AWWA ACE94207
Important aspects of treated water quality for the study were turbidity, algae, disinfection byproducts (DBPs), and iron and manganese. Filtration performance goals included producing filtered water with an average turbidity of 0.10 nephelometric turbidity units or lower and attaining water production of 9000 gallons/sq ft before reaching terminal head loss of 8 feet or turbidity breakthrough, which was set at 0.2 NTU for this study. Disinfection byproduct issues are important to US water utilities in the present regulatory setting, so testing was undertaken for total organic carbon (TOC) removal and for simulated distribution system (SDS) formation of total trihalomethanes (TTHMs) and haloacetic acids (HAAs) in filtered waters, with a goal of keeping DBP formation to concentrations lower than those agreed upon in the USEPAs regulatory negotiation (80 ug/L for total trihalomethanes and 60 ug/L for haloacetic acids). The filtered water quality goal was set at less than 0.1 mg/L for iron and less than 0.1 mg/L for manganese. The treatment processes that received the major emphasis in pilot plant testing were direct filtration with and without ozone, and dissolved air flotation (DAF).
Keywords: Flotation; Direct Filtration; Ozonation; Turbidity; Algae ; Disinfection Byproducts; Iron Removal; Manganese Removal; Organic Carbon; Trihalomethanes