外阻对污泥微生物燃料电池产电以及有机物降解的影响

重点考察了不同外阻（10、150和1 000Ω）对污泥微生物燃料电池（sludge microbial fuel cell,SMFC）产电性能及有机物去除速率的影响。结果表明,外阻对电池产电和有机物降解有显著影响,低电阻有利于电流产生及有机物消耗。当外阻为10Ω时,输出电流最高（4.2 mA）,且污泥溶解性化学需氧量（SCOD）去除速率最快（53 mg.d-1）。DGGE图谱显示,不同外阻导致阳极微生物菌落结构有明显差异;CV扫描发现外阻对生物膜氧化还原能力有显著影响,低电阻下运行的阳极生物膜氧化还原活性较强。本研究为理解外阻与阳极生物膜间的关系提供一条有益线索,也为MFC性能提高提供一条可操作性的途径。

The effect of different external resistance on electricity generation and organic matter degradation in a sludge microbial fuel cell

This paper studied the effect of different external resistances （10 Ω, 150 Ω and 1 000 Ω） on electricity generation and organic matter degradation in a sludge microbial fuel cell （SMFC）. The result showed that the highest current of 4.2 mA and organic degradation rate of 53 mg·d^-1was achieved from the SMFC working at the smallest resistance, while the highest power density of 50.3 mW/m^2 was obtained at 150 Ω when it was close to the internal resistance. Denaturing gradient gel electrophoresis （DGGE） assay indicated that the anodic bacterial communities differed from each other under various external loading conditions. Cyclic voltammetries （CVs） displayed that the external resistance had a certain influence on the redox activity of the anodic hiofilms in which the most electrochemical activity biofilm was formed at 10 Ω among others. The results provided us very important clues to understand the relationship between the external resistances and the anodic biofilms, and also suggested a potential approach to improve the performance of the MFCs.