Hydrothermal carbonization(HTC)of biomass is a promising method to produce carbonaceous materials.The work presented in this article addresses the application of hydrothermal carbonization(HTC)to produce a solid fuel...Hydrothermal carbonization(HTC)of biomass is a promising method to produce carbonaceous materials.The work presented in this article addresses the application of hydrothermal carbonization(HTC)to produce a solid fuel named HTC-Biochar,whose characteristics are comparable to lignite coal.Biogas sludge(SD),maize silage(MS),and barley silage(BS)as a substrates were hydrothermally carbonized in a 1.5 L batch reactor at 200C for 6 h.The effect of mixing ratios of different substrates on HTC was investigated.Chemical compositions and combustion characteristics of hydro-chars obtained from mono-and co-carbonization were evaluated.Result showed that HTC increased carbon contents and higher heating values(HHV)by 1.4–14.4%and 13–36%,respectively.The evolution of the H/C and O/C atomic ratios indicated that dehydration and decarboxylation occurred during hydrothermal carbonization for all samples.Furthermore,a significant synergistic enhancement was observed for HHV and carbon content.A mixing ratio of 1:1 for BS and SD showed the best performance for co-HTC.In summary,hydrothermal co-carbonization is a promising strategy to tailor high-performance hydro-char for energy applications.展开更多
Cotton stalks(CS)are lignocellulosic agricultural by-products,a potential source for biogas production,but pretreatment must be considered since hydrolysis is the rate-limiting stage for lignocellulosic biomass substr...Cotton stalks(CS)are lignocellulosic agricultural by-products,a potential source for biogas production,but pretreatment must be considered since hydrolysis is the rate-limiting stage for lignocellulosic biomass substrates.This study investigates the feasibility of mechanical pretreatment of CS to enhance methane production.Batch anaerobic digestion of CS samples with particle sizes ranging from 0.5 to 65 mm was carried out in 1 L eudiometer batch digesters for 48 days at 37◦C.Results showed that methane yield was inversely proportional to particle size,and the quality of biogas was good(54.0-55.2%CH_(4)).Significant increases in methane yield were observed with 20.3%and 26%for samples with a particle size of 3 mm and 0.5 mm,respectively,compared to untreated CS.The coefficient of anaerobic energy turnover was relatively low(20.2-25.5%).Reduction of the CS particle size to 3 mm or less is recommended to achieve effective methane conversion and decrease the retention time in an anaerobic digester from 31 to about 25 days.However,to offset the high energy demand required for grinding,further research should be conducted in combining size reduction with chemical and physicochemical pretreatment.展开更多
Methane potential of three-phase olive mill solid waste(3POMSW)was evaluated by biochemical methane potential(BMP)tests at temperatures of 37.5◦C and 55◦C.The results have shown,that thermophilic processing has a high...Methane potential of three-phase olive mill solid waste(3POMSW)was evaluated by biochemical methane potential(BMP)tests at temperatures of 37.5◦C and 55◦C.The results have shown,that thermophilic processing has a higher methane and biogas yield by 10%and 17.2%,respectively,compared to mesophilic conditions.Concluding thermophilic conditions of 3POMSW results in higher conversion of the feedstock into biogas.The result of addition of enzymes(MethaPlus,Hemicellulase,PectinaseL,Amylase S and Lipase)and their mixtures to 3POMSW at 55◦C has shown that the optimum mixture of enzymes was Metha Plus and Hemicellulase,which resulted in an increase of methane yield by 1.3%compared to the base case without addition of enzymes.Simple model equations were developed based on first-order kinetic in order to calculate the biogas yield versus the time as a function of reaction rate constant(k)and the maximum biogas yield(ymax).In this study,results have shown two different reaction rates obtained for the mixtures of enzymes with 3POMSW of 0.130 d^(-1) from t=0…14 days and 0.034 d^(-1) from t=28…63 days.The developed simple model equations can be applied for calculating the biogas yield at the time and by optimizing the process improving biological nutrient removal.展开更多
文摘Hydrothermal carbonization(HTC)of biomass is a promising method to produce carbonaceous materials.The work presented in this article addresses the application of hydrothermal carbonization(HTC)to produce a solid fuel named HTC-Biochar,whose characteristics are comparable to lignite coal.Biogas sludge(SD),maize silage(MS),and barley silage(BS)as a substrates were hydrothermally carbonized in a 1.5 L batch reactor at 200C for 6 h.The effect of mixing ratios of different substrates on HTC was investigated.Chemical compositions and combustion characteristics of hydro-chars obtained from mono-and co-carbonization were evaluated.Result showed that HTC increased carbon contents and higher heating values(HHV)by 1.4–14.4%and 13–36%,respectively.The evolution of the H/C and O/C atomic ratios indicated that dehydration and decarboxylation occurred during hydrothermal carbonization for all samples.Furthermore,a significant synergistic enhancement was observed for HHV and carbon content.A mixing ratio of 1:1 for BS and SD showed the best performance for co-HTC.In summary,hydrothermal co-carbonization is a promising strategy to tailor high-performance hydro-char for energy applications.
文摘Cotton stalks(CS)are lignocellulosic agricultural by-products,a potential source for biogas production,but pretreatment must be considered since hydrolysis is the rate-limiting stage for lignocellulosic biomass substrates.This study investigates the feasibility of mechanical pretreatment of CS to enhance methane production.Batch anaerobic digestion of CS samples with particle sizes ranging from 0.5 to 65 mm was carried out in 1 L eudiometer batch digesters for 48 days at 37◦C.Results showed that methane yield was inversely proportional to particle size,and the quality of biogas was good(54.0-55.2%CH_(4)).Significant increases in methane yield were observed with 20.3%and 26%for samples with a particle size of 3 mm and 0.5 mm,respectively,compared to untreated CS.The coefficient of anaerobic energy turnover was relatively low(20.2-25.5%).Reduction of the CS particle size to 3 mm or less is recommended to achieve effective methane conversion and decrease the retention time in an anaerobic digester from 31 to about 25 days.However,to offset the high energy demand required for grinding,further research should be conducted in combining size reduction with chemical and physicochemical pretreatment.
文摘Methane potential of three-phase olive mill solid waste(3POMSW)was evaluated by biochemical methane potential(BMP)tests at temperatures of 37.5◦C and 55◦C.The results have shown,that thermophilic processing has a higher methane and biogas yield by 10%and 17.2%,respectively,compared to mesophilic conditions.Concluding thermophilic conditions of 3POMSW results in higher conversion of the feedstock into biogas.The result of addition of enzymes(MethaPlus,Hemicellulase,PectinaseL,Amylase S and Lipase)and their mixtures to 3POMSW at 55◦C has shown that the optimum mixture of enzymes was Metha Plus and Hemicellulase,which resulted in an increase of methane yield by 1.3%compared to the base case without addition of enzymes.Simple model equations were developed based on first-order kinetic in order to calculate the biogas yield versus the time as a function of reaction rate constant(k)and the maximum biogas yield(ymax).In this study,results have shown two different reaction rates obtained for the mixtures of enzymes with 3POMSW of 0.130 d^(-1) from t=0…14 days and 0.034 d^(-1) from t=28…63 days.The developed simple model equations can be applied for calculating the biogas yield at the time and by optimizing the process improving biological nutrient removal.
