Electricity generation from food wastes and microbial community structure in microbial fuel cells

Microbial fuel cell (MFC) was studied as an alternate and a novel way to dispose food wastes (FWs) in a waste-to-energy form. Different organic loading rate obviously affected the performance of MFCs fed with FWs. The maximum power density of ∼18 W/m3 (∼556 mW/m2) was obtained at COD of 3200 ± 400 mg/L and the maximum coulombic efficiency (CE) was ∼27.0% at COD of 4900 ± 350 mg/L. The maximum removals of COD, total carbohydrate (TC) and total nitrogen (TN) were ∼86.4%, ∼95.9% and ∼16.1%, respectively. Microbial community analysis using 454 pyrosequencing of 16S rRNA gene demonstrated the combination of the dominant genera of the exoelectrogenic Geobacter and fermentative Bacteroides effectively drove highly efficient and reliable MFC systems with functions of organic matters degradation and electricity generation.