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Qian Y, Shi Y, Guo J, Chen Y, Hanigan D, An D. Molecular characterization of disinfection byproduct precursors in filter backwash water from 10 drinking water treatment plants. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 856:159027. [PMID: 36167135 DOI: 10.1016/j.scitotenv.2022.159027] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 09/16/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
Organic matter reacts with chlorine forming disinfection byproducts (DBPs) including trihalomethanes (THMs), haloacetamides (HAMs), haloacetic acids (HAAs), and haloacetonitriles (HANs). Filter backwash water (FBW) is either released back to the environment or recycled to the head of the treatment plant after solids settling and the remaining dissolved organic matter is a significant pool of DBP precursors that are not well understood. We characterized dissolved organic matter in FBW from 10 treatment plants and low molecular weight (MW < 1 kDa) organic matter contributed the most to DBP formation. We demonstrated overall similarity of the molecular composition (e.g., elemental ratios, m/z, DBE) of the 10 samples of FBW by Fourier transform ion cyclotron resonance mass spectrometry. Aromatic and more highly oxidized compounds preferentially reacted with chlorine, forming DBPs. Low MW (<450 Da) aliphatic compounds, and highly unsaturated and phenolic compounds were the primary precursors of THMs, HANs, and HAMs, and the formation potentials (FPs) of these groups of DBPs were correlated with multiple individual molecular formulae. HAA FPs were correlated with low MW, highly unsaturated and phenolic compounds. These advances in the understanding of the molecular composition of DBP precursors in FBW may develop the effective strategies to control DBP formation and limit impacts on the quality of finished water, and can be expanded to understanding DBP precursors in drinking water sources.
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Affiliation(s)
- Yunkun Qian
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200238, PR China
| | - Yijun Shi
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200238, PR China
| | - Jun Guo
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200238, PR China
| | - Yanan Chen
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200238, PR China
| | - David Hanigan
- Department of Civil and Environmental Engineering, University of Nevada, Reno, NV 89557-0258, USA
| | - Dong An
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200238, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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Qian Y, Hu Y, Chen Y, An D, Westerhoff P, Hanigan D, Chu W. Haloacetonitriles and haloacetamides precursors in filter backwash and sedimentation sludge water during drinking water treatment. WATER RESEARCH 2020; 186:116346. [PMID: 32866929 DOI: 10.1016/j.watres.2020.116346] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 07/27/2020] [Accepted: 08/23/2020] [Indexed: 06/11/2023]
Abstract
Haloacetonitriles (HANs) and haloacetamides (HAMs) are nitrogenous disinfection byproducts that are present in filter backwash water (FBW) and sedimentation sludge water (SSW). In many cases FBW and SSW are recycled to the head of drinking water treatment plants. HAN and HAM concentrations in FBW and SSW, without additional oxidants, ranged from 6.8 to 11.6 nM and 2.9 to 3.6 nM of three HANs and four HAMs, respectively. Upon oxidant addition to FBW and SSW under formation potential conditions, concentrations for six HANs and six HAMs ranged from 92.2 to 190.4 nM and 42.2 to 95.5 nM, respectively. Therefore, at common FBW and SSW recycle rates (2 to 10% of treated water flows), the precursor levels in these recycle waters should not be ignored because they are comparable to levels present in finished water. Brominated HAN and chlorinated HAM were the dominant species in FBW and SSW, respectively. The lowest molecular weight ultrafiltration fraction (< 3 kDa) contributed the most to HAN and HAM formations. The hydrophilic (HPI) organic fraction contributed the greatest to HAN precursors in sand-FBW and SSW and were the most reactive HAM precursors in both sand- or carbon-FBWs. Fluorescence revealed that aromatic protein-like compounds were dominant HAN and HAM precursors. Therefore, strategies that remove low molecular weight hydrophilic organic matter and aromatic protein-like compounds will minimize HAN and HAM formations in recycled FBW and SSW.
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Affiliation(s)
- Yunkun Qian
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200238, China
| | - Yue Hu
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200238, China
| | - Yanan Chen
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200238, China
| | - Dong An
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200238, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
| | - Paul Westerhoff
- School of Sustainable Engineering and the Built Environment, Ira A. Fulton Schools of Engineering, Arizona State University, Tempe, AZ 85287-3005, United States
| | - David Hanigan
- Department of Civil and Environmental Engineering, University of Nevada, Reno, NV 89557-0258, United States
| | - Wenhai Chu
- State Key Laboratory of Pollution Control and Resources Reuse, National Centre for International Research of Sustainable Urban Water System, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
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Application of a Low Cost Ceramic Filter for Recycling Sand Filter Backwash Water. WATER 2018. [DOI: 10.3390/w10020150] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The aim of this study is to examine the application of a low cost ceramic filter for the treatment of sand filter backwash water (SFBW). The treatment process is comprised of pre-coagulation of SFBW with aluminum sulfate (Alum) followed by continuous filtration usinga low cost ceramic filter at different trans-membrane pressures (TMPs). Jar test results showed that 20 mg/L of alum is the optimum dose for maximum removal of turbidity, Fe, and Mn from SFBW. The filter can be operated at a TMP between 0.6 and 3 kPa as well as a corresponding flux of 480–2000 L/m2/d without any flux declination. Significant removal, up to 99%, was observed forturbidity, iron (Fe), and manganese (Mn). The flux started to decline at 4.5 kPa TMP (corresponding flux 3280 L/m2/d), thus indicated fouling of the filter. The complete pore blocking model was found as the most appropriate model to explain the insight mechanism of flux decline. The optimum operating pressure and the permeate flux were found to be 3 kPa and 2000 L/m2/d, respectively. Treated SFBW by a low cost ceramic filter was found to be suitable to recycle back to the water treatment plant. The ceramic filtration process would be a low cost and efficient option to recycle the SFBW.
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Recycling of activated carbon filter backwash water using ultrafiltration: Membrane fouling caused by different dominant interfacial forces. J Memb Sci 2017. [DOI: 10.1016/j.memsci.2017.09.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Tan Y, Lin T, Jiang F, Dong J, Chen W, Zhou D. The shadow of dichloroacetonitrile (DCAN), a typical nitrogenous disinfection by-product (N-DBP), in the waterworks and its backwash water reuse. CHEMOSPHERE 2017; 181:569-578. [PMID: 28467950 DOI: 10.1016/j.chemosphere.2017.04.118] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Revised: 04/20/2017] [Accepted: 04/24/2017] [Indexed: 06/07/2023]
Abstract
Dichloroacetonitrile (DCAN) is one of nitrogenous disinfection by-products (N-DBPs) with strong cytotoxicity and genotoxicity. In this study, the formation potential (FP) of DCAN was investigated in the samples of six important water sources located in the Yangtze River Delta. The highest formation concentration of DCAN was 9.05 μg/L in the water sample taken from Taihu Lake with the lowest SUVA value. After the NOM fractionation, the conversion rate of hydrophilic fraction to DCAN was found the highest. Subsequently, a waterworks using Taihu Lake as water source was chosen to research the FP variations of DCAN in the treatment process and backwash water. The results showed that, compared to the conventional treatment process, O/biological activated carbon (BAC) process increased the removal efficiency of DCAN from 21.89% to 50.58% by removing aromatic protein and soluble biological by-products as main precursors of DCAN. The DCAN FP in the effluent of BAC filters using old granular activated carbon was higher than that in the influent and the DCAN FP of its backwash water was lower than that in raw water. In the backwash water of sand filters, the DCAN FP higher than raw water required the recycle ratio less than 5% to avoid the accumulation of DCAN.
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Affiliation(s)
- Yiwen Tan
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Tao Lin
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China.
| | - Fuchun Jiang
- Suzhou City Water Company Limited, Suzhou, 215002, PR China
| | - Jian Dong
- Suzhou City Water Company Limited, Suzhou, 215002, PR China
| | - Wei Chen
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Dongju Zhou
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China
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Mahdavi M, Amin MM, Mahvi AH, Pourzamani H, Ebrahimi A. Metals, heavy metals and microorganism removal from spent filter backwash water by hybrid coagulation-UF processes. JOURNAL OF WATER REUSE AND DESALINATION 2017. [DOI: 10.2166/wrd.2017.148] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Abstract
Abstract
Spent filter backwash water (SFBW) reuse has attracted particular attention, especially in countries that experience water scarcity. It can act as a permanent water source until the water treatment plant is working. In this study, the concentrations of Fe, Al, Pb, As, and Cd with total and fecal coliform (TC/FC) were investigated in raw and treated SFBW by hybrid coagulation-UF processes. The pilot plant consisted of pre-sedimentation, coagulation, flocculation, clarification, and ultrafiltration (UF) units. Poly-aluminum ferric chloride (PAFCL) and ferric chloride (FeCl3) were used as pretreatment. The results showed that, at the optimum dose of PAFCl, the average removal of TC and FC was 88 and 79% and with PAFCl-UF process, it reached 100 and 100%, respectively. For FeCl3, removal efficiency of TC and FC were 81 and 72% and by applying FeCl3-UF process, it reached 100 and 100%, respectively. In comparison with FeCl3, PAFCl showed better removal efficiency for Fe, Pb, As, and Cd, except residual Al concentration. Coagulation-UF process could treat SFBW efficiently and treated SFBW could meet the US-EPA drinking water standard. Health risk index values of Fe, AL, Pb, AS, and Cd in treated SFBW indicate no risk of exposure to the use of this water.
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Affiliation(s)
- Mokhtar Mahdavi
- Environment Research Center, Isfahan University of Medical Sciences, Isfahan, Iran and Student Research Committee and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mohammad Mehdi Amin
- Environment Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Amir Hossein Mahvi
- Center for Solid Waste Research, Institute for Environmental Research, Tehran University of Medical Science, Tehran, Iran
| | - Hamidreza Pourzamani
- Environment Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Afshin Ebrahimi
- Environment Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
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Wang H, He F, Zhi Z, Gu P. The Effects of Pre-Treated Membrane Backwash Water on the Quality of Finished Water from a Membrane System. SEP SCI TECHNOL 2011. [DOI: 10.1080/01496395.2011.580306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Huang C, Lin JL, Lee WS, Pan JR, Zhao B. Effect of coagulation mechanism on membrane permeability in coagulation-assisted microfiltration for spent filter backwash water recycling. Colloids Surf A Physicochem Eng Asp 2011. [DOI: 10.1016/j.colsurfa.2011.01.054] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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McCormick NJ, Porter M, Walsh ME. Disinfection by-products in filter backwash water: implications to water quality in recycle designs. WATER RESEARCH 2010; 44:4581-4589. [PMID: 20561666 DOI: 10.1016/j.watres.2010.05.042] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Revised: 05/25/2010] [Accepted: 05/26/2010] [Indexed: 05/29/2023]
Abstract
The overall purpose of this research was to investigate disinfection by-product (DBP) concentrations and formation potential in filter backwash water (FBWW) and evaluate at bench-scale the potential impact of untreated FBWW recycle on water quality in conventional drinking water treatment. Two chlorinated organic compound groups of DBPs currently regulated in North America were evaluated, specifically trihalomethanes (THMs) and haloacetic acids (HAAs). FBWW samples were collected from four conventional filtration water treatment plants (WTP) in Nova Scotia, Canada, in three separate sampling and plant audit campaigns. THM and HAA formation potential tests demonstrated that the particulate organic material contained within FBWW is available for reaction with chlorine to form DBPs. The results of the study found higher concentrations of TTHMs and HAA9s in FBWW samples from two of the plants that target a higher free chlorine residual in the wash water used to clean the filters (e.g., clearwell) compared to the other two plants that target a lower clear well free chlorine residual concentration. Bench-scale experiments showed that FBWW storage time and conditions can impact TTHM concentrations in these waste streams, suggesting that optimization opportunities exist to reduce TTHM concentrations in FBWW recycle streams prior to blending with raw water. However, mass balance calculations demonstrated that FBWW recycle practice by blending 10% untreated FBWW with raw water prior to coagulation did not impact DBP concentrations introduced to the rapid mix stage of a plant's treatment train.
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Affiliation(s)
- N J McCormick
- Department of Civil and Resource Engineering, Dalhousie University, Halifax, Nova Scotia, Canada
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Ates N, Yilmaz L, Kitis M, Yetis U. Removal of disinfection by-product precursors by UF and NF membranes in low-SUVA waters. J Memb Sci 2009. [DOI: 10.1016/j.memsci.2008.11.044] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Gottfried A, Shepard AD, Hardiman K, Walsh ME. Impact of recycling filter backwash water on organic removal in coagulation-sedimentation processes. WATER RESEARCH 2008; 42:4683-4691. [PMID: 18789473 DOI: 10.1016/j.watres.2008.08.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Revised: 08/06/2008] [Accepted: 08/12/2008] [Indexed: 05/26/2023]
Abstract
The overall purpose of this research was to examine the impacts of filter backwash water (FBWW) and membrane backwash water (MBWW) recycles on water quality in coagulation-sedimentation processes. Specifically, the impact of recycling 5 or 10% by volume of FBWW and MBWW with surface water on the removal of natural organic matter (NOM) was evaluated at bench-scale using a standard jar-test apparatus and measurement of specific water quality parameters including total organic carbon (TOC), dissolved organic carbon (DOC), UV254, turbidity, total aluminum and zeta potential. The results of jar test conducted on a source water with a specific UV absorbance (SUVA) value within the range of 2-4 mg/Lm showed a significantly higher removal of DOC from the raw water that was blended with 5 and 10% by volume of FBWW as compared to control trials where backwash water was not added. Increasing rates of MBWW that did not contain destabilized hydroxide precipitates did not significantly change DOC concentrations in the settled water samples as compared to the control trials. For source waters that are characterized as having low turbidity with medium SUVA values, these results could hold particular significance for plants that have reached treatment ceilings in terms of dissolved NOM removal using conventional coagulation designs.
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Affiliation(s)
- A Gottfried
- Department of Civil and Resource Engineering, Dalhousie University, 1360 Barrington Street, Halifax, Nova Scotia, Canada
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