Investigation of various anode and cathode materials in electrochemical membrane bioreactors for mitigation of membrane fouling

Abstract

In this study, a lab-scale Electro Membrane Bio-Reactor (EMBR) was operated for investigation of the effects of types of anode/cathode materials (Fe, Cu, SS, and Al) and electrical field (1 and 3 V) on reduction of membrane fouling. In addition, operating conditions such as, anode-cathode distance and cathode-membrane distance were investigated. Results suggest that Extracellular Polymeric Substances (EPS) and Soluble Microbial Products (SMP) in the MBR increase during filtration. EMBR demonstrates significantly lower EPS and SMP values, which is confirmed by Fourier Transform Infrared (FTIR) analysis. The results showed that Fe/Al material type for cathode and anode, electrode gap of 1.5 cm and voltage of 1 V (EMBR6) performed better in reducing membrane fouling and decreased carbohydrate (EPSc, SMPc), protein (EPSp, SMPp) and membrane fouling by 53.33%, 56.95%, and 77%, respectively. In addition, the high efficiency of COD removal was obtained for the EMBR under operational conditions of EMBR6 by 99.82% and the applied voltage reduces sludge production by 80% in these conditions. There are no reports regarding effect of electrochemical operational conditions (anode/cathode material, electrodes distance, and applied voltage) on EMBR performance, which provides significant information on understanding of the EMBR mechanism. In current study, the main aim is to provide an optimum electrochemical operational condition for EMBR in order to reduce membrane fouling effectively.