Treatment of Chemical Synthesis-Based Pharmaceutical Wastewater with Combined ABR and MBR System

The performance of treating chemical synthesis-based pharmaceutical wastewater with combined ABR and MBR system was evaluated under different operating conditions: first, the system was conducted at a medium temperature (23degC-28degC), The average COD removal efficiency of ABR was constantly maintained at around 65% and the total COD removal rate of the system was from 95% to 98%. When the influent COD concentration varied from 5161 mg/L to 16740 mg/L, the final effluent COD of membrane bioreactor was 300~500 mg/L. Second, the system was conducted at low temperature (11degC-17degC). The average COD removal efficiency of ABR was only 30%-50%. MBR process supplied a large contribution to organic removal, the effluent COD stabilized at about 600 mg/L. The effluent NH₃-N concentration of ABR was higher than that in the influent obviously if it was fed raw wastewater, but the MBR which was fed the effluent from ABR had a good effect on NH₃-N removal.