EVALUATION OF PERACETIC ACID FOR DISINFECTION OF FILTERED SECONDARY EFFLUENT AT WASHINGTON SUBURBAN SANITARY COMMISSION

摘要

Study objectives were: Evaluate PAA disinfection to meet an E. coli permit requirements; Determine PAA dose to achieve current E. coli effluent levels; and Evaluate impact of PAA on other WQ parameters. The study used pilot reactor to simulate a contact chamber. Flow was maintained for to achieve Ct of 30 min. PAA doses ranged from 0.5-2.5 mg/L. PAA doses < 1.0 mg/L met the permit limit of 126 MPN/100 mL but not the goal of < 10 MPN/100 mL. At doses of 1.0 & 1.5 mg/L, both the permit limit and goal were achieved. PAA residuals varied from less than 0.1-1.54 mg/L after a 30-min. contact time. Residuals exceeded 1.0 mg/L at only two sampling events. At 60 minutes of contact time all PAA residuals were below 1 mg/L regardless of initial concentration. The study demonstrated PAA can provide effective disinfection at WSSC.