Bioelectrochemical treatment of actual carwash wastewater associated with sustainable energy generation in three-dimensional microbial fuel cell

Abstract

Carwash garages are worldwide cleaning facilities. Discharge of their untreated or improperly treated wastewaters highly contributes to the pollution of water resources. Sodium dodecyl sulfate (SDS), a widely used anionic surfactant in the carwash shampoos represents the major constituent of the carwash wastewater. In this study, a new configuration of three-dimensional MFC packed with irregular shaped graphite granules to support and join the plain anodes in the anodic section. The performance of the 3D-MFC was evaluated in two operational modes; continuous and batch. The evaluation was carried out mainly in terms of the removal efficiency of organic content, in particular SDS as well as oil and grease associated with bioenergy generation from actual carwash wastewater used to fuel the MFC. The results demonstrated that maximum removal efficiencies of COD, SDS, and oil and grease were 87%, 88%, and 90%, respectively. Also, the results demonstrated that during the continuous mode operation maximum current density and power output were 1786 mA/m3 and 482 mW/m3, respectively. At batch operation mode, the maximum current density and power output were 1793 mA/m3 and 478 mW/m3, respectively indicating that the performance of the 3D-MFC was comparable in both operation modes.