Treatment of Mixed Pharmaceutical Industry and Domestic Wastewater by Sequencing Batch Reactor

摘要

Raw mixed pharmaceutical industry and domestic wastewater characteristics are such as BOD_5 = 90-130 mg L~(-1), COD = 200-300 mg L~(-1), SS = 900 mg L~(-1), pH = 6.4-6.8, T = 20℃, NH_3=26 mg L~(-1), PO_4~(3-) = 8.5 mg L~(-1). In treatment plant, the parameters such as BOD_5, NH_3, PO_4~(3-), SS, MLVSS, pH, temperature, sludge volume and microorganisms predominance are studied, under constant sedimentation time (30 min) against variable aeration times. As a second step, the same parameters are studied under the constant aeration time (4h) against variable sedimentation times. Effluent concentrations from sequencing batch reactor (SBR) are determined BOD_5 = 13-18mgL~(-1), COD = 25-37 mg L~(-1), SS = 9-21mgL~(-1), pH = 7.3-7.6, TDF = 1-2, T = 23℃, NH_3= 1 mg L~(-1), PO_4~(3-) = 8.1 mg L~(-1). At the end of 6 h of aeration time, the efficiency of BOD_5 reaches to 83%. The efficiency of BOD_5 reaches to 81% under a 4h aeration time and at 90 min sedimentation time. As a result, the optimum treatment efficiency has been taken under 4 h of aeration time and of 60 min of sedimentation time.