Algae cathode microbial fuel cells for electricity generation and nutrient removal from landfill leachate wastewater

Landfill leachate is one of the most toxic and difficult-to-treat wastewater due to its high level of contamination and complex composition. In this study, landfill leachate at different percentages (5-40%) was fed to algae cathode microbial fuel cells (MFCs) for electricity generation along with chemical oxygen demand (COD) and nutrient removal. Maximum cell voltage of 300 ± 11 mV was obtained with 5% leachate, but the cell voltage decreased with an increase in leachate percentage. The maximum dissolved oxygen (DO) was 19.57 mg/L with 5% leachate. The COD in the anode chamber was almost completely removed (97%) with all leachate percentages, while the maximum COD removal was 52% with 10% leachate in the cathode chamber. Enhanced nitrogen and phosphorus removal was observed with leachate percentages less than 10%, but nitrogen removal efficiency was significantly reduced and even more phosphorus was observed with leachates higher than 25% (NH4+N = 651 mg/L). This study suggests that leachate can be treated at an appropriate dilution with simultaneous electricity generation in algae cathode MFC.