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Lv Z, Zhang S, Jiao W, Zuo X, Zhang Y, Liu Y. High-efficiency cleaning technology and lifespan prediction for the ceramic membrane treating secondary treated effluent. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2023; 88:321-338. [PMID: 37452550 PMCID: wst_2023_209 DOI: 10.2166/wst.2023.209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
Chemical cleaning is one of the key technical means to control membrane fouling, restore membrane flux and ensure the stable operation of membrane systems. In the experiment, the six most representative chemical cleaning agents for ceramic membranes, such as sulfuric acid (H2SO4), sodium hydroxide (NaOH), sodium hypochlorite (NaClO), ethylenediaminetetraacetic acid disodium salt (EDTA-Na2), sodium dodecyl sulfate (SDS) and nonylphenol polyoxyethylene ether (OP-10), were used as research objects. The cleaning effect of the two-step combined cleaning of chemical cleaning agents on the fouled membrane was systematically investigated. Results showed that the order of the chemical cleaning agent had a significant effect on the cleaning effect. The best chemical cleaning program was determined to be NaClO first and then SDS: the fouled ceramic membrane was soaked in NaClO solution at 0.15% for 2.5 h and further soaked in SDS solution at five times its own critical micelle concentration for 2.5 h. The predicted long-term lifespan of the ceramic membranes was 4.91 years. Scanning electron microscopy-energy spectrum analysis showed that the surface roughness of the cleaned ceramic membrane was slightly higher than that of the new membrane. The contact angle was slightly lower than that of the new membrane.
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Affiliation(s)
- Zongwei Lv
- School of Civil Engineering and Architecture, University of Jinan, Jinan 250022, China E-mail:
| | - Shoubin Zhang
- School of Civil Engineering and Architecture, University of Jinan, Jinan 250022, China
| | - Wenhai Jiao
- Jinan Municipal Engineering Design & Research Institute (Group) Co., Ltd, Jinan 250003, China
| | - Xinyi Zuo
- School of Civil Engineering and Architecture, University of Jinan, Jinan 250022, China
| | | | - Yutian Liu
- Jinan Municipal Engineering Design & Research Institute (Group) Co., Ltd, Jinan 250003, China
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2
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Boussouga YA, Okkali T, Luxbacher T, Schäfer AI. Chromium (III) and chromium (VI) removal and organic matter interaction with nanofiltration. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 885:163695. [PMID: 37100133 DOI: 10.1016/j.scitotenv.2023.163695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 04/18/2023] [Accepted: 04/19/2023] [Indexed: 05/10/2023]
Abstract
Chromium (Cr) is a toxic inorganic contaminant for drinking water, in which the concentration has to be controlled for human health and safety. Cr retention was investigated with stirred cell experiments using sulphonated polyethersulfone nanofiltration (NF) membranes of different molecular weight cut-off (MWCO). Cr(III) and Cr(VI) retention follow the order of the MWCO of the studied NF membranes; HY70-720 Da > HY50-1000 Da > HY10-3000 Da with a pH dependency, especially for Cr(III). The importance of the charge exclusion was highlighted when Cr(OH)4- (for Cr(III)) and CrO42- (for Cr(VI)) was the predominant species in the feed solution. In presence of organic matter, namely humic acid (HA), Cr(III) retention increased by 60 %, while no influence of HA was observed for Cr(VI). HA did not induce major modifications on the membrane surface charge for these membranes. Solute-solute interaction, in particular Cr(III)-HA complexation, was the responsible mechanism for the increase in Cr(III) retention. This was confirmed by asymmetric flow field-flow fractionation, coupled with inductively coupled plasma mass spectrometry (FFFF-ICP-MS) analysis. Cr(III)-HA complexation was significant at HA concentrations as low as 1 mgC/L. The chosen NF membranes were able to achieve the EU guideline (25 μg/L) for Cr in drinking water for a feed concentration of 250 μg/L.
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Affiliation(s)
- Youssef-Amine Boussouga
- Institute for Advanced Membrane Technology (IAMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
| | - Timur Okkali
- Institute for Advanced Membrane Technology (IAMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | | | - Andrea I Schäfer
- Institute for Advanced Membrane Technology (IAMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
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Mailler R, Pouillaude J, Fayolle Y, Oliveira Filho M, Causserand C, Rocher V. Long-term performances and membrane lifespan of full-scale MBR treating filtrate from sludge ultra-dewatering. ENVIRONMENTAL TECHNOLOGY 2023; 44:1653-1666. [PMID: 34817315 DOI: 10.1080/09593330.2021.2010809] [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: 07/30/2021] [Accepted: 11/13/2021] [Indexed: 06/13/2023]
Abstract
An MBR treating filtrate from sludge ultra-dewatering (FSD) was studied to evaluate the real applicability to concentrated effluents. The MBR operation is comparable to conventional wastewater MBRs in terms of F/M and nitrogen to sludge ratios, SRT and MLSS in biological tanks. On the contrary, the volume treated is lower with a comparable pollution load, the effluent being concentrated in nitrogen and carbon. Very high and stable ammonium (97.7 ± 2.4%), total phosphorus (81.8 ± 11.9%), chemical (89.5 ± 2.3%) and biochemical oxygen demands (98.8 ± 0.7%) removals are observed despite a significant modification of the FSD composition. The MBR removal performances are whether comparable or greater than those reported at full-scale for Sharon or Anammox processes. The evolution of membranes properties, in particular, the decrease of permeability induced by the irreversible fouling, leads to a decrease of the daily permeate volume produced and an increase of the chemical cleaning need. The membrane lifespan was determined to be 5.5 years based on both the permeability loss and TSS in permeate. The permeability is directly correlated to the cumulated filtered flux of colloidal matter and a total of 350 kg O2/m2 of the membrane (COD in the supernatant) is needed to reach a permeability below 100 LMH/bar. The specific energy consumption is comparable to other wastewater MBRs in kWh/kgCOD removed but the intensive chemical cleanings need to be 2.5-4.5 times more frequent. Overall, it can be concluded that MBR is adapted to treat FSD efficiently.
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Affiliation(s)
- R Mailler
- SIAAP (service public de l'assainissement francilien), Direction Innovation, Colombes, France
| | - J Pouillaude
- SIAAP (service public de l'assainissement francilien), Direction Innovation, Colombes, France
| | - Y Fayolle
- Université Paris-Saclay, INRAE, UR PROSE, Antony, France
| | - M Oliveira Filho
- SIAAP (service public de l'assainissement francilien), Direction Innovation, Colombes, France
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| | - C Causserand
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| | - V Rocher
- SIAAP (service public de l'assainissement francilien), Direction Innovation, Colombes, France
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Ma B, Ulbricht M, Hu C, Fan H, Wang X, Pan YR, Hosseini SS, Panglisch S, Van der Bruggen B, Wang Z. Membrane Life Cycle Management: An Exciting Opportunity for Advancing the Sustainability Features of Membrane Separations. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:3013-3020. [PMID: 36786864 DOI: 10.1021/acs.est.2c09257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Membrane science and technology is growing rapidly worldwide and continues to play an increasingly important role in diverse fields by offering high separation efficiency with low energy consumption. Membranes have also shown great promise for "green" separation. A majority of the investigations in the field are devoted to the membrane fabrication and modification with the ultimate goals of enhancing the properties and separation performance of membranes. However, less attention has been paid to membrane life cycle management, particularly at the end of service. This is becoming very important, especially taking into account the trends toward sustainable development and carbon neutrality. On the contrary, this can be a great opportunity considering the large variety of membrane processes, especially in terms of the size and capacity of plants in operation. This work aims to highlight the prominent aspects that govern membrane life cycle management with special attention to life cycle assessment (LCA). While fabrication, application, and recycling are the three key aspects of LCA, we focus here on membrane (module) recycling at the end of life by elucidating the relevant aspects, potential criteria, and strategies that effectively contribute to the achievement of green development and sustainability goals.
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Affiliation(s)
- Baiwen Ma
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Lehrstuhl für Technische Chemie II, Universität Duisburg-Essen, Essen 45117, Germany
| | - Mathias Ulbricht
- Lehrstuhl für Technische Chemie II, Universität Duisburg-Essen, Essen 45117, Germany
| | - Chengzhi Hu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Hongwei Fan
- College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Xu Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Yi-Rong Pan
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Seyed Saeid Hosseini
- Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
- Institute for Nanotechnology and Water Sustainability, College of Science, Engineering and Technology, University of South Africa, Johannesburg 1709, South Africa
| | - Stefan Panglisch
- Chair for Mechanical Process Engineering/Water Technology, University of Duisburg-Essen, Duisburg 47057, Germany
| | - Bart Van der Bruggen
- Department of Chemical Engineering, KU Leuven, Celestijnenlaan 200F, B-3001 Heverlee, Belgium
| | - Zhiwei Wang
- State Key Laboratory of Pollution Control and Resource Reuse, Shanghai Institute of Pollution Control and Ecological Security, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
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Tan DY, Hashimoto T, Takizawa S. 3D modeling of PVDF membrane aging using scanning electron microscope and OpenCV image analysis. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2022.121141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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6
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Boussouga YA, Than H, Schäfer AI. Selenium species removal by nanofiltration: Determination of retention mechanisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 829:154287. [PMID: 35248638 DOI: 10.1016/j.scitotenv.2022.154287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 02/28/2022] [Accepted: 02/28/2022] [Indexed: 06/14/2023]
Abstract
Selenium (Se) is a dissolved oxyanion drinking water contaminant requiring appropriate removal technologies. The removal of selenite (SeIV) and selenite (SeVI) with nanofiltration (NF) was investigated with an emphasis on the role of Se speciation and membrane charge screening on the retention mechanisms. The pH (2 to 12) showed strong pH dependence of Se retention, which was due to the speciation. No significant impact of salinity was observed by increasing NaCl concentration from 0.58 to 20 g/L. Application of the Donnan steric pore partitioning model with dielectric exclusion (DSPM-DE) showed that Donnan exclusion was the dominant retention mechanism for the oxyanions Se species. Nine different organic matter (OM) types were investigated at 10 mgC/L to determine if OM affects Se retention. Only OM characterised by negatively charged fractions, such as humic acid (HA), enhanced Se retention with NF270 of up to 20% for SeIV and 10% for SeVI. This was explained by enhanced Donnan exclusion. NF270 was effective in removing Se from real water (Gahard groundwater, Ille et Vilaine, France). The EU guideline (20 μg/L) of Se in drinking water was achieved with comparable performance to OM-free experiments using synthetic waters.
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Affiliation(s)
- Youssef-Amine Boussouga
- Institute for Advanced Membrane Technology (IAMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
| | - Hieu Than
- Institute for Advanced Membrane Technology (IAMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Andrea I Schäfer
- Institute for Advanced Membrane Technology (IAMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
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Jarvis P, Carra I, Jafari M, Judd SJ. Ceramic vs polymeric membrane implementation for potable water treatment. WATER RESEARCH 2022; 215:118269. [PMID: 35298992 DOI: 10.1016/j.watres.2022.118269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 02/28/2022] [Accepted: 03/05/2022] [Indexed: 06/14/2023]
Abstract
The continued technological developments and decreased purchase costs of ceramic membranes have seen increased recent interest in the technology as an alternative to the more widely used polymeric membranes. This paper assesses the relative technical, practical and economic merits of the two membrane materials in the context of potable water production from surface water sources. The work focuses on phenomena of direct technoeconomic significance, namely cleaning efficacy (manifested as permeability recovery), membrane integrity and incurred labour effort. Topics reviewed thus comprise: (a) practical comparison of the two technologies challenged with the same feedwater, (b) comparative technoeconomic analyses, (c) membrane integrity studies of polymeric membranes - incorporating aged samples extracted from operating installations, (d) sludging incidents, and (e) pilot and full-scale data. Available relevant data reveal: (a) bench-scale comparative tests do not indicate a consistent significant difference in the net permeability between the two membranes; (b) polymeric membranes are subject to a decline in both mechanical strength and permeability from the loss of the hydrophilic agent over a period of years from the action of hypochlorite used for cleaning; (c) the decreased mechanical strength with age of polymeric membranes increases the manual repair requirement and shortens membrane life, respectively impacting on labour and membrane replacement costs where the latter is also determined by the permeability; (d) the chemical and mechanical robustness of ceramic membranes permits more aggressive chemical cleaning, which then affects the chemicals consumption cost; and (e) anecdotal evidence suggests that polymeric membranes challenged with pre-coagulated surface waters may be subject to sludging, the agglomeration of solids in the membrane channels, which may also be age-related. Notwithstanding the above, data from published comparative technoeconomic studies indicate a linear relationship between the overall cost benefit and the membrane module cost ratio mitigated by the relative membrane life and operating flux.
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Affiliation(s)
- P Jarvis
- Cranfield Water Science Institute, Cranfield University, Beds, UK
| | - I Carra
- Cranfield Water Science Institute, Cranfield University, Beds, UK
| | - M Jafari
- PWNT, Velserbroek, the Netherland
| | - S J Judd
- Cranfield Water Science Institute, Cranfield University, Beds, UK.
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Membrane aging effects on water recovery during full-scale potable reuse: Mathematical optimization of backwashing frequency for constant-flux microfiltration. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2021.120294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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9
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Effects of Chemical Cleaning on the Ageing of Polyvinylidene Fluoride Microfiltration and Ultrafiltration Membranes Fouled with Organic and Inorganic Matter. MEMBRANES 2022; 12:membranes12030280. [PMID: 35323755 PMCID: PMC8954782 DOI: 10.3390/membranes12030280] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/23/2022] [Accepted: 02/25/2022] [Indexed: 11/17/2022]
Abstract
Herein, the effects of cleaning with sodium hydroxide and citric acid solutions as cleaning reagents on the changes in the properties of two hollow-fiber PVDF microfiltration (MF) and ultrafiltration (UF) membranes fouled with organic and inorganic matter were investigated. Accelerated membrane ageing was induced by use of high concentrations of tannic acid and iron oxide (Fe2O3) particles in the feed water; these conditions were kept with different membrane soaking times to observe temporal effects. It was found that tannic acid molecules adsorb onto the membrane surface that results in changes in surface characteristics, particularly surface functional groups that are responsible for enhancing membrane’s hydrophilicity. Experimental results demonstrate that NaOH had a stronger effect on the tensile strength and surface chemistry of the fouled MF and UF membranes than citric acid. Prediction of lifetime by an exponential (decay) model confirmed that the UF membrane cleaned with NaOH would be aged within about 1.8 years and the MF membrane after about 5 years, at cleaning every 15 days, downtime 2 h per cleaning, when a 10% tensile strength decrease against the original membrane is allowed.
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Oliveira Filho M, Mailler R, Rocher V, Fayolle Y, Causserand C. Comprehensive study of supported PVDF membrane ageing in MBR: A direct comparison between changes at bench scale and full scale. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119695] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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11
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Prediction of Membrane Failure in a Water Purification Plant Using Nonhomogeneous Poisson Process Models. MEMBRANES 2021; 11:membranes11110800. [PMID: 34832028 PMCID: PMC8624650 DOI: 10.3390/membranes11110800] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 10/19/2021] [Accepted: 10/19/2021] [Indexed: 12/27/2022]
Abstract
The prediction of membrane failure in full-scale water purification plants is an important but difficult task. Although previous studies employed accelerated laboratory-scale tests of membrane failure, it is not possible to reproduce the complex operational conditions of full-scale plants. Therefore, we aimed to develop prediction models of membrane failure using actual membrane failure data. Because membrane filtration systems are repairable systems, nonhomogeneous Poisson process (NHPP) models, i.e., power law and log-linear models, were employed; the model parameters were estimated using the membrane failure data from a full-scale plant operated for 13 years. Both models were able to predict cumulative failures for forthcoming years; nonetheless, the power law model showed higher stability and narrower confidence intervals than the log-linear model. By integrating two membrane replacement criteria, namely deterioration of filtrate water quality and reduction of membrane permeability, it was possible to predict the time to replace all the membranes on a water purification plant. Finally, the NHPP models coupled with a nonparametric bootstrap method provided a method to select membrane modules for earlier replacement than others. Although the criteria for membrane replacement may vary among membrane filtration plants, the NHPP models presented in this study could be applied to any other plant with membrane failure data.
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Jacquet N, Wurtzer S, Darracq G, Wyart Y, Moulin L, Moulin P. Effect of concentration on virus removal for ultrafiltration membrane in drinking water production. J Memb Sci 2021. [DOI: 10.1016/j.memsci.2021.119417] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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13
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Aumeier BM, Vollmer F, Lenfers S, Yüce S, Wessling M. Polymeric Membranes With Sufficient Thermo‐Mechanical Stability to Deploy Temperature Enhanced Backwash. CHEM-ING-TECH 2021. [DOI: 10.1002/cite.202100020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Benedikt M. Aumeier
- RWTH Aachen University Aachener Verfahrenstechnik Chemical Process Engineering Forckenbeckstraße 51 52074 Aachen Germany
- RWTH Aachen University Institute of Environmental Engineering Mies-van-der-Rohe Straße 1 52074 Aachen Germany (current address)
| | - Fabian Vollmer
- RWTH Aachen University Aachener Verfahrenstechnik Chemical Process Engineering Forckenbeckstraße 51 52074 Aachen Germany
| | - Simon Lenfers
- RWTH Aachen University Aachener Verfahrenstechnik Chemical Process Engineering Forckenbeckstraße 51 52074 Aachen Germany
| | - Süleyman Yüce
- RWTH Aachen University Aachener Verfahrenstechnik Chemical Process Engineering Forckenbeckstraße 51 52074 Aachen Germany
| | - Matthias Wessling
- RWTH Aachen University Aachener Verfahrenstechnik Chemical Process Engineering Forckenbeckstraße 51 52074 Aachen Germany
- DWI Leibniz Institute for Interactive Materials Forckenbeckstraße 50 52074 Aachen Germany
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Yu H, Chang H, Li X, Zhou Z, Song W, Ji H, Liang H. Long-term fouling evolution of polyvinyl chloride ultrafiltration membranes in a hybrid short-length sedimentation/ ultrafiltration process for drinking water production. J Memb Sci 2021. [DOI: 10.1016/j.memsci.2021.119320] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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15
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Li K, Su Q, Li S, Wen G, Huang T. Aging of PVDF and PES ultrafiltration membranes by sodium hypochlorite: Effect of solution pH. J Environ Sci (China) 2021; 104:444-455. [PMID: 33985746 DOI: 10.1016/j.jes.2020.12.020] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 12/01/2020] [Accepted: 12/16/2020] [Indexed: 06/12/2023]
Abstract
Sodium hypochlorite (NaClO) is a commonly applied cleaning agent for ultrafiltration membranes in water and wastewater treatment. Long-term exposure to NaClO might change the properties and performance of polymeric membranes, and ultimately shorten membrane lifespan. Active species in NaClO solution vary with solution pH, and the aging effects can change depending on the membrane material. In this study, the aging of polyvinylidene fluoride (PVDF) and polyethersulfone (PES) membranes by NaClO at pH 3-11 was investigated by examining variations in chemical composition, surface charge, surface morphology, mechanical strength, permeability, and retention ability. Polyvinyl pyrrolidone (PVP), which was blended in both membranes, was oxidized and dislodged due to NaClO aging at all investigated pH values, but the oxidation products and dislodgement ratio of PVP varied with solution pH. For the PVDF membrane, NaClO aging at pH 3-11 caused a moderate increase in permeability and decreased retention due to the oxidation and release of PVP. The tensile strength decreased only at pH 11 because of the defluorination of PVDF molecules. For the PES membrane, NaClO aging at all investigated pH resulted in chain scission of PES molecules, which was favored at pH 7 and 9, potentially due to the formation of free radicals. Therefore, a decrease in tensile strength and retention ability, as well as an increase in permeability, occurred in the PES membrane for NaClO aging at pH 3-11. Overall, the results can provide a basis for selecting chemical cleaning conditions for PVDF and PES membranes.
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Affiliation(s)
- Kai Li
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Qian Su
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Shu Li
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Gang Wen
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Tinglin Huang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
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Zhang Y, Wang T, Meng J, Lei J, Zheng X, Wang Y, Zhang J, Cao X, Li X, Qiu X, Xue J. A novel conductive composite membrane with polypyrrole (PPy) and stainless-steel mesh: Fabrication, performance, and anti-fouling mechanism. J Memb Sci 2021. [DOI: 10.1016/j.memsci.2020.118937] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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17
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18
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Bouhid de Aguiar I, Schroën K. Microfluidics Used as a Tool to Understand and Optimize Membrane Filtration Processes. MEMBRANES 2020; 10:E316. [PMID: 33138236 PMCID: PMC7692330 DOI: 10.3390/membranes10110316] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 10/27/2020] [Accepted: 10/28/2020] [Indexed: 12/13/2022]
Abstract
Membrane filtration processes are best known for their application in the water, oil, and gas sectors, but also in food production they play an eminent role. Filtration processes are known to suffer from a decrease in efficiency in time due to e.g., particle deposition, also known as fouling and pore blocking. Although these processes are not very well understood at a small scale, smart engineering approaches have been used to keep membrane processes running. Microfluidic devices have been increasingly applied to study membrane filtration processes and accommodate observation and understanding of the filtration process at different scales, from nanometer to millimeter and more. In combination with microscopes and high-speed imaging, microfluidic devices allow real time observation of filtration processes. In this review we will give a general introduction on microfluidic devices used to study membrane filtration behavior, followed by a discussion of how microfluidic devices can be used to understand current challenges. We will then discuss how increased knowledge on fundamental aspects of membrane filtration can help optimize existing processes, before wrapping up with an outlook on future prospects on the use of microfluidics within the field of membrane separation.
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Affiliation(s)
- Izabella Bouhid de Aguiar
- Membrane Science and Technology—Membrane Processes for Food, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands;
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