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Yu Y, Hossain MM, Sikder R, Qi Z, Huo L, Chen R, Dou W, Shi B, Ye T. Exploring the potential of machine learning to understand the occurrence and health risks of haloacetic acids in a drinking water distribution system. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 951:175573. [PMID: 39153609 DOI: 10.1016/j.scitotenv.2024.175573] [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: 07/08/2024] [Revised: 08/07/2024] [Accepted: 08/14/2024] [Indexed: 08/19/2024]
Abstract
Determining the occurrence of disinfection byproducts (DBPs) in drinking water distribution system (DWDS) remains challenging. Predicting DBPs using readily available water quality parameters can help to understand DBPs associated risks and capture the complex interrelationships between water quality and DBP occurrence. In this study, we collected drinking water samples from a distribution network throughout a year and measured the related water quality parameters (WQPs) and haloacetic acids (HAAs). 12 machine learning (ML) algorithms were evaluated. Random Forest (RF) achieved the best performance (i.e., R2 of 0.78 and RMSE of 7.74) for predicting HAAs concentration. Instead of using cytotoxicity or genotoxicity separately as the surrogate for evaluating toxicity associated with HAAs, we created a health risk index (HRI) that was calculated as the sum of cytotoxicity and genotoxicity of HAAs following the widely used Tic-Tox approach. Similarly, ML models were developed to predict the HRI, and RF model was found to perform the best, obtaining R2 of 0.69 and RMSE of 0.38. To further explore advanced ML approaches, we developed 3 models using uncertainty-based active learning. Our findings revealed that Categorical Boosting Regression (CAT) model developed through active learning substantially outperformed other models, achieving R2 of 0.87 and 0.82 for predicting concentration and the HRI, respectively. Feature importance analysis with the CAT model revealed that temperature, ions (e.g., chloride and nitrate), and DOC concentration in the distribution network had a significant impact on the occurrence of HAAs. Meanwhile, chloride ion, pH, ORP, and free chlorine were found as the most important features for HRI prediction. This study demonstrates that ML has the potential in the prediction of HAA occurrence and toxicity. By identifying key WQPs impacting HAA occurrence and toxicity, this research offers valuable insights for targeted DBP mitigation strategies.
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Affiliation(s)
- Ying Yu
- School of Environmental Science and Engineering, Xiamen University of Technology, Xiamen 361024, China; Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Key Laboratory of Water Resources Utilization and Protection, Xiamen city, Xiamen 361005, China
| | - Md Mahjib Hossain
- Department of Civil and Environmental Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
| | - Rabbi Sikder
- Department of Civil and Environmental Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
| | - Zhenguo Qi
- Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Lixin Huo
- Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Ruya Chen
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310018, Zhejiang, China.
| | - Wenyue Dou
- Key Laboratory of Industrial Pollution Control and Reuse of Jiangsu Province, College of Environmental Engineering, Xuzhou University of Technology, Xuzhou 221018, China
| | - Baoyou Shi
- Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Tao Ye
- Department of Civil and Environmental Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA.
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Hua LC, OuYang RC, Zhao Z, Nguyen TNA, Huang C. Homogeneous versus heterogeneous Mn(II) oxidation in peroxymonosulfate assisting chlorination: Synergistic role for enhanced Mn(II) oxidation in water treatment. WATER RESEARCH 2024; 265:122265. [PMID: 39173357 DOI: 10.1016/j.watres.2024.122265] [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: 01/09/2024] [Revised: 07/19/2024] [Accepted: 08/12/2024] [Indexed: 08/24/2024]
Abstract
Removal of Mn(II) is an essential step for addressing water discoloration in water treatment utilities worldwide. However, conventional chlorination suffers from poor oxidation of Mn(II) due to its low homogeneous oxidation kinetics. This study explored the oxidation capability of a new chemical dosing strategy employing peroxymonosulfate (PMS) to assist the chlorination process (PMS@Cl2) for effective Mn(II) oxidation. The study comprehensively explored both oxidation kinetics and underlying mechanisms associated with homogeneous and heterogeneous oxidation within the PMS@Cl2 system. At an [Mn(II)]0 of 1 mg/L, chlorination demonstrated inability in oxidizing Mn(II), with <10 % oxidation even at an elevated [Cl2] of 150 μM (∼10 mg/L). By contrast, PMS completely oxidized 100 % Mn(II) within a 30-minute reaction at a much lower [PMS] of 60 μM (kobs = 0.07 min-1 and t1/2 = 9 min), demonstrating its superior Mn(II) oxidation kinetics (over one order of magnitude faster than conventional chlorine). PMS@Cl2 exhibited an interesting synergistic benefit when combining a lower dose PMS with a higher routine dose Cl2 (loPMS@hiCl2), e.g. [PMS]:[Cl2] at 15:30 or 30:30 μM. Both conditions achieved 100 % Mn(II) oxidation, with even better values of kobs and t1/2 (0.16-0.17 min-1 and ∼4 min) relative to PMS alone at 60 µM. The synergic benefit of PMS@Cl2 was attributed to distinct functions played by PMS and Cl2 in both homogeneous and heterogeneous oxidation processes. Reactive species identification excluded the possible involvement of SO4•-, OH•, or chlorine radicals in the homogeneous oxidation of the PMS@Cl2 system. Instead, the dominant species was O2•- radical generated during the reaction of Mn(II) and PMS. Furthermore, the heterogeneous oxidation emphasized the important role of combining Cl2 dosing, which demonstrated an increased reactivity and electron transfer with the Mn-O-Mn complex, surpassing PMS. Overall, heterogeneous oxidation accelerated the oxidation kinetics of the PMS@Cl2 system by 1.1-2 orders of magnitude relative to the homogeneous oxidation of Cl2 alone. We here demonstrated that PMS@Cl2 could offer a more efficient mean of soluble Mn(II) mitigation, achieved with a relatively low routine dose of oxidant in a short reaction period. The outcomes of this study would address the existing limitations of traditional chlorine oxidation, minimizing the trade-offs associated with high residual chlorine levels after treatments for soluble manganese-containing water.
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Affiliation(s)
- Lap-Cuong Hua
- Water Supply, Sanitation and Environmental Engineering Department, IHE-Delft Institute for Water Education, Westvest 7, 2611 AX Delft, the Netherlands
| | - Ruei-Ci OuYang
- Institute of Environmental Engineering, National Yang-Ming Chiao Tung University, Hsinchu 300, Taiwan
| | - Ziyin Zhao
- Institute of Environmental Engineering, National Yang-Ming Chiao Tung University, Hsinchu 300, Taiwan
| | - Thi Ngoc Anh Nguyen
- Institute of Environmental Engineering, National Yang-Ming Chiao Tung University, Hsinchu 300, Taiwan
| | - Chihpin Huang
- Institute of Environmental Engineering, National Yang-Ming Chiao Tung University, Hsinchu 300, Taiwan.
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Chang X, Wang Y, Li YX. Biomimetic mineralization of hydrated magnesium carbonate for hydrogel reinforcement and heavy metal adsorption. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 360:124644. [PMID: 39098641 DOI: 10.1016/j.envpol.2024.124644] [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: 06/09/2024] [Revised: 07/14/2024] [Accepted: 07/30/2024] [Indexed: 08/06/2024]
Abstract
With excessive Mn(Ⅱ) and Cu(Ⅱ) pollution in aquatic environments posing potential health risks to inhabitants, the emergence of carbon capture, utilization and storage (CCUS) technology has promoted the improvement of heavy metal remediation technologies. Using hydrothermal sediment as a crystal seed, rhamnolipid was used to mediate biomimetic mineralization to prepare hydrated magnesium carbonate (HMC) composites to enhance the Mn(Ⅱ)/Cu(Ⅱ) adsorption performance of alginate hydrogels. Hydrothermal sediment is beneficial for accelerating biomimetic mineralization, while rhamnolipid can induce a crystalline phase transformation from dypingite to nesquehonite. The addition of sediment significantly enhanced the compressive mechanical properties and thermal stability of the hydrogels. The adsorption performances of the nesquehonite and dypingite hydrogels were better for Mn(II) and Cu(II), respectively. An increase in the amount of sediment improved the adsorption of Cu(II) by the hydrogels appropriately, resulting in stronger selectivity for Cu(II). The adsorption of Mn(II) and Cu(II) on the hydrogel beads was thermodynamically spontaneous. The inhibitory effects of sodium dodecyl benzene sulfonate (SDBS), fulvic acid (FA) and alginate on Cu(II) adsorption were more obvious than those of bovine serum albumin (BSA). Both the complexation of functional groups on alginate and mineralization by HMC participated in the adsorption of Mn(II) and Cu(II).
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Affiliation(s)
- Xuan Chang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, Haidian District, Beijing, 100875, China
| | - Yang Wang
- College of Land Science and Technology, Key Laboratory of Arable Land Conservation (North China), Ministry of Agriculture, China Agricultural University, Beijing, 100193, China
| | - Ying-Xia Li
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, Haidian District, Beijing, 100875, China.
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Qian S, Shi F, Wang Z, Yu Y, Lu H, Jia Z, Ma J, Ma Y. Hydroxyl-aluminum pillared bentonite enhanced Mn(II) removal by chlorine oxidation. JOURNAL OF HAZARDOUS MATERIALS 2024; 476:135001. [PMID: 38908175 DOI: 10.1016/j.jhazmat.2024.135001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Revised: 06/09/2024] [Accepted: 06/20/2024] [Indexed: 06/24/2024]
Abstract
Al-PILC was used to catalyze the chlorine oxidation of Mn(II) in aqueous solution. The effects of various catalysts, catalyst dosage, chlorine dosage, pH value, temperature and organic content on the oxidation process were investigated. Results show that 1.5 mg/L chlorine can quickly oxidize Mn(II) from 0.5 mg/L to less than 0.04 mg/L with 10 mg/L Al-PILC. Using catalysts with higher porosity and higher SA, increase in chlorine concentration, increase in catalyst dosage, higher pH, and higher temperature can significantly enhance the rate of Mn(II) catalytic oxidation. The Mn(II) oxidation process includes the homogeneous oxidation, catalytic oxidation on the surface of the catalysts and self-catalytic oxidation produced by the newly produced MnOx. Al-PILC surface provides active sites for chlorine oxidation Mn(II) in the water, and also provides binding sites for the newly produced MnOx, which has higher catalytic activity and thus has an self-catalytic oxidation effect. The higher the porosity and SA of Al-PILC, the more catalytic oxidation active sites and loading sites, and the better the catalytic oxidation effect. The study promotes the understanding of chlorine catalyzed oxidation Mn(II) in aqueous solution, but also provide important guide to study newly efficient catalysts to oxidize Mn(II) with chlorine in aqueous solution.
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Affiliation(s)
- Sheng Qian
- College of Civil Engineering, Heilongjiang University, Harbin 150080, PR China; Engineering Research Center of Rural Water Safety of Heilongjiang Province, Heilongjiang University, Harbin 150080, PR China
| | - Fengmei Shi
- Heilongjiang Academy of Black Soil Conservation and Utilization, Heilongjiang Academy of Agricultural Sciences, Harbin 150086, PR China
| | - Zihao Wang
- College of Civil Engineering, Heilongjiang University, Harbin 150080, PR China
| | - Yifei Yu
- College of Civil Engineering, Heilongjiang University, Harbin 150080, PR China
| | - Hao Lu
- College of Civil Engineering, Heilongjiang University, Harbin 150080, PR China
| | - Zhen Jia
- College of Civil Engineering, Heilongjiang University, Harbin 150080, PR China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Yuxin Ma
- College of Civil Engineering, Heilongjiang University, Harbin 150080, PR China; Engineering Research Center of Rural Water Safety of Heilongjiang Province, Heilongjiang University, Harbin 150080, PR China.
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5
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Li C, Liu C, Xu W, Han Y, Gao Z, Bing Y, Li Q, Yu J. Control approach and evaluation framework of scaling in drinking water distribution systems: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 948:174836. [PMID: 39029761 DOI: 10.1016/j.scitotenv.2024.174836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Revised: 06/25/2024] [Accepted: 07/14/2024] [Indexed: 07/21/2024]
Abstract
The United Nations Sustainable Development Goals call for innovative proposals to ensure access to clean water and sanitation. While significant strides have been made in enhancing drinking water purification technologies, the role of drinking water distribution systems (DWDS) in maintaining water quality safety has increasingly become a focal point of concern. The presence of scale within DWDS can impede the secure and efficient functioning of the drinking water supply system, posing risks to the safety of drinking water quality. Previous research has identified that the primary constituents of scale in DWDS are insoluble minerals, such as calcium and magnesium carbonate. Elevated levels of hardness and alkalinity in the water can exacerbate scale formation. To address the scaling issue, softening technologies like induced crystallization, nanofiltration/reverse osmosis, and ion exchange are currently in widespread use. These methods effectively mitigate the scaling in DWDS by reducing the water's hardness and alkalinity. However, the application of softening technologies not only alters the hardness and alkalinity but also induces changes in the fundamental characteristics of water quality, leading to transition effects within the DWDS. This article reviews the impact of various softening technologies on the intrinsic properties of water quality and highlights the merits of electrochemical characteristic indicators in the assessment of water quality stability. Additionally, the paper delves into the factors that influence the transition effects in DWDS. It concludes with a forward-looking proposal to leverage artificial intelligence, specifically machine learning and neural networks, to develop an evaluation and predictive framework for the stability of drinking water quality and the transition effects observed in DWDS. This approach aims to provide a more accurate and proactive method for managing and predicting the impacts of water treatment processes on distribution system integrity and water quality over time.
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Affiliation(s)
- Changgeng Li
- Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes of Ministry of Education, Hohai University, Nanjing 210024, China; College of Environment, Hohai University, Nanjing 210024, China; School of Engineering and Built Environment, Griffith University, Brisbane, QLD 4111, Australia
| | - Cheng Liu
- Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes of Ministry of Education, Hohai University, Nanjing 210024, China; College of Environment, Hohai University, Nanjing 210024, China.
| | - Weibin Xu
- Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes of Ministry of Education, Hohai University, Nanjing 210024, China; College of Environment, Hohai University, Nanjing 210024, China
| | - Yun Han
- School of Engineering and Built Environment, Griffith University, Brisbane, QLD 4111, Australia; Queensland Micro- and Nanotechnology Centre, Griffith University, Brisbane, QLD 4111, Australia
| | - Zhipeng Gao
- Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes of Ministry of Education, Hohai University, Nanjing 210024, China; College of Environment, Hohai University, Nanjing 210024, China
| | - Yan Bing
- Jiangsu Heqinghaiyan Environment Co., LTD., Suqian 223815, China
| | - Qin Li
- School of Engineering and Built Environment, Griffith University, Brisbane, QLD 4111, Australia; Queensland Micro- and Nanotechnology Centre, Griffith University, Brisbane, QLD 4111, Australia
| | - Jimmy Yu
- School of Engineering and Built Environment, Griffith University, Brisbane, QLD 4111, Australia
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Qin X, Zhuang Y, Shi B. PFAS promotes disinfection byproduct formation through triggering particle-bound organic matter release in drinking water pipes. WATER RESEARCH 2024; 254:121339. [PMID: 38432003 DOI: 10.1016/j.watres.2024.121339] [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: 08/15/2023] [Revised: 02/11/2024] [Accepted: 02/17/2024] [Indexed: 03/05/2024]
Abstract
Loose deposit particles in drinking water distribution system commonly exist as mixtures of metal oxides, organic materials, bacteria, and extracellular secretions. In addition to their turbidity-causing effects, the hazards of such particles in drinking water are rarely recognized. In this study, we found that trace per- and polyfluoroalkyl substances (PFASs) could dramatically promote the formation of disinfection byproducts (DBPs) by triggering the release of particle-bound organic matter. Carboxylic PFASs have a greater ability to increase chloroacetic acid than sulfonic PFASs, and PFASs with longer chains have a greater ability to increase trichloromethane release than shorter-chain PFASs. Characterization by organic carbon and organic nitrogen detectors and Fourier transform ion cyclotron resonance mass spectrometry revealed that the released organic matter was mainly composed of proteins, carbohydrates, lignin, and condensed aromatic structures, which are the main precursors for the formation of DBPs, particularly highly toxic aromatic DBPs. After the release of organic matter, the particles exhibit a decrease in surface functional groups, an increase in surface roughness, and a decrease in particle size. The findings provide new insights into the risks of loose deposits and PFASs in drinking water, not only on PFASs per se but also on its effect of increasing toxic DBPs.
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Affiliation(s)
- Xinyi Qin
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuan Zhuang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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7
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Qi Z, Yu Y, Li G, Gao Y, Li P, Shi B. Reduced formation of brominated trihalomethanes during chlorination of bromide-containing waters in the presence of Mn(II). THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 920:171001. [PMID: 38365033 DOI: 10.1016/j.scitotenv.2024.171001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 01/27/2024] [Accepted: 02/13/2024] [Indexed: 02/18/2024]
Abstract
Manganese(II) (Mn(II)) and bromide (Br-) are common in natural waters. This study investigated the effect of in-situ Mn(II) oxidation and preformed MnOx on the brominated trihalomethane (Br-THM) formation during chlorination of bromide-containing waters. The results showed Br-THM formation could be substantially inhibited by in-situ Mn(II) oxidation, but the addition of preformed MnOx had limited influence on Br-THM formation during chlorination of bromide-containing waters. Analysis of bromine species showed that about 30 % bromine species were incorporated into the MnOx particles and formed MnOx-Br during the in-situ Mn(II) oxidation process. Consequently, the availability of reactive bromine species for the reaction with dissolved organic matter (DOM) reduced, leading to less Br-THM formation. X-ray diffraction (XRD) analysis of in-situ Mn(II) oxidation product indicated the presence of Br- decreased the crystallinity of Mn oxides, verifying the bromine species entered MnOx crystal. However, the adsorptive uptake of bromine species by preformed MnOx was negligible and had no impact on Br-THM formation. Inhibition rate of Mn(II) oxidation on THM formation decreased with increasing specific ultraviolet absorbance (SUVA254) value of filtered water, showing SUVA254 could be a good indicator of DOM competition ability for oxidant with Mn(II). In addition, Excitation/Emission Matrix indicated that Mn(II) could form complexes with humic substances, which might also retard the reaction between humic substances and oxidant to form Br-THMs. This study highlighted the inhibiting effect of in-situ Mn(II) oxidation on Br-THM formation during chlorination of bromide-containing waters.
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Affiliation(s)
- Zhenguo Qi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ying Yu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Guiwei Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Yujia Gao
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Penglu Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Zhang H, Zhang S, Liu Y, Yang M, Zhou X, Abbas G, Wang L, Lu J. Effects of chloride on corrosion scale compositions and heavy metal release in drinking water distribution systems. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133452. [PMID: 38198869 DOI: 10.1016/j.jhazmat.2024.133452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 12/16/2023] [Accepted: 01/03/2024] [Indexed: 01/12/2024]
Abstract
Variations in water chemistry may lead to the release of harmful heavy metals in drinking water distribution systems (DWDSs). In this study, the effects of chloride on the release of heavy metals such as Fe, Mn, As, Cr, Mo, V, Sr, and Co were examined using steel and cast iron pipe loops. After chloride was added, the relative contents of goethite (α-FeOOH), lepidocrocite (γ-FeOOH), and siderite (FeCO3) in pipe scales increased, but the contents of magnetite (Fe3O4) decreased. The most prevalent compounds were α-FeOOH and γ-FeOOH. When the chloride levels were increased, the effluent concentrations of Fe, Mn, As, Cr, Mo, V, Sr, and Co significantly increased. These heavy metals were released presumably because of the destabilization and dissolution of corrosion scales induced by chloride and adsorption site competition. Strong positive correlations were also observed between Fe&Mn, Fe/Mn&As, Fe/Mn&Cr, Fe/Mn&Mo, Fe/Mn&V, Fe/Mn&Sr, and Fe/Mn&Co, indicating the co-release of Fe, Mn, and other metals. This study may be helpful for the potential strategies on avoidance of heavy metal release and improvement of water supply security.
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Affiliation(s)
- Hui Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Shan Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Yuekai Liu
- Qingdao Municiple Engineering Design & Research Institute, Qingdao 266000, PR China
| | - Min Yang
- China Northwest Architecture Design and Research Institute Co. Ltd, Xi'an 710018, PR China
| | - Xue Zhou
- Shenzhen Water Resources Planning and Design Institute Co., Ltd, Shenzhen 518000, PR China
| | - Ghulam Abbas
- Department of Chemical Engineering and Technology, University of Gujrat, Gujrat 50700, Pakistan
| | - Long Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Jinsuo Lu
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, PR China.
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Li G, Chen Q, Wang H, Su Y, Wu B, Yu J, Yang M, Shi B. Corroded iron pipe inhibits microbial-mediated Mn(II) oxidation and MnO x accumulation compared to PVC pipe. WATER RESEARCH 2024; 251:121142. [PMID: 38246084 DOI: 10.1016/j.watres.2024.121142] [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: 09/24/2023] [Revised: 01/09/2024] [Accepted: 01/14/2024] [Indexed: 01/23/2024]
Abstract
MnOx deposits in distribution pipes can cause severe discoloration problems in drinking water. However, the impact of pipe materials on Mn(II) oxidation and MnOx accumulation remains unclear. This study investigated microbial-mediated Mn(II) oxidation and deposit formation through 300-day pipe loop experiments with corroded galvanized steel pipes (DN100) and new polyvinyl chloride (PVC) pipes (DN100). The results showed that influent Mn(II) was entirely oxidized within 48 h in the PVC pipes with biofilms in the absence of chlorine, while most influent Mn(II) remained unoxidized in the iron pipes. Dissolved oxygen (DO) monitoring showed that the DO in the PVC pipes was consistently higher than 8.0 mg/L, but that in the iron pipes dropped to 6.5 mg/L. Microbial analysis revealed that the abundance of potential Mn(II)-oxidizing bacteria in the low-DO iron pipes was less than that in the PVC pipes. Analysis of the Mn(II) concentration dynamics in different pipes revealed that the early Mn(II) disappearance in the iron pipes was contributed mainly to Mn(II) adsorption by iron corrosion products rather than microbial Mn(II) oxidation. When aeration was performed to increase the DO concentration to 8.0 mg/L in the iron pipes, complete Mn(II) oxidation occurred. This study provides insights into Mn(II) transformation in different pipes and highlights the critical role of DO in microbial Mn(II) oxidation in drinking water pipes.
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Affiliation(s)
- Guiwei Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Qi Chen
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Institute of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou, Henan 450045, China
| | - Haibo Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yuliang Su
- Zhuhai Water Environment Holdings Group Ltd., Zhuhai, Guangdong 519000, China
| | - Bin Wu
- Zhuhai Water Environment Holdings Group Ltd., Zhuhai, Guangdong 519000, China
| | - Jianwei Yu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Min Yang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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10
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Niu J, Chen D, Shang C, Xiao L, Wang Y, Zeng W, Zheng X, Chen Z, Du X, Chen X. Niche Differentiation of Biofilm Microorganisms in a Full-scale Municipal Drinking Water Distribution System in China and Their Implication for Biofilm Control. MICROBIAL ECOLOGY 2023; 86:2770-2780. [PMID: 37542538 DOI: 10.1007/s00248-023-02274-y] [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: 04/28/2023] [Accepted: 07/21/2023] [Indexed: 08/07/2023]
Abstract
Biofilms on the inner surface of a drinking water distribution system (DWDS) affect water quality and stability. Understanding the niche differentiation of biofilm microbial communities is necessary for the efficient control of DWDS biofilms. However, biofilm studies are difficult to conduct in the actual DWDS because of inaccessibility to the pipes buried underground. Taking the opportunity of infrastructure construction and relevant pipeline replacement in China, biofilms in a DWDS (a water main and its branch pipes) were collected in situ, followed by analysis on the abundances and community structures of bacterial and archaeal using quantitative PCR and high-throughput sequencing, respectively. Results showed that archaea were detected only in the biofilms of the water main, with a range of 9.4×103~1.1×105 copies/cm2. By contrast, bacteria were detected in the biofilms of branch pipes and the distal part of the water main, with a range of 8.8×103~9.6×106 copies/cm2. Among the biofilm samples, the archaeal community in the central part of the water main showed the highest richness and diversity. Nitrosopumilus was found to be predominant (86.22%) in the biofilms of the proximal part of the water main. However, Methanobrevibacter (87.15%) predominated in the distal part of the water main. The bacterial community of the water main and branch pipes was primarily composed of Firmicutes and Proteobacteria at the phylum level, respectively. Regardless of archaea or bacteria, only few operational taxonomic units (OTUs) (<0.5% of total OTUs) were shared by all the biofilms, indicating the niche differentiation of biofilm microorganisms. Moreover, the high Mn content in the biofilms of the distal sampling location (D3) in the water main was linked to the predominance of Bacillus. Functional gene prediction revealed that the proportion of infectious disease-related genes was 0.44-0.67% in the tested biofilms. Furthermore, functional genes related to the resistance of the bacterial community to disinfections and antibiotics were detected in all the samples, that is, glutathione metabolism-relating genes (0.14-0.65%) and beta-lactam resistance gene (0.01-0.05%). The results of this study indicate the ubiquity of archaea and bacteria in the biofilms of water main and branch pipes, respectively, and pipe diameters could be a major influencing factor on bacterial community structure. In the water main, the key finding was the predominant existence of archaea, particularly Nitrosopumilus and methanogen. Hence, their routine monitoring and probable influences on water quality in pipelines with large diameter should be given more attention. Besides, since Mn-related Bacillus and suspected pathogenic Enterococcus were detected in the biofilm, supplementation of disinfectant may be a feasible strategy for inhibiting their growth and ensuring water quality. In addition, the monitoring on their abundance variation could help to determine the frequency and methods of pipeline maintenance.
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Affiliation(s)
- Jia Niu
- Center of Safe and Energy-saving Engineering Technology for Urban Water Supply and Drainage System, School of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, 350118, People's Republic of China
| | - Daogan Chen
- Center of Safe and Energy-saving Engineering Technology for Urban Water Supply and Drainage System, School of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, 350118, People's Republic of China
| | - Chenghao Shang
- Center of Safe and Energy-saving Engineering Technology for Urban Water Supply and Drainage System, School of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, 350118, People's Republic of China
| | - Liang Xiao
- Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology, College of Environment and Safety Engineering, Fuzhou University, Fuzhou, 350108, People's Republic of China
| | - Yue Wang
- Fuzhou Water Supply Company, Fuzhou, Fujian, 350001, People's Republic of China
| | - Wuqiang Zeng
- Center of Safe and Energy-saving Engineering Technology for Urban Water Supply and Drainage System, School of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, 350118, People's Republic of China
| | - Xianliang Zheng
- Center of Safe and Energy-saving Engineering Technology for Urban Water Supply and Drainage System, School of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, 350118, People's Republic of China
| | - Ziyi Chen
- Center of Safe and Energy-saving Engineering Technology for Urban Water Supply and Drainage System, School of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, 350118, People's Republic of China
| | - Xupu Du
- Center of Safe and Energy-saving Engineering Technology for Urban Water Supply and Drainage System, School of Ecological Environment and Urban Construction, Fujian University of Technology, Fuzhou, Fujian, 350118, People's Republic of China
| | - Xiaochen Chen
- Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology, College of Environment and Safety Engineering, Fuzhou University, Fuzhou, 350108, People's Republic of China.
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11
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Qian X, Wang S, Cheng H, Jia Z, Wang D, Xie Y, Duan J, Tian Y, Ma J. Mn(II) oxidation by the UV/chlorine system under near-neutral pH conditions: The important role of ClO · and ClO 2. WATER RESEARCH 2023; 246:120673. [PMID: 37844341 DOI: 10.1016/j.watres.2023.120673] [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: 05/30/2023] [Revised: 09/11/2023] [Accepted: 09/25/2023] [Indexed: 10/18/2023]
Abstract
The oxidation kinetics of Mn(II) by free chlorine is relatively low under near-neutral pH conditions which limits the Mn removal efficiency in drinking water treatment. Therefore, this study investigated the oxidation efficiency of Mn(II) by the UV-enhanced chlorination (UV/chlorine) system and identified the responsible reactive radical species. The results show that the oxidation kinetic of Mn(II) was greatly enhanced by the UV/chlorine system under near-neutral pH or even acidic conditions. The pseudo-first-order reaction rate of Mn(II) at pH 8.0 (within the first 20 min) increased from 2.60 × 10-5 s-1 to 3.41 × 10-4 s-1. Based on the scavenging experiments and the steady-state kinetic modeling, ClO· and ClO2, whose steady-state concentration (∼10-10 M and ∼10-9 M, respectively at pH 8.0) was at least 4 orders of magnitude higher than that of HO· and Cl·, were recognized as the dominant reactive species contributing to the oxidation of Mn(II). Kinetic model calculations indicate that the contribution of ClO· to the oxidation of Mn(II) was consistently maintained above 70 %, and ClO2 also played an important role in the oxidation of Mn(II) especially under acidic and alkaline conditions. In addition, the background components of HCO3- and Cl- had negligible influence on the oxidation efficiency because they barely changed the concentration of the ClO· and ClO2. This study first demonstrates the important role of ClO2 in the oxidation of Mn(II) in the UV/chlorine system, and the possible role of ClO2 in the degradation of some organic pollutants needs to be carefully evaluated in the future.
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Affiliation(s)
- Xuecong Qian
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Shilong Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Haijun Cheng
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Ziye Jia
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Da Wang
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310032, China
| | - Yandong Xie
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jinhao Duan
- College of New Energy and Environment, Jilin University, Changchun 130021, China
| | - Yu Tian
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
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12
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McCormick NE, Earle M, Kent A, Ha C, Hakes L, Anderson L, Stoddart AK, Langille MGI, Gagnon GA. Betaproteobacteria are a key component of surface water biofilters that maintain sustained manganese removal in response to fluctuations in influent water temperature. WATER RESEARCH 2023; 244:120515. [PMID: 37634461 DOI: 10.1016/j.watres.2023.120515] [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: 03/15/2023] [Revised: 08/09/2023] [Accepted: 08/20/2023] [Indexed: 08/29/2023]
Abstract
The health risks associated with manganese (Mn) in drinking water, and an improved understanding of Mn accumulation within, and subsequent release from, distribution systems, have increased the need for robust, sustainable treatment options to minimize Mn concentrations in finished water. Biofiltration is an established and effective method to remove Mn in groundwater however, Mn removal in surface water biofilters is an emerging treatment process that has not been extensively studied. Seasonal variations in water temperature can present an operational challenge for surface water biofilters which may see reduced Mn removal under colder conditions. This study examined the microbiomes of surface water biofilters at three utilities (ACWD WTP, WTP B, and WTP D) which all experienced similar seasonal fluctuations in influent water temperature. High Mn removal was observed at the ACWD WTP for much of the year, but Mn removal decreased with a concurrent decrease in the influent water temperature (58% ± 22%). In contrast, both WTP B and WTP D achieved year-round Mn removal (84% ± 5% and 93% ± 8% respectively). Marker gene (16S rRNA) sequencing analysis of the biofilter microbiomes identified a high abundance of Betaproteobacteria in WTP B and WTP D (37% ± 12% and 21% ± 3% respectively), but a low abundance of Betaproteobacteria in the ACWD WTP (2% ± 2%). The microbiomes of new bench-scale biofilters, in operation at the ACWD WTP, were also investigated. The abundance of Betaproteobacteria was significantly greater (p < 0.05) after the biofilters had acclimated than before acclimation, and differential abundance analysis identified 6 genera within the Betaproteobacteria class were enriched in the acclimated microbiome. Additionally, the acclimated biofilters were able to maintain high Mn removal performance (87% ± 10%) when the influent water temperature decreased to 10 °C or less. Further analysis of previously published studies found the abundance of Betaproteobacteria was also significantly greater (p < 0.001) in biofilters with sustained Mn removal than in biofilters which did not treat for Mn as a contaminant, despite differences in design scale, source water, and media type. Microbiome network analysis identified multiple co-occurrence relationships between Betaproteobacteria and Mn oxidizing bacteria in the WTP B and WTP D biofilters, suggesting indirect contributions by Betaproteobacteria to biological Mn oxidation. These co-occurrence relationships were not present in the full-scale ACWD WTP microbiome. Whether the role of Betaproteobacteria in biological Mn oxidation is direct, indirect, or a combination of both, they are consistently present at a high abundance in both groundwater and surface water biofilters with sustained Mn removal, and their absence may contribute to the seasonal fluctuations in Mn removal observed at the ACWD WTP. This new insight to Betaproteobacteria and their role in Mn biofiltration could contribute to water innovation and design that would improve the reliability of Mn removal.
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Affiliation(s)
- N E McCormick
- Centre for Water Resources Studies, Department of Civil and Resource Engineering, Dalhousie University, Halifax, NS, Canada.
| | - M Earle
- Centre for Water Resources Studies, Department of Civil and Resource Engineering, Dalhousie University, Halifax, NS, Canada
| | - A Kent
- Arcadis US, Inc., Austin, TX, USA
| | - C Ha
- Alameda County Water District, Freemont, CA, USA
| | - L Hakes
- Alameda County Water District, Freemont, CA, USA
| | - L Anderson
- Centre for Water Resources Studies, Department of Civil and Resource Engineering, Dalhousie University, Halifax, NS, Canada
| | - A K Stoddart
- Centre for Water Resources Studies, Department of Civil and Resource Engineering, Dalhousie University, Halifax, NS, Canada
| | - M G I Langille
- Department of Pharmacology, Dalhousie University, Halifax, NS, Canada
| | - G A Gagnon
- Centre for Water Resources Studies, Department of Civil and Resource Engineering, Dalhousie University, Halifax, NS, Canada
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13
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Gao Y, Zhuang Y, Wu S, Qi Z, Li P, Shi B. Enhanced disinfection byproducts formation by fine iron particles intercepted in household point-of-use facilities. WATER RESEARCH 2023; 243:120320. [PMID: 37454460 DOI: 10.1016/j.watres.2023.120320] [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: 04/15/2023] [Revised: 07/03/2023] [Accepted: 07/04/2023] [Indexed: 07/18/2023]
Abstract
To cope with the demand for good-quality potable water, household point-of-use (POU) facilities such as polypropylene cotton filters (PCFs) are widely used. However, the behaviors of new and used PCFs under discoloration are unclear. In this study, we found that new PCF did not effectively intercept particles under discoloration within the initial 5 d of inflow. In addition, the particles, especially the fine ones, accumulated in the long-used PCF exacerbated the risks of disinfection byproducts (DBPs) and microbes. The concentrations of trihalomethanes (THMs) and haloacetonitriles (HANs) in the effluent run through the PCF all increased over time; interestingly, all sharply increased after 5 d in accordance with the decrease in effluent iron particles. During this stage, maximum increases rate of 117.89% in THMs and 75.12% in HANs were observed. For haloacetic acids (HAAs), it served as the dominant contaminants, with concentrations approximately 10-fold greater than those of THMs and HANs. The increase showed that used PCFs could exacerbate the risks in DBPs exposure. Adenosine triphosphate (ATP) also showed a similar trend, with a maximum increase from 0.0033 to 0.0055 nmol/mL. Thus, PCFs can act only as pretreatment units and should be replaced after yellow water events. This study offers important guidance for PCF usage in drinking water purification, especially under discoloration.
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Affiliation(s)
- Yujia Gao
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yuan Zhuang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Shuxuan Wu
- College of Water Sciences, Beijing Normal University, Beijing 100875, China
| | - Zhenguo Qi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Penglu Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
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14
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Aiken M, Ying SC. Small Community Water Systems Have the Highest Prevalence of Mn in Drinking Water in California, USA. ACS ES&T WATER 2023; 3:2168-2178. [PMID: 37588804 PMCID: PMC10425977 DOI: 10.1021/acsestwater.3c00007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 04/12/2023] [Accepted: 04/13/2023] [Indexed: 08/18/2023]
Abstract
Manganese (Mn) is currently regulated as a secondary contaminant in California, USA; however, recent revisions of the World Health Organization drinking water guidelines have increased regulatory attention of Mn in drinking water due to increasing reports of neurotoxic effects in infants and children. In this study, Mn concentrations reported to California's Safe Drinking Water Information System were used to estimate the potentially exposed population within California based on system size. We estimate that between 2011 and 2021, over 525,000 users in areas with reported Mn data are potentially exposed to Mn concentrations exceeding the WHO health-based guideline (80 μg L-1), and over 34,000 users are potentially exposed to Mn concentrations exceeding the U.S. Environmental Protection Agency health-advisory limit (300 μg L-1). Water treatment significantly decreased Mn concentrations compared to intake concentrations for all system sizes. However, smaller water systems have a wider range and a higher skew of Mn concentrations in finished water than larger systems. Additionally, higher Mn concentrations were found in systems above the maximum contaminant levels for chromium and arsenic. The treatment of these primary contaminants appears to also remove Mn. Lastly, data missingness remains a barrier to accurately assess public exposure to Mn in very small, small, and medium community water system-delivered water.
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Affiliation(s)
- Miranda
L. Aiken
- School
of Earth and Environmental Sciences, Schmid College of Science and
Technology, Chapman University, Orange, California 92866, United States
| | - Samantha C. Ying
- Schmid
College of Science and Technology, Chapman
University, Orange, California 92866, United States
- Environmental
Sciences Department, University of California, Riverside, California 92521, United States
- Planetary
Health Center, University of California
Global Health Institute, San Francisco, California, 94158, United States
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15
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Chen Q, Li G, Lu Z, Su Y, Wu B, Shi B. Efficient Mn(II) removal by biological granular activated carbon filtration. JOURNAL OF HAZARDOUS MATERIALS 2023:131877. [PMID: 37344241 DOI: 10.1016/j.jhazmat.2023.131877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 06/06/2023] [Accepted: 06/15/2023] [Indexed: 06/23/2023]
Abstract
Sufficient and sustainable manganese(II) removal is a challenging task to prevent Mn-related drinking water discoloration problems. This study investigated Mn(II) removal by granular activated carbon (GAC) filtration under various conditions. The results showed that biological GAC filter columns could reduce Mn(II) from 400 μg/L to 10 μg/L after a short ripening period, while sand filter columns did not show evident Mn(II) removal function. Water quality changes, pretreatment with NaClO and chemogenic MnOx coating on GAC media surface did not influence the Mn(II) removal capacity of GAC filter columns. 16S rRNA gene sequencing showed that the abundance of potential Mn(II)-oxidizing bacteria in the GAC media was similar to that in the sand media. However, qPCR results indicated that GAC media colonized dramatically more biomass than sand media, resulting in highly effective Mn(II) removal by GAC filter columns. Under chlorinated conditions, GAC filtration underperformed sand filtration in Mn(II) removal, although activated carbon has been reported to be capable of catalyzing Mn(II) oxidation by chlorine. Fast chlorine decay in GAC filter columns made it hard to sustain chemical Mn(II) oxidation and thus led to less Mn(II) removal. This study highlighted the advantage of biological GAC filtration over sand filtration in Mn(II) removal.
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Affiliation(s)
- Qi Chen
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Institute of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450045, China
| | - Guiwei Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Zhili Lu
- Institute of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450045, China
| | - Yuliang Su
- Zhuhai Water Environment Holdings Group Ltd., Zhuhai, Guangdong 519000, China
| | - Bin Wu
- Zhuhai Water Environment Holdings Group Ltd., Zhuhai, Guangdong 519000, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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16
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Dong F, Zhu J, Li J, Fu C, He G, Lin Q, Li C, Song S. The occurrence, formation and transformation of disinfection byproducts in the water distribution system: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 867:161497. [PMID: 36634528 DOI: 10.1016/j.scitotenv.2023.161497] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 01/02/2023] [Accepted: 01/05/2023] [Indexed: 06/17/2023]
Abstract
Disinfection is an effective process to inactivate pathogens in drinking water treatment. However, disinfection byproducts (DBPs) will inevitably form and may cause severe health concerns. Previous research has mainly focused on DBPs formation during the disinfection in water treatment plants. But few studies paid attention to the formation and transformation of DBPs in the water distribution system (WDS). The complex environment in WDS will affect the reaction between residual chlorine and organic matter to form new DBPs. This paper provides an overall review of DBPs formation and transformation in the WDS. Firstly, the occurrence of DBPs in the WDS around the world was cataloged. Secondly, the primary factors affecting the formation of DBPs in WDS have also been summarized, including secondary chlorination, pipe materials, biofilm, deposits and coexisting anions. Secondary chlorination and biofilm increased the concentration of regular DBPs (e.g., trihalomethanes (THMs) and haloacetic acids (HAAs)) in the WDS, while Br- and I- increased the formation of brominated DBPs (Br-DBPs) and iodinated DBPs (I-DBPs), respectively. The mechanism of DBPs formation and transformation in the WDS was systematically described. Aromatic DBPs could be directly or indirectly converted to aliphatic DBPs, including ring opening, side chain breaking, chlorination, etc. Finally, the toxicity of drinking water in the WDS caused by DBPs transformation was examined. This review is conducive to improving the knowledge gap about DBPs formation and transformation in WDS to better solve water supply security problems in the future.
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Affiliation(s)
- Feilong Dong
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Jiani Zhu
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Jinzhe Li
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Chuyun Fu
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Guilin He
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan 250101, China
| | - Qiufeng Lin
- Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, United States
| | - Cong Li
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200433, China
| | - Shuang Song
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China.
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17
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Zhang S, Zhao W, Jia S, Wei L, Zhou L, Tian Y. Study on release and occurrence of typical metals in corrosion products of drinking water distribution systems under stagnation conditions. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:15217-15229. [PMID: 36166128 DOI: 10.1007/s11356-022-23151-0] [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: 04/06/2022] [Accepted: 09/17/2022] [Indexed: 06/16/2023]
Abstract
Metal contaminants in corrosion products of drinking water distribution systems (DWDS) can be released into potable water under specific conditions, thereby polluting drinking water and posing a health risk. Under stagnation conditions, the release characteristics, occurring forms, and environmental risks of ten metals were determined in loose and tubercle scale solids of an unlined cast iron pipe with a long service history, before and after immersion. Most Al, As, Cr, Fe, and V in corrosion scales existed in the residual fraction, with the released concentration and pollution risk being low. Since more than 59% of Ca in pipe scales existed in the exchangeable fraction, Ca release was high. Although the Pb and Cd content of corrosion solids was low, a high proportion of Pb and Cd was present in non-residual fractions with high mobility. Sudden severe Pb or Cd pollution events in DWDS could result in high pollution and environmental risk levels. The total content and released amount of Mn and Zn in corrosion scales were both high. Therefore, while special attention should be paid to Mn and Zn, Pb and Cd also present a high risk in pipe scales, despite their low concentrations. During stagnation immersion, metal release from powdered pipe scales occurred via the processes of mass release, re-adsorption into scales, and slow release until equilibrium was reached. The levels of metal re-adsorption into scales were much higher than the concentrations dissolved into bulk water. However, the amount of metal re-adsorption into tubercle scale blocks was less. Importantly, these findings highlight that during DWDS operation, the sudden release of metal pollutants caused by pipe scale breakage should be avoided.
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Affiliation(s)
- Shengnan Zhang
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Tianjin, 300350, Jinnan District, China
- Tianjin Renai College, Tianjin, 301636, China
| | - Weigao Zhao
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Tianjin, 300350, Jinnan District, China
| | - Shichao Jia
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Tianjin, 300350, Jinnan District, China
| | - Lianyi Wei
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Tianjin, 300350, Jinnan District, China
| | - Letong Zhou
- Tianjin Renai College, Tianjin, 301636, China
| | - Yimei Tian
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Tianjin, 300350, Jinnan District, China.
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18
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He W, Zheng S, Chen X, Lu D, Zeng Z. Alkaline aging significantly affects Mn(II) adsorption capacity of polypropylene microplastics in water environments: Critical roles of natural organic matter and colloidal particles. JOURNAL OF HAZARDOUS MATERIALS 2022; 438:129568. [PMID: 35999752 DOI: 10.1016/j.jhazmat.2022.129568] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 07/07/2022] [Accepted: 07/08/2022] [Indexed: 06/15/2023]
Abstract
Most microplastic particles may undergo various aging in water environments. In this work, surface physicochemical properties were firstly compared among pristine polypropylene (PP-pris) microplastics, and two aged ones obtained after pretreated with HCl (PP-acid) and NaOH (PP-alka). When compared with PP-pris and PP-acid, PP-alka had a much stronger Mn(II) adsorption capacity. The results regarding the role of natural organic matter and colloidal particle concentrations on adsorption demonstrated that for water solutions either containing kaolin or not, humic acid (HA) had significantly negative influence on Mn(II) adsorption capacity of PP-alka due to their complexation and competition effects, and its negative influence became enhanced with increasing kaolin concentrations. Besides, established conceptual models of adsorption were applied to comprehensively explore adsorption mechanisms of PP-alka for Mn(II) in the coexistence of HA and kaolin. An important suggestion was that in complicated adsorption-reactor system, great numbers of microplastics-kaolin heteroaggregates might be formed via ion bridging of Mn(II) and/or polymer bridging of HA. So these formed aggregates were possible to re-organize themselves, under pre-set vibration-speed conditions, for achieving a more stable structure. As a consequence, Mn(II) adsorption behaviors would be affected by changes in steric-hindrance effects of HA molecules and surface charge distribution of resultant heteroaggregates.
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Affiliation(s)
- Weipeng He
- Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Building Safety and Energy Efficiency (Ministry of Education), College of Civil Engineering, Hunan University, Changsha 410082, PR China.
| | - Sa Zheng
- Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Building Safety and Energy Efficiency (Ministry of Education), College of Civil Engineering, Hunan University, Changsha 410082, PR China
| | - Xingqi Chen
- Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Building Safety and Energy Efficiency (Ministry of Education), College of Civil Engineering, Hunan University, Changsha 410082, PR China
| | - Danjing Lu
- Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Building Safety and Energy Efficiency (Ministry of Education), College of Civil Engineering, Hunan University, Changsha 410082, PR China
| | - Zihe Zeng
- Hunan Engineering Research Center of Water Security Technology and Application, College of Civil Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Building Safety and Energy Efficiency (Ministry of Education), College of Civil Engineering, Hunan University, Changsha 410082, PR China
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19
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Tian Y, Peng Z, Liu Y, Jia S, Shen H, Zhao W. Characteristics of vanadium release from layered steel pipe scales to bulk, steady, and occluded water in drinking water distribution systems. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156465. [PMID: 35660623 DOI: 10.1016/j.scitotenv.2022.156465] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/23/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
The release of vanadium (V) from drinking water distribution systems (DWDS) can endanger water quality and human health. Therefore, in this study, the physicochemical characteristics of old steel pipe scales were analyzed, and dynamic pipeline devices were constructed. Subsequently, static release experiments were conducted to find an optimum scale-water ratio and investigate the release behaviors of V in lumpy pipe scales. Besides, the release behaviors of V from layered pipe scales to bulk, steady, and occluded water under the combined effect of multiple water quality conditions were studied for the first time. Computational fluid dynamics (CFD) was adopted to explain the release behaviors of V in the dynamic pipeline. Results revealed that the adsorption performance of the layered scales decreased in the order of surface layer > porous core layer > hard shell-like layer. The release behaviors of V in the lumpy pipe scales were mainly divided into rapid desorption and colloidal agglomeration stages. The Double constant and Weber-Morris models can suitably describe release stage I (R2 > 0.919) and release stage II (R2 > 0.948), respectively. Notably, the release of V was aggravated by low pH, high temperature, and high SO42- concentration, and the release amount of V in the pipeline was more significant than the layered pipe scales. Steady water in the gaps of scales contained more V than bulk water, and the malignant occluded water encased in scales contained relatively low V concentrations. In short, the main mechanism of V release was competitive adsorption in the early stage, and pH was the main influencing factor in the later stage. The above results are of great significance for revealing the release behaviors of V and reducing its release in DWDS.
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Affiliation(s)
- Yimei Tian
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin 300350, China
| | - Zhu Peng
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin 300350, China
| | - Yunhui Liu
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin 300350, China
| | - Shichao Jia
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin 300350, China
| | - Hailiang Shen
- Computational Hydraulics International, 147 Wyndham St. N., Ste. 202, Guelph, Ontario, Canada
| | - Weigao Zhao
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin 300350, China.
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20
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Li G, Su Y, Wu B, Chen Q, Yu J, Yang M, Shi B. Chloramine Prevents Manganese Accumulation in Drinking Water Pipes Compared to Free Chlorine by Simultaneously Inhibiting Abiotic and Biotic Mn(II) Oxidation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:12278-12287. [PMID: 35976066 DOI: 10.1021/acs.est.2c03203] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The oxidation of residual Mn(II) in finished water can lead to MnOx deposit formation in drinking water pipes. Previous work has illustrated that microbes readily cause Mn deposit build-up in nondisinfected pipes. Here, we investigated how disinfectant type and dose affected Mn(II) oxidation and MnOx accumulation through long-term pipe experiments using water produced by a full-scale water treatment plant. The results showed that Mn(II) oxidation initiated quickly in the new pipes chlorinated with 1.0 mg/L free chlorine. After 130 days of MnOx accumulation, 100 μg/L Mn(II) in water could drop to 1.0 μg/L within 1.5 h, resulting from autocatalytic Mn(II) oxidation and Mn(II) adsorption by MnOx deposits accumulated on pipe walls. In contrast to chlorination, chloramination (1.0 mg/L Cl2) caused almost no MnOx accumulation during the entire study period. The underlying mechanism was probably that monochloramine inhibited microbial Mn(II) oxidation without causing significant abiotic Mn(II) oxidation like free chlorine. A low free chlorine dose (0.3 mg/L) also reduced Mn deposit formation by mass but to a lesser extent than chloramination. After disinfection (chlorination or chloramination) was discontinued for days, biotic Mn(II) oxidation occurred, and this process was inhibited again once disinfection was resumed. In addition, Fe(III) of 200 μg/L enhanced the stability of MnOx accumulated on pipe surfaces, while humic acid induced MnOx deposit resuspension. Overall, this study highlighted the regulating role of disinfectants in MnOx formation and provided insights into developing appropriate disinfection strategies for Mn deposit control.
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Affiliation(s)
- Guiwei Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yuliang Su
- Zhuhai Water Environment Holdings Group Ltd., Zhuhai 519000, Guangdong, China
| | - Bin Wu
- Zhuhai Water Environment Holdings Group Ltd., Zhuhai 519000, Guangdong, China
| | - Qi Chen
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Jianwei Yu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Min Yang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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21
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Li G, Zhao Y, An G, Shi B. Mn(II) Oxidation by Free Chlorine Catalyzed by the Hydrolytic Products of Ferric and Aluminum Species under Drinking Water Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:10775-10784. [PMID: 35876009 DOI: 10.1021/acs.est.2c02323] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Mn(II) oxidation by free chlorine can be applied to remove Mn(II) at water treatment plants. This reaction also results in particulate MnOx formation and accumulation in drinking water distribution systems. This study investigated the effect of Fe(III) and Al(III) hydrolysis products (mainly precipitates) on Mn(II) oxidation by free chlorine under drinking water conditions. The results showed that Fe3+ added as FeCl3 and Al(III) added as polyaluminum chloride (PACl) at tens to hundreds of micrograms per liter dramatically catalyzed Mn(II) oxidation by free chlorine. Through hydrolytic precipitation at circumneutral pH, Fe3+ and Al13 (the dominant preformed Al species in PACl) generated Fe(OH)3-like particles and Al13 aggregates, respectively, which initiated heterogeneous Mn(II) oxidation. Kinetic modeling indicated that, once some MnOx was formed, MnOx and Fe(OH)3 catalyzed the subsequent Mn(II) oxidation to an equal extent. The particles (aggregates) formed from Al13 species exhibited a weaker catalytic capacity in comparison to MnOx and Fe(OH)3 at equivalent molar concentrations. Interestingly, unlike Al13 species in PACl, Al(III) added as AlCl3 had a negligible influence on Mn(II) oxidation, even when Al(OH)3(am) precipitates were formed. The catalytic effects of Fe3+ and Al13 hydrolysis products were confirmed by experiments with natural water and finished water, and the lower Mn(II) oxidation rate was mainly attributed to organic matter.
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Affiliation(s)
- Guiwei Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Yuanyuan Zhao
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Guangyu An
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
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22
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Li G, Su Y, Wu B, Han G, Yu J, Yang M, Shi B. Initial Formation and Accumulation of Manganese Deposits in Drinking Water Pipes: Investigating the Role of Microbial-Mediated Processes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:5497-5507. [PMID: 35420026 DOI: 10.1021/acs.est.1c08293] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Microbial Mn(II) oxidation occurs in areas with insufficient disinfectants in drinking water distribution systems. However, the overall processes of microbial-mediated Mn deposit formation are unclear. This research investigated the initial Mn(II) oxidation, deposit accumulation, and biofilm development in pipe loops fed with nondisinfected finished water for 300 days. The results show that it took 20 days for microbial Mn(II) oxidation and deposition to be initiated visibly in new pipes continuously receiving 100 μg/L Mn(II). Once started, the deposit accumulation accelerated. A pseudo-first-order kinetic model could simulate the disappearance of Mn(II) in well-mixed pipe loop water. The observed rate constant reached 2.81 h-1 [corresponding to a Mn(II) half-life of 0.25 h] after 136 days of operation. Without oxygen, Mn(II) in the water also decreased rapidly to 1.0 μg/L through adsorption to deposits, indicating that after the initial microbial formation of MnOx, subsequent MnOx accumulation was attributable to a combination of microbial and physicochemical processes. Compared to the no-Mn condition, Mn(II) input resulted in 1 order of magnitude increase in biofilm formation. This study sheds light on the increasingly rapid processes of Mn accumulation on the inner surfaces of water pipes resulting from the biological activity of Mn(II)-oxidizing biofilms and the build-up of MnOx with strong adsorption capacity.
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Affiliation(s)
- Guiwei Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yuliang Su
- Zhuhai Water Environment Holdings Group Ltd., Zhuhai, Guangdong 519000, China
| | - Bin Wu
- Zhuhai Water Environment Holdings Group Ltd., Zhuhai, Guangdong 519000, China
| | - Guohang Han
- Zhuhai Water Environment Holdings Group Ltd., Zhuhai, Guangdong 519000, China
| | - Jianwei Yu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Min Yang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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Kurajica L, Ujević Bošnjak M, Kinsela AS, Bieroza M, Štiglić J, Waite TD, Capak K, Romić Ž. Mixing of arsenic-rich groundwater and surface water in drinking water distribution systems: Implications for contaminants, disinfection byproducts and organic components. CHEMOSPHERE 2022; 292:133406. [PMID: 34958791 DOI: 10.1016/j.chemosphere.2021.133406] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 12/17/2021] [Accepted: 12/21/2021] [Indexed: 06/14/2023]
Abstract
The utilization of groundwaters containing high levels of arsenic (As) for drinking water purposes presents major health and economic challenges for water utilities. One low-cost approach is to mix arsenic-rich groundwater (GW) with arsenic-free surface waters (SW) to achieve acceptable As levels. In this study we investigated the effect of different mixing ratios on water quality in an eastern Croatian water distribution system (WDS). To investigate the effects of mixing on drinking water quality, we measured the organic matter (OM) composition, disinfection byproduct (DBP) and metal concentrations in differently mixed ratios of GW and SW within the WDS. Fluorescence analysis revealed that the GW and SW had similar OM composition, with an almost equal ratio of humic- and protein-like OM throughout the WDS despite fluorescence indices revealing slightly different OM sources between the two water types. The tyrosine-like OM component was more variable, increasing during warmer months and towards the end of the WDS, most likely due to enhanced biofilm formation. Arsenic concentrations decreased to below 10 μg/L in the second half of the sampling campaign. Acceptable water quality was achieved after a period of destabilization and solubilization of loose deposits within the WDS resulting in their mobilization caused by water quality changes. Principal component and classification analysis, regression models and Spearman correlation coefficients revealed an association between As, OM and DBP concentrations with these correlations suggestive of their role in As mobilization in the WDS. Changing source waters, with different OM content and characteristics, corresponded to variable As release within the WDS.
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Affiliation(s)
- L Kurajica
- Croatian Institute of Public Health, Rockefeller Street 7, 10000, Zagreb, Croatia
| | - M Ujević Bošnjak
- Croatian Institute of Public Health, Rockefeller Street 7, 10000, Zagreb, Croatia.
| | - A S Kinsela
- Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW, 2052, Australia
| | - M Bieroza
- Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala, 75007, Sweden
| | - J Štiglić
- Croatian Institute of Public Health, Rockefeller Street 7, 10000, Zagreb, Croatia
| | - T D Waite
- Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW, 2052, Australia
| | - K Capak
- Croatian Institute of Public Health, Rockefeller Street 7, 10000, Zagreb, Croatia
| | - Ž Romić
- Osijek Water Supply Company, Poljski Put 1, Osijek, Croatia
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24
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Zhang S, Tian Y, Guo H, Liu R, He N, Li Z, Zhao W. Study on the occurrence of typical heavy metals in drinking water and corrosion scales in a large community in northern China. CHEMOSPHERE 2022; 290:133145. [PMID: 34921856 DOI: 10.1016/j.chemosphere.2021.133145] [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: 09/03/2021] [Revised: 11/09/2021] [Accepted: 11/30/2021] [Indexed: 06/14/2023]
Abstract
Excessive heavy metal content in drinking water could lead to red water and acute and chronic diseases. A field study in combination with batch experiments using pipe scales of drinking water distribution systems (DWDS) in the study area, was used to determine the content distribution and migration of As, Cd, Cr, Mn, Pb, and V in DWDS. In the field study, As, Cd, Cr, Pb, and V contents in pipe scales and drinking water were extremely low and did not exceed the Chinese drinking water standards. However, Mn concentrations at the end of the DWDS with aged and corrosive pipes were relatively high, which presented a risk of excessive release. The batch experiment showed that As in pipe scales would not be released into water under static immersion conditions; however, pipe scales would release excessive Cd, Cr, Mn, Pb, and V in the initial reaction stage, and the heavy metal contents released by tubercle scales in the initial release stage were at least twice as much as those released by loose scales. The mass percentage of four metals (excluding Cd and Pb) released from pipe scales was extremely low. The field study and batch experiment data both suggested a strong correlation between Cr and V released into the water, indicating a synergistic effect. There were differences in heavy metals released in the field research and the batch experiment. The amount of Cd, Cr, Pb, and V released were not consistent with its proportion in pipe scales. As release did not occur under static conditions, but may be promoted by the water flow in the actual network. The effect of water flow on heavy metal release in DWDS should be considered.
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Affiliation(s)
- Shengnan Zhang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300350, China; Tianjin Renai College, Tianjin, 301636, China
| | - Yimei Tian
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300350, China
| | - Hao Guo
- The Institute of Seawater Desalination and Multipurpose Utilization, MNR(Tianjin), Tianjin, 300192, China
| | - Ran Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300350, China
| | - Nan He
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300350, China
| | - Zhuang Li
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300350, China
| | - Weigao Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300350, China.
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25
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Tian Y, Yu T, Shen J, Zheng G, Li H, Zhao W. Cr release after Cr(III) and Cr(VI) enrichment from different layers of cast iron corrosion scales in drinking water distribution systems: the impact of pH, temperature, sulfate, and chloride. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:18778-18792. [PMID: 34699006 DOI: 10.1007/s11356-021-15754-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 07/28/2021] [Indexed: 06/13/2023]
Abstract
Chromium accumulated from source water and pipeline lining materials in corrosion scales could potentially be released into bulk water in drinking water distribution systems (DWDS). This study examined the influence of pH (pH 4, pH 5.5, pH 7, pH 8.5, pH 10), temperature (5 °C, 15 °C, 25 °C), sulfate (50 mg/L, 150 mg/L, 250 mg/L), and chloride (50 mg/L, 150 mg/L, 250 mg/L) on chromium accumulation and release between iron corrosion scale phase and the surrounding water phase. For the first time, the accumulation and release behaviors of chromium were assessed and compared in two distinct layers of iron corrosion scales based on the speciation distributions of heavy metals. Results showed that in the outer and inner layers of corrosion scales, chromium exhibited an almost similar trend but significant differences in quantity, with the outer layer accumulating less and releasing more. In particular, the average difference of chromium released after Cr(VI) enrichment from the outer and inner layers was 50.53 μg/L under the same conditions. Further studies conclusively showed that in Cr(VI) accumulation process, a portion of Cr(VI) would be reduced to Cr(III) by Fe(II) in iron corrosion scales. The mechanisms of chromium retention based on different iron (oxyhydr)oxides were discussed.
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Affiliation(s)
- Yimei Tian
- Department of Environmental Engineering, School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Tiantian Yu
- Department of Environmental Engineering, School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Jingyi Shen
- Department of Environmental Engineering, School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Guolei Zheng
- Department of Environmental Engineering, School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Han Li
- Department of Environmental Engineering, School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Weigao Zhao
- Department of Environmental Engineering, School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China.
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26
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Yao W, Gallagher DL, Dietrich AM. Risks to children from inhalation of aerosolized aqueous manganese emitted from ultrasonic humidifiers can be greater than for corresponding ingestion. WATER RESEARCH 2021; 207:117760. [PMID: 34800908 DOI: 10.1016/j.watres.2021.117760] [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: 07/06/2021] [Revised: 09/22/2021] [Accepted: 10/10/2021] [Indexed: 06/13/2023]
Abstract
UNLABELLED The essential trace element manganese (Mn) can cause neurotoxicity with inhalation acknowledged as a more severe health and cognition threat than ingestion. METHODS Over a range of aqueous Mn concentrations present in tap water, this research characterizes exposures and risks for adults and 0.25, 1, 2.5, and 6 yr old children who ingest the water and inhale respirable particles produced by a room-sized ultrasonic humidifier filled with the same water. Aqueous Mn concentrations evaluated included 50 µg/L USEPA esthetic guideline, 80 µg/L WHO infant guideline, and 120 µg/L Canadian regulatory level. Airborne-particle-bound Mn concentrations were generated for water filling an ultrasonic humidifier under four realistic room conditions (33 m3 small or 72 m3 large) with varying ventilation rates from 0.2/h -1.5/h. Average daily doses (ADD) and reference intake doses were calculated for ingestion and 8-h inhalation of humidified air. Hazard quotients (HQ) compared the intake doses and reference doses. Multi-path particle dosimetry (MPPD) model quantified the particle deposition and deposited dose in children's and adults' respiratory tracts. RESULTS At only 11 µg/L Mn, the resulting humidified air Mn exceeds USEPA's reference concentration of 0.05 µg/m3 Mn in small room with low, energy-efficient ventilation. Inhalation ADD are 2 magnitudes lower than ingestion ADD for identical water Mn concentrations and daily exposure frequency. Even so, ingestion HQs are approximately 0.2 but inhalation risk is significant (HQ>1) for children and adults when breathing Mn-humidified air under most small room conditions at 50, 80 or 120 µg/L Mn. MPPD model indicates inhaled Mn deposits in head and pulmonary regions, with greater Mn dose deposits in children than adults. CONCLUSION Inhalation of Mn-particles produced from ultrasonic humidifiers can pose greater risks than ingestion at the same water concentration, especially for children. Aqueous Mn concentration and room size influence risks. Limiting manganese exposures and setting regulations requires consideration of both ingestion and inhalation of water.
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Affiliation(s)
- Wenchuo Yao
- Department of Civil and Environmental Engineering, Virginia Tech, 413 Durham Hall, Blacksburg, Virginia 24061, United States
| | - Daniel L Gallagher
- Department of Civil and Environmental Engineering, Virginia Tech, 413 Durham Hall, Blacksburg, Virginia 24061, United States
| | - Andrea M Dietrich
- Department of Civil and Environmental Engineering, Virginia Tech, 413 Durham Hall, Blacksburg, Virginia 24061, United States.
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27
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Yu Y, Li G, Chen R, Shi B. Trihalomethanes formation enhanced by manganese chlorination and deposition in plastic drinking water pipes. WATER RESEARCH 2021; 204:117582. [PMID: 34474250 DOI: 10.1016/j.watres.2021.117582] [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: 06/07/2021] [Revised: 08/04/2021] [Accepted: 08/18/2021] [Indexed: 06/13/2023]
Abstract
Residual manganese(II) in finished water undergoes further oxidation and deposition in drinking water distribution systems (DWDS), and Mn deposits can function as sites for accumulating organic and inorganic pollutants. This study aims to explore how Mn transformation and deposition affect the formation of disinfection byproducts (DBPs) in chlorinated DWDS, and trihalomethanes (THMs) was selected as a representative DBP. In a 100 μg/L Mn system, regulated THMs (chlorinated/bromated-THMs) increased by over 20% higher than Mn-free system after 150-day operation; when 50 μg/L iodide (I-) entered pipe systems after 150 days, iodinated THMs (I-THMs) in 100 μg/L Mn system increased by over 30% compared with Mn-free system. These promotions were attributed primarily to the accumulation of biomolecules and organic substances by tight and hard chlorinated Mn deposits. The residence of inactivated cells and the bridging role of surface Mn(III) in Mn deposits increased the quantity of THM precursors in DWDS. Furthermore, the rapid catalytic oxidation of Mn(II) by preformed Mn oxides (MnOx) inhibited the conversion of free iodine (HOI/OI-) to iodate, resulting in the generation of more I-THMs. This study provides new insights into the DBP risks caused by Mn in DWDS.
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Affiliation(s)
- Ying Yu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guiwei Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ruya Chen
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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28
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Wang P, Wang H, Zhang Y, Yi J, Chen M, Jiang H, Yan J, Liu H, Ma J. Accelerated catalytic oxidation of dissolved manganese(II) by chlorine in the presence of in situ-growing 3D manganese(III)/(IV) oxide nanosheet assembly in zeolite filter. WATER RESEARCH 2021; 201:117223. [PMID: 34146760 DOI: 10.1016/j.watres.2021.117223] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 04/02/2021] [Accepted: 05/03/2021] [Indexed: 06/12/2023]
Abstract
Manganese contamination is ubiquitous in ground water. Water eutrophication also exaggerates manganese release and contamination in surface water. However, conventional manganese(II) removal process through sand filter is low-efficiency and long-term ripening. Manganese exceeding standard is still a bottleneck issue for drinking water plants. To provide a quick-setup and low-cost means, we invented an accelerated catalytic oxidation filtration process through porous zeolite filter with dynamically coating of manganese oxide nanocatalysts. In dynamic filtration process, the addition of chlorine less than redox stoichiometric consumption can efficiently remove dissolved manganese(II) from contaminated tap water, ground water and Songhua river water. Characterization results showed that a continuous manganese(III)/(IV) oxide nanosheet catalyst was dynamically in situ-growing and assembled into 3D porous superstructure in the reactive Zeolite@MnOx(s) filter. Active Mn(III) species on the edges of MnOx(s) nanosheets were dynamically generated and transferred into stable Mn(IV) species on the layer-structured surface. The cycling transformation of manganese(III)/(IV) species was responsible for the accelerated catalytic oxidation of dissolved manganese(II) by chlorine. Without process changes in drinking water plant, the porous Zeolite@MnOx(s) media could be feasibly integrated onto the existing sand filtration tanks for emergence handling of manganese(II) contamination. This novel reactive Zeolite@MnOx(s) filter with higher hydraulic conductivity provides a high-efficiency, scalable and low-cost technique for the manganese(II) removal from various of water environments.
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Affiliation(s)
- Panpan Wang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Han Wang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Yunfei Zhang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Junda Yi
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Mansheng Chen
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Haicheng Jiang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jiaying Yan
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Huiling Liu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
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29
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Anthropogenic Organic Pollutants in Groundwater Increase Releases of Fe and Mn from Aquifer Sediments: Impacts of Pollution Degree, Mineral Content, and pH. WATER 2021. [DOI: 10.3390/w13141920] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In many aquifers around the world, there exists the issue of abnormal concentrations of Fe and Mn in groundwater. Although it has been recognized that the main source of this issue is the release of Fe and Mn from aquifer sediments into groundwater under natural environmental conditions, there lacks enough reliable scientific evidence to illustrate whether the pollutants imported from anthropogenic activities, such as organics, can increase this natural release. On the basis of time series analysis and comparative analysis, the existence of an increasing effect was verified through laboratorial leaching test, and the impacts of aquatic chemical environment conditions, such as pH, on the effect were also identified. The results showed that the increase of organics in groundwater made the release of Fe and Mn more thorough, which was favorable for the increase of groundwater concentrations of Fe and Mn. The higher the contents of Fe- and Mn-bearing minerals in aquifer sediments, the higher the concentrations of Fe and Mn in groundwater after the release reaches kinetic equilibrium. Lower pH can make the leaching more thorough, but the neutral environment also increases the amount of Mn. It can be deduced that the pollutants such as organics imported by anthropogenic activities can indeed increase the releases of Fe and Mn from aquifer sediments into groundwater, thus worsening the issue of groundwater Fe and Mn pollution. The findings provide a deeper insight into the geochemical effects of Fe and Mn in the natural environment, especially in the groundwater system.
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Pre-depositing PAC-birnessite cake layer on gravity driven ceramic membrane (GDCM) reactor for manganese removal: The significance of stable flux and biofilm. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.118623] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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He Y, Pan L, Chen R, Shi B. Field studies of aluminum release and deposition in drinking water distribution systems. CHEMOSPHERE 2021; 275:130067. [PMID: 33652280 DOI: 10.1016/j.chemosphere.2021.130067] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 02/18/2021] [Accepted: 02/20/2021] [Indexed: 06/12/2023]
Abstract
Aluminum (Al) release and deposition in drinking water distribution systems (DWDS) are highly detrimental to tap water quality. In this study, five drinking water treatment plant supply areas in two cities of China were examined to understand the transportation stability of Al in the DWDS. The two cities were selected based on the wide disparity reported in pH and turbidity in the finished and tap water qualities, with higher fluctuation of pH (average 8.0) and turbidity (average 0.78 NTU) reported in the northern and southern cities, respectively. Results showed that hydraulic conditions such as hydraulic shock or increased flow velocity had a more significant effect on the release and deposition of particulate Al, which could be reflected by turbidity when it was greater than 0.3 NTU, since turbidity and particulate Al were significantly positively correlated. Particulate Al concentration varied by more than 140 μg/L when turbidity fluctuated within 0.45-1.67 NTU. However, when turbidity was below 0.3 NTU, the particulate Al transported stably at low concentration. pH fluctuations contributed to the change of soluble Al concentration. Even above 50 μg/L soluble Al in the finished water could transport stably in the DWDS when pH fluctuated slightly in 6.6-7.0. However, when the pH fluctuated in 7.8-8.4, the soluble Al concentration varied by more than 100 μg/L. This study provides reference indicators of turbidity and pH for identifying the risk of Al in the DWDS.
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Affiliation(s)
- Yitian He
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Linlin Pan
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ruya Chen
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
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Chen R, Li G, He Y, Pan L, Yu Y, Shi B. Field study on the transportation characteristics of PFASs from water source to tap water. WATER RESEARCH 2021; 198:117162. [PMID: 33962237 DOI: 10.1016/j.watres.2021.117162] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 03/15/2021] [Accepted: 04/13/2021] [Indexed: 06/12/2023]
Abstract
Perfluoroalkyl substances (PFASs) can occur in water sources, pass through drinking water treatment plants (DWTPs), drinking water distribution systems (DWDSs), to the consumer taps. This investigation was carried out to present the transportation behaviors of 17 PFASs, involving seven DWTPs with different water sources, raw water transportation modes, treatment processes, and DWDS structures in eastern and northern China. The results showed that the long-distance raw water transportation pipelines removed a certain extent of PFASs from raw water, probably due to the accumulation of loose deposits. The long-distance, open-channel South-to-North water diversion increased PFAS contamination risk. In the DWTPs, granular activated carbon (GAC) adsorption and ultraviolet radiation removed less than 25% of PFASs, but ozonation-biological activated carbon (O3-BAC) was superior to GAC alone in removing PFASs. Loose deposits couldsignificantly influence PFAS accumulation and release within branch-structured DWDSs. In loop-structured DWDSs, finished water with different PFAS characteristics could mix along the pipeline, with the corresponding DWTP as the center, ultimately forming a relatively uniform distribution in the entire DWDS.
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Affiliation(s)
- Ruya Chen
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guiwei Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yitian He
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Linlin Pan
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ying Yu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Kurajica L, Ujević Bošnjak M, Kinsela AS, Štiglić J, Waite TD, Capak K, Pavlić Z. Effects of changing supply water quality on drinking water distribution networks: Changes in NOM optical properties, disinfection byproduct formation, and Mn deposition and release. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 762:144159. [PMID: 33360458 DOI: 10.1016/j.scitotenv.2020.144159] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/26/2020] [Accepted: 11/26/2020] [Indexed: 06/12/2023]
Abstract
Field studies were conducted in a Croatian city supplied by two distinct groundwater sources (referred to as A and B) to investigate both the effects of changing water source on the water quality in the drinking water supply system, as well as to further understand discoloration events that occurred in city locations that switched water from source A to B. The water treatment processes at site A were found to alter organic matter (OM) characteristics, removing humic substances while enhancing protein-derived (tryptophan) content. Although the humic-like component predominated in raw waters, microbially/protein-derived components were found to increase throughout the distribution networks of both systems. Disinfection byproducts (DBPs) such as total trihalomethane (TTHM) and total haloacetic acid (THAA) were prevalent in water distribution system (WDS)-A, which correlated with elevated OM content as well as re-chlorination with hypochlorite (NaOCl). Our field study revealed that THMs were more readily formed than HAAs during ClO2 treatment. Unsurprisingly, chlorite concentrations were generally higher than chlorate concentrations during ClO2 treatment, whereas (secondary) NaOCl disinfection contributed to higher chlorate production. Principal component analysis indicated that variable pH values and humic-like OM could affect Mn, As and Al concentrations at the consumer's tap. Our results suggested that although Mn concentrations complied with regulations at WDS-B and were below 50 μg/L after disinfection, Mn was oxidized and formed particulate Mn oxides capable of causing discoloration events depending on prevailing network physico-chemical and hydraulic conditions. Aluminium also appears to be released during hydraulic disturbances from extensive deposits within the network. Thermodynamic calculations showed that Mn-oxidation was strongly dependent upon the ORP, and to lesser extent the pH value. Collectively, our results confirm that ensuring the provision of safe drinking waters to consumers requires an understanding of water quality across entire distribution networks in addition to any routine post-treatment monitoring.
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Affiliation(s)
- L Kurajica
- Croatian Institute of Public Health, Rockefeller street 7, 10000 Zagreb, Croatia
| | - M Ujević Bošnjak
- Croatian Institute of Public Health, Rockefeller street 7, 10000 Zagreb, Croatia.
| | - A S Kinsela
- Water Research Centre, University of New South Wales, Sydney, NSW 2052, Australia
| | - J Štiglić
- Croatian Institute of Public Health, Rockefeller street 7, 10000 Zagreb, Croatia
| | - T D Waite
- Water Research Centre, University of New South Wales, Sydney, NSW 2052, Australia
| | - K Capak
- Croatian Institute of Public Health, Rockefeller street 7, 10000 Zagreb, Croatia
| | - Z Pavlić
- Slavonski Brod Water Supply Company, Nikole Zrinskog 25, 35000 Slavonski Brod, Croatia
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Tian Y, Li J, Jia S, Zhao W. Co-release potential and human health risk of heavy metals from galvanized steel pipe scales under stagnation conditions of drinking water. CHEMOSPHERE 2021; 267:129270. [PMID: 33338723 DOI: 10.1016/j.chemosphere.2020.129270] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 12/02/2020] [Accepted: 12/07/2020] [Indexed: 06/12/2023]
Abstract
The re-release of heavy metals accumulated in the drinking water distribution systems (DWDSs) may pose a significant threat to water quality and human health. In this work, the pipe scales in the actual DWDS were collected, and their physicochemical characteristics were investigated by SEM, XRF, XRD, XPS, and sequential extraction procedure. The co-release potential of heavy metals under different scale dosages, temperatures, and stagnation times was explored by stagnation release tests. Pearson correlation analysis on metal release and human health risk assessment was used to reveal the inter-metal correlation and potential risk of metal release. The results showed that the metal release potential under stagnation water conditions arose primarily from the acid-soluble fraction. The chronic non-carcinogenic risk of soluble metals followed the order: Mn > Fe > Zn > Pb. The risk caused by the soluble metal release could be ignored (HI < 1, HI: hazard index) under normal stagnation times (within 8 h). The major finding of this work was that Ca and Mn were more labile to release and had a significant linear co-release correlation (scale powder: R2 = 0.906, p < 0.01; pipe section: R2 = 0.982, p < 0.01), which indicated their co-existence and linear co-release. Ca was recognized as the "major metal" that affected the release of trace metals. The health risk probably increased with the release of Ca, which could also be used as an "indicator" of Mn release.
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Affiliation(s)
- Yimei Tian
- Department of Environmental Engineering, School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Jiaxin Li
- Department of Environmental Engineering, School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Shichao Jia
- Department of Environmental Engineering, School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Weigao Zhao
- Department of Environmental Engineering, School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China.
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Chen R, Zhuang Y, Yu Y, Shi B. Enhanced perfluorooctanoic acid (PFOA) accumulation by combination with in-situ formed Mn oxides under drinking water conditions. WATER RESEARCH 2021; 190:116660. [PMID: 33279743 DOI: 10.1016/j.watres.2020.116660] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 11/18/2020] [Accepted: 11/19/2020] [Indexed: 06/12/2023]
Abstract
Particulate manganese oxide (MnOx) deposition in drinking water distribution systems (DWDS) gives rise to the risk of water discoloration at the consumers' tap; however, its role in the fate and transport of trace organic pollutants in DWDS is not clear. Perfluorooctanoic acid (PFOA), a persistent organic pollutant frequently detected in natural water, was selected to investigate the potential effect of MnOx on its transportation behavior under DWDS conditions through laboratory batch experiments. The results show that PFOA can be greatly combined with MnOx formed in-situ through a Mn(II) oxidation process by free chlorine. However, the accumulation of PFOA by preformed MnOx was negligible. It was found that 1 mg/L Mn captured over 50% of PFOA with an initial concentration of 50 ng/L during oxidation. The water compositions of actual water could contribute to the effect of PFOA accumulation to a certain extent. Characterization of the solid products revealed that PFOA is homogenously embedded into MnOx. The combination of PFOA with MnOx occurs through a bridging effect of Mn(II) between the surface hydroxyls of MnOx and the -COOH group of PFOA. The resulting MnOx-PFOA particles were more inclined to agglomerate, enabling possibly easy deposition onto the pipe wall than ordinary MnOx particles. This study provides insights into the co-occurrence of metal deposits with PFOA and the potential risks posed by PFOA accumulation to consumers through the water distribution process.
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Affiliation(s)
- Ruya Chen
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuan Zhuang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Ying Yu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Pei Y, McLeod JF, Payne SJ, She Z. A Comparative Study of Electroanalytical Methods for Detecting Manganese in Drinking Water Distribution Systems. Electrocatalysis (N Y) 2021. [DOI: 10.1007/s12678-020-00639-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Zhang S, Tian Y, Guo Y, Shan J, Liu R. Manganese release from corrosion products of cast iron pipes in drinking water distribution systems: Effect of water temperature, pH, alkalinity, SO 42- concentration and disinfectants. CHEMOSPHERE 2021; 262:127904. [PMID: 32799153 DOI: 10.1016/j.chemosphere.2020.127904] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 07/31/2020] [Accepted: 08/01/2020] [Indexed: 06/11/2023]
Abstract
Manganese accumulated in corrosion scales on drinking water distribution systems (DWDSs) can be released into bulk water, causing discolouration and thereby leading to customer concerns about drinking water quality. A static release experiment was conducted on iron pipe scales under three different temperatures, pH values, alkalinity values, sulfate (SO42-) concentrations, and disinfectants to study the separate effect of these factors on Mn release from pipe scales under stagnant conditions. Results showed that more Mn was released from corrosion scales under the conditions of lower pH, lower alkalinity, higher temperature, and higher SO42- concentrations. Three commonly used disinfectants, sodium hypochlorite (NaClO), chlorine dioxide (ClO2), and monochloramine (NH2Cl) were found to inhibit the release of Mn from iron corrosion scales, with the ranked order of inhibitory effect of ClO2≈NaClO > NH2Cl under the same CT (product of disinfectant concentration and contact time) value. The orthogonal experimental results indicated that SO42- and alkalinity had extremely significant effects on the release of Mn from pipe scales, while pH and disinfectant type had a significant impact on the release of Mn from pipe scales. Thus, the SO42- concentration and alkalinity of the bulk water should be determined to avoid excessive release of Mn into drinking water. However, further investigation of the effect of disinfectants on Mn release in DWDSs is necessary. This research helps establish a systematic understanding of the influential factors in Mn release from pipe scales into bulk water, as well as their significant relationships.
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Affiliation(s)
- Shengnan Zhang
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin, 300350, China; Renai College, Tianjin University, Jinghai District, Tianjin, 301636, China
| | - Yimei Tian
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin, 300350, China.
| | - Yajing Guo
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin, 300350, China; Beifang Investigation, Design & Research Co. LTD, Hexi District, Tianjin, 300222, China
| | - Jinlin Shan
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin, 300350, China
| | - Ran Liu
- School of Environmental Science and Engineering, Tianjin University, 135 Yaguan Road, Jinnan District, Tianjin, 300350, China
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Shu J, Wu Y, Ji Y, Chen M, Wu H, Gao Y, Wei L, Zhao L, Huo T, Liu R. A new electrochemical method for simultaneous removal of Mn 2+and NH 4+-N in wastewater with Cu plate as cathode. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 206:111341. [PMID: 32979720 DOI: 10.1016/j.ecoenv.2020.111341] [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: 04/06/2020] [Revised: 09/08/2020] [Accepted: 09/10/2020] [Indexed: 06/11/2023]
Abstract
In this study, a new electrochemical method was used to simultaneously efficient removal of Mn2+ and NH4+-N in wastewater with Cu plate as cathode. The effects of various reaction parameters on the concentrations of Mn2+, NH4+-N and by-products (NO3--N and NO2--N, free chlorine and residual chlorine), as well as the removal mechanism were investigated. The results showed that the removal efficiencies of Mn2+ and NH4+-N were 99.1% and 92.9%, and the concentrations of NO3--N, NO2--N, free chlorine and residue chlorine were 0.73 mg/L, 0.15 mg/L, 0.13 mg/L and 0.63 mg/L reacting for 3 h at room temperature, respectively, when the current density was 10 mA/cm2, the mass ratio of ClO- and Cl- was 1:1, the initial pH was 9. The concentrations of Mn2+, NH4+-N and by-products in wastewater met the integrated wastewater discharge standard (GB8978-1996). In addition, spherical manganese oxide was deposited on the anode plate, and spherical manganese oxide collapsed over electrolysis time. Manganese was mainly removed in the form of MnO, Mn(OH)2 and MnO2. NH4+-N was mainly oxidized to N2. Economic evalution revealed that the treatment cost was 2.93 $/m3.
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Affiliation(s)
- Jiancheng Shu
- Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang, 621010, China.
| | - Yuhao Wu
- Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang, 621010, China
| | - Yun Ji
- Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang, 621010, China
| | - Mengjun Chen
- Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang, 621010, China
| | - Haiping Wu
- Sichuan Jiuzhou Technician College, Jiusheng Road, Mianyang, 621099, China
| | - Yushi Gao
- Guizhou Institute of Building Materials Scientific Research and Design Limited Company, Guiyang, 550007, China
| | - Liang Wei
- Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang, 621010, China
| | - Li Zhao
- Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang, 621010, China
| | - Tingting Huo
- Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang, 621010, China
| | - Renlong Liu
- School of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400044, China
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Tian C, Feng C, Chen L, Wang Q. Impact of water source mixture and population changes on the Al residue in megalopolitan drinking water. WATER RESEARCH 2020; 186:116335. [PMID: 32882454 DOI: 10.1016/j.watres.2020.116335] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 08/19/2020] [Accepted: 08/22/2020] [Indexed: 06/11/2023]
Abstract
This study establishes a new understanding of the contributions of Al residue in a megalopolitan drinking water supply system with mixed water sources. The different influences and contributions of foreign water source, resident migration and season changing to Al residue in drinking water were investigated. Especially, the role of Southern water transferred over 1200 km via the South-to-North Water Diversion Project in the Al residue of drinking water supply system of a northern megalopolitan were revealed for the first time. Comparisons of big data on Al residue in the water supply system with sole and mixed water sources showed that the introduction of Southern water enhanced the Al residue in drinking water by over 35%. The world's largest annual residents' migration during Chinese Lunar New Year and the changes of season affect the water pipework hydrodynamics, which were embodied as the periodic changes of particulate aluminium and the relations with resident's temporal-spatial distribution in the megalopolitan. Because of the differences in water quality, Southern water promotes the release of historically deposited Al and facilitates the cleaning of old pipes.
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Affiliation(s)
- Chenhao Tian
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, P R China
| | - Chenghong Feng
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, P R China.
| | - Lei Chen
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875, P R China
| | - Qixuan Wang
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875, P R China
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Zhou X, Kosaka K, Nakanishi T, Welfringer T, Itoh S. Manganese accumulation on pipe surface in chlorinated drinking water distribution system: Contributions of physical and chemical pathways. WATER RESEARCH 2020; 184:116201. [PMID: 32726736 DOI: 10.1016/j.watres.2020.116201] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 07/15/2020] [Accepted: 07/17/2020] [Indexed: 06/11/2023]
Abstract
The accumulation of manganese in drinking water distribution systems often causes problems of "black water" in customers' taps. In this study, Mn accumulation onto a pipe surface under chlorinated conditions was investigated by focusing on the different states of Mn in the water. Lab-scale experiments suggested that the accumulation process included both the attachment of particulate Mn onto the surface (i.e., physical pathway) and the autocatalytic oxidation of Mn ions on the surface (i.e., chemical pathway). Based on the experimental results, a numerical model of Mn accumulation on the pipe surface via the two pathways was established. According to the model predictions, the physical pathway contributed less than the chemical pathway over time since the latter accelerated as Mn accumulation increased. The chemical pathway contributed 94% when the concentration of total Mn was 10 µg/L throughout the experiment, but only 67% when the concentration was 100 µg/L. Thus, the chemical pathway was more important for low concentrations of total Mn. In addition, the type of pipe materials used only influenced the physical pathway, while the presence of bromide directly enhanced the chemical pathway. In conclusion, limiting the chemical pathway was suggested as an effective strategy for reducing Mn accumulation during long-term operation, which is achieved by controlling the state of Mn in finished water.
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Affiliation(s)
- Xinyi Zhou
- Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto University Katsura, Nishikyo, Kyoto 615-8540, Japan
| | - Koji Kosaka
- Department of Environmental Health, National Institute of Public Health, 2-3-6 Minami, Wako, Saitama 351-0197, Japan
| | - Tomohiro Nakanishi
- Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto University Katsura, Nishikyo, Kyoto 615-8540, Japan.
| | - Théo Welfringer
- Graduate School of Environmental Engineering and Water Resource Management, National School for Water and Environmental Engineering, 1 quai Koch, 67000 Strasbourg, France
| | - Sadahiko Itoh
- Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto University Katsura, Nishikyo, Kyoto 615-8540, Japan
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Decision-Making Tools to Manage the Microbiology of Drinking Water Distribution Systems. WATER 2020. [DOI: 10.3390/w12051247] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
This paper uses a two-fold multi-criteria decision-making (MCDM) approach applied for the first time to the field of microbial management of drinking water distribution systems (DWDS). Specifically, the decision-making trial and evaluation laboratory (DEMATEL) was applied removing the need for reliance on expert judgement, and analysed interdependencies among water quality parameters and microbiological characteristics of DWDS composed of different pipe materials. In addition, the fuzzy technique for order preference by similarity to ideal solution (FTOPSIS) ranked the most common bacteria identified during trials in a DWDS according to their relative abundance while managing vagueness affecting the measurements. The novel integrated approach presented and proven here for an initial real world data set provides new insights in the interdependence of environmental conditions and microbial populations. Specifically, the application shows as the bacteria having associated the most significant microbial impact may not be the most abundant. This offers the potential for integrated management strategies to promote favourable microbial conditions to help safeguard drinking water quality.
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Li G, Pan W, Zhang L, Wang Z, Shi B, Giammar DE. Effect of Cu(II) on Mn(II) Oxidation by Free Chlorine To Form Mn Oxides at Drinking Water Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:1963-1972. [PMID: 31935075 DOI: 10.1021/acs.est.9b06497] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The chemical oxidation of dissolved Mn(II) to Mn(III/IV) oxides (MnOx) can lead to the accumulation of Mn deposits in drinking water distribution systems. However, Mn(II) oxidation by free chlorine is quite slow under mild conditions (e.g., pH 7.7 and 1.0 mg/L Cl2). This study found a significant role for Cu(II) in Mn(II) oxidation under conditions relevant to the supply of chlorinated drinking water. At pH 7.7, dissolved Cu(II) accelerated Mn(II) oxidation more than 10 times with a dose of 20 μg/L. Solid characterization revealed that during Mn(II) oxidation, Cu(II) adsorbed to freshly formed MnOx and produced Mn-Cu mixtures (denoted as MnOx-Cu(II)). An autocatalytic model for the reaction kinetics suggested that the freshly formed MnOx-Cu(II) had a much higher catalytic activity than that of pure MnOx. Solid CuO also catalyzed Mn(II) oxidation, and kinetic modeling indicated that after an initial oxidation of Mn(II) facilitated by the CuO surface, the freshly formed MnOx-Cu(II) on CuO surface played the dominant role in accelerating further Mn(II) oxidation. This study indicates a high potential for the formation of Mn oxides at locations in a drinking water distribution system or in premise plumbing where both Mn(II) and Cu(II) are available. It provides insights into the co-occurrence of other metals with Mn deposits that is frequently observed in distribution systems.
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Affiliation(s)
- Guiwei Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences , Chinese Academy of Sciences , Beijing 100085 , China
- Department of Energy, Environmental and Chemical Engineering , Washington University in St. Louis , St. Louis , Missouri 63130 , United States
- University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Weiyi Pan
- Department of Energy, Environmental and Chemical Engineering , Washington University in St. Louis , St. Louis , Missouri 63130 , United States
| | - Lili Zhang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences , Chinese Academy of Sciences , Beijing 100085 , China
| | - Ziqiao Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences , Chinese Academy of Sciences , Beijing 100085 , China
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences , Chinese Academy of Sciences , Beijing 100085 , China
- University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Daniel E Giammar
- Department of Energy, Environmental and Chemical Engineering , Washington University in St. Louis , St. Louis , Missouri 63130 , United States
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