Pub Date : 2021-07-01DOI: 10.12989/MWT.2021.12.4.157
H. Cha, Y. Park, Kee-Won Seong, K. Park
The electrochemical reduction of nitrate using a divided electrolytic cell in combination with Zn cathode and (Pt)/Ti anode reduced the high concentrations of nitrate (1,000 mg NO3-N/L). A proton exchange membrane (Nafion-117) was used to increase the nitrate reduction efficiency by preventing the re-oxidation of nitrite produced during the reduction process. The current density and anolyte concentration, considered as parameters, were tested to assess the electrochemical reduction of nitrate. The reduction of nitrate shortened the electrolysis time in proportion to the current density, and the time for 90% removal was 5 h at 5 mA/cm2, 3 h at 10 mA/cm2, and 1.8 h at 20 mA/cm2. The yields of ammonia were approximately 50%-55% of the initial nitrate-nitrogen concentration regardless of the current density and was insignificantly related to the anolyte concentration.
{"title":"Electrochemical reduction of nitrate using divided electrolytic cell by proton exchange membrane","authors":"H. Cha, Y. Park, Kee-Won Seong, K. Park","doi":"10.12989/MWT.2021.12.4.157","DOIUrl":"https://doi.org/10.12989/MWT.2021.12.4.157","url":null,"abstract":"The electrochemical reduction of nitrate using a divided electrolytic cell in combination with Zn cathode and (Pt)/Ti anode reduced the high concentrations of nitrate (1,000 mg NO3-N/L). A proton exchange membrane (Nafion-117) was used to increase the nitrate reduction efficiency by preventing the re-oxidation of nitrite produced during the reduction process. The current density and anolyte concentration, considered as parameters, were tested to assess the electrochemical reduction of nitrate. The reduction of nitrate shortened the electrolysis time in proportion to the current density, and the time for 90% removal was 5 h at 5 mA/cm2, 3 h at 10 mA/cm2, and 1.8 h at 20 mA/cm2. The yields of ammonia were approximately 50%-55% of the initial nitrate-nitrogen concentration regardless of the current density and was insignificantly related to the anolyte concentration.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"12 1","pages":"157"},"PeriodicalIF":1.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44702554","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 : 2021-05-01DOI: 10.12989/MWT.2021.12.3.133
D. Das, N. Kayal, M. Innocentini, Daniel G.P. Filho
A water-filtration membrane made of SiC possesses some excellent properties, but its application is limited by high fabrication cost. In this study, two sets of mullite bonded porous SiC ceramics membranes were prepared at reduced temperature by oxidation bonding method using different processing conditions. Dead-end filtration mode was utilized for the determination of permeability and their efficiency towards removal of turbidity. It was found that all the membranes prepared using different composition, pore formers (graphite, PVC and PMMA) and sintering temperature exhibited high turbidity removal efficiency (> 99%). This study provides an efficient method to prepare porous SiC ceramics with excellent permeability and turbidity removal efficiency, which will be helpful for the design of low cost SiC ceramic filters for water treatment.
{"title":"Effect of processing parameters on mullite bonded SiC membrane for turbid water filtration","authors":"D. Das, N. Kayal, M. Innocentini, Daniel G.P. Filho","doi":"10.12989/MWT.2021.12.3.133","DOIUrl":"https://doi.org/10.12989/MWT.2021.12.3.133","url":null,"abstract":"A water-filtration membrane made of SiC possesses some excellent properties, but its application is limited by high fabrication cost. In this study, two sets of mullite bonded porous SiC ceramics membranes were prepared at reduced temperature by oxidation bonding method using different processing conditions. Dead-end filtration mode was utilized for the determination of permeability and their efficiency towards removal of turbidity. It was found that all the membranes prepared using different composition, pore formers (graphite, PVC and PMMA) and sintering temperature exhibited high turbidity removal efficiency (> 99%). This study provides an efficient method to prepare porous SiC ceramics with excellent permeability and turbidity removal efficiency, which will be helpful for the design of low cost SiC ceramic filters for water treatment.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"12 1","pages":"133"},"PeriodicalIF":1.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46311820","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}
The microporous PTFE membrane was used for membrane distillation (MD) experiment and presented ultra-high efficiency of desalination. A hybrid desalination system combining membrane distillation and mechanical vapor compression (MD+MVR) had been developed on the basis of the MD experiment. The system featured that the latent heat and part of sensible heat of vapor from the MVR were recovered to heat the MD process, and the heating process occurred in the same module as the MD process. Models were built according to the energy and mass conservation for the system description. Based on the simulation and experimental data, when the system was assigned a treatment capacity 1000 kg h-1 for 1% saline water and with corresponding 875 kg h-1 fresh water production, it would be stuffed with 75.24 m2 of PTFE membrane and expense only 3.31 kW of electrical power, under 353 K of feed temperature in membrane module and 26 kPa of compressor suction pressure. The compressor power requirement would trade off the heat transfer area with variation of the heat transfer temperature difference. The higher the salinity concentration in the residual concentrate after distillation was, the higher the compressor power, membrane area and heat exchanger area would be.
微孔PTFE膜用于膜蒸馏实验,显示出超高的脱盐效率。在MD实验的基础上,开发了膜蒸馏与机械蒸汽压缩相结合的混合脱盐系统(MD+MVR)。该系统的特点是回收MVR蒸汽的潜热和部分显热来加热MD过程,加热过程与MD过程发生在同一模块中。根据系统描述的能量守恒和质量守恒建立了模型。根据模拟和实验数据,当该系统的处理能力为1000 kg h-1,处理1%的盐水,相应的淡水产量为875 kg h-1时,在膜组件中的进料温度为353 K,压缩机吸入压力为26 kPa的情况下,它将填充75.24 m2的PTFE膜,并且仅消耗3.31 kW的电力。压缩机功率需求将权衡传热面积与传热温差的变化。蒸馏后残余浓缩物中的盐度浓度越高,压缩机功率、膜面积和换热器面积就越大。
{"title":"Hybrid desalination system of mechanical vapor recompression based on membrane distillation","authors":"Yinan Wang, Boya Qiu, Zeyi Xiao, Jingyun Liu, Senqing Fan, X. Tang","doi":"10.12989/MWT.2021.12.3.115","DOIUrl":"https://doi.org/10.12989/MWT.2021.12.3.115","url":null,"abstract":"The microporous PTFE membrane was used for membrane distillation (MD) experiment and presented ultra-high efficiency of desalination. A hybrid desalination system combining membrane distillation and mechanical vapor compression (MD+MVR) had been developed on the basis of the MD experiment. The system featured that the latent heat and part of sensible heat of vapor from the MVR were recovered to heat the MD process, and the heating process occurred in the same module as the MD process. Models were built according to the energy and mass conservation for the system description. Based on the simulation and experimental data, when the system was assigned a treatment capacity 1000 kg h-1 for 1% saline water and with corresponding 875 kg h-1 fresh water production, it would be stuffed with 75.24 m2 of PTFE membrane and expense only 3.31 kW of electrical power, under 353 K of feed temperature in membrane module and 26 kPa of compressor suction pressure. The compressor power requirement would trade off the heat transfer area with variation of the heat transfer temperature difference. The higher the salinity concentration in the residual concentrate after distillation was, the higher the compressor power, membrane area and heat exchanger area would be.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"12 1","pages":"115"},"PeriodicalIF":1.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42197417","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 : 2021-05-01DOI: 10.12989/MWT.2021.12.3.107
Jian Li, Yongbin Zhang
The paper presents the multiscale calculation results for the multiscale flow in micro/nano porous filtration membranes where the adsorbed layer effect is involved, by considering the adsorbed layer-fluid interfacial slippage. The analysis consists of the molecular scale analysis for the adsorbed layer flow and the continuum analysis for the intermediate fluid flow. The calculation results are respectively compared with the classical flow theory calculations and those based on the solid layer assumption. The adsorbed layer flow rate is also compared with the flow rate of the intermediate continuum fluid. It is shown that for a strong fluid-pore wall interaction or for a large adsorbed layer-fluid interfacial slippage the adsorbed layer can be treated as a solid layer; otherwise it should be treated as a flowing layer. The large interfacial slippage results in the flow rate through the pore far greater than the classical Hagen-Poiseuille equation calculation; it largely propels the flow of the intermediate continuum fluid and makes the adsorbed layer flow negligible particularly for the medium and strong fluid-pore wall interactions. The increasing fluid-pore wall interaction strength significantly reduces the flow rate through the pore.
{"title":"Multiscale calculation results of the flow behavior in micro/nano porous filtration membrane with the adsorbed layer-fluid interfacial slippage","authors":"Jian Li, Yongbin Zhang","doi":"10.12989/MWT.2021.12.3.107","DOIUrl":"https://doi.org/10.12989/MWT.2021.12.3.107","url":null,"abstract":"The paper presents the multiscale calculation results for the multiscale flow in micro/nano porous filtration membranes where the adsorbed layer effect is involved, by considering the adsorbed layer-fluid interfacial slippage. The analysis consists of the molecular scale analysis for the adsorbed layer flow and the continuum analysis for the intermediate fluid flow. The calculation results are respectively compared with the classical flow theory calculations and those based on the solid layer assumption. The adsorbed layer flow rate is also compared with the flow rate of the intermediate continuum fluid. It is shown that for a strong fluid-pore wall interaction or for a large adsorbed layer-fluid interfacial slippage the adsorbed layer can be treated as a solid layer; otherwise it should be treated as a flowing layer. The large interfacial slippage results in the flow rate through the pore far greater than the classical Hagen-Poiseuille equation calculation; it largely propels the flow of the intermediate continuum fluid and makes the adsorbed layer flow negligible particularly for the medium and strong fluid-pore wall interactions. The increasing fluid-pore wall interaction strength significantly reduces the flow rate through the pore.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"12 1","pages":"107"},"PeriodicalIF":1.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48643861","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 : 2021-05-01DOI: 10.12989/MWT.2021.12.3.125
F. Heydari, S. Osfouri, M. Abbasi, Mohammad Javad Dianat, J. Khodaveisi
Household or office wastewater consists of two parts of faecal and non-faecal wastewater. Non-faecal section, which accounts for more than 60% of household wastewater, is known as grey water. Treating this part of sewage and using it in various areas can greatly reduce the consumption of potable water. In this research, three methods of advanced oxidation processes including Fenton, UV/H2O2, and UV/TiO2 were investigated for treatment of two grey water sourced from Shif Island and Persian Gulf University restaurant in Bushehr province of Iran. These grey waters were highly polluted with COD content of 600 mg/L and 1400 mg/L, respectively. The efficiency of each process was determined by measuring the COD removal rate. Results showed that at optimum reaction conditions, the COD removal efficiency of the UV/H2O2 process was the best, compared to the other two processes. The COD removal efficiency of UV/H2O2 process at pH = 3 and H2O2 = 1500 and 750 mg/L for grey water of the Shif Island and Persian Gulf University restaurant were 88% and 90%, respectively. Therefore, the treated gray waters can be reused economically.
{"title":"Treatment of highly polluted grey waters using Fenton, UV/H2O2 and UV/TiO2 processes","authors":"F. Heydari, S. Osfouri, M. Abbasi, Mohammad Javad Dianat, J. Khodaveisi","doi":"10.12989/MWT.2021.12.3.125","DOIUrl":"https://doi.org/10.12989/MWT.2021.12.3.125","url":null,"abstract":"Household or office wastewater consists of two parts of faecal and non-faecal wastewater. Non-faecal section, which accounts for more than 60% of household wastewater, is known as grey water. Treating this part of sewage and using it in various areas can greatly reduce the consumption of potable water. In this research, three methods of advanced oxidation processes including Fenton, UV/H2O2, and UV/TiO2 were investigated for treatment of two grey water sourced from Shif Island and Persian Gulf University restaurant in Bushehr province of Iran. These grey waters were highly polluted with COD content of 600 mg/L and 1400 mg/L, respectively. The efficiency of each process was determined by measuring the COD removal rate. Results showed that at optimum reaction conditions, the COD removal efficiency of the UV/H2O2 process was the best, compared to the other two processes. The COD removal efficiency of UV/H2O2 process at pH = 3 and H2O2 = 1500 and 750 mg/L for grey water of the Shif Island and Persian Gulf University restaurant were 88% and 90%, respectively. Therefore, the treated gray waters can be reused economically.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"12 1","pages":"125"},"PeriodicalIF":1.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46082907","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 : 2021-03-01DOI: 10.12989/MWT.2021.12.2.065
M. Issa, Sven-Uwe Geiben, A. Vogelpohl
{"title":"Reduction of energy demand for UF cross-flow membranesin MBR by sponge ball cleaning","authors":"M. Issa, Sven-Uwe Geiben, A. Vogelpohl","doi":"10.12989/MWT.2021.12.2.065","DOIUrl":"https://doi.org/10.12989/MWT.2021.12.2.065","url":null,"abstract":"","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"12 1","pages":"065"},"PeriodicalIF":1.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49471429","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 : 2021-03-01DOI: 10.12989/MWT.2021.12.2.051
Jae Hong Park, Jae Kwan Lee, Dong-seok Shin
The natural weathered sand of basalt (WSB) has been used for the removal of cadmium from aqueous solution. The influence of various parameters i.e., contact time, pH, weathered sand of basalt dosage, particle size of the weathered sand of basalt, temperature and initial cadmium concentration were analyzed. Cadmium adsorption kinetics was well described by the pseudo second order model. Adsorption equilibrium for cadmium was properly well fitted to Langmuir isotherm model with maximum adsorption capacity 0.50 mg/g. Compared with the other experimental results using various kinds of adsorbents at a low concentration (1.0 mg/L or so) similar to that of this study, the cadmium removal efficiency using weathered sand of basalt was higher. It has been demonstrated that weathered sand of basalt has a available alternative adsorbent for cadmium when its initial concentration is low.
{"title":"Low concentration cadmium removal using weathered sand of basalt","authors":"Jae Hong Park, Jae Kwan Lee, Dong-seok Shin","doi":"10.12989/MWT.2021.12.2.051","DOIUrl":"https://doi.org/10.12989/MWT.2021.12.2.051","url":null,"abstract":"The natural weathered sand of basalt (WSB) has been used for the removal of cadmium from aqueous solution. The influence of various parameters i.e., contact time, pH, weathered sand of basalt dosage, particle size of the weathered sand of basalt, temperature and initial cadmium concentration were analyzed. Cadmium adsorption kinetics was well described by the pseudo second order model. Adsorption equilibrium for cadmium was properly well fitted to Langmuir isotherm model with maximum adsorption capacity 0.50 mg/g. Compared with the other experimental results using various kinds of adsorbents at a low concentration (1.0 mg/L or so) similar to that of this study, the cadmium removal efficiency using weathered sand of basalt was higher. It has been demonstrated that weathered sand of basalt has a available alternative adsorbent for cadmium when its initial concentration is low.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"12 1","pages":"051"},"PeriodicalIF":1.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49052783","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 : 2021-03-01DOI: 10.12989/MWT.2021.12.2.059
D. Qadir, R. Nasir, H. Mukhtar, F. Uddin
The rejection of sodium chloride (NaCl) and calcium chloride (CaCl2) single salt solutions were carried out for commercial nanofiltration NFDK membrane. Results showed that the NFDK membrane had a negative surface charge and had a higher observed rejection of 93.65% for calcium (Ca2+) ion and 78.27% for sodium (Na+) ions. Prediction of rejection for aqueous solutions of both salts was made using Donnan Steric Pore Model based on Extended Nernst-Planck Equation in addition to concentration polarization film theory. A MATLAB program was developed to execute the model calculations. Absolute Average Relative Error (% AARE) was found below 5% for real rejection of the NFDK membrane. This research could be used successfully to assess the membrane characterization parameter using a proposed procedure which can reduce the number of experiments.
{"title":"Performance prediction of flat sheet commercial nanofiltration membrane using Donnan-Steric Pore Model","authors":"D. Qadir, R. Nasir, H. Mukhtar, F. Uddin","doi":"10.12989/MWT.2021.12.2.059","DOIUrl":"https://doi.org/10.12989/MWT.2021.12.2.059","url":null,"abstract":"The rejection of sodium chloride (NaCl) and calcium chloride (CaCl2) single salt solutions were carried out for commercial nanofiltration NFDK membrane. Results showed that the NFDK membrane had a negative surface charge and had a higher observed rejection of 93.65% for calcium (Ca2+) ion and 78.27% for sodium (Na+) ions. Prediction of rejection for aqueous solutions of both salts was made using Donnan Steric Pore Model based on Extended Nernst-Planck Equation in addition to concentration polarization film theory. A MATLAB program was developed to execute the model calculations. Absolute Average Relative Error (% AARE) was found below 5% for real rejection of the NFDK membrane. This research could be used successfully to assess the membrane characterization parameter using a proposed procedure which can reduce the number of experiments.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"12 1","pages":"059"},"PeriodicalIF":1.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42459755","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 : 2021-03-01DOI: 10.12989/MWT.2021.12.2.075
H. Ou, Fuzhong Gong, Yanxia Tang, Yan Luo, Liheng Liu
This study aimed to prepare a W/O nonionic microemulsion system(MEs) consisting of OP-4[polyoxyethylene(4) nonylphenol], OP-7[polyoxyethylene(7) nonylphenol], 1-hexanol, D2EHPA, kerosene and HCl solution and applied to the extraction of La(III) from chloride aqueous solution within the polysulfone hollow fiber contactor (HFC),laboratory-scale experiments were carried out to investigate the recovery of La(III) using as-prepared microemulsion from the simulation wastewater containing La(III),Al(III) and Fe(III). The right weight ratio(Rs) of OP-4 to OP-7 was firstly confirmed through determination of the solubilization capacity of HCl solution(W0,HCl) in microemulsion, the effect of several factors such as the HCl concentration, temperature and effective extraction time on the extraction efficiency of La(III) was discussed. Results showed that the acceptable Rs was 4:6 to prepare the W/O MEs. The extraction yield of La(III) increased with the increasing of HCl concentration, temperature and effective extraction time and reaches to 97.3% while using five-stage modules. The recovery yield of La(III) from simulation La-bearing wastewater was 90.6%.
{"title":"Extraction of La(III) by a nonionic microemulsion containing D2EHPA in hollow fiber contactor","authors":"H. Ou, Fuzhong Gong, Yanxia Tang, Yan Luo, Liheng Liu","doi":"10.12989/MWT.2021.12.2.075","DOIUrl":"https://doi.org/10.12989/MWT.2021.12.2.075","url":null,"abstract":"This study aimed to prepare a W/O nonionic microemulsion system(MEs) consisting of OP-4[polyoxyethylene(4) nonylphenol], OP-7[polyoxyethylene(7) nonylphenol], 1-hexanol, D2EHPA, kerosene and HCl solution and applied to the extraction of La(III) from chloride aqueous solution within the polysulfone hollow fiber contactor (HFC),laboratory-scale experiments were carried out to investigate the recovery of La(III) using as-prepared microemulsion from the simulation wastewater containing La(III),Al(III) and Fe(III). The right weight ratio(Rs) of OP-4 to OP-7 was firstly confirmed through determination of the solubilization capacity of HCl solution(W0,HCl) in microemulsion, the effect of several factors such as the HCl concentration, temperature and effective extraction time on the extraction efficiency of La(III) was discussed. Results showed that the acceptable Rs was 4:6 to prepare the W/O MEs. The extraction yield of La(III) increased with the increasing of HCl concentration, temperature and effective extraction time and reaches to 97.3% while using five-stage modules. The recovery yield of La(III) from simulation La-bearing wastewater was 90.6%.","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"12 1","pages":"075"},"PeriodicalIF":1.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49600486","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 : 2021-03-01DOI: 10.12989/MWT.2021.12.2.083
S. Dubey, M. Agarwal, A. Gupta
In this study, defluoridation efficiency by aluminium sulphate (alum) and polyaluminium chloride (PACl) were compared for recommended Nalgonda dose (100%) and 80 % of this dose in both batch and continuous modes. The residual turbidity was found to be higher in case of alum as compared to PACl with 80 % dose representing lesser efficient settling of suspensions, which primarily comprise alumino-fluoro complexes that result in high residual aluminium in the treated water and this was confirmed by TEM and Zeta analysis. Moreover, the application of PACl also resulted in much lesser addition to the TDS and also required lesser lime for pH compensation due to its lower acidity. Hence this reduced dose was recommended for defluoridation. It was also observed that in case of alum, residual aluminium in treated water was 0.88 mg/L (100% dose) & 0.72 mg/L (80% dose) and in case of PACl, it was 0.52 mg/L(100% dose) & 0.41 mg/L(80% dose). After subsequent microfiltration, residual aluminium was 0.28 & 0.21 mg/L for 100 % & 80 % dose respectively and in case of alum and in case of PACl, it was 0.16 & 0.11 for 100% & 80 % dose respectively, which conform to the Al standards(<0.2 mg/L).
{"title":"Fluoride removal using Alum & PACl in batch & continuous modewith subsequent microfiltration","authors":"S. Dubey, M. Agarwal, A. Gupta","doi":"10.12989/MWT.2021.12.2.083","DOIUrl":"https://doi.org/10.12989/MWT.2021.12.2.083","url":null,"abstract":"In this study, defluoridation efficiency by aluminium sulphate (alum) and polyaluminium chloride (PACl) were compared for recommended Nalgonda dose (100%) and 80 % of this dose in both batch and continuous modes. The residual turbidity was found to be higher in case of alum as compared to PACl with 80 % dose representing lesser efficient settling of suspensions, which primarily comprise alumino-fluoro complexes that result in high residual aluminium in the treated water and this was confirmed by TEM and Zeta analysis. Moreover, the application of PACl also resulted in much lesser addition to the TDS and also required lesser lime for pH compensation due to its lower acidity. Hence this reduced dose was recommended for defluoridation. It was also observed that in case of alum, residual aluminium in treated water was 0.88 mg/L (100% dose) & 0.72 mg/L (80% dose) and in case of PACl, it was 0.52 mg/L(100% dose) & 0.41 mg/L(80% dose). After subsequent microfiltration, residual aluminium was 0.28 & 0.21 mg/L for 100 % & 80 % dose respectively and in case of alum and in case of PACl, it was 0.16 & 0.11 for 100% & 80 % dose respectively, which conform to the Al standards(<0.2 mg/L).","PeriodicalId":18416,"journal":{"name":"Membrane Water Treatment","volume":"12 1","pages":"83"},"PeriodicalIF":1.0,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49380618","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}