Investigating the Potential of a Ceramic-Based Microbial Fuel Cell for Concomitant Nutrient Removal and Power Recovery from Rice Mill Wastewater

Abstract

Microbial fuel cells (MFCs) are emerging as a promising technology for sustainable wastewater treatment and electricity generation that utilizes microorganisms to convert organic matter into electricity. In this study, synthetic rice mill wastewater was treated in a ceramic-based MFC having a biocathode. The wastewater was pumped into the anodic chamber of the MFC, in which exoelectrogens utilized the organic matter for electricity generation, and the effluent was channelized in the cathodic chamber in which aerobic bacteria removed the pollutants from wastewater. The influence of initial chemical oxygen demand (COD) concentration was investigated by operating the MFC with four different COD concentrations ranging from 500 to 3,000 mg/L. The highest power output was observed in an MFC operated with an initial COD concentration of 2,000 mg/L. The power density obtained in an MFC operated with a graphite felt cathode (282 mW/m3) was found to be 3.4 times and 4.5 times higher than the power density obtained in MFCs operated with graphite plate and stainless-steel mesh cathodes, respectively. Almost 95% of COD, 88% of lignin, 90% of ammonia, and 87% of phosphate removal were observed in the MFC operated with the graphite felt cathode. Therefore, a dual-chamber biocathode MFC was demonstrated to be a viable method for removing nutrients and recovering electricity from wastewater.