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Sample records for alkaline-pretreated corn stover

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

    Directory of Open Access Journals (Sweden)

    Chen Ye

    2013-01-01

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

  2. Simultaneous saccharification and fermentation of alkaline-pretreated corn stover to ethanol using a recombinant yeast strain

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    Zhao, Jing; Xia, Liming [Department of Chemical and Biochemical Engineering, Zhejiang University, Hangzhou 310027 (China)

    2009-10-15

    Bio-ethanol converted from cheap and abundant lignocellulosic materials is a potential renewable resource to replace depleting fossil fuels. Simultaneous saccharification and fermentation (SSF) of alkaline-pretreated corn stover for the production of ethanol was investigated using a recombinant yeast strain Saccharomyces cerevisiae ZU-10. Low cellobiase activity in Trichoderma reesei cellulase resulted in cellobiose accumulation. Supplementing the simultaneous saccharification and fermentation system with cellobiase greatly reduced feedback inhibition caused by cellobiose to the cellulase reaction, thereby increased the ethanol yield. 12 h of enzymatic prehydrolysis at 50 C prior to simultaneous saccharification and fermentation was found to have a negative effect on the overall ethanol yield. Glucose and xylose produced from alkaline-pretreated corn stover could be co-fermented to ethanol effectively by S. cerevisiae ZU-10. An ethanol concentration of 27.8 g/L and the corresponding ethanol yield on carbohydrate in substrate of 0.350 g/g were achieved within 72 h at 33 C with 80 g/L of substrate and enzyme loadings of 20 filter paper activity units (FPU)/g substrate and 10 cellobiase units (CBU)/g substrate. The results are meaningful in co-conversion of cellulose and hemicellulose fraction of lignocellulosic materials to fuel ethanol. (author)

  3. Fast and efficient nanoshear hybrid alkaline pretreatment of corn stover for biofuel and materials production

    International Nuclear Information System (INIS)

    Wang, Wei; Ji, Shaowen; Lee, Ilsoon

    2013-01-01

    We report a fast and efficient nano-scale shear hybrid alkaline (NSHA) pretreatment method of lignocellulosic biomass. In this work, corn stover was pretreated in a modified Taylor–Couette reactor with alkali (sodium hydroxide) at room temperature for two minutes. Up to 82% of high cellulose content in the remaining solids was achieved with the novel NSHA pretreatment process. Compared with untreated corn stover, an approximately 4-fold increase in enzymatic cellulose conversion and a 5-fold increase in hemicellulose conversion were achieved. Compositional analysis proved significant removals of both lignin and hemicellulose after the NSHA pretreatment. SEM images revealed that the synergistic effect of NSHA pretreatment caused the severe disruption of biomass structure and exposure of cellulose microfibril aggregates in NSHA pretreated corn stover. Highlights: ► A fast nanoshear hybrid alkaline (NSHA) pretreatment method is reported. ► A modified Taylor–Couette reactor was applied. ► The retention time of the NSHA method is only 2 min. ► A 100% conversion of glucan was achieved in one day. ► NSHA greatly removed both lignin and xylan

  4. BIOFUEL FROM CORN STOVER

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    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. %.

  5. Spring harvest of corn stover

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    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.

  6. Bioconversion of corn stover hydrolysate to ethanol by a recombinant yeast strain

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    Zhao, Jing; Xia, Liming

    2010-12-15

    Three corn stover hydrolysates, enzymatic hydrolysates prepared from acid and alkaline pretreatments separately and hemicellulosic hydrolysate prepared from acid pretreatment, were evaluated in composition and fermentability. For enzymatic hydrolysate from alkaline pretreatment, ethanol yield on fermentable sugars and fermentation efficiency reached highest among the three hydrolysates; meanwhile, ethanol yield on dry corn stover reached 0.175 g/g, higher than the sum of those of two hydrolysates from acid pretreatment. Fermentation process of the enzymatic hydrolysate from alkaline pretreatment was further investigated using free and immobilized cells of recombinant Saccharomyces cerevisiae ZU-10. Concentrated hydrolysate containing 66.9 g/L glucose and 32.1 g/L xylose was utilized. In the fermentation with free cells, 41.2 g/L ethanol was obtained within 72 h with an ethanol yield on fermentable sugars of 0.416 g/g. Immobilized cells greatly enhanced the ethanol productivity, while the ethanol yield on fermentable sugars of 0.411 g/g could still be reached. Repeated batch fermentation with immobilized cells was further attempted up to six batches. The ethanol yield on fermentable sugars maintained above 0.403 g/g with all glucose and more than 92.83% xylose utilized in each batch. These results demonstrate the feasibility and efficiency of ethanol production from corn stover hydrolysates. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. Production of ethanol and furfural from corn stover

    Science.gov (United States)

    Corn stover has potential for economical production of biofuels and value-added chemicals. The conversion of corn stover to sugars involves pretreatment and enzymatic hydrolysis. We have optimized hydrothermal, dilute H2SO4 and dilute H3PO4 pretreatments of corn stover for enzymatic saccharificati...

  9. 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...

  10. 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.

  11. 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 <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. PMID:29632861

  12. Corn Stover Availability for Biomass Conversion: Situation Analysis

    International Nuclear Information System (INIS)

    Hess, J. Richard; Kenney, Kevin L.; Wright, Christopher T.; Perlack, Robert; Turhollow, Anthony

    2009-01-01

    As biorefining conversion technologies become commercial, feedstock availability, supply system logistics, and biomass material attributes are emerging as major barriers to the availability of corn stover for biorefining. While systems do exist to supply corn stover as feedstock to biorefining facilities, stover material attributes affecting physical deconstruction, such as densification and post-harvest material stability, challenge the cost-effectiveness of present-day feedstock logistics systems. In addition, the material characteristics of corn stover create barriers with any supply system design in terms of equipment capacity/efficiency, dry matter loss, and capital use efficiency. However, this study of a large, square-bale corn stover feedstock supply system concludes that (1) where other agronomic factors are not limiting, corn stover can be accessed and supplied to a biorefinery using existing bale-based technologies, (2) technologies and new supply system designs are necessary to overcome biomass bulk density and moisture material property challenges, and (3) major opportunities to improve conventional-bale biomass feedstock supply systems include improvements in equipment efficiency and capacity and reducing biomass losses in harvesting and collection and storage. Finally, the backbone of an effective stover supply system design is the optimization of intended and minimization of unintended material property changes as the corn stover passes through the individual supply system processes from the field to the biorefinery conversion processes

  13. Effect of dilute alkaline pretreatment on the conversion of different parts of corn stalk to fermentable sugars and its application in acetone-butanol-ethanol fermentation.

    Science.gov (United States)

    Cai, Di; Li, Ping; Luo, Zhangfeng; Qin, Peiyong; Chen, Changjing; Wang, Yong; Wang, Zheng; Tan, Tianwei

    2016-07-01

    To investigate the effect of dilute alkaline pretreatment on different parts of biomass, corn stalk was separated into flower, leaf, cob, husk and stem, which were treated by NaOH in range of temperature and chemical loading. The NaOH-pretreated solid was then enzymatic hydrolysis and used as the substrate for batch acetone-butanol-ethanol (ABE) fermentation. The results demonstrated the five parts of corn stalk could be used as potential feedstock separately, with vivid performances in solvents production. Under the optimized conditions towards high product titer, 7.5g/L, 7.6g/L, 9.4g/L, 7g/L and 7.6g/L of butanol was obtained in the fermentation broth of flower, leaf, cob, husk and stem hydrolysate, respectively. Under the optimized conditions towards high product yield, 143.7g/kg, 126.3g/kg, 169.1g/kg, 107.7g/kg and 116.4g/kg of ABE solvent were generated, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Reductive Catalytic Fractionation of Corn Stover Lignin

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    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

  15. Maleic acid treatment of biologically detoxified corn stover liquor.

    Science.gov (United States)

    Kim, Daehwan; Ximenes, Eduardo A; Nichols, Nancy N; Cao, Guangli; Frazer, Sarah E; Ladisch, Michael R

    2016-09-01

    Elimination of microbial and enzyme inhibitors from pretreated lignocellulose is critical for effective cellulose conversion and yeast fermentation of liquid hot water (LHW) pretreated corn stover. In this study, xylan oligomers were hydrolyzed using either maleic acid or hemicellulases, and other soluble inhibitors were eliminated by biological detoxification. Corn stover at 20% (w/v) solids was LHW pretreated LHW (severity factor: 4.3). The 20% solids (w/v) pretreated corn stover derived liquor was recovered and biologically detoxified using the fungus Coniochaeta ligniaria NRRL30616. After maleic acid treatment, and using 5 filter paper units of cellulase/g glucan (8.3mg protein/g glucan), 73% higher cellulose conversion from corn stover was obtained for biodetoxified samples compared to undetoxified samples. This corresponded to 87% cellulose to glucose conversion. Ethanol production by yeast of pretreated corn stover solids hydrolysate was 1.4 times higher than undetoxified samples, with a reduction of 3h in the fermentation lag phase. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Thermophysical properties of conjugated soybean oil/corn stover biocomposites.

    Science.gov (United States)

    Pfister, Daniel P; Larock, Richard C

    2010-08-01

    Novel "green composites" have been prepared using a conjugated soybean oil-based resin and corn stover as a natural fiber. Corn stover is the residue remaining after grain harvest and it is estimated that approximately 75 million tons are available annually in the United States. The effect of the amount of filler, the length of the fiber, and the amount of the crosslinker on the structure and thermal and mechanical properties of the composites has been determined using Soxhlet extraction analysis, thermogravimetric analysis, dynamic mechanical analysis, and tensile testing. Increasing the amount of corn stover and decreasing the length of the fiber results in significant improvements in the mechanical properties of the composites. The Young's moduli and tensile strengths of the composites prepared range from 291 to 1398 MPa and 2.7 to 7.4 MPa, respectively. Water uptake data indicate that increasing the amount and fiber length of the corn stover results in significant increases in the absorption of water by the composites. The composites, containing 20 to 80 wt.% corn stover and a resin composed of 50 wt.% natural oil, contain 60 to 90 wt.% renewable materials and should find applications in the construction, automotive, and furniture industries. (c) 2010 Elsevier Ltd. All rights reserved.

  17. Alkaline Peroxide Delignification of Corn Stover

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    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.

  18. Pretreatment on Corn Stover with Low Concentration of Formic Acid

    DEFF Research Database (Denmark)

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

    2009-01-01

    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...... 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...

  19. 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.

  20. 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.

  1. 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...

  2. Structural changes of corn stover lignin during acid pretreatment.

    Science.gov (United States)

    Moxley, Geoffrey; Gaspar, Armindo Ribeiro; Higgins, Don; Xu, Hui

    2012-09-01

    In this study, raw corn stover was subjected to dilute acid pretreatments over a range of severities under conditions similar to those identified by the National Renewable Energy Laboratory (NREL) in their techno-economic analysis of biochemical conversion of corn stover to ethanol. The pretreated corn stover then underwent enzymatic hydrolysis with yields above 70 % at moderate enzyme loading conditions. The enzyme exhausted lignin residues were characterized by ³¹P NMR spectroscopy and functional moieties quantified and correlated to enzymatic hydrolysis yields. Results from this study indicated that both xylan solubilization and lignin degradation are important for improving the enzyme accessibility and digestibility of dilute acid pretreated corn stover. At lower pretreatment temperatures, there is a good correlation between xylan solubilization and cellulose accessibility. At higher pretreatment temperatures, lignin degradation correlated better with cellulose accessibility, represented by the increase in phenolic groups. During acid pretreatment, the ratio of syringyl/guaiacyl functional groups also gradually changed from less than 1 to greater than 1 with the increase in pretreatment temperature. This implies that more syringyl units are released from lignin depolymerization of aryl ether linkages than guaiacyl units. The condensed phenolic units are also correlated with the increase in pretreatment temperature up to 180 °C, beyond which point condensation reactions may overtake the hydrolysis of aryl ether linkages as the dominant reactions of lignin, thus leading to decreased cellulose accessibility.

  3. Sustainability of corn stover harvest strategies in Pennsylvania

    Science.gov (United States)

    Pennsylvania has a long history of harvesting corn 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...

  4. 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 ...

  5. Mild alkaline presoaking and organosolv pretreatment of corn stover and their impacts on corn stover composition, structure, and digestibility.

    Science.gov (United States)

    Qing, Qing; Zhou, Linlin; Guo, Qi; Gao, Xiaohang; Zhang, Yan; He, Yucai; Zhang, Yue

    2017-06-01

    An efficient strategy was developed in current work for biochemical conversion of carbohydrates of corn stover into monosaccharides. Corn stover was first presoaked in mild alkaline solution (1% Na 2 S) under 40°C for 4h, after which about 35.3% of the lignin was successfully removed while the specific surface area was notably enlarged. Then the presoaked solids were subjected to organosolv pretreatment that employed 20% methanol with an addition of 0.2% HCl as catalyst at 160°C for 20min, and the maximum total sugar yield of the pretreated corn stover achieved was 98.6%. The intact structure of corn stover was disrupted by this two-step process, which resulted in a porous but crystalline structure of the regenerated solids that were mainly composed of cellulose. The enlarged specific surface area and increased accessibility made the regenerated solids highly digestible by a moderate enzyme loading. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. 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.

  7. Mathematical tool from corn stover TGA to determine its composition.

    Science.gov (United States)

    Freda, Cesare; Zimbardi, Francesco; Nanna, Francesco; Viola, Egidio

    2012-08-01

    Corn stover was treated by steam explosion process at four different temperatures. A fraction of the four exploded matters was extracted by water. The eight samples (four from steam explosion and four from water extraction of exploded matters) were analysed by wet chemical way to quantify the amount of cellulose, hemicellulose and lignin. Thermogravimetric analysis in air atmosphere was executed on the eight samples. A mathematical tool was developed, using TGA data, to determine the composition of corn stover in terms of cellulose, hemicellulose and lignin. It uses the biomass degradation temperature as multiple linear function of the cellulose, hemicellulose and lignin content of the biomass with interactive terms. The mathematical tool predicted cellulose, hemicellulose and lignin contents with average absolute errors of 1.69, 5.59 and 0.74 %, respectively, compared to the wet chemical method.

  8. Enhancing the enzymatic hydrolysis of corn stover by an integrated wet-milling and alkali pretreatment.

    Science.gov (United States)

    He, Xun; Miao, Yelian; Jiang, Xuejian; Xu, Zidong; Ouyang, Pingkai

    2010-04-01

    An integrated wet-milling and alkali pretreatment was applied to corn stover prior to enzymatic hydrolysis. The effects of NaOH concentration in the pretreatment on crystalline structure, chemical composition, and reducing-sugar yield of corn stover were investigated, and the mechanism of increasing reducing-sugar yield by the pretreatment was discussed. The experimental results showed that the crystalline structure of corn stover was disrupted, and lignin was removed, while cellulose and hemicellulose were retained in corn stover by the pretreatment with 1% NaOH in 1 h. The reducing-sugar yield from the pretreated corn stovers increased from 20.2% to 46.7% when the NaOH concentration increased from 0% to 1%. The 1% NaOH pretreated corn stover had a holocellulose conversion of 55.1%. The increase in reducing-sugar yield was related to the crystalline structure disruption and delignification of corn stover. It was clarified that the pretreatment significantly enhanced the conversion of cellulose and hemicellulose in the corn stover to sugars.

  9. 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.

  10. Assessment of the Nutritive Value of Whole Corn Stover and Its Morphological Fractions

    Directory of Open Access Journals (Sweden)

    H. Y. Li

    2014-02-01

    Full Text Available This study investigated the chemical composition and ruminal degradability of corn stover in three maize-planting regions in Qiqihaer, Heilongjiang Province, China. The whole stover was separated into seven morphological fractions, i.e., leaf blade, leaf sheath, stem rind, stem pith, stem node, ear husk, and corn tassel. The assessment of nutritive value of corn stover and its fractions was performed based on laboratory assays of the morphological proportions, chemical composition, and in situ degradability of dry matter (DM, neutral detergent fiber (NDF, and acid detergent fiber (ADF. The chemical composition of corn stover was significantly different from plant top to bottom (p<0.05. Among the whole corn stover and seven morphological fractions, leaf blade had the highest crude protein (CP content and the lowest NDF and ADF contents (p<0.05, whereas stem rind had the lowest CP content and the highest ADF and acid detergent lignin (ADL contents (p<0.05. Ear husk had significantly higher NDF content and relatively lower ADL content than other corn stover fractions. Overall, the effective degradability of DM, NDF, and ADF in rumen was the highest in leaf blade and stem pith, followed by ear husk. The results indicate that leaf blade, ear husk, and stem pith potentially have higher nutritive values than the other fractions of corn stover. This study provides reference data for high-efficiency use of corn stover in feeding ruminants.

  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. A GIS methodology to identify potential corn stover collection locations

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, Monica A. [Department of Community and Regional Planning, 583 College of Design, Iowa State University, Ames, IA 50011-3095 (United States); Anderson, Paul F. [Department of Landscape Architecture, 481 College of Design, Iowa State University, Ames, IA 50011 (United States); Department of Agronomy, 481 College of Design, Iowa State University, Ames, IA 50011 (United States)

    2008-12-15

    In this study, we use geographic information systems technology to identify potential locations in a Midwestern region for collection and storage of corn stover for use as biomass feedstock. Spatial location models are developed to identify potential collection sites along an existing railroad. Site suitability analysis is developed based on two main models: agronomic productivity potential and environmental costs. The analysis includes the following steps: (1) elaboration of site selection criteria; (2) identification of the study region and service area based on transportation network analysis; (3) reclassification of input spatial layers based on common scales; (4) overlaying the reclassified spatial layers with equal weights to generate the two main models; and (5) overlaying the main models using different weights. A pluralistic approach is adopted, presenting three different scenarios as alternatives for the potential locations. Our results suggest that there is a significant subset of potential sites that meet site selection criteria. Additional studies are needed to evaluate potential sites through field visits, assess economic and social costs, and estimate the proportion of corn producers willing to sell and transport corn stover to collection facilities. (author)

  13. Steam explosion enhances digestibility and fermentation of corn stover by facilitating ruminal microbial colonization.

    Science.gov (United States)

    Zhao, Shengguo; Li, Guodong; Zheng, Nan; Wang, Jiaqi; Yu, Zhongtang

    2018-04-01

    The purpose of this study was to evaluate steam explosion as a pretreatment to enhance degradation of corn stover by ruminal microbiome. The steam explosion conditions were first optimized, and then the efficacy of steam explosion was evaluated both in vitro and in vivo. Steam explosion altered the physical and chemical structure of corn stover as revealed by scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) spectroscopy, respectively, and increased its cellulose content while decreasing hemicellulose content. Steam-exploded corn stover also increased release of reducing sugars, rate of fermentation, and production of volatile fatty acids (VFAs) in vitro. The steam explosion treatment increased microbial colonization and in situ degradation of cellulose and hemicellulose of corn stover in the rumen of dairy cows. Steam explosion may be a useful pretreatment of corn stover to improve its nutritional value as forage for cattle, or as feedstock for biofuel production. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Ash Reduction of Corn Stover by Mild Hydrothermal Preprocessing

    Energy Technology Data Exchange (ETDEWEB)

    M. Toufiq Reza; Rachel Emerson; M. Helal Uddin; Garold Gresham; Charles J. Coronella

    2014-04-22

    Lignocellulosic biomass such as corn stover can contain high ash content, which may act as an inhibitor in downstream conversion processes. Most of the structural ash in biomass is located in the cross-linked structure of lignin, which is mildly reactive in basic solutions. Four organic acids (formic, oxalic, tartaric, and citric) were evaluated for effectiveness in ash reduction, with limited success. Because of sodium citrate’s chelating and basic characteristics, it is effective in ash removal. More than 75 % of structural and 85 % of whole ash was removed from the biomass by treatment with 0.1 g of sodium citrate per gram of biomass at 130 °C and 2.7 bar. FTIR, fiber analysis, and chemical analyses show that cellulose and hemicellulose were unaffected by the treatment. ICP–AES showed that all inorganics measured were reduced within the biomass feedstock, except sodium due to the addition of Na through the treatment. Sodium citrate addition to the preconversion process of corn stover is an effective way to reduced physiological ash content of the feedstock without negatively impacting carbohydrate and lignin content.

  15. 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.

  16. Microbial pretreatment of corn stovers by solid-state cultivation of Phanerochaete chrysosporium for biogas production.

    Science.gov (United States)

    Liu, Shan; Wu, Shubiao; Pang, Changle; Li, Wei; Dong, Renjie

    2014-02-01

    The microbial pretreatment of corn stover and corn stover silage was achieved via the solid-state cultivation of Phanerochaete chrysosporium; pretreatment effects on the biodegradability and subsequent anaerobic production of biogas were investigated. The peak levels of daily biogas production and CH₄ yield from corn stover silage were approximately twice that of corn stover. Results suggested that ensiling was a potential pretreatment method to stimulate biogas production from corn stover. Surface morphology and Fourier-transform infrared spectroscopy analyses demonstrated that the microbial pretreatment of corn stover silage improved biogas production by 10.5 to 19.7% and CH4 yield by 11.7 to 21.2% because pretreatment could decrease dry mass loss (14.2%) and increase substrate biodegradability (19.9% cellulose, 32.4% hemicellulose, and 22.6% lignin). By contrast, the higher dry mass loss in corn stover (55.3%) after microbial pretreatment was accompanied by 54.7% cellulose, 64.0% hemicellulose, and 61.1% lignin degradation but did not significantly influence biogas production.

  17. 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

  18. Study on the Effect of cellulolytic strain MYB3 for Corn Stover Fermentation

    Science.gov (United States)

    Yan, Han; Bai, Bing; Cheng, Xiao-Xiao; Li, Guang-Chun; Huang, Shi-Chen; Piao, Chun-Xiang

    2018-03-01

    The effects of corn stover fermentation with the Bacillus megaterium MYB3 was studied in this paper. The results showed that the decomposition rates of cellulose and hemicellulose were 49.6%, 43.46% after 20 days respectively, after fermentation, pH was changed to 5.68, and adjusted to corn stover initial pH 3 to achieve the purpose of sterilization. The decomposition rate was significantly increased by adding corn flour. After adjusting fermentation composes with the ratio of the corn stove to corn flour was 15 : 1, the decomposition rate of cellulose would be 52.37% for 10 days.

  19. 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

  20. Catalytic and atmospheric effects on microwave pyrolysis of corn stover.

    Science.gov (United States)

    Huang, Yu-Fong; Kuan, Wen-Hui; Chang, Chi-Cheng; Tzou, Yu-Min

    2013-03-01

    Corn stover, which is one of the most abundant agricultural residues around the world, could be converted into valuable biofuels and bio based products by means of microwave pyrolysis. After the reaction at the microwave power level of 500W for the processing time of 30min, the reaction performance under N2 atmosphere was generally better than under CO2 atmosphere. This may be due to the better heat absorbability of CO2 molecules to reduce the heat for stover pyrolysis. Most of the metal-oxide catalysts effectively increased the maximum temperature and mass reduction ratio but lowered the calorific values of solid residues. The gas most produced was CO under N2 atmosphere but CO2 under CO2 atmosphere. Catalyst addition lowered the formation of PAHs and thus made liquid products less toxic. More liquid products and less gas products were generated when using the catalysts possibly due to the existence of the Fischer-Tropsch synthesis. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Corn stover for advanced biofuels perspectives of a soil “Lorax”

    Science.gov (United States)

    Crop residues like corn (Zea Mays L) stover are potential feedstock for production of advanced biofuels (e.g., cellulosic ethanol). Utilization of residue like stover for biofuel feedstock may provide economic and greenhouse gas mitigation benefits; however, harvesting these materials must be done i...

  2. 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...

  3. 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.

  4. Impact of recycling stillage on conversion of dilute sulfuric acid pretreated corn stover to ethanol.

    Science.gov (United States)

    Mohagheghi, Ali; Schell, Daniel J

    2010-04-01

    Both the current corn starch to ethanol industry and the emerging lignocellulosic biofuels industry view recycling of spent fermentation broth or stillage as a method to reduce fresh water use. The objective of this study was to understand the impact of recycling stillage on conversion of corn stover to ethanol. Sugars in a dilute-acid pretreated corn stover hydrolysate were fermented to ethanol by the glucose-xylose fermenting bacteria Zymomonas mobilis 8b. Three serial fermentations were performed at two different initial sugar concentrations using either 10% or 25% of the stillage as makeup water for the next fermentation in the series. Serial fermentations were performed to achieve near steady state concentration of inhibitors and other compounds in the corn stover hydrolysate. Little impact on ethanol yields was seen at sugar concentrations equivalent to pretreated corn stover slurry at 15% (w/w) with 10% recycle of the stillage. However, ethanol yields became progressively poorer as the sugar concentration increased and fraction of the stillage recycled increased. At an equivalent corn stover slurry concentration of 20% with 25% recycled stillage the ethanol yield was only 5%. For this microorganism with dilute-acid pretreated corn stover, recycling a large fraction of the stillage had a significant negative impact on fermentation performance. Although this finding is of concern for biochemical-based lignocellulose conversion processes, other microorganism/pretreatment technology combinations will likely perform differently. (c) 2009 Wiley Periodicals, Inc.

  5. Effect of steam explosion and microbial fermentation on cellulose and lignin degradation of corn stover.

    Science.gov (United States)

    Chang, Juan; Cheng, Wei; Yin, Qingqiang; Zuo, Ruiyu; Song, Andong; Zheng, Qiuhong; Wang, Ping; Wang, Xiao; Liu, Junxi

    2012-01-01

    In order to increase nutrient values of corn stover, effects of steam explosion (2.5 MPa, 200 s) and Aspergillus oryzae (A. oryzae) fermentation on cellulose and lignin degradation were studied. The results showed the contents of cellulose, hemicellulose and lignin in the exploded corn stover were 8.47%, 50.45% and 36.65% lower than that in the untreated one, respectively (Pcellulose and hemicellulose in the exploded and fermented corn stover (EFCS) were decreased by 24.36% and 69.90%, compared with the untreated one (Pcorn stover. The activities of enzymes in EFCS were increased. The metabolic experiment showed that about 8% EFCS could be used to replace corn meal in broiler diets, which made EFCS become animal feedstuff possible. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Kinetic study of dilute nitric acid treatment of corn stover at relatively high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, R.; Lu, X.; Liu, Y.; Wang, X.; Zhang, S. [Tianjin University, School of Environmental Science and Technology, Tianjin (China)

    2011-03-15

    Corn stover was hydrolyzed using dilute nitric acid at 150 C. Several concentrations of HNO{sub 3} (0.2, 0.4 and 0.6 wt-%) and reaction times (0-60 min) were evaluated. The kinetic parameters of mathematical models for predicting the concentrations of xylose, glucose, arabinose, acetic acid, and furfural in the hydrolysates were determined. The hydrolysates obtained from corn stover can be used to produce methane by an anaerobic fermentation process. Thus, the hydrolysis process of corn stover using dilute nitric acid can be conceived as the first stage of an integrated strategy for corn stover utilization. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

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

    KAUST Repository

    Wang, Xin; Feng, Yujie; Wang, Heming; Qu, Youpeng; Yu, Yanling; Ren, Nanqi; Li, Nan; Wang, Elle; Lee, He; Logan, Bruce E.

    2009-01-01

    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

  8. 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...

  9. 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...... and liquors were investigated. The results indicate that there was no detectable arabinan left in the WIS when the acetic acid of 0.1 and 0.2 g g−1 corn stover were used in the pretreatment. The arabinan contents in the other WISs were not more than 10%. However, the arabinan found in the liquors...... was not covering the amount of arabinan released from the raw corn stover. For the arabinan recovery from liquor fractions, the highest of 43.57% was obtained by the pretreatment of acetic acid of 0.01 g g−1 of corn stover and the lowest was only 26.77% when the acetic acid of 0.2 g g−1 corn stover was used...

  10. Detoxification of corn stover and corn starch pyrolysis liquors by ligninolytic enzymes of Phanerochaete chrysosporium.

    Science.gov (United States)

    Khiyami, Mohammad A; Pometto, Anthony L; Brown, Robert C

    2005-04-20

    Phanerochaete chrysosporium (ATCC 24725) shake flask culture with 3 mM veratryl alcohol addition on day 3 was able to grow and detoxify different concentrations of diluted corn stover (Dcs) and diluted corn starch (Dst) pyrolysis liquors [10, 25, and 50% (v/v)] in defined media. GC-MS analysis of reaction products showed a decrease and change in some compounds. In addition, the total phenolic assay with Dcs samples demonstrated a decrease in the phenolic compounds. A bioassay employing Lactobacillus casei growth and lactic acid production was developed to confirm the removal of toxic compounds from 10 and 25% (v/v) Dcs and Dst by the lignolytic enzymes, but not from 50% (v/v) Dcs and Dst. The removal did not occur when sodium azide or cycloheximide was added to Ph. chrysosporium culture media, confirming the participation of lignolytic enzymes in the detoxification process. A concentrated enzyme preparation decreased the phenolic compounds in 10% (v/v) corn stover and corn starch pyrolysis liquors to the same extent as the fungal cultures.

  11. An energy analysis of ethanol from cellulosic feedstock. Corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Lin; Van der Voet, Ester; Huppes, Gjalt [Institute of Environmental Sciences (CML), Leiden University, P.O. Box 9518, 2300 RA, Leiden (Netherlands)

    2009-10-15

    The shift from fossil resources to renewables for energy and materials production has been the driving force for research on energy analysis and environmental impact assessment of bio-based production. This study presents a detailed energy analysis of corn stover based ethanol production using advanced cellulosic technologies. The method used differs from that in LCA and from major studies on the subject as published in Science in two respects. First, it accounts for all the co-products together and so mainly avoids the allocation problems which plague all LCA studies explicitly and other studies implicitly. Second, the system boundaries only involve the content of the energy products used in the system but not the production processes of these energy products, like refining and electricity production. We normalized the six Science studies to this unified method. The resulting values of the total energy product use in both agricultural production and biomass conversion to ethanol are lower than these literature values. LCA-type of values including energy conversion would systematically be higher, in our case study around 45%. The net energy value of cellulosic ethanol production is substantially higher than the ones of the corn-based technologies, and it is similar to incineration and gasification for electricity production. The detailed analysis of energy inputs indicates opportunities to optimize the system. This form of energy analysis helps establishing models for the analysis of more complex systems such as biorefineries. (author)

  12. Crop and Soil Responses to Using Corn Stover as a Bioenergy Feedstock: Observations from the Northern US Corn Belt

    Directory of Open Access Journals (Sweden)

    Jane M. F. Johnson

    2013-02-01

    Full Text Available Corn (Zea mays L. stover is a potential bioenergy feedstock, but little is known about the impacts of reducing stover return on yield and soil quality in the Northern US Corn Belt. Our study objectives were to measure the impact of three stover return rates (Full (~7.8 Mg ha−1 yr−1, Moderate (~3.8 Mg ha−1 yr−1 or Low (~1.5 Mg ha yr−1 Return on corn and soybean (Glycine max. L [Merr.] yields and on soil dynamic properties on a chisel-tilled (Chisel field, and well- (NT1995 or newly- (NT2005 established no-till managed fields. Stover return rate did not affect corn and soybean yields except under NT1995 where Low Return (2.88 Mg ha−1 reduced yields compared with Full and Moderate Return (3.13 Mg ha−1. In NT1995 at 0–5 cm depth, particulate organic matter in Full Return and Moderate Return (14.3 g kg−1 exceeded Low Return (11.3 g kg−1. In NT2005, acid phosphatase activity was reduced about 20% in Low Return compared to Full Return. Also the Low Return had an increase in erodible-sized dry aggregates at the soil surface compared to Full Return. Three or fewer cycles of stover treatments revealed little evidence for short-term impacts on crop yield, but detected subtle soil changes that indicate repeated harvests may have negative consequences if stover removed.

  13. 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.

  14. Enhancing biogas production of corn stover by fast pyrolysis pretreatment.

    Science.gov (United States)

    Wang, Fang; Zhang, Deli; Wu, Houkai; Yi, Weiming; Fu, Peng; Li, Yongjun; Li, Zhihe

    2016-10-01

    A new thermo-chemical pretreatment by a lower temperature fast pyrolysis (LTFP) was applied to promote anaerobic digestion (AD) efficiency of corn stover (CS). The pretreatment experiment was performed by a fluidized bed pyrolysis reactor at 180, 200 and 220°C with a carrier gas flow rate of 4 and 3m(3)/h. The components characteristics, Scanning Electron Microscope (SEM) images and Crystal Intensity (CrI) of the pretreated CS were tested to explore effectiveness of the pretreatment. The results showed that the cumulative methane production at 180°C for 4 and 3m(3)/h were 199.8 and 200.3mL/g TS, respectively. As compared to the untreated CS, the LTFP pretreatment significantly (a<0.05) increased the methane production by 18.07% and 18.33%, respectively. Methane production was well fitted by the Gompertz models, and the maximum methane potential and AD efficiency was obtained at 180°C for 3m(3)/h. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. 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

    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...

  16. 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.

  17. Alkaline pretreatment of Mexican pine residues for bioethanol ...

    African Journals Online (AJOL)

    Alkaline pretreatment of Mexican pine residues for bioethanol production. ... Keywords: Lignocellulosic biomass, alkaline pretreatment, enzymatic hydrolysis, fermentable sugars, fermentation. African Journal of Biotechnology Vol. 12(31), pp.

  18. Biological pretreatment of corn stover with ligninolytic enzyme for high efficient enzymatic hydrolysis.

    Science.gov (United States)

    Wang, Feng-Qin; Xie, Hui; Chen, Wei; Wang, En-Tao; Du, Feng-Guang; Song, An-Dong

    2013-09-01

    Aiming at increasing the efficiency of transferring corn stover into sugars, a biological pretreatment was developed and investigated in this study. The protocol was characterized by the pretreatment with crude ligninolytic enzymes from Phanerochete chrysosporium and Coridus versicolor to break the lignin structure in corn stover, followed by a washing procedure to eliminate the inhibition of ligninolytic enzyme on cellulase. By a 2 d-pretreatment, sugar yield from corn stover hydrolysis could be increased by 50.2% (up to 323 mg/g) compared with that of the control. X-ray diffractometry and FT-IR analysis revealed that biological pretreatment could partially remove the lignin of corn stover, and consequently enhance the enzymatic hydrolysis efficiency of cellulose and hemeicellulose. In addition, the amount of microbial inhibitors, such as acetic acid and furfural, were much lower in biological pretreatment than that in acid pretreatment. This study provided a promising pretreatment method for biotransformation of corn stovers. Copyright © 2013 Elsevier Ltd. All rights reserved.

  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. 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.

  1. Combustion of Corn Stover Bales in a Small 146-kW Boiler

    Directory of Open Access Journals (Sweden)

    Joey Villeneuve

    2011-07-01

    Full Text Available Spring harvested corn stover was used for direct combustion in a 146 kW dual chamber boiler designed for wood logs. Stover had a very low moisture content (6.83 ± 0.17%, a gross calorific value (GCV of 18.57 MJ/kg of dry matter (±0.32 MJ/kg DM and an ash content of 5.88% (±1.15%. Small stover bales (8.83 ± 0.90 kg were placed manually in the upper combustion chamber at a rate of 10.5 to 12.8 kg/h over a 24-h period, with three replications, and compared to a control wood combustion trial (12.1 kg/h during 24 h. The overall heat transfer efficiency for stover was lower than for wood (57% vs. 77%. Stover bales produced on average 7.5% ash which included about 2% of unburned residues while wood produced 1.7% ash. CO gas emissions averaged 1324 mg/m³ for stover (118 mg/m³ for wood. The corn stover showed a good calorific potential, but it would have to be densified and the boiler should be modified to improve airflow, completeness of combustion and handling of the large amount of ash formed.

  2. Production, carbon and nitrogen in stover fractions of corn (Zea mays L.) in response to cultivar development

    Science.gov (United States)

    The contribution of genetic selection of corn to quantity and quality of stover is still poor-known. The aim of the study was to evaluate production, C and N in fractions of corn stover in response to the cultivar development. Two field experiments were conducted in the city of Rolândia (Paraná - Br...

  3. Efficient transformation of corn stover to furfural using p-hydroxybenzenesulfonic acid-formaldehyde resin solid acid.

    Science.gov (United States)

    Zhang, Tingwei; Li, Wenzhi; An, Shengxin; Huang, Feng; Li, Xinzhe; Liu, Jingrong; Pei, Gang; Liu, Qiying

    2018-05-24

    In this work, p-hydroxybenzenesulfonic acid-formaldehyde resin acid catalyst (MSPFR), was synthesized by a hydrothermal method, and employed for the furfural production from raw corn stover. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), N 2 adsorption-desorption, elemental analysis (EA), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FT-IR) were used to characterize the MSPFR. The effects of reaction time, temperature, solvents and corn stover loading were investigated. The MSPFR presented high catalytic activity for the formation of furfural from corn stover. When the MSPFR/corn stover mass loading ratio was 0.5, a higher furfural yield of 43.4% could be achieved at 190 °C in 100 min with 30.7% 5-hydroxymethylfurfural (HMF) yield. Additionally, quite importantly, the recyclability of the MSPFR for xylose dehydration is good, and for the conversion of corn stover was reasonable. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. 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.

  5. 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)

  6. Characterization of corn stover, distiller grains and cattle manure for thermochemical conversion

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lijun; Shahbazi, Abolghasem [Department of Natural Resources and Environmental Design, North Carolina Agricultural and Technical State University, Greensboro, NC 27411 (United States); Hanna, Milford A. [Industrial Agricultural Products Center, Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE 68583-0726 (United States)

    2011-01-15

    Corn stover, distiller grains and cattle manure were characterized to evaluate their acceptability for thermochemical conversion. The energy densities of ground corn stover, distiller grains and cattle manure after totally drying were 3402, 11,813 and 10,374 MJ/m{sup 3}, compared to 37,125 MJ/m{sup 3} for coal. The contents of volatiles in corn stover, distiller grains and cattle manure were 77.4, 82.6 and 82.8%, respectively, on a dry and ash-free basis compared to 43.6% for coal. About 90% of the volatiles in corn stover, distiller grains and cattle manure were released at pyrolysis temperatures of 497, 573 and 565 C, respectively. The combustion of corn stover, distiller grains and cattle manure were completed at 620, 840 and 560 C, respectively. The heat values of the biomass and air mixture for stoichiometric combustion were 2.64, 2.75 and 1.77 MJ/kg for dried corn stover, distiller grains and cattle manure, respectively, as compared to 2.69 MJ/kg for coal. Combustion of 1 kg of dry corn stover, distiller grains and cattle manure generated 5.33, 6.20 and 5.66 Nm{sup 3} of flue gas, respectively, compared to 8.34 Nm{sup 3} for coal. Simulation showed that gasification of 1 kg of dried corn stover, distiller grains and cattle manure at 850 C and ER of 0.3 generated 2.02, 2.37 and 1.44 Nm{sup 3} dry syngas at a heating value of about 4.5 MJ/Nm{sup 3}, compared to 3.52 Nm{sup 3} at 5.8 MJ/Nm{sup 3} for coal. The molecular ratio of H{sub 2} to CO in the biomass-derived syngas was close to 1.0, compared to about 0.5 for the coal-derived syngas. (author)

  7. 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.

  8. 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.

  9. 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

  10. Process development of short-chain polyols synthesis from corn stover by combination of enzymatic hydrolysis and catalytic hydrogenolysis

    Directory of Open Access Journals (Sweden)

    Zhen-Hong Fang

    2014-09-01

    Full Text Available Currently short-chain polyols such as ethanediol, propanediol, and butanediol are produced either from the petroleum feedstock or from the starch-based food crop feedstock. In this study, a combinational process of enzymatic hydrolysis with catalytic hydrogenolysis for short-chain polyols production using corn stover as feedstock was developed. The enzymatic hydrolysis of the pretreated corn stover was optimized to produce stover sugars at the minimum cost. Then the stover sugars were purified and hydrogenolyzed into polyols products catalyzed by Raney nickel catalyst. The results show that the yield of short-chain polyols from the stover sugars was comparable to that of the corn-based glucose. The present study provided an important prototype for polyols production from lignocellulose to replace the petroleum- or corn-based polyols for future industrial applications.

  11. Assessment of Options for the Collection, Handling, and Transport of Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Perlack, R.D.

    2002-11-18

    In this report, we discuss the logistics and estimate the delivered costs for collecting, handling, and hauling corn stover to an ethanol conversion facility. We compare costs for two conventional baling systems (large round bales and large rectangular bales), a silage-harvest system, and an unprocessed-pickup system. Our results generally indicate that stover can be collected, stored, and hauled for about $43.60 to $48.80/dry ton ($48.10-$53.80/dry Mg) using conventional baling equipment for conversion facilities ranging in size from 500 to 2000 dry tons/day (450-1810 dry Mg/day). These estimates are inclusive of all costs including farmer payments for the stover. Our results also suggest that costs might be significantly reduced with an unprocessed stover pickup system provided more efficient equipment is developed.

  12. 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.

  13. 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

  14. 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

  15. Assesment of PM2.5 emission from corn stover burning determining in chamber combustion

    Science.gov (United States)

    Hafidawati; Lestari, P.; Sofyan, A.

    2018-04-01

    Chamber measurement were conducted to determine Particulate Matter (PM2.5) emission from open burning of corn straw at Garut District, West Java. The of this study is to estimate the concentration of PM2.5 for two types of corn (corncobs and cornstover) for five varieties (Bisma, P29, NK, Bisma, NW). Corn residues were collected and then burned in the chamber combustion. The chamber was designed to simulate the burning in the field, which was observed in the field experiment that meteorological condition was calm wind. The samples were collected using a minivol air sampler. The assessment results of PM2.5 concentrations (mg/m3) from open burning experiment in the chamber for five varieties of corn cobs (Bisma, P29, NK, Bisi, NW) was 9.187; 2.843; 7.409; 3.781; 1.895 respectively. Concentration for corn stover burn was 2.060; 5.283; 4.048; 5.306 and 5.697 respectively. Fluctuations in the value of concentration among these varieties reflect variations in combustion conditions (combustion efficiency) and other parameters including water content, biomass conditions and the meteorological conditions. The combustion efficiency (MCE) of the combustion chamber simulation of corncobs ia lower than the MCE of corn stover, that the concentration PM2.5 more emitted from the burning of corn stover. The results of this study presented provide useful information for the development of local emission factors for PM2.5 from open burning of corn stover in Indonesia.

  16. Compression Characteristics and Energy Requirement of Briquettes Made from a Mixture of Corn Stover and Peanut Shells

    Directory of Open Access Journals (Sweden)

    Chunxiao Gong

    2015-07-01

    Full Text Available Corn stover and peanut shells are both abundantly available biomass feedstocks in China. To determine the compression characteristics and energy requirement of briquettes, mixtures of the corn stover and peanut shells were compressed under three different pressures (30, 60, and 90 MPa with three moisture contents (9%, 14%, and 19%, wet basis and five corn stover-peanut shell mixtures (0%-100%, 25%-75%, 50%-50%, 75%-25%, and 100%-0% by mass. The results showed that applied pressure, moisture content, and the corn stover-peanut shell mixture all significantly affected briquette density and specific energy consumption. The density of the briquette ranged from 646 to 1052 kg/m3 and the specific energy consumption varied from 6.6 to 25.1 MJ/t. A moisture content of 9% was found to be better for the compression of the corn stover and peanut shells mixture. Adding peanut shells to the corn stover improved briquette density and reduced the specific energy consumption. Linear models were developed to describe the briquette density and the specific energy consumption. The briquette durability ranged from 57% to 94% and durable briquettes can be obtained when corn stover and peanut shells are compressed with the mixing ratio of 1:1 (50%-50% at moisture content of 9%.

  17. Influence of different SSF conditions on ethanol production from corn stover at high solids loadings

    DEFF Research Database (Denmark)

    Gladis, Arne; Bondesson, Pia-Maria; Galbe, Mats

    2015-01-01

    In this study, three different kinds of simultaneous saccharification and fermentation (SSF) of washed pretreated corn stover with water-insoluble solids (WIS) content of 20% were investigated to find which one resulted in highest ethanol yield at high-solids loadings. The different methods were...

  18. 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...

  19. Pretreatment of corn stover using wet oxidation to enhance enzymatic digestibility.

    Science.gov (United States)

    Varga, Eniko; Schmidt, Anette S; Réczey, Kati; Thomsen, Anne Belinda

    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) was investigated to enhance the enzymatic digestibility of corn stover. Six different combinations of reaction temperature, time, and pH were applied. The best conditions (60 g/L of corn stover, 195 degrees C, 15 min, 12 bar O2, 2 g/L of Na2CO3) increased the enzymatic conversion of corn stover four times, compared to untreated material. Under these conditions 60% of hemicellulose and 30% of lignin were solubilized, whereas 90% of cellulose remained in the solid fraction. After 24-h hydrolysis at 50 degrees C using 25 filter paper units (FPU)/g of drymatter (DM) biomass, the achieved conversion of cellulose to glucose was about 85%. Decreasing the hydrolysis temperature to 40 degrees C increased hydrolysis time from 24 to 72 h. Decreasing the enzyme loading to 5 FPU/g of DM biomass slightly decreased the enzymatic conversion from 83.4 to 71%. Thus, enzyme loading can be reduced without significantly affecting the efficiency of hydrolysis, an important economical aspect.

  20. 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.

  1. 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...

  2. Is Corn Stover Harvest Predictable Using Farm Operation, Technology, and Management Variables?

    Science.gov (United States)

    Crop residue management, provision of animal feed or bedding, and increased income potential are some reasons for harvesting corn (Zea mays L.) stover. Reasons for not doing so are that crop residue is essential for restoring soil organic matter, protecting against wind and water erosion, and cyclin...

  3. Corn stover lignin is modified differently by acetic acid compared to sulfuric acid

    NARCIS (Netherlands)

    Mouthier, Thibaut; Appeldoorn, Maaike M.; Pel, Herman; Schols, Henk A.; Gruppen, Harry; Kabel, Mirjam A.

    2018-01-01

    In this study, two acid catalysts, acetic acid (HAc) and sulfuric acid (H2SO4), were compared in thermal pretreatments of corn stover, in particular to assess the less understood fate of lignin. HAc-insoluble lignin, analyzed by pyrolysis GC–MS, showed decreasing levels (%) of Cα-oxidized (from 3.7

  4. High temperature dilute phosphoric acid pretreatment of corn stover for furfural and ethanol production

    Science.gov (United States)

    Furfural was produced from corn stover by one stage pretreatment process using dilute H3PO4 and solid residues following furfural production were used for ethanol production by Saccharomyces cerevisiae NRRL- Y2034. A series of experiments were conducted at varied temperatures (140-200 oC) and acid ...

  5. Ammonia, total reduced sulfides, and greenhouse gases of pine chip and corn stover bedding packs

    Science.gov (United States)

    Bedding materials may affect air quality in livestock facilities. The objective of this study was to compare headspace concentrations of ammonia (NH3), total reduced sulfides (TRS), carbon dioxide (CO2),methane (CH4), and nitrous oxide (N2O) when pine wood chips and corn stover were mixed in various...

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. 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.

  12. 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%.

  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, 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.

  14. Comparison of Chemical Composition and Energy Property of Torrefied Switchgrass and Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Tumuluru, Jaya Shankar, E-mail: jayashankar.tumuluru@inl.gov [Idaho National Laboratory, Idaho Falls, ID (United States)

    2015-11-30

    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.

  15. 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.

  16. 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.

  17. Promoting anaerobic biogasification of corn stover through biological pretreatment by liquid fraction of digestate (LFD).

    Science.gov (United States)

    Hu, Yun; Pang, Yunzhi; Yuan, Hairong; Zou, Dexun; Liu, Yanping; Zhu, Baoning; Chufo, Wachemo Akiber; Jaffar, Muhammad; Li, Xiujin

    2015-01-01

    A new biological pretreatment method by using liquid fraction of digestate (LFD) was advanced for promoting anaerobic biogasification efficiency of corn stover. 17.6% TS content and ambient temperature was appropriate for pretreatment. The results showed that C/N ratio decreased to about 30, while total lignin, cellulose, and hemicellulose (LCH) contents were reduced by 8.1-19.4% after pretreatment. 3-days pretreatment was considered to be optimal, resulting in 70.4% more biogas production, 66.3% more biomethane yield and 41.7% shorter technical digestion time compared with the untreated stover. The reductions on VS, cellulose, and hemicellulose were increased by 22.1-35.9%, 22.3-35.4%, and 19.8-27.2% for LFD-treated stovers. The promoted anaerobic biogasification efficiency was mainly attributed to the improved biodegradability due to the pre-decomposition role of the bacteria in LFD. The method proved to be an efficient and low cost approach for producing bioenergy from corn stover, meanwhile, reducing LFD discharge and minimizing its potential pollution. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. 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.

  19. 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.

  20. A new magnesium bisulfite pretreatment (MBSP) development for bio-ethanol production from corn stover.

    Science.gov (United States)

    Yu, Heng; Ren, Jiwei; Liu, Lei; Zheng, Zhaojuan; Zhu, Junjun; Yong, Qiang; Ouyang, Jia

    2016-01-01

    This study established a new more neutral magnesium bisulfate pretreatment (MBSP) using magnesium bisulfate as sulfonating agent for improving the enzymatic hydrolysis efficiency of corn stover. Using the MBSP with 5.21% magnesium bisulfate, 170°C and pH 5.2 for 60 min, about 90% of lignin and 80% of hemicellulose were removed from biomass and more than 90% cellulose conversion of substrate was achieved after 48 h hydrolysis. About 6.19 kg raw corn stover could produce 1 kg ethanol by Saccharomyces cerevisiae. Meanwhile, MBSP also could protect sugars from excessive degradation, prevent fermentation inhibition formation and directly convert the hemicelluloses into xylooligosaccharides as higher-value products. These results suggested that the MBSP method offers an alternative approach to the efficient conversion of nonwoody lignocellulosic biomass to ethanol and had broad space for development. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Fermentation of Acid-pretreated Corn Stover to Ethanol Without Detoxification Using Pichia stipitis

    Science.gov (United States)

    Agbogbo, Frank K.; Haagensen, Frank D.; Milam, David; Wenger, Kevin S.

    In this work, the effect of adaptation on P. stipitis fermentation using acidpretreated corn stover hydrolyzates without detoxification was examined. Two different types of adaptation were employed, liquid hydrolyzate and solid state agar adaptation. Fermentation of 12.5% total solids undetoxified acid-pretreated corn stover was performed in shake flasks at different rotation speeds. At low rotation speed (100 rpm), both liquid hydrolyzate and solid agar adaptation highly improved the sugar consumption rate as well as ethanol production rate compared to the wild-type strains. The fermentation rate was higher for solid agar-adapted strains compared to liquid hydrolyzate-adapted strains. At a higher rotation speed (150 rpm), there was a faster sugar consumption and ethanol production for both the liquid-adapted and the wild-type strains. However, improvements in the fermentation rate between the liquid-adapted and wild strains were less pronounced at the high rotation speed.

  2. 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.

  3. 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.

  4. 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-...

  5. 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...

  6. Hydrolysis of alkaline pretreated banana peel

    Science.gov (United States)

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

    2017-11-01

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

  7. Dynamic Analysis of Bioethanol Production from Corn Stover and Immobilized Yeast

    Directory of Open Access Journals (Sweden)

    Shuang-Qi Tian

    2016-05-01

    Full Text Available The use of low cost and abundant corn stover in yeast fermentation can reduce product costs. In this study, bioethanol was produced from a hydrolysate of corn stover using immobilized yeast. A kinetic model was established for the total reducing sugar consumption and the production of bioethanol. The parameter estimation for kinetic modeling considered the main process variables during bioethanol production from corn stover. Total reducing sugar concentrations decreased exponentially in the bioethanol fermentation for 6 h; consumption was more than 90%. To use kinetic modelling of yeast growth for bioethanol fermentation, the value of μmax reached 0.2891 h-1, and the matrix inhibition constant (KIS and production inhibition constant (KIP were 8.9154 g/dm3 and 0.00676 g/dm3, respectively. To use kinetic modelling of fermentation time on bioethanol, the maximum ratio of bioethanol production rate (qmax reached 1.427 g/g•L. However, KIS was 2.813 g/dm3, and KIP was 0.0149 g/dm3.

  8. 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

    was about 85%. Decreasing the hydrolysis temperature to 40degreesC increased hydrolysis time from 24 to 72 h. Decreasing the enzyme loading to 5 FPU/g of DM biomass slightly decreased the enzymatic conversion from 83.4 to 71%. Thus, enzyme loading can be reduced without significantly affecting......) was investigated to enhance the enzymatic digestibility of corn stover. Six different combinations of reaction temperature, time, and pH were applied. The best conditions (60 g/L of corn stover, 195degreesC, 15 min, 12 bar O-2, 2 g/L of Na2CO) increased the enzymatic conversion of corn stover four times, compared...... to untreated material. Under these conditions 60% of hemicellulose and 30% of lignin were solubilized, whereas 90% of cellulose remained in the solid fraction. After 24-h hydrolysis at 50degreesC using 25 filter paper units (FPU)/g of drymatter (DM) biomass, the achieved conversion of cellulose to glucose...

  9. Enhanced biohydrogen production from corn stover by the combination of Clostridium cellulolyticum and hydrogen fermentation bacteria.

    Science.gov (United States)

    Zhang, Shou-Chi; Lai, Qi-Heng; Lu, Yuan; Liu, Zhi-Dan; Wang, Tian-Min; Zhang, Chong; Xing, Xin-Hui

    2016-10-01

    Hydrogen was produced from steam-exploded corn stover by using a combination of the cellulolytic bacterium Clostridium cellulolyticum and non-cellulolytic hydrogen-producing bacteria. The highest hydrogen yield of the co-culture system with C. cellulolyticum and Citrobacter amalonaticus reached 51.9 L H2/kg total solid (TS). The metabolites from the co-culture system were significantly different from those of the mono-culture systems. Formate, which inhibits the growth of C. cellulolyticum, could be consumed by the hydrogen-evolving bacteria, and transformed into hydrogen. Glucose and xylose were released from corn stover via hydrolysis by C. cellulolyticum and were quickly utilized in dark fermentation with the co-cultured hydrogen-producing bacteria. Because the hydrolysis of corn stover by C. cellulolyticum was much slower than the utilization of glucose and xylose by the hydrogen-evolving bacteria, the sugar concentrations were always maintained at low levels, which favored a high hydrogen molar yield. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  10. Enhanced glucose yield and structural characterization of corn stover by sodium carbonate pretreatment.

    Science.gov (United States)

    Kim, Ilgook; Rehman, Muhammad Saif Ur; Han, Jong-In

    2014-01-01

    Na2CO3 was employed as an efficient yet cheap alkaline catalyst for the pretreatment of corn stover. To systematically obtain an optimal condition, the effects of critical pretreatment parameters including Na2CO3 concentration (2-6%), temperature (120-160 °C), and reaction time (10-30 min) on glucose yield were evaluated in lab-scale using response surface methodology. The best conditions were found to be Na2CO3 of 4.1%, temperature of 142.6 °C, and reaction time of 18.0 min, under which glucose yield reached to 267.5 g/kg biomass. Physical properties, based on scanning electron microscopy (SEM) imagery, surface area, pore volume and size, and crystallinity of pretreated corn stover, were examined. The Na2CO3 pretreatment apparently damaged the surface and altered structural features of corn stover, which resulted in the enhancement of enzymatic of hydrolysis. These results evidently support that Na2CO3 is indeed a robust and feasible catalyst for pretreating lignocellulosic biomass. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. 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.

  12. Evaluating fuel ethanol feedstocks from energy policy perspectives: A comparative energy assessment of corn and corn stover

    International Nuclear Information System (INIS)

    Lavigne, Amanda; Powers, Susan E.

    2007-01-01

    Concerns surrounding the continued, un-checked use of petroleum-based fuels in the transportation sector, the search for more sustainable, renewable alternatives, and the constraints of the existing supply infrastructure in the United States have placed a spotlight on biomass-derived fuels. The central question of the ethanol debate has changed from 'Should we make ethanol?' to 'From what should we make ethanol?' emphasizing the importance of understanding the differences between specific biomass supply systems for fuel ethanol. When presented with numerous options, the priorities of an individual decision maker will define which feedstock alternative is the most appropriate choice for development from their perspective. This paper demonstrates how energy data can be successfully used to quantify assessment metrics beyond a standard net energy value calculation, thus quantifying the relative 'value' of ethanol supply systems. This value is defined based on decision-maker priorities that were adopted from national energy policy priorities: increased national energy security and increased conservation of energy resources. Nine energy assessment metrics that quantify detailed system energy data are calculated and a straightforward comparative assessment is performed between corn and corn stover feedstocks produced under the same farm scenario. Corn stover is shown to be more compatible with the national energy policy priorities and it is recommended that additional research be performed on utilizing this feedstock from the corn farm

  13. 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.

  14. 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.

  15. Updates to the Corn Ethanol Pathway and Development of an Integrated Corn and Corn Stover Ethanol Pathway in the GREET™ Model

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhichao [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Wang, Michael Q. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division

    2014-09-01

    Corn ethanol, a first-generation biofuel, is the predominant biofuel in the United States. In 2013, the total U.S. ethanol fuel production was 13.3 billion gallons, over 95% of which was produced from corn (RFA, 2014). The 2013 total renewable fuel mandate was 16.6 billion gallons according to the Energy Independence and Security Act (EISA) (U.S. Congress, 2007). Furthermore, until 2020, corn ethanol will make up a large portion of the renewable fuel volume mandated by Renewable Fuels Standard (RFS2). For the GREET1_2014 release, the corn ethanol pathway was subject to updates reflecting changes in corn agriculture and at corn ethanol plants. In the latter case, we especially focused on the incorporation of corn oil as a corn ethanol plant co-product. Section 2 covers these updates. In addition, GREET now includes options to integrate corn grain and corn stover ethanol production on the field and at the biorefinery. These changes are the focus of Section 3.

  16. 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.

  17. Enhancement of enzymatic hydrolysis of corn stover by γ-irradiation and combined solvent delignification/acid prehydrolysis

    International Nuclear Information System (INIS)

    Nghiem, N.P.; Gonzales-Valdes, A.; Moo-Young, M.; Robinson, C.W.

    1984-01-01

    Two pretreatment schemes were studied for their effect on the enhancement of soluble sugar production from corn stover by enzymatic hydrolysis. In the first scheme, prior to enzymic hydrolysis corn stover which was ground to pass a 1 mm screen was immersed in NaOH solution and exposed to gamma irradiation. The NaOH levels and radiation dosages were varied from 0 to 0.51 gNaOH/g corn stover and from 50 to 150 Mr, respectively. The combined residue and solubles were then hydrolyzed with a commercial cellulase (Onozuka) in 0.05 M citrate buffer at pH 4.6 and 39 0 C for 48 hours. The highest sugar yield of 96% based on the total carbohydrate content of the original sample was obtained at 100 Mr and 0.06 gNaOH/g corn stover. In the second scheme, corn stover which was ground to pass a 0.35 mm screen was delignified with ethanol-water-NaOH. The ethanol-water mixture used contained 3 parts (by volume) of 95% ethanol and 4 g NaOH/L; substrate concentration was 5% (w/v). The delignification was carried out at 140 0 C for 1 hour. At these conditions, 65% of the lignin was removed while 90% of the carbohydrates remained insoluble. The delignified corn stover with an without treatment using 2% wt.% H 2 SO 4 at 95 0 C and 1 hour was then enzymically hydrolyzed with Novo Cellulclast at pH 4.8 and 50 0 C for up to 48 hours. Factors that affect the overall sugar production are presented and discussed. In addition, the overall sugar yields for the two schemes are compared with other pretreatment schemes reported. (orig.)

  18. Fractionation for further conversion: from raw corn stover to lactic acid

    OpenAIRE

    Ting He; Zhicheng Jiang; Ping Wu; Jian Yi; Jianmei Li; Changwei Hu

    2016-01-01

    Fractionation is considered to be one promising strategy to utilize raw biomass to its fullest and produce chemicals with high selectivity. Herein, ethanol/H2O (1/1, v/v) co-solvent with 0.050?M oxalic acid is used to simultaneously fractionate 88.0?wt% of hemicellulose and 89.2?wt% of lignin in corn stover, while cellulose is not obviously degraded. H2O dissolves hemicellulose, G unit and those with ?-O-4 linkage of lignin; whereas ethanol extracts G and S units as well as the skeleton with ...

  19. 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...... 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. (C) 2004 Wiley Periodicals, Inc....

  20. 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....../desorption at 77 K. The results demonstrated that higher specific surface areas of activated carbons were obtained by microwave pyrolysis combined with potassium hydroxide activation. However, electrochemical measurements showed that the slow pyrolysis biochar treated with 0.05 mol g−1 (potassium hydroxide...

  1. 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

  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. Impact of Collection Equipment on Ash Variability of Baled Corn Stover Biomass for Bioenergy

    Energy Technology Data Exchange (ETDEWEB)

    William Smith; Jeffery Einerson; Kevin Kenney; Ian J. Bonner

    2014-09-01

    Cost-effective conversion of agricultural residues for renewable energy hinges not only on the material’s quality but also the biorefinery’s ability to reliably measure quality specifications. The ash content of biomass is one such specification, influencing pretreatment and disposal costs for the conversion facility and the overall value of a delivered lot of biomass. The biomass harvest process represents a primary pathway for accumulation of soil-derived ash within baled material. In this work, the influence of five collection techniques on the total ash content and variability of ash content within baled corn stover in southwest Kansas is discussed. The equipment tested included a mower for cutting the corn stover stubble, a basket rake, wheel rake, or shred flail to gather the stover, and a mixed or uniform in-feed baler for final collection. The results showed mean ash content to range from 11.5 to 28.2 % depending on operational choice. Resulting impacts on feedstock costs for a biochemical conversion process range from $5.38 to $22.30 Mg-1 based on the loss of convertible dry matter and ash disposal costs. Collection techniques that minimized soil contact (shred flail or nonmowed stubble) were shown to prevent excessive ash contamination, whereas more aggressive techniques (mowing and use of a wheel rake) caused greater soil disturbance and entrainment within the final baled material. Material sampling and testing were shown to become more difficult as within-bale ash variability increased, creating uncertainty around feedstock quality and the associated costs of ash mitigation.

  4. 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.

  5. Acid hydrolysis of corn stover using hydrochloric acid: Kinetic modeling and statistical optimization

    Directory of Open Access Journals (Sweden)

    Sun Yong

    2014-01-01

    Full Text Available The hydrolysis of corn stover using hydrochloric acid was studied. The kinetic parameters of the mathematical models for predicting the yields of xylose, glucose, furfural and acetic acid were obtained, and the corresponding xylose generation activation energy of 100 kJ/mol was determined. The characterization of corn stover using with different techniques during hydrolysis indicated an effective removal of xylan and the slightly alteration on the structures of cellulose and lignin. A 23five levels Central Composite Design (CCD was used to develop a statistical model for the optimization of process variables including acid concentration, pretreatment temperature and time. The optimum conditions determined by this model were found to be 108ºC for 80 minutes with acid concentration of 5.8%. Under these conditions, the maximised results are the following: xylose 19.93 g/L, glucose 1.2 g/L, furfural 1.5 g/L, acetic acid 1.3 g/L. The validation of the model indicates a good agreement between the experimental results and the predicted values.

  6. 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.

  7. Optimization of enzyme complexes for efficient hydrolysis of corn stover to produce glucose.

    Science.gov (United States)

    Yu, Xiaoxiao; Liu, Yan; Meng, Jiatong; Cheng, Qiyue; Zhang, Zaixiao; Cui, Yuxiao; Liu, Jiajing; Teng, Lirong; Lu, Jiahui; Meng, Qingfan; Ren, Xiaodong

    2015-05-01

    Hydrolysis of cellulose to glucose is the critical step for transferring the lignocellulose to the industrial chemicals. For improving the conversion rate of cellulose of corn stover to glucose, the cocktail of celllulase with other auxiliary enzymes and chemicals was studied in this work. Single factor tests and Response Surface Methodology (RSM) were applied to optimize the enzyme mixture, targeting maximum glucose release from corn stover. The increasing rate of glucan-to-glucose conversion got the higher levels while the cellulase was added 1.7μl tween-80/g cellulose, 300μg β-glucosidase/g cellulose, 400μg pectinase/g cellulose and 0.75mg/ml sodium thiosulphate separately in single factor tests. To improve the glucan conversion, the β-glucosidase, pectinase and sodium thiosulphate were selected for next step optimization with RSM. It is showed that the maximum increasing yield was 45.8% at 377μg/g cellulose Novozyme 188, 171μg/g cellulose pectinase and 1mg/ml sodium thiosulphate.

  8. 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.

  9. Separation and Analysis of Microwave-assisted Liquefied Products of Corn Stover

    Directory of Open Access Journals (Sweden)

    Weihua Xiao

    2014-10-01

    Full Text Available Corn stover was successfully liquefied by microwave heating at 160 °C with ethylene glycol (EG used as the solvent and sulfuric acid as a catalyst. Gas chromatography and mass spectrometry (GC-MS data indicated that methyl esters, including 3-(2-methyl-1,3-doxolane-2-yl propionic acid methyl ester (PAME, levulinic acid isopropyl ester (LAE, methyl laurate, and methyl palmitate were the major degradation compounds, in addition to EG derivatives in the liquefied product of corn stover (LPCS. For high value-added utilization of LPCS, solvent extraction was applied to characterize the components and to separate it into useful fractions. After being dispersed in water, the water-soluble fraction of the LPCS was then extracted with organic solvents, including hexane, chloroform, diethyl ether, and ethyl acetate. Levulinic acid isopropyl ester showed the highest distribution in chloroform and ethyl acetate, while the lowest in hexane and ether. Levulinic acid isopropyl ester was selectively enriched to 28.76% and 43.65% by sequential extraction with chloroform and ethyl acetate, respectively, in accordance with the quantitative analysis.

  10. 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.

  11. Construction of a Bacterial Cellulase Cocktail for Saccharification of Regenerated Cellulose and Pretreated Corn Stover

    Directory of Open Access Journals (Sweden)

    Alei Geng

    2015-09-01

    Full Text Available To apply bacterial cellulases for efficient saccharification of biomass, three Clostridium thermocellum cellulases and a Thermoanaerobacter brockii β-1,4-glucosidase were synthesized in Escherichia coli, and the proportions among them were optimized. When the activities of CelD, CBHA, CBH48Y, and CglT were set at 554, 0.91, 0.91, and 856 mU per assay, respectively, the percent conversion of regenerated cellulose (0.92 g/L reached 80.9% within 24 h at 60 °C without shaking. Meanwhile, the percent conversion of pretreated corn stover (0.62 g/L reached 70.1%. Gradually raising the loads of regenerated cellulose from 0.92 to 4.58 g/L resulted in a linear increase in glucose production from 870 to 3208 μg (R2=0.997, as well as a decrease in the percent conversion from 80.9% to 59.6%. These findings suggested that the cellulase cocktail is efficient in saccharification of regenerated cellulose, as well as pretreated corn stover, and has potential applications in the biofuels industry.

  12. 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.

  13. Biological conversion of biomass to methane corn stover studies. Project report, December 1, 1977-August 1, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Pfeffer, J T; Quindry, G E

    1979-06-01

    A series of experiments was conducted to determine the performance characteristics of the methane fermentation process using corn stover obtained from the University of Illinois farms and processed through four parallel fermenters each having a capacity of 775 liters. A continuous feed system was employed to determine the conversion efficiency. The dewatering characteristics of the effluents and the quality of the liquid and solid residues were determined. The biodegradability of corn stover is low. Data obtained at a fermentation temperature of 59 +-1/sup 0/C show that only 36 percent of the volatile solids are biodegradable. The first order rate constant for this conversion was found to be 0.25 day/sup -1/. Pretreatment with caustic (NaOH) concentration of 0.30 molar (5 g/100 g dry stover) and a temperature of 115/sup 0/C for one hour increased the biodegradable fraction to 71 percent of the volatile solids. The reactor slurries were easily dewatered by both vacuum filtration and centrifugation. Corn stover does not appear to be attractive economically at the present energy prices. At a chemical cost of $154/tonne ($140/ton), the NaOH pretreatment adds approximately $5.2/tonne to the cost of processing the stover. At a methane yield of 0.25 m/sup 3//kg of solids fed, this adds a total cost of $2/100 m/sup 3/ ($0.57/MCF) for this process alone. Addition of stover acquisition costs ($20/dry tonne of stover), total processing costs without gas cleanup ($21/tonne) and residue disposal ($3/tonne of wet cake), the cost of fuel gas would be in the neighborhood of $9.76/GJ ($10.30/10/sup 6/ Btu).This cost excludes all profit, taxes, etc. associated with private financing. Depending upon financing methods, tax incentives, etc., it may be necessary to add up to an additional $2.00/GJ to the cost of this fuel gas.

  14. 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.

  15. The impact of corn stover removal on N2O emission and soil respiration: An investigation with automated chambers

    Science.gov (United States)

    Corn stover removal, whether for silage, bedding, or bioenergy production, could have a variety of environmental consequences through its effect on soil processes, particularly N2O production and soil respiration. Because these effects may be episodic in nature, weekly snapshots with static chambers...

  16. Direct measures of mechanical energy for knife mill size reduction of switchgrass, wheat straw, and corn stover.

    Science.gov (United States)

    Bitra, Venkata S P; Womac, Alvin R; Igathinathane, C; Miu, Petre I; Yang, Yuechuan T; Smith, David R; Chevanan, Nehru; Sokhansanj, Shahab

    2009-12-01

    Lengthy straw/stalk of biomass may not be directly fed into grinders such as hammer mills and disc refiners. Hence, biomass needs to be preprocessed using coarse grinders like a knife mill to allow for efficient feeding in refiner mills without bridging and choking. Size reduction mechanical energy was directly measured for switchgrass (Panicum virgatum L.), wheat straw (Triticum aestivum L.), and corn stover (Zea mays L.) in an instrumented knife mill. Direct power inputs were determined for different knife mill screen openings from 12.7 to 50.8 mm, rotor speeds between 250 and 500 rpm, and mass feed rates from 1 to 11 kg/min. Overall accuracy of power measurement was calculated to be +/-0.003 kW. Total specific energy (kWh/Mg) was defined as size reduction energy to operate mill with biomass. Effective specific energy was defined as the energy that can be assumed to reach the biomass. The difference is parasitic or no-load energy of mill. Total specific energy for switchgrass, wheat straw, and corn stover chopping increased with knife mill speed, whereas, effective specific energy decreased marginally for switchgrass and increased for wheat straw and corn stover. Total and effective specific energy decreased with an increase in screen size for all the crops studied. Total specific energy decreased with increase in mass feed rate, but effective specific energy increased for switchgrass and wheat straw, and decreased for corn stover at increased feed rate. For knife mill screen size of 25.4 mm and optimum speed of 250 rpm, optimum feed rates were 7.6, 5.8, and 4.5 kg/min for switchgrass, wheat straw, and corn stover, respectively, and the corresponding total specific energies were 7.57, 10.53, and 8.87 kWh/Mg and effective specific energies were 1.27, 1.50, and 0.24 kWh/Mg for switchgrass, wheat straw, and corn stover, respectively. Energy utilization ratios were calculated as 16.8%, 14.3%, and 2.8% for switchgrass, wheat straw, and corn stover, respectively. These

  17. 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)

  18. 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)

  19. Pretreatment combining ultrasound and sodium percarbonate under mild conditions for efficient degradation of corn stover.

    Science.gov (United States)

    Nakashima, Kazunori; Ebi, Yuuki; Kubo, Masaki; Shibasaki-Kitakawa, Naomi; Yonemoto, Toshikuni

    2016-03-01

    Ultrasound (US) can be used to disrupt microcrystalline cellulose to give nanofibers via ultrasonic cavitation. Sodium percarbonate (SP), consisting of sodium carbonate and hydrogen peroxide, generates highly reactive radicals, which cause oxidative delignification. Here, we describe a novel pretreatment technique using a combination of US and SP (US-SP) for the efficient saccharification of cellulose and hemicellulose in lignocellulosic corn stover. Although US-SP pretreatment was conducted under mild condition (i.e., at room temperature and atmospheric pressure), the pretreatment greatly increased lignin removal and cellulose digestibility. We also determined the optimum US-SP treatment conditions, such as ultrasonic power output, pretreatment time, pretreatment temperature, and SP concentration for an efficient cellulose saccharification. Moreover, xylose could be effectively recovered from US-SP pretreated biomass without the formation of microbial inhibitor furfural. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. 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.

  1. 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 a...... material was obtained following pretreatment at 195 °C for 15 min with acetic acid employed. The estimated total ethanol production was 241.1 kg/ton raw material by assuming fermentation of both C-6 and C-5, and 0.51 g ethanol/g sugar....... were performed on liquors obtained from all pretreatments and there were no inhibition effect found in any of the liquors. Simultaneous saccharification and fermentation (SSF) of water-insoluble solids (WIS) showed that a high ethanol yield of 88.7% of the theoretical based on glucose in the raw...

  2. Efficient extraction of xylan from delignified corn stover using dimethyl sulfoxide

    Energy Technology Data Exchange (ETDEWEB)

    Rowley, John; Decker, Stephen R.; Michener, William; Black, Stuart

    2013-09-13

    Xylan can be extracted from biomass using either alkali (KOH or NaOH) or dimethyl sulfoxide (DMSO); however, DMSO extraction is the only method that produces a water-soluble xylan. In this study, DMSO extraction of corn stover was studied at different temperatures with the objective of finding a faster, more efficient extraction method. The temperature and time of extraction were compared followed by a basic structural analysis to ensure that no significant structural changes occurred under different temperatures. The resulting data showed that heating to 70 degrees C during extraction can give a yield comparable to room temperature extraction while reducing the extraction time by ~90 %. This method of heating was shown to be the most efficient method currently available and was shown to retain the important structural characteristics of xylan extracted with DMSO at room temperature.

  3. Environmentally Compatible Synthesis of Superparamagnetic Magnetite (Fe3O4 Nanoparticles with Prehydrolysate from Corn Stover

    Directory of Open Access Journals (Sweden)

    Chunming Zheng

    2013-12-01

    Full Text Available An environmentally compatible and size-controlled method has been employed for synthesis of superparamagnetic magnetite nanoparticles with prehydrolysate from corn stover. Various characterizations involving X-ray diffraction (XRD, standard and high-resolution transmission electron microscopy (TEM and HRTEM, selected area electron diffraction (SAED, and thermogravimetric analysis (TGA have integrally confirmed the formation of magnetite nanoparticles with homogeneous morphology and the formation mechanism of magnetite only from ferric precursor. Organic materials in the prehydrolysate act as a bifunctional agent: (1 a reducing agent to reduce ferric ions to prepare magnetite with the coexistence of ferric and ferrous ions; and (2 a coating agent to prevent particle growth and agglomeration and to promote the formation of nanoscale and superparamagnetic magnetite. The size of the magnetite nanoparticles can be easily controlled by tailoring the reducing sugar concentration, reaction time, or hydrothermal temperature.

  4. Rheology of dilute acid hydrolyzed corn stover at high solids concentration.

    Science.gov (United States)

    Ehrhardt, M R; Monz, T O; Root, T W; Connelly, R K; Scott, C T; Klingenberg, D J

    2010-02-01

    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 temperature, acid concentration, and rheometer temperature. Plastic viscosities increase with increasing solids concentration and tend to decrease with increasing reaction temperature and acid concentration. The solids concentration dependence of the yield stress is consistent with that reported for other fibrous systems. The changes in yield stress with reaction conditions are consistent with observed changes in particle size. This study illustrates that torque rheometry can be used effectively to measure rheological properties of concentrated biomass.

  5. A whole cell biocatalyst for cellulosic ethanol production from dilute acid-pretreated corn stover hydrolyzates

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Seunghyun; Karim, Muhammad Nazmul [Texas Tech Univ., Lubbock, TX (United States). Dept. of Chemical Engineering

    2011-08-15

    In this research, a recombinant whole cell biocatalyst was developed by expressing three cellulases from Clostridium cellulolyticum - endoglucanase (Cel5A), exoglucanase (Cel9E), and {beta}-glucosidase - on the surface of the Escherichia coli LY01. The modified strain is identified as LY01/pRE1H-AEB. The cellulases were displayed on the surface of the cell by fusing with an anchor protein, PgsA. The developed whole cell biocatalyst was used for single-step ethanol fermentation using the phosphoric acid-swollen cellulose (PASC) and the dilute acid-pretreated corn stover. Ethanol production was 3.59 {+-} 0.15 g/L using 10 g/L of PASC, which corresponds to a theoretical yield of 95.4 {+-} 0.15%. Ethanol production was 0.30 {+-} 0.02 g/L when 1 g/L equivalent of glucose in the cellulosic fraction of the dilute sulfuric acid-pretreated corn stover (PCS) was fermented for 84 h. A total of 0.71 {+-} 0.12 g/L ethanol was produced in 48 h when the PCS was fermented in the simultaneous saccharification and co-fermentation mode using the hemicellulosic (1 g/L of total soluble sugar) and as well as the cellulosic (1 g/L of glucose equivalent) parts of PCS. In a control experiment, 0.48 g/L ethanol was obtained from 1 g/L of hemicellulosic PCS. It was concluded that the whole cell biocatalyst could convert both cellulosic and hemicellulosic substrates into ethanol in a single reactor. The developed C. cellulolyticum-E. coli whole cell biocatalyst also overcame the incompatible temperature problem of the frequently reported fungal-yeast systems. (orig.)

  6. 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.

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

    Science.gov (United States)

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

    2010-07-01

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

  8. Efficient production of 2,3-butanediol from corn stover hydrolysate by using a thermophilic Bacillus licheniformis strain.

    Science.gov (United States)

    Li, Lixiang; Li, Kun; Wang, Kai; Chen, Chao; Gao, Chao; Ma, Cuiqing; Xu, Ping

    2014-10-01

    In this study, a thermophilic Bacillus licheniformis strain X10 was newly isolated for 2,3-butanediol (2,3-BD) production from lignocellulosic hydrolysate. Strain X10 could utilize glucose and xylose simultaneously without carbon catabolite repression. In addition, strain X10 possesses high tolerance to fermentation inhibitors including furfural, vanillin, formic acid, and acetic acid. In a fed-batch fermentation, 74.0g/L of 2,3-BD was obtained from corn stover hydrolysate, with a productivity of 2.1g/Lh and a yield of 94.6%. Thus, this thermophilic B. licheniformis strain is a candidate for the development of efficient industrial production of 2,3-BD from corn stover hydrolysate. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Clean production of corn stover pulp using KOH+NH4OH solution and its kinetic during delignification

    OpenAIRE

    Sun Yong; Yang Gang; Zhang Jin-Ping; Yao Ming-Shun

    2012-01-01

    The self-made KOH together with NH4OH pulping of corn stover was investigated. The combined alkaline system could effectively remove lignin during pulping. There are three stages of lignin removal during delginification. Approximately 90% of lignin could be removed after temperature reached 150ºC for over 30 minutes. The p-hydroxyl phenol groups in lignin could be completely removed during the delignification reaction. The tendency of the increase of the crystalline degree of cellulose ...

  10. INFLUENCE OF BIOPRETREATMENT ON THE CHARACTER OF CORN STOVER LIGNIN AS SHOWN BY THERMOGRAVIMETRIC AND CHEMICAL STRUCTURAL ANALYSES

    OpenAIRE

    Xuewei Yang; Yelin Zeng; Xiaoyu Zhang

    2010-01-01

    The effect of corn stover lignin structure alteration caused by white-rot fungi pretreatment on the pyrolysis kinetics was studied by FTIR and TG/DTA. Results showed that biopretreatment had a remarkable effect on lignin pyrolysis. Biopretreatment can decrease the activation energy and increase the pre-exponential factor in the initial stage of pyrolysis, which makes it possible to start the lignin pyrolysis at a relatively gentle condition and improve the availability of biomass pyrolysis as...

  11. Enhanced Enzymatic Hydrolysis and Structural Features of Corn Stover by NaOH and Ozone Combined Pretreatment

    Directory of Open Access Journals (Sweden)

    Wenhui Wang

    2018-05-01

    Full Text Available A two-step pretreatment using NaOH and ozone was performed to improve the enzymatic hydrolysis, compositions and structural characteristics of corn stover. Comparison between the unpretreated and pretreated corn stover was also made to illustrate the mechanism of the combined pretreatment. A pretreatment with 2% (w/w NaOH at 80 °C for 2 h followed by ozone treatment for 25 min with an initial pH 9 was found to be the optimal procedure and the maximum efficiency (91.73% of cellulose enzymatic hydrolysis was achieved. Furthermore, microscopic observation of changes in the surface structure of the samples showed that holes were formed and lignin and hemicellulose were partially dissolved and removed. X-ray Diffraction (XRD, Fourier Transform Infrared Spectroscopy (FTIR and Cross-Polarization Magic Angle Spinning Carbon-13 Nuclear Magnetic Resonance (CP/MAS 13C-NMR were also used to characterize the chemical structural changes after the combined pretreatment. The results were as follows: part of the cellulose I structure was destroyed and then reformed into cellulose III, the cellulose crystal indices were also changed; a wider space between the crystal layer was observed; disruption of hydrogen bonds in cellulose and disruption of ester bonds in hemicellulose; cleavage of bonds linkage in lignin-carbohydrate complexes; removal of methoxy in lignin and hemicellulose. As a result, all these changes effectively reduced recalcitrance of corn stover and promoted subsequent enzymatic hydrolysis of cellulose.

  12. Effect of acid, steam explosion, and size reduction pretreatments on bio-oil production from sweetgum, switchgrass, and corn stover.

    Science.gov (United States)

    Wang, Hui; Srinivasan, Radhakrishnan; Yu, Fei; Steele, Philip; Li, Qi; Mitchell, Brian; Samala, Aditya

    2012-05-01

    Bio-oil produced from biomass by fast pyrolysis has the potential to be a valuable substitute for fossil fuels. In a recent work on pinewood, we found that pretreatment alters the structure and chemical composition of biomass, which influence fast pyrolysis. In this study, we evaluated dilute acid, steam explosion, and size reduction pretreatments on sweetgum, switchgrass, and corn stover feedstocks. Bio-oils were produced from untreated and pretreated feedstocks in an auger reactor at 450 °C. The bio-oil's physical properties of pH, water content, acid value, density, and viscosity were measured. The chemical characteristics of the bio-oils were determined by gas chromatography-mass spectrometry. The results showed that bio-oil yield and composition were influenced by the pretreatment method and feedstock type. Bio-oil yields of 52, 33, and 35 wt% were obtained from medium-sized (0.68-1.532 mm) untreated sweetgum, switchgrass, and corn stover, respectively, which were higher than the yields from other sizes. Bio-oil yields of 56, 46, and 51 wt% were obtained from 1% H(2)SO(4)-treated medium-sized sweetgum, switchgrass, and corn stover, respectively, which were higher than the yields from untreated and steam explosion treatments.

  13. Alkaline peroxide pretreatment of corn stover: effects of biomass, peroxide, and enzyme loading and composition on yields of glucose and xylose

    Science.gov (United States)

    2011-01-01

    Background Pretreatment is a critical step in the conversion of lignocellulose to fermentable sugars. Although many pretreatment processes are currently under investigation, none of them are entirely satisfactory in regard to effectiveness, cost, or environmental impact. The use of hydrogen peroxide at pH 11.5 (alkaline hydrogen peroxide (AHP)) was shown by Gould and coworkers to be an effective pretreatment of grass stovers and other plant materials in the context of animal nutrition and ethanol production. Our earlier experiments indicated that AHP performed well when compared against two other alkaline pretreatments. Here, we explored several key parameters to test the potential of AHP for further improvement relevant to lignocellulosic ethanol production. Results The effects of biomass loading, hydrogen peroxide loading, residence time, and pH control were tested in combination with subsequent digestion with a commercial enzyme preparation, optimized mixtures of four commercial enzymes, or optimized synthetic mixtures of pure enzymes. AHP pretreatment was performed at room temperature (23°C) and atmospheric pressure, and after AHP pretreatment the biomass was neutralized with HCl but not washed before enzyme digestion. Standard enzyme digestion conditions were 0.2% glucan loading, 15 mg protein/g glucan, and 48 h digestion at 50°C. Higher pretreatment biomass loadings (10% to 20%) gave higher monomeric glucose (Glc) and xylose (Xyl) yields than the 2% loading used in earlier studies. An H2O2 loading of 0.25 g/g biomass was almost as effective as 0.5 g/g, but 0.125 g/g was significantly less effective. Optimized mixtures of four commercial enzymes substantially increased post-AHP-pretreatment enzymatic hydrolysis yields at all H2O2 concentrations compared to any single commercial enzyme. At a pretreatment biomass loading of 10% and an H2O2 loading of 0.5 g/g biomass, an optimized commercial mixture at total protein loadings of 8 or 15 mg/g glucan gave

  14. Alkaline peroxide pretreatment of corn stover: effects of biomass, peroxide, and enzyme loading and composition on yields of glucose and xylose

    Directory of Open Access Journals (Sweden)

    Hodge David B

    2011-06-01

    Full Text Available Abstract Background Pretreatment is a critical step in the conversion of lignocellulose to fermentable sugars. Although many pretreatment processes are currently under investigation, none of them are entirely satisfactory in regard to effectiveness, cost, or environmental impact. The use of hydrogen peroxide at pH 11.5 (alkaline hydrogen peroxide (AHP was shown by Gould and coworkers to be an effective pretreatment of grass stovers and other plant materials in the context of animal nutrition and ethanol production. Our earlier experiments indicated that AHP performed well when compared against two other alkaline pretreatments. Here, we explored several key parameters to test the potential of AHP for further improvement relevant to lignocellulosic ethanol production. Results The effects of biomass loading, hydrogen peroxide loading, residence time, and pH control were tested in combination with subsequent digestion with a commercial enzyme preparation, optimized mixtures of four commercial enzymes, or optimized synthetic mixtures of pure enzymes. AHP pretreatment was performed at room temperature (23°C and atmospheric pressure, and after AHP pretreatment the biomass was neutralized with HCl but not washed before enzyme digestion. Standard enzyme digestion conditions were 0.2% glucan loading, 15 mg protein/g glucan, and 48 h digestion at 50°C. Higher pretreatment biomass loadings (10% to 20% gave higher monomeric glucose (Glc and xylose (Xyl yields than the 2% loading used in earlier studies. An H2O2 loading of 0.25 g/g biomass was almost as effective as 0.5 g/g, but 0.125 g/g was significantly less effective. Optimized mixtures of four commercial enzymes substantially increased post-AHP-pretreatment enzymatic hydrolysis yields at all H2O2 concentrations compared to any single commercial enzyme. At a pretreatment biomass loading of 10% and an H2O2 loading of 0.5 g/g biomass, an optimized commercial mixture at total protein loadings of 8 or 15 mg

  15. Fractionation for further conversion: from raw corn stover to lactic acid

    Science.gov (United States)

    He, Ting; Jiang, Zhicheng; Wu, Ping; Yi, Jian; Li, Jianmei; Hu, Changwei

    2016-12-01

    Fractionation is considered to be one promising strategy to utilize raw biomass to its fullest and produce chemicals with high selectivity. Herein, ethanol/H2O (1/1, v/v) co-solvent with 0.050 M oxalic acid is used to simultaneously fractionate 88.0 wt% of hemicellulose and 89.2 wt% of lignin in corn stover, while cellulose is not obviously degraded. H2O dissolves hemicellulose, G unit and those with β-O-4 linkage of lignin; whereas ethanol extracts G and S units as well as the skeleton with β-5 and β-β linkages of lignin. Oxalic acid effectively catalyzes the hydrolysis of hemicellulose and breaks the intermolecular linkages between hemicellulose and lignin, therefore further promotes the release of lignin. The dissolved hemicelluloses derivatives are reprocessed to produce lactic acid obtaining a high yield of 79.6 wt% with 90% selectivity by the catalysis of MgO. The remained cellulose and recovered lignin can be used further as feedstock to produce chemicals.

  16. Lactic Acid Production from Pretreated Hydrolysates of Corn Stover by a Newly Developed Bacillus coagulans Strain

    Science.gov (United States)

    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-catalyzed sulfite hydrolysate (CASH) as substrates, the concentration of lactic acid reached 45.39, 16.83, and 18.71 g/L by B. coagulans GKN316, respectively. But for B. coagulans NL01, only CASEH could be directly fermented to produce 15.47 g/L lactic acid. The individual inhibitory effect of furfural, 5-hydroxymethylfurfural (HMF), vanillin, syringaldehyde and p-hydroxybenzaldehyde (pHBal) on xylose utilization by B. coagulans GKN316 was also studied. The strain B. coagulans GKN316 could effectively convert these toxic inhibitors to the less toxic corresponding alcohols in situ. These results suggested that B. coagulans GKN316 was well suited to production of lactic acid from undetoxified lignocellulosic hydrolysates. PMID:26863012

  17. 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.

  18. The preparation and ethanol fermentation of high-concentration sugars from steam-explosion corn stover.

    Science.gov (United States)

    Xie, Hui; Wang, Fengqin; Yin, Shuangyao; Ren, Tianbao; Song, Andong

    2015-05-01

    In the field of biofuel ethanol, high-concentration- reducing sugars made from cellulosic materials lay the foundation for high-concentration ethanol fermentation. In this study, corn stover was pre-treated in a process combining chemical methods and steam explosion; the cellulosic hydrolyzed sugars obtained by fed-batch saccharification were then used as the carbon source for high-concentration ethanol fermentation. Saccharomyces cerevisiae 1308, Angel yeast, and Issatchenkia orientalis were shake-cultured with Pachysolen tannophilus P-01 for fermentation. Results implied that the ethanol yields from the three types of mixed strains were 4.85 g/100 mL, 4.57 g/100 mL, and 5.02 g/100 mL (separately) at yield rates of 91.6, 89.3, and 92.2%, respectively. Therefore, it was inferred that shock-fermentation using mixed strains achieved a higher ethanol yield at a greater rate in a shorter fermentation period. This study provided a theoretical basis and technical guidance for the fermentation of industrial high-concentrated cellulosic ethanol.

  19. 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.

  20. Blending municipal solid waste with corn stover for sugar production using ionic liquid process

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Ning [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Xu, Feng [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Sathitsuksanoh, Noppadon [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Thompson, Vicki S. [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Cafferty, Kara [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Li, Chenlin [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Tanjore, Deepti [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Narani, Akash [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Pray, Todd R. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Simmons, Blake A. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Singh, Seema [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Sandia National Laboratories (SNL-CA), Livermore, CA (United States)

    2015-06-01

    Municipal solid waste (MSW) represents an attractive cellulosic resource for sustainable fuel production because of its abundance and its low or perhaps negative cost. However, the significant heterogeneity and toxic contaminants are barriers to efficient conversion to ethanol and other products. In this study, we generated MSW paper mix, blended with corn stover (CS), and have shown that both MSW paper mix alone and MSW/CS blends can be efficiently pretreated in certain ionic liquids (ILs) with high yields of fermentable sugars. After pretreatment in 1-ethyl-3-methylimidazolium acetate ([C2C1Im][OAc]), over 80% glucose has been released with enzymatic saccharification. We have also applied an enzyme free process by adding mineral acid and water directly into the IL/biomass slurry to induce hydrolysis. With the acidolysis process in the IL 1-ethyl-3-methylimidazolium chloride ([C2C1Im]Cl), up to 80% glucose and 90% xylose are released for MSW. The results indicate the feasibility of incorporating MSW as a robust blending agent for biorefineries.

  1. Drought effects on composition and yield for corn stover, mixed grasses, and Miscanthus as bioenergy feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Rachel Emerson; Amber Hoover; Allison Ray; Jeffrey Lacey; Marnie Cortez; Courtney Payne; Doug Karlen; Stuart Birrell; David Laird; Robert Kallenbach; Josh Egenolf; Matthew Sousek; Thomas Voigt

    2014-11-01

    Drought conditions in 2012 were some of the most severe reported in the United States. It is necessary to explore the effects of drought on the quality attributes of current and potential bioenergy feedstocks. Compositional analysis data for corn stover, Miscanthus, and CRP grasses from one or more locations for years 2010 (normal precipitation levels) and 2012 (a known severe drought year nationally) was collected. Results & discussion: The general trend for samples that experienced drought was an increase in extractives and a decrease in structural sugars and lignin. The TEY yields were calculated to determine the drought effects on ethanol production. All three feedstocks had a decrease of 12-14% in TEY when only decreases of carbohydrate content was analyzed. When looking at the compounded effect of both carbohydrate content and the decreases in dry matter loss for each feedstock there was a TEY decrease of 25%-59%. Conclusion: Drought had a significant impact on the quality of all three bioenergy crops. In all cases where drought was experienced both the quality of the feedstock and the yield decreased. These drought induced effects could have significant economic impacts on biorefineries.

  2. 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.

  3. 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.

  4. 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.

  5. Lactic Acid Production from Pretreated Hydrolysates of Corn Stover by a Newly Developed Bacillus coagulans Strain.

    Science.gov (United States)

    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-catalyzed sulfite hydrolysate (CASH) as substrates, the concentration of lactic acid reached 45.39, 16.83, and 18.71 g/L by B. coagulans GKN316, respectively. But for B. coagulans NL01, only CASEH could be directly fermented to produce 15.47 g/L lactic acid. The individual inhibitory effect of furfural, 5-hydroxymethylfurfural (HMF), vanillin, syringaldehyde and p-hydroxybenzaldehyde (pHBal) on xylose utilization by B. coagulans GKN316 was also studied. The strain B. coagulans GKN316 could effectively convert these toxic inhibitors to the less toxic corresponding alcohols in situ. These results suggested that B. coagulans GKN316 was well suited to production of lactic acid from undetoxified lignocellulosic hydrolysates.

  6. Lactic Acid Production from Pretreated Hydrolysates of Corn Stover by a Newly Developed Bacillus coagulans Strain.

    Directory of Open Access Journals (Sweden)

    Ting Jiang

    Full Text Available 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-catalyzed sulfite hydrolysate (CASH as substrates, the concentration of lactic acid reached 45.39, 16.83, and 18.71 g/L by B. coagulans GKN316, respectively. But for B. coagulans NL01, only CASEH could be directly fermented to produce 15.47 g/L lactic acid. The individual inhibitory effect of furfural, 5-hydroxymethylfurfural (HMF, vanillin, syringaldehyde and p-hydroxybenzaldehyde (pHBal on xylose utilization by B. coagulans GKN316 was also studied. The strain B. coagulans GKN316 could effectively convert these toxic inhibitors to the less toxic corresponding alcohols in situ. These results suggested that B. coagulans GKN316 was well suited to production of lactic acid from undetoxified lignocellulosic hydrolysates.

  7. Physical and Chemical Properties of Bio-Oils From Microwave Pyrolysis of Corn Stover

    Science.gov (United States)

    Yu, Fei; Deng, Shaobo; Chen, Paul; Liu, Yuhuan; Wan, Yiqin; Olson, Andrew; Kittelson, David; Ruan, Roger

    This study was aimed to understand the physical and chemical properties of pyrolytic bio-oils produced from microwave pyrolysis of corn stover regarding their potential use as gas turbine and home heating fuels. The ash content, solids content, pH, heating value, minerals, elemental ratio, moisture content, and viscosity of the bio-oils were determined. The water content was approx 15.2 wt%, solids content 0.22 wt%, alkali metal content 12 parts per million, dynamic viscosity 185 mPa·s at 40°C, and gross high heating value 17.5 MJ/kg for a typical bio-oil produced. Our aging tests showed that the viscosity and water content increased and phase separation occurred during the storage at different temperatures. Adding methanol and/or ethanol to the bio-oils reduced the viscosity and slowed down the increase in viscosity and water content during the storage. Blending of methanol or ethanol with the bio-oils may be a simple and cost-effective approach to making the pyrolytic bio-oils into a stable gas turbine or home heating fuels.

  8. Thermogravimetric study and kinetic analysis of fungal pretreated corn stover using the distributed activation energy model.

    Science.gov (United States)

    Ma, Fuying; Zeng, Yelin; Wang, Jinjin; Yang, Yang; Yang, Xuewei; Zhang, Xiaoyu

    2013-01-01

    Non-isothermal thermogravimetry/derivative thermogravimetry (TG/DTG) measurements are used to determine pyrolytic characteristics and kinetics of lignocellulose. TG/DTG experiments at different heating rates with corn stover pretreated with monocultures of Irpex lacteus CD2 and Auricularia polytricha AP and their cocultures were conducted. Heating rates had little effect on the pyrolysis process, but the peak of weight loss rate in the DTG curves shifted towards higher temperature with heating rate. The maximum weight loss of biopretreated samples was 1.25-fold higher than that of the control at the three heating rates, and the maximum weight loss rate of the co-culture pretreated samples was intermediate between that of the two mono-cultures. The activation energies of the co-culture pretreated samples were 16-72 kJ mol(-1) lower than that of the mono-culture at the conversion rate range from 10% to 60%. This suggests that co-culture pretreatment can decrease activation energy and accelerate pyrolysis reaction thus reducing energy consumption. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Fractionation for further conversion: from raw corn stover to lactic acid

    Science.gov (United States)

    He, Ting; Jiang, Zhicheng; Wu, Ping; Yi, Jian; Li, Jianmei; Hu, Changwei

    2016-01-01

    Fractionation is considered to be one promising strategy to utilize raw biomass to its fullest and produce chemicals with high selectivity. Herein, ethanol/H2O (1/1, v/v) co-solvent with 0.050 M oxalic acid is used to simultaneously fractionate 88.0 wt% of hemicellulose and 89.2 wt% of lignin in corn stover, while cellulose is not obviously degraded. H2O dissolves hemicellulose, G unit and those with β-O-4 linkage of lignin; whereas ethanol extracts G and S units as well as the skeleton with β-5 and β-β linkages of lignin. Oxalic acid effectively catalyzes the hydrolysis of hemicellulose and breaks the intermolecular linkages between hemicellulose and lignin, therefore further promotes the release of lignin. The dissolved hemicelluloses derivatives are reprocessed to produce lactic acid obtaining a high yield of 79.6 wt% with 90% selectivity by the catalysis of MgO. The remained cellulose and recovered lignin can be used further as feedstock to produce chemicals. PMID:27917955

  10. Potential of Black Liquor of Potassium Hydroxide to Pretreat Corn Stover for Biomethane Production

    Directory of Open Access Journals (Sweden)

    Muhammad Abdul Hanan Siddhu

    2016-04-01

    Full Text Available Reducing the pretreatment cost of lignocellulosic biomass by utilizing alkali to alter its recalcitrant nature is an effective method for biofuel production. In this experiment, 1.5% KOH solution and its black liquor (spent liquor of KOH (BL were applied to pretreat corn stover (CS at a temperature of 20 °C to enhance the digestibility for anaerobic digestion (AD. Results showed no significant difference in weighted average methane content on the basis of experimental methane and biogas yields between BL-treated and original KOH-treated CS after AD. The BL process significantly increased the overall methane yield by 52.4% compared with untreated CS (135.2 mL/gVS, whereas no significant difference between the overall methane yields of 1.5% KOH-treated and BL-treated CS was observed. In addition, the BL process significantly saved water and KOH consumption, by 56.2% and 57.4%, respectively, compared with the 1.5% KOH pretreatment. Overall methane production was well explained by the modified Gompertz model. The physiochemical changes to CS after BL pretreatment were confirmed by SEM, FTIR, and XRD analyses. Our findings collectively suggest that recycling and reuse of KOH black liquor might be an efficient method for lignocellulosic biomass treatment and have the capability to reduce input costs in future AD processes.

  11. Simultaneous saccharification and ethanol fermentation at high corn stover solids loading in a helical stirring bioreactor.

    Science.gov (United States)

    Zhang, Jian; Chu, Deqiang; Huang, Juan; Yu, Zhanchun; Dai, Gance; Bao, Jie

    2010-03-01

    The higher ethanol titer inevitably requires higher solids loading during the simultaneous enzymatic saccharification and fermentation (SSF) using lignocellulose as the feedstock. The mixing between the solid lignocellulose and the liquid enzyme is crucially important. In this study, a bioreactor with a novel helical impeller was designed and applied to the SSF operation of the steam explosion pretreated corn stover under different solids loadings and different enzyme dosages. The performances using the helical impeller and the common Rushton impeller were compared and analyzed by measuring rheological properties and the mixing energy consumption. The results showed that the new designed stirring system had better performances in the saccharification yield, ethanol titer, and energy cost than those of the Rushton impeller stirring. The mixing energy consumption under different solids loadings and enzyme dosages during SSF operation were analyzed and compared to the thermal energy in the ethanol produced. A balance for achieving the optimal energy cost between the increased mixing energy cost and the reduced distillation energy cost at the high solids loading should be made. The potentials of the new bioreactor were tested under various SSF conditions for obtaining optimal ethanol yield and titer. (c) 2009 Wiley Periodicals, Inc.

  12. Treatment of different parts of corn stover for high yield and lower polydispersity lignin extraction with high-boiling alkaline solvent.

    Science.gov (United States)

    Yang, Mengyao; Rehman, Muhammad Saif Ur; Yan, Tingxuan; Khan, Asad Ullah; Oleskowicz-Popiel, Piotr; Xu, Xia; Cui, Ping; Xu, Jian

    2018-02-01

    The influence of different parts of corn stover on lignin extraction was investigated. Five kinds of lignin were isolated by the high boiling point solvent extraction from the whole corn stover and four different parts including leaf, husk, bark and pith. The optimal condition was obtained: 6.25 g/L NaOH, 140 °C, 1 h and 60% (v/v) 1,4-butanediol. The extracted lignins were then characterized. FT-IR analysis revealed that all of the lignins were typically herbaceous. The lignin extracted from husk contained more S unit. Gel permeation chromatography analysis showed that it was necessary to separate corn stover into different parts to obtain low polydispersity lignin. The SEM and FT-IR analysis proved that the lignin dissolution was related to the tightness structure presenting a positive correlation with hydrogen bond index. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Identification and Antimicrobial Activity Detection of Lactic Acid Bacteria Isolated from Corn Stover Silage

    Directory of Open Access Journals (Sweden)

    Dongxia Li

    2015-05-01

    Full Text Available A total of 59 lactic acid bacteria (LAB strains were isolated from corn stover silage. According to phenotypic and chemotaxonomic characteristics, 16S ribosomal DNA (rDNA sequences and recA gene polymerase chain reaction amplification, these LAB isolates were identified as five species: Lactobacillus (L. plantarum subsp. plantarum, Pediococcus pentosaceus, Enterococcus mundtii, Weissella cibaria and Leuconostoc pseudomesenteroides, respectively. Those strains were also screened for antimicrobial activity using a dual-culture agar plate assay. Based on excluding the effects of organic acids and hydrogen peroxide, two L. plantarum subsp. plantarum strains ZZU 203 and 204, which strongly inhibited Salmonella enterica ATCC 43971T, Micrococcus luteus ATCC 4698T and Escherichia coli ATCC 11775T were selected for further research on sensitivity of the antimicrobial substance to heat, pH and protease. Cell-free culture supernatants of the two strains exhibited strong heat stability (60 min at 100°C, but the antimicrobial activity was eliminated after treatment at 121°C for 15 min. The antimicrobial substance remained active under acidic condition (pH 2.0 to 6.0, but became inactive under neutral and alkaline condition (pH 7.0 to 9.0. In addition, the antimicrobial activities of these two strains decreased remarkably after digestion by protease K. These results preliminarily suggest that the desirable antimicrobial activity of strains ZZU 203 and 204 is the result of the production of a bacteriocin-like substance, and these two strains with antimicrobial activity could be used as silage additives to inhibit proliferation of unwanted microorganism during ensiling and preserve nutrients of silage. The nature of the antimicrobial substances is being investigated in our laboratory.

  14. 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

  15. Ethanol production from hydrothermal pretreated corn stover with a loop reactor

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jian; Thomsen, Mette Hedegaard; Thomsen, Anne Belinda [National Lab for Sustainable Energy, Biosystems Department, Risoe-DTU, P.O. Box 49, DK-4000 Roskilde (Denmark)

    2010-03-15

    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. The pretreatment condition showed a significant impact on xylan recovery. As the pretreatment time prolonged from 10 min to 30 min, the xylan recovery from liquid phase changed between 39.5% and 45.6% and the total xylan recoveries decreased from 84.7% to 61.6%. While the glucan recovery seemed not sensitive to the different pretreatment times. The glucan recovered from liquid was from 4.9% to 5.6% and the total glucan recoveries from all the pretreatments were higher than 98%. Besides HMF and furfural, acetic, lactic, formic and glycolic acids were also found in the liquid phase. All the concentrations of these potential inhibitors were lower enough not to affect the activity of the Saccharomyces cerevisiae (S. cerevisiae). Compared with the ethanol production of 32.4% from the RCS with S. cerevisiae, all the WISs gave higher ethanol productions ranging between 61.2% and 71.2%. When the xylan was taken into consideration, the best pretreatment condition would be 195 C, 15 min and the estimated total ethanol production was 201 g kg{sup -1} RCS by assuming the fermentation of both C-6 and C-5 with the ethanol yield of 0.51 g g{sup -1} and 0.47 g g{sup -1}, respectively. (author)

  16. 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

  17. Influence of Airflow on Laboratory Storage of High Moisture Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Lynn M. Wendt; Ian J. Bonner; Amber N. Hoover; Rachel M. Emerson; William A. Smith

    2014-04-01

    Storing high moisture biomass for bioenergy use is a reality in many areas of the country where wet harvest conditions and environmental factors prevent dry storage from being feasible. Aerobic storage of high moisture biomass leads to microbial degradation and self-heating, but oxygen limitation can aid in material preservation. To understand the influence of oxygen presence on high moisture biomass (50 %, wet basis), three airflow rates were tested on corn stover stored in laboratory reactors. Temperature, carbon dioxide production, dry matter loss, chemical composition, fungal abundance, pH, and organic acids were used to monitor the effects of airflow on storage conditions. The results of this work indicate that oxygen availability impacts both the duration of self-heating and the severity of dry matter loss. High airflow systems experienced the greatest initial rates of loss but a shortened microbially active period that limited total dry matter loss (19 %). Intermediate airflow had improved preservation in short-term storage compared to high airflow systems but accumulated the greatest dry matter loss over time (up to 27 %) as a result of an extended microbially active period. Low airflow systems displayed the best performance with the lowest rates of loss and total loss (10 %) in storage at 50 days. Total structural sugar levels of the stored material were preserved, although glucan enrichment and xylan loss were documented in the high and intermediate flow conditions. By understanding the role of oxygen availability on biomass storage performance, the requirements for high moisture storage solutions may begin to be experimentally defined.

  18. Ammonia, Total Reduced Sulfides, and Greenhouse Gases of Pine Chip and Corn Stover Bedding Packs.

    Science.gov (United States)

    Spiehs, Mindy J; Brown-Brandl, Tami M; Parker, David B; Miller, Daniel N; Berry, Elaine D; Wells, James E

    2016-03-01

    Bedding materials may affect air quality in livestock facilities. Our objective in this study was to compare headspace concentrations of ammonia (NH), total reduced sulfides (TRS), carbon dioxide (CO), methane (CH), and nitrous oxide (NO) when pine wood chips ( spp.) and corn stover ( L.) were mixed in various ratios (0, 10, 20, 30, 40, 60, 80, and 100% pine chips) and used as bedding with manure. Air samples were collected from the headspace of laboratory-scaled bedded manure packs weekly for 42 d. Ammonia concentrations were highest for bedded packs containing 0, 10, and 20% pine chips (equivalent to 501.7, 502.3, and 502.3 mg m, respectively) in the bedding mixture and were lowest when at least 80% pine chips were used as bedding (447.3 and 431.0 mg m, respectively for 80 and 100% pine chip bedding). The highest NH concentrations were observed at Day 28. The highest concentration of TRS was observed when 100% pine chips were used as bedding (11.4 µg m), with high concentrations occurring between Days 7 and 14, and again at Day 35. Greenhouse gases were largely unaffected by bedding material but CH and CO concentrations increased as the bedded packs aged and NO concentrations were highly variable throughout the incubation. We conclude that a mixture of bedding material that contains 30 to 40% pine chips may be the ideal combination to reduce both NH and TRS emissions. All gas concentrations increased as the bedded packs aged, suggesting that frequent cleaning of facilities would improve air quality in the barn, regardless of bedding materials used. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  19. Ethanol production from hydrothermal pretreated corn stover with a loop reactor

    International Nuclear Information System (INIS)

    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 o 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. The pretreatment condition showed a significant impact on xylan recovery. As the pretreatment time prolonged from 10 min to 30 min, the xylan recovery from liquid phase changed between 39.5% and 45.6% and the total xylan recoveries decreased from 84.7% to 61.6%. While the glucan recovery seemed not sensitive to the different pretreatment times. The glucan recovered from liquid was from 4.9% to 5.6% and the total glucan recoveries from all the pretreatments were higher than 98%. Besides HMF and furfural, acetic, lactic, formic and glycolic acids were also found in the liquid phase. All the concentrations of these potential inhibitors were lower enough not to affect the activity of the Saccharomyces cerevisiae (S. cerevisiae). Compared with the ethanol production of 32.4% from the RCS with S. cerevisiae, all the WISs gave higher ethanol productions ranging between 61.2% and 71.2%. When the xylan was taken into consideration, the best pretreatment condition would be 195 o C, 15 min and the estimated total ethanol production was 201 g kg -1 RCS by assuming the fermentation of both C-6 and C-5 with the ethanol yield of 0.51 g g -1 and 0.47 g g -1 , respectively.

  20. 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.

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

    Directory of Open Access Journals (Sweden)

    Bondesson Pia-Maria

    2013-01-01

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

  2. 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

  3. 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

  4. 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

    stover content. Based on the selected datasets, statistical description is provided for all parameters, including mode, median, average and deviation, within each technological configuration. Bivariate correlation analysis across and within all technological configurations indicates that some operational...

  5. Incorporating Agricultural Management Practices into the Assessment of Soil Carbon Change and Life-Cycle Greenhouse Gas Emissions of Corn Stover Ethanol Production

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Zhangcai [Argonne National Lab. (ANL), Argonne, IL (United States); Canter, Christina E. [Argonne National Lab. (ANL), Argonne, IL (United States); Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States); Mueller, Steffen [Univ. of Illinois, Chicago, IL (United States); Kwon, Ho-young [International Food Policy Research Inst., Washington, DC (United States); Han, Jeongwoo [Argonne National Lab. (ANL), Argonne, IL (United States); Wander, Michelle M. [Univ. of Illinois, Champaign, IL (United States); Wang, Michael [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-09-01

    Land management practices such as cover crop adoption or manure application that can increase soil organic carbon (SOC) may provide a way to counter SOC loss upon removal of stover from corn fields for use as a biofuel feedstock. This report documents the data, methodology, and assumptions behind the incorporation of land management practices into corn-soybean systems that dominate U.S. grain production using varying levels of stover removal in the GREETTM (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) model and its CCLUB (Carbon Calculator for Land Use change from Biofuels production) module. Tillage (i.e., conventional, reduced and no tillage), corn stover removal (i.e., at 0, 30% and 60% removal rate), and organic matter input techniques (i.e., cover crop and manure application) are included in the analysis as major land management practices. Soil carbon changes associated with land management changes were modeled with a surrogate CENTURY model. The resulting SOC changes were incorporated into CCLUB while GREET was expanded to include energy and material consumption associated with cover crop adoption and manure application. Life-cycle greenhouse gas (GHG) emissions of stover ethanol were estimated using a marginal approach (all burdens and benefits assigned to corn stover ethanol) and an energy allocation approach (burdens and benefits divided between grain and stover ethanol). In the latter case, we considered corn grain and corn stover ethanol to be produced at an integrated facility. Life-cycle GHG emissions of corn stover ethanol are dependent upon the analysis approach selected (marginal versus allocation) and the land management techniques applied. The expansion of CCLUB and GREET to accommodate land management techniques can produce a wide range of results because users can select from multiple scenario options such as choosing tillage levels, stover removal rates, and whether crop yields increase annually or remain constant

  6. Effect of xylan and lignin removal by batch and flowthrough pretreatment on the enzymatic digestibility of corn stover cellulose.

    Science.gov (United States)

    Yang, Bin; Wyman, Charles E

    2004-04-05

    Compared with batch systems, flowthrough and countercurrent reactors have important potential advantages for pretreating cellulosic biomass, including higher hemicellulose sugar yields, enhanced cellulose digestibility, and reduced chemical additions. Unfortunately, they suffer from high water and energy use. To better understand these trade-offs, comparative data are reported on xylan and lignin removal and enzymatic digestibility of cellulose for corn stover pretreated in batch and flowthrough reactors over a range of flow rates between 160 degrees and 220 degrees C, with water only and also with 0.1 wt% sulfuric acid. Increasing flow with just water enhanced the xylan dissolution rate, more than doubled total lignin removal, and increased cellulose digestibility. Furthermore, adding dilute sulfuric acid increased the rate of xylan removal for both batch and flowthrough systems. Interestingly, adding acid also increased the lignin removal rate with flow, but less lignin was left in solution when acid was added in batch. Although the enzymatic hydrolysis of pretreated cellulose was related to xylan removal, as others have shown, the digestibility was much better for flowthrough compared with batch systems, for the same degree of xylan removal. Cellulose digestibility for flowthrough reactors was related to lignin removal as well. These results suggest that altering lignin also affects the enzymatic digestibility of corn stover. Copyright 2004 Wiley Periodicals, Inc.

  7. Slagging Behavior of Straw and Corn Stover and the Fate of Potassium under Entrained-Flow Gasification Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Leiser, S.; Cieplik, M.K.; Smit, R. [Energy research Centre of the Netherlands ECN, Post Office Box 1, 1755 ZG Petten (Netherlands)

    2013-07-01

    The behavior of straw and corn stover (non-food agricultural residues potentially available for power generation) was studied in a lab-scale reactor under entrained-flow gasification conditions typical for existing integrated gasification combined cycle power systems. This experimental work was assisted by a range of ash-specific analyses and thermodynamic modeling to gain insights into both the physics and chemistry of ash formation and melting behavior. It was observed that, although the major part of the primarily siliceous native ash promptly forms a molten slag, much of the alkalis are evaporated into the syngas. These gas-borne alkalis can potentially cause aerosol formation in the gasifier, gas quench, syngas cooler, and quench systems, resulting in both operating problems (fouling) and emission issues. To minimize the alkali release from straw and corn stover, the addition of an additive (clay) has been proven to be a highly promising method without the negative effects for the melting behavior of the slag.

  8. 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)

  9. The Role of Product Inhibition as a Yield-Determining Factor in Enzymatic High-Solid Hydrolysis of Pretreated Corn Stover

    DEFF Research Database (Denmark)

    Nymand Olsen, Søren; Borch, Kim; Cruys-Bagger, Nicolaj

    2014-01-01

    . The results suggest that the solid effect is mainly controlled by product inhibition under the given experimental conditions (washed pretreated corn stover as substrate). Cellobiose was found to be approximately 15 times more inhibitory than glucose on a molar scale. However, considering that glucose...

  10. 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. PMID:24763192

  11. High titer L-lactic acid production from corn stover with minimum wastewater generation and techno-economic evaluation based on Aspen plus modeling.

    Science.gov (United States)

    Liu, Gang; Sun, Jiaoe; Zhang, Jian; Tu, Yi; Bao, Jie

    2015-12-01

    Technological potentials of l-lactic acid production from corn stover feedstock were investigated by experimental and techno-economic studies. An optimal performance with 104.5 g/L in l-lactic acid titer and 71.5% in overall yield from cellulose in corn stover to l-lactic acid using an engineered Pediococcus acidilactici strain were obtained by overcoming several technical barriers. A rigorous Aspen plus model for l-lactic acid production starting from dry dilute acid pretreated and biodetoxified corn stover was developed. The techno-economic analysis shows that the minimum l-lactic acid selling price (MLSP) was $0.523 per kg, which was close to that of the commercial l-lactic acid produced from starch feedstock, and 24% less expensive than that of ethanol from corn stover, even though the xylose utilization was not considered. The study provided a prototype of industrial application and an evaluation model for high titer l-lactic acid production from lignocellulose feedstock. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. 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.

  13. Fast microwave-assisted catalytic co-pyrolysis of corn stover and scum for bio-oil production with CaO and HZSM-5 as the catalyst.

    Science.gov (United States)

    Liu, Shiyu; Xie, Qinglong; Zhang, Bo; Cheng, Yanling; Liu, Yuhuan; Chen, Paul; Ruan, Roger

    2016-03-01

    This study investigated fast microwave-assisted catalytic co-pyrolysis of corn stover and scum for bio-oil production with CaO and HZSM-5 as the catalyst. Effects of reaction temperature, CaO/HZSM-5 ratio, and corn stover/scum ratio on co-pyrolysis product fractional yields and selectivity were investigated. Results showed that co-pyrolysis temperature was selected as 550°C, which provides the maximum bio-oil and aromatic yields. Mixed CaO and HZSM-5 catalyst with the weight ratio of 1:4 increased the aromatic yield to 35.77 wt.% of feedstock, which was 17% higher than that with HZSM-5 alone. Scum as the hydrogen donor, had a significant synergistic effect with corn stover to promote the production of bio-oil and aromatic hydrocarbons when the H/C(eff) value exceeded 1. The maximum yield of aromatic hydrocarbons (29.3 wt.%) were obtained when the optimal corn stover to scum ratio was 1:2. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Odorous volatile organic compounds, Escherichia coli, and nutrient concentrations when kiln-dried pine chips and corn stover bedding are used in beef bedded manure packs

    Science.gov (United States)

    Pine (Pinus spp.) bedding has been shown to lower the concentration of odorous volatile organic compounds (VOCs) and pathogenic bacteria compared with corn (Zea mays L.) stover bedding, but availability and cost limit the use of pine bedding in cattle confinement facilities. The objectives of this s...

  15. 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

  16. 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

  17. 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.

  18. 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.

  19. 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.

  20. Heterologous Acidothermus cellulolyticus 1,4-β-Endoglucanase E1 Produced Within the Corn Biomass Converts Corn Stover Into Glucose

    Science.gov (United States)

    Ransom, Callista; Balan, Venkatesh; Biswas, Gadab; Dale, Bruce; Crockett, Elaine; Sticklen, Mariam

    Commercial conversion of lignocellulosic biomass to fermentable sugars requires inexpensive bulk production of biologically active cellulase enzymes, which might be achieved through direct production of these enzymes within the biomass crops. Transgenic corn plants containing the catalytic domain of Acidothermus cellulolyticus E1 endo-1,4-β glucanase and the bar bialaphos resistance coding sequences were generated after Biolistic® (BioRad Hercules, CA) bombardment of immature embryo-derived cells. E1 sequences were regulated under the control of the cauliflower mosaic virus 35S promoter and tobacco mosaic virus translational enhancer, and E1 protein was targeted to the apoplast using the signal peptide of tobacco pathogenesis-related protein to achieve accumulation of this enzyme. The integration, expression, and segregation of E1 and bar transgenes were demonstrated, respectively, through Southern and Western blotting, and progeny analyses. Accumulation of up to 1.13% of transgenic plant total soluble proteins was detected as biologically active E1 by enzymatic activity assay. The corn-produced, heterologous E1 could successfully convert ammonia fiber explosion-pretreated corn stover polysaccharides into glucose as a fermentable sugar for ethanol production, confirming that the E1 enzyme is produced in its active from.

  1. A novel film-pore-surface diffusion model to explain the enhanced enzyme adsorption of corn stover pretreated by ultrafine grinding.

    Science.gov (United States)

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

    2016-01-01

    Ultrafine grinding is an environmentally friendly pretreatment that can alter the degree of polymerization, the porosity and the specific surface area of lignocellulosic biomass and can, thus, enhance cellulose hydrolysis. Enzyme adsorption onto the substrate is a prerequisite for the enzymatic hydrolysis process. Therefore, it is necessary to investigate the enzyme adsorption properties of corn stover pretreated by ultrafine grinding. The ultrafine grinding pretreatment was executed on corn stover. The results showed that ultrafine grinding pretreatment can significantly decrease particle size [from 218.50 μm of sieve-based grinding corn stover (SGCS) to 17.45 μm of ultrafine grinding corn stover (UGCS)] and increase the specific surface area (SSA), pore volume (PV) and surface composition (SSA: from 1.71 m(2)/g of SGCS to 2.63 m(2)/g of UGCS, PV: from 0.009 cm(3)/g of SGCS to 0.024 m(3)/g of UGCS, cellulose surface area: from 168.69 m(2)/g of SGCS to 290.76 m(2)/g of UGCS, lignin surface area: from 91.46 m(2)/g of SGCS to 106.70 m(2)/g of UGCS). The structure and surface composition changes induced by ultrafine grinding increase the enzyme adsorption capacity from 2.83 mg/g substrate of SGCS to 5.61 mg/g substrate of UGCS. A film-pore-surface diffusion model was developed to simultaneously predict the enzyme adsorption kinetics of both the SGCS and UGCS. Satisfactory predictions could be made with the model based on high R (2) and low RMSE values (R (2) = 0.95 and RMSE = 0.16 mg/g for the UGCS, R (2) = 0.93 and RMSE = 0.09 mg/g for the SGCS). The model was further employed to analyze the rate-limiting steps in the enzyme adsorption process. Although both the external-film and internal-pore mass transfer are important for enzyme adsorption on the SGCS and UGCS, the UGCS has a lower internal-pore resistance compared to the SGCS. Ultrafine grinding pretreatment can enhance the enzyme adsorption onto corn stover by altering structure and

  2. Projection of corn production and stover-harvesting impacts on soil organic carbon dynamics in the U.S. Temperate Prairies

    Science.gov (United States)

    Wu, Yiping; Liu, Shuguang; Young, Claudia J.; Dahal, Devendra; Sohl, Terry L.; Davis, Brian

    2015-01-01

    Terrestrial carbon sequestration potential is widely considered as a realistic option for mitigating greenhouse gas emissions. However, this potential may be threatened by global changes including climate, land use, and management changes such as increased corn stover harvesting for rising production of cellulosic biofuel. Therefore, it is critical to investigate the dynamics of soil organic carbon (SOC) at regional or global scale. This study simulated the corn production and spatiotemporal changes of SOC in the U.S. Temperate Prairies, which covers over one-third of the U.S. corn acreage, using a biogeochemical model with multiple climate and land-use change projections. The corn production (either grain yield or stover biomass) could reach 88.7–104.7 TgC as of 2050, 70–101% increase when compared to the base year of 2010. A removal of 50% stover at the regional scale could be a reasonable cap in view of maintaining SOC content and soil fertility especially in the beginning years. The projected SOC dynamics indicated that the average carbon sequestration potential across the entire region may vary from 12.7 to 19.6 g C/m2/yr (i.e., 6.6–10.2 g TgC/yr). This study not only helps understand SOC dynamics but also provides decision support for sustainable biofuel development.

  3. Corn stover for biogas production: Effect of steam explosion pretreatment on the gas yields and on the biodegradation kinetics of the primary structural compounds.

    Science.gov (United States)

    Lizasoain, Javier; Trulea, Adrian; Gittinger, Johannes; Kral, Iris; Piringer, Gerhard; Schedl, Andreas; Nilsen, Paal J; Potthast, Antje; Gronauer, Andreas; Bauer, Alexander

    2017-11-01

    This study evaluated the effect of steam explosion on the chemical composition and biomethane potential of corn stover using temperatures ranging between 140 and 220°C and pretreatment times ranging between 2 and 15min. Biodegradation kinetics during the anaerobic digestion of untreated and corn stover, pretreated at two different intensities, 140°C for 5min and 180°C for 5min, were studied in tandem. Results showed that pretreatment at 160°C for 2min improved the methane yield by 22%. Harsher pretreatment conditions led to lower hemicellulose contents and methane yields, as well as higher lignin contents, which may be due to the formation of pseudo-lignin. The biodegradation kinetics trial demonstrated that steam explosion enhances the degradation of structural carbohydrates and acid insoluble lignin. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Detoxification of corn stover and corn starch pyrolysis liquors by Pseudomonas putida and Streptomyces setonii suspended cells and plastic compost support biofilms.

    Science.gov (United States)

    Khiyami, Mohammad A; Pometto Iii, Anthony L; Brown, Robert C

    2005-04-20

    Plant biomass can be liquefied into fermentable sugars (levoglucosan then to glucose) for the production of ethanol, lactic acid, enzymes, and more by a process called pyrolysis. During the process microbial inhibitors are also generated. Pseudomonas putida (ATCC 17484) and Streptomyces setonii75Vi2 (ATCC 39116) were employed to degrade microbial inhibitors in diluted corn stover (Dcs) and diluted corn starch (Dst) pyrolysis liquors. The detoxification process evaluation included measuring total phenols and changes in UV spectra, a GC-MS analysis, and a bioassay, which employed Lactobacillus casei subsp. rhamosus (ATCC 11443) growth as an indicator of detoxification. Suspended-cell cultures illustrated limited detoxification ability of Dcs and Dst. P. putida and S. setoniiplastic compost support (PCS) biofilm continuous-stirred-tank-reactor pure cultures detoxified 10 and 25% (v/v) Dcs and Dst, whereas PCS biofilm mixed culture also partially detoxified 50% (v/v) Dcs and Dst in repeated batch culture. Therefore, PCS biofilm mixed culture is the process of choice to detoxify diluted pyrolysis liquors.

  5. Effect of irradiation, as a pretreatment, on bioconversion of corn stover into protein-rich mycelial biomass of Pleurotus sajor-caju

    Energy Technology Data Exchange (ETDEWEB)

    Awafo, V.A.; Chahal, D.S.; Charbonneau, R. [Universite du Quebec (Canada). Applied Microbiology Research Center

    1995-10-01

    Application of irradiation for food preservation, for pretreatment of lignocellulosic materials for their hydrolysis and to increase the digestibility of lignocellulosic materials for rumen animals have been reported in the literature. In the present study, irradiation (100 KGy to 1.7 MGy) of corn stover as a pretreatment to make it susceptible for its bioconversion into protein-rich mycelial biomass of Pleurotus sajor-caju NRRL 18757 has been compared with that of mild alkali treatment (0.01 to 0.15 g NaOH/g corn stover), the most commonly used pretreatment. Protein synthesis increased with the increase in doses of irradiation as well as with the increase in concentration of NaOH. Combination pretreatment with NaOH and {gamma}-irradiation reduced the quantity of NaOH and doses of irradiation required to get optimum yields of protein indicating a strong synergistic effect. The highest protein content of the final product, mycelial biomass, was about 45% on dry weight basis. More than 90% utilization of corn stover polysaccharides for the synthesis of protein-rich mycelial biomass of P. sajor-caju was recorded. (author).

  6. Effect of irradiation, as a pretreatment, on bioconversion of corn stover into protein-rich mycelial biomass of Pleurotus sajor-caju

    International Nuclear Information System (INIS)

    Awafo, V.A.; Chahal, D.S.; Charbonneau, R.

    1995-01-01

    Application of irradiation for food preservation, for pretreatment of lignocellulosic materials for their hydrolysis and to increase the digestibility of lignocellulosic materials for rumen animals have been reported in the literature. In the present study, irradiation (100 KGy to 1.7 MGy) of corn stover as a pretreatment to make it susceptible for its bioconversion into protein-rich mycelial biomass of Pleurotus sajor-caju NRRL 18757 has been compared with that of mild alkali treatment (0.01 to 0.15 g NaOH/g corn stover), the most commonly used pretreatment. Protein synthesis increased with the increase in doses of irradiation as well as with the increase in concentration of NaOH. Combination pretreatment with NaOH and γ-irradiation reduced the quantity of NaOH and doses of irradiation required to get optimum yields of protein indicating a strong synergistic effect. The highest protein content of the final product, mycelial biomass, was about 45% on dry weight basis. More than 90% utilization of corn stover polysaccharides for the synthesis of protein-rich mycelial biomass of P. sajor-caju was recorded. (author)

  7. Effect of irradiation, as a pretreatment, on bioconversion of corn stover into protein-rich mycelial biomass of Pleurotus sajor-caju

    International Nuclear Information System (INIS)

    Awafo, V.A.; Chahal, D.S.; Charbonneau, R.

    1995-01-01

    Application of irradiation for food preservation, for pretreatment of lignocellulosic materials for their hydrolysis and to increase the digestibility of lignocellulosic materials for rumen animals have been reported in the literature. In the present study, irradiation (100 KGy to 1.7 MGy) of corn stover as a pretreatment to make it susceptible for its bioconversion into protein-rich mycelial biomass of Pleurotus sajor-caju NRRL 18757 has been compared with that of mied alkali treatment (0.01 to 0.15 g NaOH/g corn stover), the most commonly used pretreatment. Protein synthesis increased with the increase in doses of irradiation as well as with the increase in concentration of NaOH. Combination pretreatment with NaOH and γ-irradiation reduced the quantity of NaOH and doses of irradiation required to get optimum yields of protein indicating a strong synergistic effect. This highest protein content of the final product, mycelial biomass, was about 45% on dry weight basis. More than 90% utilization of corn stover polysaccharides for the synthesis of protein-rich mycelial biomass of P.sajor-caju was recorded. (author)

  8. Investigation of the Spectroscopic Information on Functional Groups Related to Carbohydrates in Different Morphological Fractions of Corn Stover and Their Relationship to Nutrient Supply and Biodegradation Characteristics.

    Science.gov (United States)

    Xin, Hangshu; Ding, Xue; Zhang, Liyang; Sun, Fang; Wang, Xiaofan; Zhang, Yonggen

    2017-05-24

    The objectives of this study were to investigate (1) nutritive values and biodegradation characteristics and (2) mid-IR spectroscopic features within the regions associated with carbohydrate functional groups (including cellulosic component (CELC), structural carbohydrate (STCHO), and total carbohydrate (CHO)) in different morphological fractions of corn stover. Furthermore, correlation and regression analyses were also applied to determine the relationship between nutritional values and spectroscopic parameters. The results showed that different morphological sections of corn stover had different nutrient supplies, in situ biodegradation characteristics, and spectral structural features within carbohydrate regions. The stem rind and ear husk were both high in fibrous content, which led to the lowest effective degradabilities (ED) among these stalk fractions. The ED values of NDF were ranked ear husk > stem pith > leaf blade > leaf sheath > whole plant > stem rind. Intensities of peak height and area within carbohydrate regions were relatively more stable compared with spectral ratio profiles. Significant difference was found only in peak area intensity of CELC, which was at the highest level for stem rind, followed by stem pith, leaf sheath, whole plant, leaf blade, and ear husk. Correlation results showed that changes in some carbohydrate spectral ratios were highly associated with carbohydrate chemical profiles and in situ rumen degradation kinetics. Among the various carbohydrate molecular spectral parameters that were tested in multiple regression analysis, CHO height ratios, and area ratios of CELC:CHO and CELC:STCHO as well as CELC area were mostly sensitive to nutrient supply and biodegradation characteristics in different morphological fractions of corn stover.

  9. Influence of Pyrolysis Temperature on Physico-Chemical Properties of Corn Stover (Zea mays L. Biochar and Feasibility for Carbon Capture and Energy Balance.

    Directory of Open Access Journals (Sweden)

    Muhammad Khalid Rafiq

    Full Text Available This study examined the influence of pyrolysis temperature on biochar characteristics and evaluated its suitability for carbon capture and energy production. Biochar was produced from corn stover using slow pyrolysis at 300, 400 and 500°C and 2 hrs holding time. The experimental biochars were characterized by elemental analysis, BET, FTIR, TGA/DTA, NMR (C-13. Higher heating value (HHV of feedstock and biochars was measured using bomb calorimeter. Results show that carbon content of corn stover biochar increased from 45.5% to 64.5%, with increasing pyrolysis temperatures. A decrease in H:C and O:C ratios as well as volatile matter, coupled with increase in the concentration of aromatic carbon in the biochar as determined by FTIR and NMR (C-13 demonstrates a higher biochar carbon stability at 500°C. It was estimated that corn stover pyrolysed at 500°C could provide of 10.12 MJ/kg thermal energy. Pyrolysis is therefore a potential technology with its carbon-negative, energy positive and soil amendment benefits thus creating win- win scenario.

  10. Influence of Pyrolysis Temperature on Physico-Chemical Properties of Corn Stover (Zea mays L.) Biochar and Feasibility for Carbon Capture and Energy Balance.

    Science.gov (United States)

    Rafiq, Muhammad Khalid; Bachmann, Robert Thomas; Rafiq, Muhammad Tariq; Shang, Zhanhuan; Joseph, Stephen; Long, Ruijun

    2016-01-01

    This study examined the influence of pyrolysis temperature on biochar characteristics and evaluated its suitability for carbon capture and energy production. Biochar was produced from corn stover using slow pyrolysis at 300, 400 and 500°C and 2 hrs holding time. The experimental biochars were characterized by elemental analysis, BET, FTIR, TGA/DTA, NMR (C-13). Higher heating value (HHV) of feedstock and biochars was measured using bomb calorimeter. Results show that carbon content of corn stover biochar increased from 45.5% to 64.5%, with increasing pyrolysis temperatures. A decrease in H:C and O:C ratios as well as volatile matter, coupled with increase in the concentration of aromatic carbon in the biochar as determined by FTIR and NMR (C-13) demonstrates a higher biochar carbon stability at 500°C. It was estimated that corn stover pyrolysed at 500°C could provide of 10.12 MJ/kg thermal energy. Pyrolysis is therefore a potential technology with its carbon-negative, energy positive and soil amendment benefits thus creating win- win scenario.

  11. The effects on digestibility and ruminal measures of chemically treated corn stover as a partial replacement for grain in dairy diets.

    Science.gov (United States)

    Cook, D E; Combs, D K; Doane, P H; Cecava, M J; Hall, M B

    2016-08-01

    Alkaline treatment of gramineous crop residues can convert an abundant, minimally utilized, poorly digestible straw into a moderately digestible feedstuff. Given the volatile nature of grain prices, substitution of treated stover for grain was investigated with dairy cows to provide insights on ruminal and digestibility effects of a feed option that makes use of alternative, available resources. The objective of this study was to evaluate changes in diet digestibility and ruminal effects when increasing levels of calcium oxide-treated corn stover (CaOSt) were substituted for corn grain in diets of lactating cows. Mature corn stover was treated with calcium oxide at a level of 50g∙kg(-1) dry matter (DM), brought up to a moisture content of 50% following bale grinding, and stored anaerobically at ambient temperatures for greater than 60d before the feeding experiment. Eight ruminally cannulated Holstein cows averaging 686kg of body weight and 35kg of milk∙d(-1) were enrolled in a replicated 4×4 Latin square, where CaOSt replaced corn grain on a DM basis in the ration at rates of 0, 40, 80, and 120g∙kg(-1) DM. All reported significant responses were linear. The DM intake declined by approximately 1kg per 4% increase in CaOSt inclusion. With increasing replacement of corn grain, dietary neutral detergent fiber (NDF) concentration increased. However, rumen NDF turnover, NDF digestibility, NDF passage rate, and digestion rate of potentially digestible NDF were unaffected by increasing CaOSt inclusion. Total-tract organic matter digestibility declined by 5 percentage units over the range of treatments, approximately 1.5 units per 4-percentage-unit substitution of CaOSt for grain. With increasing CaOSt, the molar proportions of butyrate and valerate declined, whereas the lowest detected ruminal pH increased from 5.83 to 5.94. Milk, fat, and protein yields declined as CaOSt increased and DM intake declined with the result that net energy in milk declined by

  12. Effects of calcium oxide treatment at varying moisture concentrations on the chemical composition, in situ degradability, in vitro digestibility and gas production kinetics of anaerobically stored corn stover.

    Science.gov (United States)

    Shi, H T; Cao, Z J; Wang, Y J; Li, S L; Yang, H J; Bi, Y L; Doane, P H

    2016-08-01

    The objective of this study was to determine the optimum conditions for calcium oxide (CaO) treatment of anaerobically stored corn stover by in situ and in vitro methods. Four ruminally cannulated, non-lactating, non-pregnant Holstein cows were used to determine the in situ effective degradabilities of dry matter (ISDMD), organic matter (ISOMD), neutral detergent fibre (ISNDFD), in vitro organic matter disappearance (IVOMD) and gas production in 72 h (GP72h ) of corn stover. A completely randomized design involving a 3 × 3 factorial arrangement was adopted. Ground corn stover was treated with different levels of CaO (3%, 5% and 7% of dry stover) at varying moisture contents (40%, 50% and 60%) and stored under anaerobic conditions for 15 days before analysis. Compared with untreated corn stover, the CaO-treated stover had increased ash and calcium (Ca) contents but decreased aNDF and OM contents. The moisture content, CaO level and their interaction affected (p  0.01) in these in situ degradability parameters were observed between the stover treated with 5% CaO at 60% moisture content and those treated with 7% CaO at 60% moisture content. Corn stover treated with 5% CaO at 50% moisture had the maximum IVOMD and GP72 h among the treatments, and there was no difference (p > 0.01) between 50% and 60% moisture. Results from this study suggested that 5% CaO applied at 60% moisture could be an effective and economical treatment combination. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

  13. Physicochemical properties of bio-oil and biochar produced by fast pyrolysis of stored single-pass corn stover and cobs.

    Science.gov (United States)

    Shah, Ajay; Darr, Matthew J; Dalluge, Dustin; Medic, Dorde; Webster, Keith; Brown, Robert C

    2012-12-01

    Short harvest window of corn (Zea mays) stover necessitates its storage before utilization; however, there is not enough work towards exploring the fast pyrolysis behavior of stored biomass. This study investigated the yields and the physicochemical properties (proximate and ultimate analyses, higher heating values and acidity) of the fast pyrolysis products obtained from single-pass stover and cobs stored either inside a metal building or anaerobically within plastic wraps. Biomass samples were pyrolyzed in a 183 cm long and 2.1cm inner diameter free-fall fast pyrolysis reactor. Yields of bio-oil, biochar and non-condensable gases from different biomass samples were in the ranges of 45-55, 25-37 and 11-17 wt.%, respectively, with the highest bio-oil yield from the ensiled single-pass stover. Bio-oils generated from ensiled single-pass cobs and ensiled single-pass stover were, respectively, the most and the least acidic with the modified acid numbers of 95.0 and 65.2 mg g(-1), respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    Kaparaju, Prasad; Felby, Claus

    2010-05-01

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

  15. Clean production of corn stover pulp using KOH+NH4OH solution and its kinetic during delignification

    Directory of Open Access Journals (Sweden)

    Sun Yong

    2012-01-01

    Full Text Available The self-made KOH together with NH4OH pulping of corn stover was investigated. The combined alkaline system could effectively remove lignin during pulping. There are three stages of lignin removal during delginification. Approximately 90% of lignin could be removed after temperature reached 150ºC for over 30 minutes. The p-hydroxyl phenol groups in lignin could be completely removed during the delignification reaction. The tendency of the increase of the crystalline degree of cellulose is observed with increase of reaction temperature. The kinetics of delignification is found to be the first order with respect to the remained lignin and the 0.4 order with respect to the remained hydroxide concentration. The activation energy of delignification is 23 kJ/mol. The solution obtained from precipitation of lignin is rich in nitrogen, phosphorous, potassium elements and organic matters. Various techniques including FT-IR, GPC, DSC, were applied to characterize the acid precipitated lignin. The result shows that the lignin with the polydispersity of 1.4 still maintains the p-coumaryl, coniferyl, and sinapyl units in its matrix.

  16. Impact of co-pretreatment of calcium hydroxide and steam explosion on anaerobic digestion efficiency with corn stover.

    Science.gov (United States)

    Ji, Jinli; Zhang, Jiyu; Yang, Liutianyi; He, Yanfeng; Zhang, Ruihong; Liu, Guangqing; Chen, Chang

    2017-06-01

    Anaerobic digestion (AD) is an effective way to utilize the abundant resource of corn stover (CS). In this light, Ca(OH) 2 pretreatment alone, steam explosion (SE) pretreatment alone, and co-pretreatment of Ca(OH) 2 and SE were applied to improve the digestion efficiency of CS. Results showed that AD of co-pretreated CS with 1.0% Ca(OH) 2 and SE at 1.5 MPa achieved the highest cumulative methane yield of [Formula: see text], which was 61.54% significantly higher (p < .01) than untreated CS. The biodegradability value of CS after co-pretreatment enhanced from 43.03% to 69.52%. Methane yield could be well fitted by the first-order model and the modified Gompertz model. In addition, composition and structural changes of CS after pretreatment were analyzed by a fiber analyzer, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. The validated results indicated that co-pretreatment of Ca(OH) 2 and SE was efficient to improve the digestion performance of CS and might be a suitable method for agricultural waste pretreatment in the future AD industry.

  17. 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 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.

  18. Serial completely stirred tank reactors for improving biogas production and substance degradation during anaerobic digestion of corn stover.

    Science.gov (United States)

    Li, YuQian; Liu, ChunMei; Wachemo, Akiber Chufo; Yuan, HaiRong; Zou, DeXun; Liu, YanPing; Li, XiuJin

    2017-07-01

    Several completely stirred tank reactors (CSTR) connected in series for anaerobic digestion of corn stover were investigated in laboratory scale. Serial anaerobic digestion systems operated at a total HRT of 40days, and distribution of HRT are 10+30days (HRT10+30d), 20+20days (HRT20+20d), and 30+10days (HRT30+10d) were compared to a conventional one-step CSTR at the same HRT of 40d. The results showed that in HRT10+30d serial system, the process became very unstable at organic load of 50gTS·L -1 . The HRT20+20d and HRT30+10d serial systems improved methane production by 8.3-14.6% compared to the one-step system in all loads of 50, 70, 90gTS·L -1 . The conversion rates of total solid, cellulose, and hemicellulose were increased in serial anaerobic digestion systems compared to single system. The serial systems showed more stable process performance in high organic load. HRT30+10d system showed the best biogas production and conversions among all systems. Copyright © 2017. Published by Elsevier Ltd.

  19. Enhancing methane production of corn stover through a novel way: sequent pretreatment of potassium hydroxide and steam explosion.

    Science.gov (United States)

    Li, Jianghao; Zhang, Ruihong; Siddhu, Muhammad Abdul Hanan; He, Yanfeng; Wang, Wen; Li, Yeqing; Chen, Chang; Liu, Guangqing

    2015-04-01

    Getting over recalcitrance of lignocellulose is effective way to fuel production from lignocellulosic biomass. In current work, different pretreatments were applied to enhance the digestibility of corn stover (CS). Results showed that steam explosion (SE)-treated CS produced maximal methane yield (223.2 mL/gvs) at 1.2 MPa for 10 min, which was 55.2% more than untreated (143.8 mL/gvs). Whereas 1.5% KOH-treated CS produced maximum methane yield of 208.6 mL/gvs, and significantly (αpotassium hydroxide and steam explosion (SPPE) (1.5% KOH-1.2 MPa, 10 min) achieved a very significant (α<0.01) improvement (80.0%) of methane yield (258.8 mL/gvs) compared with untreated CS. Methane production could be well explained by the first-order and modified Gompertz models. Besides, SEM, FTIR, and XRD analyses validated structural changes of CS after SPPE. SPPE might be a promising method to pretreat CS in the future AD industry. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Development of rapid bioconversion with integrated recycle technology for ethanol production from extractive ammonia pretreated corn stover.

    Science.gov (United States)

    Jin, Mingjie; Liu, Yanping; da Costa Sousa, Leonardo; Dale, Bruce E; Balan, Venkatesh

    2017-08-01

    High enzyme loading and low productivity are two major issues impeding low cost ethanol production from lignocellulosic biomass. This work applied rapid bioconversion with integrated recycle technology (RaBIT) and extractive ammonia (EA) pretreatment for conversion of corn stover (CS) to ethanol at high solids loading. Enzymes were recycled via recycling unhydrolyzed solids. Enzymatic hydrolysis with recycled enzymes and fermentation with recycled yeast cells were studied. Both enzymatic hydrolysis time and fermentation time were shortened to 24 h. Ethanol productivity was enhanced by two times and enzyme loading was reduced by 30%. Glucan and xylan conversions reached as high as 98% with an enzyme loading of as low as 8.4 mg protein per g glucan. The overall ethanol yield was 227 g ethanol/kg EA-CS (191 g ethanol/kg untreated CS). Biotechnol. Bioeng. 2017;114: 1713-1720. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  1. Catalytic performance of corn stover hydrolysis by a new isolate Penicillium sp. ECU0913 producing both cellulase and xylanase.

    Science.gov (United States)

    Shi, Qian-Qian; Sun, Jie; Yu, Hui-Lei; Li, Chun-Xiu; Bao, Jie; Xu, Jian-He

    2011-07-01

    A fungal strain, marked as ECU0913, producing high activities of both cellulase and xylanase was newly isolated from soil sample collected near decaying straw and identified as Penicillium sp. based on internal transcribed spacer sequence homology. The cultivation of this fungus produced both cellulase (2.40 FPU/ml) and xylanase (241 IU/ml) on a stepwisely optimized medium at 30 °C for 144 h. The cellulase and xylanase from Penicillium sp. ECU0913 was stable at an ambient temperature with half-lives of 28 and 12 days, respectively. Addition of 3 M sorbitol greatly improved the thermostability of the two enzymes, with half-lives increased by 2.3 and 188-folds, respectively. Catalytic performance of the Penicillium cellulase and xylanase was evaluated by the hydrolysis of corn stover pretreated by steam explosion. With an enzyme dosage of 50 FPU/g dry substrate, the conversions of cellulose and hemicellulose reached 77.2% and 47.5%, respectively, without adding any accessory enzyme.

  2. Anaerobic co-digestion of chicken manure and corn stover in batch and continuously stirred tank reactor (CSTR).

    Science.gov (United States)

    Li, Yeqing; Zhang, Ruihong; He, Yanfeng; Zhang, Chenyu; Liu, Xiaoying; Chen, Chang; Liu, Guangqing

    2014-03-01

    Anaerobic co-digestion of chicken manure and corn stover in batch and CSTR were investigated. The batch co-digestion tests were performed at an initial volatile solid (VS) concentration of 3gVS/L, carbon-to-nitrogen (C/N) ratio of 20, and retention time of 30d. The methane yield was determined to be 281±12mL/gVSadded. Continuous reactor was carried out with feeding concentration of 12% total solids and C/N ratio of 20 at organic loading rates (OLRs) of 1-4gVS/L/d. Results showed that at OLR of 4gVS/L/d, stable and preferable methane yield of 223±7mL/gVSadded was found, which was equal to energy yield (EY) of 8.0±0.3MJ/kgVSadded. Post-digestion of digestate gave extra EY of 1.5-2.6MJ/kgVSadded. Pyrolysis of digestate provided additional EY of 6.1MJ/kgVSadded. Pyrolysis can be a promising technique to reduce biogas residues and to produce valuable gas products simultaneously. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. 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)

  4. Effects of biopretreatment of corn stover with white-rot fungus on low-temperature pyrolysis products.

    Science.gov (United States)

    Yang, Xuewei; Ma, Fuying; Yu, Hongbo; Zhang, Xiaoyu; Chen, Shulin

    2011-02-01

    The thermal decomposition of biopretreated corn stover during the low temperature has been studied by using the Py-GC/MS analysis and thermogravimetric analysis with the distributed activation energy model (DAEM). Results showed that biopretreatment with white-rot fungus Echinodontium taxodii 2538 can improve the low-temperature pyrolysis of biomass, by increasing the pyrolysis products of cellulose, hemicellulose (furfural and sucrose increased up to 4.68-fold and 2.94-fold respectively) and lignin (biophenyl and 3,7,11,15-tetramethyl-2-hexadecen-1-ol increased 2.45-fold and 4.22-fold, respectively). Calculated by DAEM method, it showed that biopretreatment can decrease the activation energy during the low temperature range, accelerate the reaction rate and start the thermal decomposition with lower temperature. ATR-FTIR results showed that the deconstruction of lignin and the decomposition of the main linkages between hemicellulose and lignin could contribute to the improvement of the pyrolysis at low temperature. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. Effect of biopretreatment on thermogravimetric and chemical characteristics of corn stover by different white-rot fungi.

    Science.gov (United States)

    Yang, Xuewei; Zeng, Yelin; Ma, Fuying; Zhang, Xiaoyu; Yu, Hongbo

    2010-07-01

    The thermogravimetric and chemical characterization of corn stover biopretreated by three different species of white-rot fungi have been studied in this research. Results indicated that biopretreatment can optimize the thermal decomposition, decrease the reaction temperature and reduce the gas contamination (SO(x)), making the biomass pyrolysis more efficient and environmentally friendly. Biopretreatment can decrease the activation energy and reacting temperature of the hemicellulose and cellulose pyrolysis (up to 36 degrees C), shorten the temperature range of the active pyrolysis (up to 14 degrees C), and increase the thermal decomposition rate, greatly promoting the reaction and making the biomass pyrolysis easier to start and carry on. On the other hand, by biopretreatment, the sulphur content can decrease up to 46.15%, which can considerably reduce the inventory of SO(x) emission. Moreover, the mechanism of the biopretreatment was also explored that the deconstruction and depolymerization of the recalcitrant linkages of lignin and cellulose by biopretreatment can make the structure of biomass incompact and easier to be pyrolyzed. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  6. Fast pyrolysis of corn stovers with ceramic ball heat carriers in a novel dual concentric rotary cylinder reactor.

    Science.gov (United States)

    Fu, Peng; Bai, Xueyuan; Li, Zhihe; Yi, Weiming; Li, Yongjun; Zhang, Yuchun

    2018-05-09

    Fast pyrolysis of corn stovers with ceramic ball heat carriers in a dual concentric rotary cylinder reactor was studied to explore the product yields and characteristics in response to temperature. The reactor was confirmed to successfully scale up to a 25 kg/h pilot plant, with its performance being excellent. The highest bio-oil yield of 48.3 wt% at 500 °C was attained with the char and gas yields being 26.8 and 24.9 wt%. Phenols content was reduced from 22.3% to 18.9% when elevating temperature from 450 until 600 °C, with guaiacols and alkyl phenols being the predominant compounds, while ketones accounted for 15.8-23.0% and their content showed a continuous increase, with hydroxyacetone being the paramount ketonic one. Acetic acid was the dominant acidic compound with its peak content of 9.4% at 500 °C. The char characteristics in response to temperatures were determined for subsequent processing and high value-added utilization. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Life cycle assessment of the production of hydrogen and transportation fuels from corn stover via fast pyrolysis

    Science.gov (United States)

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

    2013-06-01

    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 CO2eq and 0.015 kg CO2eq 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.

  8. Corn Stover and Wheat Straw Combustion in a 176-kW Boiler Adapted for Round Bales

    Directory of Open Access Journals (Sweden)

    Joey Villeneuve

    2013-11-01

    Full Text Available Combustion trials were conducted with corn stover (CS and wheat straw (WS round bales in a 176-kW boiler (model Farm 2000. Hot water (80 °C stored in a 30,000-L water tank was transferred to a turkey barn through a plate exchanger. Gross calorific value measured in the laboratory was 17.0 and 18.9 MJ/kg DM (dry matter for CS and WS, respectively. Twelve bales of CS (1974 kg DM total, moisture content of 13.6% were burned over a 52-h period and produced 9.2% ash. Average emissions of CO, NOx and SO2 were 2725, 9.8 and 2.1 mg/m3, respectively. Thermal efficiency was 40.8%. For WS, six bales (940 kg DM total, MC of 15% were burned over a 28-h period and produced 2.6% ash. Average emissions of CO, NOx and SO2 were 2210, 40.4 and 3.7 mg/m3, respectively. Thermal efficiency was 68.0%. A validation combustion trial performed a year later with 90 CS bales confirmed good heating performance and the potential to lower ash content (6.2% average.

  9. Enhanced biogas production from penicillin bacterial residue by thermal-alkaline pretreatment

    International Nuclear Information System (INIS)

    Zhong, Weizhang; Li, Guixia; Gao, Yan; Li, Zaixing; Geng, Xiaoling; Li, Yubing; Yang, Jingliang; Zhou, Chonghui

    2015-01-01

    In this study, the orthogonal experimental design was used to determine the optimum conditions for the effect of thermal alkaline; pretreatment on the anaerobic digestion of penicillin bacterial residue. The biodegradability of the penicillin; bacterial residue was evaluated by biochemical methane potential tests in laboratory. The optimum values of temperature,; alkali concentration, pretreatment time and moisture content for the thermal-alkaline pretreatment were determined as; 70 °C, 6% (w/v), 30 min, and 85%, respectively. Thermal-alkaline pretreatment could significantly enhance the soluble; chemical oxygen demand solubilization, the suspended solid solubilization and the biodegradability. Biogas production; was enhanced by the thermal-alkaline pretreatment, probably as a result of the breakdown of cell walls and membranes of; micro-organisms, which may facilitate the contact between organic molecules and anaerobic microorganisms.; Keywords: penicillin bacterial residue; anaerobic digestion; biochemical methane potential tests; pretreatment

  10. Lignocellulose degradation and enzyme production by Irpex lacteus CD2 during solid-state fermentation of corn stover.

    Science.gov (United States)

    Xu, Chunyan; Ma, Fuying; Zhang, Xiaoyu

    2009-11-01

    The white rot fungus Irpex lacteus CD2 was incubated on corn stover under solid-state fermentation conditions for different durations, from 5 days up to 120 days. Lignocellulose component loss, enzyme production and Fe3+-reducing activity were studied. The average weight loss ranged from 1.7% to 60.5% during the period of 5-120 days. In contrast to lignin, hemicellulose and cellulose were degraded during the initial time period. After 15 days, 63.0% of hemicellulose was degraded. Cellulose was degraded the most during the first 10 days, and 17.2% was degraded after 10 days. Lignin was significantly degraded and modified, with acid insoluble lignin loss being nearly 80% after 60 days. That weight loss, which was lower than the total component loss, indicated that not all of the lost lignocellulose was converted to carbon dioxide and water, which was indicated by the increase in soluble reducing sugars and acid soluble lignin. Filter paper activity, which corresponds to total cellulase activity, peaked at day 5 and remained at a high level from 40 to 60 days. High hemicellulase activity appeared after 30 days. No ligninases activity was detected during the incipient stage of lignin removal and only low lignin peroxidase activity was detected after 25 days. Apparently, neither of the enzymatic peaks coincided well with the highest amount of component loss. Fe3+-reducing activity could be detected during all the decay periods, which might play an important role in lignin biodegradation by I. lacteus CD2.

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

    Science.gov (United States)

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

    2018-01-01

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

  12. 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.

  13. Bed Agglomeration During the Steam Gasification of a High Lignin Corn Stover Simultaneous Saccharification and Fermentation (SSF) Digester Residue

    Energy Technology Data Exchange (ETDEWEB)

    Howe, Daniel T.; Taasevigen, Danny J.; Gerber, Mark A.; Gray, Michel J.; Fernandez, Carlos A.; Saraf, Laxmikant; Garcia-Perez, Manuel; Wolcott, Michael P.

    2015-11-13

    This research investigates the bed agglomeration phenomena during the steam gasification of a high lignin residue produced from the simultaneous saccharification and fermentation (SSF) of corn stover in a bubbling fluidized bed. The studies were conducted at 895°C using alumina as bed material. Biomass was fed at 1.5 kg/hr, while steam was fed to give a velocity equal to 2.5 times the minimum fluidization velocity, with a steam/carbon ratio of 0.9. The pelletized feedstock was co-fed with a cooling nitrogen stream to mitigate feed line plugging issues. Tar production was high at 50.3 g/Nm3, and the fraction of C10+ compounds was greater than that seen in the gasification of traditional lignocellulosic feedstocks. Carbon closures over 94 % were achieved for all experiments. Bed agglomeration was found to be problematic, indicated by pressure drop increases observed below the bed and upstream of the feed line. Two size categories of solids were recovered from the reactor, +60 mesh and -60 mesh. After a 2.75-hour experiment, 61.7 wt % was recovered as -60 mesh particles and 38.2 wt% of the recovered reactor solids were +60 mesh. A sizeable percentage, 31.8 wt%, was +20 mesh. The -60 mesh particles were mainly formed by the initial bed material (Al2O3). Almost 50 wt. % of the + 20 mesh particles was found to be formed by organics. The unreacted carbon remaining in the reactor resulted in a low conversion rate to product gas. ICP-AES, SEM, SEM-EDS, and XRD confirmed that the large agglomerates (+ 20 mesh) were not encapsulated bed material but rather un-gasified feedstock pellets with sand particles attached to it.

  14. 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.

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

    Science.gov (United States)

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

    2017-02-01

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

  16. Effects of co-digestion of cucumber residues to corn stover and pig manure ratio on methane production in solid state anaerobic digestion.

    Science.gov (United States)

    Wang, Yaya; Li, Guoxue; Chi, Menghao; Sun, Yanbo; Zhang, Jiaxing; Jiang, Shixu; Cui, Zongjun

    2018-02-01

    This study investigated the performance of co-digesting cucumber residues, corn stover, and pig manure at different ratios. Microbial community structure was analyzed to elucidate functional microorganism contributing to methane production during co-digestion. Results show that mixing cucumber residues with pig manure and corn stover could significantly improved methane yields 1.27-3.46 times higher than mono-feedstock. The methane yields decreased with the cucumber residues increasing when the pig manure ratio was fixed at 4 and 3, and was opposite at ratio 5. The optimal mixture ratio was T2 with the highest methane yield (305.4 mL/g VS) and co-digestion performance index (1.97). The main microbiological community in T2 was bacteria of Firmicutes (44.6%), Bacteroidetes (32.5%), Synergistetes (3.8%) and archaea of Methanosaeta (37.1%), Methanospirillum (18.2%). The mixture ratios changed the microbial community structures. The adding proportion of cucumber residues changed the community composition of the archaea, especially the proportion of Methanosaeta. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Novel DDR Processing of Corn Stover Achieves High Monomeric Sugar Concentrations from Enzymatic Hydrolysis (230 g/L) and High Ethanol Concentration (10% v/v) During Fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiaowen; Jennings, Ed; Shekiro, Joe; Kuhn, Erik M.; O' Brien, Marykate; Wang, Wei; Schell, Daniel J.; Himmel, Mike; Elander, Richard T.; Tucker, Melvin P.

    2015-04-03

    Distilling and purifying ethanol, butanol, and other products from second and later generation lignocellulosic biorefineries adds significant capital and operating cost for biofuels production. The energy costs associated with distillation affects plant gate and life cycle analysis costs. Lower titers in fermentation due to lower sugar concentrations from pretreatment increase both energy and production costs. In addition, higher titers decrease the volumes required for enzymatic hydrolysis and fermentation vessels. Therefore, increasing biofuels titers has been a research focus in renewable biofuels production for several decades. In this work, we achieved over 200 g/L of monomeric sugars after high solids enzymatic hydrolysis using the novel deacetylation and disc refining (DDR) process on corn stover. The high sugar concentrations and low chemical inhibitor concentrations from the DDR process allowed ethanol titers as high as 82 g/L in 22 hours, which translates into approximately 10 vol% ethanol. To our knowledge, this is the first time that 10 vol% ethanol in fermentation derived from corn stover without any sugar concentration or purification steps has been reported. Techno-economic analysis shows the higher titer ethanol achieved from the DDR process could significantly reduce the minimum ethanol selling price from cellulosic biomass.

  18. Kinetics of the pyrolysis of arundo, sawdust, corn stover and switch grass biomass by thermogravimetric analysis using a multi-stage model.

    Science.gov (United States)

    Biney, Paul O; Gyamerah, Michael; Shen, Jiacheng; Menezes, Bruna

    2015-03-01

    A new multi-stage kinetic model has been developed for TGA pyrolysis of arundo, corn stover, sawdust and switch grass that accounts for the initial biomass weight (W0). The biomass were decomposed in a nitrogen atmosphere from 23°C to 900°C in a TGA at a single 20°C/min ramp rate in contrast with the isoconversion technique. The decomposition was divided into multiple stages based on the absolute local minimum values of conversion derivative, (dx/dT), obtained from DTG curves. This resulted in three decomposition stages for arundo, corn stover and sawdust and four stages for switch grass. A linearized multi-stage model was applied to the TGA data for each stage to determine the pre-exponential factor, activation energy, and reaction order. The activation energies ranged from 54.7 to 60.9 kJ/mol, 62.9 to 108.7 kJ/mol, and 18.4 to 257.9 kJ/mol for the first, second and the third decomposition stages respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Effects of replacing wild rye, corn silage, or corn grain with CaO-treated corn stover and dried distillers grains with solubles in lactating cow diets on performance, digestibility, and profitability.

    Science.gov (United States)

    Shi, H T; Li, S L; Cao, Z J; Wang, Y J; Alugongo, G M; Doane, P H

    2015-10-01

    The objective of this study was to measure the effects of partially replacing wild rye (Leymus chinensis; WR), corn silage (CS), or corn grain (CG) in dairy cow diets with CaO-treated corn stover (T-CS) and corn dried distillers grains with soluble (DDGS) on performance, digestibility, blood metabolites, and income over feed cost. Thirty tonnes of air-dried corn stover was collected, ground, and mixed with 5% CaO. Sixty-four Holstein dairy cows were blocked based on days in milk, milk yield, and parity and were randomly assigned to 1 of 4 treatments. The treatments were (1) a diet containing 50% concentrate, 15% WR, 25% CS, and 10% alfalfa hay (CON); (2) 15% WR, 5% CG, and 6% soybean meal were replaced by 15% T-CS and 12% DDGS (RWR); (3) 12.5% CS, 6% CG, and 5% soybean meal were replaced by 12.5% T-CS and 12%DDGS (RCS); (4) 13% CG and 6% soybean meal were replaced by 7% T-CS and 13% DDGS (RCG). Compared with CON treatment, cows fed RCS and RCG diets had similar dry matter intake (CON: 18.2 ± 0.31 kg, RCS: 18.6 ± 0.31 kg, and RCG: 18.4 ± 0.40 kg). The RWR treatment tended to have lower dry matter intake than other treatments. The inclusion of T-CS and DDGS in treatment diets as a substitute for WR, CS, or CG had no effects on lactose percentage (CON: 4.96 ± 0.02%, RWR: 4.97 ± 0.02%, RCS: 4.96 ± 0.02%, and RCG: 4.94 ± 0.02%), 4% fat-corrected milk yield (CON: 22.7 ± 0.60 kg, RWR: 22.1 ± 0.60 kg, RCS: 22.7 ± 0.60 kg, and RCG: 22.7 ± 0.60 kg), milk fat yield (CON: 0.90 ± 0.03 kg, RWR: 0.86 ± 0.03 kg, RCS: 0.87 ± 0.03 kg, and RCG: 0.89 ± 0.03 kg), and milk protein yield (CON: 0.74 ± 0.02 kg, RWR: 0.72 ± 0.02 kg, RCS: 0.73 ± 0.02 kg, and RCG: 0.71 ± 0.02 kg). Cows fed the RWR diet had higher apparent dry matter digestibility (73.7 ± 1.30 vs. 70.2 ± 1.15, 69.9 ± 1.15, and 69.9 ± 1.15% for RWR vs. CON, RCS, and RCG, respectively) and lower serum urea N (3.55 ± 0.11 vs. 4.03 ± 0.11, 3.95 ± 0.11, and 3.99 ± 0.11 mmol/L for RWR vs. CON, RCS, and RCG

  20. 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.

  1. 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.

  2. Effects of the dietary nonfiber carbohydrate content on lactation performance, rumen fermentation, and nitrogen utilization in mid-lactation dairy cows receiving corn stover.

    Science.gov (United States)

    Wei, Zihai; Zhang, Baoxin; Liu, Jianxin

    2018-01-01

    Corn stover (CS) is an abundant source of feed for livestock in China. However, it is low in nutritional value that we have been seeking technologies to improve. Previous studies show that non-fiber carbohydrate (NFC) might limit the utilization of a CS diet by lactating dairy cows. Thus, this study was conducted to investigate the lactation performance and rumen fermentation characteristics in lactating cows consuming CS with two contents of NFC compared to an alfalfa hay-containing diet. Twelve Holstein cows were used in a replicated 3 × 3 Latin square design with three dietary treatments: (1) low-NFC diet (NFC = 35.6%, L-NFC), (2) high-NFC diet (NFC = 40.1%, H-NFC), and (3) alfalfa hay diet (NFC = 38.9%, AH). Intake of DM was lower for cows fed H-NFC compared to L-NFC and AH, while the milk yield was higher in AH than in H-NFC and L-NFC ( P  contents of milk protein and lactose were not different among the groups ( P  > 0.11), but milk fat content was higher for cows fed H-NFC and L-NFC compared to AH ( P  rumen ammonia nitrogen concentration and the concentrations of urea nitrogen in blood and milk were lower for cows fed H-NFC and AH compared to L-NFC ( P  rumen propionate and total volatile fatty acids were different among groups ( P  content in a diet containing corn stover can improve the feed efficiency and benefit the nitrogen conversion.

  3. Short communication. Effects of adding different protein and carbohydrates sources on chemical composition and in vitro gas production of corn stover silage

    Directory of Open Access Journals (Sweden)

    L. A. Mejía-Uribe

    2013-05-01

    Full Text Available The use of protein-rich by-products based in swine manure (SM, poultry waste (PW or chemicals compounds as urea (U, as well as energy products like molasses (M and bakery by-product (BB, is a viable method to produce good quality silage. In addition, the use of a bacterial additive can improve the fermentation characteristics of silage. The objective of this study was to determine chemical composition, in vitro gas production (GP and dry matter disappearance (DMd, using different sources of protein and energy in silage. The silages were made using SM, PW or U as protein sources and M or BB as energy source, with corn stover and with or without a bacterial additive. The organic matter (OM content was higher (p < 0.001 in silages with UBB, UM and SMBB compared with the rest of the treatments; meanwhile crude protein content was higher (p < 0.001 in silages with U. The addition of a bacterial additive increased (p < 0.05 OM content and decreased (p < 0.05 fiber content. Total GP was higher (p < 0.05 in silages containing BB, but DMd was higher (p < 0.05 in silages with U and SMBB. The inclusion of a bacterial additive decreased (p < 0.05 GP and DMd. The use of alternative sources of protein such as poultry and swine manure or urea, and of by-products of sugar industry and bakery is an alternative for silages based on corn stover. The results show that when properly formulated, the silages can provide more than 16% of crude protein and have DMd values above 60%.

  4. Fast pyrolysis of corn stover using ZnCl2: Effect of washing treatment on the furfural yield and solvent extraction of furfural

    International Nuclear Information System (INIS)

    Oh, Seung-Jin; Choi, Gyung-Goo; Kim, Joo-Sik

    2015-01-01

    To produce a bio-oil having a high concentration of furfural, corn stover was fast-pyrolyzed using ZnCl 2 in a fluidized bed reactor at 330–430 °C. The effects of various parameters such as reaction temperature, water- and acid-washing prior to pyrolysis, and ZnCl 2 content on the product and furfural yields were investigated. Moreover, solvent extraction was conducted using toluene at different mass ratios of bio-oil/toluene to recover furfural from the obtained bio-oil. The maximum yield of bio-oil was 59 wt%. The bio-oil mainly comprised acetic acid, α-hydroxyketones, and furfural. The maximum furfural yield was 11.5 wt% when the feed material was water-washed, impregnated with 18.5 wt% ZnCl 2 , and pyrolyzed. Although acid-washing removed alkali and alkaline earth metals much more efficiently than water-washing, water-washing was better than acid-washing for the furfural production. Toluene extraction was very effective to recover furfural from bio-oil. The maximum recovery rate (82%) was achieved at a bio-oil/toluene ratio of 1:4. - Highlights: • Corn stover pretreated and impregnated with ZnCl 2 was successfully pyrolyzed. • Furfural was recovered from bio-oil by extraction using toluene. • Water-washing was better than acid-washing for the furfural production. • The highest furfural yield was 11.5 wt% of the product. • The highest furfural recovery rate was 82%

  5. Improving methane production from digested manure biofibers by mechanical and thermal alkaline pretreatment

    DEFF Research Database (Denmark)

    Tsapekos, Panagiotis; Kougias, Panagiotis; Frison, A.

    2016-01-01

    the effluent stream of biogas reactors. Batch and continuous experiments were conducted to evaluate the efficiency of these pretreatments. In batch experiments, the mechanical pretreatment improved the degradability up to 45%. Even higher efficiency was shown by applying thermal alkaline pretreatments...

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. Combined Mechanical Destruction and Alkaline Pretreatment of Wheat Straw for Enhanced Enzymatic Saccharification

    Directory of Open Access Journals (Sweden)

    Qianqian Wang

    2014-09-01

    Full Text Available Wheat straw was pretreated by combined mechanical destruction and alkaline pretreatments to enhance enzymatic saccharification. Four strategies were employed to evaluate the potential of wheat straw as a feedstock for fermentable sugar production. The effects of the pretreatments on the substrate morphology, size distribution, chemical composition, and cellulose crystallinity, along with the subsequent enzymatic digestibility, were investigated. Optical microscope images showed that mechanical pretreatment alone resulted in poor fiber defibrillation, wherein samples mostly consisted of rigid fiber bundles, while integrated mechanical destruction and alkaline pretreatment led to relatively good fiber defibrillation. Low temperature NaOH/urea pretreatment can fibrillate the rigid fiber bundles into a relatively loose network and alter the structure of the treated substrate to make cellulose more accessible. The glucan conversion rates were 77% and 95% for integrated mechanical destruction and alkaline pretreatments and mechanical destruction followed by low temperature NaOH/urea and ammonium/urea pretreatments, respectively, after 72 h of enzymatic hydrolysis with enzyme loadings of 10 FPU cellulase per g of oven-dry substrate.

  11. 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

  12. Modulation of the Acetone/Butanol Ratio during Fermentation of Corn Stover-Derived Hydrolysate by Clostridium beijerinckii Strain NCIMB 8052.

    Science.gov (United States)

    Liu, Zi-Yong; Yao, Xiu-Qing; Zhang, Quan; Liu, Zhen; Wang, Ze-Jie; Zhang, Yong-Yu; Li, Fu-Li

    2017-04-01

    Producing biobutanol from lignocellulosic biomass has shown promise to ultimately reduce greenhouse gases and alleviate the global energy crisis. However, because of the recalcitrance of a lignocellulosic biomass, a pretreatment of the substrate is needed which in many cases releases soluble lignin compounds (SLCs), which inhibit growth of butanol-producing clostridia. In this study, we found that SLCs changed the acetone/butanol ratio (A/B ratio) during butanol fermentation. The typical A/B molar ratio during Clostridium beijerinckii NCIMB 8052 batch fermentation with glucose as the carbon source is about 0.5. In the present study, the A/B molar ratio during batch fermentation with a lignocellulosic hydrolysate as the carbon source was 0.95 at the end of fermentation. Structural and redox potential changes of the SLCs were characterized before and after fermentation by using gas chromatography/mass spectrometry and electrochemical analyses, which indicated that some exogenous SLCs were involved in distributing electron flow to C. beijerinckii , leading to modulation of the redox balance. This was further demonstrated by the NADH/NAD + ratio and trxB gene expression profile assays at the onset of solventogenic growth. As a result, the A/B ratio of end products changed significantly during C. beijerinckii fermentation using corn stover-derived hydrolysate as the carbon source compared to glucose as the carbon source. These results revealed that SLCs not only inhibited cell growth but also modulated the A/B ratio during C. beijerinckii butanol fermentation. IMPORTANCE Bioconversion of lignocellulosic feedstocks to butanol involves pretreatment, during which hundreds of soluble lignin compounds (SLCs) form. Most of these SLCs inhibit growth of solvent-producing clostridia. However, the mechanism by which these compounds modulate electron flow in clostridia remains elusive. In this study, the results revealed that SLCs changed redox balance by producing oxidative

  13. 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

  14. Tissue-specific biomass recalcitrance in corn stover pretreated with liquid hot-water: enzymatic hydrolysis (part 1).

    Science.gov (United States)

    Zeng, Meijuan; Ximenes, Eduardo; Ladisch, Michael R; Mosier, Nathan S; Vermerris, Wilfred; Huang, Chia-Ping; Sherman, Debra M

    2012-02-01

    Lignin content, composition, distribution as well as cell wall thickness, structures, and type of tissue have a measurable effect on enzymatic hydrolysis of cellulose in lignocellulosic feedstocks. The first part of our work combined compositional analysis, pretreatment and enzyme hydrolysis for fractionated pith, rind, and leaf tissues from a hybrid stay-green corn, in order to identify the role of structural characteristics on enzyme hydrolysis of cell walls. The extent of enzyme hydrolysis follows the sequence rind cellulose to glucose in 24 h in the best cases. Physical fractionation of corn stalks or other C(4) grasses into soft and hard tissue types could reduce cost of cellulose conversion by enabling reduced enzyme loadings to hydrolyze soft tissue, and directing the hard tissue to other uses such as thermal processing, combustion, or recycle to the land from which the corn was harvested. Copyright © 2011 Wiley Periodicals, Inc.

  15. Ammonium, Nitrate, and Phosphate Sorption to and Solute Leaching from Biochars Prepared from Corn Stover ( L.) and Oak Wood ( spp.).

    Science.gov (United States)

    Hollister, C Colin; Bisogni, James J; Lehmann, Johannes

    2013-01-01

    Biochar (BC) was evaluated for nitrogen (N) and phosphorus (P) removal from aqueous solution to quantify its nutrient pollution mitigation potential in agroecosystems. Sorption isotherms were prepared for solutions of ammonium (NH), nitrate (NO), and phosphate (PO-P) using BC of corn ( L.) and oak ( spp.) feedstock, each pyrolyzed at 350 and 550°C highest treatment temperature (HTT). Sorption experiments were performed on original BC as well as on BC that went through a water extraction pretreatment (denoted WX-BC). Ammonium sorption was observed for WX-Oak-BC and WX-Corn-BC, and Freundlich model linearization showed that a 200°C increase in HTT resulted in a 55% decrease in * values for WX-Oak-BC and a 69% decrease in * for WX-Corn-BC. Nitrate sorption was not observed for any BC. Removing metals by water extraction from WX-Oak-350 and WX-Oak-550 resulted in a 25 to 100% decrease in phosphate removal efficiency relative to original Oak-350 and Oak-550, respectively. No PO-P sorption was observed using any Corn-BC. Calcium (Ca) leached from BC produced at 550°C was 63 and 104% higher than from BC produced at 350°C for corn and oak, respectively. Leaching of P was two orders of magnitude lower in WX-Oak-BC than in WX-Corn-BC, concurrent with similar difference in magnesium (Mg). Nitrate and NH leaching from consecutive water extractions of all tested BCs was mostly below detection limits. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  16. The effect of lignin removal by alkaline peroxide pretreatment on the susceptibility of corn stover to purified cellulolytic and xylanolytic enzymes.

    Science.gov (United States)

    Selig, Michael J; Vinzant, Todd B; Himmel, Michael E; Decker, Stephen R

    2009-05-01

    Pretreatment of corn stover with alkaline peroxide (AP) at pH 11.5 resulted in reduction of lignin content in the residual solids as a function of increasing batch temperature. Scanning electron microscopy of these materials revealed notably more textured surfaces on the plant cell walls as a result of the delignifying pretreatment. As expected, digestion of the delignified samples with commercial cellulase preparations showed an inverse relationship between the content of lignin present in the residual solids after pretreatment and the extent of both glucan and xylan conversion achievable. Digestions with purified enzymes revealed that decreased lignin content in the pretreated solids did not significantly impact the extent of glucan conversion achievable by cellulases alone. Not until purified xylanolytic activities were included with the cellulases were significant improvements in glucan conversion realized. In addition, an inverse relationship was observed between lignin content after pretreatment and the extent of xylan conversion achievable in a 24-h period with the xylanolytic enzymes in the absence of the cellulases. This observation, coupled with the direct relationship between enzymatic xylan and glucan conversion observed in a number of cases, suggests that the presence of lignins may not directly occlude cellulose present in lignocelluloses but rather impact cellulase action indirectly by its association with xylan.

  17. Evaluation of soluble fraction and enzymatic residual fraction of dilute dry acid, ethylenediamine, and steam explosion pretreated corn stover on the enzymatic hydrolysis of cellulose.

    Science.gov (United States)

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

    2016-06-01

    This study is aimed to examine the inhibition of soluble fraction (SF) and enzymatic residual fraction (ERF) in dry dilute acid (DDA), ethylenediamine (EDA) and steam explosion (SE) pretreated corn stover (CS) on the enzymatic digestibility of cellulose. SF of DDA, EDA and SE pretreated CS has high xylose, soluble lignin and xylo-oligomer content, respectively. SF of EDA pretreated CS leads to the highest inhibition, followed by SE and DDA pretreated CS. Inhibition of ERF of DDA and SE pretreated CS is higher than that of EDA pretreated CS. The inhibition degree (A0/A) of SF is 1.76 and 1.21 times to that of ERF for EDA and SE pretreated CS, respectively. The inhibition degree of ERF is 1.05 times to that of SF in DDA pretreated CS. The quantitative analysis shows that SF of EDA pretreated CS, SF and ERF of SE pretreated CS cause significant inhibition during enzymatic hydrolysis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Effect of pretreatment severity on accumulation of major degradation products from dilute acid pretreated corn stover and subsequent inhibition of enzymatic hydrolysis of cellulose.

    Science.gov (United States)

    Um, Byung-Hwan; van Walsum, G Peter

    2012-09-01

    The concept of reaction severity, which combines residence time and temperature, is often used in the pulp and paper and biorefining industries. The influence of corn stover pretreatment severity on yield of sugar and major degradation products and subsequent effects on enzymatic cellulose hydrolysis was investigated. The pretreatment residence time and temperature, combined into the severity factor (Log R(o)), were varied with constant acid concentration. With increasing severity, increasing concentrations of furfural and 5-hydroxymethylfurfural (5-HMF) coincided with decreasing yields of oligosaccharides. With further increase in severity factor, the concentrations of furans decreased, while the formation of formic acid and lactic acid increased. For example, from severity 3.87 to 4.32, xylose decreased from 6.39 to 5.26 mg/mL, while furfural increased from 1.04 to 1.33 mg/mL; as the severity was further increased to 4.42, furfural diminished to 1.23 mg/mL as formate rose from 0.62 to 1.83 mg/mL. The effects of dilute acid hydrolyzate, acetic acid, and lignin, in particular, on enzymatic hydrolysis were investigated with a rapid microassay method. The microplate method gave considerable time and cost savings compared to the traditional assay protocol, and it is applicable to a broad range of lignocellulosic substrates.

  19. Conditioning of dilute-acid pretreated corn stover hydrolysate liquors by treatment with lime or ammonium hydroxide to improve conversion of sugars to ethanol.

    Science.gov (United States)

    Jennings, Edward W; Schell, Daniel J

    2011-01-01

    Dilute-acid pretreatment of lignocellulosic biomass enhances the ability of enzymes to hydrolyze cellulose to glucose, but produces many toxic compounds that inhibit fermentation of sugars to ethanol. The objective of this study was to compare the effectiveness of treating hydrolysate liquor with Ca(OH)2 and NH4OH for improving ethanol yields. Corn stover was pretreated in a pilot-scale reactor and then the liquor fraction (hydrolysate) was extracted and treated with various amounts of Ca(OH)2 or NH4OH at several temperatures. Glucose and xylose in the treated liquor were fermented to ethanol using a glucose-xylose fermenting bacteria, Zymomonas mobilis 8b. Sugar losses up to 10% occurred during treatment with Ca(OH)2, but these losses were two to fourfold lower with NH4OH treatment. Ethanol yields for NH4OH-treated hydrolysate were 33% greater than those achieved in Ca(OH)2-treated hydrolysate and pH adjustment to either 6.0 or 8.5 with NH4OH prior to fermentation produced equivalent ethanol yields. Copyright © 2010 Elsevier Ltd. All rights reserved.

  20. Kinetic characterization for hemicellulose hydrolysis of corn stover in a dilute acid cycle spray flow-through reactor at moderate conditions

    International Nuclear Information System (INIS)

    Jin, Qiang; Zhang, Hongman; Yan, Lishi; Qu, Liang; Huang, He

    2011-01-01

    The kinetic characterization of hemicellulose hydrolysis of corn stover was investigated using a new reactor of dilute acid cycle spray flow-through (DCF) pretreatment. The primary purpose was to obtain kinetic data for hemicellulose hydrolysis with sulfuric acid concentrations (10-30 kg m -3 ) at relatively low temperatures (90-100 o C). A simplified kinetic model was used to describe its performance at moderate conditions. The results indicate that the rates of xylose formation and degradation are sensitive to flow rate, temperature and acid concentration. Moreover, the kinetic data of hemicellulose hydrolysis fit a first-order reaction model and the experimental data with actual acid concentration after accounting for the neutralization effect of the substrates at different temperatures. Over 90% of the xylose monomer yield and below 5.5% of degradation product (furfural) yield were observed in this reactor. Kinetic constants for hemicellulose hydrolysis models were analyzed by an Arrhenius-type equation, and the activation energy of xylose formation were 111.6 kJ mol -1 , and 95.7 kJ mol -1 for xylose degradation, respectively. -- Highlights: → Investigating a novel pretreatment reactor of dilute acid cycle spray flow-through. → Xylose yield is sensitive to flow rate, temperature and acid concentration. → Obtaining relatively higher xylose monomer yield and lower fermentation inhibitor. → Lumping hemicellulose and xylan oligmers together in the model is a valid way. → The kinetic model as a guide for reactor design, and operation strategy optimization.

  1. Supplementation with xylanase and β-xylosidase to reduce xylo-oligomer and xylan inhibition of enzymatic hydrolysis of cellulose and pretreated corn stover

    Science.gov (United States)

    2011-01-01

    Background Hemicellulose is often credited with being one of the important physical barriers to enzymatic hydrolysis of cellulose, and acts by blocking enzyme access to the cellulose surface. In addition, our recent research has suggested that hemicelluloses, particularly in the form of xylan and its oligomers, can more strongly inhibit cellulase activity than do glucose and cellobiose. Removal of hemicelluloses or elimination of their negative effects can therefore become especially pivotal to achieving higher cellulose conversion with lower enzyme doses. Results In this study, cellulase was supplemented with xylanase and β-xylosidase to boost conversion of both cellulose and hemicellulose in pretreated biomass through conversion of xylan and xylo-oligomers to the less inhibitory xylose. Although addition of xylanase and β-xylosidase did not necessarily enhance Avicel hydrolysis, glucan conversions increased by 27% and 8% for corn stover pretreated with ammonia fiber expansion (AFEX) and dilute acid, respectively. In addition, adding hemicellulase several hours before adding cellulase was more beneficial than later addition, possibly as a result of a higher adsorption affinity of cellulase and xylanase to xylan than glucan. Conclusions This key finding elucidates a possible mechanism for cellulase inhibition by xylan and xylo-oligomers and emphasizes the need to optimize the enzyme formulation for each pretreated substrate. More research is needed to identify advanced enzyme systems designed to hydrolyze different substrates with maximum overall enzyme efficacy. PMID:21702938

  2. On-site cellulase production and efficient saccharification of corn stover employing cbh2 overexpressing Trichoderma reesei with novel induction system.

    Science.gov (United States)

    Li, Yonghao; Zhang, Xiaoyue; Xiong, Liang; Mehmood, Muhammad Aamer; Zhao, Xinqing; Bai, Fengwu

    2017-08-01

    Although on-site cellulase production offers cost-effective saccharification of lignocellulosic biomass, low enzyme titer is still a barrier for achieving robustness. In the present study, a strain of T. reesei was developed for enhanced production of cellulase via overexpression of Cellobiohydrolase II. Furthermore, optimum enzyme production was achieved using a novel inducer mixture containing synthesized glucose-sophorose (MGD) and alkali pre-treated corn stover (APCS). Within 60h, a remarkably higher cellulase productivity and activity were achieved in the fed-batch fermentation using the optimized ratio of MGD and APCS in the inducer mixture, compared to those reported using cellulosic biomass as the sole inducer. After the enzyme production, APCS was added directly into the fermentation broth at 20% solid loading, which produced 122.5g/L glucose and 40.21g/L xylose, leading to the highest yield reported so far. The improved enzyme titers during on-site cellulase production would benefit cost-competitive saccharification of lignocellulosic biomass. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Comparison of varying operating parameters on heavy metals ecological risk during anaerobic co-digestion of chicken manure and corn stover.

    Science.gov (United States)

    Yan, Yilong; Zhang, Liqiu; Feng, Li; Sun, Dezhi; Dang, Yan

    2018-01-01

    In this study, the potential ecological risk of heavy metals (Mn, Zn, Cu, Ni, As, Cd, Pb, Cr) accumulation from anaerobic co-digestion of chicken manure (CM) and corn stover (CS) was evaluated by comparing different initial substrate concentrations, digestion temperatures, and mixture ratios. Results showed that the highest volumetric methane yield of 20.3±1.4L/L reactor was achieved with a CS:CM ratio of 3:1 (on volatile solid basis) in mesophilic solid state anaerobic digestion (SS-AD). Although co-digestion increased the concentrations of all tested heavy metals and the direct toxicity of some heavy metals, the potential ecological risk index indicated that the digestates were all classified as low ecological risk. The biogasification and risk variation of heavy metals were affected by the operating parameters. These results are significant and should be taken into consideration when optimizing co-digestion of animal manure and crop residues during full-scale projects. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. 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 $2.15/gal in 2007$.

  5. Understanding the synergistic effect and the main factors influencing the enzymatic hydrolyzability of corn stover at low enzyme loading by hydrothermal and/or ultrafine grinding pretreatment.

    Science.gov (United States)

    Zhang, Haiyan; Li, Junbao; Huang, Guangqun; Yang, Zengling; Han, Lujia

    2018-05-26

    A thorough assessment of the microstructural changes and synergistic effects of hydrothermal and/or ultrafine grinding pretreatment on the subsequent enzymatic hydrolysis of corn stover was performed in this study. The mechanism of pretreatment was elucidated by characterizing the particle size, specific surface area (SSA), pore volume (PV), average pore size, cellulose crystallinity (CrI) and surface morphology of the pretreated samples. In addition, the underlying relationships between the structural parameters and final glucose yields were elucidated, and the relative significance of the factors influencing enzymatic hydrolyzability were assessed by principal component analysis (PCA). Hydrothermal pretreatment at a lower temperature (170 °C) combined with ultrafine grinding achieved a high glucose yield (80.36%) at a low enzyme loading (5 filter paper unit (FPU)/g substrate) which is favorable. The relative significance of structural parameters in enzymatic hydrolyzability was SSA > PV > average pore size > CrI/cellulose > particle size. PV and SSA exhibited logarithmic correlations with the final enzymatic hydrolysis yield. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Supplementation with xylanase and β-xylosidase to reduce xylo-oligomer and xylan inhibition of enzymatic hydrolysis of cellulose and pretreated corn stover

    Directory of Open Access Journals (Sweden)

    Qing Qing

    2011-06-01

    Full Text Available Abstract Background Hemicellulose is often credited with being one of the important physical barriers to enzymatic hydrolysis of cellulose, and acts by blocking enzyme access to the cellulose surface. In addition, our recent research has suggested that hemicelluloses, particularly in the form of xylan and its oligomers, can more strongly inhibit cellulase activity than do glucose and cellobiose. Removal of hemicelluloses or elimination of their negative effects can therefore become especially pivotal to achieving higher cellulose conversion with lower enzyme doses. Results In this study, cellulase was supplemented with xylanase and β-xylosidase to boost conversion of both cellulose and hemicellulose in pretreated biomass through conversion of xylan and xylo-oligomers to the less inhibitory xylose. Although addition of xylanase and β-xylosidase did not necessarily enhance Avicel hydrolysis, glucan conversions increased by 27% and 8% for corn stover pretreated with ammonia fiber expansion (AFEX and dilute acid, respectively. In addition, adding hemicellulase several hours before adding cellulase was more beneficial than later addition, possibly as a result of a higher adsorption affinity of cellulase and xylanase to xylan than glucan. Conclusions This key finding elucidates a possible mechanism for cellulase inhibition by xylan and xylo-oligomers and emphasizes the need to optimize the enzyme formulation for each pretreated substrate. More research is needed to identify advanced enzyme systems designed to hydrolyze different substrates with maximum overall enzyme efficacy.

  7. Engineering and two-stage evolution of a lignocellulosic hydrolysate-tolerant Saccharomyces cerevisiae strain for anaerobic fermentation of xylose from AFEX pretreated corn stover.

    Directory of Open Access Journals (Sweden)

    Lucas S Parreiras

    Full Text Available The inability of the yeast Saccharomyces cerevisiae to ferment xylose effectively under anaerobic conditions is a major barrier to economical production of lignocellulosic biofuels. Although genetic approaches have enabled engineering of S. cerevisiae to convert xylose efficiently into ethanol in defined lab medium, few strains are able to ferment xylose from lignocellulosic hydrolysates in the absence of oxygen. This limited xylose conversion is believed to result from small molecules generated during biomass pretreatment and hydrolysis, which induce cellular stress and impair metabolism. Here, we describe the development of a xylose-fermenting S. cerevisiae strain with tolerance to a range of pretreated and hydrolyzed lignocellulose, including Ammonia Fiber Expansion (AFEX-pretreated corn stover hydrolysate (ACSH. We genetically engineered a hydrolysate-resistant yeast strain with bacterial xylose isomerase and then applied two separate stages of aerobic and anaerobic directed evolution. The emergent S. cerevisiae strain rapidly converted xylose from lab medium and ACSH to ethanol under strict anaerobic conditions. Metabolomic, genetic and biochemical analyses suggested that a missense mutation in GRE3, which was acquired during the anaerobic evolution, contributed toward improved xylose conversion by reducing intracellular production of xylitol, an inhibitor of xylose isomerase. These results validate our combinatorial approach, which utilized phenotypic strain selection, rational engineering and directed evolution for the generation of a robust S. cerevisiae strain with the ability to ferment xylose anaerobically from ACSH.

  8. Phytotoxicity assessment on corn stover biochar, derived from fast pyrolysis, based on seed germination, early growth, and potential plant cell damage.

    Science.gov (United States)

    Li, Yang; Shen, Fei; Guo, Haiyan; Wang, Zhanghong; Yang, Gang; Wang, Lilin; Zhang, Yanzong; Zeng, Yongmei; Deng, Shihuai

    2015-06-01

    The potential phytotoxicity of water extractable toxicants in a typical corn stover biochar, the product of fast pyrolysis, was investigated using an aqueous biochar extract on a soil-less bioassay with tomato plants. The biochar dosage of 0.0-16.0 g beaker(-1) resulted in an inverted U-shaped dose-response relationship between biochar doasage and seed germination/seedling growth. This indicated that tomato growth was slightly stimulated by low dosages of biochar and inhibited with higher dosages of biochar. Additionally, antioxidant enzyme activities in the roots and leaves were enhanced at lower dosages, but rapidly decreased with higher dosages of biochar. With the increased dosages of biochar, the malondialdehyde content in the roots and leaves increased, in addition with the observed morphology of necrotic root cells, suggesting that serious damage to tomato seedlings occurred. EC50 of root length inhibition occurred with biochar dosages of 9.2 g beaker(-1) (3.5th day) and 16.7 g beaker(-1) (11th day) (equivalent to 82.8 and 150.3 t ha(-1), respectively), which implied that toxicity to the early growth of tomato can potentially be alleviated as the plant grows.

  9. Conversion of Corn Stover Hydrolysates to Acids: Comparison Between Clostridium carboxidivorans P7 and Microbial Communities Developed from Lake Sediment and an Anaerobic Digester

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiaowen [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Tucker, Melvin P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Xia, Chunjie [Southern Illinois University; Kumar, Aditi [Carbondale Community High School; Liang, Yanna [Southern Illinois University

    2017-01-18

    Anaerobic fermentation is an environmentally sustainable technology for converting a variety of feedstocks to biofuels and bioproducts. Considering the complex nature of lignocellulosic hydrolysates, we aimed to investigate product formation from corn stover hydrolysates by using microbial communities under anaerobic conditions. A community developed from lake sediment was able to produce lactic acid from only glucose in the raw or overlimed hydrolysates. Another community from an anaerobic digester, however, was capable of using all hexose and pentose sugars in the raw and undetoxified hydrolysates and released lactic acid at 26.76 g/L. A pure acetogen, Clostridium carboxidivorans P7, was able to grow on the raw and overlimed hydrolysates, too. But the consumption of sugars was minimal and the total released acid concentrations were less than 2 g/L. Next generation sequencing of the enriched community derived from the anaerobic digester revealed the presence of Lactobacillus strains. The predominant species were Lactobacillus parafarraginis (72.6%) and L. buchneri (13.4%). Product titer from using this enriched community can be further enhanced by cultivating at fed-batch or continuous fermentation modes. Results from this study widened the door for producing valuable products from lignocellulosic feedstocks through using mixed cultures.

  10. NREL 2012 Achievement of Ethanol Cost Targets: Biochemical Ethanol Fermentation via Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Tao, L.; Schell, D.; Davis, R.; Tan, E.; Elander, R.; Bratis, A.

    2014-04-01

    For the DOE Bioenergy Technologies Office, the annual State of Technology (SOT) assessment is an essential activity for quantifying the benefits of biochemical platform research. This assessment has historically allowed the impact of research progress achieved through targeted Bioenergy Technologies Office funding to be quantified in terms of economic improvements within the context of a fully integrated cellulosic ethanol production process. As such, progress toward the ultimate 2012 goal of demonstrating cost-competitive cellulosic ethanol technology can be tracked. With an assumed feedstock cost for corn stover of $58.50/ton this target has historically been set at $1.41/gal ethanol for conversion costs only (exclusive of feedstock) and $2.15/gal total production cost (inclusive of feedstock) or minimum ethanol selling price (MESP). This year, fully integrated cellulosic ethanol production data generated by National Renewable Energy Laboratory (NREL) researchers in their Integrated Biorefinery Research Facility (IBRF) successfully demonstrated performance commensurate with both the FY 2012 SOT MESP target of $2.15/gal (2007$, $58.50/ton feedstock cost) and the conversion target of $1.41/gal through core research and process improvements in pretreatment, enzymatic hydrolysis, and fermentation.

  11. [Corn.

    Science.gov (United States)

    Iowa History for Young People, 1993

    1993-01-01

    This theme issue focuses on corn. Iowa is the number one corn producing state in the United States. The featured articles in the issue concern, among other topics, Iowa children who live on farms, facts and statistics about corn, the Mesquakie Indians and corn shelling, corn hybrids, a short story, and the corn palaces of Sioux City. Activities,…

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

    OpenAIRE

    Andras Dallos; Gyula Dörgő; Dániel Capári

    2016-01-01

    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 pretrea...

  13. Comparison of different liquid anaerobic digestion effluents as inocula and nitrogen sources for solid-state batch anaerobic digestion of corn stover

    International Nuclear Information System (INIS)

    Xu Fuqing; Shi Jian; Lv Wen; Yu Zhongtang; Li Yebo

    2013-01-01

    Highlights: ► Compared methane production of solid AD inoculated with different effluents. ► Food waste effluent (FWE) had the largest population of acetoclastic methanogens. ► Solid AD inoculated with FWE produced the highest methane yield at F/E ratio of 4. ► Dairy waste effluent (DWE) was rich of cellulolytic and xylanolytic bacteria. ► Solid AD inoculated with DWE produced the highest methane yield at F/E ratio of 2. - Abstract: Effluents from three liquid anaerobic digesters, fed with municipal sewage sludge, food waste, or dairy waste, were evaluated as inocula and nitrogen sources for solid-state batch anaerobic digestion of corn stover in mesophilic reactors. Three feedstock-to-effluent (F/E) ratios (i.e., 2, 4, and 6) were tested for each effluent. At an F/E ratio of 2, the reactor inoculated by dairy waste effluent achieved the highest methane yield of 238.5 L/kgVS feed , while at an F/E ratio of 4, the reactor inoculated by food waste effluent achieved the highest methane yield of 199.6 L/kgVS feed . The microbial population and chemical composition of the three effluents were substantially different. Food waste effluent had the largest population of acetoclastic methanogens, while dairy waste effluent had the largest populations of cellulolytic and xylanolytic bacteria. Dairy waste also had the highest C/N ratio of 8.5 and the highest alkalinity of 19.3 g CaCO 3 /kg. The performance of solid-state batch anaerobic digestion reactors was closely related to the microbial status in the liquid anaerobic digestion effluents.

  14. Comparison of different liquid anaerobic digestion effluents as inocula and nitrogen sources for solid-state batch anaerobic digestion of corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Xu Fuqing; Shi Jian [Department of Food, Agricultural and Biological Engineering, Ohio State University, Ohio Agricultural Research and Development Center, 1680 Madison Ave., Wooster, OH 44691 (United States); Lv Wen; Yu Zhongtang [Department of Animal Sciences, Ohio State University, Columbus, OH 43210 (United States); Li Yebo, E-mail: li.851@osu.edu [Department of Food, Agricultural and Biological Engineering, Ohio State University, Ohio Agricultural Research and Development Center, 1680 Madison Ave., Wooster, OH 44691 (United States)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer Compared methane production of solid AD inoculated with different effluents. Black-Right-Pointing-Pointer Food waste effluent (FWE) had the largest population of acetoclastic methanogens. Black-Right-Pointing-Pointer Solid AD inoculated with FWE produced the highest methane yield at F/E ratio of 4. Black-Right-Pointing-Pointer Dairy waste effluent (DWE) was rich of cellulolytic and xylanolytic bacteria. Black-Right-Pointing-Pointer Solid AD inoculated with DWE produced the highest methane yield at F/E ratio of 2. - Abstract: Effluents from three liquid anaerobic digesters, fed with municipal sewage sludge, food waste, or dairy waste, were evaluated as inocula and nitrogen sources for solid-state batch anaerobic digestion of corn stover in mesophilic reactors. Three feedstock-to-effluent (F/E) ratios (i.e., 2, 4, and 6) were tested for each effluent. At an F/E ratio of 2, the reactor inoculated by dairy waste effluent achieved the highest methane yield of 238.5 L/kgVS{sub feed}, while at an F/E ratio of 4, the reactor inoculated by food waste effluent achieved the highest methane yield of 199.6 L/kgVS{sub feed}. The microbial population and chemical composition of the three effluents were substantially different. Food waste effluent had the largest population of acetoclastic methanogens, while dairy waste effluent had the largest populations of cellulolytic and xylanolytic bacteria. Dairy waste also had the highest C/N ratio of 8.5 and the highest alkalinity of 19.3 g CaCO{sub 3}/kg. The performance of solid-state batch anaerobic digestion reactors was closely related to the microbial status in the liquid anaerobic digestion effluents.

  15. Effects of Formic or Acetic Acid on the Storage Quality of Mixed Air-Dried Corn Stover and Cabbage Waste, and Microbial Community Analysis

    Directory of Open Access Journals (Sweden)

    Cong Wang

    2018-01-01

    Full Text Available A mixture of air-dried corn stover and cabbage waste was ensiled to preserve lignocellulosic biomass for use as biofuel. Furthermore, the effects of different fresh mass fractions (0.3 and 0.6 % of formic or acetic acid on the mixed silage quality were evaluated to guarantee its quality. The application of formic or acetic acid prior to mixing the silage led to higher water-soluble carbohydrate fractions than the negative control, indicating that both acids contributed to preservation of water-soluble carbohydrates during storage for 170 days. The dry matter content was also increased after storage from 90 to 170 days. It was found that the content of neutral and acid detergent fibre, cellulose and holocellulose (the sum of cellulose and hemicellulose in mixed silage treated with formic or acetic acid was significantly lower than that obtained in the negative control. The pH and the ratio of ammoniacal nitrogen to total nitrogen in mixed silage treated with acetic acid also significantly decreased. Furthermore, the addition of formic or acetic acid significantly weakened the fermentation intensity of lactic acid, depending on the ratio of lactic to acetic acid, as well as the ratio of lactic acid to total organic acids. The number of bacterial species and their relative abundance shifted during silage mixing, wherein microbial communities at phylum level mainly consisted of Proteobacteria and Firmicutes. The dominant bacteria were also observed to shift from Lactobacillus and Enterobacter in presilage biomass to Lactobacillus and Paralactobacillus. Specifically, Enterobacter disappeared after 130 days of storage. In conclusion, the addition of a low dose of acetic acid to fresh mass (0.3 % could effectively improve the fermentation quality and is conducive to the preservation of the organic components.

  16. Low-heat, mild alkaline pretreatment of switchgrass for anaerobic digestion.

    Science.gov (United States)

    Jin, Guang; Bierma, Tom; Walker, Paul M

    2014-01-01

    This study examines the effectiveness of alkaline pretreatment under mild heat conditions (100°C or 212°F) on the anaerobic co-digestion of switchgrass. The effects of alkaline concentration, types of alkaline, heating time and rinsing were evaluated. In addition to batch studies, continuous-feed studies were performed in triplicate to identify potential digester operational problems caused by switchgrass co-digestion while accounting for uncertainty due to digester variability. Few studies have examined anaerobic digestion of switchgrass or the effects of mild heating to enhance alkaline pretreatment prior to biomass digestion. Results indicate that pretreatment can significantly enhance digestion of coarse-ground (≤ 0.78 cm particle size) switchgrass. Energy conversion efficiency as high as 63% was observed, and was comparable or superior to fine-grinding as a pretreatment method. The optimal NaOH concentration was found to be 5.5% (wt/wt alkaline/biomass) with a 91.7% moisture level. No evidence of operational problems such as solids build-up, poor mixing, or floating materials were observed. These results suggest the use of waste heat from a generator could reduce the concentration of alkaline required to adequately pretreat lignocellulosic feedstock prior to anaerobic digestion.

  17. Hydrodynamic cavitation-assisted alkaline pretreatment as a new approach for sugarcane bagasse biorefineries.

    Science.gov (United States)

    Terán Hilares, Ruly; Dos Santos, Júlio César; Ahmed, Muhammad Ajaz; Jeon, Seok Hwan; da Silva, Silvio Silvério; Han, Jong-In

    2016-08-01

    Hydrodynamic cavitation (HC) was employed in order to improve the efficiency of alkaline pretreatment of sugarcane bagasse (SCB). Response surface methodology (RSM) was used to optimize pretreatment parameters: NaOH concentration (0.1-0.5M), solid/liquid ratio (S/L, 3-10%) and HC time (15-45min), in terms of glucan content, lignin removal and enzymatic digestibility. Under an optimal HC condition (0.48M of NaOH, 4.27% of S/L ratio and 44.48min), 52.1% of glucan content, 60.4% of lignin removal and 97.2% of enzymatic digestibility were achieved. Moreover, enzymatic hydrolysis of the pretreated SCB resulted in a yield 82% and 30% higher than the untreated and alkaline-treated controls, respectively. HC was found to be a potent and promising approach to pretreat lignocellulosic biomass. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Improving methane production from anaerobic digestion of Pennisetum Hybrid by alkaline pretreatment.

    Science.gov (United States)

    Kang, Xihui; Sun, Yongming; Li, Lianhua; Kong, Xiaoying; Yuan, Zhenhong

    2018-05-01

    Alkaline pretreatment with NaOH was used to improve methane yield from Pennisetum Hybrid. The pretreatments were carried out with different NaOH solutions (2-8% w/w) at three temperatures (35, 55 and 121 °C) for different periods of time (24, 24 and 1 h). All treated and untreated Pennisetum Hybrid were digested under mesophilic conditions (37 °C) to biogas, significant effects of the pretreatments on the yield of methane were observed. Results showed the modified Gompertz equation was reliable (determination coefficients (R 2 ) greater than 0.96) to describe the kinetic behavior of anaerobic digestion of Pennisetum Hybrid. The best result, obtained by the treatment at 35 °C 2% NaOH for 24 h, resulted in the methane yield of 301.7 mL/g VS, corresponding to 21.0% improvement in the methane yield. Compositional, SEM, XRD and FTIR analysis confirmed that lignin removal, structural modification and cellulose crystalline variation were responsible for the improvement. Copyright © 2018 Elsevier Ltd. All rights reserved.

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

    International Nuclear Information System (INIS)

    Nor Aishah Saidina Amin; Roslindawati Haron

    2010-01-01

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

  20. Bioethanol production from corn stover residues. Process design and Life Cycle Assessment; Bioetanolo da resuidui della lavorazione del mais: process design e analisi del ciclo di vita

    Energy Technology Data Exchange (ETDEWEB)

    De Bari, I; Dinnino, G; Braccio, G [Dipartimento Tecnologie per l' Energia, Fonti Rinnovabili e Risparmio Energetico, ENEA, Centro Ricerche Trisaia, Matera (Italy)

    2008-07-01

    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. [Italian] Questo rapporto illustra il bilancio di massa e di energia insieme alla valutazione del Ciclo di vita (LCA) per un processo industriale di produzione di bioetanolo da residui di mais costituito dalle principali tecnologie studiate

  1. Cost Effective Bioethanol via Acid Pretreatment of Corn Stover, Saccharification, and Conversion via a Novel Fermentation Organism: Cooperative Research and Development Final Report, CRADA Number: CRD-12-485

    Energy Technology Data Exchange (ETDEWEB)

    Dowe, N.

    2014-05-01

    This research program will convert acid pretreated corn stover to sugars at the National Renewable Energy Laboratory (NREL) and then transfer these sugars to Honda R&D and its partner the Green Earth Institute (GEI) for conversion to ethanol via a novel fermentation organism. In phase one, NREL will adapt its pretreatment and saccharification process to the unique attributes of this organism, and Honda R&D/GEI will increase the sugar conversion rate as well as the yield and titer of the resulting ethanol. In later phases, NREL, Honda R&D, and GEI will work together at NREL to optimize and scale-up to pilot-scale the Honda R&D/GEI bioethanol production process. The final stage will be to undertake a pilot-scale test at NREL of the optimized bioethanol conversion process.

  2. Corn

    OpenAIRE

    Sherwood, Brianne; Hawks, Amanda

    2011-01-01

    We have so much corn right now it's coming out of our ears (great pun, right?). And it's SO incredibly cheap! This is probably because the US produces 42% of the world's corn! Most of it is used for animal feed, but other uses include exporting to other countries, human food, seed, and industrial uses such as ethanol production. Because there is so much corn available here in the U.S. You can find it in a lot more foods than you think. It's in peanut butter, snack foods, soft drinks, multivit...

  3. Synergistic effect of alkaline pretreatment and Fe dosing on batch anaerobic digestion of maize straw

    International Nuclear Information System (INIS)

    Khatri, Shailendra; Wu, Shubiao; Kizito, Simon; Zhang, Wanqin; Li, Jiaxi; Dong, Renjie

    2015-01-01

    Highlights: • Synergistic effect of NaOH treatment and Fe dosage to maize straw was investigated. • Combining NaOH treatment and Fe dosing resulted in 57% and 56% higher biogas and methane yield respectively. • Combined treatment shortened the technical digestion time from 48 days to 7 days. • Methane content did not differ significantly among the straw treatments. - Abstract: The synergistic effect of alkaline pretreatment and Fe dosing on anaerobic digestion of maize straw was investigated using mesophilic batch reactors. Three straw treatments were investigated as follows: NaOH (4% and 6%) pretreatment, Fe dosage (50, 200, 1000 and 2000 mg/L), and combined NaOH pretreatment and Fe dosage. Compared to the control, NaOH pretreatment alone increased methane yield by 3.5% (313.3 mL CH_4/gVS) and 22.5% (370.9 mL CH_4/gVS) and shortened the technical digestion time (TDT) from 48 days to 19 days and 10 days in 4% NaOH and 6% NaOH pretreatment respectively. Moreover, Fe dosing (200–1000 mg/L) alone gave a methane yield higher (9.4%) than that obtained from 4% NaOH and 7.5% less than the methane yield from 6% NaOH pretreatment; however, the TDT was 10 days longer. Combining NaOH pretreatment and Fe dosage (200–1000 mg/L) significantly increased the methane yield even further to 21.8% (368.8 mL CH_4/gVS) and 56.2% (472.9 mL CH_4/gVS), and shortened TDT from 48 days to 13 days and 7 days in 4% NaOH and 6% NaOH pretreatment respectively. This synergistic effect may be attributed to the fact that the alkaline treatment improved accessibility of the biodegradable fraction of the straw while Fe contributed to increased microbial enzyme activity.

  4. Anaerobic co-digestion of microalgal biomass and wheat straw with and without thermo-alkaline pretreatment.

    Science.gov (United States)

    Solé-Bundó, Maria; Eskicioglu, Cigdem; Garfí, Marianna; Carrère, Hélène; Ferrer, Ivet

    2017-08-01

    This study aimed at analyzing the anaerobic co-digestion of microalgal biomass grown in wastewater and wheat straw. To this end, Biochemical Methane Potential (BMP) tests were carried out testing different substrate proportions (20-80, 50-50 and 80-20%, on a volatile solid basis). In order to improve their biodegradability, the co-digestion of both substrates was also evaluated after applying a thermo-alkaline pretreatment (10% CaO at 75°C for 24h). The highest synergies in degradation rates were observed by adding at least 50% of wheat straw. Therefore, the co-digestion of 50% microalgae - 50% wheat straw was investigated in mesophilic lab-scale reactors. The results showed that the methane yield was increased by 77% with the co-digestion as compared to microalgae mono-digestion, while the pretreatment only increased the methane yield by 15% compared to the untreated mixture. Thus, the anaerobic co-digestion of microalgae and wheat straw was successful even without applying a thermo-alkaline pretreatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Marykate O'Brien | NREL

    Science.gov (United States)

    Pretreatment of Corn Stover," ACS Sustainable Chemistry and Engineering (2016) "Acidolysis of α-O-4 Chemistry and Engineering (2015) "Alkaline pretreatment of switchgrass," ACS Sustainable Chemistry stream characterization," ACS Sustainable Chemistry and Engineering (2014) "Lignin

  6. Stover removal effects on seasonal soil water availability under full and deficit irrigation

    Science.gov (United States)

    Removing corn (Zea mays L.) stover for livestock feed or bioenergy feedstock may impact water availability in the soil profile to support crop growth. The role of stover in affecting soil profile water availability will depend on annual rainfall inputs as well as irrigation level. To assess how res...

  7. Effectiveness of Alkaline Pretreatment and Acetic Acid Hydrolysis on the Characteristics of Collagen from Fish Skin of Snakehead

    Directory of Open Access Journals (Sweden)

    Wulandari

    2015-12-01

    Full Text Available Fish skin is one of marine byproducts potential for alternative source of collagen. This study investigated the effectiveness of alkaline and acetic acid pretreatment on the characteristics of collagen from skin snakehead fish. The concentrations of alkaline pretreatment were 0.05; 0.1; 0.15 and 0.2 M for 2, 4, 6, 8, 10 and 12 hours, acetic acid concentrations were 0.05 M, 0.1 M, 0.15 M and 0.2 M for 1 and 2 hours. The experimental design used for alkaline and acetic acid pretreatment was factorial completely randomized design. The result showed that the concentration of alkaline 0.05 M for 6 hours have significant effect on the elimination of non-collagen protein (p<0.05, whereas for the optimum acetic acid at a concentration 0.1 M for 2 hours significantly different on solubility and swelling. Extraction yields of collagen was 16%, with characteristics of whiteness 66.67%, protein content 96.21%, viscosity 10 cP, Tmax 159.9oC and glass transition temperature 78.55oC. The dominant amino acid composition were glycine (27.11%, proline (13.87% and alanine (12.58%. Functional groups collagen from skin snakehead fish has β-sheet structure which is a characteristic of collagen.

  8. Effectiveness of Alkaline Pretreatment and Acetic Acid Hydrolysis on the Characteristics of Collagen from Fish Skin of Snakehead

    Directory of Open Access Journals (Sweden)

    Wulandari Wulandari

    2015-12-01

    Full Text Available Fish skin is one of marine byproducts potential for alternative source of collagen. This studyinvestigated the effectiveness of alkaline and acetic acid pretreatment on the characteristics ofcollagen from skin snakehead fish. The concentrations of alkaline pretreatment were 0.05; 0.1; 0.15and 0.2 M for 2, 4, 6, 8, 10 and 12 hours, acetic acid concentrations were 0.05 M, 0.1 M, 0.15 M and0.2 M for 1 and 2 hours. The experimental design used for alkaline and acetic acid pretreatmentwas factorial completely randomized design. The result showed that the concentration of alkaline0.05 M for 6 hours have significant effect on the elimination of non-collagen protein (p<0.05,whereas for the optimum acetic acid at a concentration 0.1 M for 2 hours significantly differenton solubility and swelling. Extraction yields of collagen was 16%, with characteristics of whiteness66.67%, protein content 96.21%, viscosity 10 cP, Tmax 159.9oC and glass transition temperature78.55oC. The dominant amino acid composition were glycine (27.11%, proline (13.87% andalanine (12.58%. Functional groups collagen from skin snakehead fish has β-sheet structurewhich is a characteristic of collagen.

  9. Phenology and biomass production of adapted and non-adapted tropical corn populations in Central Iowa

    Science.gov (United States)

    Biofuel production in the Midwestern United States has largely focused on corn (Zea mays L.) grain for ethanol production and more recently, corn stover for lignocellulosic ethanol. As an alternative to conventional corn, tropical corn populations have been evaluated. Tropical corn is the term used ...

  10. Asparagus stem as a new lignocellulosic biomass feedstock for anaerobic digestion: increasing hydrolysis rate, methane production and biodegradability by alkaline pretreatment.

    Science.gov (United States)

    Chen, Xiaohua; Gu, Yu; Zhou, Xuefei; Zhang, Yalei

    2014-07-01

    Recently, anaerobic digestion of lignocellulosic biomass for methane production has attracted considerable attention. However, there is little information regarding methane production from asparagus stem, a typical lignocellulosic biomass, by anaerobic digestion. In this study, alkaline pretreatment of asparagus stem was investigated for its ability to increase hydrolysis rate and methane production and to improve biodegradability (BD). The hydrolysis rate increased with increasing NaOH dose, due to higher removal rates of lignin and hemicelluloses. However, the optimal NaOH dose was 6% (w/w) according to the specific methane production (SMP). Under this condition, the SMP and the technical digestion time of the NaOH-treated asparagus stem were 242.3 mL/g VS and 18 days, which were 38.4% higher and 51.4% shorter than those of the untreated sample, respectively. The BD was improved from 40.1% to 55.4%. These results indicate that alkaline pretreatment could be an efficient method for increasing methane production from asparagus stem. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Comparison of corn and switchgrass on marginal soils for bioenergy

    Energy Technology Data Exchange (ETDEWEB)

    Varvel, G.E.; Vogel, K.P.; Mitchell, R.B. [USDA-ARS, 344 Keim Hall, University of Nebraska-Lincoln, P.O. Box 830937, Lincoln, NE 68583-0937 (United States); Follett, R.F. [USDA-ARS, Room S-100, 2150 Centre Avenue Building D, Ft. Collins, CO 80526-8119 (United States); Kimble, J.M. [USDA-NRCS, National Soil Survey Center, 100 Centennial Mall North, Lincoln, NE 68508-3866 (United States)

    2008-01-15

    Crop residues such as corn (Zea mays L.) stover are viewed as an abundant and inexpensive source of biomass that can be removed from fields to produce bioenergy. Assumptions include that with minimum or no-tillage farming methods, there will be no deleterious production or environmental effects. A long-term field study was established in eastern Nebraska, USA, to compare the switchgrass managed as a biomass energy crop versus no-till corn on a non-irrigated site, marginal for row-crop production, in the western Corn Belt. Our objective in this paper is to report on corn stover removal effects on corn grain yields and potential ethanol production in both cropping systems. Corn, under no-till management, and switchgrass were grown at three N fertilizer levels. In the first 5 years (2001-2005), removal of half the available stover significantly reduced corn yields. During that same time period, the potential ethanol yield for switchgrass was equal to or greater than the potential total ethanol yield of corn grain and harvested stover fertilized at the same optimum N rate. The effect of crop residue removal on crop productivity needs to be investigated in other agro-ecosystems and the potential use of dedicated perennial biomass energy crops should remain a viable renewable energy option on non-irrigated marginal croplands. (author)

  12. Thermo-alkaline pretreatment of waste activated sludge at low-temperatures: effects on sludge disintegration, methane production, and methanogen community structure.

    Science.gov (United States)

    Kim, Jaai; Yu, Youngseob; Lee, Changsoo

    2013-09-01

    Low-temperature thermo-alkaline pretreatment of waste activated sludge (WAS) was studied, within the region of 0-0.2 M NaOH and 60-90°C, for the effects of NaOH concentration and temperature on sludge degradability in anaerobic digestion (AD). Significant disintegration of sludge solids (up to 75.6%) and an increase in methane production (up to 70.6%) were observed in the pretreatment trials. Two quadratic models were successfully generated by response surface analysis (R(2)>0.9, pdisintegration (SD) and methane production (MP) respond to changes in the pretreatment conditions. The maximum responses of SD (77.8%) and MP (73.9% increase over the control) were shown at [0.16 M NaOH, 90°C] and [0.10 M NaOH, 73.7°C], respectively. NaOH addition showed a significant influence on the evolution of methanogen community structure during AD, whereas temperature did not. Aceticlastic Methanosaeta and Methanosarcina speceies were likely the major methanogens. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Effect of alkaline pretreatment on mesophilic and thermophilic anaerobic digestion of a submerged macrophyte: Inhibition and recovery against dissolved lignin during semi-continuous operation.

    Science.gov (United States)

    Koyama, Mitsuhiko; Watanabe, Keiko; Kurosawa, Norio; Ishikawa, Kanako; Ban, Syuhei; Toda, Tatsuki

    2017-08-01

    The long-term effect of alkaline pretreatment on semi-continuous anaerobic digestion (AD) of the lignin-rich submerged macrophyte Potamogeton maackianus was investigated using mesophilic and thermophilic conditions. In pretreated reactors, dissolved lignin accumulated to high levels. CH 4 production under the pretreated condition was higher than that of the untreated condition, but decreased from Days 22 (mesophilic) and 42 (thermophilic). However, CH 4 production subsequently recovered, although dissolved lignin accumulated. Further, the change in the microbial community was observed between conditions. These results suggest that dissolved lignin temporarily inhibited AD, although acclimatization to dissolved lignin occurred during long-term operation. During the steady state period, mesophilic conditions achieved a 42% increase in the CH 4 yield using pretreatment, while thermophilic conditions yielded an 8% increment. Because volatile fatty acids accumulated even after acclimatization during the thermophilic pretreated condition and was discharged with the effluent, improvement of the methanogenic step would enable enhanced CH 4 recovery. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Impact of acid and alkaline pretreatments on the molecular network of wheat gluten and on the mechanical properties of compression-molded glassy wheat gluten bioplastics.

    Science.gov (United States)

    Jansens, Koen J A; Lagrain, Bert; Brijs, Kristof; Goderis, Bart; Smet, Mario; Delcour, Jan A

    2013-10-02

    Wheat gluten can be converted into rigid biobased materials by high-temperature compression molding at low moisture contents. During molding, a cross-linked protein network is formed. This study investigated the effect of mixing gluten with acid/alkali in 70% ethanol at ambient temperature for 16 h followed by ethanol removal, freeze-drying, and compression molding at 130 and 150 °C on network formation and on types of cross-links formed. Alkaline pretreatment (0-100 mmol/L sodium hydroxide or 25 mmol/L potassium hydroxide) strongly affected gluten cross-linking, whereas acid pretreatment (0-25 mmol/L sulfuric acid or 25 mmol/L hydrochloric acid) had limited effect on the gluten network. Molded alkaline-treated gluten showed enhanced cross-linking but also degradation when treated with high alkali concentrations, whereas acid treatment reduced gluten cross-linking. β-Elimination of cystine and lanthionine formation occurred more pronouncedly at higher alkali concentrations. In contrast, formation of disulfide and nondisulfide cross-links during molding was hindered in acid-pretreated gluten. Bioplastic strength was higher for alkali than for acid-pretreated samples, whereas the flexural modulus was only slightly affected by either alkaline or acid pretreatment. Apparently, the ratio of disulfide to nondisulfide cross-links did not affect the mechanical properties of rigid gluten materials.

  15. Implications of Using Corn Stalks as a Biofuel Source: A Joint ARS and DOE Project

    Science.gov (United States)

    Wilhelm, W. W.; Cushman, J.

    2003-12-01

    Corn stover is a readily source of biomass for cellulosic ethanol production, and may provide additional income for growers. Published research shows that residue removal changes the rate of soil physical, chemical, and biological processes, and in turn, crop growth. Building a sustainable cellulosic ethanol industry based on corn residue requires residue management practices that do not reduce long-term productivity. To develop such systems, impacts of stover removal on the soil and subsequent crops must be quantified. The ARS/DOE Biofuel Project is the cooperative endeavor among scientists from six western Corn Belt US Dept. of Agriculture, Agricultural Research Service (ARS) locations and US Dept. of Energy. The objectives of the project are to determine the influence of stover removal on crop productivity, soil aggregation, quality, carbon content, and seasonal energy balance, and carbon sequestration. When residue is removed soil temperatures fluctuate more and soil water evaporation is greater. Residue removal reduces the amount of soil organic carbon (SOC), but the degree of reduction is highly dependent on degree of tillage, quantity of stover removed, and frequency of stover removal. Of the three cultural factors (stover removal, tillage, and N fertilization) tillage had the greatest effect on amount of corn-derived SOC. No tillage tends to increase the fraction of aggregates in the 2.00 to 0.25 mm size range at all removal rates. Stover harvest reduces corn-derived SOC by 35% compared to retaining stover on the soil averaged over all tillage systems. Corn stover yield has not differed across stover removal treatments in these studies. In the irrigated study, grain yield increased with stover removal. In the rain-fed studies, grain yield has not differed among residue management treatments. Incorporating the biomass ethanol fermentation by-product into a soil with low SOC showed a positive relationship between the amount of lignin added and the subsequent

  16. 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

  17. Reducing life cycle greenhouse gas emissions of corn ethanol by integrating biomass to produce heat and power at ethanol plants

    International Nuclear Information System (INIS)

    Kaliyan, Nalladurai; Morey, R. Vance; Tiffany, Douglas G.

    2011-01-01

    A life-cycle assessment (LCA) of corn ethanol was conducted to determine the reduction in the life-cycle greenhouse gas (GHG) emissions for corn ethanol compared to gasoline by integrating biomass fuels to replace fossil fuels (natural gas and grid electricity) in a U.S. Midwest dry-grind corn ethanol plant producing 0.19 hm 3 y -1 of denatured ethanol. The biomass fuels studied are corn stover and ethanol co-products [dried distillers grains with solubles (DDGS), and syrup (solubles portion of DDGS)]. The biomass conversion technologies/systems considered are process heat (PH) only systems, combined heat and power (CHP) systems, and biomass integrated gasification combined cycle (BIGCC) systems. The life-cycle GHG emission reduction for corn ethanol compared to gasoline is 38.9% for PH with natural gas, 57.7% for PH with corn stover, 79.1% for CHP with corn stover, 78.2% for IGCC with natural gas, 119.0% for BIGCC with corn stover, and 111.4% for BIGCC with syrup and stover. These GHG emission estimates do not include indirect land use change effects. GHG emission reductions for CHP, IGCC, and BIGCC include power sent to the grid which replaces electricity from coal. BIGCC results in greater reductions in GHG emissions than IGCC with natural gas because biomass is substituted for fossil fuels. In addition, underground sequestration of CO 2 gas from the ethanol plant's fermentation tank could further reduce the life-cycle GHG emission for corn ethanol by 32% compared to gasoline.

  18. Aspen Plus simulation of biomass integrated gasification combined cycle systems at corn ethanol plants

    International Nuclear Information System (INIS)

    Zheng, Huixiao; Kaliyan, Nalladurai; Morey, R. Vance

    2013-01-01

    Biomass integrated gasification combined cycle (BIGCC) systems and natural gas combined cycle (NGCC) systems are employed to provide heat and electricity to a 0.19 hm 3 y −1 (50 million gallon per year) corn ethanol plant using different fuels (syrup and corn stover, corn stover alone, and natural gas). Aspen Plus simulations of BIGCC/NGCC systems are performed to study effects of different fuels, gas turbine compression pressure, dryers (steam tube or superheated steam) for biomass fuels and ethanol co-products, and steam tube dryer exhaust treatment methods. The goal is to maximize electricity generation while meeting process heat needs of the plant. At fuel input rates of 110 MW, BIGCC systems with steam tube dryers provide 20–25 MW of power to the grid with system thermal efficiencies (net power generated plus process heat rate divided by fuel input rate) of 69–74%. NGCC systems with steam tube dryers provide 26–30 MW of power to the grid with system thermal efficiencies of 74–78%. BIGCC systems with superheated steam dryers provide 20–22 MW of power to the grid with system thermal efficiencies of 53–56%. The life-cycle greenhouse gas (GHG) emission reduction for conventional corn ethanol compared to gasoline is 39% for process heat with natural gas (grid electricity), 117% for BIGCC with syrup and corn stover fuel, 124% for BIGCC with corn stover fuel, and 93% for NGCC with natural gas fuel. These GHG emission estimates do not include indirect land use change effects. -- Highlights: •BIGCC and natural gas combined cycle systems at corn ethanol plants are simulated. •The best performance results in 25–30 MW power to grid. •The best performance results in 74–78% system thermal efficiencies. •GHG reduction for corn ethanol with BIGCC systems compared to gasoline is over 100%

  19. Energy and greenhouse gas profiles of polyhydroxybutyrates derived from corn grain: a life cycle perspective.

    Science.gov (United States)

    Kim, Seungdo; Dale, Bruce E

    2008-10-15

    Polyhydroxybutyrates (PHB) are well-known biopolymers derived from sugars orvegetable oils. Cradle-to-gate environmental performance of PHB derived from corn grain is evaluated through life cycle assessment (LCA), particularly nonrenewable energy consumption and greenhouse gas emissions. Site-specific process information on the corn wet milling and PHB fermentation and recovery processes was obtained from Telles. Most of energy used in the corn wet milling and PHB fermentation and recovery processes is generated in a cogeneration power plant in which corn stover, assumed to be representative of a variety of biomass sources that could be used, is burned to generate electricity and steam. County level agricultural information is used in estimating the environmental burdens associated with both corn grain and corn stover production. Results show that PHB derived from corn grain offers environmental advantages over petroleum-derived polymers in terms of nonrenewable energy consumption and greenhouse gas emissions. Furthermore, PHB provides greenhouse gas credits, and thus PHB use reduces greenhouse gas emissions compared to petroleum-derived polymers. Corn cultivation is one of the environmentally sensitive areas in the PHB production system. More sustainable practices in corn cultivation (e.g., using no-tillage and winter cover crops) could reduce the environmental impacts of PHB by up to 72%.

  20. Legumes and forage species sole or intercropped with corn in soybean-corn succession in midwestern Brazil

    Directory of Open Access Journals (Sweden)

    Gessí Ceccon

    2013-02-01

    Full Text Available The feasibility of no-tillage in the Cerrado (Savanna-like vegetation of Brazil depends on the production of sufficient above-ground crop residue, which can be increased by corn-forage intercropping. This study evaluated how above-ground crop residue production and yields of soybean and late-season corn in a soybean-corn rotation were influenced by the following crops in the year before soybean: corn (Zea mays L. intercropped with Brachiaria (Urochloa brizantha cv. Marandu, B. decumbens cv. Basilisk, B. ruziziensis, cv. comum., Panicummaximum cv. Tanzânia, sunn hemp (Crotalaria juncea L., pigeon pea [Cajanus cajan (L. Millsp]; sole corn, forage sorghum [Sorghum bicolor (L. Moench (cv. Santa Elisa], and ruzi grass. In March 2005, corn and forage species were planted in alternate rows spaced 0.90 m apart, and sole forage species were planted in rows spaced 0.45 m apart. In October 2005, the forages were killed with glyphosate and soybean was planted. After the soybean harvest in March 2006, sole late-season corn was planted in the entire experimental area. Corn grain and stover yields were unaffected by intercropping. Above-ground crop residue was greater when corn was intercropped with Tanzania grass (10.7 Mg ha-1, Marandu (10.1 Mg ha-1, and Ruzi Grass (9.8 Mg ha-1 than when corn was not intercropped (4.0 Mg ha-1. The intercropped treatments increased the percentage of soil surface covered with crop residue. Soybean and corn grain yields were higher after sole ruzi grass and intercropped ruzi grass than after other crops. The intercropping corn with Brachiaria spp. and corn with Panicum spp. increases above-ground crop residue production and maintains nutrients in the soil without reducing late-season corn yield and the viability of no-till in the midwestern region of Brazil.

  1. Enzymatic Hydrolysis of Alkaline Pretreated Coconut Coir

    Directory of Open Access Journals (Sweden)

    Akbarningrum Fatmawati

    2013-06-01

    Full Text Available The purpose of this research is to study the effect of concentration and temperature on the cellulose and lignin content, and the reducing sugars produced in the enzymatic hydrolysis of coconut coir. In this research, the coconut coir is pretreated using 3%, 7%, and 11% NaOH solution at 60oC, 80oC, and 100oC. The pretreated coir were assayed by measuring the amount of cellulose and lignin and then hydrolysed using Celluclast and Novozyme 188 under various temperature (30oC, 40oC, 50oC and pH (3, 4, 5. The hydrolysis results were assayed for the reducing sugar content. The results showed that the alkaline delignification was effective to reduce lignin and to increase the cellulose content of the coir. The best delignification condition was observed at 11% NaOH solution and 100oC which removed 14,53% of lignin and increased the cellulose content up to 50,23%. The best condition of the enzymatic hydrolysis was obtained at 50oC and pH 4 which produced 7,57 gr/L reducing sugar. © 2013 BCREC UNDIP. All rights reservedReceived: 2nd October 2012; Revised: 31st January 2013; Accepted: 6th February 2013[How to Cite: Fatmawati, A., Agustriyanto, R., Liasari, Y. (2013. Enzymatic Hydrolysis of Alkaline Pre-treated Coconut Coir. Bulletin of Chemical Reaction Engineering & Catalysis, 8 (1: 34-39 (doi:10.9767/bcrec.8.1.4048.34-39[Permalink/DOI: http://dx.doi.org/10.9767/bcrec.8.1.4048.34-39] | View in  |

  2. Cover crop root, shoot, and rhizodeposit contributions to soil carbon in a no- till corn bioenergy cropping system

    Science.gov (United States)

    Austin, E.; Grandy, S.; Wickings, K.; McDaniel, M. D.; Robertson, P.

    2016-12-01

    Crop residues are potential biofuel feedstocks, but residue removal may result in reduced soil carbon (C). The inclusion of a cover crop in a corn bioenergy system could provide additional biomass and as well as help to mitigate the negative effects of residue removal by adding belowground C to stable soil C pools. In a no-till continuous corn bioenergy system in the northern portion of the US corn belt, we used 13CO2 pulse labeling to trace C in a winter rye (secale cereale) cover crop into different soil C pools for two years following rye termination. Corn stover contributed 66 (another 163 was in harvested corn stover), corn roots 57, rye shoot 61, rye roots 59, and rye rhizodeposits 27 g C m-2 to soil C. Five months following cover crop termination, belowground cover crop inputs were three times more likely to remain in soil C pools and much of the root-derived C was in mineral- associated soil fractions. Our results underscore the importance of cover crop roots vs. shoots as a source of soil C. Belowground C inputs from winter cover crops could substantially offset short term stover removal in this system.

  3. Integrating livestock manure with a corn-soybean bioenergy cropping system improves short-term carbon sequestration rates and net global warming potential

    Energy Technology Data Exchange (ETDEWEB)

    Thelen, K.D.; Fronning, B.E.; Kravchenko, A.; Min, D.H.; Robertson, G.P. [Michigan State University, East Lansing, MI 48824 (United States)

    2010-07-15

    Carbon cycling and the global warming potential (GWP) of bioenergy cropping systems with complete biomass removal are of agronomic and environmental concern. Corn growers who plan to remove corn stover as a feedstock for the emerging cellulosic ethanol industry will benefit from carbon amendments such as manure and compost, to replace carbon removed with the corn stover. The objective of this research was to determine the effect of beef cattle feedlot manure and composted dairy manure on short-term carbon sequestration rates and net global warming potential (GWP) in a corn-soybean rotation with complete corn-stover removal. Field experiments consisting of a corn-soybean rotation with whole-plant corn harvest, were conducted near East Lansing, MI over a three-year period beginning in 2002. Compost and manure amendments raised soil carbon (C) at a level sufficient to overcome the C debt associated with manure production, manure collection and storage, land application, and post-application field emissions. The net GWP in carbon dioxide equivalents for the manure and compost amended cropping systems was -934 and -784 g m{sup -2} y{sup -1}, respectively, compared to 52 g m{sup -2} y{sup -1} for the non-manure amended synthetic fertilizer check. This work further substantiates the environmental benefits associated with renewable fuels and demonstrates that with proper management, the integration of livestock manures in biofuel cropping systems can enhance greenhouse gas (GHG) remediation. (author)

  4. Integrating livestock manure with a corn-soybean bioenergy cropping system improves short-term carbon sequestration rates and net global warming potential

    International Nuclear Information System (INIS)

    Thelen, K.D.; Fronning, B.E.; Kravchenko, A.; Min, D.H.; Robertson, G.P.

    2010-01-01

    Carbon cycling and the global warming potential (GWP) of bioenergy cropping systems with complete biomass removal are of agronomic and environmental concern. Corn growers who plan to remove corn stover as a feedstock for the emerging cellulosic ethanol industry will benefit from carbon amendments such as manure and compost, to replace carbon removed with the corn stover. The objective of this research was to determine the effect of beef cattle feedlot manure and composted dairy manure on short-term carbon sequestration rates and net global warming potential (GWP) in a corn-soybean rotation with complete corn-stover removal. Field experiments consisting of a corn-soybean rotation with whole-plant corn harvest, were conducted near East Lansing, MI over a three-year period beginning in 2002. Compost and manure amendments raised soil carbon (C) at a level sufficient to overcome the C debt associated with manure production, manure collection and storage, land application, and post-application field emissions. The net GWP in carbon dioxide equivalents for the manure and compost amended cropping systems was -934 and -784 g m -2 y -1 , respectively, compared to 52 g m -2 y -1 for the non-manure amended synthetic fertilizer check. This work further substantiates the environmental benefits associated with renewable fuels and demonstrates that with proper management, the integration of livestock manures in biofuel cropping systems can enhance greenhouse gas (GHG) remediation.

  5. Corn Earworm

    OpenAIRE

    Alston, Diane G.; Olsen, Shawn; Barnhill, James

    2011-01-01

    In Utah, there are typically three generations of corn earworm (CEW) each year. The first generation of adults either come from overwintering pupae (southern and central Utah), or migrate into northern Utah. The adult moth is tannish brown with a 1 1/2 inch wingspan. The front wings are marked with a distinct dark spot in the center and darker bands near the outer margins. The hind wings are lighter tan, with a dark band along the outer margins. The male moths have green eyes. Moth flight occ...

  6. Influence of spatially dependent, modeled soil carbon emission factors on life-cycle greenhouse gas emissions of corn and cellulosic ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Zhangcai [Energy Systems Division, Argonne National Laboratory, 9700 South Cass Avenue Argonne IL 60439 USA; Dunn, Jennifer B. [Energy Systems Division, Argonne National Laboratory, 9700 South Cass Avenue Argonne IL 60439 USA; Kwon, Hoyoung [Environment and Production Technology Division, International Food Policy Research Institute, 2033 K St. NW Washington DC 20006 USA; Mueller, Steffen [Energy Resources Center, University of Illinois at Chicago, 1309 South Halsted Street Chicago IL 60607 USA; Wander, Michelle M. [Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, 1102 South Goodwin Avenue Urbana IL 61801 USA

    2016-03-03

    Converting land to biofuel feedstock production incurs changes in soil organic carbon (SOC) that can influence biofuel life-cycle greenhouse gas (GHG) emissions. Estimates of these land use change (LUC) and life-cycle GHG emissions affect biofuels’ attractiveness and eligibility under a number of renewable fuel policies in the U.S. and abroad. Modeling was used to refine the spatial resolution and depth-extent of domestic estimates of SOC change for land (cropland, cropland pasture, grasslands, and forests) conversion scenarios to biofuel crops (corn, corn stover, switchgrass, Miscanthus, poplar, and willow). In most regions, conversions from cropland and cropland pasture to biofuel crops led to neutral or small levels of SOC sequestration, while conversion of grassland and forest generally caused net SOC loss. Results of SOC change were incorporated into the Greenhouse Gases, Regulated Emissions, and Energy use in Transportation (GREET) model to assess their influence on life-cycle GHG emissions for the biofuels considered. Total LUC GHG emissions (g CO2eq MJ-1) were 2.1–9.3 for corn, -0.7 for corn stover, -3.4–12.9 for switchgrass, and -20.1–-6.2 for Miscanthus; these varied with SOC modeling assumptions applied. Extending soil depth from 30 to 100cm affected spatially-explicit SOC change and overall LUC GHG emissions; however the influence on LUC GHG emissions estimates were less significant in corn and corn stover than cellulosic feedstocks. Total life-cycle GHG emissions (g CO2eq MJ-1, 100cm) were estimated to be 59–66 for corn ethanol, 14 for stover ethanol, 18-26 for switchgrass ethanol, and -0.6–-7 for Miscanthus ethanol.

  7. Stochastic Corn Yield Response Functions to Nitrogen for Corn after Corn, Corn after Cotton, and Corn after Soybeans

    OpenAIRE

    Boyer, Christopher N.; Larson, James A.; Roberts, Roland K.; McClure, Angela T.; Tyler, Donald D.; Zhou, Vivian

    2013-01-01

    Deterministic and stochastic yield response plateau functions were estimated to determine the expected profit-maximizing nitrogen rates, yields, and net returns for corn grown after corn, cotton, and soybeans. The stochastic response functions were more appropriate than their deterministic counterparts, and the linear response stochastic plateau described the data the best. The profit-maximizing nitrogen rates were similar for corn after corn, cotton, and soybeans, but relative to corn after ...

  8. Baby corn, green corn, and dry corn yield of corn cultivars

    OpenAIRE

    Castro,Renato S; Silva,Paulo Sérgio L; Cardoso,Milton J

    2013-01-01

    In corn, when the first female inflorescence is removed, the plant often produces new female inflorescences. This allows the first ear to be harvested as baby corn (BC) and the second as green corn (GC) or dry corn (DC), that is, mature corn. The flexibility provided by a variety of harvested products allows the grower to compete with better conditions in the markets. We evaluated BC, GC, and DC yields in corn cultivars AG 1051, AG 2060, and BRS 2020, after the first ear was harvested as BC. ...

  9. Our Mother Corn.

    Science.gov (United States)

    Mathers, Sherry; And Others

    Developed to provide an understanding of the magnitude of the role of corn, referred to as Mother Corn in the cultures of the Seneca, Pawnee, and Hopi tribes, the student text provides information on the tribes' basic lifestyles and the way they grew and used corn in three different parts of the United States. The section on the origin of corn…

  10. Corn stover for advanced biofuels – Soil “Lorax” perspectives

    Science.gov (United States)

    Crop residues serve numerous agroecosystem function. Harvesting these materials must be done in a manner that protects the soil. Soil is the thin layer that stand be us and starvation. Strategies to protect the soil resource to balance current and future societal needs will be discussed....

  11. A novel optimization approach to estimating kinetic parameters of the enzymatic hydrolysis of corn stover

    Directory of Open Access Journals (Sweden)

    Fenglei Qi

    2016-01-01

    Full Text Available Enzymatic hydrolysis is an integral step in the conversion of lignocellulosic biomass to ethanol. The conversion of cellulose to fermentable sugars in the presence of inhibitors is a complex kinetic problem. In this study, we describe a novel approach to estimating the kinetic parameters underlying this process. This study employs experimental data measuring substrate and enzyme loadings, sugar and acid inhibitions for the production of glucose. Multiple objectives to minimize the difference between model predictions and experimental observations are developed and optimized by adopting multi-objective particle swarm optimization method. Model reliability is assessed by exploring likelihood profile in each parameter space. Compared to previous studies, this approach improved the prediction of sugar yields by reducing the mean squared errors by 34% for glucose and 2.7% for cellobiose, suggesting improved agreement between model predictions and the experimental data. Furthermore, kinetic parameters such as K2IG2, K1IG, K2IG, K1IA, and K3IA are identified as contributors to the model non-identifiability and wide parameter confidence intervals. Model reliability analysis indicates possible ways to reduce model non-identifiability and tighten parameter confidence intervals. These results could help improve the design of lignocellulosic biorefineries by providing higher fidelity predictions of fermentable sugars under inhibitory conditions.

  12. Proximate and Ultimate Compositional Changes in Corn Stover during Torrefaction using Thermogravimetric Analyzer and Microwaves

    Energy Technology Data Exchange (ETDEWEB)

    Jaya Shankar Tumuluru

    2012-07-01

    Abstract The world is currently aiming to reduce the dependence on fossil fuels and to achieve a sustainable renewable supply. Renewable energies represent a diversity of energy sources that can help to maintain the equilibrium of different ecosystems. Among the various sources of renewable energy, biomass is considered carbon neutral because the carbon dioxide released during its use is already part of the carbon cycle. Increasing the use of biomass for energy can help to reduce the negative CO2 impact on the environment and help meet the targets established in the Kyoto Protocol. Energy from biomass can be produced from different processes, including thermochemical (direct combustion, gasification, and pyrolysis), biological (anaerobic digestion, fermentation), or chemical (esterification) technologies. There are lot challenges in using biomass for energy applications. To name few low bulk density, high moisture content, irregular size and shape, hydrophilic nature and low calorific value. In commercial scale operation large quantities of biomass are needed and this will create problems associated with storage and transportation. Furthermore, grinding raw biomass with high moisture content is very challenging as there are no specific equipments and can increase the costs and in some cases it becomes highly impossible. All of these drawbacks led to development of some pretreatment techniques to make biomass more suitable for fuel applications. One of the promising techniques is torrefaction. Torrefaction is heating the biomass in an inert environment or reduced environment. During torrefaction biomass losses moisture, becomes more brittle and with increased energy density values. There are different techniques used for torrefaction of biomass. Fixed bed, bubbling sand bed and moving bed are the most common ones used. The use of microwaves for torrefaction purposes has not been explored. In the present study we looked into the torrefaction of biomass using the regular and microwaves and their effect on proximate and ultimate composition. Studies indicated that microwave torrefaction is a good way to torrefy the biomass in short periods of time. A maximum calorific value of 21 MJ/kg is achievable at 6 min residence time compared to 15 min using the dry torrefaction technique. Increasing the residence time increased the carbon content where a maximum carbon content of 52.20 % was achievable at lower residence time. The loss of volatiles is comparatively lower compared to dry torrefaction technique. Moisture content of microwave torrefied samples was in between 2-2.5 % (w.b).

  13. Techno-economic analysis of corn stover fungal fermentation to ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Pimphan; Tews, Iva J.; Magnuson, Jon K.; Karagiosis, Sue A.; Jones, Susanne B.

    2013-11-01

    This techno-economic analysis assesses the process economics of ethanol production from lignocellulosic feedstock by fungi in order to identify promising opportunities and the research needed to achieve them. Based on literature derived data, four different ethanologen strains are considered in this study: native and recombinant Saccharomyces cerevisiae, the natural pentose-fermenting yeast, Pichia stipitis and the filamentous fungus Fusarium oxysporum. Organism performance and technology readiness are split into three groups: near-term (<5 years), mid-term (5-10 years) and long-term (>10 years) process deployment. Processes classified as near-term could reasonably be developed in this shorter time frame, as suggested by recent literature. Mid-term technology process models are based on lab-scale experimental data, and yields near the theoretical limit are used to estimate long-term technology goals. Further research and economic evaluation on the integrated production of chemicals and fuels in biorefineries are recommended.

  14. Techno-economic analysis of corn stover fungal fermentation to ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Pimphan A.; Tews, Iva J.; Magnuson, Jon K.; Karagiosis, Sue A.; Jones, Susanne B.

    2013-11-01

    This techno-economic analysis assesses the process economics of ethanol production from lignocellulosic feedstock by fungi to identify promising opportunities, and the research needed to achieve them. Based on literature derived data, four different ethanologen strains are considered in this study: native and recombinant Saccharomyces cerevisiae, the natural pentose-fermenting yeast, Pichia stipitis and the filamentous fungus Fusarium oxysporum. In addition, filamentous fungi are applied in multi-organism and consolidated process configurations. Organism performance and technology readiness are categorized as near-term (<5 years), mid-term (5-10 years), and long-term (>10 years) process deployment. The results of the analysis suggest that the opportunity for fungal fermentation exists for lignocellulosic ethanol production.

  15. 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...

  16. Recycling Cellulase from Enzymatic Hydrolyzate of Laser-Pretreated Corn Stover by UF Membrane

    Directory of Open Access Journals (Sweden)

    Shuang-Qi Tian

    2015-09-01

    Full Text Available The ultrafiltration membrane reactor, utilizing a membrane module with a suitable molecular weight alleyway, retains the larger cellulase components. Smaller molecules, such as the fermentable reducing sugars and water, pass through the membrane. The purpose of this work was to investigate the capability of recycling cellulase in the UF membrane. PS30 hollow fiber membrane, an ultrafiltration method using internal pressure, was found to be an ideal membrane separation device, allowing re-use of the enzyme. A Box-Behnken experimental design (BBD established the following optimum pretreatment parameters: operation pressure at 1.73 bar, temperature at 36.38 °C, and a pH of 5.92. Under these conditions, the model predicted a membrane flux yield of 2.3174 L/(m2•h. The rejection rate of the UF membrane was over 95%.

  17. Furfural and ethanol production from corn stover by dilute phosphoric acid pretreatment

    Science.gov (United States)

    Lignocellulosic biomass is the most abundant carbohydrate source in the world and has potential for economical production of biofuels, especially ethanol. However, its composition is an obstacle for the production of ethanol by the conventional ethanol producing yeast Saccharomyces cerevisiae as it...

  18. 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

    to the different pretreatment times. The glucan recovered from liquid was from 4.9% to 5.6% and the total glucan recoveries from all the pretreatments were higher than 98%. Besides HMF and furfural, acetic, lactic, formic and glycolic acids were also found in the liquid phase. All the concentrations...

  19. 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)

  20. Enzymatic digestibility and ethanol fermentability of AFEX-treated starch-rich lignocellulosics such as corn silage and whole corn plant

    Directory of Open Access Journals (Sweden)

    Thelen Kurt D

    2010-06-01

    Full Text Available Abstract Background Corn grain is an important renewable source for bioethanol production in the USA. Corn ethanol is currently produced by steam liquefaction of starch-rich grains followed by enzymatic saccharification and fermentation. Corn stover (the non-grain parts of the plant is a potential feedstock to produce cellulosic ethanol in second-generation biorefineries. At present, corn grain is harvested by removing the grain from the living plant while leaving the stover behind on the field. Alternatively, whole corn plants can be harvested to cohydrolyze both starch and cellulose after a suitable thermochemical pretreatment to produce fermentable monomeric sugars. In this study, we used physiologically immature corn silage (CS and matured whole corn plants (WCP as feedstocks to produce ethanol using ammonia fiber expansion (AFEX pretreatment followed by enzymatic hydrolysis (at low enzyme loadings and cofermentation (for both glucose and xylose using a cellulase-amylase-based cocktail and a recombinant Saccharomyces cerevisiae 424A (LNH-ST strain, respectively. The effect on hydrolysis yields of AFEX pretreatment conditions and a starch/cellulose-degrading enzyme addition sequence for both substrates was also studied. Results AFEX-pretreated starch-rich substrates (for example, corn grain, soluble starch had a 1.5-3-fold higher enzymatic hydrolysis yield compared with the untreated substrates. Sequential addition of cellulases after hydrolysis of starch within WCP resulted in 15-20% higher hydrolysis yield compared with simultaneous addition of hydrolytic enzymes. AFEX-pretreated CS gave 70% glucan conversion after 72 h of hydrolysis for 6% glucan loading (at 8 mg total enzyme loading per gram glucan. Microbial inoculation of CS before ensilation yielded a 10-15% lower glucose hydrolysis yield for the pretreated substrate, due to loss in starch content. Ethanol fermentation of AFEX-treated (at 6% w/w glucan loading CS hydrolyzate (resulting

  1. Enzymatic digestibility and ethanol fermentability of AFEX-treated starch-rich lignocellulosics such as corn silage and whole corn plant

    Science.gov (United States)

    2010-01-01

    Background Corn grain is an important renewable source for bioethanol production in the USA. Corn ethanol is currently produced by steam liquefaction of starch-rich grains followed by enzymatic saccharification and fermentation. Corn stover (the non-grain parts of the plant) is a potential feedstock to produce cellulosic ethanol in second-generation biorefineries. At present, corn grain is harvested by removing the grain from the living plant while leaving the stover behind on the field. Alternatively, whole corn plants can be harvested to cohydrolyze both starch and cellulose after a suitable thermochemical pretreatment to produce fermentable monomeric sugars. In this study, we used physiologically immature corn silage (CS) and matured whole corn plants (WCP) as feedstocks to produce ethanol using ammonia fiber expansion (AFEX) pretreatment followed by enzymatic hydrolysis (at low enzyme loadings) and cofermentation (for both glucose and xylose) using a cellulase-amylase-based cocktail and a recombinant Saccharomyces cerevisiae 424A (LNH-ST) strain, respectively. The effect on hydrolysis yields of AFEX pretreatment conditions and a starch/cellulose-degrading enzyme addition sequence for both substrates was also studied. Results AFEX-pretreated starch-rich substrates (for example, corn grain, soluble starch) had a 1.5-3-fold higher enzymatic hydrolysis yield compared with the untreated substrates. Sequential addition of cellulases after hydrolysis of starch within WCP resulted in 15-20% higher hydrolysis yield compared with simultaneous addition of hydrolytic enzymes. AFEX-pretreated CS gave 70% glucan conversion after 72 h of hydrolysis for 6% glucan loading (at 8 mg total enzyme loading per gram glucan). Microbial inoculation of CS before ensilation yielded a 10-15% lower glucose hydrolysis yield for the pretreated substrate, due to loss in starch content. Ethanol fermentation of AFEX-treated (at 6% w/w glucan loading) CS hydrolyzate (resulting in 28 g/L ethanol

  2. 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

  3. Effect of alkaline pretreatment on anaerobic digestion of solid wastes

    International Nuclear Information System (INIS)

    Lopez Torres, M.; Espinosa Llorens, Ma. del C.

    2008-01-01

    The introduction of the anaerobic digestion for the treatment of the organic fraction of municipal solid waste (OFMSW) is currently of special interest. The main difficulty in the treatment of this waste fraction is its biotransformation, due to the complexity of organic material. Therefore, the first step must be its physical, chemical and biological pretreatment for breaking complex molecules into simple monomers, to increase solubilization of organic material and improve the efficiency of the anaerobic treatment in the second step. This paper describes chemical pretreatment based on lime addition (Ca(OH) 2 ), in order to enhance chemical oxygen demand (COD) solubilization, followed by anaerobic digestion of the OFMSW. Laboratory-scale experiments were carried out in completely mixed reactors, 1 L capacity. Optimal conditions for COD solubilization in the first step of pretreatment were 62.0 mEq Ca(OH) 2 /L for 6.0 h. Under these conditions, 11.5% of the COD was solubilized. The anaerobic digestion efficiency of the OFMSW, with and without pretreatment, was evaluated. The highest methane yield under anaerobic digestion of the pretreated waste was 0.15 m 3 CH 4 /kg volatile solids (VS), 172.0% of the control. Under that condition the soluble COD and VS removal were 93.0% and 94.0%, respectively. The results have shown that chemical pretreatment with lime, followed by anaerobic digestion, provides the best results for stabilizing the OFMSW

  4. Alkaline pretreatment of Mexican pine residues for bioethanol ...

    African Journals Online (AJOL)

    CLAUDIA

    2013-07-31

    Jul 31, 2013 ... 120°C. The pretreated blending was subjected to enzymatic hydrolysis for 130 h at 80 rpm and 50°C with an enzymatic load of ... pretreatment of 2.5% NaOH for 90 min, 120°C, and a hydrolysis residence time of 130 h. The removal of ...... Programa Estratégico Forestal para el estado de Durango,. México.

  5. 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.

  6. Crop Management Effects on the Energy and Carbon Balances of Maize Stover-Based Ethanol Production

    Directory of Open Access Journals (Sweden)

    Prem Woli

    2014-12-01

    Full Text Available This study was conducted to identify the crop management options—the combinations of various cultivars, irrigation amounts, planting dates, and soils—that would maximize the energy sustainability and eco-friendliness of maize (Zea mays L. stover-based ethanol production systems in the Mississippi Delta. Stover yields simulated with CERES-Maize were used to compute net energy value (NEV and carbon credit balance (CCB, the indicators of sustainability and eco-friendliness of ethanol production, respectively, for various scenarios. As the results showed, deeper soils with higher water holding capacities had larger NEV and CCB values. Both NEV and CCB had sigmoid relationships with irrigation amount and planting date and could be maximized by planting the crop during the optimum planting window. Stover yield had positive effects on NEV and CCB, whereas travel distance had negative. The influence of stover yield was larger than that of travel distance, indicating that increasing feedstock yields should be emphasized over reducing travel distance. The NEV and CCB values indicated that stover-based ethanol production in the Mississippi Delta is sustainable and environmentally friendly. The study demonstrated that the energy sustainability and eco-friendliness of maize stover-based ethanol production could be increased with alternative crop management options.

  7. CORN, LP Goldfield Approval

    Science.gov (United States)

    This November 19, 2015 letter from EPA approves the petition from CORN, LP, Goldfield facility, regarding non-grandfathered ethanol produced through a dry mill process, qualifying under the Clean Air Act for renewable fuel (D-code 6) RINs under the RFS pro

  8. Residual nitrogen-15 recovery by corn as influenced by tillage and fertilization method

    International Nuclear Information System (INIS)

    Timmons, D.R.; Cruse, R.M.

    1991-01-01

    Tillage systems that create different surface residue conditions may also affect the recovery of residual fertilizer N during subsequent growing seasons. This study evaluated the recovery of residual labeled N fertilizer in the soil by corn (Zea mays L.) for two tillage systems and two fertilization methods. Five atom % 15 N-enriched 28% urea-ammonium nitrate solution (UAN) at 224 kg N ha -1 was either surface-applied in the fall before any primary tillage or banded (knifed in) just before planting in the spring. Continuous corn was grown with either fall moldboard-plow (MP) or ridge-till (RT) systems. After the initial growing season, the recovery of residual labeled N in the soil by corn was determined for three consecutive growing seasons, and the soil profile was sampled periodically to measure residual 15 N in the organic and inorganic pools. One year after labeled UAN application, from 16 to 27% of the initial 15 N applied was found in the organic N pool and only 1% as inorganic N[NH 4 +(NO 2 +NO 3 )-N]. After four seasons, residual 15 N in the organic N pool ranged from 13 to 24%. Less than 0.5% remained as inorganic N. Regression analyses indicated that about 5 kg 15 N ha -1 year -1 became available for both MP and RT systems with banded N, so the amounts were small. Total residual 15 N recovery by corn grain plus stover for three seasons ranged from 1.7 to 3.5%, and was greatest for spring-banded fertilizer. Because the amounts of residual 15 N utilized were too small to affect corn growth, this N source appears to be negligible when considering corn-N needs

  9. The Wandering of Corn

    OpenAIRE

    Salov, Valerii

    2017-01-01

    Time and Sales of corn futures traded electronically on the CME Group Globex are studied. Theories of continuous prices turn upside down reality of intra-day trading. Prices and their increments are discrete and obey lattice probability distributions. A function for systematic evolution of futures trading volume is proposed. Dependence between sample skewness and kurtosis of waiting times does not support hypothesis of Weibull distribution. Kumaraswamy distribution is more suitable for waitin...

  10. 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 codi...

  11. Densification characteristics of corn cobs

    Energy Technology Data Exchange (ETDEWEB)

    Kaliyan, Nalladurai; Morey, R. Vance [Department of Bioproducts and Biosystems Engineering, University of Minnesota, 1390 Eckles Avenue, St. Paul, MN 55108 (United States)

    2010-05-15

    Corn cobs are potential feedstocks for producing heat, power, fuels, and chemicals. Densification of corn cobs into briquettes/pellets would improve their bulk handling, transportation, and storage properties. In this study, densification characteristics of corn cobs were studied using a uniaxial piston-cylinder densification apparatus. With a maximum compression pressure of 150 MPa, effects of particle size (0.85 and 2.81 mm), moisture content (10 and 20% w.b.), and preheating temperature (25 and 85 C) on the density and durability of the corn cob briquettes (with diameter of about 19.0 mm) were studied. It was found that the durability (measured using ASABE tumbling can method) of corn cob briquettes made at 25 C was 0%. At both particle sizes, preheating of corn cob grinds with about 10% (w.b.) moisture content to 85 C produced briquettes with a unit density of > 1100 kg m{sup -3} and durability of about 90%. (author)

  12. Cellulase production through solid-state tray fermentation, and its use for bioethanol from sorghum stover.

    Science.gov (United States)

    Idris, Ayman Salih Omer; Pandey, Ashok; Rao, S S; Sukumaran, Rajeev K

    2017-10-01

    The production of cellulase by Trichoderma reesei RUT C-30 under solid-state fermentation (SSF) on wheat bran and cellulose was optimized employing a two stage statistical design of experiments. Optimization of process parameters resulted in a 3.2-fold increase in CMCase production to 959.53IU/gDS. The process was evaluated at pilot scale in tray fermenters and yielded 457IU/gDS using the lab conditions and indicating possibility for further improvement. The cellulase could effectively hydrolyze alkali pretreated sorghum stover and addition of Aspergillus niger β-glucosidase improved the hydrolytic efficiency 174%, indicating the potential to use this blend for effective saccharification of sorghum stover biomass. The enzymatic hydrolysate of sorghum stover was fermented to ethanol with ∼80% efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Size reduction of high- and low-moisture corn stalks by linear knife grid system

    Energy Technology Data Exchange (ETDEWEB)

    Igathinathane, C. [Agricultural and Biological Engineering Department, 130 Creelman Street, Mississippi State University, Mississippi State, Mississippi 39762 (United States); Womac, A.R. [Department of Biosystems Engineering and Soil Science, 2506 E. J. Chapman Drive, The University of Tennessee, Knoxville, Tennessee 37996 (United States); Sokhansanj, S. [Oak Ridge National Laboratory, Environmental Sciences Division, Oak Ridge, P. O. Box 2008, Tennessee 37831 (United States); Narayan, S. [First American Scientific Company, 100 Park Royal South West Vancouver, British Columbia, V7T 1A2 (Canada)

    2009-04-15

    High- and low-moisture corn stalks were tested using a linear knife grid size reduction device developed for first-stage size reduction. The device was used in conjunction with a universal test machine that quantified shearing stress and energy characteristics for forcing a bed of corn stalks through a grid of sharp knives. No published engineering performance data for corn stover with similar devices are available to optimize performance; however, commercial knife grid systems exist for forage size reduction. From the force-displacement data, mean and maximum ultimate shear stresses, cumulative and peak mass-based cutting energies for corn stalks, and mean new surface area-based cutting energies were determined from 4-5 refill runs at two moisture contents (78.8% and 11.3% wet basis), three knife grid spacings (25.4, 50.8, and 101.6 mm), and three bed depths (50.8, 101.6, and 152.4 mm). In general, the results indicated that peak failure load, ultimate shear stress, and cutting energy values varied directly with bed depth and inversely with knife grid spacing. Mean separation analysis established that high- and low-moisture conditions and bed depths {>=} 101.6 mm did not differ significantly (P < 0.05) for ultimate stress and cutting energy values, but knife grid spacing were significantly different. Linear knife grid cutting energy requirements for both moisture conditions of corn stalks were much smaller than reported cutting energy requirements. Ultimate shear stress and cutting energy results of this research should aid the engineering design of commercial scale linear knife gird size reduction equipment for various biomass feedstocks. (author)

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

    Science.gov (United States)

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

    2013-01-01

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

  15. Adsorption and mechanism of cellulase enzymes onto lignin isolated from corn stover pretreated with liquid hot water

    OpenAIRE

    Lu, Xianqin; Zheng, Xiaoju; Li, Xuezhi; Zhao, Jian

    2016-01-01

    Background In the bioconversion of lignocellulosic substrates, the adsorption behavior of cellulase onto lignin has a negative effect on enzymatic hydrolysis of cellulose, decreasing glucose production during enzymatic hydrolysis, thus decreasing the yield of fermentation and the production of useful products. Understanding the interaction between lignin and cellulase is necessary to optimize the components of cellulase mixture, genetically engineer high-efficiency cellulase, and reduce cost ...

  16. Development of the IBSAL-SimMOpt Method for the Optimization of Quality in a Corn Stover Supply Chain

    Directory of Open Access Journals (Sweden)

    Hernan Chavez

    2017-08-01

    Full Text Available Variability on the physical characteristics of feedstock has a relevant effect on the reactor’s reliability and operating cost. Most of the models developed to optimize biomass supply chains have failed to quantify the effect of biomass quality and preprocessing operations required to meet biomass specifications on overall cost and performance. The Integrated Biomass Supply Analysis and Logistics (IBSAL model estimates the harvesting, collection, transportation, and storage cost while considering the stochastic behavior of the field-to-biorefinery supply chain. This paper proposes an IBSAL-SimMOpt (Simulation-based Multi-Objective Optimization method for optimizing the biomass quality and costs associated with the efforts needed to meet conversion technology specifications. The method is developed in two phases. For the first phase, a SimMOpt tool that interacts with the extended IBSAL is developed. For the second phase, the baseline IBSAL model is extended so that the cost for meeting and/or penalization for failing in meeting specifications are considered. The IBSAL-SimMOpt method is designed to optimize quality characteristics of biomass, cost related to activities intended to improve the quality of feedstock, and the penalization cost. A case study based on 1916 farms in Ontario, Canada is considered for testing the proposed method. Analysis of the results demonstrates that this method is able to find a high-quality set of non-dominated solutions.

  17. A generalized disjunctive programming framework for the optimal synthesis and analysis of processes for ethanol production from corn stover.

    Science.gov (United States)

    Scott, Felipe; Aroca, Germán; Caballero, José Antonio; Conejeros, Raúl

    2017-07-01

    The aim of this study is to analyze the techno-economic performance of process configurations for ethanol production involving solid-liquid separators and reactors in the saccharification and fermentation stage, a family of process configurations where few alternatives have been proposed. Since including these process alternatives creates a large number of possible process configurations, a framework for process synthesis and optimization is proposed. This approach is supported on kinetic models fed with experimental data and a plant-wide techno-economic model. Among 150 process configurations, 40 show an improved MESP compared to a well-documented base case (BC), almost all include solid separators and some show energy retrieved in products 32% higher compared to the BC. Moreover, 16 of them also show a lower capital investment per unit of ethanol produced per year. Several of the process configurations found in this work have not been reported in the literature. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Relating Nanoscale Accessibility within Plant Cell Walls to Improved Enzyme Hydrolysis Yields in Corn Stover Subjected to Diverse Pretreatments.

    Science.gov (United States)

    Crowe, Jacob D; Zarger, Rachael A; Hodge, David B

    2017-10-04

    Simultaneous chemical modification and physical reorganization of plant cell walls via alkaline hydrogen peroxide or liquid hot water pretreatment can alter cell wall structural properties impacting nanoscale porosity. Nanoscale porosity was characterized using solute exclusion to assess accessible pore volumes, water retention value as a proxy for accessible water-cell walls surface area, and solute-induced cell wall swelling to measure cell wall rigidity. Key findings concluded that delignification by alkaline hydrogen peroxide pretreatment decreased cell wall rigidity and that the subsequent cell wall swelling resulted increased nanoscale porosity and improved enzyme binding and hydrolysis compared to limited swelling and increased accessible surface areas observed in liquid hot water pretreated biomass. The volume accessible to a 90 Å dextran probe within the cell wall was found to be correlated to both enzyme binding and glucose hydrolysis yields, indicating cell wall porosity is a key contributor to effective hydrolysis yields.

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

    Science.gov (United States)

    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) emis-sions, and global warming potential (GWP) in irrigated systems, however,...

  20. Mechanisms of antimony adsorption onto soybean stover-derived biochar in aqueous solutions

    Science.gov (United States)

    Limited mechanistic knowledge is available to understand how biochar interacts with trace elements that exist predominantly as oxoanions, such as antimony (Sb). Soybean stover biochars were produced at 300 degrees C (SBC300) and 700 degrees C (SBC700), and were characterized by BET, Boehm titration,...

  1. Corn in consortium with forages

    Directory of Open Access Journals (Sweden)

    Cássia Maria de Paula Garcia

    2013-12-01

    Full Text Available The basic premises for sustainable agricultural development with focus on rural producers are reducing the costs of production and aggregation of values through the use crop-livestock system (CLS throughout the year. The CLS is based on the consortium of grain crops, especially corn with tropical forages, mainly of the genus Panicum and Urochloa. The study aimed to evaluate the grain yield of irrigated corn crop intercropped with forage of the genus Panicum and Urochloa. The experiment was conducted at the Fazenda de Ensino, Pesquisa e Extensão – FEPE  of the Faculdade de Engenharia - UNESP, Ilha Solteira in an Oxisol in savannah conditions and in the autumn winter of 2009. The experimental area was irrigated by a center pivot and had a history of no-tillage system for 8 years. The corn hybrid used was simple DKB 390 YG at distances of 0.90 m. The seeds of grasses were sown in 0.34 m spacing in the amount of 5 kg ha-1, they were mixed with fertilizer minutes before sowing  and placed in a compartment fertilizer seeder and fertilizers were mechanically deposited in the soil at a depth of 0.03 m. The experimental design used was a randomized block with four replications and five treatments: Panicum maximum cv. Tanzania sown during the nitrogen fertilization (CTD of the corn; Panicum maximum cv. Mombaça sown during the nitrogen fertilization (CMD of the corn; Urochloa brizantha cv. Xaraés sown during the occasion of nitrogen fertilization (CBD of the corn; Urochloa ruziziensis cv. Comumsown during the nitrogen fertilization (CRD of the corn and single corn (control. The production components of corn: plant population per hectare (PlPo, number of ears per hectare (NE ha-1, number of rows per ear (NRE, number of kernels per row on the cob (NKR, number of grain in the ear (NGE and mass of 100 grains (M100G were not influenced by consortium with forage. Comparing grain yield (GY single corn and maize intercropped with forage of the genus Panicum

  2. Corn Culture: A Story of Intelligent Design

    Science.gov (United States)

    Todd, Jude

    2008-01-01

    Scientists are not sure of how corn was created. There were two competing genetic theories about how corn came to be. One theory maintains that corn had been teased out of a wheatlike grass called teosinte (genus Zea), and the other contends that one now-extinct ancestor of corn had crossed with another grass, "Tripsacum," several millennia ago.…

  3. Digestibility and performance of steers fed low-quality crop residues treated with calcium oxide to partially replace corn in distillers grains finishing diets.

    Science.gov (United States)

    Shreck, A L; Nuttelman, B L; Harding, J L; Griffin, W A; Erickson, G E; Klopfenstein, T J; Cecava, M J

    2015-02-01

    Two studies were conducted to identify methods for treating crop residues to improve digestibility and value in finishing diets based on corn grain and corn wet distillers grain with solubles (WDGS). In Exp. 1, 336 yearling steers (initial BW 356 ± 11.5 kg) were used in a 2 × 3 + 1 factorial arrangement of treatments with 6 pens per treatment. Factors were 3 crop residues (corn cobs, wheat straw, and corn stover) and 2 treatments where crop residues were either fed (20% diet DM) in their native form (NT) or alkaline treated with 5% CaO (DM basis) and hydrated to 50% DM before anaerobic storage (AT). Intakes were not affected by diet (F test; P = 0.30). An interaction between chemical treatment and residue (P 0.10) was observed between control (46% corn; DM basis) and AT (31% corn; DM basis) for DM digestibility (70.7% vs. 73.7%) or OM digestibility (72.1% vs. 77.0%). Dry matter intakes were not different between treated and untreated diets (P = 0.38), but lower (P < 0.01) NDF intake was observed for treated diets (3.1 vs. 3.5 kg/d), suggesting that CaO treatment was effective in solubilizing some carbohydrate. These data suggest that 15% replacement of corn and 10% untreated residue with treated forage result in a nutrient supply of OM similar to that of the control. The improvements in total tract fiber digestibility that occurred when treated forages were fed may have been related to increased digestibility of recoverable NDF and not to increased ruminal pH. Feeding chemically treated crop residues and WDGS is an effective strategy for replacing a portion of corn grain and roughage in feedlot diets.

  4. Ethanol extraction of phytosterols from corn fiber

    Science.gov (United States)

    Abbas, Charles; Beery, Kyle E.; Binder, Thomas P.; Rammelsberg, Anne M.

    2010-11-16

    The present invention provides a process for extracting sterols from a high solids, thermochemically hydrolyzed corn fiber using ethanol as the extractant. The process includes obtaining a corn fiber slurry having a moisture content from about 20 weight percent to about 50 weight percent solids (high solids content), thermochemically processing the corn fiber slurry having high solids content of 20 to 50% to produce a hydrolyzed corn fiber slurry, dewatering the hydrolyzed corn fiber slurry to achieve a residual corn fiber having a moisture content from about 30 to 80 weight percent solids, washing the residual corn fiber, dewatering the washed, hydrolyzed corn fiber slurry to achieve a residual corn fiber having a moisture content from about 30 to 80 weight percent solids, and extracting the residual corn fiber with ethanol and separating at least one sterol.

  5. 21 CFR 184.1321 - Corn gluten.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Corn gluten. 184.1321 Section 184.1321 Food and... Substances Affirmed as GRAS § 184.1321 Corn gluten. (a) Corn gluten (CAS Reg. No. 66071-96-3), also known as corn gluten meal, is the principal protein component of corn endosperm. It consists mainly of zein and...

  6. Protein determination in single corns

    International Nuclear Information System (INIS)

    Knorr, J.; Schiekel, M.; Franke, W.; Focke, F.

    1994-01-01

    Determination of protein content in food materials is usually done by analyzing the nitrogen amount by wet chemical Kjeldahl method. An improved accuracy accompanied by smaller analyzing intervals can be achieved using nondestructive neutron activation. Analyses have been performed using 14 MeV neutrons to determine the content of N and P in single wheat corns. Irradiation parameters have been optimized to prevent serious radiation damage in grains. About 200 single corns have been investigated with total net weights ranging from 30 to 70 mg. The tested arrangement allows determination of nitrogen amount in a single corn down to 0.3 mg with an accuracy of better than 4 %. Mean nitrogen concentrations in the range from 9 to 19% per corn have been detected. (author) 5 refs.; 6 figs

  7. Rapid optimization of enzyme mixtures for deconstruction of diverse pretreatment/biomass feedstock combinations

    Directory of Open Access Journals (Sweden)

    Walton Jonathan D

    2010-10-01

    Full Text Available Abstract Background Enzymes for plant cell wall deconstruction are a major cost in the production of ethanol from lignocellulosic biomass. The goal of this research was to develop optimized synthetic mixtures of enzymes for multiple pretreatment/substrate combinations using our high-throughput biomass digestion platform, GENPLAT, which combines robotic liquid handling, statistical experimental design and automated Glc and Xyl assays. Proportions of six core fungal enzymes (CBH1, CBH2, EG1, β-glucosidase, a GH10 endo-β1,4-xylanase, and β-xylosidase were optimized at a fixed enzyme loading of 15 mg/g glucan for release of Glc and Xyl from all combinations of five biomass feedstocks (corn stover, switchgrass, Miscanthus, dried distillers' grains plus solubles [DDGS] and poplar subjected to three alkaline pretreatments (AFEX, dilute base [0.25% NaOH] and alkaline peroxide [AP]. A 16-component mixture comprising the core set plus 10 accessory enzymes was optimized for three pretreatment/substrate combinations. Results were compared to the performance of two commercial enzymes (Accellerase 1000 and Spezyme CP at the same protein loadings. Results When analyzed with GENPLAT, corn stover gave the highest yields of Glc with commercial enzymes and with the core set with all pretreatments, whereas corn stover, switchgrass and Miscanthus gave comparable Xyl yields. With commercial enzymes and with the core set, yields of Glc and Xyl were highest for grass stovers pretreated by AP compared to AFEX or dilute base. Corn stover, switchgrass and DDGS pretreated with AFEX and digested with the core set required a higher proportion of endo-β1,4-xylanase (EX3 and a lower proportion of endo-β1,4-glucanase (EG1 compared to the same materials pretreated with dilute base or AP. An optimized enzyme mixture containing 16 components (by addition of α-glucuronidase, a GH11 endoxylanase [EX2], Cel5A, Cel61A, Cip1, Cip2, β-mannanase, amyloglucosidase,

  8. Water and Land Use Efficiency in Current and Potential Future US Corn and Brazilian Sugarcane Ethanol Systems

    Science.gov (United States)

    Warner, E. S.; Zhang, Y.; Newmark, R. L.

    2012-12-01

    average sugarcane ethanol system producing ethanol and electricity can save about 13 Mg CO2eq/ha of land compared to 12 in the early 2000s, while a recent average corn ethanol system saves about 6.2 Mg CO2eq/ha compared to near zero GHG savings in the early 2000s. The net energy balance (i.e., energy produced minus energy consumed) per ha for a recent average sugarcane ethanol system producing both ethanol and electricity is about 160 GJ/ha compared to 140 GJ/ha in early 2000s, while the recent average corn ethanol system achieves a net energy production of about 90 GJ/ha compares to only 30 GJ/ha in the early 2000s. The land use efficiency of corn and sugarcane ethanol systems, especially future systems, can vary depending on factors such as the assumed technologies, the suite of co-products produced, field practices, and technological learning. For example, projected future (2020) advanced sugarcane ethanol systems could save 22 Mg CO2eq/ha while an advanced corn ethanol system using integrated gasification of corn stover for electricity production could save 9.3Mg CO2eq/ha. Future advanced sugarcane ethanol systems could produce 210 GJ of net energy/ha while an advanced corn ethanol system using integrated gasification of corn stover for electricity production could achieve 110 GJ/ha.

  9. WHAT IS THE VALUE OF BT CORN?

    OpenAIRE

    Hurley, Terrance M.; Mitchell, Paul D.; Rice, Marlin E.

    2001-01-01

    A common perception is that the value of Bt corn arises from two components-Bt corn increases expected profit and reduces profit variability. This perception encourages farmers and the policy makers to add a risk benefit to estimates of the value of Bt corn to account for the variability reduction. However, a conceptual model generates a useful decomposition of the value of Bt corn and a condition determining the impact of Bt corn on profit variability. An empirical model finds that Bt corn i...

  10. Fact sheet: Ethanol from corn

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-05-31

    This fact sheet is intended to provide an overview of the advantages of ethanol from corn, emphasizing ethanol`s contribution to environmental protection and sustainable agriculture. Ethanol, an alternative fuel used as an octane enhancer is produced through the conversion of starch to sugars by enzymes, and fermentation of these sugars to ethanol by yeast. The production process may involve wet milling or dry milling. Both these processes produce valuable by-products, in addition to ethanol and carbon dioxide. Ethanol contains about 32,000 BTU per litre. It is commonly believed that using state-of-the-art corn farming and corn processing processes, the amount of energy contained in ethanol and its by-products would be more than twice the energy required to grow and process corn into ethanol. Ethanol represents the third largest market for Ontario corn, after direct use as animal feed and wet milling for starch, corn sweetener and corn oil. The environmental consequences of using ethanol are very significant. It is estimated that a 10 per cent ethanol blend in gasoline would result in a 25 to 30 per cent decrease in carbon monoxide emissions, a 6 to 10 per cent decrease in net carbon dioxide, a slight increase in nitrous oxide emissions which, however, would still result in an overall decrease in ozone formation, since the significant reduction in carbon monoxide emissions would compensate for any slight increase in nitrous oxide. Volatile organic compounds emission would also decrease by about 7 per cent with a 10 per cent ethanol blend. High level blends could reduce VOCs production by as much as 30 per cent. 7 refs.

  11. 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.

  12. Impact of Corn Earworm (Lepidoptera: Noctuidae) on Field Corn (Poales: Poaceae) Yield and Grain Quality.

    Science.gov (United States)

    Bibb, Jenny L; Cook, Donald; Catchot, Angus; Musser, Fred; Stewart, Scott D; Leonard, Billy Rogers; Buntin, G David; Kerns, David; Allen, Tom W; Gore, Jeffrey

    2018-05-28

    Corn earworm, Helicoverpa zea (Boddie), commonly infests field corn, Zea mays (L.). The combination of corn plant biology, corn earworm behavior in corn ecosystems, and field corn value renders corn earworm management with foliar insecticides noneconomical. Corn technologies containing Bacillus thuringiensis (Bt) Berliner (Bacillales: Bacillaceae) were introduced that exhibit substantial efficacy against corn earworm and may reduce mycotoxin contamination in grain. The first generation Bt traits in field corn demonstrated limited activity on corn earworm feeding on grain. The pyramided corn technologies have greater cumulative protein concentrations and higher expression throughout the plant, so these corn traits should provide effective management of this pest. Additionally, reduced kernel injury may affect physical grain quality. Experiments were conducted during 2011-2012 to investigate corn earworm impact on field corn yield and grain quality. Treatments included field corn hybrids expressing the Herculex, YieldGard, and Genuity VT Triple Pro technologies. Supplemental insecticide treatments were applied every 1-2 d from silk emergence until silk senescence to create a range of injured kernels for each technology. No significant relationship between the number of corn earworm damaged kernels and yield was observed for any technology/hybrid. In these studies, corn earworm larvae did not cause enough damage to impact yield. Additionally, no consistent relationship between corn earworm damage and aflatoxin contamination was observed. Based on these data, the economic value of pyramided Bt corn traits to corn producers, in the southern United States, appears to be from management of other lepidopteran insect pests including European and southwestern corn borer.

  13. 21 CFR 155.131 - Canned field corn.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Canned field corn. 155.131 Section 155.131 Food... Canned field corn. (a) Identity. (1) Canned field corn conforms to the definition and standard of... corn by § 155.130(a), except that the corn ingredient consists of succulent field corn or a mixture of...

  14. 21 CFR 184.1857 - Corn sugar.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Corn sugar. 184.1857 Section 184.1857 Food and... Substances Affirmed as GRAS § 184.1857 Corn sugar. (a) Corn sugar (C6H12O6, CAS Reg. No. 50-99-7), commonly... monohydrate form and is produced by the complete hydrolysis of corn starch with safe and suitable acids or...

  15. 21 CFR 184.1865 - Corn syrup.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Corn syrup. 184.1865 Section 184.1865 Food and... Substances Affirmed as GRAS § 184.1865 Corn syrup. (a) Corn syrup, commonly called “glucose sirup” or “glucose syrup,” is obtained by partial hydrolysis of corn starch with safe and suitable acids or enzymes...

  16. Utilization of Different Corn Fractions by Broilers

    OpenAIRE

    Costa, SIFR; Stringhini, JH; Ribeiro, AML; Pontalti, G; MacManus, C

    2015-01-01

    ABSTRACTThis study was conducted to evaluate the nutritional values of fractions of damaged corn. One hundred and eighty 22-d-old Cobb 500 male broilers were distributed in batteries according to a completely randomized design with six treatments of six replicates each. The treatments consisted of diets containing five corn fractions, classified as sound, fermented, insect-damaged, mold-damaged, or reference corn. The test diets consisted of 60% of reference diet + 40% of each corn fraction. ...

  17. THE CORN-EGG PRICE TRANSMISSION MECHANISM

    OpenAIRE

    Babula, Ronald A.; Bessler, David A.

    1990-01-01

    A vector autoregression (VAR) model of corn, farm egg, and retail egg prices is estimated and shocked with a corn price increase. Impulse responses in egg prices, t-statistics for the impulse responses, and decompositions of forecast error variance are presented. Analyses of results provide insights on the corn/egg price transmission mechanism and on how corn price shocks pulsate through the egg-related economy.

  18. Corned Beef: an Enigmatic Irish Dish

    OpenAIRE

    Mac Con Iomaire, Máirtín; Gallagher, Pádraic Óg

    2011-01-01

    Corned beef and cabbage, which is consumed in America in large quantities each Saint Patrick’s Day (17th March), is considered by most Americans to be the ultimate Irish dish. However, corned beef and cabbage is seldom eaten in modern day Ireland. It is widely reported that Irish immigrants replaced their beloved bacon and cabbage with corned beef and cabbage when they arrived in America, drawing on the corned beef supplied by their neighbouring Jewish butchers, but not all commentators beli...

  19. "King Corn": Teaching the Food Crisis

    Science.gov (United States)

    Swinehart, Tim

    2012-01-01

    "King Corn" is in so many ways the story of how government food policy has entirely remade the food landscape in the United States over the last 40 years. From the massive expansion of the number of acres of corn grown across the country, to the ever-increasing ways that corn is incorporated into the food production process, to the…

  20. Does Bt Corn Really Produce Tougher Residues

    Science.gov (United States)

    Bt corn hybrids produce insecticidal proteins that are derived from a bacterium, Bacillus thuringiensis. There have been concerns that Bt corn hybrids produce residues that are relatively resistant to decomposition. We conducted four experiments that examined the decomposition of corn residues und...

  1. Nitrogen Soil Testing for Corn in Virginia

    OpenAIRE

    Evanylo, Gregory K.; Alley, Marcus M., 1947-

    2009-01-01

    An adequate supply of plant-available nitrogen (N) is crucial for efficient corn production, and corn N requirements are greater than any other nutrient. This publication reviews the link between nitrogen and corn production, nitrogen behavior, soil testing, test procedures and recommendations.

  2. Geographic information systems in corn rootworm management

    Science.gov (United States)

    Corn rootworms (Diabrotica spp. Coleoptera: Chrysomelidae) are serious pests of corn (Zea mays) in the United States and Europe. Control measures for corn rootworms (CRW) were historically based upon chemical pesticides and crop rotation. Pesticide use created environmental and economic concerns. In...

  3. Effects of replacing conventional corn silage with BMR corn silage

    Science.gov (United States)

    Previous research has shown that the (lignin reducing) brown mid-rib mutation in corn silage, which increases in vitro fiber digestibility, does not always improve fiber digestibility when fed as part of a TMR; however, feed intake and milk production are increased. The objectives of this experiment...

  4. Influence of corn oil recovery on life-cycle greenhouse gas emissions of corn ethanol and corn oil biodiesel.

    Science.gov (United States)

    Wang, Zhichao; Dunn, Jennifer B; Han, Jeongwoo; Wang, Michael Q

    2015-01-01

    Corn oil recovery and conversion to biodiesel has been widely adopted at corn ethanol plants recently. The US EPA has projected 2.6 billion liters of biodiesel will be produced from corn oil in 2022. Corn oil biodiesel may qualify for federal renewable identification number (RIN) credits under the Renewable Fuel Standard, as well as for low greenhouse gas (GHG) emission intensity credits under California's Low Carbon Fuel Standard. Because multiple products [ethanol, biodiesel, and distiller's grain with solubles (DGS)] are produced from one feedstock (corn), however, a careful co-product treatment approach is required to accurately estimate GHG intensities of both ethanol and corn oil biodiesel and to avoid double counting of benefits associated with corn oil biodiesel production. This study develops four co-product treatment methods: (1) displacement, (2) marginal, (3) hybrid allocation, and (4) process-level energy allocation. Life-cycle GHG emissions for corn oil biodiesel were more sensitive to the choice of co-product allocation method because significantly less corn oil biodiesel is produced than corn ethanol at a dry mill. Corn ethanol life-cycle GHG emissions with the displacement, marginal, and hybrid allocation approaches are similar (61, 62, and 59 g CO2e/MJ, respectively). Although corn ethanol and DGS share upstream farming and conversion burdens in both the hybrid and process-level energy allocation methods, DGS bears a higher burden in the latter because it has lower energy content per selling price as compared to corn ethanol. As a result, with the process-level allocation approach, ethanol's life-cycle GHG emissions are lower at 46 g CO2e/MJ. Corn oil biodiesel life-cycle GHG emissions from the marginal, hybrid allocation, and process-level energy allocation methods were 14, 59, and 45 g CO2e/MJ, respectively. Sensitivity analyses were conducted to investigate the influence corn oil yield, soy biodiesel, and defatted DGS displacement credits

  5. The U2U Corn Growing Degree Day tool: Tracking corn growth across the US Corn Belt

    Directory of Open Access Journals (Sweden)

    James R. Angel

    2017-01-01

    Full Text Available The Corn Growing Degree Day (Corn GDD tool is a web-based product that can provide decision support on a variety of issues throughout the entire growing season by integrating current conditions, historical climate data, and projections of Corn GDD through the end of the growing season based on both National Weather Service computer model forecasts and climatology. The Corn GDD tool can help agricultural producers make a variety of important decisions before and during the growing season. This support can include: assessing the risk of early and late frosts and freezes that can cause crop damage; comparing corn hybrid maturity requirements and Corn GDD projections to select seed varieties and plan activities such as spraying; guiding marketing decisions based on historical and projected Corn GDDs when considering forward crop pricing (i.e., futures market. The Corn GDD tool provides decision support for corn producers in the central U.S. corn-producing states. Survey results, web statistics, and user feedback indicate that this tool is being actively used by decision makers.

  6. Factors contributing to the recalcitrance of herbaceous dicotyledons (forbs) to enzymatic deconstruction.

    Science.gov (United States)

    Jabbour, Dina; Angelos, Evan R; Mukhopadhyay, Achira; Womboldt, Alec; Borrusch, Melissa S; Walton, Jonathan D

    2014-04-05

    Many different feedstocks are under consideration for the practical production of biofuels from lignocellulosic materials. The best choice under any particular combination of economic, agronomic, and environmental conditions depends on multiple factors. The use of old fields, restored prairie, or marginal lands to grow biofuel feedstocks offers several potential benefits including minimal agronomic inputs, reduced competition with food production, and high biodiversity. However, a major component of such landscapes is often herbaceous dicotyledonous plants, also known as forbs. The potential and obstacles of using forbs as biofuel feedstocks compared to the more frequently considered grasses and woody plants are poorly understood. The factors that contribute to the yield of fermentable sugars from four representative forbs were studied in comparison with corn stover. The forbs chosen for the study were lamb's quarters (Chenopodium album), goldenrod (Solidago canadensis), milkweed (Asclepias syriaca), and Queen Anne's lace (Daucus carota). These plants are taxonomically diverse, widely distributed in northern temperate regions including the continental United States, and are weedy but not invasive. All of the forbs had lower total glucose (Glc) content from all sources (cell walls, sucrose, starch, glucosides, and free Glc) compared to corn stover (range 16.2 to 23.0% on a dry weight basis compared to 39.2% for corn stover). When digested with commercial enzyme mixtures after alkaline pretreatment, yields of Glc as a percentage of total Glc were lower for the forbs compared to corn stover. Enzyme inhibition by water-extractable compounds was not a significant contributor to the lower yields. Based on experiments with optimized cocktails of pure glycosyl hydrolases, enzyme imbalance probably accounted for much of the lower yields. Addition of xyloglucanase and α-xylosidase, two enzymes targeting Glc-containing polysaccharides that are more abundant in dicotyledonous

  7. Utilization of Different Corn Fractions by Broilers

    Directory of Open Access Journals (Sweden)

    SIFR Costa

    2015-09-01

    Full Text Available ABSTRACTThis study was conducted to evaluate the nutritional values of fractions of damaged corn. One hundred and eighty 22-d-old Cobb 500 male broilers were distributed in batteries according to a completely randomized design with six treatments of six replicates each. The treatments consisted of diets containing five corn fractions, classified as sound, fermented, insect-damaged, mold-damaged, or reference corn. The test diets consisted of 60% of reference diet + 40% of each corn fraction. Only the reference corn fraction included all the fractions at different proportions (0.8% fermented, 0.05% insect-damaged, 3.3% mold-damaged, and 95.85% sound grains. The method of total excreta collection was used to determine AMEn values and metabolizability coefficients of dry matter (MDM, crude protein (MCP, ether extract (MEE, and gross energy (MGE of the reference corn and its fractions. The density values of the corn fractions were used to calculate the correlations among the evaluated parameters. The evaluated corn fractions presented different compositions values. The insect-damaged and mold-damaged grains presented higher CP level, lower density, and MDM and MCP coefficients compared with the other fractions. However, calculated AMEn values were not significantly different (p>0.05 among corn fractions. A low correlation between density and AMEn content (r0.8 were calculated. Although the evaluated corn fractions presented different nutritional values, there were no marked differences in their utilization by broilers.

  8. How does cellulosome composition influence deconstruction of lignocellulosic substrates in Clostridium (Ruminiclostridium) thermocellum DSM 1313?

    Science.gov (United States)

    Yoav, Shahar; Barak, Yoav; Shamshoum, Melina; Borovok, Ilya; Lamed, Raphael; Dassa, Bareket; Hadar, Yitzhak; Morag, Ely; Bayer, Edward A

    2017-01-01

    Bioethanol production processes involve enzymatic hydrolysis of pretreated lignocellulosic biomass into fermentable sugars. Due to the relatively high cost of enzyme production, the development of potent and cost-effective cellulolytic cocktails is critical for increasing the cost-effectiveness of bioethanol production. In this context, the multi-protein cellulolytic complex of Clostridium ( Ruminiclostridium ) thermocellum, the cellulosome, was studied here. C. thermocellum is known to assemble cellulosomes of various subunit (enzyme) compositions, in response to the available carbon source. In the current study, different carbon sources were used, and their influence on both cellulosomal composition and the resultant activity was investigated. Glucose, cellobiose, microcrystalline cellulose, alkaline-pretreated switchgrass, alkaline-pretreated corn stover, and dilute acid-pretreated corn stover were used as sole carbon sources in the growth media of C. thermocellum strain DSM 1313. The purified cellulosomes were compared for their activity on selected cellulosic substrates. Interestingly, cellulosomes derived from cells grown on lignocellulosic biomass showed no advantage in hydrolyzing the original carbon source used for their production. Instead, microcrystalline cellulose- and glucose-derived cellulosomes were equal or superior in their capacity to deconstruct lignocellulosic biomass. Mass spectrometry analysis revealed differential composition of catalytic and structural subunits (scaffoldins) in the different cellulosome samples. The most abundant catalytic subunits in all cellulosome types include Cel48S, Cel9K, Cel9Q, Cel9R, and Cel5G. Microcrystalline cellulose- and glucose-derived cellulosome samples showed higher endoglucanase-to-exoglucanase ratios and higher catalytic subunit-per-scaffoldin ratios compared to lignocellulose-derived cellulosome types. The results reported here highlight the finding that cellulosomes derived from cells grown on glucose

  9. Pest Control in Corn and Soybeans: Weeds - Insects - Diseases.

    Science.gov (United States)

    Doersch, R. E.; And Others

    This document gives the characteristics and application rates for herbicides used to control annual weeds in corn, annual and perennial broadleaf weeds in corn, quackgrass and yellow nutsedge in corn, and annual weeds in soybeans. It also gives insecticide use information for corn and soybeans. A brief discussion of disease control in corn and…

  10. 7 CFR 810.401 - Definition of corn.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Definition of corn. 810.401 Section 810.401... GRAIN United States Standards for Corn Terms Defined § 810.401 Definition of corn. Grain that consists of 50 percent or more of whole kernels of shelled dent corn and/or shelled flint corn (Zea mays L...

  11. 21 CFR 137.215 - Yellow corn flour.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Yellow corn flour. 137.215 Section 137.215 Food... Flours and Related Products § 137.215 Yellow corn flour. Yellow corn flour conforms to the definition and standard of identity prescribed by § 137.211 for white corn flour except that cleaned yellow corn is used...

  12. 21 CFR 137.265 - Degerminated white corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Degerminated white corn meal. 137.265 Section 137... Cereal Flours and Related Products § 137.265 Degerminated white corn meal. (a) Degerminated white corn meal, degermed white corn meal, is the food prepared by grinding cleaned white corn and removing bran...

  13. Effect of irradiation on sweet corn preservation

    International Nuclear Information System (INIS)

    Fu Junjie

    2002-01-01

    60 Co γ-ray was used to irradiate newly-harvested sweet corn and the results showed that the effects of irradiation on soluble solids, sucrose, starch and total sugar were not significant. The viscosity of starch decreased with the increasing of irradiation dose. The preservation duration of irradiated sweet corn was 7 days longer than that of CK, and the sweet, smell, taste of sweet corn had no abnormal change

  14. Bio-Oil Production from Fast Pyrolysis of Corn Wastes and Eucalyptus Wood in a Fluidized Bed Reactor

    Directory of Open Access Journals (Sweden)

    M.A Ebrahimi-Nik

    2014-09-01

    Full Text Available Fast pyrolysis is an attractive technology for biomass conversion, from which bio-oil is the preferred product with a great potential for use in industry and transport. Corn wastes (cob and stover and eucalyptus wood are widely being produced throughout the world. In this study, fast pyrolysis of these two materials were examined under the temperature of 500 °C; career gas flow rate of 660 l h-1; particle size of 1-2 mm; 80 and 110 g h-1 of feed rate. The experiments were carried out in a continuous fluidized bed reactor. Pyrolysis vapor was condensed in 3 cooling traps (15, 0 and -40 °C plus an electrostatic one. Eucalyptus wood was pyrolyised to 12.4, 61.4, and 26.2 percent of bio-char, bio-oil and gas, respectively while these figures were as 20.15, 49.9, and 29.95 for corn wastes. In all experiments, the bio-oil obtained from electrostatic trap was a dark brown and highly viscose liquid.

  15. Cornelis den Hartog: an outstanding aquatic ecologist

    NARCIS (Netherlands)

    Velde, van der G.; Brock, T.C.M.; Kempers, A.J.

    1996-01-01

    A survey is given of the work and life of Cornelis den Hartog up to the date in 1996 on which he retired from his position as a professor at the University of Nijmegen. Cornelis (Kees) den Hartog made important contributions to aquatic ecology in the widest sense, e.G. On brackish water typology,

  16. Climate forecasts for corn producer decision making

    Science.gov (United States)

    Corn is the most widely grown crop in the Americas, with annual production in the United States of approximately 332 million metric tons. Improved climate forecasts, together with climate-related decision tools for corn producers based on these improved forecasts, could substantially reduce uncertai...

  17. Analysis of xanthophylls in corn by HPLC.

    Science.gov (United States)

    Moros, E E; Darnoko, D; Cheryan, M; Perkins, E G; Jerrell, J

    2002-10-09

    An HPLC method was developed using the C-30 carotenoid column to separate and identify the major xanthophylls in corn (lutein, zeaxanthin, and beta-cryptoxanthin). A photodiode array detector and a mobile phase consisting of methyl tert-butyl ether/methanol/water was used. All three xanthophylls eluted in less than 25 min. Yellow dent corn had a total xanthophyll content of 21.97 microg/g with lutein content of 15.7 microg/g, zeaxanthin content of 5.7 microg/g, and beta-cryptoxanthin of 0.57 microg/g. Commercial corn gluten meal had a 7 times higher concentration of xanthophylls (145 microg/g), and deoiled corn contained 18 microg/g, indicating that the xanthophylls are probably bound to the zein fraction of corn proteins.

  18. Compositional variability of nutrients and phytochemicals in corn after processing.

    Science.gov (United States)

    Prasanthi, P S; Naveena, N; Vishnuvardhana Rao, M; Bhaskarachary, K

    2017-04-01

    The result of various process strategies on the nutrient and phytochemical composition of corn samples were studied. Fresh and cooked baby corn, sweet corn, dent corn and industrially processed and cooked popcorn, corn grits, corn flour and corn flakes were analysed for the determination of proximate, minerals, xanthophylls and phenolic acids content. This study revealed that the proximate composition of popcorn is high compared to the other corn products analyzed while the mineral composition of these maize products showed higher concentration of magnesium, phosphorus, potassium and low concentration of calcium, manganese, zinc, iron, copper, and sodium. Popcorn was high in iron, zinc, copper, manganese, sodium, magnesium and phosphorus. The xanthophylls lutein and zeaxanthin were predominant in the dent corn and the total polyphenolic content was highest in dent corn while the phenolic acids distribution was variable in different corn products. This study showed preparation and processing brought significant reduction of xanthophylls and polyphenols.

  19. 21 CFR 137.285 - Degerminated yellow corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Degerminated yellow corn meal. 137.285 Section 137... Cereal Flours and Related Products § 137.285 Degerminated yellow corn meal. Degerminated yellow corn meal, degermed yellow corn meal, conforms to the definition and standard of identity prescribed by § 137.265 for...

  20. 21 CFR 137.280 - Bolted yellow corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Bolted yellow corn meal. 137.280 Section 137.280... Flours and Related Products § 137.280 Bolted yellow corn meal. Bolted yellow corn meal conforms to the definition and standard of identity prescribed by § 137.255 for bolted white corn meal except that cleaned...

  1. Possible causes of dry pea synergy to corn

    Science.gov (United States)

    Dry pea improves corn yield and tolerance to weed interference compared with soybean, spring wheat, or canola as preceding crops. To understand this synergy between dry pea and corn, we examined growth and nutrient concentration of corn following dry pea or soybean in sequence. Each corn plot was ...

  2. Aflatoxin contamination of developing corn kernels.

    Science.gov (United States)

    Amer, M A

    2005-01-01

    Preharvest of corn and its contamination with aflatoxin is a serious problem. Some environmental and cultural factors responsible for infection and subsequent aflatoxin production were investigated in this study. Stage of growth and location of kernels on corn ears were found to be one of the important factors in the process of kernel infection with A. flavus & A. parasiticus. The results showed positive correlation between the stage of growth and kernel infection. Treatment of corn with aflatoxin reduced germination, protein and total nitrogen contents. Total and reducing soluble sugar was increase in corn kernels as response to infection. Sucrose and protein content were reduced in case of both pathogens. Shoot system length, seeding fresh weigh and seedling dry weigh was also affected. Both pathogens induced reduction of starch content. Healthy corn seedlings treated with aflatoxin solution were badly affected. Their leaves became yellow then, turned brown with further incubation. Moreover, their total chlorophyll and protein contents showed pronounced decrease. On the other hand, total phenolic compounds were increased. Histopathological studies indicated that A. flavus & A. parasiticus could colonize corn silks and invade developing kernels. Germination of A. flavus spores was occurred and hyphae spread rapidly across the silk, producing extensive growth and lateral branching. Conidiophores and conidia had formed in and on the corn silk. Temperature and relative humidity greatly influenced the growth of A. flavus & A. parasiticus and aflatoxin production.

  3. Deposition of insecticides on corn silks applied at high and low spray rates for control of corn earworm

    Science.gov (United States)

    Corn earworm is a major pest of sweet corn, especially when grown organically. Aerial application of insecticides is important for both conventionally- and organically-grown sweet corn production as sweet corn is frequently irrigated to assure return on investment given the high production costs. ...

  4. 21 CFR 137.275 - Yellow corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Yellow corn meal. 137.275 Section 137.275 Food and... Related Products § 137.275 Yellow corn meal. Yellow corn meal conforms to the definition and standard of identity prescribed by § 137.250 for white corn meal except that cleaned yellow corn is used instead of...

  5. Enhancement of enzymatic hydrolysis of wheat straw by gamma irradiation–alkaline pretreatment

    International Nuclear Information System (INIS)

    Yin, Yanan; Wang, Jianlong

    2016-01-01

    Pretreatment of wheat straw with gamma irradiation and NaOH was performed to enhance the enzymatic hydrolysis of wheat straw for production of reducing sugar. The results showed that the irradiation of wheat straw at 50 kGy decreased the yield of reducing sugar, however, the reducing sugar yield increased with increasing dose from 50 kGy to 400 kGy. The irradiation of wheat straw at 100 kGy can significantly decrease NaOH consumption and treatment time. The reducing sugar yield could reach 72.67% after irradiation at 100 kGy and 2% NaOH treatment for 1 h. The combined pretreatment of wheat straw by gamma radiation and NaOH immersion can increase the solubilization of hemicellulose and lignin as well as the accessible surface area for enzyme molecules. - Highlights: • Pretreatment of wheat straw by gamma radiation and NaOH was investigated. • Irradiation pretreatment can significantly decrease NaOH consumption. • Reducing sugar yield reached 72.67% at 100 kGy and 2% NaOH treatment for 1 h.

  6. Characteristics and Gel Properties of Gelatin from Goat Skin as Influenced by Alkaline-pretreatment Conditions

    Directory of Open Access Journals (Sweden)

    Sulaiman Mad-Ali

    2016-06-01

    Full Text Available Characteristics and properties of gelatin from goat skin pretreated with NaOH solutions (0.50 and 0.75 M for various times (1 to 4 days were investigated. All gelatins contained α-chains as the predominant component, followed by β-chain. Gelling and melting temperatures of those gelatins were 23.02°C to 24.16°C and 33.07°C to 34.51°C, respectively. Gel strength of gelatins increased as NaOH concentration and pretreatment time increased (p<0.05. Pretreatment for a longer time yielded gelatin with a decrease in L*-value but an increase in b*-value. Pretreatment of goat skin using 0.75 M NaOH for 2 days rendered the highest yield (15.95%, wet weight basis as well as high gel strength (222.42 g, which was higher than bovine gelatin (199.15 g. Gelatin obtained had the imino acid content of 226 residues/1,000 residues and the gelatin gel had a fine and ordered structure. Therefore, goat skin gelatin could be used as a potential replacer of commercial gelatin.

  7. Uptake and distribution of cadmium in corn

    International Nuclear Information System (INIS)

    Peel, J.W.; Vetter, R.J.; Christian, J.E.; Kessler, W.V.; McFee, W.W.

    1978-01-01

    The uptake and distribution of cadmium in corn (Zea mays) treated at various time intervals after planting and sampled at various times after treatment were measured. Cadmium was found to accumulate in all parts sampled. As shown in field studies, stems and leaves generally concentrated more cadmium than did husks, cobs, kernels, silks, or tassels. Samples of stems and leaves from corn treated 23 days after planting and sampled 5 days later exhibited higher concentrations of cadmium than samples taken 25, 45, 65, or 85 days after treatment. Concentrations generally decreased with time. Greenhouse studies showed that corn exposed to cadmium for the longest period of time accumulated the greatest total cadmium. The highest cadmium concentrations were found in the base or lowest leaves sampled 45 days after planting; this suggests a useful technique for quick screening corn crops for cadmium pollution

  8. Enzymatic hydrolysis of corn bran arabinoxylan

    DEFF Research Database (Denmark)

    Agger, Jane

    as a model substrate because it represents a readily available agroindustrial side product with upgrading potentials. Corn bran originates from the wet-milling process in corn starch processing, is the outmost layers of the corn kernel and is particularly rich in pentose monosaccharides comprising the major...... in a complex and ridig cell wall structure. This thesis contains a thorough examination of the monosaccharide and structural composition of corn bran, which is used to assess and apply the relevant mono component enzyme preparations. In this way, the aim is to obtain the most effective minimal enzymatic......, especially with respect to xylose and glucose release, but vast amounts of the valuable monosaccharides are lost during this pretreatment and this is especially evident for arabinose. From a scientific point of view acid catalysed pretreatment renders the substrate in a state of disruption where assessment...

  9. Renewable corn-ethanol and energy security

    International Nuclear Information System (INIS)

    Eaves, James

    2007-01-01

    Though corn-ethanol is promoted as renewable, models of the production process assume fossil fuel inputs. Moreover, ethanol is promoted as a means of increasing energy security, but there is little discussion of the dependability of its supply. This study investigates the sensibility of promoting corn-ethanol as an automobile fuel, assuming a fully renewable production process. We then use historical data to estimate the supply risk of ethanol relative to imported petroleum. We find that devoting 100% of US corn to ethanol would displace 3.5% of gasoline consumption and the annual supply of the ethanol would be inherently more risky than that of imported oil. Finally, because large temperature increases can simultaneously increase fuel demand and the cost of growing corn, the supply responses of ethanol producers to temperature-induced demand shocks would likely be weaker than those of gasoline producers. (author)

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

    OpenAIRE

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

    2016-01-01

    Background 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 ...

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

    Science.gov (United States)

    2002-06-01

    is pumped from the blowdown tank into the hydrolyzate mixing tank (T-205) and mixed with recycled filtrate liquor (from tank T-213) to reduce the...slurrying tank (T-232) where it is mixed with conditioned hydrolyzate liquor and additional recycle water. Product liquor to be conditioned is pumped from...lignin-derived compounds. These reactions detoxify the hydrolyzate and the detoxification is more efficient at higher pH. Investigations into the

  12. ENZYMATIC HYDROLYSIS LIGNIN DERIVED FROM CORN STOVER AS AN INTRINSTIC BINDER FOR BIO-COMPOSITES MANUFACTURE: EFFECT OF FIBER MOISTURE CONTENT AND PRESSING TEMPERATURE ON BOARDS’ PROPERTIES

    Directory of Open Access Journals (Sweden)

    Guanben Du

    2011-02-01

    Full Text Available Binderless fiberboards from enzymatic hydrolysis lignin (EHL and cotton stalk fibers were prepared under various manufacturing conditions, and their physico-mechanical properties were evaluated. Full factorial experimental design was used to assess the effect of fiber moisture content and pressing temperature on boards’ properties. In addition, differential scanning calorimetry (DSC was used to obtain the glass transition temperature (Tg of EHL. We found that both fiber moisture content and pressing temperature had significant effects on binderless fiberboards’ properties. High fiber moisture content and pressing temperature are suggested to contribute to the self-bonding improvement among fibers with lignin-rich surface mainly by thermal softening enzymatic hydrolysis lignin. In this experiment, the optimized pressing temperature applied in binderless fiberboard production should be as high as 190°C in accordance with the EHL Tg value of 189.4°C, and the fiber moisture content should be limited to less than 20% with a higher board density of 950 kg/m3 to avoid the delamination of boards during hot pressing.

  13. Techno-Economic Analysis of Bioethanol Production from Lignocellulosic Biomass in China: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover

    Directory of Open Access Journals (Sweden)

    Lili Zhao

    2015-05-01

    Full Text Available Lignocellulosic biomass-based ethanol is categorized as 2nd generation bioethanol in the advanced biofuel portfolio. To make sound incentive policy proposals for the Chinese government and to develop guidance for research and development and industrialization of the technology, the paper reports careful techno-economic and sensitivity analyses performed to estimate the current competitiveness of the bioethanol and identify key components which have the greatest impact on its plant-gate price (PGP. Two models were developed for the research, including the Bioethanol PGP Assessment Model (BPAM and the Feedstock Cost Estimation Model (FCEM. Results show that the PGP of the bioethanol ranges $4.68–$6.05/gal (9,550–12,356 yuan/t. The key components that contribute most to bioethanol PGP include the conversion rate of cellulose to glucose, the ratio of five-carbon sugars converted to ethanol, feedstock cost, and enzyme loading, etc. Lignocellulosic ethanol is currently unable to compete with fossil gasoline, therefore incentive policies are necessary to promote its development. It is suggested that the consumption tax be exempted, the value added tax (VAT be refunded upon collection, and feed-in tariff for excess electricity (byproduct be implemented to facilitate the industrialization of the technology. A minimum direct subsidy of $1.20/gal EtOH (2,500 yuan/t EtOH is also proposed for consideration.

  14. 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...

  15. Techno-Economic Analysis of Bioethanol Production from Lignocellulosic Biomass in China: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover

    OpenAIRE

    Zhao, Lili; Zhang, Xiliang; Xu, Jie; Ou, Xunmin; Chang, Shiyan; Wu, Maorong

    2015-01-01

    Lignocellulosic biomass-based ethanol is categorized as 2 nd generation bioethanol in the advanced biofuel portfolio. To make sound incentive policy proposals for the Chinese government and to develop guidance for research and development and industrialization of the technology, the paper reports careful techno-economic and sensitivity analyses performed to estimate the current competitiveness of the bioethanol and identify key components which have the greatest impact on its plant-gate price...

  16. A time course analysis of the extracellular proteome of Aspergillus nidulans growing on sorghum stover

    Directory of Open Access Journals (Sweden)

    Saykhedkar Sayali

    2012-07-01

    Full Text Available Abstract Background Fungi are important players in the turnover of plant biomass because they produce a broad range of degradative enzymes. Aspergillus nidulans, a well-studied saprophyte and close homologue to industrially important species such as A. niger and A. oryzae, was selected for this study. Results A. nidulans was grown on sorghum stover under solid-state culture conditions for 1, 2, 3, 5, 7 and 14 days. Based on analysis of chitin content, A. nidulans grew to be 4-5% of the total biomass in the culture after 2 days and then maintained a steady state of 4% of the total biomass for the next 12 days. A hyphal mat developed on the surface of the sorghum by day one and as seen by scanning electron microscopy the hyphae enmeshed the sorghum particles by day 5. After 14 days hyphae had penetrated the entire sorghum slurry. Analysis (1-D PAGE LC-MS/MS of the secretome of A. nidulans, and analysis of the breakdown products from the sorghum stover showed a wide range of enzymes secreted. A total of 294 extracellular proteins were identified with hemicellulases, cellulases, polygalacturonases, chitinases, esterases and lipases predominating the secretome. Time course analysis revealed a total of 196, 166, 172 and 182 proteins on day 1, 3, 7 and 14 respectively. The fungus used 20% of the xylan and cellulose by day 7 and 30% by day 14. Cellobiose dehydrogenase, feruloyl esterases, and CAZy family 61 endoglucanases, all of which are thought to reduce the recalcitrance of biomass to hydrolysis, were found in high abundance. Conclusions Our results show that A. nidulans secretes a wide array of enzymes to degrade the major polysaccharides and lipids (but probably not lignin by 1 day of growth on sorghum. The data suggests simultaneous breakdown of hemicellulose, cellulose and pectin. Despite secretion of most of the enzymes on day 1, changes in the relative abundances of enzymes over the time course indicates that the set of enzymes

  17. Corn silage from corn treated with foliar fungicide and performance of Holstein cows.

    Science.gov (United States)

    Haerr, K J; Lopes, N M; Pereira, M N; Fellows, G M; Cardoso, F C

    2015-12-01

    Foliar fungicide application to corn plants is used in corn aimed for corn silage in the dairy industry, but questions regarding frequency of application and its effect on corn silage quality and feed conversion when fed to dairy cows remain prevalent. The objective of this study was to evaluate the effects of various foliar fungicide applications to corn on dry matter intake (DMI), milk production, and milk composition when fed to dairy cows. Sixty-four Holstein cows with parity 2.5±1.5, 653±80kg of body weight, and 161±51d in milk were blocked and randomly assigned to 1 of 4 corn silage treatments (total mixed ration with 35% of the dry matter as corn silage). Treatments were as follows: control (CON), corn silage with no applications of foliar fungicide; treatment 1 (1X), corn silage from corn that received 1 application of pyraclostrobin (PYR) foliar fungicide (Headline; BASF Corp.) at corn vegetative stage 5; treatment 2 (2X), corn silage from corn that received the same application as 1X plus another application of a mixture of PYR and metconazole (Headline AMP; BASF Corp.) at corn reproductive stage 1 ("silking"); and treatment 3 (3X), corn silage from corn that received the same applications as 2X as well as a third application of PYR and metconazole at reproductive stage 3 ("milky kernel"). Corn was harvested at about 32% dry matter and 3/4 milk line stage of kernel development and ensiled for 200d. Treatments were fed to cows for 5wk, with the last week being used for statistical inferences. Week -1 was used as a covariate in the statistical analysis. Dry matter intake tended to be lower for cows fed corn silage treated with fungicide than CON (23.8, 23.0, 19.5, and 21.3kg for CON, 1X, 2X, and 3X, respectively). A linear treatment effect for DMI was observed, with DMI decreasing as foliar fungicide applications increased. Treatments CON, 1X, 2X, and 3X did not differ for milk yield (34.5, 34.5, 34.2, and 34.4kg/d, respectively); however, a trend for

  18. ELASTICITY OF CORN PRICE TRANSMISION AND ITS IMPLICATION TO FARMERS

    Directory of Open Access Journals (Sweden)

    Ahmad Muslim

    2011-09-01

    Full Text Available Corn has important roles to Indonesian economy both for staple foods and for price transmission to other products. The high domestic demand for corn compared to its domestic production has made corn imports continue to grow. This research is aimed to know the elasticity of price transmission and its implication to corn’s farmers. The results of analysis show that corn price transmission is inelastic. The coefficient shows that corn market is oligopsony under the imperfect competition market. To help the corn farmers, the government has to provide fertilizer subsidy and farm credit with low interest rates, as well as impose import tariff on corn. Keywords: Corn, Elasticity of price transmission, oligopsony, imperfect competition marketJEL classification numbers: Q00, Q12, Q18

  19. Protective effects of flavonoids from corn silk on oxidative stress ...

    African Journals Online (AJOL)

    Protective effects of flavonoids from corn silk on oxidative stress induced by ... The present study aims at exploring the effects of flavonoids from corn silk (FCS) on oxidative stress induced by exhaustive exercise in mice. ... from 32 Countries:.

  20. Host Recognition Responses of Western (Family: Chrysomelidae) Corn Rootworm Larvae to RNA Interference and Bt Corn.

    Science.gov (United States)

    Zukoff, Sarah N; Zukoff, Anthony L

    2017-01-01

    Western corn rootworm Diabrotica virgifera virgifera LeConte is an important pest of corn whose larvae exhibit particular quantifiable patterns of locomotion after exposure to, and removal from, host roots and nonhost roots. Using EthoVision software, the behavior and locomotion of the western corn rootworm larvae was analyzed to determine the level of host recognition to germinated roots of differing corn hybrids containing either rootworm targeted Bt genes, RNA interference (RNAi) technology, the stack of both Bt and RNAi, or the isoline of these. The behavior of the rootworm larvae indicated a significant host preference response to all corn hybrids (with or without insecticidal traits) compared to the filter paper and oat roots. A weaker host response to the RNAi corn roots was observed in the susceptible larvae when compared to the resistant larvae, but not for the Bt + RNAi vector stack. Additionally, the resistant larvae demonstrated a weaker host response to the isoline corn roots when compared to the susceptible larvae. Although weaker, these host responses were significantly different from those observed in the negative controls, indicating that all hybrids tested do contain the contact cues necessary to elicit a host preference response by both Cry3Bb1-resistant and Cry3Bb1-susceptible larvae that would work to hinder resistance development in refuge in a bag fields. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  1. Corn Cultivation to Reduce the Mycotoxin Contamination

    Directory of Open Access Journals (Sweden)

    Yangseon Kim

    2017-09-01

    Full Text Available The effects of insecticide and fungicide treatment were investigated to reduce mycotoxin contamination of corn (Zea mays L. seeds. Deoxynivalenol and zearalenone contents were reduced in the treated seeds, but aflatoxin, ochratoxin A, fumonisin, and T-2 toxin were not effective by chemical treatments. The chemical treatment did not affect the growth of saprophyte, but inhibited the pathogenic fungi such as Fusarium verticillioides, F. graminearum and F. equiseti. Myotoxin contents at different harvesting time were compared. As the harvest time was delayed, both levels of deoxynivalenol and zearalenone and frequency of Fusarium spp. increased. However, the major nutrient contents of corn seeds were not affected by harvesting period. These results show that chemical treatments are necessary to reduce the fungal contamination of corn and harvest without delay is important as well.

  2. 21 CFR 137.255 - Bolted white corn meal.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Bolted white corn meal. 137.255 Section 137.255... Flours and Related Products § 137.255 Bolted white corn meal. (a) Bolted white corn meal is the food prepared by so grinding and sifting cleaned white corn that: (1) Its crude fiber content is less than 1.2...

  3. 21 CFR 137.260 - Enriched corn meals.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Enriched corn meals. 137.260 Section 137.260 Food... Flours and Related Products § 137.260 Enriched corn meals. (a) Enriched corn meals are the foods, each of which conforms to the definition and standard of identity prescribed for a kind of corn meal by §§ 137...

  4. Quantitative analysis of allantoin in Iranian corn silk

    OpenAIRE

    E. Khanpour*; M. Modarresi

    2017-01-01

    Background and objectives: Zea mays is cultivated in different parts of Iran and corn silk is used in traditional medicine. Allantoin is one of the major compounds in corn silk. The purpose of this research was the quantitatve analysis of allantoin in corn silks belonging to several regions of Iran. Methods: The samples of corn silk were prepared from three provinces of Iran (Kermanshah, Fars and Razavi Khorasan). The dried plant materials were infused in boiling distilled water with a temper...

  5. Influence of continuous cropping on corn and soybean pathogens

    OpenAIRE

    Ranzi, Camila; Camera, Juliane Nicolodi; Deuner, Carolina Cardoso

    2017-01-01

    ABSTRACT The objective of this study was to evaluate the influence of two tillage programs (conventional and no-tillage) and different rotations with soybeans and corn on the occurrence of Fusarium species. The work was conducted in the experimental field and Seed Laboratory at Iowa State University. The treatments were: tillage (no-tillage and conventional tillage), crop (corn and soybeans) and three different cropping sequences for corn and soybeans, respectively. Treatment with corn: (1) t...

  6. Hydrolysis of corn oil using subcritical water

    Directory of Open Access Journals (Sweden)

    Pinto Jair Sebastião S.

    2006-01-01

    Full Text Available This work presents the results of a study on the use of subcritical water as both solvent and reactant for the hydrolysis of corn oil without the use of acids or alkalis at temperatures of 150-280 degreesC. Corn oil hydrolysis leads to the formation of its respective fatty acids with the same efficiency of conventional methods. Fatty acids form an important group of products, which are used in a range of applications. The confirmation and identification of the hydrolysis products was done by HT-HRGC-FID and HRGC/MS.

  7. Corn residue utilization by livestock in the USA

    Science.gov (United States)

    Corn (Zea mays L.) residue grazing or harvest provides a simple and economical practice to integrate crops and livestock. Limited information is available on how widespread corn residue utilization is practiced by US producers. In 2010, the USDA-ERS surveyed producers from 19 states on corn grain ...

  8. 21 CFR 573.530 - Hydrogenated corn syrup.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Hydrogenated corn syrup. 573.530 Section 573.530... Additive Listing § 573.530 Hydrogenated corn syrup. (a) Identity. The product is produced by hydrogenation of corn syrup over a nickel catalyst. (b) Specifications. The product contains 70 percent...

  9. Corn Clubs: Building the Foundation for Agricultural and Extension Education

    Science.gov (United States)

    Uricchio, Cassandra; Moore, Gary; Coley, Michael

    2013-01-01

    Corn clubs played an important role in improving agriculture at the turn of the 20th century. Corn clubs were local organizations consisting of boys who cultivated corn on one acre of land under the supervision of a local club leader. The purpose of this historical research study was to document the organization, operation, and outcomes of corn…

  10. 7 CFR 407.11 - Group risk plan for corn.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Group risk plan for corn. 407.11 Section 407.11..., DEPARTMENT OF AGRICULTURE GROUP RISK PLAN OF INSURANCE REGULATIONS § 407.11 Group risk plan for corn. The provisions of the Group Risk Plan for Corn for the 2000 and succeeding crop years are as follows: 1...

  11. Visual responses of corn silk flies (Diptera: Ulidiidae)

    Science.gov (United States)

    Corn silk flies are major pests impacting fresh market sweet corn production in Florida and Georgia. Control depends solely on well-times applications of insecticides to protect corn ear development. Surveillance depends on visual inspection of ears with no effective trapping methods currently ava...

  12. Physicochemical and sensory qualities of spiced soy-corn milk ...

    African Journals Online (AJOL)

    Soy-corn milk type was produced from a blend of soybean milk and corn milk extract at a ratio of 3:1. The soy-corn milk type was spiced with ginger and garlic extract respectively to improve the taste. Total dissolved solid (TDS), total titrable acidity (TTA) specific gravity (SG), apparent colloidal stability, pH and sensory ...

  13. Determining the Feasibility of Yellow Corn Production in Mexico

    OpenAIRE

    Mejia, Maria; Peel, Derrell S.

    2009-01-01

    Mexico produces large quantities of white corn for human consumption. Yellow corn production, mostly used for feed, has increased lately. Driving factors include higher domestic demand (growing livestock industry) and greater international demand (ethanol industry). This study uses enterprise budgeting to determine the feasibility of producing yellow corn in Mexico.

  14. 21 CFR 73.315 - Corn endosperm oil.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Corn endosperm oil. 73.315 Section 73.315 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.315 Corn endosperm oil. (a) Identity. (1) The color additive corn endosperm oil is a reddish-brown liquid composed chiefly of glycerides, fatty acids, sitosterols...

  15. Intercropping of corn with cowpea and bean: Biomass yield and ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-11-19

    Nov 19, 2008 ... Hand weeding by hoe was done once when the corn was app. 20 cm in height. Plots were harvested at the doughy stage of corn, cutting mid-rows of plots in order to avoid border effects, by removing at 4-5 cm height on 9 Sept.,. 2004 and 12 Sept., 2005, respectively. Corn was harvested from the middle 5.

  16. Winter rye cover crop effect on corn seedling pathogens

    Science.gov (United States)

    Cover crops have been grown successfully in Iowa, but sometimes a cereal rye cover crop preceding corn can reduce corn yields. Our research examines the effect of a rye cover crop on infections of the succeeding corn crop by soil fungal pathogens. Plant measurements included: growth stage, height, r...

  17. Optimizing bio-physical conditions and pre-treatment options for breaking lignin barrier of maize stover feed using white rot fungi

    Directory of Open Access Journals (Sweden)

    Andrew M. Atuhaire

    2016-12-01

    Full Text Available The greatest limitation to utilization of maize stover by ruminants as a feed is the high concentration of lignin, which limits fibre digestibility. However, ruminants can effectively utilize maize stover if its nutritive value is improved using white rot fungal species. This study was designed to determine optimal bio-physical conditions for mycelial growth and select the most ideal fungal species and pre-treatment options for improving nutritive value of maize stover. Four popular edible Pleurotus fungal species (viz. Pleurotus florida, Pleurotus ostreatus, Pleurotus sajor caju and Pleurotus pulmonarius were subjected to varying temperatures, pH levels, hydrogen peroxide (H2O2 concentration and illumination to establish the extent of mycelial growth rate. Inclusion of H2O2 was used to determine optimal levels for preservation and prevention of contamination from other indigenous microbiota. Effects of pre-treatment options on chemical composition and nutritive value of maize stover were also examined. Mycelial growth rate of Pleurotus species on potato dextrose agar (PDA varied (P < 0.05 with temperature, pH level and H2O2 concentration following a quadratic trend. Optimal temperature, pH and H2O2 concentration for mycelial growth on PDA were 25 °C, 5 and 0.01 mL/L, respectively. Under the different bio-physical conditions, P. sajor caju had the highest mycelia density and growth rate. Chemical composition of solid-state fermented maize stover differed (P < 0.05 among the Pleurotus species. Maize stover fermented with P. sajor caju had the highest crude protein (CP of 86.6 g/kg DM, in-vitro dry matter digestibility (IVDMD of 731 g/kg DM, in-vitro organic matter digestibility (IVOMD of 670.4 g/kg DM and metabolizable energy (ME of 10.0 MJ/kg DM but with the lowest lignin (sa of 50 g/kg DM. At 25 °C, P. sajor caju had the highest mycelial growth rate on PDA and highest lignin (sa breakdown in the maize stover substrate. It was

  18. Henry Agard Wallace, the Iowa Corn Yield Tests, and the Adoption of Hybrid Corn

    OpenAIRE

    Richard C. Sutch

    2008-01-01

    This research report makes the following claims: 1] There was not an unambiguous economic advantage of hybrid corn over the open-pollinated varieties in 1936. 2] The early adoption of hybrid corn before 1937 can be better explained by a sustained propaganda campaign conducted by the U.S. Department of Agriculture at the direction of the Secretary of Agriculture, Henry Agard Wallace. The Department's campaign echoed that of the commercial seed companies. The most prominent hybrid seed company,...

  19. 21 CFR 184.1262 - Corn silk and corn silk extract.

    Science.gov (United States)

    2010-04-01

    ... specific limitations: Category of food Maximum level of use in food (as served) 1 Functional use Baked... chapter 10 Do. Soft candy, § 170.3(n)(38) of this chapter 20 Do. All other food categories 4 Do. 1 Parts... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Corn silk and corn silk extract. 184.1262 Section...

  20. experimental viscoelastic characterization of corn cob composites ...

    African Journals Online (AJOL)

    Dr Obe

    sufficient to represent the viscoelastic behavior of the corn cob. The effect of moisture content and rates of loading on the mechanical model determined were investigated. 1. ..... F = applied force or residual force σ. = contact stress .... J. Agric. Engineering. Res. 7(4):. 300-315. Journal of the British Society for. Research in ...

  1. Analysis of heavy metals in corn

    International Nuclear Information System (INIS)

    Enger, B.; Dirdal, B.; Paus, P.E.

    1979-03-01

    Methods for the analysis of metals in Norwegian corn types have been tested. The main emphasis is on atomic absorption spectroscopy, with both wet and dry ashing, but the results are compared with emission spectroscopy and neutron activation analysis. In the latter only instrumental analysis has been carried out, restricting the number of metals which could be analysed. (JIW)

  2. Producing ergosterol from corn straw hydrolysates using ...

    African Journals Online (AJOL)

    Ergosterol is an economically important metabolite produced by Saccharomyces cerevisiae. In this study, the production of ergosterol by the strain using corn straw as an inexpensive carbon source was investigated. The total yield of ergosterol was determined by both the biomass and ergosterol content in yeast cells which ...

  3. Experimental Viscoelastic Characterization of Corn Cob Composited ...

    African Journals Online (AJOL)

    The nature of viscoelasticity in biomateria1s and the techniques for characterizing their rheological properties were reviewed. Relaxation tests were performed with cylindrical samples of corn cob composites which were initially subjected to radial compression. It was found that a Maxwell model composed of two simple ...

  4. 21 CFR 155.130 - Canned corn.

    Science.gov (United States)

    2010-04-01

    ... sweet corn packed with a suitable liquid packing medium which may include water and the creamy component... as specified in paragraph (a)(2) of this section. (ii) The words “vacuum pack” or “vacuum packed... found, less the weight of the sieve, as the drained weight. Dry and weigh the empty container and...

  5. Relationship between processing score and kernel-fraction particle size in whole-plant corn silage.

    Science.gov (United States)

    Dias Junior, G S; Ferraretto, L F; Salvati, G G S; de Resende, L C; Hoffman, P C; Pereira, M N; Shaver, R D

    2016-04-01

    Kernel processing increases starch digestibility in whole-plant corn silage (WPCS). Corn silage processing score (CSPS), the percentage of starch passing through a 4.75-mm sieve, is widely used to assess degree of kernel breakage in WPCS. However, the geometric mean particle size (GMPS) of the kernel-fraction that passes through the 4.75-mm sieve has not been well described. Therefore, the objectives of this study were (1) to evaluate particle size distribution and digestibility of kernels cut in varied particle sizes; (2) to propose a method to measure GMPS in WPCS kernels; and (3) to evaluate the relationship between CSPS and GMPS of the kernel fraction in WPCS. Composite samples of unfermented, dried kernels from 110 corn hybrids commonly used for silage production were kept whole (WH) or manually cut in 2, 4, 8, 16, 32 or 64 pieces (2P, 4P, 8P, 16P, 32P, and 64P, respectively). Dry sieving to determine GMPS, surface area, and particle size distribution using 9 sieves with nominal square apertures of 9.50, 6.70, 4.75, 3.35, 2.36, 1.70, 1.18, and 0.59 mm and pan, as well as ruminal in situ dry matter (DM) digestibilities were performed for each kernel particle number treatment. Incubation times were 0, 3, 6, 12, and 24 h. The ruminal in situ DM disappearance of unfermented kernels increased with the reduction in particle size of corn kernels. Kernels kept whole had the lowest ruminal DM disappearance for all time points with maximum DM disappearance of 6.9% at 24 h and the greatest disappearance was observed for 64P, followed by 32P and 16P. Samples of WPCS (n=80) from 3 studies representing varied theoretical length of cut settings and processor types and settings were also evaluated. Each WPCS sample was divided in 2 and then dried at 60 °C for 48 h. The CSPS was determined in duplicate on 1 of the split samples, whereas on the other split sample the kernel and stover fractions were separated using a hydrodynamic separation procedure. After separation, the

  6. 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.

  7. Cowpea (Vigna unguiculata L. Walp) and groundnut (Arachis hypogea L.) haulms as supplements to sorghum (Sorghum bicolor L. Moench) stover : intake, digestibility and optimum feeding levels

    NARCIS (Netherlands)

    Savadogo, M.; Zemmelink, G.; Nianogo, A.J.; Keulen, van H.

    2000-01-01

    Two feeding trials were conducted to study the combined effects of (i) varying degrees of selective consumption and (ii) supplementation with cowpea (Trail 1) or groundnut haulms (Trial 2), on intake of organic matter (IOM) from sorghum stover, and total intake of digestible organic matter (IDOM).

  8. Corn Residue Use by Livestock in the United States

    Directory of Open Access Journals (Sweden)

    Marty R. Schmer

    2017-01-01

    Full Text Available Corn ( L. residue grazing or harvest provides a simple and economical practice to integrate crops and livestock, but limited information is available on how widespread corn residue utilization is practiced by US producers. In 2010, the USDA Economic Research Service surveyed producers from 19 states on corn grain and residue management practices. Total corn residue grazed or harvested was 4.87 million ha. Approximately 4.06 million ha was grazed by 11.7 million livestock (primarily cattle in 2010. The majority of grazed corn residue occurred in Nebraska (1.91 million ha, Iowa (385,000 ha, South Dakota (361,000 ha, and Kansas (344,000 ha. Average grazing days ranged from 10 to 73 d (mean = 40 d. Corn residue harvests predominantly occurred in the central and northern Corn Belt, with an estimated 2.9 Tg of corn residue harvested across the 19 states. This survey highlights the importance of corn residue for US livestock, particularly in the western Corn Belt.

  9. Production of bioethanol from corn meal hydrolyzates

    Energy Technology Data Exchange (ETDEWEB)

    Ljiljana Mojovic; Svetlana Nikolic; Marica Rakin; Maja Vukasinovic [University of Belgrade, Belgrade (Serbia and Montenegro). Faculty of Technology and Metallurgy, Department of Biochemical Engineering and Biotechnology

    2006-09-15

    The two-step enzymatic hydrolysis of corn meal by commercially available {alpha}-amylase and glucoamylase and further ethanol fermentation of the obtained hydrolyzates by Saccharomyces cerevisiae yeast was studied. The conditions of starch hydrolysis such as substrate and enzyme concentration and the time required for enzymatic action were optimized taking into account both the effects of hydrolysis and ethanol fermentation. The corn meal hydrolyzates obtained were good substrates for ethanol fermentation by S. cerevisiae. The yield of ethanol of more than 80% (w/w) of the theoretical was achieved with a satisfactory volumetric productivity P (g/l h). No shortage of fermentable sugars was observed during simultaneous hydrolysis and fermentation. In this process, the savings in energy by carrying out the saccharification step at lower temperature (32{sup o}C) could be realized, as well as a reduction of the process time for 4 h. 31 refs., 5 figs., 2 tabs.

  10. Irish Corned Beef: A Culinary History

    OpenAIRE

    Mac Con Iomaire, Máirtín; Gallagher, Pádraic Óg

    2011-01-01

    This article proposes that a better knowledge of culinary history enriches all culinary stakeholders. The article will discuss the origins and history of corned beef in Irish cuisine and culture. It outlines how cattle have been central to the ancient Irish way of life for centuries, but were cherished more for their milk than their meat. In the early modern period, with the decline in the power of the Gaelic lords, cattle became and economic commodity that was exported to England. The Cattle...

  11. Comparison of amino acid digestibility coefficients for corn, corn gluten meal, and corn distillers dried grains with solubles (DDGS) among three different bioassays

    Science.gov (United States)

    The objective of this study was to determine standardized AA digestibility of corn, corn gluten meal (CGM) and three distillers dried grains with solubles (DDGS) using the precision-fed cecectomized rooster assay (PFR), the standardized ileal AA broiler chicken assay (SIAAD), and a newly developed p...

  12. Asian corn borer (ACB) and non-ACB pests in GM corn (Zea mays L.) in the Philippines.

    Science.gov (United States)

    Afidchao, Miladis M; Musters, C J M; de Snoo, Geert R

    2013-07-01

    The Asian corn borer (ACB), Ostrinia furnacalis (Guenée), has become the most damaging pest in corn in south-east Asia. Corn farmers in the Philippines have incurred great yield losses in the past decades because of ACB infestation. Bacillus thuringiensis (Bt) and Bt herbicide-tolerant (BtHT) corns have been developed to reduce borer attacks worldwide. This study assessed the extent of ACB and non-ACB pest infestations in both GM and non-GM corn in Isabela Province, the Philippines. Specific aims were to reinvestigate the efficacy of Bt corn in controlling ACB, to evaluate what parts of Bt corn plants are susceptible to ACB, to monitor the potential development of ACB resistance and to evaluate whether secondary pests dominate in an ACB-free Bt corn environment. The study involved preparatory interviews with farmers, site selection, field scouting and visual inspection of 200 plants along 200 m transect lines through 198 cornfields. Bt corn can efficiently reduce the ACB pest problem and reduce borer damage by 44%, to damage levels in Bt and BtHT corn of 6.8 and 7% respectively. The leaves of Bt corn were more susceptible, while cobs of Bt corn were less affected by ACB. Non-ACB pests were common in Bt toxin-free cornfields and reduced in non-GM cornfields where ACB was abundant. No secondary pest outbreaks were found in ACB-free Bt cornfields. Bt and BtHT corn hybrids containing the Cry1Ab protein performed well in Isabela Province. Reduced cob damage by ACB on Bt fields could mean smaller economic losses even with ACB infestation. The occurrence of ACB in Bt and BtHT cornfields, although at a moderate and insignificant level, could imply the potential development of resistance to Bt toxin. © 2012 Society of Chemical Industry.

  13. Cellulose conversion of corn pericarp without pretreatment.

    Science.gov (United States)

    Kim, Daehwan; Orrego, David; Ximenes, Eduardo A; Ladisch, Michael R

    2017-12-01

    We report enzyme hydrolysis of cellulose in unpretreated pericarp at a cellulase loading of 0.25FPU/g pericarp solids using a phenol tolerant Aspergillus niger pectinase preparation. The overall protein added was 5mg/g and gave 98% cellulose conversion in 72h. However, for double the amount of enzyme from Trichoderma reesei, which is significantly less tolerant to phenols, conversion was only 16%. The key to achieving high conversion without pretreatment is combining phenol inhibition-resistant enzymes (such as from A. niger) with unground pericarp from which release of phenols is minimal. Size reduction of the pericarp, which is typically carried out in a corn-to-ethanol process, where corn is first ground to a fine powder, causes release of highly inhibitory phenols that interfere with cellulase enzyme activity. This work demonstrates hydrolysis without pretreatment of large particulate pericarp is a viable pathway for directly producing cellulose ethanol in corn ethanol plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. ECOLOGICAL FOOTPRINT ANALYSIS OF CANNED SWEET CORN

    Directory of Open Access Journals (Sweden)

    Phairat Usubharatana

    2016-07-01

    Full Text Available There has been a notable increase in both consumer knowledge and awareness regarding the ecological benefits of green products and services. Manufacturers now pay more attention to green, environmentally friendly production processes. Two significant tools that can facilitate such a goal are life cycle assessment (LCA and ecological footprint (EF. This study aimed to analyse and determine the damage to the environment, focusing on the canned fruit and vegetable processing. Canned sweet corn (340 g was selected for the case study. All inputs and outputs associated with the product system boundary were collected through field surveys. The acquired inventory was then analysed and evaluated using both LCA and EF methodology. The results were converted into an area of biologically productive land and presented as global hectares (gha. The ecological footprint of one can of sweet corn was calculated as 6.51E-04 gha. The three factors with the highest impact on ecological footprint value were the corn kernels used in the process, the packaging and steam, equivalent to 2.93E-04 gha, 1.19E-04 gha and 1.17E-04 gha respectively. To promote the sustainable development, the company should develop new technology or utilize better management techniques to reduce the ecological footprint of canned food production.

  15. The improvement of corn starch isolation process by gamma irradiation

    International Nuclear Information System (INIS)

    Byun, M.W.; Kang, I.J.; Kwon, J.H.; Lee, S.J.; Kim, S.K.

    1995-01-01

    Gamma irradiation was applied to non-glutinous and glutinous corns for improving starch isolation process. No significant changes in proximate composition of corn grains were observed by gamma irradiation. Irradiation at 1 and 5 kGy was effective for sterilizing all contaminated microorganisms of non-glutinous and glutinous corns, respectively. The moisture-uptake rate constants were increased in proportional to the steeping temperature and applied irradiation dose level. The irradiation efficacy on water absorption properties was also recognized in the corns stored for six months at room temperature. The combined use of gamma irradiation with sulfur dioxide solution was very effective for reducing steeping time. The starch yield gradually increased as irradiation dose levels increased. At 2 kGy, the sarch yield of non-glutinous and glutinous corns increased by 38% and 27%, respectively. No significant difference in Hunter's color value was observed between the starches isolated from nonirradiated and irradiated corn grains

  16. The use of corn (ZEA MAYS) biomass in drying process

    International Nuclear Information System (INIS)

    Kricka, T.; Pliestic, S.

    1996-01-01

    The most important agricultural crop in the world, besides wheat and rice is corn. In the last 10 years, Republic of Croatia has produced about 2000000 tons of corn. Most of that is used for food and feed and for seed production and it is 1000000 tons in quantity. This quantity demands between 35000 to 40000 tons of oil. For the reason, this paper describes the possibilities of the substitution of oil with corn biomass after harvesting. (author)

  17. The effects of corn silk on glycaemic metabolism

    OpenAIRE

    Han Linna; Liu Tongjun; Guo Jianyou; Liu Yongmei

    2009-01-01

    Abstract Background Corn silk contains proteins, vitamins, carbohydrates, Ca, K, Mg and Na salts, fixed and volatile oils, steroids such as sitosterol and stigmasterol, alkaloids, saponins, tannins, and flavonoids. Base on folk remedies, corn silk has been used as an oral antidiabetic agent in China for decades. However, the hypoglycemic activity of it has not yet been understood in terms of modern pharmacological concepts. The purpose of this study is to investigate the effects of corn silk ...

  18. Experimental investigation of pyrolysis process of corn straw

    OpenAIRE

    Lei Wang; Shengqiang Shen; Shuhua Yang; Xinguang Shi

    2010-01-01

    The present paper was performed to analyze the pyrolysis process of corn straw. Based on the thermogravimetric analysis, the component of pyrolysis gas of corn straw was tested using the gas chromatograph analyzer. Experimental results showed that, as the reaction temperature increases, the component of H 2 and CH 4 increases, whereas the component of CO and CO 2 decreases. Finally, the mechanism of pyrolysis process of corn straw was revealed from the point of view of the molecular structure...

  19. Handling Indian corn on the cob (for the alcohol industry)

    Energy Technology Data Exchange (ETDEWEB)

    Podurazhnyi, Y K

    1962-01-01

    The corn grains are mechanically prepared from the cob shortly before malting, the wort is boiled at 142 to 144/sup 0/, and is made up of corn 34, beets 40, and molasses 26%, providing an alcohol liquor which contains on the average 7.34% (individual values as high as 8.6) ethanol. This application of corn on the cob incurs (on the base of prices in the Soviet Union) a saving of about 20% in ethanol manufacture.

  20. Microscopic Analysis of Corn Fiber Using Corn Starch- and Cellulose-Specific Molecular Probes

    Energy Technology Data Exchange (ETDEWEB)

    Porter, S. E.; Donohoe, B. S.; Beery, K. E.; Xu, Q.; Ding, S.-Y.; Vinzant, T. B.; Abbas, C. A.; Himmel, M. E.

    2007-09-01

    Ethanol is the primary liquid transportation fuel produced from renewable feedstocks in the United States today. The majority of corn grain, the primary feedstock for ethanol production, has been historically processed in wet mills yielding products such as gluten feed, gluten meal, starch, and germ. Starch extracted from the grain is used to produce ethanol in saccharification and fermentation steps; however the extraction of starch is not 100% efficient. To better understand starch extraction during the wet milling process, we have developed fluorescent probes that can be used to visually localize starch and cellulose in samples using confocal microscopy. These probes are based on the binding specificities of two types of carbohydrate binding modules (CBMs), which are small substrate-specific protein domains derived from carbohydrate degrading enzymes. CBMs were fused, using molecular cloning techniques, to a green fluorescent protein (GFP) or to the red fluorescent protein DsRed (RFP). Using these engineered probes, we found that the binding of the starch-specific probe correlates with starch content in corn fiber samples. We also demonstrate that there is starch internally localized in the endosperm that may contribute to the high starch content in corn fiber. We also surprisingly found that the cellulose-specific probe did not bind to most corn fiber samples, but only to corn fiber that had been hydrolyzed using a thermochemical process that removes the residual starch and much of the hemicellulose. Our findings should be of interest to those working to increase the efficiency of the corn grain to ethanol process.

  1. 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

  2. Kernel compositions of glyphosate-tolerant and corn rootworm-protected MON 88017 sweet corn and insect-protected MON 89034 sweet corn are equivalent to that of conventional sweet corn (Zea mays).

    Science.gov (United States)

    Curran, Kassie L; Festa, Adam R; Goddard, Scott D; Harrigan, George G; Taylor, Mary L

    2015-03-25

    Monsanto Co. has developed two sweet corn hybrids, MON 88017 and MON 89034, that contain biotechnology-derived (biotech) traits designed to enhance sustainability and improve agronomic practices. MON 88017 confers benefits of glyphosate tolerance and protection against corn rootworm. MON 89034 provides protection against European corn borer and other lepidopteran insect pests. The purpose of this assessment was to compare the kernel compositions of MON 88017 and MON 89034 sweet corn with that of a conventional control that has a genetic background similar to the biotech sweet corn but does not express the biotechnology-derived traits. The sweet corn samples were grown at five replicated sites in the United States during the 2010 growing season and the conventional hybrid and 17 reference hybrids were grown concurrently to provide an estimate of natural variability for all assessed components. The compositional analysis included proximates, fibers, amino acids, sugars, vitamins, minerals, and selected metabolites. Results highlighted that MON 88017 and MON 89034 sweet corns were compositionally equivalent to the conventional control and that levels of the components essential to the desired properties of sweet corn, such as sugars and vitamins, were more affected by growing environment than the biotech traits. In summary, the benefits of biotech traits can be incorporated into sweet corn with no adverse effects on nutritional quality.

  3. Corn fiber hulls as a food additive or animal feed

    Science.gov (United States)

    Abbas, Charles; Beery, Kyle E.; Cecava, Michael J.; Doane, Perry H.

    2010-12-21

    The present invention provides a novel animal feed or food additive that may be made from thermochemically hydrolyzed, solvent-extracted corn fiber hulls. The animal feed or food additive may be made, for instance, by thermochemically treating corn fiber hulls to hydrolyze and solubilize the hemicellulose and starch present in the corn fiber hulls to oligosaccharides. The residue may be extracted with a solvent to separate the oil from the corn fiber, leaving a solid residue that may be prepared, for instance by aggolmerating, and sold as a food additive or an animal feed.

  4. 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

  5. Effect of length of interval between cereal rye cover crop termination and corn planting on seedling root disease and corn growth

    Science.gov (United States)

    Cereal rye cover crops terminated immediately before corn planting can sometimes reduce corn population, early growth, and yield. We hypothesized that cereal rye may act as a green bridge for corn pathogens and may increase corn seedling root disease. A field experiment was conducted over two years ...

  6. Effect of hydrothermal treated corn flour addition on the quality of corn-field bean gluten-free pasta

    OpenAIRE

    Dib Ahlem; Wójtowicz Agnieszka; Benatallah Leila; Bouasla Abdallah; Zidoune Mohammed Nasreddine

    2018-01-01

    Corn semolina supplemented by field bean semolina in ratio of 2/1 (w/w) were used for obtaining protein and fiber enriched gluten-free pasta. The effect of hydrothermal treatment of corn flour on its applicability as gluten-free pasta improver was tested. A central composite design involving water hydration level and the amount of hydrothermal treated corn flour were used. Instrumental analyses of pasta (cooking loss, water absorption capacity, hydration and pasting properties, textural param...

  7. The effects of corn silk on glycaemic metabolism.

    Science.gov (United States)

    Guo, Jianyou; Liu, Tongjun; Han, Linna; Liu, Yongmei

    2009-11-23

    Corn silk contains proteins, vitamins, carbohydrates, Ca, K, Mg and Na salts, fixed and volatile oils, steroids such as sitosterol and stigmasterol, alkaloids, saponins, tannins, and flavonoids. Base on folk remedies, corn silk has been used as an oral antidiabetic agent in China for decades. However, the hypoglycemic activity of it has not yet been understood in terms of modern pharmacological concepts. The purpose of this study is to investigate the effects of corn silk on glycaemic metabolism. Alloxan and adrenalin induced hyperglycemic mice were used in the study. The effects of corn silk on blood glucose, glycohemoglobin (HbA1c), insulin secretion, damaged pancreatic beta-cells, hepatic glycogen and gluconeogenesis in hyperglycemic mice were studied respectively. After the mice were orally administered with corn silk extract, the blood glucose and the HbA1c were significantly decreased in alloxan-induced hyperglycemic mice (p corn silk extract 15 days later. Also, the body weight of the alloxan-induced hyperglycemic mice was increased gradually. However, ascension of blood glucose induced by adrenalin and gluconeogenesis induced by L-alanine were not inhibited by corn silk extract treatment (p > 0.05). Although corn silk extract increased the level of hepatic glycogen in the alloxan-induced hyperglycemic mice, there was no significant difference between them and that of the control group(p > 0.05). Corn silk extract markedly reduced hyperglycemia in alloxan-induced diabetic mice. The action of corn silk extract on glycaemic metabolism is not via increasing glycogen and inhibiting gluconeogenesis but through increasing insulin level as well as recovering the injured beta-cells. The results suggest that corn silk extract may be used as a hypoglycemic food or medicine for hyperglycemic people in terms of this modern pharmacological study.

  8. Rapid corn and soybean mapping in US Corn Belt and neighboring areas

    Science.gov (United States)

    Zhong, Liheng; Yu, Le; Li, Xuecao; Hu, Lina; Gong, Peng

    2016-11-01

    The goal of this study was to promptly map the extent of corn and soybeans early in the growing season. A classification experiment was conducted for the US Corn Belt and neighboring states, which is the most important production area of corn and soybeans in the world. To improve the timeliness of the classification algorithm, training was completely based on reference data and images from other years, circumventing the need to finish reference data collection in the current season. To account for interannual variability in crop development in the cross-year classification scenario, several innovative strategies were used. A random forest classifier was used in all tests, and MODIS surface reflectance products from the years 2008-2014 were used for training and cross-year validation. It is concluded that the fuzzy classification approach is necessary to achieve satisfactory results with R-squared ~0.9 (compared with the USDA Cropland Data Layer). The year of training data is an important factor, and it is recommended to select a year with similar crop phenology as the mapping year. With this phenology-based and cross-year-training method, in 2015 we mapped the cropping proportion of corn and soybeans around mid-August, when the two crops just reached peak growth.

  9. Corn Storage Protein - A Molecular Genetic Model

    Energy Technology Data Exchange (ETDEWEB)

    Messing, Joachim [Rutgers Univ., Piscataway, NJ (United States)

    2013-05-31

    Corn is the highest yielding crop on earth and probably the most valuable agricultural product of the United States. Because it converts sun energy through photosynthesis into starch and proteins, we addressed energy savings by focusing on protein quality. People and animals require essential amino acids derived from the digestion of proteins. If proteins are relatively low in certain essential amino acids, the crop becomes nutritionally defective and has to be supplemented. Such deficiency affects meat and fish production and countries where corn is a staple. Because corn seed proteins have relatively low levels of lysine and methionine, a diet has to be supplemented with soybeans for the missing lysine and with chemically synthesized methionine. We therefore have studied genes expressed during maize seed development and their chromosomal organization. A critical technical requirement for the understanding of the molecular structure of genes and their positional information was DNA sequencing. Because of the length of sequences, DNA sequencing methods themselves were insufficient for this type of analysis. We therefore developed the so-called “DNA shotgun sequencing” strategy, where overlapping DNA fragments were sequenced in parallel and used to reconstruct large DNA molecules via overlaps. Our publications became the most frequently cited ones during the decade of 1981-1990 and former Associate Director of Science for the Office of Basic Energy Sciences Patricia M. Dehmer presented our work as one of the great successes of this program. A major component of the sequencing strategy was the development of bacterial strains and vectors, which were also used to develop the first biotechnology crops. These crops possessed new traits thanks to the expression of foreign genes in plants. To enable such expression, chimeric genes had to be constructed using our materials and methods by the industry. Because we made our materials and methods freely available to

  10. Analyzing the impacts of three types of biochar on soil carbon fractions and physiochemical properties in a corn-soybean rotation.

    Science.gov (United States)

    Sandhu, Saroop S; Ussiri, David A N; Kumar, Sandeep; Chintala, Rajesh; Papiernik, Sharon K; Malo, Douglas D; Schumacher, Thomas E

    2017-10-01

    Biochar is a solid material obtained when biomass is thermochemically converted in an oxygen-limited environment. In most previous studies, the impacts of biochar on soil properties and organic carbon (C) were investigated under controlled conditions, mainly laboratory incubation or greenhouse studies. This 2-year field study was conducted to evaluate the influence of biochar on selected soil physical and chemical properties and carbon and nitrogen fractions for two selected soil types (clay loam and a sandy loam soil) under a corn (Zea mays L.)-soybean (Glycine max L.) rotation. The three plant based biochar materials used for this study were corn stover (CS), ponderosa pine (Pinus ponderosa Lawson and C. Lawson) wood residue (PW), and switchgrass (Panicum virgatum L.) (SG). Data showed that CS and SG significantly increased the pH of acidic soil at the eroded landscape position but produced no significant change in soil pH at the depositional landscape position. The effects of biochar treatments on cold water extractable C (WSC) and nitrogen (WSN) fractions for the 0-7.5 cm depth were depended on biochar and soil type. Results suggested that alkaline biochars applied at 10 Mg ha -1 can increase the pH and WSC fraction of acidic sandy loam soil, but the 10 Mg ha -1 rate might be low to substantially improve physical properties and hot water extractable C and N fractions of soil. Application of higher rates of biochar and long-term monitoring is needed to quantify the benefits of biochar under field conditions on soils in different environmental conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Carbofuran affects wildlife on Virginia corn fields

    Science.gov (United States)

    Stinson, E.R.; Hayes, L.E.; Bush, P.B.; White, D.H.

    1994-01-01

    Forty-four Virginia corn fields on 11 farms were searched for evidence of dead or debilitated wildlife following in-furrow application of granular carbofuran (Furadan 15G) during April and May 1991. Evidence of pesticide poisoned wildlife, including dead animals, debilitated animals, feather spots, and fur spots was found on 33 fields on 10 farms. Carcasses of 61 birds, 4 mammals, and 1 reptile were recovered. Anticholinesterase poisoning was confirmed or suspected as the cause of most wildlife deaths based on the circumstances surrounding kills, necropsies of Carcasses, residue analyses, and brain ChE assays.

  12. Impact of transgenic sweet corn silks to two noctuid pests

    Science.gov (United States)

    Eight Bacillus thuringiensis (Bt) transgenic sweet corn hybrids were evaluated (with two controls) for their efficacy against two ear-feeding insects; the corn earworm [Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae)], and the fall armyworm (Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuid...

  13. Acute and Subacute Toxicity Evaluation of Corn Silk Extract.

    Science.gov (United States)

    Ha, Ae Wha; Kang, Hyeon Jung; Kim, Sun Lim; Kim, Myung Hwan; Kim, Woo Kyoung

    2018-03-01

    Many studies have reported therapeutic efficacy of corn silk extract. However, research on its toxicity and safe dose range is limited. Thus, the objective of this study was to determine the acute and subacute toxicity of corn silk extract in ICR mice. To determine acute toxicity, corn silk extract containing high levels of maysin was orally administered to mice at a dose of 0 or 2,000 mg/kg. Clinical symptoms, mortality, and body weight changes were recorded for 14 days. To determine subacute toxicity, corn silk extract was orally administered to mice over a 4-week period, and then body weight, water and food consumption, and organ weight were determined. In addition, urine and serum analyses were performed. In the acute toxicity study, no death or abnormal symptoms was observed in all treatment groups during the study period. Body weights did not show any significant change compared to those of the control group. Lethal dose of corn silk extract was estimated to be more than 2,000 mg/kg. In the 4-week subacute toxicity study, there was no corn silk extract related toxic effect on body weight, water intake, food consumption, urine parameters, clinical chemistry, or organ weight. Histopathological examination showed no abnormality related to the administration of corn silk extract at 500 mg/kg. The maximum non-toxic dose of corn silk extract containing high levels of maysin was found to be more than 500 mg/kg.

  14. Preparation and In vitro Digestibility of Corn Starch Phosphodiester ...

    African Journals Online (AJOL)

    Purpose: To optimize the process conditions and analyze in vitro digestibility of corn starch phosphodiester prepared by sodium trimetaphosphate (STMP). Methods: By using response surface method, the effects of STMP concentration, pH, esterification temperature, and urea addition on digestion resistance of corn starch ...

  15. Accounting for alfalfa N credits increases returns to corn production

    Science.gov (United States)

    Guidelines are relatively consistent across the Upper Midwest regarding the N benefit of alfalfa to the following grain crops. With higher corn yields and prices, however, some growers have questioned these guidelines and whether more N fertilizer is needed for first-year corn following a good stand...

  16. Treatment of some Textile Industrial Effluents using Dry Corn Stalk ...

    African Journals Online (AJOL)

    Corn stalk ground to various mesh sizes was used to treat textile effluents obtained from three different industries. These effluents were first pretreated with alum and then charcoal; passing the water through a column, (20cm long and 5cm diameter) containing the ground corn stalk of size diameters of 300mm, 355mm ...

  17. Complementation of sweet corn mutants: a method for grouping ...

    Indian Academy of Sciences (India)

    for sweet corn are now expanding and the demands are increasing due to ... tropical/tropical regions of India is amongst one of the factors ... Maize endosperm mutant genes that affect quality of sweet corn can ... Thus, the concept of comple-.

  18. Climate change impacts on corn phenology and productivity

    Science.gov (United States)

    Climate is changing around the world and will impact future production of all food and feed crops. Corn is no exception to these impacts and to ensure a future supply of this vital crop we must begin to understand how climate impacts both the phenological development of corn and the productivity. Te...

  19. Fungal protein from corn waste effluents : a model study

    NARCIS (Netherlands)

    Schellart, J.A.

    1975-01-01

    The purpose of this investigation was to study the microbiological aspects of the production of microbial protein ('single cell protein'; SCP) from corn waste effluents with simultaneous reduction of the COD of these effluents.

    For practical reasons the corn waste water itself was

  20. Nonrenewable energy cost of corn-ethanol in China

    International Nuclear Information System (INIS)

    Yang, Q.; Chen, G.Q.

    2012-01-01

    Nonrenewable energy cost is accounted for the believed renewable biofuel of corn-ethanol in China. By a process-based energy analysis, nonrenewable energy cost in the corn-ethanol production process incorporating agricultural crop production, industrial conversion and wastewater treatment is conservatively estimated as 1.70 times that of the ethanol energy produced, corresponding to a negative energy return in contrast to the positive ones previously reported. Nonrenewable energy cost associated with wastewater treatment usually ignored in previous researches is shown important in the energy balance. Denoting the heavy nonrenewability of the produced corn-ethanol, the calculated nonrenewable energy cost would rise to 3.64 folds when part of the nonrenewable energy cost associated with water consumption, transportation and environmental remediation is included. Due to the coal dominated nonrenewable energy structure in China, corn-ethanol processes in China are mostly a conversion of coal to ethanol. Validations and discussions are also presented to reveal policy implications against corn based ethanol as an alternative energy in long term energy security planning. - Highlights: ► Nonrenewable energy (NE) cost is conservatively accounted for corn-ethanol in China. ► Corn cultivation, ethanol conversion and wastewater treatment are included. ► NE cost is estimated as 1.70 times that of the ethanol energy produced. ► Corn-ethanol processes in China are mostly a conversion of coal to ethanol.

  1. 21 CFR 184.1866 - High fructose corn syrup.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true High fructose corn syrup. 184.1866 Section 184.1866... Listing of Specific Substances Affirmed as GRAS § 184.1866 High fructose corn syrup. (a) High fructose... partial enzymatic conversion of glucose (dextrose) to fructose using an insoluble glucose isomerase enzyme...

  2. Winter cover crop effect on corn seedling pathogens

    Science.gov (United States)

    Cover crops are an excellent management tool to improve the sustainability of agriculture. Winter rye cover crops have been used successfully in Iowa corn-soybean rotations. Unfortunately, winter rye cover crops occasionally reduce yields of the following corn crop. We hypothesize that one potential...

  3. The perception of corn farmers about biological control of Caradrina ...

    African Journals Online (AJOL)

    The purpose of this study was to analyze the perception of corn farmers about biological control of Caradrina by Braconid in Dezful Township, Khouzestan Province, Iran. The method used in this study was correlative descriptive and causal relation. A random sample of Dezful township corn farmers of Khouzestan Province, ...

  4. Effect of corn cobs concentration on xylanase biosynthesis by ...

    African Journals Online (AJOL)

    Corn cobs, an indigenous carbon source, were tested as substrate by Aspergillus niger for optimum synthesis of xylanase using the submerged fermentation technique. The trials for xylanase production were conducted at three concentration levels (2.5, 3.0 and 3.5%) of corn cobs, four different fermentation temperatures ...

  5. Cultivation of mushroom ( Pleurotus ostreatus ) using corn cobs and ...

    African Journals Online (AJOL)

    An investigation was carried out on the cultivation of mushroom (Pleurotus ostreatus) using corn cobs and saw dust as the main substrates. Lignocellulosic wastes such as corn cobs and saw dust were packaged inside heat – resistant polythene bags and pasteurized before being seeded with 7.5% w/w millet spawn of ...

  6. SILAGE QUALITY OF CORN AND SORGHUM ADDED WITH FORAGE PEANUTS

    Directory of Open Access Journals (Sweden)

    WALKÍRIA GUIMARÃES CARVALHO

    2016-01-01

    Full Text Available Corn and sorghum are standard silage crops because of their fermentative characteristics. While corn and sorghum silages have lower crude protein (CP contents than other crops, intercropping with legumes can increase CP content. Furthermore, one way to increase CP content is the addition of legumes to silage. Consequently, the research objective was to evaluate the fermentative and bromatological characteristics of corn (Zea mays and sorghum (Sorghum bicolor silages added with forage peanuts (Arachis pintoi. The experimental design was completely randomized with four replicates. The treatments consisted of corn silage, sorghum silage, forage peanut silage, corn silage with 30% forage peanut, and sorghum silage with 30% forage peanut. The results showed that the corn and sorghum added with peanut helped to improve the silage fermentative and bromatological characteristics, proving to be an efficient technique for silage quality. The forage peanut silage had lower fermentative characteristics than the corn and sorghum silages. However, the forage peanut silage had a greater CP content, which increased the protein contents of the corn and sorghum silages when intercropped with forage peanuts.

  7. Corn silk induces nitric oxide synthase in murine macrophages.

    Science.gov (United States)

    Kim, Kyung A; Choi, Sang Kyu; Choi, Hye Seon

    2004-12-31

    Corn silk has been purified as an anticoagulant previously and the active component is a polysaccharide with a molecular mass of 135 kDa. It activates murine macrophages to induce nitric oxide synthase (NOS) and generate substantial amounts of NO in time and dose-dependent manners. It was detectable first at 15 h after stimulation by corn silk, peaked at 24 h, and undetectable by 48 h. Induction of NOS is inhibited by pyrolidine dithiocarbamate (PDTC) and genistein, an inhibitor of nuclear factor kappa B (NF-kappaB) and tyrosine kinase, respectively, indicating that iNOS stimulated by corn silk is associated with tyrosine kinase and NF-kappaB signaling pathways. IkappaB-alpha degradation was detectible at 10 min, and the level was restored at 120 min after treatment of corn silk. Corn silk induced nuclear translocation of NF-kappaB by phosphorylation and degradation of IkappaB-alpha.

  8. Lead and copper immobilization in a shooting range soil using soybean stover- and pine needle-derived biochars: Chemical, microbial and spectroscopic assessments

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Mahtab [Korea Biochar Research Center & Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Soil Sciences Department, College of Food and Agricultural Sciences, King Saud University, PO Box 2460, Riyadh 11451 (Saudi Arabia); Ok, Yong Sik; Rajapaksha, Anushka Upamali; Lim, Jung Eun [Korea Biochar Research Center & Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Kim, Byung-Yong; Ahn, Jae-Hyung [Agricultural Microbiology Division, National Academy of Agricultural Science, Rural Development Administration, Wanju 565-851 (Korea, Republic of); Lee, Young Han [Division of Plant Environment Research, Gyeongsangnam-do Agricultural Research and Extension Service, Jinju 660-360 (Korea, Republic of); Al-Wabel, Mohammad I [Soil Sciences Department, College of Food and Agricultural Sciences, King Saud University, PO Box 2460, Riyadh 11451 (Saudi Arabia); Lee, Sung-Eun, E-mail: selpest@knu.ac.kr [School of Applied Biosciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Lee, Sang Soo, E-mail: sslee97@kangwon.ac.kr [Korea Biochar Research Center & Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of)

    2016-01-15

    Highlights: • Biochar immobilizes Pb and Cu in a contaminated shooting range soil. • Soybean stover-biochar is an efficient metal immobilizer than pine needle-biochar. • Biochar produced at 700 °C showed significant potential of sequestering C in soil. • Biochar showed less impact on the bacterial community than feedstock biomass. - Abstract: Biochar (BC) could be a potential candidate for the remediation of metal contaminated soil. Mechanistic understandings are needed for the appropriate selection of BC and investigating molecular microbial ecological interactions. The soybean stover-derived BCs were more effective in immobilizing Pb (88%) and Cu (87%) than the pine needle-derived BCs in a contaminated shooting range soil. The sequential chemical extractions indicated that BCs stimulated the geochemical transformation of metal species. Spectroscopic investigations using scanning electron microscopic elemental dot mapping and extended X-ray absorption fine structure spectroscopic measurements showed that Pb in the BCs amended soils was immobilized by the formation of stable chloropyromorphite. Soil organic C and microbial activity were also enhanced by BC. The non-labile C fraction in the soil amended with BCs produced at 700 °C was increased. Biochars showed less impact on the bacterial community than feedstock biomass as promulgated by the pyrosequencing of 16S rRNA gene. The feedstock type (namely soybean stover and pine needles) was the main factor influencing the BCs efficacy on metals’ (im) mobilization and bacterial health in soils.

  9. Lead and copper immobilization in a shooting range soil using soybean stover- and pine needle-derived biochars: Chemical, microbial and spectroscopic assessments

    International Nuclear Information System (INIS)

    Ahmad, Mahtab; Ok, Yong Sik; Rajapaksha, Anushka Upamali; Lim, Jung Eun; Kim, Byung-Yong; Ahn, Jae-Hyung; Lee, Young Han; Al-Wabel, Mohammad I; Lee, Sung-Eun; Lee, Sang Soo

    2016-01-01

    Highlights: • Biochar immobilizes Pb and Cu in a contaminated shooting range soil. • Soybean stover-biochar is an efficient metal immobilizer than pine needle-biochar. • Biochar produced at 700 °C showed significant potential of sequestering C in soil. • Biochar showed less impact on the bacterial community than feedstock biomass. - Abstract: Biochar (BC) could be a potential candidate for the remediation of metal contaminated soil. Mechanistic understandings are needed for the appropriate selection of BC and investigating molecular microbial ecological interactions. The soybean stover-derived BCs were more effective in immobilizing Pb (88%) and Cu (87%) than the pine needle-derived BCs in a contaminated shooting range soil. The sequential chemical extractions indicated that BCs stimulated the geochemical transformation of metal species. Spectroscopic investigations using scanning electron microscopic elemental dot mapping and extended X-ray absorption fine structure spectroscopic measurements showed that Pb in the BCs amended soils was immobilized by the formation of stable chloropyromorphite. Soil organic C and microbial activity were also enhanced by BC. The non-labile C fraction in the soil amended with BCs produced at 700 °C was increased. Biochars showed less impact on the bacterial community than feedstock biomass as promulgated by the pyrosequencing of 16S rRNA gene. The feedstock type (namely soybean stover and pine needles) was the main factor influencing the BCs efficacy on metals’ (im) mobilization and bacterial health in soils.

  10. Low-airflow drying of fungicide-treated shelled corn

    International Nuclear Information System (INIS)

    Peterson, W.H.; Benson, P.W.

    1993-02-01

    Approved fungicides inhibit mold growth in shelled corn and allow for longer, natural-air drying. The longer drying periods permit lower than-normal airflows and smaller power units, thus reducing electrical demands on utilities in corn-producing states. Researchers placed approximately 67 m 3 (1900 bu) of one variety of shelled corn at approximately 24% moisture in each of five equally sized storage bins. They partitioned each bin vertically and filled one half of each bin with fungicide-treated corn and one half with untreated corn. Each of four bins used a different airflow. A fifth bin used the lowest of the four airflows but was equipped to capture and use solar energy. All corn dried rapidly with resulting good quality. The percentage of damaged kernels was significantly higher for untreated than for treated corn. The energy required for the lowest airflow system was approximately one half of that required for the higher, more traditional airflows. Because of lower-than-normal airflows, the electrical demand on the utility is approximately one fourth as great as that imposed when the higher, more traditional natural-air systems are used. The 1991 corn growing and drying seasons were unusual in central Illinois, the site of the study. Both harvest and drying occurred several weeks ahead of schedule. Additional work is needed to verify that findings hold true during more-normal Midwest corn growing and drying seasons; the investigators predict that they will. It should be noted that the fungicide used in this study has not yet been approved for widespread use in drying corn

  11. Aflatoxin contamination in corn sold for wildlife feed in texas.

    Science.gov (United States)

    Dunham, Nicholas R; Peper, Steven T; Downing, Carson D; Kendall, Ronald J

    2017-05-01

    Supplemental feeding with corn to attract and manage deer is a common practice throughout Texas. Other species, including northern bobwhites (Colinus virginianus), are commonly seen feeding around supplemental deer feeders. In many cases, supplemental feeding continues year-round so feed supply stores always have supplemental corn in stock. Fluctuating weather and improper storage of corn can lead to and/or amplify aflatoxin contamination. Due to the recent decline of bobwhites throughout the Rolling Plains ecoregion of Texas, there has been interest in finding factors such as toxins that could be linked to their decline. In this study, we purchased and sampled supplemental corn from 19 locations throughout this ecoregion to determine if aflatoxin contamination was present in individual bags prior to being dispersed to wildlife. Of the 57 bags sampled, 33 bags (approximately 58%) contained aflatoxin with a bag range between 0.0-19.91 parts per billion (ppb). Additionally, three metal and three polypropylene supplemental feeders were each filled with 45.4 kg of triple cleaned corn and placed in an open field to study long-term aflatoxin buildup. Feeders were sampled every 3 months from November 2013-November 2014. Average concentration of aflatoxin over the year was 4.08 ± 2.53 ppb (±SE) in metal feeders, and 1.43 ± 0.89 ppb (±SE) in polypropylene feeders. The concentration of aflatoxins is not affected by the type of feeder (metal vs polypropylene), the season corn was sampled, and the location in the feeder (top, middle, bottom) where corn is sampled. It is unlikely that corn used in supplemental feeders is contributing to the bobwhite decline due to the low levels of aflatoxin found in purchased corn and long-term storage of corn used in supplemental feeders.

  12. [Anaerobic co-digestion of corn stalk and vermicompost].

    Science.gov (United States)

    Chen, Guang-yin; Zheng, Zheng; Zou, Xing-xing; Fang, Cai-xia; Luo, Yan

    2010-02-01

    The characteristics of corn stalk digested alone at different total solid (TS) loading rates and co-digestion of various proportions of corn stalk and vermicompost were investigated by batch model at 35 degrees C +/- 1 degrees C. The organic loading rates (OLRs) studied were in the range of 1.2%-6.0% TS and increasing proportions of vermicompost from 20% to 80% TS. A maximum methane yield of corn stalk digested alone was 217.60 mL/g obtained at the TS loading rate of 4.8%. However, when the TS loading rate was 6.0%, the anaerobic system was acidified and the lowest pH value was 5.10 obtained on day 4 and the biogas productivity decreased. Furthermore, co-digestion of vermicompost and corn stalk in varying proportions were investigated at constant of 6.0% TS. Co-digestion with vermicompost improved the biodegradability of corn stalk and the methane yield was improved by 4.42%-58.61%, and led to higher pH values, higher volatile fatty acids (VFAs) concentration and lower alkalinity content compared with corn stalk digested alone. The maximum biogas yield and methane yield of 410.30 mL/g and 259. 35 mL/g were obtained for 40% vermicompost and 60% corn stalk respectively. Compared with corn stalk digested alone, co-digested with vermicompost didn' t affect methane content and the fermentation type, but promoted the destruction of crystalline of cellulose and the highest destruction rate was 29.36% for 40% vermicompost and 60% corn stalk. Therefore, adding vermicompost was beneficial for the decomposition and increasing the biotransformation rate of corn stalk.

  13. Market-oriented ethanol and corn-trade policies can reduce climate-induced US corn price volatility

    International Nuclear Information System (INIS)

    Verma, Monika; Diffenbaugh, Noah; Hertel, Thomas

    2014-01-01

    Agriculture is closely affected by climate. Over the past decade, biofuels have emerged as another important factor shaping the agricultural sector. We ask whether the presence of the US ethanol sector can play a role in moderating increases in US corn price variability, projected to occur in response to near-term global warming. Our findings suggest that the answer to this question depends heavily on the underlying forces shaping the ethanol industry. If mandate-driven, there is little doubt that the presence of the corn-ethanol sector will exacerbate price volatility. However, if market-driven, then the emergence of the corn-ethanol sector can be a double-edged sword for corn price volatility, possibly cushioning the impact of increased climate driven supply volatility, but also inheriting volatility from the newly integrated energy markets via crude oil price fluctuations. We find that empirically the former effect dominates, reducing price volatility by 27%. In contrast, mandates on ethanol production increase future price volatility by 54% in under future climate after 2020. We also consider the potential for liberalized international corn trade to cushion corn price volatility in the US. Our results suggest that allowing corn to move freely internationally serves to reduce the impact of near-term climate change on US corn price volatility by 8%. (letter)

  14. Market-oriented ethanol and corn-trade policies can reduce climate-induced US corn price volatility

    Science.gov (United States)

    Verma, Monika; Hertel, Thomas; Diffenbaugh, Noah

    2014-05-01

    Agriculture is closely affected by climate. Over the past decade, biofuels have emerged as another important factor shaping the agricultural sector. We ask whether the presence of the US ethanol sector can play a role in moderating increases in US corn price variability, projected to occur in response to near-term global warming. Our findings suggest that the answer to this question depends heavily on the underlying forces shaping the ethanol industry. If mandate-driven, there is little doubt that the presence of the corn-ethanol sector will exacerbate price volatility. However, if market-driven, then the emergence of the corn-ethanol sector can be a double-edged sword for corn price volatility, possibly cushioning the impact of increased climate driven supply volatility, but also inheriting volatility from the newly integrated energy markets via crude oil price fluctuations. We find that empirically the former effect dominates, reducing price volatility by 27%. In contrast, mandates on ethanol production increase future price volatility by 54% in under future climate after 2020. We also consider the potential for liberalized international corn trade to cushion corn price volatility in the US. Our results suggest that allowing corn to move freely internationally serves to reduce the impact of near-term climate change on US corn price volatility by 8%.

  15. Field-Evolved Resistance in Corn Earworm to Cry Proteins Expressed by Transgenic Sweet Corn

    Science.gov (United States)

    Dively, Galen P.; Finkenbinder, Chad

    2016-01-01

    Background Transgenic corn engineered with genes expressing insecticidal toxins from the bacterium Bacillus thuringiensis (Berliner) (Bt) are now a major tool in insect pest management. With its widespread use, insect resistance is a major threat to the sustainability of the Bt transgenic technology. For all Bt corn expressing Cry toxins, the high dose requirement for resistance management is not achieved for corn earworm, Helicoverpa zea (Boddie), which is more tolerant to the Bt toxins. Methodology/Major Findings We present field monitoring data using Cry1Ab (1996–2016) and Cry1A.105+Cry2Ab2 (2010–2016) expressing sweet corn hybrids as in-field screens to measure changes in field efficacy and Cry toxin susceptibility to H. zea. Larvae successfully damaged an increasing proportion of ears, consumed more kernel area, and reached later developmental stages (4th - 6th instars) in both types of Bt hybrids (Cry1Ab—event Bt11, and Cry1A.105+Cry2Ab2—event MON89034) since their commercial introduction. Yearly patterns of H. zea population abundance were unrelated to reductions in control efficacy. There was no evidence of field efficacy or tissue toxicity differences among different Cry1Ab hybrids that could contribute to the decline in control efficacy. Supportive data from laboratory bioassays demonstrate significant differences in weight gain and fitness characteristics between the Maryland H. zea strain and a susceptible strain. In bioassays with Cry1Ab expressing green leaf tissue, Maryland H. zea strain gained more weight than the susceptible strain at all concentrations tested. Fitness of the Maryland H. zea strain was significantly lower than that of the susceptible strain as indicated by lower hatch rate, longer time to adult eclosion, lower pupal weight, and reduced survival to adulthood. Conclusions/Significance After ruling out possible contributing factors, the rapid change in field efficacy in recent years and decreased susceptibility of H. zea to Bt

  16. Evaluation of the quality of the college library websites in Iranian medical Universities based on the Stover model.

    Science.gov (United States)

    Nasajpour, Mohammad Reza; Ashrafi-Rizi, Hasan; Soleymani, Mohammad Reza; Shahrzadi, Leila; Hassanzadeh, Akbar

    2014-01-01

    Today, the websites of college and university libraries play an important role in providing the necessary services for clients. These websites not only allow the users to access different collections of library resources, but also provide them with the necessary guidance in order to use the information. The goal of this study is the quality evaluation of the college library websites in Iranian Medical Universities based on the Stover model. This study uses an analytical survey method and is an applied study. The data gathering tool is the standard checklist provided by Stover, which was modified by the researchers for this study. The statistical population is the college library websites of the Iranian Medical Universities (146 websites) and census method was used for investigation. The data gathering method was a direct access to each website and filling of the checklist was based on the researchers' observations. Descriptive and analytical statistics (Analysis of Variance (ANOVA)) were used for data analysis with the help of the SPSS software. The findings showed that in the dimension of the quality of contents, the highest average belonged to type one universities (46.2%) and the lowest average belonged to type three universities (24.8%). In the search and research capabilities, the highest average belonged to type one universities (48.2%) and the lowest average belonged to type three universities. In the dimension of facilities provided for the users, type one universities again had the highest average (37.2%), while type three universities had the lowest average (15%). In general the library websites of type one universities had the highest quality (44.2%), while type three universities had the lowest quality (21.1%). Also the library websites of the College of Rehabilitation and the College of Paramedics, of the Shiraz University of Medical Science, had the highest quality scores. The results showed that there was a meaningful difference between the quality

  17. 7 CFR 319.24a - Administrative instructions relating to entry of corn into Guam.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Administrative instructions relating to entry of corn...) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE FOREIGN QUARANTINE NOTICES Corn Diseases Quarantine § 319.24a Administrative instructions relating to entry of corn into Guam. Corn may be...

  18. 7 CFR 319.24-4 - Notice of arrival of corn by permittee.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Notice of arrival of corn by permittee. 319.24-4... HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE FOREIGN QUARANTINE NOTICES Corn Diseases Regulations Governing Entry of Indian Corn Or Maize § 319.24-4 Notice of arrival of corn by permittee. Immediately upon...

  19. 19 CFR 10.57 - Certified seed potatoes, and seed corn or maize.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Certified seed potatoes, and seed corn or maize... Provisions Potatoes, Corn, Or Maize § 10.57 Certified seed potatoes, and seed corn or maize. Claim for classification as seed potatoes under subheading 0701.10.00, as seed corn (maize) under subheading 1005.10...

  20. 75 FR 56911 - Request for Public Comment on the United States Standards for Corn

    Science.gov (United States)

    2010-09-17

    ... Public Comment on the United States Standards for Corn AGENCY: Grain Inspection, Packers and Stockyards... Standards and grading procedures for corn under the United States Grain Standards Act (USGSA). Since the standards were last revised, the use of corn for ethanol and the number of different varieties of corn has...

  1. Aerial spray deposition on corn silks applied at high and low spray rates

    Science.gov (United States)

    Corn earworm is a major pest of sweet corn, especially when grown organically. Aerial application of insecticides is important for both conventionally- and organically-grown sweet corn production as sweet corn is frequently irrigated to assure return on investment given the high production costs. ...

  2. 7 CFR 457.129 - Fresh market sweet corn crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Fresh market sweet corn crop insurance provisions. 457... sweet corn crop insurance provisions. The fresh market sweet corn crop insurance provisions for the 2008... Reinsured Policies Fresh Market Sweet Corn Crop Provisions 1. Definitions Allowable cost.—The dollar amount...

  3. Effect of eastern gamagrass on fall armyworm and corn earworm development

    Science.gov (United States)

    The fall armyworm, Spodoptera frugiperda (J.E. Smith) and the corn earworm, Helicoverpa zea (Boddie) are two important corn pests in the southern U.S. states. Effect of the leaves from the corn relative, the Eastern gamagrass (Tripsacum dactyloides L.) on fall armyworm and corn earworm development ...

  4. The induction of proteinases in corn and soybean by anoxia

    International Nuclear Information System (INIS)

    VanToai, T.; Hwang, Shihying

    1989-01-01

    This study characterized the anaerobic changes in proteinase activities in corn and soybean roots and to investigate the possibility that these changes might contribute to the differential anaerobiosis tolerance of the two species. After 24 h of anoxia, crude protein extracts from H60 corn and Keller soybean root tips (10cm) were assayed for proteinase activities at pH range from 4.5 to 9.5. Turnover of aberrant proteins was studied in seedlings labelled with 3 H-leucine for 12 h under: (a) puromycin (0.64 mM) in air, (b) ethanol (1%) in air, (c) nitrogen and (d) air. After the treatment, the labelled proteins remaining in roots were determined every 2 h for 6 h. In both corn and soybean, activities of alkali proteinases increased, and activities of acid proteinases declined under anoxia. Neutral proteinases increase in anoxic corn roots, but decline in anoxic soybean roots. The protein turnover rate in corn treated with puromycin, ethanol and nitrogen was much higher than in control roots. The protein turnover rate in soybean roots treated with puromycin, ethanol was similar to the rate of the control. The results indicated that: (a) anoxic corn can degrade aberrant proteins, but anoxic soybean cannot, (b) the degradation of aberrant proteins in anoxic corn is accomplished by neutral proteinases, and (c) the accumulation of aberrant proteins in soybean might contribute to the susceptibility of this species to anoxia

  5. Inhibitory effect of corn silk on skin pigmentation.

    Science.gov (United States)

    Choi, Sang Yoon; Lee, Yeonmi; Kim, Sung Soo; Ju, Hyun Min; Baek, Ji Hwoon; Park, Chul-Soo; Lee, Dong-Hyuk

    2014-03-03

    In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin production inhibitory effect at the same concentration. The corn silk extract did not suppress tyrosinase activity but greatly reduced the expression of tyrosinase in Melan-A cells. In addition, corn silk extract was applied to the human face with hyperpigmentation, and skin color was measured to examine the degree of skin pigment reduction. The application of corn silk extract on faces with hyperpigmentation significantly reduced skin pigmentation without abnormal reactions. Based on the results above, corn silk has good prospects for use as a material for suppressing skin pigmentation.

  6. Inhibitory Effect of Corn Silk on Skin Pigmentation

    Directory of Open Access Journals (Sweden)

    Sang Yoon Choi

    2014-03-01

    Full Text Available In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin production inhibitory effect at the same concentration. The corn silk extract did not suppress tyrosinase activity but greatly reduced the expression of tyrosinase in Melan-A cells. In addition, corn silk extract was applied to the human face with hyperpigmentation, and skin color was measured to examine the degree of skin pigment reduction. The application of corn silk extract on faces with hyperpigmentation significantly reduced skin pigmentation without abnormal reactions. Based on the results above, corn silk has good prospects for use as a material for suppressing skin pigmentation.

  7. Sustainable Dry Land Management Model on Corn Agribusiness System

    Directory of Open Access Journals (Sweden)

    Yulia Pujiharti

    2008-01-01

    Full Text Available The study aimed at building model of dry land management. Dynamic System Analysis was used to build model and Powersim 2.51 version for simulating. The parameter used in model were fertilizer (urea, SP-36, ACL, productivity (corn, cassava, mungbean, soil nutrient (N, P, K, crop nutrient requirements (corn, cassava, mungbean, mucuna, price (corn, cassava, mungbeans corn flour, feed, urea, SP-36, KCl, food security credit, area planted of (maize, cassava, mungbean, area harvested of (maize, cassava, mungbean, (corn, cassava, mungbean production, wages and farmer income. Sustainable indicator for ecology aspect was soil fertility level, economic aspects were productivity and farmer income, and social aspects were job possibility and traditions. The simulation result indicated that sustainable dry land management can improve soil fertility and increase farmer revenue, became sustainable farming system and farmer society. On the other hand, conventional dry land management decreased soil fertility and yield, caused farmer earnings to decrease and a farm activity could not be continued. Fertilizer distribution did not fulfill farmer requirement, which caused fertilizer scarcity. Food security credit increased fertilizer application. Corn was processed to corn flour or feed to give value added.

  8. The effects of corn silk on glycaemic metabolism

    Directory of Open Access Journals (Sweden)

    Han Linna

    2009-11-01

    Full Text Available Abstract Background Corn silk contains proteins, vitamins, carbohydrates, Ca, K, Mg and Na salts, fixed and volatile oils, steroids such as sitosterol and stigmasterol, alkaloids, saponins, tannins, and flavonoids. Base on folk remedies, corn silk has been used as an oral antidiabetic agent in China for decades. However, the hypoglycemic activity of it has not yet been understood in terms of modern pharmacological concepts. The purpose of this study is to investigate the effects of corn silk on glycaemic metabolism. Methods Alloxan and adrenalin induced hyperglycemic mice were used in the study. The effects of corn silk on blood glucose, glycohemoglobin (HbA1c, insulin secretion, damaged pancreatic β-cells, hepatic glycogen and gluconeogenesis in hyperglycemic mice were studied respectively. Results After the mice were orally administered with corn silk extract, the blood glucose and the HbA1c were significantly decreased in alloxan-induced hyperglycemic mice (p 0.05. Although corn silk extract increased the level of hepatic glycogen in the alloxan-induced hyperglycemic mice, there was no significant difference between them and that of the control group(p > 0.05. Conclusion Corn silk extract markedly reduced hyperglycemia in alloxan-induced diabetic mice. The action of corn silk extract on glycaemic metabolism is not via increasing glycogen and inhibiting gluconeogenesis but through increasing insulin level as well as recovering the injured β-cells. The results suggest that corn silk extract may be used as a hypoglycemic food or medicine for hyperglycemic people in terms of this modern pharmacological study.

  9. Aracnidae diversity in soil cultivated with corn (Zea mays

    Directory of Open Access Journals (Sweden)

    Lígia Vanessa da Silva

    2014-09-01

    Full Text Available Studies carried out on the diversity and abundance of spiders may provide a rich information base on the degree of integrity of agricultural systems where they are found. In transgenic corn, Bacillus thuringiensis proteins are expressed in great amounts in plant tissues and may affect arthropod communities. Thus, the main goal of this work was to identify the spider diversity associated to transgenic and conventional corn hybrids. Pitfall collections were performed in conventional and transgenic corn plots during the 2010/2011 crop season, at the experimental field of the Agronomy Course of the University of Cruz Alta, RS. A total of 559 spiders were collected, from which 263 were adults and 296 young individuals. In the transgenic corn 266 spiders were collected and in the conventional one 293. Eleven families were determined and the adult individuals grouped in 27 morphospecies. Families with the largest number of representatives were Linyphiidae (29.70%, Theridiidae (5.72% and Lycosidae (5.01%. The most abundant morphospecies were Lyniphiidae sp. with 77 individuals, Erigone sp. with 40 individuals, Lynyphiidae sp. with 33 individuals, Theridiidae sp. with 21 individuals, Lycosa erythrognatha with 14 individuals and Lycosidae sp. with 13 individuals. The Shannon Diversity Index was higher for transgenic corn (H” =1.01 in February and smaller (H’=0.54 in the December collection in the conventional corn, and the Margaleff Richness Index showed higher diversity in December and February for the conventional corn (M=18.3, and smaller diversity for the transgenic corn in November (M=11.3. Families were classified in five guilds; two weavers: Irregular web builders and sheet web builders, and three hunter guilds: Night soil runners, ambush spiders and aerial night runners. The relative proportion of the spiders morphospecies found in this research, as well as the guilds, suggest that this group may not have been affected by the genetically

  10. Assessing corn water stress using spectral reflectance

    Science.gov (United States)

    Mefford, Brenna S.

    Multiple remote sensing techniques have been developed to identify crop water stress, but some methods may be difficult for farmers to apply. Unlike most techniques, shortwave vegetation indices can be calculated using satellite, aerial, or ground imagery from the green (525-600 nm), red (625-700 nm), and near infrared (750-900 nm) spectral bands. If vegetation indices can be used to monitor crop water stress, growers could use this information as a quick low-cost guideline for irrigation management, thus helping save water by preventing over irrigating. This study occurred in the 2013 growing season near Greeley, CO, where pressurized drip irrigation was used to irrigate twelve corn ( Zea mays L.) treatments of varying water deficit. Multispectral data was collected and four different vegetation indices were evaluated: Normalized Difference Vegetation Index (NDVI), Optimized Soil-Adjusted Vegetation Index (OSAVI), Green Normalized Difference Vegetation Index (GNDVI), and the Wide Dynamic Range Vegetation Index (WDRVI). The four vegetation indices were compared to corn water stress as indicated by the stress coefficient (Ks) and water deficit in the root zone, calculated by using a water balance that monitors crop evapotranspiration (ET), irrigation events, precipitation events, and deep percolation. ET for the water balance was calculated using two different methods for comparison purposes: (1) calculation of the stress coefficient (Ks) using FAO-56 standard procedures; (2) use of canopy temperature ratio (Tc ratio) of a stressed crop to a non-stressed crop to calculate Ks. It was found that obtaining Ks from Tc ratio is a viable option, and requires less data to obtain than Ks from FAO-56. In order to compare the indices to Ks, vegetation ratios were developed in the process of normalization. Vegetation ratios are defined as the non-stressed vegetation index divided by the stressed vegetation index. Results showed that vegetation ratios were sensitive to water

  11. Radioimmunoassay of deoxynivalenol in wheat and corn

    International Nuclear Information System (INIS)

    Xu, Y.C.; Zhang, G.S.; Chu, F.S.

    1986-01-01

    With the availability of antibody against deoxynivalenol triacetate (DON-triacetate), a radioimmunoassay (RIA) for DON in wheat was developed. DON is extracted from the sample with acetonitrile-water defatted with hexane, and then reacted with acetic anhydride to form DON-triacetate. The reaction mixture is loaded onto a C-18 cartridge to remove excess reagents and impurities. Acetylated DON is eluted from the cartridge with 50% methanol in water, and then analyzed by radioimmunoassay utilizing antiserum against DON-triacetate and tritiated DON-triacetate. Overall recovery for DON added to wheat between 50 and 5000 ppb was 86% with a standard deviation of 7% and coefficient of variation of 8%. The limit of detection for DON was about 20 ppb. Analysis of 12 naturally contaminated wheat, corn, and mixed feed samples for DON revealed that RIA results agreed well with thin layer chromatographic analyses performed by other laboratories

  12. Hydrocolloid occlusion for the treatment of neurovascular corns

    DEFF Research Database (Denmark)

    Petersen, Lars Jelstrup; Beck, Jan Walther; Reumert, L N

    1991-01-01

    The goal of this study was to determine the effect of hydrocolloid occlusion on neurovascular corns. The design was an observer-blinded, randomized, controlled study. Thirty consecutive patients participated in the trial. The patients received curettage alone or curettage with hydrocolloid...... occlusion. Six treatments were given over 12 weeks. A follow-up examination was performed 3 months after termination of the trial. Outcome measures were the size of the corns, a discomfort score, and an overall judgment of the trial. The results demonstrated no benefit of occlusion for symptoms or signs...... of neurovascular corns. The patients treated with occlusion were, however, generally more satisfied than the conventional group....

  13. Identification of corn fields using multidate radar data

    International Nuclear Information System (INIS)

    Shanmugan, K.S.; Ulaby, F.T.; Narayanan, V.; Dobson, C.

    1983-01-01

    Airborne C- and L-band radar data acquired over a test site in western Kansas were analyzed to determine corn-field identification accuracies obtainable using single-channel, multichannel, and multidate radar data. An automated pattern-recognition procedure was used to classify 144 fields into three categories: corn, pasture land, and bare soil (including wheat stubble and fallow). Corn fields were identified with accuracies ranging from 85% for single channel, single-date data to 100% for single-channel, multidate data. The effects of radar parameters such as frequency, polarization, and look angle as well as the effects of soil moisture on the classification accuracy are also presented

  14. Inhibitory Effect of Corn Silk on Skin Pigmentation

    OpenAIRE

    Sang Yoon Choi; Yeonmi Lee; Sung Soo Kim; Hyun Min Ju; Ji Hwoon Baek; Chul-Soo Park; Dong-Hyuk Lee

    2014-01-01

    In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin prod...

  15. Leaf application of silicic acid to upland rice and corn

    Directory of Open Access Journals (Sweden)

    Carlos Alexandre Costa Crusciol

    2013-12-01

    Full Text Available This study aimed to evaluate the effect of Si (stabilized silicic acid, Silamol® leaf application on mineral nutrition and yield in upland rice and corn crops. The treatments were the control (without Si and Si foliar split spraying using 2 L ha-1 of the Silamol® commercial product, with 0.8% soluble Si as concentrated stabilized silicic acid. Silicon leaf application increased the concentrations of K, Ca and Si in rice and corn leaves, the number of panicles per m2 of rice and the number of grains per ear of corn; accordingly, the Si leaf application provided a higher grain yield in both crops.

  16. Fumonisins B1 and B2 in the corn-milling process and corn-based products, and evaluation of estimated daily intake.

    Science.gov (United States)

    Savi, Geovana D; Piacentini, Karim C; Marchi, Djeini; Scussel, Vildes M

    2016-01-01

    The distribution of fumonisins (FBs: FB1 and FB2) in the corn-milling process and in corn-based products, as well as daily intake estimates for the Brazilian population were evaluated. Among corn fractions samples, corn meal had the highest mean concentration of FB1 (1305 µg kg(-1)) and FB2 (651 µg kg(-1)) and a distribution factors of 452% and 256% in relation to corn grain, respectively. On the other hand, the distribution factor of FB1 and FB2 in corn flour was found to be 144% and 88% respectively, which demonstrates that fumonisins in this fraction were reduced compared with corn grain. As a result, almost half the corn meal samples (47%) would be non-compliant with future Brazilian regulation (2017) for fumonisins. However, corn-based products, such as corn flakes and popcorn, were in compliance with the regulation. The average probable daily intake and maximum probable daily intake of fumonisins estimated for the Santa Catarina state (Brazil) population were below the provisional maximum tolerable daily intake of 2 µg kg(-1) body weight day(-1) for all corn samples. Despite this, the adoption of practices to control the occurrence of fumonisins should be applied to the corn-milling fractions that may contain a higher concentration of this toxin, such as corn meal, often used for animal feed in Brazil.

  17. Effect of the corn breaking method on oil distribution between stillage phases of dry-grind corn ethanol production.

    Science.gov (United States)

    Wang, H; Wang, T; Johnson, L A; Pometto, A L

    2008-11-12

    The majority of fuel ethanol in the United States is produced by using the dry-grind corn ethanol process. The corn oil that is contained in the coproduct, distillers' dried grains with solubles (DDGS), can be recovered for use as a biodiesel feedstock. Oil removal will also improve the feed quality of DDGS. The most economical way to remove oil is considered to be at the centrifugation step for separating thin stillage (liquid) from coarse solids after distilling the ethanol. The more oil there is in the liquid, the more it can be recovered by centrifugation. Therefore, we studied the effects of corn preparation and grinding methods on oil distribution between liquid and solid phases. Grinding the corn to three different particle sizes, flaking, flaking and grinding, and flaking and extruding were used to break up the corn kernel before fermentation, and their effects on oil distribution between the liquid and solid phases were examined by simulating an industrial decanter centrifuge. Total oil contents were measured in the liquid and solids after centrifugation. Dry matter yield and oil partitioning in the thin stillage were highly positively correlated. Flaking slightly reduced bound fat. The flaked and then extruded corn meal released the highest amount of free oil, about 25% compared to 7% for the average of the other treatments. The freed oil from flaking, however, became nonextractable after the flaked corn was ground. Fine grinding alone had little effect on oil partitioning.

  18. Effects of pyrolysis temperature on soybean stover- and peanut shell-derived biochar properties and TCE adsorption in water.

    Science.gov (United States)

    Ahmad, Mahtab; Lee, Sang Soo; Dou, Xiaomin; Mohan, Dinesh; Sung, Jwa-Kyung; Yang, Jae E; Ok, Yong Sik

    2012-08-01

    Conversion of crop residues into biochars (BCs) via pyrolysis is beneficial to environment compared to their direct combustion in agricultural field. Biochars developed from soybean stover at 300 and 700 °C (S-BC300 and S-BC700, respectively) and peanut shells at 300 and 700 °C (P-BC300 and P-BC700, respectively) were used for the removal of trichloroethylene (TCE) from water. Batch adsorption experiments showed that the TCE adsorption was strongly dependent on the BCs properties. Linear relationships were obtained between sorption parameters (K(M) and S(M)) and molar elemental ratios as well as surface area of the BCs. The high adsorption capacity of BCs produced at 700 °C was attributed to their high aromaticity and low polarity. The efficacy of S-BC700 and P-BC700 for removing TCE from water was comparable to that of activated carbon (AC). Pyrolysis temperature influencing the BC properties was a critical factor to assess the removal efficiency of TCE from water. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Legumes and forage species sole or intercropped with corn in soybean-corn succession in midwestern Brazil Espécies leguminosas e forrageiras, solteiras ou consorciadas com milho, na sucessão soja-milho no centro-oeste do Brasil

    Directory of Open Access Journals (Sweden)

    Gessí Ceccon

    2013-02-01

    Full Text Available The feasibility of no-tillage in the Cerrado (Savanna-like vegetation of Brazil depends on the production of sufficient above-ground crop residue, which can be increased by corn-forage intercropping. This study evaluated how above-ground crop residue production and yields of soybean and late-season corn in a soybean-corn rotation were influenced by the following crops in the year before soybean: corn (Zea mays L. intercropped with Brachiaria (Urochloa brizantha cv. Marandu, B. decumbens cv. Basilisk, B. ruziziensis, cv. comum., Panicummaximum cv. Tanzânia, sunn hemp (Crotalaria juncea L., pigeon pea [Cajanus cajan (L. Millsp]; sole corn, forage sorghum [Sorghum bicolor (L. Moench (cv. Santa Elisa], and ruzi grass. In March 2005, corn and forage species were planted in alternate rows spaced 0.90 m apart, and sole forage species were planted in rows spaced 0.45 m apart. In October 2005, the forages were killed with glyphosate and soybean was planted. After the soybean harvest in March 2006, sole late-season corn was planted in the entire experimental area. Corn grain and stover yields were unaffected by intercropping. Above-ground crop residue was greater when corn was intercropped with Tanzania grass (10.7 Mg ha-1, Marandu (10.1 Mg ha-1, and Ruzi Grass (9.8 Mg ha-1 than when corn was not intercropped (4.0 Mg ha-1. The intercropped treatments increased the percentage of soil surface covered with crop residue. Soybean and corn grain yields were higher after sole ruzi grass and intercropped ruzi grass than after other crops. The intercropping corn with Brachiaria spp. and corn with Panicum spp. increases above-ground crop residue production and maintains nutrients in the soil without reducing late-season corn yield and the viability of no-till in the midwestern region of Brazil.A viabilidade do plantio direto no Cerrado brasileiro depende da produção adequada de palha das culturas, que pode ser aumentada pela consorciação de milho (Zea mays L

  20. Transgenic Bt Corn, Soil Insecticide, and Insecticidal Seed Treatment Effects on Corn Rootworm (Coleoptera: Chrysomelidae) Beetle Emergence, Larval Feeding Injury, and Corn Yield in North Dakota.

    Science.gov (United States)

    Calles-Torrez, Veronica; Knodel, Janet J; Boetel, Mark A; Doetkott, Curt D; Podliska, Kellie K; Ransom, Joel K; Beauzay, Patrick; French, B Wade; Fuller, Billy W

    2018-02-09

    Northern, Diabrotica barberi Smith & Lawrence (Coleoptera: Chrysomelidae), and western, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), corn rootworms are economic pests of corn, Zea mays L. in North America. We measured the impacts of corn hybrids incorporated with Cry3Bb1, Cry34/35Ab1, and pyramided (Cry3Bb1 + Cry34/35Ab1) Bacillus thuringiensis Berliner (Bt) proteins, tefluthrin soil insecticide, and clothianidin insecticidal seed treatment on beetle emergence, larval feeding injury, and corn yield at five locations from 2013 to 2015 in eastern North Dakota. In most cases, emergence was significantly lower in Bt-protected corn than in non-Bt corn hybrids. Exceptions included Wyndmere, ND (2013), where D. barberi emergence from Cry34/35Ab1 plots was not different from that in the non-Bt hybrid, and Arthur, ND (2013), where D. v. virgifera emergence from Cry3Bb1 plots did not differ from that in the non-Bt hybrid. Bt hybrids generally produced increased grain yield compared with non-Bt corn where rootworm densities were high, and larval root-feeding injury was consistently lower in Bt-protected plots than in non-Bt corn. The lowest overall feeding injury and emergence levels occurred in plots planted with the Cry3Bb1 + Cry34/35Ab1 hybrid. Time to 50% cumulative emergence of both species was 5-7 d later in Bt-protected than in non-Bt hybrids. Tefluthrin and clothianidin were mostly inconsequential in relation to beetle emergence and larval root injury. Our findings could suggest that some North Dakota populations could be in early stages of increased tolerance to some Bt toxins; however, Bt corn hybrids currently provide effective protection against rootworm injury in eastern North Dakota. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.