厌氧发酵污泥燃料电池处理含铬废水的效能及机理

以厌氧发酵污泥为阳极底物、Cr(VI)为阴极电子受体构建双室微生物燃料电池(MFC),考察厌氧发酵污泥MFC系统处理含铬废水的性能及机理,并与原污泥MFC系统进行比较.发酵污泥MFC系统的开路电压为1.05V,最大功率密度为5722mW/m3,比原污泥MFC系统提高了57.8%.发酵污泥MFC系统的表观内阻为119.1Ω,比原污泥MFC系统降低了8.5%.发酵污泥MFC系统对Cr(VI)的去除符合一级动力学模型,速率常数为0.0514h-1,比原污泥MFC系统提高了36.7%.污泥经厌氧发酵后可溶性有机物浓度增加,产生了大量短链脂肪酸,它们是产电微生物易于摄取的阳极底物,因而提高了MFC系统的产电性能及Cr(VI)去除效果.

Efficacy and mechanism of microbial fuel cell treating Cr(VI)-containing wastewater with anaerobically fermented sludge as substrate

A double-chamber microbial fuel cell (MFC) was constructed with anaerobically fermented sludge as substrate in the anode chamber and Cr (VI) as electron acceptor in the cathode chamber. Both efficacy and mechanism of this new MFC system were investigated and results were compared with the former system. The former MFC showed an open-circuit voltage of 1.05V. Its maximal power density was found to be 5722 mW/m3, which was 57.8% higher than the former MFC system. The apparent internal resistance of the current MFC was 119.1Ω, which was 8.5% lower than that of the fomer MFC. Cr (VI) removal in both MFCs fitted the first-order kinetic model. The rate coefficient of Cr (VI) removal in the current MFC was 0.0514h-1, which was 36.7% higher than that in the former MFC. After anaerobic fermentation of the sludge, concentration of the soluble organic matters, especially short-chain fatty acids, were obviously increased. These products were easily assimilated by the microorganisms for electricity production, which led to enhancements of electricity production and Cr (VI) removal in the former MFC.