Characterization of precursors to trihalomethanes formation in Bangkok source water

Wang

et al. 2007

Environ Monit Assess

Dissolved organic matter (DOM) and its potential to form disinfection by-products (DBPs) during drinking water treatment raise challenges to water quality control. Understanding both chemical and physical characteristics of DOM in source waters is key to better water treatment. In this study, the DOM from four typical source waters in China was fractionated by XAD resin adsorption (RA) and ultrafiltration (UF) techniques. The trihalomethane formation potential (THMFP) of all fractions in the DOM were investigated to reveal the major THM precursors. The fraction distributions of DOM could be related to their geographical origins in a certain extent. The dominant chemical fraction as THM precursors in the DOM from south waters (East-Lake reservoir in Shenzhen and Peal rivers in Guangzhou) was hydrophobic acid (HoA). The size fraction with molecular weight (MW) <1 kDa in both south waters had the highest THMFP. The results of cluster analysis showed that the parameters of fractions including DOC percentage (DOC%), UV 254 %, SUVA 254 (specific UV 254 absorbance) and THMFP were better for representing the differences of DOM from the studied waters than specific THMFP (STHMFP). The weak correlation between SUVA 254 and STHMFP for either size or XAD fractions suggests that whether SUVA 254 can be used as an indicator for the reactivity of THM formation is highly dependent on the nature of organic matter.

Section: Sthmfp and Suva254supporting

confidence: 72%

Size and resin fractionations of dissolved organic matter and trihalomethane precursors from four typical source waters in China

Wang

et al. 2007

Environ Monit Assess

“…The Chao Phraya River Bangkok, Thailand (Panyapinyopol et al 2005) August 2003 drinking water utilities of the greater area of Quěbec City, Canada, namely Lěvis, and Sainte-Foy. In addition, CHCl 3 levels of approximately 90% were found in treated water from three other major drinking water utilities of the greater area of Quěbec City (i.e.…”

Section: Reductions Of Thmfp and Thm Speciesmentioning

confidence: 99%

Reduction of dissolved organic matter in terms of DOC, UV-254, SUVA and THMFP in industrial estate wastewater treated by stabilization ponds

Musikavong

Wattanachira

2007

Environ Monit Assess

The aim of this research was to monitor the influent and effluent water quality of the aeration, facultative and oxidation water treatment ponds of an industrial estate. This industrial estate, the largest in northern Thailand, has proposed to utilization of reclaimed treated wastewater in their raw water supply so as to cope with the yearly water shortage during the dry season. Water samples were collected four times from four sampling points and evaluated for their dissolved organic matter (DOM) content in terms of dissolved organic carbon (DOC), ultraviolet light absorbance at 254 nm (UV-254), specific ultraviolet absorption (SUVA), trihalomethane formation potential (THMFP) and trihalomethane (THM) species. Average values of DOC, UV-254, SUVA and THMFP in the influent wastewater of 12.9 mg L(-1), 0.165 cm(-1), 1.29 L mg(-1) m(-1) and 1.24 mg L(-1), respectively, were observed. The aeration ponds produced the best results: a 54% reduction of DOC, a 33% reduction of UV-254, and a 57% reduction of THMFP. However, SUVA in the aeration pond effluent showed a moderate increase. The facultative ponds and oxidation ponds did not take part in the reduction of DOC, UV-254, SUVA and THMFP. Average DOC, UV-254, SUVA and THMFP value of the treated wastewater were 5.8 mg L(-1), 0.107 cm(-1), 1.85 L mg(-1) m(-1) and 468 microg L(-1), respectively. Chloroform, at 72.6% of total THMFP, was found to be the predominant THM species.

Journal of Environmental Sciences

“…This method separates NOM into several components according to their chemical properties (hydrophilicityhydrophobicity). Based on this method, the behaviors of different NOM fractions have been investigated (Chow et al, 2005;Hua and Reckhow, 2007;Kitis et al, 2002;Krasner et al, 1996;Liang and Singer, 2003;Matilainen et al, 2011;Panyapinyopol et al, 2005). The results showed that the hydrophilic fractions of NOM are composed mostly of aliphatic carbon and nitrogen compounds (such as carbohydrates, sugars, and amino acids), while hydrophobic NOM primarily consists of humic and fulvic acids and is rich in aromatic carbon, phenolic structures and conjugated double bonds (Krasner et al, 1996).…”

Section: Introductionmentioning

confidence: 99%

Disinfection byproduct precursor removal by enhanced coagulation and their distribution in chemical fractions

Zhao

Xiao

Wang

et al. 2013

Raw water from the Songhua River was treated by four types of coagulants, ferric chloride (FeCl 3 ), aluminum sulfate (Al 2 (SO 4 ) 3 ), polyaluminum chloride (PACl) 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 FeCl 3 while DBPFP was lowest using PACl. This could indicate that not all DOC fractions contained the precursors of DBPs. Reduction of THMFP and HAAFP by PACl under enhanced coagulation could reach 51% and 59% respectively.