Microbial fuel cell for effluent treatment and sustainable power generation

Microbial Fuel Cell (MFC) is an attractive and sustainable option for the conversion of effluent organics into bioelectricity. In the present study, vertically configured MFC reactors have been designed to simulate a real wastewater treatment plant so that enhanced degradation of effluent organics and sustained electrical power generation could be achieved. Anaerobic biomass and tannery effluent was used as anolyte, KMnO4 (39 mM) in phosphate buffer (700 mM) was used as catholyte. The concept of diligent mechanical disintegration has been introduced to increase the microbial activity, intended to enhance both degradation of effluent organics and generation of electricity. The operating parameters of MFC were optimized by RSM, implemented in batch studies and further extended for continuous operation. In batch studies the COD removal of 72% and 85%, with a power generation of 0.21 and 0.32 mW was achieved in 20 days HRT, whereas in continuous studies the COD removal was 57% and 72.5% in HRT of 1 day, and the power generation was 0.34 and 0.57 mW for control and experimental runs, respectively. Thus, the continuous mode of operation was beneficial than batch mode. Further, the generated power, illumination of LEDs could be demonstrated.