Comparison of the chemical removal rates of a low cost microbial fuel cel and an aerated activated sludge bioreacteur, and evaluation of its performances

Abstract

Microbial fuel cells can be used to reduce the organic load of a wastewater, while producing electricity at the same time. However, most tests on MFCs are done in controlled laboratory environments using synthetic wastewaters, and MFCs that contain expensive catalysts and membranes. In this work, we studied the performances of a low-cost microbial fuel cell that was made with stainless steel electrodes and no catalysts, and The COD removal in the MFC was compared to the one obtained in an aerated activated sludge bioreactor. It was found that the MFC could be used for water treatment, an 80% COD removal was reached after 15 days, compared to 90% after 10 days in the aerated reactor. However, the power densities were quite low, a maximum of 2.5 mW/m2 could be reached, this was due to high activation losses, a high internal resistance, and the presence of few electrogenic bacteria in the biocatayst.