WorldWideScience

Sample records for residues corn stover

  1. 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...

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

    Science.gov (United States)

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

  3. 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.

  4. BIOFUEL FROM CORN STOVER

    Directory of Open Access Journals (Sweden)

    Ljiljanka Tomerlin

    2003-12-01

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

  5. 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.

  6. 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

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

    Science.gov (United States)

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

    2018-03-01

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

  8. Spring harvest of corn stover

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-07-01

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

  9. Shock treatment of corn stover.

    Science.gov (United States)

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

    2017-05-01

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

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

    Science.gov (United States)

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

    2018-01-01

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

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

    Science.gov (United States)

    Dooley, James H; Lanning, David N

    2015-04-14

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-01-01

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

  13. 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)

  14. 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.

  15. Moisture Sorption Characteristics of Corn Stover and Big Bluestem

    Directory of Open Access Journals (Sweden)

    C. Karunanithy

    2013-01-01

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

  16. 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.

  17. Reductive Catalytic Fractionation of Corn Stover Lignin

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-12-05

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

  18. Alkaline Peroxide Delignification of Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-05-30

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

  19. Multiscale deconstruction of molecular architecture in corn stover

    Science.gov (United States)

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

    2014-01-01

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

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

    OpenAIRE

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

    2013-01-01

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

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

    Science.gov (United States)

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

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

    Science.gov (United States)

    Kim, Sehoon; Holtzapple, Mark T

    2006-03-01

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

  3. 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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-04-15

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

  5. Delignification kinetics of corn stover in lime pretreatment.

    Science.gov (United States)

    Kim, Sehoon; Holtzapple, Mark T

    2006-03-01

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

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

    Science.gov (United States)

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

    2018-02-27

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

  7. Effect of corn stover concentration on rheological characteristics.

    Science.gov (United States)

    Pimenova, Natalia V; Hanley, Thomas R

    2004-01-01

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

  8. Moisture Sorption Characteristics of Corn Stover and Big Bluestem

    OpenAIRE

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

    2013-01-01

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

  9. 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.

  10. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-01-01

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

  12. 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.

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

    Science.gov (United States)

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

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

    Science.gov (United States)

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

    2014-01-01

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

  15. 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.

  16. 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.

  17. 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...

  18. Fuel ethanol production from alkaline peroxide pretreated corn stover

    Science.gov (United States)

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

  19. 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 ...

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

    NARCIS (Netherlands)

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

    2011-01-01

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

  1. Environmental Impacts of Stover Removal in the Corn Belt

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-08-01

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

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

    Science.gov (United States)

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

    2012-11-01

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

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

    Science.gov (United States)

    Zhang, Jianguo; Hu, Bo

    2014-09-01

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

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

    Science.gov (United States)

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

    2009-08-01

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

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

    Science.gov (United States)

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

    2013-01-01

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

  6. 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...

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

    Science.gov (United States)

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

  8. Soil Hydraulic Properties Influenced by Corn Stover Removal from No-Till Corn in Ohio.

    Energy Technology Data Exchange (ETDEWEB)

    Blanco-Canqui, H.; Lal, Rattan; Post, W. M.; Izaurralde, R Cesar C.; Shipitalo, M. J.

    2007-01-01

    Corn (Zea mays L.) stover removal for biofuel production and other uses may alter soil hydraulic properties, but site-specific information needed to determine the threshold levels of removal for the U.S. Corn Belt region is limited. We quantified impacts of systematic removal of corn stover on soil hydraulic parameters after one year of stover management under no-till (NT) systems in three soils in Ohio including Rayne silt loam (fine-loamy, mixed, mesic Typic Hapludult) at Coshocton, Hoytville clay loam (fine, illitic, mesic Mollic Epiaqualfs) at Hoytville, and Celina silt loam (fine, mixed, active, mesic Aquic Hapludalfs) at South Charleston. Interrelationships among soil properties and saturated hydraulic conductivity (Ksat) predictions were also studied. Earthworm middens, Ksat, bulk density (ρb), soil-water retention (SWR), pore-size distribution, and air permeability (ka) were determined for six stover treatments including 0 (T0), 25 (T25), 50 (T50), 75 (T75), 100 (T100), and 200 (T200) % of corn stover corresponding to 0, 1.25, 2.50, 3.75, 5.00, and 10.00 Mg ha-1 of stover, respectively. Stover removal reduced the number of middens, Ksat, SWR, and ka at all sites (P<0.01). Complete stover removal reduced earthworm middens by 20-fold across sites, decreased geometric mean Ksat from 6.3 to 0.1 mm h-1 at Coshocton, 3.2 to 0.3 mm h-1 at Hoytville, and 5.8 to 0.6 mm h-1 at Charleston, and increased ρb in the 0- to 10-cm depth by about 15% relative to double stover plots. The SWR for T100 was 1.3 times higher than that for T0 at 0 to -6 kPa. The log ka for T200, T100, and T75 significantly exceeded that under T50, T25, and T0 at Coshocton and Charleston. Measured parameters were strongly correlated, and ka was a potential Ksat predictor. Stover harvesting at rates above 1.25 Mg ha-1 affects soil hydraulic properties and earthworm activity, but further monitoring is needed to ascertain the threshold levels of stover removal.Corn (Zea mays L.) stover removal for

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

    Directory of Open Access Journals (Sweden)

    Sarah Rahn

    2012-04-01

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

  10. 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

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. Evaluating corn starch and corn stover biochar as renewable filler in carboxylated styrene-butadiene rubber composites

    Science.gov (United States)

    Corn starch, corn flour, and corn stover biochar were evaluated as potential renewable substitutes for carbon black as filler in rubber composites using carboxylated styrene-butadiene as the rubber matrix. Previous work has shown that starch-based fillers have very good reinforcement properties at t...

  16. 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

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

    Science.gov (United States)

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

    2003-01-01

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

  18. 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...

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

    DEFF Research Database (Denmark)

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

    2018-01-01

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

  20. 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...

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

    Science.gov (United States)

    Kadam, Kiran L; McMillan, James D

    2003-05-01

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

  2. 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.

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

    Science.gov (United States)

    The development of technologies to use cellulosic biomass as a feedstock for biofuel production was recognized as an important research focus because cellulose is a more widely-available feedstock than corn starch. Our objective was to compare various corn (Zea mays L.) stover harvest strategies to ...

  4. 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)

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

    Science.gov (United States)

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

    2014-03-01

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

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

    Directory of Open Access Journals (Sweden)

    Chunyu Liao

    2017-05-01

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

  7. Corn stover fractions as a function of hybrid, maturity, site and year

    Energy Technology Data Exchange (ETDEWEB)

    Lizotte, P.L. [Laval Univ., Quebec City, PQ (Canada). Dept. des sols et de genie agroalimentaire; Savoie, P. [Agriculture and Agri-Food Canada, Quebec City, PQ (Canada); Lefsrud, M. [McGill Univ., Macdonald College, Ste-Anne-de-Bellevue, PQ (Canada). Dept. of Biosystems Engineering

    2010-07-01

    Corn stover is usually left on the ground following corn harvest so that it can be incorporated into the soil as organic matter and to protect against erosion. Part of the corn stover is oxidized in the atmosphere. Corn stover represents between 40 and 50 per cent of the dry matter (DM) contained in the aerial biomass of corn plants. Recent studies have shown that half of the corn stover could be harvested sustainably on low-sloping land under no-till practice. In Quebec, where 400,000 ha of corn are planted each year, corn stover could provide one million t DM of currently neglected biomass. Various hybrids of corn were monitored from early September to late November at 4 different sites during 2007, 2008 and 2009. Whole plants cut at 100 mm above the ground were collected weekly and separated into 7 fractions, notably the grain, the cob, the husk, the stalk below the ear, the stalk above the ear, the leaves below the ear and the leaves above the ear. In 2007, corn ears on average, were at 0.96 m above the ground at a site with low crop heat units (CHU). Hybrids grown in a warmer site were taller and their ears were 1.21 m above the ground. The DM partitioned in 7 components was 54 per cent grain, 14 per cent bottom stalk, 6 per cent top stalk, 5 per cent bottom leaves, 7 per cent top leaves, 5 per cent husk and 9 per cent cob. The total mass of fibre during harvest decreased from 8.9 to 6.6 t DM/ha for a low CHU hybrid and from 9.3 to 8.3 t DM/ha for a high CHU hybrid. Grain yield increased in 2008 from 3.8 to 7.6 t DM/ha over a 12-week period.

  8. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-09-15

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

  10. 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.

  11. 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.

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

    NARCIS (Netherlands)

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

    2017-01-01

    Background: Corn stover is lignocellulosic biomass that has potential to be used as raw material for bioethanol production. In the current research, dilute ammonia pretreatment was used to improve the accessibility of corn stover carbohydrates to subsequently added hydrolytic enzymes. Some

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

    Science.gov (United States)

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

    2014-02-01

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

  14. High solid simultaneous saccharification and fermentation of wet oxidized corn stover to ethanol

    DEFF Research Database (Denmark)

    Varga, E.; Klinke, H.B.; Reczey, K.

    2004-01-01

    In this study ethanol was produced from corn stover pretreated by alkaline and acidic wet oxidation (WO) (195 degreesC, 15 min, 12 bar oxygen) followed by nonisothermal simultaneous saccharification and fermentation (SSF). In the first step of the SSF, small amounts of cellulases were added at 50....../L) were present in the hemicellulose rich hydrolyzate at subinhibitory levels, thus no detoxification was needed prior to SSF of the whole slurry. Based on the cellulose available in the WO corn stover 83% of the theoretical ethanol yield was obtained under optimized SSF conditions. This was achieved...... with a substrate concentration of 12% dry matter (DM) acidic WO corn stover at 30 FPU/g DM (43.5 FPU/g cellulose) enzyme loading. Even with 20 and 15 FPU/g DM (corresponding to 29 and 22 FPU/g cellulose) enzyme loading, ethanol yields of 76 and 73%, respectively, were obtained. After 120 h of SSF the highest...

  15. Improvement of corn stover bioconversion efficiency by using plant glycoside hydrolase.

    Science.gov (United States)

    Han, Yejun; Chen, Hongzhang

    2011-04-01

    Plant cell wall is the most abundant substrate for bioethanol production, and plants also represent a key resource for glycoside hydrolase (GH). To exploit efficient way for bioethanol production with lower cellulase loading, the potential of plant GH for lignocellulose bioconversion was evaluated. The GH activity for cell wall proteins (CWPs) was detected from fresh corn stover (FCS), and the synergism of which with Trichoderma reesei cellulase was also observed. The properties for the GH of FCS make it a promising enzyme additive for lignocellulose biodegradation. To make use of the plant GH, novel technology for hydrolysis and ethanol fermentation was developed with corn stover as substrate. Taking steam-exploded corn stover as substrate for hydrolysis and ethanol fermentation, compared with T. reesei cellulase loaded alone, the final glucose and ethanol accumulation increased by 60% and 63% respectively with GH of FCS as an addition. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. 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.

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

    Directory of Open Access Journals (Sweden)

    Xuezhi Li

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

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

    Science.gov (United States)

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

    2017-01-01

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

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. Enzymatic hydrolysis of pelletized AFEX™-treated corn stover at high solid loadings.

    Science.gov (United States)

    Bals, Bryan D; Gunawan, Christa; Moore, Janette; Teymouri, Farzaneh; Dale, Bruce E

    2014-02-01

    Ammonia fiber expansion (AFEX™) pretreatment can be performed at small depots, and the pretreated biomass can then be pelletized and shipped to a centralized refinery. To determine the feasibility of this approach, pelletized AFEX-treated corn stover was hydrolyzed at high (18-36%) solid loadings. Water absorption and retention by the pellets was low compared to unpelletized stover, which allowed enzymatic hydrolysis slurries to remain well mixed without the need for fed-batch addition. Glucose yields of 68% and xylose yields of 65% were obtained with 20 mg enzyme/g glucan and 18% solid loading after 72 h, compared to 61% and 59% for unpelletized corn stover. Pelletization also slightly increased the initial rate of hydrolysis compared to unpelletized biomass. The ease of mixing and high yields obtained suggests that pelletization after AFEX pretreatment could have additional advantages beyond improved logistical handling of biomass. © 2013 Wiley Periodicals, Inc.

  4. 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

  5. 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

  6. A Five-Year Assessment of Corn Stover Harvest in Central Iowa, USA

    Energy Technology Data Exchange (ETDEWEB)

    Douglas L. Karlen; Stuart J. Birell; J. Richard Hess

    2011-11-01

    Sustainable feedstock harvest strategies are needed to ensure bioenergy production does not irreversibly degrade soil resources. The objective for this study was to document corn (Zea mays L.) grain and stover fraction yields, plant nutrient removal and replacement costs, feedstock quality, soil-test changes, and soil quality indicator response to four stover harvest strategies for continuous corn and a corn-soybean [Glycine max. (L.) Merr.] rotation. The treatments included collecting (1) all standing plant material above a stubble height of 10 cm (whole plant), (2) the upper-half by height (ear shank upward), (3) the lower-half by height (from the 10 cm stubble height to just below the earshank), or (4) no removal. Collectable biomass from Treatment 2 averaged 3.9 ({+-}0.8) Mg ha{sup -1} for continuous corn (2005 through 2009), and 4.8 ({+-}0.4) Mg ha{sup -1} for the rotated corn (2005, 2007, and 2009). Compared to harvesting only the grain, collecting stover increased the average N-P-K removal by 29, 3 and 34 kg ha{sup -1} for continuous corn and 42, 3, and 34 kg ha{sup -1} for rotated corn, respectively. Harvesting the lower-half of the corn plant (Treatment 3) required two passes, resulted in frequent plugging of the combine, and provided a feedstock with low quality for conversion to biofuel. Therefore, Treatment 3 was replaced by a 'cobs-only' harvest starting in 2009. Structural sugars glucan and xylan accounted for up to 60% of the chemical composition, while galactan, arabinan, and mannose constituted less than 5% of the harvest fractions collected from 2005 through 2008. Soil-test data from samples collected after the first harvest (2005) revealed low to very low plant-available P and K levels which reduced soybean yield in 2006 after harvesting the whole-plant in 2005. Average continuous corn yields were 21% lower than rotated yields with no significant differences due to stover harvest. Rotated corn yields in 2009 showed some significant

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

    Science.gov (United States)

    M.R. Ehrhardt; T.O. Monz; T.W. Root; R.K. Connelly; Tim Scott; D.J. Klingenberg

    2010-01-01

    The rheological properties of acid hydrolyzed corn stover at high solids concentration (20–35 wt.%) were investigated using torque rheometry. These materials are yield stress fluids whose rheological properties can be well represented by the Bingham model. Yield stresses increase with increasing solids concentration and decrease with increasing hydrolysis reaction...

  8. 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...

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

    DEFF Research Database (Denmark)

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

    2010-01-01

    Hydrothermal pretreatment on raw corn stover (RCS) with a loop reactor was investigated at 195 °C for different times varying between 10 min and 30 min. After pretreatment, the slurry was separated into water-insoluble solid (WIS) and liquid phase. Glucan and xylan were found in the both phases...

  10. Investigation of acetic acid-catalyzed hydrothermal pretreatment on corn stover

    DEFF Research Database (Denmark)

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

    2010-01-01

    Acetic acid (AA)-catalyzed liquid hot water (LHW) pretreatments on raw corn stover (RCS) were carried out at 195 °C at 15 min with the acetic acid concentrations between 0 and 400 g/kg RCS. After pretreatment, the liquor fractions and water-insoluble solids (WIS) were collected separately and tes...

  11. 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...

  12. Effect of treatment and cultivar on the ensiling of corn stover

    Science.gov (United States)

    Nine cultivars of corn stover selected for ethanol potential were harvested (34 to 40% dry matter) and each ensiled with six treatments: untreated, lactic acid bacteria, cell-wall degrading enzymes, sulfuric acid, bacteria-enzyme combination and enzyme-acid combination. Ensiling was carried out in v...

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

    Science.gov (United States)

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

    2015-03-01

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

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

    DEFF Research Database (Denmark)

    Varga, E.; Schmidt, A.S.; Reczey, K.

    2003-01-01

    Corn stover is an abundant, promising raw material for fuel ethanol production. Although it has a high cellulose content, without pretreatment it resists enzymatic hydrolysis, like most lignocellulosic materials. Wet oxidation (water, oxygen, mild alkali or acid, elevated temperature and pressure...

  15. 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...

  16. 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.

  17. Optimization of dilute sulfuric acid pretreatment and enzymatic saccharification of corn stover for efficient ethanol production

    Science.gov (United States)

    Dilute acid pretreatment is a promising pretreatment technology for conversion of lignocellulosic biomass to fuel ethanol. Corn stover (supplied by a local farmer) used in this study contained 37.0±0.4% cellulose, 31.3±0.6% hemicelluloses, and 17.8±0.2% lignin. Generation of fermentable sugars from ...

  18. 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.

  19. 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.

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

    Science.gov (United States)

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

    2016-01-01

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

  1. 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.

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

    Science.gov (United States)

    Wendt, Lynn M.; Murphy, J. Austin; Smith, William A.; Robb, Thomas; Reed, David W.; Ray, Allison E.; Liang, Ling; He, Qian; Sun, Ning; Hoover, Amber N.; Nguyen, Quang A.

    2018-01-01

    Wet anaerobic storage of corn stover can provide a year-round supply of feedstock to biorefineries meanwhile serving an active management approach to reduce the risks associated with fire loss and microbial degradation. Wet logistics systems employ particle size reduction early in the supply chain through field-chopping which removes the dependency on drying corn stover prior to baling, expands the harvest window, and diminishes the biorefinery size reduction requirements. Over two harvest years, in-field forage chopping was capable of reducing over 60% of the corn stover to a particle size of 6 mm or less. Aerobic and anaerobic storage methods were evaluated for wet corn stover in 100 L laboratory reactors. Of the methods evaluated, traditional ensiling resulted in biofuel production. Evaluation of the operational efficiencies and costs is suggested to quantify the potential benefits of a fully-wet biomass supply system to a commercial biorefinery. PMID:29632861

  3. 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.

  4. 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.

  5. 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

  6. 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%.

  7. 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.

  8. 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

  9. 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.

  10. 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...

  11. 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.

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

    Science.gov (United States)

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

    2014-03-25

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

  13. 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.

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

    Science.gov (United States)

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

    2012-08-01

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

  15. 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.

  16. 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.

  17. 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.

  18. 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.

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

    Science.gov (United States)

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

    2017-03-01

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

  20. 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.

  1. 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

  2. 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-...

  3. 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...

  4. High solid simultaneous saccharification and fermentation of wet oxidized corn stover to ethanol.

    Science.gov (United States)

    Varga, Enikõ; Klinke, Helene B; Réczey, Kati; Thomsen, Anne Belinda

    2004-12-05

    In this study ethanol was produced from corn stover pretreated by alkaline and acidic wet oxidation (WO) (195 degrees C, 15 min, 12 bar oxygen) followed by nonisothermal simultaneous saccharification and fermentation (SSF). In the first step of the SSF, small amounts of cellulases were added at 50 degrees C, the optimal temperature of enzymes, in order to obtain better mixing condition due to some liquefaction. In the second step more cellulases were added in combination with dried baker's yeast (Saccharomyces cerevisiae) at 30 degrees C. The phenols (0.4-0.5 g/L) and carboxylic acids (4.6-5.9 g/L) were present in the hemicellulose rich hydrolyzate at subinhibitory levels, thus no detoxification was needed prior to SSF of the whole slurry. Based on the cellulose available in the WO corn stover 83% of the theoretical ethanol yield was obtained under optimized SSF conditions. This was achieved with a substrate concentration of 12% dry matter (DM) acidic WO corn stover at 30 FPU/g DM (43.5 FPU/g cellulose) enzyme loading. Even with 20 and 15 FPU/g DM (corresponding to 29 and 22 FPU/g cellulose) enzyme loading, ethanol yields of 76 and 73%, respectively, were obtained. After 120 h of SSF the highest ethanol concentration of 52 g/L (6 vol.%) was achieved, which exceeds the technical and economical limit of the industrial-scale alcohol distillation. The SSF results showed that the cellulose in pretreated corn stover can be efficiently fermented to ethanol with up to 15% DM concentration. A further increase of substrate concentration reduced the ethanol yield significant as a result of insufficient mass transfer. It was also shown that the fermentation could be followed with an easy monitoring system based on the weight loss of the produced CO2.

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

    Science.gov (United States)

    Darvekar, Pratik; Holtzapple, Mark T

    2016-03-01

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

  6. 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.

  7. Pretreatment of corn stover with diluted acetic acid for enhancement of acidogenic fermentation.

    Science.gov (United States)

    Zhao, Xu; Wang, Lijuan; Lu, Xuebin; Zhang, Shuting

    2014-04-01

    A Box-Behnken design of response surface method was used to optimize acetic acid-catalyzed hydrothermal pretreatment of corn stover, in respect to acid concentration (0.05-0.25%), treatment time (5-15 min) and reaction temperature (180-210°C). Acidogenic fermentations with different initial pH and hydrolyzates were also measured to evaluate the optimal pretreatment conditions for maximizing acid production. The results showed that pretreatment with 0.25% acetic acid at 191°C for 7.74 min was found to be the most optimal condition for pretreatment of corn stover under which the production of acids can reach the highest level. Acidogenic fermentation with the hydrolyzate of pretreatment at the optimal condition at the initial pH=5 was shown to be butyric acid type fermentation, producing 21.84 g acetic acid, 7.246 g propionic acid, 9.170 butyric acid and 1.035 g isovaleric acid from 100g of corn stover in 900 g of water containing 2.25 g acetic acid. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-02-01

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

  9. Mathematical model parameters for describing the particle size spectra of knife-milled corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Bitra, V.S.P [University of Tennessee; Womac, A.R. [University of Tennessee; Yang, Y.T. [University of Tennessee; Miu, P.I. [University of Tennessee; Igathanathane, C. [Mississippi State University (MSU)

    2009-09-01

    Particle size distributions of Corn stover (Zea mays L.) created by a knife mill were determined using integral classifying screens with sizes from 12.7 to 50.8 mm, operating at speeds from 250 to 500 rpm, and mass input rates ranging from 1 to 9 kg min_1. Particle distributions were classified using American Society of Agricultural and Biological Engineers (ASABE) standardised sieves for forage analysis that incorporated a horizontal sieving motion. The sieves were made from machined-aluminium with their thickness proportional to the sieve opening dimensions. A wide range of analytical descriptors that could be used to mathematically represent the range of particle sizes in the distributions were examined. The correlation coefficients between geometric mean length and screen size, feed rate, and speed were 0.980, 0.612, and _0.027, respectively. Screen size and feed rate directly influenced particle size, whereas operating speed had a weak indirect relation with particle size. The Rosin Rammler equation fitted the chopped corn stover size distribution data with coefficient of determination (R2) > 0.978. This indicated that particle size distribution of corn stover was well-fit by the Rosin Rammler function. This can be attributed to the fact that Rosin Rammler expression was well suited to the skewed distribution of particle sizes. Skewed distributions occurred when significant quantities of particles, either finer or coarser, existed or were removed from region of the predominant size. The mass relative span was slightly greater than 1, which indicated that it was a borderline narrow to wide distribution of particle sizes. The uniformity coefficient was <4.0 for 19.0 50.8 mm screens, which indicated particles of relatively uniform size. Knife mill chopping of corn stover produced fine-skewed mesokurtic particles with 12.7 50.8 mm screens. Size-related parameters, namely, geometric mean length, Rosin Rammler size parameter, median length, effective length, and

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

    Science.gov (United States)

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

    2011-05-01

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

  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 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.

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

    Science.gov (United States)

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

    2010-08-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-05-01

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

  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. 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. Degradation of corn stover by fungal cellulase cocktail for production of polyhydroxyalkanoates by moderate halophile Paracoccus sp. LL1.

    Science.gov (United States)

    Sawant, Shailesh S; Salunke, Bipinchandra K; Kim, Beom Soo

    2015-10-01

    Bioprocessing of lignocellulose as a renewable resource for fuels, chemicals or value added products is a necessity to fulfil demands of petroleum products. This study aims to convert corn stover to polyhydroxyalkanoates (PHA). Corn stover was hydrolyzed to crude sugars by an on-site prepared cellulase cocktail from co-culture of Trichoderma reesei and Aspergillus niger. The potent PHA producer, Paracoccus sp. LL1, was isolated from Lonar Lake, India and could accumulate PHA up to 72.4% of its dry cell weight. PHA production reached 9.71 g/L from corn stover hydrolysate containing 40 g/L sugar mixture. The PHA synthase gene (phaC) sequence of the isolate showed 79% identity with the phaC gene of Paracoccus seriniphilus (E71) strain from the NCBI database. The nature/type of PHA was found to be poly(3-hydroxybutyrate) by Fourier transform infrared spectroscopy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. 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.

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

    Directory of Open Access Journals (Sweden)

    Lynn M. Wendt

    2018-03-01

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

  19. The Impact of Enzyme Characteristics on Corn Stover Fiber Degradation and Acid Production During Ensiled Storage

    Science.gov (United States)

    Ren, Haiyu; Richard, Tom L.; Moore, Kenneth J.

    Ensilage can be used to store lignocellulosic biomass before industrial bioprocessing. This study investigated the impacts of seven commerical enzyme mixtures derived from Aspergillus niger, Trichoderma reesei, and T. longibrachiatum. Treatments included three size grades of corn stover, two enzyme levels (1.67 and 5 IU/g dry matter based on hemicellulase), and various ratios of cellulase to hemicellulase (C ∶ H). The highest C ∶ H ratio tested, 2.38, derived from T. reesei, resulted in the most effective fermentation, with lactic acid as the dominant product. Enzymatic activity during storage may complement industrial pretreatment; creating synergies that could reduce total bioconversion costs.

  20. Systematics of corn stover pyrolysis yields and comparisons of analytical and kinetic representations

    Energy Technology Data Exchange (ETDEWEB)

    Green, Alex E.S. [Clean Combustion Technology Laboratory, University of Florida, Gainesville, FL 32611-6550 (United States); Feng, Jie [Key Laboratory of Coal Science and Technology, Taiyuan University of Technology, Taiyuan, Shanxi 030024 (China)

    2006-06-01

    This paper focuses on the systematics of a large body of experimental corn stover pyrolysis yields measured with a Pyroprobe-FTIR system at Taiyuan University of Technology (TUT) using a wide range of heating rates, This large body of data is organized using an analytical semi-empirical model (ASEM) developed at the University of Florida that provides a reasonable account using only a small number of adjusted parameters. The data is also organized with a traditional kinetic model (Arrhenius reaction rates) and comparisons are made between the two models from the viewpoint of engineering applications of pyrolysis. (author)

  1. 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.

  2. 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.

  3. 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.

  4. Synergistic Enhancement of Cellobiohydrolase Performance on Pretreated Corn Stover by Addition of Xylanase and Esterase Activities

    Energy Technology Data Exchange (ETDEWEB)

    Selig, M. J.; Knoshaug E. P.; Adney, W. S.; Himmel, M. E.; Decker, S. R.

    2007-11-01

    Significant increases in the depolymerization of corn stover cellulose by cellobiohydrolase I (Cel7A) from Trichoderma reesei were observed using small quantities of non-cellulolytic cell wall-degrading enzymes. Purified endoxylanase (XynA), ferulic acid esterase (FaeA), and acetyl xylan esterase (Axe1) all enhanced Cel7A performance on corn stover subjected to hot water pretreatment. In all cases, the addition of these activities improved the effectiveness of the enzymatic hydrolysis in terms of the quantity of cellulose converted per milligram of total protein. Improvement in cellobiose release by the addition of the non-cellulolytic enzymes ranged from a 13-84% increase over Cel7A alone. The most effective combinations included the addition of both XynA and Axe1, which synergistically enhance xylan conversions resulting in additional synergistic improvements in glucan conversion. Additionally, we note a direct relationship between enzymatic xylan removal in the presence of XynA and the enhancement of cellulose hydrolysis by Cel7A.

  5. 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.

  6. 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.

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

    Science.gov (United States)

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

    2014-01-01

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

  8. Response surface methodology (RSM) to evaluate moisture effects on corn stover in recovering xylose by DEO hydrolysis

    Science.gov (United States)

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

    2012-01-01

    Response surface methodology (RSM), based on a 22 full factorial design, evaluated the moisture effects in recovering xylose by diethyloxalate (DEO) hydrolysis. Experiments were carried out in laboratory reactors (10 mL glass ampoules) containing corn stover (0.5 g) properly ground. The ampoules were kept at 160 °C for 90 min. Both DEO...

  9. Biological pretreatment of corn stover with Phlebia brevispora NRRL-13108 for enhanced enzymatic hydrolysis and efficient ethanol production

    Science.gov (United States)

    Biological pretreatment of lignocellulosic biomass by white-rot fungus can represent a low-cost and eco-friendly alternative to harsh physical, chemical, or physico-chemical pretreatment methods to facilitate enzymatic hydrolysis. In this work, solid state cultivation of corn stover with Phlebia bre...

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

    Science.gov (United States)

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

    2014-07-01

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

  11. Chemical properties and antioxidant activity of exopolysaccharides fractions from mycelial culture of Inonotus obliquus in a ground corn stover medium.

    Science.gov (United States)

    Xiang, Yuling; Xu, Xiangqun; Li, Juan

    2012-10-15

    The medicinal mushroom Inonotus obliquus has been a folk remedy for a long time in East-European and Asian countries. We first reported the enhancement in production and antioxidant activity of exopolysaccharides by I. obliquus culture under lignocellulose decomposition. In this study, the two different sources of exopolysaccharides from the control medium and the lignocellulose (corn stover) containing medium by I. obliquus in submerged fermentation were fractionated and purified by chromatography. The exopolysaccharides from the corn stover-containing medium presented significantly stronger hydroxyl and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity than the control. Three fractions from the control medium and the corn stover-containing medium were isolated respectively. The fraction of DEPL3 from the corn stover-containing medium with the highest protein content (38.3%), mannose content (49.6%), and the lowest molecular weight (29 kDa) had the highest antioxidant activity with the lowest IC50 values. In conclusion, lignocellulose decomposition changed the chemical characterisation and significantly enhanced the antioxidant activity of exopolysaccharide fractions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. 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)

  13. Cellulase adsorption and relationship to features of corn stover solids produced by leading pretreatments.

    Science.gov (United States)

    Kumar, Rajeev; Wyman, Charles E

    2009-06-01

    Although essential to enzymatic hydrolysis of cellulosic biomass to sugars for fermentation to ethanol or other products, enzyme adsorption and its relationship to substrate features has received limited attention, and little data and insight have been developed on cellulase adsorption for promising pretreatment options, with almost no data available to facilitate comparisons. Therefore, adsorption of cellulase on Avicel, and of cellulase and xylanase on corn stover solids resulting from ammonia fiber expansion (AFEX), ammonia recycled percolation (ARP), controlled pH, dilute acid, lime, and sulfur dioxide (SO(2)) pretreatments were measured at 4 degrees C. Langmuir adsorption parameters were then estimated by non-linear regression using Polymath software, and cellulase accessibility to cellulose was estimated based on adsorption data for pretreated solids and lignin left after carbohydrate digestion. To determine the impact of delignification and deacetylation on cellulose accessibility, purified CBHI (Cel7A) adsorption at 4 degrees C and hydrolysis with whole cellulase were followed for untreated (UT) corn stover. In all cases, cellulase attained equilibrium in less than 2 h, and upon dilution, solids pretreated by controlled pH technology showed the greatest desorption followed by solids from dilute acid and SO(2) pretreatments. Surprisingly, the lowest desorption was measured for Avicel glucan followed by solids from AFEX pretreatment. The higher cellulose accessibility for AFEX and lime pretreated solids could account for the good digestion reported in the literature for these approaches. Lime pretreated solids had the greatest xylanase capacity and AFEX solids the least, showing pretreatment pH did not seem to be controlling. The 24 h glucan hydrolysis rate data had a strong relationship to cellulase adsorption capacities, while 24 h xylan hydrolysis rate data showed no relationship to xylanase adsorption capacities. Furthermore, delignification greatly

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

    Directory of Open Access Journals (Sweden)

    Julierme Zimmer Barbosa

    Full Text Available ABSTRACT Changes in quantity and quality of corn crop stover can have a large impact on soil conservation and soil carbon (C sequestration over large areas. The aim of this study was to evaluate changes in production, concentration and amount of C and nitrogen (N in corn stover fractions due to cultivar development. Two field experiments were conducted in the city of Rolândia (Paraná State, Brazil using ten cultivars representing five technological levels: single cross hybrids, double or triple hybrids, commercial varieties, and creole cultivars. Plant heights and stalk, leaf, cob, husk and tassel weights were determined at final harvest. Elemental C and N analyses were performed in triplicate for each stover fraction. In general, the creole cultivars had greater height, more dry matter (kg ha-1 and C content (kg ha-1 in husks, leaves, tassels and stalks, particularly when compared to single cross hybrids or others hybrids. There was a direct relationship between C/N ratio and corn selection for husks in both years and for the others fractions in one study year. This was due to the combined effects of increasing C and decreasing N due to crop selection. Large differences were observed within the same technological levels for the evaluated properties, suggesting a wide variation in genetic background. The quantity and quality of stover fractions vary among cultivars and may affect their use for soil cover, animal feed, biomass energy and other applications.

  15. Tween 40 pretreatment of unwashed water-insoluble solids of reed straw and corn stover pretreated with liquid hot water to obtain high concentrations of bioethanol.

    Science.gov (United States)

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

    2013-11-09

    Liquid hot water (LHW) pretreatment is an effective and environmentally friendly method to produce bioethanol with lignocellulosic materials. In our previous study, high ethanol concentration and ethanol yield were obtained from water-insoluble solids (WIS) of reed straw and corn stover pretreated with LHW by using fed-batch semi-simultaneous saccharification and fermentation (S-SSF). However, high cellulase loading and the large amount of wash water possibly limit the practical application of LHW pretreatment. To decrease cellulase loading and the amount of wash water, we performed Tween 40 pretreatment before WIS was subjected to bioethanol fermentation. Results showed that the optimum conditions of Tween 40 pretreatment were as follows: Tween 40 concentration of 1.5%, WIS-to-Tween 40 ratio of 1:10 (w/v), and pretreatment time of 1 hour at ambient temperature. After Tween 40 pretreatment, cellulase loading could be greatly reduced. After Tween 40 pretreatment, the residual liquid could be recycled for utilization but slightly affected ethanol concentration and yield. The unwashed WIS could obtain a high ethanol concentration of 56.28 g/L (reed straw) and 52.26 g/L (corn stover) by Tween 40 pretreatment using fed-batch S-SSF. Ethanol yield reached a maximum of 69.1% (reed straw) and 71.1% (corn stover). Tween 40 pretreatment was a very effective and less costly method with unwashed WIS. This pretreatment could greatly reduce cellulase loading and save wash water. Higher ethanol concentration was obtained almost without reducing ethanol yield.

  16. Yield stress of pretreated corn stover suspensions using magnetic resonance imaging.

    Science.gov (United States)

    Lavenson, David M; Tozzi, Emilio J; McCarthy, Michael J; Powell, Robert L

    2011-10-01

    Cellulose fibers in water form networks that give rise to an apparent yield stress, especially at high solids contents. Measuring the yield stress and correlating it with fiber concentration is important for the biomass and pulp industries. Understanding how the yield stress behaves at high solids concentrations is critical to optimize enzymatic hydrolysis of biomass in the production of biofuels. Rheological studies on pretreated corn stover and various pulp fibers have shown that yield stress values correlate with fiber mass concentration through a power-law relationship. We use magnetic resonance imaging (MRI) as an in-line rheometer to measure velocity profiles during pipe flow. If coupled with pressure drop measurements, these allow yield stress values to be determined. We compare our results with literature values and discuss the accuracy and precision of the rheo-MRI measurement, along with the effects of fiber characteristics on the power-law coefficients. Copyright © 2011 Wiley Periodicals, Inc.

  17. Assessment and regression analysis on instant catapult steam explosion pretreatment of corn stover.

    Science.gov (United States)

    Liu, Chen-Guang; Liu, Li-Yang; Zi, Li-Han; Zhao, Xin-Qing; Xu, You-Hai; Bai, Feng-Wu

    2014-08-01

    Instant catapult steam explosion (ICSE) offers enormous physical force on lignocellulosic biomass due to its extremely short depressure duration. In this article, the response surface methodology was applied to optimize the effect of working parameters including pressure, maintaining time and mass loading on the crystallinity index and glucose yield of the pretreated corn stover. It was found that the pressure was of essential importance, which determined the physical force that led to the morphological changes without significant chemical reactions, and on the other hand the maintaining time mainly contributed to the thermo-chemical reactions. Furthermore, the pretreated biomass was assessed by scanning electron microscope, X-ray diffraction and Fourier transform infrared spectra to understand mechanisms underlying the ICSE pretreatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. 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...... batch SSF, prehydrolysis followed by batch SSF and fed-batch SSF. Batch-SSF resulted in an ethanol yield of 75-76% and an ethanol concentration of 53 g/L. Prehydrolysis prior to batch SSF did not improve the ethanol yield compared with batch SSF. Fedbatch SSF, on the other hand, increased the yield...... was seen in batch mode with and without prehydrolysis (73%). This resulted in similar ethanol yields in all methods. However, the residence time to achieve the final ethanol yield was shorter using fed-batch. This shows that fed-batch can be a better alternative also at a lower enzyme loading....

  19. 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.

  20. Correlating Detergent Fiber Analysis and Dietary Fiber Analysis Data for Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Wolfrum, E. J.; Lorenz, A. J.; deLeon, N.

    2009-01-01

    There exist large amounts of detergent fiber analysis data [neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL)] for many different potential cellulosic ethanol feedstocks, since these techniques are widely used for the analysis of forages. Researchers working in the area of cellulosic ethanol are interested in the structural carbohydrates in a feedstock (principally glucan and xylan), which are typically determined by acid hydrolysis of the structural fraction after multiple extractions of the biomass. These so-called dietary fiber analysis methods are significantly more involved than detergent fiber analysis methods. The purpose of this study was to determine whether it is feasible to correlate detergent fiber analysis values to glucan and xylan content determined by dietary fiber analysis methods for corn stover. In the detergent fiber analysis literature cellulose is often estimated as the difference between ADF and ADL, while hemicellulose is often estimated as the difference between NDF and ADF. Examination of a corn stover dataset containing both detergent fiber analysis data and dietary fiber analysis data predicted using near infrared spectroscopy shows that correlations between structural glucan measured using dietary fiber techniques and cellulose estimated using detergent techniques, and between structural xylan measured using dietary fiber techniques and hemicellulose estimated using detergent techniques are high, but are driven largely by the underlying correlation between total extractives measured by fiber analysis and NDF/ADF. That is, detergent analysis data is correlated to dietary fiber analysis data for structural carbohydrates, but only indirectly; the main correlation is between detergent analysis data and solvent extraction data produced during the dietary fiber analysis procedure.

  1. 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.

  2. 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

  3. The promoting effects of manganese on biological pretreatment with Irpex lacteus and enzymatic hydrolysis of corn stover.

    Science.gov (United States)

    Song, Lili; Ma, Fuying; Zeng, Yelin; Zhang, Xiaoyu; Yu, Hongbo

    2013-05-01

    The effect of metal ions on biological pretreatment was evaluated for improving subsequent enzymatic hydrolysis. Results showed that the efficiency of fungal pretreatment was greatly improved with manganese supplement in biomass. After enzymatic hydrolysis of 28-d pretreated corn stover, maximum glucose yield was 308.98 mg/g corn stover with manganese supplement, which increased by 61.39% as compared to the conventional fungal pretreatment. Furthermore, manganese also enhanced the production of ethanol, corresponding to a high ethanol conversion (83.39%). Manganese greatly improved the delignification of Irpex lacteus specially. Correspondingly, the efficiency of saccharification and fermentation was closely related to the removal of lignin. This study showed a promising effect of manganese on fungal pretreatment and the production of biofuels. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. 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.

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

    Science.gov (United States)

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

    2014-02-01

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

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

    Science.gov (United States)

    Diallo, Oumou

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

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

    Science.gov (United States)

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

    2012-09-01

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

  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. 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

  10. 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.

  11. Improvement of sugar yields from corn stover using sequential hot water pretreatment and disk milling.

    Science.gov (United States)

    Kim, Sun Min; Dien, Bruce S; Tumbleson, M E; Rausch, Kent D; Singh, Vijay

    2016-09-01

    Efficient pretreatment is essential for economic conversion of lignocellulosic feedstocks into monosaccharides for biofuel production. To realize high sugar yields with low inhibitor concentrations, hot water or dilute acid pretreatment followed by disk milling is proposed. Corn stover at 20% solids was pretreated with hot water at 160-200°C for 4-8min with and without subsequent milling. Hot water pretreatment and disk milling acted synergistically to improve glucose and xylose yields by 89% and 134%, respectively, compared to hot water pretreatment alone. Hot water pretreated (180°C for 4min) and milled samples had the highest glucose and xylose yields among all hot water pretreated and milled samples, which were comparable to samples pretreated with 0.55% dilute acid at 160°C for 4min. However, samples pretreated with 1% dilute acid at 150°C for 4min and disk milled had the highest observed glucose (87.3%) and xylose yields (83.4%). Copyright © 2016. Published by Elsevier Ltd.

  12. Fuel ethanol production from wet oxidised corn stover by S. cerevisiae

    DEFF Research Database (Denmark)

    Qiang, zhang; Thomsen, Anne Belinda

    2012-01-01

    of 74.6% were obtained after pretreatment. 86.5% of cellulose was remained in the solid cake. After 24h hydrolysis at 50°C using cellulase (Cellubrix L), the achieved conversion of cellulose to glucose was 64.8%. Ethanol production was evaluated from dried solid cake and the hydrolysate was employed......In order to find out appropriate process for ethanol production from corn stover, wet oxidation (195°C, 15 minutes) and simultaneous saccharification and fermentation (SSF) was carried out to produce ethanol. The results showed that the cellulose recovery of 92.9% and the hemicellulose recovery...... as liquid fraction. After 142 h of SSF with substrate concentration of 8% (W/V), ethanol yield of 73.1 % of the theoretical based on glucose in the raw material was obtained by S. cerevisiae(ordinary baker' yeast). The corresponding ethanol concentration and volumetric productivity were 17.2g/L and 0.121g...

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. Comparison of different pretreatments for the production of bioethanol and biomethane from corn stover and switchgrass.

    Science.gov (United States)

    Papa, G; Rodriguez, S; George, A; Schievano, A; Orzi, V; Sale, K L; Singh, S; Adani, F; Simmons, B A

    2015-05-01

    In this study the efficiency of mild ionic liquid (IL) pretreatment and pressurized hot water (PHW) is evaluated and compared in terms of bioethanol and biomethane yields, with corn stover (CS) and switchgrass (SG) as model bioenergy crops. Both feedstocks pretreated with the IL 1-ethyl-3-methylimidazolium acetate [C2C1Im][OAc] at 100°C for 3h exhibited lower glucose yield that those treated with harsher pretreatment conditions previously used. Compared to PHW, IL pretreatment demonstrated higher bioethanol yields; moreover IL pretreatment enhanced biomethane production. Taking into consideration both bioethanol and biomethane productions, results indicated that when using IL pretreatment, the total energy produced per kg of total solids was higher compared to untreated biomasses. Specifically energy produced from CS and SG was +18.6% and +34.5% respectively, as compared to those obtained by hot water treatment, i.e. +2.3% and +23.4% for CS and SG, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Enhanced bioethanol production from pretreated corn stover via multi-positive effect of casein micelles.

    Science.gov (United States)

    Eckard, Anahita Dehkhoda; Muthukumarappan, Kasiviswanathan; Gibbons, William

    2013-05-01

    Casein polypeptides containing substructures of αs1-casein, β-casein, k-casein, αs2-casein were used as a lignin-blocker at above critical micelles concentration to improve the bioethanol production of dilute acid, lime, alkali, extrusion and AFEX pretreated corn stover (CS). Application of 0.5 g/g glucan of casein was found to effectively increase the glucose yield of CS pretreated with dilute acid, lime, alkali, extrusion and AFEX by 31.9%, 17.0%, 22.7%, 29.5%, and 17.4%, respectively with no positive impact on Avicel. Consequently 96 h simultaneous saccharification and fermentation (SSF) of these hydrolysates reduced the fermentation period by up to 48 h and increased the theoretical yield of ethanol by 8.48-33.7% compared to control. Application of casein during saccharification reduced the enzyme utilization by 33.0%. Recycling of hydrolysate from casein-treated CS for a 2nd round hydrolysis resulted in average glucose yield of 36.4% compared to 29.0% control. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Proteolysis, fermentation efficiency, and in vitro ruminal digestion of peanut stover ensiled with raw or heated corn.

    Science.gov (United States)

    Yang, C-M J

    2005-08-01

    Peanut stover (PS) is similar to full-bloom alfalfa hay in chemical composition. The objective of this study was to assess the effect of adding raw or heated corn meal to PS at ensiling on silage N components, fermentation acids, and digestion by ruminal microorganisms. The PS was collected after harvesting of peanuts and ensiled immediately without and with addition of raw or heated corn meal (100 g/kg of fresh weight). Corn was added to PS so that the initial mixture would contain adequate dry matter (DM) (approximately 30%) and additional nonfiber carbohydrate to enhance silage fermentation. After 8 wk of silo fermentation, corn-treated silages contained less structural carbohydrates but more non-fiber carbohydrates compared with the untreated control. A shift from hemicellulose to nonfiber carbohydrate use during silage fermentation was evident by corn treatment. Additional corn at ensiling resulted in silage N with less water-soluble N, protein N, nonprotein N, nonprotein nonammonia N (peptides plus amino acids), and ammonia N. Based on changes in soluble nonprotein N before and after ensiling, the amount of proteolysis was approximately 66% for control silage and was nearly 40% lower in response to corn treatment. Adding corn increased silage lactic acid, but both acetic and propionic acids decreased. These changes were reflected in the lower pH and higher fermentation efficiency with corn-treated silages. More DM was digested and greater amounts of volatile fatty acids, except for branched-chain acids, were produced in vitro by ruminal microorganisms with corn-treated silages. In addition, incubations with silage treated with heated corn contained higher concentrations of acetic and propionic acids compared with raw corn. In vitro ammonia accumulation per unit of DM digested was lower for corn treatments than the control, and for heated corn vs. raw corn-treated silage. These results indicate that supplementation of either raw or heated corn on PS at

  1. 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.

  2. Conservation characteristics of corn ears and stover ensiled with the addition of Lactobacillus plantarum MTD-1, Lactobacillus plantarum 30114, or Lactobacillus buchneri 11A44.

    Science.gov (United States)

    Lynch, J P; O'Kiely, P; Waters, S M; Doyle, E M

    2012-04-01

    The aim of this study was to investigate the effects of inoculating 3 contrasting lactic acid bacteria on the fermentation profile, estimated nutritive value, and aerobic stability of corn ears and stover produced under marginal growing conditions. Ears and stover were separated from whole-crop corn plants obtained from 3 replicate field blocks. Representative subsamples were precision chopped and allocated to 1 of the following treatments: an uninoculated control, Lactobacillus plantarum MTD-1 (LP1), L. plantarum 30114 (LP2), or Lactobacillus buchneri 11A44 (LB). Each bacterial additive was applied at a rate of 1 × 10(6) cfu/g of fresh herbage. Triplicate samples of each treatment were ensiled in laboratory silos at 15°C for 3, 10, 35, or 130 d. No difference was observed between the dry matter recoveries of uninoculated ear or stover silages and silages made with LP1, and the aerobic stability of uninoculated ear and stover silages did not differ from silages made with LB. Stover silages made with LP2 and ensiled for 35 d had a lower proportion of lactic acid in total fermentation products compared with LP1. The aerobic stability and dry matter recovery of ear and stover silages in this study were not improved when made with LB, LP1, or LP2, due to the indigenous highly heterolactic fermentation that prevailed in the uninoculated ear and stover during 130-d ensilage. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  3. 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)

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Analyzing the Effect of Variations in Soil and Management Practices on the Sustainability of Corn Stover-Based Bioethanol Production in Mississippi

    Energy Technology Data Exchange (ETDEWEB)

    Woli, Prem [Mississippi State Univ., Mississippi State, MS (United States); Paz, Joel [Mississippi State Univ., Mississippi State, MS (United States)

    2011-08-07

    The inherent variability in corn stover productivity due to variations in soils and crop management practices might contribute to a variation in corn stover-based bioethanol sustainability. This study was carried out to examine how changes in soil types and crop management options would affect corn stover yield (CSY) and the sustainability of the stover-based ethanol production in the Delta region of Mississippi. Based on potential acreage and geographical representation, three locations were selected. Using CERES-Maize model, stover yields were simulated for several scenarios of soils and crop management options. Based on 'net energy value (NEV)' computed from CSYs, a sustainability indicator for stover-based bioethanol production was established. The effects of soils and crop management options on CSY and NEV were determined using ANOVA tests and regression analyses. Both CSY and NEV were significantly different across sandy loam, silt loam, and silty clay loam soils and also across high-, mid-, and low-yielding cultivars. With an increase in irrigation level, both CSY and NEV increased initially and decreased after reaching a peak. A third-degree polynomial relationship was found between planting date and CSY and NEV each. By moving from the lowest to the highest production scenario, values of CSY and NEV could be increased by 86 to 553%, depending on location and weather condition. The effects of variations in soils and crop management options on NEV were the same as on CSY. The NEV was positive for all scenarios, indicating that corn stover-based ethanol production system in the Delta region is sustainable.

  10. 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 crop residue (corn cobs, wheat straw, and corn stover) and chemical treatment (NT or AT) fed at 25% of diet DM. Greater DM (73.7% vs. 66.1%; 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 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.

  11. 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

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

    Science.gov (United States)

    Kaliyan, Nalladurai; Morey, R Vance

    2010-02-01

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

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

    Science.gov (United States)

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

    2016-10-01

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

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

    Science.gov (United States)

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

    2015-02-01

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

  15. Acetic acid-catalyzed hydrothermal pretreatment of corn stover for the production of bioethanol at high-solids content.

    Science.gov (United States)

    Katsimpouras, Constantinos; Christakopoulos, Paul; Topakas, Evangelos

    2016-09-01

    Corn stover (CS) was hydrothermally pretreated using CH3COOH (0.3 %, v/v), and subsequently its ability to be utilized for conversion to ethanol at high-solids content was investigated. Pretreatment conditions were optimized employing a response surface methodology (RSM) with temperature and duration as independent variables. Pretreated CS underwent a liquefaction/saccharification step at a custom designed free-fall mixer at 50 °C for either 12 or 24 h using an enzyme loading of 9 mg/g dry matter (DM) at 24 % (w/w) DM. Simultaneous enzymatic saccharification and fermentation (SSF) of liquefacted corn stover resulted in high ethanol concentration (up to 36.8 g/L), with liquefaction duration having a negligible effect. The threshold of ethanol concentration of 4 % (w/w), which is required to reduce the cost of ethanol distillation, was surpassed by the addition of extra enzymes at the start up of SSF achieving this way ethanol titer of 41.5 g/L.

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

    Science.gov (United States)

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

    2016-04-01

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

  17. Technical Aspects of Acceleration of Enzymatic Conversion of Corn Stover Biomass into Bio-fuels by Low Intensity, Uniform Ultrasound Field

    Science.gov (United States)

    One of the most critical stages of conversion of plant biomass into biofuels employs hydrolysis reactions between highly specific enzymes and matching substrates (e.g. corn stover cellulose with cellulase) that produce soluble sugars, which then could be converted into ethanol. Important benefits of...

  18. 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...

  19. 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.

  20. 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

  1. Oleaginous fungal lipid fermentation on combined acid- and alkali-pretreated corn stover hydrolysate for advanced biofuel production.

    Science.gov (United States)

    Ruan, Zhenhua; Zanotti, Michael; Archer, Steven; Liao, Wei; Liu, Yan

    2014-07-01

    A combined hydrolysis process, which first mixed dilute acid- and alkali-pretreated corn stover at a 1:1 (w/w) ratio, directly followed by enzymatic saccharification without pH adjustment, has been developed in this study in order to minimize the need of neutralization, detoxification, and washing during the process of lignocellulosic biofuel production. The oleaginous fungus Mortierella isabellina was selected and applied to the combined hydrolysate as well as a synthetic medium to compare fungal lipid accumulation and biodiesel production in both shake flask and 7.5L fermentor. Fungal cultivation on combined hydrolysate exhibited comparable cell mass and lipid yield with those from synthetic medium, indicating that the integration of combined hydrolysis with oleaginous fungal lipid fermentation has great potential to improve performance of advanced lignocellulosic biofuel production. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    Liu, Ke; Zhang, Jian; Bao, Jie

    2015-11-01

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

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

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

    DEFF Research Database (Denmark)

    Georgieva, Tania I.; Ahring, Birgitte Kiær

    2007-01-01

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

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

    Science.gov (United States)

    Zhao, Chen; Fang, Hao; Chen, Shaolin

    2017-01-01

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

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

    Science.gov (United States)

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

    1995-09-01

    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

  11. 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.

  12. 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.

  13. 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).

  14. 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.

  15. 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. PMID:27327870

  16. A comparison of dilute aqueous p-toluenesulfonic and sulfuric acid pretreatments and saccharification of corn stover at moderate temperatures and pressures.

    Science.gov (United States)

    Amarasekara, Ananda S; Wiredu, Bernard

    2012-12-01

    Single step pretreatment-saccharification of corn stover was investigated in aqueous p-toluenesulfonic and sulfuric acid media. Dilute aqueous solution of p-toluenesulfonic acid was a better catalyst than aqueous sulfuric acid of the same H(+) ion concentration for single step pretreatment-saccharification of corn stover at moderate temperatures and pressures. For example, 100mg corn stover heated at 150°C for 1h in 0.100 M H(+) aqueous sulfuric acid produced 64 μmol of total reducing sugars (TRS), whereas the sample heated in 0.100 M H(+)p-toluenesulfonic acid produced 165 μmol of TRS under identical conditions. Glucose yield showed a similar trend, as aq. sulfuric acid and p-toluene sulfonic acid media produced 29 and 35 μmol of glucose respectively after 2.5h. Higher catalytic activity of p-toluenesulfonic acid may be due to an interaction with biomass, supported by repulsion of hydrophobic tolyl group by the aqueous phase. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. 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.

  18. Optimization of cellulase mixture for efficient hydrolysis of steam-exploded corn stover by statistically designed experiments.

    Science.gov (United States)

    Zhou, Jin; Wang, Yong-Hong; Chu, Ju; Luo, Ling-Zhi; Zhuang, Ying-Ping; Zhang, Si-Liang

    2009-01-01

    To improve the enzymatic hydrolytic efficiency and reduce production cost, a statistically designed experimental approach was used to optimize the composition of cellulase mixture so as to maximize the amount of glucose produced from steam-exploded corn stover (SECS). Using seven purified enzymes (cellobiohydrolases, Cel7A, Cel6A, Cel6B; endoglucanases, Cel7B, Cel12A, Cel61A; and beta-glucosidase) from Trichoderma viride T 100-14 mutant strain, a multi-enzyme mixture was constituted after screening and optimization. The final optimal composition (mol%) of the multi-enzyme mixture was Cel7A (19.8%), Cel6A (37.5%), Cel6B (4.7%), Cel7B (17.7%), Cel12A (15.2%), Cel61A (2.3%) and beta-glucosidase (2.8%). The subsequent verification experiments followed by glucose assay together with scanning electron microscopy (SEM) observation confirmed the validity of the models. The multi-enzyme mixture displayed a high performance in converting the cellulosic substrate (SECS). The amount of glucose produced (15.5mg/ml) was 2.1 times as that of the crude cellulase preparation. The results indicated that the optimized cellulase mixture is an available and efficient paradigm for the hydrolysis of lignocellulosic substrate. The enhanced cellulolytic activity displayed by the constructed cellulase mixture could be used as an effective tool for producing bioethanol efficiently from cellulose.

  19. 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)

  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. 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.

  2. Impact of pretreatment with dilute sulfuric acid under moderate temperature on hydrolysis of corn stover with two enzyme systems.

    Science.gov (United States)

    Tai, Chao; Keshwani, Deepak

    2014-03-01

    Pretreatment of corn stover with dilute sulfuric acid at moderate temperature was investigated, and glucan digestibility by Cellic CTec2 and Celluclast on the pretreated biomass was compared. Pretreatments were carried out from 60 to 180 min at the temperature from 105 to 135 °C, with acid concentrations ranging from 0.5 to 2% (w/v). Significant portion of xylan was removed during pretreatment, and the glucan digestibility by CTec2 was significantly better than that by Celluclast in all cases. Analysis showed that glucan digestibility by both two enzymes correlated directly with the extent of xylan removal in pretreatment. Confidence interval was built to give a more precise range of glucan conversion and to test the significant difference among pretreatment conditions. Response surface model was built to obtain the optimal pretreatment condition to achieve high glucan conversion after enzymatic hydrolysis. Considering the cost and energy savings, the optimal pretreatment condition of 1.75% acid for 160 min at 135 °C was determined, and glucan conversion can achieve the range from 72.86 to 76.69% at 95% confidence level after enzymatic hydrolysis, making total glucan recovery up to the range from 89.42 to 93.25%.

  3. Comparative techno-economic analysis of steam explosion, dilute sulfuric acid, ammonia fiber explosion and biological pretreatments of corn stover.

    Science.gov (United States)

    Baral, Nawa Raj; Shah, Ajay

    2017-05-01

    Pretreatment is required to destroy recalcitrant structure of lignocelluloses and then transform into fermentable sugars. This study assessed techno-economics of steam explosion, dilute sulfuric acid, ammonia fiber explosion and biological pretreatments, and identified bottlenecks and operational targets for process improvement. Techno-economic models of these pretreatment processes for a cellulosic biorefinery of 113.5 million liters butanol per year excluding fermentation and wastewater treatment sections were developed using a modelling software-SuperPro Designer. Experimental data of the selected pretreatment processes based on corn stover were gathered from recent publications, and used for this analysis. Estimated sugar production costs ($/kg) via steam explosion, dilute sulfuric acid, ammonia fiber explosion and biological methods were 0.43, 0.42, 0.65 and 1.41, respectively. The results suggest steam explosion and sulfuric acid pretreatment methods might be good alternatives at present state of technology and other pretreatment methods require research and development efforts to be competitive with these pretreatment methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Modeling of pretreatment condition of extrusion-pretreated prairie cordgrass and corn stover with poly (oxyethylen)20 sorbitan monolaurate.

    Science.gov (United States)

    Eckard, Anahita Dehkhoda; Muthukumarappan, Kasiviswanathan; Gibbons, William

    2012-05-01

    Extrusion processing has shown potential to be used as a pretreatment method for second-generation bioethanol production. Furthermore, surfactants have been shown to reduce enzyme deactivation and increase the efficiency of hydrolysis. Therefore, a sequential pretreatment technique was developed for corn stover (CS) and prairie cordgrass (PCG) in which a single screw extruder was used for the first pretreatment according to a previously optimized condition using 70-180 °C for feed, barrel, and die zones with 65-155 rpm screw speed. The second pretreatment was optimized in this study at 45-55 °C, 1-4 h, 0.15-0.6 g Tween 20/g glucan according to response surface methodology. Optimization of surfactant pretreatment facilitated the estimation of interaction and higher-order effects for major factors involved in surfactant treatment (temperature, time, surfactant loading). Using 8.6 FPU/g glucan cellulase, the optimum conditions found by fitting appropriate quadratic models to the data increased glucose and xylose yield by 27.5 and 33% for CS and by 21.5 and 27% for PCG, respectively. Tween 20 concentrations and pretreatment temperature were the most significant factors affecting sugar yield (p value <0.05). Studies of SDS concentration at and beyond critical micelle concentration (5.2-100 mM) demonstrated a decrease in sugar yield compared to control.

  5. Method to Produce Durable Pellets at Lower Energy Consumption Using High Moisture Corn Stover and a Corn Starch Binder in a Flat Die Pellet Mill

    Science.gov (United States)

    Tumuluru, Jaya Shankar; Conner, Craig C.; Hoover, Amber N.

    2016-01-01

    A major challenge in the production of pellets is the high cost associated with drying biomass from 30 to 10% (w.b.) moisture content. At Idaho National Laboratory, a high-moisture pelleting process was developed to reduce the drying cost. In this process the biomass pellets are produced at higher feedstock moisture contents than conventional methods, and the high moisture pellets produced are further dried in energy efficient dryers. This process helps to reduce the feedstock moisture content by about 5-10% during pelleting, which is mainly due to frictional heat developed in the die. The objective of this research was to explore how binder addition influences the pellet quality and energy consumption of the high-moisture pelleting process in a flat die pellet mill. In the present study, raw corn stover was pelleted at moistures of 33, 36, and 39% (w.b.) by addition of 0, 2, and 4% pure corn starch. The partially dried pellets produced were further dried in a laboratory oven at 70 °C for 3-4 hr to lower the pellet moisture to less than 9% (w.b.). The high moisture and dried pellets were evaluated for their physical properties, such as bulk density and durability. The results indicated that increasing the binder percentage to 4% improved pellet durability and reduced the specific energy consumption by 20-40% compared to pellets with no binder. At higher binder addition (4%), the reduction in feedstock moisture during pelleting was 510 kg/m3 and >98%, respectively, and the percent fine particles generated was reduced to <3%. PMID:27340875

  6. Method to Produce Durable Pellets at Lower Energy Consumption Using High Moisture Corn Stover and a Corn Starch Binder in a Flat Die Pellet Mill.

    Science.gov (United States)

    Tumuluru, Jaya Shankar; Conner, Craig C; Hoover, Amber N

    2016-06-15

    A major challenge in the production of pellets is the high cost associated with drying biomass from 30 to 10% (w.b.) moisture content. At Idaho National Laboratory, a high-moisture pelleting process was developed to reduce the drying cost. In this process the biomass pellets are produced at higher feedstock moisture contents than conventional methods, and the high moisture pellets produced are further dried in energy efficient dryers. This process helps to reduce the feedstock moisture content by about 5-10% during pelleting, which is mainly due to frictional heat developed in the die. The objective of this research was to explore how binder addition influences the pellet quality and energy consumption of the high-moisture pelleting process in a flat die pellet mill. In the present study, raw corn stover was pelleted at moistures of 33, 36, and 39% (w.b.) by addition of 0, 2, and 4% pure corn starch. The partially dried pellets produced were further dried in a laboratory oven at 70 °C for 3-4 hr to lower the pellet moisture to less than 9% (w.b.). The high moisture and dried pellets were evaluated for their physical properties, such as bulk density and durability. The results indicated that increasing the binder percentage to 4% improved pellet durability and reduced the specific energy consumption by 20-40% compared to pellets with no binder. At higher binder addition (4%), the reduction in feedstock moisture during pelleting was 510 kg/m(3) and >98%, respectively, and the percent fine particles generated was reduced to <3%.

  7. Soil water evaporation and crop residues

    Science.gov (United States)

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

  8. Direct mechanical energy measures of hammer mill comminution of switchgrass, wheat straw, and corn stover and analysis of their particle size distributions

    Energy Technology Data Exchange (ETDEWEB)

    Bitra, V.S.P [University of Tennessee; Womac, A.R. [University of Tennessee; Chevanan, Nehru [University of Tennessee; Miu, P.I. [University of Tennessee; Smith, D.R. [University of Tennessee; Igathinathane, C. [Mississippi State University (MSU); Sokhansanj, Shahabaddine [ORNL

    2009-07-01

    Biomass particle size impacts handling, storage, conversion, and dust control systems. 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 hammer mill. Direct energy inputs were determined for hammer mill operating speeds from 2000 to 3600 rpm for 3.2 mm integral classifying screen and mass input rate of 2.5 kg/min with 90 - and 30 -hammers. Overall accuracy of specific energy measurement was calculated as 0.072 MJ/Mg. Particle size distributions created by hammer mill were determined for mill operating factors using ISO sieve sizes from 4.75 to 0.02 mm in conjunction with Ro-Tap sieve analyzer. A wide range of analytical descriptors were examined to mathematically represent the range of particle sizes in the distributions. Total specific energy (MJ/Mg) was defined as size reduction energy to operate the hammer mill plus that imparted to biomass. Effective specific energy was defined as energy imparted to biomass. Total specific energy for switchgrass, wheat straw, and corn stover grinding increased by 37, 30, and 45% from 114.4, 125.1, and 103.7 MJ/Mg, respectively, with an increase in hammer mill speed from 2000 to 3600 rpm for 90 -hammers. Corresponding total specific energy per unit size reduction was 14.9, 19.7, and 13.5 MJ/Mg mm, respectively. Effective specific energy of 90 -hammers decreased marginally for switchgrass and considerably for wheat straw and it increased for corn stover with an increase in speed from 2000 to 3600 rpm. However, effective specific energy increased with speed to a certain extent and then decreased for 30 -hammers. Rosin Rammler equation fitted the size distribution data with R2 > 0.995. Mass relative span was greater than 1, which indicated a wide distribution of particle sizes. Hammer milling of switchgrass, wheat straw, and corn stover with 3.2 mm screen resulted in well-graded fine-skewed mesokurtic

  9. Adaptation of continuous biogas reactors operating under wet fermentation conditions to dry conditions with corn stover as substrate.

    Science.gov (United States)

    Kakuk, Balázs; Kovács, Kornél L; Szuhaj, Márk; Rákhely, Gábor; Bagi, Zoltán

    2017-08-01

    Corn stover (CS) is the agricultural by-product of maize cultivation. Due to its high abundance and high energy content it is a promising substrate for the bioenergy sector. However, it is currently neglected in industrial scale biogas plants, because of its slow decomposition and hydrophobic character. To assess the maximum biomethane potential of CS, long-term batch fermentations were carried out with various substrate concentrations and particle sizes for 72 days. In separate experiments we adapted the biogas producing microbial community in wet fermentation arrangement first to the lignocellulosic substrate, in Continuous Stirred Tank Reactor (CSTR), then subsequently, by continuously elevating the feed-in concentration, to dry conditions in solid state fermenters (SS-AD). In the batch tests, the produce 90% of the total biomethane yield than the amount of substrate added to the fermentation lowered the specific methane yield. In the CSTR experiment, the daily substrate loading was gradually increased from 1 to 2 g vs /L/day until the system produced signs of overloading. Then the biomass was transferred to SS-AD reactors and the adaptation process was studied. Although the specific methane yields were lower in the SS-AD arrangement (177 mL CH 4 /g vs in CSTR vs. 105 mL in SS-AD), the benefits of process operational parameters, i.e. lower energy consumption, smaller reactor volume, digestate amount generated and simpler configuration, may compensate the somewhat lower yield. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. 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.

  11. 78 FR 33785 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Science.gov (United States)

    2013-06-05

    ... chromatography with Nitrogen-Phosphorus detection (GC-NPD) has been developed and validated for residues of..., crop group 14, hulls at 15 ppm; grain, cereal, crop group 15, except rice grain at 4 ppm; sweet corn..., straw at 15 ppm; corn, field, grain at 0.02 ppm; corn, field, forage at 3 ppm; corn, field, stover at 15...

  12. Corn residue removal and CO2 emissions

    Science.gov (United States)

    Carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4) are the primary greenhouse gases (GHG) emitted from the soil due to agricultural activities. In the short-term, increases in CO2 emissions indicate increased soil microbial activity. Soil micro-organisms decompose crop residues and release...

  13. 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....

  14. Effects of twenty percent alkaline-treated corn stover without or with yucca extract on performance and nutrient mass balance of finishing steers fed modified distillers grains-based diets.

    Science.gov (United States)

    Johnson, J M; Shreck, A L; Nuttelman, B L; Burken, D B; Erickson, G E; Rincker, M J; Cecava, M J; Klopfenstein, T J

    2015-06-01

    Two experiments were conducted with 192 steers each (during the winter [November to May] or summer [June to October]) to evaluate 3 diets with or without Yucca schidigera extract in a 3 × 2 factorial on steer growth performance and N mass balance. One factor was diet (DM basis): 1) 5% untreated corn stover, 51% corn, and 40% modified distillers grains plus solubles (MDGS; CON); 2) 20% calcium oxide-treated corn stover (CaO added at 5% of stover DM), 40% MDGS, and 36% corn (TRT); or 3) 20% untreated corn stover, 40% MDGS, and 36% corn (NONTRT). The other factor was dietary extract at 0 (NOYE) or 1.0 g/d per steer (YE). No interaction between diet and YE was detected (P > 0.51) for growth performance and carcass traits in winter and only for DMI in summer. Final BW, ADG, DMI, or G:F were not different (P ≥ 0.28) between cattle fed CON and TRT, whereas cattle fed NONTRT had lesser ADG, HCW, and G:F compared to CON and TRT in the winter experiment. During the summer, final BW and ADG tended to be greater (P ≥ 0.07) for CON compared to TRT. Cattle fed TRT had reduced (P effect (P > 0.18) on amount (kg/steer) or percentage of N volatized in the winter or summer. All diets had similar amounts (P > 0.13) of DM and OM removed from the pen surface in both summer and winter. Feeding CaO-treated corn stover as a partial grain replacement had no impact on performance in winter but decreased G:F in summer. Although high-fiber diets increased the amount of OM on pen surfaces, they did not impact N volatilized. Feeding a Y. schidigera extract did not affect N balance or manure characteristics.

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

    Science.gov (United States)

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

    2016-12-01

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

  16. Effect of additives on adsorption and desorption behavior of xylanase on acid-insoluble lignin from corn stover and wheat straw.

    Science.gov (United States)

    Li, Yanfei; Ge, Xiaoyan; Sun, Zongping; Zhang, Junhua

    2015-06-01

    The competitive adsorption between cellulases and additives on lignin in the hydrolysis of lignocelluloses has been confirmed, whereas the effect of additives on the interaction between xylanase and lignin is not clear. In this work, the effects of additives, poly(ethylene glycol) 2000, poly(ethylene glycol) 6000, Tween 20, and Tween 80, on the xylanase adsorption/desorption onto/from acid-insoluble lignin from corn stover (CS-lignin) and wheat straw (WS-lignin) were investigated. The results indicated that the additives could adsorb onto isolated lignin and reduce the xylanase adsorption onto lignin. Compared to CS-lignin, more additives could adsorb onto WS-lignin, making less xylanase adsorbed onto WS-lignin. In addition, the additives could enhance desorption of xylanase from lignin, which might be due to the competitive adsorption between xylanase and additives on lignin. The released xylanase from lignin still exhibited hydrolytic capacity in the hydrolysis of isolated xylan and xylan in corn stover. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2016-11-01

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

  18. The effect of metal ions as co-catalysts on acidic ionic liquid catalyzed single-step saccharification of corn stover in water.

    Science.gov (United States)

    Wiredu, Bernard; Amarasekara, Ananda S

    2015-01-01

    The effects of adding Cr(3+), Mn(2+), Fe(3+), Co(2+) Ni(2+), Cu(2+), Zn(2+) and La(3+) chlorides as co-catalysts to 1-(1-propylsulfonic)-3-methylimidazolium chloride acidic ionic liquid catalyzed saccharification of corn stover in aqueous medium was studied at 140-170 °C, by measuring the total reducing sugar (TRS) and glucose yields. The samples with Mn(2+), Fe(3+), Co(2+) as co-catalysts produced higher TRS yields compared to the sample without the metal ions. The Mn(2+) produced the highest catalytic effect enhancements and produced TRS yields of 68.0%, 72.9%, 90.2% and 87.9% at 140, 150, 160 and 170 °C respectively; whereas the corn stover samples without the Mn(2+) produced TRS yields of 42.9%, 52.3%, 54.4% and 53.5% at the same four temperatures. At higher temperatures of 160 and 170 °C, all metal ions studied produced significant enhancements in glucose yields, except Cr(3+). The addition of La(3+) as a co-catalyst produced the highest glucose yield improvement. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Production of a lignocellulolytic enzyme system for simultaneous bio-delignification and saccharification of corn stover employing co-culture of fungi.

    Science.gov (United States)

    Ma, Kedong; Ruan, Zhiyong

    2015-01-01

    Aiming at improving the efficiency of transferring corn stover into sugars, an efficient lignocellulolytic enzyme system was developed and investigated by co-cultivation of the Coprinus comatus with Trichoderma reesei in a single bioreactor. The results showed that the lignocellulolytic enzyme activities of the co-culture exceeded that of the monoculture, suggesting synergistic interaction between two fungi. The highest laccase activity from the co-culture was 2.6-fold increase over that of the C. comatus monoculture and reached a peak 3days earlier. The maximum delignification obtained was 66.5% and about 82% of the original polysaccharides were converted into fermentable sugars by simultaneous bio-delignification and saccharification process. Correlation analysis showed that sugar yields were directly proportional to the lignin degradation. Our results suggested that co-fungi cultivation was a valuable technique for corn stover bioconversion, which could produce high efficiency of lignocellulolytic enzyme system as a cheaper alternative to commercial enzymes for industrial utilization. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Simultaneous saccharification and co-fermentation of aqueous ammonia pretreated corn stover with an engineered Saccharomyces cerevisiae SyBE005.

    Science.gov (United States)

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

    2014-10-01

    Co-fermentation of glucose and xylose from lignocelluloses is an efficient approach to increasing ethanol production. Simultaneous saccharification and co-fermentation (SSCF) of corn stover pretreated with aqueous ammonia was performed using engineered yeast with xylose utilization pathway. Thus far, the effect of the several key factors on SSCF was investigated, including temperature, inoculation size, pre-hydrolysis and pH. Ethanol concentration was achieved to 36.5 g/L during SSCF process with 6% glucan loading. The addition of Tween 20 reduced enzyme loading, i.e., from 15 to 7.5 FPU/gglucan with the same final ethanol concentration. The ethanol concentration was achieved to 70.1g/L at 12% glucan loading. Yeast feeding, combined with substrate and enzyme feeding, was proved to be an efficient approach for SSCF with high solid loading. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. 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.

  2. Hydrolysis of corn-cob lignocellulosic residue from pentose preparation

    Energy Technology Data Exchange (ETDEWEB)

    Primo-Yufera, E.; Gil-Tortosa, C.I.; Garcia-Breijo, F.J. [Universidad Politecnica de Valencia (Spain). Dept. de Ingenieria Quimica y Nuclear

    1995-08-01

    The use of agricultural wastes for energy and intermediary chemicals has economic, ecological and strategic interest. The strong hydrolysis of the lignocellulose residue remaining after mild hydrolysis of pentosans from corn-cobs is described. The process avoids the use of autoclaves by pressing the acidified lignocellulosic mass at a moderate temperature. The effects of different variables on the yields were studied. Under the best conditions tested, 65% of polymeric potential sugars in the residue were recovered as fermentable sugars in the extract. This is the last stage of a complete procedure set up to obtain maximum yields of carbohydrates from agricultural wastes (soluble sugars, pentoses for chemicals, and glucose from cellulose for fermentations). (author)

  3. Effect of mechanical disruption on the effectiveness of three reactors used for dilute acid pretreatment of corn stover Part 1: chemical and physical substrate analysis.

    Science.gov (United States)

    Wang, Wei; Chen, Xiaowen; Donohoe, Bryon S; Ciesielski, Peter N; Katahira, Rui; Kuhn, Erik M; Kafle, Kabindra; Lee, Christopher M; Park, Sunkyu; Kim, Seong H; Tucker, Melvin P; Himmel, Michael E; Johnson, David K

    2014-01-01

    There is considerable interest in the conversion of lignocellulosic biomass to liquid fuels to provide substitutes for fossil fuels. Pretreatments, conducted to reduce biomass recalcitrance, usually remove at least some of the hemicellulose and/or lignin in cell walls. The hypothesis that led to this research was that reactor type could have a profound effect on the properties of pretreated materials and impact subsequent cellulose hydrolysis. Corn stover was dilute-acid pretreated using commercially relevant reactor types (ZipperClave(®) (ZC), Steam Gun (SG) and Horizontal Screw (HS)) under the same nominal conditions. Samples produced in the SG and HS achieved much higher cellulose digestibilities (88% and 95%, respectively), compared to the ZC sample (68%). Characterization, by chemical, physical, spectroscopic and electron microscopy methods, was used to gain an understanding of the effects causing the digestibility differences. Chemical differences were small; however, particle size differences appeared significant. Sum-frequency generation vibrational spectra indicated larger inter-fibrillar spacing or randomization of cellulose microfibrils in the HS sample. Simons' staining indicated increased cellulose accessibility for the SG and HS samples. Electron microscopy showed that the SG and HS samples were more porous and fibrillated because of mechanical grinding and explosive depressurization occurring with these two reactors. These structural changes most likely permitted increased cellulose accessibility to enzymes, enhancing saccharification. Dilute-acid pretreatment of corn stover using three different reactors under the same nominal conditions gave samples with very different digestibilities, although chemical differences in the pretreated substrates were small. The results of the physical and chemical analyses of the samples indicate that the explosive depressurization and mechanical grinding with these reactors increased enzyme accessibility

  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. 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.

  6. 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%.

  7. Effect of mechanical disruption on the effectiveness of three reactors used for dilute acid pretreatment of corn stover Part 1: chemical and physical substrate analysis

    Science.gov (United States)

    2014-01-01

    Background There is considerable interest in the conversion of lignocellulosic biomass to liquid fuels to provide substitutes for fossil fuels. Pretreatments, conducted to reduce biomass recalcitrance, usually remove at least some of the hemicellulose and/or lignin in cell walls. The hypothesis that led to this research was that reactor type could have a profound effect on the properties of pretreated materials and impact subsequent cellulose hydrolysis. Results Corn stover was dilute-acid pretreated using commercially relevant reactor types (ZipperClave® (ZC), Steam Gun (SG) and Horizontal Screw (HS)) under the same nominal conditions. Samples produced in the SG and HS achieved much higher cellulose digestibilities (88% and 95%, respectively), compared to the ZC sample (68%). Characterization, by chemical, physical, spectroscopic and electron microscopy methods, was used to gain an understanding of the effects causing the digestibility differences. Chemical differences were small; however, particle size differences appeared significant. Sum-frequency generation vibrational spectra indicated larger inter-fibrillar spacing or randomization of cellulose microfibrils in the HS sample. Simons’ staining indicated increased cellulose accessibility for the SG and HS samples. Electron microscopy showed that the SG and HS samples were more porous and fibrillated because of mechanical grinding and explosive depressurization occurring with these two reactors. These structural changes most likely permitted increased cellulose accessibility to enzymes, enhancing saccharification. Conclusions Dilute-acid pretreatment of corn stover using three different reactors under the same nominal conditions gave samples with very different digestibilities, although chemical differences in the pretreated substrates were small. The results of the physical and chemical analyses of the samples indicate that the explosive depressurization and mechanical grinding with these reactors increased

  8. 76 FR 69690 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Science.gov (United States)

    2011-11-09

    ... detection of residues by gas chromatography using nitrogen phosphorous detection (GC/NPD). Contact: Andrew..., leafy greens, subgroup 5B at 15 ppm; turnip greens at 15 ppm; corn, sweet, kernel plus cob with husks removed at 0.01 ppm; corn, sweet, forage at 10 ppm; corn, sweet, stover at 30 ppm; vegetable, fruiting...

  9. Agricultural practices and residual corn during spring crane and waterfowl migration in Nebraska

    Science.gov (United States)

    Sherfy, M.H.; Anteau, M.J.; Bishop, A.A.

    2011-01-01

    Nebraska's Central Platte River Valley (CPRV) is a major spring-staging area for migratory birds. Over 6 million ducks, geese, and sandhill cranes (Grus canadensis) stage there en route to tundra, boreal forest, and prairie breeding habitats, storing nutrients for migration and reproduction by consuming primarily corn remaining in fields after harvest (hereafter residual corn). In springs 2005-2007, we measured residual corn density in randomly selected harvested cornfields during early (n=188) and late migration (n=143) periods. We estimated the mean density of residual corn for the CPRV and examined the influence of agricultural practices (post-harvest field management) and migration period on residual corn density. During the early migration period, residual corn density was greater in idle harvested fields than any other treatments of fields (42%, 48%, 53%, and 92% more than grazed, grazed and mulched, mulched, and tilled fields, respectively). Depletion of residual corn from early to late migration did not differ among post-harvest treatments but was greatest during the year when overall corn density was lowest (2006). Geometric mean early-migration residual corn density for the CPRV in 2005-2007 (42.4 kg/ha; 95% CI=35.2-51.5 kg/ha) was markedly lower than previously published estimates, indicating that there has been a decrease in abundance of residual corn available to waterfowl during spring staging. Increases in harvest efficiency have been implicated as a cause for decreasing corn densities since the 1970s. However, our data show that post-harvest management of cornfields also can substantially influence the density of residual corn remaining in fields during spring migration. Thus, managers may be able to influence abundance of high-energy foods for spring-staging migratory birds in the CPRV through programs that influence post-harvest management of cornfields. ?? 2011 The Wildlife Society.

  10. 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.

  11. 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.

  12. Renewable energy from corn residues by thermochemical conversion

    Science.gov (United States)

    Yu, Fei

    Declining fossil oil reserve, skyrocket price, unsecured supplies, and environment pollution are among the many energy problems we are facing today. It is our conviction that renewable energy is a solution to these problems. The long term goal of the proposed research is to develop commercially practical technologies to produce energy from renewable resources. The overall objective of my research is to study and develop thermochemical processes for converting bulky and low-energy-density biomass materials into bio-fuels and value-added bio-products. The rationale for the proposed research is that, once such processes are developed, processing facility can be set up on or near biomass product sites, reducing the costs associated with transport of bulky biomass which is a key technical barrier to biomass conversion. In my preliminary research, several conversion technologies including atmospheric pressure liquefaction, high pressure liquefaction, and microwave pyrolysis have been evaluated. Our data indicated that microwave pyrolysis had the potential to become a simple and economically viable biomass conversion technology. Microwave pyrolysis is an innovative process that provides efficient and uniform heating, and are robust to type, size and uniformity of feedstock and therefore suitable for almost any waste materials without needing to reduce the particle size. The proposed thesis focused on in-depth investigations of microwave pyrolysis of corn residues. My first specific aim was to examine the effects of processing parameters on product yields. The second specific research aim was to characterize the products (gases, bio-oils, and solid residues), which was critical to process optimization and product developments. Other research tasks included conducting kinetic modeling and preliminary mass and energy balance. This study demonstrated that microwave pyrolysis could be optimized to produce high value syngas, liquid fuels and pyrolytic carbons, and had a great

  13. 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.

  14. 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

  15. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, R.G. [Kansas State Univ., Manhattan, KS (United States); Walsh, M.; Graham, R. [Oak Ridge National Laboratory, Oakridge, TN (United States); Sheehan, J.J. [National Renewable Energy Laboratory, Golden, CO (United States)

    2003-07-01

    This paper presents a newly developed methodology to estimate the quantities of crop residues that can be removed while maintaining rain or wind erosion at less than or equal to the tolerable soil-loss level. Several factors directly influence the removal of agricultural residues for bioenergy and bioproduct use such as grain yield, crop rotation, field management practices within a rotation, climate, and physical characteristics of the soil. The authors analyzed six corn and wheat rotations in the 10 largest corn-producing states, Iowa, Illinois, Indiana, Kansas, Minnesota, Missouri, Nebraska, Ohio, South Dakota, and Wisconsin. An evaluation for conventional, mulch-reduced, and no-till field operations was performed of residue removal rates for each rotation. The results showed that potential removable maximum quantities vary from almost 5.5 million dry metric tons per year for a continuous corn rotation using conventional till in Kansas, to in excess of 97 million dry metric tons per year for a corn-wheat rotation using no-till in Illinois. 9 refs., 5 tabs.

  17. 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

  18. Crimped Cover Crop Legume Residue Effects on Sweet Corn (Zea mays L.) Yield in Puerto Rico

    Science.gov (United States)

    Crimped legume residue can control weeds and supply N for sweet corn production if biomass is sufficient. Three sweet corn (Zea mays L.) open pollinated variety “Suresweet 2011” plantings (April, 2013; July 2013; February 2014) were conducted on an Oxisol (very fine, kaolinitic, isohyperthermic and...

  19. 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.

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

    Science.gov (United States)

    Parreiras, Lucas S; Breuer, Rebecca J; Avanasi Narasimhan, Ragothaman; Higbee, Alan J; La Reau, Alex; Tremaine, Mary; Qin, Li; Willis, Laura B; Bice, Benjamin D; Bonfert, Brandi L; Pinhancos, Rebeca C; Balloon, Allison J; Uppugundla, Nirmal; Liu, Tongjun; Li, Chenlin; Tanjore, Deepti; Ong, Irene M; Li, Haibo; Pohlmann, Edward L; Serate, Jose; Withers, Sydnor T; Simmons, Blake A; Hodge, David B; Westphall, Michael S; Coon, Joshua J; Dale, Bruce E; Balan, Venkatesh; Keating, David H; Zhang, Yaoping; Landick, Robert; Gasch, Audrey P; Sato, Trey K

    2014-01-01

    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.

  1. Characterization of Feruloyl Esterases Produced by the Four Lactobacillus Species: L. amylovorus, L. acidophilus, L. farciminis and L. fermentum, Isolated from Ensiled Corn Stover

    Directory of Open Access Journals (Sweden)

    Zhenshang Xu

    2017-06-01

    Full Text Available Lactic acid bacteria (LAB play important roles in silage fermentation, which depends on the production of sufficient organic acids to inhibit the growth of undesirable microorganisms. However, LAB are not able to degrade cellulose and hemicellulose. Bacteria and fibrolytic enzymes are usually used as inoculants to improve the silage quality and digestibility. In the present study, we isolated four Lactobacillus strains (L. amylovorus CGMCC 11056, L. acidophilus CCTCC AB2010208, L. farciminis CCTCC AB2016237 and L. fermentum CCTCC AB2010204 with feruloyl esterase (FAE activities from ensiled corn stover (CS by a plate screening assay. The genes encoding FAEs were cloned and hetero-expressed in Escherichia coli. The optimal temperature and pH of these purified enzymes ranged from 45 to 50°C and from 7.0 to 8.0, respectively. They could hydrolyze hydroxycinnamoyl esters in a substrate-specific manner when methyl ferulate, methyl caffeate, methyl ρ-coumarate and methyl sinapinate were used as substrates. Moreover, these four FAEs were able to hydrolyze CS to release hydroxycinnamic acids. Furthermore, these strains could degrade hydroxycinnamic esters, and L. amylovorus CGMCC 11056 was the most efficient strain among these four isolates. These results provided a new target for the development of inoculants to improve silage quality and digestibility.

  2. 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.

  3. Engineering wild-type robust Pediococcus acidilactici strain for high titer L- and D-lactic acid production from corn stover feedstock.

    Science.gov (United States)

    Yi, Xia; Zhang, Peng; Sun, Jiaoe; Tu, Yi; Gao, Qiuqiang; Zhang, Jian; Bao, Jie

    2016-01-10

    Pediococcus acidilactici TY112 producing L-lactic acid and P. acidilactici ZP26 producing D-lactic acid, were engineered from the wild-type P. acidilactici DQ2 by ldhD or ldh gene disruption, and the robustness of the wild-type strain to the inhibitors derived from lignocellulose pretreatment was maintained well. In simultaneous saccharification and fermentation (SSF), 77.66 g L(-1) of L-lactic acid and 76.76 g L(-1) of D-lactic acid were obtained at 25% (w/w) solids content of dry dilute acid pretreated and biodetoxified corn stover feedstock. L- and D-Lactic acid yield and productivity were highly dependent on the inhibitor removal extent due to the significant down-regulation on the expressions of ldh and ldhD encoding lactate dehydrogenase by inhibitor, especially syringaldehyde and vanillin at the low concentrations. This study provided a prototype of industrial process for high titer L- and D-lactic acid production from lignocellulose feedstock. Copyright © 2015 Elsevier B.V. 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. Characterization of Feruloyl Esterases Produced by the Four Lactobacillus Species: L. amylovorus, L. acidophilus, L. farciminis and L. fermentum, Isolated from Ensiled Corn Stover.

    Science.gov (United States)

    Xu, Zhenshang; He, Huiying; Zhang, Susu; Guo, Tingting; Kong, Jian

    2017-01-01

    Lactic acid bacteria (LAB) play important roles in silage fermentation, which depends on the production of sufficient organic acids to inhibit the growth of undesirable microorganisms. However, LAB are not able to degrade cellulose and hemicellulose. Bacteria and fibrolytic enzymes are usually used as inoculants to improve the silage quality and digestibility. In the present study, we isolated four Lactobacillus strains ( L. amylovorus CGMCC 11056, L. acidophilus CCTCC AB2010208, L. farciminis CCTCC AB2016237 and L. fermentum CCTCC AB2010204) with feruloyl esterase (FAE) activities from ensiled corn stover (CS) by a plate screening assay. The genes encoding FAEs were cloned and hetero-expressed in Escherichia coli . The optimal temperature and pH of these purified enzymes ranged from 45 to 50°C and from 7.0 to 8.0, respectively. They could hydrolyze hydroxycinnamoyl esters in a substrate-specific manner when methyl ferulate, methyl caffeate, methyl ρ-coumarate and methyl sinapinate were used as substrates. Moreover, these four FAEs were able to hydrolyze CS to release hydroxycinnamic acids. Furthermore, these strains could degrade hydroxycinnamic esters, and L. amylovorus CGMCC 11056 was the most efficient strain among these four isolates. These results provided a new target for the development of inoculants to improve silage quality and digestibility.

  6. Engineering and Two-Stage Evolution of a Lignocellulosic Hydrolysate-Tolerant Saccharomyces cerevisiae Strain for Anaerobic Fermentation of Xylose from AFEX Pretreated Corn Stover

    Science.gov (United States)

    Parreiras, Lucas S.; Breuer, Rebecca J.; Avanasi Narasimhan, Ragothaman; Higbee, Alan J.; La Reau, Alex; Tremaine, Mary; Qin, Li; Willis, Laura B.; Bice, Benjamin D.; Bonfert, Brandi L.; Pinhancos, Rebeca C.; Balloon, Allison J.; Uppugundla, Nirmal; Liu, Tongjun; Li, Chenlin; Tanjore, Deepti; Ong, Irene M.; Li, Haibo; Pohlmann, Edward L.; Serate, Jose; Withers, Sydnor T.; Simmons, Blake A.; Hodge, David B.; Westphall, Michael S.; Coon, Joshua J.; Dale, Bruce E.; Balan, Venkatesh; Keating, David H.; Zhang, Yaoping; Landick, Robert; Gasch, Audrey P.; Sato, Trey K.

    2014-01-01

    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. PMID:25222864

  7. 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.

  8. 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.

  9. Transformation kinetics of corn and clover residues in mineral substrates of different composition

    Science.gov (United States)

    Pinskii, D. L.; Maltseva, A. N.; Zolotareva, B. N.; Dmitrieva, E. D.

    2017-06-01

    Mineralization kinetics of corn and clover residues in quartz sand, loam, sand + 15% bentonite, and sand + 30% kaolinite have been studied. A scheme has been proposed for the transformation of plant residues in mineral substrates. Kinetic parameters of mineralization have been calculated with the use of a first-order two-term exponential polynomial. It has been shown that the share of labile organic carbon pool in the clover biomass is higher (57-63%) than in the corn biomass (47-49%), which is related to the biochemical composition of plant residues. The mineralization constants of clover residues generally significantly exceed those of corn because of the stronger stabilization of the decomposition products of corn residues. The turnover time of the labile clover pool (4-9 days) in all substrates and that of the labile corn pool (8-10 days) in sands and substrates containing kaolinites and bentonite are typical for organic acids, amino acids, and simple sugars. In the loamy substrate, the turnover time of labile corn pool is about 46 days due to the stronger stabilization of components of the labile pool containing large amounts of organic acids. The turnover time of the stable clover pool (0.95 years) is significantly lower than that of the stable corn pool (1.60 years) and largely corresponds to the turnover time of plant biomass.

  10. 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...

  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. Utilization of residual nitrogen (15N) from cover crop and urea by corn

    International Nuclear Information System (INIS)

    Silva, Edson Cabral da; Muraoka, Takashi; Trivelin, Paulo Cesar Ocheuze; Buzetti, Salatier; Veloso, Marcos Emanuel da Costa

    2006-01-01

    The majority of N from mineral fertilizers and cover crops is usually not used by the very next corn crop, but can be absorbed by follow-up crops. The objective of this study was to evaluate the use of residual nitrogen from urea, sunnhemp (Crotalaria juncea) and millet (Pennisetum americanum) labeled with 15 N, applied to no-tillage corn in the previous growing season, in a Red Latosol of the Cerrado. The study was conducted in an experimental farm of the Sao Paulo State University (UNESP), Ilha Solteira, in Selviria county (MS), Brazil, in different areas. The experiment had a randomized complete block design, with 15 treatments and four replications. Treatments were applied to corn crop in the 2001/02 and 2003/04 growing seasons. They were distributed in a 3 x 5 factorial layout, representing the combination of three cover crops: sunnhemp, millet and spontaneous vegetation (fallow) and five N rates (as urea): 0, 30, 80, 130, and 180 kg ha-1 of N. After corn harvest, the two areas were followed in the dry season and were followed by corn crop in the 2002/03 (experiment 1) and 2003/04 (experiment 2) growing seasons, using the same fertilizer rate on all plots to distinguish the residual effect of N sources. The average use of residual N from the millet and sunnhemp residues (above-ground part) by corn crop was less than 3.5 and 3 %, respectively, of the initial amount. The corn uptake of residual N from urea increased in a quadratic manner in experiment 1 and linearly in experiment Two as a response to the applied N rates, and the recover was below 3 %. The cover crop type did not affect the use of residual N of urea by corn, and vice-versa. (author)

  13. In situ degradability of corn stover and elephant-grass harvested at four stages of maturity Degradabilidade in situ de híbridos de milho e de capim-elefante colhidos em quatro estádios de maturidade

    Directory of Open Access Journals (Sweden)

    Luis Felipe Prada e Silva

    2008-12-01

    Full Text Available Among tropical forages, corn silage is largely used by farmers trying to explore the maximum genetic potential from the animals. However, other tropical forages, such as elephant-grass (Pennisetum purpureum, are more productive and therefore cheaper to use than corn silage. Our objective was to compare the in situ degradability of elephant-grass with that from corn hybrids, all harvested at four stages of maturity. The experimental design followed a randomized block design with nested subplots. Two corn hybrids: AG5011, ZN8392 were harvested with 25, 30, 35, and 40% dry matter (DM in the whole plant, and separated in stem + leaf sheath + leaf blade (stover, and cobs. Elephant-grass was harvested with 30, 40, 50 and 60 days after a leveling cut. Dried and ground samples were incubated in nylon bags inside the rumen for 0, 6, 12, 24, 48 and 72 h to estimate the kinetics of ruminal DM and neutral detergent fiber (NDF degradation. The advance of maturity increased the NDF and acid detergent fiber (ADF content in elephant-grass, and reduced its DM degradability. However, maturity had little or no effect on fiber content and DM degradability of corn stover. Elephant-grass had a higher NDF degradability than corn stover, and there was no effect of maturity on NDF degradability of either elephant-grass or corn stover. Fiber degradability of elephant-grass was not worse than that of corn stover, and therefore the choice of forage should be made on economical analysis rather than assuming an intrinsic low production potential for elephant-grass based diets.Dentre as forragens, a silagem de milho é amplamente utilizada pelos fazendeiros que visam explorar o máximo do potencial genético dos animais. No entanto, outros volumosos tropicais como o capim-elefante (Pennisetum purpureum são mais produtivos e, portanto, mais baratos do que a silagem de milho. Nosso objetivo foi comparar a degradabilidade in situ do capim-elefante com a degradabilidade de h

  14. 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.

  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. Field Studies to Evaluate Potential Differences between Bt and non-Bt Corn Residue

    Science.gov (United States)

    Some reports suggest that the genetically-modified Bt corn residue may have higher lignin content and that the residue may be more resistant to decomposition. If true, then there are implications for both farming practices, e.g., tillage and planting, as well as global carbon budgets. We conducted ...

  17. Biochemical suitability of crop residues for cellulosic ethanol: disincentives to nitrogen fertilization in corn agriculture.

    Science.gov (United States)

    Gallagher, Morgan E; Hockaday, William C; Masiello, Caroline A; Snapp, Sieglinde; McSwiney, Claire P; Baldock, Jeffrey A

    2011-03-01

    Concerns about energy security and climate change have increased biofuel demand, particularly ethanol produced from cellulosic feedstocks (e.g., food crop residues). A central challenge to cropping for cellulosic ethanol is the potential environmental damage from increased fertilizer use. Previous analyses have assumed that cropping for carbohydrate in residue will require the same amount of fertilizer as cropping for grain. Using (13)C nuclear magnetic resonance, we show that increases in biomass in response to fertilization are not uniform across biochemical classes (carbohydrate, protein, lipid, lignin) or tissues (leaf and stem, grain, reproductive support). Although corn grain responds vigorously and nonlinearly, corn residue shows only modest increases in carbohydrate yields in response to high levels of fertilization (25% increase with 202 kg N ha(-1)). Lignin yields in the residue increased almost twice as much as carbohydrate yields in response to nitrogen, implying that residue feedstock quality declines as more fertilizer is applied. Fertilization also increases the decomposability of corn residue, implying that soil carbon sequestration becomes less efficient with increased fertilizer. Our results suggest that even when corn is grown for grain, benefits of fertilization decline rapidly after the ecosystem's N demands are met. Heavy application of fertilizer yields minimal grain benefits and almost no benefits in residue carbohydrates, while degrading the cellulosic ethanol feedstock quality and soil carbon sequestration capacity.

  18. Bound residues in corn plants treated with 14C-atrazine and bioavailability to rats

    International Nuclear Information System (INIS)

    Khan, S.U.

    1986-01-01

    Corn plants, about 3.5 months old and treated with 14 C-atrazine, were used in an experiment in which the aerial portion of the plants was exhaustively extracted with solvents. The extracted dried material containing bound 14 C-residues was fed to rats. The extracted aerial portion of control corn plants fortified with 14 C-atrazine was also fed to rats. After four days, 88% and 32% of the radioactivity was excreted in the faeces, and 10% and 60% radioactivity was voided in the urine from rats fed plant material containing bound and fortified 14 C-residues, respectively. The data suggest that the bioavailability to rats of bound 14 C-residues in corn material is low. (author)

  19. 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

    /g glucan gave monomeric Glc yields of 83% or 95%, respectively. Yields of Glc and Xyl after pretreatment at a low hydrogen peroxide loading (0.125 g H2O2/g biomass could be improved by extending the pretreatment residence time to 48 h and readjusting the pH to 11.5 every 6 h during the pretreatment. A Glc yield of 77% was obtained using a pretreatment of 15% biomass loading, 0.125 g H2O2/g biomass, and 48 h with pH adjustment, followed by digestion with an optimized commercial enzyme mixture at an enzyme loading of 15 mg protein/g glucan. Conclusions Alkaline peroxide is an effective pretreatment for corn stover. Particular advantages are the use of reagents with low environmental impact and avoidance of special reaction chambers. Reasonable yields of monomeric Glc can be obtained at an H2O2 concentration one-quarter of that used in previous AHP research. Additional improvements in the AHP process, such as peroxide stabilization, peroxide recycling, and improved pH control, could lead to further improvements in AHP pretreatment.

  20. Decomposition of corn and soybean residues under field conditions and their role as inoculum source

    Directory of Open Access Journals (Sweden)

    E.M. Reis

    2011-03-01

    Full Text Available Necrotrophic parasites of above-ground plant parts survive saprophytically, between growing seasons in host crop residues. In an experiment conducted under field conditions, the time required in months for corn and soybean residues to be completely decomposed was quantified. Residues were laid on the soil surface to simulate no-till farming. Crop debris of the two plant species collected on the harvesting day cut into pieces of 5.0cm-long and a 200g mass was added to nylon mesh bags. At monthly intervals, bags were taken to the laboratory for weighing. Corn residues were decomposed within 37.0 months and those of soybean, within 34.5 months. Hw main necrotrophic fungi diagnosed in the corn residues were Colletotrichum gramicola, Diplodia spp. and Gibberella zeae, and those in soybeans residues were Cercospora kikuchii, Colletotrichum spp, Glomerella sp. and Phomopsis spp. Thus, those periods shoulb be observed in crop rotation aimed at to eliminating contaminated residues and, consequently, the inoculum from the cultivated area.

  1. Residual nitrogen fertilization effect of common bean production on succeeding corn intercropped with Congo grass

    Directory of Open Access Journals (Sweden)

    Antonio Carlos de Almeida Carmeis Filho

    Full Text Available ABSTRACT Crop production in conservation systems involving intercropped cultivations mainly with corn have been proposed as a technology to promote sustainability in the Brazilian Cerrado areas. The objective of this work was to evaluate the influence of residual nitrogen fertilization applied in common bean on subsequent corn sole or intercropped with Congo grass (Urochloa ruziziensis in no-tillage system. The experiment was carried out in randomized blocks with three replicates in a split-plot design. The treatments were composed by two cropping systems (sole and intercropped with Congo grass, and the sub-plots were five doses of nitrogen (0; 40; 80; 120 and 160 kg of N ha-1, applied in topdressing on common-bean (previous crop. There was no effect of cropping systems and residual amount of nitrogen application in the vegetative and reproductive development of corn. Corn intercropped with Congo grass leaded an adequate formation of crop residue and total land covering target at sustainability of no-tillage system.

  2. Gasification of agricultural residues in a demonstrative plant: corn cobs.

    Science.gov (United States)

    Biagini, Enrico; Barontini, Federica; Tognotti, Leonardo

    2014-12-01

    Biomass gasification couples the high power efficiency with the possibility of valuably using the byproducts heat and biochar. The use of agricultural wastes instead of woody feedstock extends the seasonal availability of biomasses. The downdraft type is the most used reactor but has narrow ranges of feedstock specifications (above all on moisture and particle size distribution), so tests on a demonstrative scale are conducted to prove the versatility of the gasifier. Measurements on pressure drops, syngas flow rate and composition are studied to assess the feasibility of such operations with corn cobs. Material and energy balances, and performance indexes are compared for the four tests carried out under different biomass loads (66-85 kg/h). A good operability of the plant and interesting results are obtained (gas specific production of 2 m3/kg, gas heating value 5.6-5.8 MJ/m3, cold gas efficiency in the range 66-68%, potential net power efficiency 21.1-21.6%). Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. 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.

  4. Evaluation of residue management practices effects on corn productivity, soil quality, and greenhouse gas emissions

    Science.gov (United States)

    Guzman, Jose German

    The removal of crop residues left after harvest is being considered as a potential feedstock source for bioethanol production which can contribute to the reduction of fossil fuel use and net greenhouse gas (GHG). The objectives of this study were to: (i) examine how tillage, N fertilization rates, residue removal, and their interactions affect crop productivity, (ii) SOC and soil physical properties, and (iii) GHG emissions, and (iv) calculated a soil C budget to determine how much crop residue can be sustainably be removed in Central and Southwest Iowa. After three years of residue removal under different management practices, the findings of this study suggest that a portion of the corn residue that is left on the soil surface after harvest can be removed, with no negative impacts in the short term continuous corn yield in sites at Central and Southwest Iowa. However, significant decreases in SOC sequestration rates, microbial biomass-C, bulk density, soil penetration resistance, wet aggregate stability, and infiltration rates were observed, but varied with soil type and management practices. Additionally, soil surface CO2 and N2O emissions were responsive to management practices; primarily by altering soil temperature, soil water content, soil mineral N, and crop growth. Results from soil C budget show that in 2010 when corn growth was not water stressed (lack of moisture), approximately 35 and 30% of the residue could be sustainably removed in the Central and Southwest sites, respectively. In 2011, drier soil conditions resulted in approximately 2 and 49% of the residue could be sustainably removed in the Central and Southwest sites, respectively.

  5. 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.

  6. Contact and leaf residue activity of insecticides against the sweet Corn pest Euxesta stigmatias (Diptera: Otitidae).

    Science.gov (United States)

    Nuessly, Gregg S; Hentz, Matthew G

    2004-04-01

    Damage by Euxesta stigmatias Loew larvae to sweet corn renders the ears unmarketable. This report evaluates the efficacy of insecticides labeled for armyworm control in Florida sweet corn against E. stigmatias adults. Tests were performed in controlled settings by using direct contact and dried plant residues of esfenvalerate, cyfluthrin, lambda-cyhalothrin, chlorpyrifos, methyl parathion, methomyl, and thiodicarb. Direct application of all insecticides except thiodicarb quickly killed or caused incapacitating sublethal affects (uncoordinated movement, uncontrolled twitching, and hyperextension of mouthparts and ovipositor) to > 75% of the flies. Low rates (0.56 kg [AI]/ha) of chlorpyrifos and methyl parathion provided the most efficient control, killing 100 and 93%, respectively, within 2 h of direct contact. Low rates of pyrethroids induced low mortality but high sublethal effects that together immobilized nearly 100% of adults within 1 h of exposure. Mortality reached 95% within 2 h of direct contact in flies treated with high rates of pyrethroids. Methomyl killed as many as 94%, but required 24 h to reach this level after direct treatment. Residues on dipped leaves and field-treated plants of all tested insecticides except methyl parathion were less effective at killing adults compared with direct contact tests. Pyrethroid residues (particularly cyfluthrin) on field planted sweet corn induced significantly higher levels of sublethal effects (57-70%), and for a longer period of time, compared with materials in the other classes of chemistry.

  7. Dynamics of mycotoxin and Aspergillus flavus levels in aging Bt and non-Bt corn residues under Mississippi no-till conditions.

    Science.gov (United States)

    Abbas, Hamed K; Accinelli, Cesare; Zablotowicz, Robert M; Abel, Craig A; Bruns, H Arnold; Dong, Yanhong; Shier, W Thomas

    2008-08-27

    Mycotoxin and Aspergillus flavus levels in soil-surface corn debris left by no-till agriculture methods (stover, cobs, and cobs with grain) were determined during the December-March fallow period for near-isogenic Bt and non-Bt hybrid corn. By December, average mycotoxin levels in non-Bt corn were many times higher in cobs with grain than in grain harvested in September (total aflatoxins, 774 vs 211 ng/g; total fumonisins, 216 vs 3.5 microg/g; cyclopiazonic acid, 4102 vs 72.2 microg/g; zearalenone, 0.2 vs corn debris fractions decreased during winter but began to rise in March. Levels of all mycotoxins and A. flavus propagules were lower in harvested grain and debris from Bt than non-Bt corn, but differences were significant (p < 0.05) only for aflatoxins.

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

    International Nuclear Information System (INIS)

    Soliman, S.M.

    2006-01-01

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

  9. 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.

  10. Life cycle water consumption and withdrawal requirements of ethanol from corn grain and residues.

    Science.gov (United States)

    Mishra, Gouri Shankar; Yeh, Sonia

    2011-05-15

    We assessed the water requirements of ethanol from corn grain and crop residue. Estimates are explicit in terms of sources-green (GW) and blue (BW) water, consumptive and nonconsumptive requirements across the lifecycle, including evapotranspiration, application and conveyance losses, biorefinery uses, and water use of energy inputs, and displaced requirements or credits due to coproducts. Ethanol consumes 50-146 L/vehicle kilometer traveled (VKT) of BW and 1-60 L/VKT of GW for irrigated corn and 0.6 L/VKT of BW and 70-137 L/VKT of GW for rain-fed corn after coproduct credits. Extending the system boundary to consider application and conveyance losses and the water requirements of embodied energy increases the total BW withdrawal from 23% to 38% and BW + GW consumption from 5% to 16%. We estimate that, in 2009, 15-19% of irrigation water is used to produce the corn required for ethanol in Kansas and Nebraska without coproduct credits and 8-10% after credits. Harvesting and converting the cob to ethanol reduces both the BW and GW intensities by 13%. It is worth noting that the use of GW is not without impacts, and the water quantity and water quality impacts at the local/seasonal scale can be significant for both fossil fuel and biofuel.

  11. Dedicated energy crops and crop residues for bioenergy feedstocks in the Central and Eastern U.S.A.

    Science.gov (United States)

    Dedicated energy crops and crop residues will meet herbaceous feedstock demands for the new bioeconomy in the Central and Eastern USA. Perennial warm-season grasses and corn stover are well-suited to the eastern half of the USA and provide opportunities for expanding agricultural operations in the r...

  12. Physical and sensory properties of corn flakes with added dry residue of wild oregano distillation

    Directory of Open Access Journals (Sweden)

    Košutić Milenko

    2016-01-01

    Full Text Available According to the modern nutritionist opinions, cereal products such as flakes and snacks are the most common foods in the daily diet. Extrusion technology makes it possible to apply different sources of ingredients for the enrichment of cereal-based flakes or snack products. Substances with strong antioxidant properties such as wild oregano have a positive impact on human health. Therefore, they attract the attention of scientists, consumers and food industry experts. This paper investigates the effects of the simultaneous addition of dry residue from wild oregano distillation (0.5 g / 100g of sample and 1 g / 100g of sample, on the physical-textural and color properties of corn flakes in order to create a new product with improved nutritional properties. The addition of dry residue of wild oregano positively influenced physical characteristics (decreased bulk density 30.2 %, increased expansion rate 44.9 %, as well as texture hardness and the work of compression, 38.1 % and 40.3 %, respectively. Also, oregano significantly changed the color of flakes. Tukey’s HSD test showed statistically significant differences between most of the mean values of physical-textural, color and sensory attributes in the oregano-added corn flakes compared to the control sample. Principal component analysis has been applied to classify the samples according to differences in the studied parameters. The data pointed out that investigated corn flakes with the addition of wild oregano are new food products with good physical-textural and sensory properties due to a higher level of antioxidant activity. Moreover, it may contribute to the valorization of edible industrial waste in food production. [Projekat Ministarstva nauke Republike Srbije, br. III 46005 i br. TR 31027

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

    African Journals Online (AJOL)

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

  14. Role of mineral matrix composition and properties in the transformation of corn residues

    Directory of Open Access Journals (Sweden)

    David Pinskiy

    2014-08-01

    Full Text Available The influence of the composition and properties of the mineral matrix in soils on the humification of corn residues was studied. The substrate (silica sand, loam, silica sand + 10% bentonite, or silica sand + 30% kaolinite was mixed with 10% corn residues (milled to 3–5 mm and incubated under stationary conditions for 6–19 months. Sampling for the analysis was performed every month, and a few times in the first month. The dynamics of mineralization and humification of plant residues was studied by applying elemental and bulk analyses of neogenic organic matter (OM, densitometric fractionation of substrates, FTIR spectroscopy, solid-phase 13C-NMR spectroscopy, and scanning electron microscopy with an electron microprobe. It was shown that the humification processes had a wavelike character for loam and sand substrates, which could be explained by the transformation of the microorganism populations together with the change in the amount and quality of OM in the system. The main mechanism for the stabilization of neogenic OM was adsorption on a mineral matrix with formation of relatively resistant compounds. This adsorption can be selective, depending on the composition and properties of the mineral matrix. The FTIR and 13C-NMR analyses of OM distribution in different substrates and densitometric fractions showed that sand and heavy fractions (HF >2.2 g/cm3 were enriched with compounds of an aromatic nature and polypeptides. Light fractions (LF-2, 1.4–2.2 g/cm3 accumulated compounds that also contained alkyl and carboxyl groups. The sandy substrate and HF have higher aromaticity indices than LF-2. Higher aromaticity index values of humus substances in the sandy substrate and HF in the loamy substrate, compared to LF-2, evidenced the formation of steady aromatic compounds, in which there may be kernels of humic acids (HA. We do not exclude the possibility of the matrix synthesis of the HA-like substances.

  15. A comparison of corn (Zea mays L.) residue and its biochar on soil C and plant growth.

    Science.gov (United States)

    Calderón, Francisco J; Benjamin, Joseph; Vigil, Merle F

    2015-01-01

    In order to properly determine the value of charring crop residues, the C use efficiency and effects on crop performance of biochar needs to be compared to the un-charred crop residues. In this study we compared the addition of corn stalks to soil, with equivalent additions of charred (300 °C and 500 °C) corn residues. Two experiments were conducted: a long term laboratory mineralization, and a growth chamber trial with proso millet plants. In the laboratory, we measured soil mineral N dynamics, C use efficiency, and soil organic matter (SOM) chemical changes via infrared spectroscopy. The 300 °C biochar decreased plant biomass relative to a nothing added control. The 500°C biochar had little to no effect on plant biomass. With incubation we measured lower soil NO3 content in the corn stalk treatment than in the biochar-amended soils, suggesting that the millet growth reduction in the stalk treatment was mainly driven by N limitation, whereas other factors contributed to the biomass yield reductions in the biochar treatments. Corn stalks had a C sequestration use efficiency of up to 0.26, but charring enhanced C sequestration to values that ranged from 0.64 to 1.0. Infrared spectroscopy of the soils as they mineralized showed that absorbance at 3400, 2925-2850, 1737 cm-1, and 1656 cm-1 decreased during the incubation and can be regarded as labile SOM, corn residue, or biochar bands. Absorbances near 1600, 1500-1420, and 1345 cm-1 represented the more refractory SOM moieties. Our results show that adding crop residue biochar to soil is a sound C sequestration technology compared to letting the crop residues decompose in the field. This is because the resistance to decomposition of the chars after soil amendment offsets any C losses during charring of the crop residues.

  16. Residual and cumulative effects of soil application of sewage sludge on corn productivity.

    Science.gov (United States)

    Vieira, Rosana Faria; Moriconi, Waldemore; Pazianotto, Ricardo Antônio Almeida

    2014-05-01

    The objective of this study was to evaluate the effect of frequent and periodic applications of sewage sludge to the soil, on corn productivity. The experiment was carried out as part of an experiment that has been underway since 1999, using two types of sludge. One came from the Barueri Sewage Treatment Station (BS, which receives both household and industrial sludge) and the other came from the Franca Sewage Treatment Station (FS, which receives only household sludge). The Barueri sludge was applied from 1999 up to the agricultural year of 2003/2004. With the exception of the agricultural years of 2004/2005 and 2005/2006, the Franca sludge was applied up to 2008/2009. All the applications were made in November, with the exception of the first one which was made in April 1999. After harvesting the corn, the soil remained fallow until the next cultivation. The experiment was set up as a completely randomized block design with three replications and the following treatments: control without chemical fertilization or sludge application, mineral fertilization, and dose 1 and dose 2 of sludge (Franca and Barueri). The sludges were applied individually. Dose 1 was calculated by considering the recommended N application for corn. Dose 2 was twice dose 1. It was evident from this work that the successive application of sludge to the soil in doses sufficient to reach the productivity desired with the use of nitrogen fertilizers could cause environmental problems due to N losses to the environment and that the residual and cumulative effects should be considered when calculating the application of sludge to soil.

  17. Simultaneous saccharification and cofermentation of lignocellulosic residues from commercial furfural production and corn kernels using different nutrient media

    Directory of Open Access Journals (Sweden)

    Cristhian Carrasco

    2011-07-01

    Full Text Available Abstract Background As the supply of starch grain and sugar cane, currently the main feedstocks for bioethanol production, become limited, lignocelluloses will be sought as alternative materials for bioethanol production. Production of cellulosic ethanol is still cost-inefficient because of the low final ethanol concentration and the addition of nutrients. We report the use of simultaneous saccharification and cofermentation (SSCF of lignocellulosic residues from commercial furfural production (furfural residue, FR and corn kernels to compare different nutritional media. The final ethanol concentration, yield, number of live yeast cells, and yeast-cell death ratio were investigated to evaluate the effectiveness of integrating cellulosic and starch ethanol. Results Both the ethanol yield and number of live yeast cells increased with increasing corn-kernel concentration, whereas the yeast-cell death ratio decreased in SSCF of FR and corn kernels. An ethanol concentration of 73.1 g/L at 120 h, which corresponded to a 101.1% ethanol yield based on FR cellulose and corn starch, was obtained in SSCF of 7.5% FR and 14.5% corn kernels with mineral-salt medium. SSCF could simultaneously convert cellulose into ethanol from both corn kernels and FR, and SSCF ethanol yield was similar between the organic and mineral-salt media. Conclusions Starch ethanol promotes cellulosic ethanol by providing important nutrients for fermentative organisms, and in turn cellulosic ethanol promotes starch ethanol by providing cellulosic enzymes that convert the cellulosic polysaccharides in starch materials into additional ethanol. It is feasible to produce ethanol in SSCF of FR and corn kernels with mineral-salt medium. It would be cost-efficient to produce ethanol in SSCF of high concentrations of water-insoluble solids of lignocellulosic materials and corn kernels. Compared with prehydrolysis and fed-batch strategy using lignocellulosic materials, addition of starch

  18. Cover crop management influences residue biomass and subsequent weed suppression in a conservation agriculture corn and cotton rotation

    Science.gov (United States)

    Use of winter cover crops is an integral component of conservation systems in corn and cotton. However, data concerning cover management and subsequent residue and weed biomass is needed. Field experiments were conducted from autumn of 2003 through cash crop harvest in 2006 at the Alabama Agricultur...

  19. Tillage and residue effects on rainfed wheat and corn production in the Semi-Arid Regions of Northern China

    NARCIS (Netherlands)

    Wang, X.B.; Hoogmoed, W.B.; Perdok, U.D.; Cai, D.X.

    2003-01-01

    Field studies on tillage and residue management for spring corn were conducted at two sites, in Tunliu (1987-1990), and Shouyang (1992-1995) counties of Shanxi province in the semihumid arid regions of northern China. This paper discusses the effects of different fall tillage (winter fallow tillage)

  20. Nitrogen fertilization (15NH4NO3 of palisadegrass and residual effect on subsequent no-tillage corn

    Directory of Open Access Journals (Sweden)

    Emerson Borghi

    2014-10-01

    Full Text Available Nitrogen is required in large amounts by plants and their dinamics in corn and perennial forages intercropped is little known. This study analyzed the efficiency of nitrogen fertilization (15NH4NO3 applied after corn grain harvest to palisadegrass (Brachiaria brizantha cv. Marandu in intercrops sown at two times, as well as the N residual effect on the subsequent corn crop. The field experiment was performed in Botucatu, São Paulo State, in southeastern Brazil, on a structured Alfisol under no-tillage. The experiment was arranged in a randomized block design in a split plot scheme with four replications. The main plots consisted of two intercropping systems (corn and palisadegrass sown together and palisadegrass sown later, at corn top-dressing fertilization. The subplots consisted of four N rates (0, 30, 60, and 120 kg ha-1 N. The subplots contained microplots, in which enriched ammonium nitrate (15NH4NO3 was applied at the same rates. The time of intercrop sowing affected forage dry matter production, the amount of fertilizer-derived N in and the N use efficiency by the forage plants. Nitrogen applied in autumn to palisadegrass intercropped with corn, planted either at corn sowing or at N top-dressing fertilization, increased the forage yield up to a rate of 60 kg ha-1. The amount of fertilizer-derived N by the forage plants and the fertilizer use efficiency by palisadegrass were highest 160 days after fertilization for both intercrop sowing times, regardless of N rates. Residual N did not affect the N nutrition of corn plants grown in succession to palisadegrass, but increased grain yield at rates of 60 and 120 kg ha-1 N, when corn was grown on palisadegrass straw from the intercrop installed at corn fertilization (top-dressing. Our results indicated that the earlier intercropping allowed higher forage dry matter production. On the other hand, the later intercrop allowed a higher corn grain yield in succession to N-fertilized palisadegrass.

  1. Effect of Tillage Systems with Corn Residue on Grain Yield of Rapeseed in Moghan Region

    Directory of Open Access Journals (Sweden)

    J Taghinazhad

    2014-09-01

    Full Text Available This study carried out to evaluate the effect of different tillage systems on rapeseed yield (hayola 401 planted in corn residues. This experiment was done in Moghan region with clay soils during 2009-2012. Different seedbed preparation methods include MT: moldboard + disk tillage (conventional tillage was included, SCT: Stem Crusher + chisel + disk tandem harrow, STT: Stem Crusher + double-disc, CT: chisel + disk tillage and DD: two heavy disks. The experiment was conducted in a randomized complete block design with four replications. The results showed that soil bulk density in the 0-10 cm layer was not significant in different tillage treatments, but it was significantly higher than the conventional tillage in 10-20 cm depth. However, penetration resistance in 10-30 cm under DD was significantly higher than other treatments, but it was not significant in 0-10 cm layer among all tillage treatments. Thus, Comparison of the soil bulk density, penetration resistance, and plant establishment showed that the reduced tillage in canola seedbed preparation was effective. Besides, the surveys indicated that there was a significant different between MWD after primary and secondary tillage. The mean diameter weighted under SCT and DD, were 1.19 and 1.24 cm, respectively had the best status. The highest value and the worst status of this parameter observed for MT which was 1.92 cm. The highest rate of grain yield obtained by application of treatment SCT, and it was 2563.8 kg ha-1, The SCT treatment can be recommended as an effective canola bed preparation due to its significant saving in time and cost after corn harvesting.

  2. Corn-based feedstock for biofuels: Implications for agricultural sustainability

    Science.gov (United States)

    Tan, Z.

    2010-12-01

    Crop residue as a source of feedstock for biofuels production must retain ecosystem services and be sustainable. The challenge is to develop cropping system management strategies that balance the demand for increasing biofuel needs with ecosystem sustainability. This study was designed to evaluate impacts of changes in land use and management caused by corn-based biofuel production (grain, cob, stover) on soil fertility and ecosystem sustainability. Our specific goal was to investigate how the levels of corn residue removal influence current soil carbon and nutrient budgets and how these budgets are maintained under proposed production scenarios. Soil organic carbon (SOC), an important carbon component in the life cycle of biofuel production, is a sensitive indicator of cropping system sustainability. We used a soil carbon and nutrient balance approach developed from published field observations and a validated mechanistic model to analyze historical corn grain yields and fertilizer usage associated with various management practices at the county scale across the United States. Our analyses show that ecosystem carbon flux demonstrates significant spatial variability, relying heavily on the total biomass production level and residue harvest intensity; SOC budgets depend mainly on the proportion of residue removal, tillage type, and previous SOC stock level. Our results also indicate that corn cob removal for biofuel has little effect on soil carbon and nutrient balances under conventional management practices, while necessary irrigation can contribute greatly to corn-based biofuel production and ecosystem sustainability in the western side of the Great Plains and the eastern foothills of the Rocky Mountains.

  3. Energy balance of a corn residue-covered field during snowmelt

    International Nuclear Information System (INIS)

    Sauer, T.J.; Hatfield, J.L.; Prueger, J.H.; Logsdon, S.D.

    1998-01-01

    Transport of agricultural chemicals in runoff and recharge waters from snowmelt and soil thawing may represent a significant event in terms of annual contaminant loadings in temperate regions. Improved understanding of the melt dynamics of shallow snowpacks is necessary to fully assess the implications for water quality. The objective of this study was to measure the energy balance components of a corn (Zea mays L.) stubble field during the melting of its snowcover. Net radiation (Rn), soil (G), sensible (H), and latent (Q) best fluxes were measured in a field near Ames, Iowa, during the winter of 1994-1995. Energy consumed by melting including change in energy storage of the snowpack was determined as the residual of the measured energy balance. There was continuous snowcover at the field site for 71 days (maximum depth = 222 m) followed by an open period of 11 days before additional snowfall and a second melt period. The net radiation and snowmelt/energy storage change (S) terms dominated the energy balance during both measurement intervals. Peak daily sensible and latent best fluxes were below 100 W m(-2) on all days except the last day of the second melt period. There was good agreement between predicted and measured values of H and Q during the melting of an aged snow layer but poorer agreement during the melt of fresh snow. Both snowpacks melted rapidly and coincident changes in soil moisture storage were observed. Improved estimates of Q and H, especially for partially open surfaces, will require better characterization of the surface aerodynamic properties and spatially-representative surface temperature measurements

  4. Comparative study of sulfite pretreatments for robust enzymatic saccharification of corn cob residue

    Directory of Open Access Journals (Sweden)

    Bu Lingxi

    2012-12-01

    Full Text Available Abstract Background Corn cob residue (CCR is a kind of waste lignocellulosic material with enormous potential for bioethanol production. The moderated sulphite processes were used to enhance the hydrophily of the material by sulfonation and hydrolysis. The composition, FT-IR spectra, and conductometric titrations of the pretreated materials were measured to characterize variations of the CCR in different sulfite pretreated environments. And the objective of this study is to compare the saccharification rate and yield of the samples caused by these variations. Results It was found that the lignin in the CCR (43.2% had reduced to 37.8%, 38.0%, 35.9%, and 35.5% after the sulfite pretreatment in neutral, acidic, alkaline, and ethanol environments, respectively. The sulfite pretreatments enhanced the glucose yield of the CCR. Moreover, the ethanol sulfite sample had the highest glucose yield (81.2%, based on the cellulose in the treated sample among the saccharification samples, which was over 10% higher than that of the raw material (70.6%. More sulfonic groups and weak acid groups were produced during the sulfite pretreatments. Meanwhile, the ethanol sulfite treated sample had the highest sulfonic group (0.103 mmol/g and weak acid groups (1.85 mmol/g in all sulfite treated samples. In FT-IR spectra, the variation of bands at 1168 and 1190 cm-1 confirmed lignin sulfonation during sulfite pretreatment. The disappearance of the band at 1458 cm-1 implied the methoxyl on lignin had been removed during the sulfite pretreatments. Conclusions It can be concluded that the lignin in the CCR can be degraded and sulfonated during the sulfite pretreatments. The pretreatments improve the hydrophility of the samples because of the increase in sulfonic group and weak acid groups, which enhances the glucose yield of the material. The ethanol sulfite pretreatment is the best method for lignin removal and with the highest glucose yield.

  5. Efeito residual do lodo de esgoto na produtividade do milho safrinha Residual effect of sewage sludge on off-season corn yield

    Directory of Open Access Journals (Sweden)

    Graziela Moraes de Cesare Barbosa

    2007-06-01

    Full Text Available Das opções de disposição final do lodo de esgoto, a reciclagem agrícola tem sido uma das mais utilizadas em diversos países desenvolvidos, sendo considerada a forma mais adequada em termos técnicos, econômicos e ambientais. Este trabalho teve por objetivo avaliar o efeito residual do lodo de esgoto na produtividade do milho safrinha, após dois anos de aplicação consecutiva desse resíduo em um Latossolo Vermelho eutroférrico. O experimento foi realizado em campo, em delineamento em blocos ao acaso com três repetições, e os tratamentos foram os seguintes: testemunha e adubações com lodo de esgoto nas doses de 6, 12, 24 e 36 t ha-1 (peso de matéria seca. Houve efeito residual do uso do lodo de esgoto caleado na produtividade de milho safrinha; a dose de 36 t ha-1 foi estatisticamente superior às doses de 6 e 12 t ha-1.Among the possibilities of final disposal of sewage sludge, agricultural recycling has become one of the most widely used in several developed countries, and is considered the most appropriate in technical, economical and environmental terms. This study aimed at evaluating the sewage sludge residual effect on off-season corn yield on an Eutroferric Red Latossol (Oxisol. The field experiment was in a randomized block design with three replications, with treatments consisting of increasing doses of sewage sludge (0, 6, 12, 24 and 36 t ha-1, on a dry weight basis, applied in the two previous cropping seasons.. The residual effect of the application of lime-stabilized sewage sludge increased the yield of off-season corn; the grain yield under a rate of 36 t ha-1 was statistically higher than those under 6 and 12 t ha-1.

  6. 40 CFR 180.544 - Methoxyfenozide; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ..., grain 0.05 Corn, field, refined oil 0.20 Corn, field, stover 125 Corn, pop, grain 0.05 Corn, pop, stover... 9 0.3 Vegetable, foliage of legume, except soybean, subgroup 7A 35 Vegetable, fruiting, group 8 2.0 Vegetable, leaves of root and tuber, group 2 30 Vegetable, legume, edible podded, subgroup 6A 1.5 Vegetable...

  7. 78 FR 63938 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Science.gov (United States)

    2013-10-25

    ... conducted by gas chromatograph equipped with nitrogen phosphorus detector (GC-NPD), electron capture...], including its metabolites and degradates, in or on corn, field, forage from 0.75 ppm to 5.0 ppm; corn, field, stover from 1.5 ppm to 15 ppm; corn, pop, stover from 1.5 ppm to 15 ppm; and cattle, meat byproducts at 0...

  8. 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...

  9. Agro-industrial residue from starch extraction of Pachyrhizus ahipa as filler of thermoplastic corn starch films.

    Science.gov (United States)

    López, O V; Versino, F; Villar, M A; García, M A

    2015-12-10

    Biocomposites films based on thermoplastic corn starch (TPS) containing 0.5% w/w fibrous residue from Pachyrhizus ahipa starch extraction (PASR) were obtained by melt-mixing and compression molding. PASR is mainly constituted by remaining cell walls and natural fibers, revealed by Scanning Electron Microscopy (SEM). Chemical composition of the residue indicated that fiber and starch were the principal components. Biocomposites thermo-stability was determined by Thermo-Gravimetric Analysis. A continuous PASR-TPS interface was observed by SEM, as a result of a good adhesion of the fibrous residue to starch matrix. Likewise, films containing PASR presented fewer superficial cracks than TPS ones, whereas their fracture surfaces were more irregular. Besides, the presence of PASR increased starch films roughness, due to fibers agglomerates. Films reinforced with PASR showed significantly lower water vapor permeability (WVP). In addition, PARS filler increased maximum tensile strength and Young's modulus of TPS films, thus leading to more resistant starch matrixes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. 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)

  11. Evaluating residues from batai trees (Paraserianthes falcataria) as alternative sources of nitrogen for grain corn (zeas mays l.) in the humid tropics

    International Nuclear Information System (INIS)

    Zaharah, A.R.; Chintu, R.; Ghizan, S.

    2002-01-01

    The use of chemical fertilizers for mitigating N deficiency is unsustainable in many tropical areas because of economic constraints and possible deleterious effects on environmental quality. Although organic inputs such as green manures and litter from legumes have shown some potential for improving soil N status, the synchrony of N release from these residues with crop demand needs to be seriously addressed. The potential of above- and below-ground residues of Batai (Paraserianthes falcataria) to improve soil N availability and uptake by corn in an Ultisol (Bungor series) was evaluated under field and controlled conditions. The effect of residue quality on the kinetics of N release and accumulation in the soil was studied in field and laboratory incubation studies, whilst N uptake by grain corn was quantified using direct and indirect 1 5 N isotope labeling techniques. Treatments consist of fresh leaves, roots and 1:1 mixture of roots and leaves of Batai. Residue quality in terms of lignin + polyphenol-to-N ratio, and N mineralization was in the order roots 3 -N leaching occurred between 30 and 60 days after treatment (DAT). Significant amounts of Ca, Mg and K were also leached beyond 20 cm after 60 days. Both 15 N-labeling methods showed that N recovery in corn was much higher in the root than the leaf treatments. However, integrating Batai residues with an inorganic N source could be a more effective management strategy for improving N use efficiency and mitigating soil acidity. (Author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1979-07-31

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

  13. Stover harvest impacts soil and hydrologic properties on three Minnesota farms

    Science.gov (United States)

    Stover is the material remaining after harvesting corn (Zea Mays L.) grain, which may be removed for a variety of purposes, but these material are also crucial for protecting and enriching soil properties. This research was conducted on-farm in collaboration to assess the impact of harvesting cobs (...

  14. Nutrient digestion and performance by lambs and steers fed thermochemically treated crop residues.

    Science.gov (United States)

    Sewell, J R; Berger, L L; Nash, T G; Cecava, M J; Doane, P H; Dunn, J L; Dyer, M K; Pyatt, N A

    2009-03-01

    Five studies were conducted to determine nutrient digestibility and performance of lambs and steers fed thermochemically treated crop residues and distillers dried grains with solubles (DDGS) as a corn replacement pellet (CRP; 75% residue:25% DDGS, DM basis). Fifteen Hampshire, Suffolk, or Dorset wethers (BW 33.3 +/- 5.0 kg) were utilized to evaluate nutrient digestibility of the unprocessed native (NAT) and CRP [Exp. 1: wheat straw (WS); Exp. 2: corn stover (CS); Exp. 3: switchgrass (SWG) and corn fiber:wheat chaff (CFWC)] when limit fed (Exp. 1 and 2: 1.8% of BW daily; Exp. 3: 2.5% of BW daily) compared with a 60% corn diet. In Exp. 4, 56 individually fed Dorset-cross wether lambs (BW 32.0 +/- 1.4 kg) were utilized to compare performance and digestibility of WS, wheat chaff (WC), corn fiber (CF), a 3:1 blend of corn fiber:wheat straw (CFWS), a 3:1 blend of CFWC, and SWG-CRP fed for ad libitum intake compared with a 45% corn diet. In Exp. 5, 32 individually fed Holstein steers (BW 185.2 +/- 0.9 kg) were used to evaluate performance and digestibility of diets containing corn, WS-CRP, CFWC-CRP, or NAT-WS fed for ad libitum intake. Crop residues were processed with 5% calcium oxide (DM basis) and 35% water in a double-shaft enclosed mixer (Readco Kurimoto Continuous Processor, York, PA) and subsequently pelleted with DDGS to form CRP. Feeding lambs WS-CRP (Exp. 1) or CS-CRP (Exp. 2) increased digestion of DM, NDF, and ADF compared with NAT (P crop residues are thermochemically processed. Processed crop residues may be fed in combination with DDGS to partially replace corn in ruminant diets.

  15. Decomposition rates and residue-colonizing microbial communities of Bacillus thuringiensis insecticidal protein Cry3Bb-expressing (Bt) and non-Bt corn hybrids in the field.

    Science.gov (United States)

    Xue, Kai; Serohijos, Raquel C; Devare, Medha; Thies, Janice E

    2011-02-01

    Despite the rapid adoption of crops expressing the insecticidal Cry protein(s) from Bacillus thuringiensis (Bt), public concern continues to mount over the potential environmental impacts. Reduced residue decomposition rates and increased tissue lignin concentrations reported for some Bt corn hybrids have been highlighted recently as they may influence soil carbon dynamics. We assessed the effects of MON863 Bt corn, producing the Cry3Bb protein against the corn rootworm complex, on these aspects and associated decomposer communities by terminal restriction fragment length polymorphism (T-RFLP) analysis. Litterbags containing cobs, roots, or stalks plus leaves from Bt and unmodified corn with (non-Bt+I) or without (non-Bt) insecticide applied were placed on the soil surface and at a 10-cm depth in field plots planted with these crop treatments. The litterbags were recovered and analyzed after 3.5, 15.5, and 25 months. No significant effect of treatment (Bt, non-Bt, and non-Bt+I) was observed on initial tissue lignin concentrations, litter decomposition rate, or bacterial decomposer communities. The effect of treatment on fungal decomposer communities was minor, with only 1 of 16 comparisons yielding separation by treatment. Environmental factors (litterbag recovery year, litterbag placement, and plot history) led to significant differences for most measured variables. Combined, these results indicate that the differences detected were driven primarily by environmental factors rather than by any differences between the corn hybrids or the use of tefluthrin. We conclude that the Cry3Bb corn tested in this study is unlikely to affect carbon residence time or turnover in soils receiving these crop residues.

  16. Neonicotinoid insecticide residues in surface water and soil associated with commercial maize (corn) fields in southwestern Ontario.

    Science.gov (United States)

    Schaafsma, Arthur; Limay-Rios, Victor; Baute, Tracey; Smith, Jocelyn; Xue, Yingen

    2015-01-01

    Neonicotinoid insecticides have come under scrutiny for their potential unintended effects on non-target organisms, particularly pollinators in agro-ecosystems. As part of a larger study of neonicotinoid residues associated with maize (corn) production, 76 water samples within or around the perimeter of 18 commercial maize fields and neighbouring apiaries were collected in 5 maize-producing counties of southwestern Ontario. Residues of clothianidin (mean = 2.28, max. = 43.60 ng/mL) and thiamethoxam (mean = 1.12, max. = 16.50 ng/mL) were detected in 100 and 98.7% of the water samples tested, respectively. The concentration of total neonicotinoid residues in water within maize fields increased six-fold during the first five weeks after planting, and returned to pre-plant levels seven weeks after planting. However, concentrations in water sampled from outside the fields were similar throughout the sampling period. Soil samples from the top 5 cm of the soil profile were also collected in these fields before and immediately following planting. The mean total neonicotinoid residue was 4.02 (range 0.07 to 20.30) ng/g, for samples taken before planting, and 9.94 (range 0.53 to 38.98) ng/g, for those taken immediately after planting. Two soil samples collected from within an conservation area contained detectable (0.03 and 0.11 ng/g) concentrations of clothianidin. Of three drifted snow samples taken, the drift stratum containing the most wind-scoured soil had 0.16 and 0.20 ng/mL mainly clothianidin in the melted snow. The concentration was at the limit of detection (0.02 ng/mL) taken across the entire vertical profile. With the exception of one sample, water samples tested had concentrations below those reported to have acute, chronic or sublethal effects to honey bees. Our results suggest that neonicotinoids may move off-target by wind erosion of contaminated soil. These results are informative to risk assessment models for other non-target species in maize agro-ecosytems.

  17. Neonicotinoid insecticide residues in surface water and soil associated with commercial maize (corn fields in southwestern Ontario.

    Directory of Open Access Journals (Sweden)

    Arthur Schaafsma

    Full Text Available Neonicotinoid insecticides have come under scrutiny for their potential unintended effects on non-target organisms, particularly pollinators in agro-ecosystems. As part of a larger study of neonicotinoid residues associated with maize (corn production, 76 water samples within or around the perimeter of 18 commercial maize fields and neighbouring apiaries were collected in 5 maize-producing counties of southwestern Ontario. Residues of clothianidin (mean = 2.28, max. = 43.60 ng/mL and thiamethoxam (mean = 1.12, max. = 16.50 ng/mL were detected in 100 and 98.7% of the water samples tested, respectively. The concentration of total neonicotinoid residues in water within maize fields increased six-fold during the first five weeks after planting, and returned to pre-plant levels seven weeks after planting. However, concentrations in water sampled from outside the fields were similar throughout the sampling period. Soil samples from the top 5 cm of the soil profile were also collected in these fields before and immediately following planting. The mean total neonicotinoid residue was 4.02 (range 0.07 to 20.30 ng/g, for samples taken before planting, and 9.94 (range 0.53 to 38.98 ng/g, for those taken immediately after planting. Two soil samples collected from within an conservation area contained detectable (0.03 and 0.11 ng/g concentrations of clothianidin. Of three drifted snow samples taken, the drift stratum containing the most wind-scoured soil had 0.16 and 0.20 ng/mL mainly clothianidin in the melted snow. The concentration was at the limit of detection (0.02 ng/mL taken across the entire vertical profile. With the exception of one sample, water samples tested had concentrations below those reported to have acute, chronic or sublethal effects to honey bees. Our results suggest that neonicotinoids may move off-target by wind erosion of contaminated soil. These results are informative to risk assessment models for other non-target species in maize

  18. Neonicotinoid Insecticide Residues in Surface Water and Soil Associated with Commercial Maize (Corn) Fields in Southwestern Ontario

    Science.gov (United States)

    Schaafsma, Arthur; Limay-Rios, Victor; Baute, Tracey; Smith, Jocelyn; Xue, Yingen

    2015-01-01

    Neonicotinoid insecticides have come under scrutiny for their potential unintended effects on non-target organisms, particularly pollinators in agro-ecosystems. As part of a larger study of neonicotinoid residues associated with maize (corn) production, 76 water samples within or around the perimeter of 18 commercial maize fields and neighbouring apiaries were collected in 5 maize-producing counties of southwestern Ontario. Residues of clothianidin (mean = 2.28, max. = 43.60 ng/mL) and thiamethoxam (mean = 1.12, max. = 16.50 ng/mL) were detected in 100 and 98.7% of the water samples tested, respectively. The concentration of total neonicotinoid residues in water within maize fields increased six-fold during the first five weeks after planting, and returned to pre-plant levels seven weeks after planting. However, concentrations in water sampled from outside the fields were similar throughout the sampling period. Soil samples from the top 5 cm of the soil profile were also collected in these fields before and immediately following planting. The mean total neonicotinoid residue was 4.02 (range 0.07 to 20.30) ng/g, for samples taken before planting, and 9.94 (range 0.53 to 38.98) ng/g, for those taken immediately after planting. Two soil samples collected from within an conservation area contained detectable (0.03 and 0.11 ng/g) concentrations of clothianidin. Of three drifted snow samples taken, the drift stratum containing the most wind-scoured soil had 0.16 and 0.20 ng/mL mainly clothianidin in the melted snow. The concentration was at the limit of detection (0.02 ng/mL) taken across the entire vertical profile. With the exception of one sample, water samples tested had concentrations below those reported to have acute, chronic or sublethal effects to honey bees. Our results suggest that neonicotinoids may move off-target by wind erosion of contaminated soil. These results are informative to risk assessment models for other non-target species in maize agro

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1979-10-01

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

  20. The effect of Bt-corn on soil invertebrates, soil microbial community and decomposition rates of corn post-harvest residues under field and laboratory conditions

    Czech Academy of Sciences Publication Activity Database

    Frouz, Jan; Elhottová, Dana; Helingerová, M.; Kocourek, F.

    2008-01-01

    Roč. 32, č. 4 (2008), s. 645-655 ISSN 1044-0046 Institutional research plan: CEZ:AV0Z60660521 Keywords : Bt corn * soil biology * decomposition Subject RIV: EH - Ecology, Behaviour Impact factor: 0.274, year: 2008

  1. 77 FR 50661 - Notice of Filing of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or...

    Science.gov (United States)

    2012-08-22

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

  2. Mechanical and Alkaline Hydrothermal Treated Corn Residue Conversion in to Bioenergy and Biofertilizer: A Resource Recovery Concept

    Directory of Open Access Journals (Sweden)

    Subhash Paul

    2018-02-01

    Full Text Available In this research fall time harvested corn residue (CR was first mechanically pretreated to produce 5 mm chopped and <500 µm ground particles, which underwent an anaerobic digestion (AD process to produce biomethane and biofertilizer. Another sample of CR was pretreated by an alkaline hydrothermal (HT process using 1%, 2% and 3% NaOH to produce solid biocarbon and the resulting alkaline hydrothermal process water (AHTPW, a co-product of biocarbon, underwent fast digestion under AD conditions to produce biomethane and biofertilizer. A predetermined HT process of 240 °C for 30 min was considered and the effect of alkali content on the HT process for biocarbon and biomethane product a rate of 8.21 MJ kg−1 and 9.23 MJ kg−1 of raw CR, respectively. Among the three selected alkaline HT processes, the 1% NaOH HT process produced the highest hybrid bioenergy of 11.39 MJ kg−1 of raw CR with an overall energy recovery of 62.82% of raw CR. The AHTPW of 2% and 3% NaOH HT-treated CR did not produce considerable amount of biomethane and their biocarbons contained 3.44 MJ kg−1 and 3.27 MJ kg−1 of raw CR of bioenergy, respectively. The biomethane produced from 5 mm chopped CR, <500 µm ground CR and 1% alkaline AHTPW for 30 days retention time were of 275.38 L kg−1 volatile solid (VS, 309.59 L kg−1 VS and 278.70 L kg−1 VS, respectively, compared to non-treated CR of 144–187 L kg−1 VS. Nutrient enriched AD digestate is useable as liquid fertilizer. Biocarbon, biomethane and biofertilizer produced from the 1% alkaline HT process at 240 °C for 30 min can reduce the greenhouse gas (GHG emissions of Ontario.

  3. 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

  4. Identification of multi-insecticide residues using GC-NPD and the degradation kinetics of chlorpyrifos in sweet corn and soils.

    Science.gov (United States)

    Wang, Peidan; Rashid, Muhammad; Liu, Jie; Hu, Meiying; Zhong, Guohua

    2016-12-01

    Because more than one insecticide is applied to crops to protect plants from pests, an analytical multi-residue determination method was developed using gas chromatography with a nitrogen phosphorus detector (GC-NPD). The retention time for 12 insecticides was 3.7-27.7min. Under the selected conditions, the limits of detection (LOD) and quantification (LOQ) were below the maximum residue limits (MRLs) and in the range of 0.00315-0.05μgmL(-1) and 0.01-0.165μgmL(-1), respectively. Using GC-NPD, we investigated the dissipation dynamics and final residual levels of chlorpyrifos in sweet corn and soil and determined that the half-lives was 4-7days, that is, that chlorpyrifos is safe to use on sweet corn with a pre-harvest interval of 16-22days before harvest. These results provide new insights into chlorpyrifos degradation in plants and its environmental behavior. Copyright © 2016. Published by Elsevier Ltd.

  5. [Determination of 32 sulfonylurea herbicide residues in sweet corns and green soybeans by QuEChERS-liquid chromatography-tandem mass spectrometry].

    Science.gov (United States)

    Wang, Lianzhu; Huang, Xiaoyan; Wang, Dengfei; Chen, Yong; Xu, Dunming; Zhou, Yu

    2015-05-01

    A fast method based on QuEChERS methodology for the simultaneous determination of 32 sulfonylurea herbicide residues in sweet corns and green soybeans was developed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The clean-up effects of three dispersive sorbents were evaluated in terms of the residue mass for extracts after evaporation and recoveries. The three sorbents were C18, a mixture of two sorbents--silica coated with zirconium dioxide (Z-Sep) and C18, a bonded C18 zirconia-coated silica (Z-Sep+). As a result, the best effects were obtained from using Z-Sep/C18 sorbents. The samples were extracted with acetonitrile, and salted out with anhydrous magnesium sulphate and sodium chloride. The extracts were cleaned up with dispersive solid phase extraction using Z-Sep/C18 sorbents. Chromatographic analysis was carried out using a CSH C18 column with gradient elution. The pesticides were analyzed by negative electrospray ionization tandem mass spectrometry under scheduled multiple reaction monitoring mode. The quantification was achieved using matrix-matched standard calibrations as the external standard. The recoveries at fortification levels of 10, 20, 100 µg/kg in sweet corns and green beans ranged from 80.0% to 108.2% with the relative standard deviations of 1.2%-13.0%. The limits of quantification (S/N ≥ 10) were 0.2-5.0 µg/kg. The method has been proven to be simple, sensitive, environmental, and thus suitable for the determination of the 32 sulfonylurea herbicide residues in sweet corns and green soy- beans.

  6. 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.

  7. In-field rates of decomposition and microbial communities colonizing residues vary by depth of residue placement and plant part, but not by crop genotype for residues from two Cry1AB Bt corn hybrids and their non-transgenic i

    Science.gov (United States)

    The adoption of Bt corn has been largely overshadowed by concerns about their unintended effects on human health and the environment. Residues of transgenic Bt crops decomposed more slowly than their non-transgenic isolines in one laboratory study, although no mechanism to explain these observations...

  8. Decomposição do resíduo de milho e variáveis relacionadas Corn crop residue decomposition and related parameters

    Directory of Open Access Journals (Sweden)

    I. Bertol

    2004-04-01

    Full Text Available A eficácia da semeadura direta na redução da erosão hídrica depende, em grande parte, da cobertura do solo ocasionada pelos resíduos das culturas. Objetivou-se determinar, entre agosto de 2001 e junho de 2002, em um Cambissolo Húmico alumínico léptico, situado entre 27 º 49 ' latitude Sul e 50 º 20 ' longitude Oeste de Greenwich, a decomposição do resíduo de milho. Os tratamentos, em três repetições, consistiram de: solo sem resíduo ou descoberto (SSR, solo com 8,77 Mg ha-1 de resíduo de milho (SR e solo com 8,77 Mg ha-1 de resíduo de milho mais 100 kg ha-1 de N (SR + N, avaliados em intervalos regulares de 30 dias. Determinou-se a quantidade do resíduo de milho, C orgânico e N total do referido resíduo. No solo, na camada de 0-0,03 m, foram avaliados C orgânico, N mineral, K trocável, pH em água, umidade e temperatura e, no ar, a temperatura a um metro acima da superfície do solo. O SR + N apresentou maior decomposição do resíduo de milho do que o SR, principalmente nos primeiros 120 dias, de tal modo que o tempo necessário para a quase que completa decomposição do resíduo (restando ainda cerca de 10 % da massa inicial seria de aproximadamente 1.300 dias, para o SR, e de aproximadamente 900 dias, para o SR + N.The efficacy of no-tillage systems in reducing water erosion depends largely on the soil cover by crop residues. The study was carried out in Santa Catarina State, Southern Brazil, from August 2001 to July 2002, aiming to evaluate the decay of corn residue on the surface of an Inseptisol and its influence on soil properties. The treatments, with three replicates, were: bare soil (BS, 8.77 Mg ha-1 of air dried corn residue (CR and 8.77 Mg ha-1 of air dried corn residue plus 100 kg ha-1 of nitrogen (CR + N. The remaining residue biomass on soil and its organic carbon and total nitrogen contents were evaluated every 30 days. It was also determined organic carbon, total nitrogen, potassium, pH, soil

  9. The Effects of Source and Rate of Nitrogen Fertilizer and Irrigation on Nitrogen Uptake of Silage Corn and Residual Soil Nitrate

    Directory of Open Access Journals (Sweden)

    M. A. Khodshenas

    2016-09-01

    Full Text Available Introduction: Growing irrigation demand for corn production, along side with draws of ground water from stressed water sources, should be limited due to scarce resources and environmental protection aspects. Nitrogen fertilizer applied at rates higher than the optimum requirement for crop production may cause an increase in nitrate accumulation below the root zone and pose a risk of nitrate leaching. Improving nitrogen management for corn production has a close relation with soil water content. In this study, we investigated the effects of source and rate of nitrogen fertilizer and irrigation on silage corn production and nitrogen concentration, nitrogen uptake and residual soil nitrate in two depths. Materials and Methods: This experiment carried out as split spli- plot in a Randomized Complete Block design (RCBD with three replications, in Arak station (Agricultural research center of markazi province, 34.12 N, 49.7 E; 1715 m above mean sea level during three years. The soil on the site was classified as a Calcaric Regosols (loamy skeletal over fragmental, carbonatic, thermic, calcixerollic xerochrepts. Main plots were irrigation treatments based on 70, 100 and 130 mm cumulative evaporation from A class Pan. Sub plots were two kinds of nitrogen fertilizers (Urea and Ammonium nitrate and sub sub-plots were five levels of nitrogen rates (0, 100, 200, 300 and 400 kgN.ha-1. Nitrogen fertilizer rates were split into three applications: 1/3 was applied at planting, 1/3 at 7-9 leaf stage and 1/3 remainder was applied before tasseling as a banding method. Phosphorus was applied at a rate of 150 kg.ha-1in each season and potassium at a rate of 30kg.ha-1 (only in first growth season based on soil testing as triple super phosphate and potassium sulfate, respectively. The corn variety of single cross 704 was planted at 20 m2 plots. The plants were sampled at dough stage from the two rows and weighted in each plot. Plant samples were dried in a forced air

  10. 40 CFR 180.507 - Azoxystrobin; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... 12.0 Corn, field, grain 0.05 Corn, field, refined oil 0.3 Corn, field, stover 25.0 Corn, pop, grain 0... Peanut, refined oil 0.6 Pecan 0.01 Peppermint, tops 30 Persimmon 2.0 Pistachio 0.50 Potato 0.03 Pulasan 2... Tomato 0.2 Tomato, paste 0.6 Turnip, greens 25 Vegetable, foliage of legume, group 7 30.0 Vegetable...

  11. Biomass supply from alternative cellulosic crops and crop residues: A spatially explicit bioeconomic modeling approach

    International Nuclear Information System (INIS)

    Egbendewe-Mondzozo, Aklesso; Swinton, Scott M.; Izaurralde, César R.; Manowitz, David H.; Zhang, Xuesong

    2011-01-01

    This paper introduces a spatially-explicit bioeconomic model for the study of potential cellulosic biomass supply. For biomass crops to begin to replace current crops, farmers must earn more from them than from current crops. Using weather, topographic and soil data, the terrestrial ecosystem model, EPIC, dynamically simulates multiple cropping systems that vary by crop rotation, tillage, fertilization and residue removal rate. EPIC generates predicted crop yield and environmental outcomes over multiple watersheds. These EPIC results are used to parameterize a regional profit-maximization mathematical programming model that identifies profitable cropping system choices. The bioeconomic model is calibrated to 2007–09 crop production in a 9-county region of southwest Michigan. A simulation of biomass supply in response to rising biomass prices shows that cellulosic residues from corn stover and wheat straw begin to be supplied at minimum delivered biomass:corn grain price ratios of 0.15 and 0.18, respectively. At the mean corn price of $162.6/Mg ($4.13 per bushel) at commercial moisture content during 2007–2009, these ratios correspond to stover and straw prices of $24 and $29 per dry Mg. Perennial bioenergy crops begin to be supplied at price levels 2–3 times higher. Average biomass transport costs to the biorefinery plant range from $6 to $20/Mg compared to conventional crop production practices in the area, biomass supply from annual crop residues increased greenhouse gas emissions and reduced water quality through increased nutrient loss. By contrast, perennial cellulosic biomass crop production reduced greenhouse gas emissions and improved water quality. -- Highlights: ► A new bioeconomic model predicts biomass supply and its environmental impacts. ► The model captures the opportunity cost of switching to new cellulosic crops. ► Biomass from crop residues is supplied at lower biomass price than cellulosic crops. ► Biomass from cellulosic crops has

  12. Synergistic action of enzyme preparations towards recalcitrant corn silage polysaccharides

    NARCIS (Netherlands)

    Neumüller, K.G.; Streekstra, H.; Schols, H.A.; Gruppen, H.

    2014-01-01

    Corn silage, its water unextractable solids (WUS) and enzyme recalcitrant solids (ErCS) and an industrial corn silage-based anaerobic fermentation residue (AFR) represent corn substrates with different levels of recalcitrance. Compositional analysis reveals different levels of arabinoxylan

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

    Science.gov (United States)

    Liu, Gang; Bao, Jie

    2017-11-01

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

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

    African Journals Online (AJOL)

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

  15. Alcohol production from agricultural and forestry residues

    Energy Technology Data Exchange (ETDEWEB)

    Dale, L; Opilla, R; Surles, T

    1980-09-01

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

  16. Alcohol production from agricultural and forestry residues

    Energy Technology Data Exchange (ETDEWEB)

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

    1980-05-01

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

  17. 40 CFR 180.442 - Bifenthrin; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... Corn, sweet, kernel plus cob with husk removed 0.05 Corn, sweet, stover 5.0 Cotton, undelinted seed 0.5... with the following prescribed conditions: (A) Application shall be limited to general surface and spot... treated. Spot and/or crack and crevice application may be used while the facility is in operation provided...

  18. Economics of Electrical Energy from Crop Residue Combustion with High Sulfur Coal

    OpenAIRE

    F. J. Hitzhusen; Mohammed Abdallah

    1980-01-01

    The economic feasibility of utilizing corn stover as a coal supplement in small to medium-sized, coal-burning steam-electric plants appears promising, particularly when the low sulfur emission value of corn stover is considered. Two case steam-electric power plants located in Ames, Iowa, and Peru, Indiana, are analyzed utilizing three harvest and collection systems and alternative values for several key technical and economic parameters. These results combined with data from a sample of steam...

  19. 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

  20. Thermal Pretreatment of Harvest Residues and Their Use in Anaerobic Co-digestion with Dairy Cow Manure.

    Science.gov (United States)

    Kovačić, Đurđica; Kralik, Davor; Jovičić, Daria; Rupčić, Slavko; Popović, Brigita; Tišma, Marina

    2018-02-01

    Several batch experiments were conducted on the anaerobic co-digestion of dairy cow manure (DCM) with three harvest residues (HR) (soybean straw, sunflower stalks, and corn stover). The influence of thermal pretreatment of HR on biogas production was investigated, where the HR were thermally pretreated at two different temperatures: T = 121 °C and T = 175 °C, during t = 30 and t = 90 min, respectively. All anaerobic co-digestion batch experiments were performed simultaneously under thermophilic regime, at T = 55 °C. Biogas and methane yields were significantly improved in experiments performed with corn stover thermally pretreated at 175 °C for 30 min (491.37 cm 3 /g VS and 306.96 cm 3 /g VS, respectively), if compared to experiments performed with untreated corn stover. The highest VS and COD removal rates were also observed in the same group of experiments and were 34.5 and 50.1%, respectively. The highest biogas and methane yields with soybean straw (418.93 cm 3 /g VS and 261.44 cm 3 /g VS, respectively) were obtained when soybean straw pretreated at 121 °C during 90 min. The highest biogas and methane yields with sunflower stalk (393.28 cm 3 /g VS and 245.02 cm 3 /g VS, respectively) were obtained when sunflower stalk was pretreated at 121 °C during 90 min.

  1. Technoeconomic and Policy Analysis for Corn Stover Biofuels

    OpenAIRE

    Petter, Ryan; Tyner, Wallace E.

    2014-01-01

    Conventional fossil fuels dominate the marketplace, and their prices are a direct competitor for drop-in biofuels. This paper examines the impact of fuel selling price uncertainty on investment risk in a fast pyrolysis derived biofuel production facility. Production cost specifications are gathered from previous research. Monte Carlo analysis is employed with uncertainty in fuel selling price, biomass cost, bio-oil yield, and hydrogen price parameters. Experiments reveal that fuel price has a...

  2. 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

    Bioethanol derived from lignocellulosic biomass has the potential to replace gasoline. Cellulose is naturally recalcitrant to enzymatic attack, and it also surrounded by the matrix of xylan and lignin, which enhances the recalcitrance. Therefore, lignocellulosic materials must be pretreated to make...

  3. Rheological modification of corn stover biomass at high solids concentrations

    Science.gov (United States)

    Joseph R. Samaniuk; C. Tim Scott; Thatcher W. Root; Daniel J. Klingenberg

    2012-01-01

    Additives were tested for their ability to modify the rheology of lignocellulosic biomass. Additive types included water-soluble polymers (WSPs), surfactants, and fine particles. WSPs were the most effective rheological modifiers, reducing yield stresses of concentrated biomass by 60–80% for additive concentrations of 1–2 wt. % (based on mass of dry biomass solids)....

  4. Bioprocessing of agricultural residues to ethanol utilizing a cellulolytic extremophile.

    Science.gov (United States)

    Zambare, Vasudeo P; Bhalla, Aditya; Muthukumarappan, Kasiviswanath; Sani, Rajesh K; Christopher, Lew P

    2011-09-01

    A recently discovered thermophilic isolate, Geobacillus sp. R7, was shown to produce a thermostable cellulase with a high hydrolytic potential when grown on extrusion-pretreated agricultural residues such corn stover and prairie cord grass. At 70°C and 15-20% solids, the thermostable cellulase was able to partially liquefy solid biomass only after 36 h of hydrolysis time. The hydrolytic capabilities of Geobacillus sp. R7 cellulase were comparable to those of a commercial cellulase. Fermentation of the enzymatic hydrolyzates with Saccharomyces cerevisiae ATCC 24860 produced ethanol yields of 0.45-0.50 g ethanol/g glucose with more than 99% glucose utilization. It was further demonstrated that Geobacillus sp. R7 can ferment the lignocellulosic substrates to ethanol in a single step that could facilitate the development of a consolidated bioprocessing as an alternative approach for bioethanol production with outstanding potential for cost reductions.

  5. Three amino acid residues bind corn odorants to McinOBP1 in the polyembryonic endoparasitoid of Macrocentrus cingulum Brischke.

    Directory of Open Access Journals (Sweden)

    Tofael Ahmed

    Full Text Available Odorant binding proteins (OBPs play a central role in transporting odorant molecules from the sensillum lymph to olfactory receptors to initiate behavioral responses. In this study, the OBP of Macrocentrus cingulum McinOBP1 was expressed in Escherichia coli and purified by Ni ion affinity chromatography. Real-time PCR experiments indicate that the McinOBP1 is expressed mainly in adult antennae, with expression levels differing by sex. Ligand-binding experiments using N-phenyl-naphthylamine (1-NPN as a fluorescent probe demonstrated that the McinOBP1 can bind green-leaf volatiles, including aldehydes and terpenoids, but also can bind aliphatic alcohols with good affinity, in the order trans-2-nonenal>cis-3-hexen-1-ol>trans-caryophelle, suggesting a role of McinOBP1 in general odorant chemoreception. We chose those three odorants for further homology modeling and ligand docking based on their binding affinity. The Val58, Leu62 and Glu130 are the key amino acids in the binding pockets that bind with these three odorants. The three mutants, Val58, Leu62 and Glu130, where the valine, leucine and glutamic residues were replaced by alanine, proline and alanine, respectively; showed reduced affinity to these odorants. This information suggests, Val58, Leu62 and Glu130 are involved in the binding of these compounds, possibly through the specific recognition of ligands that forms hydrogen bonds with the ligands functional groups.

  6. 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.

  7. Desempenho de genótipos de milho cultivados com diferentes quantidades de palha de aveia-preta e doses de nitrogênio Corn genotype performance under black oat crop residues and nitrogen fertilization

    Directory of Open Access Journals (Sweden)

    Ademir de Oliveira Ferreira

    2009-02-01

    Full Text Available O objetivo deste trabalho foi avaliar a resposta de genótipos de milho (Zea mays L., cultivado em sistema de plantio direto, a diferentes quantidades de palha de aveia-preta (Avena strigosa Schreb. e doses de nitrogênio. O experimento foi conduzido em um Latossolo Vermelho eutrófico, em delineamento experimental de blocos ao acaso em parcelas subsubdivididas, com três repetições. As parcelas principais foram representadas pelas quantidades de palha na superfície do solo (sem palha, 5,16 e 10,32 mg ha-1. As subparcelas foram representadas por três genótipos de milho e as subsubparcelas constituíram-se das doses 0, 60, 120, 180 e 240kg ha-1 de nitrogênio. O aumento da dose de nitrogênio reduziu a requeima das folhas e promoveu o suprimento adequado de nitrogênio das plantas de milho em todos os tratamentos com palha de aveia-preta. Os genótipos de milho diferenciaram-se quanto à produtividade de grãos, ao aproveitamento do nitrogênio mineralizado da palha e ao comprimento do sistema radicular, quando submetidos a diferentes quantidades de palha de aveia-preta e de nitrogênio.The objective of this work was to assess the performance of corn (Zea maysL. genotypes as affected by inputs of black oat (Avena strigosa Schreb. residues applied on the soil surface and nitrogen fertilization under no-tillage system in a Typical Haplustox. The experiment was carried out in a complete randomized block design, arranged in split-split plots with three replicates. The main plots consisted of the amount of crop residues on the soil surface (no crop residue, 5.16 and 10.32 mg ha-1. The split plots were three corn genotypes, and the split-split plots were five nitrogen rates: 0, 60, 120, 180, and 240kg ha-1. An increase in the nitrogen rates decreased nitrogen deficiency and provided an adequate nitrogen supply for corn, under all the amounts of black oat residues. The corn genotypes grown with different amounts of black oat residues and nitrogen

  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

    Biofuels represent an opportunity for domestic fuel production from renewable energy sources with potential environmental and social benefits such as reducing greenhouse gas (GHG) and promoting rural development. However, as demand for biofuel continues to increase worldwide, concerns about land competition between food and fuel, excessive water usage and other unintended environmental consequences have grown. Through a comparative study between US corn ethanol and Brazilian sugarcane ethanol, we examine the energy, land, water and GHG performance of the two largest industrial fuel ethanol production systems in the world. Our comparisons include current and potential future systems with improved agronomic practices, crop yields, ethanol conversion processes, and utilization of agricultural residues. Our results suggest that the average water footprints of US corn ethanol and Brazilian sugarcane ethanol are fairly close (108 and 110 m3/GJ of ethanol, respectively) while the variations can range from 50 to 250 m3/GJ for sugarcane ethanol and 50 to380 m3/GJ for corn ethanol. Results emphasize the need to examine the water footprint within the context of local and regional climatic variability, water availability, competing uses (e.g. agricultural, industrial, and municipal water needs) and other ecosystem constraints. Research is under way (at the National Renewable Energy Laboratory and other institutions) to develop models to analyze water supply and demand at the watershed-scale for current and future biomass production, and to understand the tradeoffs among water supply, demand and quality due to more intensive agricultural practices and expansion of biofuels. Land use efficiency metrics, with regards to life cycle GHG emissions (without land use change) savings through gasoline displacement with ethanol, illustrate the progression of the biofuel industry and the importance of maximizing bioenergy production by utilizing both the crops and the residues. A recent

  9. The Effects of Source and Rate of Nitrogen Fertilizer and Irrigation on Nitrogen Uptake of Silage Corn and Residual Soil Nitrate

    OpenAIRE

    M. A. Khodshenas; J. Ghadbeiklou; M. Dadivar

    2016-01-01

    Introduction: Growing irrigation demand for corn production, along side with draws of ground water from stressed water sources, should be limited due to scarce resources and environmental protection aspects. Nitrogen fertilizer applied at rates higher than the optimum requirement for crop production may cause an increase in nitrate accumulation below the root zone and pose a risk of nitrate leaching. Improving nitrogen management for corn production has a close relation with soil water conten...

  10. 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%

  11. Safety, health, and environmental assessment of bioethanol production from sugarcane, corn, and corn stover

    OpenAIRE

    Banimostafa, Alireza; Nguyen, Thuy Thi Hong; Kikuchi, Yasunori; Papadokonstantakis, Stavros; Sugiyama, Hirokazu; Hirao, Masahiko; Hungerbühler, Konrad

    2017-01-01

    Biofuels as renewable resources are one of the options to meet the challenges of fossil fuel resource depletion and atmospheric pollution. Several studies have focused on the technical, economic, and environmental footprint of biofuels, particularly bioethanol production. However, there has been little effort to incorporate the environmental, health, and safety (EHS) hazards in an inclusive sustainability assessment of bioethanol production alternatives. This study focuses on these sustainabi...

  12. Economic, environmental and social assessment of briquette fuel from agricultural residues in China – A study on flat die briquetting using corn stalk

    International Nuclear Information System (INIS)

    Hu, Jianjun; Lei, Tingzhou; Wang, Zhiwei; Yan, Xiaoyu; Shi, Xinguang; Li, Zaifeng; He, Xiaofeng; Zhang, Quanguo

    2014-01-01

    Biomass can be relatively easily stored and transported compared with other types of renewable energy sources. Crop straw can be converted into densified solid biofuel via briquette fuel technology to expand its possible applications and enhance its utilisation efficiency. However, the potential economic, environmental and social impacts of crop straw briquette fuel need to be assessed before its large-scale use. This paper provides a comprehensive evaluation of these impacts for a fully-operating 2 × 10 4 t/a corn stalk briquette fuel plant in China. The results show that with a life time of 15 years, a purchase price of 150 RMB/t for corn stalk and the current sales price of 400 RMB/t for briquette fuel, the plant has a net present value of 9.6 million RMB or 1.5 million USD, an internal rate of return of 36% and a short investment payback period of 4.4 years. The life cycle greenhouse gas emissions are found to be 323 t CO 2 ,e/year or 1 kg CO 2 ,e/GJ, much lower than that of coal. Additionally, the process reduces pollution by decreasing the amount of corn stalk that is discarded or burnt directly in the field. In terms of social impacts, the use of corn stalk briquetting fuel plant is expected to play an important role in increasing local residents' income, improving rural ecological environments, alleviating energy shortages, guaranteeing energy security, and promoting socialism new rural reconstruction. - Highlights: • A fully-operating 2 × 10 4 t/a corn stalk briquette fuel plant in China is analysed. • The plant has net present value of $1.5 million and payback period of 4.4 years. • Life cycle GHG emissions are 323 t CO 2 ,e/year or 1 kg CO 2 ,e/GJ, much lower than coal. • The plant will also have significant social benefits

  13. Rugosidade superficial do solo sob diferentes doses de resíduo de milho submetido à chuva simulada Soil surface roughness with different doses of corn residue submitted to simulated rainfall

    Directory of Open Access Journals (Sweden)

    Ildegardis Bertol

    2007-01-01

    Full Text Available O objetivo deste trabalho foi avaliar a rugosidade e a tortuosidade da superfície do solo, preparado com diferentes doses de resíduo cultural de milho, e relacioná-las com o volume de chuva simulada. Em um Cambissolo, em La Coruña, Espanha, em agosto de 2005, avaliou-se a rugosidade superficial, no preparo mínimo sob chuva simulada, com as doses de 0, 2, 4, 6 e 8 t ha-1 de resíduo de milho picado e semi-incorporado ao solo. Aplicaram-se oito testes de chuva simulada, com 65 mm h-1 e 60 min cada um. A rugosidade e a tortuosidade, ao acaso, foram menores do que na condição linear e, as desta condição foram menores do que na condição original. A redução da rugosidade e da tortuosidade, em decorrência das chuvas, diminuiu com o aumento da dose de resíduo de milho. A rugosidade superficial foi mais fortemente influenciada quando se eliminou o efeito da declividade do terreno do que quando se eliminaram, simultaneamente, os efeitos da declividade e das marcas de preparo do solo para o seu cálculo.The objective of this work was to determine the surface roughness and the tortuosity of the soil tilled with different doses of corn residues, and to relate them to simulated rainfall volume. In an Inceptisol, in La Coruña, Spain, in August of 2005, the surface roughness and tortuosity were evaluated in the minimum soil tillage system under simulated rain, with the doses 0, 2, 4, 6, and 8 t ha-1 of corn residues semi-incorporated to the soil for manual tillage. Eight tests of simulated rain were applied, with 65 mm h-1 and 60 min each one. The surface roughness and tortuosity were determined before the application of the residue, immediately after the soil tillage and immediately after the 1st, 2nd, 4th, 6th and 8th tests of the rain. The reduction of the roughness and of the tortuosity, due to rain, decreased with the increase of corn residues doses. The superficial roughness was more strongly influenced, when the effect of land steepness

  14. 76 FR 10584 - Notice of Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or...

    Science.gov (United States)

    2011-02-25

    ... ppm; ti palm, leaves at 13 ppm; root and tuber vegetables, group 1 at 0.35 ppm; leaves of root and... 0.6 ppm; corn, field, stover at 2.5 ppm; corn, field, refined oil at 0.03 ppm; corn, pop, grain at 0... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-OPP-2011-0082; FRL-8863-3] Notice of Receipt of Several...

  15. Efeito da palha e da mistura atrazine e metolachlor no controle de plantas daninhas na cultura do milho, em sistema de plantio direto Effect of corn plant residue and mixture of atrazine plus metolachlor on the weeds control in no-till corn system

    Directory of Open Access Journals (Sweden)

    Maurílio Fernandes de Oliveira

    2001-01-01

    Full Text Available O objetivo deste trabalho foi estudar o efeito de níveis de palha de milho e da mistura formulada atrazine e metolachlor no controle de plantas daninhas na cultura de milho, em sistema de plantio direto. O ensaio foi realizado num Latossolo Vermelho distrófico, argiloso, fase cerrado, sendo a dessecação do mato feita com glyphosate, 15 dias antes do plantio. O delineamento experimental utilizado foi o de blocos ao acaso, com parcelas subdivididas e com três repetições. Antes do plantio do milho, distribuíram-se cinco níveis de palha de milho (0, 3, 6, 9 e 12 tha-1, nas parcelas, de modo uniforme. Nas subparcelas, após o plantio, foram considerados dois tratamentos referentes a herbicida: ausência de herbicida ou a dose de 6,0 Lha-1 de atrazine, e metolachlor (1.200+ 1.800gha-1. Avaliou-se o número das plantas daninhas, por espécie, aos 26 e 41 dias após o plantio. O número total de plantas daninhas foi reduzido significativamente pelos níveis de palha, independentemente da presença do herbicida e da época de avaliação. O herbicida não apresentou efeito significativo na primeira época de avaliação; entretanto, na segunda, a redução no número total de plantas daninhas foi de, aproximadamente, 53% em relação às parcelas que não o receberam. A população total de planta daninha foi significativamente superior na segunda avaliação, na ausência do herbicida. Na presença do herbicida, não houve diferença significativa na população total de invasoras entre as duas épocas de avaliação.The objective of this work was to study the effect of corn plant residue and mixture of atrazine plus metolachlor on weed control in no-till corn system. This experiment was performed in an Oxisol, and the weed desiccation was done using glyphosate, 15 days before planting. The experimental design was a randomized block, with three replications. Before corn planting, five levels of corn plant residues (0, 3, 6, 9 e 12tha-1 were

  16. 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)

  17. 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.

  18. Determination of chlorantraniliprole residues in crops by liquid chromatography coupled with atmospheric pressure chemical ionization mass spectrometry/mass spectrometry.

    Science.gov (United States)

    Grant, Joann; Rodgers, Carol A; Chickering, Clark D; Hill, Sidney J; Stry, James J

    2010-01-01

    An analytical method is presented for the determination of chlorantraniliprole residues in crops. Chlorantraniliprole residues were extracted from crop matrixes with acetonitrile after a water soak. The extracts were passed through a strong anion-exchange (SAX) SPE cartridge stacked on top of a reversed-phase (RP) polymer cartridge. After both cartridges were rinsed and vacuum-dried, the SAX cartridge was removed, and chlorantraniliprole was eluted from the RP polymer cartridge with acetonitrile. The acetonitrile eluate was evaporated to dryness, reconstituted, and analyzed using an LC/MS/MS instrument equipped with an atmospheric pressure chemical ionization source. The method was successfully validated at 0.010, 0.10, and 10 mg/kg for the following crop matrixes: potatoes, sugar beets (tops), lettuce, broccoli, soybeans, soybean forage, tomatoes, cucumbers, oranges, apples, pears, peaches, almonds (nutmeat), rice grain, wheat grain, wheat hay, corn stover, alfalfa forage, cottonseed, grapes, and corn grain. The average recoveries from all crop samples fortified at the method LOQ ranged from 91 to 108%, with an overall average recovery of 97%. The average recoveries from all crop samples fortified at 10 times the method LOQ ranged from 89 to 115%, with an overall average recovery of 101%. For all of the fortified control samples analyzed in this study, the overall average recovery was 99%.

  19. Glyphosate Mineralization: Effect of Temperature and Soybean and Corn Crop Residues Mineralización de Glifosato: Efecto de la Temperatura y los Residuos Vegetales de Soya y Maíz

    Directory of Open Access Journals (Sweden)

    Ariel Rampoldi

    2008-03-01

    Full Text Available Mineralization is the main mechanism of dissipation of glyphosate herbicide (N-[phosphonomethyl] glycine in soil. However, there is scarce information about the mineralization process in strata formed by stubbles in no-tillage systems. The kinetics and rate of mineralization of herbicide in stubbles of soybean (Glycine max L. Merr. and corn (Zea mays L. were investigated. To evaluate the effect of age of crop residues, samples of soybean stubbles were collected immediately after harvest (Soja 1 and four months after harvest (Soja 2. Corn crop residues were collected three months after harvest. Glyphosate evolution and total microbial activity (TMA were monitored by release of 14C-CO2 and C-CO2 under laboratory conditions with two temperatures, 15 and 28 ºC. Crop residues size was evaluated using grinding (1 mm and cut (1 to 2 cm stubbles. Results showed that glyphosate mineralization was affected by the incubation temperature and the origin and age of crop residues. Size of crop residues did not modify glyphosate mineralization. Average glyphosate mineralization after 56 days of incubation at 15 and 28 ºC was of 3.9 and 9.9%, respectively, of the 14C-glyphosate initially applied. In maize crop residues the percentages were 2.0 and 3.0%, respectively, at 15 and 28 ºC. A similar evolution was detected for TMA. The co-metabolic nature of glyphosate mineralization was corroborated. An inverse relation between C/N ratio and glyphosate mineralization was detected. Higher glyphosate mineralization was detected in fresh soybean stubbles, suggesting that applications on aged crop residues could increase the persistence of glyphosate in no-tillage systemsLa mineralización es el principal mecanismo de disipación del herbicida glifosato (N-[fosfonometil] glicina en el suelo. Existe escasa información sobre el proceso de mineralización de glifosato en el estrato formado por rastrojos en suelos cultivados en sistema de siembra directa. Las muestras de

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

    International Nuclear Information System (INIS)

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

    1998-01-01

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

  1. Efeito da aplicação de águas residuárias de suinocultura sobre a produção do milho para silagem Effect of swine wastewater application on corn production for silage

    Directory of Open Access Journals (Sweden)

    Wallisson da S. Freitas

    2004-04-01

    Full Text Available Este trabalho foi conduzido com o objetivo de se avaliar o efeito da aplicação de quatro lâminas de água e águas residuárias de suinocultura, bruta e peneirada, sobre os componentes de produção da cultura do milho (Zea mays L. para silagem. Foram instalados 24 lisímetros de percolação, sendo que em 8 deles se aplicou água (A, em 8 água residuária bruta (ARB e nos demais água residuária peneirada (ARP. As lâminas aplicadas correspondiam a 0,5, 1,0, 1,5 e 2,0 ET0. A colheita foi realizada 140 dias após o plantio, quando se avaliaram os componentes de produção: altura de plantas, peso, altura, produtividade e índice de espigas e produtividade de matéria verde. As produtividades médias de matéria verde nos tratamentos com ARB e ARP foram equivalente a 45 e 46 t ha-1, cerca de 51 e 52% superiores à testemunha, respectivamente. A aplicação das águas residuárias de suinocultura aumentou significativamente os valores de altura de plantas, índice de espigas, altura de espigas e peso de espigas. Em geral, o peneiramento das águas residuárias e as diferentes lâminas aplicadas não afetaram os parâmetros de produção do milho para silagem.This work was carried out with the objective of evaluating the effect of four depths of water and swine wastewater-gross and after sieving, on production of corn (Zea mays, L. for silage. Water was applied in eight lysimeters, in other eight gross swine wastewater (ARB was applied and the sieved pig wastewater (ARP on the other eight. The depths applied corresponded to 0.5, 1.0, 1.5 and 2.0 times of the reference evapotranspiration. The production components, height of the plants, height of spikes, spike index, productivity of spikes and productivity of green matter were evaluated 140 days after sowing. The mean productivities of green matter in the treatments with ARB and ARP were equivalent to 45 and 46 t ha-1, corresponding to, respectively, 51 and 52% higher than the productivity in

  2. Assessing plant residue decomposition in soil using DRIFT spectroscopy

    Science.gov (United States)

    Ouellette, Lance; Van Eerd, Laura; Voroney, Paul

    2016-04-01

    Assessment of the decomposition of plant residues typically involves the use of tracer techniques combined with measurements of soil respiration. This laboratory study evaluated use of Diffuse Reflectance Fourier Transform (DRIFT) spectroscopy for its potential to assess plant residue decomposition in soil. A sandy loam soil (Orthic Humic Gleysol) obtained from a field research plot was passed through a 4.75 mm sieve moist (~70% of field capacity) to remove larger crop residues. The experimental design consisted of a randomized complete block with four replicates of ten above-ground cover crop residue-corn stover combinations, where sampling time was blocked. Two incubations were set up for 1) Drift analysis: field moist soil (250 g ODW) was placed in 500 mL glass jars, and 2) CO2 evolution: 100 g (ODW) was placed in 2 L jars. Soils were amended with the plant residues (oven-dried at 60°C and ground to <2 mm) at rates equivalent to field mean above-ground biomass yields, then moistened to 60% water holding capacity and incubated in the dark at 22±3°C. Measurements for DRIFT and CO2-C evolved were taken after 0.5, 2, 4, 7, 10, 15, 22, 29, 36, 43, 50 64 and 72 d. DRIFT spectral data (100co-added scans per sample) were recorded with a Varian Cary 660 FT-IR Spectrometer equipped with an EasiDiff Diffuse Reflectance accessory operated at a resolution of 4 cm-1 over the mid-infrared spectrum from 4000 to 400 cm-1. DRIFT spectra of amended soils indicated peak areas of aliphatics at 2930 cm-1, of aromatics at 1620, and 1530 cm-1 and of polysaccharides at 1106 and 1036 cm-1. Evolved CO2 was measured by the alkali trap method (1 M NaOH); the amount of plant residue-C remaining in soil was calculated from the difference in the quantity of plant residue C added and the additional CO2-C evolved from the amended soil. First-order model parameters of the change in polysaccharide peak area over the incubation were related to those generated from the plant residue C decay

  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. 77 FR 30481 - Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or on Various...

    Science.gov (United States)

    2012-05-23

    ...); dried shelled pea and bean, except soybean (subgroup 6C); corn, grain; corn, corn, sweet; soybeans; and... Method No. Meth-160, Revision 2. Residues are quantified by GC equipped with a nitrogen-phosphorous...

  5. 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.

  6. 40 CFR 180.184 - Linuron; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... Corn, sweet, stover 6.0 Cotton, gin byproducts 5.0 Cotton, undelinted seed 0.25 Goat, fat 0.2 Goat, kidney 2.0 Goat, liver 2.0 Goat, meat 0.1 Goat, meat byproducts except kidney and liver 0.1 Hog, fat 0.05... 0.1 Horse, meat byproducts except kidney and liver 0.1 Milk 0.05 Parsnip, roots 0.05 Parsnip, tops 0...

  7. 40 CFR 180.185 - DCPA; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... 5.0 Watermelon 1.0 (b) Section 18 emergency exemptions. [Reserved] (c) Tolerances with regional...: Commodity Parts per million Basil, dried leaves 20.0 Basil, fresh leaves 5.0 Bean, dry 2.0 Bean, mung, seed... husks removed 0.05 Corn, sweet, stover 0.4 Cotton, undelinted seed 0.2 Cucumber 1.0 Dill 5.0 Eggplant 1...

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

    Directory of Open Access Journals (Sweden)

    Venkateswarulu Swarna

    2015-06-01

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

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

    African Journals Online (AJOL)

    user

    2011-02-01

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

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

    African Journals Online (AJOL)

    Dr Grace Tona

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

  11. 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 ...

  12. 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

  13. Delaying corn rootworm resistance to Bt corn.

    Science.gov (United States)

    Tabashnik, Bruce E; Gould, Fred

    2012-06-01

    Transgenic crops producing Bacillus thuringiensis (Bt) toxins for insect control have been successful, but their efficacy is reduced when pests evolve resistance. To delay pest resistance to Bt crops, the U.S. Environmental Protection Agency (EPA) has required refuges of host plants that do not produce Bt toxins to promote survival of susceptible pests. Such refuges are expected to be most effective if the Bt plants deliver a dose of toxin high enough to kill nearly all hybrid progeny produced by matings between resistant and susceptible pests. In 2003, the EPA first registered corn, Zea mays L., producing a Bt toxin (Cry3Bb1) that kills western corn rootworm, Diabrotica virgifera virgifera LeConte, one of the most economically important crop pests in the United States. The EPA requires minimum refuges of 20% for Cry3Bb1 corn and 5% for corn producing two Bt toxins active against corn rootworms. We conclude that the current refuge requirements are not adequate, because Bt corn hybrids active against corn rootworms do not meet the high-dose standard, and western corn rootworm has rapidly evolved resistance to Cry3Bb1 corn in the laboratory, greenhouse, and field. Accordingly, we recommend increasing the minimum refuge for Bt corn targeting corn rootworms to 50% for plants producing one toxin active against these pests and to 20% for plants producing two toxins active against these pests. Increasing the minimum refuge percentage can help to delay pest resistance, encourage integrated pest management, and promote more sustainable crop protection.

  14. Quantitative analysis of dicamba residues in raw agricultural commodities with the use of ion-pairing reagents in LC-ESI-MS/MS.

    Science.gov (United States)

    Guo, Hongyue; Riter, Leah S; Wujcik, Chad E; Armstrong, Daniel W

    2016-01-01

    A sensitive and selective HPLC-MS/MS method was developed for the quantitative analysis of dicamba residues in raw agricultural commodities (RACs). Instead of analysis in the traditionally used negative electrospray ionization (ESI) mode, these anionic compounds were detected in positive ESI with the use of ion-pairing reagents. In this approach, only a small amount (60µM) of a commercially available dicationic ion-pairing reagent was introduced into the post-column sample stream. This method has been validated in six different types of RACs including corn grain, corn stover, cotton seed, soybean, soy forage and orange with satisfactory quantitative accuracy and precision. The limits of quantitation (LOQ) values for these analytes were 1.0 to 3.0µg/kg. The standard curves were linear over the range of the tested concentrations (3.0 to 500µg/kg), with correlation coefficient (r) values≥0.999. Evaluation of ionization effects in RAC matrix extracts using diluent blanks for comparison showed no significant matrix effects were present. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. 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…

  16. Efeito residual da adubação verde no rendimento de brócolo (Brassica oleraceae L. var. Italica cultivado em sucessão ao milho (Zea mays L. Residual effect of the green manures in broccoli (Brassica oleraceae var. Italica yield cultivated in succession to corn (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Adriano Perin

    2004-12-01

    residual effects of the single and intercropped sunnhemp (Crotalaria juncea and millet (Pennisetum americanum as green manures on nitrogen transfer and yield of broccoli crop in succession to corn in absence and presence of fertilization of 150kg ha-1 of N. The experiment is a randomized block in split plot design and four replicates. The plot treatments were the previous cultivation of sunnhemp, millet, sunnhemp + millet and spontaneous vegetation. On subplots, the treatments were 150kg ha-1 of N and control (absence of N-fertilizer on broccoli. The succession involved the cultivation of the green manures (September, 26th, 2001 to December, 03th, 2001, followed by corn crop (December, 04th, 2001 to May, 28th, 2002 and broccoli hybrid Big Sur (June, 05th, 2002 to August, 10th, 2002 in zero tillage on the corn residues. It was not detected residual effect of the green manures on the diameter, dry weight of flower buds and dry mass yield of broccoli, either in the absence or presence of N-fertilizer. The presence of the single sunnhemp on crop rotation elevated the content and accumulation of N in the leaves and flower buds of broccoli, either in the absence or presence of 150kg ha-1 of N. In the intercrop sunnhemp and millet, the presence of the leguminous elevated the content and accumulation of N in inflorescences, comparatively to the single millet. In the plots without N-fertilizer and cultivated with sunnhemp the diameter of broccoli buds was similar to spontaneous vegetation + 150kg ha-1 of N. However, the yield of broccoli and the content and accumulation of N in buds were greater after spontaneous vegetation + 150kg ha-1 of N than after green manures without N-fertilizer. The utilization the N from biological fixation by broccoli inflorescences was 9.15% when single and 8.48% when intercropped.

  17. 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).

  18. Biological pretreatment of corn stover with white-rot fungus for enzymatic hydrolysis and bioethanol production

    Science.gov (United States)

    Pretreatment, as the first step towards conversion of lignocellulosic feedstocks to biofuels and/or chemicals remains one of the main barriers to commercial success. Typically, harsh methods are used to pretreat lignocellulosic biomass prior to its breakdown to sugars by enzymes, which also result ...

  19. Biological pretreatment of corn stover with white-rot fungus for improved enzymatic hydrolysis

    Science.gov (United States)

    Biological pretreatment of lignocellulosic biomass by white-rot fungus can represent a low-cost and eco-friendly alternative to harsh physical, chemical or physico-chemical pretreatment methods to facilitate enzymatic hydrolysis. However, fungal pretreatment can cause carbohydrate loss and it is, th...

  20. Slow and pressurized co-pyrolysis of coal and agricultural residues

    International Nuclear Information System (INIS)

    Aboyade, Akinwale O.; Carrier, Marion; Meyer, Edson L.; Knoetze, Hansie; Görgens, Johann F.

    2013-01-01

    Highlights: ► Evaluation of co-pyrolysis of coal and biomass in pressurized packed bed reactor. ► Relative influence of coal–biomass mix ratio, temperature and pressure also investigated. ► Results show significant synergy or chemical interactions in the vapor phase. ► Synergistic interactions did not influence distribution of lumped solid liquid and gas products. - Abstract: The distribution of products from the slow heating rate pyrolysis of coal, corn residues (cobs and stover), sugarcane bagasse and their blends were investigated by slow pressurized pyrolysis in a packed bed reactor. A factorial experimental design was implemented to establish the relative significance of coal–biomass mix ratio, temperature and pressure on product distribution. Results showed that the yield and composition of tar and other volatile products were mostly influenced by mix ratio, while temperature and pressure had a low to negligible significance under the range of conditions investigated. Analysis of the composition of condensates and gas products obtained showed that there was significant synergy or chemical interactions in the vapor phase during co-pyrolysis of coal and biomass. However, the interactions did not significantly affect the relative distribution of the lumped solid, liquid and gas products obtained from the blends, beyond what would be expected assuming additive behavior from the contributing fuels.

  1. Crop residues as raw materials for biorefinery systems - A LCA case study

    International Nuclear Information System (INIS)

    Cherubini, Francesco; Ulgiati, Sergio

    2010-01-01

    Our strong dependence on fossil fuels results from the intensive use and consumption of petroleum derivatives which, combined with diminishing oil resources, causes environmental and political concerns. The utilization of agricultural residues as raw materials in a biorefinery is a promising alternative to fossil resources for production of energy carriers and chemicals, thus mitigating climate change and enhancing energy security. This paper focuses on a biorefinery concept which produces bioethanol, bioenergy and biochemicals from two types of agricultural residues, corn stover and wheat straw. These biorefinery systems are investigated using a Life Cycle Assessment (LCA) approach, which takes into account all the input and output flows occurring along the production chain. This approach can be applied to almost all the other patterns that convert lignocellulosic residues into bioenergy and biochemicals. The analysis elaborates on land use change aspects, i.e. the effects of crop residue removal (like decrease in grain yields, change in soil N 2 O emissions and decrease of soil organic carbon). The biorefinery systems are compared with the respective fossil reference systems producing the same amount of products/services from fossils instead of biomass. Since climate change mitigation and energy security are the two most important driving forces for biorefinery development, the assessment focuses on greenhouse gas (GHG) emissions and cumulative primary energy demand, but other environmental categories are evaluated as well. Results show that the use of crop residues in a biorefinery saves GHG emissions and reduces fossil energy demand. For instance, GHG emissions are reduced by about 50% and more than 80% of non-renewable energy is saved. Land use change effects have a strong influence in the final GHG balance (about 50%), and their uncertainty is discussed in a sensitivity analysis. Concerning the investigation of the other impact categories, biorefinery systems

  2. Influence of twin-screw extrusion on soluble arabinoxylans and corn fiber gum from corn fiber.

    Science.gov (United States)

    Singkhornart, Sasathorn; Lee, Seul Gi; Ryu, Gi Hyung

    2013-09-01

    The effect of feed moisture content and screw speed in the extrusion process with and without chemical pretreatment of corn fiber was investigated. Different chemical pretreatment methods (NaOH and H2 SO4 solution) were compared. The improvement of reducing sugar, soluble arabinoxylans (SAX) content and the yield of corn fiber gum was measured. A high reducing sugar content was obtained in the filtrate fraction from the extruded destarched corn fiber (EDCF) with H₂SO₄ pretreatment. Feed moisture content most effectively improved both reducing sugar and SAX content of filtrate. Increasing feed moisture content and screw speed resulted in a higher SAX content in the filtrate of the EDCF with NaOH pretreatment. The SAX content of the residual solid from the EDCF with NaOH pretreatment was higher compared to H₂SO₄ pretreated and unpretreated samples and significantly increased with decreasing feed moisture content. The screw speed did not have a major impact after enzyme hydrolysis. The yield of corn fiber gum was increased by 12% using NaOH pretreatment combined with extrusion process as compared to the destarched corn fiber. The results show the great potential of the extrusion process as an effective pretreatment for disruption the lignocelluloses of corn fiber, leading to conversion of cellulose to glucose and hemicelluloses to SAX and isolation of corn fiber gum. © 2013 Society of Chemical Industry.

  3. 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.

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

    African Journals Online (AJOL)

    STORAGESEVER

    2010-03-15

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

  5. Carbaryl residues in maize products

    International Nuclear Information System (INIS)

    Zayed, S.M.A.D.; Mansour, S.A.; Mostafa, I.Y.; Hassan, A.

    1976-01-01

    The 14 C-labelled insecticide carbaryl was synthesized from [1- 14 C]-1-naphthol at a specific activity of 3.18mCig -1 . Maize plants were treated with the labelled insecticide under simulated conditions of agricultural practice. Mature plants were harvested and studied for distribution of total residues in untreated grains as popularly roasted and consumed, and in the corn oil and corn germ products. Total residues found under these conditions in the respective products were 0.2, 0.1, 0.45 and 0.16ppm. (author)

  6. Crescimento radicular, extração de nutrientes e produção de grãos de genótipos de milho em diferentes quantidades de palha de aveia-preta em plantio direto Root growth, nutrient extraction and grain yield of corn genotypes under different amounts of black oat crop residues under no-tillage

    Directory of Open Access Journals (Sweden)

    João Carlos de Moraes Sá

    2010-08-01

    Full Text Available A manutenção da palha na superfície do solo atua principalmente na proteção contra o impacto das gotas de chuva, reduzindo a desagregação, o escorrimento superficial, o transporte de sedimentos e, consequentemente, a erosão. Essa proteção pode ter efeitos significativos nos atributos da planta de milho. O objetivo deste trabalho foi avaliar o efeito da quantidade de palha de aveia-preta em plantio direto no crescimento radicular, na extração de nutrientes e na produção de grãos de genótipos de milho. O experimento foi conduzido em um Latossolo Vermelho distrófico típico, em delineamento experimental de blocos ao acaso em parcelas subdivididas, com três repetições. A parcela principal foi representada pela quantidade de palha na superfície do solo (0, sem palha; 5,0; e 10,0 Mg ha-1, e a subparcela, constituída por 13 genótipos de milho. A quantidade de palha alterou significativamente o comprimento radicular e a altura de requeima. Todavia, a interação entre palha e genótipo alterou significativamente as variáveis estudadas. O sistema radicular das plantas de milho foi beneficiado por doses adicionais de palha tanto na camada superficial (0-20 cm como na subsuperficial (50-100 cm do solo. O aumento na quantidade de palha na superfície do solo resultou na maior extração total de N, P e K e não alterou a extração total dos elementos Ca, Mg e S pela planta de milho.Crop residues on the soil surface act mainly as protection against raindrop impact, reducing aggregate disruption, runoff, sediment transport and consequently, erosion. This protection can have significant effects on the corn plant characteristics. The objective of this study was to evaluate the effect of the amount of black oat residues on no-tillage root development, nutrient uptake and grain yield of corn genotypes. The experiment was conducted in an Oxisol, in a randomized block design in split plots with three replications. The main plot was

  7. FORAGES AND PASTURES SYMPOSIUM: Optimizing the use of fibrous residues in beef and dairy diets.

    Science.gov (United States)

    Watson, A K; MacDonald, J C; Erickson, G E; Kononoff, P J; Klopfenstein, T J

    2015-06-01

    Increased corn prices over the past decade have altered land use away from traditional forage in favor of corn. Accordingly, beef and dairy producers have had to adopt nontraditional forage resources into their production systems, many of which have become available as a result of increased corn production. Corn residues have become more available due to increases in corn hectares and yield. The individual plant components (i.e., husk, leaf, and stem) vary in fiber digestibility (NDF digestibility estimates = 40.5, 31.4, and 0.6% ± 0.8 for husk, leaf, and stalk, respectively). Stocking cattle to consume 3.6 kg forage/25.5 kg of grain allows cattle to graze selectively; selection of husks and leaves improves cattle performance. Byproducts of the wet and dry milling industries can be supplemented to calves grazing corn residues to provide protein and energy. Optimal gains were observed when these byproducts were supplemented at approximately 2.5 kg/d to 250-kg growing calves. Gestating beef cows do not require supplemental inputs when grazing corn residue, if stocked appropriately. Alkaline treatment of crop residues improves their feeding value. Concentrations of up to 20% harvested corn residue treated with calcium oxide can be included in finishing diets with an average of 1.3% reduction in G:F when diets contain 40% wet or modified distillers grains. Conversely, when untreated corn residues are included in similar finishing diets, G:F is reduced by 13.4%. Calcium oxide-treated residues included in beef growing diets increases DMI and ADG without significant improvements in G:F. Calcium oxide treatment of corn residues has been evaluated in dairy diets by replacing corn or corn silage with variable results. Efficient use of nontraditional fiber sources, such as corn milling byproducts and corn residue, are critical to the future viability of ruminant animal production.

  8. Efecto de la suplementación con residuos de destilería del maíz en el comportamiento de novillas en una asociación de gramínea y leucaena Effect of supplementation with corn distillery residues on the performance of heifers in an association of grass and leucaena

    Directory of Open Access Journals (Sweden)

    Tania Sánchez

    2010-09-01

    Full Text Available El objetivo del presente trabajo fue evaluar el efecto de la suplementación con residuos de destilería del maíz en el comportamiento de novillas, en una asociación de gramínea y leucaena. El estudio se realizó en un área de la Estación Experimental "Indio Hatuey", en el municipio de Perico, provincia de Matanzas, Cuba. La especie de pasto predominante fue Panicum maximum cv. Likoni y como leguminosa Leucaena leucocephala. Se estudiaron 18 novillas, distribuidas en un diseño completamente aleatorizado en tres grupos de seis animales; el grupo control no recibió suplementación (A y los otros dos grupos se suplementaron con residuos de destilería del maíz en un 10% (B y 20% (C de los requerimientos de proteína con relación al peso vivo. Se determinó la composición química, la disponibilidad de materia seca, la ganancia de peso vivo, la infestaci��n parasitaria y el hematocrito. Al analizar las ganancias diarias por tratamiento se encontraron diferencias significativas (PThe objective of this work was to evaluate the effect of supplementation with corn distillery residues on the performance of heifers in an association of grass and leucaena. The study was conducted in an area of the Experimental Station "Indio Hatuey" , Perico municipality, Matanzas province, Cuba. The prevailing pasture species was Panicum maximum cv. Likoni and as legume, Leucaena leucocephala. Eighteen heifers, distributed in a completely randomized design in three groups of six animals, were used; the control group did not receive supplementation (A, and the other two groups were supplemented with corn distillery residues in 10% (B and 20% (C of the protein requirements with regards to live weight. The chemical composition, dry matter availability, live weight gain, parasite infestation and hematocrit were determined. When analyzing the daily gain per treatments, significant differences (P<0,05 were found and the highest values were obtained in treatment C

  9. 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

  10. 40 CFR 180.431 - Clopyralid; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ....0 Milk 0.2 Mustard greens 5.0 Mustard, seed 3.0 Oat, forage 9.0 Oat, grain 3.0 Oat, groats/rolled... Brassica, head and stem, subgroup 5A 2.0 Bushberry subgroup 13-07B 0.50 Canola, meal 6.0 Canola, seed 3.0... 1.0 Corn, sweet, stover 10.0 Crambe, seed 3.0 Cranberry 4.0 Egg 0.1 Flax, meal 6.0 Flax, seed 3.0...

  11. 40 CFR 180.533 - Esfenvalerate; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... 7.0 Muskmelon 0.5 Mustard greens 5.0 Okra 0.5 Pea, dry, seed 0.25 Pea, succulent 0.5 Peanut 0.02... 1.0 Artichoke, globe 1.0 Bean, dry, seed 0.25 Bean, snap, succulent 1.0 Beet, sugar, roots 0.05 Beet... husks removed 0.1 Corn, sweet, stover 15.0 Cotton, undelinted seed 0.2 Cucumber 0.5 Egg 0.03 Eggplant 0...

  12. Rendimento do milho em diferentes condições físicas de solo e quantidade de resíduo na ausência ou na presença de irrigação Corn response in different physical conditions of soil and amount soil cover residues with or without irrigation

    Directory of Open Access Journals (Sweden)

    Osmar Conte

    2009-07-01

    Full Text Available Visando avaliar o efeito do tráfego de máquinas, da profundidade de atuação da haste sulcadora de adubo e da quantidade de resíduos presentes na superfície do solo sobre o desempenho do milho, com e sem irrigação, foi conduzido um experimento, em semeadura direta, sobre um Argissolo Vermelho Distrófico. O delineamento foi de blocos casualizados (DBC, com 36 parcelas, sendo 18 irrigadas e 18 sem irrigação. Os tratamentos consistiram de seis doses de resíduos de aveia preta consorciada com ervilhaca (0, 2, 4, 5, 6 e 8Mg ha-1, duas profundidades teóricas de atuação da haste sulcadora de adubo da semeadora (6 e 12cm e duas condições de tráfego de máquinas (trator e colhedora, sendo enquadrados numa análise trifatorial com três repetições. A semeadura do milho foi realizada em 10 de dezembro de 2005, com densidade de 62.000 sementes por hectare. A adubação usada foi de 400kg ha-1 da formulação NPK 5-20-20 e duas aplicações de nitrogênio, totalizando 180kg ha-1. Foram avaliados o rendimento de grãos, a população e a matéria seca de raízes. Tanto a população de plantas, quanto o rendimento de grãos do milho, foram influenciados pela presença ou não de irrigação. A profundidade de atuação das hastes sulcadoras não interferiu em nenhumas das variáveis avaliadas no milho. A condição de tráfego de rodado afetou a produtividade e a população de plantas.This study evaluates the effect of machine traffic, soil mobilization, soil cover by crop residues and water supply on corn under no tillage on a Paleudult. Machine traffic intensity, working depth of driller shank furrow opener for fertilizer deposition and amount of residues covering the soil surface, with and without irrigation, were evaluated. The experimental design used was split plot, with 36 plots being 18 with irrigation and 18 without irrigation. The treatments were quantities (0, 2, 4, 5, 6 and 8Mg ha-1 of black oats (Avena strigosa and vetch

  13. 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.

  14. Land-use change and greenhouse gas emissions from corn and cellulosic ethanol

    Science.gov (United States)

    2013-01-01

    Background The greenhouse gas (GHG) emissions that may accompany land-use change (LUC) from increased biofuel feedstock production are a source of debate in the discussion of drawbacks and advantages of biofuels. Estimates of LUC GHG emissions focus mainly on corn ethanol and vary widely. Increasing the understanding of LUC GHG impacts associated with both corn and cellulosic ethanol will inform the on-going debate concerning their magnitudes and sources of variability. Results In our study, we estimate LUC GHG emissions for ethanol from four feedstocks: corn, corn stover, switchgrass, and miscanthus. We use new computable general equilibrium (CGE) results for worldwide LUC. U.S. domestic carbon emission factors are from state-level modelling with a surrogate CENTURY model and U.S. Forest Service data. This paper investigates the effect of several key domestic lands carbon content modelling parameters on LUC GHG emissions. International carbon emission factors are from the Woods Hole Research Center. LUC GHG emissions are calculated from these LUCs and carbon content data with Argonne National Laboratory’s Carbon Calculator for Land Use Change from Biofuels Production (CCLUB) model. Our results indicate that miscanthus and corn ethanol have the lowest (−10 g CO2e/MJ) and highest (7.6 g CO2e/MJ) LUC GHG emissions under base case modelling assumptions. The results for corn ethanol are lower than corresponding results from previous studies. Switchgrass ethanol base case results (2.8 g CO2e/MJ) were the most influenced by assumptions regarding converted forestlands and the fate of carbon in harvested wood products. They are greater than miscanthus LUC GHG emissions because switchgrass is a lower-yielding crop. Finally, LUC GHG emissions for corn stover are essentially negligible and insensitive to changes in model assumptions. Conclusions This research provides new insight into the influence of key carbon content modelling variables on LUC GHG emissions

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  16. Well-to-wheels energy use and greenhouse gas emissions of ethanol from corn, sugarcane and cellulosic biomass for US use

    International Nuclear Information System (INIS)

    Wang, Michael; Han, Jeongwoo; Dunn, Jennifer B; Cai Hao; Elgowainy, Amgad

    2012-01-01

    Globally, bioethanol is the largest volume biofuel used in the transportation sector, with corn-based ethanol production occurring mostly in the US and sugarcane-based ethanol production occurring mostly in Brazil. Advances in technology and the resulting improved productivity in corn and sugarcane farming and ethanol conversion, together with biofuel policies, have contributed to the significant expansion of ethanol production in the past 20 years. These improvements have increased the energy and greenhouse gas (GHG) benefits of using bioethanol as opposed to using petroleum gasoline. This article presents results from our most recently updated simulations of energy use and GHG emissions that result from using bioethanol made from several feedstocks. The results were generated with the GREET (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) model. In particular, based on a consistent and systematic model platform, we estimate life-cycle energy consumption and GHG emissions from using ethanol produced from five feedstocks: corn, sugarcane, corn stover, switchgrass and miscanthus. We quantitatively address the impacts of a few critical factors that affect life-cycle GHG emissions from bioethanol. Even when the highly debated land use change GHG emissions are included, changing from corn to sugarcane and then to cellulosic biomass helps to significantly increase the reductions in energy use and GHG emissions from using bioethanol. Relative to petroleum gasoline, ethanol from corn, sugarcane, corn stover, switchgrass and miscanthus can reduce life-cycle GHG emissions by 19–48%, 40–62%, 90–103%, 77–97% and 101–115%, respectively. Similar trends have been found with regard to fossil energy benefits for the five bioethanol pathways. (letter)

  17. Well-to-wheels energy use and greenhouse gas emissions of ethanol from corn, sugarcane and cellulosic biomass for US use

    Science.gov (United States)

    Wang, Michael; Han, Jeongwoo; Dunn, Jennifer B.; Cai, Hao; Elgowainy, Amgad

    2012-12-01

    Globally, bioethanol is the largest volume biofuel used in the transportation sector, with corn-based ethanol production occurring mostly in the US and sugarcane-based ethanol production occurring mostly in Brazil. Advances in technology and the resulting improved productivity in corn and sugarcane farming and ethanol conversion, together with biofuel policies, have contributed to the significant expansion of ethanol production in the past 20 years. These improvements have increased the energy and greenhouse gas (GHG) benefits of using bioethanol as opposed to using petroleum gasoline. This article presents results from our most recently updated simulations of energy use and GHG emissions that result from using bioethanol made from several feedstocks. The results were generated with the GREET (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) model. In particular, based on a consistent and systematic model platform, we estimate life-cycle energy consumption and GHG emissions from using ethanol produced from five feedstocks: corn, sugarcane, corn stover, switchgrass and miscanthus. We quantitatively address the impacts of a few critical factors that affect life-cycle GHG emissions from bioethanol. Even when the highly debated land use change GHG emissions are included, changing from corn to sugarcane and then to cellulosic biomass helps to significantly increase the reductions in energy use and GHG emissions from using bioethanol. Relative to petroleum gasoline, ethanol from corn, sugarcane, corn stover, switchgrass and miscanthus can reduce life-cycle GHG emissions by 19-48%, 40-62%, 90-103%, 77-97% and 101-115%, respectively. Similar trends have been found with regard to fossil energy benefits for the five bioethanol pathways.

  18. [Change of Bt protein in soil after growing Bt corns and returning corn straws to soil and its effects on soil nutrients].

    Science.gov (United States)

    Zeng, Ping; Feng, Yuan-Jiao; Zhang, Wan-Chun; Zhang, Yan-Fei; Dong, Wen-Chao; Wang, Jian-Wu

    2014-07-01

    The spatiotemporal dynamics of Bt protein in soil and the change of soil nutrients in rhizosphere soil, root surface soil and soils at 0-20, 20-40 and 40-60 cm were measured in greenhouse experiments. Two Bt corns, 5422Bt1 and 5422CBCL, and their near isogenic non-Bt variety 5422 were grown for 90 days and the crop residues were retained to soil. Results showed that 1.59 and 2.78 ng x g(-1) Bt protein were detected in the rhizosphere soil with Bt corns 5422Bt1 and 5422CBCL immediately after harvest. However, there were only trace amounts of Bt protein (Bt corn treatments after 30, 60 and 90 days. When corn residues returned to soil, Bt protein declined rapidly within 3 days and only trace amounts of Bt protein were measured after 7 days. There were no sig- nificant differences in organic matter, available nutrient (alkaline hydrolytic N, available P, available K) or total nutrient (total N, total P, total K) in root surface soils and soils at 0-20 cm, 20-40 cm and 40-60 cm among the Bt and non-Bt corns after 90 days. Sixty days after returning crop residues of 5422Btl to soil, the contents of organic matter and total N increased and the content of available K reduced significantly in the 0-20 cm soil depth. There were no significant differences in any other parameter at the 0-20 cm depth, neither for any parameter in the 20-40 cm and 40-60 cm soil depths compared to those in the non-Bt corn 5422 treatment. There were no significant differences in soil nutrient contents in Bt corn 5422CBCL treatment compared to those in non-Bt corn 5422 treatment except that available phosphorus content was reduced in root surface soils, and total P content increased at the 0-20 cm soil depth after 90 days. When crop residues of Bt corn 5422 CBCL were returned to soil, only available P content in the 0-20 cm soil layer was evidently higher compared to the soil receiving crop residues of non-Bt corn 5422. Results suggested that Bt protein released from root and crop residues of Bt

  19. Framework to Delay Corn Rootworm Resistance

    Science.gov (United States)

    This proposed framework is intended to delay the corn rootworm pest becoming resistant to corn genetically engineered to produce Bt proteins, which kill corn rootworms but do not affect people or wildlife. It includes requirements on Bt corn manufacturers.

  20. Residual deposits (residual soil)

    International Nuclear Information System (INIS)

    Khasanov, A.Kh.

    1988-01-01

    Residual soil deposits is accumulation of new formate ore minerals on the earth surface, arise as a result of chemical decomposition of rocks. As is well known, at the hyper genes zone under the influence of different factors (water, carbonic acid, organic acids, oxygen, microorganism activity) passes chemical weathering of rocks. Residual soil deposits forming depends from complex of geologic and climatic factors and also from composition and physical and chemical properties of initial rocks

  1. 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.

  2. Characterization of Anatomical, Chemical, and Biodegradable Properties of Fibers from Corn, Wheat, and Rice Residues Caracterización de Propiedades Anatómicas, Químicas y de Biodegradación de Fibras Provenientes de Residuos de Maíz, Trigo y Arroz

    Directory of Open Access Journals (Sweden)

    Rose Marie Garay M

    2009-09-01

    Full Text Available Anatomical, chemical, and biodegradation properties of fibers from wheat (Triticum aestivum L., rice (Oryza sativa L., and corn (Zea mays L. plant residues and from rice hull were characterized to generate scientific and technical knowledge to support decision making regarding their use. The anatomical and chemical properties were determined following standard procedures. The degree of biodeterioration was analyzed from growth of white rot fungus Pleurotus ostreatus (Jaq. Quél. in 30 d under favorable conditions. Afterwards, weight loss was evaluated for each residue. Three replicates were used, plus a control of radiata pine (Pinus radiata D. Don woodchips. The greatest proportion of a-cellulose was found in residues of rice plants (45.1%, with a high amount of extractable (non-structural components, that confer organoleptic characteristics, followed by rice hull (22.78%, which is explained by the presence of silica in their cells. Ash content was higher in wheat residues, reaching up to 18.34%. Anatomical characteristics were studied to corroborate potential use in industrial processes. Fiber length and wall thickness were similar to those of latifoliate wood fibers, although possibly less resistant because of lower lignification. The largest weight loss was from rice plant (32%, followed by rice hull (27%, and corn plants (26.6%. The most resistant was wheat plant (15.8%. All these materials had greater weight losses than the control sample (3.8%. Thus, given their anatomical and chemical properties, the use of plant residue fibers in industrial processes is technically possible, though with concern about their biodegradability.Se caracterizaron las propiedades anatómicas, químicas y biodegradación de fibras de residuos de plantas de trigo (Triticum aestivum L., plantas de arroz (Oryza sativa L., plantas de maíz (Zea mays L., y cáscara de arroz, con el objetivo de generar información y tomar decisiones de uso con bases científicas y

  3. 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

  4. 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.

  5. Polymorphisms in O-methyltransferase genes are associated with stover cell wall digestibility in European maize (Zea mays L.)

    DEFF Research Database (Denmark)

    Brenner, Everton A; Zein, Imad; Chen, Yongsheng

    2010-01-01

    Background OMT (O-methyltransferase) genes are involved in lignin biosynthesis, which relates to stover cell wall digestibility. Reduced lignin content is an important determinant of both forage quality and ethanol conversion efficiency of maize stover. Results Variation in genomic sequences coding...

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

    International Nuclear Information System (INIS)

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

    2012-01-01

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

  7. Decomposição de resíduos vegetais em latossolo sob cultivo de milho e plantas de cobertura Decomposition of plant residues in latosol under corn crop and cover crops

    Directory of Open Access Journals (Sweden)

    Arminda Moreira de Carvalho

    2008-12-01

    .Soil degradation occurs as a consequence of intensive preparation associated with monocropping systems with deposition of residues that are rapidly decomposed. The objective of this study was to investigate the decomposition rates of different cover plants residues in Latosol (Oxisol under conventional and no-tillage systems. The cover plants (Crotalaria juncea, Canavalia brasiliensis, Cajanus cajan, Mucuna pruriens, Helianthus annuus, Pennisetum glaucum, Raphanus sativus and natural fallow, as a control were used in a succession with maize. The cover plants were cut when flowering reached approximately 50 % and remained on the soil until the sowing of the maize. In the conventional system, plant residues were incorporated in subplots with plough. Litter bags with 10 g of dry matter of each species were placed on the soil surface and covered with plant residues to determine the decomposition rate along the dry (60 and 90 days of incubation and wet seasons (180, 210 and 240 days of incubation under both systems. During soil preparation and herbicide application before the sowing of maize, the remaining bags were removed from the field and kept in cold storage (0 ºC. After the sowing of maize, these bags were returned to the respective subplots, either on the surface for the no-tillage treatment or buried at 10 cm depth when under the incorporation treatment. The lowest decomposition rates were found for residues of Cajanus cajan Pennisetum glaucum, Mucuna pruriens, and natural fallow. Incorporation of plant residues accelerated the decomposition time, when compared to no-tillage system, except for Raphanus sativus. Maize yield was highest after the rotation with Canavalia brasiliensis.

  8. 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)

  9. Field evidence for the exposure of ground beetles to Cry1Ab from transgenic corn.

    Science.gov (United States)

    Zwahlen, Claudia; Andow, David A

    2005-01-01

    Non-target organisms associated with the soil might be adversely affected by exposure to the CrylAb protein from Bacillus thuringiensis (Bt) in transgenic corn (Zea mays L.). To check for such exposure, we used ELISA to test for Cry1Ab in ground beetles collected live from fields with Bt corn residues and Bt corn (Bt/Bt), Bt corn residues and non-Bt crops (Bt/non-Bt), or non-Bt corn residues and non-Bt crops (non-Bt/non-Bt). In fields with Bt corn residues (Bt/Bt and Bt/non-Bt), Cry1Ab was present in all seven species of ground beetles examined (Agonum placidum, Bembidion rupicola, Clivina impressefrons, Cyclotrachelus iowensis, Harpalus pensylvanicus, Poecilus chalcites, and Poecilus lucublandus). For the two most abundant species, P. chalcites and P. lucublandus, the proportion of beetles with Cry1Ab was significantly higher in Bt/Bt fields (0.50-1.0) and Bt/non-Bt fields (0.41-0.50) than in non-Bt/non-Bt fields (0.0). This is the first field evidence that some ground beetle species are exposed to Cry1Ab. The implications of exposure on the performance of these non-target organisms are unclear.

  10. Metabolism and Residues of 2,4-Dichlorophenoxyacetic Acid in DAS-40278-9 Maize (Zea mays) Transformed with Aryloxyalkanoate Dioxygenase-1 Gene.

    Science.gov (United States)

    Zhou, Xiao; Rotondaro, Sandra L; Ma, Mingming; Rosser, Steve W; Olberding, Ed L; Wendelburg, Brian M; Adelfinskaya, Yelena A; Balcer, Jesse L; Blewett, T Craig; Clements, Bruce

    2016-10-12

    DAS-40278-9 maize, which is developed by Dow AgroSciences, has been genetically modified to express the aryloxyalkanoate dioxygenase-1 (AAD-1) protein and is tolerant to phenoxy auxin herbicides, such as 2,4-dichlorophenoxyacetic acid (2,4-D). To understand the metabolic route and residue distribution of 2,4-D in DAS-40278-9 maize, a metabolism study was conducted with 14 C-radiolabeled 2,4-D applied at the maximum seasonal rate. Plants were grown in boxes outdoors. Forage and mature grain, cobs, and stover were collected for analysis. The metabolism study showed that 2,4-D was metabolized to 2,4-dichlorophenol (2,4-DCP), which was then rapidly conjugated with glucose. Field-scale residue studies with 2,4-D applied at the maximum seasonal rate were conducted at 25 sites in the U.S. and Canada to measure the residues of 2,4-D and free and conjugated 2,4-DCP in mature forage, grain, and stover. Residues of 2,4-D were not detectable in the majority of the grain samples and averaged <1.0 and <1.5 μg/g in forage and stover, respectively. Free plus conjugated 2,4-DCP was not observed in grain and averaged <1.0 μg/g in forage and stover.

  11. Soil Moisture Dynamics under Corn, Soybean, and Perennial Kura Clover

    Science.gov (United States)

    Ochsner, T.; Venterea, R. T.

    2009-12-01

    Rising global food and energy consumption call for increased agricultural production, whereas rising concerns for environmental quality call for farming systems with more favorable environmental impacts. Improved understanding and management of plant-soil water interactions are central to meeting these twin challenges. The objective of this research was to compare the temporal dynamics of soil moisture under contrasting cropping systems suited for the Midwestern region of the United States. Precipitation, infiltration, drainage, evapotranspiration, soil water storage, and freeze/thaw processes were measured hourly for three years in field plots of continuous corn (Zea mays L.), corn/soybean [Glycine max (L.) Merr.] rotation, and perennial kura clover (Trifolium ambiguum M. Bieb.) in southeastern Minnesota. The evapotranspiration from the perennial clover most closely followed the temporal dynamics of precipitation, resulting in deep drainage which was reduced up to 50% relative to the annual crops. Soil moisture utilization also continued later into the fall under the clover than under the annual crops. In the annual cropping systems, crop sequence influenced the soil moisture dynamics. Soybean following corn and continuous corn exhibited evapotranspiration which was 80 mm less than and deep drainage which was 80 mm greater than that of corn following soybean. These differences occurred primarily during the spring and were associated with differences in early season plant growth between the systems. In the summer, soil moisture depletion was up to 30 mm greater under corn than soybean. Crop residue also played an important role in the soil moisture dynamics. Higher amounts of residue were associated with reduced soil freezing. This presentation will highlight key aspects of the soil moisture dynamics for these contrasting cropping systems across temporal scales ranging from hours to years. The links between soil moisture dynamics, crop yields, and nutrient leaching

  12. Acceleration of the Enzymatic Hydrolysis of Corn Stover and Sugar Cane Bagasse Celluloses by Low Intensity Uniform Ultrasound

    Science.gov (United States)

    The cost-competitive production of bio-ethanol and other biofuels is currently impeded, mostly by high cost and low efficiency of enzymatic hydrolysis of feedstock biomass and especially plant celluloses. Despite substantial reduction in the cost of production of cellulolytic enzymes in recent times...

  13. 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,...

  14. 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.

  15. The study on effect of zeolite on nitrogen use efficiency of corn by 15N-isotope dilution method

    International Nuclear Information System (INIS)

    Li Changhong; Li Huaxing; Zhang Xinming; Liu Yuanjin

    2002-01-01

    A pot experiment was carried out to study the effect of natural zeolite on nitrogen use efficiency of corn by using 15 N-isotope dilution method. The results showed that application of zeolite could improve the corn growth and enhance the biomass of the corn seedling. By using zeolite, nitrogen use efficiency (NUE) of corn was increased by 23.2%-33.1% as compared with no-zeolite treatment; and the residual nitrogen has no significant difference between zeolite treatment and no-zeolite treatment

  16. Chemical composition and effects of micronized corn bran on iron bioavailability in rats

    Directory of Open Access Journals (Sweden)

    Gilson Irineu de Oliveira Junior

    2014-09-01

    Full Text Available The degermination of corn grains by dry milling generates 5% of a fibrous residue. After segregation and micronization, corn bran becomes a potential source of dietary fiber consumption. However, its effect on iron bioavailability has not been reported in the literature. The objective of the present study was to determine the nutritional composition of corn bran and its effects on iron bioavailability using the hemoglobin depletion-repletion method in rats. The animals were divided into two groups: cellulose (control and corn bran (experimental. The bran had high content of total dietary fiber, especially the insoluble fraction, and low phytate content. Hemoglobin uptake did not differ between groups at the end of repletion period, and the iron relative bioavailability value of the corn bran diet was 104% in comparison to that of the control group. The product evaluated proved to be a potential source of dietary fiber and it showed no negative effects on iron bioavailability.

  17. The in vitro fermentation of maize stover as affected by faecal ...

    African Journals Online (AJOL)

    The effect of different inoculum sources, obtained from the faeces of ungulates, i.e. horses (H), wildebeest (WB) and zebra (ZB) and combinations of inoculum sources on the fermentation of maize stover (MS) was investigated. Combined sources (CS) were: (1) H+WB, (2) H+ZB, (3) WB+ZB and (4) H+WB+ZB. Fresh faecal ...

  18. Product evaluation : Dow Corning 888

    Science.gov (United States)

    1986-07-10

    This report contains a product evaluation of Dow Corning 888 joint sealant. Dow Corning 888 is a one-part silicone material that cures to a low modulus silicone rubber upon exposure to atmospheric moisture. Its uses include transverse and longitudina...

  19. Separation of Corn Fiber and Conversion to Fuels and Chemicals Phase II: Pilot-scale Operation

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, Charles; Beery, Kyle; Orth, Rick; Zacher, Alan

    2007-09-28

    The purpose of the Department of Energy (DOE)-supported corn fiber conversion project, “Separation of Corn Fiber and Conversion to Fuels and Chemicals Phase II: Pilot-scale Operation” is to develop and demonstrate an integrated, economical process for the separation of corn fiber into its principal components to produce higher value-added fuel (ethanol and biodiesel), nutraceuticals (phytosterols), chemicals (polyols), and animal feed (corn fiber molasses). This project has successfully demonstrated the corn fiber conversion process on the pilot scale, and ensured that the process will integrate well into existing ADM corn wet-mills. This process involves hydrolyzing the corn fiber to solubilize 50% of the corn fiber as oligosaccharides and soluble protein. The solubilized fiber is removed and the remaining fiber residue is solvent extracted to remove the corn fiber oil, which contains valuable phytosterols. The extracted oil is refined to separate the phytosterols and the remaining oil is converted to biodiesel. The de-oiled fiber is enzymatically hydrolyzed and remixed with the soluble oligosaccharides in a fermentation vessel where it is fermented by a recombinant yeast, which is capable of fermenting the glucose and xylose to produce ethanol. The fermentation broth is distilled to remove the ethanol. The stillage is centrifuged to separate the yeast cell mass from the soluble components. The yeast cell mass is sold as a high-protein yeast cream and the remaining sugars in the stillage can be purified to produce a feedstock for catalytic conversion of the sugars to polyols (mainly ethylene glycol and propylene glycol) if desirable. The remaining materials from the purification step and any materials remaining after catalytic conversion are concentrated and sold as a corn fiber molasses. Additional high-value products are being investigated for the use of the corn fiber as a dietary fiber sources.

  20. 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

  1. Screening for corn rootworm (Coleoptera: Chrysomelidae) resistance to transgenic Bt corn in North Dakota

    Science.gov (United States)

    Western (WCR), Diabrotica virgifera virgifera LeConte, and northern corn rootworms (NCR), D. barberi Smith & Lawrence, are major economic pests of corn in much of the U.S. Corn Belt. Western corn rootworm resistance to transgenic corn expressing Bt (Bacillus thuringiensis) endotoxins has been confi...

  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. Effects of Pyramided Bt Corn and Blended Refuges on Western Corn Rootworm and Northern Corn Rootworm (Coleoptera: Chrysomelidae).

    Science.gov (United States)

    Keweshan, Ryan S; Head, Graham P; Gassmann, Aaron J

    2015-04-01

    The western corn rootworm, Diabrotica virgifera virgifera LeConte, and the northern corn rootworm, Diabrotica barberi Smith & Lawrence (Coleoptera: Chrysomelidae), are major pests of corn (Zea mays L). Several transgenic corn events producing insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt) kill corn rootworm larvae and reduce injury to corn roots. However, planting of Bt corn imposes selection on rootworm populations to evolve Bt resistance. The refuge strategy and pyramiding of multiple Bt toxins can delay resistance to Bt crops. In this study, we assessed the impact of four treatments--1) non-Bt corn, 2) Cry3Bb1 corn, 3) corn pyramided with Cry3Bb1 and Cry34/35Ab1, and 4) pyramided corn with a blended refuge--on survival, time of adult emergence, and size of western and northern corn rootworm. All treatments with Bt corn led to significant reductions in the number of adults that emerged per plot. However, at one location, we identified Cry3Bb1-resistant western corn rootworm. In some cases Bt treatments reduced size of adults and delayed time of adult emergence, with effects most pronounced for pyramided corn. For both species, the number of adults that emerged from pyramided corn with a blended refuge was significantly lower than expected, based solely on emergence from pure stands of pyramided corn and non-Bt corn. The results of this study indicate that pyramided corn with a blended refuge substantially reduces survival of both western and northern corn rootworm, and as such, should be a useful tool within the context of a broader integrated pest management strategy. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Corning lightweight core fabrication technologies

    Science.gov (United States)

    VanBrocklin, Randy R.; Edwards, Mary J.; Hobbs, Thomas W.

    2003-12-01

    Fabrication of lightweight mirrors from low expansion glasses can be achieved using various core and faceplate lightweighting techniques. Lightweighting can be achieved using abrasive waterjet cutting, CNC milling and a new approach that Corning is developing to produce lightweight cores based on Corning's patented ceramic extrusion process. The selection of which lightweighting technology to use is dependent on customer design considerations of the lightweight mirror. These lightweighting techniques are reviewed and discussed, along with advantages and disadvantages of each technique. Corning will also introduce and discuss their new core lightweighting process.

  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. Risk and the Value of Bt Corn

    OpenAIRE

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

    2004-01-01

    A conceptual model is developed to evaluate the effect of Bt corn on risk. Results highlight the importance of distinguishing between marginal and aggregate risk effects and demonstrate that the effect of Bt corn on risk depends crucially on the price paid for the technology. Empirical results show that, depending on the price, Bt corn can be marginally risk increasing or decreasing and can either increase or decrease corn acreage. Also, depending on the price, Bt corn can provide a risk bene...

  7. 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.

  8. Corn in consortium with forages

    OpenAIRE

    Cássia Maria de Paula Garcia; Marcelo Andreotti; Marcelo Carvalho Minhoto Teixeira Filho; Keny Samejima Mascarenha Lopes; Ciniro Costa; Erikelly Aline Ribeiro de Santana

    2013-01-01

    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 c...

  9. Residuation theory

    CERN Document Server

    Blyth, T S; Sneddon, I N; Stark, M

    1972-01-01

    Residuation Theory aims to contribute to literature in the field of ordered algebraic structures, especially on the subject of residual mappings. The book is divided into three chapters. Chapter 1 focuses on ordered sets; directed sets; semilattices; lattices; and complete lattices. Chapter 2 tackles Baer rings; Baer semigroups; Foulis semigroups; residual mappings; the notion of involution; and Boolean algebras. Chapter 3 covers residuated groupoids and semigroups; group homomorphic and isotone homomorphic Boolean images of ordered semigroups; Dubreil-Jacotin and Brouwer semigroups; and loli

  10. Comparison of Chemical and Degradability Characteristics of Green Forage and Silage of Sorghums Varieties with Corn Using In vitro

    Directory of Open Access Journals (Sweden)

    A. Hedayatipour

    2012-10-01

    Full Text Available The chemical and fermentative parameters of three fresh forages and silages of sorghum including Sweet, Pegah and Speedfeed varieties were compared with corn using in vitro method, also degradability coefficients of forages and silages were determined by in situ method. Forages were planted in the same condition and harvested in soft dough stage, then ensilaged in four replicates for each time of 30, 60 and 90 days of preservation in mini silos. Buffering capacity in green Sweet sorghum was lower than corn and Speedfeed, and acid detergent fiber and water soluble carbohydrates respectively were significantly highest and lowest in fresh forage of Speedfeed sorghum. In time of 60 days, percent of acid detergent lignin of corn silage was lower than Sweet and Speedfeed sorghum silages; similarly, residual water soluble carbohydrate was lowest in corn silage. The lactate Concentration in corn and Pegah sorghums was higher than Sweet and Speedfeed silages. In corn and Sweet sorghum silages, Contents of acetic acid and ammonium nitrogen were highest and lowest, respectively. In nylon bag experiment, Degradation rate of corn and Pegah sorghum forages were significantly higher than Sweet and Speedfeed sorghums that cause to more effective degradability with passage rate of 0.08 in this forages. Also, the slowly degradation coefficient of corn silage was higher than sorghums silages. In conclusion, Speedfeed sorghum forage is not suitable for making silage in comparison others, and corn silage had more potential of degradability.

  11. On-farm treatment of straws and stovers with urea

    International Nuclear Information System (INIS)

    Smith, T.

    2002-01-01

    The nutritional value of cereal crop residues to ruminants is constrained by low N and high fibre contents. These constraints can be alleviated by treatment with alkali, the most suitable of which, for smallholder use, is urea. However, it has not widely been used in Africa. Whilst in some areas, cost and availability of urea will be a factor, it may also be that the flexibility of the technique is not appreciated. The scope for adaptation at each stage of the procedure is reviewed, showing that the farmer does have options to develop a system suitable for a range of conditions. (author)

  12. 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...

  13. A survey of fermentation products and bacterial communities in corn silage produced in a bunker silo in China.

    Science.gov (United States)

    Wang, Chao; Han, Hongyan; Gu, Xueying; Yu, Zhu; Nishino, Naoki

    2014-01-01

    To evaluate the current practice of corn silage management in China, samples of bunker-made silage were collected from 14 farms within a 500-km radius of Beijing for the analysis of fermentation products and bacterial communities. Mean values for dry matter (DM) content were as low as 250 g/kg in both corn stover (St) and whole crop corn (Wc) silages, and pH values averaged 4.48 and 3.73, respectively. Only three of the 14 silages exhibited a lactic-to-acetic acid ratio > 1.0, indicating that the presence of acetic acid was predominant in fermentation. Although 1,2-propanediol content was marginal in most cases ( 25 g/kg DM. In contrast, 3 St silages had large amounts (> 10 g/kg DM) of butyric acid, and two of the three butyrate silages also had high concentrations of 1-propanol. Denaturing gradient gel electrophoresis analysis demonstrated that the bacterial community appeared similar in 10 out of the 14 silage samples. Bands indicating Lactobacillus buchneri, L. acetotolerans and Acetobacter pasteurianus were found in both the St and Wc silages, accounting for the high acetic acid content found across silage samples. © 2013 Japanese Society of Animal Science.

  14. Comparison of the Carbon Budget, Evapotranspiration, and Albedo Effect between the Biofuel Crops Switchgrass and Corn

    Science.gov (United States)

    Eichelmann, E.; Wagner-Riddle, C.; Warland, J. S.; Deen, B.; Voroney, P.

    2015-12-01

    Switching from annual cropping systems to perennial crops like switchgrass (Panicum virgatum L.) for biofuel feedstock production will have implications on carbon and water cycling as well as biophysical parameters, such as surface albedo.We conducted eddy covariance measurements of carbon dioxide and water fluxes over a mature (>5 years) switchgrass field over three years (2012 to 2014) and a continuous corn field during the year 2014. Both fields were located in Southern Ontario, Canada. Results for carbon and water cycling were compared between the two crops for the year 2014. Differences in surface albedo between the two biofuel cropping systems were compared for the years 2012, 2013, and 2014. In 2014 switchgrass was a carbon sink with a net ecosystem carbon balance (NECB) of -66±59 g C m-2, while corn was a carbon source with an NECB of 328±30 g C m-2 for a scenario where corn grain only is harvested and 634±34 g C m-2 for a scenario where both grain and stover are harvested. Annual evapotranspiration in 2014 was higher for the corn field (608.7±12 mm) than for the switchgrass field (517.0±8 mm). Albedo measurements showed an average annual negative radiative forcing effect for the switchgrass field compared to corn. Differences in albedo were largest in spring and fall when radiative forcing values of -10.2 and -5.5 W m-2 were observed, respectively.Comparing carbon cycling results from previous years, the switchgrass field was a source of carbon in 2012 (NEBC 106±45 g C m-2), but a small sink of carbon in 2013 (NEBC -59±45) and 2014. On average over the three measurement years, the switchgrass field was carbon neutral.Qualitative analysis of the carbon budget, evapotranspiration, and albedo results from this study suggest that biofuel produced from switchgrass can have more climate benefits than biofuel from continuous corn. This study provides important data for improvement of Life Cycle Analysis of switchgrass biofuel.

  15. 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...

  16. Resistance to Bt corn by western corn rootworm (Coleoptera: Chrysomelidae) in the U.S. corn belt

    Science.gov (United States)

    Transgenic Bt corn hybrids that produce insecticidal proteins from the bacterium Bacillus thuringiensis Berliner have become the standard insect management tactic across the United States Corn Belt. Widespread planting of Bt corn creates intense selection pressure for target insects to develop resis...

  17. Field-based assessment of resistance to Bt Corn by Western Corn Rootworm (Coleoptera: Chrysomelidae)

    Science.gov (United States)

    Western corn rootworm, Diabrotica virgifera virgifera LeConte, is a serious pest of corn and is managed with Bt corn that produce insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt). Beginning in 2009, severe injury to Bt corn producing Cry3Bb1 was observed in some cornfields ...

  18. Corn earworm (Lepidoptera: Noctuidae) in northeastern field corn: infestation levels and the value of transgenic hybrids.

    Science.gov (United States)

    Bohnenblust, Eric; Breining, Jim; Fleischer, Shelby; Roth, Gregory; Tooker, John

    2013-06-01

    Corn earworm, Helicoverpa zea (Boddie), is a polyphagous noctuid pest of agricultural crops across the United States that is gaining attention as a pest of field corn. Before the introduction of transgenic insect-resistant hybrids, this pest was largely ignored in field corn, but now many Bacillus thuringiensis (Bt) corn hybrids have activity against corn earworm. However, the value of control in the northeastern United States is unclear because the risk posed by corn earworm to field corn has not been well characterized. To understand the threat from corn earworm and the value of Bt hybrids in field corn, we assessed corn earworm injury in Bt and non-Bt hybrids at 16 sites across four maturity zones throughout Pennsylvania in 2010, and 10 sites in 2011. We also used corn earworm captures from the PestWatch pheromone trapping network to relate moth activity to larval damage in field corn. Corn earworm damage was less than one kernel per ear at 21 of 26 sites over both years, and the percentage of ears damaged was generally Bt hybrids suppressed corn earworm damage relative to non-Bt hybrids, but we found no differences among Bt traits. Cumulative moth captures through July effectively predicted damage at the end of the season. Currently, the additional benefit of corn earworm control provided by Bt hybrids is typically less than US$4.00/ha in northeastern field corn.

  19. Understanding N timing in corn yield and fertilizer N recovery: An insight from an isotopic labeled-N determination.

    Science.gov (United States)

    Maciel de Oliveira, Silas; Almeida, Rodrigo Estevam Munhoz de; Ciampitti, Ignacio A; Pierozan Junior, Clovis; Lago, Bruno Cocco; Trivelin, Paulo Cesar Ocheuze; Favarin, José Laércio

    2018-01-01

    Early fertilizer nitrogen (N) application on cover crops or their residues during the off-season is a practice adopted in Brazil subtropical conditions under no-tillage corn (Zea mays L.) systems. However, the effect of early N application on yield, plant N content, and N recovery efficiency (NRE) for corn is not yet well documented. Five fertilizer N timings in an oat-corn system were evaluated in two studies utilizing an isotopic-labeled N determination, 15N isotope. The N fertilization timings were: (i) oat tillering, (ii) 15 days before corn planting time, over the oat residues, (iii) at corn planting time, (iv) in-season at the three-leaf growth stage (V3), and (v) in-season split application at V3 and six-leaf (V6) growth stages. Based on the statistical analysis, the N fertilization timings were separated into three groups: 1) N-OATS, designated to N applied at oat; 2) N-PLANT, referred to pre-plant and planting N applications; and 3) N-CORN, designated to in-season corn N applications. Corn yield was not affected by the N fertilization timing. However, the N-CORN N fertilization timings enhanced NRE by 17% and 35% and final N recovery system (plant plus soil) by 16% and 24% all relative to N-OATS and N-PLANT groups, respectively. Overall, N-OATS resulted in the largest N derived from fertilizer (NDFF) amount in the deeper soil layer, in overall a delta of 10 kg N ha-1 relative to the rest of the groups. Notwithstanding corn yield was not affected, early N fertilization under subtropical conditions is not a viable option since NRE was diminished and the non-recovery N increased relative to the in-season N applications.

  20. Residue processing

    Energy Technology Data Exchange (ETDEWEB)

    Gieg, W.; Rank, V.

    1942-10-15

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

  1. 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...

  2. 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.

  3. "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…

  4. 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...

  5. 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...

  6. A case study of agricultural residue availability and cost for a cellulosic ethanol conversion facility in the Henan province of China

    Energy Technology Data Exchange (ETDEWEB)

    Webb, Erin [ORNL; Wu, Yun [ORNL

    2012-05-01

    A preliminary analysis of the availability and cost of corn stover and wheat straw for the area surrounding a demonstration biorefinery in the Henan Province of China was performed as a case study of potential cooperative analyses of bioenergy feedstocks between researchers and industry in the US and China. Though limited in scope, the purpose of this analysis is to provide insight into some of the issues and challenges of estimating feedstock availability in China and how this relates to analyses of feedstocks in the U.S. Completing this analysis also highlighted the importance of improving communication between U.S. researchers and Chinese collaborators. Understanding the units and terms used in the data provided by Tianguan proved to be a significant challenge. This was further complicated by language barriers between collaborators in the U.S. and China. The Tianguan demonstration biorefinery has a current capacity of 3k tons (1 million gallons) of cellulosic ethanol per year with plans to scale up to 10k tons (3.34 million gallons) per year. Using data provided by Tianguan staff in summer of 2011, the costs and availability of corn stover and wheat straw were estimated. Currently, there are sufficient volumes of wheat straw and corn stover that are considered 'waste' and would likely be available for bioenergy in the 20-km (12-mile) region surrounding the demonstration biorefinery at a low cost. However, as the industry grows, competition for feedstock will grow and prices are likely to rise as producers demand additional compensation to fully recover costs.

  7. Utilisation of corn (Zea mays) bran and corn fiber in the production of food components.

    Science.gov (United States)

    Rose, Devin J; Inglett, George E; Liu, Sean X

    2010-04-30

    The milling of corn for the production of food constituents results in a number of low-value co-products. Two of the major co-products produced by this operation are corn bran and corn fiber, which currently have low commercial value. This review focuses on current and prospective research surrounding the utilization of corn fiber and corn bran in the production of potentially higher-value food components. Corn bran and corn fiber contain potentially useful components that may be harvested through physical, chemical or enzymatic means for the production of food ingredients or additives, including corn fiber oil, corn fiber gum, cellulosic fiber gels, xylo-oligosaccharides and ferulic acid. Components of corn bran and corn fiber may also be converted to food chemicals such as vanillin and xylitol. Commercialization of processes for the isolation or production of food products from corn bran or corn fiber has been met with numerous technical challenges, therefore further research that improves the production of these components from corn bran or corn fiber is needed.

  8. Utilizing protein-lean coproducts from corn containing recombinant pharmaceutical proteins for ethanol production.

    Science.gov (United States)

    Paraman, Ilankovan; Moeller, Lorena; Scott, M Paul; Wang, Kan; Glatz, Charles E; Johnson, Lawrence A

    2010-10-13

    Protein-lean fractions of corn (maize) containing recombinant (r) pharmaceutical proteins were evaluated as a potential feedstock to produce fuel ethanol. The levels of residual r-proteins in the coproduct, distillers dry grains with solubles (DDGS), were determined. Transgenic corn lines containing recombinant green fluorescence protein (r-GFP) and a recombinant subunit vaccine of Escherichia coli enterotoxin (r-LTB), primarily expressed in endosperm, and another two corn lines containing recombinant human collagen (r-CIα1) and r-GFP, primarily expressed in germ, were used as model systems. The kernels were either ground and used for fermentation or dry fractionated to recover germ-rich fractions prior to grinding for fermentation. The finished beers of whole ground kernels and r-protein-spent endosperm solids contained 127-139 and 138-155 g/L ethanol concentrations, respectively. The ethanol levels did not differ among transgenic and normal corn feedstocks, indicating the residual r-proteins did not negatively affect ethanol production. r-Protein extraction and germ removal also did not negatively affect fermentation of the remaining mass. Most r-proteins were inactivated during the mashing process used to prepare corn for fermentation. No functionally active r-GFP or r-LTB proteins were found after fermentation of the r-protein-spent solids; however, a small quantity of residual r-CIα1 was detected in DDGS, indicating that the safety of DDGS produced from transgenic grain for r-protein production needs to be evaluated for each event. Protease treatment during fermentation completely hydrolyzed the residual r-CIα1, and no residual r-proteins were detectable in DDGS.

  9. Dispersal behavior of neonate European corn borer (Lepidoptera: Crambidae) on Bt corn.

    Science.gov (United States)

    Razze, J M; Mason, C E

    2012-08-01

    European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae), has historically been a significant economically important insect pest of corn (Zea mays L.) in the United States and Canada. The development in the 1990s of genetically modified corn expressing genes derived from Bacillus thuringiensis (Bt) that encodes insecticidal crystalline (Cry) proteins has proven to be effective in controlling this insect as well as other corn pests. The purpose of this study was to assess the movement and dispersal behavior of neonate European corn borer on Bt corn. We examined differences in neonate European corn borer dispersal behavior for the first 4 h after eclosion in the field among a stacked pyramid (Cry1F X Cry1Ab X Cry34/35Ab1) Bt corn, a Cry1F Bt corn, and a non-Bt sweet corn; and in the laboratory among a Bt corn hybrid containing Cry1F, a hybrid containing Cry1Ab, a pyramid combining these two hybrids (Cry1F X Cry1Ab), and a non-Bt near isoline corn. In field experiments, we found that dispersal was significantly higher on Bt corn compared with sweet corn. In laboratory experiments, dispersal was significantly higher on Cry1Ab Bt corn and Cry1F X Cry1Ab Bt corn than on non-Bt near isoline corn. Results indicated that neonate dispersal may be significantly greater in Bt cornfields compared with non-Bt cornfields. The findings on dispersal behavior in this study will be useful in evaluating the efficacy of a blended seed refuge system for managing European corn borer resistance in Bt corn.

  10. Our Mother Corn. Teacher's Guide.

    Science.gov (United States)

    Mathers, Sherry; And Others

    Designed to accompany the preceding student text (which deals with the role of corn in the Seneca, Pawnee, and Hopi tribes), the teaching guide contains a suggested sequence of activities and needed supplementary information along with an indication of the student text they follow. Sections include: farming notes; basic needs activities; house…

  11. Ethanol production using Saccharomyces cerevisiae cells immobilised on corn stem ground tissue

    Directory of Open Access Journals (Sweden)

    Vučurović Vesna M.

    2009-01-01

    Full Text Available Cell immobilisation in alcoholic fermentation has been extensively studied during the past few decades because of its technical and economical advantages over those of free cell systems. A biocatalyst was prepared by immobilising a commercial Saccharomyces cerevisiae strain (baker yeast on corn stem ground tissue for use in alcoholic fermentation. For this purpose, the yeast cells were submitted to the batch tests 'in situ' adsorption onto pieces of the corn stem ground tissue. Cells immobilisation was analysed by optical microscopy. It was determined that the addition of the corn stem ground tissue led to an increase of the pH value, total dissolved salts content, and sugar content in fermentation medium. The addition of 5 and 10g of the corn stem ground tissue per liter of medium, increased ethanol yield, decreased amount of residual sugar and the cells immobilisation was effective. Corn stem is one of the abundant, available, inexpensive, stable, reusable, nontoxic celulosic biomaterial with high porosity, which facilitates the transmission of substrates and products between carrier and medium. The prepared immobilised biocatalyst showed higher fermentation activity than free cells. The results indicate that corn stem might be an interesting support for yeast cell immobilisation, and also a cheap alternative recourse of mineral components with possibility of application for improving ethanol productivities.

  12. Residual risk

    African Journals Online (AJOL)

    ing the residual risk of transmission of HIV by blood transfusion. An epidemiological approach assumed that all HIV infections detected serologically in first-time donors were pre-existing or prevalent infections, and that all infections detected in repeat blood donors were new or incident infections. During 1986 - 1987,0,012%.

  13. 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.

  14. 40 CFR 180.145 - Fluorine compounds; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ..., roasted bean, postharvest 20 Coconut, postharvest 40 Coffee, bean, green, postharvest 15 Corn, field... Lettuce, leaf 7 Loganberry 7 Melon 7 Nectarine 7 Peach 7 Pepper 7 Plum, prune, fresh 7 Pumpkin 7 Raspberry... established for residues of fluoride in or on the following commodities from the postharvest fumigation with...

  15. Opportunities in utilization of agricultural residues in bio-composite ...

    African Journals Online (AJOL)

    In this paper, corn stalk as an agricultural residue was mixed with oak wood fiber to produce medium density fiberboards (MDF). Urea formaldehyde resin was used as binder. Hygroscopic and mechanical properties were evaluated according to the commercial standards in MDF production. Partial substitution of wood fiber ...

  16. Planting of neonicotinoid-coated corn raises honey bee mortality and sets back colony development

    Directory of Open Access Journals (Sweden)

    Olivier Samson-Robert

    2017-08-01

    Full Text Available Worldwide occurrences of honey bee colony losses have raised concerns about bee health and the sustainability of pollination-dependent crops. While multiple causal factors have been identified, seed coating with insecticides of the neonicotinoid family has been the focus of much discussion and research. Nonetheless, few studies have investigated the impacts of these insecticides under field conditions or in commercial beekeeping operations. Given that corn-seed coating constitutes the largest single use of neonicotinoid, our study compared honey bee mortality from commercial apiaries located in two different agricultural settings, i.e. corn-dominated areas and corn-free environments, during the corn planting season. Data was collected in 2012 and 2013 from 26 bee yards. Dead honey bees from five hives in each apiary were counted and collected, and samples were analyzed using a multi-residue LC-MS/MS method. Long-term effects on colony development were simulated based on a honey bee population dynamic model. Mortality survey showed that colonies located in a corn-dominated area had daily mortality counts 3.51 times those of colonies from corn crop-free sites. Chemical analyses revealed that honey bees were exposed to various agricultural pesticides during the corn planting season, but were primarily subjected to neonicotinoid compounds (54% of analysed samples contained clothianidin, and 31% contained both clothianidin and thiamethoxam. Performance development simulations performed on hive populations’ show that increased mortality during the corn planting season sets back colony development and bears contributions to collapse risk but, most of all, reduces the effectiveness and value of colonies for pollination services. Our results also have implications for the numerous large-scale and worldwide-cultivated crops that currently rely on pre-emptive use of neonicotinoid seed treatments.

  17. Pesticide residues in locally available cereals and vegetables

    International Nuclear Information System (INIS)

    Cunanan, S.A.; Santos, F.L.; Bonoan, L.S.

    1976-03-01

    Vegetable samples (pechay, cabbage, lettuce, green beans and tomatoes) bought from public markets in the Metro Manila area were analyzed for pesticide residues using gas chromatography. The samples analyzed in 1968-69 contained high levels of chlorinated pesticides such as DDT, Aldrin, Endrin, and Thiodan, while in the samples analyzed in January 1976, no chlorinated and organophosphate pesticides were detected. Cereal samples (rice, corn and sorghum) were obtained from the National Grains Authority and analyzed for pesticide residues and bromine residues. Total bromine residues was determined by neutron activation analysis. In most of the samples analyzed, the concentrations of pesticide residues were below the tolerance levels set by the FAO/WHO Committee on Pesticide Residues in Foods. An exception was one rice sample from Thailand, the bromine residue content (110ppm) of which exceeds the tolerance level of 50ppm

  18. 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…

  19. 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...

  20. Production and Partial Characterization of Alpha-Amylase from Corn ...

    African Journals Online (AJOL)

    Corn pomace, a by-product of corn from “ogi” production was used as a substrate for the production of alpha-amylase by a corn fermenting strain of Bacillus licheniformis ATCC 4527. The corn pomace was fortified with potassium phosphate, magnesium sulphate and 2% w/v glucose to produce corn pomace basal medium, ...

  1. Residual basins

    International Nuclear Information System (INIS)

    D'Elboux, C.V.; Paiva, I.B.

    1980-01-01

    Exploration for uranium carried out over a major portion of the Rio Grande do Sul Shield has revealed a number of small residual basins developed along glacially eroded channels of pre-Permian age. Mineralization of uranium occurs in two distinct sedimentary units. The lower unit consists of rhythmites overlain by a sequence of black shales, siltstones and coal seams, while the upper one is dominated by sandstones of probable fluvial origin. (Author) [pt

  2. Soil fertility and soil loss constraints on crop residue removal for energy production

    Energy Technology Data Exchange (ETDEWEB)

    Flaim, S.

    1979-07-01

    A summary of the methodologies used to estimate the soil fertility and soil loss constraints on crop residue removal for energy production is presented. Estimates of excess residue are developed for wheat in north-central Oklahoma and for corn and soybeans in central Iowa. These sample farming situations are analyzed in other research in the Analysis Division of the Solar Energy Research Institute.

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

    OpenAIRE

    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) technolog...

  4. 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.

  5. Impact of climate variability on N and C flux within the life cycle of biofuels produced from crop residues

    Science.gov (United States)

    Pourhashem, G.; Block, P. J.; Adler, P. R.; Spatari, S.

    2013-12-01

    Biofuels from agricultural feedstocks (lignocellulose) are under development to meet national policy objectives for producing domestic renewable fuels. Using crop residues such as corn stover as feedstock for biofuel production can minimize the risks associated with food market disruption; however, it demands managing residue removal to minimize soil carbon loss, erosion, and to ensure nutrient replacement. Emissions of nitrous oxide and changes to soil organic carbon (SOC) are subject to variability in time due to local climate conditions and cultivation practices. Our objective is to investigate the effect of climate inputs (precipitation and temperature) on biogeochemical greenhouse gas (GHG) emissions (N2O and SOC expressed as CO2) within the life cycle of biofuels produced from agricultural residues. Specifically, we investigate the impact of local climate variability on soil carbon and nitrogen fluxes over a 20-year biorefinery lifetime where biomass residue is used for lignocellulosic ethanol production. We investigate two cases studied previously (Pourhashem et al, 2013) where the fermentable sugars in the agricultural residue are converted to ethanol (biofuel) and the lignin byproduct is used in one of two ways: 1) power co-generation; or 2) application to land as a carbon/nutrient-rich amendment to soil. In the second case SOC losses are mitigated through returning the lignin component to land while the need for fertilizer addition is also eliminated, however in both cases N2O and SOC are subject to variability due to variable climate conditions. We used the biogeochemical model DayCent to predict soil carbon and nitrogen fluxes considering soil characteristics, tillage practices and local climate (e.g. temperature and rainfall). We address the impact of climate variability on the soil carbon and nitrogen fluxes by implementing a statistical bootstrap resampling method based on a historic data set (1980 to 2000). The ensuing probabilistic outputs from the

  6. Microclimate effects of crop residues on biological processes

    Science.gov (United States)

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

    1996-03-01

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

  7. High-conversion hydrolysates and corn sweetener production in dry-grind corn process.

    Science.gov (United States)

    Most corn is processed to fuel ethanol and distillers’ grain animal feed using the dry grind process. However, wet milling is needed to refine corn starch. Corn starch is in turn processed to numerous products, including glucose and syrup. However, wet milling is a capital, labor, and energy intensi...

  8. FARMER DEMAND FOR CORN ROOTWORM BT CORN: DO INSECT RESISTANCE MANAGEMENT GUIDELINES MATTER?

    OpenAIRE

    Langrock, Ines; Hurley, Terrance M.; Ostlie, Kenneth

    2003-01-01

    Farmer adoption of Bt corn and compliance with insect resistance management (IRM) regulations will influence the success of these regulations. The purpose of this paper is to use farmer survey data to estimate the demand for new corn rootworm Bt corn and the cost of complying with proposed IRM regulations.

  9. Improving the nutritive characteristics of corn flakes enriched with functional components

    Directory of Open Access Journals (Sweden)

    Košutić Milenko B.

    2017-01-01

    Full Text Available This paper investigates the effects of simultaneous addition of sunflower (3, 6 or 9 g/100 g of sample and dry residue of wild oregano (0.5 or 1 g/100 g of sample on the essential amino acids pattern and antioxidant potential of flake products. The accepted experimental design plan was 34. Data point that Score and PDCAAS values in flake products increase with increasing share of sunflower. Maximum value of phenolic compounds and antioxidant activity were experienced of TPC 2.84 mg/g, DPPH 0.75 mg/ml, FRAP 1.57 mg/g with the product having maximum shares of sunflower and dry residue of wild oregano. Tukey’s HSD test showed statistically significant differences between most of the mean values of amino acids content and antioxidant activity in the observed corn flakes. The response surface method has been applied for evaluation of amino acid content and antioxidative potential of corn flakes. Sunflower in flake products positively contributed to the protein nutritive value and dry residues of wild oregano elevated antioxidant potential of flake products and also contributed to the food waste valorisation in the food industry. Corn flakes are new products with improved essential amino acid pattern, antioxidant activity and functional properties due to added dry residue of wild oregano and sunflower. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III 46005 and Grant no. TR 31027

  10. Nitrous oxide and carbon dioxide emissions from monoculture and rotational cropping of corn, soybean and winter wheat

    International Nuclear Information System (INIS)

    Drury, C.F.; Yang, X.M.; Reynolds, W.D.; McLaughlin, N.B.

    2008-01-01

    Nitrous oxide (N 2 O) and carbon dioxide (CO 2 ) emissions from agricultural soils are influenced by different types of crops, the amounts and types of nitrogen fertilizers used, and the soil and climatic conditions under which the crops are grown. Crop rotation also has an impact on N 2 O emissions, as the crop residues used to supply soluble carbon to soil biota often differ from the crops being grown. This study compared the influence of crops and residues from preceding crops on N 2 O and CO 2 emissions from monoculture crops of soybeans, corn, and winter wheat at a site in Ontario. The phases of different rotations were compared with 2- and 3-year crop rotations. Results of the study showed that N 2 O emissions were approximately 3.1 to 5.1 times higher in monoculture corn than levels observed in winter wheat or soybean crops. When corn followed corn, average N 2 O emissions twice as high as when corn followed soybeans, and 65 per cent higher than when corn followed winter wheat. The higher levels of both N 2 O and CO 2 were attributed to higher inorganic nitrogen (N) application rates in corn crops. In the corn phase, CO 2 levels were higher when the preceding crop was winter wheat. It was concluded that N 2 O and CO 2 emissions from agricultural fields are influenced by both current and preceding crops, a fact which should be considered and accounted for in estimates and forecasts of agricultural greenhouse gas (GHG) emissions. 21 refs., 3 tabs., 10 figs

  11. Digestibility of amino acids in corn, corn coproducts, and bakery meal fed to growing pigs.

    Science.gov (United States)

    Almeida, F N; Petersen, G I; Stein, H H

    2011-12-01

    The objectives of this experiment were to determine the apparent ileal digestibility and the standardized ileal digestibility (SID) of CP and AA in bakery meal, corn gluten meal, corn gluten feed, corn germ meal, and hominy feed and to compare these values with the apparent ileal digestibility and SID of CP and AA in corn and distillers dried grains with solubles (DDGS). Eight growing barrows (initial BW: 82.5 ± 5.5 kg) were randomly allotted to an 8 × 8 Latin square design with 8 diets and 8 periods. Diets contained corn, DDGS, bakery meal, corn gluten meal, corn gluten feed, corn germ meal, or hominy feed as the sole source of protein and AA. An N-free diet was used to measure basal endogenous losses of AA and protein. Pigs were fed experimental diets for eight 7-d periods, with ileal digesta being collected on d 6 and 7 of each period. Results indicated that the SID of Lys in corn gluten meal (78.7%) was greater (P bakery meal, corn germ meal, and hominy feed (46.0, 48.4, 68.4, and 58.8%, respectively). The SID of all indispensable AA except Arg, Leu, and Met in bakery meal were not different from those in DDGS. The SID of Arg, His, Leu, and Met in corn gluten feed were less (P bakery meal had SID values of most AA that were less than in corn, but corn gluten meal had SID values for most AA that were greater than the SID of AA in corn, bakery meal, and corn coproducts.

  12. RESIDUAL RISK ASSESSMENTS - RESIDUAL RISK ...

    Science.gov (United States)

    This source category previously subjected to a technology-based standard will be examined to determine if health or ecological risks are significant enough to warrant further regulation for Coke Ovens. These assesments utilize existing models and data bases to examine the multi-media and multi-pollutant impacts of air toxics emissions on human health and the environment. Details on the assessment process and methodologies can be found in EPA's Residual Risk Report to Congress issued in March of 1999 (see web site). To assess the health risks imposed by air toxics emissions from Coke Ovens to determine if control technology standards previously established are adequately protecting public health.

  13. Watershed regressions for pesticides (warp) models for predicting atrazine concentrations in Corn Belt streams

    Science.gov (United States)

    Stone, Wesley W.; Gilliom, Robert J.

    2012-01-01

    Watershed Regressions for Pesticides (WARP) models, previously developed for atrazine at the national scale, are improved for application to the United States (U.S.) Corn Belt region by developing region-specific models that include watershed characteristics that are influential in predicting atrazine concentration statistics within the Corn Belt. WARP models for the Corn Belt (WARP-CB) were developed for annual maximum moving-average (14-, 21-, 30-, 60-, and 90-day durations) and annual 95th-percentile atrazine concentrations in streams of the Corn Belt region. The WARP-CB models accounted for 53 to 62% of the variability in the various concentration statistics among the model-development sites. Model predictions were within a factor of 5 of the observed concentration statistic for over 90% of the model-development sites. The WARP-CB residuals and uncertainty are lower than those of the National WARP model for the same sites. Although atrazine-use intensity is the most important explanatory variable in the National WARP models, it is not a significant variable in the WARP-CB models. The WARP-CB models provide improved predictions for Corn Belt streams draining watersheds with atrazine-use intensities of 17 kg/km2 of watershed area or greater.

  14. Corn yield for silage and grains in different integrated crop-livestock systems

    Directory of Open Access Journals (Sweden)

    Laíse da Silveira Pontes

    Full Text Available Abstract In this study, the objective was to assess the influence of two doses of N (90 and 180 kg N ha-1, added to the winter pastures, two integrated crop-livestock systems (ICLS, with and without trees and five positions between the tree rows, on the corn (Zea mays L. quality and productivity, for silage and grain. Adopting the complete randomized block design, the treatments included three replicates. In 2006, following the 14 x 3 m spacing (currently with 158 trees ha-1 the trees were planted in 6 out of the 12 paddocks. While the corn was implemented during summer of 2013/2014, cattle grazing on the annual pasture was done during the prior winter, in both ICLS. Corn for silage was reaped at the R5 phenological stage, whereas for grains it was done at 176 days post seeding. For silage, the corn plants were grinded and then stocked in the experimental mini PVC silos. The silage varied slightly in quality along the positions between the tree rows. The differences observed between N levels in the dry matter, crude protein (CP and grain productivity are expressions of the residual effects of the winter fertilization. Silage quality was improved by the shade effect which minimized the acid detergent fiber and raised the CP, although it reduced the corn production for silage and grains by 52%. Some feasible techniques to reduce these losses are discussed.

  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. Phosphorus digestibility and concentration of digestible and metabolizable energy in corn, corn coproducts, and bakery meal fed to growing pigs.

    Science.gov (United States)

    Rojas, O J; Liu, Y; Stein, H H

    2013-11-01

    Two experiments were conducted to determine the standardized total tract digestibility (STTD) of P and the concentration of DE and ME in corn, hominy feed, bakery meal, distillers dried grains with solubles (DDGS), corn gluten meal, corn gluten feed, and corn germ meal fed to growing pigs. In Exp. 1, 84 barrows (initial BW: 13.7±2.3 kg) were placed in metabolism cages and allotted to 14 diets with 6 replicate pigs per diet in a randomized complete block design. Seven diets were formulated to contain corn, hominy feed, bakery meal, DDGS, corn gluten meal, corn gluten feed, or corn germ meal as the sole source of P. Seven additional diets were similar to the initial 7 diets with the exception that 600 units of microbial phytase was included in each diet. The STTD of P was greater (Pbakery meal, and corn germ meal, and the STTD of P was also greater (Pbakery meal than in corn and hominy feed. Addition of phytase increased (Pbakery meal, and corn germ meal but not in corn gluten meal, corn gluten feed, or DDGS. In Exp. 2, 56 barrows (initial BW: 14.6±2.2 kg) were placed in metabolism cages and allotted to 7 diets with 8 replicate pigs per diet in a randomized complete block design. A corn-based diet consisting of 97.5% corn and vitamins and minerals was formulated. Four additional diets were formulated by mixing corn and DDGS, corn gluten feed, corn gluten meal, or corn germ meal, and 2 diets were based on hominy feed or bakery meal. The concentration of ME was 3,891, 3,675, 3,655, 3,694, 4,400, 3,169, and 3,150 kcal/kg DM in corn, hominy feed, bakery meal, DDGS, corn gluten meal, corn gluten feed, and corn germ meal, respectively. The ME (DM basis) in corn was greater (Pbakery meal, corn gluten feed, and corn germ meal, but less (Pbakery meal, and DDGS was greater (Pbakery meal, and corn germ meal, but phytase can be included in diets containing corn, hominy feed, bakery meal, and corn germ meal to improve P digestibility. The ME in corn gluten meal is greater than

  18. 40 CFR 174.517 - Bacillus thuringiensis Cry9C protein in corn; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus thuringiensis Cry9C protein... PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.517 Bacillus thuringiensis... Bacillus thuringiensis Cry9C protein in corn is exempted from the requirement of a tolerance for residues...

  19. 40 CFR 174.520 - Bacillus thuringiensis Cry1F protein in corn; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bacillus thuringiensis Cry1F protein... PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.520 Bacillus thuringiensis Cry1F protein in corn; exemption from the requirement of a tolerance. Residues of Bacillus thuringiensis...

  20. Residual nilpotence and residual solubility of groups

    International Nuclear Information System (INIS)

    Mikhailov, R V

    2005-01-01

    The properties of the residual nilpotence and the residual solubility of groups are studied. The main objects under investigation are the class of residually nilpotent groups such that each central extension of these groups is also residually nilpotent and the class of residually soluble groups such that each Abelian extension of these groups is residually soluble. Various examples of groups not belonging to these classes are constructed by homological methods and methods of the theory of modules over group rings. Several applications of the theory under consideration are presented and problems concerning the residual nilpotence of one-relator groups are considered.

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

    Directory of Open Access Journals (Sweden)

    Amit Kumar

    2016-06-01

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

  2. Nutrient addition to corn masa flour: effect on corn flour stability, nutrient loss, and acceptability of fortified corn tortillas.

    Science.gov (United States)

    Rosado, Jorge L; Cassís, Lorena; Solano, Lourdes; Duarte-Vázquez, Miguel A

    2005-09-01

    Iron, zinc, and vitamin B complex are among the most prevalent nutritional deficiencies in Mexico, with iron deficiency being the leading cause of anemia. Mexico has the highest per capita consumption of corn in the world, consumed mainly as tortilla. Thus, corn flour for making tortillas has been suggested as an effective strategy to overcome malnutrition in developing countries such as Mexico where corn is a staple food. The stability of micronutrients added to food is an important factor for the success of fortification programs. The aim of this study was to evaluate the stability of corn flour fortified with micronutrients, and to measure the effect of micronutrient fortification on the sensory quality and stability of the fortificants in fresh and stored tortilla. A commercially homogenized nonfortified corn flour (NCFC) produced from degermed white corn was fortified with a premix containing iron, zinc, thiamin, and riboflavin. Changes in thiamin, riboflavin, iron, and zinc content in fortified corn flour (FCF) and nonfortified corn flour (NFCF) during storage were investigated. Vitamin B1 and B2 content was determined by fluorescence spectroscopy while iron and zinc content was analyzed by atomic absorption. Thiamin content in FCF and NFCF showed a significant (p flour into tortillas. Storage time slightly affected the stability of riboflavin and thiamin in FCF while the cooking process produced considerable losses of both vitamins. Tortillas made from FCF were well accepted by Mexican adults. We conclude that the addition of vitamins and minerals in the forms and quantities used in this study do not modify the shelf-life of corn flour, and neither do they cause sensorial changes in tortillas made from FCF.

  3. Localized search cues in corn roots for western corn rootworm (Coleoptera: Chrysomelidae) larvae.

    Science.gov (United States)

    Bernklau, E J; Bjostad, L B; Meihls, L N; Coudron, T A; Lim, E; Hibbard, B E

    2009-04-01

    Cues that elicit a characteristic localized search behavior by neonate larvae of the western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), were extracted from living corn, Zea mays L., roots with acetone. Larvae were exposed to corn roots or to an acetone extract of corn roots and then transferred into a bioassay arena where their movements were tracked and recorded. After a 5-min exposure to live corn roots, larvae produced highly convoluted tracks that were indicative of a localized search behavior, and these distinctive tracks were also produced by larvae exposed to an acetone extract of corn roots. Larvae exposed to a filter paper control moved in relatively straight paths that were indicative of ranging behavior. Larval tracks were recorded by means of a videocamera and tracking software, and four parameters of movement were used to quantify the tracks: mean turn angle, mean meander, total distance, and maximum distance from origin. For every parameter measured, tracks resulting from exposure to the control were significantly different from tracks resulting from exposure to live corn roots and to all doses of the corn root extract. In a separate experiment, larvae exposed to corn root pieces or corn root juice exhibited the localized search behavior, but larvae exposed to oat root pieces and oat root juice (nonhost) exhibited ranging behavior.

  4. Insecticide enhancement with feeding stimulants in corn for western corn rootworm larvae (Coleoptera: Chrysomelidae).

    Science.gov (United States)

    Bernklau, E J; Bjostad, L B

    2005-08-01

    Amounts of the insecticide thiamethoxam required for 50% mortality of western corn rootworm larvae, Diabrotica virgifera virgifera LeConte, were reduced 100-fold when extracts of germinating corn, Zea mays L., were used to entice neonate larvae to feed on it. In behavioral bioassays, neonate rootworm larvae fed vigorously on filter paper disks treated with liquid pressed from corn roots. Moreover, disks treated with an acetone extract of corn (dried and rewetted with water) also elicited strong feeding from larvae. Larvae wandered away from filter paper disks treated with distilled water without feeding. Dilutions of thiamethoxam were tested in the bioassay alone or with corn extract and the efficacy of this insecticide was improved by the addition of the corn extract. For solutions containing 10 ppm thiamethoxam, 95% larval mortality occurred after 30 min of exposure when corn extract was present, but only 38% mortality occurred when the same concentration of insecticide alone (no feeding stimulants) was tested. Larval mortality after 24 h was significantly higher for corn extract-treated disks with 0.01, 0.1, 1, or 10 ppm insecticide than for the same concentrations without corn extract. Thiamethoxam did not deter larval feeding on corn extract, even at the highest concentration of thiamethoxam tested.

  5. Production of thermotolerant entomopathogenic Isaria fumosorosea SFP-198 conidia in corn-corn oil mixture.

    Science.gov (United States)

    Kim, Jae Su; Je, Yeon Ho; Roh, Jong Yul

    2010-04-01

    Low thermotolerance of entomopathogenic fungi is a major impediment to long-term storage and effective application of these biopesticides under seasonal high temperatures. The effects of high temperatures on the viability of an entomopathogenic fungus, Isaria fumosorosea SFP-198 (KCTC 0499BP), produced on different substrates amended with various additives were explored. Ground corn was found to be superior in producing the most thermotolerant conidia compared to yellow soybean, red kidney bean, and rice in a polyethylene bag production system. Using ground corn mixed with corn oil as a substrate resulted in only 7% reduction in germination compared to ground corn alone (67% reduction) after exposure of conidia to 50 degrees C for 2 h. Corn oil as an additive for ground corn was followed by inorganic salts (KCl and NaCl), carbohydrates (sucrose and dextrin), a sugar alcohol (sorbitol), and plant oils (soybean oil and cotton seed oil) in ability to improve conidial thermotolerance. Unsaturated fatty acids, such as linoleic acid and oleic acid, the main components of corn oil, served as effective additives for conidial thermotolerance in a dosage-dependent manner, possibly explaining the improvement by corn oil. This finding suggests that the corn-corn oil mixture can be used to produce highly thermotolerant SFP-198 conidia and provides the relation of unsaturated fatty acids as substrates with conidial thermotolerance.

  6. 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...

  7. 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 ...

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

    African Journals Online (AJOL)

    STORAGESEVER

    2008-11-19

    Nov 19, 2008 ... quality of corn (Zea mays indendata) mixed with legumes such as various cowpea (Vigna ungiuculata) and bean (Phaseolus vulgaris) ... seeding of soybean with corn in alternate-rows as 1 corn + 1 soybean or 1 corn + 2 ..... And also silage quality is many times more significant property than quantity.

  9. Energy yield for the production of ethanol from corn

    International Nuclear Information System (INIS)

    Chavanne, X.; Frangi, J.P.

    2008-01-01

    This article establishes the primary energy balance for making ethanol out of corn in the USA, calculated from the farm to the fuel station, following a methodology described in Chavanne and Frangi (C. R. Geoscience 339 (2007) 519-535). Raw data (direct energy and material consumption as well as their heat value and external costs) come from published papers related to this topic, technical textbooks, as well as reports from the US Departments of Agriculture and Energy. For the 2001 harvest, over the area producing more than 90% of ethanol and for the 2005 network of working refineries, 100 J of ethanol and recovery of by-products (the energy saved by the replacement of animal feed by these by-products is around 12% of the ethanol heat value) needed 86 ± 3 J of energy spending, of which more than 50 J is natural gas and 62 J is used in refineries. A third of the area of Nebraska corn must be irrigated with water pumped from underground, at an added cost of 26 ± 3 J. In 1996, the extra drying required, because of heavy rains, added 6 J. By comparison, 100 J of gasoline cost less than 25 J to be produced out of crude oil. Complementary studies of resource availability are not performed here. The largest possible reduction in energy costs can be achieved at the refinery stage, by fermenting by-products, gas residues, (from 62 J to around 12 J). The article gives also an expression for the expenditure to enable comparison between different energy systems, including everything from biomass to transport. For the ethanol case, the average cost is 130 J for 100 J of corn grain heat. (authors)

  10. Forest residues in cattle feed

    Directory of Open Access Journals (Sweden)

    João Elzeário Castelo Branco Iapichini

    2012-12-01

    Full Text Available The ruminants are capable of converting low-quality food, when they are complementes with high-energy source. Through the use of regional agricultural residues is possible to conduct more economical production systems, since energetic foods have high cost in animal production. There is very abundant availability of residues in agroforestry activities worldwide, so that if a small fraction of them were used with appropriate technical criteria they could largely meet the needs of existing herds in the world and thus meet the demands of consumption of protein of animal origin. The Southwest Region of São Paulo State has large area occupied by reforestation and wide availability of non-timber forest residues, which may represent more concentrated energetic food for ruminant production. This experiment aimed to evaluate the acceptability of ground pine (20, 30 and 40%, replacing part of the energetic food (corn, present in the composition of the concentrate and was performed at the Experimental Station of Itapetininga - Forest Institute / SMA, in the dry season of 2011. It were used four crossbred steers, mean 18 months old, average body weight of 250 kg, housed in a paddock provided with water ad libitum and covered troughs for supplementation with the experimental diet. The adjustment period of the animals was of 07 days and the measurement of the levels of consumption, physiological changes, acceptability and physiological parameters were observed during the following 25 days. The concentrate supplement was formulated based on corn (76.2%, Soybean Meal (20%, urea (2%, Ammonium sulfate (0.4%, calcite (1.4%, Mineral Core (1% and finely ground Pine Cone, replacing corn. In preparing food, the formulas were prepared to make them isoproteic/energetic, containing the following nutrient levels: 22% Crude Protein (CP and 79% of Total Nutrients (TDN. The animals received the supplement in three steps for each level of cone replaced, being offered in the

  11. A kinetic approach to evaluate salinity effects on carbon mineralization in a plant residue-amended soil*

    Science.gov (United States)

    Nourbakhsh, Farshid; Sheikh-Hosseini, Ahmad R.

    2006-01-01

    The interaction of salinity stress and plant residue quality on C mineralization kinetics in soil is not well understood. A laboratory experiment was conducted to study the effects of salinity stress on C mineralization kinetics in a soil amended with alfalfa, wheat and corn residues. A factorial combination of two salinity levels (0.97 and 18.2 dS/m) and four levels of plant residues (control, alfalfa, wheat and corn) with three replications was performed. A first order kinetic model was used to describe the C mineralization and to calculate the potentially mineralizable C. The CO2-C evolved under non-saline condition, ranged from 814.6 to 4842.4 mg CO2-C/kg in control and alfalfa residue-amended soils, respectively. Salinization reduced the rates of CO2 evolution by 18.7%, 6.2% and 5.2% in alfalfa, wheat and corn residue-amended soils, respectively. Potentially mineralizable C (C 0) was reduced significantly in salinized alfalfa residue-treated soils whereas, no significant difference was observed for control treatments as well as wheat and corn residue-treated soils. We concluded that the response pattern of C mineralization to salinity stress depended on the plant residue quality and duration of incubation. PMID:16972320

  12. Gasoline, diesel, and ethanol biofuels from grasses and plants

    National Research Council Canada - National Science Library

    Gupta, Ram B; Demirbas, Ayhan

    2010-01-01

    ...-generation biofuels obtained from nonfood biomass, such as forest residue, agricultural residue, switchgrass, corn stover, waste wood, and municipal solid wastes. Various technologies are discussed, including cellulosic ethanol, biomass gasification, synthesis of diesel and gasoline, biocrude by hydrothermal liquefaction, bio-oil by fast pyrolysis, and the...

  13. Genetic variability in populations of sweet corn, common corn and teosinte

    OpenAIRE

    Almeida,Cicero; Amorim,Edson Perito; Barbosa Neto,José Fernandes; Cardoso Filho,Julio Alves; Sereno,Maria Jane Cruz de Melo

    2011-01-01

    The maize (Zea mays L. ssp. mays) has several related species, called teosinte, which are distributed in various subspecies of Zea and other genera. Among the different types of corn, sweet corn shows a great potential for human food. This type was originated from mutations, which increased the amount of polysaccharide in the endosperm. In Brazil there are populations of sweet corn, common maize and teosinte, however, little is known about their genetic variability. Hence, the aim of this pre...

  14. Genetic variability in populations of sweet corn, common corn and teosinte.

    OpenAIRE

    Cicero Almeida; Edson Perito Amorim; José Fernandes Barbosa Neto; Julio Alves Cardoso Filho; Maria Jane Cruz de Melo Sereno

    2011-01-01

    The maize (Zea mays L. ssp. mays) has several related species, called teosinte, which are distributed in varioussubspecies of Zea and other genera. Among the different types of corn, sweet corn shows a great potential for human food. This typewas originated from mutations, which increased the amount of polysaccharide in the endosperm. In Brazil there are populations ofsweet corn, common maize and teosinte, however, little is known about their genetic variability. Hence, the aim of this presen...

  15. 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 mos