폐수처리장의 배출수 특성에 따른 CODMn 자동측정기기 분석 평가

Abstract

From year 2008, the Korean Government has been continuously monitoring water quality of effluent from mid to large wastewater treatment plants (WWTPs) with on-line analyzers at the discharging point of each plant. The water quality parameters under surveillance include pH, SS, COD or BOD, TN, and TP. For determining COD of wastewater, automated analyzers based on different chemical oxidants are being applied. Among them, the most frequently applied oxidants are permanganate and photo-oxidant. In fact, since wastewater COD can be determined with analyzers based on using different oxidants, sometimes results can be reported according to the wastewater characteristics; it is because they have different oxidation powers. In this study, on-line COD analyzers were applied to continuously monitor the water quality of effluent from three different industrial WWTPs to investigate their analytical characteristics. The WWTPs where the analyzers were installed are for livestock wastewater, for petroleum wastewater, and for electronic wastewater. In general, the analyzers produced relatively large errors according to wastewater characteristics. Therefore, it was concluded that it should be very cautious to select an COD analyzer for monitoring effluent water quality of a WWTP.