AWWA JAW46206

Bench and pilot scale studies of total organic carbon (TOC) removal in Lake Erie water using enhanced coagulation, ozonation, and granular activated carbon (GAC) were conducted to determine the applicability of these processes to the upgrade and expansion of the Crown Water Treatment Plant in Cleveland, Ohio. Alum-polymer blends, alum, and ferric chloride more effectively removed TOC than did polyaluminum sulfate-polymer blends. Ozone did not affect TOC concentrations but it reduced bromochloroacetic acid. Bench scale tests showed an optimal dose of 10 mg/L powdered activated carbon with 25 mg/L alum-polymer blend was needed to achieve a 39 percent reduction in TOC. Rapid, small scale column tests with GAC beds of 5- and 10-min empty bed contact time showed breakthrough at two and six days, respectively; they did not maintain 30 percent TOC reduction after 30 and 100 days, respectively. TOC removal for future control of disinfection byproducts could most effectively be achieved in Cleveland by enhanced coagulation. Includes 9 references, tables, figures.