Selection of drinking water treatment process to effectively remove precursors of disinfection byproducts

Dissolved organic matter (DOM) in drinking water sources is the main precursors of disinfection by-products (DBPs). To control the formation of DPBs, most of the dissolved organic matter should be removed during the drinking water treatment process. The removal rates of DOM in different water treatment processes are quite different based on the molecular weight distribution of DOM. To understand how DOM will be removed in different treatment processes and further affects the formation of the DPBs, five kinds of water treatment processes, which includes conventional process, pre-oxidation by O₃ or KMnO₄, and advanced treatment by O₃-granular activated carbon, are designed and applied in this study. Disinfection by-products formation potential (DPBFP) of the treated water by different treatment processes were detected by gas chromatography. Results show that the treatment process combined pre-O₃, conventional process and O₃-GAC is the optimum combination to remove precursors of disinfection by-products. More than 71% of trihalomethanes and haloacetic acids can be removed by this kind of combined treatment process.