title: Disinfection byproduct precursor removal by enhanced coagulation and their distribution in chemical fractions.
abstract: Raw water from the Songhua River was treated by four types of coagulants, ferric chloride (FeCI3), aluminum sulfate (AI2(SO4)3), polyaluminum chloride (PACI) and composite polyaluminum (HPAC), in order to remove dissolved organic matter (DOM). Considering the disinfection byproduct (DBP) precursor treatability, DOM was divided into five chemical fractions based on resin adsorption. Trihalomethane formation potential (THMFP) and haloacetic acid formation potential (HAAFP) were measured for each fraction. The results showed that hydrophobic acids (HoA), hydrophilic matter (HiM) and hydrophobic neutral (HoN) were the dominant fractions. Although both HoN and HoA were the main THM precursors, the contribution for THMFP changed after coagulation. Additionally, HoA and HiM were the main HAA precursors, while the contribution of HoN to HAAFP significantly increased after coagulation. HoM was more easily removed than HiM, no matter which coagulant was used, especially under enhanced coagulation conditions. DOC removal was highest for enhanced coagulation using FeCI3 while DBPFP was lowest using PACI. This could indicate that not all DOC fractions contained the precursors of DBPs. Reduction of THMFP and HAAFP by PACI under enhanced coagulation could reach 51% and 59% respectively.
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. mei_stx@163.com
authors.forename: Yanmei
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Xiao
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Dongsheng
authors.initials: D
authors.lastname: Wang
authors.affiliation: Department of Environmental Engineering, Peking University, Beijing 100871, China.
authors.forename: Mingquan
authors.initials: M
authors.lastname: Yan
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Bi
mesh_terms: D005591:Chemical Fractionation / Q000379:methods*; D011232:Chemical Precipitation; D004203:Disinfection / Q000379:methods*; D045483:Rivers / Q000382:microbiology*; D014871:Water Microbiology; D018508:Water Purification / Q000379:methods