Pilot Plant Optimization of the Chlorine Dioxide Treatment Process forDisinfection By-Product Reduction

摘要

Previous pilot-plant investigations conducted by the Evansville, Indiana Waterand Sewer Utility confirmed the effectiveness of chlorine dioxide treatment for reducing trihalomethane formation. These investigations resulted in a shift away from the utility's pre-chlorination practices and the implementation of raw water disinfection/oxidation using chlorine dioxide. For the past eight years, this treatment alteration has proven effective in maintaining Evansville's total trihalomethane level well below the promulgated maximum contaminant level of 0.1 mg/L. This research endeavor is focusing on the parallel pilot-plant evaluation of the disinfection alternatives of chlorine dioxide and ozone and the reduction of residual concentrations of chlorine dioxide and the inorganic by-product ions of chlorite and chlorate.