Surface floating, air cathode, microbial fuel cell with horizontal flow for continuous power production from wastewater

A surface floating, air cathode, microbial fuel cell (MFC) with a horizontal flow is devised and characterized using glucose-based synthetic wastewater. The performance of the MFC is significantly affected by the current-collector of the electrodes. When graphite foil ribbon (150 cm) serves as the current-collector, the respective specific internal resistance and maximum power density are 0.362 Ω m−2 and 124.0 W m−3. The internal resistance can be reduced by increasing the length of the current-collector. For a graphite ribbon current-collector 256 cm long, the specific internal resistance is only 0.187 Ω m−2 and the maximum power density markedly increases to 253.6 W m−3; however, the maximum power density is affected by the current-collector material. When the current-collector is changed to a stainless-steel wire, the maximum power density is reduced to approximately 100 W m−3 because of its high liquid|solid interfacial impedance. During three continuous months of operation, issues such as leaking are not observed and as such, the MFC could be easily scaled-up for wastewater treatment by increasing the electrode size and stacking a number of cells without additional ohmic resistance.