The Experts below are selected from a list of 2676 Experts worldwide ranked by ideXlab platform
Felipe Alatristemondragon - One of the best experts on this subject based on the ideXlab platform.
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hydrogen production from acid and enzymatic Oat Straw hydrolysates in an anaerobic sequencing batch reactor performance and microbial population analysis
International Journal of Hydrogen Energy, 2013Co-Authors: Jorge Arreolavargas, Lourdes B. Celis, Elias Razoflores, German Buitron, Felipe AlatristemondragonAbstract:Abstract Feasibility of hydrogen production from acid and enzymatic Oat Straw hydrolysates was evaluated in an anaerobic sequencing batch reactor at 35 °C and constant substrate concentration (5 g chemical oxygen demand/L). In a first experiment, hydrogen production was replaced by methane production. Selective pressures applied in a second experiment successfully prevented methane production. During this experiment, initial feeding with glucose/xylose, as model substrates, promoted biomass granulation. Also, the highest hydrogen molar yield (HMY, 2 mol H 2 /mol sugar consumed) and hydrogen production rate (HPR, 278 mL H 2 /L-h) were obtained with these model substrates. Gradual substitution of glucose/xylose by acid hydrolysate led to disaggregation of granules and lower HPR and HMY. When the model substrates were completely substituted by enzymatic hydrolysate, the HMY and HPR were 0.81 mol H 2 /mol sugar consumed and 29.6 mL H 2 /L-h, respectively. Molecular analysis revealed a low bacterial diversity in the stages with high hydrogen production and vice versa. Furthermore, Clostridium pasteurianum was identified as the most abundant species in stages with a high hydrogen production. Despite that feasibility of hydrogen production from hydrolysates was demonstrated, lower performance from hydrolysates than from model substrates was obtained.
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chemical and enzymatic sequential pretreatment of Oat Straw for methane production
Bioresource Technology, 2012Co-Authors: Francisco Gomeztovar, Lourdes B. Celis, Elias Razoflores, Felipe AlatristemondragonAbstract:Oat Straw was subjected to sequential pretreatment: acid/alkaline/enzymatic, to convert the lignocellulosic material in soluble sugars. The hydrolysates from acid pretreatment (2% HCl, 90 °C) and enzymatic pretreatment (cellulase, pH 4.5, 45 °C) were used as substrates in two lab-scale UASB reactors for methane production. The acid and enzymatic hydrolysates contained 25.6 and 35.3g/L of total sugars, respectively, which corresponded to a COD of 23.6 and 30.5 g/L, respectively. The UASB reactor fed with acid hydrolysate achieved a maximum methane yield of 0.34 L CH(4)/g COD at an organic loading rate (OLR) of 2.5 g COD/L-d. In the reactor fed with enzymatic hydrolysate the methane yield was 0.36 LCH(4)/g COD at OLR higher than 8.8 g COD/L-d. The anaerobic digestion of both hydrolysates was feasible without the need of a detoxification step. The sequential pretreatment of Oat Straw allowed to solubilize 96.8% of hemicellulose, 77.2% of cellulose and 42.2% of lignin.
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continuous production of hydrogen from Oat Straw hydrolysate in a biotrickling filter
International Journal of Hydrogen Energy, 2011Co-Authors: Sonia Arriaga, Felipe Alatristemondragon, Izcoatl Rosas, Elias RazofloresAbstract:Abstract Hydrogen was produced in a biotrickling filter (BF) packed with perlite and fed with Oat Straw acid hydrolysate at 30 °C. Inlet chemical oxygen demand (COD) from 1.2 to 35 g/L and hydraulic retention time (HRT) between 24 h and 6 h were assayed. With increasing inlet COD or decreasing HRT, H 2 production rate (HPR) increased but H 2 production yield (HY) decreased. Maximum HPR of 81.4 mL H 2 /L reactor h (3.3 mmol H 2 /L reactor h) and HY of 2.9 mol H 2 /mol hexose consumed were found at an inlet COD of 0.05 g COD /L h (HRT 24 h) and 2.9 g COD /L h (HRT 12 h), respectively. Maximum hydrogen composition in gas was 45 ± 4% (v/v) with CO 2 as balance. Methane was not detected. Maximum HPR and inlet COD used in this work were higher than others reported for reactors with suspended or fixed biomass. However, implementation of strategies for biomass control to avoid reactor clogging is needed.
Curtis Miller - One of the best experts on this subject based on the ideXlab platform.
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biogas and ch4 productivity by co digesting swine manure with three crop residues as an external carbon source
Bioresource Technology, 2010Co-Authors: Xiao Wu, Curtis MillerAbstract:Abstract Co-digesting swine manure with three agricultural residues, i.e., corn stalks, Oat Straw, and wheat Straw, to enhance biogas productivity was investigated in this study. A 3 × 3 experimental design with duplicates was adopted (3 crop residues × 3 carbon/nitrogen ratios) to examine the improvement of batch digestion in terms of biogas volume produced, CH4 content in the biogas, and net CH4 volume. The crop residues were first cut into small sections and then ground into fine particles smaller than 40 mesh size (0.422 mm) before being added to digesters. All the digesters were run simultaneously under controlled temperature at 37 ± 0.1 °C. The length of experiment was 25 days. The results showed that all crop residues significantly increased biogas production and net CH4 volume at all C/N ratios, among which corn stalks performed the best with increase in daily maximum biogas volume by 11.4-fold as compared to the control, followed by Oat Straw (8.45-fold) and wheat Straw (6.12-fold) at the C/N ratio of 20/1, which was found to be the optimal C/N ratio for co-digestion in the present study. In addition, corn stalks achieved the highest CH4 content in the biogas (∼68%), which was about 11% higher than that of Oat Straw (∼57%), whereas wheat Straw and the control both had produced biogas with ∼47% CH4 content. Wheat Straw demonstrated a lower biogas productivity than corn stalks and Oat Straw even it had a higher carbon content (46%) than the latter two residues (39%).
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biogas and ch4 productivity by co digesting swine manure with three crop residues as an external carbon source
Bioresource Technology, 2010Co-Authors: Xiao Wu, Curtis MillerAbstract:Co-digesting swine manure with three agricultural residues, i.e., corn stalks, Oat Straw, and wheat Straw, to enhance biogas productivity was investigated in this study. A 3x3 experimental design with duplicates was adopted (3 crop residuesx3 carbon/nitrogen ratios) to examine the improvement of batch digestion in terms of biogas volume produced, CH(4) content in the biogas, and net CH(4) volume. The crop residues were first cut into small sections and then ground into fine particles smaller than 40 mesh size (0.422mm) before being added to digesters. All the digesters were run simultaneously under controlled temperature at 37+/-0.1 degrees C. The length of experiment was 25days. The results showed that all crop residues significantly increased biogas production and net CH(4) volume at all C/N ratios, among which corn stalks performed the best with increase in daily maximum biogas volume by 11.4-fold as compared to the control, followed by Oat Straw (8.45-fold) and wheat Straw (6.12-fold) at the C/N ratio of 20/1, which was found to be the optimal C/N ratio for co-digestion in the present study. In addition, corn stalks achieved the highest CH(4) content in the biogas ( approximately 68%), which was about 11% higher than that of Oat Straw ( approximately 57%), whereas wheat Straw and the control both had produced biogas with approximately 47% CH(4) content. Wheat Straw demonstrated a lower biogas productivity than corn stalks and Oat Straw even it had a higher carbon content (46%) than the latter two residues (39%).
Elias Razoflores - One of the best experts on this subject based on the ideXlab platform.
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hydrogen production from acid and enzymatic Oat Straw hydrolysates in an anaerobic sequencing batch reactor performance and microbial population analysis
International Journal of Hydrogen Energy, 2013Co-Authors: Jorge Arreolavargas, Lourdes B. Celis, Elias Razoflores, German Buitron, Felipe AlatristemondragonAbstract:Abstract Feasibility of hydrogen production from acid and enzymatic Oat Straw hydrolysates was evaluated in an anaerobic sequencing batch reactor at 35 °C and constant substrate concentration (5 g chemical oxygen demand/L). In a first experiment, hydrogen production was replaced by methane production. Selective pressures applied in a second experiment successfully prevented methane production. During this experiment, initial feeding with glucose/xylose, as model substrates, promoted biomass granulation. Also, the highest hydrogen molar yield (HMY, 2 mol H 2 /mol sugar consumed) and hydrogen production rate (HPR, 278 mL H 2 /L-h) were obtained with these model substrates. Gradual substitution of glucose/xylose by acid hydrolysate led to disaggregation of granules and lower HPR and HMY. When the model substrates were completely substituted by enzymatic hydrolysate, the HMY and HPR were 0.81 mol H 2 /mol sugar consumed and 29.6 mL H 2 /L-h, respectively. Molecular analysis revealed a low bacterial diversity in the stages with high hydrogen production and vice versa. Furthermore, Clostridium pasteurianum was identified as the most abundant species in stages with a high hydrogen production. Despite that feasibility of hydrogen production from hydrolysates was demonstrated, lower performance from hydrolysates than from model substrates was obtained.
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chemical and enzymatic sequential pretreatment of Oat Straw for methane production
Bioresource Technology, 2012Co-Authors: Francisco Gomeztovar, Lourdes B. Celis, Elias Razoflores, Felipe AlatristemondragonAbstract:Oat Straw was subjected to sequential pretreatment: acid/alkaline/enzymatic, to convert the lignocellulosic material in soluble sugars. The hydrolysates from acid pretreatment (2% HCl, 90 °C) and enzymatic pretreatment (cellulase, pH 4.5, 45 °C) were used as substrates in two lab-scale UASB reactors for methane production. The acid and enzymatic hydrolysates contained 25.6 and 35.3g/L of total sugars, respectively, which corresponded to a COD of 23.6 and 30.5 g/L, respectively. The UASB reactor fed with acid hydrolysate achieved a maximum methane yield of 0.34 L CH(4)/g COD at an organic loading rate (OLR) of 2.5 g COD/L-d. In the reactor fed with enzymatic hydrolysate the methane yield was 0.36 LCH(4)/g COD at OLR higher than 8.8 g COD/L-d. The anaerobic digestion of both hydrolysates was feasible without the need of a detoxification step. The sequential pretreatment of Oat Straw allowed to solubilize 96.8% of hemicellulose, 77.2% of cellulose and 42.2% of lignin.
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continuous production of hydrogen from Oat Straw hydrolysate in a biotrickling filter
International Journal of Hydrogen Energy, 2011Co-Authors: Sonia Arriaga, Felipe Alatristemondragon, Izcoatl Rosas, Elias RazofloresAbstract:Abstract Hydrogen was produced in a biotrickling filter (BF) packed with perlite and fed with Oat Straw acid hydrolysate at 30 °C. Inlet chemical oxygen demand (COD) from 1.2 to 35 g/L and hydraulic retention time (HRT) between 24 h and 6 h were assayed. With increasing inlet COD or decreasing HRT, H 2 production rate (HPR) increased but H 2 production yield (HY) decreased. Maximum HPR of 81.4 mL H 2 /L reactor h (3.3 mmol H 2 /L reactor h) and HY of 2.9 mol H 2 /mol hexose consumed were found at an inlet COD of 0.05 g COD /L h (HRT 24 h) and 2.9 g COD /L h (HRT 12 h), respectively. Maximum hydrogen composition in gas was 45 ± 4% (v/v) with CO 2 as balance. Methane was not detected. Maximum HPR and inlet COD used in this work were higher than others reported for reactors with suspended or fixed biomass. However, implementation of strategies for biomass control to avoid reactor clogging is needed.
Paulo Cesar Ferreira Linhares - One of the best experts on this subject based on the ideXlab platform.
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soil structural behavior as a function of the amount of coverage of maize and Oat Straw on oxisol on subtropical region
The Journal of Agricultural Science, 2019Co-Authors: Joaquim Odilon Pereira, V B Dantas, Suedemio De Lima Silva, Rafael Oliveira Batista, Roberto Vieira Pordeus, Marineide Jussara Diniz, Francisco De Assis De Oliveira, Paulo Cesar Ferreira LinharesAbstract:It is undeniable which soil management systems with intensive use of machines and with little formation of organic matter result in the deterioration of the soil structure. The relation among the values of organic matter in the soil profile as function of the quantity of residue left on the soil surface during the harvest has been little documented. This evaluation will be very important to provide and to apply the best optimization model of the soil management system. The objective of this work was to value the contribution of the mulch cover of maize and Oat Straw, applied in the soil surface at different quantities and of the soil textural porosity at the change of the soil structural porosity. The experiment was carried out from August to November 2005 on a Oxisol, with clay texture, located at the Experiment Farm of Agricultural Engineering from the UNIOESTE, Cascavel, Parana, Brazil (24°54′ S; 53°31′ W). The average soil texture in top 20 cm was 126, 195 and 679 g kg-1 of sand, silt and clay respectively. Aggregates sizes distribution, soil bulk density, particles density and textural density and soil organic matter were determined at the laboratory for evaluation of the soil structural parameters. For all conditions: application rates, and distribution in the layers of soil depth, the cover with Oat Straw produced more organic matter and presented a positive effect faster on the soil structural voids ratio than the coverage with maize Straw.
Xiao Wu - One of the best experts on this subject based on the ideXlab platform.
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biogas and ch4 productivity by co digesting swine manure with three crop residues as an external carbon source
Bioresource Technology, 2010Co-Authors: Xiao Wu, Curtis MillerAbstract:Abstract Co-digesting swine manure with three agricultural residues, i.e., corn stalks, Oat Straw, and wheat Straw, to enhance biogas productivity was investigated in this study. A 3 × 3 experimental design with duplicates was adopted (3 crop residues × 3 carbon/nitrogen ratios) to examine the improvement of batch digestion in terms of biogas volume produced, CH4 content in the biogas, and net CH4 volume. The crop residues were first cut into small sections and then ground into fine particles smaller than 40 mesh size (0.422 mm) before being added to digesters. All the digesters were run simultaneously under controlled temperature at 37 ± 0.1 °C. The length of experiment was 25 days. The results showed that all crop residues significantly increased biogas production and net CH4 volume at all C/N ratios, among which corn stalks performed the best with increase in daily maximum biogas volume by 11.4-fold as compared to the control, followed by Oat Straw (8.45-fold) and wheat Straw (6.12-fold) at the C/N ratio of 20/1, which was found to be the optimal C/N ratio for co-digestion in the present study. In addition, corn stalks achieved the highest CH4 content in the biogas (∼68%), which was about 11% higher than that of Oat Straw (∼57%), whereas wheat Straw and the control both had produced biogas with ∼47% CH4 content. Wheat Straw demonstrated a lower biogas productivity than corn stalks and Oat Straw even it had a higher carbon content (46%) than the latter two residues (39%).
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biogas and ch4 productivity by co digesting swine manure with three crop residues as an external carbon source
Bioresource Technology, 2010Co-Authors: Xiao Wu, Curtis MillerAbstract:Co-digesting swine manure with three agricultural residues, i.e., corn stalks, Oat Straw, and wheat Straw, to enhance biogas productivity was investigated in this study. A 3x3 experimental design with duplicates was adopted (3 crop residuesx3 carbon/nitrogen ratios) to examine the improvement of batch digestion in terms of biogas volume produced, CH(4) content in the biogas, and net CH(4) volume. The crop residues were first cut into small sections and then ground into fine particles smaller than 40 mesh size (0.422mm) before being added to digesters. All the digesters were run simultaneously under controlled temperature at 37+/-0.1 degrees C. The length of experiment was 25days. The results showed that all crop residues significantly increased biogas production and net CH(4) volume at all C/N ratios, among which corn stalks performed the best with increase in daily maximum biogas volume by 11.4-fold as compared to the control, followed by Oat Straw (8.45-fold) and wheat Straw (6.12-fold) at the C/N ratio of 20/1, which was found to be the optimal C/N ratio for co-digestion in the present study. In addition, corn stalks achieved the highest CH(4) content in the biogas ( approximately 68%), which was about 11% higher than that of Oat Straw ( approximately 57%), whereas wheat Straw and the control both had produced biogas with approximately 47% CH(4) content. Wheat Straw demonstrated a lower biogas productivity than corn stalks and Oat Straw even it had a higher carbon content (46%) than the latter two residues (39%).
