Investigation and optimization of the novel UASB-MFC integrated system for sulfate removal and bioelectricity generation using the response surface methodology (RSM)

► COD/sulfate ratio and HRT influence the performance of UASB-MFC system. ► Power output and sulfate removal efficiency increase first and then decrease. ► The response surface methodology is performed to optimize the system. ► The simulation is undistorted and optimized results are reliable.