Maximization of energy recovery from starchy wastewater by integrating dark fermentation with microbial fuel cell

Abstract

Dark fermentative effluents were used as substrates in Microbial fuel cells (MFCs) and the power outputs of MFCs were improved by optimization of influential anodic operational parameters. An initial power density of 1.4 W/m3 was obtained by an enriched mixed electrogenic which was further increased to 5.43 W/m3 by optimization of influential anodic parameters. By utilizing various dark fermentative effluents as substrates, the power densities were further enhanced to 6.2 W/m3 with an average COD removal efficiency of 70–80% and a columbic efficiency of 10.55 %. An overall energy recovery of 40.59% was obtained by integrating dark-fermentation-microbial fuel cell processes. This study presents a simple strategy for generating power from various dark fermentative effluents and thus provides a potential scope for MFCs to be integrated with dark fermentation process for enhanced energy recovery and simultaneous wastewater treatment.