Advanced Composite Project (ACP), research is being conducted on the composite cure process by developing an understanding of the fundamental mechanisms by which the process induced factors influence the residual responses. In this regard, analytical studies have been conducted on the cure process modeling of composite structural parts with varied physical, thermal, and resin flow process characteristics. The cure process simulation results were analyzed to interpret the cure response predictions based on the underlying physics incorporated into the modeling tool. In the cure-kinetic analysis, the model predictions on the degree of cure, resin viscosity and modulus were interpreted with reference to the temperature distribution in the composite panel part and tool setup during autoclave or hot-press curing cycles. In the fiber-bed compaction simulation, the pore pressure and resin flow velocity in the porous media models, and the compaction strain responses under applied pressure were studied to interpret the fiber volume fraction distribution predictions. In the structural simulation, the effect of temperature on the resin and ply modulus, and thermal coefficient changes during curing on predicted mechanical strains and chemical cure shrinkage strains were studied to understand the residual strains and stress response predictions. In addition to computational analysis, experimental studies were conducted to measure strains during the curing of laminated panels by means of optical fiber Bragg grating sensors (FBGs) embedded in the resin impregnated panels. The residual strain measurements from laboratory tests were then compared with the analytical model predictions. The paper describes the cure process

  16. Determination of neomycin residues in pasteurized milks produced in some dairy processing establishments in East-Azarbaijan Province, Iran

    Directory of Open Access Journals (Sweden)

    M.H Movassagh

    2014-11-01

    Full Text Available Antibiotic residues in milk have a potential hazard for the consumer and may cause allergic reactions, interference in the intestinal flora that result in development of resistant populations of bacteria, thereby rendering antibiotic treatment ineffective. The aim of this study was to determine neomycin residues in pasteurized milk in East-Azarbaijan province. For this, a total of 200 samples of pasteurized milk produced by five dairy processing establishments of East Azarbaijan province was randomly collected. The samples were obtained over the spring and autumn (100 samples for each season of 2010. First, antibiotic residues were determined by Copan milk test. Afterwards, the competitive ELISA assay was used for the determination of neomycin concentration in positive samples. Of all samples, neomycin residues were observed in 9 and 13 samples and the mean neomycin residues amount were 43.20 ± 8.10 and 26.63±2.08 µg/L in spring and autumn, respectively. According to the limit of neomycin (1500 µg/l in cow raw milk in Iran, despite all the remaining drugs in pasteurized milk, in any of the samples exceeded level of neomycin was not observed.Based on the results, continuousmonitoringofantibiotic residues inmilk samples is recommended.

  17. High-titer lactic acid production from NaOH-pretreated corn stover by Bacillus coagulans LA204 using fed-batch simultaneous saccharification and fermentation under non-sterile condition.

    Science.gov (United States)

    Hu, Jinlong; Zhang, Zhenting; Lin, Yanxu; Zhao, Shumiao; Mei, Yuxia; Liang, Yunxiang; Peng, Nan

    2015-04-01

    Lactic acid (LA) is an important chemical with various industrial applications. Non-food feedstock is commercially attractive for use in LA production; however, efficient LA fermentation from lignocellulosic biomass resulting in both high yield and titer faces technical obstacles. In this study, the thermophilic bacterium Bacillus coagulans LA204 demonstrated considerable ability to ferment glucose, xylose, and cellobiose to LA. Importantly, LA204 produces LA from several NaOH-pretreated agro stovers, with remarkably high yields through simultaneous saccharification and fermentation (SSF). A fed-batch SSF process conducted at 50°C and pH 6.0, using a cellulase concentration of 30 FPU (filter paper unit)/g stover and 10 g/L yeast extract in a 5-L bioreactor, was developed to produce LA from 14.4% (w/w) NaOH-pretreated non-sterile corn stover. LA titer, yield, and average productivity reached 97.59 g/L, 0.68 g/g stover, and 1.63 g/L/h, respectively. This study presents a feasible process for lignocellulosic LA production from abundant agro stovers. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Effect of household and industrial processing on the levels of pesticide residues and degradation products in melons.

    Science.gov (United States)

    Bonnechère, A; Hanot, V; Bragard, C; Bedoret, T; van Loco, J

    2012-01-01

    Two varieties of melons (Cucumis melo) were treated with two fungicides (carbendazim and maneb) and four insecticides (acetamiprid, cyromazin, imazalil and thiamethoxam) to quantify the effect of household processing on the pesticide residues. To ensure sufficiently high levels of residues in flesh and peel, the most concentrated formulations were applied observing good agricultural practice. The peeling step decreased the concentration of pesticide residues for maneb, imazalil and acetamiprid by more than 90%. Cyromazin, carbendazim and thiamethoxam were reduced by approximately 50%. The reduction of the pesticides could not be fully explained by the systemic character of the pesticides. However, the agricultural practices (time of application), solubility and mode of action (systemic versus contact pesticide) of the pesticides could be used to explain the difference in processing factors for the studied pesticides. Degradation products (melamine and ethylenethiourea) were also investigated in this study, but were not detected.

  19. Application of the Rietveld method to assess chromium(VI) speciation in chromite ore processing residue.

    Science.gov (United States)

    Chrysochoou, Maria; Dermatas, Dimitris

    2007-03-15

    The Rietveld method allows the quantification of crystalline phases and amorphous material identified by X-ray powder diffraction (XRPD) and other diffraction methods. The method assists in determining the speciation of contaminants in solid matrices both qualitatively and quantitatively in a statistically defensible approach, as it does not focus on a microscale. Rietveld was applied to chromite ore processing residue (COPR), a cementitious waste containing hexavalent chromium. Calcium aluminum chromium oxide hydrates (CACs) were the crystalline phases identified by XRPD that bind Cr(6+) in COPR according to their chemical formula. Rietveld quantification, combined with mass balances on Cr(6+), showed that CACs may bind Cr(6+) in variable percentages, ranging from 25% to 85%. Analysis of duplicate samples showed that material variability is the predominant factor of uncertainty in evaluating the role of CACs in Cr(6+) speciation, provided that a consistent quantification strategy is pursued. The choice of strategy was performed on the basis of the pertinent literature, preliminary analyses of the equipment and the software settings, and mass balances. The correlation between the average CAC-bound Cr(6+) concentration and the total Cr(6+) for five samples (R(2)=0.94), extracted from different zones and soil borings, suggests that CACs are a primary sink for Cr(6+) in COPR.

  20. Role of quantitative mineralogical analysis in the investigation of sites contaminated by chromite ore processing residue.

    Science.gov (United States)

    Hillier, S; Roe, M J; Geelhoed, J S; Fraser, A R; Farmer, J G; Paterson, E

    2003-06-01

    A range of techniques, normally associated with mineralogical studies of soils and sediments, has been used to characterise the solid materials found on sites contaminated with chromite ore processing residue (COPR). The results show that a wide range of minerals are present, many of which are found extensively in high-temperature synthetic systems such as cements and clinkers and their low temperature hydration products. Thus, the minerals in COPR can be divided into three main categories: unreacted feedstock ore (chromite); high temperature phases produced during chromium extraction (brownmillerite, periclase and larnite); and finally, minerals formed under ambient weathering conditions on the disposal sites (brucite, calcite, aragonite, ettringite, hydrocalumite, hydrogarnet). Apart from chromite, chromium occurs in brownmillerite, ettringite, hydrocalumite and hydrogarnet. Detailed study of the chemistry and stoichiometry of chromium-bearing phases in conjunction with phase abundance provides a quantitative description of the solid state speciation of Cr(III) and Cr(VI) in and amongst these minerals and in the COPR as a whole. Of the total chromium present in the samples most, approximately 60-70% is present as Cr(III) in chromite, whilst brownmillerite also represents a significant reservoir of Cr(III) which is approximately 15% of the total. The remaining chromium, between 20 and 25%, is present as Cr(VI) and resides mainly in hydrogarnet, and to a slightly lesser extent in hydrocalumite. In the latter, it is present principally in an exchangeable anionic form. Chromium (VI) is also present in ettringite, but quantitatively ettringite is a much less important reservoir of Cr(VI), accounting for approximately 3% of total chromium in one sample, but less than 1% in the other two. This description provides insight into the processes likely to control the retention and release of Cr(VI) from COPR-contaminated sites. Such information is of particular value in

  1. Reconstitution of dewatered food processing residuals with manure to increase energy production from anaerobic digestion

    International Nuclear Information System (INIS)

    Wall, David M.; Wu-Haan, Wei; Safferman, Steven I.

    2012-01-01

    Solid residuals generated from dewatering food processing wastewater contain organic carbon that can potentially be reclaimed for energy through anaerobic digestion. This results in the diversion of waste from a landfill and uses it for a beneficial purpose. Dewatering the waste concentrates the carbon, reducing transportation costs to a farm digester where it can be blended with manure to increase biogas yield. Polymers are often used in the dewatering of the food waste but little is known regarding their impact on biogas production. Four 2 dm 3 working volume, semi-continuous reactors, were used at a mesophilic temperature and a solids retention time (SRT) of 15 days. Reactors were fed daily with a blended feedstock containing a food processing sludge waste (FPSW)/manure ratio of 2.2:1 (by weight) as this produced the optimized carbon to nitrogen ratio. Results demonstrated that reconstitution of dewatered FPSW with dairy manure produced approximately 2 times more methane than animal manure alone for the same volume. However, only approximately 30% of volatile solids (VS) were consumed indicating energy potential still remained. Further, the efficiency of the conversion of VS to methane for the blended FPSW/manure was substantially less than for manure only. However, the overall result is an increase in energy production for a given tank volume, which can decrease life cycle costs. Because all FPSW is unique and the determination of dewatering additives is customized based on laboratory testing and field adjustment, generalizations are difficult and specific testing is required. -- Highlights: ► Energy production in anaerobic digestion can increase by co-blending food waste. ► Energy for transporting food waste to blend with manure is less when dewatered. ► Dewatered food waste in manure produced twice as much methane than manure. ► Efficiency of carbon to methane was low because of ammonium bicarbonate production. ► Carbon destruction was 30%, more

  2. Optimization of the protein concentration process from residual peanut oil-cake

    Directory of Open Access Journals (Sweden)

    Gayol, M. F.

    2013-12-01

    Full Text Available The objective of this study was to find the best process conditions for preparing protein concentrate from residual peanut oil-cake (POC. The study was carried out on POC from industrial peanut oil extraction. Different protein extraction and precipitation conditions were used: water/ flour ratio (10:1, 20:1 and 30:1, pH (8, 9 and 10, NaCl concentration (0 and 0.5 M, extraction time (30, 60 and 120 min, temperature (25, 40 and 60 °C, extraction stages (1, 2 and 3, and precipitation pH (4, 4.5 and 5. The extraction and precipitation conditions which showed the highest protein yield were 10:1 water/flour ratio, extraction at pH 9, no NaCl, 2 extraction stages of 30 min at 40 °C and precipitation at pH 4.5. Under these conditions, the peanut protein concentrate (PC contained 86.22% protein, while the initial POC had 38.04% . POC is an alternative source of protein that can be used for human consumption or animal nutrition. Therefore, it adds value to an industry residue.El objetivo de este trabajo fue encontrar las mejores condiciones para obtener un concentrado de proteínas a partir de la torta residual de maní (POC. El estudio se llevó a cabo en POC provenientes de la extracción industrial de aceite de maní. Se utilizaron distintas condiciones para la extracción y precipitación de proteínas: relación agua / harina (10:1, 20:1 y 30:1, pH de extracción (8, 9 y 10, concentración de NaCl (0 y 0,5 M, tiempo de extracción (30, 60 y 120 min, temperatura (25, 40 y 60 °C, número de etapas de extracción (1, 2 y 3, y el pH de precipitación (4, 4,5 y 5. Las condiciones de extracción y de precipitación que mostraron mayor rendimiento de proteína fueron: relación de 10:1 en agua / harina, pH de extracción de 9, en ausencia de NaCl, 2 etapas de extracción de 30 min cada una a 40 °C y el pH de precipitación de 4,5. En estas condiciones, el concentrado de proteína de maní (PC fue de 86,22%, mientras que el porcentaje de proteínas de

  3. Comparison between Neutron Diffraction measurements and numerical simulation of residual stresses of a Wire-Drawing process

    Directory of Open Access Journals (Sweden)

    Tomaz Fantin de Souza

    2013-04-01

    Full Text Available In this work, a drawing processed was simulated to calculate forces and the resulting residual stresses in the material. The calculated residual stresses were compared with experimentally measured residual stresses by the Neutron Diffraction Method. The modeled process was the Wire Drawing. The necessary parameters to model the process were taken from an industrial currently used process. Rods of an AISI 1045 steel with nominal diameters of 21.46 mm were reduced to 20.25 mm by drawing with an drawing angle of 15°. Compression tests were used to determinate flow curves of the real material an used in the simulation models. The possibility to estimate drawing forces by numerical simulation was evaluated by comparing simulated results with values from empirical equations given by the literature. The results have shown a sufficient accuracy for the calculation of forces, but the comparison of residual stresses has shown differences to the experimentally determined ones that can be minimized by the consideration of high strain rates in the compression tests, anisotropy of the material and kinematic hardening.

  4. Survey of pesticide residues in table grapes: Determination of processing factors, intake and risk assessment

    DEFF Research Database (Denmark)

    Poulsen, Mette Erecius; Hansen, H.K.; Sloth, Jens Jørgen

    2007-01-01

    The differences in residue pattern between Italy and South Africa, the main exporters of table grapes to the Danish market, were investigated. The results showed no major differences with respect to the number of samples with residues, with residues being found in 54-78% of the samples. Exceedances......, no significant effect was found for organophosphorus pesticides and pyrethroids, whereas the number of samples with residues of benzilates, phenylamids and triazoles was insufficient to demonstrate any significant effects. An intake calculation showed that the average intake from Italian grapes was 3.9 mu g day......(-1) for pesticides and 21 mu g day(-1) for copper. Correspondingly, the intakes from South African grapes were 2.6 and 5.7 mu g day(-1) respectively. When the total exposure of pesticides from grapes were related to acceptable daily intake, expressed as the sum of Hazard Quotients, the exposure were...

  5. Characterization of ferric arsenate-sulfate compounds: Implications for arsenic control in refractory gold processing residues

    Czech Academy of Sciences Publication Activity Database

    Paktunc, D.; Majzlan, J.; Palatinus, Lukáš; Dutrizac, J.; Klementová, Mariana; Poirier, G.

    2013-01-01

    Roč. 98, č. 4 (2013), s. 554-565 ISSN 0003-004X Institutional support: RVO:68378271 Keywords : arsenic * ferric arsenate sulfate * autoclave residue * hydrometallurgy Subject RIV: DB - Geology ; Mineralogy Impact factor: 2.059, year: 2013

  6. USAGE OF ALGAE SPECIES CHAETOMORPHA GRACILIS AND CH. AEREA FOR DEPURATION PROCESS OF THE RESIDUAL WATERS

    Directory of Open Access Journals (Sweden)

    SALARU VICTOR

    2008-11-01

    Full Text Available Rapid increase of the population on the globe scale imposes maximum exploration of the natural resources and first of all of the aquatic resources. As a result are obtained an enormous quantity of residual waters which pollute the waters from rivers, lakes, freatic and underground waters. Elaboration of the depuration methods for residual waters the quantity of which grows continuously, is one of the most up to dated issue of the world. The physical-chemical depuration methods of the residual waters are very expensive and lack the efficiency we would like to have. The most efficient method proved to be the biological method using some species of algae and superior aquatic plants. In our experiences we have involved filamentous green algae Chaetomorpha gracilis and Ch. aerea for depuration of the sewerage water from town Cimishlia. The concentration of the mineral nitrogen compounds in the residual water is around 92,5 mg/l, and of the phosphates 10,1 mg/l. There were used the following concentration of the sewerage water: 10%, 25% and 50%. The most intense development of algae Chaetomorpha aerea was observed in the variant with 10% of residual water, in which the total concentration of the nitrogen was 10,24 mg/l, and of the phosphates 1,05 mg/l. For this variant the depuration water level was about 56,9%. For the case with Chaetomorpha gracilis, the depuration level for the same concentration of the residual water constituted 55,9 %. Increase of the concentration of the polluted water inhibits development of the algae reducing to the minimum their capacity to assimilate the nitrogen and the phosphor. In the solutions with 50 % of residual waters, the algae didn't die, but at the same time they didn't develop. From this results that both algae may be used in the phytoamelioration of the residual waters being diluted at 10% with purified water.

  7. Effect of handling and processing on pesticide residues in food- a review

    OpenAIRE

    Bajwa, Usha; Sandhu, Kulwant Singh

    2011-01-01

    Pesticides are one of the major inputs used for increasing agricultural productivity of crops. The pesticide residues, left to variable extent in the food materials after harvesting, are beyond the control of consumer and have deleterious effect on human health. The presence of pesticide residues is a major bottleneck in the international trade of food commodities. The localization of pesticides in foods varies with the nature of pesticide molecule, type and portion of food material and envir...

  8. Techniques for the recovery of residues from uranium ore processing plants

    International Nuclear Information System (INIS)

    Croizat, G.; Lauret, G.

    1996-01-01

    The techniques for recovering residues used at Crouzille (Haute-Vienne, France) by Cogema have now been perfected. Feedback from experience results in a reliable methodology, providing that there is prior size grading of the products to recover, and regular removal of surface waters. About 23500 tons of uranium have been extracted in about 40 years from surface or underground sites in a granitic environment. The treatment of uranium ores has generated about 13.7 millions of tons of residues distributed in four disposal sites. This paper gives an inventory of the chemical and radiological characteristics of the residues and a description of the disposal sites geometry. The recovering methodology involves specific preparation depending on the lithology and the mechanical properties of the residues. Zones characterized by weak lift muddy residues require a geo-textile and a welded wire netting protection beneath the dead cover to avoid mud raising. This precaution implies additional costs but allows to start the recovering a few month after residues drying which is an important economical advantage. (J.S.). 3 figs., 4 photos

  9. Improving the shotbalsting process for making crossbow springs using x-ray diffraction for measuring residual strength

    Directory of Open Access Journals (Sweden)

    Héctor Hernández

    2004-09-01

    Full Text Available Different residual strenght profiles were measured by X-Ray diffraction in areas close to the sufrace of AISI-SAE 5160H steel used in making crossbow springs. Different shotblasting conditions were used and an experimental design was developed for finding process conditions offering suitable Almen intensity and residual strength profile when compression was applied. The combination of variables was chosen which tended to present the most suitable results within the parameters used in making springs in the same conditions, cycle them and determine their behaviour in fatigue tests.

  10. Recovery of arabinan in acetic acid-catalyzed hydrothermal pretreatment on corn stover

    DEFF Research Database (Denmark)

    Xu, Jian; Hedegaard, Mette Christina; Thomsen, Anne Belinda

    2009-01-01

    Acetic acid-catalyzed hydrothermal pretreatment was done on corn stover under 195 °C, 15 min with the acetic acid ranging from 5 × 10−3 to 0.2 g g−1 corn stover. After pretreatment, the water-insoluble solids (WISs) and liquors were collected respectively. Arabinan recoveries from both WIS...

  11. Xylitol production from DEO hydrolysate of corn stover by Pichia stipitis YS-30

    Science.gov (United States)

    Rita C.L.B. Rodrigues; William R. Kenealy; Thomas W. Jeffries

    2011-01-01

    Corn stover that had been treated with vapor-phase diethyl oxalate released a mixture of mono-and oligosaccharides consisting mainly of xylose and glucose. Following overliming and neutralization, a D-xylulokinase mutant of Pichia stipitis, FPL-YS30 (xyl3 -Ä1), converted the stover hydrolysate into xylitol. This research examined the effects of phosphoric or gluconic...

  12. Alkaline peroxide pretreatment of corn stover for enzymatic saccharification and ethanol production

    Science.gov (United States)

    Alkaline hydrogen peroxide (AHP) pretreatment and enzymatic saccharification were evaluated for conversion of corn stover cellulose and hemicellulose to fermentable sugars. Corn stover used in this study contained 37.0±0.2% cellulose, 26.8±0.2% hemicellulose and 18.0±0.1% lignin on dry basis. Unde...

  13. Conversion of sorghum stover into animal feed with white-rot fungi ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-03-15

    Mar 15, 2010 ... white-rot fungi: Pleurotus ostreatus and Pleurotus ... the fungal treatment of sorghum (Sorghum bicolor) stover with two white-rot fungi in a solid state ..... Rumen degradation and In vitro gas production parameters in some browse forages, grasses and maize stover from Kenya. J. Food Agric. Environ.

  14. Photography - Determination of thiosulphate and other residual chemicals in processed photographic films, plates and papers - Methylene blue photometric method and silver sulphide densitometric method

    CERN Document Server

    International Organization for Standardization. Geneva

    1977-01-01

    Photography - Determination of thiosulphate and other residual chemicals in processed photographic films, plates and papers - Methylene blue photometric method and silver sulphide densitometric method

  15. Research on residual stress inside Fe-Mn-Si shape memory alloy coating by laser cladding processing

    Science.gov (United States)

    Ju, Heng; Lin, Cheng-xin; Zhang, Jia-qi; Liu, Zhi-jie

    2016-09-01

    The stainless Fe-Mn-Si shape memory alloy (SMA) coating was prepared on the surface of AISI 304 stainless steel. The principal residual stress measured by the mechanical hole-drilling method indicates that the Fe-Mn-Si SMA cladding specimen possesses a lower residual stress compared with the 304 stainless steel cladding specimen. The mean stress values of the former and the latter on 10-mm-thick substrate are 4.751 MPa and 7.399 MPa, respectively. What's more, their deformation values on 2-mm-thick substrate are about 0° and 15°, respectively. Meanwhile, the variation trend and the value of the residual stress simulated by the ANSYS finite element software consist with experimental results. The X-ray diffraction (XRD) pattern shows ɛ-martensite exists in Fe-Mn-Si SMA coating, which verifies the mechanism of low residual stress. That's the γ→ɛ martensite phase transformation, which relaxes the residual stress of the specimen and reduces its deformation in the laser cladding processing.

  16. Effects of residual feed intake classification and method of alfalfa processing on ewe intake and growth.

    Science.gov (United States)

    Redden, R R; Surber, L M M; Grove, A V; Kott, R W

    2014-02-01

    The objective of this research was to evaluate the effects of residual feed intake (RFI) determined under ad libitum feeding conditions on DMI and performance of yearling ewes fed either chopped or pelleted alfalfa hay. In Exp. 1, 45 ewe-lambs had ad libitum access to a pelleted grower diet for 63 d and individual DMI was determined using an electronic feed delivery system. Residual feed intake values were assigned to each ewe-lamb as a measure of feed efficiency. Sixteen ewe-lambs with the most positive RFI values were classified as high RFI (inefficient) and 16 ewe-lambs with the most negative RFI values were classified as low RFI (efficient). In Exp. 2, half of the ewes from each efficiency group were placed into 1 of 2 pens and provided ad libitum access to either pelleted or chopped alfalfa hay. Individual DMI was again determined using an electronic feed delivery system. Body weight, LM area (LMA), and 12th-rib back fat thickness (BF) were measured at the beginning and end of both experiments. In Exp. 1, DMI by ewe-lambs in the low RFI group was 9% less (P = 0.01) than by ewe-lambs in the high RFI group (2.21 vs. 2.43 kg/d); however, ADG and initial and final BW, LMA, and BF did not differ (P > 0.27) among RFI groups. In Exp. 2, there were no feed processing × RFI group interactions (P > 0.14) for any trait. By design, RFI values were lower (P ewes in the low than high RFI group (-0.27 vs. 0.27); however, RFI values did not differ (P = 1.0) between yearling ewes fed chopped versus pelleted alfalfa. Dry matter intake was 22% less (P ewes in the low than high RFI group (2.5 vs. 3.2 kg/d) and 59% less (P ewes fed chopped versus pelleted alfalfa (2.2 vs. 3.5 kg/d). Initial and final BW, ADG, and G:F did not differ (P > 0.45) between RFI groups but were greater (P ewes fed pelleted alfalfa compared to chopped alfalfa. Final LMA did not differ (P = 0.77) between RFI groups, but final BF tended to be greater (P = 0.06) for high than low RFI yearling ewes (0.63 vs

  17. Radiation processing studies on residual fractions of Olowi petroleum crude oil

    International Nuclear Information System (INIS)

    Sarfo, A.K.

    2011-01-01

    Residual fuel oil is an inexpensive boiler fuel that can replace diesel in some industrial boilers. The viscous waxy nature of residual fuel oil makes it very difficult to use in industries where fuel storage tanks have no heating elements to keep the fuel at temperatures at which it would easily flow. Irradiation is currently being studied as a cost effective means of cracking heavy petroleum crude oil into lighter and more valuable products. Research has shown that irradiation can replace the conventional methods of cracking petroleum with economical benefits. Gamma radiation from a cobalt-60 source was applied to the residue obtained after refining crude oil in this research study, with the intention of causing a similar cracking phenomenon. The main objective of the study was to evaluate the possibility of using gamma radiation to reduce the viscosity of residual fractions of crude oil used as residual fuel oil. This was done by exposing samples of residual fuel oil in glass jars to 9 different doses of gamma radiation, at room temperature and an elevated temperature of 60 degrees Celsius to determine and quantify the effect of radiation on residual fuel oil obtained from the Tema Oil Refinery. The pour points of the irradiated samples were not affected by radiation doses up to 200 kGy while the changes in viscosity for irradiation at room temperature were not significant. Irradiation at 60 degrees Celsius induced a small but significant increase in viscosity at 1 kGy and 200 kGy absorbed doses of irradiation. Irradiation fuels were stable in relation to viscosity, density and pour point over a period of 20 days after exposure. The flash point of irradiated samples, however, decreased by 5.26, 10.53 and 11.34% for 30, 50 and 80 kGy absorbed doses of radiation respectively. Cumulative and continuous doses gave similar results for pour point, density, viscosity and flash point measurements up to 50 kGy. Comparative cost analysis of methods used in maintaining low

  18. Development of separation process of Dy, Y, Tm and Yb from heavier rare earth residue by solvent impregnated resin

    International Nuclear Information System (INIS)

    Shibata, J.; Matsumoto, S.

    1998-01-01

    Full text: Heavier rare earth which is contained in a small amount in ores such as bastnesite and monazite has been accumulated as heavier rare earth residue without doing separation and purification due to lack of suitable methods. The heavier rare earth residue includes seven rare earth elements such as Tb, Dy, Ho, Y, Er, Tm and Yb. Separation and recovery process of Dy, Y, Tm and Yb from leached solution of the heavier rare earth residue was investigated by using a column method with a solvent impregnated resin. The solvent impregnated resin was prepared by impregnation of organophosphorous extractant whose trade name is PC-88A into a macro porous resin, Amberlite XAD-7. It was almost impossible to separate them in simple adsorption and elution steps. However, we attained to individually separate Dy, Y, Tm and Yb from the leached solution first by changing eluent concentration gradually from pH 2 to 2mol/ l HCl in the elution step, and secondly by using a development column and changing eluent concentration in the elution step. The separation process flow was proposed for heavier rare earth residue by using the solvent impregnated resin method

  19. Effect of an absorbent overlay on the residual stress field induced by laser shock processing on aluminum samples

    Energy Technology Data Exchange (ETDEWEB)

    Rubio-Gonzalez, C. [Centro de Ingenieria y Desarrollo Industrial, Pie de la Cuesta No. 702, Desarrollo San Pablo, Queretaro, Qro. 76130 (Mexico)]. E-mail: crubio@cidesi.mx; Gomez-Rosas, G. [Departamento de Ciencias Exactas y Tecnologicas, Centro Universitario de los Lagos, Universidad de Guadalajara. Lagos de Moreno Jal. (Mexico); Ocana, J.L. [Departamento de Fisica Aplicada a la Ingenieria Industrial, E.T.S.I.I. Universidad Politecnica de Madrid (Spain); Molpeceres, C. [Departamento de Fisica Aplicada a la Ingenieria Industrial, E.T.S.I.I. Universidad Politecnica de Madrid (Spain); Banderas, A. [Centro de Ingenieria y Desarrollo Industrial, Pie de la Cuesta No. 702, Desarrollo San Pablo, Queretaro, Qro. 76130 (Mexico); Porro, J. [Departamento de Fisica Aplicada a la Ingenieria Industrial, E.T.S.I.I. Universidad Politecnica de Madrid (Spain); Morales, M. [Departamento de Fisica Aplicada a la Ingenieria Industrial, E.T.S.I.I. Universidad Politecnica de Madrid (Spain)

    2006-07-15

    Laser shock processing (LSP) or laser shock peening is a new technique for strengthening metals. This process induces a compressive residual stress field, which increases fatigue crack initiation life and reduces fatigue crack growth rate. Specimens of 6061-T6 aluminum alloy are used in this investigation. A convergent lens is used to deliver 2.5 J, 8 ns laser pulses by a Q-switch Nd:YAG laser, operating at 10 Hz. The pulses are focused to a diameter of 1.5 mm onto aluminum samples. Density of 2500 pulses/cm{sup 2} with infrared (1064 nm) radiation was used. The effect of an absorbent overlay on the residual stress field using this LSP setup and this energy level is evaluated. Residual stress distribution as a function of depth is assessed by the hole drilling method. It is observed that the overlay makes the compressive residual stress profile move to the surface. This effect is explained on the basis of the vaporization of the coat layer suppressing thermal effects on the metallic substrate. The effect of coating the specimen surface before LSP treatment may have advantages on improving wear and contact fatigue properties of this aluminum alloy.

  20. Occurrence and distribution study of residues from pesticides applied under controlled conditions in the field during rice processing.

    Science.gov (United States)

    Pareja, Lucía; Colazzo, Marcos; Pérez-Parada, Andrés; Besil, Natalia; Heinzen, Horacio; Böcking, Bernardo; Cesio, Verónica; Fernández-Alba, Amadeo R

    2012-05-09

    The results of an experiment to study the occurrence and distribution of pesticide residues during rice cropping and processing are reported. Four herbicides, nine fungicides, and two insecticides (azoxystrobin, byspiribac-sodium, carbendazim, clomazone, difenoconazole, epoxiconazole, isoprothiolane, kresoxim-methyl, propanil, quinclorac, tebuconazole, thiamethoxam, tricyclazole, trifloxystrobin, λ-cyhalotrin) were applied to an isolated rice-crop plot under controlled conditions, during the 2009-2010 cropping season in Uruguay. Paddy rice was harvested and industrially processed to brown rice, white rice, and rice bran, which were analyzed for pesticide residues using the original QuEChERS methodology and its citrate variation by LC-MS/MS and GC-MS. The distribution of pesticide residues was uneven among the different matrices. Ten different pesticide residues were found in paddy rice, seven in brown rice, and eight in rice bran. The highest concentrations were detected in paddy rice. These results provide information regarding the fate of pesticides in the rice food chain and its safety for consumers.

  1. Survey of pesticide residues in table grapes: Determination of processing factors, intake and risk assessment

    DEFF Research Database (Denmark)

    Poulsen, Mette Erecius; Hansen, H.K.; Sloth, Jens Jørgen

    2007-01-01

    , no significant effect was found for organophosphorus pesticides and pyrethroids, whereas the number of samples with residues of benzilates, phenylamids and triazoles was insufficient to demonstrate any significant effects. An intake calculation showed that the average intake from Italian grapes was 3.9 mu g day...

  2. Thermal stability of antiparasitic macrocyclic lactones milk residues during industrial processing.

    Science.gov (United States)

    Imperiale, F A; Farias, C; Pis, A; Sallovitz, J M; Lifschitz, A; Lanusse, C

    2009-01-01

    The chemical stability of residues of different antiparasitic macrocyclic lactone compounds in milk subjected to thermal treatment was assessed. Concentrations of ivermectin (IVM), moxidectin (MXD) and eprinomectin (EPM) in sheep milk, equivalent to those measured in vivo in milk excretion studies, were subjected to 65 degrees C over 30 min or to 75 degrees C for 15 s. Residue concentrations of IVM, MXD and EPM in milk were measured by high-performance liquid chromatography (HPLC) (fluorescence detection) before and after heat treatment of the drug-fortified milk samples. No evidence of chemical loss was obtained in either of the thermal treatments under evaluation. The stability of the parent compounds in milk was evidenced by the lack of bioconversion products (metabolites) after both thermal treatments. Only very minor changes on drug concentrations were observed at the end of the treatments, which fell within the limits of the variation of the validated analytical method. In conclusion, residue concentrations of macrocyclic lactones are unaffected by industrial-simulated milk thermal procedures. Based on the reported findings, it can be postulated that residue concentrations of IVM, MXD and EPM measured in raw sheep milk may be used to estimate consumer exposure and dietary intake for these veterinary drugs.

  3. DOE's process and implementation guidance for decommissioning, deactivation, decontamination, and remedial action of property with residual contamination

    International Nuclear Information System (INIS)

    Domotor, S.; Peterson, H. Jr.; Wallo, A. III

    1999-01-01

    This paper presents DOE's requirements, process, and implementation guidance for the control and release of property that may contain residual radioactive material. DOE requires that criteria and protocols for release of property be approved by DOE and that such limits be selected using DOE's As Low as is Reasonably Achievable (ALARA) process. A DOE Implementation Guide discusses how the levels and details (e.g., cleanup volumes, costs of surveys, disposal costs, dose to workers and doses to members of the public, social and economic factors) of candidate release options are to be evaluated using DOE's ALARA process. Supporting tools and models for use within the analysis are also highlighted. (author)

  4. The effect of initial stress induced during the steel manufacturing process on the welding residual stress in multi-pass butt welding

    Directory of Open Access Journals (Sweden)

    Jeong-ung Park

    2018-03-01

    Full Text Available A residual stress generated in the steel structure is broadly categorized into initial residual stress during manufacturing steel material, welding residual stress caused by welding, and heat treatment residual stress by heat treatment. Initial residual stresses induced during the manufacturing process is combined with welding residual stress or heat treatment residual stress, and remained as a final residual stress. Because such final residual stress affects the safety and strength of the structure, it is of utmost importance to measure or predict the magnitude of residual stress, and to apply this point on the design of the structure. In this study, the initial residual stress of steel structures having thicknesses of 25 mm and 70 mm during manufacturing was measured in order to investigate initial residual stress (hereinafter, referred to as initial stress. In addition, thermal elastic plastic FEM analysis was performed with this initial condition, and the effect of initial stress on the welding residual stress was investigated. Further, the reliability of the FE analysis result, considering the initial stress and welding residual stress for the steel structures having two thicknesses, was validated by comparing it with the measured results. In the vicinity of the weld joint, the initial stress is released and finally controlled by the weld residual stress. On the other hand, the farther away from the weld joint, the greater the influence of the initial stress. The range in which the initial stress affects the weld residual stress was not changed by the initial stress. However, in the region where the initial stress occurs in the compressive stress, the magnitude of the weld residual compressive stress varies with the compression or tension of the initial stress. The effect of initial stress on the maximum compression residual stress was far larger when initial stress was considered in case of a thickness of 25 mm with a value of 180

  5. Evaluation of continuous ethanol fermentation of dilute-acid corn stover hydrolysate using thermophilic anaerobic bacterium Thermoanaerobacter BG1L1

    DEFF Research Database (Denmark)

    Georgieva, Tania I.; Ahring, Birgitte Kiær

    2007-01-01

    fermented yielding ethanol of 0.39–0.42 g/g-sugars consumed. Xylose was nearly completely utilized (89–98%) for PCS up to 10% TS, whereas at 15% TS, xylose conversion was lowered to 67%. The reactor was operated continuously for 135 days, and no contamination was seen without the use of any agent......Dilute sulfuric acid pretreated corn stover is potential feedstock of industrial interest for second generation fuel ethanol production. However, the toxicity of corn stover hydrolysate (PCS) has been a challenge for fermentation by recombinant xylose fermenting organisms. In this work...... for preventing bacterial infections. This study demonstrated that the use of immobilized thermophilic anaerobic bacteria for continuous ethanol fermentation could be promising in a commercial ethanol process in terms of system stability to process hardiness and reactor contamination. The tested microorganism has...

  6. Process design of in situ esterification-transesterifica tion for biodiesel production from residual oil of spent bleaching earth (SBE)

    Science.gov (United States)

    Suryani, A.; Mubarok, Z.; Suprihatin; Romli, M.; Yunira, E. N.

    2017-05-01

    Indonesia is the largest producer of Crude Palm Oil (CPO) in the world. CPO refining process produces spent bleaching earth (SBE), which still contains 20-30% oil. This residual oil is very potential to be developed as a biodiesel feedstock. The purpose of this research was to develop an in situbiodiesel production process of residual oil of SBE, which covered stirring speed of esterification and transesterification and also transesterification time to produce biodiesel with the best characteristics. The production was conducted in a 100 L reactor. The stirring speeds applied were 650 rpm and 730 rpm, and the transesterification time varied at 60, 90 and 120 minutes. The combination of 730 rpm stirring speed for 90 minutes transesterification resulted in the best biodiesel characteristics with the yield of 85%, the specific energy of 6,738 kJ/kg and the heater efficiency of 48%. The physico-chemical properties of biodiesel was in conformity with the SNI of Biodiesel.

  7. NMR Studies on Key Residues That Affect Phosphorylation and Dephosphorylation Processes of Bacterial Response Regulator RR468

    Directory of Open Access Journals (Sweden)

    WANG Dan

    2017-12-01

    Full Text Available Response regulator proteins are important components of the two-component signal transduction systems, and essential in transferring the signal delivered from the sensor histidine kinase and eliciting an adaptive response. Phosphorylation and dephosphorylation of the response regulator proteins determine the direction of the signal transduction process. The phosphorylation and dephosphorylation sites of the response regulator proteins play an important role in exerting their function. Here we studied some key residues of response regulator RR468 from Thermotoga maritima. Site-directed mutagenesis experiments were performed to the key sites M55 and K85, which are located in loop b3-a3 and loop b4-a4, respectively. The structure and dynamics feature of the two mutants were investigated with liquid nuclear magnetic resonance (NMR spectroscopy. The results of functional experiments demonstrated that the two residues could affect the phosphorylation and dephosphorylation processes.

  8. Development and application of the water vapour nitrogen (WVN) process for sodium residues removal at the prototype fast reactor, dounreay

    International Nuclear Information System (INIS)

    Gunn, J.B.; Mason, L.; Husband, W.; Macdonald, A.J.; Smith, M.R.

    2009-01-01

    The decommissioning programme for the United Kingdom Atomic Energy Authority's two fast reactors at Dounreay is currently at the early implementation stage. UKAEA embarked upon an extensive development programme in 1994, to qualify the water vapour nitrogen (WVN) process for treating alkali metal residues. The aim of this programme was to identify a safe operational envelope that could be applied to a wide range of residue types and specific reactor geometries. Four stages of the development programme have been completed. The first stage was an extensive programme of approximately 100 small-scale tests. The second stage involved pilot scale tests up to 10 kg. The third stage involved the formation of an alliance of five companies and construction of an industrial pilot scale facility, for up to 1 000 kg, at Janetstown, ten miles from Dounreay. The fourth stage refined the process by cleaning actual sodium residues within various storage vessels and the secondary sodium circuits, with the aim of having a robust process for cleaning the reactor vessel. This paper summarizes the tests and the potential solutions too many of the issues identified during the course of the development programme. It also covers the lessons learnt from completing the cleaning of the storage vessels and secondary circuits. Finally, the next stage is also discussed. This covers the construction of a new on-site facility to clean vessels and plant items with tritiated sodium residues and further on-going development of the WVN process for cleaning the reactor vessel, in the quest to avoid unstable reactions. (author)

  9. Determination of residual stresses and natural frequencies of roll-tensioned disc by a dynamic simulation of the rolling process

    Science.gov (United States)

    Skordaris, G.; Bouzakis, K.-D.; Tasoulas, D.

    2017-02-01

    Roll tensioning is a common method for increasing locally the superficial strength of thin circular saws and in this way their dynamic stability. Through roll tensioning, residual stresses are induced into the disc material leading to a significant enhancement of its dynamic stiffness. In this paper, a FEM-methodology is proposed for determining the developed residual stresses in the discs after rolling and for investigating their effects on the circular saw natural frequencies. More specifically, a 3D-FEM model was developed for the dynamic simulation of the rolling process on circular saws, using the LS-DYNA software. This model enables the explicit determination of the developed residual stresses in the roll-tensioned discs. Furthermore, the natural frequencies of the pre-stressed circular saws were calculated by the ANSYS software. In these calculations, the already determined residual stresses were taken into consideration. Different distances of the roll-tensioned zone from the disc centre were taken into account for estimating their effect on the disc’s natural frequencies. By the proposed methodology, optimum roll-tensioning conditions can be predicted for improving the dynamic behaviour of thin circular saws during cutting.

  10. EFFECT OF UREA-MOLASSES BLOCK SUPPLEMENTATION ON NUTRIENT DIGESTIBILITY AND INTAKE OF AMMONIATED MAIZE STOVERS IN COW -CALVES

    Directory of Open Access Journals (Sweden)

    M. Usman Faizi, M.M. Siddiqui and G. Habib

    2004-01-01

    Full Text Available An experiment was conducted in a 4x4 Latin square design with four cow-calves {Holstein Friesian, aged' 6-8 months to investigate the effect of supplementing molasses-urea block {MUB to untreated or ammoniated maize stovers on feed intake and in viva digestibility of nutrients. Each period consisted of 10 days adaptation, followed by five days data collection. The four diets were untreated maize stovers {Diet A, untreated maize stovers with MUB {Diet B, ammoniated maize stovers {Diet 'C and ammoniated maize stovers with MUB {Diet D. Daily consumption of maize stovers and total feed by the calves were higher {P< 0.01 on the diets containing ammoniated maize stovers than those containing untreated maize stovers. Ammoniation increased the intake of maize stovers by 61 %. Supplementary feeding of MUB did not change the daily intake of both untreated and ammoniated maize stovers. Calves receiving untreated maize stovers consumed more MUB {P< 0.01 than those given ammoniated maize stovers {496.40 vs 180.20g DM/d. Daily water consumption was affected {P< 0.01 by diets and was lowest on Diet A. Calves receiving ammoniated maize stovers consumed more water than those given untreated maize stovers. MUB increased {P<0.01 the water consumption only on untreated maize stovers. Mean water consumption was 13.93, 15.91, 15.07 and 15.60 lit/d on diet A, B, C and D, respectively. In vivo digestibility of dry matter, organic matter and crude protein were Influenced {P<0.01 by diet composition. I Among the four diets, dry matter digestibility was minimum (P< 0.01 on Diet A and remained the same on diets B, C and D {55.82, 58.02 and 58.14%, respectively. Organic matter and crude protein digestibility were higher in the claves receiving ammoniated maize stovers. Supplementation of MUB increased (P< 0.01 the digestibility of all the three nutrients in untreated maize stovers but did not affect the digestibility of ammoniated maize stovers. The results demonstrated

  11. Corn fiber, cobs and stover: enzyme-aided saccharification and co-fermentation after dilute acid pretreatment.

    Science.gov (United States)

    Van Eylen, David; van Dongen, Femke; Kabel, Mirjam; de Bont, Jan

    2011-05-01

    Three corn feedstocks (fibers, cobs and stover) available for sustainable second generation bioethanol production were subjected to pretreatments with the aim of preventing formation of yeast-inhibiting sugar-degradation products. After pretreatment, monosaccharides, soluble oligosaccharides and residual sugars were quantified. The size of the soluble xylans was estimated by size exclusion chromatography. The pretreatments resulted in relatively low monosaccharide release, but conditions were reached to obtain most of the xylan-structures in the soluble part. A state of the art commercial enzyme preparation, Cellic CTec2, was tested in hydrolyzing these dilute acid-pretreated feedstocks. The xylose and glucose liberated were fermented by a recombinant Saccharomyces cerevisiae strain. In the simultaneous enzymatic saccharification and fermentation system employed, a concentration of more than 5% (v/v) (0.2g per g of dry matter) of ethanol was reached. Copyright © 2011 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2017-11-10

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

  13. Effect of Tip Shape of Frictional Stir Burnishing Tool on Processed Layer’s Hardness, Residual Stress and Surface Roughness

    Directory of Open Access Journals (Sweden)

    Yoshimasa Takada

    2018-01-01

    Full Text Available Friction stir burnishing (FSB is a surface-enhancement method used after machining, without the need for an additional device. The FSB process is applied on a machine that uses rotation tools (e.g., machining center or multi-tasking machine. Therefore, the FSB process can be applied immediately after the cutting process using the same machine tool. Here, we apply the FSB to the shaft materials of 0.45% C steel using a multi-tasking machine. In the FSB process, the burnishing tool rotates at a high-revolution speed. The thin surface layer is rubbed and stirred as the temperature is increased and decreased. With the FSB process, high hardness or compressive residual stress can be obtained on the surface layer. However, when we applied the FSB process using a 3 mm diameter sphere tip shape tool, the surface roughness increased substantially (Ra = 20 µm. We therefore used four types of tip shape tools to examine the effect of burnishing tool tip radius on surface roughness, hardness, residual stress in the FSB process. Results indicated that the surface roughness was lowest (Ra = 10 µm when the tip radius tool diameter was large (30 mm.

  14. Current and potential sustainable corn stover feedstock for biofuel production in the United States

    Science.gov (United States)

    Tan, Zhengxi; Liu, Shu-Guang; Tieszen, Larry L.; Bliss, Norman

    2012-01-01

    Increased demand for corn (Zea mays L.) stover as a feedstock for cellulosic ethanol raises concerns about agricultural sustainability. Excessive corn stover harvesting could have long-term impacts on soil quality. We estimated current and future stover production and evaluated the potential harvestable stover amount (HSA) that could be used for biofuel feedstock in the United States by defining the minimum stover requirement (MSR) associated with the current soil organic carbon (SOC) content, tillage practices, and crop rotation systems. Here we show that the magnitude of the current HSA is limited (31 Tg y−1, dry matter) due to the high MSR for maintaining the current SOC content levels of soils that have a high carbon content. An alternative definition of MSR for soils with a moderate level of SOC content could significantly elevate the annual HSA to 68.7 Tg, or even to 132.2 Tg if the amount of currently applied manure is counted to partially offset the MSR. In the future, a greater potential for stover feedstock could come from an increase in stover yield, areal harvest index, and/or the total planted area. These results suggest that further field experiments on MSR should be designed to identify differences in MSR magnitude between maintaining SOC content and preventing soil erosion, and to understand the role of current SOC content level in determining MSR from soils with a wide range of carbon contents and climatic conditions.

  15. Prediction of process induced shape distortions and residual stresses in large fibre reinforced composite laminates

    DEFF Research Database (Denmark)

    Nielsen, Michael Wenani

    The present thesis is devoted to numerical modelling of thermomechanical phenomena occurring during curing in the manufacture of large fibre reinforced polymer matrix composites with thick laminate sections using vacuum assisted resin transfer moulding (VARTM). The main application of interest...... in this work is modelling manufacturing induced shape distortions and residual stresses in commercial wind turbine composite blades. Key mechanisms known to contribute to shape distortions and residual stress build-up are reviewed and the underlying theories used to model these mechanisms are presented....... The main mechanisms of thermal-, chemical- and mechanical origin are; (i) the thermal expansion mismatch of the constitutive composite materials, layer and tooling, (ii) chemical cure shrinkage of the composite matrix material and (iii) the tooling (i.e. the mould, inserts etc.) influence on the composite...

  16. Modeling and Parameter Optimization for Surface Roughness and Residual Stress in Dry Turning Process

    Directory of Open Access Journals (Sweden)

    M. H. El-Axir

    2017-10-01

    Full Text Available The influence of some turning variables and tool overhang on surface roughness parameters and residual stress induced due to machining 6061-T6 aluminum alloy is investigated in this paper. Four input parameters (cutting speed, feed rate, depth of cut and tool overhang are considered. Tests are carried out by precision turning operation on a lathe. Design of experiment techniques, i.e. response surface methodology (RSM and Taguchi's technique have been used to accomplish the objective of the experimental study. Surface roughness parameters are measured using a portable surface roughness device while residual stresses are measured employing deflection-etching technique using electrochemical analysis. The results obtained reveal that feed and rotational speed play significant role in determining the average surface roughness. Furthermore, the depth of cut and tool overhang are less significant parameters, whereas tool overhang interacts with feed rate. The best result of surface roughness was obtained using low or medium values of overhang with low speed and /or feed rate. Minimum maximum tensile residual stress can be obtained with a combination of tool overhang of 37 mm with very low depth of cut, low rotational speed and feed rate of 0.188 mm/rev.

  17. Sequential high gravity ethanol fermentation and anaerobic digestion of steam explosion and organosolv pretreated corn stover.

    Science.gov (United States)

    Katsimpouras, Constantinos; Zacharopoulou, Maria; Matsakas, Leonidas; Rova, Ulrika; Christakopoulos, Paul; Topakas, Evangelos

    2017-11-01

    The present work investigates the suitability of pretreated corn stover (CS) to serve as feedstock for high gravity (HG) ethanol production at solids-content of 24wt%. Steam explosion, with and without the addition of H 2 SO 4 , and organosolv pretreated CS samples underwent a liquefaction/saccharification step followed by simultaneous saccharification and fermentation (SSF). Maximum ethanol concentration of ca. 76g/L (78.3% ethanol yield) was obtained from steam exploded CS (SECS) with 0.2% H 2 SO 4 . Organosolv pretreated CS (OCS) also resulted in high ethanol concentration of ca. 65g/L (62.3% ethanol yield). Moreover, methane production through anaerobic digestion (AD) was conducted from fermentation residues and resulted in maximum methane yields of ca. 120 and 69mL/g volatile solids (VS) for SECS and OCS samples, respectively. The results indicated that the implementation of a liquefaction/saccharification step before SSF employing a liquefaction reactor seemed to handle HG conditions adequately. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Technical and economical analyses of combined heat and power generation from distillers grains and corn stover in ethanol plants

    International Nuclear Information System (INIS)

    Wang Lijun; Hanna, Milford A.; Weller, Curtis L.; Jones, David D.

    2009-01-01

    The technical and economical feasibilities of a novel integrated biomass gasification and fuel cell combined heat and power (CHP) system were analyzed for supplying heat and power in an ethanol plant from distillers grains (DG) and corn stover. In a current dry-grind plant with an annual production capacity of 189 million liters (50 million gallons) of ethanol, the energy cost for ethanol production using natural gas at a price of 6.47 US$/GJ for processing heat and commercial grid at a price of 0.062 US$/kWh for electrical power supply was 0.094 US$/liter. If the integrated CHP system using wet DG with 64.7% moisture on a wet basis at 105 US$/dry tonne and corn stover with 20% moisture at 30 US$/dry tonne as feedstock was used to supply heat and power in the ethanol plant, the energy costs for ethanol production would be 0.101 US$/liter and 0.070 US$/liter, which are 107% and 75% of the current energy cost for ethanol production, respectively. To meet the demand of processing heat and power in the ethanol plant, the integrated CHP system required 22.1 dry tonnes of corn stover with 20% moisture or 14.5 dry tonnes of DG with 64.7% moisture on a wet basis per hour, compared with the available 18.8 dry tonnes of DG per hour in the ethanol plant. High-value chemicals such as policosanols, phytosterols and free fatty acids can be extracted out of the raw DG to reduce the cost of DG as a feedstock of the integrated CHP system. The energy cost for ethanol production using the integrated CHP system with corn stover and DG as the feedstock for supplying heat and power can be reduced further by increasing ethanol production scale, decreasing the moisture content of biomass feedstock, and decreasing thermal energy to electricity output ratio of the CHP system. In terms of the energy efficiency of the integrated CHP system and the energy cost for ethanol production, the moisture content of the feedstock going into the integrated CHP should be lower than 70% on a wet basis.

  19. Chemical analysis and biorefinery of red algae Kappaphycus alvarezii for efficient production of glucose from residue of carrageenan extraction process.

    Science.gov (United States)

    Masarin, Fernando; Cedeno, Fernando Roberto Paz; Chavez, Eddyn Gabriel Solorzano; de Oliveira, Levi Ezequiel; Gelli, Valéria Cress; Monti, Rubens

    2016-01-01

    Biorefineries serve to efficiently utilize biomass and their by-products. Algal biorefineries are designed to generate bioproducts for commercial use. Due to the high carbohydrate content of algal biomass, biorefinery to generate biofuels, such as bioethanol, is of great interest. Carrageenan is a predominant polysaccharide hydrocolloid found in red macroalgae and is widely used in food, cosmetics, and pharmaceuticals. In this study, we report the biorefinery of carrageenan derived from processing of experimental strains of the red macroalgae Kappaphycus alvarezii. Specifically, the chemical composition and enzymatic hydrolysis of the residue produced from carrageenan extraction were evaluated to determine the conditions for efficient generation of carbohydrate bioproducts. The productivity and growth rates of K. alvarezii strains were assessed along with the chemical composition (total carbohydrates, ash, sulfate groups, proteins, insoluble aromatics, galacturonic acid, and lipids) of each strain. Two strains, brown and red, were selected based on their high growth rates and productivity and were treated with 6 % KOH for extraction of carrageenan. The yields of biomass from treatment with 6 % KOH solution of the brown and red strains were 89.3 and 89.5 %, respectively. The yields of carrageenan and its residue were 63.5 and 23 %, respectively, for the brown strain and 60 and 27.8 %, respectively, for the red strain. The residues from the brown and red strains were assessed to detect any potential bioproducts. The galactan, ash, protein, insoluble aromatics, and sulfate groups of the residue were reduced to comparable extents for the two strains. However, KOH treatment did not reduce the content of glucan in the residue from either strain. Glucose was produced by enzymatic hydrolysis for 72 h using both strains. The glucan conversion was 100 % for both strains, and the concentrations of glucose from the brown and red strains were 13.7 and 11.5 g L(-1

  20. Application of residual polysaccharide-degrading enzymes in dried shiitake mushrooms as an enzyme preparation in food processing.

    Science.gov (United States)

    Tatsumi, E; Konishi, Y; Tsujiyama, S

    2016-11-01

    To examine the activities of residual enzymes in dried shiitake mushrooms, which are a traditional foodstuff in Japanese cuisine, for possible applications in food processing. Polysaccharide-degrading enzymes remained intact in dried shiitake mushrooms and the activities of amylase, β-glucosidase and pectinase were high. A potato digestion was tested using dried shiitake powder. The enzymes reacted with potato tuber specimens to solubilize sugars even under a heterogeneous solid-state condition and that their reaction modes were different at 38 and 50 °C. Dried shiitake mushrooms have a potential use in food processing as an enzyme preparation.

  1. Drying of sicilian lemon residue: influence of process variables on the evaluation of the dietary fiber produced

    OpenAIRE

    Silva,Vanessa Martins; Viotto,Luiz Antonio

    2010-01-01

    In this study, the effect of the process variables of the air-drying of Sicilian lemon residues on some technological properties of the fibers produced was studied. The determination and modeling of desorption isotherms were used to establish the equilibrium moisture content at 60, 75, and 90 °C using the static method with 8 saturated salt solutions. The best fit was obtained with BET and GAB models. The drying process was conducted in a vertical tray dryer and delineated according to a cent...

  2. Effect of the spray volume adjustment model on the efficiency of fungicides and residues in processing tomato

    Directory of Open Access Journals (Sweden)

    Henryk Ratajkiewicz

    2016-08-01

    Full Text Available This study compared the effects of a proportionate spray volume (PSV adjustment model and a fixed model (300 L/ha on the infestation of processing tomato with potato late blight (Phytophthora infestans (Mont. de Bary (PLB and azoxystrobin and chlorothalonil residues in fruits in three consecutive seasons. The fungicides were applied in alternating system with or without two spreader adjuvants. The proportionate spray volume adjustment model was based on the number of leaves on plants and spray volume index. The modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS method was optimized and validated for extraction of azoxystrobin and chlorothalonil residue. Gas chromatography with a nitrogen and phosphorus detector and an electron capture detector were used for the analysis of fungicides. The results showed that higher fungicidal residues were connected with lower infestation of tomato with PLB. PSV adjustment model resulted in lower infestation of tomato than the fixed model (300 L/ha when fungicides were applied at half the dose without adjuvants. Higher expected spray interception into the tomato canopy with the PSV system was recognized as the reasons of better control of PLB. The spreader adjuvants did not have positive effect on the biological efficacy of spray volume application systems. The results suggest that PSV adjustment model can be used to determine the spray volume for fungicide application for processing tomato crop.

  3. Effect of the spray volume adjustment model on the efficiency of fungicides and residues in processing tomato

    Energy Technology Data Exchange (ETDEWEB)

    Ratajkiewicz, H.; Kierzek, R.; Raczkowski, M.; Hołodyńska-Kulas, A.; Łacka, A.; Wójtowicz, A.; Wachowiak, M.

    2016-11-01

    This study compared the effects of a proportionate spray volume (PSV) adjustment model and a fixed model (300 L/ha) on the infestation of processing tomato with potato late blight (Phytophthora infestans (Mont.) de Bary) (PLB) and azoxystrobin and chlorothalonil residues in fruits in three consecutive seasons. The fungicides were applied in alternating system with or without two spreader adjuvants. The proportionate spray volume adjustment model was based on the number of leaves on plants and spray volume index. The modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method was optimized and validated for extraction of azoxystrobin and chlorothalonil residue. Gas chromatography with a nitrogen and phosphorus detector and an electron capture detector were used for the analysis of fungicides. The results showed that higher fungicidal residues were connected with lower infestation of tomato with PLB. PSV adjustment model resulted in lower infestation of tomato than the fixed model (300 L/ha) when fungicides were applied at half the dose without adjuvants. Higher expected spray interception into the tomato canopy with the PSV system was recognized as the reasons of better control of PLB. The spreader adjuvants did not have positive effect on the biological efficacy of spray volume application systems. The results suggest that PSV adjustment model can be used to determine the spray volume for fungicide application for processing tomato crop. (Author)

  4. Assessment of agroforestry residue potentials for the bioeconomy in the European Union.

    Science.gov (United States)

    Thorenz, Andrea; Wietschel, Lars; Stindt, Dennis; Tuma, Axel

    2018-03-01

    The biobased chemical industry is characterised by strong growth. Innovative products and materials such as biopolymers have been developed, and current European demand for biopolymers exceeds the domestic supply. Agroforestry residues can serve as main sources of the basic building blocks for chemicals and materials. This work assesses sustainably available agroforestry residues to feed a high added-value materials and product bioeconomy. To evaluate bioeconomic potential, a structured three-step approach is applied. Cultivation practices, sustainability issues, legislative restrictions, technical limitations and competitive applications are considered. All data regarding bioeconomic potential are processed on a regional level and mapped by ArcGIS. Our results identify wheat straw as the most promising source in the agricultural sector, followed by maize stover, barley straw and rape straw, which all contain a total concentration of lignocellulose of more than 80% of dry matter. In the forestry sector, residue bark from two coniferous species, spruce and pine, is the most promising source, with approximately 70% lignocellulose. Additionally, coniferous bark contains considerable amounts of tannin, which has attracted increasing interest for industrial utilisation. A sensitivity analysis concerning removal rates, residue-to-crop ratios, changes in farming technologies and competing applications is applied at the end of the study to consolidate our results.

  5. Single cell oil production byTrichosporon cutaneumfrom steam-exploded corn stover and its upgradation for production of long-chain α,ω-dicarboxylic acids.

    Science.gov (United States)

    Zhao, Chen; Fang, Hao; Chen, Shaolin

    2017-01-01

    Single cell oil (SCO) production from lignocelluloses by oleaginous microorganisms is still high in production cost, making the subsequent production of biofuels inviable economically in such an era of low oil prices. Therefore, how to upgrade the final products of lignocellulose-based bioprocess to more valuable ones is becoming a more and more important issue. Differently sourced cellulases were compared in the enzymatic hydrolysis of the steam-exploded corn stover (SECS) and the cellulase from the mixed culture of Trichoderma reesei and Aspergillus niger was found to have the highest enzymatic hydrolysis yield 86.67 ± 4.06%. Three-stage enzymatic hydrolysis could greatly improve the efficiency of the enzymatic hydrolysis of SECS, achieving a yield of 74.24 ± 2.69% within 30 h. Different bioprocesses from SECS to SCO were compared and the bioprocess C with the three-stage enzymatic hydrolysis was the most efficient, producing 57.15 g dry cell biomass containing 31.80 g SCO from 327.63 g SECS. An efficient and comprehensive process from corn stover to long-chain α,ω-dicarboxylic acids (DCAs) was established by employing self-metathesis, capable of producing 6.02 g long-chain DCAs from 409.54 g corn stover and 6.02 g alkenes as byproducts. On-site cellulase production by the mixed culture of T. reesei and A. niger is proven the most efficient in providing cellulase to the lignocellulose-based bioprocess. Three-stage enzymatic hydrolysis was found to have very good application value in SCO production by Trichosporon cutaneum from SECS. A whole process from corn stover to long-chain DCAs via a combination of biological and chemical approaches was successfully established and it is an enlightening example of the comprehensive utilization of agricultural wastes.

  6. Studi Awal Desain Pabrik Bioetanol dari Corn stover

    Directory of Open Access Journals (Sweden)

    Gumelar Ahmad Muhlis

    2015-12-01

    Full Text Available Jagung (Zea mays merupakan tanaman pangan yang penting di Indonesia. Pada tahun 2006, luas panen jagung adalah 3,5 juta hektar dengan produksi rata-rata 3,47ton/ha, produksi jagung secara nasional 11,7 juta ton. Limbah batang dan daun jagung kering adalah 3,46 ton/ha sehingga limbah pertanian yang dihasilkan sekitar 12.1juta ton. Potensi energi limbah pada komoditas jagung sangat besar dan diharapkan akan terus meningkat sejalan dengan program pemerintah dalam meningkatkan produksi jagung secara nasional yaitu program pengembangan peternakan secara terintegrasi (Crop Livestock System/CLS. Oleh karena itu, optimasi pemanfaatan limbah jagung sangat diperlukan untuk mendapatkan keuntungan yang optimal sehingga dalam studi ini diputuskan pemanfaatan sebanyak 50% limbah pertanian jagung yang ada di Kab. Tuban untuk selanjutnya diproses menjadi Bioetanol 95%. Ketersediaan bahan baku, letak strategis, transportasi yang mudah terletak di jalur pantura dan langsung terhubung dengan pelabuhan, serta potensi tenaga kerja yang cukup menjanjikan menjadikan alasan dalam pemilihan Kawasan Industri Kec. Jenu Kab. Tuban sebagai lokasi pabrik. Proses pembuatan bioetanol dari corn stover dengan proses fermentasi dibagi menjadi 4 tahap yaitu:  penyimpanan dan penanganan bahan baku, hidrolisis, fermentasi, dan pemurnian. Desain konseptual yang disajikan mengacu pada Technical Report Pilot Plan National Renewable Energy Laboratory tahun 2011. Pabrik Bioetanol direncanakan dapat mengolah 484.625 ton corn stover kering/hari pada yield etanol (303 L/dry ton dengan kapasitas produksi etanol 95% sebanyak 44.226 kL/tahun, harga jual adalah Rp13.500,00/L. Masa konstruksi pabrik yang didirikan 2 tahun dengan pembiayaan berupa modal tetap (FCI Rp. 515.854.121.170; modal kerja (WCI Rp. 91.033.080.207; investasi total (TCI Rp. 606.887.201.377 ; total production cost (TPC Rp. 345.715.009.709. Sehingga didapatkan IRR 23,37 % pertahun ;pay out time (POT 6,98 tahun dengan project

  7. Microbial dynamics in anaerobic digestion reactors for treating organic urban residues during the start-up process.

    Science.gov (United States)

    Alcántara-Hernández, R J; Taş, N; Carlos-Pinedo, S; Durán-Moreno, A; Falcón, L I

    2017-06-01

    Anaerobic digestion of organic residues offers economic benefits via biogas production, still methane (CH 4 ) yield relies on the development of a robust microbial consortia for adequate substrate degradation, among other factors. In this study, we monitor biogas production and changes in the microbial community composition in two semi-continuous stirred tank reactors during the setting process under mesophilic conditions (35°C) using a 16S rDNA high-throughput sequencing method. Reactors were initially inoculated with anaerobic granular sludge from a brewery wastewater treatment plant, and gradually fed organic urban residues (4·0 kg VS m -3  day -1 ) . The inocula and biomass samples showed changes related to adaptations of the community to urban organic wastes including a higher relative proportion of Clostridiales, with Ruminococcus spp. and Syntrophomonas spp. as recurrent species. Candidatus Cloacamonas spp. (Spirochaetes) also increased from ~2·2% in the inoculum to >10% in the reactor biomass. The new community consolidated the cellulose degradation and the propionate and amino acids fermentation processes. Acetoclastic methanogens were more abundant in the reactor, where Methanosaeta spp. was found as a key player. This study demonstrates a successful use of brewery treatment plant granular sludge to obtain a robust consortium for methane production from urban organic solid waste in Mexico. This study describes the selection of relevant bacteria and archaea in anaerobic digesters inoculated with anaerobic granular sludge from a brewery wastewater treatment plant. Generally, these sludge granules are used to inoculate reactors digesting organic urban wastes. Though, it is still not clearly understood how micro-organisms respond to substrate variations during the reactor start-up process. After feeding two reactors with organic urban residues, it was found that a broader potential for cellulose degradation was developed including Bacteroidetes

  8. Engineering, Nutrient Removal, and Feedstock Conversion Evaluations of Four Corn Stover Harvest Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Reed L. Hoskinson; Douglas L. Karlen; Stuart J. Birrell; Corey W. Radtke; W.W. Wilhelm

    2007-02-01

    Crop residue has been identified as a near-term source of biomass for renewable fuel, heat, power, chemicals and other bio-materials. Replicated plots were established in a corn (Zea mays L.) field near Ames, IA to evaluate four harvest scenarios (low cut, high-cut top, high-cut bottom, and normal cut). A prototype one-pass harvest system was used to collect the residue samples. High-cut top and high-cut bottom samples were obtained from the same plots in two separate operations. Chemical composition, dilute acid pretreatment response, ethanol conversion efficiency and gasification parameters for each scenario were determined. Mean grain yield (10.1 Mg ha-1 dry weight) was representative of the area. The four harvest scenarios removed 6.7, 4.9, 1.7, and 5.1 Mg ha-1 of dry matter. Expressed as harvest indices (HI) the values were 0.60 for low cut, 0.66 for normal cut, and 0.61 for the total high-cut (top + bottom) scenarios, which are probably realistic for machine harvest and current hybrids. The macro-nutrient replacement value for the normal harvest scenario under our conditions was $57.36 ha-1 or $11.27 Mg-1. Harvesting stalk bottoms increased the water content, the risk of combine damage, the transportation costs, and left insufficient soil cover, while also producing a problematic feedstock. Harvesting stover at current combine height (~40 cm) would be best for farmers and ethanol producers because of better harvest speed and efficiency as well as the quality of the ethanol feedstock.

  9. Bioethanol from corn stover – a review and technical assessment of alternative biotechnologies

    DEFF Research Database (Denmark)

    Zhao, Yan; Damgaard, Anders; Christensen, Thomas Højlund

    2018-01-01

    , conversion efficiencies and material consumption, we were able to quantify the material flows for each technological configuration and estimate the uncertainty of the flows. The eight technological configurations produced 11–22% ethanol from the dry solid content of the corn stover. Technologies using......Reviewing the literature from the last decade regarding the bioconversion of corn stover into ethanol, 474 references were identified containing 561 datasets. We found 144 datasets which were sufficiently consistent and detailed to address the current state of the art of corn stover conversion...... largely identical in all datasets, albeit a range of operating conditions was reported. The final distillation of the ethanol was very rarely included in the datasets. By parameterising the bioethanol production by 26 parameters, including corn stover compositions, solid loadings, operational conditions...

  10. Comparison of residual monomer loss from cold-cure orthodontic acrylic resins processed by different polymerization techniques.

    Science.gov (United States)

    Nik, Tahereh Hosseinzadeh; Shahroudi, Atefe Saffar; Eraghihzadeh, Zeinab; Aghajani, Farzaneh

    2014-03-01

    This investigation aimed to assess and compare the amount of residual monomer (RM) released from removable orthodontic appliances constructed by sprinkle-on and dough techniques. One hundred and twenty acrylic samples were prepared from orthodontic autopolymerized acrylic resins and divided into three groups, according to the processing method: sprinkle-on with polyclave, sprinkle-on without polyclave and dough technique. After polymerization, the specimens of each group were immersed in distilled water for 24 h, 48 h, 72 h and 1 week. High-performances liquid chromatography (HPLC) was utilized to measure residual monomer content. Maximum observed RM was 1284·91±129·07 ppm measured for sprinkle-on technique without polyclave after 24 h of water immersion. At this time, the level of RM was significantly different among the three applied techniques (Psprinkle-on technique with polyclave released the least amount of RM. Within each group, the maximum monomer releasing was observed after the first 24 h and decreases were observed in subsequent time groups. The reduction over the time was not significant in the polyclave groups (P>0·05). The sprinkle-on technique with polyclave and longer water immersion reduced residual monomer released from acrylic orthodontic appliances.

  11. Agricultural residue valorization using a hydrothermal process for second generation bioethanol and oligosaccharides production.

    Science.gov (United States)

    Vargas, Fátima; Domínguez, Elena; Vila, Carlos; Rodríguez, Alejandro; Garrote, Gil

    2015-09-01

    In the present work, the hydrothermal valorization of an abundant agricultural residue has been studied in order to look for high added value applications by means of hydrothermal pretreatment followed by fed-batch simultaneous saccharification and fermentation, to obtain oligomers and sugars from autohydrolysis liquors and bioethanol from the solid phase. Non-isothermal autohydrolysis was applied to barley straw, leading to a solid phase with about a 90% of glucan and lignin and a liquid phase with up to 168 g kg(-1) raw material valuable hemicellulose-derived compounds. The solid phase showed a high enzymatic susceptibility (up to 95%). It was employed in the optimization study of the fed-batch simultaneous saccharification and fermentation, carried out at high solids loading, led up to 52 g ethanol/L (6.5% v/v). Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Characterization of açaí (E. oleracea fruits and its processing residues

    Directory of Open Access Journals (Sweden)

    José Dalton Cruz Pessoa

    2010-12-01

    Full Text Available The aim of this work was to study the source of the açaí residue for its possible commercial applications by characterizing the fruit (fresh and dry mass, and performing an anatomic study of the pericarp from which were identified the origin of the anthocyanins, and fatty acids, and fibers; also the vascular system, its fibers constituents and fibrils were characterized. It was concluded that anthocyanins were located on the epiderm and external parenchyma, and that solids retained on the sieve come from the sclerenchyma, and that the fatty acids come from the storage parenchyma. The vascular tissue was formed by the fibers around 20 mm length. The length distribution of the fibrils had a mean length of 580µm.

  13. The Effect of Organic Phosphorus and Nitrogen Enriched Manure on Nutritive Value of Sweet Corn Stover

    Science.gov (United States)

    Lukiwati, D. R.; Pujaningsih, R. I.; Murwani, R.

    2018-02-01

    The experiment aimed to evaluate the effect of some manure enriched with phosphorus (P) and nitrogen (N) organic (‘manure plus’) on crude protein and mineral production of sweet corn (Zea mays saccharata)and quality of fermented stover as livestock feed. A field experiment was conducted on a vertisol soil (low pH, nitrogen and low available Bray II extractable P). Randomized block design with 9 treatments in 3 replicates was used in this experiment. The treatments were T1(TSP), T2 (SA), T3 (TSP+SA), T4 (manure), T5 (manure+PR), T6 (manure+guano), T7 (manure+N-legume), T8 (manure+PR+N-legume), T9 (manure +guano+N-legume). Data were analyzed using analysis of variance (ANOVA) and the differences between treatment means were examined by Duncan Multiple Range Test (DMRT). Results of the experiment showed that the treatment significantly affected to the crude protein and calcium production of stover and nutrient concentration of fermented stover, but it is not affected to P production of stover. The result of DMRT showed that the effect of ‘manure plus’ was not significantly different on CP and Ca production of stover, mineral concentration, in vitro DMD and OMD of fermented stover, compared to inorganic fertilization. Conclusion, manure enriched with organic NP, resulted in similar on CP and Ca production of stover and nutrient concentration of fermented stover compared to inorganic fertilizer. Thus, organic-NP enriched manure could be an alternative and viable technology to utilize low grade of phosphate rock, guano and Gliricidea sepium to produce sweet corn in vertisol soil.

  14. Resource assessment and removal analysis for corn stover and wheat straw in the Eastern and Midwestern United States - rainfall and wind-induced soil erosion methodology

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, R.G. [Enersol Resources, Manhattan, KS (United States)

    2002-05-01

    The focus of this study was to develop a methodology to estimate 'hectare-weighted', county-level, corn stover and spring and winter wheat straw removable residue quantities in the USA for 1995-1997 in 37 states (north-south line from North Dakota to Texas and all states east) such that tolerable rainfall and wind soil loss limits were not exceeded.The methodology developed and employed in this study was based on the revised universal soil loss equation (RUSLE) and the wind erosion equation (WEQ), which were used to predict individual county-level corn or wheat yields required at harvest to insure that the amount of soil loss would not exceed the tolerable soil loss limit. These yields were then compared to actual county-level corn or wheat yields to determine the quantity of removable residue. Results of this study indicate an annual average of over 42 and 8 million metric tons of corn stover and straw (spring and winter wheat), respectively (46.2 and 8.8 million tons) were potentially available for removal between 1995 and 1997 in these 37 states. (Author)

  15. Performance of a biogas upgrading process based on alkali absorption with regeneration using air pollution control residues.

    Science.gov (United States)

    Baciocchi, Renato; Carnevale, Ennio; Costa, Giulia; Gavasci, Renato; Lombardi, Lidia; Olivieri, Tommaso; Zanchi, Laura; Zingaretti, Daniela

    2013-12-01

    This work analyzes the performance of an innovative biogas upgrading method, Alkali absorption with Regeneration (AwR) that employs industrial residues and allows to permanently store the separated CO2. This process consists in a first stage in which CO2 is removed from the biogas by means of chemical absorption with KOH or NaOH solutions followed by a second stage in which the spent absorption solution is contacted with waste incineration Air Pollution Control (APC) residues. The latter reaction leads to the regeneration of the alkali reagent in the solution and to the precipitation of calcium carbonate and hence allows to reuse the regenerated solution in the absorption process and to permanently store the separated CO2 in solid form. In addition, the final solid product is characterized by an improved environmental behavior compared to the untreated residues. In this paper the results obtained by AwR tests carried out in purposely designed demonstrative units installed in a landfill site are presented and discussed with the aim of verifying the feasibility of this process at pilot-scale and of identifying the conditions that allow to achieve all of the goals targeted by the proposed treatment. Specifically, the CO2 removal efficiency achieved in the absorption stage, the yield of alkali regeneration and CO2 uptake resulting for the regeneration stage, as well as the leaching behavior of the solid product are analyzed as a function of the type and concentration of the alkali reagent employed for the absorption reaction. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Cogeneration Technology Alternatives Study (CTAS). Volume 6: Computer data. Part 2: Residual-fired nocogeneration process boiler

    Science.gov (United States)

    Knightly, W. F.

    1980-01-01

    About fifty industrial processes from the largest energy consuming sectors were used as a basis for matching a similar number of energy conversion systems that are considered as candidate which can be made available by the 1985 to 2000 time period. The sectors considered included food, textiles, lumber, paper, chemicals, petroleum, glass, and primary metals. The energy conversion systems included steam and gas turbines, diesels, thermionics, stirling, closed cycle and steam injected gas turbines, and fuel cells. Fuels considered were coal, both coal and petroleum based residual and distillate liquid fuels, and low Btu gas obtained through the on site gasification of coal. Computer generated reports of the fuel consumption and savings, capital costs, economics and emissions of the cogeneration energy conversion systems (ECS's) heat and power matched to the individual industrial processes are presented. National fuel and emissions savings are also reported for each ECS assuming it alone is implemented. Two nocogeneration base cases are included: coal fired and residual fired process boilers.

  17. Effect of crop sequence and crop residues on soil C, soil N and yield of maize

    International Nuclear Information System (INIS)

    Shafi, M.; Bakht, J.; Attaullah; Khan, M.A.

    2010-01-01

    Improved management of nitrogen (N) in low N soils is critical for increased soil productivity and crop sustainability. The objective of the present study was to evaluate the effects of residues incorporation, residues retention on soil surface as mulch, fertilizer N and legumes in crop rotation on soil fertility and yield of maize (Zea may L.). Fertilizer N was applied to maize at the rate of 160 kg ha/sup -1/, and to wheat at the rate of 120 kg ha/sup -1/ or no fertilizer N application. Crop rotation with the sequence of maize after wheat (Triticum aestivum L.), maize after lentil (Lens culinaris Medic) or wheat after mash bean (Vigna mungo L.) arranged in a split plot design was followed. Post-harvest incorporation of crop residues and residues retention on soil surface as mulch had significantly (p=0.05) affected grain and stover yield during 2004 and 2005. Two years average data revealed that grain yield was increased by 3.31 and 6.72% due to mulch and residues incorporation. Similarly, stover yield was also enhanced by 5.39 and 10.27% due to the same treatment respectively. Mulch and residues incorporation also improved stover N uptake by 2.23 and 6.58%, respectively. Total soil N and organic matter was non significantly (p=0.05) increased by 5.63 and 2.38% due to mulch and 4.13, 7.75% because of crop residues incorporation in the soil. Maize grain and stover yield responded significantly (p=0.05) to the previous legume (lentil) crop when compared with the previous cereal crop (wheat). The treatment of lentil - maize(+N), on the average, increased grain yield of maize by 15.35%, stover yield by 16.84%, total soil N by 10.31% and organic matter by 10.17%. Similarly, fertilizer N applied to the previous wheat showed carry over effect on grain yield (6.82%) and stover yield (11.37%) of the following maize crop. The present study suggested that retention of residues on soil surface as mulch, incorporation of residues in soil and legume (lentil - maize) rotation

  18. Corn stover harvest strategy effects on grain yield and soil quality indicators

    International Nuclear Information System (INIS)

    Douglas, K.; Stuart, B.; Adam, W.

    2013-01-01

    Developing strategies to collect and use cellulo sic biomass for bio energy production is important because those materials are not used as human food sources. This study compared corn (Zea mays L.) stover harvest strategies on a 50 ha Clarion- Nicol let-Webster soil Association site near Emmetsburg, Iowa, USA. Surface soil samples (0 to 15 cm) were analyzed after each harvest to monitor soil organic carbon (Soc), ph, phosphorus (P) and potassium (K) changes. Grain yields in 2008, before the stover harvest treatments were imposed, averaged 11.4 Mg ha-1. In 2009, 2010, and 2011 grain yields averaged 10.1, 9.7, and 9.5 Mg ha-1, respectively. Although grain yields after stover harvest strategies imposed were lower than in 2008, there were no significant differences among the treatments. Four-year average stover collection rates ranged 1.0 to 5.2 Mg ha-1 which was 12 to 60% of the above-ground biomass. Soc showed a slight decrease during the study, but the change was not related to any specific stover harvest treatment. Instead, we attribute the Soc decline to the tillage intensity and lower than expected crop yields. Overall, these results are consistent with other Midwestern USA studies that indicate corn stover should not be harvested if average grain yields are less than 11 Mg ha-1

  19. An Agent-Based Modeling Approach for Determining Corn Stover Removal Rate and Transboundary Effects

    Science.gov (United States)

    Gan, Jianbang; Langeveld, J. W. A.; Smith, C. T.

    2014-02-01

    Bioenergy production involves different agents with potentially different objectives, and an agent's decision often has transboundary impacts on other agents along the bioenergy value chain. Understanding and estimating the transboundary impacts is essential to portraying the interactions among the different agents and in the search for the optimal configuration of the bioenergy value chain. We develop an agent-based model to mimic the decision making by feedstock producers and feedstock-to-biofuel conversion plant operators and propose multipliers (i.e., ratios of economic values accruing to different segments and associated agents in the value chain) for assessing the transboundary impacts. Our approach is generic and thus applicable to a variety of bioenergy production systems at different sites and geographic scales. We apply it to the case of producing ethanol using corn stover in Iowa, USA. The results from the case study indicate that stover removal rate is site specific and varies considerably with soil type, as well as other factors, such as stover price and harvesting cost. In addition, ethanol production using corn stover in the study region would have strong positive ripple effects, with the values of multipliers varying with greenhouse gas price and national energy security premium. The relatively high multiplier values suggest that a large portion of the value associated with corn stover ethanol production would accrue to the downstream end of the value chain instead of stover producers.

  20. Handling of corn stover bales for combustion in small and large furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Morissette, R.; Savoie, P.; Villeneuve, J. [Agriculture and Agri-Food Canada, Quebec City, PQ (Canada)

    2010-07-01

    This paper reported on a study in which dry corn stover was baled and burned in 2 furnaces in the province of Quebec. Small and large rectangular bale formats were considered for direct combustion. The first combustion unit was a small 500,000 BTU/h dual chamber log wood furnace located at a hay growing farm in Neuville, Quebec. The heat was initially transferred to a hot water pipe system and then transferred to a hot air exchanger to dry hay bales. The small stover bales were placed directly into the combustion furnace. The low density of the bales compared to log wood, required filling up to 8 times more frequently. Stover bales produced an average of 6.4 per cent ash on a DM basis and required an automated system for ash removal. Combustion gas contained levels of particulate matter greater than 1417 mg/m{sup 3}, which is more than the local acceptable maximum of 600 mg/m{sup 3} for combustion furnaces. The second combustion unit was a high capacity 12.5 million BTU/h single chamber furnace located in Saint-Philippe-de-neri, Quebec. It was used to generate steam for a feed pellet mill. Large corn stover bales were broken up and fed on a conveyor and through a screw auger to the furnace. The stover was light compared to the wood chips used in this furnace. For mechanical reasons, the stover could not be fed continuously to the furnace.

  1. Availability of corn stover as a sustainable feedstock for bioethanol production.

    Science.gov (United States)

    Kadam, Kiran L; McMillan, James D

    2003-05-01

    The amount of corn stover that can be sustainably collected is estimated to be 80-100 million dry tonnes/yr (t/yr), a majority of which would be available to ethanol plants in the near term as only a small portion is currently used for other applications. Potential long-term demand for corn stover by non-fermentative applications in the United States is estimated to be about 20 million dry t/yr, assuming that corn stover-based products replace 50% of both hardwood pulp and wood-based particleboard, and that 50% of all furfural production is from corncobs. Hence, 60-80 million dry t/yr of corn stover should be available to fermentative routes. To achieve an ethanol production potential of 11 billion L (3 billion gal) per year (a target level for a non-niche feedstock), about 40% of the harvestable corn stover is needed. This amount should be available as long as the diversion of corn stover to non-ethanol fermentative products remains limited.

  2. Residual mean first-passage time for jump processes: theory and applications to Levy flights and fractional Brownian motion

    International Nuclear Information System (INIS)

    Tejedor, V; Benichou, O; Voituriez, R; Metzler, Ralf

    2011-01-01

    We derive a functional equation for the mean first-passage time (MFPT) of a generic self-similar Markovian continuous process to a target in a one-dimensional domain and obtain its exact solution. We show that the obtained expression of the MFPT for continuous processes is actually different from the large system size limit of the MFPT for discrete jump processes allowing leapovers. In the case considered here, the asymptotic MFPT admits non-vanishing corrections, which we call residual MFPT. The case of Levy flights with diverging variance of jump lengths is investigated in detail, in particular, with respect to the associated leapover behavior. We also show numerically that our results apply with good accuracy to fractional Brownian motion, despite its non-Markovian nature.

  3. Potential use of cowpea (Vigna unguiculata (L.) Walp.) stover treated with white-rot fungi as rabbit feed.

    Science.gov (United States)

    Andrade, Ederson; Pinheiro, Victor; Gonçalves, Alexandre; Cone, John W; Marques, Guilhermina; Silva, Valéria; Ferreira, Luis; Rodrigues, Miguel

    2017-10-01

    Lignin inhibitory effects within the cell wall structure constitute a serious drawback in maximizing the utilization of fibrous feedstuffs in animal feeding. Therefore treatments that promote efficient delignification of these materials must be applied. This study evaluated the potential of white-rot fungi to upgrade the nutritive value of cowpea stover for rabbit feeding. There was an increase in the crude protein content of all substrates as a result of fungi treatments, reaching a net gain of 13% for Pleurotus citrinopileatus incubation. Overall, net losses of dry and organic matter occurred during fungi treatments. Although the fiber content remained identical, higher consumption of cell wall contents was measured for P. citrinopileatus incubation (between 40 and 45%). The incubation period did not influence lignin degradation for any of the fungi treatments. Differences within the fungal degradation mechanisms indicate that P. citrinopileatus treatment was most effective, enhancing in vitro organic matter digestibility by around 30% compared with the control. Treatment of cowpea stover with P. citrinopileatus led to an efficient delignification process which resulted in higher in vitro organic matter digestibility, showing its potential in the nutritional valorization of this feedstuff. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  4. Natural binders and solid bridge type binding mechanisms in briquettes and pellets made from corn stover and switchgrass.

    Science.gov (United States)

    Kaliyan, Nalladurai; Morey, R Vance

    2010-02-01

    Corn stover and switchgrass are two important feedstocks considered for producing renewable fuels and energy in the US. Densification of these biomass feedstocks into briquettes/pellets would help reduce the problems and costs of bulk transportation, handling, and storage of biomass feedstocks. In this study, the role of the natural binders in corn stover and switchgrass to make durable particle-particle bonding in briquettes/pellets was investigated by micro-structural analyses. Scanning Electron Microscopy (SEM) images of briquettes made by using a uniaxial piston-cylinder densification apparatus in the laboratory, briquettes made by using a pilot-scale roll-press briquetting machine, and pellets made by using a pilot-scale conventional ring-die pelleting machine were analysed. The SEM images showed that the bonding between particles was created mainly through solid bridges. The solid bridges between particles were made by natural binders in the biomass expressed during the densification process. UV auto-fluorescence images of briquettes and pellets further confirmed that the solid bridges were made mainly by natural binders such as lignin and protein. It was found that activating (softening) the natural binders using moisture and temperature in the range of glass transition is important to make durable particle-particle bonding.

  5. A combined sodium phosphate and sodium sulfide pretreatment for enhanced enzymatic digestibility and delignification of corn stover.

    Science.gov (United States)

    Qing, Qing; Zhou, Linlin; Guo, Qi; Huang, Meizi; He, Yucai; Wang, Liqun; Zhang, Yue

    2016-10-01

    Na3PO4 and Na2S were employed as efficient alkaline catalysts for the pretreatment of corn stover. To systematically obtain optimal conditions, the effects of critical pretreatment parameters including sodium phosphate concentration (1-4%), sulfidity (0-20%), pretreatment temperature (100-120°C), and reaction time (20-60min) on the reducing sugar yield of pretreated substrates were evaluated in a lab-scale using the response surface methodology. Pretreated under the sodium phosphate concentration of 4%, sulfidity of 10%, temperature of 120°C, and reaction time of 40min, the reducing sugar yield and glucose yield of the pretreated corn stover achieved 91.11% and 64.01%, respectively, with a moderate enzyme loading of 30FPU/g substrate. Additionally, a strong correlation (R(2)=0.971 and R(2)=0.954) between the delignification and the reducing sugar yield (or glucose yield) was observed by this pretreatment method. These results evidently support that the combined Na3PO4-Na2S pretreatment is an effective and feasible method for processing lignocellulosic biomass. Copyright © 2016. Published by Elsevier Ltd.

  6. A novel diffusion-biphasic hydrolysis coupled kinetic model for dilute sulfuric acid pretreatment of corn stover.

    Science.gov (United States)

    Chen, Longjian; Zhang, Haiyan; Li, Junbao; Lu, Minsheng; Guo, Xiaomiao; Han, Lujia

    2015-02-01

    Kinetic experiments on the dilute sulfuric acid pretreatment of corn stover were performed. A high xylan removal and a low inhibitor concentration were achieved by acid pretreatment. A novel diffusion-hydrolysis coupled kinetic model was proposed. The contribution to the xylose yield was analyzed by the kinetic model. Compared with the inhibitor furfural negatively affecting xylose yield, the fast and slow-hydrolyzing xylan significantly contributed to the xylose yield, however, their dominant roles were dependent on reaction temperature and time. The impact of particle size and acid concentration on the xylose yield were also investigated. The diffusion process may significantly influence the hydrolysis of large particles. Increasing the acid concentration from 0.15 M to 0.30 M significantly improved the xylose yield, whereas the extent of improvement decreased to near-quantitative when further increasing acid loading. These findings shed some light on the mechanism for dilute sulfuric acid hydrolysis of corn stover. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Two stage hydrolysis of corn stover at high solids content for mixing power saving and scale-up applications.

    Science.gov (United States)

    Liu, Ke; Zhang, Jian; Bao, Jie

    2015-11-01

    A two stage hydrolysis of corn stover was designed to solve the difficulties between sufficient mixing at high solids content and high power input encountered in large scale bioreactors. The process starts with the quick liquefaction to convert solid cellulose to liquid slurry with strong mixing in small reactors, then followed the comprehensive hydrolysis to complete saccharification into fermentable sugars in large reactors without agitation apparatus. 60% of the mixing energy consumption was saved by removing the mixing apparatus in large scale vessels. Scale-up ratio was small for the first step hydrolysis reactors because of the reduced reactor volume. For large saccharification reactors in the second step, the scale-up was easy because of no mixing mechanism was involved. This two stage hydrolysis is applicable for either simple hydrolysis or combined fermentation processes. The method provided a practical process option for industrial scale biorefinery processing of lignocellulose biomass. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. SAR Ground Moving Target Indication Based on Relative Residue of DPCA Processing

    Directory of Open Access Journals (Sweden)

    Jia Xu

    2016-10-01

    Full Text Available For modern synthetic aperture radar (SAR, it has much more urgent demands on ground moving target indication (GMTI, which includes not only the point moving targets like cars, truck or tanks but also the distributed moving targets like river or ocean surfaces. Among the existing GMTI methods, displaced phase center antenna (DPCA can effectively cancel the strong ground clutter and has been widely used. However, its detection performance is closely related to the target’s signal-to-clutter ratio (SCR as well as radial velocity, and it cannot effectively detect the weak large-sized river surfaces in strong ground clutter due to their low SCR caused by specular scattering. This paper proposes a novel method called relative residue of DPCA (RR-DPCA, which jointly utilizes the DPCA cancellation outputs and the multi-look images to improve the detection performance of weak river surfaces. Furthermore, based on the statistics analysis of the RR-DPCA outputs on the homogenous background, the cell average (CA method can be well applied for subsequent constant false alarm rate (CFAR detection. The proposed RR-DPCA method can well detect the point moving targets and distributed moving targets simultaneously. Finally, the results of both simulated and real data are provided to demonstrate the effectiveness of the proposed SAR/GMTI method.

  9. Application of processes of advanced oxidation as phenol treatment in industrial residual waters of refinery

    International Nuclear Information System (INIS)

    Forero, Jorge Enrique; Ortiz, Olga Patricia; Rios, Fabian

    2005-01-01

    Although more efficient and economical processes for the treatment of sewage have been developed in recent years, the challenge they are facing-due to the greater knowledge of the effect that pollutants have on the environment, the greater consumption of water because of the development of human and industrial activity and the reduction of fresh water sources indicate that we are far from attaining the final solution. This affirmation specially applies to the pollutants, which are resistant to biological treatment processes, such as most of the aromatic compounds found in sewage of the petrochemical industries. In this document, the processes known as advanced oxidation will be explored. Theses have been reported as having the greatest potential in the treatment of these pollutants. Likewise the results of the application of these technologies with waters typical of the petroleum industry will be reported. These have previously been evaluated with processes of typical ozonization

  10. Residual deposits (residual soil)

    International Nuclear Information System (INIS)

    Khasanov, A.Kh.

    1988-01-01

    Residual soil deposits is accumulation of new formate ore minerals on the earth surface, arise as a result of chemical decomposition of rocks. As is well known, at the hyper genes zone under the influence of different factors (water, carbonic acid, organic acids, oxygen, microorganism activity) passes chemical weathering of rocks. Residual soil deposits forming depends from complex of geologic and climatic factors and also from composition and physical and chemical properties of initial rocks

  11. Soil Hydraulic Properties Influenced by Corn Stover Removal from No-Till Corn in Ohio.

    Energy Technology Data Exchange (ETDEWEB)

    Blanco-Canqui, H.; Lal, Rattan; Post, W. M.; Izaurralde, R Cesar C.; Shipitalo, M. J.

    2007-01-01

    Corn (Zea mays L.) stover removal for biofuel production and other uses may alter soil hydraulic properties, but site-specific information needed to determine the threshold levels of removal for the U.S. Corn Belt region is limited. We quantified impacts of systematic removal of corn stover on soil hydraulic parameters after one year of stover management under no-till (NT) systems in three soils in Ohio including Rayne silt loam (fine-loamy, mixed, mesic Typic Hapludult) at Coshocton, Hoytville clay loam (fine, illitic, mesic Mollic Epiaqualfs) at Hoytville, and Celina silt loam (fine, mixed, active, mesic Aquic Hapludalfs) at South Charleston. Interrelationships among soil properties and saturated hydraulic conductivity (Ksat) predictions were also studied. Earthworm middens, Ksat, bulk density (ρb), soil-water retention (SWR), pore-size distribution, and air permeability (ka) were determined for six stover treatments including 0 (T0), 25 (T25), 50 (T50), 75 (T75), 100 (T100), and 200 (T200) % of corn stover corresponding to 0, 1.25, 2.50, 3.75, 5.00, and 10.00 Mg ha-1 of stover, respectively. Stover removal reduced the number of middens, Ksat, SWR, and ka at all sites (P<0.01). Complete stover removal reduced earthworm middens by 20-fold across sites, decreased geometric mean Ksat from 6.3 to 0.1 mm h-1 at Coshocton, 3.2 to 0.3 mm h-1 at Hoytville, and 5.8 to 0.6 mm h-1 at Charleston, and increased ρb in the 0- to 10-cm depth by about 15% relative to double stover plots. The SWR for T100 was 1.3 times higher than that for T0 at 0 to -6 kPa. The log ka for T200, T100, and T75 significantly exceeded that under T50, T25, and T0 at Coshocton and Charleston. Measured parameters were strongly correlated, and ka was a potential Ksat predictor. Stover harvesting at rates above 1.25 Mg ha-1 affects soil hydraulic properties and earthworm activity, but further monitoring is needed to ascertain the threshold levels of stover removal.Corn (Zea mays L.) stover removal for

  12. Tween 40 pretreatment of unwashed water-insoluble solids of reed straw and corn stover pretreated with liquid hot water to obtain high concentrations of bioethanol.

    Science.gov (United States)

    Lu, Jie; Li, Xuezhi; Yang, Ruifeng; Zhao, Jian; Qu, Yinbo

    2013-11-09

    Liquid hot water (LHW) pretreatment is an effective and environmentally friendly method to produce bioethanol with lignocellulosic materials. In our previous study, high ethanol concentration and ethanol yield were obtained from water-insoluble solids (WIS) of reed straw and corn stover pretreated with LHW by using fed-batch semi-simultaneous saccharification and fermentation (S-SSF). However, high cellulase loading and the large amount of wash water possibly limit the practical application of LHW pretreatment. To decrease cellulase loading and the amount of wash water, we performed Tween 40 pretreatment before WIS was subjected to bioethanol fermentation. Results showed that the optimum conditions of Tween 40 pretreatment were as follows: Tween 40 concentration of 1.5%, WIS-to-Tween 40 ratio of 1:10 (w/v), and pretreatment time of 1 hour at ambient temperature. After Tween 40 pretreatment, cellulase loading could be greatly reduced. After Tween 40 pretreatment, the residual liquid could be recycled for utilization but slightly affected ethanol concentration and yield. The unwashed WIS could obtain a high ethanol concentration of 56.28 g/L (reed straw) and 52.26 g/L (corn stover) by Tween 40 pretreatment using fed-batch S-SSF. Ethanol yield reached a maximum of 69.1% (reed straw) and 71.1% (corn stover). Tween 40 pretreatment was a very effective and less costly method with unwashed WIS. This pretreatment could greatly reduce cellulase loading and save wash water. Higher ethanol concentration was obtained almost without reducing ethanol yield.

  13. 76 FR 69690 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Science.gov (United States)

    2011-11-09

    ... detection of residues by gas chromatography using nitrogen phosphorous detection (GC/NPD). Contact: Andrew..., leafy greens, subgroup 5B at 15 ppm; turnip greens at 15 ppm; corn, sweet, kernel plus cob with husks removed at 0.01 ppm; corn, sweet, forage at 10 ppm; corn, sweet, stover at 30 ppm; vegetable, fruiting...

  14. 78 FR 33785 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Science.gov (United States)

    2013-06-05

    ... chromatography with Nitrogen-Phosphorus detection (GC-NPD) has been developed and validated for residues of..., crop group 14, hulls at 15 ppm; grain, cereal, crop group 15, except rice grain at 4 ppm; sweet corn..., straw at 15 ppm; corn, field, grain at 0.02 ppm; corn, field, forage at 3 ppm; corn, field, stover at 15...

  15. Dedicated energy crops and crop residues for bioenergy feedstocks in the Central and Eastern U.S.A.

    Science.gov (United States)

    Dedicated energy crops and crop residues will meet herbaceous feedstock demands for the new bioeconomy in the Central and Eastern USA. Perennial warm-season grasses and corn stover are well-suited to the eastern half of the USA and provide opportunities for expanding agricultural operations in the r...

  16. Diffusion-bonded 16MND5-Inconel 690-316LN junction: elaboration and process residual stresses modeling

    International Nuclear Information System (INIS)

    Martinez, Michael

    1999-01-01

    The objective of this research thesis is, on the one hand, to elaborate and to characterise a bonded junction of 16MND5 and 316LN steels, and, on the other hand, to develop a simulation tool for the prediction of microstructures after bonding, as well as residual stresses related to this process. The author first reports the study of the use of diffusion bonding by hot isostatic pressing (HIP diffusion bonding) for the bonding of 16MND5 (steel used in French PWR vessel) and 316LN (austenitic stainless steel used in piping), in order to obtain junctions adapted to a use within PWRs. In this case, the use of an Inconel insert material appeared to be necessary to avoid stainless steel carburization. Thus, inserts in Inconel 600 and 690 have been tested. The objective has then been to develop a realistic calculation of residual stresses in this assembly. These stresses are stimulated by quenching. The author notably studied the simulation of temperature dependent phase transformations, and stress induced phase transformations. An existing model is validated and applied to HIP and quenching cycles. The last part reports the calculation of residual stresses by simulation of the mechanical response of the three-component material cooled from 900 C to room temperature and thus submitted to a loading of thermal origin (dilatation) and metallurgical origin (phase transformations in the 16MND5). The effect of carbon diffusion on mechanical properties has also been taken into account. The author discusses problems faced by existing models, and explains the choice of conventional macro-mechanical models. The three materials are supposed to have a plastic-viscoplastic behaviour with isotropic and kinematic strain hardening, and this behaviour is identified between 20 and 900 C [fr

  17. Hydrometallurgical recovery of heavy metals from low grade automobile shredder residue (ASR): An application of advanced Fenton process (AFP).

    Science.gov (United States)

    Singh, Jiwan; Lee, Byeong-Kyu

    2015-09-15

    To investigate the leaching and recovery of heavy metals from low-grade automobile shredder residue (ASR), the effects of nitric acid (HNO3) and hydrogen peroxide (H2O2) concentrations, liquid/solid (L/S) ratio, leaching temperature and ASR particle size fractions on the heavy metal leaching rate were determined. The heavy metals were recovered by fractional precipitation and advanced Fenton process (AFP) at different pHs. The toxicity characteristic leaching procedure (TCLP) test was also performed in the residue remaining after heavy metal leaching to evaluate the potential toxicity of ASR. The heavy metal leaching efficiency was increased with increasing HNO3 and H2O2 concentrations, L/S ratio and temperature. The heavy metal leaching efficiencies were maximized in the lowest ASR size fraction at 303 K and L/S ratio of 100 mL/g. The kinetic study showed that the metal leaching was best represented by a second-order reaction model, with a value of R(2) > 0.99 for all selected heavy metals. The determined activation energy (kJ/mol) was 21.61, 17.10, 12.15, 34.50, 13.07 and 11.45 for Zn, Fe, Ni, Pb, Cd and Cr, respectively. In the final residue, the concentrations of Cd, Cr and Pb were under their threshold limits in all ASR size fractions. Hydrometallurgical metal recovery was greatly increased by AFP up to 99.96% for Zn, 99.97% for Fe, 95.62% for Ni, 99.62% for Pb, 94.11% for Cd and 96.79% for Cr. AFP is highly recommended for the recovery of leached metals from solution even at low concentrations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Process combination of thermo pressure hydrolysis and fermentation for innovative processing of residual biogenous mass; Verfahrenskombination aus Thermodruckhydrolyse und Vergaerung zur innovativen Verwertung biogener Restmassen

    Energy Technology Data Exchange (ETDEWEB)

    Prechtl, S.; Merkl, M.; Schieder, D.; Schneider, R.; Bischof, F. [Applikations- und Technikzentrum fuer Energieverfahrens-, Umwelt- und Stroemungstechnik (ATZ-EVUS), Sulzbach-Rosenberg (Germany)

    1999-07-01

    The described processing technique consisting of topped thermal hydrolysis and downstream fermentation is particularly suitable for wet, low-structure organic waste. High turnover rates at short treatment times permit to minimize residues effectively, yield a fair amount of biogas and allow compact design because of low fermenter volumes, which has a positive impact on investment cost. (orig.) [German] Das vorgestellt Verwertungsverfahren bestehend aus vorgeschalteter thermischer Hydrolyse und nachgeschalteter Vergaerung eignet sich besonders fuer nasse, strukturarme organische Abfaelle. Hohe Umsatzraten bei kurzen Behandlungszeiten ermoeglichen eine gute Reststoffminimierung und Biogasausbeute sowie eine kompakte Bauweise durch kleine Fermentervolumina, was sich positiv auf die Investitionskosten auswirkt. (orig.)

  19. Hybrid-renewable processes for biofuels production: concentrated solar pyrolysis of biomass residues

    Energy Technology Data Exchange (ETDEWEB)

    George, Anthe [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Geier, Manfred [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Dedrick, Daniel E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-10-01

    The viability of thermochemically-derived biofuels can be greatly enhanced by reducing the process parasitic energy loads. Integrating renewable power into biofuels production is one method by which these efficiency drains can be eliminated. There are a variety of such potentially viable "hybrid-renewable" approaches; one is to integrate concentrated solar power (CSP) to power biomass-to-liquid fuels (BTL) processes. Barriers to CSP integration into BTL processes are predominantly the lack of fundamental kinetic and mass transport data to enable appropriate systems analysis and reactor design. A novel design for the reactor has been created that can allow biomass particles to be suspended in a flow gas, and be irradiated with a simulated solar flux. Pyrolysis conditions were investigated and a comparison between solar and non-solar biomass pyrolysis was conducted in terms of product distributions and pyrolysis oil quality. A novel method was developed to analyse pyrolysis products, and investigate their stability.

  20. Degradation of flumequine by the Fenton and photo-Fenton processes: Evaluation of residual antimicrobial activity

    International Nuclear Information System (INIS)

    Rodrigues-Silva, Caio; Maniero, Milena Guedes; Rath, Susanne; Guimarães, José Roberto

    2013-01-01

    Flumequine is a broad-spectrum antimicrobial agent of the quinolone class, and it is widely used as a veterinary drug in food-producing animals. The presence of flumequine in the environment may contribute to the development of drug resistant bacterial strains. In this study, water samples fortified with flumequine (500 μg L −1 ) were degraded using the Fenton and photo-Fenton processes. The maximum degradation efficiency for flumequine by the Fenton process was approximately 40% (0.5 mmol L −1 Fe(II), 2.0 mmol L −1 H 2 O 2 and 15 min). By applying UV radiation (photo-Fenton process), the efficiency reached more than 94% in 60 min when 0.25 mmol L −1 Fe(II) and 10.0 mmol L −1 H 2 O 2 were used. Under these conditions, the Fenton process was able to reduce the biological activity, whereas the photo-Fenton process eliminated almost all of the antimicrobial activity because it was not detected. Four byproducts with an m/z of 244, 238, 220 and 202 were identified by mass spectrometry, and a degradation pathway for flumequine was proposed. The byproducts were derived from decarboxylation and defluorination reactions and from modifications in the alkylamino chain of the fluoroquinolone. - Highlights: ► Photo-Fenton process achieved the maximum performance, degrading 94% of flumequine. ► As the flumequine concentration decreased, antimicrobial activity also decreased. ► Four byproducts with m/z of 244, 238, 220 and 202 were identified. ► A degradation pathway for flumequine was proposed

  1. Degradation of flumequine by the Fenton and photo-Fenton processes: Evaluation of residual antimicrobial activity

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues-Silva, Caio; Maniero, Milena Guedes [School of Civil Engineering, Architecture and Urbanism, University of Campinas — UNICAMP, P.O. Box 6021, CEP 13083-852, Campinas, SP (Brazil); Rath, Susanne [Chemistry Institute, University of Campinas — UNICAMP, P.O. Box 6154, CEP 13084-971, Campinas, SP (Brazil); Guimarães, José Roberto, E-mail: jorober@fec.unicamp.br [School of Civil Engineering, Architecture and Urbanism, University of Campinas — UNICAMP, P.O. Box 6021, CEP 13083-852, Campinas, SP (Brazil)

    2013-02-15

    Flumequine is a broad-spectrum antimicrobial agent of the quinolone class, and it is widely used as a veterinary drug in food-producing animals. The presence of flumequine in the environment may contribute to the development of drug resistant bacterial strains. In this study, water samples fortified with flumequine (500 μg L{sup −1}) were degraded using the Fenton and photo-Fenton processes. The maximum degradation efficiency for flumequine by the Fenton process was approximately 40% (0.5 mmol L{sup −1} Fe(II), 2.0 mmol L{sup −1} H{sub 2}O{sub 2} and 15 min). By applying UV radiation (photo-Fenton process), the efficiency reached more than 94% in 60 min when 0.25 mmol L{sup −1} Fe(II) and 10.0 mmol L{sup −1} H{sub 2}O{sub 2} were used. Under these conditions, the Fenton process was able to reduce the biological activity, whereas the photo-Fenton process eliminated almost all of the antimicrobial activity because it was not detected. Four byproducts with an m/z of 244, 238, 220 and 202 were identified by mass spectrometry, and a degradation pathway for flumequine was proposed. The byproducts were derived from decarboxylation and defluorination reactions and from modifications in the alkylamino chain of the fluoroquinolone. - Highlights: ► Photo-Fenton process achieved the maximum performance, degrading 94% of flumequine. ► As the flumequine concentration decreased, antimicrobial activity also decreased. ► Four byproducts with m/z of 244, 238, 220 and 202 were identified. ► A degradation pathway for flumequine was proposed.

  2. Detection of pyridaben residue levels in hot pepper fruit and leaves by liquid chromatography-tandem mass spectrometry: effect of household processes.

    Science.gov (United States)

    Kim, Sung-Woo; Abd El-Aty, A M; Rahman, Md Musfiqur; Choi, Jeong-Heui; Choi, Ok-Ja; Rhee, Gyu-Seek; Chang, Moon-Ik; Kim, Heejung; Abid, Morad D N; Shin, Sung Chul; Shim, Jae-Han

    2015-07-01

    Following quick, easy, cheap, effective, rugged and safe (QuEChERS) and LC/MS/MS analysis, pyridaben residual levels were determined in unprocessed and processed hot pepper fruit and leaves. The linearities were satisfactory with determination coefficients (R(2)) in excess of 0.995 in processed and unprocessed pepper fruit and leaves. Recoveries at various concentrations were 79.9-105.1% with relative standard deviations ≤15%. The limits of quantitation of 0.003-0.012 mg/kg were very low compared with the maximum residue limits (2-5 mg/kg) set by the Ministry of Food and Drug Safety, Republic of Korea. The effects of various household processes, including washing, blanching, frying and drying under different conditions (water volume, blanching time and temperature) on residual concentrations were evaluated. Both washing and blanching (in combination with high water volume and time factor) significantly reduced residue levels in hot pepper fruit and leaves compared with other processes. In sum, the developed method was satisfactory and could be used to accurately detect residues in unprocessed and processed pepper fruit and leaves. It is recommended that pepper fruit/leaves be blanched after washing before being consumed to protect consumers from the negative health effects of detected pesticide residues. Copyright © 2014 John Wiley & Sons, Ltd.

  3. The pretreatment of corn stover with Gloeophyllum trabeum KU-41 for enzymatic hydrolysis

    Directory of Open Access Journals (Sweden)

    Gao Ziqing

    2012-05-01

    Full Text Available Abstract Background Pretreatment is an essential step in the enzymatic hydrolysis of biomass for bio-ethanol production. The dominant concern in this step is how to decrease the high cost of pretreatment while achieving a high sugar yield. Fungal pretreatment of biomass was previously reported to be effective, with the advantage of having a low energy requirement and requiring no application of additional chemicals. In this work, Gloeophyllum trabeum KU-41 was chosen for corn stover pretreatment through screening with 40 strains of wood-rot fungi. The objective of the current work is to find out which characteristics of corn stover pretreated with G. trabeum KU-41 determine the pretreatment method to be successful and worthwhile to apply. This will be done by determining the lignin content, structural carbohydrate, cellulose crystallinity, initial adsorption capacity of cellulase and specific surface area of pretreated corn stover. Results The content of xylan in pretreated corn stover was decreased by 43% in comparison to the untreated corn stover. The initial cellulase adsorption capacity and the specific surface area of corn stover pretreated with G. trabeum were increased by 7.0- and 2.5-fold, respectively. Also there was little increase in the cellulose crystallinity of pretreated corn stover. Conclusion G. trabeum has an efficient degradation system, and the results indicated that the conversion of cellulose to glucose increases as the accessibility of cellulose increases due to the partial removal of xylan and the structure breakage of the cell wall. This pretreatment method can be further explored as an alternative to the thermochemical pretreatment method.

  4. Reuse of residual sludge from stone-processing: differences and similarities between sludge coming from carbonate and silicate stones

    Science.gov (United States)

    Careddu, Nicola; Antonella Dino, Giovanna

    2015-04-01

    Residual sludge coming from dimension stone working activities represents a serious environmental and economic problem both for Stone Industry and citizens. Indeed, most of time, residual sludge is landfilled because of the difficulties to recover it; such difficulties are mainly connected to local legislation and a lack of proper protocols. In general, it is possible to individuate two different categories of sludge: residual sludge coming from carbonate rocks (CS) and those coming from silicate rocks (SS). Both of them are characterised by a very fine size distribution. CS is composed mainly by the same compounds of the processed stones (marble, limestone, travertine). The reason of this is related to the very slow wear of diamond tools during processing which entails a negligible content of heavy metals. CS becomes very interesting, from an economic point of view, when it has a CaCO3 grade > 95 %. On the contrary, SS is characterised by high heavy metal and TPH content. Residual sludge from the processing of silicate rocks can be split in three different sub-categories, depending on the way they are produced, and in particular: sludge from gangsaw using abrasive steel shot (GSS), sludge from multi diamond-saw block cutter (DBC), and mixed sludge (MS) from gangsaw and block cutter. These three sub-categories show different problems connected to heavy metal content, indeed on the one hand GSS is characterised by a high percentage of Ni, Cr, Cu, etc., on the other hand DBC is characterised by Co and Cu high content. In general, sludge, management of which in Italy is administered in accordance with the Italian Legislative Decree 152/06, can be used as waste from for environmental restoration or for cement plants. Several researches investigate the possible reuse of these materials but, at present time, there is no evidence of its systematic recovery as "recycled product" or "by-product". On the basis of the results of these researches it is possible to highlight

  5. Production of edible coating based on fruit and vegetable residues: application on minimally processed carrot (Daucus carota L.

    Directory of Open Access Journals (Sweden)

    Ana Elizabeth Cavalcante Fai

    2015-03-01

    Full Text Available The application of edible coatings obtainable from alternative biodegradable materials has gained attention as a promising treatment to prolong the shelf-life of fresh-cut vegetables. Thus, this work aimed to develop a biodegradable coating based on fruit and vegetable residues flour. Immersion coating strategy was studied on the quality of minimally fresh-cut carrots during refrigeration storage by means of weight loss, color variation, pH, titratable acidity and soluble solids content. Better performance was obtained for coated carrots, which exhibited a tendency to have lower whiteness index than uncoated counterparts and enhanced overall quality. Despite a drop in color saturation expressed by chroma values (varying from 59 to 46 was observed, color index presented a positive value for all samples (varying from 13 to 15 indicating orange color preservation throughout storage. Although color parameter was influenced by coating treatment, minor modifications occur over storage concerning weight loss, pH, titratable acidity and soluble content. Results obtained demonstrated the potential of the fruit and vegetable residues flour for edible coatings formulation. Practical application on minimally processed carrots supported its suitability to be used as an alternative coating material and constitute a motivating route to evaluate and optimize this alternative preservation technique.

  6. Nutrient digestion and performance by lambs and steers fed thermochemically treated crop residues.

    Science.gov (United States)

    Sewell, J R; Berger, L L; Nash, T G; Cecava, M J; Doane, P H; Dunn, J L; Dyer, M K; Pyatt, N A

    2009-03-01

    Five studies were conducted to determine nutrient digestibility and performance of lambs and steers fed thermochemically treated crop residues and distillers dried grains with solubles (DDGS) as a corn replacement pellet (CRP; 75% residue:25% DDGS, DM basis). Fifteen Hampshire, Suffolk, or Dorset wethers (BW 33.3 +/- 5.0 kg) were utilized to evaluate nutrient digestibility of the unprocessed native (NAT) and CRP [Exp. 1: wheat straw (WS); Exp. 2: corn stover (CS); Exp. 3: switchgrass (SWG) and corn fiber:wheat chaff (CFWC)] when limit fed (Exp. 1 and 2: 1.8% of BW daily; Exp. 3: 2.5% of BW daily) compared with a 60% corn diet. In Exp. 4, 56 individually fed Dorset-cross wether lambs (BW 32.0 +/- 1.4 kg) were utilized to compare performance and digestibility of WS, wheat chaff (WC), corn fiber (CF), a 3:1 blend of corn fiber:wheat straw (CFWS), a 3:1 blend of CFWC, and SWG-CRP fed for ad libitum intake compared with a 45% corn diet. In Exp. 5, 32 individually fed Holstein steers (BW 185.2 +/- 0.9 kg) were used to evaluate performance and digestibility of diets containing corn, WS-CRP, CFWC-CRP, or NAT-WS fed for ad libitum intake. Crop residues were processed with 5% calcium oxide (DM basis) and 35% water in a double-shaft enclosed mixer (Readco Kurimoto Continuous Processor, York, PA) and subsequently pelleted with DDGS to form CRP. Feeding lambs WS-CRP (Exp. 1) or CS-CRP (Exp. 2) increased digestion of DM, NDF, and ADF compared with NAT (P crop residues are thermochemically processed. Processed crop residues may be fed in combination with DDGS to partially replace corn in ruminant diets.

  7. Metals accumulations during thermal processing of sewage sludge - characterization of bottom ash and air pollution control (APC) residues

    Science.gov (United States)

    Kasina, Monika; Kowalski, Piotr R.; Michalik, Marek

    2016-04-01

    Due to increasing mass of sewage sludge, problems in its management have appeared. Over years sewage sludge was landfilled, however due to EU directives concerning environmental issues this option is no longer possible. This type of material is considered hazardous due to highly concentrated metals and harmful elements, toxic organic substances and biological components (e.g. parasites, microbes). Currently in Europe, incineration is considered to be the most reasonable method for sewage sludge treatment. As a result of sludge incineration significant amount of energy is recovered due to high calorific value of sewage sludge but bottom ash and APC residues are being produced. In this study we show the preliminary results of chemical and mineral analyses of both bottom ash and APC residues produced in fluidized bed boiler in sewage sludge incineration plant in Poland, with a special emphasis on metals which, as a part of incombustible fraction can accumulate in the residual materials after thermal processing. The bottom ash was a SiO2-P2O5-Fe2O3-CaO-Al2O3 dominated material. Main mineral phases identified in X-ray diffraction patterns were: quartz, feldspar, hematite, and phosphates (apatite and scholzite). The bottom ash was characterized by high content of Zn - 4472 mg kg-1, Cu - 665.5 mg kg-1, Pb - 138 mg kg-1, Ni - 119.5 mg kg-1, and interestingly high content of Au - 0.858 mg kg-1 The APC residues composition was dominated by soluble phases which represent more than 90% of the material. The XRD patterns indicated thenardite, halite, anhydrite, calcite and apatite as main mineral phases. The removal of soluble phases by dissolution in deionised water caused a significant mass reduction (ca. 3% of material remained on the filters). Calcite, apatite and quartz were main identified phases. The content of metals in insoluble material is relatively high: Zn - 6326 mg kg-1, Pb - 514.3 mg kg-1, Cu - 476.6 mg kg-1, Ni - 43.3 mg kg-1. The content of Cd, As, Se and Hg was

  8. Effect of residual H2O2 from advanced oxidation processes on subsequent biological water treatment: A laboratory batch study.

    Science.gov (United States)

    Wang, Feifei; van Halem, Doris; Liu, Gang; Lekkerkerker-Teunissen, Karin; van der Hoek, Jan Peter

    2017-10-01

    H 2 O 2 residuals from advanced oxidation processes (AOPs) may have critical impacts on the microbial ecology and performance of subsequent biological treatment processes, but little is known. The objective of this study was to evaluate how H 2 O 2 residuals influence sand systems with an emphasis on dissolved organic carbon (DOC) removal, microbial activity change and bacterial community evolution. The results from laboratory batch studies showed that 0.25 mg/L H 2 O 2 lowered DOC removal by 10% while higher H 2 O 2 concentrations at 3 and 5 mg/L promoted DOC removal by 8% and 28%. A H 2 O 2 dosage of 0.25 mg/L did not impact microbial activity (as measured by ATP) while high H 2 O 2 dosages, 1, 3 and 5 mg/L, resulted in reduced microbial activity of 23%, 37% and 37% respectively. Therefore, DOC removal was promoted by the increase of H 2 O 2 dosage while microbial activity was reduced. The pyrosequencing results illustrated that bacterial communities were dominated by Proteobacteria. The presence of H 2 O 2 showed clear influence on the diversity and composition of bacterial communities, which became more diverse under 0.25 mg/L H 2 O 2 but conversely less diverse when the dosage increased to 5 mg/L H 2 O 2 . Anaerobic bacteria were found to be most sensitive to H 2 O 2 as their growth in batch reactors was limited by both 0.25 and 5 mg/L H 2 O 2 (17-88% reduction). In conclusion, special attention should be given to effects of AOPs residuals on microbial ecology before introducing AOPs as a pre-treatment to biological (sand) processes. Additionally, the guideline on the maximum allowable H 2 O 2 concentration should be properly evaluated. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  9. Processing to pure aromatics of phenosolvan extract and ''15%-residue Me'' from phenosolvan extract

    Energy Technology Data Exchange (ETDEWEB)

    Nonnenmacher, H.

    1943-08-12

    These extracts contained very large concentrations of phenolic compounds. The experiments was meant to produce from them toluene (for explosives) and other aromatics. The actual starting material was a redistillate of the extracts mentioned above. The runs were carried out in a 1,000-cubic cm DHD oven over DHD catalyst on Tonerde Lu catalyst (a form of alumina), at hydrogen partial pressures of 10 to 50 atm and temperatures from 426/sup 0/C to 527/sup 0/C, with throughputs from 0.2 to 0.5 kg/liter/hr and gas ratios from 1.0 to 2.5 cubic meters per kg of oil, and in cycles ranging from 3 1/2 hours to a week or more. Also a one-stage process was compared to a two-stage process. The experiment established that the two-stage process was successful, but still left open the question of whether the one-stage process was effective enough. The successful two-stage process consisted of (1) refining at 50 atm hydrogen pressure, 420/sup 0/C, throughput of 0.2 kg/liter/hr, and cycle time of at least a week, and then (2) dehydrogenation (of the resulting fraction boiling from 85/sup 0/C to 120/sup 0/C) at 10 atm hydrogen pressure, 510/sup 0/C, the same throughput, and cycle time of at least 16 hours. The residue Me seemed to produce more operating difficulties than the whole extract. A typical run of the two-stage process operating on 1,000 kg of phenosolvan extract yielded 139 kg pure toluene, 353 kg of a light gasoline containing about 50% aromatics by volume (and with about 90% of it boiling at up to 100/sup 0/C), 256 kg of a product boiling from 120/sup 0/ to 300/sup 0/ and having about 30% phenols and 50% aromatics, and 50 kg of distillation residue which could be used in the liquid-phase hydrogenation. The 120/sup 0/ to 300/sup 0/ product could be processed further by dehydrogenating splitting to give pure xylenes and pure toluene. 7 tables.

  10. SIMULATION OF THE FERMENTATION PROCESS TO OBTAIN BIOETHANOL FROM RICE RESIDUES

    Directory of Open Access Journals (Sweden)

    Verónica Capdevila

    2015-06-01

    Full Text Available In this paper presents a simulation model of the fermentation/separation process of bioethanol from hydrolyzed pretreated rice husk, using Aspen HYSYS simulator. Sensitivity studies performed on the developed model indicated levels for selected variables: biomass/water ratio of 1:2,89 ; biomass flow of 50 t/h and inlet temperature separator of 30°C, leading to maximize the yield of bioethanol. From these variables, a bioethanol production of 8,81 t/h with a purity of 65,51% w/w is obtained, corresponding to a flow of hydrolyzed treated biomass of 50 t/h. This work represents an advance in the development of the simulation model of the complete process to obtain second generation of bioethanol from rice husks.

  11. Non destructive evaluation of residual stresses in welding and hard-surfacing processes

    International Nuclear Information System (INIS)

    Suarez, J.C.; Fernandez, L.M.; Cruz, C.; Aragon, B.; Merino, F.

    1995-01-01

    In this paper transversal and longitudinal stress profiles in welding and hard-surfacing by welding processes are presented. The stresses were measured by RMS of Barkhausen signal. In this work it is shown that in each case the level of stresses is strongly dependent on the number of weld beads of surfacing layers deposited. The subsequent deposition of new weld beads or surfacing layers produces a stress-relieving effect

  12. Environmental sustainability assessment of fruit cultivation and processing using fruit and cocoa residues for bioenergy and compost. Case study from Ghana

    DEFF Research Database (Denmark)

    Kamp, Andreas; Østergård, Hanne

    2016-01-01

    and electricity production using farming and processing residues and by recycling of nutrients and carbon to soil. Cocoa shells are used as a co-substrate in the biogas production. Estimating the environmental impact of cocoa shell residues exposes the multifunctionality issue, continuously debated in ESA......, particularly concerning bioenergy production. We compare the use of allocation of cocoa production impacts and system expansion that includes cocoa production as possible methods to manage multifunctionality of inputs. Inassessments of residue-based production, we recommend using the latter method. Applying...

  13. Oleaginous fungal lipid fermentation on combined acid- and alkali-pretreated corn stover hydrolysate for advanced biofuel production.

    Science.gov (United States)

    Ruan, Zhenhua; Zanotti, Michael; Archer, Steven; Liao, Wei; Liu, Yan

    2014-07-01

    A combined hydrolysis process, which first mixed dilute acid- and alkali-pretreated corn stover at a 1:1 (w/w) ratio, directly followed by enzymatic saccharification without pH adjustment, has been developed in this study in order to minimize the need of neutralization, detoxification, and washing during the process of lignocellulosic biofuel production. The oleaginous fungus Mortierella isabellina was selected and applied to the combined hydrolysate as well as a synthetic medium to compare fungal lipid accumulation and biodiesel production in both shake flask and 7.5L fermentor. Fungal cultivation on combined hydrolysate exhibited comparable cell mass and lipid yield with those from synthetic medium, indicating that the integration of combined hydrolysis with oleaginous fungal lipid fermentation has great potential to improve performance of advanced lignocellulosic biofuel production. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Influence of process parameters and biomass characteristics on the durability of pellets from the pruning residues of Olea europaea L.

    Energy Technology Data Exchange (ETDEWEB)

    Carone, Maria Teresa; Pantaleo, Antonio; Pellerano, Achille [Department of Engineering and Management of the Agricultural, Livestock and Forest Systems, Faculty of Agriculture, University of Bari, Via Amendola, 165/A, 70126 Bari (Italy)

    2011-01-15

    The present work aims to investigate the influence of the main process parameters (pressure and temperature) and biomass characteristics (moisture content and particle size) on some mechanical properties (density and durability) of olive tree pruning residues pellets. By means of a lab scale pellet press, able to control process parameters, the biomass, ground with three different hammer mill screen sizes (1, 2 and 4 mm) and conditioned at different moisture contents (5, 10, 15 and 20% w.b.), was pelletized at various process temperatures (60, 90, 120 and 150 C) and pressures (71, 106, 141 and 176 MPa). Compressed sample dimensions and mass were measured in order to calculate pellet density, while compressive strength tests were carried out to estimate the durability of the final biofuel. The relationships between the factor settings and the responses (density, compression strength and modulus of elasticity) were examined by univariate and multivariate statistical analysis. Temperature resulted the most important variable influencing pellet mechanical properties, followed by the initial moisture content and the particle size of the raw material. In particular, high process temperature, low moisture contents and reduced particle sizes allowed obtaining good quality pellets. The effect of compression force resulted scarcely relevant. (author)

  15. Antimony recovery from end-of-life products and industrial process residues: A critical review

    OpenAIRE

    Dupont, David; Arnout, Sander; Jones, Peter Tom; Binnemans, Koen

    2016-01-01

    Antimony has become an increasingly critical element in recent years, due to a surge in industrial demand and the Chinese domination of primary production. Antimony is produced from stibnite ore (Sb2O3) which is processed into antimony metal and antimony oxide (Sb2O3). The industrial importance of antimony is mainly derived from its use as flame retardant in plastics, coatings, and electronics, but also as decolourizing agent in glass, alloys in lead-acid batteries, and catalysts for the p...

  16. A study on recovery of uranium in the anode basket residues delivered from the pyrochemical process of used nuclear fuel

    Science.gov (United States)

    Eun, H. C.; Kim, T. J.; Jang, J. H.; Kim, G. Y.; Park, S. B.; Yoon, D. S.; Kim, S. H.; Paek, S. W.; Lee, S. J.

    2018-04-01

    In this study, the chlorination of uranium oxide (UO2) using ammonium chloride and zirconium as chemical agents was conducted to recover the uranium in the anode basket residues from the pyrochemical process of used nuclear fuel. The chlorination of UO2 was predicted using thermodynamic equilibrium calculations. The experimental conditions for the chlorination were determined using a chlorination test with cerium oxide (CeO2). In the chlorination test, it was confirmed that UO2 was chlorinated into UCl3 at 320 °C, some UO2 remained without changes in the chemical form, and ZrO2, Zr2O, and ZrCl2 were generated as byproducts.

  17. The effect of residual chlorides on resultant properties of solid and liquid phases after carbonization process

    Energy Technology Data Exchange (ETDEWEB)

    Plevova Eva; Sugarkova Vera; Kaloc Miroslav [Institute of Geonics ASCR, Ostrava (Czech Republic). Laboratory of Petrology

    2004-07-01

    The low-concentration condition was employed to model the carbonisation mode for local (Czech Republic) coals with higher concentrations of some metals. After completing the carbonisation, mass balance calculations were performed. Results show that the presence of zinc dichloride, copper dichloride and sodium chloride caused the most pronounced impediment to the formation of tar in contrast to lead dichloride and aluminium chloride that increased tar. The results demonstrated that adding of chloride agents effect both the course of the coking process and the properties of solid and liquid products of coking. Evaluation of the solid phase showed that chloride addition caused a decrease of the caking and swelling value, which corresponds with measurements of plasticity values that are of significant influence on mechanical properties closely related to coking plant processes. Evaluation of the liquid phase pointed towards an increase of aromatic hydrocarbons and their derivatives (especially phenanthrene, fluoranthene, acenaphthylene, pyrene) but a decrease of naphthalene and methylnaphthalene. Chloride addition increased aromaticity and caused a difference in substitution rate at aromatic nucleus. Mesophase estimation indicated extensive mosaic, domain and laminated anisotropic texture occurrence after chloride addition, mainly NaCl and CuCl{sub 2} addition. A more detailed evaluation including detailed screening, TGA, IR and RTG analysis will be subject of further investigation. 4 refs., 2 figs., 5 tabs.

  18. USING THE SULFUR POLYMER STABILIZATION SOLIDIFICATION PROCESS TO TREAT RESIDUAL MERCURY WASTES FROM GOLD MINING OPERATIONS.

    Energy Technology Data Exchange (ETDEWEB)

    BOWERMAN,B.ADAMS,J.KALB,P.WAN,R.Y.LEVIER,M.

    2003-02-24

    Large quantities of mercury are generated as a by-product during the processing of gold ore following mining operations. Newmont Mining Corporation (NMC), which operates some of the world's largest gold mines, sought a method to permanently ''retire'' its mercury by-products, thereby avoiding potential environmental liability. Sulfur Polymer Stabilization-Solidification (SPSS) is an innovative technology developed at Brookhaven National Laboratory (BNL) for treatment of mercury and mercury contaminated materials, such as soil, sludge and debris. BNL conducted a treatability study to determine the potential applicability of SPSS for treatment of Newmont mercury, and the treated product passed the U.S. Environmental Protection Agency (EPA) test for toxicity. The SPSS process has been shown to be effective on radioactive and nonradioactive mercury and mercury-contaminated materials with a pilot-scale batch system capable of producing 0.03 m{sup 3} (1 ft{sup 3}) per batch. Engineering scale-up issues are discussed and material property tests addressing these issues are described.

  19. Analyzing and Comparing Biomass Feedstock Supply Systems in China: Corn Stover and Sweet Sorghum Case Studies

    Directory of Open Access Journals (Sweden)

    Lantian Ren

    2015-06-01

    Full Text Available This paper analyzes the rural Chinese biomass supply system and models supply chain operations according to U.S. concepts of logistical unit operations: harvest and collection, storage, transportation, preprocessing, and handling and queuing. In this paper, we quantify the logistics cost of corn stover and sweet sorghum in China under different scenarios. We analyze three scenarios of corn stover logistics from northeast China and three scenarios of sweet sorghum stalks logistics from Inner Mongolia in China. The case study estimates that the logistics cost of corn stover and sweet sorghum stalk to be $52.95/dry metric ton and $52.64/dry metric ton, respectively, for the current labor-based biomass logistics system. However, if the feedstock logistics operation is mechanized, the cost of corn stover and sweet sorghum stalk decreases to $36.01/dry metric ton and $35.76/dry metric ton, respectively. The study also includes a sensitivity analysis to identify the cost factors that cause logistics cost variation. Results of the sensitivity analysis show that labor price has the most influence on the logistics cost of corn stover and sweet sorghum stalk, with a variation of $6 to $12/dry metric ton.

  20. UOE Pipe Numerical Model: Manufacturing Process And Von Mises Residual Stresses Resulted After Each Technological Step

    Science.gov (United States)

    Delistoian, Dmitri; Chirchor, Mihael

    2017-12-01

    Fluid transportation from production areas to final customer is effectuated by pipelines. For oil and gas industry, pipeline safety and reliability represents a priority. From this reason, pipe quality guarantee directly influence pipeline designed life, but first of all protects environment. A significant number of longitudinally welded pipes, for onshore/offshore pipelines, are manufactured by UOE method. This method is based on cold forming. In present study, using finite element method is modeled UOE pipe manufacturing process and is obtained von Mises stresses for each step. Numerical simulation is performed for L415 MB (X60) steel plate with 7,9 mm thickness, length 30 mm and width 1250mm, as result it is obtained a DN 400 pipe.

  1. Analysis and Modeling of Process of Residual Deformations Accumulation in Soils and Granular Materials

    Science.gov (United States)

    Aleksandrov, A. S.; Dolgih, G. V.; Kalinin, A. L.

    2017-11-01

    It is established that under the influence of repeated loads the process of plastic deformation in soils and discrete materials is hereditary. To perform the mathematical modeling of plastic deformation, the authors applied the integral equation by solution of which they manage to obtain the power and logarithmic dependencies connecting plastic deformation with the number of repeated loads, the parameters of the material and components of the stress tensor in the principal axes. It is shown that these dependences generalize a number of models proposed earlier in Russia and abroad. Based on the analysis of the experimental data obtained during material testing in the dynamic devices of triaxial compression at different values of the stress deviator, the coefficients in the proposed models of deformation are determined. The authors determined the application domain for logarithmic and degree dependences.

  2. Bio-energy in the wood processing industry. Manual for energy production from residual matter for the wood processing industry

    International Nuclear Information System (INIS)

    Van Halen, C.J.G.; Arninkhof, M.J.C.; Rommens, P.J.M.; Karsch, P.

    2000-04-01

    This manual is published within the framework of a project, financed by Novem (EWAB programme) and the European Commission (Altener programme). Similar manuals were drafted in Germany, England and Sweden. The basis of the project was the manual 'Quality manual for small-scale wood incineration and wood gasification', published by Novem in 1998. That quality manual was drafted on the basis of an evaluation of a number of wood combustion and wood gasification projects. The original manual has been improved as a result of comments made by experts in the field of bio-energy. Updated information was added with respect to legislation, financing options and new technology. Also the manual is focused more on the wood processing industry

  3. PRODUCTION OF PASSION FRUIT SEEDLINGS WITH THE RESIDUE OF AGROINDUSTRIAL PROCESSING OF POTATOES AS A STRATEGY IN THE SUSTAINABILITY OF AGRICULTURAL FAMILY ACTIVITY

    Directory of Open Access Journals (Sweden)

    Leonardo Humberto Silva e Castro

    2012-12-01

    Full Text Available In order to contribute to family farming sustainable development and to the environmental management of the residue generated from potato processing by the company "Bem Brasil Alimentos LTDA" from Araxa, Minas Gerais, Brazil, an experiment was conducted at the Experimental Farm of Araxa (FEAX - EPAMIG between February to April of 2012, aiming to analyze passion fruit seedlings development from the use of different doses of this residue such as substrate, to reduce costs of raw materials. The experiment was conducted in randomized block design with six treatments, four repetitions and 20 plants per plot, being the treatments, blends of soil (latosol with levels of 10%, 20% and 30% of potato processing residue associated to chemical treatment and a witness. After 70 days of sowing, the height of air part (cm, root length (cm, number of leaves and total dry matter (g were evaluated. The best treatment was the M4 which used latosol + chemical treatment + 20% of residue. It was diagnosed that the use of agroindustrial potato processing residue, as part of the substrate, is a favorable alternative for passion fruit seedlings development. Thus, it gives a destination to this residue instead of discarding it into the environment, as well as decreases the costs of raw material that permit its correct ecological use, besides generating more income for family farmers.

  4. Polymorphisms in O-methyltransferase genes are associated with stover cell wall digestibility in European maize (Zea mays L.)

    DEFF Research Database (Denmark)

    Brenner, Everton A; Zein, Imad; Chen, Yongsheng

    2010-01-01

    Background OMT (O-methyltransferase) genes are involved in lignin biosynthesis, which relates to stover cell wall digestibility. Reduced lignin content is an important determinant of both forage quality and ethanol conversion efficiency of maize stover. Results Variation in genomic sequences coding...

  5. Characterisation of non-degraded oligosaccharides in enzymatically hydrolysed and fermented, dilute ammonia-pretreated corn stover for ethanol production

    NARCIS (Netherlands)

    Jonathan, M.C.; DeMartini, J.; Stigt Thans, Van S.; Hommes, R.; Kabel, M.A.

    2017-01-01

    Background: Corn stover is lignocellulosic biomass that has potential to be used as raw material for bioethanol production. In the current research, dilute ammonia pretreatment was used to improve the accessibility of corn stover carbohydrates to subsequently added hydrolytic enzymes. Some

  6. Fuel ethanol production from wet oxidised corn stover by S. cerevisiae

    DEFF Research Database (Denmark)

    Qiang, zhang; Thomsen, Anne Belinda

    2012-01-01

    of 74.6% were obtained after pretreatment. 86.5% of cellulose was remained in the solid cake. After 24h hydrolysis at 50°C using cellulase (Cellubrix L), the achieved conversion of cellulose to glucose was 64.8%. Ethanol production was evaluated from dried solid cake and the hydrolysate was employed......In order to find out appropriate process for ethanol production from corn stover, wet oxidation (195°C, 15 minutes) and simultaneous saccharification and fermentation (SSF) was carried out to produce ethanol. The results showed that the cellulose recovery of 92.9% and the hemicellulose recovery...... as liquid fraction. After 142 h of SSF with substrate concentration of 8% (W/V), ethanol yield of 73.1 % of the theoretical based on glucose in the raw material was obtained by S. cerevisiae(ordinary baker' yeast). The corresponding ethanol concentration and volumetric productivity were 17.2g/L and 0.121g...

  7. Parametric study for the optimization of ionic liquid pretreatment of corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Papa, Gabriella [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Feldman, Taya [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Sandia National Lab. (SNL-CA), Livermore, CA (United States); Sale, Kenneth L. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Sandia National Lab. (SNL-CA), Livermore, CA (United States); Adani, Fabrizio [Univ. degli Studi di Milano (Italy); Singh, Seema [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Sandia National Lab. (SNL-CA), Livermore, CA (United States); Simmons, Blake A. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-05-30

    A parametric study of the efficacy of the ionic liquid (IL) pretreatment (PT) of corn stover (CS) using 1-ethyl-3-methylimidazolium acetate ([C2C1Im][OAc] ) and cholinium lysinate ([Ch][Lys] ) was conducted. The impact of 50% and 15% biomass loading for milled and non-milled CS on IL-PT was evaluated, as well the impact of 20 and 5 mg enzyme/g glucan on saccharification efficiency. The glucose and xylose released were generated from 32 conditions – 2 ionic liquids (ILs), 2 temperatures, 2 particle sizes (S), 2 solid loadings, and 2 enzyme loadings. Statistical analysis indicates that sugar yields were correlated with lignin and xylan removal and depends on the factors, where S did not explain variation in sugar yields. Both ILs were effective in pretreating large particle sized CS, without compromising sugar yields. The knowledge from material and energy balances is an essential step in directing optimization of sugar recovery at desirable process conditions.

  8. Parametric study for the optimization of ionic liquid pretreatment of corn stover.

    Science.gov (United States)

    Papa, Gabriella; Feldman, Taya; Sale, Kenneth L; Adani, Fabrizio; Singh, Seema; Simmons, Blake A

    2017-10-01

    A parametric study of the efficacy of the ionic liquid (IL) pretreatment (PT) of corn stover (CS) using 1-ethyl-3-methylimidazolium acetate ([C 2 C 1 Im][OAc]) and cholinium lysinate ([Ch][Lys]) was conducted. The impact of 50% and 15% biomass loading for milled and non-milled CS on IL-PT was evaluated, as well the impact of 20 and 5mg enzyme/g glucan on saccharification efficiency. The glucose and xylose released were generated from 32 conditions - 2 ionic liquids (ILs), 2 temperatures, 2 particle sizes (S), 2 solid loadings, and 2 enzyme loadings. Statistical analysis indicates that sugar yields were correlated with lignin and xylan removal and depends on the factors, where S did not explain variation in sugar yields. Both ILs were effective in pretreating large particle sized CS, without compromising sugar yields. The knowledge from material and energy balances is an essential step in directing optimization of sugar recovery at desirable process conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Analysis of supply chain, scale factor, and optimum plant capacity for the production of ethanol from corn stover

    International Nuclear Information System (INIS)

    Leboreiro, Jose; Hilaly, Ahmad K.

    2013-01-01

    A detailed model is used to perform a thorough analysis on ethanol production from corn stover via the dilute acid process. The biomass supply chain cost model accounts for all steps needed to source corn stover including collection, transportation, and storage. The manufacturing cost model is based on work done at NREL; attainable conversions of key process parameters are used to calculate production cost. The choice of capital investment scaling function and scaling parameter has a significant impact on the optimum plant capacity. For the widely used exponential function, the scaling factors are functions of plant capacity. The pre-exponential factor decreases with increasing plant capacity while the exponential factor increases as the plant capacity increases. The use of scaling parameters calculated for small plant capacities leads to falsely large optimum plants; data from a wide range of plant capacities is required to produce accurate results. A mathematical expression to scale capital investment for fermentation-based biorefineries is proposed which accounts for the linear scaling behavior of bio-reactors (such as saccharification vessels and fermentors) as well as the exponential nature of all other plant equipment. Ignoring the linear scaling behavior of bio-reactors leads to artificially large optimum plant capacities. The minimum production cost is found to be in the range of 789–830 $ m −3 which is significantly higher than previously reported. Optimum plant capacities are in the range of 5750–9850 Mg d −1 . The optimum plant capacity and production cost are highly sensitive to farmer participation in biomass harvest for low participation rates. -- Highlights: •A detailed model is used to perform a technoeconomic analysis for the production of ethanol from corn stover. •The capital investment scaling factors were found to be a function of plant capacity. •Bio-reactors (such as saccharification vessels and fermentors) in large size

  10. Modeling the CO2 and N2O Emissions From Stover Removal for Biofuel Production From Continuous Corn Production in Iowa

    Science.gov (United States)

    Paustian, K.; Killian, K.; Brenner, J.

    2003-12-01

    Corn stover, an agricultural residue, can be used as feedstock for near term bioethanol production and is available today at levels that can significantly impact energy supply. We evaluated the environmental impact of such a large-scale change in agricultural practices on green house gas production, soil erosion and soil carbon using the Century model. Estimates of soil C changes and GHG emissions were performed for the 99 counties in Iowa where previous environmental, management and erosion data was available. We employed climate, soil and historical management databases from a separate USDA-funded project as input to Century. RUSLE estimates of the residue requirements for acceptable soil loss rates under continuous corn agriculture were available from a previous study done Dr. Richard Nelson (Enersol Resources). Two mulch tillage and a no-till systems, where erosion estimates were available, were used as the basis for the simulations. Century simulations of these systems were run under a variety of stover removal rates. For each soil type within each county the model was run for 15 years (1980-1995) under continuous corn with convention tillage, and full residue return. Model simulation of crop yields and residue production were then calibrated to match those used by the Polysys model team at Oak Ridge and the simulation was repeated with the addition of the three corn tillage regimes, and several residue removal rates. County-average soil C changes (and net CO2 emissions) were calculated as area-weighted averages of the individual soil types in each county. For this study, we have utilized the IPCC approach to estimate annual N2O emissions. At low or zero residue removal rates, county-averaged soil C stocks were predicted to increase (i.e. net CO2 emissions are negative). Where the allowable residue removal rates (based on erosion tolerance) for mulch-tillage are on the order of 40-50% or more, the reduced input of C is such that the soils no longer sequester C

  11. Effect of process variables on the Drucker-Prager cap model and residual stress distribution of tablets estimated by the finite element method.

    Science.gov (United States)

    Hayashi, Yoshihiro; Otoguro, Saori; Miura, Takahiro; Onuki, Yoshinori; Obata, Yasuko; Takayama, Kozo

    2014-01-01

    A multivariate statistical technique was applied to clarify the causal correlation between variables in the manufacturing process and the residual stress distribution of tablets. Theophylline tablets were prepared according to a Box-Behnken design using the wet granulation method. Water amounts (X1), kneading time (X2), lubricant-mixing time (X3), and compression force (X4) were selected as design variables. The Drucker-Prager cap (DPC) model was selected as the method for modeling the mechanical behavior of pharmaceutical powders. Simulation parameters, such as Young's modulus, Poisson rate, internal friction angle, plastic deformation parameters, and initial density of the powder, were measured. Multiple regression analysis demonstrated that the simulation parameters were significantly affected by process variables. The constructed DPC models were fed into the analysis using the finite element method (FEM), and the mechanical behavior of pharmaceutical powders during the tableting process was analyzed using the FEM. The results of this analysis revealed that the residual stress distribution of tablets increased with increasing X4. Moreover, an interaction between X2 and X3 also had an effect on shear and the x-axial residual stress of tablets. Bayesian network analysis revealed causal relationships between the process variables, simulation parameters, residual stress distribution, and pharmaceutical responses of tablets. These results demonstrated the potential of the FEM as a tool to help improve our understanding of the residual stress of tablets and to optimize process variables, which not only affect tablet characteristics, but also are risks of causing tableting problems.

  12. Stainless steels with low contents in residual elements for nitric acid environments. Influence of melting processes

    International Nuclear Information System (INIS)

    Desestret, A.; Gay, G.; Soulignac, P.

    1983-01-01

    Nitric acid solutions, as they are for instance employed in the chemical treatment of nuclear fuels, do not apparently pose any more corrosion problems and the safe use of the several steels is well documented. The most difficult corrosion problems are next those related to ''tunnel'' penetrations, in the hot-rolling direction (longitudinal). This phenomenon can be quite important such as to imperial complex structures. Up to the last few years, the only manner to eliminate such ''tunnel'' corrosions was to carry out special operations of remelting and refining under careful selected slag (Electro Slag Remelting or ESR). It turns out indeed that non metallic inclusions are the prime factors in this type of corrosion. Well adapted ladle refining processes made possible to obtain equivalent results at lower costs, while purity and cleanliness are improved to such a degree that a steel of type Cr 18 - Ni 10 thus produced exhibit a nearly absolute resistance to intergranular corrosion in the 14 N (65%) boiling nitric acid (the Huey test) whatever the ''sensitization'' treatment, between 1000 0 C and 600 0 C. In view of its very high tolerance to varied thermal cycles and of the near complete disappearance of any ''tunnel'' corrosion, such a steel is of great interest when complex parts are produced, by machining forged or rolled metal, which is then assembled by welding techniques or procedures which would be forbidden in the case of usual Cr 18 -Ni 10 steels. Similar improvements are also obtained on the two other special steels used in nitric environments: Cr 25 - Ni 20 - C [fr

  13. Impact of Sequential Ammonia Fiber Expansion (AFEX) Pretreatment and Pelletization on the Moisture Sorption Properties of Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Bonner, Ian J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Thompson, David N. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Teymouri, Farzaneh [Michigan Biotechnology Inst., Lansing, MI (United States); Campbell, Timothy [Michigan Biotechnology Inst., Lansing, MI (United States); Bals, Bryan [Michigan Biotechnology Inst., Lansing, MI (United States); Tumuluru, Jaya Shankar [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-05-01

    Combining ammonia fiber expansion (AFEX™) pretreatment with a depot processing facility is a promising option for delivering high-value densified biomass to the emerging bioenergy industry. However, because the pretreatment process results in a high moisture material unsuitable for pelleting or storage (40% wet basis), the biomass must be immediately dried. If AFEX pretreatment results in a material that is difficult to dry, the economics of this already costly operation would be at risk. This work tests the nature of moisture sorption isotherms and thin-layer drying behavior of corn (Zea mays L.) stover at 20°C to 60°C before and after sequential AFEX pretreatment and pelletization to determine whether any negative impacts to material drying or storage may result from the AFEX process. The equilibrium moisture content to equilibrium relative humidity relationship for each of the materials was determined using dynamic vapor sorption isotherms and modeled with modified Chung-Pfost, modified Halsey, and modified Henderson temperature-dependent models as well as the Double Log Polynomial (DLP), Peleg, and Guggenheim Anderson de Boer (GAB) temperature-independent models. Drying kinetics were quantified under thin-layer laboratory testing and modeled using the Modified Page's equation. Water activity isotherms for non-pelleted biomass were best modeled with the Peleg temperature-independent equation while isotherms for the pelleted biomass were best modeled with the Double Log Polynomial equation. Thin-layer drying results were accurately modeled with the Modified Page's equation. The results of this work indicate that AFEX pretreatment results in drying properties more favorable than or equal to that of raw corn stover, and pellets of superior physical stability in storage.

  14. High solid simultaneous saccharification and fermentation of wet oxidized corn stover to ethanol

    DEFF Research Database (Denmark)

    Varga, E.; Klinke, H.B.; Reczey, K.

    2004-01-01

    In this study ethanol was produced from corn stover pretreated by alkaline and acidic wet oxidation (WO) (195 degreesC, 15 min, 12 bar oxygen) followed by nonisothermal simultaneous saccharification and fermentation (SSF). In the first step of the SSF, small amounts of cellulases were added at 50....../L) were present in the hemicellulose rich hydrolyzate at subinhibitory levels, thus no detoxification was needed prior to SSF of the whole slurry. Based on the cellulose available in the WO corn stover 83% of the theoretical ethanol yield was obtained under optimized SSF conditions. This was achieved...... with a substrate concentration of 12% dry matter (DM) acidic WO corn stover at 30 FPU/g DM (43.5 FPU/g cellulose) enzyme loading. Even with 20 and 15 FPU/g DM (corresponding to 29 and 22 FPU/g cellulose) enzyme loading, ethanol yields of 76 and 73%, respectively, were obtained. After 120 h of SSF the highest...

  15. Enzymatic hydrolysis of pelletized AFEX™-treated corn stover at high solid loadings.

    Science.gov (United States)

    Bals, Bryan D; Gunawan, Christa; Moore, Janette; Teymouri, Farzaneh; Dale, Bruce E

    2014-02-01

    Ammonia fiber expansion (AFEX™) pretreatment can be performed at small depots, and the pretreated biomass can then be pelletized and shipped to a centralized refinery. To determine the feasibility of this approach, pelletized AFEX-treated corn stover was hydrolyzed at high (18-36%) solid loadings. Water absorption and retention by the pellets was low compared to unpelletized stover, which allowed enzymatic hydrolysis slurries to remain well mixed without the need for fed-batch addition. Glucose yields of 68% and xylose yields of 65% were obtained with 20 mg enzyme/g glucan and 18% solid loading after 72 h, compared to 61% and 59% for unpelletized corn stover. Pelletization also slightly increased the initial rate of hydrolysis compared to unpelletized biomass. The ease of mixing and high yields obtained suggests that pelletization after AFEX pretreatment could have additional advantages beyond improved logistical handling of biomass. © 2013 Wiley Periodicals, Inc.

  16. Improvement of corn stover bioconversion efficiency by using plant glycoside hydrolase.

    Science.gov (United States)

    Han, Yejun; Chen, Hongzhang

    2011-04-01

    Plant cell wall is the most abundant substrate for bioethanol production, and plants also represent a key resource for glycoside hydrolase (GH). To exploit efficient way for bioethanol production with lower cellulase loading, the potential of plant GH for lignocellulose bioconversion was evaluated. The GH activity for cell wall proteins (CWPs) was detected from fresh corn stover (FCS), and the synergism of which with Trichoderma reesei cellulase was also observed. The properties for the GH of FCS make it a promising enzyme additive for lignocellulose biodegradation. To make use of the plant GH, novel technology for hydrolysis and ethanol fermentation was developed with corn stover as substrate. Taking steam-exploded corn stover as substrate for hydrolysis and ethanol fermentation, compared with T. reesei cellulase loaded alone, the final glucose and ethanol accumulation increased by 60% and 63% respectively with GH of FCS as an addition. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. The Eyring-Stover theory of survival applied to life-span radiation effects studies in animals

    International Nuclear Information System (INIS)

    Stover, B.J.; Wrenn, M.E.; Jee, W.S.S.; Atherton, D.R.

    1986-01-01

    The Eyring-Stover theory of survival describes the observed biological phenomena of damage and repair as steady-state processes that can be expressed in the formalism of absolute reaction rate theory. The steady-state formulation, rather than that of dynamic equilibrium, is invoked since biological phenomena, in contrast with most chemical and physical phenemena, are time irreversible. The theory is appropriate for calculating life shortening that results from environmental factors such as irradiation since it does not require universality and intrinsicality as to some theories of aging. The theory gives not only midrange mortality rate values but also end-range values, which are difficult to predict empirically. The previously calculated life shortening of mice after external x-irradiation and of beagles after internal irradiation from 239 Pu or 226 Ra is reviewed; life shortening at low dose levels of 226 Ra is presented. 21 refs., 1 tab

  18. Highly efficient production of optically pure l-lactic acid from corn stover hydrolysate by thermophilic Bacillus coagulans.

    Science.gov (United States)

    Ma, Kedong; Hu, Guoquan; Pan, Liwei; Wang, Zichao; Zhou, Yi; Wang, Yanwei; Ruan, Zhiyong; He, Mingxiong

    2016-11-01

    A thermophilic strain Bacillus coagulans (NBRC 12714) was employed to produce l-lactic acid from corn stover hydrolysate in membrane integrated continuous fermentation. The strain NBRC 12714 metabolized glucose and xylose by the Embden-Meyerhof-Parnas pathway (EMP) and the pentose phosphate pathway (PPP), producing l-lactic acid with optical purity >99.5%. The overall l-lactic acid titer of 92g/l with a yield of 0.91g/g and a productivity of 13.8g/l/h were achieved at a dilution rate of 0.15h(-1). The productivity obtained was 1.6-fold than that of conventional continuous fermentation without cell recycling, and also was the highest among the relevant studies ever reported. These results indicated that the process developed had great potential for economical industrial production of l-lactic acid from lignocellulosic biomass. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. [Study on determination of anthraquinones in dachengqi tang residues of Magnolia officinalis and Citrus aurantium removed in decoction process].

    Science.gov (United States)

    Wang, Yue-Sheng; Deng, Jie-Hua; Wei, Hui-Zhen; Rao, Yi; Shen, Feng-Yun; Jin, Hao-Xin

    2013-03-01

    The traditional decoction method of Dachengqi Tang is that "First boiling Magnolia officinalis and Citrus aurantium with a pipeful of water, taking out five litres from the decoction, removing residues, adding rheum officinale, boiling again, taking out two litres from it, removing residues, adding mirabilite, boiling it with low fire". According to it, residues of M. officinalis and C. aurantium should be removed after decocting. This essay aims to study the content of anthraquinones, in order to proof whether the removal of residues of M. officinalis and C. aurantium is scientific. The traditional method was adopted to prepare Dachengqi Tang. Decoction A (original method) was obtained by removing residues of M. officinalis and C. aurantium, whereas decoction B was obtained without removing residues of M. officinalis and C. aurantium. The content of anthraquinones of both methods was determined with HPLC. The content of both combined and free anthraquinones in decoction A was higher than that of decoction B. The content of total anthraquinones in residues of decoction A was lower than that of residue B. The traditional decoction method of removing residues of M. officinalis and C. aurantium from Dachengqi Tang is scientific, because it improves the dissolution rate of effective ingredients, which provides a theoretical basis for effective substances of the drug.

  20. Soil nutrient budgets following projected corn stover harvest for biofuel production in the conterminous United States

    Science.gov (United States)

    Tan, Zhengxi; Liu, Shuguang

    2015-01-01

    Increasing demand for food and biofuel feedstocks may substantially affect soil nutrient budgets, especially in the United States where there is great potential for corn (Zea mays L) stover as a biofuel feedstock. This study was designed to evaluate impacts of projected stover harvest scenarios on budgets of soil nitrogen (N), phosphorus (P), and potassium (K) currently and in the future across the conterminous United States. The required and removed N, P, and K amounts under each scenario were estimated on the basis of both their average contents in grain and stover and from an empirical model. Our analyses indicate a small depletion of soil N (−4 ± 35 kg ha−1) and K (−6 ± 36 kg ha−1) and a moderate surplus of P (37 ± 21 kg ha−1) currently on the national average, but with a noticeable variation from state to state. After harvesting both grain and projected stover, the deficits of soil N, P, and K were estimated at 114–127, 26–27, and 36–53 kg ha−1 yr−1, respectively, in 2006–2010; 131–173, 29–32, and 41–96 kg ha−1 yr−1, respectively, in 2020; and 161–207, 35–39, and 51–111 kg ha−1 yr−1, respectively, in 2050. This study indicates that the harvestable stover amount derived from the minimum stover requirement for maintaining soil organic carbon level scenarios under current fertilization rates can be sustainable for soil nutrient supply and corn production at present, but the deficit of P and K at the national scale would become larger in the future.

  1. Dissipation kinetics, safety evaluation, and assessment of pre-harvest interval (PHI) and processing factor for kresoxim methyl residues in grape.

    Science.gov (United States)

    Sabale, Rupali; Shabeer, T P Ahammed; Utture, Sagar C; Banerjee, Kaushik; Jadhav, Manjusha R; Oulkar, Dasharath P; Adsule, Pandurang G; Deshmukh, Madhukar B

    2014-04-01

    A field dissipation study was conducted to evaluate the pre-harvest interval (PHI) and processing factor (PF) for kresoxim methyl (Ergon 44.3 SC) residues in grapes and during raisin making process at recommended dose (RD) and double the recommended dose (DRD). Kresoxim methyl residues dissipated following 1st-order kinetics with a half-life of 10 and 18 days at RD and DRD, respectively. The PHIs with respect to the European Union maximum residue limit (EU-MRL) of 1 mg kg(-1) for grapes were 13 and 30 days at RD and DRD, respectively. The degradation data during grape to raisin making process were best fitted to nonlinear 1st + 1st-order kinetics with a half-life ranging between 4 and 8 days for both shade drying and with raisin dryer at different doses. The PFs were 1.19 and 1.24 with shade drying and 1.09 and 1.10 with raisin dryer, respectively, which indicates concentration of the residues during raisin making process. The dietary exposure of kresoxim methyl on each sampling day was less than the respective maximum permissible intake both at RD and DRD. The residues of kresoxim methyl in market samples of grapes and raisins were well below the EU-MRL and were also devoid of any risk of acute toxicity related to dietary exposure.

  2. Highly conserved serine residue 40 in HIV-1 p6 regulates capsid processing and virus core assembly

    Directory of Open Access Journals (Sweden)

    Solbak Sara MØ

    2011-02-01

    Full Text Available Abstract Background The HIV-1 p6 Gag protein regulates the final abscission step of nascent virions from the cell membrane by the action of two late assembly (L- domains. Although p6 is located within one of the most polymorphic regions of the HIV-1 gag gene, the 52 amino acid peptide binds at least to two cellular budding factors (Tsg101 and ALIX, is a substrate for phosphorylation, ubiquitination, and sumoylation, and mediates the incorporation of the HIV-1 accessory protein Vpr into viral particles. As expected, known functional domains mostly overlap with several conserved residues in p6. In this study, we investigated the importance of the highly conserved serine residue at position 40, which until now has not been assigned to any known function of p6. Results Consistently with previous data, we found that mutation of Ser-40 has no effect on ALIX mediated rescue of HIV-1 L-domain mutants. However, the only feasible S40F mutation that preserves the overlapping pol open reading frame (ORF reduces virus replication in T-cell lines and in human lymphocyte tissue cultivated ex vivo. Most intriguingly, L-domain mediated virus release is not dependent on the integrity of Ser-40. However, the S40F mutation significantly reduces the specific infectivity of released virions. Further, it was observed that mutation of Ser-40 selectively interferes with the cleavage between capsid (CA and the spacer peptide SP1 in Gag, without affecting cleavage of other Gag products. This deficiency in processing of CA, in consequence, led to an irregular morphology of the virus core and the formation of an electron dense extra core structure. Moreover, the defects induced by the S40F mutation in p6 can be rescued by the A1V mutation in SP1 that generally enhances processing of the CA-SP1 cleavage site. Conclusions Overall, these data support a so far unrecognized function of p6 mediated by Ser-40 that occurs independently of the L-domain function, but selectively

  3. Design of a process for the use of residual hydrocarbons coming from the ships arriving at Moin for obtaining of a fuel

    International Nuclear Information System (INIS)

    Madrigal Calderon, Adolfo

    2015-01-01

    A process is designed to carry out the obtaining of a fuel from the residual mixture of residual oils coming from the ships arriving at Moin, Limon, Costa Rica . A sampling of the residual oil in different ships is realized for a month to quantify the water content and basic sediment, as well as the heavy metal content. The results obtained have been 20,4 ± 4,6 % v/v of water and sediment, and 6,939 ppm of heavy metals as a minimum, this value may be higher depending on the quality of lubricant. The production volume of the residual oil is estimated according to historical data of the company ACASE S.A. (company responsible for collecting the oil residue of ships arriving at dock of Moin, Limon); therefore, the plant must process 25,000 liters of dirty oil per day. The main technologies (thermal process, treatment with chemical reaction, vacuum distillation and solvent extraction) to perform the process are compared and studied through a selection matrix. The technical and economic parameters chosen for the matrix have been: environmental impact, cost of operation, cost of equipment, safety of operation, maintenance of equipment, by-products obtained, waste generated, quality of the product obtained and ease of operation. The study has concluded that the treatment with chemical reaction has been the best option for the project of used oil utilization, as well as other physical methods of cleaning as the centrifugation of the same one. The installation of a waste oil processing plant has been a project that environmentally represents a benefit and economically viable, as currently the residual oil is left untreated for later use [es

  4. Cellulosic Biomass Sugars to Advantage Jet Fuel: Catalytic Conversion of Corn Stover to Energy Dense, Low Freeze Point Paraffins and Naphthenes: Cooperative Research and Development Final Report, CRADA Number CRD-12-462

    Energy Technology Data Exchange (ETDEWEB)

    Elander, Rick [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-08-04

    NREL will provide scientific and engineering support to Virent Energy Systems in three technical areas: Process Development/Biomass Deconstruction; Catalyst Fundamentals; and Technoeconomic Analysis. The overarching objective of this project is to develop the first fully integrated process that can convert a lignocellulosic feedstock (e.g., corn stover) efficiently and cost effectively to a mix of hydrocarbons ideally suited for blending into jet fuel. The proposed project will investigate the integration of Virent Energy System’s novel aqueous phase reforming (APR) catalytic conversion technology (BioForming®) with deconstruction technologies being investigated by NREL at the 1-500L scale. Corn stover was chosen as a representative large volume, sustainable feedstock.

  5. Degradation of nitroaromatic compounds and remediation of residues from the explosive production by reductive-oxidative processes based on zero-valent iron

    OpenAIRE

    Cavalotti, Luiz Fernando Rocha; Peralta-Zamora, Patricio; Rodrigues, Marcio Barreto; Paiva, Teresa Cristina Brazil de

    2009-01-01

    In this work the potentiality of reductive-oxidative processes based on zero-valent iron was studied aiming the degradation of nitroaromatic compounds and the remediation of residues from the explosive industry. The reductive process was applied as a continuous treatment system, using steel-wool as zero-valent iron source. The process permitted an almost total degradation of nitrobenzene, nitrophenol, nitrotoluene, dinitrotoluene and trinitrotoluene, probably with generation of the respective...

  6. Metabolism and Residues of 2,4-Dichlorophenoxyacetic Acid in DAS-40278-9 Maize (Zea mays) Transformed with Aryloxyalkanoate Dioxygenase-1 Gene.

    Science.gov (United States)

    Zhou, Xiao; Rotondaro, Sandra L; Ma, Mingming; Rosser, Steve W; Olberding, Ed L; Wendelburg, Brian M; Adelfinskaya, Yelena A; Balcer, Jesse L; Blewett, T Craig; Clements, Bruce

    2016-10-12

    DAS-40278-9 maize, which is developed by Dow AgroSciences, has been genetically modified to express the aryloxyalkanoate dioxygenase-1 (AAD-1) protein and is tolerant to phenoxy auxin herbicides, such as 2,4-dichlorophenoxyacetic acid (2,4-D). To understand the metabolic route and residue distribution of 2,4-D in DAS-40278-9 maize, a metabolism study was conducted with 14 C-radiolabeled 2,4-D applied at the maximum seasonal rate. Plants were grown in boxes outdoors. Forage and mature grain, cobs, and stover were collected for analysis. The metabolism study showed that 2,4-D was metabolized to 2,4-dichlorophenol (2,4-DCP), which was then rapidly conjugated with glucose. Field-scale residue studies with 2,4-D applied at the maximum seasonal rate were conducted at 25 sites in the U.S. and Canada to measure the residues of 2,4-D and free and conjugated 2,4-DCP in mature forage, grain, and stover. Residues of 2,4-D were not detectable in the majority of the grain samples and averaged <1.0 and <1.5 μg/g in forage and stover, respectively. Free plus conjugated 2,4-DCP was not observed in grain and averaged <1.0 μg/g in forage and stover.

  7. Use of residues proceeding from marbles and granites finishing and manufacturing processes as raw material for structural ceramic

    International Nuclear Information System (INIS)

    Mello, Roberta Monteiro de

    2006-01-01

    In order to decrease environmental impact, caused by mud discarding and clay extraction in the ceramic industry, it was used residual mud from marble and granite companies for structural ceramic. Samples were collected in twelve different marble companies located at the metropolitan region of Sao Paulo. However, only four samples were selected, based on its different characteristics. Clay stone was the raw material chosen to prepare the structural ceramic, considering its high use in this segment. Samples and clay stone were both analysed by the following procedures: granulometric analysis, x-rays fluorescent chemical analysis and x-rays diffraction mineralogical analysis, besides, tests in the samples were conducted following NBR 10004 standards. Once raw materials were characterized, the plasticity test was conducted. Test specimen were molded with different levels of mud, then burned and submitted to technological tests, such as: mechanical resistance, water absorption, porosity, specific gravity and retraction, material dilation before burning process and scanning electron microscopy. The final results have shown the viability of using this kind of mud, and pointed some advantages on its usage, but taking in consideration some previous conditions to be adopted. (author)

  8. Residual radioactivity investigation and radiological assessments for self-disposal of concrete waste in nuclear fuel processing facility

    International Nuclear Information System (INIS)

    Seol, Jeung Gun; Ryu, Jae Bong; Cho, Suk Ju; Yoo, Sung Hyun; Song, Jung Ho; Baek, Hoon; Kim, Seong Hwan; Shin, Jin Seong; Park, Hyun Kyoun

    2007-01-01

    In this study, domestic regulatory requirement was investigated for self-disposal of concrete waste from nuclear fuel processing facility. And after self-disposal as landfill or recycling/reuse, the exposure dose was evaluated by RESRAD Ver. 6.3 and RESRAD BUILD Ver. 3.3 computing code for radiological assessments of the general public. Derived clearance level by the result of assessments for the exposure dose of the general public is 0.1071Bq/g (3.5% enriched uranium) for landfill and 0.05515 Bq/cm 2 (5% enriched uranium) for recycling/reuse respectively. Also, residual radioactivity of concrete waste after decontamination was investigated in this study. The result of surface activity is 0.01Bq/cm 2 for emitter and the result of radionuclide analysis for taken concrete samples from surface of concrete waste is 0.0297Bq/g for concentration of 238 U, below 2w/o for enrichment of 235 U and 0.0089Bq/g for artificial contamination of 238 U respectively. Therefore, radiological hazard of concrete waste by self-disposal as landfill and recycling/reuse is below clearance level to comply with clearance criterion provided for Notice No. 2001-30 of the MOST and Korea Atomic Energy Act

  9. Understanding the Impacts of AFEX™ Pretreatment and Densification on the Fast Pyrolysis of Corn Stover, Prairie Cord Grass, and Switchgrass.

    Science.gov (United States)

    Sundaram, Vijay; Muthukumarappan, Kasiviswanathan; Gent, Stephen

    2017-03-01

    Lignocellulosic feedstocks corn stover, prairie cord grass, and switchgrass were subjected to ammonia fiber expansion (AFEX™) pretreatment and densified using extrusion pelleting and ComPAKco densification technique. The effects of AFEX™ pretreatment and densification were studied on the fast pyrolysis product yields. Feedstocks were milled in a hammer mill using three different screen sizes (2, 4, and 8 mm) and were subjected to AFEX™ pretreatment. The untreated and AFEX™-pretreated feedstocks were moisture adjusted at three levels (5, 10, and 15 % wb) and were extruded using a lab-scale single screw extruder. The barrel temperature of the extruder was maintained at 75, 100, and 125 °C. Durability of the extruded pellets made from AFEX™-pretreated corn stover, prairie cord grass, and switchgrass varied from 94.5 to 99.2, 94.3 to 98.7, and 90.1 to 97.5 %, respectively. Results of the thermogravimetric analysis showed the decrease in the decomposition temperature of the all the feedstocks after AFEX™ pretreatment indicating the increase in thermal stability. Loose and densified feedstocks were subjected to fast pyrolysis in a lab-scale reactor, and the yields (bio-oil and bio-char) were measured. Bio-char obtained from the AFEX™-pretreated feedstocks exhibited increased bulk and particle density compared to the untreated feedstocks. The properties of the bio-oil were statistically similar for the untreated, AFEX™-pretreated, and AFEX™-pretreated densified feedstocks. Based on the bio-char and bio-oil yields, the AFEX™-pretreated feedstocks and the densified AFEX™-pretreated feedstocks (pellets and PAKs) exhibited similar behavior. Hence, it can be concluded that densifying the AFEX™-pretreated feedstocks could be a viable option in the biomass-processing depots to reduce the transportation costs and the logistical impediments without affecting the product yields.

  10. Magnitude of [14C] DDT residues in stored dried fish and pre-cooking processing effect on their removal

    International Nuclear Information System (INIS)

    Rahman, M.; Khatoon, J.; Matin, M.A.; Main, A.J.

    1998-01-01

    Residues of 14 C-DDT in stored dried fish was determined under ambient conditions for a 6 month period. Immediately after treatment, about 40% of the applied DDT was eliminated from surface of the dried fish with water washing. However, such removal was reduced to about 26% on storage for 6 months. Boiling of dried fish in water resulted in further removal of about 16% residues. In boiled dried fish, about 14% residues might remain and this could be removed by Soxhlet extraction. Surface extraction with hexane yielded about 80% of the residues immediately after treatment and the extractable residues decreased to about half the initial value of 6 months' storage. Dried fish residues, on surface extraction with water or hexane, when subjected to exhaustive Soxhlet extraction with methanol was found to result in further recovery of about 39-49% and 17-32%, respectively. Bound DDT residues were found to be about 5% in water washed dried fish samples and about 1.5% in case of hexane-extracted samples. Degradation of parent DDT to DDE and DDD was found. Maximum values of 16.58% DDE and 21.6% DDD were found in dried fish stored for 6 months. (author)

  11. RESIDUAL RISK ASSESSMENTS - RESIDUAL RISK ...

    Science.gov (United States)

    This source category previously subjected to a technology-based standard will be examined to determine if health or ecological risks are significant enough to warrant further regulation for Coke Ovens. These assesments utilize existing models and data bases to examine the multi-media and multi-pollutant impacts of air toxics emissions on human health and the environment. Details on the assessment process and methodologies can be found in EPA's Residual Risk Report to Congress issued in March of 1999 (see web site). To assess the health risks imposed by air toxics emissions from Coke Ovens to determine if control technology standards previously established are adequately protecting public health.

  12. Rheology of dilute acid hydrolyzed corn stover at high solids concentration

    Science.gov (United States)

    M.R. Ehrhardt; T.O. Monz; T.W. Root; R.K. Connelly; Tim Scott; D.J. Klingenberg

    2010-01-01

    The rheological properties of acid hydrolyzed corn stover at high solids concentration (20–35 wt.%) were investigated using torque rheometry. These materials are yield stress fluids whose rheological properties can be well represented by the Bingham model. Yield stresses increase with increasing solids concentration and decrease with increasing hydrolysis reaction...

  13. Visual soil structure effects of tillage and corn stover harvest in Iowa, U.S.A.

    Science.gov (United States)

    Excessive harvest of corn (Zea mays L.) stover for ethanol production has raised concerns regarding negative consequences on soil structure and physical quality. Visual soil structure assessment methods have the potential to help address these concerns through simple, straightforward on-farm evaluat...

  14. Ethanol production from hydrothermal pretreated corn stover with a loop reactor

    DEFF Research Database (Denmark)

    Xu, Jian; Thomsen, Mette Hedegaard; Thomsen, Anne Belinda

    2010-01-01

    Hydrothermal pretreatment on raw corn stover (RCS) with a loop reactor was investigated at 195 °C for different times varying between 10 min and 30 min. After pretreatment, the slurry was separated into water-insoluble solid (WIS) and liquid phase. Glucan and xylan were found in the both phases...

  15. Investigation of acetic acid-catalyzed hydrothermal pretreatment on corn stover

    DEFF Research Database (Denmark)

    Xu, Jian; Thomsen, Mette Hedegaard; Thomsen, Anne Belinda

    2010-01-01

    Acetic acid (AA)-catalyzed liquid hot water (LHW) pretreatments on raw corn stover (RCS) were carried out at 195 °C at 15 min with the acetic acid concentrations between 0 and 400 g/kg RCS. After pretreatment, the liquor fractions and water-insoluble solids (WIS) were collected separately and tes...

  16. A high-performance carbon derived from corn stover via microwave and slow pyrolysis for supercapacitors

    DEFF Research Database (Denmark)

    Jin, Hong; wang, Xiaomin; Shen, Yanbin

    2014-01-01

    Microwave and slow pyrolysis were conducted for converting corn stover to biochar. Chemical agents of sodium hydroxide and potassium hydroxide were used to progressively produce activated carbon. The pore structures and surface area of the samples were characterized by nitrogen adsorption...

  17. The in vitro fermentation of maize stover as affected by faecal ...

    African Journals Online (AJOL)

    The effect of different inoculum sources, obtained from the faeces of ungulates, i.e. horses (H), wildebeest (WB) and zebra (ZB) and combinations of inoculum sources on the fermentation of maize stover (MS) was investigated. Combined sources (CS) were: (1) H+WB, (2) H+ZB, (3) WB+ZB and (4) H+WB+ZB. Fresh faecal ...

  18. Effect of treatment and cultivar on the ensiling of corn stover

    Science.gov (United States)

    Nine cultivars of corn stover selected for ethanol potential were harvested (34 to 40% dry matter) and each ensiled with six treatments: untreated, lactic acid bacteria, cell-wall degrading enzymes, sulfuric acid, bacteria-enzyme combination and enzyme-acid combination. Ensiling was carried out in v...

  19. Pretreatment of corn stover using wet oxidation to enhance enzymatic digestibility

    DEFF Research Database (Denmark)

    Varga, E.; Schmidt, A.S.; Reczey, K.

    2003-01-01

    Corn stover is an abundant, promising raw material for fuel ethanol production. Although it has a high cellulose content, without pretreatment it resists enzymatic hydrolysis, like most lignocellulosic materials. Wet oxidation (water, oxygen, mild alkali or acid, elevated temperature and pressure...

  20. Enzymatic hydrolysis and fermentability of corn stover pretreated by lactic acid and/or acetic acid

    DEFF Research Database (Denmark)

    Xu, Jian; Thomsen, Mette Hedegaard; Thomsen, Anne Belinda

    2009-01-01

    Four different pretreatments with and without addition of low concentration organic acids were carried out on corn stover at 195 °C for 15 min. The highest xylan recovery of 81.08% was obtained after pretreatment without acid catalyst and the lowest of 58.78% after pretreatment with both acetic...

  1. Stover harvest impacts soil and hydrologic properties on three Minnesota farms

    Science.gov (United States)

    Stover is the material remaining after harvesting corn (Zea Mays L.) grain, which may be removed for a variety of purposes, but these material are also crucial for protecting and enriching soil properties. This research was conducted on-farm in collaboration to assess the impact of harvesting cobs (...

  2. Enhanced furfural production from raw corn stover employing a novel heterogeneous acid catalyst.

    Science.gov (United States)

    Li, Wenzhi; Zhu, Yuanshuai; Lu, Yijuan; Liu, Qiyu; Guan, Shennan; Chang, Hou-Min; Jameel, Hasan; Ma, Longlong

    2017-12-01

    With the aim to enhance the direct conversion of raw corn stover into furfural, a promising approach was proposed employing a novel heterogeneous strong acid catalyst (SC-CaC t -700) in different solvents. The novel catalyst was characterized by elemental analysis, N 2 adsorption-desorption, FT-IR, XPS, TEM and SEM. The developed catalytic system demonstrated superior efficacy for furfural production from raw corn stover. The effects of reaction temperature, residence time, catalyst loading, substrate concentration and solvent were investigated and optimized. 93% furfural yield was obtained from 150mg corn stover at 200°C in 100min using 45mg catalyst in γ-valerolactone (GVL). In comparison, 51.5% furfural yield was achieved in aqueous media under the same conditions (200°C, 5h, and 45mg catalyst), which is of great industrial interest. Furfural was obtained from both hemicelluloses and cellulose in corn stover, which demonstrated a promising routine to make the full use of biomass. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Corn stover harvest strategy effects on grain yield and soil quality indicators

    Science.gov (United States)

    The development of technologies to use cellulosic biomass as a feedstock for biofuel production was recognized as an important research focus because cellulose is a more widely-available feedstock than corn starch. Our objective was to compare various corn (Zea mays L.) stover harvest strategies to ...

  4. Optimization of dilute sulfuric acid pretreatment and enzymatic saccharification of corn stover for efficient ethanol production

    Science.gov (United States)

    Dilute acid pretreatment is a promising pretreatment technology for conversion of lignocellulosic biomass to fuel ethanol. Corn stover (supplied by a local farmer) used in this study contained 37.0±0.4% cellulose, 31.3±0.6% hemicelluloses, and 17.8±0.2% lignin. Generation of fermentable sugars from ...

  5. Comparative performance of precommercial cellulases hydrolyzing pretreated corn stover

    Science.gov (United States)

    2011-01-01

    Background Cellulases and related hydrolytic enzymes represent a key cost factor for biochemical conversion of cellulosic biomass feedstocks to sugars for biofuels and chemicals production. The US Department of Energy (DOE) is cost sharing projects to decrease the cost of enzymes for biomass saccharification. The performance of benchmark cellulase preparations produced by Danisco, DSM, Novozymes and Verenium to convert pretreated corn stover (PCS) cellulose to glucose was evaluated under common experimental conditions and is reported here in a non-attributed manner. Results Two hydrolysis modes were examined, enzymatic hydrolysis (EH) of PCS whole slurry or washed PCS solids at pH 5 and 50°C, and simultaneous saccharification and fermentation (SSF) of washed PCS solids at pH 5 and 38°C. Enzymes were dosed on a total protein mass basis, with protein quantified using both the bicinchoninic acid (BCA) assay and the Bradford assay. Substantial differences were observed in absolute cellulose to glucose conversion performance levels under the conditions tested. Higher cellulose conversion yields were obtained using washed solids compared to whole slurry, and estimated enzyme protein dosages required to achieve a particular cellulose conversion to glucose yield were extremely dependent on the protein assay used. All four enzyme systems achieved glucose yields of 90% of theoretical or higher in SSF mode. Glucose yields were reduced in EH mode, with all enzymes achieving glucose yields of at least 85% of theoretical on washed PCS solids and 75% in PCS whole slurry. One of the enzyme systems ('enzyme B') exhibited the best overall performance. However in attaining high conversion yields at lower total enzyme protein loadings, the relative and rank ordered performance of the enzyme systems varied significantly depending upon which hydrolysis mode and protein assay were used as the basis for comparison. Conclusions This study provides extensive information about the

  6. Comparative performance of precommercial cellulases hydrolyzing pretreated corn stover

    Directory of Open Access Journals (Sweden)

    Mohagheghi Ali

    2011-09-01

    Full Text Available Abstract Background Cellulases and related hydrolytic enzymes represent a key cost factor for biochemical conversion of cellulosic biomass feedstocks to sugars for biofuels and chemicals production. The US Department of Energy (DOE is cost sharing projects to decrease the cost of enzymes for biomass saccharification. The performance of benchmark cellulase preparations produced by Danisco, DSM, Novozymes and Verenium to convert pretreated corn stover (PCS cellulose to glucose was evaluated under common experimental conditions and is reported here in a non-attributed manner. Results Two hydrolysis modes were examined, enzymatic hydrolysis (EH of PCS whole slurry or washed PCS solids at pH 5 and 50°C, and simultaneous saccharification and fermentation (SSF of washed PCS solids at pH 5 and 38°C. Enzymes were dosed on a total protein mass basis, with protein quantified using both the bicinchoninic acid (BCA assay and the Bradford assay. Substantial differences were observed in absolute cellulose to glucose conversion performance levels under the conditions tested. Higher cellulose conversion yields were obtained using washed solids compared to whole slurry, and estimated enzyme protein dosages required to achieve a particular cellulose conversion to glucose yield were extremely dependent on the protein assay used. All four enzyme systems achieved glucose yields of 90% of theoretical or higher in SSF mode. Glucose yields were reduced in EH mode, with all enzymes achieving glucose yields of at least 85% of theoretical on washed PCS solids and 75% in PCS whole slurry. One of the enzyme systems ('enzyme B' exhibited the best overall performance. However in attaining high conversion yields at lower total enzyme protein loadings, the relative and rank ordered performance of the enzyme systems varied significantly depending upon which hydrolysis mode and protein assay were used as the basis for comparison. Conclusions This study provides extensive

  7. Corn stover fractions as a function of hybrid, maturity, site and year

    Energy Technology Data Exchange (ETDEWEB)

    Lizotte, P.L. [Laval Univ., Quebec City, PQ (Canada). Dept. des sols et de genie agroalimentaire; Savoie, P. [Agriculture and Agri-Food Canada, Quebec City, PQ (Canada); Lefsrud, M. [McGill Univ., Macdonald College, Ste-Anne-de-Bellevue, PQ (Canada). Dept. of Biosystems Engineering

    2010-07-01

    Corn stover is usually left on the ground following corn harvest so that it can be incorporated into the soil as organic matter and to protect against erosion. Part of the corn stover is oxidized in the atmosphere. Corn stover represents between 40 and 50 per cent of the dry matter (DM) contained in the aerial biomass of corn plants. Recent studies have shown that half of the corn stover could be harvested sustainably on low-sloping land under no-till practice. In Quebec, where 400,000 ha of corn are planted each year, corn stover could provide one million t DM of currently neglected biomass. Various hybrids of corn were monitored from early September to late November at 4 different sites during 2007, 2008 and 2009. Whole plants cut at 100 mm above the ground were collected weekly and separated into 7 fractions, notably the grain, the cob, the husk, the stalk below the ear, the stalk above the ear, the leaves below the ear and the leaves above the ear. In 2007, corn ears on average, were at 0.96 m above the ground at a site with low crop heat units (CHU). Hybrids grown in a warmer site were taller and their ears were 1.21 m above the ground. The DM partitioned in 7 components was 54 per cent grain, 14 per cent bottom stalk, 6 per cent top stalk, 5 per cent bottom leaves, 7 per cent top leaves, 5 per cent husk and 9 per cent cob. The total mass of fibre during harvest decreased from 8.9 to 6.6 t DM/ha for a low CHU hybrid and from 9.3 to 8.3 t DM/ha for a high CHU hybrid. Grain yield increased in 2008 from 3.8 to 7.6 t DM/ha over a 12-week period.

  8. The influence of tomato processing on residues of organochlorine and organophosphate insecticides and their associated dietary risk.

    Science.gov (United States)

    Reiler, Emilie; Jørs, Erik; Bælum, Jesper; Huici, Omar; Alvarez Caero, Maria Mercedes; Cedergreen, Nina

    2015-09-15

    Due to the increasing food demand, the use of pesticides in agriculture is increasing. Particularly in low income countries poor training among farmers, combined with the use of obsolete pesticides may result in a high risk for the consumers. In this study six organochlorines and five organophosphates were analyzed in 54 samples of tomatoes from small scale farmers in Bolivia. The analyses were done on unprocessed, stored, washed and peeled tomatoes. The cumulated risk associated with consumption of the tomatoes after different storage times and processing treatments was evaluated using the Hazard Index (HI) for acute risk assessment. All 11 pesticides were detected in the analyses although several of them are obsolete and included in the Stockholm convention ratified by Bolivia. The organochlorines were found in the μg pesticide/kg tomato range and below the HI, while the organophosphates were present in the mg pesticide/kg tomato range and most often above the HI. The low organochlorine concentrations were not significantly affected by time or treatment, but storage significantly decreased the concentrations of organophosphates. Washing decreased the initial concentrations to between 53% (malathion) down to 2% (ethyl parathion), while peeling had a larger effect reducing the initial concentrations to between 33% (malathion) and 0.7% (chlorpyriphos). Both the acute and chronic cumulative risk assessment of organophosphates showed a dietary risk for unprocessed tomatoes three days after harvest. For children, also the consumption of washed tomatoes constituted a dietary risk. To reduce the dietary risk of pesticide residues in Bolivia, there is an urgent need of farmer education and introduction of less hazardous pesticides as well as resources for surveillance and enforcement of legislation in order to ensure public health. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Microscopic residual stress evolution during deformation process of an Fe---Mn---Si---Cr shape memory alloy investigated using white X-ray microbeam diffraction

    International Nuclear Information System (INIS)

    Kwon, E.P.; Sato, S.; Fujieda, S.; Shinoda, K.; Kajiwara, K.; Sato, M.; Suzuki, S.

    2013-01-01

    Microscopic residual stress evolution in different austenite (γ) grains during shape memory process in an Fe---Mn---Si---Cr alloy was investigated using the white X-ray microbeam diffraction technique. The use of high-energy white X-ray microbeam with small beam size allowed us to measure the microscopic residual stress in coarse γ grains with specific orientation. After tensile deformation large compressive residual stress was evolved in γ grains due to the formation of stress-induced ε martensite, but upon recovery heating it almost disappeared as a result of reverse transformation of martensite. The magnitude of compressive residual stress was higher in grains with orientations close to 〈144〉 and 〈233〉 orientations than in a grain with near 〈001〉 orientation. Analysis of the microstructure of each grain using electron backscattering diffraction suggested that the difference in the magnitude of compressive residual stress could be attributed to different martensitic transformation characteristics in the grains

  10. Effect of Welding Processes on the Microstructure, Mechanical Properties and Residual Stresses of Plain 9Cr-1Mo Steel Weld Joints

    Science.gov (United States)

    Nagaraju, S.; Vasantharaja, P.; Brahadees, G.; Vasudevan, M.; Mahadevan, S.

    2017-12-01

    9Cr-1Mo steel designated as P9 is widely used in the construction of power plants and high-temperature applications. It is chosen for fabricating hexcan fuel subassembly wrapper components of fast breeder reactors. Arc welding processes are generally used for fabricating 9Cr-1Mo steel weld joints. A-TIG welding process is increasingly being adopted by the industries. In the present study, shielded metal arc (SMA), tungsten inert gas (TIG) and A-TIG welding processes are used for fabricating the 9Cr-1Mo steel weld joints of 10 mm thickness. Effect of the above welding processes on the microstructure evolution, mechanical properties and residual stresses of the weld joints has been studied in detail. All the three weld joints exhibited comparable strength and ductility values. 9Cr-1Mo steel weld joint fabricated by SMAW process exhibited lower impact toughness values caused by coarser grain size and inclusions. 9Cr-1Mo steel weld joint fabricated by TIG welding exhibited higher toughness due to finer grain size, while the weld joint fabricated by A-TIG welding process exhibited adequate toughness values. SMA steel weld joint exhibited compressive residual stresses in the weld metal and HAZ, while TIG and A-TIG weld joint exhibited tensile residual stresses in the weld metal and HAZ.

  11. Remediation of hexavalent chromium contamination in chromite ore processing residue by sodium dithionite and sodium phosphate addition and its mechanism.

    Science.gov (United States)

    Li, Yunyi; Cundy, Andrew B; Feng, Jingxuan; Fu, Hang; Wang, Xiaojing; Liu, Yangsheng

    2017-05-01

    Large amounts of chromite ore processing residue (COPR) wastes have been deposited in many countries worldwide, generating significant contamination issues from the highly mobile and toxic hexavalent chromium species (Cr(VI)). In this study, sodium dithionite (Na 2 S 2 O 4 ) was used to reduce Cr(VI) to Cr(III) in COPR containing high available Fe, and then sodium phosphate (Na 3 PO 4 ) was utilized to further immobilize Cr(III), via a two-step procedure (TSP). Remediation and immobilization processes and mechanisms were systematically investigated using batch experiments, sequential extraction studies, X-ray diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). Results showed that Na 2 S 2 O 4 effectively reduced Cr(VI) to Cr(III), catalyzed by Fe(III). The subsequent addition of Na 3 PO 4 further immobilized Cr(III) by the formation of crystalline CrPO 4 ·6H 2 O. However, addition of Na 3 PO 4 simultaneously with Na 2 S 2 O 4 (via a one-step procedure, OSP) impeded Cr(VI) reduction due to the competitive reaction of Na 3 PO 4 and Na 2 S 2 O 4 with Fe(III). Thus, the remediation efficiency of the TSP was much higher than the corresponding OSP. Using an optimal dosage in the two-step procedure (Na 2 S 2 O 4 at a dosage of 12× the stoichiometric requirement for 15 days, and then Na 3 PO 4 in a molar ratio (i.e. Na 3 PO 4 : initial Cr(VI)) of 4:1 for another 15 days), the total dissolved Cr in the leachate determined via Toxicity Characteristic Leaching Procedure (TCLP Cr) testing of our samples was reduced to 3.8 mg/L (from an initial TCLP Cr of 112.2 mg/L, i.e. at >96% efficiency). Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Compatibility of High-Moisture Storage for Biochemical Conversion of Corn Stover: Storage Performance at Laboratory and Field Scales

    Science.gov (United States)

    Wendt, Lynn M.; Murphy, J. Austin; Smith, William A.; Robb, Thomas; Reed, David W.; Ray, Allison E.; Liang, Ling; He, Qian; Sun, Ning; Hoover, Amber N.; Nguyen, Quang A.

    2018-01-01

    Wet anaerobic storage of corn stover can provide a year-round supply of feedstock to biorefineries meanwhile serving an active management approach to reduce the risks associated with fire loss and microbial degradation. Wet logistics systems employ particle size reduction early in the supply chain through field-chopping which removes the dependency on drying corn stover prior to baling, expands the harvest window, and diminishes the biorefinery size reduction requirements. Over two harvest years, in-field forage chopping was capable of reducing over 60% of the corn stover to a particle size of 6 mm or less. Aerobic and anaerobic storage methods were evaluated for wet corn stover in 100 L laboratory reactors. Of the methods evaluated, traditional ensiling resulted in biofuel production. Evaluation of the operational efficiencies and costs is suggested to quantify the potential benefits of a fully-wet biomass supply system to a commercial biorefinery. PMID:29632861

  13. Quantifying cradle-to-farm gate life-cycle impacts associated with fertilizer used for corn, soybean, and stover production

    Energy Technology Data Exchange (ETDEWEB)

    Powers, Susan E. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2005-05-01

    Fertilizer use can cause environmental problems, particularly eutrophication of water bodies from excess nitrogen or phosphorus. Increased fertilizer runoff is a concern for harvesting corn stover for ethanol production.

  14. Corn fiber, cobs and stover: Enzyme-aided saccharification and co-fermentation after dilute acid pretreatment

    NARCIS (Netherlands)

    Eylen, van D.; Dongen, van F.E.M.; Kabel, M.A.; Bont, de J.A.M.

    2011-01-01

    Three corn feedstocks (fibers, cobs and stover) available for sustainable second generation bioethanol production were subjected to pretreatments with the aim of preventing formation of yeast-inhibiting sugar-degradation products. After pretreatment, monosaccharides, soluble oligosaccharides and

  15. Comparative studies on thermochemical characterization of corn stover pretreated by white-rot and brown-rot fungi.

    Science.gov (United States)

    Zeng, Yelin; Yang, Xuewei; Yu, Hongbo; Zhang, Xiaoyu; Ma, Fuying

    2011-09-28

    The effects of white-rot and brown-rot fungal pretreatment on the chemical composition and thermochemical conversion of corn stover were investigated. Fungus-pretreated corn stover was analyzed by Fourier transform infrared spectroscopy and X-ray diffraction analysis to characterize the changes in chemical composition. Differences in thermochemical conversion of corn stover after fungal pretreatment were investigated using thermogravimetric and pyrolysis analysis. The results indicated that the white-rot fungus Irpex lacteus CD2 has great lignin-degrading ability, whereas the brown-rot fungus Fomitopsis sp. IMER2 preferentially degrades the amorphous regions of the cellulose. The biopretreatment favors thermal decomposition of corn stover. The weight loss of IMER2-treated acid detergent fiber became greater, and the oil yield increased from 32.7 to 50.8%. After CD2 biopretreatment, 58% weight loss of acid detergent lignin was achieved and the oil yield increased from 16.8 to 26.8%.

  16. An in-depth analysis of the physico-mechanical properties imparted by agricultural fibers and food processing residues in polypropylene biocomposites

    Science.gov (United States)

    Murdy, Rachel Campbell; Mak, Michelle; Misra, Manjusri; Mohanty, Amar K.

    2015-05-01

    The use of agricultural and food processing residues as potential reinforcements in plastics has been extensively studied. However, there is a large variation in the mechanical performance of agricultural fiber-based biocomposites due to different processing materials and parameters. An in-depth comparison of the resulting effect of the agricultural filler on the matrix is often not possible given the discrepancy in processing conditions. This study seeks to determine the intrinsic properties of agricultural fibers and food processing residues for their use in polypropylene biocomposites based on a standardization of experimental design. The effect of 25wt% loading of miscanthus, fall-and spring-harvest switchgrass, wheat straw, oat hull, soy hull, soy stalk, hemp and flax on the physico-mechanical properties of polypropylene biocomposites was investigated. The addition of fiber led to an improvement in flexural strength, flexural modulus, and tensile modulus, and a general decrease in tensile strength at yield, elongation at break and Izod impact strength. Scanning electron microscopy highlighted the interfacial adhesion, orientation and distribution of the fibers within the matrix, confirming that fiber length and dispersion within the matrix are positively correlated with mechanical properties. The crystallization of the polypropylene phase and a compositional analysis of the agricultural fibers and processing residues were also compared to offer insight into the effect of the filler's intrinsic properties on the resulting material performance.

  17. An in-depth analysis of the physico-mechanical properties imparted by agricultural fibers and food processing residues in polypropylene biocomposites

    International Nuclear Information System (INIS)

    Murdy, Rachel Campbell; Mak, Michelle; Misra, Manjusri; Mohanty, Amar K.

    2015-01-01

    The use of agricultural and food processing residues as potential reinforcements in plastics has been extensively studied. However, there is a large variation in the mechanical performance of agricultural fiber-based biocomposites due to different processing materials and parameters. An in-depth comparison of the resulting effect of the agricultural filler on the matrix is often not possible given the discrepancy in processing conditions. This study seeks to determine the intrinsic properties of agricultural fibers and food processing residues for their use in polypropylene biocomposites based on a standardization of experimental design. The effect of 25wt% loading of miscanthus, fall-and spring-harvest switchgrass, wheat straw, oat hull, soy hull, soy stalk, hemp and flax on the physico-mechanical properties of polypropylene biocomposites was investigated. The addition of fiber led to an improvement in flexural strength, flexural modulus, and tensile modulus, and a general decrease in tensile strength at yield, elongation at break and Izod impact strength. Scanning electron microscopy highlighted the interfacial adhesion, orientation and distribution of the fibers within the matrix, confirming that fiber length and dispersion within the matrix are positively correlated with mechanical properties. The crystallization of the polypropylene phase and a compositional analysis of the agricultural fibers and processing residues were also compared to offer insight into the effect of the filler’s intrinsic properties on the resulting material performance

  18. An in-depth analysis of the physico-mechanical properties imparted by agricultural fibers and food processing residues in polypropylene biocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Murdy, Rachel Campbell; Mak, Michelle [Bioproducts Discovery and Development Centre, Department of Plant Agriculture, Crop Science Building, University of Guelph, Guelph, ON N1G 2W1 (Canada); Misra, Manjusri; Mohanty, Amar K. [Bioproducts Discovery and Development Centre, Department of Plant Agriculture, Crop Science Building, University of Guelph, Guelph, ON N1G 2W1 (Canada); School of Engineering, Thornbrough Building, University of Guelph, ON N1G 2W1 (Canada)

    2015-05-22

    The use of agricultural and food processing residues as potential reinforcements in plastics has been extensively studied. However, there is a large variation in the mechanical performance of agricultural fiber-based biocomposites due to different processing materials and parameters. An in-depth comparison of the resulting effect of the agricultural filler on the matrix is often not possible given the discrepancy in processing conditions. This study seeks to determine the intrinsic properties of agricultural fibers and food processing residues for their use in polypropylene biocomposites based on a standardization of experimental design. The effect of 25wt% loading of miscanthus, fall-and spring-harvest switchgrass, wheat straw, oat hull, soy hull, soy stalk, hemp and flax on the physico-mechanical properties of polypropylene biocomposites was investigated. The addition of fiber led to an improvement in flexural strength, flexural modulus, and tensile modulus, and a general decrease in tensile strength at yield, elongation at break and Izod impact strength. Scanning electron microscopy highlighted the interfacial adhesion, orientation and distribution of the fibers within the matrix, confirming that fiber length and dispersion within the matrix are positively correlated with mechanical properties. The crystallization of the polypropylene phase and a compositional analysis of the agricultural fibers and processing residues were also compared to offer insight into the effect of the filler’s intrinsic properties on the resulting material performance.

  19. 3-D numerical evaluation of residual stress and deformation due welding process using simplified heat source models

    Energy Technology Data Exchange (ETDEWEB)

    Eslampanah, Amir Hossein [Islamic Azad University, Arak (Iran, Islamic Republic of); Aalami-aleagha, Mohammad Ebrahim; Feli, Saeid [Razi University, Kermanshah (Iran, Islamic Republic of); Ghaderi, Mohammad Reza [Islamic Azad University, Sanandaj (Iran, Islamic Republic of)

    2015-01-15

    Thermal elastic-plastic finite element method has been employed to predict residual stress and deformation in a T-Fillet welded joint. An uncoupled thermal-mechanical three-dimensional (3-D) model has been developed. A nonlinear-transient heat flow analysis was used to obtain the temperature distribution; then by applying thermal results in the three dimensional elastic-plastic model, residual stress and deformation distribution were obtained. Experiments were carried out to find fusion zone dimensions and displacement. Two heat source models with infinite speed are proposed and the mechanical result of the mentioned models and normal moving heat source are compared.

  20. Effect of grain storage and processing on chlorpyrifos-methyl and pirimiphos-methyl residues in post-harvest-treated wheat with regard to baby food safety requirements.

    Science.gov (United States)

    Balinova, A; Mladenova, R; Obretenchev, D

    2006-04-01

    A study was undertaken to assess the effects of storage intervals and of milling procedures on the dissipation of chlorpyrifos-methyl and pirimiphos-methyl residues in post-harvest-treated wheat grain and to obtain scientific data on the compliance of the processed products with safety requirements concerning baby foods. The insecticide formulations were applied on stored wheat at recommended rates (20 ml t(-1)). The initial concentration levels in whole grain were determined in samples taken 1 h after treatment. The dissipation of residues and their distribution in different fractions of the milled grain were studied after various storage intervals, from 7 to 270 days after treatment. Samples of treated grain were milled in a fractionating laboratory mill and eight fractions--bran, semolina, three types of groats and three types of flour--were collected and analysed for pesticide residues. The residues were determined by an analytical method based on acetone extraction, graphitized carbon clean-up and GC-ECD, respectively, and GC-NPD determination of residues. The limits of determination of both pesticides were 0.005 mg kg(-1), which is high enough for enforcement of the European Commission Directive that established a maximum residue level of 0.01 mg kg(-1) for any pesticide in cereal-based baby food. The results showed that the pesticides chlorpyrifos-methyl and pirimiphos-methyl applied post-harvest on wheat as grain protectants were distinguished by relatively low rates of degradation in the grain under practical storage conditions. Milling did not significantly reduce the bulk of the chemicals but resulted in the distribution of residues in various processed products. The main part of the insecticides deposited on the grain remained in the bran and partly in semolina fractions. After 270 days of treatment, the residues of chlorpyrifos-methyl were within the range 0.8-2.1 mg kg(-1) and of pirimiphos-methyl - between 0.6 and 3.7 mg kg(-1) in the various types

  1. Quantifying Cradle-to-Farm Gate Life-Cycle Impacts Associated with Fertilizer used for Corn, Soybean, and Stover Production

    Energy Technology Data Exchange (ETDEWEB)

    Powers, S. E.

    2005-05-01

    Fertilizer use can cause environmental problems, particular eutrophication of water bodies from excess nitrogen or phosphorus. Increased fertilizer runoff is a concern for harvesting corn stover for ethanol production. This modeling study found that eutrophication potential for the base case already exceeds proposed water quality standards, that switching to no-till cultivation and collecting stover increased that eutrophication potential by 21%, and that switching to continuous-corn production on top of that would triple eutrophication potential.

  2. Influence of arbuscular mycorrhizal fungi on the growth and nutrient status of bermudagrass grown in alkaline bauxite processing residue

    International Nuclear Information System (INIS)

    Giridhar Babu, A.; Sudhakara Reddy, M.

    2011-01-01

    A nursery experiment was conducted to evaluate the potential role of arbuscular mycorrhizal (AM) fungi in encouraging the vegetation cover on bauxite residue (red mud) sites. An alkali tolerant bermudagrass (Cynodon dactylon) adapted to local conditions were grown in red mud with different amendments with and without AM fungi to assess mycorrhizal effects on plant growth, mineral nutrition, metal uptake and neutralization of bauxite residue. Inoculation of AM fungi significantly increased the plant growth, nutrient uptake and reduced Fe, Al accumulation in plant tissue and also improved the soil physico-chemical and biochemical properties. Gypsum and sludge amended treatments inoculated with AM fungi had maximum biomass, nutrient uptake and reduced accumulation of metals. The neutralization of red mud was significant in presence of AM fungi than control. The experiment provided evidence for the potential use of bermudagrass in combination with AM fungi for ecological restoration of bauxite residue sites. - Inoculation of red mud tolerant AM fungi enhanced the growth and nutrient status of bermudagrass and the physico-chemical properties of the bauxite residues amended with gypsum or sewage sludge.

  3. Residual effects of low oxygen storage of mature green fruit on ripening processes and ester biosynthesis during ripening in bananas

    Science.gov (United States)

    Mature green banana (Musa sapientum L. cv. Cavendish) fruit were stored in 0.5%, 2 %, or 21% O2 for 7 days at 20 °C before ripening was initiated by ethylene. Residual effects of low O2 storage in mature green fruit on ripening and ester biosynthesis in fruit were investigated during ripening period...

  4. Influence of arbuscular mycorrhizal fungi on the growth and nutrient status of bermudagrass grown in alkaline bauxite processing residue

    Energy Technology Data Exchange (ETDEWEB)

    Giridhar Babu, A., E-mail: anamgiri@gmail.co [Department of Biotechnology, Thapar University, Patiala 147 004 (India); Sudhakara Reddy, M., E-mail: msreddy@thapar.ed [Department of Biotechnology, Thapar University, Patiala 147 004 (India)

    2011-01-15

    A nursery experiment was conducted to evaluate the potential role of arbuscular mycorrhizal (AM) fungi in encouraging the vegetation cover on bauxite residue (red mud) sites. An alkali tolerant bermudagrass (Cynodon dactylon) adapted to local conditions were grown in red mud with different amendments with and without AM fungi to assess mycorrhizal effects on plant growth, mineral nutrition, metal uptake and neutralization of bauxite residue. Inoculation of AM fungi significantly increased the plant growth, nutrient uptake and reduced Fe, Al accumulation in plant tissue and also improved the soil physico-chemical and biochemical properties. Gypsum and sludge amended treatments inoculated with AM fungi had maximum biomass, nutrient uptake and reduced accumulation of metals. The neutralization of red mud was significant in presence of AM fungi than control. The experiment provided evidence for the potential use of bermudagrass in combination with AM fungi for ecological restoration of bauxite residue sites. - Inoculation of red mud tolerant AM fungi enhanced the growth and nutrient status of bermudagrass and the physico-chemical properties of the bauxite residues amended with gypsum or sewage sludge.

  5. Comparison of Chemical Composition and Energy Property of Torrefied Switchgrass and Corn Stover

    International Nuclear Information System (INIS)

    Tumuluru, Jaya Shankar

    2015-01-01

    In the present study, 6-mm ground corn stover and switchgrass were torrefied in temperatures ranging from 180 to 270°C for 15- to 120-min residence time. Thermogravimetric analyzer was used to do the torrefaction studies. At a torrefaction temperature of 270°C and a 30-min residence time, the weight loss increased to >45%. At 180°C and 120 min, there was about 56 and 73% of moisture loss in the corn stover and switchgrass; further increasing the temperature to 270°C and 120 min resulted in about 78.8–88.18% moisture loss in both the feedstock. Additionally, at these temperatures, there was a significant decrease in the volatile content and increase in the fixed carbon content, and the ash content for both the biomasses tested. The ultimate composition like carbon content increased and hydrogen content decreased with increase in the torrefaction temperature and time. At 270°C and 120-min residence time, the carbon content observed was 56.63 and 58.04% and hydrogen content observed was 2.74 and 3.14%. Nitrogen and sulfur content measured at 270°C and 120 min were 0.98, 0.8, 0.076, and 0.07% for both the corn stover and switchgrass. The hydrogen/carbon and oxygen/carbon ratios calculated decreased to the lowest values of 0.59 and 0.64, and 0.71 and 0.76 for both biomasses. The van Krevelen diagram drawn for corn stover and switchgrass torrefied at 270°C indicated that H/C and O/C values are closer to coals like Illinois Basis and Powder River Basin. In the present study, the maximum higher heating value that was observed by corn stover and switchgrass was 21.51 and 21.53 MJ/kg at 270°C and a 120-min residence time. From these results, it can be concluded that corn stover and switchgrass, after torrefaction, shows consistent proximate, ultimate, and energy properties.

  6. Computational fluid dynamics (CFD) analysis of the combustion process of a leather residuals gasification fuel gas: influence of fuel moisture content

    Energy Technology Data Exchange (ETDEWEB)

    Antonietti, Anderson Jose; Beskow, Arthur Bortolin; Silva, Cristiano Vitorino da [Universidade Regional Integrada do Alto Uruguai e das Missoes (URI), Erechim, RS (Brazil)], E-mails: arthur@uricer.edu.br, mlsperb@unisinos.br; Indrusiak, Maria Luiza Sperb [Universidade do Vale do Rio dos Sinos (UNISINOS), Sao Leopoldo, RS (Brazil)], E-mail: cristiano@uricer.edu.br

    2010-07-01

    This work presents a numerical study of the combustion process of leather residuals gasification gas, aiming the improvement of the process efficiency, considering different concentrations of water on the gas. The heating produced in this combustion process can be used to generation of thermal and/or electrical energy, for use at the leather industrial plant. However, the direct burning of this leather-residual-gas into the chambers is not straightforward. The alternative in development consists in processing this leather residuals by gasification or pyrolysis, separating the volatiles and products of incomplete combustion, for after use as fuel in a boiler. At these processes, different quantities of water can be used, resulting at different levels of moisture content in this fuel gas. This humidity can affect significantly the burning of this fuel, producing unburnt gases, as the carbon monoxide, or toxic gases as NOx, which must have their production minimized on the process, with the purpose of reducing the emission of pollutants to the atmosphere. Other environment-harmful-gases, remaining of the chemical treatment employed at leather manufacture, as cyanide, and hydrocarbons as toluene, must burn too, and the moisture content has influence on it. At this way, to increase understanding of the influence of moisture in the combustion process, it was made a numerical investigation study of reacting flow in the furnace, evaluating the temperature field, the chemical species concentration fields, flow mechanics and heat transfer at the process. The commercial CFD code CFX Ansys Inc. was used. Considering different moisture contents in the fuel used on the combustion process, with this study was possible to achieve the most efficient burning operation parameters, with improvement of combustion efficiency, and reduction of environmental harmful gases emissions. It was verified that the different moisture contents in the fuel gas demand different operation conditions

  7. A novel feedstuff: ensiling of cowpea (Vigna unguiculata L.) stover and apple (Malus domestica Borkh.) mixtures. Evaluation of the nutritive value, fermentation quality and aerobic stability.

    Science.gov (United States)

    Andrade, Ederson; Gonçalves, Alexandre; Mendes-Ferreira, Ana; Silva, Valéria; Pinheiro, Victor; Rodrigues, Miguel; Ferreira, Luis

    2017-10-01

    Agro-industrial by-products are of low economic value as foods for human consumption but may have potential value as animal feedstuffs. This study evaluated a novel feedstuff, ensiled discarded apple (85%) and cowpea stover (15%) mixtures with two different ensiling periods (45 and 60 days), regarding the nutritive value, fermentation quality and aerobic stability. Generally, no differences (P > 0.05) were observed between ensiling periods for nutritive value and fermentation characteristics. Silages were stable after ensiling, presenting high lactic acid (77.3 g kg -1 dry matter (DM)) and acetic acid (54.7 g kg -1 DM) and low ethanol (15.7 g kg -1 DM) and NH 3 -N (105.6 g kg -1 total N) concentrations. No butyric acid was detected in silages, and they were aerobically stable for up to 216 h. Lactic acid bacteria numbers were high at silo opening (7.14 log colony-forming units (CFU) g -1 ), while Enterobacteriaceae were not detected and yeasts/moulds were low (2.44 log CFU g -1 ). Yeast/mould and Enterobacteriaceae numbers grew considerably during 12 days of air exposure. A mixture of low calibre discarded apples with cowpea stover can be used as animal feed after the ensiling process owing to its nutritive value and long aerobic stability. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  8. Production of a lignocellulolytic enzyme system for simultaneous bio-delignification and saccharification of corn stover employing co-culture of fungi.

    Science.gov (United States)

    Ma, Kedong; Ruan, Zhiyong

    2015-01-01

    Aiming at improving the efficiency of transferring corn stover into sugars, an efficient lignocellulolytic enzyme system was developed and investigated by co-cultivation of the Coprinus comatus with Trichoderma reesei in a single bioreactor. The results showed that the lignocellulolytic enzyme activities of the co-culture exceeded that of the monoculture, suggesting synergistic interaction between two fungi. The highest laccase activity from the co-culture was 2.6-fold increase over that of the C. comatus monoculture and reached a peak 3days earlier. The maximum delignification obtained was 66.5% and about 82% of the original polysaccharides were converted into fermentable sugars by simultaneous bio-delignification and saccharification process. Correlation analysis showed that sugar yields were directly proportional to the lignin degradation. Our results suggested that co-fungi cultivation was a valuable technique for corn stover bioconversion, which could produce high efficiency of lignocellulolytic enzyme system as a cheaper alternative to commercial enzymes for industrial utilization. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Implementation of sustainable processes in regional industries: recycling of metallurgical residual as a project to chance masonry used in construction in Bogotá, Colombia.

    Directory of Open Access Journals (Sweden)

    Leonardo Quijano B.

    2014-03-01

    Full Text Available Rev.esc.adm.neg This paper shows the analysis of the possibilities to implement a new process, viable from the environmental and economic point of view, which includes two regional industries within the framework of the generation of sustainable solutions for the regional economy. In it, the description of how to use residuals from the steel industry as a source to transform the masonry industry, both located in the region of Bogota.

  10. Sevin residues in groundnut varieties and the effect of commercial processing procedures on the fate of 14C sevin in groundnut oil

    International Nuclear Information System (INIS)

    Mendes, M.G.; Murthy, N.B.K.; Raghu, K.

    1980-01-01

    Groundnut varieties, Spanish Improved, J-11, TG-8 and TG-9 were sprayed with sevin (1-Naphthyl, N-methylcarbamate) at the recommended field dose. The oil extracted from harvested groundnut kernel did not show any detectable residues as sevin. Crude groundnut oil, when fortified with 14 C sevin, and the oil subjected to commercial processing techniques of alkali refining and bleaching, removed nearly 67% of the total 14 C radioactivity initially added. (author)

  11. Effect of welding processes and joint configuration on the residual stresses and distortion in type 316 LN stainless steel weld joints

    International Nuclear Information System (INIS)

    Vasantharaja, P.; Vasudevan, M.; Palanichamy, P.

    2012-01-01

    Fabrication by welding introduces significant residual stresses in the welded structure/component due to non-uniform heat distribution during heating and cooling cycle. To control, reduce, or beneficially redistribute the residual stresses in weld joints, the stress distribution needs to be known. In the present study, weld joints of 16 mm thick 316LN stainless steel were made by multi-pass TIG, A-TIG welding and combination of TIG and A-TIG welding processes with various joint configurations. While V-groove edge preparation was required for making multi-pass TIG weld joint, square-edge preparation was sufficient for making A-TIG weld joint. Ultrasonic nondestructive technique based on the critically refracted longitudinal waves (LCR waves) has been used for the quantitative surface/sub-surface residual stress measurements in the weld joints. Distortion measurements were carried out before and after welding using height gauge. A-TIG weld joint was found to exhibit significant reduction in tensile residual stresses and distortion in comparison to that of other joints. (author)

  12. Effects of laccase on lignin depolymerization and enzymatic hydrolysis of ensiled corn stover.

    Science.gov (United States)

    Chen, Qin; Marshall, Megan N; Geib, Scott M; Tien, Ming; Richard, Tom L

    2012-08-01

    The aim of this study was to explore the synergies of laccase, a ligninolytic enzyme, with cellulose and hemicellulase amendments on ensiled corn stover. Molecular signals of lignin decomposition were observed by tetramethylammonium hydroxide thermochemolysis and gas chromatography-mass spectroscopy (TMAH-GC-MS) analysis. The significant findings suggest that ensilage might provide a platform for biological pretreatment. By partially hydrolyzing cellulose and hemicellulose into soluble sugars, ensilage facilitates laccase penetration into the lignocellulose complex to enhance lignin degradation. Downstream cellulose hydrolysis was improved 7% with increasing laccase loading rate. These results demonstrate the potential of enzymes, either directly amended or expressed by microbes during ensilage, to maximize utilization of corn stover for cellulosic biofuels and other downstream fermentations. Copyright © 2012. Published by Elsevier Ltd.

  13. OPTIMIZATION OF SODA PULPING PROCESS OF LIGNO-CELLULOSIC RESIDUES OF LEMON AND SOFIA GRASSES PRODUCED AFTER STEAM DISTILLATION

    OpenAIRE

    Harjeet Kaur; Dharm Dutt; C. H. Tyagi

    2011-01-01

    Sofia (Cymbopogon martini), and lemon (Cymbopogon flexuosus) grasses, are exclusively cultivated for extraction of important lemongrass and palma rosa oils. Lignocellulosic residue (LCR) of sofia and lemon grasses left after steam distillation can successfully be used for the production of chemical grade pulp. Steam distillation mitigates the problem of mass transfer, and facilitates the faster penetration of cooking liquor by leaching out a part of extraneous components. Sofia grass produces...

  14. Residuation theory

    CERN Document Server

    Blyth, T S; Sneddon, I N; Stark, M

    1972-01-01

    Residuation Theory aims to contribute to literature in the field of ordered algebraic structures, especially on the subject of residual mappings. The book is divided into three chapters. Chapter 1 focuses on ordered sets; directed sets; semilattices; lattices; and complete lattices. Chapter 2 tackles Baer rings; Baer semigroups; Foulis semigroups; residual mappings; the notion of involution; and Boolean algebras. Chapter 3 covers residuated groupoids and semigroups; group homomorphic and isotone homomorphic Boolean images of ordered semigroups; Dubreil-Jacotin and Brouwer semigroups; and loli

  15. Comparative techno-economic analysis of steam explosion, dilute sulfuric acid, ammonia fiber explosion and biological pretreatments of corn stover.

    Science.gov (United States)

    Baral, Nawa Raj; Shah, Ajay

    2017-05-01

    Pretreatment is required to destroy recalcitrant structure of lignocelluloses and then transform into fermentable sugars. This study assessed techno-economics of steam explosion, dilute sulfuric acid, ammonia fiber explosion and biological pretreatments, and identified bottlenecks and operational targets for process improvement. Techno-economic models of these pretreatment processes for a cellulosic biorefinery of 113.5 million liters butanol per year excluding fermentation and wastewater treatment sections were developed using a modelling software-SuperPro Designer. Experimental data of the selected pretreatment processes based on corn stover were gathered from recent publications, and used for this analysis. Estimated sugar production costs ($/kg) via steam explosion, dilute sulfuric acid, ammonia fiber explosion and biological methods were 0.43, 0.42, 0.65 and 1.41, respectively. The results suggest steam explosion and sulfuric acid pretreatment methods might be good alternatives at present state of technology and other pretreatment methods require research and development efforts to be competitive with these pretreatment methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Lactic Acid Production from Pretreated Hydrolysates of Corn Stover by a Newly Developed Bacillus coagulans Strain

    OpenAIRE

    Jiang, Ting; Qiao, Hui; Zheng, Zhaojuan; Chu, Qiulu; Li, Xin; Yong, Qiang; Ouyang, Jia

    2016-01-01

    An inhibitor-tolerance strain, Bacillus coagulans GKN316, was developed through atmospheric and room temperature plasma (ARTP) mutation and evolution experiment in condensed dilute-acid hydrolysate (CDH) of corn stover. The fermentabilities of other hydrolysates with B. coagulans GKN316 and the parental strain B. coagulans NL01 were assessed. When using condensed acid-catalyzed steam-exploded hydrolysate (CASEH), condensed acid-catalyzed liquid hot water hydrolysate (CALH) and condensed acid-...

  17. High solid simultaneous saccharification and fermentation of wet oxidized corn stover to ethanol.

    Science.gov (United States)

    Varga, Enikõ; Klinke, Helene B; Réczey, Kati; Thomsen, Anne Belinda

    2004-12-05

    In this study ethanol was produced from corn stover pretreated by alkaline and acidic wet oxidation (WO) (195 degrees C, 15 min, 12 bar oxygen) followed by nonisothermal simultaneous saccharification and fermentation (SSF). In the first step of the SSF, small amounts of cellulases were added at 50 degrees C, the optimal temperature of enzymes, in order to obtain better mixing condition due to some liquefaction. In the second step more cellulases were added in combination with dried baker's yeast (Saccharomyces cerevisiae) at 30 degrees C. The phenols (0.4-0.5 g/L) and carboxylic acids (4.6-5.9 g/L) were present in the hemicellulose rich hydrolyzate at subinhibitory levels, thus no detoxification was needed prior to SSF of the whole slurry. Based on the cellulose available in the WO corn stover 83% of the theoretical ethanol yield was obtained under optimized SSF conditions. This was achieved with a substrate concentration of 12% dry matter (DM) acidic WO corn stover at 30 FPU/g DM (43.5 FPU/g cellulose) enzyme loading. Even with 20 and 15 FPU/g DM (corresponding to 29 and 22 FPU/g cellulose) enzyme loading, ethanol yields of 76 and 73%, respectively, were obtained. After 120 h of SSF the highest ethanol concentration of 52 g/L (6 vol.%) was achieved, which exceeds the technical and economical limit of the industrial-scale alcohol distillation. The SSF results showed that the cellulose in pretreated corn stover can be efficiently fermented to ethanol with up to 15% DM concentration. A further increase of substrate concentration reduced the ethanol yield significant as a result of insufficient mass transfer. It was also shown that the fermentation could be followed with an easy monitoring system based on the weight loss of the produced CO2.

  18. EFEK PERLAKUAN KIMIAWI DAN HIDROTERMOLISIS PADA BIOMAS TANAMAN JAGUNG (Zea mays L. SEBAGAI SUBSTRAT PRODUKSI BIOETANOL The Effects of Chemical and Hydrothermolysis Pretreatment of Corn Stover Biomass (Zea mays L. as The Bioethanol Production Substrate

    Directory of Open Access Journals (Sweden)

    Wagiman Wagiman

    2012-05-01

    Full Text Available The purpose of this research was to obtain a fermentation substrate with a high content of cellulose and hemicellulose, as well as to decrease the cellulose cystalinity. Dried corn stover was crushed to pass 40 mesh, added by Ca(OH and water, then heated at a certain time. The experimental design was prepared using a four-factor central composite design (CCD. The results of the chemical pretreatment were treated using hydrothermolysis methods for enhancing the lignin removal and decreasing cellulose crystalinity. The suitable process condition for chemical pretreatment was achieved at the loading of 0.075 g Ca(OH /g corn stover and 6.25 ml water/g corn stover, temperature 74.6 OC at 2 hours. After hydrothermolysis, cellulose and hemicellulose were dissolved at the percentages of 52.40 % and 31.84 % respectively, while the fraction of solid substrate had a composition of cellulose of 42.68 % and hemicellulosa of 34.68 %. The crystalinity of cellulose from the leaves, cobs, and cornhusk decreased significantly. The SEM results indicated that the surface of cell wall of corn stover had been perforated by these pretreatment processes. These pores might increase the enzymatic hydrolysis of the lignocellulosic corn stover. ABSTRAK Tujuan penelitian adalah mendapatkan substrat fermentasi dengan kandungan selulosa dan hemiselulosa tinggi serta menurunkan kristalinitas komponen selulosa. Limbah tanaman jagung yang sudah kering dihancurkan hingga lolos 40 mesh, ditambah Ca(OH dan air, kemudian dipanaskan pada suhu dan waktu tertentu. Rancangan percobaan disusun dengan menggunakan central composite design (CCD dengan empat faktor. Hasil terbaik tahap ini diberi perlakuan hidrotermolisis untuk meningkatkan penyisihan komponen lignin dan menurunkan kristalinitas selulosa. Hasil pene­ litian menunjukkan bahwa kondisi proses terbaik adalah penambahan 0,075 g Ca(OH /g biomas dan 6,25 ml air/g biomas, suhu pemanasan 74,6 OC dengan waktu 2 jam

  19. Microwave-assisted co-pyrolysis of brown coal and corn stover for oil production.

    Science.gov (United States)

    Zhang, Yaning; Fan, Liangliang; Liu, Shiyu; Zhou, Nan; Ding, Kuan; Peng, Peng; Anderson, Erik; Addy, Min; Cheng, Yanling; Liu, Yuhuan; Li, Bingxi; Snyder, John; Chen, Paul; Ruan, Roger

    2018-07-01

    The controversial synergistic effect between brown coal and biomass during co-pyrolysis deserves further investigation. This study detailed the oil production from microwave-assisted co-pyrolysis of brown coal (BC) and corn stover (CS) at different CS/BC ratios (0, 0.33, 0.50, 0.67, and 1) and pyrolysis temperatures (500, 550, and 600 °C). The results showed that a higher CS/BC ratio resulted in higher oil yield, and a higher pyrolysis temperature increased oil yield for brown coal and coal/corn mixtures. Corn stover and brown coal showed different pyrolysis characteristics, and positive synergistic effect on oil yield was observed only at CS/BC ratio of 0.33 and pyrolysis temperature of 600 °C. Oils from brown coal mainly included hydrocarbons and phenols whereas oils from corn stover and coal/corn mixtures were dominated by ketones, phenols, and aldehydes. Positive synergistic effects were observed for ketones, aldehydes, acids, and esters whereas negative synergistic effects for hydrocarbons, phenols and alcohols. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Pretreatment of corn stover with diluted acetic acid for enhancement of acidogenic fermentation.

    Science.gov (United States)

    Zhao, Xu; Wang, Lijuan; Lu, Xuebin; Zhang, Shuting

    2014-04-01

    A Box-Behnken design of response surface method was used to optimize acetic acid-catalyzed hydrothermal pretreatment of corn stover, in respect to acid concentration (0.05-0.25%), treatment time (5-15 min) and reaction temperature (180-210°C). Acidogenic fermentations with different initial pH and hydrolyzates were also measured to evaluate the optimal pretreatment conditions for maximizing acid production. The results showed that pretreatment with 0.25% acetic acid at 191°C for 7.74 min was found to be the most optimal condition for pretreatment of corn stover under which the production of acids can reach the highest level. Acidogenic fermentation with the hydrolyzate of pretreatment at the optimal condition at the initial pH=5 was shown to be butyric acid type fermentation, producing 21.84 g acetic acid, 7.246 g propionic acid, 9.170 butyric acid and 1.035 g isovaleric acid from 100g of corn stover in 900 g of water containing 2.25 g acetic acid. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Effects of thermal processing on the enzyme-linked immunosorbent assay (ELISA) detection of milk residues in a model food matrix.

    Science.gov (United States)

    Downs, Melanie L; Taylor, Steve L

    2010-09-22

    Food products and ingredients are frequently tested for the presence of undeclared allergenic food residues (including milk) using commercial enzyme-linked immunosorbent assays (ELISAs). However, little is understood about the efficacy of these kits with thermally processed foods. This study evaluated the performance of three milk ELISA kits with a model food processed by several methods. A model food (pastry dough squares) was spiked with nonfat dry milk at several concentrations. The pastry squares were processed by boiling (100 °C for 2 min), baking (190 °C for 30 min), frying (190 °C for 2 min), and retorting (121 °C for 20 min with 17 psi overpressure). Samples were analyzed with three commercial ELISA kits: Neogen Veratox Total Milk, ELISA Systems β-lactoglobulin, and ELISA Systems casein. The detection of milk residues depended upon the type of processing applied to the food and the specific milk analyte targeted by the ELISA kit. Poor recoveries were obtained in all processed samples (2-10% of expected values) using the β-lactoglobulin kit. Better recoveries were obtained in boiled samples (44 and 59%, respectively) using the total milk and casein kits. However, these kits performed poorly with baked (9 and 21%) and fried (7 and 18%) samples. Moderate recoveries were observed in retorted samples (23 and 28%). The decreased detection in processed samples is likely due to protein modifications, including aggregation and Maillard reactions, which affect the solubility and immunoreactivity of the antigens detected by the ELISA methods. The observed decreases in ELISA detection of milk are dramatic enough to affect risk-assessment decisions. However, a lower detection of milk residues does not necessarily indicate decreased allergenicity. These ELISA kits are not acceptable for all applications, and users should understand the strengths and limitations of each method.

  2. Identification and geochemical modeling of processes controlling leaching of Cr(VI) and other major elements from chromite ore processing residue

    Science.gov (United States)

    Geelhoed, Jeanine S.; Meeussen, Johannes C. L.; Hillier, Stephen; Lumsdon, David G.; Thomas, Rhodri P.; Farmer, John G.; Paterson, Edward

    2002-11-01

    Chromite ore processing residue (COPR) contains very high levels of chromium as Cr(III) and Cr(VI) and has a pH of ˜11.5 to 12. Millions of tonnes of COPR have in the past been deposited in urban areas. We have studied the factors that control leaching of Cr(VI), Ca, Al, Si, and Mg from COPR by means of batch experiments, mineralogical characterization of COPR via X-ray powder diffraction and scanning electron microscopy, and chemical equilibrium modeling. Batch experiments at a range of pH values and two liquid:solid ratios showed that mineral solubility control exists for aqueous concentrations of Cr(VI) above pH 10. Calculations indicate that the solid phases that control the solubility of Cr(VI) at pH values above 11 are Cr(VI)-substituted hydrogarnet (Ca 3Al 2(H 4O 4,CrO 4) 3) and Cr(VI)-hydrocalumite (Ca 4Al 2(OH) 12CrO 4·6 H 2O), a layered double-hydroxide clay with chromate anions held in the interlayers. In the pH range 9.5 to 11, the description of the Cr(VI) concentration in solution was strongly improved by the incorporation in the model of Cr(VI)-ettringite (Ca 6Al 2(OH) 12(CrO 4) 3·26 H 2O), which precipitates as a secondary phase when hydrocalumite dissolves. The proposed model for leaching of COPR at high pH includes Cr(VI)-bearing hydrogarnet, Cr(VI)-hydrocalumite, Cr(VI)-ettringite, brucite, calcite, Ca 2Al 2(OH) 10·3 H 2O, CaH 2SiO 4, and gehlenite hydrate (Ca 2Al 2(OH) 6SiO 8H 8·H 2O). The model accurately predicts the concentrations of Cr(VI), Ca, Al, Si, and Mg in solution in the pH range 10 to 12 as well as the pH-buffering behavior. Below pH 8, a decrease in the Cr(VI) concentration in solution is observed, which may be attributed to sorption of chromate onto freshly precipitated Al and Fe hydroxide surfaces. Sulfate and carbonate show the same type of behavior as chromate. The chemistry of COPR shows similarities with cement and high-pH municipal waste incinerator bottom ash.

  3. A Comparison of Curing Process-Induced Residual Stresses and Cure Shrinkage in Micro-Scale Composite Structures with Different Constitutive Laws

    Science.gov (United States)

    Li, Dongna; Li, Xudong; Dai, Jianfeng; Xi, Shangbin

    2018-02-01

    In this paper, three kinds of constitutive laws, elastic, "cure hardening instantaneously linear elastic (CHILE)" and viscoelastic law, are used to predict curing process-induced residual stress for the thermoset polymer composites. A multi-physics coupling finite element analysis (FEA) model implementing the proposed three approaches is established in COMSOL Multiphysics-Version 4.3b. The evolution of thermo-physical properties with temperature and degree of cure (DOC), which improved the accuracy of numerical simulations, and cure shrinkage are taken into account for the three models. Subsequently, these three proposed constitutive models are implemented respectively in a 3D micro-scale composite laminate structure. Compared the differences between these three numerical results, it indicates that big error in residual stress and cure shrinkage generates by elastic model, but the results calculated by the modified CHILE model are in excellent agreement with those estimated by the viscoelastic model.

  4. Characterization of residues of effluent treatment plant from lapping process of soda-lime glass and its application in the production of concrete

    International Nuclear Information System (INIS)

    Antonio, Aline Pignaton; Calmon, Joao Luiz; Tristao, Fernando Avancini

    2012-01-01

    This study enunciates the physical, chemical and mineralogical composition of the residue from the process of ETE cutting of soda-lime glasses and its application in concrete as a replacement to the weight of CPV ARI RS cement, at levels of 0, 5, 10, 15 and 20%. Tests were performed on fresh and hardened (ages 3, 7, 28 and 300 days). The results were compared and statistically analyzed. In the fresh state, reductions in the amount of exuding water and consistency were observed. The results of compressive strength were statistically different, while the results for the tensile strength by diametrical compression and modulus of elasticity results were belonging to homogeneous groups. Beneficial effects the levels of residue on the cementitious matrix and the transition zone of concrete were identified by SEM, particularly concrete in S15

  5. The decision-making process in dealing with populations living in areas contaminated by the uranium mining residues in Eastern Germany

    International Nuclear Information System (INIS)

    Kraus, W.; Ettenhuber, E.

    1998-01-01

    The radiological intervention situation created by uranium mining and milling residues is part of a more general problem: mining and other industrial residues with exposure to enhanced natural radiation. That part of the decision-making that should follow the principles of the radiological protection system is far from being a pre-established process. Problems are discussed that are connected with the justification and optimization of remediation measures, the establishing and meaning of action levels, as well as legal and institutional problems. They are the basis of considering the societal aspects of decision-making. The impact of public concerns on the decisions and their relation to the historic and social heritage and economic situation on the one hand, and experiences with different attempts to influence public attitudes towards radiological risks and decisions to be made on the other hand are dealt with. (author)

  6. Development of an efficient process for the treatment of residual sludge discharged from an anaerobic digester in a sewage treatment plant.

    Science.gov (United States)

    Abe, Naoki; Tang, Yue-Qin; Iwamura, Makoto; Ohta, Hiroto; Morimura, Shigeru; Kida, Kenji

    2011-09-01

    In order to reduce the discharge of residual sludge from an anaerobic digester, pre-treatment methods including low-pressure wet-oxidation, Fenton oxidation, alkali treatment, ozone oxidation, mechanical destruction and enzymatic treatment were evaluated and compared. VSS removal efficiencies of greater than 50% were achieved in cases of low-pressure wet-oxidation, Fenton oxidation and alkali treatment. Residual sludge from an anaerobic digester was pre-treated and subjected to thermophilic anaerobic digestion. As a result, the process of low-pressure wet-oxidation followed by anaerobic digestion achieved the highest VSS removal efficiency of 83%. The total efficiency of VSS removal of sewage sludge consisting of primary and surplus sludge would be approximately 92%, assuming that the VSS removal efficiency of sewage sludge is 50% in the anaerobic digester of the sewage treatment plant. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. On-farm treatment of straws and stovers with urea

    International Nuclear Information System (INIS)

    Smith, T.

    2002-01-01

    The nutritional value of cereal crop residues to ruminants is constrained by low N and high fibre contents. These constraints can be alleviated by treatment with alkali, the most suitable of which, for smallholder use, is urea. However, it has not widely been used in Africa. Whilst in some areas, cost and availability of urea will be a factor, it may also be that the flexibility of the technique is not appreciated. The scope for adaptation at each stage of the procedure is reviewed, showing that the farmer does have options to develop a system suitable for a range of conditions. (author)

  8. Validation of a method for determination of amoxicillin residues applied to cleaning validation process in penicillins pharmaceutical industry

    OpenAIRE

    Gomes, Maria Luiza Pinheiro Costa; Souza, Scheilla Vitorino Carvalho de

    2010-01-01

    The aim of this work was the single-laboratory validation of a quantitative method for the determination of amoxicillin residues in support of cleaning control and validation. Linearity was demonstrated between 2.5 and 17.5 μg/mL, without matrix effects. Mean recoveries ranged from 84.00 to 103.74% and the relative standard deviation under repetitivity and within-reproducibility conditions were from 0.58 to 4.20% and from 0.79 to 4.39%, respectively. The theoretical limits of detection a...

  9. Life cycle assessment of the production of hydrogen and transportation fuels from corn stover via fast pyrolysis

    International Nuclear Information System (INIS)

    Zhang Yanan; Brown, Robert C; Hu Guiping

    2013-01-01

    This life cycle assessment evaluates and quantifies the environmental impacts of the production of hydrogen and transportation fuels from the fast pyrolysis and upgrading of corn stover. Input data for this analysis come from Aspen Plus modeling, a GREET (Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation) model database and a US Life Cycle Inventory Database. SimaPro 7.3 software is employed to estimate the environmental impacts. The results indicate that the net fossil energy input is 0.25 MJ and 0.23 MJ per km traveled for a light-duty vehicle fueled by gasoline and diesel fuel, respectively. Bio-oil production requires the largest fossil energy input. The net global warming potential (GWP) is 0.037 kg CO 2 eq and 0.015 kg CO 2 eq per km traveled for a vehicle fueled by gasoline and diesel fuel, respectively. Vehicle operations contribute up to 33% of the total positive GWP, which is the largest greenhouse gas footprint of all the unit processes. The net GWPs in this study are 88% and 94% lower than for petroleum-based gasoline and diesel fuel (2005 baseline), respectively. Biomass transportation has the largest impact on ozone depletion among all of the unit processes. Sensitivity analysis shows that fuel economy, transportation fuel yield, bio-oil yield, and electricity consumption are the key factors that influence greenhouse gas emissions. (letter)

  10. A Five-Year Assessment of Corn Stover Harvest in Central Iowa, USA

    Energy Technology Data Exchange (ETDEWEB)

    Douglas L. Karlen; Stuart J. Birell; J. Richard Hess

    2011-11-01

    Sustainable feedstock harvest strategies are needed to ensure bioenergy production does not irreversibly degrade soil resources. The objective for this study was to document corn (Zea mays L.) grain and stover fraction yields, plant nutrient removal and replacement costs, feedstock quality, soil-test changes, and soil quality indicator response to four stover harvest strategies for continuous corn and a corn-soybean [Glycine max. (L.) Merr.] rotation. The treatments included collecting (1) all standing plant material above a stubble height of 10 cm (whole plant), (2) the upper-half by height (ear shank upward), (3) the lower-half by height (from the 10 cm stubble height to just below the earshank), or (4) no removal. Collectable biomass from Treatment 2 averaged 3.9 ({+-}0.8) Mg ha{sup -1} for continuous corn (2005 through 2009), and 4.8 ({+-}0.4) Mg ha{sup -1} for the rotated corn (2005, 2007, and 2009). Compared to harvesting only the grain, collecting stover increased the average N-P-K removal by 29, 3 and 34 kg ha{sup -1} for continuous corn and 42, 3, and 34 kg ha{sup -1} for rotated corn, respectively. Harvesting the lower-half of the corn plant (Treatment 3) required two passes, resulted in frequent plugging of the combine, and provided a feedstock with low quality for conversion to biofuel. Therefore, Treatment 3 was replaced by a 'cobs-only' harvest starting in 2009. Structural sugars glucan and xylan accounted for up to 60% of the chemical composition, while galactan, arabinan, and mannose constituted less than 5% of the harvest fractions collected from 2005 through 2008. Soil-test data from samples collected after the first harvest (2005) revealed low to very low plant-available P and K levels which reduced soybean yield in 2006 after harvesting the whole-plant in 2005. Average continuous corn yields were 21% lower than rotated yields with no significant differences due to stover harvest. Rotated corn yields in 2009 showed some significant

  11. Mathematical model parameters for describing the particle size spectra of knife-milled corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Bitra, V.S.P [University of Tennessee; Womac, A.R. [University of Tennessee; Yang, Y.T. [University of Tennessee; Miu, P.I. [University of Tennessee; Igathanathane, C. [Mississippi State University (MSU)

    2009-09-01

    Particle size distributions of Corn stover (Zea mays L.) created by a knife mill were determined using integral classifying screens with sizes from 12.7 to 50.8 mm, operating at speeds from 250 to 500 rpm, and mass input rates ranging from 1 to 9 kg min_1. Particle distributions were classified using American Society of Agricultural and Biological Engineers (ASABE) standardised sieves for forage analysis that incorporated a horizontal sieving motion. The sieves were made from machined-aluminium with their thickness proportional to the sieve opening dimensions. A wide range of analytical descriptors that could be used to mathematically represent the range of particle sizes in the distributions were examined. The correlation coefficients between geometric mean length and screen size, feed rate, and speed were 0.980, 0.612, and _0.027, respectively. Screen size and feed rate directly influenced particle size, whereas operating speed had a weak indirect relation with particle size. The Rosin Rammler equation fitted the chopped corn stover size distribution data with coefficient of determination (R2) > 0.978. This indicated that particle size distribution of corn stover was well-fit by the Rosin Rammler function. This can be attributed to the fact that Rosin Rammler expression was well suited to the skewed distribution of particle sizes. Skewed distributions occurred when significant quantities of particles, either finer or coarser, existed or were removed from region of the predominant size. The mass relative span was slightly greater than 1, which indicated that it was a borderline narrow to wide distribution of particle sizes. The uniformity coefficient was <4.0 for 19.0 50.8 mm screens, which indicated particles of relatively uniform size. Knife mill chopping of corn stover produced fine-skewed mesokurtic particles with 12.7 50.8 mm screens. Size-related parameters, namely, geometric mean length, Rosin Rammler size parameter, median length, effective length, and

  12. Compatibility of High-Moisture Storage for Biochemical Conversion of Corn Stover: Storage Performance at Laboratory and Field Scales.

    Science.gov (United States)

    Wendt, Lynn M; Murphy, J Austin; Smith, William A; Robb, Thomas; Reed, David W; Ray, Allison E; Liang, Ling; He, Qian; Sun, Ning; Hoover, Amber N; Nguyen, Quang A

    2018-01-01

    Wet anaerobic storage of corn stover can provide a year-round supply of feedstock to biorefineries meanwhile serving an active management approach to reduce the risks associated with fire loss and microbial degradation. Wet logistics systems employ particle size reduction early in the supply chain through field-chopping which removes the dependency on drying corn stover prior to baling, expands the harvest window, and diminishes the biorefinery size reduction requirements. Over two harvest years, in-field forage chopping was capable of reducing over 60% of the corn stover to a particle size of 6 mm or less. Aerobic and anaerobic storage methods were evaluated for wet corn stover in 100 L laboratory reactors. Of the methods evaluated, traditional ensiling resulted in benefits for commercial corn stover supply, including particle size reduction during harvest, stability in storage, and compatibility with biochemical conversion of carbohydrates for biofuel production. Evaluation of the operational efficiencies and costs is suggested to quantify the potential benefits of a fully-wet biomass supply system to a commercial biorefinery.

  13. Disposal of residue from uranium ore processing in France; Les stockages de residus de traitement de minerais d'uranium en France

    Energy Technology Data Exchange (ETDEWEB)

    Crochon, Ph. [AREVA NC, Business Group Mines, Dir. de la responsabilite environnementale et societale, 75 -Paris (France)

    2011-02-15

    Between 1949 and 2001, French mines produced 76, 000 metric tons of uranium and 50 million metric tons of ore, processing residues are stored at 17 sites (in ponds enclosed by dykes or in former open-cast mines) subject to ICPE (classified facility for environment protection) regulation. These disposal sites cover surface areas of between one and several tens of hectares and several thousands to several millions of metric tons of waste are stored at them. When uranium mining stopped in France, these sites were redeveloped, with caps placed over the residue to provide mechanical and radiological protection. All these sites are still monitored by AREVA. In the last fifteen years, these sites have been the subject of a number of studies, especially regarding the long-term evolution and impact of the residue. These studies are now being pursued within the framework of the national plan for the management of nuclear materials and waste (PNGMDR). A regulatory and institutional framework regarding long-term management of these disposal sites needs to be defined. (author)

  14. Pyrolysis thermocatalytic of the residues generated in the process of oil refining; Pirolise termocatalitica de residuos gerados no processo de refino de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Regineide Oliveira; Castro, Kesia Kelly Vieira de; Lima, Cicero de Souza; Araujo, Aruzza Mabel de Morais; Silva, Edjane Fabiula Buriti da; Araujo, Antonio Souza de [Universidade Federal do Rio Grande do Norte (UFRN), RN (Brazil)

    2012-07-01

    The pyrolysis process is a catalytic thermal defined as the degradation of waste which occurs by the action of temperature and presence of catalysts. Thus promoting disruption of the original molecular structure of a given compound by the catalytic action in an environment with little or no oxygen. Investigations have been developed in the pyrolysis due to be a promising technique, due to the application of catalytic materials. In this work, the catalyst used Al/MCM-41 was synthesized in a ratio Si / Al = 50 by the hydrothermal method. Being in this promising oil industry because of their structural characteristics. This material was characterized by XRD analysis, which was observed three major peaks typical of mesoporous materials. The analysis of the adsorption / desorption of nitrogen this material was performed to determine the textural parameters, which are peculiar to the mesoporous materials. The residue samples were characterized with a view to meet some properties such as through elemental analysis of the compounds and saturates, aromatics, resins and asphaltenes. The pyrolysis reaction system catalytic thermal residue is mounted to test the pyrolysis of residue pure and the Al-MCM-41. For both pyrolysis liquid fractions were obtained, gaseous and solid. And only the liquid fractions were characterized by chromatography coupled to mass spectrometry. Thus, there was an increase in the range hydrocarbons (C6-C12 and C13-C17) for products obtained from the pyrolysis catalyst. (author)

  15. Three-way principal component analysis as a tool to evaluate the chemical stability of metal bearing residues from wastewater treatment by the ferrite process

    International Nuclear Information System (INIS)

    Pardo, Rafael; Vega, Marisol; Barrado, Enrique; Castrillejo, Yolanda; Sánchez, Isabel

    2013-01-01

    Highlights: • Metal fractionation of residues from the ferrite process was investigated by n-way PCA. • BCR sequential extraction procedure used for metal fractionation. • Tucker3 algorithm originated a coherent two-term trilinear model. • Metal fractionation patterns correlate with magnetic character of solids. -- Abstract: The chemical fractionation patterns of eight metals (Cd, Co, Cu, Cr, Mn, Ni, Pb and Zn) have been determined in 27 metal-bearing residues by using the BCR sequential extraction procedure. The residues were generated as by-products during the optimization of a semi-continuous reactor for metal removal from wastewater based on ferrite synthesis by co-precipitation. The three-dimensional X dataset (samples × metals × fractions) obtained by applying the BCR procedure has been analyzed by multivariate methods: matrix augmentation (MA-PCA) and three-way principal component analysis, 3-PCA (PARAFAC and Tucker3 models). MA-PCA and PARAFAC methods led to two-factor models giving a satisfactory but incomplete picture of the metal fractionation patterns, but the Tucker3 [2,1,2] model allowed to simultaneously describe both the ‘pseudo-total’ (acid-soluble) contents and the chemical fractionation by means of two non-null interactions g 111 and g 212 which explain 53.5% and 18.0% of the total variance, respectively. The A-mode loadings of the g 212 interaction showed the close relationship between the magnetic character of the solid residues, i.e. the crystalline structure, and the chemical fractionation patterns of the metals resulting from the application of the BCR sequential extraction procedure

  16. Modeling of pretreatment condition of extrusion-pretreated prairie cordgrass and corn stover with poly (oxyethylen)20 sorbitan monolaurate.

    Science.gov (United States)

    Eckard, Anahita Dehkhoda; Muthukumarappan, Kasiviswanathan; Gibbons, William

    2012-05-01

    Extrusion processing has shown potential to be used as a pretreatment method for second-generation bioethanol production. Furthermore, surfactants have been shown to reduce enzyme deactivation and increase the efficiency of hydrolysis. Therefore, a sequential pretreatment technique was developed for corn stover (CS) and prairie cordgrass (PCG) in which a single screw extruder was used for the first pretreatment according to a previously optimized condition using 70-180 °C for feed, barrel, and die zones with 65-155 rpm screw speed. The second pretreatment was optimized in this study at 45-55 °C, 1-4 h, 0.15-0.6 g Tween 20/g glucan according to response surface methodology. Optimization of surfactant pretreatment facilitated the estimation of interaction and higher-order effects for major factors involved in surfactant treatment (temperature, time, surfactant loading). Using 8.6 FPU/g glucan cellulase, the optimum conditions found by fitting appropriate quadratic models to the data increased glucose and xylose yield by 27.5 and 33% for CS and by 21.5 and 27% for PCG, respectively. Tween 20 concentrations and pretreatment temperature were the most significant factors affecting sugar yield (p value <0.05). Studies of SDS concentration at and beyond critical micelle concentration (5.2-100 mM) demonstrated a decrease in sugar yield compared to control.

  17. Finite Element Analysis of Residual Stress in Ti-6Al-4V Alloy Plate Induced by Deep Rolling Process under Complex Roller Path

    Directory of Open Access Journals (Sweden)

    J. J. Liou

    2014-01-01

    Full Text Available The kinematics of the deep rolling tool, contact stress, and induced residual stress in the near-surface material of a flat Ti-6Al-4V alloy plate are numerically investigated. The deep rolling tool is under multiaxis nonlinear motion in the process. Unlike available deep rolling simulations in the open literature, the roller motion investigated in this study includes penetrative and slightly translational motions. A three-dimensional finite element model with dynamic explicit technique is developed to simulate the instantaneous complex roller motions during the deep rolling process. The initial motion of the rollers followed by the penetration motion to apply the load and perform the deep rolling process, the load releasing, and material recovery steps is sequentially simulated. This model is able to capture the transient characteristics of the kinematics on the roller and contacts between the roller and the plate due to variations of roller motion. The predictions show that the magnitude of roller reaction force in the penetration direction starts to decrease with time when the roller motion changes to the deep rolling step and the residual stress distributions in the near-surface material after the material recovery step varies considerably along the roller path.

  18. Modeling of the fatigue damage accumulation processes in the material of NPP design units under thermomechanical unstationary effects. Estimation of spent life and forecast of residual life

    International Nuclear Information System (INIS)

    Kiriushin, A.I.; Korotkikh, Yu.G.; Gorodov, G.F.

    2002-01-01

    Full text: The estimation problems of spent life and forecast of residual life of NPP equipment design units, operated at unstationary thermal force loads are considered. These loads are, as a rule, unregular and cause rotation of main stress tensor platforms of the most loaded zones of structural elements and viscoelastic plastic deformation of material in the places of stresses concentrations. The existing engineering approaches to the damages accumulation processes calculation in the material of structural units, their advantages and disadvantages are analyzed. For the processes of fatigue damages accumulation a model is proposed, which allows to take into account the unregular pattern of deformation multiaxiality of stressed state, rotation of main platforms, non-linear summation of damages at the loading mode change. The model in based on the equations of damaged medium mechanics, including the equations of viscoplastic deformation of the material and evolutionary equations of damages accumulation. The algorithms of spent life estimation and residual life forecast of the controlled equipment and systems zones are made on the bases of the given model by the known real history of loading, which is determined by real model of NPP operation. The results of numerical experiments on the basis of given model for various processes of thermal force loads and their comparison with experimental results are presented. (author)

  19. Degradation of corn stover by fungal cellulase cocktail for production of polyhydroxyalkanoates by moderate halophile Paracoccus sp. LL1.

    Science.gov (United States)

    Sawant, Shailesh S; Salunke, Bipinchandra K; Kim, Beom Soo

    2015-10-01

    Bioprocessing of lignocellulose as a renewable resource for fuels, chemicals or value added products is a necessity to fulfil demands of petroleum products. This study aims to convert corn stover to polyhydroxyalkanoates (PHA). Corn stover was hydrolyzed to crude sugars by an on-site prepared cellulase cocktail from co-culture of Trichoderma reesei and Aspergillus niger. The potent PHA producer, Paracoccus sp. LL1, was isolated from Lonar Lake, India and could accumulate PHA up to 72.4% of its dry cell weight. PHA production reached 9.71 g/L from corn stover hydrolysate containing 40 g/L sugar mixture. The PHA synthase gene (phaC) sequence of the isolate showed 79% identity with the phaC gene of Paracoccus seriniphilus (E71) strain from the NCBI database. The nature/type of PHA was found to be poly(3-hydroxybutyrate) by Fourier transform infrared spectroscopy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Simultaneous saccharification and co-fermentation of aqueous ammonia pretreated corn stover with an engineered Saccharomyces cerevisiae SyBE005.

    Science.gov (United States)

    Zhu, Jia-Qing; Qin, Lei; Li, Bing-Zhi; Yuan, Ying-Jin

    2014-10-01

    Co-fermentation of glucose and xylose from lignocelluloses is an efficient approach to increasing ethanol production. Simultaneous saccharification and co-fermentation (SSCF) of corn stover pretreated with aqueous ammonia was performed using engineered yeast with xylose utilization pathway. Thus far, the effect of the several key factors on SSCF was investigated, including temperature, inoculation size, pre-hydrolysis and pH. Ethanol concentration was achieved to 36.5 g/L during SSCF process with 6% glucan loading. The addition of Tween 20 reduced enzyme loading, i.e., from 15 to 7.5 FPU/gglucan with the same final ethanol concentration. The ethanol concentration was achieved to 70.1g/L at 12% glucan loading. Yeast feeding, combined with substrate and enzyme feeding, was proved to be an efficient approach for SSCF with high solid loading. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Handling of Solid Residues

    International Nuclear Information System (INIS)

    Medina Bermudez, Clara Ines

    1999-01-01

    The topic of solid residues is specifically of great interest and concern for the authorities, institutions and community that identify in them a true threat against the human health and the atmosphere in the related with the aesthetic deterioration of the urban centers and of the natural landscape; in the proliferation of vectorial transmitters of illnesses and the effect on the biodiversity. Inside the wide spectrum of topics that they keep relationship with the environmental protection, the inadequate handling of solid residues and residues dangerous squatter an important line in the definition of political and practical environmentally sustainable. The industrial development and the population's growth have originated a continuous increase in the production of solid residues; of equal it forms, their composition day after day is more heterogeneous. The base for the good handling includes the appropriate intervention of the different stages of an integral administration of residues, which include the separation in the source, the gathering, the handling, the use, treatment, final disposition and the institutional organization of the administration. The topic of the dangerous residues generates more expectation. These residues understand from those of pathogen type that are generated in the establishments of health that of hospital attention, until those of combustible, inflammable type, explosive, radio-active, volatile, corrosive, reagent or toxic, associated to numerous industrial processes, common in our countries in development

  2. Outdoor Storage Characteristics of Single-Pass Large Square Corn Stover Bales in Iowa

    Directory of Open Access Journals (Sweden)

    Ajay Shah

    2011-10-01

    Full Text Available Year-round operation of biorefineries can be possible only if the continuous flow of cellulosic biomass is guaranteed. If corn (Zea mays stover is the primary cellulosic biomass, it is essential to recognize that this feedstock has a short annual harvest window (≤1–2 months and therefore cost effective storage techniques that preserve feedstock quality must be identified. This study evaluated two outdoor and one indoor storage strategies for corn stover bales in Iowa. High- and low-moisture stover bales were prepared in the fall of 2009, and stored either outdoors with two different types of cover (tarp and breathable film or within a building for 3 or 9 months. Dry matter loss (DML, changes in moisture and biomass compositions (fiber and ultimate analyses were determined. DML for bales stored outdoor with tarp and breathable film covers were in the ranges of 5–11 and 14–17%, respectively. More than half of the total DML occurred early during the storage. There were measurable differences in carbon, hydrogen, nitrogen, sulfur, oxygen, cellulose, hemi-cellulose and acid detergent lignin for the different storage treatments, but the changes were small and within a narrow range. For the bale storage treatments investigated, cellulose content increased by as much as 4%s from an initial level of ~41%, hemicellulose content changed by −2 to 1% from ~34%, and acid detergent lignin contents increased by as much as 3% from an initial value of ~5%. Tarp covered bales stored the best in this study, but other methods, such as tube-wrapping, and economics need further investigation.

  3. Electroleaching for a decontamination of mercury polluted soils and residues. Development of a hydrometallurgical cyclic process; Elektrolaugung zur Dekontamination quecksilberbelasteter Boeden und Reststoffe. Entwicklung eines hydrometallurgischen Kreislaufprozesses

    Energy Technology Data Exchange (ETDEWEB)

    Thoeming, J. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Zentralabteilung Technikum

    1998-12-31

    In this thesis, the possibilities and limitations of a hydrometallurgical clean-up technique are shown for treating mercury contaminated solids. The principles of the technique were described by models that derived from theoretical considerations. These models were experimentally examined, tested with realcontaminated solids and used to design a new process, the electroleaching. Two variants of this cyclic process were developed. They differ in the combination of a chloridic oxidative leaching step, a cathodic mercury deposition and an anodic leachate regeneration. All steps were analysed thermodynamically and kinetically. Treating highly contaminated soils residual concentrations of mercury below 1 mg kg{sup -1} were achieved. It was also possible to separate simultaneously traces of gold from mercury containing gold mining residues and to lower contents of chlorinated hydrocarbons a well. (orig.) [Deutsch] In dieser Arbeit werden die Moeglichkeiten und Grenzen einer hydrometallurgischen Reinigungstechnik fuer Feststoffe aufgezeigt, die mit Quecksilber kontaminiert sind. Dazu wurden aus theoretischen Ueberlegungen heraus entwickelte Modellierungen experimentell abgeprueft, verfahrenstechnisch umgesetzt und an realkontaminierten Feststoffen erprobt. So wurde ein neues Kreislaufverfahren entwickelt, die Elektrolaugung. Die zwei vorgestellten Prozessvarianten unterscheiden sich durch die jeweilige Kombination von chloridisch-oxidierender Laugung, kathodischer Quecksilberabscheidung und anodischer Laugungsmittel-Regenerierung. Alle Teilprozesse wurden sowohl thermodynamisch als auch kinetisch analysiert. Bei Behandlung industrieller Altlasten konnten Quecksilber-Restgehalte unter 1 mg kg{sup -1} erreicht werden. Ebenso konnten Goldspuren aus quecksilberhaltigen Abgaengen brasilianischer Goldgewinnung abgetrennt sowie Gehalte an chlorierten Kohlenwasserstoffen verringert werden. (orig.)

  4. Life-cycle greenhouse gas emission and energy use of bioethanol produced from corn stover in China: Current perspectives and future prospectives

    International Nuclear Information System (INIS)

    Zhao, Lili; Ou, Xunmin; Chang, Shiyan

    2016-01-01

    In this study, a life cycle analysis (LCA) of bioethanol production from corn stover is carried out under Chinese context. Three scenarios were developed and assessed based on current and future technology levels of the ethanol conversion process. Well-to-pump (WTP) and well-to-wheels (WTW) results are presented in this paper via functional units of 1 MJ of ethanol produced, 1 MJ of E100 produced and used, and 1 km of distance driven by a light-duty vehicle on E10 fuel, respectively. It was calculated that for 1 MJ of E100, the WTW Greenhouse gas (GHG) emission reduction relative to gasoline reaches 52%–55%, and the savings of fossil fuel and petroleum fuel reach 72%–76% and 74%–85%, respectively. For 1 MJ of ethanol produced, GHG emissions occurred in ethanol conversion process account for 51%–55%, and the contribution of chemical inputs reaches 36%–37% of the total life cycle GHG emissions. Furthermore, the life cycle results were found to be highly sensitive to allocation methods. - Highlights: • The study is focused on 2 G bioethanol derived from corn stover in Chinese context. • LCA is based on both current and future technology levels for ethanol conversion. • The life cycle GHG emission reduction of E100 relative to gasoline reaches 52%–55%. • Contributions of chemicals account for 36%–37% of life cycle GHG emissions. • E100 saves 74%–85% of petroleum fuel during its life cycle production and use.

  5. The Impact of Enzyme Characteristics on Corn Stover Fiber Degradation and Acid Production During Ensiled Storage

    Science.gov (United States)

    Ren, Haiyu; Richard, Tom L.; Moore, Kenneth J.

    Ensilage can be used to store lignocellulosic biomass before industrial bioprocessing. This study investigated the impacts of seven commerical enzyme mixtures derived from Aspergillus niger, Trichoderma reesei, and T. longibrachiatum. Treatments included three size grades of corn stover, two enzyme levels (1.67 and 5 IU/g dry matter based on hemicellulase), and various ratios of cellulase to hemicellulase (C ∶ H). The highest C ∶ H ratio tested, 2.38, derived from T. reesei, resulted in the most effective fermentation, with lactic acid as the dominant product. Enzymatic activity during storage may complement industrial pretreatment; creating synergies that could reduce total bioconversion costs.

  6. Systematics of corn stover pyrolysis yields and comparisons of analytical and kinetic representations

    Energy Technology Data Exchange (ETDEWEB)

    Green, Alex E.S. [Clean Combustion Technology Laboratory, University of Florida, Gainesville, FL 32611-6550 (United States); Feng, Jie [Key Laboratory of Coal Science and Technology, Taiyuan University of Technology, Taiyuan, Shanxi 030024 (China)

    2006-06-01

    This paper focuses on the systematics of a large body of experimental corn stover pyrolysis yields measured with a Pyroprobe-FTIR system at Taiyuan University of Technology (TUT) using a wide range of heating rates, This large body of data is organized using an analytical semi-empirical model (ASEM) developed at the University of Florida that provides a reasonable account using only a small number of adjusted parameters. The data is also organized with a traditional kinetic model (Arrhenius reaction rates) and comparisons are made between the two models from the viewpoint of engineering applications of pyrolysis. (author)

  7. Herpes Simplex Virus Type 1 Glycoprotein B Requires a Cysteine Residue at Position 633 for Folding, Processing, and Incorporation into Mature Infectious Virus Particles

    Science.gov (United States)

    Laquerre, Sylvie; Anderson, Dina B.; Argnani, Rafaela; Glorioso, Joseph C.

    1998-01-01

    Herpes simplex virus type 1 (HSV-1) glycoprotein B (gB) resides in the virus envelope in an oligomeric form and plays an essential role in virus entry into susceptible host cells. The oligomerizing domain is a movable element consisting of amino acids 626 to 653 in the gB external domain. This domain contains a single cysteine residue at position 633 (Cys-633) that is predicted to form an intramolecular disulfide bridge with Cys-596. In this study, we examined gB oligomerization, processing, and incorporation into mature virus during infection by two mutant viruses in which either the gB Cys-633 [KgB(C633S)] or both Cys-633 and Cys-596 [KgB(C596S/C633S)] residues were mutated to serine. The result of immunofluorescence studies and analyses of released virus particles showed that the mutant gB molecules were not transported to the cell surface or incorporated into mature virus envelopes and thus infectious virus was not produced. Immunoprecipitation studies revealed that the mutant gB molecules were in an oligomeric configuration and that these mutants produced hetero-oligomers with a truncated form of gB consisting of residues 1 to 43 and 595 to 904, the latter containing the oligomerization domain. Pulse-chase experiments in combination with endoglycosidase H treatment determined that the mutant molecules were improperly processed, having been retained in the endoplasmic reticulum (ER). Coimmunoprecipitation experiments revealed that the cysteine mutations resulted in gB misfolding and retention by the molecular chaperones calnexin, calreticulin, and Grp78 in the ER. The altered conformation of the gB mutant glycoproteins was directly detected by a reduction in monoclonal antibody recognition of two previously defined distinct antigenic sites located within residues 381 to 441 and 595 to 737. The misfolded molecules were not transported to the cell surface as hetero-oligomers with wild-type gB, suggesting that the conformational change could not be corrected by

  8. Soy Sauce Residue Oil Extracted by a Novel Continuous Phase Transition Extraction under Low Temperature and Its Refining Process.

    Science.gov (United States)

    Zhao, Lichao; Zhang, Yong; He, Liping; Dai, Weijie; Lai, Yingyi; Yao, Xueyi; Cao, Yong

    2014-04-09

    On the basis of previous single-factor experiments, extraction parameters of soy sauce residue (SSR) oil extracted using a self-developed continuous phase transition extraction method at low temperature was optimized using the response surface methodology. The established optimal conditions for maximum oil yield were n-butane solvent, 0.5 MPa extraction pressure, 45 °C temperature, 62 min extraction time, and 45 mesh raw material granularity. Under these conditions, the actual yield was 28.43% ± 0.17%, which is relatively close to the predicted yield. Meanwhile, isoflavone was extracted from defatted SSR using the same method, but the parameters and solvent used were altered. The new solvent was 95% (v/v) ethanol, and extraction was performed under 1.0 MPa at 60 °C for 90 min. The extracted isoflavones, with 0.18% ± 0.012% yield, mainly comprised daidzein and genistein, two kinds of aglycones. The novel continuous phase transition extraction under low temperature could provide favorable conditions for the extraction of nonpolar or strongly polar substances. The oil physicochemical properties and fatty acids compositions were analyzed. Results showed that the main drawback of the crude oil was the excess of acid value (AV, 63.9 ± 0.1 mg KOH/g) and peroxide value (POV, 9.05 ± 0.3 mmol/kg), compared with that of normal soybean oil. However, through molecular distillation, AV and POV dropped to 1.78 ± 0.12 mg KOH/g and 5.9 ± 0.08 mmol/kg, respectively. This refined oil may be used as feedstuff oil.

  9. Thermodynamic study of residual heat from a high temperature nuclear reactor to analyze its viability in cogeneration processes

    International Nuclear Information System (INIS)

    Santillan R, A.; Valle H, J.; Escalante, J. A.

    2015-09-01

    In this paper the thermodynamic study of a nuclear power plant of high temperature at gas turbine (GTHTR300) is presented for estimating the exploitable waste heat in a process of desalination of seawater. One of the most studied and viable sustainable energy for the production of electricity, without the emission of greenhouse gases, is the nuclear energy. The fourth generation nuclear power plants have greater advantages than those currently installed plants; these advantages have to do with security, increased efficiencies and feasibility to be coupled to electrical cogeneration processes. In this paper the thermodynamic study of a nuclear power plant type GTHTR300 is realized, which is selected by greater efficiencies and have optimal conditions for use in electrical cogeneration processes due to high operating temperatures, which are between 700 and 950 degrees Celsius. The aim of the study is to determine the heat losses and the work done at each stage of the system, determining where they are the greatest losses and analyzing in that processes can be taken advantage. Based on the study was appointed that most of the energy losses are in form of heat in the coolers and usually this is emitted into the atmosphere without being used. From the results a process of desalination of seawater as electrical cogeneration process is proposed. This paper contains a brief description of the operation of the nuclear power plant, focusing on operation conditions and thermodynamic characteristics for the implementation of electrical cogeneration process, a thermodynamic analysis based on mass and energy balance was developed. The results allow quantifying the losses of thermal energy and determining the optimal section for coupling of the reactor with the desalination process, seeking to have a great overall efficiency. (Author)

  10. Treatment of biological waste and residues V. Biological - mechanical - thermal processes; Bio- und Restabfallbehandlung V. Biologisch - mechanisch - thermisch

    Energy Technology Data Exchange (ETDEWEB)

    Wiemer, K.; Kern, M. (eds.); Weber-Wied, R. (comp.)

    2001-07-01

    From 2005, the TA Siedlungsabfall (Waste Management Regulation) will come into force, and European legislation will overrule national legislation. Dumping of untreated waste in landfills will be prohibited, i.e. incinerators for thermal waste treatment must be constructed. In view of the rigid specifications for emissions and residues and the demand for Europe-wide invitations for tender, time is running short. The book outlines the options for action of the German states and of some applicant states for EC membership. The German government already issued an Ordinance for Power Generation from Biomass. Independent of this, also secondary fuels are gaining ground, and several contributions of the conference discussed quality assurance and utilization of secondary fuels. Composting and sewage sludge utilization are further current issues. Air pollution, soil and groundwater protection, job security and energy potential are gone into, and an outline of the current situation of waste management is attempted. [German] Die aktuelle abfallwirtschaftliche Situation wird in besonderem Masse gepraegt durch das nahende Jahr 2005 sowie die zunehmende Abhaengigkeit nationalstaatlicher Handlungsspielraeume von den Vorgaben europaeischer Rahmenrichtlinien. Hierbei wird der Handlungsdruck spuerbar, spaetestens ab dem Jahr 2005 der TA Siedlungsabfall Rechnung tragen zu muessen. Die verbleibenden Zeitraeume sind daher eng bemessen, beruecksichtigt man insbesondere die langen Genehmigungs- und Errichtungszeitraeume fuer thermische Behandlungsanlagen. Vor dem Hintergrund der europaweiten Ausschreibungspflicht wird die gegenwaertige technische Diskussion zur MBA sehr stark durch die nunmehr von der Bundesregierung konkretisierten Emissions- und Ablagerungsanforderungen gepraegt. Der vorliegende Band soll aufzeigen, welche Handlungsspielraeume sich hierbei aus Sicht der verschiedenen Bundeslaender ergeben. Ein Blick ueber die Grenzen hinaus zu einigen zukuenftigen EU

  11. Effect of clarification process on the removal of pesticide residues in red wine and comparison with white wine.

    Science.gov (United States)

    Doulia, Danae S; Anagnos, Efstathios K; Liapis, Konstantinos S; Klimentzos, Demetrios A

    2018-04-30

    The aim of this study was to determine the potential of seven clarifying agents to remove pesticides in red wine. The presence of pesticides in wine consists a great problem for winemakers and therefore, results on pesticide removal by clarification are very useful for taking a decision on the appropriate adsorbent. The selection of an efficient adsorbent can be based on data correlating pesticide removal in red wine to pesticides' properties, given the great number and variety of pesticides used. So, this experimental work is focused on the collection of results with regard to pesticide removal by clarification using a great number of pesticides and fining agents. A Greek red wine, fortified with single solutions and mixtures of 23 or 9 pesticides was studied. The seven fining agents, used at two concentrations, were activated carbon, bentonite, polyvinylpolypyrrolidone (PVPP), gelatin, egg albumin, isinglass-fish glue, and casein. Pesticides were selected with a wide range of properties (octanol-water partition coefficient (log K ow ) 2.7-6.3 and water solubility 0.0002-142) and belong to 11 chemical groups. Solid phase extraction (SPE) followed by gas chromatography (GC) with electron capture detector (ECD) were performed to analyze pesticide residues of the clarified fortified wine. The correlation of the clarifying agents' effectiveness to pesticide's chemical structure and properties (log K ow , water solubility) was investigated. The antagonistic and/or synergistic effects, occurring among the pesticides in the mixtures, were calculated by indices. Pesticide removal effectiveness results of the red wine were compared to those obtained from a white wine under the same experimental conditions and discussed. The order of decreasing adsorbent effectiveness (mixture of 23 pesticides) was: activated carbon 40% > gelatin 23% > egg albumin 21% > PVPP 18% > casein 12% > bentonite 7%. Isinglass showed 12% removal at the highest permitted concentration. In the case of

  12. Residual risk

    African Journals Online (AJOL)

    ing the residual risk of transmission of HIV by blood transfusion. An epidemiological approach assumed that all HIV infections detected serologically in first-time donors were pre-existing or prevalent infections, and that all infections detected in repeat blood donors were new or incident infections. During 1986 - 1987,0,012%.

  13. Behaviour and dynamics of di-ammonium phosphate in bauxite processing residue sand in Western Australia--II. Phosphorus fractions and availability.

    Science.gov (United States)

    Chen, C R; Phillips, I R; Wei, L L; Xu, Z H

    2010-06-01

    The production of alumina involves its extraction from bauxite ore using sodium hydroxide under high temperature and pressure. This process yields a large amount of residue wastes, which are difficult to revegetate due to their inherent hostile properties--high alkalinity and sodicity, poor water retention and low nutrient availability. Although phosphorus (P) is a key element limiting successful ecosystem restoration, little information is available on the availability and dynamics of P in rehabilitated bauxite-processing residue sand (BRS). The major aim of this experiment was to quantify P availability and behaviour as affected by pH, source of BRS and di-ammonium phosphate (DAP) application rate. This incubation experiment was undertaken using three sources of BRS, three DAP application rates (low, without addition of DAP; medium, 15.07 mg P and 13.63 mg N of DAP per jar, 100 g BRS; and high, 30.15 mg P and 27.26 mg N per jar, 100 g BRS), and four BRS pH treatments (4, 7, 9 and 11 (original)). The moisture content was adjusted to 55% water holding capacity and each BRS sample was incubated at 25 degrees C for a period of 119 days. After this period, Colwell P and 0.1 M H(2)SO(4) extractable P in BRS were determined. In addition, P sequential fractionation was carried out and the concentration of P in each pool was measured. A significant proportion (37% recovered in Colwell P and 48% in 0.1 M H(2)SO(4) extraction) of P added as DAP in BRS are available for plant use. The pH did not significantly affect 0.1 M H(2)SO(4) extractable P, while concentrations of Colwell P in the higher initial pH treatments (pH 7, 9 and 11) were greater than in the pH 4 treatments. The labile fractions (sum of NH(4)Cl (AP), bicarbonate and first sodium hydroxide extractable P (N(I)P)) consisted of 58-64% and 70-72% of total P in the medium and high DAP rate treatments, respectively. This indicates that most P added as DAP remained labile or moderately labile in BRS, either in

  14. Effect of mechanical disruption on the effectiveness of three reactors used for dilute acid pretreatment of corn stover Part 1: chemical and physical substrate analysis.

    Science.gov (United States)

    Wang, Wei; Chen, Xiaowen; Donohoe, Bryon S; Ciesielski, Peter N; Katahira, Rui; Kuhn, Erik M; Kafle, Kabindra; Lee, Christopher M; Park, Sunkyu; Kim, Seong H; Tucker, Melvin P; Himmel, Michael E; Johnson, David K

    2014-01-01

    There is considerable interest in the conversion of lignocellulosic biomass to liquid fuels to provide substitutes for fossil fuels. Pretreatments, conducted to reduce biomass recalcitrance, usually remove at least some of the hemicellulose and/or lignin in cell walls. The hypothesis that led to this research was that reactor type could have a profound effect on the properties of pretreated materials and impact subsequent cellulose hydrolysis. Corn stover was dilute-acid pretreated using commercially relevant reactor types (ZipperClave(®) (ZC), Steam Gun (SG) and Horizontal Screw (HS)) under the same nominal conditions. Samples produced in the SG and HS achieved much higher cellulose digestibilities (88% and 95%, respectively), compared to the ZC sample (68%). Characterization, by chemical, physical, spectroscopic and electron microscopy methods, was used to gain an understanding of the effects causing the digestibility differences. Chemical differences were small; however, particle size differences appeared significant. Sum-frequency generation vibrational spectra indicated larger inter-fibrillar spacing or randomization of cellulose microfibrils in the HS sample. Simons' staining indicated increased cellulose accessibility for the SG and HS samples. Electron microscopy showed that the SG and HS samples were more porous and fibrillated because of mechanical grinding and explosive depressurization occurring with these two reactors. These structural changes most likely permitted increased cellulose accessibility to enzymes, enhancing saccharification. Dilute-acid pretreatment of corn stover using three different reactors under the same nominal conditions gave samples with very different digestibilities, although chemical differences in the pretreated substrates were small. The results of the physical and chemical analyses of the samples indicate that the explosive depressurization and mechanical grinding with these reactors increased enzyme accessibility

  15. Effect of mechanical disruption on the effectiveness of three reactors used for dilute acid pretreatment of corn stover Part 1: chemical and physical substrate analysis

    Science.gov (United States)

    2014-01-01

    Background There is considerable interest in the conversion of lignocellulosic biomass to liquid fuels to provide substitutes for fossil fuels. Pretreatments, conducted to reduce biomass recalcitrance, usually remove at least some of the hemicellulose and/or lignin in cell walls. The hypothesis that led to this research was that reactor type could have a profound effect on the properties of pretreated materials and impact subsequent cellulose hydrolysis. Results Corn stover was dilute-acid pretreated using commercially relevant reactor types (ZipperClave® (ZC), Steam Gun (SG) and Horizontal Screw (HS)) under the same nominal conditions. Samples produced in the SG and HS achieved much higher cellulose digestibilities (88% and 95%, respectively), compared to the ZC sample (68%). Characterization, by chemical, physical, spectroscopic and electron microscopy methods, was used to gain an understanding of the effects causing the digestibility differences. Chemical differences were small; however, particle size differences appeared significant. Sum-frequency generation vibrational spectra indicated larger inter-fibrillar spacing or randomization of cellulose microfibrils in the HS sample. Simons’ staining indicated increased cellulose accessibility for the SG and HS samples. Electron microscopy showed that the SG and HS samples were more porous and fibrillated because of mechanical grinding and explosive depressurization occurring with these two reactors. These structural changes most likely permitted increased cellulose accessibility to enzymes, enhancing saccharification. Conclusions Dilute-acid pretreatment of corn stover using three different reactors under the same nominal conditions gave samples with very different digestibilities, although chemical differences in the pretreated substrates were small. The results of the physical and chemical analyses of the samples indicate that the explosive depressurization and mechanical grinding with these reactors increased

  16. A chemically enhanced biological process for lowering operative costs and solid residues of industrial recalcitrant wastewater treatment.

    Science.gov (United States)

    Di Iaconi, Claudio; Del Moro, Guido; De Sanctis, Marco; Rossetti, Simona

    2010-06-01

    An innovative process based on ozone-enhanced biological degradation, carried out in an aerobic granular biomass system (SBBGR--Sequencing Batch Biofilter Granular Reactor), was tested at pilot scale for tannery wastewater treatment chosen as representative of industrial recalcitrant wastewater. The results have shown that the process was able to meet the current discharge limits when the biologically treated wastewater was recirculated through an adjacent reactor where a specific ozone dose of 120 mg O3/L(influent) was used. The benefits produced by using ozone were appreciable even visually since the final effluent of the process looked like tap water. In comparison with the conventional treatment, the proposed process was able to reduce the sludge production by 25-30 times and to save 60% of operating costs. Molecular in situ detection methods were employed in combination with the traditional measurements (oxygen uptake rate, total protein content, extracellular polymeric substances and hydrophobicity) to evaluate microbial activity and composition, and the structure of the biomass. A stable presence of active bacterial populations was observed in the biomass with the simultaneous occurrence of distinctive functional microbial groups involved in carbon, nitrogen and sulphate removal under different reaction environments established within the large microbial aggregates. The structure and activity of the biomass were not affected by the use of ozone. 2010 Elsevier Ltd. All rights reserved.

  17. Effect of leaching residual methyl methacrylate concentrations on in vitro cytotoxicity of heat polymerized denture base acrylic resin processed with different polymerization cycles.

    Science.gov (United States)

    Bural, Canan; Aktaş, Esin; Deniz, Günnur; Ünlüçerçi, Yeşim; Bayraktar, Gülsen

    2011-08-01

    Residual methyl methacrylate (MMA) may leach from the acrylic resin denture bases and have adverse effects on the oral mucosa. This in vitro study evaluated and correlated the effect of the leaching residual MMA concentrations ([MMA]r) on in vitro cytotoxicity of L-929 fibroblasts. A total of 144 heat-polymerized acrylic resin specimens were fabricated using 4 different polymerization cycles: (1) at 74ºC for 9 h, (2) at 74ºC for 9 h and terminal boiling (at 100ºC) for 30 min, (3) at 74ºC for 9 h and terminal boiling for 3 h, (4) at 74ºC for 30 min and terminal boiling for 30 min. Specimens were eluted in a complete cell culture medium at 37ºC for 1, 2, 5 and 7 days. [MMA]r in eluates was measured using high-performance liquid chromatography. In vitro cytotoxicity of eluates on L-929 fibroblasts was evaluated by means of cell proliferation using a tetrazolium salt XTT (sodium 3´-[1-phenyl-aminocarbonyl)-3,4-tetrazolium]bis(4-methoxy-6-nitro)benzenesulphonic acid) assay. Differences in [MMA]r of eluates and cell proliferation values between polymerization cycles were statistically analyzed by Kruskal-Wallis, Friedman and Dunn's multiple comparison tests. The correlation between [MMA]r of eluates and cell proliferation was analyzed by Pearson's correlation test (p<0.05). [MMA]r was significantly (p<0.001) higher in eluates of specimens polymerized with cycle without terminal boiling after elution of 1 and 2 days. Cell proliferation values for all cycles were significantly (p<0.01) lower in eluates of 1 day than those of 2 days. The correlation between [MMA]r and cell proliferation values was negative after all elution periods, showing significance (p<0.05) for elution of 1 and 2 days. MMA continued to leach from acrylic resin throughout 7 days and leaching concentrations markedly reduced after elution of 1 and 2 days. Due to reduction of leaching residual MMA concentrations, use of terminal boiling in the polymerization process for at least 30 min and water

  18. Effect of leaching residual methyl methacrylate concentrations on in vitro cytotoxicity of heat polymerized denture base acrylic resin processed with different polymerization cycles

    Directory of Open Access Journals (Sweden)

    Canan Bural

    2011-08-01

    the polymerization process for at least 30 min and water storage of the heat-polymerized denture bases for at least 1 to 2 days before denture delivery is clinically recommended for minimizing the residual MMA and possible cytotoxic effects.

  19. Management of NORM Residues

    International Nuclear Information System (INIS)

    2013-06-01

    The IAEA attaches great importance to the dissemination of information that can assist Member States in the development, implementation, maintenance and continuous improvement of systems, programmes and activities that support the nuclear fuel cycle and nuclear applications, and that address the legacy of past practices and accidents. However, radioactive residues are found not only in nuclear fuel cycle activities, but also in a range of other industrial activities, including: - Mining and milling of metalliferous and non-metallic ores; - Production of non-nuclear fuels, including coal, oil and gas; - Extraction and purification of water (e.g. in the generation of geothermal energy, as drinking and industrial process water; in paper and pulp manufacturing processes); - Production of industrial minerals, including phosphate, clay and building materials; - Use of radionuclides, such as thorium, for properties other than their radioactivity. Naturally occurring radioactive material (NORM) may lead to exposures at some stage of these processes and in the use or reuse of products, residues or wastes. Several IAEA publications address NORM issues with a special focus on some of the more relevant industrial operations. This publication attempts to provide guidance on managing residues arising from different NORM type industries, and on pertinent residue management strategies and technologies, to help Member States gain perspectives on the management of NORM residues

  20. An improved crude oil atmospheric distillation process for energy integration: Part II: New approach for energy saving by use of residual heat

    International Nuclear Information System (INIS)

    Benali, Tahar; Tondeur, Daniel; Jaubert, Jean Noël

    2012-01-01

    In Part I of this paper, it was shown on thermodynamic grounds that introducing a flash in the preheating train of an atmospheric oil distillation process, together with an appropriate introduction of the resulting vapour into the column, could potentially bring substantial energy savings, by reducing the duty of the preheating furnace, by doing some pre-fractionation and by reducing the column irreversibilities. Part II expands on this idea by showing how this can be done while keeping the throughput and the product characteristics unchanged. The outcome is that placing several flashes after the heat exchangers and feeding the corresponding vapour streams to the appropriate trays of the column reduces the pumparound flows and the heat brought to the preheating train. The resulting heat deficit may then be compensated in an additional heat exchanger by using low level heat recuperated from the products of the distillation and/or imported from other processes. The use of this residual heat reduces the furnace duty by approximately an equivalent amount. Thus high level energy (fuel-gas burnt in the furnace) is replaced by residual low level heat. The simulation with an example flowsheet shows that the savings on fuel could be as high as 21%. - Highlights: ► Flash installation in the preheating train of the crude oil distillation process. ► Pumparound streams and heat sent to the preheating train are reduced. ► A high level heat deficit is induced and replaced by low level heat. ► Considerable energy savings and greenhouse gas emissions are achieved.

  1. Conservation characteristics of corn ears and stover ensiled with the addition of Lactobacillus plantarum MTD-1, Lactobacillus plantarum 30114, or Lactobacillus buchneri 11A44.

    Science.gov (United States)

    Lynch, J P; O'Kiely, P; Waters, S M; Doyle, E M

    2012-04-01

    The aim of this study was to investigate the effects of inoculating 3 contrasting lactic acid bacteria on the fermentation profile, estimated nutritive value, and aerobic stability of corn ears and stover produced under marginal growing conditions. Ears and stover were separated from whole-crop corn plants obtained from 3 replicate field blocks. Representative subsamples were precision chopped and allocated to 1 of the following treatments: an uninoculated control, Lactobacillus plantarum MTD-1 (LP1), L. plantarum 30114 (LP2), or Lactobacillus buchneri 11A44 (LB). Each bacterial additive was applied at a rate of 1 × 10(6) cfu/g of fresh herbage. Triplicate samples of each treatment were ensiled in laboratory silos at 15°C for 3, 10, 35, or 130 d. No difference was observed between the dry matter recoveries of uninoculated ear or stover silages and silages made with LP1, and the aerobic stability of uninoculated ear and stover silages did not differ from silages made with LB. Stover silages made with LP2 and ensiled for 35 d had a lower proportion of lactic acid in total fermentation products compared with LP1. The aerobic stability and dry matter recovery of ear and stover silages in this study were not improved when made with LB, LP1, or LP2, due to the indigenous highly heterolactic fermentation that prevailed in the uninoculated ear and stover during 130-d ensilage. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  2. Enhancing cellulose accessibility of corn stover by deep eutectic solvent pretreatment for butanol fermentation.

    Science.gov (United States)

    Xu, Guo-Chao; Ding, Ji-Cai; Han, Rui-Zhi; Dong, Jin-Jun; Ni, Ye

    2016-03-01

    In this study, an effective corn stover (CS) pretreatment method was developed for biobutanol fermentation. Deep eutectic solvents (DESs), consisted of quaternary ammonium salts and hydrogen donors, display similar properties to room temperature ionic liquid. Seven DESs with different hydrogen donors were facilely synthesized. Choline chloride:formic acid (ChCl:formic acid), an acidic DES, displayed excellent performance in the pretreatment of corn stover by removal of hemicellulose and lignin as confirmed by SEM, FTIR and XRD analysis. After optimization, glucose released from pretreated CS reached 17.0 g L(-1) and yield of 99%. The CS hydrolysate was successfully utilized in butanol fermentation by Clostridium saccharobutylicum DSM 13864, achieving butanol titer of 5.63 g L(-1) with a yield of 0.17 g g(-1) total sugar and productivity of 0.12 g L(-1)h(-1). This study demonstrates DES could be used as a promising and biocompatible pretreatment method for the conversion of lignocellulosic biomass into biofuel. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Synergistic Enhancement of Cellobiohydrolase Performance on Pretreated Corn Stover by Addition of Xylanase and Esterase Activities

    Energy Technology Data Exchange (ETDEWEB)

    Selig, M. J.; Knoshaug E. P.; Adney, W. S.; Himmel, M. E.; Decker, S. R.

    2007-11-01

    Significant increases in the depolymerization of corn stover cellulose by cellobiohydrolase I (Cel7A) from Trichoderma reesei were observed using small quantities of non-cellulolytic cell wall-degrading enzymes. Purified endoxylanase (XynA), ferulic acid esterase (FaeA), and acetyl xylan esterase (Axe1) all enhanced Cel7A performance on corn stover subjected to hot water pretreatment. In all cases, the addition of these activities improved the effectiveness of the enzymatic hydrolysis in terms of the quantity of cellulose converted per milligram of total protein. Improvement in cellobiose release by the addition of the non-cellulolytic enzymes ranged from a 13-84% increase over Cel7A alone. The most effective combinations included the addition of both XynA and Axe1, which synergistically enhance xylan conversions resulting in additional synergistic improvements in glucan conversion. Additionally, we note a direct relationship between enzymatic xylan removal in the presence of XynA and the enhancement of cellulose hydrolysis by Cel7A.

  4. Recycling the liquid fraction of alkaline hydrogen peroxide in the pretreatment of corn stover.

    Science.gov (United States)

    Alencar, Bárbara Ribeiro Alves; Reis, Alexandre Libanio Silva; de Souza, Raquel de Fatima Rodrigues; Morais, Marcos Antônio; Menezes, Rômulo Simões Cezar; Dutra, Emmanuel Damilano

    2017-10-01

    The aim of this study was to evaluate the influence of recycling the liquid fraction of pretreatment with alkaline hydrogen peroxide (AHP) on the hydrolysis of corn stover. Corn stover was pretreated in the traditional condition with 7.5% v/v H 2 O 2 . After pretreatment, the solids were separated from the liquid fraction and five successive reuse cycles of the liquid fraction were tested. The solid fraction from pretreatment in each recycle was submitted to enzymatic hydrolysis. The number of recycles had a linear negative effect (R 2 =0.98) on biomass delignification efficiency and also affected negatively the enzymatic conversion efficiency. Despite the decrease in efficiency after each recycling step, reuse of the liquid fraction leads to reduction in water, H 2 O 2 and NaOH consumption of up to 57.6%, 59.6% and 57.6%, respectively. These findings point to an efficient recycling technology, which may reduce costs and save water. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Mutagenic Effect of Ethanol Extract of Jatropha Curcas L Seed Solid Waste Obtained From Residual Fuel Vegetable Processing (Biofuel)

    OpenAIRE

    Wahyuningrum, Retno; Wirasutisna, Komar Ruslan; Elfahmi, Elfahmi; Wibowo, Marlia Singgih

    2010-01-01

    Jatropha curcas seed contains viscous oil that can be used for soap making, cosmetic and as biofuel. It contains phorbol ester that was toxic. Biofuel production of Jatropha curcas seed left seedcake from mechanical press process. For safety evaluation, mutagenicity test was carried out. The seedcake was extracted by maceration method at room temperature with methanol and the mutagenic effect was evaluated by Ames test against Salmonella typhimurium TA 1535 with or without S9 metabolic activa...

  6. Greek "red mud" residue: a study of microwave reductive roasting followed by magnetic separation for a metallic iron recovery process.

    Science.gov (United States)

    Samouhos, Michail; Taxiarchou, Maria; Tsakiridis, Petros E; Potiriadis, Konstantinos

    2013-06-15

    The present research work is focused on the development of an alternative microwave reductive roasting process of red mud using lignite (30.15 wt.%Cfix), followed by wet magnetic separation, in order to produce a raw material suitable for sponge or cast iron production. The reduction degree of iron was controlled by both the reductive agent content and the microwave heating time. The reduction followed the Fe₂O₃ → Fe₃O₄ → FeO → Fe sequence. The dielectric constants [real (ε') and imaginary (ε″) permittivities] of red mud-lignite mixture were determined at 2.45 GHz, in the temperature range of 25-1100 °C. The effect of parameters such as temperature, intensity of reducing conditions, intensity of magnetic field and dispersing agent addition rate on the result of both processes was investigated. The phase's transformations in reduction process with microwave heating were determined by X-ray diffraction analysis (XRD) in combination with thermogravimetric/differential thermal analysis (TGA/DTA). The microstructural and morphological characterization of the produced calcines was carried out by scanning electron microscopy (SEM). At the optimum conditions a magnetic concentrate with total iron concentration of 35.15 and 69.3 wt.% metallization degree was obtained. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Adaptation of continuous biogas reactors operating under wet fermentation conditions to dry conditions with corn stover as substrate.

    Science.gov (United States)

    Kakuk, Balázs; Kovács, Kornél L; Szuhaj, Márk; Rákhely, Gábor; Bagi, Zoltán

    2017-08-01

    Corn stover (CS) is the agricultural by-product of maize cultivation. Due to its high abundance and high energy content it is a promising substrate for the bioenergy sector. However, it is currently neglected in industrial scale biogas plants, because of its slow decomposition and hydrophobic character. To assess the maximum biomethane potential of CS, long-term batch fermentations were carried out with various substrate concentrations and particle sizes for 72 days. In separate experiments we adapted the biogas producing microbial community in wet fermentation arrangement first to the lignocellulosic substrate, in Continuous Stirred Tank Reactor (CSTR), then subsequently, by continuously elevating the feed-in concentration, to dry conditions in solid state fermenters (SS-AD). In the batch tests, the produce 90% of the total biomethane yield than the amount of substrate added to the fermentation lowered the specific methane yield. In the CSTR experiment, the daily substrate loading was gradually increased from 1 to 2 g vs /L/day until the system produced signs of overloading. Then the biomass was transferred to SS-AD reactors and the adaptation process was studied. Although the specific methane yields were lower in the SS-AD arrangement (177 mL CH 4 /g vs in CSTR vs. 105 mL in SS-AD), the benefits of process operational parameters, i.e. lower energy consumption, smaller reactor volume, digestate amount generated and simpler configuration, may compensate the somewhat lower yield. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. s-process studies in the light of new experimental cross sections: Distribution of neutron fluences and r-process residuals

    International Nuclear Information System (INIS)

    Kaeppeler, F.; Beer, H.; Wisshak, K.; Clayton, D.D.; Macklin, R.L.; Ward, R.A.

    1981-08-01

    A best set of neutron-capture cross sections has been evaluated for the most important s-process isotopes. With this data base, s-process studies have been carried out using the traditional model which assumes a steady neutron flux and an exponential distribution of neutron irradiations. The calculated sigmaN-curve is in excellent agreement with the empirical sigmaN-values of pure s-process nuclei. Simultaneously, good agreement is found between the difference of solar and s-process abundances and the abundances of pure r-process nuclei. We also discuss the abundance pattern of the iron group elements where our s-process results complement the abundances obtained from explosive nuclear burning. The results obtained from the traditional s-process model such as seed abundances, mean neutron irradiations, or neutron densities are compared to recent stellar model calculations which assume the He-burning shells of red giant stars as the site for the s-process. (orig.) [de

  9. Response surface methodology (RSM) to evaluate moisture effects on corn stover in recovering xylose by DEO hydrolysis

    Science.gov (United States)

    Rita C.L.B. Rodrigues; William R. Kenealy; Diane Dietrich; Thomas W. Jeffries

    2012-01-01

    Response surface methodology (RSM), based on a 22 full factorial design, evaluated the moisture effects in recovering xylose by diethyloxalate (DEO) hydrolysis. Experiments were carried out in laboratory reactors (10 mL glass ampoules) containing corn stover (0.5 g) properly ground. The ampoules were kept at 160 °C for 90 min. Both DEO...

  10. Biological pretreatment of corn stover with Phlebia brevispora NRRL-13108 for enhanced enzymatic hydrolysis and efficient ethanol production

    Science.gov (United States)

    Biological pretreatment of lignocellulosic biomass by white-rot fungus can represent a low-cost and eco-friendly alternative to harsh physical, chemical, or physico-chemical pretreatment methods to facilitate enzymatic hydrolysis. In this work, solid state cultivation of corn stover with Phlebia bre...

  11. Chemical properties and antioxidant activity of exopolysaccharides fractions from mycelial culture of Inonotus obliquus in a ground corn stover medium.

    Science.gov (United States)

    Xiang, Yuling; Xu, Xiangqun; Li, Juan

    2012-10-15

    The medicinal mushroom Inonotus obliquus has been a folk remedy for a long time in East-European and Asian countries. We first reported the enhancement in production and antioxidant activity of exopolysaccharides by I. obliquus culture under lignocellulose decomposition. In this study, the two different sources of exopolysaccharides from the control medium and the lignocellulose (corn stover) containing medium by I. obliquus in submerged fermentation were fractionated and purified by chromatography. The exopolysaccharides from the corn stover-containing medium presented significantly stronger hydroxyl and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity than the control. Three fractions from the control medium and the corn stover-containing medium were isolated respectively. The fraction of DEPL3 from the corn stover-containing medium with the highest protein content (38.3%), mannose content (49.6%), and the lowest molecular weight (29 kDa) had the highest antioxidant activity with the lowest IC50 values. In conclusion, lignocellulose decomposition changed the chemical characterisation and significantly enhanced the antioxidant activity of exopolysaccharide fractions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Production, carbon and nitrogen in stover fractions of corn ( Zea mays L. in response to cultivar development

    Directory of Open Access Journals (Sweden)

    Julierme Zimmer Barbosa

    Full Text Available ABSTRACT Changes in quantity and quality of corn crop stover can have a large impact on soil conservation and soil carbon (C sequestration over large areas. The aim of this study was to evaluate changes in production, concentration and amount of C and nitrogen (N in corn stover fractions due to cultivar development. Two field experiments were conducted in the city of Rolândia (Paraná State, Brazil using ten cultivars representing five technological levels: single cross hybrids, double or triple hybrids, commercial varieties, and creole cultivars. Plant heights and stalk, leaf, cob, husk and tassel weights were determined at final harvest. Elemental C and N analyses were performed in triplicate for each stover fraction. In general, the creole cultivars had greater height, more dry matter (kg ha-1 and C content (kg ha-1 in husks, leaves, tassels and stalks, particularly when compared to single cross hybrids or others hybrids. There was a direct relationship between C/N ratio and corn selection for husks in both years and for the others fractions in one study year. This was due to the combined effects of increasing C and decreasing N due to crop selection. Large differences were observed within the same technological levels for the evaluated properties, suggesting a wide variation in genetic background. The quantity and quality of stover fractions vary among cultivars and may affect their use for soil cover, animal feed, biomass energy and other applications.

  13. Evaluating corn starch and corn stover biochar as renewable filler in carboxylated styrene-butadiene rubber composites

    Science.gov (United States)

    Corn starch, corn flour, and corn stover biochar were evaluated as potential renewable substitutes for carbon black as filler in rubber composites using carboxylated styrene-butadiene as the rubber matrix. Previous work has shown that starch-based fillers have very good reinforcement properties at t...

  14. Residual basins

    International Nuclear Information System (INIS)

    D'Elboux, C.V.; Paiva, I.B.

    1980-01-01

    Exploration for uranium carried out over a major portion of the Rio Grande do Sul Shield has revealed a number of small residual basins developed along glacially eroded channels of pre-Permian age. Mineralization of uranium occurs in two distinct sedimentary units. The lower unit consists of rhythmites overlain by a sequence of black shales, siltstones and coal seams, while the upper one is dominated by sandstones of probable fluvial origin. (Author) [pt

  15. Marine Tar Residues: a Review

    OpenAIRE

    Warnock, April M.; Hagen, Scott C.; Passeri, Davina L.

    2015-01-01

    Marine tar residues originate from natural and anthropogenic oil releases into the ocean environment and are formed after liquid petroleum is transformed by weathering, sedimentation, and other processes. Tar balls, tar mats, and tar patties are common examples of marine tar residues and can range in size from millimeters in diameter (tar balls) to several meters in length and width (tar mats). These residues can remain in the ocean environment indefinitely, decomposing or becoming buried in ...

  16. Variations in fuel characteristics of corn (Zea mays) stovers: General spatial patterns and relationships to soil properties

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Shaojun [Unit of Biomass Technology and Chemistry, Swedish University of Agricultural Sciences, SE-901 83 Umeaa (Sweden); College of Life Science, Beijing Normal University, Beijing (China); Zhang, Yufen [College of Life Science, Beijing Normal University, Beijing (China); Zhuo, Yue [Biomass Engineering Centre, China Agricultural University, Beijing (China); Lestander, Torbjoern; Geladi, Paul [Unit of Biomass Technology and Chemistry, Swedish University of Agricultural Sciences, SE-901 83 Umeaa (Sweden)

    2010-06-15

    The geographic variations in corn stover fuel and soil characteristics from 22 sites in the Kerchin region (43.8-45.0 N, 122.7-125.1 E), north-east China, were examined in both 2006 and 2007. The correlations between fuel characteristics and soil parameters were analysed using principal component analysis (PCA) and partial least squares regression (PLS). The main emphasis was on the feasibility of using corn stovers as feedstock in direct combustion for heat and power generation. The examined corn stovers from Kerchin generally have similar characteristics to energy grasses grown in Europe and may be used as biofuels. However, large variations, up to several orders of magnitude, in the fuel characteristics existed among the samples. With PCA, the studied soils showed a clear distinction between soluble and less soluble elements, with a trend for higher insoluble element (such as Si) concentrations in south-western soils and a higher pH in the more northern soils. The component for fuel characteristics showed a distinct trend with latitude that can be explained by the above-mentioned soil component pattern. PLS regression models suggested some important relationships that may be used to predict corn stover fuel characteristics using soil and environment properties; for example, latitude, soil pH and Si are the most important predictors for Ca content in corn stovers, but not for K that is best predicted by soil K. Although limited by numbers of samples and sites, this study indicated that this approach can be used to predict biofuel quality. (author)

  17. Removal of pharmaceutical residues using ozonation as intermediate process step at Linköping WWTP, Sweden.

    Science.gov (United States)

    Baresel, Christian; Malmborg, Jonas; Ek, Mats; Sehlén, Robert

    2016-01-01

    Pilot tests as basis for the design, implementation and operation of a future full-scale oxidation