Process analysis and optimization of industrial estate wastewater treatment using conventional and compartmentalized membrane bioreactor: A comparative study

Membrane bioreactor (MBR) technology isan integrated combined system ofbiological and membrane processes to treat wastewater. MBR competently removes organic mattersand suspended solids from any type of wastewater. This study is aimed to evaluate and compare the performance of conventional and compartmentalized lab-scale MBR in treating an industrial estate wastewater (Faraman Industrial Estate, Kermanshah, Iran). The MBR systems were operated in two conditions; one in a completely stirred regime(conventional activated sludge (AS) system) and the other one in a semi plug flow regime(compartmentalized activated sludge (CAS) system). Experimental design was performed by response surface methodology (RSM) to assess the effect of two independent numerical factors i.e. hydraulic retention time (HRT) and mixed liquor volatile suspended solids (MLVSS) on nine responses.From the overall results, it was found that CAS-MBR performed better than AS-MBR.The CAS-MBR achieved 94.9 of TCOD removal efficiency at 24 h of HRT and MLVSS concentration of 10000 mg.L 1. Compared to AS MBR, CAS-MBR showed higher percentage of removal efficiency for total nitrogen andtotal Kjeldahl nitrogen. Moreover, CAS-MBR recorded the lowest SVI value of 55 mL.mg 1compared to AS-MBR. Additional microfiltration has increased the TCOD removal in both systems. As a conclusion, the CAS-MBR operated at the same condition showed higher treatment capacityin compare to AS-MBR.