Treatment of Hospital Wastewater by Novel Nano-Filtration Membrane Bioreactor (NF-MBR)

Abstract

In this paper a pilot-scale membrane bioreactor (MBR) equipped with nano-membranes treating the hospital wastewaters has been studied in order to evaluate the removal of nutrients. The main goal was to examine the feasibility of the NF-MBR used to treat hospital wastewater. Process efficiency was evaluated in terms of COD, NH N, NO _N, NO _N and PO -P removal. The pilot plant located at the Babol Clinic Hospital, 3 3 3 4 _ Babol, Mazandaran, Iran. The performance of NF-MBR pilot for biological nutrient removal was evaluated during 62 days of operation. The NF-MBR resulting in respective HRT of 2.9 h. The influent COD, NH _N and 3 PO -P averaged at 688, 11.8 and 3 mg/l respectively. The final treated effluent COD, NH3_N and PO4-P for the same 4 period averaged 35, 1.69 and 0.89 mg/l respectively. The operating results of the pilot plant demonstrate that the NF- MBR process is both effective and efficient in meeting the water discharge and reuse quality requirements at the hospital. The NF-MBR showed a high COD removal, stable and complete nitrification. The biological nutrient removal efficiencies were high from the start of operation with COD and NH N removal efficiencies of 92 ± 4% and 3 _ 88 ± 2, respectively. During the course of the experiment PO -P removal efficiencies increased and finally PO -P 4 4 removal efficiency of 68% was achieved. Indicating that the NF-MBR effluent can be directly discharged into natural waters and it's suitable for reuse.