1
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Ran N, Sharon-Gojman R, Larsson S, Gillor O, Mauter MS, Herzberg M. Unraveling pH Effects on Ultrafiltration Membrane Fouling by Extracellular Polymeric Substances: Adsorption and Conformation Analyzed with Localized Surface Plasmon Resonance. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:14763-14773. [PMID: 36197031 DOI: 10.1021/acs.est.2c03085] [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: 06/16/2023]
Abstract
Extracellular polymeric substances (EPSs) can conform and orient on the surface according to the applied aquatic conditions. While pH elevation usually removes EPSs from membranes, small changes in pH can change the adsorbed EPS conformation and orientation, resulting in a decrease in membrane permeability. Accordingly, EPS layers were tested with localized surface plasmon resonance (LSPR) sensing and quartz crystal microbalance with dissipation monitoring (QCM-D) using a hybrid sensor. A novel membrane-mimetic hybrid QCM-D-LSPR sensor was designed to indicate both "dry" mass and mechanical load ("wet" mass) of the adsorbed EPS. The effect of pH on the EPS layer's viscoelastic properties and hydrated thickness analyzed by QCM-D corroborates with the shift in EPS areal concentration, ΓS, and the associated EPS conformation, analyzed by LSPR. As pH elevates, the processes of (i) elevation in EPS layer's thickness (QCM-D) and (ii) decrease in the EPS areal density, ΓS (LSPR), provide a clear indication for changes in EPS conformation, which decrease the effective ultrafiltration (UF) membrane pore diameter. This decrease in the pore diameter together with the increase in surface hydrophobicity elevates UF membrane hydraulic resistance.
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Affiliation(s)
- Noya Ran
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben Gurion University of the Negev, Sede Boqer Campus, 84990 Midreshet Ben Gurion, Israel
| | - Revital Sharon-Gojman
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben Gurion University of the Negev, Sede Boqer Campus, 84990 Midreshet Ben Gurion, Israel
| | - Sara Larsson
- Insplorion AB, Arvid Wallgrens backe 20, 413 46 Göteborg, Sweden
| | - Osnat Gillor
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben Gurion University of the Negev, Sede Boqer Campus, 84990 Midreshet Ben Gurion, Israel
| | - Meagan S Mauter
- Civil and Environmental Engineering, Stanford University, Stanford, California 94305, United States
| | - Moshe Herzberg
- Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben Gurion University of the Negev, Sede Boqer Campus, 84990 Midreshet Ben Gurion, Israel
- Civil and Environmental Engineering, Stanford University, Stanford, California 94305, United States
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2
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Rolf J, Cao T, Huang X, Boo C, Li Q, Elimelech M. Inorganic Scaling in Membrane Desalination: Models, Mechanisms, and Characterization Methods. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:7484-7511. [PMID: 35666637 DOI: 10.1021/acs.est.2c01858] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Inorganic scaling caused by precipitation of sparingly soluble salts at supersaturation is a common but critical issue, limiting the efficiency of membrane-based desalination and brine management technologies as well as other engineered systems. A wide range of minerals including calcium carbonate, calcium sulfate, and silica precipitate during membrane-based desalination, limiting water recovery and reducing process efficiency. The economic impact of scaling on desalination processes requires understanding of its sources, causes, effects, and control methods. In this Critical Review, we first describe nucleation mechanisms and crystal growth theories, which are fundamental to understanding inorganic scale formation during membrane desalination. We, then, discuss the key mechanisms and factors that govern membrane scaling, including membrane properties, such as surface roughness, charge, and functionality, as well as feedwater characteristics, such as pH, temperature, and ionic strength. We follow with a critical review of current characterization techniques for both homogeneous and heterogeneous nucleation, focusing on the strengths and limitations of each technique to elucidate scale-inducing mechanisms, observe actual crystal growth, and analyze the outcome of scaling behaviors of desalination membranes. We conclude with an outlook on research needs and future research directions to provide guidelines for scale mitigation in water treatment and desalination.
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Affiliation(s)
- Julianne Rolf
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
- Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment (NEWT), Yale University, New Haven, Connecticut 06520-8286, United States
| | - Tianchi Cao
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
| | - Xiaochuan Huang
- Department of Civil and Environmental Engineering, Rice University, MS-519, 6100 Main Street, Houston, Texas 77005, United States
- Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment (NEWT), Rice University, MS 6398, 6100 Main Street, Houston 77005, United States
| | - Chanhee Boo
- Water Cycle Research Center, National Agenda Research Division, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Qilin Li
- Department of Civil and Environmental Engineering, Rice University, MS-519, 6100 Main Street, Houston, Texas 77005, United States
- Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment (NEWT), Rice University, MS 6398, 6100 Main Street, Houston 77005, United States
| | - Menachem Elimelech
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
- Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment (NEWT), Yale University, New Haven, Connecticut 06520-8286, United States
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3
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Rathinam K, Modi A, Schwahn D, Oren Y, Kasher R. Surface grafting with diverse charged chemical groups mitigates calcium phosphate scaling on reverse osmosis membranes during municipal wastewater desalination. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2022.120310] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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4
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Polyethylene-supported nanofiltration membrane with in situ formed surface patterns of millimeter size in resisting fouling. J Memb Sci 2021. [DOI: 10.1016/j.memsci.2020.118830] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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5
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Huang X, Li C, Zuo K, Li Q. Predominant Effect of Material Surface Hydrophobicity on Gypsum Scale Formation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:15395-15404. [PMID: 33064949 DOI: 10.1021/acs.est.0c03826] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Scale formation is an important challenge in water and wastewater treatment systems. However, due to the complex nature of membrane surfaces, the effects of specific membrane surface characteristics on scale formation are poorly understood. In this study, the independent effect of surface hydrophobicity on gypsum (CaSO4·2H2O) scale formation via surface-induced nucleation and bulk homogeneous nucleation was investigated using quartz crystal microbalance with dissipation (QCM-D) on self-assembled monolayers (SAMs) terminated with -OH, -CH3, and -CF3 functional groups. Results show that higher surface hydrophobicity enhances both surface-induced nucleation of gypsum and attachment of gypsum crystals formed from homogeneous nucleation in the bulk solution. The enhanced surface-induced nucleation is attributed to the lower nucleation energy barrier on a hydrophobic surface, while the increased gypsum crystal attachment results from the favorable hydrophobic interactions between gypsum and more hydrophobic surfaces. Contrary to previous findings, the role of Ca2+ adsorption in surface-induced nucleation was found to be relatively small and similar on the different SAMs. Therefore, increasing material hydrophilicity is a potential approach to reduce gypsum scaling.
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Affiliation(s)
- Xiaochuan Huang
- Department of Civil and Environmental Engineering, Rice University, MS-519, 6100 Main Street, Houston 77005, United States
- NSF Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, Rice University, MS-6398, 6100 Main Street, Houston 77005, United States
| | - Chen Li
- Department of Civil and Environmental Engineering, Rice University, MS-519, 6100 Main Street, Houston 77005, United States
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Kuichang Zuo
- Department of Civil and Environmental Engineering, Rice University, MS-519, 6100 Main Street, Houston 77005, United States
- NSF Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, Rice University, MS-6398, 6100 Main Street, Houston 77005, United States
| | - Qilin Li
- Department of Civil and Environmental Engineering, Rice University, MS-519, 6100 Main Street, Houston 77005, United States
- NSF Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, Rice University, MS-6398, 6100 Main Street, Houston 77005, United States
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6
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Pipich V, Dickmann M, Frielinghaus H, Kasher R, Hugenschmidt C, Petry W, Oren Y, Schwahn D. Morphology of Thin Film Composite Membranes Explored by Small-Angle Neutron Scattering and Positron-Annihilation Lifetime Spectroscopy. MEMBRANES 2020; 10:membranes10030048. [PMID: 32197524 PMCID: PMC7142468 DOI: 10.3390/membranes10030048] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 03/16/2020] [Accepted: 03/16/2020] [Indexed: 12/05/2022]
Abstract
The morphology of thin film composite (TFC) membranes used in reverse osmosis (RO) and nanofiltration (NF) water treatment was explored with small-angle neutron scattering (SANS) and positron-annihilation lifetime spectroscopy (PALS). The combination of both methods allowed the characterization of the bulk porous structure from a few Å to µm in radius. PALS shows pores of ~4.5 Å average radius in a surface layer of about 4 μm thickness, which become ~40% smaller at the free surface of the membranes. This observation may correlate with the glass state of the involved polymer. Pores of similar size appear in SANS as closely packed pores of ~6 Å radius distributed with an average distance of ~30 Å. The main effort of SANS was the characterization of the morphology of the porous polysulfone support layer as well as the fibers of the nonwoven fabric layer. Contrast variation using the media H2O/D2O and supercritical CO2 and CD4 identified the polymers of the support layers as well as internal heterogeneities.
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Affiliation(s)
- Vitaliy Pipich
- Jülich Centre for Neutron Science JCNS-FRM II; Outstation at FRM II, Lichtenbergstr. 1, D-85747 Garching, Germany; (V.P.); (H.F.)
| | - Marcel Dickmann
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstr. 1, D-85748 Garching, Germany; (M.D.); (C.H.); (W.P.)
| | - Henrich Frielinghaus
- Jülich Centre for Neutron Science JCNS-FRM II; Outstation at FRM II, Lichtenbergstr. 1, D-85747 Garching, Germany; (V.P.); (H.F.)
| | - Roni Kasher
- Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 84990, Israel; (R.K.); (Y.O.)
| | - Christoph Hugenschmidt
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstr. 1, D-85748 Garching, Germany; (M.D.); (C.H.); (W.P.)
| | - Winfried Petry
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstr. 1, D-85748 Garching, Germany; (M.D.); (C.H.); (W.P.)
| | - Yoram Oren
- Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 84990, Israel; (R.K.); (Y.O.)
| | - Dietmar Schwahn
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstr. 1, D-85748 Garching, Germany; (M.D.); (C.H.); (W.P.)
- Correspondence:
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7
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Dou P, Zhao S, Xu S, Li XM, He T. Feasibility of osmotic dilution for recycling spent dialysate: Process performance, scaling, and economic evaluation. WATER RESEARCH 2020; 168:115157. [PMID: 31614235 DOI: 10.1016/j.watres.2019.115157] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 09/25/2019] [Accepted: 10/03/2019] [Indexed: 06/10/2023]
Abstract
Hemodialysis is one of the therapies for patients with kidney failure. Hemodialysis requires large amounts of pure water, and is one of the most water-hungry medical procedures, and thus represents a clear opportunity where improvements should be made concerning the consumption and wastage of water. In this paper, we explored the potential of forward osmosis (FO) membrane for recycling the spent dialysate using the dialysis concentrate as the draw solution. Partially diluted dialysis concentrate could be further diluted with pure water to form dialysate for further dialysis process. Using commercial cellulose triacetate (CTA) FO membranes, the water recovery of approximately 64% was achieved and the final volume of the partially diluted dialysis concentrate was about four times the initial volume. Flux decline of the FO process was observed, mainly due to concentration of synthetic spent dialysate and dilution of dialysis concentrate, while membrane scaling had little impact on the flux decline. The urea rejection was found to be relatively low owing to the small size and electroneutral nature of the urea molecule. Obvious membrane scaling was observed after three FO cycles. The energy dispersive spectroscopy analysis of the scaling layer indicated that the scalants were phosphates and carbonates. The scaling was removed via osmotic backwash and almost completely recovery of FO flux was obtained. Economic analysis showed that the centralized treatment of spent dialysate in a dialysis center using the proposed osmotic dilution process could greatly save water resources and cost. Improving the urea rejection of FO membrane was identified as an important research focus for future research on the potential application of FO technology for recycling the spent dialysate in hemodialysis.
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Affiliation(s)
- Pengjia Dou
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201210, China; University of Chinese Academy of Sciences, Beijing, 100049, China; School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Shuwei Zhao
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201210, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shanshan Xu
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201210, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xue-Mei Li
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201210, China
| | - Tao He
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201210, China; School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China.
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8
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Ye H, Chen D, Li N, Xu Q, Li H, He J, Lu J. Durable and Robust Self-Healing Superhydrophobic Co-PDMS@ZIF-8-Coated MWCNT Films for Extremely Efficient Emulsion Separation. ACS APPLIED MATERIALS & INTERFACES 2019; 11:38313-38320. [PMID: 31552730 DOI: 10.1021/acsami.9b13539] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The discharge of large amounts of sewage has caused enormous damage to the environment and human health. There is an urgent need for efficient and environmentally friendly materials to deal with such troubles. Materials with emulsion separation have attracted everyone's attention. In this study, zeolitic imidazolate framework (ZIF)-8- and Co-polydimethylsiloxane (PDMS)-modified multiwalled carbon nanotube films were fabricated. First, the surface of the nanotube films was modified with ZIF-8 by in situ growth, and then a Co-PDMS layer was added by dip coating. The membrane has excellent wettability, and it is superhydrophobic and superoleophilic in air. The separation efficiency of water-in-oil emulsions reaches more than 99.9%, and it has an outstanding separation ability for corrosive emulsions. Moreover, the membrane has an excellent self-healing ability, and it can rapidly heal at normal temperature after being damaged. This makes the film more suitable for practical oily wastewater treatment. We performed related research and propose a possible self-healing mechanism.
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Affiliation(s)
- Hanchen Ye
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , Suzhou 215123 , China
| | - Dongyun Chen
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , Suzhou 215123 , China
| | - Najun Li
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , Suzhou 215123 , China
| | - Qingfeng Xu
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , Suzhou 215123 , China
| | - Hua Li
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , Suzhou 215123 , China
| | - Jinghui He
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , Suzhou 215123 , China
| | - Jianmei Lu
- College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Suzhou Nano Science and Technology , Soochow University , Suzhou 215123 , China
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9
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Kaganovich M, Zhang W, Freger V, Bernstein R. Effect of the membrane exclusion mechanism on phosphate scaling during synthetic effluent desalination. WATER RESEARCH 2019; 161:381-391. [PMID: 31226537 DOI: 10.1016/j.watres.2019.06.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 06/01/2019] [Accepted: 06/05/2019] [Indexed: 06/09/2023]
Abstract
Calcium phosphate scaling is one of the main limitations in effluent desalination using membranes. This may be overcome by tailoring membranes with lower rejection of the scalant ions. In this study, we systematically examined the use of negatively and positively charged membranes, rejecting ions mainly based on Donnan exclusion, as a low-scaling alternative to dielectric-exclusion-dominated polyamide NF membranes for effluent desalination. The two charged membranes exhibited a lower calcium and especially phosphate rejection than the polyamide membrane. Consequently, the calcium phosphate supersaturation and then the propensity to scaling of the charged membranes were much lower than the polyamide membrane. This also allowed filtering at a much higher recovery ratio with the charged membranes. It was also found that, despite the fact that the charged membranes had an opposite fixed charge, their scaling behavior was similar. Apparently, although these membranes showed opposite selectivity towards scalant ions (phosphate and calcium) in single salt solutions, the rejection pattern in mixed salt solutions resulted in similar saturation indices, much lower than for polyamide membrane. The scale formed on all three membranes was identified as amorphous calcium phosphate (ACP), although its saturation index was lower than its solubility factor. This was explained by concentration polarization which increases the saturation index in the solution adjacent to the membrane surface. Tests in absence of permeate flux showed a much slower precipitation that took a few days compared with filtration conditions (few hours). In addition, under these conditions, the effect of the scaling on the membrane permeability was generally reduced and the scale contained crystalline calcium phosphate products, different from ACP. The results indicate that the ion rejection and resulting polarization next to the membrane surface plays a crucial role in scaling. Thus, tuning ion selectivity of NF membranes towards scalant ions presents a promising alternative for scaling mitigation during effluent desalination.
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Affiliation(s)
- Michaela Kaganovich
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus 84990, Israel
| | - Wei Zhang
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus 84990, Israel
| | - Viatcheslav Freger
- Wolfson Department of Chemical Engineering, Technion - Israel Institute of Technology, Technion City, 32000, Haifa, Israel
| | - Roy Bernstein
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus 84990, Israel.
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10
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Mineral scaling in membrane desalination: Mechanisms, mitigation strategies, and feasibility of scaling-resistant membranes. J Memb Sci 2019. [DOI: 10.1016/j.memsci.2019.02.049] [Citation(s) in RCA: 118] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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11
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Rathinam K, Abraham S, Oren Y, Schwahn D, Petry W, Kaufman Y, Kasher R. Surface-Induced Silica Scaling during Brackish Water Desalination: The Role of Surface Charge and Specific Chemical Groups. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:5202-5211. [PMID: 30955329 DOI: 10.1021/acs.est.8b06154] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Silica scaling of membranes used in reverse osmosis desalination processes is a severe problem, especially during the desalination of brackish groundwater due to high silica concentrations. This problem limits the water supply in inland arid and semiarid regions. Here, we investigated the influence of surface-exposed organic functional groups on silica precipitation and scaling. A test solution simulating the mineral content of brackish groundwater desalination brine at 75% recovery was used. The mass and chemical composition of the precipitated silica was monitored using a quartz crystal microbalance, X-ray photoelectron spectroscopy, and infrared spectroscopy, showing that surfaces with positively charged groups induced rapid silica precipitation, and the rate of silica precipitation followed the order -NH2 ∼ -N+(CH3)3 > -NH2/-COOH > -H2PO3 ∼ -OH > -COOH > -CH3. Force vs distance AFM measurements showed that the adhesion energy between a silica colloid glued to AFM cantilever and the studied surfaces increased as the surface charge changed from negative to positive. Thus, for the first time direct measurements of molecular forces and specific chemical groups that govern silica scaling during brackish water desalination is reported here. The influence of the different functional groups and the effect of the surface charge on silica precipitation that were found here can be used to design membranes that resist silica scaling in membrane-based desalination processes.
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Affiliation(s)
- Karthik Rathinam
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, The Blaustein Institutes for Desert Research , Ben-Gurion University of the Negev , Sde Boqer Campus , Midreshet Ben-Gurion 8499000 , Israel
| | - Shiju Abraham
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, The Blaustein Institutes for Desert Research , Ben-Gurion University of the Negev , Sde Boqer Campus , Midreshet Ben-Gurion 8499000 , Israel
| | - Yoram Oren
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, The Blaustein Institutes for Desert Research , Ben-Gurion University of the Negev , Sde Boqer Campus , Midreshet Ben-Gurion 8499000 , Israel
| | - Dietmar Schwahn
- Technische Universität München , Forschungs-Neutronenquelle, Heinz Maier-Leibnitz (FRM II) , James-Franck-Straße 1 , D-85748 Garching , Germany
| | - Winfried Petry
- Technische Universität München , Forschungs-Neutronenquelle, Heinz Maier-Leibnitz (FRM II) , James-Franck-Straße 1 , D-85748 Garching , Germany
| | - Yair Kaufman
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, The Blaustein Institutes for Desert Research , Ben-Gurion University of the Negev , Sde Boqer Campus , Midreshet Ben-Gurion 8499000 , Israel
| | - Roni Kasher
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, The Blaustein Institutes for Desert Research , Ben-Gurion University of the Negev , Sde Boqer Campus , Midreshet Ben-Gurion 8499000 , Israel
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12
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Rathinam K, Oren Y, Petry W, Schwahn D, Kasher R. Calcium phosphate scaling during wastewater desalination on oligoamide surfaces mimicking reverse osmosis and nanofiltration membranes. WATER RESEARCH 2018; 128:217-225. [PMID: 29107906 DOI: 10.1016/j.watres.2017.10.055] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 10/19/2017] [Accepted: 10/26/2017] [Indexed: 06/07/2023]
Abstract
Desalinated domestic wastewater is an indispensable water resource in arid regions; however, its recovery can be limited by calcium phosphate scaling and fouling of the membrane. Here we investigated calcium phosphate mineralization on oligoamide surfaces that mimics reverse osmosis (RO) and nanofiltration (NF) membrane surfaces. We used a solution that simulates desalination of secondary treated domestic wastewater effluents for calcium phosphate mineralization experiments with oligoamide-coated gold surfaces. Attenuated total reflection-Fourier transform infrared spectroscopy and energy dispersive spectrometry showed that calcium phosphate and carbonate precipitated on RO mimetic surfaces. The rate of precipitation on oligoamide sensors was monitored by a quartz crystal microbalance, showing that scaling was more intense on the RO than the NF mimetic surface and that excessive carboxyl functional groups on both surfaces promoted scaling. Filtration experiments of similar solutions with commercial membranes showed that scaling was more intense on the RO membranes than on the NF membranes, which supported the results obtained with the oligoamide model surfaces. The results of this study can be implemented in developing RO and NF membranes to prevent calcium phosphate scaling and consequently lower water-treatment costs of domestic wastewater treatment.
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Affiliation(s)
- Karthik Rathinam
- Department of Desalination and Water Treatment, The Zuckerberg Institute for Water Research, The Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 84990, Israel
| | - Yoram Oren
- Department of Desalination and Water Treatment, The Zuckerberg Institute for Water Research, The Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 84990, Israel
| | - Winfried Petry
- Technische Universität München, Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II), D-85748 Garching, Germany
| | - Dietmar Schwahn
- Technische Universität München, Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II), D-85748 Garching, Germany
| | - Roni Kasher
- Department of Desalination and Water Treatment, The Zuckerberg Institute for Water Research, The Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 84990, Israel.
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13
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Shaffer DL, Tousley ME, Elimelech M. Influence of polyamide membrane surface chemistry on gypsum scaling behavior. J Memb Sci 2017. [DOI: 10.1016/j.memsci.2016.11.003] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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14
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Sun Y, Tian J, Zhao Z, Shi W, Liu D, Cui F. Membrane fouling of forward osmosis (FO) membrane for municipal wastewater treatment: A comparison between direct FO and OMBR. WATER RESEARCH 2016; 104:330-339. [PMID: 27570134 DOI: 10.1016/j.watres.2016.08.039] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 08/18/2016] [Accepted: 08/20/2016] [Indexed: 06/06/2023]
Abstract
In this work, membrane fouling behavior in a direct forward osmosis (FO) and an osmotic membrane bioreactor (OMBR) for municipal wastewater treatment was systematically investigated and compared. During the long-term operation, much severer flux decline was observed for the direct FO than that for the OMBR. The cake layer was found to be much thicker, together with large amounts of microorganisms growing on the membrane surface in direct FO. Interestingly, no obvious attachment of microorganisms on the membrane surface was observed in the OMBR. The fourier transform infrared spectroscopy (FTIR) and excitation emission matrices (EEM) analyses showed the polysaccharides and proteins were the dominant organic foulants in the fouling layer, and the quantity of the organic substances was also higher in direct FO than that in OMBR. Energy-dispersive X-ray (EDX) results indicated the main inorganic elements in the fouling layer were Ca, Mg, Fe and P, all of which exhibited higher relative percentages in direct FO than that in OMBR. The occurrence of higher contents of microorganisms, organic foulants and inorganic elements in the cake layer caused a higher filtration resistance for the FO membrane in the direct FO. Although more severe membrane fouling was identified in direct FO, the hydraulic and chemical cleaning was more effective on recovering the water permeability of the membrane in direct FO than that in OMBR.
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Affiliation(s)
- Yan Sun
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jiayu Tian
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Zhiwei Zhao
- Department of National Defense Construction Planning and Environmental Engineering, Logistical Engineering University, Chongqing 401311, China
| | - Wenxin Shi
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Dongmei Liu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Fuyi Cui
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
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15
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Dahdal YN, Oren Y, Schwahn D, Pipich V, Herzberg M, Ying W, Kasher R, Rapaport H. Biopolymer-induced calcium phosphate scaling in membrane-based water treatment systems: Langmuir model films studies. Colloids Surf B Biointerfaces 2016; 143:233-242. [DOI: 10.1016/j.colsurfb.2016.02.047] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 02/21/2016] [Accepted: 02/23/2016] [Indexed: 11/25/2022]
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16
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Dahdal Y, Pipich V, Rapaport H, Oren Y, Kasher R, Schwahn D. Small-angle neutron scattering studies of alginate as biomineralizing agent and scale initiator. POLYMER 2016. [DOI: 10.1016/j.polymer.2016.01.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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17
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Membrane fouling and long-term performance of seawater-driven forward osmosis for enrichment of nutrients in treated municipal wastewater. J Memb Sci 2016. [DOI: 10.1016/j.memsci.2015.11.009] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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18
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Ying W, Kumar R, Herzberg M, Kasher R. Diminished swelling of cross-linked aromatic oligoamide surfaces revealing a new fouling mechanism of reverse-osmosis membranes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:6815-6822. [PMID: 25920584 DOI: 10.1021/es504325d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Swelling of the active layer of reverse osmosis (RO) membranes has an important effect on permeate water flux. The effects of organic- and biofouling on the swelling of the RO membrane active layer and the consequent changes of permeate flux are examined here. A cross-linked aromatic oligoamide film that mimics the surface chemistry of an RO polyamide membrane was synthesized stepwise on gold-coated surfaces. Foulant adsorption to the oligoamide film and its swelling were measured with a quartz crystal microbalance, and the effects of fouling on the membrane's performance were evaluated. The foulants were extracellular polymeric substances (EPS) extracted from fouled RO membranes and organic compounds of ultrafiltration permeate (UFP) from a membrane bioreactor used to treat municipal wastewater. The adsorbed foulants affected the swelling of the cross-linked oligoamide film differently. EPS had little effect on the swelling of the oligoamide film, whereas UFP significantly impaired swelling. Permeate flux declined more rapidly under UFP fouling than it did under EPS. Foulant adsorption was shown to diminish swelling of the aromatic oligoamide surfaces. Among the already known RO membrane fouling mechanisms, a novel RO fouling mechanism is proposed, in which foulant-membrane interactions hinder membrane swelling and thus increase hydraulic resistance.
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Affiliation(s)
- Wang Ying
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben-Gurion 84990, Israel
| | - Rajender Kumar
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben-Gurion 84990, Israel
| | - Moshe Herzberg
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben-Gurion 84990, Israel
| | - Roni Kasher
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, Midreshet Ben-Gurion 84990, Israel
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19
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He C, Tian Z, Zhang B, Lin Y, Chen X, Wang M, Li F. Inhibition Effect of Environment-Friendly Inhibitors on the Corrosion of Carbon Steel in Recirculating Cooling Water. Ind Eng Chem Res 2015. [DOI: 10.1021/ie504616z] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chengjun He
- State Key Lab of Pollution Control & Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Rd, Shanghai 200092, China
| | - Zhipeng Tian
- State Key Lab of Pollution Control & Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Rd, Shanghai 200092, China
| | - Bingru Zhang
- State Key Lab of Pollution Control & Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Rd, Shanghai 200092, China
- Key Laboratory of Yangtze Aquatic
Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, 1239 Siping Rd, Shanghai 200092, China
| | - Yu Lin
- State Key Lab of Pollution Control & Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Rd, Shanghai 200092, China
| | - Xi Chen
- State Key Lab of Pollution Control & Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Rd, Shanghai 200092, China
| | - Meijing Wang
- State Key Lab of Pollution Control & Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Rd, Shanghai 200092, China
| | - Fengting Li
- State Key Lab of Pollution Control & Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Rd, Shanghai 200092, China
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20
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Radu AI, Bergwerff L, van Loosdrecht MCM, Picioreanu C. Combined biofouling and scaling in membrane feed channels: a new modeling approach. BIOFOULING 2015; 31:83-100. [PMID: 25587632 DOI: 10.1080/08927014.2014.996750] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A mathematical model was developed for combined fouling due to biofilms and mineral precipitates in membrane feed channels with spacers. Finite element simulation of flow and solute transport in two-dimensional geometries was coupled with a particle-based approach for the development of a composite (cells and crystals) foulant layer. Three fouling scenarios were compared: biofouling only, scaling only and combined fouling. Combined fouling causes a quicker flux decline than the summed flux deterioration when scaling and biofouling act independently. The model results indicate that the presence of biofilms leads to more mineral formation due to: (1) an enhanced degree of saturation for salts next to the membrane and within the biofilm; and (2) more available surface for nucleation to occur. The impact of biofilm in accelerating gypsum precipitation depends on the composition of the feed water (eg the presence of NaCl) and the kinetics of crystal nucleation and growth. Interactions between flow, solute transport and biofilm-induced mineralization are discussed.
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Affiliation(s)
- A I Radu
- a Faculty of Applied Sciences, Department of Biotechnology , Delft University of Technology , Delft , The Netherlands
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21
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Dahdal YN, Pipich V, Rapaport H, Oren Y, Kasher R, Schwahn D. Small-angle neutron scattering studies of mineralization on BSA coated citrate capped gold nanoparticles used as a model surface for membrane scaling in RO wastewater desalination. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:15072-15082. [PMID: 25458085 DOI: 10.1021/la502706k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Bovine serum albumin (BSA) coated on citrate capped gold nanoparticles (BSA-GNPs) was exposed to a simulated wastewater effluent (SSE) in order to study the mineralization and thereby mimic scaling at biofouled membranes of reverse osmosis (RO) wastewater desalination plants. RO is a leading technology of achieving freshwater quality as it has the capability of removing both dissolved inorganic salts and organic contaminants from tertiary wastewater effluents. The aim was to better understand one of the major problems facing this technology which is fouling of the membranes, mainly biofouling and scaling by calcium phosphate. The experiments were performed using the small-angle neutron scattering (SANS) technique. The nanoparticles, GNPs, stabilized by the citrate groups showed 30 Å large particles having a homogeneous distribution of gold and citrate with a gold volume fraction of the order of 1%. On the average two BSA monomers are grafted at 2.4 GNPs. The exposed BSA-GNPs to SSE solution led to immediate mineralization of stable composite particles of the order of 0.2 μm diameter and a mineral volume fraction between 50% and 80%. The volume fraction of the mineral was of the order of 10(-5), which is roughly 3 times larger but an order of magnitude smaller than the maximum possible contents of respectively calcium phosphate and calcium carbonate in the SSE solution. Considering the extreme low solubility product of calcium phosphate, we suggest total calcium phosphate and partially (5-10%) calcium carbonate formation in the presence of BSA-GNPs.
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Affiliation(s)
- Y N Dahdal
- Zuckerberg Institute for Water Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev , Sede Boqer Campus, Beer-Sheva 8499000, Israel
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22
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Pipich V, Dahdal Y, Rapaport H, Kasher R, Oren Y, Schwahn D. Effects of biological molecules on calcium mineral formation associated with wastewater desalination as assessed using small-angle neutron scattering. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:7607-7617. [PMID: 23701483 DOI: 10.1021/la4001889] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Calcium phosphate scale formation on reverse osmosis (RO) membranes is one of the main limitations on cost-effective desalination of domestic wastewater worldwide. It has been shown that organic agents affect mineralization. In this study, we explored mineralization in the presence of two biofilm-relevant organic compounds, the proteins bovine serum albumin (BSA) and lysozyme, in a simulated secondary effluent (SSE) solution using small-angle neutron scattering (SANS), and applied the results to analyses of mineral precipitation in RO desalination of secondary effluents of wastewater. The two proteins are prominent members of bacterial extracellular polymeric substances (EPSs), forming biofilms that are frequently associated with RO-membrane fouling during wastewater desalination. Laboratory experiments showed that both proteins in SSE solution are involved in complex mineralization processes. Only small portions of both protein fractions are involved in mineralization processes, whereas most of the protein fractions remain as monomers in solution. Contrast variation showed that composite particles of mineral and protein are formed instantaneously to a radius of gyration of about 300 Å, coexisting with particles of about μm size. After about one day, these large particles start to grow again at the expense of the 300 Å particles. The volume fraction of the 300 Å particles is of the order of 2 × 10(-4), which is too large to represent calcium phosphate such as hydroxyapatite as the only mineral present. Considering the data of mineral volume fraction obtained here as well as the solubility product of possible mineral polymorphs in the SSE solution, we suggest the formation of protein-mineral particles of hydroxyapatite and calcium carbonate during scale formation.
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Affiliation(s)
- Vitaliy Pipich
- Jülich Centre for Neutron Science JCNS-FRM II, Outstation at FRM II, D-85747 Garching, Lichtenbergstrasse 1, Germany
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23
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Ke X, Hongqiang R, Lili D, Jinju G, Tingting Z. A review of membrane fouling in municipal secondary effluent reclamation. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2013; 20:771-777. [PMID: 22945660 DOI: 10.1007/s11356-012-1147-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Accepted: 08/27/2012] [Indexed: 06/01/2023]
Abstract
Reclamation of municipal secondary effluent for non-potable purposes is considered vital in alleviating the demand for existing limited water supplies while helping to protect remaining water sources from being polluted. In recent decades, reverse osmosis and nanofiltration membrane technologies have become increasingly attractive for reclamation of municipal secondary effluent because they are highly efficient, easy to operate, and economical. However, membrane fouling is a major obstacle in the development of membrane technology in municipal secondary effluent reclamation. This paper reviews three types of membrane fouling in municipal secondary effluent reclamation, namely, effluent organic matter (EfOM) membrane fouling, microbial membrane fouling, and inorganic membrane fouling, as well as their correlation. Membrane fouling by EfOM and microbes are found to be severe, and they are significantly correlated. Most previous studies conducted laboratory-scale experiments of membrane fouling with model organic matters and bacteria, but these model organic matters and bacteria might still be unrepresentative. More studies on membrane fouling in municipal secondary effluent reclamation with actual wastewater are essential.
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Affiliation(s)
- Xu Ke
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210093, China
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24
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Nanostructured hollow spheres of hydroxyapatite: preparation and potential application in drug delivery. Front Chem Sci Eng 2012. [DOI: 10.1007/s11705-012-1299-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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25
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Zhang J, Loong WLC, Chou S, Tang C, Wang R, Fane AG. Membrane biofouling and scaling in forward osmosis membrane bioreactor. J Memb Sci 2012. [DOI: 10.1016/j.memsci.2012.01.032] [Citation(s) in RCA: 173] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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26
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Joss A, Baenninger C, Foa P, Koepke S, Krauss M, McArdell CS, Rottermann K, Wei Y, Zapata A, Siegrist H. Water reuse: >90% water yield in MBR/RO through concentrate recycling and CO2 addition as scaling control. WATER RESEARCH 2011; 45:6141-6151. [PMID: 21959090 DOI: 10.1016/j.watres.2011.09.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Revised: 09/04/2011] [Accepted: 09/05/2011] [Indexed: 05/31/2023]
Abstract
Over 1.5 years continuous piloting of a municipal wastewater plant upgraded with a double membrane system (ca. 0.6 m(3) d(-1) of product water produced) have demonstrated the feasibility of achieving high water quality with a water yield of 90% by combining a membrane bioreactor (MBR) with a submerged ultrafiltration membrane followed by a reverse osmosis membrane (RO). The novelty of the proposed treatment scheme consists of the appropriate conditioning of MBR effluent prior to the RO and in recycling the RO concentrates back to the biological unit. All the 15 pharmaceuticals measured in the influent municipal sewage were retained below 100 ng L(-1), a proposed quality parameter, and mostly below detection limits of 10 ng L(-1). The mass balance of the micropollutants shows that these are either degraded or discharged with the excess concentrate, while only minor quantities were found in the excess sludge. The micropollutant load in the concentrate can be significantly reduced by ozonation. A low treated water salinity (<10 mM inorganic salts; 280 ± 70 μS cm(-1)) also confirms that the resulting product has a high water quality. Solids precipitation and inorganic scaling are effectively mitigated by lowering the pH in the RO feed water with CO(2) conditioning, while the concentrate from the RO is recycled to the biological unit where CO(2) is stripped by aeration. This causes precipitation to occur in the bioreactor bulk, where it is much less of a process issue. SiO(2) is the sole exception. Equilibrium modeling of precipitation reactions confirms the effectiveness of this scaling-mitigation approach for CaCO(3) precipitation, calcium phosphate and sulfate minerals.
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Affiliation(s)
- Adriano Joss
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstr. 133, 8600 Duebendorf, Switzerland.
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27
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Contreras AE, Steiner Z, Miao J, Kasher R, Li Q. Studying the role of common membrane surface functionalities on adsorption and cleaning of organic foulants using QCM-D. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:6309-6315. [PMID: 21728383 DOI: 10.1021/es200570t] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Adsorption of organic foulants on nanofiltration (NF) and reverse osmosis (RO) membrane surfaces strongly affects subsequent fouling behavior by modifying the membrane surface. In this study, impact on organic foulant adsorption of specific chemistries including those in commercial thin-film composite membranes was investigated using self-assembled monolayers with seven different ending chemical functionalities (-CH(3), -O-phenyl, -NH(2), ethylene-glycol, -COOH, -CONH(2), and -OH). Adsorption and cleaning of protein (bovine serum albumin) and polysaccharide (sodium alginate) model foulants in two solution conditions were measured using quartz crystal microbalance with dissipation monitoring, and were found to strongly depend on surface functionality. Alginate adsorption correlated with surface hydrophobicity as measured by water contact angle in air; however, adsorption of BSA on hydrophilic -COOH, -NH(2), and -CONH(2) surfaces was high and dominated by hydrogen bond formation and electrostatic attraction. Adsorption of both BSA and alginate was the fastest on -COOH, and adsorption on -NH(2) and -CONH(2) was difficult to remove by surfactant cleaning. BSA adsorption kinetics was shown to be markedly faster than that of alginate, suggesting its importance in the formation of the conditioning layer. Surface modification to render -OH or ethylene-glycol functionalities are expected to reduce membrane fouling.
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Affiliation(s)
- Alison E Contreras
- Department of Civil and Environmental Engineering, Rice University, Houston Texas 77005, United States
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28
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Steiner Z, Miao J, Kasher R. Development of an oligoamide coating as a surface mimetic for aromatic polyamide films used in reverse osmosis membranes. Chem Commun (Camb) 2011; 47:2384-6. [DOI: 10.1039/c0cc04379f] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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