EFFECTS OF OZONATION ON OPTIMAL COAGULANT DOSING IN DRINKING-WATER TREATMENT

This paper examines the impact of pre-ozonation on optimal coagulant d osing in drinking water treatment. The focus is on the influence of ra w water quality, coagulant type, and optimal dosing criteria on ozonat ion impacts as illustrated by results from bench and pilot-scale studi es. Pre-ozonation can lower the cationic polymer dose for effective tu rbidity removal but also results in lower dissolved organic carbon (DO G) removal by coagulation. Alum doses are either unaffected or slightl y increased for turbidity removal with minimal effects on DOC removal. Minimal effects of pre-ozonation on combined alum/polymer dosing are expected, although DOC removal can be hindered.