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Johannes S. Vrouwenvelder - One of the best experts on this subject based on the ideXlab platform.

  • Review on strategies for Biofouling mitigation in spiral wound membrane systems
    Desalination, 2018
    Co-Authors: Szilard Bucs, Joop C. Kruithof, Nadia Farhat, Cristian Picioreanu, Mark C.m. Van Loosdrecht, Johannes S. Vrouwenvelder
    Abstract:

    Abstract Because of the uneven distribution of fresh water in time and space, a large number of regions are experiencing water scarcity and stress. Membrane based desalination technologies have the potential to solve the fresh water crisis in coastal areas. However, in many cases membrane performance is restricted by Biofouling. The objective of this review is to provide an overview on the state of the art strategies to control Biofouling in spiral wound reverse osmosis membrane systems and point to possible future research directions. A critical review on Biofouling control strategies such as feed water pre-treatment, membrane surface modification, feed spacer geometry optimization and hydrodynamics in spiral wound membrane systems is presented. In conclusion, Biofouling cannot be avoided in the long run, and thus Biofouling control strategies should focus on delaying the biofilm formation, reducing its impact on membrane performance and enhancing biofilm removal by advanced cleaning strategies. Therefore, future studies should aim on: (i) biofilm structural characterization; (ii) understanding to what extent biofilm properties affect membrane filtration performance, and (iii) developing methods to engineer biofilm properties such that Biofouling would have only a low or delayed impact on the filtration process and accumulated biomass can be easily removed.

  • Early non-destructive Biofouling detection and spatial distribution: Application of oxygen sensing optodes
    Water Research, 2015
    Co-Authors: Nadia Farhat, Marc Staal, Amber Siddiqui, Szilard Bucs, Sergey M. Borisov, Johannes S. Vrouwenvelder
    Abstract:

    Abstract Biofouling is a serious problem in reverse osmosis/nanofiltration (RO/NF) applications, reducing membrane performance. Early detection of Biofouling plays an essential role in an adequate anti-Biofouling strategy. Presently, fouling of membrane filtration systems is mainly determined by measuring changes in pressure drop, which is not exclusively linked to Biofouling. Non-destructive imaging of oxygen concentrations (i) is specific for biological activity of biofilms and (ii) may enable earlier detection of biofilm accumulation than pressure drop. The objective of this study was to test whether transparent luminescent planar O 2 optodes, in combination with a simple imaging system, can be used for early non-destructive Biofouling detection. This Biofouling detection is done by mapping the two-dimensional distribution of O 2 concentrations and O 2 decrease rates inside a membrane fouling simulator (MFS). Results show that at an early stage, Biofouling development was detected by the oxygen sensing optodes while no significant increase in pressure drop was yet observed. Additionally, optodes could detect spatial heterogeneities in Biofouling distribution at a micro scale. Biofilm development started mainly at the feed spacer crossings. The spatial and quantitative information on biological activity will lead to better understanding of the Biofouling processes, contributing to the development of more effective Biofouling control strategies.

  • short term adhesion and long term Biofouling testing of polydopamine and poly ethylene glycol surface modifications of membranes and feed spacers for Biofouling control
    Water Research, 2012
    Co-Authors: Daniel J Miller, Joop C. Kruithof, Paula Araujo, Patricia Correia, Matthew Ramsey, Mark C M Van Loosdrecht, Benny D Freeman, Donald R Paul, Marvin Whiteley, Johannes S. Vrouwenvelder
    Abstract:

    Abstract Ultrafiltration, nanofiltration membranes and feed spacers were hydrophilized with polydopamine and polydopamine- g -poly(ethylene glycol) surface coatings. The fouling propensity of modified and unmodified membranes was evaluated by short-term batch protein and bacterial adhesion tests. The fouling propensity of modified and unmodified membranes and spacers was evaluated by continuous Biofouling experiments in a membrane fouling simulator. The goals of the study were: 1) to determine the effectiveness of polydopamine and polydopamine- g -poly(ethylene glycol) membrane coatings for Biofouling control and 2) to compare techniques commonly used in assessment of membrane Biofouling propensity with Biofouling experiments under practical conditions. Short-term adhesion tests were carried out under static, no-flow conditions for 1 h using bovine serum albumin, a common model globular protein, and Pseudomonas aeruginosa , a common model Gram-negative bacterium. Biofouling tests were performed in a membrane fouling simulator (MFS) for several days under flow conditions similar to those encountered in industrial modules with the autochthonous drinking water population and acetate dosage as organic substrate. Polydopamine- and polydopamine- g -poly(ethylene glycol)-modified membranes showed significantly reduced adhesion of bovine serum albumin and P. aeruginosa in the short-term adhesion tests, but no reduction of Biofouling was observed during longer Biofouling experiments with modified membranes and spacers. These results demonstrate that short-term batch adhesion experiments using model proteins or bacteria under static conditions are not indicative of Biofouling, while continuous Biofouling experiments showed that membrane surface modification by polydopamine and polydopamine- g -poly(ethylene glycol) is not effective for Biofouling control.

  • Biofouling of spiral wound membrane systems
    Water Intelligence Online, 2011
    Co-Authors: Johannes S. Vrouwenvelder, Joop C. Kruithof, Mark C.m. Van Loosdrecht
    Abstract:

    High quality drinking water can be produced with membrane filtration processes like reverse osmosis (RO) and nanofiltration (NF). As the global demand for fresh clean water is increasing, these membrane technologies are increasingly important. One of the most serious problems in RO/NF applications is Biofouling – excessive growth of biomass – affecting the performance of the RO/NF systems. This can be due to the increase in pressure drop across membrane elements (feed-concentrate channel), the decrease in membrane permeability or the increase in salt passage. These phenomena result in the need to increase the feed pressure to maintain constant production and to clean the membrane elements chemically. Biofouling of Spiral Wound Membrane Systems relates biomass accumulation in spiral wound RO and NF membrane elements with membrane performance and hydrodynamics and determines parameters influencing Biofouling. It focuses on the development of biomass in the feed-concentrate (feed-spacer) channel and its effect on pressure drop and flow distribution. It can be used to develop an integral strategy to control Biofouling in spiral wound membrane systems. Most past and present methods to control Biofouling have not been very successful. An overview of several potential complementary approaches to solve Biofouling is given and an integrated approach for Biofouling control is proposed. ISBN: 9781843393634 (Print) ISBN: 9781780400990 (eBook)

  • Biofouling of Spiral Wound Membrane Systems
    2011
    Co-Authors: Johannes S. Vrouwenvelder
    Abstract:

    Biofouling of spiral wound membrane systems High quality drinking water can be produced with membrane filtration processes like reverse osmosis (RO) and nanofiltration (NF). Because the global demand for fresh clean water is increasing, these membrane technologies will increase in importance in the coming decades. One of the most serious problems in RO/NF applications is Biofouling - excessive growth of biomass - affecting the performance of the RO/NF systems due to e.g. (i) increase in pressure drop across membrane elements (feed-concentrate channel), (ii) decrease in membrane permeability, (iii) increase in salt passage. These phenomena result in the need to increase the feed pressure to maintain constant production and to clean the membrane elements chemically. In practice, the first phenomenon is most dominant. The objective of this study was to relate biomass accumulation in spiral wound RO and NF membrane elements with membrane performance and hydrodynamics and to determine parameters influencing Biofouling. The focus of this research was on the development of biomass in the feed-concentrate (feed-spacer) channel and its effect on pressure drop and flow distribution. These detailed studies can be used to develop an integral strategy to control Biofouling in spiral wound membrane systems. Problem analysis Studies to diagnose Biofouling in 15 full-scale RO and NF membrane installations with varying feed water types showed that (i) highest biomass concentrations were found at the installation feed side, (ii) the biomass related parameter adenosine-tri-phosphate was suitable for Biofouling diagnosis in membrane element autopsies, (iii) measurements of biological parameters in the water were not appropriate in quantifying Biofouling, and (iv) there is a need for a representative monitor and sensitive accurate pressure data to enable a reliable evaluation of the development of Biofouling (Chapter 2). Based on the practical observations it was decided to develop a set of tools to study Biofouling at controlled conditions. Method development A monitor was developed (Chapter 3) in combination with testing of a sensitive differential pressure drop transmitter (Chapter 4). This small monitor named Membrane Fouling Simulator (MFS) uses the same membranes and spacers as present in commercial membrane elements, has similar hydrodynamics and is equipped with a sight window. The MFS is an effective scaled-down version of a full-scale system and allows to study the Biofouling process occurring in the first 0.20 m of RO/NF elements. Magnetic Resonance Imaging (MRI) provided in-situ, non-invasive, and spatially-resolved measurements of Biofouling and its impact on hydrodynamics and mass transport in spiral wound membrane elements as well as in the MFS (Chapter 5). A three-dimensional computational model was developed to simulate Biofouling in membrane elements, with feed spacer geometry as used in practice (Chapter 6). The model combines fluid dynamics, solute transport and Biofouling. The methods described in the first part of the thesis have been used to increase the understanding of fundamental aspects of Biofouling. Basic studies The development of biomass and related increase in pressure drop was not influenced by the permeate production in the elements (Chapter 7). Irrespective whether a flux was applied or not, the feed-concentrate channel pressure drop and biofilm amount increased in RO and NF membranes in monitor, test-rig, pilot and full-scale installation. Mass transport calculations supported that permeate production plays a minor role in the development of Biofouling. Since fouling occurred irrespective of permeate production, the critical flux concept stating that “below a critical flux no fouling occurs” is not applicable to control RO/NF Biofouling in extensively pretreated water. In essence, Biofouling is a feed spacer channel problem (Chapter 8). This observation is based on (i) practical data and supported by (ii) in-situ visual observations of fouling accumulation using the MFS sight window, (iii) in-situ non-destructive observations of fouling accumulation and velocity distribution profiles using MRI, and (iv) differences in pressure drop and biomass development in monitors with and without feed spacer. MRI studies showed that already a restricted biofilm accumulation on the feed channel spacer influenced the velocity distribution profile strongly, leading to a strong decrease of the effective surface area in the membrane module and probably increasing the salt concentration in the dead-zones of the element leading to increased salt passage. Three-dimensional numerical simulations of biofilm formation and fluid flow were executed and compared with MRI and MFS studies (Chapter 9). The simulations showed similar (i) pressure drop development and (ii) patterns in flow distribution and channelling as observed in MRI and MFS studies. Feed spacers showed to have an essential role in Biofouling, and are considered a prime target for improving the membrane elements. Based on the gained insights several potential methodologies to minimize the impact of Biofouling have been studied and described in the last chapters of the thesis. Control studies The effect of substrate concentration, linear flow velocity, substrate load and flow direction on pressure drop development and biofilm accumulation was investigated in MFSs (Chapter 10). The pressure drop increase was related to the amount of accumulated biomass and linear flow velocity. Biomass accumulation was related to the substrate load. A flow direction change in the pressure vessels instantaneously reduced the pressure drop, accentuating that hydrodynamics, spacers and pressure vessel configuration offer possibilities to restrict the pressure drop increase caused by accumulated biomass. The impact of flow regime on pressure drop, biomass accumulation and morphology was studied (Chapter 11). In RO and NF membrane elements, at linear flow velocities as applied in practice voluminous and filamentous biofilm structures developed in the feed spacer channel, causing a significant increase in feed channel pressure drop. The amount of accumulated biomass was independent of the applied shear, depending on the substrate load. A high shear force resulted in more compact and less filamentous biofilm structure compared to a low shear force, causing a lower pressure drop increase. A biofilm grown at low shear was easier to remove during water flushing compared to a biofilm grown at high shear. Flow regimes manipulated biofilm morphology affecting membrane performance, enabling new approaches to control Biofouling. Phosphate limitation as a method to control Biofouling was investigated at a full-scale RO installation, characterized by low phosphate and substrate concentrations in the feed water and low biomass amounts in lead membrane modules. MFS studies showed that phosphate limitation restricted the pressure drop increase and biomass accumulation, even in the presence of high substrate concentrations (Chapter 12). Outlook Most past and present methods to control Biofouling have not been very successful. Based on insights obtained by the studies described in this thesis, an overview is given of several potential complementary approaches to solve Biofouling (Chapter 13). An integrated approach for Biofouling control is proposed, based on three corner stones: (i) equipment design and operation, (ii) biomass growth conditions, and (iii) cleaning agents. Although in this stage chemical cleaning and Biofouling inhibitor dosing seem inevitable to control Biofouling, it is expected that in future – also because of sustainability and costs reasons - membrane systems will be operated without or with minimal chemical cleaning and dosing.

Mark C.m. Van Loosdrecht - One of the best experts on this subject based on the ideXlab platform.

  • Review on strategies for Biofouling mitigation in spiral wound membrane systems
    Desalination, 2018
    Co-Authors: Szilard Bucs, Joop C. Kruithof, Nadia Farhat, Cristian Picioreanu, Mark C.m. Van Loosdrecht, Johannes S. Vrouwenvelder
    Abstract:

    Abstract Because of the uneven distribution of fresh water in time and space, a large number of regions are experiencing water scarcity and stress. Membrane based desalination technologies have the potential to solve the fresh water crisis in coastal areas. However, in many cases membrane performance is restricted by Biofouling. The objective of this review is to provide an overview on the state of the art strategies to control Biofouling in spiral wound reverse osmosis membrane systems and point to possible future research directions. A critical review on Biofouling control strategies such as feed water pre-treatment, membrane surface modification, feed spacer geometry optimization and hydrodynamics in spiral wound membrane systems is presented. In conclusion, Biofouling cannot be avoided in the long run, and thus Biofouling control strategies should focus on delaying the biofilm formation, reducing its impact on membrane performance and enhancing biofilm removal by advanced cleaning strategies. Therefore, future studies should aim on: (i) biofilm structural characterization; (ii) understanding to what extent biofilm properties affect membrane filtration performance, and (iii) developing methods to engineer biofilm properties such that Biofouling would have only a low or delayed impact on the filtration process and accumulated biomass can be easily removed.

  • Predicting the impact of feed spacer modification on Biofouling by hydraulic characterization and Biofouling studies in membrane fouling simulators
    Water Research, 2016
    Co-Authors: Amber Siddiqui, M. Fresquet, L. Fel, E.i. Prest, Joelle Ogier, Carsten Schellenberg, Szilard Bucs, S. Lehmann, Mark C.m. Van Loosdrecht, Joop C. Kruithof
    Abstract:

    Abstract Feed spacers are an essential part of spiral-wound reverse osmosis (RO) and nanofiltration (NF) membrane modules. Geometric modification of feed spacers is a potential option to reduce the impact of Biofouling on the performance of membrane systems. The objective of this study was to evaluate the Biofouling potential of two commercially available reference feed spacers and four modified feed spacers. The spacers were compared on hydraulic characterization and in Biofouling studies with membrane fouling simulators (MFSs). The virgin feed spacer was characterized hydraulically by their resistance, measured in terms of feed channel pressure drop, performed by operating MFSs at varying feed water flow rates. Short-term (9 days) Biofouling studies were carried out with nutrient dosage to the MFS feed water to accelerate the Biofouling rate. Long-term (96 days) Biofouling studies were done without nutrient dosage to the MFS feed water. Feed channel pressure drop was monitored and accumulation of active biomass was quantified by adenosine tri phosphate (ATP) determination. The six feed spacers were ranked on pressure drop (hydraulic characterization) and on Biofouling impact (Biofouling studies). Significantly different trends in hydraulic resistance and Biofouling impact for the six feed spacers were observed. The same ranking for Biofouling impact on the feed spacers was found for the (i) short-term Biofouling study with nutrient dosage and the (ii) long-term Biofouling study without nutrient dosage. The ranking for hydraulic resistance for six virgin feed spacers differed significantly from the ranking of the Biofouling impact, indicating that hydraulic resistance of clean feed spacers does not predict the hydraulic resistance of biofouled feed spacers. Better geometric design of feed spacers can be a suitable approach to minimize impact of Biofouling in spiral wound membrane systems.

  • New approaches to characterizing and understanding Biofouling of spiral wound membrane systems
    Water Science and Technology, 2012
    Co-Authors: Mark C.m. Van Loosdrecht, Joop C. Kruithof, Cristian Picioreanu, Ludmilla Bereschenko, A.i. Radu, Michael L. Johns, Hans Vrouwenvelder
    Abstract:

    Historically, Biofouling research on spiral wound membrane systems is typically problem solving oriented. Membrane modules are studied as black box systems, investigated by autopsies. Biofouling is not a simple process. Many factors influence each other in a non-linear fashion. These features make Biofouling a subject which is not easy to study using a fundamental scientific approach. Nevertheless to solve or minimize the negative impacts of Biofouling, a clear understanding of the interacting basic principles is needed. Recent research into microbiological characterizing of Biofouling, small scale test units, application of in situ visualization methods, and model approaches allow such an integrated study of Biofouling.

  • Biofouling of spiral wound membrane systems
    Water Intelligence Online, 2011
    Co-Authors: Johannes S. Vrouwenvelder, Joop C. Kruithof, Mark C.m. Van Loosdrecht
    Abstract:

    High quality drinking water can be produced with membrane filtration processes like reverse osmosis (RO) and nanofiltration (NF). As the global demand for fresh clean water is increasing, these membrane technologies are increasingly important. One of the most serious problems in RO/NF applications is Biofouling – excessive growth of biomass – affecting the performance of the RO/NF systems. This can be due to the increase in pressure drop across membrane elements (feed-concentrate channel), the decrease in membrane permeability or the increase in salt passage. These phenomena result in the need to increase the feed pressure to maintain constant production and to clean the membrane elements chemically. Biofouling of Spiral Wound Membrane Systems relates biomass accumulation in spiral wound RO and NF membrane elements with membrane performance and hydrodynamics and determines parameters influencing Biofouling. It focuses on the development of biomass in the feed-concentrate (feed-spacer) channel and its effect on pressure drop and flow distribution. It can be used to develop an integral strategy to control Biofouling in spiral wound membrane systems. Most past and present methods to control Biofouling have not been very successful. An overview of several potential complementary approaches to solve Biofouling is given and an integrated approach for Biofouling control is proposed. ISBN: 9781843393634 (Print) ISBN: 9781780400990 (eBook)

  • Integrated approach for Biofouling control
    Water Science and Technology, 2010
    Co-Authors: Johannes S. Vrouwenvelder, Joop C. Kruithof, Mark C.m. Van Loosdrecht
    Abstract:

    Despite extensive research efforts, past and present strategies to control Biofouling problems in spiral-wound nanofiltration and reverse osmosis membranes have not been successful under all circumstances. Gaining insight in the Biofouling process is a first necessity. Based on recent insights, an overview is given of 12 potential complementary approaches to solve Biofouling. Combinations of approaches may be more efficient in Biofouling control than a single approach. A single approach must be 100% effective, while in combination each individual approach can be partially effective while the combination is still efficient. An integrated Approach for Biofouling Control (ABC) is proposed, based on three corner stones: (i) equipment design and operation, (ii) biomass growth conditions, and (iii) cleaning agents as a framework to control Biofouling. While past and present strategies addressed mainly membranes and microorganisms, i.e. removal or inactivation of biomass, this ABC-approach addresses the total membrane filtration system. It is anticipated that this integral approach will enable a more rational and effective control of Biofouling. Although in this stage chemical cleaning and Biofouling inhibitor dosage seem unavoidable to control Biofouling, it is expected that in future--because of sustainability and costs reasons--membrane systems will be developed without or with minimal need for chemical cleaning and dosing. Three potential scenarios for Biofouling control are proposed based on (i) Biofouling tolerant spiral wound membrane systems, (ii) capillary membranes, and (iii) phosphate limitation.

Joop C. Kruithof - One of the best experts on this subject based on the ideXlab platform.

  • Review on strategies for Biofouling mitigation in spiral wound membrane systems
    Desalination, 2018
    Co-Authors: Szilard Bucs, Joop C. Kruithof, Nadia Farhat, Cristian Picioreanu, Mark C.m. Van Loosdrecht, Johannes S. Vrouwenvelder
    Abstract:

    Abstract Because of the uneven distribution of fresh water in time and space, a large number of regions are experiencing water scarcity and stress. Membrane based desalination technologies have the potential to solve the fresh water crisis in coastal areas. However, in many cases membrane performance is restricted by Biofouling. The objective of this review is to provide an overview on the state of the art strategies to control Biofouling in spiral wound reverse osmosis membrane systems and point to possible future research directions. A critical review on Biofouling control strategies such as feed water pre-treatment, membrane surface modification, feed spacer geometry optimization and hydrodynamics in spiral wound membrane systems is presented. In conclusion, Biofouling cannot be avoided in the long run, and thus Biofouling control strategies should focus on delaying the biofilm formation, reducing its impact on membrane performance and enhancing biofilm removal by advanced cleaning strategies. Therefore, future studies should aim on: (i) biofilm structural characterization; (ii) understanding to what extent biofilm properties affect membrane filtration performance, and (iii) developing methods to engineer biofilm properties such that Biofouling would have only a low or delayed impact on the filtration process and accumulated biomass can be easily removed.

  • Predicting the impact of feed spacer modification on Biofouling by hydraulic characterization and Biofouling studies in membrane fouling simulators
    Water Research, 2016
    Co-Authors: Amber Siddiqui, M. Fresquet, L. Fel, E.i. Prest, Joelle Ogier, Carsten Schellenberg, Szilard Bucs, S. Lehmann, Mark C.m. Van Loosdrecht, Joop C. Kruithof
    Abstract:

    Abstract Feed spacers are an essential part of spiral-wound reverse osmosis (RO) and nanofiltration (NF) membrane modules. Geometric modification of feed spacers is a potential option to reduce the impact of Biofouling on the performance of membrane systems. The objective of this study was to evaluate the Biofouling potential of two commercially available reference feed spacers and four modified feed spacers. The spacers were compared on hydraulic characterization and in Biofouling studies with membrane fouling simulators (MFSs). The virgin feed spacer was characterized hydraulically by their resistance, measured in terms of feed channel pressure drop, performed by operating MFSs at varying feed water flow rates. Short-term (9 days) Biofouling studies were carried out with nutrient dosage to the MFS feed water to accelerate the Biofouling rate. Long-term (96 days) Biofouling studies were done without nutrient dosage to the MFS feed water. Feed channel pressure drop was monitored and accumulation of active biomass was quantified by adenosine tri phosphate (ATP) determination. The six feed spacers were ranked on pressure drop (hydraulic characterization) and on Biofouling impact (Biofouling studies). Significantly different trends in hydraulic resistance and Biofouling impact for the six feed spacers were observed. The same ranking for Biofouling impact on the feed spacers was found for the (i) short-term Biofouling study with nutrient dosage and the (ii) long-term Biofouling study without nutrient dosage. The ranking for hydraulic resistance for six virgin feed spacers differed significantly from the ranking of the Biofouling impact, indicating that hydraulic resistance of clean feed spacers does not predict the hydraulic resistance of biofouled feed spacers. Better geometric design of feed spacers can be a suitable approach to minimize impact of Biofouling in spiral wound membrane systems.

  • short term adhesion and long term Biofouling testing of polydopamine and poly ethylene glycol surface modifications of membranes and feed spacers for Biofouling control
    Water Research, 2012
    Co-Authors: Daniel J Miller, Joop C. Kruithof, Paula Araujo, Patricia Correia, Matthew Ramsey, Mark C M Van Loosdrecht, Benny D Freeman, Donald R Paul, Marvin Whiteley, Johannes S. Vrouwenvelder
    Abstract:

    Abstract Ultrafiltration, nanofiltration membranes and feed spacers were hydrophilized with polydopamine and polydopamine- g -poly(ethylene glycol) surface coatings. The fouling propensity of modified and unmodified membranes was evaluated by short-term batch protein and bacterial adhesion tests. The fouling propensity of modified and unmodified membranes and spacers was evaluated by continuous Biofouling experiments in a membrane fouling simulator. The goals of the study were: 1) to determine the effectiveness of polydopamine and polydopamine- g -poly(ethylene glycol) membrane coatings for Biofouling control and 2) to compare techniques commonly used in assessment of membrane Biofouling propensity with Biofouling experiments under practical conditions. Short-term adhesion tests were carried out under static, no-flow conditions for 1 h using bovine serum albumin, a common model globular protein, and Pseudomonas aeruginosa , a common model Gram-negative bacterium. Biofouling tests were performed in a membrane fouling simulator (MFS) for several days under flow conditions similar to those encountered in industrial modules with the autochthonous drinking water population and acetate dosage as organic substrate. Polydopamine- and polydopamine- g -poly(ethylene glycol)-modified membranes showed significantly reduced adhesion of bovine serum albumin and P. aeruginosa in the short-term adhesion tests, but no reduction of Biofouling was observed during longer Biofouling experiments with modified membranes and spacers. These results demonstrate that short-term batch adhesion experiments using model proteins or bacteria under static conditions are not indicative of Biofouling, while continuous Biofouling experiments showed that membrane surface modification by polydopamine and polydopamine- g -poly(ethylene glycol) is not effective for Biofouling control.

  • New approaches to characterizing and understanding Biofouling of spiral wound membrane systems
    Water Science and Technology, 2012
    Co-Authors: Mark C.m. Van Loosdrecht, Joop C. Kruithof, Cristian Picioreanu, Ludmilla Bereschenko, A.i. Radu, Michael L. Johns, Hans Vrouwenvelder
    Abstract:

    Historically, Biofouling research on spiral wound membrane systems is typically problem solving oriented. Membrane modules are studied as black box systems, investigated by autopsies. Biofouling is not a simple process. Many factors influence each other in a non-linear fashion. These features make Biofouling a subject which is not easy to study using a fundamental scientific approach. Nevertheless to solve or minimize the negative impacts of Biofouling, a clear understanding of the interacting basic principles is needed. Recent research into microbiological characterizing of Biofouling, small scale test units, application of in situ visualization methods, and model approaches allow such an integrated study of Biofouling.

  • Biofouling of spiral wound membrane systems
    Water Intelligence Online, 2011
    Co-Authors: Johannes S. Vrouwenvelder, Joop C. Kruithof, Mark C.m. Van Loosdrecht
    Abstract:

    High quality drinking water can be produced with membrane filtration processes like reverse osmosis (RO) and nanofiltration (NF). As the global demand for fresh clean water is increasing, these membrane technologies are increasingly important. One of the most serious problems in RO/NF applications is Biofouling – excessive growth of biomass – affecting the performance of the RO/NF systems. This can be due to the increase in pressure drop across membrane elements (feed-concentrate channel), the decrease in membrane permeability or the increase in salt passage. These phenomena result in the need to increase the feed pressure to maintain constant production and to clean the membrane elements chemically. Biofouling of Spiral Wound Membrane Systems relates biomass accumulation in spiral wound RO and NF membrane elements with membrane performance and hydrodynamics and determines parameters influencing Biofouling. It focuses on the development of biomass in the feed-concentrate (feed-spacer) channel and its effect on pressure drop and flow distribution. It can be used to develop an integral strategy to control Biofouling in spiral wound membrane systems. Most past and present methods to control Biofouling have not been very successful. An overview of several potential complementary approaches to solve Biofouling is given and an integrated approach for Biofouling control is proposed. ISBN: 9781843393634 (Print) ISBN: 9781780400990 (eBook)

R. Stanley Williams - One of the best experts on this subject based on the ideXlab platform.

  • Nanomaterials for Biofouling and scaling mitigation of thin film composite membrane: A review
    Desalination, 2016
    Co-Authors: C. S. Ong, W. J. Lau, Antonio C. Torrezan, Min Xian Zhang, Ilan Goldfarb, Peter Eschbach, Ronald D. Kelley, John Paul Strachan, P.s. Goh, Gilberto Medeiros-ribeiro, J. Joshua Yang, Nurasyikin Misdan, Feng Miao, A F Ismail, R. Stanley Williams
    Abstract:

    Biofouling and scaling are commonly encountered bottlenecks in large and small scale installations of membrane technology for surface-, waste- or seawater treatment. The phenomena can pose persistent operational challenge with substantial economic impacts if they are left unresolved. Effort has been made to reduce the tendency of these detrimental phenomena by improving membrane properties, optimizing operational conditions as well as establishing reliable pretreatment of the feed water. This review places a main focus on the recent advances of low Biofouling and scaling thin film composite (TFC) membranes that are incorporated with different types of nanomaterials. In this contribution, the Biofouling and scaling phenomena and their negative effects on TFC membranes are first discussed. The recent studies on the preparation of low Biofouling and anti-scaling TFC membrane using different nanomaterials are then critically summarized. Current challenges to enhance membrane long-term stability, reliability, and cost efficiency are also highlighted. The applications of nanomaterials in membrane desalination are anticipated to improve resistance properties of TFC membranes against Biofouling and scaling and further foster the innovation of sustainable membrane desalination technology.

Talal Yusaf - One of the best experts on this subject based on the ideXlab platform.

  • Biofouling in ro system mechanisms monitoring and controlling
    Desalination, 2012
    Co-Authors: Raed A Aljuboori, Talal Yusaf
    Abstract:

    The reverse osmosis (RO) technology offers a solution for the shortage of pristine water resources worldwide, through its capacity on treating all water kinds such as seawater, wastewater, ground water and surface water. The main concern in using RO technology for water treatment is fouling problems, and in particular Biofouling. Biofouling negatively affects the quality of RO product and renders RO a costly technology for water treatment. The key solution to reduce the risk of Biofouling in RO system lies in understanding the process of Biofouling formation, choosing an adequate biofilm monitoring technique and applying effective Biofouling control treatment for the RO membrane system. In this paper, the mechanisms of microbial adhesion to RO membrane are illustrated along with the key factors that influence the microbial adhesion process. In addition to that, the common strategies for biofilm monitoring in water flow systems are reviewed with highlighting applications, advantages and disadvantages of each strategy. The common Biofouling control methods for reducing the formation of Biofouling in the RO system are also presented in this paper. The application of the environmentally friendly physical disinfection techniques for Biofouling control in the RO membrane system is suggested in this paper.