Research On Microbiology And Disinfection Byproduct Control In Drinking Water By Combined Disinfectants

Chlorine is, by far, the most commonly used disinfectant in the drinking water treatment industry, Since it has been introduced into the water supply industry waterborne diseases such as typhoid and cholera have been controled effectively. as the most universal disinfectant, free chlorine plays an important role in the disinfection process. However, at the same the free chlorine killing microorganisms it also takes into the smell and taste problem and can reaction with organic compound such as humic acid in water and generate disinfection by-products such as trihalomethanes, haloacetic, these organic by-products are considered potential carcinogens.Chlorine dioxide as an alternative disinfectants, has stronger oxidation than that of free chlorine, and has a better disinfection efficacy,it also will not be replaced with the organic compounds to produce halogenated organic by-products. However, chlorine dioxide is unstable and difficult to maintain lasting disinfection effect, and also produces chlorite and other inorganic disinfection by-products.This article uses the strong oxidation of chlorine dioxide and the persistence of free chlorine to control microbial and disinfection byproduct by the combination disinfectant with free chlorine and chlorine dioxide. Experimental results indicates that:the CT value of the combination disinfectant to reached 3log killing is just of 14.9% that of free chlorine; combination disinfectant can observed 7.2log of killing, and single disinfectant for a maximum of 5.02 log and 3.42log inactivation respectively; temperature has a better on combination disinfection, pH value nearly has no effect on combination disinfection; combination disinfectant has a significantly effect on control of disinfection byproduct, it reaches a minimum proportion of 71.5%. Inorganic product control has also been reduced at least 49.5%; combination disinfectants has a remarkable effect of reduceing disinfection by-products potential,it can reduce at least 56.4%disinfection by-products potential than than that of free chlorine; inorganic by-products generated also meet the requirements of GB5749-2006. In this article, in order to introduce the combination disinfectant into water supply and better service to the society, we made a prospects of combination disinfectant.