Electrochemically enhancement of the anaerobic baffled reactor performance as an appropriate technology for treatment of municipal wastewater in developing countries

Abstract

Abstract This work was aimed at investigating the performance of the anaerobic baffled reactor (ABR) for treatment of municipal wastewater at various hydraulic retention time (HRT). An effort was also made to improve the performance of ABR opting two strategies of effluent recirculation and electrochemical process integration. The mean steady-state removal of TSS, tCOD (total chemical oxygen demand), sCOD (soluble COD) and BOD (biochemical oxygen demand) at HRT of 48 h was 93 ± 1, 89 ± 1, 82 ± 1 and 92 ± 1%, respectively. The performance of ABR decreased when the HRT was decreased from 48 to 24 h. The effluent recirculation did not improve the performance of ABR. The integration of electrochemical process with the ABR (EABR) using a pair of electrodes (steel or aluminum) could enhance the removal of contaminants in the ABR. The EABR with steel electrodes at the current density of 0.1 mA cm −2 at the HRT of 24 h could decrease the concentrations of TSS, tCOD, BOD, sulfate and phosphate in the wastewater to the standard limits for discharge into surface water bodies. Therefore, EABR is a promising and efficient technology appropriate for domestic wastewater treatment mainly in the developing countries.