Investigation of the use of chlorine based advanced oxidation in surface water: Oxidation of natural organic matter and formation of disinfection byproducts

Disinfection byproduct (DBP) formation during the treatment of raw Colorado River Water (CRW) using aqueous chlorine and ultraviolet (UV) light advanced oxidation processes (AOPs) was investigated. Here, CRW was combined with aqueous chlorine from two distinct sources (electrochemically-generated Mixed Oxidant Solution (MOS) and commercial sodium hypochlorite) and then exposed to ultraviolet C (UV-C) and ultraviolet A (UV-A) light. The impact of the treatment process on the structure of (NOM) in the CRW was examined, as well as the resulting production of various halogenated organic Disinfection By-Products (DBPs). Both AOP conditions tested resulted in destruction of chromophoric components of the NOM, while formation of total amounts of haloacetic acids and trihalomethanes was far below the US EPA regulated maximum contaminant level values for these contaminants, even though the UV and chlorine doses used in these studies were much higher than the typical doses used in an actual treatment process.