Bioelectricity production from fermentable household waste in a dual-chamber microbial fuel cell.

In this study, the use of a dual-chamber microbial fuel cell for the production of bioelectricity from a food residue biomass (FORBI) product was investigated. Food residue biomass was produced by drying and shredding the pre-sorted fermentable fraction of household food waste collected door-to-door in the Municipality of Halandri, Athens, Greece. Different organic loads of food residue biomass expressed as chemical oxygen demand (COD) were examined (0.7, 0.9, 1.4, 2.8, 6 and 14 g COD L, respectively). It was observed that an increase of the initial concentration of the final extract resulted in a corresponding increase in the operating time. The microbial fuel cell potential increased from 33.3 mV to 46 mV as the concentration was increased from 0.7 to 14 g COD L. The best performance in terms of maximum power density (29.6 mW m) corresponding to a current density of 88 mA m was observed for 6 g COD L. Setting the external resistance at its optimal value (R = 2 kΩ) as determined by polarisation experiments, P drastically increased to 13.7 and 17.3 Joule (g FORBI) in two consecutive cycles. The results demonstrate that readily biodegradable substrates, such as food residue biomass, can be effectively used for enhanced bioelectricity harvesting in a microbial fuel cell.