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Lin J, Yang L, Zhuang WE, Wang Y, Chen X, Niu J. Tracking the changes of dissolved organic matter throughout the city water supply system with optical indices. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 358:120911. [PMID: 38631164 DOI: 10.1016/j.jenvman.2024.120911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 03/22/2024] [Accepted: 04/12/2024] [Indexed: 04/19/2024]
Abstract
Dissolved organic matter (DOM) is important in determining the drinking water treatment and the supplied water quality. However, a comprehensive DOM study for the whole water supply system is lacking and the potential effects of secondary water supply are largely unknown. This was studied using dissolved organic carbon (DOC), absorption spectroscopy, and fluorescence excitation-emission matrices-parallel factor analysis (EEM-PARAFAC). Four fluorescent components were identified, including humic-like C1-C2, tryptophan-like C3, and tyrosine-like C4. In the drinking water treatment plants, the advanced treatment using ozone and biological activated carbon (O3-BAC) was more effective in removing DOC than the conventional process, with the removals of C1 and C3 improved by 17.7%-25.1% and 19.2%-27.0%. The absorption coefficient and C1-C4 correlated significantly with DOC in water treatments, suggesting that absorption and fluorescence could effectively track the changes in bulk DOM. DOM generally remained stable in each drinking water distribution system, suggesting the importance of the treated water quality in determining that of the corresponding network. The optical indices changed notably between distribution networks of different treatment plants, which enabled the identification of changing water sources. A comparison of DOM in the direct and secondary water supplies suggested limited impacts of secondary water supply, although the changes in organic carbon and absorption indices were detected in some locations. These results have implications for better understanding the changes of DOM in the whole water supply system to help ensure the supplied water quality.
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Affiliation(s)
- Jinjin Lin
- College of Environment and Safety Engineering, Fuzhou University, Fuzhou, Fujian, PR China
| | - Liyang Yang
- College of Environment and Safety Engineering, Fuzhou University, Fuzhou, Fujian, PR China.
| | - Wan-E Zhuang
- College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, Fujian, PR China
| | - Yue Wang
- Fuzhou Water Group Company, Ltd, Fuzhou, Fujian, PR China
| | - Xiaochen Chen
- College of Environment and Safety Engineering, Fuzhou University, Fuzhou, Fujian, PR China
| | - Jia Niu
- Fujian Engineering Research Center of Water Pollution Control and System Intelligence Technology, School of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, PR China.
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2
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Shi S, Wang F, Hu Y, Zhou J, Zhang H, He C. Effects of running time on biological activated carbon filters: water purification performance and microbial community evolution. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:21509-21523. [PMID: 38393555 DOI: 10.1007/s11356-024-32421-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 02/07/2024] [Indexed: 02/25/2024]
Abstract
Ozone-biologically activated carbon (BAC) filtration is an advanced treatment process that can be applied to remove recalcitrant organic micro-pollutants in drinking water treatment plants (DWTPs). In this study, we continuously monitored a new and an old BAC filter in a DWTP for 1 year to compare their water purification performance and microbial community evolution. The results revealed that, compared with the new filter, the use of the old BAC filter facilitated a slightly lower rate of dissolved organic carbon (DOC) removal. In the case of the new BAC filter, we recorded general increases in the biomass and microbial diversity of the biofilm with a prolongation of operating time, with the biomass stabilizing after 7 months. For both new and old BAC filters, Proteobacteria and Acidobacteria were the dominant bacterial phyla. At the genus level, the microbial community gradually shifted over the course of operation from a predominance of Herminiimonas and Hydrogenophaga to one predominated by Bradyrhizbium, Bryobacter, Hyphomicrobium, and Pedomicrobium, with Bradyrhizobium being established as the most abundant genus in the old BAC filter. Regarding spatial distribution, we detected reductions in the biomass and number of operational taxonomic units with increasing biofilm depth, whereas there was a corresponding increase in microbial diversity. However, compared with the effects of time, the influence of depth on the composition of the biofilm microbial community was considerably smaller. Furthermore, co-occurrence network analysis revealed that the microbial community network of the new filter after 11 months of operation was the most tightly connected, although its modular coefficient was the lowest of those assessed. We speculate that the positive and negative interactions within the network may be attributable to symbiotic or competitive relationships among species. Moreover, there may have been a significant negative interaction between SWB02 and Acidovorax, plausibly associated with a competition for substrates.
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Affiliation(s)
- Shuangjia Shi
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
| | - Feifei Wang
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China.
| | - Yulin Hu
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
| | - Jie Zhou
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
| | - Haiting Zhang
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
| | - Chiquan He
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
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3
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Sarkar K, Wei G, Rosadi MY, Murata N, Li F. Characterization of DOM released from bacteria in response to chlorine in water based on indicator bacteria E. coli. ENVIRONMENTAL TECHNOLOGY 2024; 45:193-207. [PMID: 35852481 DOI: 10.1080/09593330.2022.2102939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 07/11/2022] [Indexed: 06/15/2023]
Abstract
ABSTRACTIn this study, Escherichia coli (E. coli) was used as an indicator bacterium treated with five different concentrations of chlorine (0.1; 0.5; 1.0; 2.0, and 5.0 mg/L) and without chlorine (0.0 mg/L) to evaluate the changes in the DOM characteristics. The dissolved organic carbon (DOC) concentration initially increased along with the chlorine concentrations and decreased after 24 h (0.0 and 0.1 mg/L) and 168 h (0.5; 1.0; 2.0 and 5.0 mg/L). Ultra-violet absorbance at 260 nm (UV260) showed that the absorbance decreased for control without chlorine (0.0 mg/L) and 0.1 mg/L chlorine, while increased for other concentrations of chlorine within 120 h. The DOC and UV260 results indicated that the high concentrations of chlorine initiated high contents of DOM which contained more humic-like molecules than the DOM released from E. coli without chlorine. Fluorescence excitation-emission matrix (EEM) analysis suggested that the DOM released from E. coli without chlorine enriched with protein-like substances, whereas the fulvic-like and humic-like substances more intensified in the DOM for the high concentrations of chlorine (>1.0 mg/L). The molecular weight distribution of DOM showed that the intensity of high molecular weight substances and polydispersity increased along with chlorine concentration and contact time, whereas the low molecular weight substances were relatively higher in the DOM for control without chlorine. The obtained results of this study would be useful for a better understanding of the variation of DOM during treatment and could be used as an important reference for optimizing the operation condition of the water treatment plants.
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Affiliation(s)
- Kanika Sarkar
- Graduate School of Engineering, Gifu University, Gifu, Japan
| | - Gengrui Wei
- School of Environment and Energy, South China University of Technology, Guangzhou, People's Republic of China
| | | | | | - Fusheng Li
- Graduate School of Engineering, Gifu University, Gifu, Japan
- River Basin Research Centre, Gifu University, Gifu, Japan
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4
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Park JW, Boxall J, Maeng SK. Predicting heterotrophic plate count exceedance in tap water: A binary classification model supervised by culture-independent data. WATER RESEARCH 2023; 242:120172. [PMID: 37307683 DOI: 10.1016/j.watres.2023.120172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 06/01/2023] [Accepted: 06/02/2023] [Indexed: 06/14/2023]
Abstract
Culture-independent data can be utilized to identify heterotrophic plate count (HPC) exceedances in drinking water. Although HPC represents less than 1% of the bacterial community and exhibits time lags of several days, HPC data are widely used to assess the microbiological quality of drinking water and are incorporated into drinking water standards. The present study confirmed the nonlinear relationships between HPC, intact cell count (ICC), and adenosine triphosphate (ATP) in tap water samples (stagnant and flushed). By using a combination of ICC, ATP, and free chlorine data as inputs, we show that HPC exceedance can be classified using a 2-layer feed-forward artificial neural network (ANN). Despite the nonlinearity of HPC, the best binary classification model showed accuracies of 95%, sensitivity of 91%, and specificity of 96%. ICC and chlorine concentrations were the most important features for classifiers. The main limitations, such as sample size and class imbalance, were also discussed. The present model provides the ability to convert data from emerging measurement techniques into established and well-understood measures, overcoming culture dependence and offering near real-time data to help ensure the biostability and safety of drinking water.
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Affiliation(s)
- Ji Won Park
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Republic of Korea
| | - Joby Boxall
- Department of Civil and Structural Engineering, University of Sheffield, S13JD, United Kingdom
| | - Sung Kyu Maeng
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Republic of Korea.
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Schurer R, de Ridder DJ, Schippers JC, Hijnen WAM, Vredenbregt L, van der Wal A. Advanced drinking water production by 1 kDa hollow fiber nanofiltration - Biological activated carbon filtration (HFNF - BACF) enhances biological stability and reduces micropollutant levels compared with conventional surface water treatment. CHEMOSPHERE 2023; 321:138049. [PMID: 36746252 DOI: 10.1016/j.chemosphere.2023.138049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/13/2023] [Accepted: 02/02/2023] [Indexed: 06/18/2023]
Abstract
This study comprehensively investigates the quality of drinking water produced by novel advanced treatment encompassing 1 kDa hollow fiber nanofiltration (HFNF) - Biological Activated Carbon Filtration (BACF) from (reservoir) surface water, and compares this with drinking water after conventional 'CSF' pretreatment (coagulation - flocculation - sedimentation - media filtration - UV-disinfection) - BACF. The objective of HFNF - BACF treatment is to enhance the drinking water's quality in increased biological stability, reduced concentrations of organic micropollutants (OMP), and improvement in other chemical-physical parameters, whilst maintaining sufficient hardness to avoid subsequent remineralization. For this study a large suite of quality parameters was extensively monitored in pilot plants during nearly two years, enabling the incorporation of seasonal effects. HFNF - BACF treatment accomplished a similarly high level of biological stability as regrowth-free drinking waters (total organic carbon (DOC) 0.6 mg/L, assimilable organic carbon (AOC) 4 μg/L Ac-C and <1 μg/L biopolymer-C, total microbial growth potential (MGP) as BPC14 50 ng d/L and as BGP 170 × 103 cells/mL), unlike the conventional treatment (1.9 mg/L, 10 μg/L, 9 μg/L, 130 ng d/L and 170 × 103 cells/mL, respectively) where regrowth occurred in its distribution network. Average OMP removal, including perfluoro-alkyl substances (PFAS), by HFNF - BACF (54%) was higher than conventional treatment (37%). This improvement was mainly attributable to rejection in the HFNF membrane step, indicating that the DOC concentration after HFNF pretreatment was not yet sufficiently low to eliminate competitive adsorption and/or preloading in the BACF (confirmed by laboratory experiments). The advanced treatment also performed better in turbidity, particulates and most trace metals. Importantly, hardness retention by HFNF was only moderate, rendering remineralization unnecessary. Overall, this study demonstrates the superior performance in water quality of advanced HFNF - BACF treatment compared to conventional treatment.
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Affiliation(s)
- R Schurer
- Evides Water Company, PO Box 4472, 3006 AL, Rotterdam, the Netherlands; Department of Environmental Technology, Wageningen University, Bornse Weilanden 9, 6708 WG, Wageningen, the Netherlands; IHE Delft Institute for Water Education, Environmental Engineering and Water Technology Department, Westvest 7, 2611 AX, Delft, the Netherlands.
| | - D J de Ridder
- Evides Water Company, PO Box 4472, 3006 AL, Rotterdam, the Netherlands
| | - J C Schippers
- IHE Delft Institute for Water Education, Environmental Engineering and Water Technology Department, Westvest 7, 2611 AX, Delft, the Netherlands
| | - W A M Hijnen
- Evides Water Company, PO Box 4472, 3006 AL, Rotterdam, the Netherlands
| | - L Vredenbregt
- Pentair X-Flow, PO Box 741, 7500 AS, Enschede, the Netherlands
| | - A van der Wal
- Evides Water Company, PO Box 4472, 3006 AL, Rotterdam, the Netherlands; Department of Environmental Technology, Wageningen University, Bornse Weilanden 9, 6708 WG, Wageningen, the Netherlands
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Nitrogen-doped carbon nanotube modified ultrafiltration membrane activating peroxymonosulfate for catalytic transformation of phosphonate and mitigation of membrane fouling. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2023.123522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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7
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Lei C, Chen Y, Li A, Gao R, Zhang Z, Chen J, Shi P, Zhou Q, Ma Y. A new process to further remove dissolved organic matter and disinfection by-product formation potential during drinking water treatment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:20959-20969. [PMID: 36264461 DOI: 10.1007/s11356-022-23676-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 10/12/2022] [Indexed: 06/16/2023]
Abstract
Biological activated carbon (BAC) will produce soluble microbial products (SMPs), which affect effluent quality. To clarify the mechanism by which BAC affects effluent water quality, the processes of a drinking water plant in Jiangsu Province were investigated. It was found that during the O3-BAC process, although ozonation could remove dissolved organic matter (DOC) to a certain extent, the DOC increased from 4.44 to 4.47 mg/L after BAC. Dissolved organic matter (DOM) in effluent from different processes was divided into five fractions based on hydrophilicity and hydrophobicity by resin fractionation. Through fluorescence excitation-emission matrix (EEM) spectroscopy combined with DOC analysis, it was found that SMPs are mainly included in transitional hydrophilic neutral (TPIN) fraction, which was the main cause of the DOC increase. Therefore, a new combined process was designed to remove TPIN effectively by coagulation after biological treatment, and found that coagulation had a good removal rate (13.2%) on TPIN. The trihalomethane formation potential (THMFP) of TPIN could be reduced effectively by 44.9% after coagulation. Compared with the old process, the new combined process had a higher removal rate (14.2-30.0%) of DOC, as well as a greater reduction of THMFP (29.0-78.6%) and haloacetic acid formation potential (HAAFP) (46.4-75.3%). This study aims to reveal the mechanism by which SMPs affect effluent water quality and exacerbate health risks, and to propose a solution to provide theoretical support for the design and optimization of drinking water treatment processes.
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Affiliation(s)
- Chongtian Lei
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Yurong Chen
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Aimin Li
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Rui Gao
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Ziang Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Junxia Chen
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Peng Shi
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Qing Zhou
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Yan Ma
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China.
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8
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Mojela H, Gericke G, Madhav H, Malinga SP. Seasonal variations of natural organic matter (NOM) in surface water supplied to two coal-fired power stations. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:15454-15463. [PMID: 36169834 DOI: 10.1007/s11356-022-23239-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 09/20/2022] [Indexed: 06/16/2023]
Abstract
Global issues such as pollution and global warming have resulted in changes in water characteristics over the past 20 years. Natural organic matter (NOM) which is a major component in water systems has shown an increase globally. This increase in NOM concentration has negatively affected both water treatment processes and drinking water quality. It is subsequently critical to understand the seasonal variations and composition of NOM to be able to address issues related to NOM. In this study, techniques such as ultraviolet-visible spectroscopy, total organic carbon and liquid chromatography-organic carbon detection (LC-OCD) were used for characterisation and quantification of NOM. Two coal-fired power stations were selected for this study with each power station receiving water from a different source, i.e. power station A receives water from the Vaal River and power station B from the Nkomati River. Results from this study demonstrated that composition and concentration of NOM from these two water sources varied seasonally. Characterisation of NOM using the LC-OCD indicated that the different fractions of NOM, i.e. low molecular weight neutrals, low molecular weight acids, building blocks, humic substances and biopolymers, varied seasonally. The dissolved organic carbon concentration and specific ultraviolet absorbance values of the raw water at both power stations showed an increment amid the wet seasons and a decrease amid the dry seasons.
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Affiliation(s)
- Happiness Mojela
- Department of Chemical Sciences, University of Johannesburg, P.O. Box 17011, Doornfontein Campus, Johannesburg, 2028, South Africa
- Eskom RT&D, Private Bag X40175, Cleveland, Johannesburg, 2022, South Africa
| | - Gerhard Gericke
- Eskom RT&D, Private Bag X40175, Cleveland, Johannesburg, 2022, South Africa
| | - Heena Madhav
- Eskom RT&D, Private Bag X40175, Cleveland, Johannesburg, 2022, South Africa
| | - Soraya Phumzile Malinga
- Department of Chemical Sciences, University of Johannesburg, P.O. Box 17011, Doornfontein Campus, Johannesburg, 2028, South Africa.
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Stoffel D, Derlon N, Traber J, Staaks C, Heijnen M, Morgenroth E, Jacquin C. Gravity-driven membrane filtration with compact second-life modules daily backwashed: An alternative to conventional ultrafiltration for centralized facilities. WATER RESEARCH X 2023; 18:100178. [PMID: 37250288 PMCID: PMC10214304 DOI: 10.1016/j.wroa.2023.100178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Gravity-driven membrane (GDM) filtration is a strategic alternative to conventional ultrafiltration (UF) for the resilient production of drinking water via ultrafiltration when resources become scarce, given the low dependency on energy and chemicals, and longer membrane lifetime. Implementation at large scale requires the use of compact and low-cost membrane modules with high biopolymer removal capacity. We therefore evaluated (1) to what extent stable flux can be obtained with compact membrane modules, i.e., inside-out hollow fiber membranes, and frequent gravity-driven backwash, (2) whether we can reduce membrane expenses by effectively utilizing second-life UF modules, i.e., modules that have been discarded by treatment plant operators because they are no longer under warranty, (3) if biopolymer removal could be maintained when applying a frequent backwash and with second-life modules and (4) which GDM filtration scenarios are economically viable compared to conventional UF, when considering the influence of new or second-life modules, membrane lifetime, stable flux value and energy pricing. Our findings showed that it was possible to maintain stable fluxes around 10 L/m2/h with both new and second-life modules for 142 days, but a daily gravity-driven backwash was necessary and sufficient to compensate the continuous flux drop observed with compact modules. In addition, the backwash did not affect the biopolymer removal. Costs calculations revealed two significant findings: (1) using second-life modules made GDM filtration membrane investment less expensive than conventional UF, despite the higher module requirements for GDM filtration and (2) overall costs of GDM filtration with a gravity-driven backwash were unaffected by energy prices rise, while conventional UF costs rose significantly. The later increased the number of economically viable GDM filtration scenarios, including scenarios with new modules. In summary, we proposed an approach that could make GDM filtration in centralized facilities feasible and increase the range of UF operating conditions to better adapt to increasing environmental and societal constraints.
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Affiliation(s)
- Deborah Stoffel
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, Dübendorf 8600, Switzerland
| | - Nicolas Derlon
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, Dübendorf 8600, Switzerland
| | - Jacqueline Traber
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, Dübendorf 8600, Switzerland
| | | | | | - Eberhard Morgenroth
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, Dübendorf 8600, Switzerland
- ETH Zürich, Institute of Environmental Engineering, Zürich 8093, Switzerland
| | - Céline Jacquin
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, Dübendorf 8600, Switzerland
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Organic-inorganic composite ultrafiltration membrane with anti-fouling and catalytic properties by in-situ co-casting for water treatment. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2022.120984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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11
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Zhao J, Jiang W, Wang H, Zhang H, Wang J, Yang J, Lin D, Liang H. Ferrate-enhanced electrocoagulation/ultrafiltration system on municipal secondary effluent treatment: Identify synergistic contribution of coagulant and oxidation. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.121587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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12
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Hou C, Chen L, Dong Y, Yang Y, Zhang X. Unraveling dissolved organic matter in drinking water through integrated ozonation/ceramic membrane and biological activated carbon process using FT-ICR MS. WATER RESEARCH 2022; 222:118881. [PMID: 35907301 DOI: 10.1016/j.watres.2022.118881] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 07/16/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
The performance of an integrated process comprising coagulation, ozonation, and catalytic ceramic membrane filtration (CMF) followed by treatment with biological active carbon (BAC) was evaluated in a pilot-scale (96 m3/d) experiment to understand the biostability and quality of the finished water. The fate of dissolved organic matter (DOM) at the molecular level was explored using Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Biostable finished water with an assimilable organic carbon (AOC) concentration of 30.2-45.4 µg/L was obtained by the integrated process, and the high hydraulic retention time (HRT) (≥ 45 min) of the BAC filter was necessary to provide biostable finished water. The coagulation/O3/CMF unit efficiently transformed nitrogen-containing polyaromatic hydrocarbons (PAH) with aromaticity and large molecular weight (Mw) (500-1000 Da) into CHO-type highly unsaturated phenolic compounds (HuPh) with less aromaticity and medium Mw (300-500 Da), which were effectively removed by subsequent BAC filtering. The main reaction was oxygen addition, followed by deamination and dealkylation of the coagulation/O3/CMF unit and decarboxylation of the BAC filter. Principal component analysis revealed that N-containing and large-Mw PAH are potential AOC precursors, and the chemical characteristics of CHO-type and medium-Mw HuPh make them AOC candidates (correlation coefficients > 0.96). This study provides insights into the management of drinking water biostability and its suitability for the practical application of the integrated coagulation/O3/CMF-BAC process in drinking water treatment plants.
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Affiliation(s)
- Congyu Hou
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, Guangdong 518055, China; School of Environment, Tsinghua University, Beijing 100084, China
| | - Li Chen
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, Guangdong 518055, China; School of Environment, Tsinghua University, Beijing 100084, China.
| | - Yawen Dong
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, Guangdong 518055, China; School of Environment, Tsinghua University, Beijing 100084, China
| | - Yulong Yang
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, Guangdong 518055, China; School of Environment, Tsinghua University, Beijing 100084, China
| | - Xihui Zhang
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, Guangdong 518055, China; School of Environment, Tsinghua University, Beijing 100084, China.
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13
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Lin H, Hu Y. Impact of different source-water switching patterns on the stability of drinking water in an estuarine urban water distribution system. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:49059-49069. [PMID: 35217958 DOI: 10.1007/s11356-022-19117-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 02/03/2022] [Indexed: 06/14/2023]
Abstract
Source-water switching can lead to instability in drinking water distribution systems. In estuarine cities using surface water as source water where salt tide occasionally happens, the influence can be particularly complex due to changes of Larson Index (LI). The objective of this study was to investigate the effects of different switching patterns on the stability of water in an estuarine city. Fluctuated LI was found in the current distribution system. LI of the new source water was lower and more stable. Susceptible areas with a high frequency of over standard water quality were identified and pipe scales there were mainly composed of relatively stable iron oxides with dense crystal structures (Fe3O4 and α-FeOOH). Two old pipe sections were used to simulate different switching patterns. The microbial risk did not increase significantly when the original and new water sources were combined in different ratios (2∶8, 5∶5), when multiple water sources were used (3∶3∶4) or when salinity increased. The better water quality, lower LI of the new source water, and stability of the current distribution system together contributed to the biostability. Total iron increased after switching, then declined and stabilized for most switching patterns. Salt tide can lead to sharp iron release. The results provided insightful information for distribution systems that have cast iron pipes and that might encounter source-water switching patterns.
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Affiliation(s)
- Huirong Lin
- Department of Environmental Science and Engineering, College of Chemical Engineering, Huaqiao University, 668 Jimei Road, Xiamen, 361021, Fujian, China.
| | - Yue Hu
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China
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14
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Boivin S, Tanabe S, Fujioka T. Online evaluation of bacterial cells in sand filter effluents during full-scale treatment of drinking water. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 814:152508. [PMID: 34968596 DOI: 10.1016/j.scitotenv.2021.152508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 12/13/2021] [Accepted: 12/14/2021] [Indexed: 06/14/2023]
Abstract
Ensuring the microbiological safety of drinking water is critical to protect public health. This study aimed to evaluate the reliability of real-time bacteriological counter coupled with an online dialysis membrane-based pre-treatment system for continuously monitoring bacterial cell counts in sand filter effluents of a full-scale drinking water treatment plant. The pre-treatment system, which included anion exchange resins (porous polymeric microbeads that trap ions for releasing other ions) for dialysate regeneration, successfully achieved the stable attenuation of background interfering substances (humic acids) during the 19-d test. The real-time bacteriological counter equipped with the pre-treatment system provided a continuous profile of bacterial cell counts in the sand filter effluent (0.2-2.5 × 104 counts/mL). The online analysis identified different timing of concentration peaks between particle and bacterial cell counts after backwashing. Bacterial community analysis revealed that Proteobacteria, Planctomycetes, and Cyanobacteria were the dominating phyla. Further, total bacterial cell counts determined by fluorescence microscopy and SYBR® Green I staining, a commonly accepted parameter, was found to be an indicator of online-monitored bacterial cell counts. The results indicated the potential of monitoring the bacterial cell counts in a sand filter process for providing an early warning of filter failures, which can allow plant operators to diagnose the overall system and provide countermeasures.
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Affiliation(s)
- Sandrine Boivin
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Shuji Tanabe
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Takahiro Fujioka
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
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15
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Chang H, Yu H, Li X, Zhou Z, Liang H, Song W, Ji H, Liang Y, Vidic RD. Role of biological granular activated carbon in contaminant removal and ultrafiltration membrane performance in a full-scale system. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2021.120122] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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16
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Schurer R, Hijnen WAM, van der Wal A. The significance of the biomass subfraction of high-MW organic carbon for the microbial growth and maintenance potential of disinfectant-free drinking water produced from surface water. WATER RESEARCH 2022; 209:117898. [PMID: 34896810 DOI: 10.1016/j.watres.2021.117898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 11/15/2021] [Accepted: 11/23/2021] [Indexed: 06/14/2023]
Abstract
Drinking water must be sufficiently biostable to avoid excessive microbial and invertebrate growth in disinfectant-free distribution systems. The production of biologically stable drinking water is challenging for conventional surface water treatment plants using reservoirs as feed water due to the presence of slowly biodegradable particulate and high-molecular weight biopolymeric organic carbon (high-MW OC) which increases the Microbial Growth Potential (MGP) in the feed water and produced drinking water. The study presented here provides new insights in the relationship between high-MW OC and MGP for a full-scale surface water treatment plant. Controlled-conditions addition series experiments showed that MGP increases linearly with the high-MW OC concentration with a seasonally variable ratio. Laboratory filtration indicated that MGP is mainly attributable to the high-MW OC subfraction of > 0.12 µm particle size coinciding with microbial biomass. Intensive field monitoring revealed clear seasonal patterns in the plant's feed water and treated water levels of high-MW OC, biomass and MGP. These parameters reach maximum levels in the periods of high water temperature with the notable exception of the treated water's high-MW OC concentration which exhibits an opposite seasonal pattern (reflecting seasonally variable removal in the treatment). Moreover, the field monitoring showed that MGP correlates well with the concentrations of biodegradable biopolymeric OC and with microbial biomass measured as ATP (adenosine triphosphate) and cell counts, but not with the total high-MW OC concentration in the treated water. Theoretical estimations showed that the OC quantities present in and consumed by the microbial biomass are in the same order of magnitude as slowly biodegradable biopolymers. From these results it is concluded that specifically the microbial biomass-associated and biodegradable biopolymeric OC subfraction of the totally present high-MW OC is important for MGP. Finally, the MGP-assay results and theoretical calculations showed for the high-MW OC matrix that the microbial biomass' OC consumption for maintenance is significant vis-á-vis that for growth, and that stable and high levels of biomass are sustained in the treated water which may adversely affect biological stability in the distribution network.
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Affiliation(s)
- R Schurer
- Evides Water Company, PO Box 4472, 3006 AL Rotterdam, the Netherlands; Department of Environmental Technology, Wageningen University, Bornse Weilanden 9, 6708 WG Wageningen, the Netherlands; IHE Delft Institute for Water Education, Environmental Engineering and Water Technology Department, Westvest 7, 2611 AX Delft, the Netherlands.
| | - W A M Hijnen
- Evides Water Company, PO Box 4472, 3006 AL Rotterdam, the Netherlands; KWR Watercycle Research Institute, P.O. Box 1072, 3430 BB, Nieuwegein, the Netherlands
| | - A van der Wal
- Evides Water Company, PO Box 4472, 3006 AL Rotterdam, the Netherlands; Department of Environmental Technology, Wageningen University, Bornse Weilanden 9, 6708 WG Wageningen, the Netherlands
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17
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Moyo W, Motsa MM, Chaukura N, Msagati TAM, Mamba BB, Heijman SGJ, Nkambule TTI. Characterization of natural organic matter in South African drinking water treatment plants: Towards integrating ceramic membrane filtration. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2022; 94:e10693. [PMID: 35199396 DOI: 10.1002/wer.10693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 01/20/2022] [Accepted: 01/22/2022] [Indexed: 06/14/2023]
Abstract
This work presents the first comprehensive investigation of natural organic matter (NOM) fraction removal using ceramic membranes in South Africa. The rate of removal of bulk NOM (measured as UV254 and DOC % removal), the biodegradable dissolved organic carbon (BDOC) fraction, polarity-based fractions, and fluorescent dissolved organic carbon (FDOM) fractions was investigated from water abstracted from drinking water treatment plants (WTPs) in South Africa. Further, mechanisms of ceramic membrane fouling by waters of South Africa were studied. Ceramic membranes removed more than 80% DOC from samples from coastal WTPs, whereas for inland plants, the removal was between 60% and 75% of DOC. FDOM was removed to at least 80% regardless of the site of the plant. The BDOC removal by the ceramic membranes was above 85%. The hydrophobic fraction was the most amenable to removal by ceramic membranes regardless of the site of sample abstraction (above 60% for all sites). The freshness index (β:α) correlated strongly to UV254 removal (R2 = 0.96), thus UV254 removal can serve as a proxy for the susceptibility to removal of such class of NOM by ceramic membranes. This investigation demonstrated that ceramic membranes could be a valuable technology if integrated into the existing WTPs. PRACTITIONER POINTS: The removal of bulk parameters by ceramic membrane was greater than unit conventional processes used in all the sampled water treatment plants. The hydrophobic polarity-based fraction of NOM was the most amenable to removal by ceramic membranes regardless of the site of the WTP. Polarity-based fractions, aromaticity, and initial DOC had a combined influence on the removal of organic matter by ceramic membranes as explained by principal component three.
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Affiliation(s)
- Welldone Moyo
- Institute for Nanotechnology and Water Sustainability, University of South Africa (UNISA), Johannesburg, South Africa
| | - Machawe M Motsa
- Institute for Nanotechnology and Water Sustainability, University of South Africa (UNISA), Johannesburg, South Africa
| | - Nhamo Chaukura
- Institute for Nanotechnology and Water Sustainability, University of South Africa (UNISA), Johannesburg, South Africa
- Department of Physical and Earth Sciences, Sol Plaatje University, Kimberley, South Africa
| | - Titus A M Msagati
- Institute for Nanotechnology and Water Sustainability, University of South Africa (UNISA), Johannesburg, South Africa
| | - Bhekie B Mamba
- Institute for Nanotechnology and Water Sustainability, University of South Africa (UNISA), Johannesburg, South Africa
| | - Sebastiaan G J Heijman
- Department of Civil Engineering and GeoSciences, Technical University of Delft, Delft, The Netherlands
| | - Thabo T I Nkambule
- Institute for Nanotechnology and Water Sustainability, University of South Africa (UNISA), Johannesburg, South Africa
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18
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Duong TH, Bang WH, Kim GB, Maeng SK. Lab experiments on hybridization of managed aquifer recharge with river water via sand column, pre-oxidation, and nanofiltration. CHEMOSPHERE 2022; 287:132350. [PMID: 34582933 DOI: 10.1016/j.chemosphere.2021.132350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 09/21/2021] [Accepted: 09/22/2021] [Indexed: 06/13/2023]
Abstract
A hybridization of managed aquifer recharge (MAR) with pre-oxidation processes was conducted in this study to investigate changes in dissolved organic matter characteristics and the attenuation of selected trace organic contaminants (TrOCs). Potassium permanganate, chlorine, and ozone treatments were used for pre-oxidation, which effectively attenuated some TrOCs, particularly the combination of MAR with ozone achieved 84-99% attenuation. The pre-oxidation step using potassium permanganate showed high removal of carbamazepine (96%). Moreover, MAR was also combined with nanofiltration (NF) as a multi-barrier concept for the removal of persistent TrOCs after MAR. A short-chain polyfluoroalkyl substance (PFAS) was effectively removed after combining MAR columns with NF membranes. Thus, pre-oxidation coupled with MAR followed by NF could potentially enhance the removal of selected TrOCs.
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Affiliation(s)
- Thi Huyen Duong
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Republic of Korea
| | - Woo Hyuck Bang
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Republic of Korea
| | - Gyoo-Bum Kim
- Department of Construction Safety and Disaster Prevention, Daejeon University, 62 Daehak-ro, Dong-gu, Daejeon, 300-716, Republic of Korea
| | - Sung Kyu Maeng
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Republic of Korea.
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19
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Role of different dimensional carbon nanoparticles in catalytic oxidation of organic pollutants and alleviating membrane fouling during ultrafiltration of surface water. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.118804] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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20
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Duong TH, Park JW, Maeng SK. Assessment of organic carbon migration and biofilm formation potential on polymeric tubes in contact with water. JOURNAL OF HAZARDOUS MATERIALS 2021; 411:125095. [PMID: 33858087 DOI: 10.1016/j.jhazmat.2021.125095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 12/31/2020] [Accepted: 01/07/2021] [Indexed: 06/12/2023]
Abstract
Biofilm formation has been frequently identified as a pathway of nosocomial infection in polymeric tubes used for patients of all ages. Biofilm formation on tube surfaces can lead to hygienic failure and cause diarrhea, stomach pain, inflammation, and digestive system disease. This study investigated the influence of polymeric tube materials in contact with water on the biomass formation potential and migration potential of microbially available carbon from plasticizers using a BioMig test. The thermoplastic elastomer tube, which is reusable, leached a relatively low amount of assimilable organic carbon to water. In contrast, the assimilable organic carbon migration potential of polyurethane was the most significant, 6-fold greater than that of the thermoplastic elastomer. Moreover, the same materials (e.g., silicone) produced via different manufacturing processes showed significant differences in migration behaviors. The potential biomass formation observed in polyurethane was approximately 7 × 109 cells cm-2 for both Aeromonas hydrophila and Escherichia coli strains. This study highlights the importance of choosing the correct material characteristics of polymeric tubes in contact with water to protect them from bacterial contamination. Therefore, manufacturers can use the BioMig test to evaluate and produce more hygienic and biostable tubes.
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Affiliation(s)
- Thi Huyen Duong
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Republic of Korea
| | - Ji Won Park
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Republic of Korea
| | - Sung Kyu Maeng
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Republic of Korea.
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21
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Li Y, Zhang L, Yang L, Zhang Y, Niu Z. Hydrolysis characteristics and risk assessment of a widely detected emerging drinking water disinfection-by-product-2,6-dichloro-1,4-benzoquinone-in the water environment of Tianjin (China). THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 765:144394. [PMID: 33418327 DOI: 10.1016/j.scitotenv.2020.144394] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 11/29/2020] [Accepted: 12/01/2020] [Indexed: 06/12/2023]
Abstract
Halobenzoquinones (HBQs) are an emerging class of drinking water disinfection byproducts (DBPs) that have been frequently detected in drinking water and are highly relevant to bladder cancer. Among the studied HBQs, 2,6-dichloro-1,4-benzoquinone (DCBQ) had the highest detection frequency and concentrations in drinking water. However, compared to other countries, the studies on HBQs that are being conducted in China, especially those on HBQs in drinking water, are not sufficient. Therefore, the concentrations of DCBQ in the Tianjin drinking water supply system were investigated in two seasons (winter and summer), and the risk that is posed by DCBQ in drinking water was evaluated for the first time. In addition, since HBQs are prone to hydrolysis in neutral and alkaline environments, identification of the hydrolytic characteristics of DCBQ at various pH values and in the real water environment is essential for better describing the environmental behavior of DCBQ; hence, the hydrolysis characteristics of DCBQ in phosphate buffers with various pH values and in four water samples were also examined in our study. The results demonstrated that DCBQ was widely detected in the drinking water treatment process and distribution systems, and the average concentration in our study (12.0 ng/L) was at a moderately high level compared with the reported concentration of DCBQ in the drinking water distribution networks. The risk quotient (RQ) of DCBQ is equivalent to that of trihalomethanes (THMs); thus, the relatively low concentrations of DCBQ should also be considered. Furthermore, the results demonstrated that the hydrolysis of DCBQ follows first-order reaction kinetics, the reaction rate accelerates as the pH of the phosphate buffer system increases, and the rate of hydrolysis of DCBQ in drinking water is affected not only by the pH but also by other environmental factors, such as the organic matter concentration. Therefore, further investigation is necessary to identify the main factor of DCBQ hydrolysis in real water environments.
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Affiliation(s)
- Yuna Li
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Lifen Zhang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria / Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Lumin Yang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria / Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Ying Zhang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria / Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
| | - Zhiguang Niu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
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22
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Tang A, Bi X, Li X, Li F, Liao X, Zou J, Sun W, Yuan B. The inactivation of bacteriophage MS2 by sodium hypochlorite in the presence of particles. CHEMOSPHERE 2021; 266:129191. [PMID: 33310358 DOI: 10.1016/j.chemosphere.2020.129191] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 11/20/2020] [Accepted: 12/01/2020] [Indexed: 06/12/2023]
Abstract
The inactivation of bacteriophage MS2 by sodium hypochlorite was investigated to understand the effect of solution chemistry on the disinfection efficacy in the presence of particles. Kaolinite and Microcystis aeruginosa (M. aeruginosa) were used as the models of inorganic and organic particles to simulate high turbidity and algal cells, respectively, in drinking water sources. In both particle-containing solutions, lower pH, the presence of cations (di-valent Ca2+) and natural organic matters (NOM) were regarded as the main factors to influence the aggregation and inactivation of MS2. The results showed that MS2 aggregated in all solutions at pH 3.0, protecting the inner viruses. At pH 7.0, the presence of Na+ cations (0-200 mmol/L) did not affect the inactivation efficacy of MS2, which always followed the order of particles-free ≈ kaolinite > M. aeruginosa. The inactivation efficacy of MS2 in the presence of Ca2+ cations followed the order of kaolinite > particles-free > M. aeruginosa at 0-50 mmol/L Ca2+ cations, while the inactivation efficacy remained almost constant in the range of 100-200 mmol/L Ca2+ cations. By contrast, kaolinite offered not enough protection to adsorbed MS2, but MS2 aggregation decreased disinfection efficacy at a high concentration of Ca2+ cations. Moreover, the presence of humic acid as NOM decreased the inactivation of MS2 more significantly than M. aeruginosa due to the more consumption of free chlorine from humic acids. Therefore, the co-existence of NOM and di-valent Ca2+ cations are potential challenges for the inactivation of viruses by sodium hypochlorite in safe drinking water.
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Affiliation(s)
- Aixi Tang
- Xiamen Engineering & Technology Research Center for Urban Water Environment Planning and Remediation, College of Civil Engineering, Huaqiao University, Xiamen, Fujian, 361021, PR China
| | - Xiaochao Bi
- Xiamen Engineering & Technology Research Center for Urban Water Environment Planning and Remediation, College of Civil Engineering, Huaqiao University, Xiamen, Fujian, 361021, PR China
| | - Xiaoxue Li
- Xiamen Engineering & Technology Research Center for Urban Water Environment Planning and Remediation, College of Civil Engineering, Huaqiao University, Xiamen, Fujian, 361021, PR China
| | - Fei Li
- Xiamen Engineering & Technology Research Center for Urban Water Environment Planning and Remediation, College of Civil Engineering, Huaqiao University, Xiamen, Fujian, 361021, PR China
| | - Xiaobin Liao
- Xiamen Engineering & Technology Research Center for Urban Water Environment Planning and Remediation, College of Civil Engineering, Huaqiao University, Xiamen, Fujian, 361021, PR China
| | - Jing Zou
- Xiamen Engineering & Technology Research Center for Urban Water Environment Planning and Remediation, College of Civil Engineering, Huaqiao University, Xiamen, Fujian, 361021, PR China
| | - Wenjie Sun
- Department of Civil and Environmental Engineering, Southern Methodist University, Dallas, TX, 75275, USA
| | - Baoling Yuan
- Xiamen Engineering & Technology Research Center for Urban Water Environment Planning and Remediation, College of Civil Engineering, Huaqiao University, Xiamen, Fujian, 361021, PR China.
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23
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Zhang H, Xu L, Huang T, Yan M, Liu K, Miao Y, He H, Li S, Sekar R. Combined effects of seasonality and stagnation on tap water quality: Changes in chemical parameters, metabolic activity and co-existence in bacterial community. JOURNAL OF HAZARDOUS MATERIALS 2021; 403:124018. [PMID: 33265044 DOI: 10.1016/j.jhazmat.2020.124018] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 08/17/2020] [Accepted: 09/13/2020] [Indexed: 06/12/2023]
Abstract
In drinking water distribution pipeline systems, the tap water quality is regulated by several biotic and abiotic factors, which can threaten the health of consumers. Stagnation is inevitable in the water distribution pipeline however, the combined effects of seasonal changes and stagnation on tap water quality are not well understood. Here, we investigated the seasonal variations in the chemical and biological quality of water after overnight stagnation for a period of one year. The results showed that the tap water quality deteriorated after overnight stagnation, with up to a 2.7-fold increase in the total iron concentrations. The total bacterial cell concentrations increased by 59-231% after overnight stagnation. The total cell and cell-bound adenosine triphosphate (ATP) of the stagnant water samples peaked in summer. In addition, Biolog analysis showed that the metabolic activities of microbes were higher in spring. The bacterial community based on Illumina Miseq DNA sequence analysis found that Proteobacteria dominated the drinking water bacterial community. The bacterial community structure varied significantly among different seasons, where the diversity and richness of the community were much higher in spring. Structural equation modeling (SEM) was constructed to determine the correlations between bacterial metabolic functions and the community structure. The redundancy analysis (RDA) indicated that the residual chlorine played a critical role in the construction of the bacterial community. Altogether, the overall findings from the present work provide novel insights into how the quality of tap water quality impacted by the seasonal changes and overnight stagnation.
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Affiliation(s)
- Haihan Zhang
- Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Lei Xu
- Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Tinglin Huang
- Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Miaomiao Yan
- Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Kaiwen Liu
- Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Yutian Miao
- Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Huiyan He
- Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Sulin Li
- Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Raju Sekar
- Department of Biological Sciences, Xi'an Jiaotong-Liverpool University, Suzhou 215123, China
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24
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Yu H, Li X, Chang H, Zhou Z, Zhang T, Yang Y, Li G, Ji H, Cai C, Liang H. Performance of hollow fiber ultrafiltration membrane in a full-scale drinking water treatment plant in China: A systematic evaluation during 7-year operation. J Memb Sci 2020. [DOI: 10.1016/j.memsci.2020.118469] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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25
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Shen Z, Wang Y, Chen W, Xu H, Zhang L, Lin C, Lin T, Tao H, Mei C, Lu C. Investigation of nitrogen pollutants transformation and its pathways along the long-distance prechlorinated raw water distribution system. CHEMOSPHERE 2020; 255:126833. [PMID: 32387724 DOI: 10.1016/j.chemosphere.2020.126833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 04/11/2020] [Accepted: 04/16/2020] [Indexed: 06/11/2023]
Abstract
Understanding the transformation pattern of nitrogen (N) pollutants and its pathways in the prechlorinated raw water distribution system (PRWDS) is vital for controlling the stablitiy and safety of raw water qulity. This study investigated the N transformation, N functional genes and their correlations to find the N transformation pathways along the PRWDS. Results suggested that simultaneous nitrification, anaerobic ammonium oxidation and denitrification (SNAD) contribute to the N transformationin the PRWDS. Along the pipeline, anammox 16S rRNA (9.18 × 107-8.41 × 108 copies/g), limited by prechlorination, was the most abundant N functional genes and anammox process was the main pathway of ammonia nitrogen (NH4+-N). The decreasing NH4+-N was connected with Planctomycetes, Nitrospira and abundance of nxrA attributing to the joint effort of anammox and declined nitrification. The concentration of nitrate (NO3--N) increasing at first and then decreasing, was correlated positively with Sphingomonas. because of the declined nitritication and increased denitrification. Besides, the NO3--N→NO2--N process was considered to be primary NO3--N transformation pathways. Increases in the concentration of dissolved organic nitrogen (DON) and nitrite (NO2--N) observed in the PRWDS had positive correlation with relative abundance of Pseudomonas. We believe that prechlorination shaped the particular bacterialcharacteristics in biofilms and influenced the N transformation pathways indirectly, resulting in the varying N transformation rules in PRWDSs. Moreover, systematic and extended research is particularly vital for determining the effects of changes in source water quality and environmental conditions on bacterial community structure and N conversion along PRWDSs.
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Affiliation(s)
- Zhen Shen
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, No.1 Xikang Road, Nanjing, 210098, China; Wanjiang University of Technology, Maanshan, 243031, China.
| | - Yueting Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, No.1 Xikang Road, Nanjing, 210098, China.
| | - Wei Chen
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, No.1 Xikang Road, Nanjing, 210098, China.
| | - Hang Xu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, No.1 Xikang Road, Nanjing, 210098, China.
| | - Lei Zhang
- College of Civil and Architechure Engineering, Chuzhou University, 1 West Huifeng Road, Chuzhou, 239000, China.
| | - Chenshuo Lin
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, No.1 Xikang Road, Nanjing, 210098, China.
| | - Tao Lin
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, No.1 Xikang Road, Nanjing, 210098, China.
| | - Hui Tao
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, No.1 Xikang Road, Nanjing, 210098, China.
| | - Caihua Mei
- College of Civil and Architechure Engineering, Chuzhou University, 1 West Huifeng Road, Chuzhou, 239000, China.
| | - Chunhui Lu
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, China.
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26
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Activation of peroxymonosulfate by metal oxide nanoparticles for mitigating organic membrane fouling in surface water treatment. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.116935] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Pre-deposition layers for alleviating ultrafiltration membrane fouling by organic matter: Role of hexagonally and cubically ordered mesoporous carbons. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.116599] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Sousi M, Salinas-Rodriguez SG, Liu G, Schippers JC, Kennedy MD, van der Meer W. Measuring Bacterial Growth Potential of Ultra-Low Nutrient Drinking Water Produced by Reverse Osmosis: Effect of Sample Pre-treatment and Bacterial Inoculum. Front Microbiol 2020; 11:791. [PMID: 32411118 PMCID: PMC7201026 DOI: 10.3389/fmicb.2020.00791] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 04/02/2020] [Indexed: 12/20/2022] Open
Abstract
Measuring bacterial growth potential (BGP) involves sample pre-treatment and inoculation, both of which may introduce contaminants in ultra-low nutrient water (e.g., remineralized RO permeate). Pasteurization pre-treatment may lead to denaturing of nutrients, and membrane filtration may leach/remove nutrients into/from water samples. Inoculating remineralized RO permeate samples with natural bacteria from conventional drinking water leads to undesired nutrient addition, which could be avoided by using the remineralized RO permeate itself as inoculum. Therefore, this study examined the effect of pasteurization and membrane filtration on the BGP of remineralized RO permeate. In addition, the possibility of using bacteria from remineralized RO permeate as inoculum was investigated by evaluating their ability to utilize organic carbon that is readily available (acetate, glucose) or complex (laminarin, gelatin, and natural dissolved organic carbon), as compared with bacteria from conventional drinking water. The results showed that membrane filtration pre-treatment increased (140-320%) the BGP of remineralized RO permeate despite the extensive soaking and flushing of filters (>350 h), whereas no effect was observed on the BGP of conventional drinking water owing to its high nutrient content. Pasteurization pre-treatment had insignificant effects on the BGP of both water types. Remineralized RO permeate bacteria showed limitations in utilizing complex organic carbon compared with bacteria from conventional drinking water. In conclusion, the BGP bioassay for ultra-low nutrient water (e.g., remineralized RO permeate) should consider pasteurization pre-treatment. However, an inoculum comprising bacteria from remineralized RO permeate is not recommended as the bacterial consortium was shown to be limited in terms of the compounds they could utilize for growth.
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Affiliation(s)
- Mohaned Sousi
- Department of Environmental Engineering and Water Technology, IHE Delft Institute for Water Education, Delft, Netherlands
- Faculty of Science and Technology, University of Twente, Enschede, Netherlands
| | - Sergio G. Salinas-Rodriguez
- Department of Environmental Engineering and Water Technology, IHE Delft Institute for Water Education, Delft, Netherlands
| | - Gang Liu
- Key Laboratory of Drinking Water Science and Technology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
- Department of Water Management, Faculty of Civil Engineering and Geoscience, Delft University of Technology, Delft, Netherlands
| | - Jan C. Schippers
- Department of Environmental Engineering and Water Technology, IHE Delft Institute for Water Education, Delft, Netherlands
| | - Maria D. Kennedy
- Department of Environmental Engineering and Water Technology, IHE Delft Institute for Water Education, Delft, Netherlands
- Department of Water Management, Faculty of Civil Engineering and Geoscience, Delft University of Technology, Delft, Netherlands
| | - Walter van der Meer
- Faculty of Science and Technology, University of Twente, Enschede, Netherlands
- Oasen Drinkwater, Gouda, Netherlands
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29
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Noh JH, Yoo SH, Son H, Fish KE, Douterelo I, Maeng SK. Effects of phosphate and hydrogen peroxide on the performance of a biological activated carbon filter for enhanced biofiltration. JOURNAL OF HAZARDOUS MATERIALS 2020; 388:121778. [PMID: 31818662 DOI: 10.1016/j.jhazmat.2019.121778] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 10/18/2019] [Accepted: 11/27/2019] [Indexed: 06/10/2023]
Abstract
Biofilm formation on biofilters can influence their hydraulic performance, thereby leading to head loss and an increase in energy use and costs for water utilities. The effects of a range of factors, including hydrogen peroxide and phosphate, on the performance of biological activated carbon (BAC) and biofilm formation were investigated using laboratory-scale columns. Head loss, total carbohydrates, and proteins were reduced in the nutrient-enhanced, oxidant-enhanced, and nutrient + oxidant-enhanced BAC filters. However, there were no changes in the removal of dissolved organic matter, trihalomethane formation potential, or selected trace organic contaminants. The biofilm formation on polyvinyl chloride and stainless steel coupons using the laboratory biofilm reactor system was lower when the effluent from a nutrient-enhanced column was used, which indicated that there was less biofilm formation in the distribution systems. This may have been because the effluent from the nutrient-enhanced column was more biologically stable. Therefore, enhanced biofiltration could be used not only to reduce head loss in biofilters, but also to delay biofilm formation in distribution systems.
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Affiliation(s)
- Jin Hyung Noh
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdongro, Gwangjin-gu, Seoul, 05006, Republic of Korea
| | - Song Hee Yoo
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdongro, Gwangjin-gu, Seoul, 05006, Republic of Korea
| | - Heejong Son
- Busan Water Quality Institute, Busan Water Authority, Busan, 50804, Republic of Korea
| | - Katherine E Fish
- Pennine Water Group, Department of Civil and Structural Engineering, The University of Sheffield, Sheffield, S1 3JD, United Kingdom
| | - Isabel Douterelo
- Pennine Water Group, Department of Civil and Structural Engineering, The University of Sheffield, Sheffield, S1 3JD, United Kingdom
| | - Sung Kyu Maeng
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdongro, Gwangjin-gu, Seoul, 05006, Republic of Korea.
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30
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Yang Y, Lohwacharin J, Takizawa S, Hou LA. Comparison between ferrihydrite adsorption and full-scale advanced drinking water treatment processes for controlling bacterial regrowth potential. CHEMOSPHERE 2020; 241:125001. [PMID: 31590020 DOI: 10.1016/j.chemosphere.2019.125001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 09/23/2019] [Accepted: 09/27/2019] [Indexed: 06/10/2023]
Abstract
Bacterial regrowth in drinking water systems is a threat to public health. In this study, ferrihydrite (Fh) adsorption was compared with advanced drinking water treatment processes (ADWTP) during one and a half years of sampling to test the reduction in assimilable organic carbon (AOC) and bacterial regrowth potential (BRP). Dissolved organic matter (DOM) was removed by Fh through ligand exchange and electrostatic interaction. The DOM removal was higher below pH 6 due to protonation of Fh surfaces. The ADWTP exhibited higher removal rates of DOM than Fh and lower phosphate removal rates than Fh. Excitation-emission matrix (EEM) and size exclusion chromatography (SEC) revealed that Fh removed aromatic DOM larger than 1000 Da, while the biological activated carbon (BAC) of ADWTP could remove DOM smaller than 1000 Da. These differences of organic compositions resulted in the lowest AOC of BAC treated water, and the lowest BRP of Fh-treated water, indicating that it was the most biostable water. Phosphate addition experiments illustrated that phosphorus was the primary rate limiting nutrient, indicating that the higher phosphate removal of Fh made it possible to produce waters with lower BRP than ADWTP. Therefore, BRP is considered to be a better indicator of bacterial regrowth than AOC when phosphorus is a rate-limiting nutrient, as is the case with the Fh treatment.
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Affiliation(s)
- Yu Yang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University. No.19, Xinjiekouwai Street, Haidian District, Beijing, 100875, China.
| | - Jenyuk Lohwacharin
- Department of Environmental Engineering, Chulalongkorn University, 254 Phayathai Road, Wangmai, Pathumwan, Bangkok 10330, Thailand.
| | - Satoshi Takizawa
- Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
| | - Li-An Hou
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University. No.19, Xinjiekouwai Street, Haidian District, Beijing, 100875, China; Xi' an High-Tech Institute, Xi' an, 710025, China.
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31
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Fujioka T, Yoshikawa H, Eguchi M, Boivin S, Kodamatani H. Application of stabilized hypobromite for controlling membrane fouling and N-nitrosodimethylamine formation. CHEMOSPHERE 2020; 240:124939. [PMID: 31726604 DOI: 10.1016/j.chemosphere.2019.124939] [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: 08/06/2019] [Revised: 09/19/2019] [Accepted: 09/21/2019] [Indexed: 06/10/2023]
Abstract
Chloramination is a conventional and successful pre-disinfection approach to control biological fouling for reverse osmosis (RO) treatment in water reuse. This study aimed to evaluate the possibility of using a new disinfectant-stabilized hypobromite-in controlling membrane fouling and the formation of a particular carcinogenic disinfection byproduct (DBP)-N-nitrosodimethylamine (NDMA). Our accelerated chemical exposure tests showed that the new disinfectant reduced the permeability of a polyamide RO membrane permeability from 6.7 to 4.1 L/m2hbar; however, its treatment impact was equivalent to that of chloramine. The disinfection efficacy of stabilized hypobromite was greater than that of chloramine when evaluated with intact bacterial counts, which suggests its potential for mitigating membrane biofouling. Additional pilot-scale tests using synthetic wastewater demonstrated that pre-disinfection with the use of stabilized hypobromite inhibits membrane fouling. Among 13 halogenated DBPs evaluated, the formation of bromoform by stabilized hypobromite was higher than that by chloramine at a high dose of 10 mg/L, thus suggesting the need for optimizing chemical doses for achieving sufficient biofouling mitigation. NDMA formation upon stabilized hypobromite treatment in two different types of actual treated wastewaters was found to be negligible and considerably lower than that by chloramine treatment. In addition, NDMA formation potential by stabilized hypobromite was 2-5 orders of magnitude lower than that by chloramine. Our findings suggest the potential of using stabilized hypobromite for controlling NDMA formation and biofouling, which are the keys to successful potable water reuse.
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Affiliation(s)
- Takahiro Fujioka
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, 852-8521, Japan.
| | - Hiro Yoshikawa
- R&D Center, Organo Corporation, 4-4-1 Nishionuma Minamiku, Sagamihara, 252-0332, Japan
| | - Masahiro Eguchi
- R&D Center, Organo Corporation, 4-4-1 Nishionuma Minamiku, Sagamihara, 252-0332, Japan
| | - Sandrine Boivin
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, 852-8521, Japan
| | - Hitoshi Kodamatani
- Division of Earth and Environmental Science, Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Korimoto, Kagoshima, 890-0065, Japan
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32
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Park JW, Park KY, Na Y, Park S, Kim S, Kweon JH, Maeng SK. Evaluation of organic migration and biomass formation on polymeric components in a point-of-use water dispenser. WATER RESEARCH 2019; 165:115025. [PMID: 31472335 DOI: 10.1016/j.watres.2019.115025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 08/18/2019] [Accepted: 08/22/2019] [Indexed: 06/10/2023]
Abstract
To minimize the aesthetic and hygienic concerns regarding tap water (e.g., odor, taste, suspended solids, and microorganisms), point-of-use (POU) water dispensers and filters are used in households worldwide. However, the POU water dispenser itself can adversely impact water quality. This study investigated the bacterial growth through a POU water dispenser fed with chlorinated tap water; specifically, the heterotrophic plate count increased from 0.01 to 20.01 × 103 of colony-forming units per ml. The BioMig test, which evaluates the biostability of polymeric materials based on the migration potential and the biofilm formation potential, was firstly applied for the water dispenser system. Organic migration and biofilm formation varied by the polymer type used in the water dispenser components (e.g., tubing, fittings, and reservoir). Assimilable organic carbon migration in cold water (23 ± 2 °C) was better correlated with the biofilm formation potential (R = 0.93) than that of warm water (60 ± 2 °C) migration (R = 0.62). The most problematic test material was silicone based on assimilable organic carbon migration and biofilm formation, whereas approved materials such as polyethylene and polyvinyl chloride were relatively stable. Polymeric component examination of an actual POU water dispenser revealed highly accumulated biofilms on the silicone tube used in the device (118 × 103 CFU cm-2). The use of polymers with high biofilm formation should be minimized in water dispensers, whereas approved polymeric components contribute to biological stability in the dispensed drinking water.
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Affiliation(s)
- Ji Won Park
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Republic of Korea
| | - Keun-Yeong Park
- Department of Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea
| | - Yeong Na
- Department of Environmental System Engineering, Korea University, 2511 Sejong-ro, Sejong City, 30019, Republic of Korea
| | - Sangjung Park
- Water Supply and Sewerage Research Division, National Institute of Environmental Research, Hwangyeong-ro 42, Seo-gu, Incheon, 22689, Republic of Korea
| | - Sungpyo Kim
- Department of Environmental System Engineering, Korea University, 2511 Sejong-ro, Sejong City, 30019, Republic of Korea
| | - Ji Hyang Kweon
- Department of Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea
| | - Sung Kyu Maeng
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Republic of Korea.
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33
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Maeng M, Shahi NK, Shin G, Son H, Kwak D, Dockko S. Formation characteristics of carbonaceous and nitrogenous disinfection by-products depending on residual organic compounds by CGS and DAF. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:34008-34017. [PMID: 30209770 DOI: 10.1007/s11356-018-2919-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/06/2018] [Indexed: 06/08/2023]
Abstract
Allogenic organic matter (AOM) composed of extracellular and intracellular organic matter (EOM and IOM) is a major precursor of halogenated carbonaceous and nitrogenous disinfection by-products (C-DBPs and N-DBPs) upon chlorination. The EOM and IOM extracted from Microcystis aeruginosa were analyzed based on bulk parameters and organic fractions with different molecular weight by liquid chromatography with organic carbon detection (LC-OCD). It investigated the efficiency of a conventional gravity system (CGS) and dissolved air flotation (DAF) in the removal of organic precursors, together with measurement of the formation of four major trihalomethanes (THMs) and haloacetonitriles (HANs) in treated water upon chlorination. The results showed that EOM accounted for 59% of building blocks and humic substances, whereas for IOM, 54% were low molecular weight (LMW) neutrals. Both CGS and DAF showed 57-59% removal of dissolved organic carbon (DOC) from EOM and IOM. Regarding DON removal, DAF was found to be more effective, i.e., 8% higher than CGS for EOM. Moreover, the removal of LMW acids and neutrals (not easy to remove and are major precursors of DBPs) from EOM and IOM by DAF was higher than from CGS. The amounts of DBPs measured in all the samples treated for interchlorination were much lower than in the samples for prechlorination. Although the precursors of EOM had a higher concentration than in IOM, THMs and HANs were detected for IOM at a higher concentration, which might be attributed to higher amounts of aromatic, aliphatic moisture and protein compounds in the IOM. Comparatively, DAF showed lower THM and HAN values than CGS water, particularly for IOM. Also, DAF showed a sharp decrease in THMs and an insignificant increase in HANs according to time.
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Affiliation(s)
- Minsoo Maeng
- Department of Civil and Environmental Engineering, Dankook University, Yongin-si, Gyeonggi-do, 448-701, Republic of Korea
| | - Nirmal Kumar Shahi
- Department of Civil and Environmental Engineering, Dankook University, Yongin-si, Gyeonggi-do, 448-701, Republic of Korea
| | - Gwyam Shin
- Department of Environmental Engineering, Ajou University, 206 world-cup-ro, Yeongtong-gu, Suwon-si, 443-749, Republic of Korea
| | - Heejong Son
- Water Quality Institute, Water Authority, Busan, 614-854, Republic of Korea
| | - Dongheui Kwak
- Jeongeup Industry-Academic Cooperation Support Center, Chonbuk National University, 9 Cheomdan Rd, Jeongeup, Jeonbuk, 56212, Republic of Korea
| | - Seok Dockko
- Department of Civil and Environmental Engineering, Dankook University, Yongin-si, Gyeonggi-do, 448-701, Republic of Korea.
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34
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Schurer R, Schippers JC, Kennedy MD, Cornelissen ER, Salinas-Rodriguez SG, Hijnen WAM, van der Wal A. Enhancing biological stability of disinfectant-free drinking water by reducing high molecular weight organic compounds with ultrafiltration posttreatment. WATER RESEARCH 2019; 164:114927. [PMID: 31401326 DOI: 10.1016/j.watres.2019.114927] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 07/27/2019] [Accepted: 07/29/2019] [Indexed: 06/10/2023]
Abstract
The production of biologically stable drinking water is challenging in conventional surface water treatment plants. However, attainment of biological stability is essential to avoid regrowth in disinfectant-free distribution systems. A novel application of ultrafiltration as a posttreatment step to enhance biological stability of drinking water produced in an existing conventional surface water treatment plant was investigated. The conventional full-scale plant comprised coagulation/sedimentation/filtration, UV-disinfection, biological activated carbon filtration and chlorine dioxide post-disinfection. The produced water exhibited substantial regrowth of Aeromonads, invertebrates and colony counts in the distribution network. Recent literature attributes this phenomenon to the specific presence of slowly biodegradable, high molecular weight (MW) biopolymeric organic compounds. Hence, the aim of this study is to enhance the biological stability of conventionally treated surface water by reducing the concentration of high-MW organic compounds. For this purpose, biological active carbon filtrate was subjected to ultrafiltration with membrane pore sizes of 10 kDa, 150 kDa and 0.12 μm respectively, operating in parallel. The UF performance was evaluated in terms of the achieved reduction in particulate and high-MW organic carbon (PHMOC); the biopolymer fraction in Liquid Chromatography-Organic Carbon Detection; biomass (cells, ATP); Assimilable Organic Carbon (AOC) by the AOC-P17/NOX method for easily biodegradable, low-MW compounds and by the AOC-A3 method for slowly biodegradable, high-MW compounds; and overall microbial growth potential (MGP) as assessed by Biomass Production Potential (BPP) and Bacterial Growth Potential (BGP) bio-assays. Results showed increasing removal of high-MW organic carbon with decreasing UF pore size, i.e., 30%, 60% and 70% removal was observed for the 0.12 μm, 150 kDa and 10 kDa membranes, respectively. Biomass and particulates retention was more than 95% for all UF membranes. AOC-A3, BPP and BGP were substantially reduced by 90%, 70% and 50%, respectively. These respective reductions were similar for all three UF membranes despite their difference in pore size. Easily biodegradable organic compounds (as AOC-P17/NOX) were not reduced by any of the membranes, which was in accordance with expectations considering the low MW of the compounds involved. Based on the obtained results, growth potential appears to be largely attributable to high-MW organic compounds which are retained by a 0.12 μm UF membrane. Furthermore, the quality of all three UF permeates was equal to or better than in reference cases (literature data) which exhibit little regrowth in their disinfectant-free distribution networks. The results demonstrate that ultrafiltration posttreatment in conventional surface water treatment plants is a potentially promising approach to enhance the biological stability of drinking water.
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Affiliation(s)
- R Schurer
- Evides Water Company, P.O. Box 4472, 3006 AL, Rotterdam, the Netherlands; Department of Environmental Technology, Wageningen University, Bornse Weilanden 9, 6708 WG, Wageningen, the Netherlands; IHE Delft Institute for Water Education, Environmental Engineering and Water Technology Department, Westvest 7, 2611 AX, Delft, the Netherlands.
| | - J C Schippers
- IHE Delft Institute for Water Education, Environmental Engineering and Water Technology Department, Westvest 7, 2611 AX, Delft, the Netherlands
| | - M D Kennedy
- IHE Delft Institute for Water Education, Environmental Engineering and Water Technology Department, Westvest 7, 2611 AX, Delft, the Netherlands
| | - E R Cornelissen
- KWR Watercycle Research Institute, P.O. Box 1072, 3433 PE, Nieuwegein, the Netherlands; Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore, 637141, Singapore; Particle and Interfacial Technology Group, Ghent University, Coupure Links 653, B-9000, Ghent, Belgium
| | - S G Salinas-Rodriguez
- IHE Delft Institute for Water Education, Environmental Engineering and Water Technology Department, Westvest 7, 2611 AX, Delft, the Netherlands
| | - W A M Hijnen
- Evides Water Company, P.O. Box 4472, 3006 AL, Rotterdam, the Netherlands; KWR Watercycle Research Institute, P.O. Box 1072, 3433 PE, Nieuwegein, the Netherlands
| | - A van der Wal
- Evides Water Company, P.O. Box 4472, 3006 AL, Rotterdam, the Netherlands; Department of Environmental Technology, Wageningen University, Bornse Weilanden 9, 6708 WG, Wageningen, the Netherlands
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35
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Ho HJ, Cao JW, Kao CM, Lai WL. Characterization of released metabolic organics during AOC analyses by P17 and NOX strains using 3-D fluorescent signals. CHEMOSPHERE 2019; 222:205-213. [PMID: 30708154 DOI: 10.1016/j.chemosphere.2019.01.115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 01/03/2019] [Accepted: 01/20/2019] [Indexed: 06/09/2023]
Abstract
Assimilable organic carbon (AOC) serves as an indicator of the biostability of drinking water distribution systems; however, the properties of the released organic metabolites by Pseudomonas fluorescens (P17) and Spirillum (NOX) used in AOC bioassays are seldom discussed. In this study, fluorescence excitation emission matrix (FEEM) was selected to characterize organic metabolites after substrate biotransformation and their divergences at different growth stages of both strains in AOC bioassay. Excellent correlation between ATP and colony-forming units (CFUs) was observed for both strains. The concentration of ATP per colony was six times higher in the P17 strain than in the NOX strain. A retarding phenomenon was observed for the NOX strain in the presence of high acetate-C content (100-150 μg acetate-C/L). The fluorescence wavelength peaks were wider for the protein-like substance released by the P17 strain than for those released by the NOX strain. However, fluorescent fulvic-like substances only existed in the NOX strain. Relative humus accumulation (RHA), the ratio of protein-like fluorescence intensity to humus-like fluorescence intensity, decreased in the P17 strain but substantially increased in the NOX strain in the logarithmic growth phase. RHA showed a descending trend for the P17 strain as compared to that of the NOX strain during the progress from logarithmic to stationary growth phase at three different acetate-C concentrations; however, the opposite was observed at 100 μg acetate-C/L, indicating that high acetate-C content may affect the properties of released organic matter from both strains.
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Affiliation(s)
- Hsiao-Jung Ho
- Institute of Environmental Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Jing-Wen Cao
- Graduate School of Environmental Management, Tajen University, Pingtung, Taiwan
| | - Chih-Ming Kao
- Institute of Environmental Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Wen-Liang Lai
- Graduate School of Environmental Management, Tajen University, Pingtung, Taiwan.
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36
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Safford HR, Bischel HN. Flow cytometry applications in water treatment, distribution, and reuse: A review. WATER RESEARCH 2019; 151:110-133. [PMID: 30594081 DOI: 10.1016/j.watres.2018.12.016] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 11/30/2018] [Accepted: 12/01/2018] [Indexed: 06/09/2023]
Abstract
Ensuring safe and effective water treatment, distribution, and reuse requires robust methods for characterizing and monitoring waterborne microbes. Methods widely used today can be limited by low sensitivity, high labor and time requirements, susceptibility to interference from inhibitory compounds, and difficulties in distinguishing between viable and non-viable cells. Flow cytometry (FCM) has recently gained attention as an alternative approach that can overcome many of these challenges. This article critically and systematically reviews for the first time recent literature on applications of FCM in water treatment, distribution, and reuse. In the review, we identify and examine nearly 300 studies published from 2000 to 2018 that illustrate the benefits and challenges of using FCM for assessing source-water quality and impacts of treatment-plant discharge on receiving waters, wastewater treatment, drinking water treatment, and drinking water distribution. We then discuss options for combining FCM with other indicators of water quality and address several topics that cut across nearly all applications reviewed. Finally, we identify priority areas in which more work is needed to realize the full potential of this approach. These include optimizing protocols for FCM-based analysis of waterborne viruses, optimizing protocols for specifically detecting target pathogens, automating sample handling and preparation to enable real-time FCM, developing computational tools to assist data analysis, and improving standards for instrumentation, methods, and reporting requirements. We conclude that while more work is needed to realize the full potential of FCM in water treatment, distribution, and reuse, substantial progress has been made over the past two decades. There is now a sufficiently large body of research documenting successful applications of FCM that the approach could reasonably and realistically see widespread adoption as a routine method for water quality assessment.
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Affiliation(s)
- Hannah R Safford
- Department of Civil and Environmental Engineering, University of California Davis, 2001 Ghausi Hall, 480 Bainer Hall Drive, 95616, Davis, CA, United States
| | - Heather N Bischel
- Department of Civil and Environmental Engineering, University of California Davis, 2001 Ghausi Hall, 480 Bainer Hall Drive, 95616, Davis, CA, United States.
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37
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Bang WH, Jung Y, Park JW, Lee S, Maeng SK. Effects of hydraulic loading rate and organic load on the performance of a pilot-scale hybrid VF-HF constructed wetland in treating secondary effluent. CHEMOSPHERE 2019; 218:232-240. [PMID: 30471504 DOI: 10.1016/j.chemosphere.2018.11.110] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 10/03/2018] [Accepted: 11/15/2018] [Indexed: 06/09/2023]
Abstract
This study evaluated the performance of a pilot-scale hybrid constructed wetland system for secondary effluent and investigated bulk organic matter characteristics. The hybrid constructed wetland consisted of a vertical-flow (VF) bed followed by a horizontal-flow (HF) bed. We also investigated the effects of hydraulic loading rates and influent organic load on the performance of the pilot-scale VF-HF hybrid constructed wetland. The results showed a high removal efficiency for suspended solids (>95%) and organic matter as determined by total organic carbon (>98.5%) and dissolved organic carbon (>70%), but no significant change in nitrogen removal was observed. The wetland treatment efficiency for suspended solids and organic matter showed a good buffer capacity even when hydraulic loading rates increased from 750 to 1500 L m-2 d-1 and 500-1000 L m-2 d-1 during the VF and HF stages, respectively. Moreover, there was no significant change in the performance when influent organic load increased eight-fold. Fluorescence excitation-emission matrix and liquid chromatography-organic carbon detection (LC-OCD) were used to investigate the dissolved organic matter characteristics in the hybrid VF-HF constructed wetland. Fluorescence excitation-emission matrix spectroscopy showed that both protein- and humic-like substances did not significantly change in the effluent when hydraulic loading rates and organic load increased by two- and eight-fold, respectively. Biopolymers determined using LC-OCD were effectively removed via the VF and HF stage wetlands, indicating the occurrence of biodegradation. Fluorescence excitation-emission matrix spectroscopy and LC-OCD provided the fate of dissolved organic matter characteristics in the hybrid VF-HF constructed wetland.
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Affiliation(s)
- Woo Hyuck Bang
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-Gu, Seoul, 05006, Republic of Korea
| | - Yeonsung Jung
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-Gu, Seoul, 05006, Republic of Korea
| | - Ji Won Park
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-Gu, Seoul, 05006, Republic of Korea
| | - Seunghak Lee
- Center for Water Resource Cycle, Green City Technology Institute, Korea Institute of Science and Technology, 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul, 02792, Republic of Korea
| | - Sung Kyu Maeng
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-Gu, Seoul, 05006, Republic of Korea.
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Abstract
A field study was carried out to investigate the feasibility of a riverbank filtration site using two vertical wells on the Nakdong River, South Korea. The riverbank filtration site was designed to have eleven horizontal collector wells in order to supply 280,000 m3/day. This field study provided more insight into the fate of the dissolved organic matter’s characteristics during soil passage. The vertical production wells (PWs) were located in different aquifer materials (PW-Sand and PW-Gravel) in order to determine the depth of the laterals for the horizontal collector wells. The turbidity of the riverbank filtrates from the PW-Sand (0.9 NTU) and PW-Gravel (0.7 NTU) was less than 1 NTU, which was the target turbidity of the riverbank filtrate in this study. The iron concentrations were 18.1 ± 0.8 and 25.9 ± 1.3 mg/L for PW-Sand and PW-Gravel respectively, and were higher than those of the land-side groundwater. The biodegradable organic matter-determined biochemical oxygen demand in the river water was reduced by more than 40% during soil passage, indicating that less microbial growth in the riverbank filtrate could be possible. Moreover, the influence of the pumping rates of the vertical wells on the removal of dissolved organic matter and the turbidity was not significant.
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Sousi M, Liu G, Salinas-Rodriguez SG, Knezev A, Blankert B, Schippers JC, van der Meer W, Kennedy MD. Further developing the bacterial growth potential method for ultra-pure drinking water produced by remineralization of reverse osmosis permeate. WATER RESEARCH 2018; 145:687-696. [PMID: 30212807 DOI: 10.1016/j.watres.2018.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 08/15/2018] [Accepted: 09/02/2018] [Indexed: 06/08/2023]
Abstract
Ensuring the biological stability of drinking water is essential for modern drinking water supply. To understand and manage the biological stability, it is critical that the bacterial growth in drinking water can be measured. Nowadays, advance treatment technologies, such as reverse osmosis (RO), are increasingly applied in drinking water purification where the produced water is characterized by low levels of nutrients and cell counts. The challenge is, therefore, how to measure the low bacterial growth potential (BGP) of such ultra-pure water using the available methods which were originally developed for conventionally treated drinking water. In this study, we proposed a protocol to assess BGP of ultra-pure drinking water produced by RO and post-treatment (including remineralization). Natural bacterial consortium from conventional drinking water was added to all water samples during this study to ensure the presence of a wide range of bacterial strains. The method development included developing an ultra-pure blank with high reproducibility to lower the detection limit of the BGP method (50 ± 20 × 103 intact cells/mL) compared with conventional blanks such as bottled spring water, deep groundwater treated by aeration and slow sand filtrate of surface water supply. The ultra-low blank consists of RO permeate after adjusting its pH and essential mineral content under controlled laboratory conditions to ensure carbon limitation. Regarding the test protocol, inoculum concentrations of >10 × 103 intact cells/mL may have a significant contribution to the measured low levels of BGP. Pasteurization of water samples before measuring BGP is necessary to ensure reliable bacterial growth curves. The optimized method was used to assess BGP of ultra-pure drinking water produced by RO membranes and post-treatment (including remineralization), where the BGP has decreased more than 6-fold to a level of 90 ± 20 × 103 intact cells/mL compared with conventionally treated water (630 ± 70 × 103 intact cells/mL).
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Affiliation(s)
- Mohaned Sousi
- Department of Environmental Engineering and Water Technology, IHE Delft Institute for Water Education, Westvest 7, 2611 AX, Delft, the Netherlands; Faculty of Science and Technology, University of Twente, Drienerlolaan 5, 7522 NB, Enschede, the Netherlands
| | - Gang Liu
- Oasen Drinkwater, Nieuwe Gouwe O.Z. 3, 2801 SB, Gouda, the Netherlands; Department of Water Management, Faculty of Civil Engineering and Geoscience, Delft University of Technology, Stevinweg 1, 2628 CN, Delft, the Netherlands.
| | - Sergio G Salinas-Rodriguez
- Department of Environmental Engineering and Water Technology, IHE Delft Institute for Water Education, Westvest 7, 2611 AX, Delft, the Netherlands
| | - Aleksandra Knezev
- Het Waterlaboratorium, J.W. Lucasweg 2, 2031 BE, Haarlem, the Netherlands
| | - Bastiaan Blankert
- Oasen Drinkwater, Nieuwe Gouwe O.Z. 3, 2801 SB, Gouda, the Netherlands
| | - Jan C Schippers
- Department of Environmental Engineering and Water Technology, IHE Delft Institute for Water Education, Westvest 7, 2611 AX, Delft, the Netherlands
| | - Walter van der Meer
- Faculty of Science and Technology, University of Twente, Drienerlolaan 5, 7522 NB, Enschede, the Netherlands; Oasen Drinkwater, Nieuwe Gouwe O.Z. 3, 2801 SB, Gouda, the Netherlands
| | - Maria D Kennedy
- Department of Environmental Engineering and Water Technology, IHE Delft Institute for Water Education, Westvest 7, 2611 AX, Delft, the Netherlands; Department of Water Management, Faculty of Civil Engineering and Geoscience, Delft University of Technology, Stevinweg 1, 2628 CN, Delft, the Netherlands
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Park JW, Lee YJ, Meyer AS, Douterelo I, Maeng SK. Bacterial growth through microfiltration membranes and NOM characteristics in an MF-RO integrated membrane system: Lab-scale and full-scale studies. WATER RESEARCH 2018; 144:36-45. [PMID: 30014977 DOI: 10.1016/j.watres.2018.07.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Revised: 07/07/2018] [Accepted: 07/10/2018] [Indexed: 06/08/2023]
Abstract
Biofilm formation on membrane surfaces causes many operational problems such as a decrease in permeate flux and an increase in hydraulic resistance. In this study, the ability of bacteria to pass through microfiltration (MF) membranes and the growth potential of microfilterable bacteria were investigated in order to understand biofouling in MF-reverse osmosis (RO) integrated membrane systems. Growth of microfilterable bacteria in MF permeate was observed, indicating that not all MF membranes can guarantee the total rejection of bacteria. Changes in natural organic matter (NOM) characteristics and growth potential of bacteria during the treatment process are important factors in the occurrence of biofilm development in water treatment systems. Analysis of protein-like and humic-like substances in NOM of two successive RO stages revealed an increase in the concentrations of both biopolymers and humic substances of RO concentrates. Unexpectedly, the use of antiscalants was seen to enhance the growth of bacteria in the RO feed water in this study. Bacterial 16s rRNA pyrosequencing revealed that passing source water through the MF membranes dramatically changed bacterial community structure. The bacterial communities that passed through the MF steps primarily belonged to the family Comamonadaceae. However, several bacteria groups including Flavobacteriaceae, Sphingobacteriaceae and Sphingomonadaceae selectively composed the biofilm community formed on the RO membranes. Thus, understanding the selectivity and filterability of MF towards microorganisms involved in biofouling on RO membrane surfaces is crucial for the improvement of membrane-related operational processes.
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Affiliation(s)
- Ji Won Park
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Republic of Korea
| | - Young Joo Lee
- K-water Convergence Institute, 125 Yuseong-daero 1689 beon-gil, Yuseong-gu, Deajeon, 34045, Republic of Korea
| | - Anne S Meyer
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, the Netherlands
| | - Isabel Douterelo
- Pennine Water Group, Department of Civil and Structural Engineering, The University of Sheffield, Sheffield, United Kingdom
| | - Sung Kyu Maeng
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Republic of Korea.
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Pramanik BK, Roddick FA, Fan L. Impact of biological activated carbon pre-treatment on the hydrophilic fraction of effluent organic matter for mitigating fouling in microfiltration. ENVIRONMENTAL TECHNOLOGY 2018; 39:2243-2250. [PMID: 28689477 DOI: 10.1080/09593330.2017.1354072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 07/06/2017] [Indexed: 06/07/2023]
Abstract
The hydrophilic (HPI) fraction of effluent organic matter, which has protein and carbohydrate contents, has a high propensity to foul low-pressure membranes. Biological activated carbon (BAC) filtration was examined as a pre-treatment for reducing the fouling of a microfiltration (MF) membrane (0.1 µm PVDF) by the HPI organic fraction extracted from a biologically treated secondary effluent (BTSE). Although the BAC removed less dissolved organic carbon, carbohydrate and protein from the HPI fraction than the granular activated carbon treatment which was used for comparison, it led to better improvement in permeate flux. This was shown to be due to the removal/breakdown of the HPI fraction resulting in less deposition of these organics on the membrane, many components of which are high molecular weight biopolymers (such as protein and carbohydrate molecules) through biodegradation and adsorption of those molecules on the biofilm and activated carbon. This study established the potential of BAC pre-treatment for reducing the HPI fouling of the membrane and thus improving the performance for the MF of BTSE for water reclamation.
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Affiliation(s)
| | | | - Linhua Fan
- a School of Engineering , RMIT University , Melbourne , Australia
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Chan S, Pullerits K, Riechelmann J, Persson KM, Rådström P, Paul CJ. Monitoring biofilm function in new and matured full-scale slow sand filters using flow cytometric histogram image comparison (CHIC). WATER RESEARCH 2018; 138:27-36. [PMID: 29571086 DOI: 10.1016/j.watres.2018.03.032] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 03/09/2018] [Accepted: 03/12/2018] [Indexed: 06/08/2023]
Abstract
While slow sand filters (SSFs) have produced drinking water for more than a hundred years, understanding of their associated microbial communities is limited. In this study, bacteria in influent and effluent water from full-scale SSFs were explored using flow cytometry (FCM) with cytometric histogram image comparison (CHIC) analysis; and routine microbial counts for heterotrophs, total coliforms and Escherichia coli. To assess if FCM can monitor biofilm function, SSFs differing in age and sand composition were compared. FCM profiles from two established filters were indistinguishable. To examine biofilm in the deep sand bed, SSFs were monitored during a scraping event, when the top layer of sand and the schmutzdecke are removed to restore flow through the filter. The performance of an established SSF was stable: total organic carbon (TOC), pH, numbers of heterotrophs, coliforms, E. coli, and FCM bacterial profile were unaffected by scraping. However, the performance of two newly-built SSFs containing new and mixed sand was compromised: breakthrough of both microbial indicators and TOC occurred following scraping. The compromised performance of the new SSFs was reflected in distinct effluent bacterial communities; and, the presence of microbial indicators correlated to influent bacterial communities. This demonstrated that FCM can monitor SSF performance. Removal of the top layer of sand did not alter the effluent water from the established SSF, but did affect that of the SSFs containing new sand. This suggests that the impact of the surface biofilm on effluent water is greater when the deep sand bed biofilm is not established.
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Affiliation(s)
- Sandy Chan
- Applied Microbiology, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden; Sweden Water Research AB, Ideon Science Park, Scheelevägen 15, SE-223 70 Lund, Sweden; Sydvatten AB, Hyllie Stationstorg 21, SE-215 32 Malmö, Sweden.
| | - Kristjan Pullerits
- Applied Microbiology, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden; Sweden Water Research AB, Ideon Science Park, Scheelevägen 15, SE-223 70 Lund, Sweden; Sydvatten AB, Hyllie Stationstorg 21, SE-215 32 Malmö, Sweden.
| | - Janine Riechelmann
- Applied Microbiology, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
| | - Kenneth M Persson
- Sweden Water Research AB, Ideon Science Park, Scheelevägen 15, SE-223 70 Lund, Sweden; Sydvatten AB, Hyllie Stationstorg 21, SE-215 32 Malmö, Sweden; Water Resources Engineering, Department of Building and Environmental Technology, Lund University, P.O. Box 118, SE-221 00 Lund, Sweden.
| | - Peter Rådström
- Applied Microbiology, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
| | - Catherine J Paul
- Applied Microbiology, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden; Water Resources Engineering, Department of Building and Environmental Technology, Lund University, P.O. Box 118, SE-221 00 Lund, Sweden.
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Maeng SK, You SH, Nam JY, Ryu H, Timmes TC, Kim HC. The growth of Scenedesmus quadricauda in RO concentrate and the impacts on refractory organic matter, Escherichia coli, and trace organic compounds. WATER RESEARCH 2018; 134:292-300. [PMID: 29433079 PMCID: PMC6744953 DOI: 10.1016/j.watres.2018.01.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 01/12/2018] [Accepted: 01/13/2018] [Indexed: 05/31/2023]
Abstract
This study achieves a better operational simplicity for the phycoremediation of reverse osmosis (RO) concentrate using Scenedesmus quadricauda microalgae. Under continuous illumination with CO2 supplementation, algal growth in the RO concentrate resulted in a conversion of polymeric organic matter (a mixture of humic substances and polysaccharides) to biodegradable fractions and their prompt removal along with inorganic nutrients (NO3- and PO43-). The algal-induced degradation of humic-like substances which are typically refractory to microbial decomposition was demonstrated in an indirect manner. In this study, we also investigated the effects of algal treatment on the growth of Escherichia coli and removal of trace organic compounds (TOrCs) from the RO concentrate. Our results indicate that algal treatment of the RO concentrate using aeration with 10% (v/v) CO2 under continuous illumination is highly feasible as a safe and inexpensive technology to remove non- or slowly-biodegradable organic matter, reduce enteric bacteria, and attenuate TOrCs in wastewater. However, the results should not be generalized, but critically discussed, due to limitations of using the synthetic RO concentrate in evaluating the performance of wastewater remediation with microalgae.
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Affiliation(s)
- Sung Kyu Maeng
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Republic of Korea.
| | - Song Hee You
- Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Republic of Korea.
| | - Joo-Youn Nam
- Jeju Global Research Center, Korea Institute of Energy Research, 200 Haemajihaean-ro, Gujwa-eup, Jeju-si, Jeju-do 63357, Republic of Korea.
| | - Hodon Ryu
- United States Environmental Protection Agency, Office Research and Development, 26 W. Martin Luther King Dr., Cincinnati, OH 45268, USA.
| | - Thomas C Timmes
- Department of Civil and Environmental Engineering, Virginia Military Institute, Lexington, VA 24450, USA.
| | - Hyun-Chul Kim
- Water Resources Research Institute, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Republic of Korea.
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Stylianou SK, Katsoyiannis IA, Ernst M, Zouboulis AI. Impact of O 3 or O 3/H 2O 2 treatment via a membrane contacting system on the composition and characteristics of the natural organic matter of surface waters. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:12246-12255. [PMID: 28656574 DOI: 10.1007/s11356-017-9554-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 06/14/2017] [Indexed: 06/07/2023]
Abstract
The present study aims to evaluate changes in the structure-composition of natural organic matter (NOM) that occur after the application of bubbleless ozonation or peroxone treatment of surface waters. The oxidation experiments (using 0.5-2 mg O3/mg DOC, or 2:1 O3:H2O2 molar ratio) were performed in a continuous mode, using a tubular ceramic membrane contactor. Fluorescence spectroscopy (emission-excitation matrix) and liquid chromatography-organic carbon detection (LC-OCD) were mainly used for the detailed DOC characterization. In brief, the application of single ozonation resulted to high reduction of humic-like peak fluorescence intensities (50-85%) and also to the formation of two new peaks in the region of protein-like components. The co-addition of H2O2 did not present the anticipated increase in the reduction of fluorescence intensity; however, it resulted to the further oxidation of protein-like fluorophores. LC-OCD measurements confirmed the decrease of average molecular weight of NOM during ozone treatment, due to the gradual degradation of biopolymers (14-23%) and humic substances (11-17%) towards building blocks and low molecular weight (LMW) neutrals. Advanced oxidation process (AOP) treatment by the mixture O3/H2O2 resulted in the simultaneous decrease of building blocks and LMW neutral concentrations. Conventional batch ozonation and AOP experiments were conducted using ozone-saturated solutions to investigate the effect of different contacting patterns. The results revealed that the different reaction pathways followed during bubbleless and conventional batch experiments may also influence the formation of NOM oxidation intermediates.
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Affiliation(s)
- Stylianos K Stylianou
- Department of Chemistry, Laboratory of Chemical and Environmental Technology, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Ioannis A Katsoyiannis
- Department of Chemistry, Laboratory of Chemical and Environmental Technology, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Mathias Ernst
- Institute for Water Resources and Water Supply, Hamburg University of Technology, Am Schwarzenberg-Campus 3, 21073, Hamburg, Germany
| | - Anastasios I Zouboulis
- Department of Chemistry, Laboratory of Chemical and Environmental Technology, Aristotle University of Thessaloniki, Thessaloniki, Greece.
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45
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Hijnen WAM, Schurer R, Bahlman JA, Ketelaars HAM, Italiaander R, van der Wal A, van der Wielen PWJJ. Slowly biodegradable organic compounds impact the biostability of non-chlorinated drinking water produced from surface water. WATER RESEARCH 2018; 129:240-251. [PMID: 29153877 DOI: 10.1016/j.watres.2017.10.068] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 10/27/2017] [Accepted: 10/29/2017] [Indexed: 05/16/2023]
Abstract
It is possible to distribute drinking water without a disinfectant residual when the treated water is biologically stable. The objective of this study was to determine the impact of easily and slowly biodegradable compounds on the biostability of the drinking water at three full-scale production plants which use the same surface water, and on the regrowth conditions in the related distribution systems. Easily biodegradable compounds in the drinking water were determined with AOC-P17/Nox during 2012-2015. Slowly biodegradable organic compounds measured as particulate and/or high-molecular organic carbon (PHMOC), were monitored at the inlet and after the different treatment stages of the three treatments during the same period. The results show that PHMOC (300-470 μg C L-1) was approximately 10% of the TOC in the surface water and was removed to 50-100 μg C L-1. The PHMOC in the water consisted of 40-60% of carbohydrates and 10% of proteins. A significant and strong positive correlation was observed for PHMOC concentrations and two recently introduced bioassay methods for slowly biodegradable compounds (AOC-A3 and biomass production potential, BPC14). Moreover, these three parameters in the biological active carbon effluent (BACF) of the three plants showed a positive correlation with regrowth in the drinking water distribution system, which was assessed with Aeromonas, heterotrophic plate counts, coliforms and large invertebrates. In contrast, the AOC-P17/Nox concentrations did not correlate with these regrowth parameters. We therefore conclude that slowly biodegradable compounds in the treated water from these treatment plants seem to have a greater impact on regrowth in the distribution system than easily biodegradable compounds.
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Affiliation(s)
- W A M Hijnen
- Evides Water Company, PO Box 4472, 3006 AL Rotterdam, The Netherlands; KWR Watercycle Research Institute, P.O. Box 1072, 3430 BB Nieuwegein, The Netherlands.
| | - R Schurer
- Evides Water Company, PO Box 4472, 3006 AL Rotterdam, The Netherlands
| | - J A Bahlman
- Evides Water Company, PO Box 4472, 3006 AL Rotterdam, The Netherlands
| | - H A M Ketelaars
- Evides Water Company, PO Box 4472, 3006 AL Rotterdam, The Netherlands
| | - R Italiaander
- KWR Watercycle Research Institute, P.O. Box 1072, 3430 BB Nieuwegein, The Netherlands
| | - A van der Wal
- Evides Water Company, PO Box 4472, 3006 AL Rotterdam, The Netherlands; Department of Environmental Technology, Wageningen University, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands
| | - P W J J van der Wielen
- KWR Watercycle Research Institute, P.O. Box 1072, 3430 BB Nieuwegein, The Netherlands; Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen, The Netherlands
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Chen S, Yuan Z, Hanigan D, Westerhoff P, Zhao H, Ni J. Coagulation behaviors of new covalently bound hybrid coagulants (CBHyC) in surface water treatment. Sep Purif Technol 2018. [DOI: 10.1016/j.seppur.2017.10.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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47
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Liao X, Zou R, Chen C, Yuan B, Zhou Z, Zhang X. Evaluating the biosafety of conventional and O 3-BAC process and its relationship with NOM characteristics. ENVIRONMENTAL TECHNOLOGY 2018; 39:221-230. [PMID: 28274190 DOI: 10.1080/09593330.2017.1297850] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 02/15/2017] [Indexed: 06/06/2023]
Abstract
It is the priority to guarantee biosafety for drinking water treatment. The objective of this study was to evaluate the impact of widely applied conventional and ozone-biological activated carbon (O3-BAC) advanced treatment technology on biosafety of drinking water. The items, including assimilable organic carbon (AOC), biodegradable dissolved organic carbon (BDOC), heterotrophic plate counts (HPCs) and the microorganism community structures, were used to evaluate the biosafety. Moreover, their relationships with molecular weights (MWs) and fluorescence intensity of dissolved organic matter were investigated. The results indicated that the technology provided a considerable gain in potable water quality by decreasing dissolved organic carbon (DOC, from 5.05 to 1.71 mg/L), AOC (from 298 to 131 μg/L), BDOC (from 1.39 to 0.24 mg/L) and HPCs (from 275 to 10 CFU/mL). Ozone brought an increase in DOC with low MW <1 kDa, which accompanies with an increase in AOC/BDOC concentration, which could be reduced effectively by subsequent BAC process. The formation of AOC/BDOC was closely related to DOC with low MWs and aromatic protein. Bacteria could be released from BAC filter, resulting in an increase in HPC and the presence of pathogenic bacteria in effluent, while the post sand filter could further guarantee the biosafety of finished water.
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Affiliation(s)
- Xiaobin Liao
- a Institute of Municipal and Environmental Engineering, College of Civil Engineering , Huaqiao University , Xiamen , People's Republic of China
- b State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment , Tsinghua University , Beijing , People's Republic of China
| | - Rusen Zou
- a Institute of Municipal and Environmental Engineering, College of Civil Engineering , Huaqiao University , Xiamen , People's Republic of China
| | - Chao Chen
- b State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment , Tsinghua University , Beijing , People's Republic of China
| | - Baoling Yuan
- a Institute of Municipal and Environmental Engineering, College of Civil Engineering , Huaqiao University , Xiamen , People's Republic of China
| | - Zhenming Zhou
- a Institute of Municipal and Environmental Engineering, College of Civil Engineering , Huaqiao University , Xiamen , People's Republic of China
| | - Xiaojian Zhang
- b State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment , Tsinghua University , Beijing , People's Republic of China
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So SH, Choi IH, Kim HC, Maeng SK. Seasonally related effects on natural organic matter characteristics from source to tap in Korea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 592:584-592. [PMID: 28320524 DOI: 10.1016/j.scitotenv.2017.03.063] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2017] [Revised: 03/05/2017] [Accepted: 03/07/2017] [Indexed: 06/06/2023]
Abstract
In this study, natural organic matter (NOM) characteristics were investigated over three years of monthly monitoring to determine the effect of seasonal variations on NOM levels from source to tap. Liquid chromatography with organic carbon detection (LC-OCD) was used to determine NOM characteristics and the level of reduction of biodegradable dissolved organic carbon (BDOC). The average dissolved organic matter concentration in the source water (Lake Paldang, Korea) was not significantly different between summer and winter. However, the distribution of NOM components, such as biopolymers, building blocks, low molecular weight (MW) neutrals and acids, identified by LC-OCD, varied seasonally. While high MW NOM was preferentially removed by coagulation/sedimentation/rapid sand filtration (CSR), no seasonal effects were observed on the removal of high MW NOM. CSR and biological activated carbon (BAC) filtration showed a better efficiency of BDOC removal in winter and summer, respectively. High concentrations of chlorine used in the treatment plants in summer resulted in 10% higher DOC concentrations during disinfection. Overall NOM removal efficiencies from source to tap were 45% and 35% for summer and winter, respectively. Principal component analysis also indicated that seasonal variations (principal component 1) showed the strongest positive correlation with the overall performance of water treatment. The long-term monitoring of drinking water treatment processes showed that seasonal variations were important factors affecting NOM characteristics during water treatment.
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Affiliation(s)
- S H So
- Department of Civil and Environmental Engineering, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747, Republic of Korea
| | - I H Choi
- Water Analysis and Research Center, K-water, 560 Sintanjin-ro, Daedeok-gu, Daejeon, Republic of Korea
| | - H C Kim
- Water Resources Research Institute, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747, Republic of Korea
| | - S K Maeng
- Department of Civil and Environmental Engineering, Sejong University, 98 Gunja-Dong, Gwangjin-Gu, Seoul 143-747, Republic of Korea.
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