Occurrence of Haloacetic acids in water treatment processes of a water supply works, North China

The concentrations of four haloacetic acids (HAAs) were determined in a water supply works, North China. The highest total HAAs concentration in drinking water was found to be 79.31μg·L -1 in conventional treatment process which exceeded the drinking water standard of U.S EPA, when Huanghe River water was used as raw water. Further study indicated that prechlorination largely contributed to high concentration of HAAs in drinking water. Finally, the total concentration of HAAs was decreased from 79.31 to 3.92μg·L -1 when using an advanced treatment process consisting of K_2MnO_4 preoxidation, floatation, filtration, ozonation, active carbon adsorption, chloride ammonia disinfection.