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Martin Jekel - One of the best experts on this subject based on the ideXlab platform.
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correlations of relevant Membrane foulants with uf Membrane Fouling in different waters
Water Research, 2013Co-Authors: Jiayu Tian, Mathias Ernst, Fuyi Cui, Martin JekelAbstract:Correlations between potential Fouling-relevant substances and Membrane Fouling during ultrafiltration (UF) of different waters were investigated, including water samples from Lake Tegel, from a Berlin canal (Landwehrkanal) and from a wastewater treatment plant (WWTP) secondary effluent. The biopolymers quantified with liquid chromatography-organic carbon detection (LC-OCD) showed a remarkable correlation with UF Membrane Fouling for all the three water sources at different seasons. This finding suggests that the biopolymer content in water can be employed as a universal indicator for predicting Membrane Fouling potential in UF processes. The particulate matter in the two surface waters Lake Tegel and Berlin canal, as characterized by suspended solids and turbidity, also exhibited a distinct correlation with UF Membrane Fouling, although its correlation was slightly weaker than that of biopolymers. However, the humic substances, which are generally believed to be major Membrane foulants, did not show any reliable correlation with the UF Membrane Fouling of the different waters. This work may provide useful information for the development of optimized Fouling control strategies for sustainable UF operation.
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Effect of different cations on UF Membrane Fouling by NOM fractions
Chemical Engineering Journal, 2013Co-Authors: Jiayu Tian, Mathias Ernst, Fuyi Cui, Martin JekelAbstract:This study was carried out to investigate the effect of monovalent Na+ and divalent Ca2+ on UF Membrane Fouling behavior of different NOM fractions—humic substances, proteins and polysaccharides, as represented by humic acid (HA), bovine serum albumin (BSA) and dextran (DEX), respectively. The results showed that Na+ was able to reduce the Membrane Fouling by HA and BSA; while Ca2+ increased both the total Fouling resistance and Fouling irreversibility significantly, illustrating the different effect of monovalent and divalent cations on Membrane Fouling by negatively-charged NOM fractions. On the other hand, for the nearly-neutral DEX, both Na+ and Ca2+ exhibited a slight reduction effect on the Membrane Fouling. The effect of Na+ and Ca2+ on UF Membrane Fouling by combination of different NOM fractions (e.g. HA–BSA and HA–DEX) was also examined in comparison with that by HA alone. As for the HA–BSA combination, synergistic Fouling effect was observed in the presence of Na+; however, when Ca2+ was added (no matter with or without Na+), the Fouling by HA–BSA was decreased as compared with HA alone. As for the combination of HA–DEX, no matter Ca2+ was present or not, monovalent Na+ promoted more severe Membrane Fouling for the HA–DEX in comparison with HA alone; only when Ca2+ was added alone, a reduced Fouling was obtained by the HA–DEX. Furthermore, it was also observed that in the combination system, the Fouling irreversibility was generally lower than that of HA alone, maybe due to the BSA and DEX molecules could interfere with the strong interactions of HA-Membrane and HA–HA.
Fangang Meng - One of the best experts on this subject based on the ideXlab platform.
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morphological visualization componential characterization and microbiological identification of Membrane Fouling in Membrane bioreactors mbrs
Journal of Membrane Science, 2010Co-Authors: Fangang Meng, Bao-qiang Liao, Shuang Liang, Hanmin Zhang, Fenglin Yang, Lianfa SongAbstract:So far, Membrane Fouling in Membrane bioreactors (MBRs) is still not fully understood due to the complex nature of Membrane foulants. The challenge to the study of Membrane Fouling behavior and Membrane Fouling mechanisms calls for the use and/or development of novel approaches for clearer understanding of Membrane foulants such as structure and configuration of Fouling layer, physicochemical and biological nature of Membrane foulants, and deposition behavior of microorganisms on Membranes. As such, MBR Fouling can be characterized by the following: (i) visualization of cake morphology, (ii) analysis of chemical composition and, (iii) identification of microbial community structure. The state-of-the-art approaches used for Membrane Fouling study are critically reviewed in this paper. The advantages and limitations of currently used approaches are discussed as well. Lastly, potential approaches that can be applied for the characterization of Membrane Fouling in MBRs in the future are mentioned.
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Membrane Fouling behavior during filtration of sludge supernatant
Environmental Progress, 2007Co-Authors: Fenglin Yang, Fangang Meng, And Hanmin ZhangAbstract:Colloidal particles and soluble matter in sludge supernatant are major Membrane foulants during the operation of Membrane bioreactors in wastewater treatment. The article discusses Membrane Fouling mechanisms during Membrane filtration of sludge supernatant liquor. The influence of supernatant turbidity, transMembrane pressure, and crossflow velocity on Membrane Fouling was systematically investigated. The Membrane Fouling was characterized by Fourier transform infrared spectroscopy technique. The results showed that the high supernatant turbidity could result in severe Membrane Fouling because of the accumulation of colloidal particles and soluble matter on the Membrane surfaces. High transMembrane pressure could lead to a high flux decline rate because of the formation of a dense cake layer. The crossflow velocity just had a slight influence on Membrane Fouling, as it was not larger than 0.12 m/s, However the Membrane Fouling decreased significantly as crossflow velocity increased to 0.24 m/s. The Membrane Fouling mechanisms of these operational conditions, including supernatant turbidity, transMembrane pressure, and crossflow velocity, were different from each other. Membrane Fouling resistance can be predicted using a simple model based on supernatant turbidity, transMembrane pressure, and crossflow velocity. The major components of the foulants were proteins and polysaccharide materials. © 2007 American Institute of Chemical Engineers Environ Prog 26:86–93, 2007
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Membrane Fouling behavior during filtration of sludge supernatant
Environmental Progress, 2007Co-Authors: Fenglin Yang, Fangang Meng, Baoqiang Shi, And Hanmin ZhangAbstract:Colloidal particles and soluble matter in sludge supernatant are major Membrane foulants during the operation of Membrane bioreactors in wastewater treatment. The article discusses Membrane Fouling mechanisms during Membrane filtration of sludge supernatant liquor. The influence of supernatant turbidity, transMembrane pressure, and crossflow velocity on Membrane Fouling was systematically investigated. The Membrane Fouling was characterized by Fourier transform infrared spectroscopy technique. The results showed that the high supernatant turbidity could result in severe Membrane Fouling because of the accumulation of colloidal particles and soluble matter on the Membrane surfaces. High transMembrane pressure could lead to a high flux decline rate because of the formation of a dense cake layer. The crossflow velocity just had a slight influence on Membrane Fouling, as it was not larger than 0.12 m/s, However the Membrane Fouling decreased significantly as crossflow velocity increased to 0.24 m/s. The Membrane Fouling mechanisms of these operational conditions, including supernatant turbidity, transMembrane pressure, and crossflow velocity, were different from each other. Membrane Fouling resistance can be predicted using a simple model based on supernatant turbidity, transMembrane pressure, and crossflow velocity. The major components of the foulants were proteins and polysaccharide materials.
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identification of activated sludge properties affecting Membrane Fouling in submerged Membrane bioreactors
Separation and Purification Technology, 2006Co-Authors: Fangang Meng, Hanmin Zhang, Fenglin Yang, Shoutong Zhang, Yansong Li, Xingwen ZhangAbstract:Abstract This paper examines the influence of activated sludge properties such as the mixed liquid of suspended solids (MLSS) concentration, sludge particle size distribution (PSD), extracellular polymeric substances (EPS), soluble microbial products (SMP), suspended solids in supernatant (SS s ), dynamic viscosity ( μ ), relative hydrophobicity (RH), and zeta potential on Membrane Fouling. Activated sludge samples from different full-scale and lab-scale Membrane bioreactor processes were used to study their impacts on Membrane Fouling. The influence of activated sludge properties on Membrane permeation was identified with statistical methods. The results showed that MLSS concentration had an exponential relationship with Membrane Fouling resistance. The sludge particle size ( r p = −0.730) was correlated inversely to the Membrane Fouling resistance significantly. The total EPS ( r p = 0.898) and protein ( r p = 0.810) had strong positive effect on Membrane Fouling resistance, but carbohydrate ( r p = 0.626) had a moderate correlation with Membrane Fouling resistance due to its low amounts. SMP ( r p = 0.757), SS s ( r p = 0.810), dynamic viscosity ( r p = 0.691), RH ( r p = 0.837), and zeta potential ( r p = −0.881) also had significant influence on Membrane permeability. However, protein ( r p = 0.936), SMP ( r p = 0.725), SS s ( r p = 0.783), dynamic viscosity ( r p = 0.633), RH ( r p = 0.877), and zeta potential ( r p = −0.953) mainly resulted from the change of EPS concentration. These results confirm that MLSS concentration, PSD and EPS were the predominant factors affecting Membrane Fouling during Membrane filtration of sludge suspension. The Membrane Fouling resistance can be predicted using a simple model based on MLSS concentration, PSD and EPS.
Wei Chen - One of the best experts on this subject based on the ideXlab platform.
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Interaction between humic acid and protein in Membrane Fouling process: A spectroscopic insight
Water research, 2018Co-Authors: Yan-fang Guan, Chen Qian, Wei Chen, Bao-cheng Huang, Yun-jie WangAbstract:Membrane Fouling remains a major challenge for applying Membrane technology to water treatment and, therefore, new tools to recognize the key foulants are essential for characterizing and evaluating the Membrane Fouling process. In this work, fluorescence excitation emission matrix coupled with parallel factor framework-clustering analysis was used to investigate the Membrane Fouling during the filtration process of humic acid (HA) and bovine serum albumin (BSA) solution by polyvinylidene fluoride Membrane. Interestingly, the interaction between BSA and HA in the Membrane Fouling process was observed, and was further confirmed by infrared microspectroscopy and two-dimensional correlation spectroscopic analysis. In addition, the HA-induced Membrane Fouling was observed to be initially relieved, but became aggravated when a certain amount of BSA was added. Furthermore, with such an integrated approach, the OH groups in HA and amide bands in BSA were found to be mainly responsible for the Membrane Fouling and the HA-BSA interaction was mainly caused by the encapsulation of BSA with HA. This work develops a new method for probing Membrane Fouling and demonstrates the interaction between Membrane foulants and its roles in Membrane Fouling process. Furthermore, the integrated approach developed in this work has a potential to explore other types of interfacial interactions.
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Molecular Spectroscopic Characterization of Membrane Fouling: A Critical Review
Chem, 2018Co-Authors: Wei Chen, Chen Qian, Kang Gen ZhouAbstract:Summary Membrane technologies have attracted growing interest in the fields of water purification and energy recovery. Membrane Fouling is the bottleneck that limits the wide application of Membrane-based technologies. Exploration of the Fouling mechanism and the chemical composition, structure, and functions of foulants and their changes in the Membrane filtration process is therefore of significant importance. Molecular spectroscopic methods are among the most efficient platform tools for characterizing Membrane Fouling because of their unique advantages, such as chemical identification at the molecular level, high sensitivity, and spatially temporally resolved feasibility. Here, an overview of spectroscopic and microspectroscopic approaches, including UV-vis, fluorescence, infrared, and Raman spectroscopy, for the online detection, identification, visualization, and chemical characterization of Membrane Fouling is provided, and their main advantages as well as limitations in Membrane-Fouling research are analyzed. Furthermore, future possibilities and challenges for the development of molecular spectroscopy for Membrane-Fouling characterization are envisaged in this critical review.
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Membrane Fouling characteristics and mitigation in a coagulation assisted microfiltration process for municipal wastewater pretreatment
Water Research, 2017Co-Authors: Bao-cheng Huang, Yan-fang Guan, Wei ChenAbstract:Maximizing the energy-profitable treatment of municipal wastewater (MW) is of significance to achieve energy-neutral operation for wastewater treatment plant. Direct Membrane filtration technology has been considered as an effective way to separate organic carbon from MW for subsequent anaerobic energy-recovering process, but its application is restrained by severe Membrane Fouling issues. Thus, it is essential to identify the substances in MW that are responsible for Membrane Fouling and find out efficient anti-Fouling methods. In this work, an integrated approach through combining multivariate curve resolution-alternating least squares analysis with infrared attenuated total reflection mapping was adopted to explore the Membrane Fouling process, and three coagulants, i.e., polyacrylamide, Al2(SO4)3 and FeCl3, were individually used to mitigate Membrane Fouling. Results show that the 1-8 μm biopolymer clusters, i.e., humic-like and protein-like substances, were the predominant foulants in MW. In addition, Membrane Fouling caused by proteins was found to be more severe than that by humic substances. Coagulation pretreatment was demonstrated to be effective in mitigating Membrane Fouling. Al2(SO4)3 or FeCl3 had superior anti-Fouling performance comparing to that of polyacrylamide. The dosage of polyacrylamide needs to be optimized according to the actual MW characteristics as its overdose would cause a substantial decline of Membrane flux. These results provide a deep understanding of the Membrane Fouling mechanisms for organic carbon separation from MW and are beneficial for developing efficient and cost-effective Membrane Fouling mitigation strategies.
Fenglin Yang - One of the best experts on this subject based on the ideXlab platform.
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Relationships between mechanically induced hydrodynamics and Membrane Fouling in a novel rotating Membrane bioreactor
Desalination and Water Treatment, 2013Co-Authors: Tao Jiang, Hanmin Zhang, Fenglin Yang, Dawen GaoAbstract:Abstract The influence of mechanically induced hydrodynamics on Membrane Fouling in a novel rotating flat-sheet Membrane bioreactor (RFMBR) with the comparison of a common Membrane bioreactor (CMBR) is analyzed here by the particle image velocimetry (PIV). Obtained results suggest that the fluid velocity has a slight impact on Membrane Fouling. With the increase in fluid velocity, the Membrane Fouling does not necessarily mitigate. In contrast, the variations in turbulence intensity have a great negative correlation with the changes in Membrane Fouling rate for both MBRs, which means that the turbulence induced by fluctuating velocities is helpful for the alleviation of Membrane Fouling. When comparing the Membrane Fouling between RFMBR and CMBR, it can be concluded that the Membrane Fouling rate for RFMBR is much slower compared to CMBR when consuming the same energy, indicating a more outstanding filtration performance of RFMBR.
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morphological visualization componential characterization and microbiological identification of Membrane Fouling in Membrane bioreactors mbrs
Journal of Membrane Science, 2010Co-Authors: Fangang Meng, Bao-qiang Liao, Shuang Liang, Hanmin Zhang, Fenglin Yang, Lianfa SongAbstract:So far, Membrane Fouling in Membrane bioreactors (MBRs) is still not fully understood due to the complex nature of Membrane foulants. The challenge to the study of Membrane Fouling behavior and Membrane Fouling mechanisms calls for the use and/or development of novel approaches for clearer understanding of Membrane foulants such as structure and configuration of Fouling layer, physicochemical and biological nature of Membrane foulants, and deposition behavior of microorganisms on Membranes. As such, MBR Fouling can be characterized by the following: (i) visualization of cake morphology, (ii) analysis of chemical composition and, (iii) identification of microbial community structure. The state-of-the-art approaches used for Membrane Fouling study are critically reviewed in this paper. The advantages and limitations of currently used approaches are discussed as well. Lastly, potential approaches that can be applied for the characterization of Membrane Fouling in MBRs in the future are mentioned.
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Membrane Fouling behavior during filtration of sludge supernatant
Environmental Progress, 2007Co-Authors: Fenglin Yang, Fangang Meng, And Hanmin ZhangAbstract:Colloidal particles and soluble matter in sludge supernatant are major Membrane foulants during the operation of Membrane bioreactors in wastewater treatment. The article discusses Membrane Fouling mechanisms during Membrane filtration of sludge supernatant liquor. The influence of supernatant turbidity, transMembrane pressure, and crossflow velocity on Membrane Fouling was systematically investigated. The Membrane Fouling was characterized by Fourier transform infrared spectroscopy technique. The results showed that the high supernatant turbidity could result in severe Membrane Fouling because of the accumulation of colloidal particles and soluble matter on the Membrane surfaces. High transMembrane pressure could lead to a high flux decline rate because of the formation of a dense cake layer. The crossflow velocity just had a slight influence on Membrane Fouling, as it was not larger than 0.12 m/s, However the Membrane Fouling decreased significantly as crossflow velocity increased to 0.24 m/s. The Membrane Fouling mechanisms of these operational conditions, including supernatant turbidity, transMembrane pressure, and crossflow velocity, were different from each other. Membrane Fouling resistance can be predicted using a simple model based on supernatant turbidity, transMembrane pressure, and crossflow velocity. The major components of the foulants were proteins and polysaccharide materials. © 2007 American Institute of Chemical Engineers Environ Prog 26:86–93, 2007
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Membrane Fouling behavior during filtration of sludge supernatant
Environmental Progress, 2007Co-Authors: Fenglin Yang, Fangang Meng, Baoqiang Shi, And Hanmin ZhangAbstract:Colloidal particles and soluble matter in sludge supernatant are major Membrane foulants during the operation of Membrane bioreactors in wastewater treatment. The article discusses Membrane Fouling mechanisms during Membrane filtration of sludge supernatant liquor. The influence of supernatant turbidity, transMembrane pressure, and crossflow velocity on Membrane Fouling was systematically investigated. The Membrane Fouling was characterized by Fourier transform infrared spectroscopy technique. The results showed that the high supernatant turbidity could result in severe Membrane Fouling because of the accumulation of colloidal particles and soluble matter on the Membrane surfaces. High transMembrane pressure could lead to a high flux decline rate because of the formation of a dense cake layer. The crossflow velocity just had a slight influence on Membrane Fouling, as it was not larger than 0.12 m/s, However the Membrane Fouling decreased significantly as crossflow velocity increased to 0.24 m/s. The Membrane Fouling mechanisms of these operational conditions, including supernatant turbidity, transMembrane pressure, and crossflow velocity, were different from each other. Membrane Fouling resistance can be predicted using a simple model based on supernatant turbidity, transMembrane pressure, and crossflow velocity. The major components of the foulants were proteins and polysaccharide materials.
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identification of activated sludge properties affecting Membrane Fouling in submerged Membrane bioreactors
Separation and Purification Technology, 2006Co-Authors: Fangang Meng, Hanmin Zhang, Fenglin Yang, Shoutong Zhang, Yansong Li, Xingwen ZhangAbstract:Abstract This paper examines the influence of activated sludge properties such as the mixed liquid of suspended solids (MLSS) concentration, sludge particle size distribution (PSD), extracellular polymeric substances (EPS), soluble microbial products (SMP), suspended solids in supernatant (SS s ), dynamic viscosity ( μ ), relative hydrophobicity (RH), and zeta potential on Membrane Fouling. Activated sludge samples from different full-scale and lab-scale Membrane bioreactor processes were used to study their impacts on Membrane Fouling. The influence of activated sludge properties on Membrane permeation was identified with statistical methods. The results showed that MLSS concentration had an exponential relationship with Membrane Fouling resistance. The sludge particle size ( r p = −0.730) was correlated inversely to the Membrane Fouling resistance significantly. The total EPS ( r p = 0.898) and protein ( r p = 0.810) had strong positive effect on Membrane Fouling resistance, but carbohydrate ( r p = 0.626) had a moderate correlation with Membrane Fouling resistance due to its low amounts. SMP ( r p = 0.757), SS s ( r p = 0.810), dynamic viscosity ( r p = 0.691), RH ( r p = 0.837), and zeta potential ( r p = −0.881) also had significant influence on Membrane permeability. However, protein ( r p = 0.936), SMP ( r p = 0.725), SS s ( r p = 0.783), dynamic viscosity ( r p = 0.633), RH ( r p = 0.877), and zeta potential ( r p = −0.953) mainly resulted from the change of EPS concentration. These results confirm that MLSS concentration, PSD and EPS were the predominant factors affecting Membrane Fouling during Membrane filtration of sludge suspension. The Membrane Fouling resistance can be predicted using a simple model based on MLSS concentration, PSD and EPS.
Jiayu Tian - One of the best experts on this subject based on the ideXlab platform.
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correlations of relevant Membrane foulants with uf Membrane Fouling in different waters
Water Research, 2013Co-Authors: Jiayu Tian, Mathias Ernst, Fuyi Cui, Martin JekelAbstract:Correlations between potential Fouling-relevant substances and Membrane Fouling during ultrafiltration (UF) of different waters were investigated, including water samples from Lake Tegel, from a Berlin canal (Landwehrkanal) and from a wastewater treatment plant (WWTP) secondary effluent. The biopolymers quantified with liquid chromatography-organic carbon detection (LC-OCD) showed a remarkable correlation with UF Membrane Fouling for all the three water sources at different seasons. This finding suggests that the biopolymer content in water can be employed as a universal indicator for predicting Membrane Fouling potential in UF processes. The particulate matter in the two surface waters Lake Tegel and Berlin canal, as characterized by suspended solids and turbidity, also exhibited a distinct correlation with UF Membrane Fouling, although its correlation was slightly weaker than that of biopolymers. However, the humic substances, which are generally believed to be major Membrane foulants, did not show any reliable correlation with the UF Membrane Fouling of the different waters. This work may provide useful information for the development of optimized Fouling control strategies for sustainable UF operation.
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Effect of different cations on UF Membrane Fouling by NOM fractions
Chemical Engineering Journal, 2013Co-Authors: Jiayu Tian, Mathias Ernst, Fuyi Cui, Martin JekelAbstract:This study was carried out to investigate the effect of monovalent Na+ and divalent Ca2+ on UF Membrane Fouling behavior of different NOM fractions—humic substances, proteins and polysaccharides, as represented by humic acid (HA), bovine serum albumin (BSA) and dextran (DEX), respectively. The results showed that Na+ was able to reduce the Membrane Fouling by HA and BSA; while Ca2+ increased both the total Fouling resistance and Fouling irreversibility significantly, illustrating the different effect of monovalent and divalent cations on Membrane Fouling by negatively-charged NOM fractions. On the other hand, for the nearly-neutral DEX, both Na+ and Ca2+ exhibited a slight reduction effect on the Membrane Fouling. The effect of Na+ and Ca2+ on UF Membrane Fouling by combination of different NOM fractions (e.g. HA–BSA and HA–DEX) was also examined in comparison with that by HA alone. As for the HA–BSA combination, synergistic Fouling effect was observed in the presence of Na+; however, when Ca2+ was added (no matter with or without Na+), the Fouling by HA–BSA was decreased as compared with HA alone. As for the combination of HA–DEX, no matter Ca2+ was present or not, monovalent Na+ promoted more severe Membrane Fouling for the HA–DEX in comparison with HA alone; only when Ca2+ was added alone, a reduced Fouling was obtained by the HA–DEX. Furthermore, it was also observed that in the combination system, the Fouling irreversibility was generally lower than that of HA alone, maybe due to the BSA and DEX molecules could interfere with the strong interactions of HA-Membrane and HA–HA.