In this study,the effects of organic sulfur on anaerobic biological processes were investigated by operating two up-flow anaerobic sludge blanket(UASB)reactors with sodium dodecylbenzene sulfonate(SDBS)as a representa...In this study,the effects of organic sulfur on anaerobic biological processes were investigated by operating two up-flow anaerobic sludge blanket(UASB)reactors with sodium dodecylbenzene sulfonate(SDBS)as a representative of organic sulfur.The results indicated that the specific methanogenic activity(SMA)and chemical oxygen demand(COD)removal efficiency of R2(with SDBS added)were higher than those of R1(without SDBS)when the COD/SO_(4)^(2−)ratio was above 5.0.However,when the COD/SO_(4)^(2−)ratio was lower than 5.0,the sulfate reduction efficiency of R2 was higher than that of R1.These results and the observed SDBS transformation efficiency in anaerobic reactors indicate that low concentrations of SDBS accelerate methane production and the continuous accumulation of SDBS does not weaken the reduction of sulfate.Similarly,the calculated electron flux for a COD/SO_(4)^(2−)ratio of 1.0 indicates that the utilization intensity of electrons by sulfate-reducing bacteria(SRB)in R2 was 36.48%higher than that of SRB in R1 and exceeded that of methane-producing archaea(MPA)under identical working conditions.Moreover,the addition of SDBS in R2 made sulfidogenesis the dominant reaction at low COD/SO_(4)^(2−),and Methanobacterium and Methanobrevibacter with H_(2)/CO_(2)as the substrate and Desulfomicrobium were the dominant MPA and SRB,respectively.However,methanogenesis was still the dominant reaction in R1,and Methanosaeta with acetic acid as the substrate and Desulfovibrio were the dominant MPA and SRB,respectively.展开更多
In order to investigate the change of ecological characteristics due to the decrease of COD/SO_4^(2-) ratio during sulfate reduction, continuous-flew tests were conducted in an acidogenic sulfate-reducing reactor with...In order to investigate the change of ecological characteristics due to the decrease of COD/SO_4^(2-) ratio during sulfate reduction, continuous-flew tests were conducted in an acidogenic sulfate-reducing reactor with molasses wastewater as sole organic carbon source and sodium snlfate as electron acceptor, and the change of pH value, oxidation reduction potential (ORP), volatile fat acids (VFAs), alkalinity (ALK) and the predominant populations with COD/SO_4^(2-) ratio decreasing from 4.2 to 2.0 were investigated. The experimental results demonstrated that, with decreasing COD/SO_4^(2-) ratio, ORP and ALK increased, pH value decreased, and the proportion of acetic acid in terminal products decreased significantly, and a stable -type microbial community with high COD/SO_4^(2-) ratio was converted into a sub -stable -type one with low COD/SO_4^(2-) ratio.展开更多
基金the Fundamental Research Funds for the Central Universities(2019XKQYMS78)for the support of this study.
文摘In this study,the effects of organic sulfur on anaerobic biological processes were investigated by operating two up-flow anaerobic sludge blanket(UASB)reactors with sodium dodecylbenzene sulfonate(SDBS)as a representative of organic sulfur.The results indicated that the specific methanogenic activity(SMA)and chemical oxygen demand(COD)removal efficiency of R2(with SDBS added)were higher than those of R1(without SDBS)when the COD/SO_(4)^(2−)ratio was above 5.0.However,when the COD/SO_(4)^(2−)ratio was lower than 5.0,the sulfate reduction efficiency of R2 was higher than that of R1.These results and the observed SDBS transformation efficiency in anaerobic reactors indicate that low concentrations of SDBS accelerate methane production and the continuous accumulation of SDBS does not weaken the reduction of sulfate.Similarly,the calculated electron flux for a COD/SO_(4)^(2−)ratio of 1.0 indicates that the utilization intensity of electrons by sulfate-reducing bacteria(SRB)in R2 was 36.48%higher than that of SRB in R1 and exceeded that of methane-producing archaea(MPA)under identical working conditions.Moreover,the addition of SDBS in R2 made sulfidogenesis the dominant reaction at low COD/SO_(4)^(2−),and Methanobacterium and Methanobrevibacter with H_(2)/CO_(2)as the substrate and Desulfomicrobium were the dominant MPA and SRB,respectively.However,methanogenesis was still the dominant reaction in R1,and Methanosaeta with acetic acid as the substrate and Desulfovibrio were the dominant MPA and SRB,respectively.
基金Sponsored by the National Natural Science Foundation of China(Grant No. 50208006)the Scientific Research Foundation of Harbin Institute of Technology(Grant No. HIT. 2001.51)
文摘In order to investigate the change of ecological characteristics due to the decrease of COD/SO_4^(2-) ratio during sulfate reduction, continuous-flew tests were conducted in an acidogenic sulfate-reducing reactor with molasses wastewater as sole organic carbon source and sodium snlfate as electron acceptor, and the change of pH value, oxidation reduction potential (ORP), volatile fat acids (VFAs), alkalinity (ALK) and the predominant populations with COD/SO_4^(2-) ratio decreasing from 4.2 to 2.0 were investigated. The experimental results demonstrated that, with decreasing COD/SO_4^(2-) ratio, ORP and ALK increased, pH value decreased, and the proportion of acetic acid in terminal products decreased significantly, and a stable -type microbial community with high COD/SO_4^(2-) ratio was converted into a sub -stable -type one with low COD/SO_4^(2-) ratio.
