Utilization of residual organics of Labaneh whey for renewable energy generation through bioelectrochemical processes: Strategies for enhanced substrate conversion and energy generation

Abstract

Labaneh whey (LW) that is rich in residual organics was evaluated for bioelectricity generation using microbial fuel cell (MFC) in two different configurations namely single chamber (MFC-SC) and dual chamber (MFC-DC) MFCs. The whole study was executed in three stages: The first stage evidenced promising amount of bioelectricity generation (DC, 643 mV; SC, 545 mV) along with chemical oxygen demand removal (CODr: DC, 60.63%; SC, CODr: 55.25%). In the second phase, activity of anodic electrogenic microbes was improved with short time poising at potentials of 400, 600 and 800 mV, among which 800 mV evidenced 2.24 (DC) and 1.60 (SC) fold enhancement in power generation along with significant improvement in substrate degradation. The third phase was solely focused on bioelectrochemical treatment of LW through applied potentials for extended period. This phase achieved 89 and 94% chemical oxygen demand (COD) degradation using SC and DC configurations, respectively at 800 mV.

Keywords: Applied potential; Bioelectrochemical treatment system; Chemical oxygen demand; Enhancement strategies; Labaneh whey; Microbial fuel cells.