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Zhao S, Zhang J, Yang W, Liu M, Yan Y, Jia W. Application of laminarin as a novel coagulant aid to improve coagulation-ultrafiltration efficiency. ENVIRONMENTAL RESEARCH 2023; 228:115909. [PMID: 37060989 DOI: 10.1016/j.envres.2023.115909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 04/10/2023] [Accepted: 04/12/2023] [Indexed: 05/16/2023]
Abstract
Polyacrylamide (PAM) is the most commonly used coagulant aid in coagulation-ultrafiltration (C-UF) systems; however, its hydrolyzed monomer is harmful to the human nervous system. In this study, laminarin (LA), was extracted from Laminaria japonica and used as a novel coagulant aid to improve coagulation efficiency and reduce membrane fouling during the C-UF process. Optimal LA usage conditions were systematically examined and compared with those of PAM to evaluate their potential for industrial applications. The results revealed that coagulation efficiency could be enhanced by 15-35% with moderate LA addition, which exhibited comparable aid effects to PAM. LA exhibited the highest coagulation aid effect at pH 8-9, and under this condition, turbidity and natural organic matter (NOM) removal achieved 82% and 54%, respectively. Compared with a one-time LA dosing strategy, the pollutant removal capacity of batch dosing was superior. Even in lower water temperatures (5-15 °C), coagulation efficiency was still satisfied, which exhibited a good practical application perspective. The coagulation aid role of LA should be attributed to its long-chain molecular structure, which enhances the bridging role between micro flocs and assists floc growth, thus facilitating the formation of large flocs. In addition, LA adsorption on floc surface was conducive to the direct electrostatic repulsion effect of electronegative membrane, which resulted in a more porous cake layer and higher membrane flux. Therefore, LA exhibits excellent application potential for eliminating NOM while simultaneously reducing membrane fouling through the C-UF process.
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Affiliation(s)
- Shuang Zhao
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou, 221000, China.
| | - Jianguo Zhang
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou, 221000, China.
| | - Weihua Yang
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou, 221000, China.
| | - Mingkai Liu
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou, 221000, China.
| | - Yan Yan
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou, 221000, China.
| | - Wenlin Jia
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou, 221000, China.
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Su Z, Liu T, Men Y, Li S, Graham N, Yu W. Understanding point-of-use tap water quality: From instrument measurement to intelligent analysis using sample filtration. WATER RESEARCH 2022; 225:119205. [PMID: 36215843 DOI: 10.1016/j.watres.2022.119205] [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] [Received: 06/13/2022] [Revised: 09/19/2022] [Accepted: 10/03/2022] [Indexed: 06/16/2023]
Abstract
In most cases, point-of-use tap water quality is not routinely monitored due to widely-dispersed sampling sites and the costly tests. Although previous studies have revealed the variation of drinking water quality during distribution in municipal networks, the influence of aging pipes in buildings on quality is still unknown and this makes it difficult for water utilities to conduct regular maintenance. Herein, we have undertaken a survey of tap water samples across 8 districts in Beijing (China) to evaluate the potential effects of pipe age on point-of-use water quality, including turbidity, organic matter characteristics, and bacterial community. By grouping the collected samples according to the pipe age and source water respectively, the results suggested that bacterial diversity is significantly influenced by the pipe age. However, bacterial community structure is clearly influenced by the source water. Similarly, aging pipes in buildings are also responsible for the deterioration of the final water quality, and their effects have been closely linked to selected water quality parameters by evaluating the relevant factors. Moreover, the interrelationships between physico-chemical parameters and bacteria abundance were identified. For example, pH, Ca2+, Mg2+, Na+ and K+ showed a positive relationship with Bacillus abundance. In addition, an intelligent analysis method for understanding pipe age, organic matter concentration, and hardness (i.e., Ca2+ and Mg2+ concentration), based on image analysis of filtered membranes has been developed. The accuracy of prediction was encouraging, but can be improved with the collection of more data from tap water samples. We expect that this method can be exploited by the public to monitor their tap water and provide a feasible and cost-effective approach for water suppliers to locate aging/deteriorating pipes which need to be replaced or maintained.
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Affiliation(s)
- Zhaoyang Su
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Ting Liu
- School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Yujie Men
- Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521, United States
| | - Shuo Li
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Nigel Graham
- Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Wenzheng Yu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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Du P, Li X, Yang Y, Fan X, Fang X, Zhou Z. Enhanced coagulation by two-stage alum addition: the role of solution pH, floc breakage and assistant of non-ionic polyacrylamide. ENVIRONMENTAL TECHNOLOGY 2021; 42:4456-4465. [PMID: 32345190 DOI: 10.1080/09593330.2020.1762757] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 04/25/2020] [Indexed: 06/11/2023]
Abstract
Coagulation process is highly influenced by solution pH, floc breakage, and coagulant aid. In this work, two-stage addition of alum-based coagulants, polyaluminum chloride (PACl) and aluminum sulfate (Al2(SO4)3), was compared to their one-stage addition with the same total dosage. The dose ratio of primary and secondary addition was optimised. The effects of solution pH, floc breakage and dosing timing of coagulant aid of non-ionic polyacrylamide (NPAM) on coagulation efficiency and floc property were investigated. The results showed that two-stage addition of PACl showed less sensitivity with the variation of pH. Compared to PACl, two-stage addition of Al2(SO4)3 was more sensitive to the solution pH, especially when the pH ranged from 7 to 10. For all cases, the presence of floc breakage improved the removal of colloidal particles. The coagulation mechanism of primary coagulant was charge neutralisation, while other mechanism was involved with the secondary addition of coagulant. Compared to one-stage addition, the settling performance of aggregates and particulates removal in two-stage addition was more effective with the variation of dosage or dosing timing of NPAM. The present work provides detailed operating parameters for this coagulation strategy.
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Affiliation(s)
- Peng Du
- College of Architecture and Civil engineering, Beijing University of Technology, Beijing, People's Republic of China
| | - Xing Li
- College of Architecture and Civil engineering, Beijing University of Technology, Beijing, People's Republic of China
| | - Yanling Yang
- College of Architecture and Civil engineering, Beijing University of Technology, Beijing, People's Republic of China
| | - Xiaoyan Fan
- College of Architecture and Civil engineering, Beijing University of Technology, Beijing, People's Republic of China
| | - Xiaobo Fang
- College of Architecture and Civil engineering, Beijing University of Technology, Beijing, People's Republic of China
| | - Zhiwei Zhou
- College of Architecture and Civil engineering, Beijing University of Technology, Beijing, People's Republic of China
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Chen Y, Feng L, Liu B, Peng J, Chen Y, Xu C, Ren J. Study of microwave‐template initiated copolymerization peculiarity and evaluation on the coal floc distinctive behavior and flocculation performance. J Appl Polym Sci 2020. [DOI: 10.1002/app.49519] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Yao Chen
- School of River and Ocean EngineeringChongqing Jiaotong University Chongqing China
| | - Li Feng
- School of Civil and Transportation EngineeringGuangdong University of Technology, Higher Education Mega Center Guangzhou Guangdong China
| | - Bingzhi Liu
- School of Civil and Transportation EngineeringGuangdong University of Technology, Higher Education Mega Center Guangzhou Guangdong China
| | - Junlin Peng
- School of Mechanical Engineering, Xiangtan University Xiangtan Hunan China
| | - Yuning Chen
- School of Civil and Transportation EngineeringGuangdong University of Technology, Higher Education Mega Center Guangzhou Guangdong China
| | - Chuang Xu
- School of Civil and Transportation EngineeringGuangdong University of Technology, Higher Education Mega Center Guangzhou Guangdong China
| | - Jie Ren
- Key Laboratory of the Three Gorges Reservoir Region's Eco‐Environment, Ministry of EducationChongqing University Chongqing China
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Su Z, Liu T, Li X, Graham NJD, Yu W. Tracking metal ion-induced organic membrane fouling in nanofiltration by adopting spectroscopic methods: Observations and predictions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 708:135051. [PMID: 31796279 DOI: 10.1016/j.scitotenv.2019.135051] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 10/16/2019] [Accepted: 10/16/2019] [Indexed: 06/10/2023]
Abstract
Natural organic matter (NOM) with the size approaching to membrane pore size is commonly considered as the crucial component leading to severe pore blocking and superfluous energy consumption. Aquatic metal ions coexisting with this NOM constituent (target NOM) exert a significant influence on membrane filtration performance; however, little work elucidated their interactions and the impacts on nanofiltration (NF). Therefore, we systematically investigated this issue by titrating three environmentally-relevant metal ions (Al3+, Fe3+ and Cu2+) into the target NOM sample obtained by pre-filtering using NF membrane. Fast spectrophotometric techniques were employed to observe the interactive performance. Results suggested that all metal ions at their critical concentrations caused severe flux decline; Cu2+ at a very low concentration of 5 μM, Al3+ and Fe3+ at 20 μM. NF performance recovered when the concentrations were beyond their critical values, and was improved at excessive concentration when flocs formed. Relationship between spectroscopic characteristics and NF performance was particularly addressed. UV-vis spectrum can be expected to be useful and predictive in membrane fouling control when Al3+ or Fe3+ presented. However, fluorescence fingerprint was not likely that effective since fluorescence intensity continuously reduced with the increasing metal ion concentration, attributed to their quenching effect on NOM fluorophores.
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Affiliation(s)
- Zhaoyang Su
- Key Laboratory of Drinking Water Science and Technology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK; College of Architecture and Civil Engineering, Beijing University of Technology, Beijing 100024, China.
| | - Ting Liu
- Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK; School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China.
| | - Xing Li
- College of Architecture and Civil Engineering, Beijing University of Technology, Beijing 100024, China.
| | - Nigel J D Graham
- Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK.
| | - Wenzheng Yu
- Key Laboratory of Drinking Water Science and Technology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK.
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Moruzzi RB, da Silva PG, Sharifi S, Campos LC, Gregory J. Strength assessment of Al-Humic and Al-Kaolin aggregates by intrusive and non-intrusive methods. Sep Purif Technol 2019. [DOI: 10.1016/j.seppur.2019.02.033] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Su Z, Li X, Yang Y, Fan Y. Probing the application of a zirconium coagulant in a coagulation–ultrafiltration process: observations on organics removal and membrane fouling. RSC Adv 2017. [DOI: 10.1039/c7ra08038g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The Zr coagulant offered improved turbidity and organics removal and was beneficial in alleviating membrane fouling, particularly the irreversible fouling.
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Affiliation(s)
- Zhaoyang Su
- College of Architecture and Civil Engineering
- Beijing University of Technology
- Beijing 100124
- P. R. China
| | - Xing Li
- College of Architecture and Civil Engineering
- Beijing University of Technology
- Beijing 100124
- P. R. China
| | - Yanling Yang
- College of Architecture and Civil Engineering
- Beijing University of Technology
- Beijing 100124
- P. R. China
| | - Yiran Fan
- Department of Civil and Environmental Engineering
- Imperial College London
- South Kensington Campus
- London SW7 2AZ
- UK
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