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J C Van Dijk - One of the best experts on this subject based on the ideXlab platform.
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removal of different fractions of nom foulants during Demineralized Water backwashing
Separation and Purification Technology, 2012Co-Authors: S G J Heijma, J Q J C Verberk, Arne Verliefde, Gary Amy, J C Van DijkAbstract:Abstract The effectiveness of Demineralized Water backwashing on fouling by different fractions of NOM was investigated in this study. Two types of natural surface Water (Schie canal and Biesbosch reservoir) were tested to confirm the improvement of Demineralized Water backwashing on fouling control, and LC-OCD analysis was conducted on Schie canal Water to find out which fraction of NOM was removed with those backwashes. Results derived from natural Waters showed that Demineralized Water backwashing substantially improved UF fouling control. LC-OCD analyses showed both UF permeate and Demineralized Water backwashes were effective on removing part of biopolymers, but Demineralized Water is also effective for humic substances and a limited amount of low molecular weight substances. However, based on the LC-OCD results, even Demineralized Water backwashing is not effective to remove all humic substances and biopolymers rejected on the UF membranes.
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seaWater ultrafiltration fouling control backwashing with Demineralized Water swro permeate
Separation and Purification Technology, 2012Co-Authors: S G J Heijma, J Q J C Verberk, Gary L Amy, J C Van DijkAbstract:Abstract In this study, the effect of Demineralized Water backwashing on fouling control of seaWater ultrafiltration was investigated. SeaWater from Scheveningen beach in The Hague and a desalination plant of Evides Company at Zeeland in the Netherlands was used as feed Water, while Demineralized Water and UF permeate were used as backwash Water for a fouling control efficiency comparison under different fluxes and backwash durations. Furthermore, Demineralized Waters with 5 or 50 mmol/l NaCl were applied for backwashing as well, to check the influence of monovalent cations on UF fouling control. Additionally, SWRO permeate was used for backwashes in long-term experiments to check the possibility of it replacing Demineralized Water. Results show that seaWater UF fouling control is substantially improved by Demineralized Water backwashing. However, due to the high salinity of seaWater, more Water was required to dilute the cation concentration and limit the dispersion effect near the membrane surface than was needed for surface Water. A 2-min Demineralized Water backwash showed better fouling control efficiency than a 1-min backwash. Furthermore, the presence of monovalent cations in the backwash Water deteriorated the fouling control efficiency of the backwash, indicating the existence of a charge screening effect. The Demineralized Water with 5 and 50 mmol/l NaCl both showed a similar fouling control efficiency which is better than the UF permeate backwash. The calcium ions in UF permeate probably deteriorates the fouling control efficiency by maintaining a Ca-bridging effect between the membranes and NOM. SWRO permeate backwashing successfully controls membrane fouling as well.
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fouling control mechanisms of Demineralized Water backwash reduction of charge screening and calcium bridging effects
Water Research, 2011Co-Authors: S G J Heijma, J Q J C Verberk, Gary L Amy, Pierre Le Clech, A J Kemperma, J C Van DijkAbstract:This paper investigates the impact of the ionic environment on the charge of colloidal natural organic matter (NOM) and ultrafiltration (UF) membranes (charge screening effect) and the calcium adsorption/bridging on new and fouled membranes (calcium bridging effect) by measuring the zeta potentials of membranes and colloidal NOM. Fouling experiments were conducted with natural Water to determine whether the reduction of the charge screening effect and/or calcium bridging effect by backwashing with Demineralized Water can explain the observed reduction in fouling. Results show that the charge of both membranes and NOM, as measured by the zeta potential, became more negative at a lower pH and a lower concentration of electrolytes, in particular, divalent electrolytes. In addition, calcium also adsorbed onto the membranes, and consequently bridged colloidal NOM and membranes via binding with functional groups. The charge screening effect could be eliminated by flushing NOM and membranes with Demineralized Water, since a cation-free environment was established. However, only a limited amount of the calcium bridging connection was removed with Demineralized Water backwashes, so the calcium bridging effect mostly could not be eliminated. As Demineralized Water backwash was found to be effective in fouling control, it can be concluded that the reduction of the charge screening is the dominant mechanism for this.
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application of backwashing with Demineralized Water for uf fouling control in uf ro desalination
Water Science & Technology: Water Supply, 2011Co-Authors: S G J Heijma, J C Van DijkAbstract:The effectiveness of Demineralized Water backwash on ultrafiltration (UF) fouling control of seaWater is investigated in this study. Fouling experiments for two different backwashes (UF permeate and Demineralized Water) were conducted at three fluxes: 120, 180 and 240 L/(h m2) to compare their fouling control efficiency on UF membranes. Results show that backwashing with Demineralized Water improved the fouling control of UF membranes. When the UF membranes were backwashed with Demineralized Water, probably because more foulants were flushed away from the UF membrane than UF permeate backwashes, the increase in trans membrane pressure (TMP) for backwashing with Demineralized Water was less than that with UF permeate. Furthermore, the fluxes of experiments also played a role on the fouling control. When the flux was 120 L/(h m2), the difference between two different backwashes was small. However, at the flux of 240 L/(h m2), the TMP for backwashing with UF permeate increased faster than that with Demineralized Water, although the TMP for backwashing with Demineralized Water increased as well.
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a pilot scale study of backwashing ultrafiltration membrane with Demineralized Water
Journal of Water Supply Research and Technology-aqua, 2010Co-Authors: S G J Heijma, J C Van DijkAbstract:This study investigates the effectiveness of different backwash Waters on ultrafiltration (UF) fouling control on a pilot-scale setup. Surface Water and ion exchange (IEX) pretreated surface Water were used as feed Water. Three backwash Waters were tested: Demineralized Water, UF permeate and nanofiltration (NF) permeate. Results show that backwashing with Demineralized Water substantially improves fouling control efficiency. It is supposed that both the reduction of charge screening and Ca-bridging effect cause this improvement on fouling control. Furthermore, backwashing with NF permeate also negatively influences the fouling control efficiency, indicating the impact of monovalent ions in backwash Water on the ultrafiltration fouling. Findings from such a pilot scale setup also show that it is possible to apply backwashing with Demineralized Water on the operation of UF plants.
S G J Heijma - One of the best experts on this subject based on the ideXlab platform.
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removal of different fractions of nom foulants during Demineralized Water backwashing
Separation and Purification Technology, 2012Co-Authors: S G J Heijma, J Q J C Verberk, Arne Verliefde, Gary Amy, J C Van DijkAbstract:Abstract The effectiveness of Demineralized Water backwashing on fouling by different fractions of NOM was investigated in this study. Two types of natural surface Water (Schie canal and Biesbosch reservoir) were tested to confirm the improvement of Demineralized Water backwashing on fouling control, and LC-OCD analysis was conducted on Schie canal Water to find out which fraction of NOM was removed with those backwashes. Results derived from natural Waters showed that Demineralized Water backwashing substantially improved UF fouling control. LC-OCD analyses showed both UF permeate and Demineralized Water backwashes were effective on removing part of biopolymers, but Demineralized Water is also effective for humic substances and a limited amount of low molecular weight substances. However, based on the LC-OCD results, even Demineralized Water backwashing is not effective to remove all humic substances and biopolymers rejected on the UF membranes.
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seaWater ultrafiltration fouling control backwashing with Demineralized Water swro permeate
Separation and Purification Technology, 2012Co-Authors: S G J Heijma, J Q J C Verberk, Gary L Amy, J C Van DijkAbstract:Abstract In this study, the effect of Demineralized Water backwashing on fouling control of seaWater ultrafiltration was investigated. SeaWater from Scheveningen beach in The Hague and a desalination plant of Evides Company at Zeeland in the Netherlands was used as feed Water, while Demineralized Water and UF permeate were used as backwash Water for a fouling control efficiency comparison under different fluxes and backwash durations. Furthermore, Demineralized Waters with 5 or 50 mmol/l NaCl were applied for backwashing as well, to check the influence of monovalent cations on UF fouling control. Additionally, SWRO permeate was used for backwashes in long-term experiments to check the possibility of it replacing Demineralized Water. Results show that seaWater UF fouling control is substantially improved by Demineralized Water backwashing. However, due to the high salinity of seaWater, more Water was required to dilute the cation concentration and limit the dispersion effect near the membrane surface than was needed for surface Water. A 2-min Demineralized Water backwash showed better fouling control efficiency than a 1-min backwash. Furthermore, the presence of monovalent cations in the backwash Water deteriorated the fouling control efficiency of the backwash, indicating the existence of a charge screening effect. The Demineralized Water with 5 and 50 mmol/l NaCl both showed a similar fouling control efficiency which is better than the UF permeate backwash. The calcium ions in UF permeate probably deteriorates the fouling control efficiency by maintaining a Ca-bridging effect between the membranes and NOM. SWRO permeate backwashing successfully controls membrane fouling as well.
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fouling control mechanisms of Demineralized Water backwash reduction of charge screening and calcium bridging effects
Water Research, 2011Co-Authors: S G J Heijma, J Q J C Verberk, Gary L Amy, Pierre Le Clech, A J Kemperma, J C Van DijkAbstract:This paper investigates the impact of the ionic environment on the charge of colloidal natural organic matter (NOM) and ultrafiltration (UF) membranes (charge screening effect) and the calcium adsorption/bridging on new and fouled membranes (calcium bridging effect) by measuring the zeta potentials of membranes and colloidal NOM. Fouling experiments were conducted with natural Water to determine whether the reduction of the charge screening effect and/or calcium bridging effect by backwashing with Demineralized Water can explain the observed reduction in fouling. Results show that the charge of both membranes and NOM, as measured by the zeta potential, became more negative at a lower pH and a lower concentration of electrolytes, in particular, divalent electrolytes. In addition, calcium also adsorbed onto the membranes, and consequently bridged colloidal NOM and membranes via binding with functional groups. The charge screening effect could be eliminated by flushing NOM and membranes with Demineralized Water, since a cation-free environment was established. However, only a limited amount of the calcium bridging connection was removed with Demineralized Water backwashes, so the calcium bridging effect mostly could not be eliminated. As Demineralized Water backwash was found to be effective in fouling control, it can be concluded that the reduction of the charge screening is the dominant mechanism for this.
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application of backwashing with Demineralized Water for uf fouling control in uf ro desalination
Water Science & Technology: Water Supply, 2011Co-Authors: S G J Heijma, J C Van DijkAbstract:The effectiveness of Demineralized Water backwash on ultrafiltration (UF) fouling control of seaWater is investigated in this study. Fouling experiments for two different backwashes (UF permeate and Demineralized Water) were conducted at three fluxes: 120, 180 and 240 L/(h m2) to compare their fouling control efficiency on UF membranes. Results show that backwashing with Demineralized Water improved the fouling control of UF membranes. When the UF membranes were backwashed with Demineralized Water, probably because more foulants were flushed away from the UF membrane than UF permeate backwashes, the increase in trans membrane pressure (TMP) for backwashing with Demineralized Water was less than that with UF permeate. Furthermore, the fluxes of experiments also played a role on the fouling control. When the flux was 120 L/(h m2), the difference between two different backwashes was small. However, at the flux of 240 L/(h m2), the TMP for backwashing with UF permeate increased faster than that with Demineralized Water, although the TMP for backwashing with Demineralized Water increased as well.
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a pilot scale study of backwashing ultrafiltration membrane with Demineralized Water
Journal of Water Supply Research and Technology-aqua, 2010Co-Authors: S G J Heijma, J C Van DijkAbstract:This study investigates the effectiveness of different backwash Waters on ultrafiltration (UF) fouling control on a pilot-scale setup. Surface Water and ion exchange (IEX) pretreated surface Water were used as feed Water. Three backwash Waters were tested: Demineralized Water, UF permeate and nanofiltration (NF) permeate. Results show that backwashing with Demineralized Water substantially improves fouling control efficiency. It is supposed that both the reduction of charge screening and Ca-bridging effect cause this improvement on fouling control. Furthermore, backwashing with NF permeate also negatively influences the fouling control efficiency, indicating the impact of monovalent ions in backwash Water on the ultrafiltration fouling. Findings from such a pilot scale setup also show that it is possible to apply backwashing with Demineralized Water on the operation of UF plants.
Gary L Amy - One of the best experts on this subject based on the ideXlab platform.
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seaWater ultrafiltration fouling control backwashing with Demineralized Water swro permeate
Separation and Purification Technology, 2012Co-Authors: S G J Heijma, J Q J C Verberk, Gary L Amy, J C Van DijkAbstract:Abstract In this study, the effect of Demineralized Water backwashing on fouling control of seaWater ultrafiltration was investigated. SeaWater from Scheveningen beach in The Hague and a desalination plant of Evides Company at Zeeland in the Netherlands was used as feed Water, while Demineralized Water and UF permeate were used as backwash Water for a fouling control efficiency comparison under different fluxes and backwash durations. Furthermore, Demineralized Waters with 5 or 50 mmol/l NaCl were applied for backwashing as well, to check the influence of monovalent cations on UF fouling control. Additionally, SWRO permeate was used for backwashes in long-term experiments to check the possibility of it replacing Demineralized Water. Results show that seaWater UF fouling control is substantially improved by Demineralized Water backwashing. However, due to the high salinity of seaWater, more Water was required to dilute the cation concentration and limit the dispersion effect near the membrane surface than was needed for surface Water. A 2-min Demineralized Water backwash showed better fouling control efficiency than a 1-min backwash. Furthermore, the presence of monovalent cations in the backwash Water deteriorated the fouling control efficiency of the backwash, indicating the existence of a charge screening effect. The Demineralized Water with 5 and 50 mmol/l NaCl both showed a similar fouling control efficiency which is better than the UF permeate backwash. The calcium ions in UF permeate probably deteriorates the fouling control efficiency by maintaining a Ca-bridging effect between the membranes and NOM. SWRO permeate backwashing successfully controls membrane fouling as well.
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fouling control mechanisms of Demineralized Water backwash reduction of charge screening and calcium bridging effects
Water Research, 2011Co-Authors: S G J Heijma, J Q J C Verberk, Gary L Amy, Pierre Le Clech, A J Kemperma, J C Van DijkAbstract:This paper investigates the impact of the ionic environment on the charge of colloidal natural organic matter (NOM) and ultrafiltration (UF) membranes (charge screening effect) and the calcium adsorption/bridging on new and fouled membranes (calcium bridging effect) by measuring the zeta potentials of membranes and colloidal NOM. Fouling experiments were conducted with natural Water to determine whether the reduction of the charge screening effect and/or calcium bridging effect by backwashing with Demineralized Water can explain the observed reduction in fouling. Results show that the charge of both membranes and NOM, as measured by the zeta potential, became more negative at a lower pH and a lower concentration of electrolytes, in particular, divalent electrolytes. In addition, calcium also adsorbed onto the membranes, and consequently bridged colloidal NOM and membranes via binding with functional groups. The charge screening effect could be eliminated by flushing NOM and membranes with Demineralized Water, since a cation-free environment was established. However, only a limited amount of the calcium bridging connection was removed with Demineralized Water backwashes, so the calcium bridging effect mostly could not be eliminated. As Demineralized Water backwash was found to be effective in fouling control, it can be concluded that the reduction of the charge screening is the dominant mechanism for this.
J Q J C Verberk - One of the best experts on this subject based on the ideXlab platform.
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removal of different fractions of nom foulants during Demineralized Water backwashing
Separation and Purification Technology, 2012Co-Authors: S G J Heijma, J Q J C Verberk, Arne Verliefde, Gary Amy, J C Van DijkAbstract:Abstract The effectiveness of Demineralized Water backwashing on fouling by different fractions of NOM was investigated in this study. Two types of natural surface Water (Schie canal and Biesbosch reservoir) were tested to confirm the improvement of Demineralized Water backwashing on fouling control, and LC-OCD analysis was conducted on Schie canal Water to find out which fraction of NOM was removed with those backwashes. Results derived from natural Waters showed that Demineralized Water backwashing substantially improved UF fouling control. LC-OCD analyses showed both UF permeate and Demineralized Water backwashes were effective on removing part of biopolymers, but Demineralized Water is also effective for humic substances and a limited amount of low molecular weight substances. However, based on the LC-OCD results, even Demineralized Water backwashing is not effective to remove all humic substances and biopolymers rejected on the UF membranes.
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seaWater ultrafiltration fouling control backwashing with Demineralized Water swro permeate
Separation and Purification Technology, 2012Co-Authors: S G J Heijma, J Q J C Verberk, Gary L Amy, J C Van DijkAbstract:Abstract In this study, the effect of Demineralized Water backwashing on fouling control of seaWater ultrafiltration was investigated. SeaWater from Scheveningen beach in The Hague and a desalination plant of Evides Company at Zeeland in the Netherlands was used as feed Water, while Demineralized Water and UF permeate were used as backwash Water for a fouling control efficiency comparison under different fluxes and backwash durations. Furthermore, Demineralized Waters with 5 or 50 mmol/l NaCl were applied for backwashing as well, to check the influence of monovalent cations on UF fouling control. Additionally, SWRO permeate was used for backwashes in long-term experiments to check the possibility of it replacing Demineralized Water. Results show that seaWater UF fouling control is substantially improved by Demineralized Water backwashing. However, due to the high salinity of seaWater, more Water was required to dilute the cation concentration and limit the dispersion effect near the membrane surface than was needed for surface Water. A 2-min Demineralized Water backwash showed better fouling control efficiency than a 1-min backwash. Furthermore, the presence of monovalent cations in the backwash Water deteriorated the fouling control efficiency of the backwash, indicating the existence of a charge screening effect. The Demineralized Water with 5 and 50 mmol/l NaCl both showed a similar fouling control efficiency which is better than the UF permeate backwash. The calcium ions in UF permeate probably deteriorates the fouling control efficiency by maintaining a Ca-bridging effect between the membranes and NOM. SWRO permeate backwashing successfully controls membrane fouling as well.
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fouling control mechanisms of Demineralized Water backwash reduction of charge screening and calcium bridging effects
Water Research, 2011Co-Authors: S G J Heijma, J Q J C Verberk, Gary L Amy, Pierre Le Clech, A J Kemperma, J C Van DijkAbstract:This paper investigates the impact of the ionic environment on the charge of colloidal natural organic matter (NOM) and ultrafiltration (UF) membranes (charge screening effect) and the calcium adsorption/bridging on new and fouled membranes (calcium bridging effect) by measuring the zeta potentials of membranes and colloidal NOM. Fouling experiments were conducted with natural Water to determine whether the reduction of the charge screening effect and/or calcium bridging effect by backwashing with Demineralized Water can explain the observed reduction in fouling. Results show that the charge of both membranes and NOM, as measured by the zeta potential, became more negative at a lower pH and a lower concentration of electrolytes, in particular, divalent electrolytes. In addition, calcium also adsorbed onto the membranes, and consequently bridged colloidal NOM and membranes via binding with functional groups. The charge screening effect could be eliminated by flushing NOM and membranes with Demineralized Water, since a cation-free environment was established. However, only a limited amount of the calcium bridging connection was removed with Demineralized Water backwashes, so the calcium bridging effect mostly could not be eliminated. As Demineralized Water backwash was found to be effective in fouling control, it can be concluded that the reduction of the charge screening is the dominant mechanism for this.
A I Zouboulis - One of the best experts on this subject based on the ideXlab platform.
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production of Demineralized Water for use in thermal power stations by advanced treatment of secondary wasteWater effluent
Journal of Environmental Management, 2017Co-Authors: Ioannis A Katsoyiannis, P Gkotsis, Massimo Castellana, Fabricio Cartechini, A I ZouboulisAbstract:Abstract The operation and efficiency of a modern, high-tech industrial full-scale Water treatment plant was investigated in the present study. The treated Water was used for the supply of the boilers, producing steam to feed the steam turbine of the power station. The inlet Water was the effluent of municipal wasteWater treatment plant of the city of Bari (Italy). The treatment stages comprised (1) coagulation, using ferric chloride, (2) lime softening, (3) powdered activated carbon, all dosed in a sedimentation tank. The treated Water was thereafter subjected to dual-media filtration, followed by ultra-filtration (UF). The outlet of UF was subsequently treated by reverse osmosis (RO) and finally by ion exchange (IX). The inlet Water had total organic carbon (TOC) concentration 10–12 mg/L, turbidity 10–15 NTU and conductivity 3500–4500 μS/cm. The final Demineralized Water had TOC less than 0.2 mg/L, turbidity less than 0.1 NTU and conductivity 0.055–0.070 μS/cm. Organic matter fractionation showed that most of the final DOC concentration consisted of low molecular weight neutral compounds, while other compounds such as humic acids or building blocks were completely removed. It is notable that this plant was operating under “Zero Liquid Discharge” conditions, implementing treatment of any generated liquid waste.
