Microbial Fuel Cells for Nitrate Removal in Ground Water

摘要

The increasing nitrate concentration in groundwater has become a serious concern all over the world. In this study, the double chamber microbial fuel cell (MFC) and single chamber MFC systems were proposed for simultaneous removal of chemical oxygen demand (COD) and nitrate (NO3- - N). Transforming the various variables (cathod materials, external resistance and initial concentrations of NO3- - N) of double chamber MFC to determine the optimal operating parameters. Observing the treatment effect of single chamber MFC when adding an external resistance. The results showed: in the case of connecting external circuit, the double chamber MFC could reach the best degradation effect of NO3- - N and COD when cathode and anode materials are made of stainless steel velvet, the external resistance of 100 Ω and the initial concentrations of NO3- - N of around 250 mg/L. The best degradation rate of NO3- - N and COD reached 66.88% and 82.85% respectively. Adding an external solar power to single chamber could enhance the treatment effect; specifically, NO3- - N and COD removal rate reached 65.06% and 70.42% respectively, 6.14% and 9.73% higher than without external power.