Simultaneous organic matter removal and disinfection of wastewater with enhanced power generation in microbial fuel cell

Abstract

Presence of pathogenic microorganism in anodic effluent of microbial fuel cell (MFC) makes it unfit for reuse. In this study, performance of dual chamber MFC was evaluated in terms of organic matter removal, power generation and disinfection in cathodic chamber. Anodic effluent was treated further in cathodic chamber for achieving disinfection with different doses of sodium hypochlorite (NaOCl) with available chlorine varying from 0.67, 1.32, 2, 3 and 4 g/L. Addition of different doses of NaOCl resulted in satisfactory disinfection along with removal of nitrogenous compounds. Power output of MFC improved up to 3g/L of available chlorine (6.5 W/m(3)); however, further increase in chlorine concentration decreased the power. Voltammetric and impedance analysis showed higher and faster electron reduction and decrease in polarization resistance at 3g/L dose. Higher organic matter removal from wastewater and complete elimination of microorganism, along with improved power output, demonstrates effectiveness of hypochlorite as catholyte.

Keywords: Disinfection; Electron acceptor; Hypochlorite; Microbial fuel cells; Wastewater treatment.