摘要
Identification and characterization of disinfection by-product(DBP)precursors could help optimize drinkingwater treatment processes and improve the quality of finishedwater.This study comprehensively investigated the characteristics of dissolved organic matter(DOM),the hydrophilicity and molecule weight(MW)of DBP precursor and DBP-associated toxicity along the typical full-scale treatment processes.The results showed that dissolved organic carbon and dissolved organic nitrogen content,the fluorescence intensity and the SUVA254 value in raw water significantly decreased after the whole treatment processes.Conventional treatment processes were in favor of the removal of high-MW and hydrophobic DOM,which are important precursors of trihalomethane and haloacetic acid.Compared with conventional treatment processes,Ozone integrated with biological activated carbon(O3-BAC)processes enhanced the removal efficiencies of DOM with different MW and hydrophobic fractions,leading to a further decrease in almost all DBP formation potential and DBP-associated toxicity.However,almost 50%of the detected DBP precursors in raw water has not been removed after the coagulation-sedimentation-filtration integrated with O3-BAC advanced treatment processes.These remaining precursors were found to be mainly hydrophilic and low-MW(<1.0 kDa)organics.Moreover,they would largely contribute to the formation of haloacetaldehydes and haloacetonitriles,which dominated the calculated cytotoxicity.Since current drinking water treatment process could not effectively control the highly toxic DBPs,the removal of hydrophilic and low-MW organics in drinking water treatment plants should be focused on in the future.
基金
This work was supported by the National Key Research and Development Program of China(No.2021YFC3200700)
the National Natural Science Foundation of China(No.52170009)
the International Cooperation Project of Shanghai Science and Technology Commission(No.20230714100)
the Shanghai Soft Science Project(No.20692113900)
the Fundamental Research Funds for the Central Universities.