Effects of ultrasonication on the DBP formation and toxicity during chlorination of saline wastewater effluents  

作　　者：Yu Li Wanxin Li Xiangru Zhang Jingyi Jiang 

机构地区：[1]School of Environment,Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of Environment,South China Normal University,Guangzhou 510006,China [2]Department of Civil and Environmental Engineering,Hong Kong University of Science and Technology,Hong Kong,China

出　　处：《Journal of Environmental Sciences》2022年第7期326-335,共10页环境科学学报（英文版）

基　　金：supported by the Research Grants Council of Hong Kong, China (Nos. 16212518 , 16210221 , T21-711/16R , and T21-705/20-N);the Guangdong Basic and Applied Basic Research of the Joint Regional Fund, Guangdong, China (No. 2019A1515110569)。

摘　　要：Chlorine disinfection of saline wastewater effluents rich in bromide and iodide forms relatively toxic brominated and iodinated disinfection byproducts(DBPs). Ultrasonication is a relatively new water treatment technology, and it is less sensitive to suspended solids in wastewaters. In this study, we examined the effects of ultrasonication(in terms of reactor type and combination mode with chlorination) on the DBP formation and toxicity in chlorinated primary and secondary saline wastewater effluents. Compared with the chlorinated wastewater effluent samples without ultrasonication, ultrasonic horn pretreatment of the wastewater effluent samples reduced the total organic halogen(TOX) levels in chlorination by ~30%, but ultrasonic bath pretreatment of the wastewater samples did not significantly change the TOX levels in chlorination, which might be attributed to the higher energy utilization and decomposition extent of organic DBP precursors in the ultrasonic horn reactor. Moreover, the TOX levels in the chlorinated samples with ultrasonic horn pretreatment(USH–chlorination), simultaneous treatment(chlorination + USH) and subsequent treatment(chlorination–USH) were also significantly reduced, with the maximum TOX reductions occurring in the samples with ultrasonic horn pretreatment. A toxicity index was calculated by weighting and summing the levels of total organic chlorine, total organic bromine and total organic iodine in each treated sample. The calculated toxicity index values of the chlorinated wastewater effluent samples followed a descending rank order of “chlorination” > “chlorination + USH” > “chlorination–USH” > “USH–chlorination”, with the lowest toxicity occurring in the samples with ultrasonic horn pretreatment. Then, a developmental toxicity bioassay was conducted for each treated sample. The measured toxicity index values of the chlorinated wastewater samples followed the same descending rank order.

关 键 词：Disinfection byproducts DBPS CHLORINATION Ultrasonication Developmental toxicity 

分 类 号：X703[环境科学与工程—环境工程]