【背景】甲烷厌氧氧化(anaerobic oxidation of methane,AOM)包含反硝化型甲烷厌氧氧化和硫酸盐还原型甲烷厌氧氧化。目前,人们向水体中排放过量的含氮及含硫污染物,引起了严重的环境污染和生态破坏。【目的】利用甲烷厌氧氧化微生物燃...【背景】甲烷厌氧氧化(anaerobic oxidation of methane,AOM)包含反硝化型甲烷厌氧氧化和硫酸盐还原型甲烷厌氧氧化。目前,人们向水体中排放过量的含氮及含硫污染物,引起了严重的环境污染和生态破坏。【目的】利用甲烷厌氧氧化微生物燃料电池(microbial fuel cell,MFC)研究同步脱氮除硫耦合反应机理及反应过程中微生物的多样性信息。【方法】构建了3个微生物燃料电池(N-S-MFC、N-MFC、S-MFC),以甲烷作为唯一碳源,探究其同步脱氮除硫性能,并采用16S rRNA基因高通量测序技术对微生物群落结构进行分析。【结果】N-S-MFC中硝酸盐和硫酸盐的去除率分别为90.91%和18.46%。阳极室中微生物的相对丰度提高,与反硝化及硫酸盐还原菌相关的微生物大量富集,如门水平上拟杆菌门(Bacteroidota)、厚壁菌门(Firmicutes)和脱硫杆菌门(Desulfobacterota),同时属水平上Methylobacterium_Methylorubrum、Methylocaldum、Methylomonas等常见的甲烷氧化菌增多。【结论】N-S-MFC促进了硝酸盐还原,而对硫酸盐还原几乎无影响,本研究为甲烷MFC在污水中同步脱氮除硫的应用提供理论依据。展开更多
Microbial fuel cells(MFCs)rely on microbial conversion of organic substrates to electricity.The optimal performance depends on the establishment of a microbial community rich in electrogenic bacteria.Usually this micr...Microbial fuel cells(MFCs)rely on microbial conversion of organic substrates to electricity.The optimal performance depends on the establishment of a microbial community rich in electrogenic bacteria.Usually this microbial community is established from inoculation of the MFC anode chamber with naturally occurring mixed inocula.In this study,the electrochemical performance of MFCs and microbial community evolution were evaluated for three inocula including domestic wastewater(DW),lake sediment(LS)and biogas sludge(BS)with varying substrate loading(L_(sub))and external resistance(R_(ext))on the MFC.The electrogenic bacterium Geobacter sulfurreducens was identified in all inocula and its abundance during MFC operation was positively linked to the MFC performance.The LS inoculated MFCs showed highest abundance(18% ± 1%)of G.sulfurreducens,maximum current density [I_(max)=(690 ± 30)m A·m^(-2)] and coulombic efficiency(CE = 29% ± 1%)with acetate as the substrate.Imaxand CE increased to(1780 ± 30)m A·m^(-2)and 58% ± 1%,respectively,after decreasing the R_(ext) from 1000 Ω to 200 Ω,which also correlated to a higher abundance of G.sulfurreducens(21% ± 0.7%)on the MFC anodic biofilm.The data obtained contribute to understanding the microbial community response to Lsub and R_(ext)for optimizing electricity generation in MFCs.展开更多
基金grateful to Danida Fellowship Centre for supporting the research project (Biobased electricity in developing countries,DFC No.11-091 Ris?)The financial support from China Scholarship Council (CSC No.2011635051) for Guotao Sun is gratefully acknowledged.Annette E.Jensen,DTU is thanked for technical support
文摘Microbial fuel cells(MFCs)rely on microbial conversion of organic substrates to electricity.The optimal performance depends on the establishment of a microbial community rich in electrogenic bacteria.Usually this microbial community is established from inoculation of the MFC anode chamber with naturally occurring mixed inocula.In this study,the electrochemical performance of MFCs and microbial community evolution were evaluated for three inocula including domestic wastewater(DW),lake sediment(LS)and biogas sludge(BS)with varying substrate loading(L_(sub))and external resistance(R_(ext))on the MFC.The electrogenic bacterium Geobacter sulfurreducens was identified in all inocula and its abundance during MFC operation was positively linked to the MFC performance.The LS inoculated MFCs showed highest abundance(18% ± 1%)of G.sulfurreducens,maximum current density [I_(max)=(690 ± 30)m A·m^(-2)] and coulombic efficiency(CE = 29% ± 1%)with acetate as the substrate.Imaxand CE increased to(1780 ± 30)m A·m^(-2)and 58% ± 1%,respectively,after decreasing the R_(ext) from 1000 Ω to 200 Ω,which also correlated to a higher abundance of G.sulfurreducens(21% ± 0.7%)on the MFC anodic biofilm.The data obtained contribute to understanding the microbial community response to Lsub and R_(ext)for optimizing electricity generation in MFCs.
