Odor pollution in landfill area has attracted more social attention in China. It is very important to control the generation of odor pollutants in situ. Analyzing odorous materials production form buried waste, simula...Odor pollution in landfill area has attracted more social attention in China. It is very important to control the generation of odor pollutants in situ. Analyzing odorous materials production form buried waste, simulated columns of different volatile solid (VS) content and different buried period waste were designed. Gas compounds produced from the columns were collected and analyzed by comprehensive two-dimensional gas chromatography (GC × GC) method. It has remarkable relationship between VS content and concentrations of odorous material. When VS content more than 40%, the total amount of odorous compounds increases remarkably. It can be inferred that reduced VS content of original waste may effective decreasing odorous materials production in landfill area. The old rubbish produced more odorous compounds than that of fresh one in simulated columns.展开更多
Volatile solid additive(VSA)has been demonstrated to be an effective strategy to optimize the morphology of the active layer for high‐performance organic solar cells(OSCs).Most of the reported OSCs with VSA are proce...Volatile solid additive(VSA)has been demonstrated to be an effective strategy to optimize the morphology of the active layer for high‐performance organic solar cells(OSCs).Most of the reported OSCs with VSA are processed by chloroform(CF)and relies on thermal annealing(TA)posttreatment.However,the CF solvent problems of low boiling point,toxicity,and environmentalunfriendly as well as increasing cost from TA restricted the large‐scale production.Here,a simple‐structured and low‐cost triazine derivative 2,4,6‐trichloro‐1,3,5‐triazine(TCT)as a VSA was introduced into PM6:BTP‐eC9‐based OSCs.Employing the TCT additive,the nonhalogenated solvent(o‐xylene)processed OSCs without TA treatment and delivered higher power conversion efficiencies(PCEs)in comparison to the TA‐treated counterpart.Benefiting from the intermolecular interactions between TCT and the active layer materials,the TCT‐treated blend films exhibited optimized morphology and enhanced crystallinity.As a result,the PM6:BTP‐eC9 OSCs achieved a champion PCE of 18.18%and fill factor(78.5%),which is among one of the most advanced nonhalogenated solvent‐processed and annealing‐free OSCs.Meanwhile,the TCT‐treated blend films also demonstrated the better photostability compared to the control device.This work provides a guideline of triazine derivatives as VSA for high‐performance OSCs with TA‐free and nonhalogenated solvent‐processing treatment.展开更多
In order to study the effect of excess sludge ozonation, a continuous experiment in lab scale process was carried out. During the treatment process, a high level of ozone was produced by the electrolysis-type ozone ge...In order to study the effect of excess sludge ozonation, a continuous experiment in lab scale process was carried out. During the treatment process, a high level of ozone was produced by the electrolysis-type ozone generator, and various parameters, such as Soluble Chemical Oxygen Demand （SCOD）, Mixed Liquor Suspended Solids （MLSS）, Mixed Liquor Volatile Suspended Solids （MLVSS）, pH and so on, which char- acterize sludge were investigated. A substantial reduction in the volume of sludge and the release of intracellular materials were observed： SCOD proliferated as a consequence of extending the ozone feeding time; MLSS and MLVSS, especially the ratio of MLVSS to MLSS, dwindled as the action time rose. Through analyzing the effluent quality and excess sludge activity, the sludge-water volume mixture ratio of 1 ： 20 with 50 -60 minutes＇ oxidation treatment was found to be the optimal condition for ozonic disintegration of excess sludge. A remarkable sludge reduction rate of 57% could be achieved under the ozone feeding time of 40 minutes, which revealed the optimal action time.展开更多
This study evaluates the effectiveness of aerobic pretreatment of municipal solid waste （MSW） on reducing lag phase and accelerating biogas generation. Aerobic pretreatment degree （APD） was determined on the basis...This study evaluates the effectiveness of aerobic pretreatment of municipal solid waste （MSW） on reducing lag phase and accelerating biogas generation. Aerobic pretreatment degree （APD） was determined on the basis of reduction in volatile solids （VS） on a wet weight basis. In this study, intermittent aeration （IA） was applied to three reactors as a main aeration mode; since a single reactor was operated under continuous aeration mode. However, the purpose of the experiment was to reduce VS content of waste, irrespective of the comparison between aeration modes. Fresh MSW was first pretreated aerobically with different aeration rates （10, 40, 60 and 85 L/min/m3） for the period of 30- 50 days, resulting in VS-loss equivalent to 20%, 27%, 38% and 53q4 on w/w basis for the wastes AI, A2, A3 and A4, respectively. The cumulative biogas production, calculated based on the modified Gompertz model were 384, 195, 353,215, and 114 L/kg VS for the wastes A0, A1, A2, A3 and A4, respectively. Untreated waste （A0） showed a long lag phase; whereas the lag phases of pretreated MSW were reduced by more than 90e/L Aerobically pretreated wastes reached stable methanogenic phase within 41 days compared to 418 days for untreated waste. The waste mass decreased by about 8% to 27% compared to untreated MSW, indicative that even more MSW could be placed in the same landfill. The study confirmed the effectiveness of aerobic pretreatment of MSW prior to landfilling on reducing lag phase and accelerating biogas generation.展开更多
Maximum methane potential(B0)is an important parameter used in assessing suitability of a substrate for biogas production.This study examined maximum methane potential of different manures generated from three major C...Maximum methane potential(B0)is an important parameter used in assessing suitability of a substrate for biogas production.This study examined maximum methane potential of different manures generated from three major Chinese livestock,namely chicken,hog and cattle,and evaluated the important factors that affect the maximum methane potential of a substrate.The livestock manures collected from the local farms were incubated under a thermophilic anaerobic condition(55℃).The results showed that the maximum methane potential(B0)of cattle,hog and chicken manures were 292.0 mL/g VS,272.0 mL/g VS and 266.4 mL/g VS,respectively.The B0 value decreases with increasing contents of crude protein and crude fat,while increases with increasing the contents of carbohydrates and crude fiber in manures.The content of NH4+-N in chicken manure was significantly higher during the digestion period,reached as high as 1962.5 mg/L by the end of incubation period.Heavy metals of Cu and Zn in the manure also affect the B0.Empirical relationships that describe the B0 decrease in response to increase of Zn and Cu contents in manure were developed and used as a simple tool to assess the effects of these metals on the B0.It was concluded that the protein,Cu and Zn contents of manure are most important chemical compositions that negatively affect maximum methane potential.Based on the three experimental manures,the maximum methane potential was limited by either ammonium content or Cu and Zn content in the manure.For a commercial biogas production facility using these manures as main feedstock,one should consider to add co-substrate or co-substrates to reduce concentration of these chemicals to maximize biogas production.展开更多
文摘Odor pollution in landfill area has attracted more social attention in China. It is very important to control the generation of odor pollutants in situ. Analyzing odorous materials production form buried waste, simulated columns of different volatile solid (VS) content and different buried period waste were designed. Gas compounds produced from the columns were collected and analyzed by comprehensive two-dimensional gas chromatography (GC × GC) method. It has remarkable relationship between VS content and concentrations of odorous material. When VS content more than 40%, the total amount of odorous compounds increases remarkably. It can be inferred that reduced VS content of original waste may effective decreasing odorous materials production in landfill area. The old rubbish produced more odorous compounds than that of fresh one in simulated columns.
基金National Natural Science Foundation of China,Grant/Award Numbers:22379167,52125306。
文摘Volatile solid additive(VSA)has been demonstrated to be an effective strategy to optimize the morphology of the active layer for high‐performance organic solar cells(OSCs).Most of the reported OSCs with VSA are processed by chloroform(CF)and relies on thermal annealing(TA)posttreatment.However,the CF solvent problems of low boiling point,toxicity,and environmentalunfriendly as well as increasing cost from TA restricted the large‐scale production.Here,a simple‐structured and low‐cost triazine derivative 2,4,6‐trichloro‐1,3,5‐triazine(TCT)as a VSA was introduced into PM6:BTP‐eC9‐based OSCs.Employing the TCT additive,the nonhalogenated solvent(o‐xylene)processed OSCs without TA treatment and delivered higher power conversion efficiencies(PCEs)in comparison to the TA‐treated counterpart.Benefiting from the intermolecular interactions between TCT and the active layer materials,the TCT‐treated blend films exhibited optimized morphology and enhanced crystallinity.As a result,the PM6:BTP‐eC9 OSCs achieved a champion PCE of 18.18%and fill factor(78.5%),which is among one of the most advanced nonhalogenated solvent‐processed and annealing‐free OSCs.Meanwhile,the TCT‐treated blend films also demonstrated the better photostability compared to the control device.This work provides a guideline of triazine derivatives as VSA for high‐performance OSCs with TA‐free and nonhalogenated solvent‐processing treatment.
基金Supported by the Fundamental Research Funds for the Central Universities(2010380003161543)Science and Technology Project of Science and Technology Department of Guangdong Province,China(2010B031700023)
文摘In order to study the effect of excess sludge ozonation, a continuous experiment in lab scale process was carried out. During the treatment process, a high level of ozone was produced by the electrolysis-type ozone generator, and various parameters, such as Soluble Chemical Oxygen Demand （SCOD）, Mixed Liquor Suspended Solids （MLSS）, Mixed Liquor Volatile Suspended Solids （MLVSS）, pH and so on, which char- acterize sludge were investigated. A substantial reduction in the volume of sludge and the release of intracellular materials were observed： SCOD proliferated as a consequence of extending the ozone feeding time; MLSS and MLVSS, especially the ratio of MLVSS to MLSS, dwindled as the action time rose. Through analyzing the effluent quality and excess sludge activity, the sludge-water volume mixture ratio of 1 ： 20 with 50 -60 minutes＇ oxidation treatment was found to be the optimal condition for ozonic disintegration of excess sludge. A remarkable sludge reduction rate of 57% could be achieved under the ozone feeding time of 40 minutes, which revealed the optimal action time.
文摘This study evaluates the effectiveness of aerobic pretreatment of municipal solid waste （MSW） on reducing lag phase and accelerating biogas generation. Aerobic pretreatment degree （APD） was determined on the basis of reduction in volatile solids （VS） on a wet weight basis. In this study, intermittent aeration （IA） was applied to three reactors as a main aeration mode; since a single reactor was operated under continuous aeration mode. However, the purpose of the experiment was to reduce VS content of waste, irrespective of the comparison between aeration modes. Fresh MSW was first pretreated aerobically with different aeration rates （10, 40, 60 and 85 L/min/m3） for the period of 30- 50 days, resulting in VS-loss equivalent to 20%, 27%, 38% and 53q4 on w/w basis for the wastes AI, A2, A3 and A4, respectively. The cumulative biogas production, calculated based on the modified Gompertz model were 384, 195, 353,215, and 114 L/kg VS for the wastes A0, A1, A2, A3 and A4, respectively. Untreated waste （A0） showed a long lag phase; whereas the lag phases of pretreated MSW were reduced by more than 90e/L Aerobically pretreated wastes reached stable methanogenic phase within 41 days compared to 418 days for untreated waste. The waste mass decreased by about 8% to 27% compared to untreated MSW, indicative that even more MSW could be placed in the same landfill. The study confirmed the effectiveness of aerobic pretreatment of MSW prior to landfilling on reducing lag phase and accelerating biogas generation.
基金Shanxi Scholarship Council of China(2013-major project No.7)Key project of Shanxi Province(20130313007-3)for financial support。
文摘Maximum methane potential(B0)is an important parameter used in assessing suitability of a substrate for biogas production.This study examined maximum methane potential of different manures generated from three major Chinese livestock,namely chicken,hog and cattle,and evaluated the important factors that affect the maximum methane potential of a substrate.The livestock manures collected from the local farms were incubated under a thermophilic anaerobic condition(55℃).The results showed that the maximum methane potential(B0)of cattle,hog and chicken manures were 292.0 mL/g VS,272.0 mL/g VS and 266.4 mL/g VS,respectively.The B0 value decreases with increasing contents of crude protein and crude fat,while increases with increasing the contents of carbohydrates and crude fiber in manures.The content of NH4+-N in chicken manure was significantly higher during the digestion period,reached as high as 1962.5 mg/L by the end of incubation period.Heavy metals of Cu and Zn in the manure also affect the B0.Empirical relationships that describe the B0 decrease in response to increase of Zn and Cu contents in manure were developed and used as a simple tool to assess the effects of these metals on the B0.It was concluded that the protein,Cu and Zn contents of manure are most important chemical compositions that negatively affect maximum methane potential.Based on the three experimental manures,the maximum methane potential was limited by either ammonium content or Cu and Zn content in the manure.For a commercial biogas production facility using these manures as main feedstock,one should consider to add co-substrate or co-substrates to reduce concentration of these chemicals to maximize biogas production.
