Pub Date : 2019-07-01DOI: 10.12989/MWT.2019.10.4.277
S. El-ghzizel, H. Jalté, Hajar Zeggar, M. Zait, S. Belhamidi, F. Tiyal, M. Hafsi, M. Taky, A. Elmidaoui
In 2014, the first demineralization plant, using nanofiltration (NF) membrane coupled with renewable energies was realized at Al Annouar high school of Sidi Taibi, Kenitra, Morocco. This project has revealed difficulties related to the membrane performances loss (pressure increase, flux decline, poor water quality of the produced water and increase of energy consumption), as consequences of membrane fouling. To solve this problem, an autopsy of the membrane was done in order to determine the nature and origin of the fouling. The samples of membrane and fouling were then analyzed by scanning electron microscopy using a scanning electron microscope (SEM) connected with an energy dispersive X-ray (EDX) detection system and X-ray diffractometer (XRD). Moreover, three cleaning solutions (hydrochloric acid, nitric acid and sulfuric acid) were tested and assessed in a single cleaning step to find the suitable one for the fouled membrane to regain its initial permeability and performances. The analysis of the experimental results showed that the fouling layer is mainly composed of calcium carbonate (inorganic fouling). Results showed also that the permeability is improved by the hydrochloric acid cleaning (pH=3) with a cleaning efficiency of 93%. Cleaning efficiency did not exceed 75 % with nitric acid (pH=3) and 40 % with sulfuric acid (pH= 3).
{"title":"Autopsy of Nanofiltration membrane of a decentralized demineralization plant","authors":"S. El-ghzizel, H. Jalté, Hajar Zeggar, M. Zait, S. Belhamidi, F. Tiyal, M. Hafsi, M. Taky, A. Elmidaoui","doi":"10.12989/MWT.2019.10.4.277","DOIUrl":"https://doi.org/10.12989/MWT.2019.10.4.277","url":null,"abstract":"In 2014, the first demineralization plant, using nanofiltration (NF) membrane coupled with renewable energies was realized at Al Annouar high school of Sidi Taibi, Kenitra, Morocco. This project has revealed difficulties related to the membrane performances loss (pressure increase, flux decline, poor water quality of the produced water and increase of energy consumption), as consequences of membrane fouling. To solve this problem, an autopsy of the membrane was done in order to determine the nature and origin of the fouling. The samples of membrane and fouling were then analyzed by scanning electron microscopy using a scanning electron microscope (SEM) connected with an energy dispersive X-ray (EDX) detection system and X-ray diffractometer (XRD). Moreover, three cleaning solutions (hydrochloric acid, nitric acid and sulfuric acid) were tested and assessed in a single cleaning step to find the suitable one for the fouled membrane to regain its initial permeability and performances. The analysis of the experimental results showed that the fouling layer is mainly composed of calcium carbonate (inorganic fouling). Results showed also that the permeability is improved by the hydrochloric acid cleaning (pH=3) with a cleaning efficiency of 93%. Cleaning efficiency did not exceed 75 % with nitric acid (pH=3) and 40 % with sulfuric acid (pH= 3).","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"10 1","pages":"277-286"},"PeriodicalIF":1.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46465947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-01DOI: 10.12989/MWT.2019.10.4.299
Yongxun Jin, Yeseul Choi, K. Song, Soyoun Kim, Chanhyuk Park
Managed aquifer recharge (MAR) systems are gaining interest as an alternative to conventional water resources. However, when the water recovered in MAR systems, dissolved iron and manganese species may easily oxidize and they cause well screen clogging or require abandonment of extraction wells. In this study, both oxic and anoxic conditions were analyzed to verify the feasibility of the membrane filtration performance under various solution chemistries. The fouling mechanisms of the metal ions under anoxic conditions were also investigated by employing synthetic wastewater. The fouled membranes were then further analyzed to verify the major causes of inorganic fouling through SEM and XPS. The newly suggested anoxic process refining existing membrane process is expected to provide more precious information about nanofiltration (NF) membrane fouling, especially for demonstrating the potential advantages to chemical-free drinking water production for indirect potable reuse.
{"title":"Iron and manganese removal in direct anoxic nanofiltration for indirect potable reuse","authors":"Yongxun Jin, Yeseul Choi, K. Song, Soyoun Kim, Chanhyuk Park","doi":"10.12989/MWT.2019.10.4.299","DOIUrl":"https://doi.org/10.12989/MWT.2019.10.4.299","url":null,"abstract":"Managed aquifer recharge (MAR) systems are gaining interest as an alternative to conventional water resources. However, when the water recovered in MAR systems, dissolved iron and manganese species may easily oxidize and they cause well screen clogging or require abandonment of extraction wells. In this study, both oxic and anoxic conditions were analyzed to verify the feasibility of the membrane filtration performance under various solution chemistries. The fouling mechanisms of the metal ions under anoxic conditions were also investigated by employing synthetic wastewater. The fouled membranes were then further analyzed to verify the major causes of inorganic fouling through SEM and XPS. The newly suggested anoxic process refining existing membrane process is expected to provide more precious information about nanofiltration (NF) membrane fouling, especially for demonstrating the potential advantages to chemical-free drinking water production for indirect potable reuse.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"10 1","pages":"299-305"},"PeriodicalIF":1.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44889637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-05-01DOI: 10.12989/MWT.2019.10.3.201
Joohyun Kim, Han S. Kim, S. Bae
In this study, we performed an electrowinning process for effective removal of metals (Cu and Ni) in solution and their recovery as solid forms. A complete removal of Cu and Ni (1,000 mg/L) was observed during four times recycling test, indicating that our electrowinning system can ensure the efficient metal removal with high stability and durability. In addition, we investigated effect of operation parameters (i.e., concentration of boric acid only for Ni, variation of pH, concentration of electrolyte (H2SO4), and cell voltage) on the efficiency of metal removal (Cu and Ni) during the electrowinning. The addition of boric acid significantly enhanced removal efficiency of Ni as the concentration of boric acid increased up to 10 g/L. Compared to negligible pH effect (pH 1, 2, and 4) on the Cu removal, we observed the increase in removal efficiency of Ni as the pH increased from 1 to 4. The electrolyte concentration did not significantly influence the removal of Cu and Ni in this study. We also obtained great removal rates of Cu and Ni at 2.5 V and 4.0 V, which were much faster than those at lower voltages. Finally, almost 99% of each Cu and Ni (1,000 mg/L) was selectively removed from the mixture of metals by adjusting pH and addition of boric acid after the completion of Cu removal. The findings in this study can provide a fundamental knowledge about effect of important parameters on the efficiency of metal recovery during the electrowinning.
{"title":"Parametric study for enhanced performance of Cu and Ni electrowinning","authors":"Joohyun Kim, Han S. Kim, S. Bae","doi":"10.12989/MWT.2019.10.3.201","DOIUrl":"https://doi.org/10.12989/MWT.2019.10.3.201","url":null,"abstract":"In this study, we performed an electrowinning process for effective removal of metals (Cu and Ni) in solution and their recovery as solid forms. A complete removal of Cu and Ni (1,000 mg/L) was observed during four times recycling test, indicating that our electrowinning system can ensure the efficient metal removal with high stability and durability. In addition, we investigated effect of operation parameters (i.e., concentration of boric acid only for Ni, variation of pH, concentration of electrolyte (H2SO4), and cell voltage) on the efficiency of metal removal (Cu and Ni) during the electrowinning. The addition of boric acid significantly enhanced removal efficiency of Ni as the concentration of boric acid increased up to 10 g/L. Compared to negligible pH effect (pH 1, 2, and 4) on the Cu removal, we observed the increase in removal efficiency of Ni as the pH increased from 1 to 4. The electrolyte concentration did not significantly influence the removal of Cu and Ni in this study. We also obtained great removal rates of Cu and Ni at 2.5 V and 4.0 V, which were much faster than those at lower voltages. Finally, almost 99% of each Cu and Ni (1,000 mg/L) was selectively removed from the mixture of metals by adjusting pH and addition of boric acid after the completion of Cu removal. The findings in this study can provide a fundamental knowledge about effect of important parameters on the efficiency of metal recovery during the electrowinning.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"10 1","pages":"201-206"},"PeriodicalIF":1.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48843414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-05-01DOI: 10.12989/MWT.2019.10.3.191
K. Min, Jongkeun Lee, H. Cha, K. Park
In this study, we investigated the cultivation possibility using Hydrodictyon reticulatum in a continuous raceway pond as a tertiary sewage treatment plant. The cultivation possibility was evaluated by varying the light quantity, wavelength, and hydraulic retention time (HRT). Experimental results showed that the growth rates of algae and the removal efficiencies of nutrients increased as the light quantity increased, and the maximum photosynthetic rate was maintained at 100 umol/m2.s or higher. When wavelength was varied, nutrient removal efficiency and growth rate increased in the following order: green light, red light, white light, and blue light. The nutrient removal efficiencies and algae productivity in HRT 4 d were better than in HRT 8 d. We conclude that if Hydrodictyon reticulatum is cultivated in a raceway pond and used as a tertiary treatment facility in a sewage treatment plant, nutrients can be effectively removed, and production costs can be reduced.
{"title":"Nutrient removal from secondary effluent using filamentous algae in raceway ponds","authors":"K. Min, Jongkeun Lee, H. Cha, K. Park","doi":"10.12989/MWT.2019.10.3.191","DOIUrl":"https://doi.org/10.12989/MWT.2019.10.3.191","url":null,"abstract":"In this study, we investigated the cultivation possibility using Hydrodictyon reticulatum in a continuous raceway pond as a tertiary sewage treatment plant. The cultivation possibility was evaluated by varying the light quantity, wavelength, and hydraulic retention time (HRT). Experimental results showed that the growth rates of algae and the removal efficiencies of nutrients increased as the light quantity increased, and the maximum photosynthetic rate was maintained at 100 umol/m2.s or higher. When wavelength was varied, nutrient removal efficiency and growth rate increased in the following order: green light, red light, white light, and blue light. The nutrient removal efficiencies and algae productivity in HRT 4 d were better than in HRT 8 d. We conclude that if Hydrodictyon reticulatum is cultivated in a raceway pond and used as a tertiary treatment facility in a sewage treatment plant, nutrients can be effectively removed, and production costs can be reduced.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"10 1","pages":"191-199"},"PeriodicalIF":1.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48632655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-05-01DOI: 10.12989/MWT.2019.10.3.245
Hyobin Wi, Hyowon Kim, Sungwon Kang, Y. Hwang
Prussian blue (PB) is well known for its excellent Cs+ ions adsorption capacity. Due to the high dispersibility of PB in aqueous phase, composite materials imbedding PB in supporting materials have been introduced as a solution. However, building PB particles inside porous supporting materials is still difficult, as PB particles are not fully formed and elute out to water. In this study, we suggest layer-by-layer (LBL) assembly to provide better immobilization of PB on supporting materials of poly vinyl alcohol sponge (PVA) and cellulose filter (CF). Three different PB attachment methods, ex-situ/in-situ/LBL assembly, were evaluated using PB leaching test as well as Cs+ adsorption test. Changes of surface functionality and morphology during PB composite preparation protocols were monitored through Fourier transform infrared spectroscopy and scanning electron microscopy. The results indicate that LBL assembly led to better PB attachment on supporting materials, bringing less eluting PB particles in aqueous phase compared to other synthesis methodologies, such as ex-situ and in-situ synthesis. By enhancing the stability of the adsorbent, adsorption capacity of PVA-PB with LBL improved nine times and that of CF-PB improved over 20 times. Therefore, the results suggest that LBL assembly offers a better orientation for growing PB particles on porous supporting materials
{"title":"Prussian blue immobilization on various filter materials through Layer-by-Layer Assembly for effective cesium adsorption","authors":"Hyobin Wi, Hyowon Kim, Sungwon Kang, Y. Hwang","doi":"10.12989/MWT.2019.10.3.245","DOIUrl":"https://doi.org/10.12989/MWT.2019.10.3.245","url":null,"abstract":"Prussian blue (PB) is well known for its excellent Cs+ ions adsorption capacity. Due to the high dispersibility of PB in aqueous phase, composite materials imbedding PB in supporting materials have been introduced as a solution. However, building PB particles inside porous supporting materials is still difficult, as PB particles are not fully formed and elute out to water. In this study, we suggest layer-by-layer (LBL) assembly to provide better immobilization of PB on supporting materials of poly vinyl alcohol sponge (PVA) and cellulose filter (CF). Three different PB attachment methods, ex-situ/in-situ/LBL assembly, were evaluated using PB leaching test as well as Cs+ adsorption test. Changes of surface functionality and morphology during PB composite preparation protocols were monitored through Fourier transform infrared spectroscopy and scanning electron microscopy. The results indicate that LBL assembly led to better PB attachment on supporting materials, bringing less eluting PB particles in aqueous phase compared to other synthesis methodologies, such as ex-situ and in-situ synthesis. By enhancing the stability of the adsorbent, adsorption capacity of PVA-PB with LBL improved nine times and that of CF-PB improved over 20 times. Therefore, the results suggest that LBL assembly offers a better orientation for growing PB particles on porous supporting materials","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"10 1","pages":"245-250"},"PeriodicalIF":1.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42004939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-05-01DOI: 10.12989/MWT.2019.10.3.239
Jae-Ouk Jung, Bora Shin, Jae Woo Lee, K. Park, Se-Yoen Won, Jinwoo Cho
Plating wastewater containing various heavy metals can be produced by several industries. Specifically, we focused on the removal of copper (Cu2+) and nickel (Ni+) ions from the plating wastewater because all these ions are strictly regulated when discharged into watershed in Korea. The application of both nanofiltration (NF) and reverse osmosis (RO) technologies for the treatment of wastewater containing copper and nickel ions to reduce fresh water consumption and environmental degradation was investigated. In this work, the removal of copper (Cu2+) and nickel (Ni+) ions from synthetic water was studied on pilot scale remove by before using two commercial nanofiltration (NF) and reverse osmosis(RO) spiral-wound membrane modules (NE2521-90 and RE2521-FEN by Toray Chemical). The influence of main operating parameters such as feed concentration on the heavy metals rejection and permeate flux of both membranes, was investigated. Synthetic plating wastewater samples containing copper (Cu2+) and nickel (Ni2+) ions at various concentrations(1, 20, 100, 400 mg/L) were prepared and subjected to treatment by NF and RO in the pilot plant. The results showed that NF, RO process, with 98% and 99% removal for copper and nickel, respectively, could achieve high removal efficiency of the heavy metals.
{"title":"Pilot scale membrane separation of plating wastewater by nanofiltration and reverse osmosis","authors":"Jae-Ouk Jung, Bora Shin, Jae Woo Lee, K. Park, Se-Yoen Won, Jinwoo Cho","doi":"10.12989/MWT.2019.10.3.239","DOIUrl":"https://doi.org/10.12989/MWT.2019.10.3.239","url":null,"abstract":"Plating wastewater containing various heavy metals can be produced by several industries. Specifically, we focused on the removal of copper (Cu2+) and nickel (Ni+) ions from the plating wastewater because all these ions are strictly regulated when discharged into watershed in Korea. The application of both nanofiltration (NF) and reverse osmosis (RO) technologies for the treatment of wastewater containing copper and nickel ions to reduce fresh water consumption and environmental degradation was investigated. In this work, the removal of copper (Cu2+) and nickel (Ni+) ions from synthetic water was studied on pilot scale remove by before using two commercial nanofiltration (NF) and reverse osmosis(RO) spiral-wound membrane modules (NE2521-90 and RE2521-FEN by Toray Chemical). The influence of main operating parameters such as feed concentration on the heavy metals rejection and permeate flux of both membranes, was investigated. Synthetic plating wastewater samples containing copper (Cu2+) and nickel (Ni2+) ions at various concentrations(1, 20, 100, 400 mg/L) were prepared and subjected to treatment by NF and RO in the pilot plant. The results showed that NF, RO process, with 98% and 99% removal for copper and nickel, respectively, could achieve high removal efficiency of the heavy metals.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"10 1","pages":"239-244"},"PeriodicalIF":1.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41465675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-04-30DOI: 10.12989/MWT.2019.10.3.207
O. Choi, Minsup Kim, A. Cho, Y. Choi, G. Kim, Dooil Kim, Jae Woo Lee
Non-aqueous solvents (NASs) are generally known to be barely miscible, and reactive with polar compounds, such as water. However, water can interact with some NASs, which can be used as a new means for water recovery from saline water. This study explored the fate of water and salt in NAS, when saline water is mixed with NAS. Three amine solvents were selected as NAS. They had the same molecular formula, but were differentiated by their molecular structures, as follows: 1) NAS 'A' having the hydrophilic group (NH2) at the end of the straight carbon chain, 2) NAS 'B' with symmetrical structure and having the hydrophilic group (NH) at the middle of the straight carbon chain, 3) NAS 'C' having the hydrophilic group (NH2) at the end of the straight carbon chain but possessing a hydrophobic ethyl branch in the middle of the structure. In batch experiments, 0.5 M NaCl water was blended with NASs, and then water and salt content in the NAS were individually measured. Water absorption efficiencies by NAS 'B' and 'C' were 3.8 and 10.7%, respectively. However, salt rejection efficiency was 98.9% and 58.2%, respectively. NAS 'A' exhibited a higher water absorption efficiency of 35.6%, despite a worse salt rejection efficiency of 24.7%. Molecular dynamic (MD) simulation showed the different interactions of water and salts with each NAS. NAS 'A' formed lattice structured clusters, with the hydrophilic group located outside, and captured a large numbers of water molecules, together with salt ions, inside the cluster pockets. NAS 'B' formed a planar-shaped cluster, where only some water molecules, but no salt ions, migrated to the NAS cluster. NAS 'C', with an ethyl group branch, formed a cluster shaped similarly to that of 'B'; however, the boundary surface of the cluster looked higher than that of 'C', due to the branch structure in solvent. The MD simulation was helpful for understanding the experimental results for water absorption and salt rejection, by demonstrating the various interactions between water molecules and the salts, with the different NAS types.
{"title":"Fates of water and salts in non-aqueous solvents for directional solvent extraction desalination: Effects of chemical structures of the solvents","authors":"O. Choi, Minsup Kim, A. Cho, Y. Choi, G. Kim, Dooil Kim, Jae Woo Lee","doi":"10.12989/MWT.2019.10.3.207","DOIUrl":"https://doi.org/10.12989/MWT.2019.10.3.207","url":null,"abstract":"Non-aqueous solvents (NASs) are generally known to be barely miscible, and reactive with polar compounds, such as water. However, water can interact with some NASs, which can be used as a new means for water recovery from saline water. This study explored the fate of water and salt in NAS, when saline water is mixed with NAS. Three amine solvents were selected as NAS. They had the same molecular formula, but were differentiated by their molecular structures, as follows: 1) NAS 'A' having the hydrophilic group (NH2) at the end of the straight carbon chain, 2) NAS 'B' with symmetrical structure and having the hydrophilic group (NH) at the middle of the straight carbon chain, 3) NAS 'C' having the hydrophilic group (NH2) at the end of the straight carbon chain but possessing a hydrophobic ethyl branch in the middle of the structure. In batch experiments, 0.5 M NaCl water was blended with NASs, and then water and salt content in the NAS were individually measured. Water absorption efficiencies by NAS 'B' and 'C' were 3.8 and 10.7%, respectively. However, salt rejection efficiency was 98.9% and 58.2%, respectively. NAS 'A' exhibited a higher water absorption efficiency of 35.6%, despite a worse salt rejection efficiency of 24.7%. Molecular dynamic (MD) simulation showed the different interactions of water and salts with each NAS. NAS 'A' formed lattice structured clusters, with the hydrophilic group located outside, and captured a large numbers of water molecules, together with salt ions, inside the cluster pockets. NAS 'B' formed a planar-shaped cluster, where only some water molecules, but no salt ions, migrated to the NAS cluster. NAS 'C', with an ethyl group branch, formed a cluster shaped similarly to that of 'B'; however, the boundary surface of the cluster looked higher than that of 'C', due to the branch structure in solvent. The MD simulation was helpful for understanding the experimental results for water absorption and salt rejection, by demonstrating the various interactions between water molecules and the salts, with the different NAS types.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"10 1","pages":"207-212"},"PeriodicalIF":1.0,"publicationDate":"2019-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41586513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-03-01DOI: 10.12989/MWT.2019.10.2.113
Dongmei Li, Jinling Liang, Min-Tsan Huang, Jun Huang, Li Feng, Shaoxiu Li, Yongshi Zhan
To investigate surface properties and interception performances of the new modified PVDF membrane coated with Graphene Oxide (GO) and nano-TiO2 (for short the modified membrane) via the interface polymerization method combined with the pumping suction filtration way, filtration experiments of the modified membrane on Humic Acid (HA) were conducted. Results showed that the contact angle (characterizing the hydrophilicity) of the modified membrane decreased from 80.6+/-1.8 degree to 38.6+/-1.2 degree. The F element of PVDF membrane surface decreased from 60.91% to 17.79% after covered with GO and TiO2. O/C element mass ratio has a fivefold increase, the percentage of O element on the modified membrane surface increased from 3.83 wt% to 20.87%. The modified membrane surface was packed with hydrophilic polar groups (like -COOH, -OH, C-O, C=O, N-H) and a functional hydrophilic GO-polyamide-TiO2 composite configuration. This configuration provided a rigid network structure for the firm attachment of GO and TiO2 on the surface of the membrane and for a higher flux as well. The total flux attenuation rate of the modified membrane decreased to 35.6% while 51.2% for the original one. The irreversible attenuation rate has dropped 71%. The static interception amount of HA on the modified membrane was 158.6 mg/m2, a half of that of the original one (295.0 mg/m2). The flux recovery rate was increased by 50%. The interception rate of the modified membrane on HA increased by 12% approximately and its filtration cycle was 2-3 times of that of the original membrane.
{"title":"Surface properties and interception behaviors of GO-TiO 2 modified PVDF hollow fiber membrane","authors":"Dongmei Li, Jinling Liang, Min-Tsan Huang, Jun Huang, Li Feng, Shaoxiu Li, Yongshi Zhan","doi":"10.12989/MWT.2019.10.2.113","DOIUrl":"https://doi.org/10.12989/MWT.2019.10.2.113","url":null,"abstract":"To investigate surface properties and interception performances of the new modified PVDF membrane coated with Graphene Oxide (GO) and nano-TiO2 (for short the modified membrane) via the interface polymerization method combined with the pumping suction filtration way, filtration experiments of the modified membrane on Humic Acid (HA) were conducted. Results showed that the contact angle (characterizing the hydrophilicity) of the modified membrane decreased from 80.6+/-1.8 degree to 38.6+/-1.2 degree. The F element of PVDF membrane surface decreased from 60.91% to 17.79% after covered with GO and TiO2. O/C element mass ratio has a fivefold increase, the percentage of O element on the modified membrane surface increased from 3.83 wt% to 20.87%. The modified membrane surface was packed with hydrophilic polar groups (like -COOH, -OH, C-O, C=O, N-H) and a functional hydrophilic GO-polyamide-TiO2 composite configuration. This configuration provided a rigid network structure for the firm attachment of GO and TiO2 on the surface of the membrane and for a higher flux as well. The total flux attenuation rate of the modified membrane decreased to 35.6% while 51.2% for the original one. The irreversible attenuation rate has dropped 71%. The static interception amount of HA on the modified membrane was 158.6 mg/m2, a half of that of the original one (295.0 mg/m2). The flux recovery rate was increased by 50%. The interception rate of the modified membrane on HA increased by 12% approximately and its filtration cycle was 2-3 times of that of the original membrane.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"10 1","pages":"113-120"},"PeriodicalIF":1.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48622747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-03-01DOI: 10.12989/MWT.2019.10.2.105
Q. Yuan, Youngchul Kim
On the purpose of conform the more stringent government regulation for turbid stormwater from construction sites, the feasibility and availability of synthetic fiber placing after the conventional protection barrier were tested in this study. Initially, comparative work on the filtering performance of fiber media and conventional gravel filter was carried out, 27% higher filtration capacity was obtained under the similar operational conditions. The filter efficiency was about 20 to 52% with a varying filter depth of 5 to 15cm, presuming at extreme storm flow conditions (800-1500 m/day of filtration rates). Fiber filter was found to have a similar filtration prosperity as grain media; namely, the separation efficiency is directly and inversely proportional to filter depth and rate, respectively. The effects of filter aid (polyaluminium chloride) on filter performance was also investigated, it greatly affected the turbidity reduction at the dosage of 2 mg/L. At the time of breakthrough, a simple filter washing was carried out, herein, the solid recovery achieved over than 88% and greatly determined by operational parameters. Based on the operational data, the empirical models aimed for predicting filtration efficiency were established, which can effectively determine the required filter depth and filtration area in field.
{"title":"A laboratory study on synthetic fiber filter for further treatment of turbid stormwater from construction sites","authors":"Q. Yuan, Youngchul Kim","doi":"10.12989/MWT.2019.10.2.105","DOIUrl":"https://doi.org/10.12989/MWT.2019.10.2.105","url":null,"abstract":"On the purpose of conform the more stringent government regulation for turbid stormwater from construction sites, the feasibility and availability of synthetic fiber placing after the conventional protection barrier were tested in this study. Initially, comparative work on the filtering performance of fiber media and conventional gravel filter was carried out, 27% higher filtration capacity was obtained under the similar operational conditions. The filter efficiency was about 20 to 52% with a varying filter depth of 5 to 15cm, presuming at extreme storm flow conditions (800-1500 m/day of filtration rates). Fiber filter was found to have a similar filtration prosperity as grain media; namely, the separation efficiency is directly and inversely proportional to filter depth and rate, respectively. The effects of filter aid (polyaluminium chloride) on filter performance was also investigated, it greatly affected the turbidity reduction at the dosage of 2 mg/L. At the time of breakthrough, a simple filter washing was carried out, herein, the solid recovery achieved over than 88% and greatly determined by operational parameters. Based on the operational data, the empirical models aimed for predicting filtration efficiency were established, which can effectively determine the required filter depth and filtration area in field.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"10 1","pages":"105-112"},"PeriodicalIF":1.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44856611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-03-01DOI: 10.12989/MWT.2019.10.2.139
R. Lafi, W. Mabrouk, A. Hafiane
In this study, the removal of MB from saline solutions was evaluated by two methods by adsorption and electrodialysis; the adsorption of the mixture dye/salt on dried orange peel waste (OPW) was studied in batch method. In this study the biosorption of cationic dye by OPW was investigated as a function of initial solution pH, and initial salt (sodium chloride) concentration. The maximal dye uptake at pH >= 3.6 in the absence and in the presence of salt and the dye uptake diminished considerably in the presence of increasing concentrations of salt up to 8 g/L. The Redlich Peterson and Langmuir were the most suitable adsorption models for describing the biosorption equilibrium data of the dye both individually and in salt containing medium. As well, this work deals with the electrodialysis application to remove the dye. Synthetic solutions were used for the investigation of the main operational factors affecting the treatment performance; such as applied voltage, pH, initial dye concentration and ionic strength. The experimental results for adsorption and electrodialysis confirmed the importance of electrostatic interactions on the dye. The electrodialysis process with standard ion exchange membranes enabled efficient desalination of cationic dye solutions; there are two main factors in fouling: electrostatic interaction between cations of dyes and the fixed charged groups of the CEM, and affinity interactions.
{"title":"Removal of Methylene blue from saline solutions by adsorption and electrodialysis","authors":"R. Lafi, W. Mabrouk, A. Hafiane","doi":"10.12989/MWT.2019.10.2.139","DOIUrl":"https://doi.org/10.12989/MWT.2019.10.2.139","url":null,"abstract":"In this study, the removal of MB from saline solutions was evaluated by two methods by adsorption and electrodialysis; the adsorption of the mixture dye/salt on dried orange peel waste (OPW) was studied in batch method. In this study the biosorption of cationic dye by OPW was investigated as a function of initial solution pH, and initial salt (sodium chloride) concentration. The maximal dye uptake at pH >= 3.6 in the absence and in the presence of salt and the dye uptake diminished considerably in the presence of increasing concentrations of salt up to 8 g/L. The Redlich Peterson and Langmuir were the most suitable adsorption models for describing the biosorption equilibrium data of the dye both individually and in salt containing medium. As well, this work deals with the electrodialysis application to remove the dye. Synthetic solutions were used for the investigation of the main operational factors affecting the treatment performance; such as applied voltage, pH, initial dye concentration and ionic strength. The experimental results for adsorption and electrodialysis confirmed the importance of electrostatic interactions on the dye. The electrodialysis process with standard ion exchange membranes enabled efficient desalination of cationic dye solutions; there are two main factors in fouling: electrostatic interaction between cations of dyes and the fixed charged groups of the CEM, and affinity interactions.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"10 1","pages":"139-148"},"PeriodicalIF":1.0,"publicationDate":"2019-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46776456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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