Effect of Hydraulic Retention Time and Sludge Retention Time on Performance of Membrane Bioreactor for Wet Season

To understand the effect of HRT and SRT on parameters was the prime motive of the studies. The parameters such as chemical oxygen demand (COD), soluble COD (Sol.COD), biochemical oxygen demand (BOD), nitrogen (ammonia NH4, nitrate NO3) contents and phosphorus contents (Phosphate PO4), total suspended solids (TSS) and volatile suspended solids (VSS), soluble microbial products (SMP), proteins, carbohydrates, acetate and alkalinity (ALK) for hospital wastewater and residential quarter wastewater were considered. The experiments have been performed on laboratory-scale hollow fiber submerged membrane bioreactor (MBR) for wet season i.e. rainy season. The results have discovered a high removal efficiency of COD, BOD and ammonia which ranged between 93.15 to 97.98 %, 94.20 to 98.74 % and 97.21 to 98.74 %, respectively. While, for TSS and VSS, the removals were found to above 99.00 %. The phosphorus removal efficiency (54.55 to 58.00 %) was found to be inadequate compare to other parameters. The removal efficiencies decreased with increase in HRT, while efficiency increased with increase in SRT. Better results were obtained with residential wastewater as compared to hospital wastewater