Impact of UV disinfection combined with chlorination on bacterial community structure and the formation of trihalomethanes in drinking water

Abstract

The objective of this study was to evaluate the performance of the UV disinfection combined with chlorination in the inactivation of microorganisms and the formation of trihalomethanes (THMs). Experimental results showed that UV irradiation had obvious advantages in reducing the number of microbial species and community complexity. Under the same initial chlorine concentration, the amount of THMs increased with the UV radiation dose increasing. THMs will be reduced in the UV-chlorine disinfection process compared with the pure chlorine disinfection. In terms of number of surviving microorganisms in water, compared with a single chlorine disinfection, UV irradiation showed a very good disinfection effect. With an average 52.5% decline, the data reflected the sample after UV irradiation in microbial diversity and abundance significantly decreased. the physical and chemical properties of organic matter could be qualitatively and quantitatively described by 3DEEM.