Preozonation of bromide-bearing source water in south China

摘要

The effectiveness of preozonation was evaluated on treating a bromide-bearing dam source water in south China through batch-scale experiments. Preozonation at ozone doses of 0.5-1.0 mg/L (at ozone consumption base) enhanced total organic carbon (TOC) removal through coagulation, and resulted in an almost linear reduction of ultraviolet absorbance at 254 nm (UV_(254). The removals of TOC (after coagulation) and UV_(254 )at the ozone dose of 1.0 mg/L were 36 percent and 70 percent, respectively. Preozonation at an ozone dose between 0.5 and 1.0 mg/L resulted in the removal of disinfection byproducts formation potential (DBFP) including trihalomethane formation potential (THMFP) and haloacetic acid formation potential (HAAFP) for about 50 percent. The removals of THMFP and HAAFP decreased with the further increase of ozone dose. Ozonation of bromide-bearing water (bromide concentration, 34 mu g/L) produced a bromate concentration under the detection limit(2 mu g/L) at ozone doses <1.5 mg/L. However, bromate >10 mu g/L could be produced when the bromide concentration was increased to 96 mu g/L.