A Cascade of Miniature Microbial Fuel Cells Coupled with an Electrochemical Reactor for Energy Harvesting

This work reports the use of the Microbial Fuel Cell (MFC) technology, in combination with an electrochemical reactor, for the generation of electricity while removing Chlorella vulgaris microalgae contained in wastewater. In particular, Chlorella vulgaris algae was pre-treated by using an electrolytic cell. To this aim, a fixed bed reactor with 3D electrodes was employed. The pre-treated wastewater was used as feedstock for a 3D printed miniature air-cathode MFCs arranged in cascade for further algal removal and energy production. The performance of the system was studied by measuring the chemical oxygen demand, the optical density and the recorded voltage in all the experiments. Results show that the efficiency of the system, in terms of output energy recovery and water treatment, increases when a higher number of MFCs is used in the cascade.