Effects of electrode surface area on the performance of microbial fuel cells with the aging landfill leachate as substrate

Bio-cathode microbial fuel cells (MFCs) were built to treat the aging landfill leachate; the effect of electrode surface area on the aging landfill leachate treatment and electrical performance of MFCs was investigated. The results show that for three sets of bio-cathode MFCs with the ratios of anode area to cathode area being 1:2, 2:2 and 2:1, the stable maximum output voltages are 408, 452 and 396mV, respectively, with the maximum electric power density of 145.73, 237.65 and 136.50mW/m³, the resistance of 350, 200 and 400Ω, and COD removal rate of 21.18%, 20.20% and 22.31%, respectively. After running for 30 days, the concentration of ammonia, nitrate and nitrite nitrogen in landfill leachate is decreased; the ammonia removal rates for the three sets of MFCs are 80.88%, 73.61% and 66.17%, respectively, which is related to the electricity generation of MFCs.