Impact of Cl2 in the generation of ClO2 on DBPs in drinking water
Drinking water chlorination is known to produce halogenated organics such as total trihalomethanes (TTHMs), haloacetic acids (HAAs), and other chlorine-containing species. Laboratory findings show that pure chlorine dioxide, however, produces virtually no TTHMs (or other halogenated organics). In the late 1970s, the USEPA recognized replacement of chlorine with chlorine dioxide as a preoxidant and BAT (Best Available Technology) for preventing THM formation in drinking water treatment. ^ When chlorine dioxide is generated and applied, some excess chlorine may also be applied, the amount depending on the generation process and the degree of control exercised. Some of this chlorine may react with organics to produce THMs. Studies conducted in the late 70s showed, however, that the amount of THMs formed by chlorine in conjunction with chlorine dioxide is less than the quantity formed if the same dose of chlorine were fed alone. Additional work has been reported only sporadically in this area since then. There is little or no literature addressing speciation phenomena arising from mixed chlorine/chlorine dioxide treatment. This study evaluated the impact of excess chlorine in the generation of chlorine dioxide on the formation of THMs and other disinfection byproducts such as haloacetic acids in a source water having high total trihalomethane formation potential (TTHMFP) and significant bromide ions. ^
Health Sciences, Toxicology|Health Sciences, Public Health|Environmental Sciences
Rittmann, Douglas Donald, "Impact of Cl2 in the generation of ClO2 on DBPs in drinking water" (1999). ETD Collection for University of Texas, El Paso. AAI9947587.