MICROBIAL FUEL CELLS WITH THE PERFORMANCE OF WASTEWATER DENITRIFICATION BASED ON HETEROTROPHIC NITRIFICATION-AEROBIC DENITRIFIER BACTERIA

Based on the aerobic denitrifiers' ability, a microbial fuel cell was constructed with nitrogenous wastewater as substrate and aerobic denitrifier bacteria as microbial catalyst. When generating electricity, the cell could, at the same time, remove nitrogen and thus reduce the environmental pollution extent caused by the wastewater. In order to increase the efficiency of producing electricity, the anode (material is activated carbon fiber cloth) surface was modified by an embedding method to load as many as aerobic denitrifying bacteria. As a result, the power density, current density and the usage rate were raised greatly, and also the starting time of the cell was shortened from 4 days to 1 hour. As the aerobic denitrifiers could both nitrify and denitrify, two tests were held to measure the ability of nitrification. The results showed that the aerobic denitrification microbial fuel cell performed better than the heterotrophic nitrification one. The maximum output voltage of the aerobic denitrification microbial fuel cell was about 837 mV, and maximum power density of it reached 438 mW/m(2) with a current density of 523 mA/m(2). Moreover, the NO(3)(-)-N and NH(4)(+)-N removal rates of the two microbial fuel cells were 97.15 and 94.55%, respectively.