Removal of Natural Organic Matter from Water by Coagulation and Flocculation to Mitigate the Formation of Chlorine- Disinfection By-Products at the Thu Duc Water Treatment Plant in Vietnam
Keywords:Coagulation, Disinfection by-products (DBPs), Natural organic matter (NOM), Total organic carbon (TOC), Trihalomethanes (THMs), Removal efficiency
In this study, removal of NOM to prevent the potential formation of DBP at Thu Duc Water Treatment Plant (TDWTP) in Vietnam was investigated using coagulation-flocculation. Coagulants poly-aluminium chloride (PAC), aluminium sulphate Al2(SO4)3, and ferric chloride (FeCl3) – with polyacrylamide (PAM) as the flocculant were examined. The efficiency was characterized by turbidity, total organic carbon (TOC), and total trihalomethane (TTHM). Results showed that the optimal dosage of PAC, Al2(SO4)3, and FeCl3 was 20, 10, and 20 mg/L, respectively, while a 0.05 - 0.15 mg/L of PAM was effective dosage. The optimal pH was 7.0 (PAC), 6.0 (Al2(SO4)3), and 8.0 (FeCl3). Under optimal conditions, the turbidity removal was almost 99% with all coagulants while a maximum TOC removal of 26.6% was found with Al2(SO4)3. In all cases, TTHM was not detected. Hence, Al2(SO4)3 accompany with PAM are suggested to replace PAC which is currently used at TDWTP. Although a low efficiency in TOC removal was found, it is significant to raise a suggestion to TDWTP since the water quality monitoring now does not examine NOM and DBPs issues. Furthermore, this study provides useful information for other local water plants which employ similar raw water source and treatment processes.
SAWACO. Overview of SAWACO water supply system and current status. Ho Chi Minh City, Vietnam: Saigon Water Corporation (SAWACO), 2018.
MOC. Water Supply - Distribution System and Facilities Design Standard, TCXDVN 33-2006. Ministry of Construction of the Socialist Republic of Vietnam , Hanoi, Vietnam; 2006. p. 53-7.
MOH. The national technical regulation on drinking water quality, Standard No. QCVN 01-1:2018/MOH. Ministry of Health of the Socialist Republic of Vietnam, Hanoi, Vietnam; 2018. p. 1-8.
Zhang Y, Zhao X, Zhang X, Peng S. A review of different drinking water treatments for natural organic matter removal. Water Supply. 2015;15(3):442-55.
García I. Removal of natural organic matter to reduce the presence of trihalomethanes in drinking water: KTH Royal Institute of Technology; 2011.
Rizzo L, Selcuk H, Nikolaou A, Belgiorno V, Bekbolet M, Meric S. Formation of chlorinated organics in drinking water of Istanbul (Turkey) and Salerno (Italy). Global NEST Journal. 2005;7(1):95-105.
Tawabini B, Al-Mutair M, Bukhari A. Formation potential of trihalomethanes (THMs) in blended water treated with chlorine. Journal of Water Reuse and Desalination. 2011;1(3):172-8.
Grünwald A, Šťastný B, Slavíčková K, Slavíček M. Formation of haloforms during chlorination of natural waters. Acta Polytechnica. 2002;42(2).
Wang G-S, Deng Y-C, Lin T-F. Cancer risk assessment from trihalomethanes in drinking water. Science of the Total Environment. 2007;387(1-3):86-95.
WHO. Guidelines for drinking-water quality: Incorporating 1st and 2nd addenda. 3th Edition Volume 1, Recommendations: World Health Organization; 2008.
Andersson A, Lavonen E, Harir M, Gonsior M, Hertkorn N, Schmitt-Kopplin P, et al. Selective removal of natural organic matter during drinking water production changes the composition of disinfection by-products. Environmental Science: Water Research & Technology. 2020;6(3):779-94.
Tak S, Vellanki BP. Natural organic matter as precursor to disinfection byproducts and its removal using conventional and advanced processes: state of the art review. Journal of water and health. 2018;16(5):681-703.
Fabris R, Chow CW, Drikas M, Eikebrokk B. Comparison of NOM character in selected Australian and Norwegian drinking waters. Water research. 2008;42(15):4188-96.
Liu H, Liu R, Tian C, Jiang H, Liu X, Zhang R, et al. Removal of natural organic matter for controlling disinfection by-products formation by enhanced coagulation: A case study. Separation and purification technology. 2012;84:41-5.
Ramona C, Marcela M, Carmen T. An overview of natural organic matter removal by coagulation in drinking water treatment. Bul Inst Polit Iaşi. 2023; Vol. 68 (72):69-92.
Sillanpää M, Ncibi MC, Matilainen A, Vepsäläinen M. Removal of natural organic matter in drinking water treatment by coagulation: A comprehensive review. Chemosphere. 2018;190:54-71.
Wassink J, Andrews R, Peiris R, Legge R. Evaluation of fluorescence excitation–emission and LC-OCD as methods of detecting removal of NOM and DBP precursors by enhanced coagulation. Water Science and Technology: Water Supply. 2011;11(5):621-30.
Fabris R, Chow CW, Drikas M. Comparison of coagulant type on natural organic matter removal using equimolar concentrations. Journal of Water Supply: Research and Technology—AQUA. 2012;61(4):210-9.
Edzwald J. Coagulation in drinking water treatment: particles, organics and coagulants. Water Science and Technology. 1993;27(11):21-35.
Sulaymon AH, Ali A-FM, Al-Naseri SK. Natural organic matter removal from Tigris River water in Baghdad, Iraq. Desalination. 2009;245(1-3):155-68.
Yang Z, Gao B, Yue Q. Coagulation performance and residual aluminum speciation of Al2 (SO4) 3 and polyaluminum chloride (PAC) in Yellow River water treatment. Chemical Engineering Journal. 2010;165(1):122-32.
Dlamini S, Haarhoff J, Mamba B, Van Staden S. The response of typical South African raw waters to enhanced coagulation. Water Science and Technology: Water Supply. 2013;13(1):20-8.
Ødegaard H, Østerhus S, Melin E, Eikebrokk B. NOM removal technologies–Norwegian experiences. Drinking Water Engineering and Science. 2010;3(1):1-9.
Uyak V, Toroz I. Disinfection by-product precursors reduction by various coagulation techniques in Istanbul water supplies. Journal of hazardous materials. 2007;141(1):320-8.
Faust SD, Aly OM. Chemistry of water treatment: CRC press; 1998.
Qin J-J, Oo MH, Kekre KA, Knops F, Miller P. Impact of coagulation pH on enhanced removal of natural organic matter in treatment of reservoir water. Separation and Purification Technology. 2006;49(3):295-8.
APHA. Standard methods for the examination of water and wastewater. Washington, D.C., U.S: American Public Health Association; 2005.
MOST. Water quality - Guidelines for the determination of total organic carbon (TOC) and dissolved organic carbon (DOC), TCVN 6634:2000. Ministry of Sicence and Technology of the Socialist Republic of Vietnam, Hanoi, Vietnam; 2000.
EPA. Method 508 determination of chlorinated pesticides in water by gas chromatography with an electron capture detector - Revision 3.1. National exposure research laboratory office of research and development, U.S. Environmental Protection Agency; 1995.
MOC. TCXD 233:1999 - The parameters using for selection of the surface and groundwater resource in the water supply system. Ministry of Construction of the Socialist Republic of Vietnam , Hanoi, Vietnam, 1999.
Musikavong C, Wattanachira S, Marhaba TF, Pavasant P. Reduction of organic matter and trihalomethane formation potential in reclaimed water from treated industrial estate wastewater by coagulation. Journal of hazardous materials. 2005;127(1-3):58-67.
Crittenden JC, Trussell RR, Hand DW, Howe K, Tchobanoglous G. MWH's water treatment: principles and design: John Wiley & Sons; 2012.
NPNL. Annual Report in 2018. Vientiane Capital Water Supply State-owned Enterprise. Vientiane: Lao PDR., 2018.
Zhang Y, Shi B, Zhao Y, Yan M, Lytle DA, Wang D. Deposition behavior of residual aluminum in drinking water distribution system: Effect of aluminum speciation. Journal of Environmental Sciences. 2016;42:142-51.
Niu Z-b, Wang Y, Zhang X-J, He W-j, Han H-d, Yin P-J. Iron stability in drinking water distribution systems in a city of China. Journal of Environmental Sciences. 2006;18(1):40-6.
Kabsch-Korbutowicz M. Effect of Al coagulant type on natural organic matter removal efficiency in coagulation/ultrafiltration process. Desalination. 2005;185(1-3):327-33.
How to Cite
Copyright (c) 2023 Science & Technology Asia
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.