WorldWideScience

Sample records for ultrafiltration uf membrane

  1. Fate of antibiotics in activated sludge followed by ultrafiltration (CAS-UF) and in a membrane bioreactor (MBR).

    Science.gov (United States)

    Sahar, Eyal; Messalem, Rami; Cikurel, Haim; Aharoni, Avi; Brenner, Asher; Godehardt, Manuel; Jekel, Martin; Ernst, Mathias

    2011-10-15

    The fates of several macrolide, sulphonamide, and trimethoprim antibiotics contained in the raw sewage of the Tel-Aviv wastewater treatment plant (WWTP) were investigated after the sewage was treated using either a full-scale conventional activated sludge (CAS) system coupled with a subsequent ultrafiltration (UF) step or a pilot membrane bioreactor (MBR) system. Antibiotics removal in the MBR system, once it achieved stable operation, was 15-42% higher than that of the CAS system. This advantage was reduced to a maximum of 20% when a UF was added to the CAS. It was hypothesized that the contribution of membrane separation (in both systems) to antibiotics removal was due either to sorption to biomass (rather than improvement in biodegradation) or to enmeshment in the membrane biofilm (since UF membrane pores are significantly larger than the contaminant molecules). Batch experiments with MBR biomass showed a markedly high potential for sorption of the tested antibiotics onto the biomass. Moreover, methanol extraction of MBR biomass released significant amounts of sorbed antibiotics. This finding implies that more attention must be devoted to the management of excess sludge. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Treatment of poultry slaughterhouse wastewater using a static granular bed reactor (SGBR) coupled with ultrafiltration (UF) membrane system.

    Science.gov (United States)

    Basitere, M; Rinquest, Z; Njoya, M; Sheldon, M S; Ntwampe, S K O

    2017-07-01

    The South African poultry industry has grown exponentially in recent years due to an increased demand for their products. As a result, poultry plants consume large volumes of high quality water to ensure that hygienically safe poultry products are produced. Furthermore, poultry industries generate high strength wastewater, which can be treated successfully at low cost using anaerobic digesters. In this study, the performance of a bench-scale mesophilic static granular bed reactor (SGBR) containing fully anaerobic granules coupled with an ultrafiltration (UF) membrane system, as a post-treatment system, was investigated. The poultry slaughterhouse wastewater was characterized by a chemical oxygen demand (COD) range between 1,223 and 9,695mg/L, average biological oxygen demand of 2,375mg/L and average fats, oil and grease (FOG) of 554mg/L. The SGBR anaerobic reactor was operated for 9 weeks at different hydraulic retention times (HRTs), i.e. 55 and 40 h, with an average organic loading rate (OLR) of 1.01 and 3.14g COD/L.day. The SGBR results showed an average COD, total suspended solids (TSS) and FOG removal of 93%, 95% and 90% respectively, for both OLR. The UF post-treatment results showed an average of COD, TSS and FOG removal of 64%, 88% and 48%, respectively. The overall COD, TSS and FOG removal of the system (SGBR and UF membrane) was 98%, 99.8%, and 92.4%, respectively. The results of the combined SGBR reactor coupled with the UF membrane showed a potential to ensure environmentally friendly treatment of poultry slaughterhouse wastewater.

  3. Separation Properties of Wastewater Containing O/W Emulsion Using Ceramic Microfiltration/Ultrafiltration (MF/UF Membranes

    Directory of Open Access Journals (Sweden)

    Kanji Matsumoto

    2013-06-01

    Full Text Available Washing systems using water soluble detergent are used in electrical and mechanical industries and the wastewater containing O/W emulsion are discharged from these systems. Membrane filtration has large potential for the efficient separation of O/W emulsion for reuses of treated water and detergent. The separation properties of O/W emulsions by cross-flow microfiltration and ultrafiltration were studied with ceramic MF and UF membranes. The effects of pore size; applied pressure; cross-flow velocity; and detergent concentration on rejection of O/W emulsion and flux were systematically studied. At the condition achieving complete separation of O/W emulsion the pressure-independent flux was observed and this flux behavior was explained by gel-polarization model. The O/W emulsion tended to permeate through the membrane at the conditions of larger pore size; higher emulsion concentration; and higher pressure. The O/W emulsion could permeate the membrane pore structure by destruction or deformation. These results imply the stability of O/W emulsion in the gel-layer formed on membrane surface play an important role in the separation properties. The O/W emulsion was concentrated by batch cross-flow concentration filtration and the flux decline during the concentration filtration was explained by the gel- polarization model.

  4. Separation Properties of Wastewater Containing O/W Emulsion Using Ceramic Microfiltration/Ultrafiltration (MF/UF) Membranes

    Science.gov (United States)

    Nakamura, Kazuho; Matsumoto, Kanji

    2013-01-01

    Washing systems using water soluble detergent are used in electrical and mechanical industries and the wastewater containing O/W emulsion are discharged from these systems. Membrane filtration has large potential for the efficient separation of O/W emulsion for reuses of treated water and detergent. The separation properties of O/W emulsions by cross-flow microfiltration and ultrafiltration were studied with ceramic MF and UF membranes. The effects of pore size; applied pressure; cross-flow velocity; and detergent concentration on rejection of O/W emulsion and flux were systematically studied. At the condition achieving complete separation of O/W emulsion the pressure-independent flux was observed and this flux behavior was explained by gel-polarization model. The O/W emulsion tended to permeate through the membrane at the conditions of larger pore size; higher emulsion concentration; and higher pressure. The O/W emulsion could permeate the membrane pore structure by destruction or deformation. These results imply the stability of O/W emulsion in the gel-layer formed on membrane surface play an important role in the separation properties. The O/W emulsion was concentrated by batch cross-flow concentration filtration and the flux decline during the concentration filtration was explained by the gel- polarization model. PMID:24958621

  5. The feasibility of nanofiltration membrane bioreactor (NF-MBR)+reverse osmosis (RO) process for water reclamation: Comparison with ultrafiltration membrane bioreactor (UF-MBR)+RO process.

    Science.gov (United States)

    Tay, Ming Feng; Liu, Chang; Cornelissen, Emile R; Wu, Bing; Chong, Tzyy Haur

    2018-02-01

    This study examines the feasibility of a novel nanofiltration membrane bioreactor (NF-MBR) followed by reverse osmosis (RO) process for water reclamation at 90% recovery and using an ultrafiltration MBR (UF-MBR)+RO as baseline for comparison. Both MBRs adopted the same external hollow fiber membrane configurations and operating conditions. The collected permeates of the MBRs were subsequently fed to the respective RO systems. The results showed that the NF-MBR (operated at a constant flux of 10 L/m 2 h) achieved superior MBR permeate quality due to enhanced biodegradation and high rejection capacity of the NF membrane, leading to lower RO fouling rates (∼3.3 times) as compared to the UF-MBR. Further analysis indicated that the cake layer fouling that caused the cake-enhanced osmotic pressure (CEOP) effect contributed predominantly to the transmembrane pressure (TMP) increase in the NF-MBR, while irreversible pore fouling was the major reason for UF membrane fouling. Furthermore, it was found that the biopolymers (i.e., organics with MW > 10 kDa) were the main components present in the foulants of the NF/UF membranes and RO membranes. The analysis indicated that the NF-MBR + RO system at recovery of 90% has comparable energy consumption as the UF-MBR + RO system at recovery of 75%. Our findings proved the feasibility of the NF-MBR + RO for water reclamation at a high recovery rate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Membrane Bioreactor (MBR) as Alternative to a Conventional Activated Sludge System Followed by Ultrafiltration (CAS-UF) for the Treatment of Fischer-Tropsch Reaction Water from Gas-to-Liquids Industries

    NARCIS (Netherlands)

    Laurinonyte, Judita; Meulepas, Roel J.W.; Brink, van den Paula; Temmink, Hardy

    2017-01-01

    The potential of a membrane bioreactor (MBR) system to treat Fischer-Tropsch (FT) reaction water from gas-to-liquids (GTL) industries was investigated and compared with the current treatment system: a conventional activated sludge system followed by an ultrafiltration (CAS-UF) unit. The MBR and

  7. Contribution of effluent organic matter (EfOM) to ultrafiltration (UF) membrane fouling: Isolation, characterization, and fouling effect of EfOM fractions

    KAUST Repository

    Zheng, Xing

    2014-11-01

    EfOM has been regarded as a major organic foulant resulting in UF membrane fouling in wastewater reclamation. To investigate fouling potential of different EfOM fractions, the present study isolated EfOM into hydrophobic neutrals (HPO-N), colloids, hydrophobic acids (HPO-A), transphilic neutrals and acids (TPI), and hydrophilics (HPI), and tested their fouling effect in both salt solution and pure water during ultrafiltration (UF). Major functional groups and chemical structure of the isolates were identified using Fourier transform infrared spectroscopy (FT-IR) and solid-state carbon nuclear magnetic resonance (13C NMR) analysis. The influence of the isolation process on the properties of EfOM fractions was minor because the raw and reconstituted secondary effluents were found similar with respect to UV absorbance, molecular size distribution, and fluorescence character. In membrane filtration tests, unified membrane fouling index (UMFI) and hydraulic resistance were used to quantify irreversible fouling potential of different water samples. Results show that under similar DOC level in feed water, colloids present much more irreversible fouling than other fractions. The fouling effect of the isolates is related to their size, chemical properties, and solution chemistry. Further investigations have identified that the interaction between colloids and other fractions also influences the performance of colloids in fouling phenomena. © 2014 Elsevier Ltd.

  8. Removal of uranium and thorium from aqueous solution by ultrafiltration (UF) and PAMAM dendrimer assisted ultrafiltration (DAUF)

    International Nuclear Information System (INIS)

    Ilaiyaraja, P.; Ashish Kumar Singha Deb; Ponraju, D.

    2015-01-01

    Studies on removal of U(VI) and Th(IV) from aqueous solution have been carried out by ultrafiltration (UF) and dendrimer assisted ultrafiltration (DAUF) using regenerated cellulose acetate membrane and PAMAM [poly(amido)amine] dendrimer chelating agent. In UF, the U(VI) and Th(IV) are removed from aqueous solution by adsorption/mass deposition on the membrane at pH > 4. In DAUF, the water soluble PAMAM dendrimer chelating agent effectively concentrates these metal ions in retentate thereby preventing the mass deposition on membrane. At acidic pH (≤3), the binding of metal ions with PAMAM dendrimer is very weak and hence PAMAM can be regenerated and reused. Electronic supplementary material. The online version of this article (doi:10.1007/s10967-014-3462-x) contains supplementary material, which is available to authorized users. (author)

  9. Dynamic coating of mf/uf membranes for fouling mitigation

    KAUST Repository

    Tabatabai, S. Assiyeh Alizadeh; Leiknes, TorOve

    2017-01-01

    A membrane system including an anti-fouling layer and a method of applying an anti-fouling layer to a membrane surface are provided. In an embodiment, the surface is a microfiltration (MF) or an ultrafiltration (UF) membrane surface. The anti

  10. Contribution of effluent organic matter (EfOM) to ultrafiltration (UF) membrane fouling: Isolation, characterization, and fouling effect of EfOM fractions

    KAUST Repository

    Zheng, Xing; Khan, Muhammad; Croue, Jean-Philippe

    2014-01-01

    EfOM has been regarded as a major organic foulant resulting in UF membrane fouling in wastewater reclamation. To investigate fouling potential of different EfOM fractions, the present study isolated EfOM into hydrophobic neutrals (HPO-N), colloids

  11. Impact of Acid Cleaning on the Performance of PVDF UF Membranes in Seawater Reverse Osmosis Pretreatment

    KAUST Repository

    Alsogair, Safiya

    2016-01-01

    required to maintain the characteristics of the membrane. This research was made with the purpose of investigating the effects of acid cleaning during chemically enhanced backwashing (CEB) on the performance of ultrafiltration (UF) membranes in seawater

  12. Modeling the improvement of ultrafiltration membrane mass transfer when using biofiltration pretreatment in surface water applications.

    Science.gov (United States)

    Netcher, Andrea C; Duranceau, Steven J

    2016-03-01

    In surface water treatment, ultrafiltration (UF) membranes are widely used because of their ability to supply safe drinking water. Although UF membranes produce high-quality water, their efficiency is limited by fouling. Improving UF filtrate productivity is economically desirable and has been attempted by incorporating sustainable biofiltration processes as pretreatment to UF with varying success. The availability of models that can be applied to describe the effectiveness of biofiltration on membrane mass transfer are lacking. In this work, UF water productivity was empirically modeled as a function of biofilter feed water quality using either a quadratic or Gaussian relationship. UF membrane mass transfer variability was found to be governed by the dimensionless mass ratio between the alkalinity (ALK) and dissolved organic carbon (DOC). UF membrane productivity was optimized when the biofilter feed water ALK to DOC ratio fell between 10 and 14. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Dynamic coating of mf/uf membranes for fouling mitigation

    KAUST Repository

    Tabatabai, S. Assiyeh Alizadeh

    2017-01-19

    A membrane system including an anti-fouling layer and a method of applying an anti-fouling layer to a membrane surface are provided. In an embodiment, the surface is a microfiltration (MF) or an ultrafiltration (UF) membrane surface. The anti-fouling layer can include a stimuli responsive layer and a dynamic protective layer applied over the stimuli responsive layer that can be a coating on a surface of the membrane. The stimuli responsive polymer layer can act as an adhesive prior to coating with the dynamic protective layer to aid in adhering the dynamic protective layer to the membrane surface. The dynamic protective layer can be formed by suitable nanoparticles that can prevent adhesion of foulants directly to the membrane surface. The stimuli responsive layer can be responsive to physio- chemical stimuli to cause a release of the stimuli responsive layer and the dynamic protective layer including foulants from the membrane.

  14. Effect of membrane hydrophilization on ultrafiltration performance for biomolecules separation

    International Nuclear Information System (INIS)

    Susanto, H.; Roihatin, A.; Aryanti, N.; Anggoro, D.D.; Ulbricht, M.

    2012-01-01

    This paper compares the performance of different hydrophilization methods to prepare low fouling ultrafiltration (UF) membranes. The methods include post-modification with hydrophilic polymer and blending of hydrophilic agent during either conventional or reactive phase separation (PS). The post-modification was done by photograft copolymerization of water-soluble monomer, poly(ethylene glycol) methacrylate (PEGMA), onto a commercial polyethersulfone (PES) UF membrane. Hydrophilization via blend polymer membrane with hydrophilic additive was performed using non-solvent induced phase separation (NIPS). In reactive PS method, the cast membrane was UV-irradiated before coagulation. The resulting membrane characteristic, the performance and hydrophilization stability were systematically compared. The investigated membrane characteristics include surface hydrophilicity (by contact angle /CA/), surface chemistry (by FTIR spectroscopy), and surface morphology (by scanning electron microscopy). The membrane performance was examined by investigation of adsorptive fouling and ultrafiltration using solution of protein or polysaccharide or humic acid. The results suggest that all methods could increase the hydrophilicity of the membrane yielding less fouling. Post-modification decreased CA from 44.8 ± 4.2 o to 37.8 ± 4.2 o to 42.5 ± 4.3 o depending on the degree of grafting (DG). The hydrophilization via polymer blend decreased CA from from 65 deg. to 54 deg. for PEG concentration of 5%. Nevertheless, decreasing hydraulic permeability was observed after post-modification as well as during polymer blend modification. Stability examination showed that there was leaching out of modifier agent from the membrane matrix prepared via conventional PS after 10 days soaking in both water and NaOH. Reactive PS could increase the stability of the modifier agent in membrane matrix. Highlights: ► We compared different methods to prepare low fouling ultrafiltration (UF) membranes.

  15. Effect of membrane hydrophilization on ultrafiltration performance for biomolecules separation

    Energy Technology Data Exchange (ETDEWEB)

    Susanto, H., E-mail: heru.susanto@undip.ac.id [Department of Chemical Engineering, Universitas Diponegoro, Jl. Prof. Sudarto-Tembalang, Semarang (Indonesia); Roihatin, A.; Aryanti, N.; Anggoro, D.D. [Department of Chemical Engineering, Universitas Diponegoro, Jl. Prof. Sudarto-Tembalang, Semarang (Indonesia); Ulbricht, M. [Lehrstuhl fuer Technische Chemie, Universitaet Duisburg-Essen, Germany, Universitaetstr. 5, Essen (Germany)

    2012-10-01

    This paper compares the performance of different hydrophilization methods to prepare low fouling ultrafiltration (UF) membranes. The methods include post-modification with hydrophilic polymer and blending of hydrophilic agent during either conventional or reactive phase separation (PS). The post-modification was done by photograft copolymerization of water-soluble monomer, poly(ethylene glycol) methacrylate (PEGMA), onto a commercial polyethersulfone (PES) UF membrane. Hydrophilization via blend polymer membrane with hydrophilic additive was performed using non-solvent induced phase separation (NIPS). In reactive PS method, the cast membrane was UV-irradiated before coagulation. The resulting membrane characteristic, the performance and hydrophilization stability were systematically compared. The investigated membrane characteristics include surface hydrophilicity (by contact angle /CA/), surface chemistry (by FTIR spectroscopy), and surface morphology (by scanning electron microscopy). The membrane performance was examined by investigation of adsorptive fouling and ultrafiltration using solution of protein or polysaccharide or humic acid. The results suggest that all methods could increase the hydrophilicity of the membrane yielding less fouling. Post-modification decreased CA from 44.8 {+-} 4.2{sup o} to 37.8 {+-} 4.2{sup o} to 42.5 {+-} 4.3{sup o} depending on the degree of grafting (DG). The hydrophilization via polymer blend decreased CA from from 65 deg. to 54 deg. for PEG concentration of 5%. Nevertheless, decreasing hydraulic permeability was observed after post-modification as well as during polymer blend modification. Stability examination showed that there was leaching out of modifier agent from the membrane matrix prepared via conventional PS after 10 days soaking in both water and NaOH. Reactive PS could increase the stability of the modifier agent in membrane matrix. Highlights: Black-Right-Pointing-Pointer We compared different methods to prepare low

  16. Recycling Cellulase from Enzymatic Hydrolyzate of Laser-Pretreated Corn Stover by UF Membrane

    Directory of Open Access Journals (Sweden)

    Shuang-Qi Tian

    2015-09-01

    Full Text Available The ultrafiltration membrane reactor, utilizing a membrane module with a suitable molecular weight alleyway, retains the larger cellulase components. Smaller molecules, such as the fermentable reducing sugars and water, pass through the membrane. The purpose of this work was to investigate the capability of recycling cellulase in the UF membrane. PS30 hollow fiber membrane, an ultrafiltration method using internal pressure, was found to be an ideal membrane separation device, allowing re-use of the enzyme. A Box-Behnken experimental design (BBD established the following optimum pretreatment parameters: operation pressure at 1.73 bar, temperature at 36.38 °C, and a pH of 5.92. Under these conditions, the model predicted a membrane flux yield of 2.3174 L/(m2•h. The rejection rate of the UF membrane was over 95%.

  17. Antifouling Ultrafiltration Membranes via Post-Fabrication Grafting of Biocidal Nanomaterials

    KAUST Repository

    Mauter, Meagan S.; Wang, Yue; Okemgbo, Kaetochi C.; Osuji, Chinedum O.; Giannelis, Emmanuel P.; Elimelech, Menachem

    2011-01-01

    Figure Presented: Ultrafiltration (UF) membranes perform critical pre-treatment functions in advanced water treatment processes. In operational systems, however, biofouling decreases membrane performance and increases the frequency and cost of chemical cleaning. The present work demonstrates a novel technique for covalently or ionically tethering antimicrobial nanoparticles to the surface of UF membranes. Silver nanoparticles (AgNPs) encapsulated in positively charged polyethyleneimine (PEI) were reacted with an oxygen plasma modified polysulfone UF membrane with and without 1-ethyl-3-(3- dimethylaminopropyl) carbodiimide hydrochloride (EDC) present. The nucleophilic primary amines of the PEI react with the electrophilic carboxyl groups on the UF membrane surface to form electrostatic and covalent bonds. The irreversible modification process imparts significant antimicrobial activity to the membrane surface. Post-synthesis functionalization methods, such as the one presented here, maximize the density of nanomaterials at the membrane surface and may provide a more efficient route for fabricating diverse array of reactive nanocomposite membranes. © 2011 American Chemical Society.

  18. Antifouling Ultrafiltration Membranes via Post-Fabrication Grafting of Biocidal Nanomaterials

    KAUST Repository

    Mauter, Meagan S.

    2011-08-24

    Figure Presented: Ultrafiltration (UF) membranes perform critical pre-treatment functions in advanced water treatment processes. In operational systems, however, biofouling decreases membrane performance and increases the frequency and cost of chemical cleaning. The present work demonstrates a novel technique for covalently or ionically tethering antimicrobial nanoparticles to the surface of UF membranes. Silver nanoparticles (AgNPs) encapsulated in positively charged polyethyleneimine (PEI) were reacted with an oxygen plasma modified polysulfone UF membrane with and without 1-ethyl-3-(3- dimethylaminopropyl) carbodiimide hydrochloride (EDC) present. The nucleophilic primary amines of the PEI react with the electrophilic carboxyl groups on the UF membrane surface to form electrostatic and covalent bonds. The irreversible modification process imparts significant antimicrobial activity to the membrane surface. Post-synthesis functionalization methods, such as the one presented here, maximize the density of nanomaterials at the membrane surface and may provide a more efficient route for fabricating diverse array of reactive nanocomposite membranes. © 2011 American Chemical Society.

  19. Research on the experiment of reservoir water treatment applying ultrafiltration membrane technology of different processes.

    Science.gov (United States)

    Zhang, Liyong; Zhang, Penghui; Wang, Meng; Yang, Kai; Liu, Junliang

    2016-09-01

    The processes and effects of coagulation-ultrafiltration (C-UF) and coagulation sedimentation-ultrafiltration (CS-UF) process used in the treatment of Dalangdian Reservoir water were compared. The experiment data indicated that 99% of turbidity removal and basically 100% of microorganism and algae removal were achieved in both C-UF and CS-UF process. The organic removal effect of CS-UF? process was slightly better than C-UF process. However, the organic removal effect under different processes was not obvious due to limitation of ultrafiltration membrane aperture. Polyaluminium chloride was taken as a coagulant in water plant. The aluminum ion removal result revealed that coagulant dosage was effectively saved by using membrane technology during megathermal high algae laden period. Within the range of certain reagent concentration and soaking time, air-water backwashing of every filtration cycle of membrane was conducted to effectively reduce membrane pollution. Besides, maintenance cleaning was conducted every 60 min. whether or not restorative cleaning was conducted depends on the pollution extent. After cleaning, recovery of membrane filtration effect was obvious.

  20. Treatment of car wash wastewater by UF membranes

    Science.gov (United States)

    Istirokhatun, Titik; Destianti, Puti; Hargianintya, Adenira; Oktiawan, Wiharyanto; Susanto, Heru

    2015-12-01

    The existence of car wash service facilitates car owners to remove dirt and grime from their vehicles. However, the dirt washed off vehicles as well as the cleaning materials themselves may be harmful to the environment if they are not properly managed and discharged. Many technologies have been proposed to treat car wash wastewater such as coagulation flocculation, tricking filter and flocculation-flotation. Nevertheless, these technologies have low efficiency to eliminate oil and small organic compounds. Ultrafiltration (UF) membranes were used in this study to treat car wash wastewater. This study investigated the performance of UF membranes under various pressures to remove COD, oil and grease, and also turbidity from car wash waste water. The membrane performance was examined by investigation of permeate flux and membrane rejection. The results meet the standard of environmental regulation and it is possible to be reused. The highest rejection was shown by PES10 (polyethersulfone 10 kDa) in 1 bar operation with complete rejection for both turbidity and oil and grace and 95% rejection for COD.

  1. Characterization of clean and fouled ultrafiltration membranes

    NARCIS (Netherlands)

    Hanemaaijer, J.H.; Robbertsen, T.; van den Boomgaard, Anthonie; Olieman, C.; Both, P.; Schmidt, D.G.

    1988-01-01

    Much research into the fundamentals of membrane formation and separation has been performed in order to improve the efficiency of the manufacture of ultrafiltration membranes. Determination of the membrane characteristics is a key problem in these investigations. In this paper, we report on a study

  2. Tight ceramic UF membrane as RO pre-treatment: The role of electrostatic interactions on phosphate rejection

    NARCIS (Netherlands)

    Shang, R.; Verliefde, A.R.D.; Hu, J.; Zeng, Z; Lu, L.; Lu, L.; Kemperman, Antonius J.B.; Deng, H.; Nijmeijer, Dorothea C.; Heijman, S.G.J.; Rietveld, L.C.

    2014-01-01

    Phosphate limitation has been reported as an effective approach to inhibit biofouling in reverse osmosis (RO) systems for water purification. The rejection of dissolved phosphate by negatively charged TiO2 tight ultrafiltration (UF) membranes (1 kDa and 3 kDa) was observed. These membranes can

  3. Ultrafiltration (UF Pilot Plant for Municipal Wastewater Reuse in Agriculture: Impact of the Operation Mode on Process Performance

    Directory of Open Access Journals (Sweden)

    Dario Falsanisi

    2010-11-01

    Full Text Available Following increasing interest in the use of UltraFiltration (UF membrane processes as an alternative advanced disinfection technique, the performance of a UF pilot plant was investigated under two opposite operating conditions (“stressed operating condition” versus “conventional operating condition”. The results indicate that for both conditions, the reclaimed effluent complied with the Italian regulations for unrestricted wastewater reuse (i.e., Total Suspended Solids (TSS < 10 mg/L; Chemical Oxygen Demand (COD < 100 mg/L and Escherichia coli < 10 CFU/100 mL. On the other hand, when compared with the Title 22 of the California Wastewater Reclamation Criteria, only the effluent produced under the “conventional operating condition” met the stipulated water quality standards (i.e., TSS and turbidity undetectable and total coliforms < 2.2 CFU/100 mL. It should be noted that, in spite of the nominal cut-off size, total coliforms breakthrough was indeed occasionally observed. A localized membrane pore micro-enlargement mechanism was hypothesized to explain the total coliforms propagation in the ultrafiltered effluent, as monitoring of the membrane permeability and transmembrane pressure highlighted that gel/cake formation had only a minor contribution to the overall membrane fouling mechanism with respect to pore plugging and pore narrowing mechanisms.

  4. Removal of paraquat and linuron from water by continuous flow adsorption/ ultrafiltration membrane processes

    International Nuclear Information System (INIS)

    Zahoor, M.

    2013-01-01

    The magnetic activated carbon (MAC) was prepared, characterized and compared with powdered activated carbon (PAC) for its adsorptive parameters. Both adsorbents were then used in combination ultrafiltration (UF) membrane as pretreatment for the removal of paraquat and linuron from water. The comparison of membrane parameters like percent retention, permeate flux and backwash times for PAC/UF and MAC/UF hybrid processes showed that percent retention of paraquat and linuron was high for PAC due to its high surface area. However due to cake formation over membrane surface the decline permeate fluxes and long backwash times for PAC were observed. PAC also caused blackening of pipes and flow meter. MAC (an iron oxide and PAC composite) was removed from slurry through magnet thus no cake formation and secondary problems observed for PAC was not encountered. Also the backwash times were minimum for MAC/UF process. (author)

  5. Application of Ultrafiltration in a Paper Mill: Process Water Reuse and Membrane Fouling Analysis

    Directory of Open Access Journals (Sweden)

    Chen Chen

    2015-02-01

    Full Text Available High water consumption is a major environmental problem that the pulp and paper industry is facing. Ultrafiltration (UF can be used to remove the dissolved and colloidal substances (DCS concentrated during the recycling of white water (the process water to facilitate the reuse of white water and reduce fresh water consumption. However, membrane fouling limits the application of UF in this industry. In this study, super-clear filtrate obtained from a fine paper mill was purified with a polyethersulfone (PES ultrafiltration membrane to evaluate the reuse performance of the ultrafiltrate. The membrane foulants were characterized by scanning electron microscopy, energy-dispersive spectrophotometry, attenuated total reflection-fourier transform infrared spectroscopy, and gas chromatography-mass spectrometry. The results indicate that the retention rate of stock and the strength properties of paper increased when the ultrafiltrate was reused in the papermaking process compared to when super-clear filtrate was used. The reversible membrane foulants during ultrafiltration accounted for 85.52% of the total foulants and primarily originated from retention aids, drainage aids, and wet strength resins, while the irreversible adsorptive foulants accounted for 14.48% and mostly came from sizing agents, coating chemicals, and others. Moreover, the presence of dissolved multivalent metal ions, especially Ca2+, accelerated membrane fouling.

  6. Ultrafiltration Membrane Fouling and the Effect of Ion Exchange Resins

    KAUST Repository

    Jamaly, Sanaa

    2011-12-01

    Membrane fouling is a challenging process for the ultrafiltration membrane during wastewater treatment. This research paper determines the organic character of foulants of different kinds of wastewater before and after adding some ion exchange resins. Two advanced organic characterization methods are compared in terms of concentration of dissolved organic carbons: The liquid chromatography with organic carbon (LC-OCD) and Shimadzu total organic carbon (TOC). In this study, two secondary wastewater effluents were treated using ultrafiltration membrane. To reduce fouling, pretreatment using some adsorbents were used in the study. Six ion exchange resins out of twenty were chosen to compare the effect of adsorbents on fouling membrane. Based on the percent of dissolved organic carbon’s removal, three adsorbents were determined to be the most efficient (DOWEX Marathon 11 anion exchange resin, DOWEX Optipore SD2 polymeric adsorbent, and DOWEX PSR2 anion exchange), and three other ones were determined to the least efficient (DOWEX Marathon A2 anion exchange resin, DOWEX SAR anion exchange resin, and DOWEX Optipore L493 polymeric adsorbent). Organic characterization for feed, permeate, and backwash samples were tested using LC-OCD and TOC to better understand the characteristics of foulants to prevent ultrafiltration membrane fouling. The results suggested that the polymeric ion exchange resin, DOWEX SD2, reduced fouling potential for both treated wastewaters. All the six ion exchange resins removed more humic fraction than other organic fractions in different percent, so this fraction is not the main for cause for UF membrane fouling. The fouling of colloids was tested before and after adding calcium. There is a severe fouling after adding Ca2+ to effluent colloids.

  7. 21 CFR 177.2910 - Ultra-filtration membranes.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ultra-filtration membranes. 177.2910 Section 177... Components of Articles Intended for Repeated Use § 177.2910 Ultra-filtration membranes. Ultra-filtration membranes identified in paragraphs (a)(1), (a)(2), (a)(3), and (a)(4) of this section may be safely used in...

  8. Preparation of antifouling ultrafiltration membranes via irradiation induced graft polymerization technique

    International Nuclear Information System (INIS)

    Deng Bo; Liu Zhognying; Lu Xiaofeng; Li Jingye; Yang Xuanxuan; Yu Ming; Zhang Bowu

    2010-01-01

    PVDF powders were irradiated in air at dose of 15 kGy by using gamma-rays. Macromolecular peroxides transformed from free radicals in the irradiated PVDF powders in air can be preserved for long-term at appropriate temperature stably. By mixing acrylic monomers with irradiated PVDF powders then the graft polymerization can be initiated by heating. Then a series of hydrophilic ultrafiltration (UF) membranes were fabricated by dissolving the PVDF-g-PAAc powders in the NMP under phase inversion method. The antifouling performances of UF membranes cast from virgin and grafted PVDF powders were compared. (authors)

  9. Microfiltration and Ultrafiltration Membranes for Drinking Water

    Science.gov (United States)

    This article provides a concise and abbreviated summary of AWWA Manual of Practice M53, Microfiltration and Ultrafiltration Membranes for Drinking Water, to serve as a quick point of reference. For convenience, the article’s organization matches that of M53, as follows: • wate...

  10. SURVEY REGARDING THE ULTRAFILTRATION OF PROTEINES THROUGH MEMBRANE BASED PROCEDURES

    Directory of Open Access Journals (Sweden)

    CAMELIA HODOSAN

    2008-05-01

    Full Text Available This work is based on examples that emphasize the complexity of the proteins ultrafiltration process, pointing out the first 10-15 minutes of ultrafiltration. The knowledgement of the factors that influence the separation through ultrafiltration of proteins will allow to choose the right type of membrane, the frequent use of the same membrane and the operation in mechanical and chemical conditions adequate to the ultrafiltration system, when it is separated a protein with certain molecular weight.

  11. Dual-Functional Ultrafiltration Membrane for Simultaneous Removal of Multiple Pollutants with High Performance.

    Science.gov (United States)

    Pan, Shunlong; Li, Jiansheng; Noonan, Owen; Fang, Xiaofeng; Wan, Gaojie; Yu, Chengzhong; Wang, Lianjun

    2017-05-02

    Simultaneous removal of multiple pollutants from aqueous solution with less energy consumption is crucial in water purification. Here, a novel concept of dual-functional ultrafiltration (DFUF) membrane is demonstrated by entrapment of nanostructured adsorbents into the finger-like pores of ultrafiltration (UF) membrane rather than in the membrane matrix in previous reports of blend membranes, resulting in an exceptionally high active content and simultaneous removal of multiple pollutants from water due to the dual functions of rejection and adsorption. As a demonstration, hollow porous Zr(OH) x nanospheres (HPZNs) were immobilized in poly(ether sulfone) (PES) UF membranes through polydopamine coating with a high content of 68.9 wt %. The decontamination capacity of DFUF membranes toward multiple model pollutants (colloidal gold, polyethylene glycol (PEG), Pb(II)) was evaluated against a blend membrane. Compared to the blend membrane, the DFUF membranes showed 2.1-fold increase in the effective treatment volume for the treatment of Pb(II) contaminated water from 100 ppb to below 10 ppb (WHO drinking water standard). Simultaneously, the DFUF membranes effectively removed the colloidal gold and PEG below instrument detection limit, however the blend membrane only achieved 97.6% and 96.8% rejection for colloidal gold and PEG, respectively. Moreover, the DFUF membranes showed negligible leakage of nanoadsorbents during testing; and the membrane can be easily regenerated and reused. This study sheds new light on the design of high performance multifunction membranes for drinking water purification.

  12. ULTRAFILTRATION AS PRETREATMENT OF REVERSE OSMOSIS: LOW FOULING ULTRAFILTRATION MEMBRANE PREPARED FROM POLYETHERSULFONE–AMPHIPHILIC BLOCK COPOLYMER BLEND

    Directory of Open Access Journals (Sweden)

    Heru Susanto

    2012-02-01

    Full Text Available This paper demonstrates the preparation of polyethersulfone (PES ultrafiltration (UF membranes via wet phase inversion method using either poly(ethylene oxide-b-poly(propylene oxide-b- poly(ethylene oxide (Pluronic®, Plu or polyethylene glycol (PEG as hydrophilic modifier. Their effects on membrane structure as well as the resulting membrane performance and their stability in membrane polymer matrix were systematically investigated. The investigated membrane characteristics include surface hydrophilicity (by contact angle, surface chemistry (by FTIR spectroscopy and water flux measurement. Visualization of membrane surface and cross section morphology was also done by scanning electron microscopy. The membrane performance was examined by investigation of adsorptive fouling and ultrafiltration using solution of bovine serum albumin as the model system. The stability of additive was examined by incubating the membrane in water (40oC for up to 10 days. The results show that modification effects on membrane characteristic and low fouling behavior were clearly observed. Further, amphiphilic Pluronic generally showed better performance than PEG.   

  13. Adsorption of amylase enzyme on ultrafiltration membranes

    DEFF Research Database (Denmark)

    Beier, Søren; Enevoldsen, Ann Dorrit; Kontogeorgis, Georgios

    2007-01-01

    A method to measure the static adsorption on membrane surfaces has been developed and described. The static adsorption of an amylase-F has been measured on two different ultrafiltration membranes, both with a cut-off value of 10 kDa (a PES membrane and the ETNA10PP membrane, which is a surface......-modified PVDF membrane). The adsorption follows the Langmuir adsorption theory. Thus, the static adsorption consists of monolayer coverage. The static adsorption is expressed both as a permeability drop and an adsorption resistance. From the adsorption isotherms the maximum static permeability drops...... and the maximum static adsorption resistances are determined. The maximum static permeability drop for the hydrophobic PES membrane is 75 % and the maximum static adsorption resistance is 0.014 m2hbar/L. The maximum static permeability drop for the hydrophilic surface-modified PVDF membrane (ETNA10PP) is 23...

  14. Ultrafiltration by gyroid nanoporous polymer membranes

    DEFF Research Database (Denmark)

    Li, Li; Szewczykowski, Piotr Przemyslaw; Clausen, Lydia D.

    2011-01-01

    the effect of membrane fouling on the flux decline and rejection profiles. Significant fouling occurred in the case of hydrophobic membranes in contact with water solutions, while in the presence of high concentration of ethanol in the filtration solution and in the case of hydrophilized membranes...... the fouling was reduced. The observed rejection of PEG was compared with theoretic predictions, as described by the Bungay–Brenner model. The model satisfactorily described the rejection profile of PEG up to 12kg/mol through hydrophobic membranes in the presence of excess ethanol. A significantly reduced......Gyroid nanoporous cross-linked 1,2-polybutadiene membranes with uniform pores were developed for ultrafiltration applications. The gyroid porosity has the advantage of isotropic percolation with no need for structure pre-alignment. The effects of solvent and surface photo...

  15. A STUDY OF BRACKISH WATER MEMBRANE WITH ULTRAFILTRATION PRETREATMENT IN INDONESIA´S COASTAL AREA

    Directory of Open Access Journals (Sweden)

    Elis Hastuti

    2012-01-01

    Full Text Available Water pollution and sea water intrusion to water sources in coastal areas result lack of provision safe drinking water by the drinking water regional company or coastal community. The existing water treatment plant that operated on brackish surface water or groundwater feed requires improving process. Membrane process could be a choice to treat the quality of brackish water to the level of potable water that designed to lower cost with high stabil flux and longer lifetime. This research focus on application of pilot plant of brackish water treatment using Ultrafiltration (UF membrane-air lift system as pretreatment of Reverse Osmosis (RO membrane-low pressure. Brackish water sources contain high colloidal and suspended solids that can cause fouling load of RO membranes and impair its performance. UF pretreatment operation tested by addition of compressed air into the feed (air lift system, resulted stable flux, reduces membrane fouling and low feed pressure. A flux of RO with UF pretreatment can produce drinking water of 30--61 L/m2·hour. It was observed, the good quality of RO permeate resulted by using a pretreatment of UF--PS (Polysulfone-UF with total dissolved solid rejection about 96--98% and color rejection about 99--100% at 5 or 8 bars of operation pressure. This paper concludes that performance of membrane technology with UF--air lift system pretreatment and RO membrane-low pressure could be accepted as condition of brackish water source in Indonesia coastal areas in producing drinking water.

  16. Fouling Characteristics of Dissolved Organic Matter in Papermaking Process Water on Polyethersulfone Ultrafiltration Membranes

    Directory of Open Access Journals (Sweden)

    Wenpeng Su

    2015-07-01

    Full Text Available In the papermaking industry, closure of process water (whitewater circuits has been used to reduce fresh water consumption. Membrane separation technology has potential for use in treating process water for recirculation. The purpose of this study was to reveal the fouling characteristics of a polyethersulfone (PES ultrafiltration membrane caused by dissolved organic matter (DOM in process water. Ultrafiltration membranes (UF and DAX ion exchange resins were applied to characterize the molecular weight (MW and hydrophilicity distribution of DOM. The interactions between various fractions of DOM and a PES ultrafiltration membrane were investigated. The membrane fouling characteristics were elucidated by examining the filtration resistances and linearized Herman’s blocking models. The results demonstrated that the membrane was fouled significantly by much of the MW distribution. The membrane was fouled more significantly by the low MW fraction rather than the high MW fraction. The filtration resistances and the fitted equation of Hermia’s laws indicated that hydrophilic organics were the main foulants. The hydrophilic organics partially block the membrane pores and form intermediate blocking, reducing the effective filtration area, while the hydrophobic organics form a gel layer or cake on the surface of the membrane.

  17. EFFICIENCY OF ULTRAFILTRATION CERAMIC MEMBRANES FOR TOXIC ELEMENTS REMOVAL FROM WASTEWATERS

    Directory of Open Access Journals (Sweden)

    S. Alami Younssi

    2010-07-01

    Full Text Available The preparation and characterization of porous ceramics multilayer ultrafiltration membrane is described. The first step consisted to prepare high-quality macroporous support in Moroccan clay. The choice of this material is based on its natural abundance and thermal stability.The microporous interlayer was then prepared by slip casting from zirconia commercial powders and finally the active UF toplayers was obtained by sol-gel route using ZnAl2O4 and TiO2 mixed sols. The performance of ultrafiltration membrane (TiO2 (50�20– ZnAl2O4 (50� was evaluated by pores diameter, water flux, thickness and molecular weight cut off (MWCO. The water permeability measured for this composite membrane is 9.42 L/(m2•h•bar, the thickness is less than 700 nm, the pore diameter is centered near 5 nm and the MWCO was about 4500 Da.

  18. Impact of granular filtration on ultrafiltration membrane performance as pre-treatment to seawater desalination in presence of algal blooms

    Directory of Open Access Journals (Sweden)

    Nour-Eddine Sabiri

    2018-04-01

    Full Text Available To mitigate fouling of the ultrafiltration (UF membrane and improve permeate quality, we coupled granular filters (GF with UF membrane as a pre-treatment for reconstituted seawater in the presence of algal bloom. Mono and bilayer granular filtrations were led at a mean velocity of 10 m h−1 over a 7-hour period. Both GF gave the same algal cell retention rate (∼63% after 7 hours of filtration. Turbidity reduction rate was 50% for the monolayer filter and 75% for the bilayer filter. Resulting organic matter removal rate was 10% for the monolayer filter and 35% for the bilayer filter. Dissolved organic carbon removal was low (20% with the bilayer filter and non-existent with the monolayer filter. GF-coupled UF reduced humic acids in the permeate (20% compared with UF alone. Peak pressure of 3 bars was reached at the end of 30 minutes of UF in both direct UF or UF after monolayer GF. The filtrate from the bilayer GF enables UF over a longer period (7 hours.

  19. Fabrication of TiO_2-modified polytetrafluoroethylene ultrafiltration membranes via plasma-enhanced surface graft pretreatment

    International Nuclear Information System (INIS)

    Qian, Yingjia; Chi, Lina; Zhou, Weili; Yu, Zhenjiang; Zhang, Zhongzhi; Zhang, Zhenjia; Jiang, Zheng

    2016-01-01

    Graphical abstract: - Highlights: • Multifunctional TiO_2/PAA/PTFE ultrafiltration membrane was fabricated via tight coating of TiO_2 functional layer onto the plasma-assisted graft of PAA on PTFE. • The high water flux rate, remarkable enhanced ultrafiltration performance and excellent self-cleaning ability were demonstrated. • The formation of COO−Ti bidentate coordination between TiO_2 and PAA was responsible for the successful coating. - Abstract: Surface hydrophilic modification of polymer ultrafiltration membrane using metal oxide represents an effective yet highly challenging solution to improve water flux and antifouling performance. Via plasma-enhanced graft of poly acryl acid (PAA) prior to coating TiO_2, we successfully fixed TiO_2 functional thin layer on super hydrophobic polytetrafluoroethylene (PTFE) ultrafiltration (UF) membranes. The characterization results evidenced TiO_2 attached on the PTFE-based UF membranes through the chelating bidentate coordination between surface-grafted carboxyl group and Ti"4"+. The TiO_2 surface modification may greatly reduce the water contact angle from 115.8° of the PTFE membrane to 35.0° without degradation in 30-day continuous filtration operations. The novel TiO_2/PAA/PTFE membranes also exhibited excellent antifouling and self-cleaning performance due to the intrinsic hydrophilicity and photocatalysis properties of TiO_2, which was further confirmed by the photo-degradation of MB under Xe lamp irradiation.

  20. Cleaning UF membranes with simple and formulated solutions

    NARCIS (Netherlands)

    Levitsky, I.; Duek, A.; Naim, R.; Arkhangelsky, E.; Gitis, V.

    2012-01-01

    The ultrafiltration membranes fouled by proteins are typically cleaned by consecutive soaking in alkali, surfactant and oxidizing solutions. We combined all three chemicals into a formulated cleaning agent and examined its efficiency to restore the water flux without damaging the membrane or

  1. Polyethersulfone-based ultrafiltration hollow fibre membrane for drinking water treatment systems

    Science.gov (United States)

    Chew, Chun Ming; Ng, K. M. David; Ooi, H. H. Richard

    2017-12-01

    Conventional media/sand filtration has been the mainstream water treatment process for most municipal water treatment plants in Malaysia. Filtrate qualities of conventional media/sand filtration are very much dependent on the coagulation-flocculation process prior to filtration and might be as high as 5 NTU. However, the demands for better quality of drinking water through public piped-water supply systems are growing. Polymeric ultrafiltration (UF) hollow fibre membrane made from modified polyethersulfone (PES) material is highly hydrophilic with high tensile strength and produces excellent quality filtrate of below 0.3 NTU in turbidity. This advanced membrane filtration material is also chemical resistance which allows a typical lifespan of 5 years. Comparisons between the conventional media/sand filtration and PES-based UF systems are carried out in this paper. UF has been considered as the emerging technology in municipal drinking water treatment plants due to its consistency in producing high quality filtrates even without the coagulation-flocculation process. The decreasing cost of PES-based membrane due to mass production and competitive pricing by manufacturers has made the UF technology affordable for industrial-scale water treatment plants.

  2. On the use of ultrafiltration membranes in oily water separators

    Energy Technology Data Exchange (ETDEWEB)

    Tremblay, A.Y.; Nottegar, M. [Ottawa Univ., ON (Canada). Dept. of Chemical Engineering; Veinot, D.E. [Defence Research Establishment Atlantic, Halifax, NS (Canada)

    2000-07-01

    Laboratory studies were conducted on the use of ultrafiltration membranes for oil water purification from ships bilges. Bilge water is a complex and highly variable mixture of several components such as seawater, lubricating oil, greases, marine diesel fuel, hydraulic oil, detergents, metal oxides, corrosion inhibitors, asbestos and other wastes. This laboratory study examined the performance of ultrafiltration membranes when separating oily waste water of similar composition to that of bilge water. Ultrafiltration membranes are nanoporous materials produced from ceramic, polymeric or metallic substrates. The ability of the membrane to retain macromolecules, colloids, sub-micron particles and oil emulsions depends on the size of the nanopores. The best results in this study occurred when upper and lower bounds on the membrane pore size were found to exist. It was determined that ultrafiltration is a viable separation process for the treatment of bilge water for compliance with overboard discharge regulations. 7 refs., 1 tab., 3 figs.

  3. Experimental study of lactose hydrolysis and separation in cstr-uf membrane reactor

    Directory of Open Access Journals (Sweden)

    M. Namvar-Mahboub

    2012-09-01

    Full Text Available In this study, the effect of processing conditions on the performance of continuous stirred tank -ultrafiltration (CSTR-UF in dead - end mode was investigated. An UF membrane with a molecular weight cutoff of 3 kDa made of regenerated cellulose material was used to separate enzyme from products. The effect of operating pressure ranging between 2 and 5 bar and time on the performance of the CSTR-UF system was studied. The experiments were performed with a 0.139 molar aqueous solution of lactose as feed. According to the experimental data, the lactose concentration in the permeate decreased with time due to concentration polarization and hydrolysis. It was found that the rejection factor of lactose increases from 33 to 77% with time from 5 to 85 min. Permeation flux of the membrane was evaluated in terms of pure water flux (PWF and lactose aqueous solution. Results showed that a high operating pressure led to a high permeation flux for both mentioned cases. Also, adding lactose and enzyme to pure water caused a reduction of the permeation flux due to concentration polarization.

  4. Physical–chemical properties, separation performance, and fouling resistance of mixed-matrix ultrafiltration membranes

    KAUST Repository

    Hoek, Eric M.V.; Ghosh, Asim K.; Huang, Xiaofei; Liong, Monty; Zink, Jeffrey I.

    2011-01-01

    Herein we report on the formation and characterization of mixed-matrix ultrafiltration (UF) membranes hand-cast by nonsolvent induced phase inversion. We evaluated nanometer-to-micrometer sized inorganic fillers (silver, copper, silica, zeolite, and silver-zeolite) materials with polysulfone (PSf) as the polymeric dispersing matrix. In general, mixed-matrix membranes were rougher, more hydrophilic, and more mechanically robust. Only sub-micron zeolite-PSf mixed-matrix membranes exhibited simultaneous improvements in water permeability and solute selectivity; all other mixed-matrix membranes were more permeable, but less selective due to defects associated with poor polymer-filler binding. Protein and bacterial fouling resistance of mixed-matrix membranes containing silver, zeolite, and silver-zeolite nanoparticles were compared to a low-fouling, poly(acrylonitrile) (PAN) UF membrane. Zeolite and silver containing membranes exhibited better protein fouling resistance (due to higher hydrophilicity), whereas silver and silver-zeolite based membranes produce better bacterial fouling resistance due to antimicrobial properties. Overall, zeolite-PSf and silver exchanged zeolite-PSf membranes offered the best combination of improved permeability, selectivity, and fouling resistance - superior to the commercial PAN membrane. © 2011 Elsevier B.V.

  5. Physical–chemical properties, separation performance, and fouling resistance of mixed-matrix ultrafiltration membranes

    KAUST Repository

    Hoek, Eric M.V.

    2011-12-01

    Herein we report on the formation and characterization of mixed-matrix ultrafiltration (UF) membranes hand-cast by nonsolvent induced phase inversion. We evaluated nanometer-to-micrometer sized inorganic fillers (silver, copper, silica, zeolite, and silver-zeolite) materials with polysulfone (PSf) as the polymeric dispersing matrix. In general, mixed-matrix membranes were rougher, more hydrophilic, and more mechanically robust. Only sub-micron zeolite-PSf mixed-matrix membranes exhibited simultaneous improvements in water permeability and solute selectivity; all other mixed-matrix membranes were more permeable, but less selective due to defects associated with poor polymer-filler binding. Protein and bacterial fouling resistance of mixed-matrix membranes containing silver, zeolite, and silver-zeolite nanoparticles were compared to a low-fouling, poly(acrylonitrile) (PAN) UF membrane. Zeolite and silver containing membranes exhibited better protein fouling resistance (due to higher hydrophilicity), whereas silver and silver-zeolite based membranes produce better bacterial fouling resistance due to antimicrobial properties. Overall, zeolite-PSf and silver exchanged zeolite-PSf membranes offered the best combination of improved permeability, selectivity, and fouling resistance - superior to the commercial PAN membrane. © 2011 Elsevier B.V.

  6. Low fouling polysulfone ultrafiltration membrane via click chemistry

    KAUST Repository

    Xie, Yihui; Tayouo Djinsu, Russell; Nunes, Suzana Pereira

    2014-01-01

    %, and 94%). The glass transition temperature shifted with the introduction of triazole pendant groups from 190°C (unmodified) to 171°C. Ultrafiltration membranes were prepared via phase inversion by immersion in different coagulation baths (NMP

  7. Removal of trace organic chemicals and performance of a novel hybrid ultrafiltration-osmotic membrane bioreactor.

    Science.gov (United States)

    Holloway, Ryan W; Regnery, Julia; Nghiem, Long D; Cath, Tzahi Y

    2014-09-16

    A hybrid ultrafiltration-osmotic membrane bioreactor (UFO-MBR) was investigated for over 35 days for nutrient and trace organic chemical (TOrC) removal from municipal wastewater. The UFO-MBR system uses both ultrafiltration (UF) and forward osmosis (FO) membranes in parallel to simultaneously extract clean water from an activated sludge reactor for nonpotable (or environmental discharge) and potable reuse, respectively. In the FO stream, water is drawn by osmosis from activated sludge through an FO membrane into a draw solution (DS), which becomes diluted during the process. A reverse osmosis (RO) system is then used to reconcentrate the diluted DS and produce clean water suitable for direct potable reuse. The UF membrane extracts water, dissolved salts, and some nutrients from the system to prevent their accumulation in the activated sludge of the osmotic MBR. The UF permeate can be used for nonpotable reuse purposes (e.g., irrigation and toilet flushing). Results from UFO-MBR investigation illustrated that the chemical oxygen demand, total nitrogen, and total phosphorus removals were greater than 99%, 82%, and 99%, respectively. Twenty TOrCs were detected in the municipal wastewater that was used as feed to the UFO-MBR system. Among these 20 TOrCs, 15 were removed by the hybrid UFO-MBR system to below the detection limit. High FO membrane rejection was observed for all ionic and nonionic hydrophilic TOrCs and lower rejection was observed for nonionic hydrophobic TOrCs. With the exceptions of bisphenol A and DEET, all TOrCs that were detected in the DS were well rejected by the RO membrane. Overall, the UFO-MBR can operate sustainably and has the potential to be utilized for direct potable reuse applications.

  8. Evaluation of biochar-ultrafiltration membrane processes for humic acid removal under various hydrodynamic, pH, ionic strength, and pressure conditions.

    Science.gov (United States)

    Shankar, Vaibhavi; Heo, Jiyong; Al-Hamadani, Yasir A J; Park, Chang Min; Chu, Kyoung Hoon; Yoon, Yeomin

    2017-07-15

    The performance of an ultrafiltration (UF)-biochar process was evaluated in comparison with a UF membrane process for the removal of humic acid (HA). Bench-scale UF experiments were conducted to study the rejection and flux trends under various hydrodynamic, pH, ionic strength, and pressure conditions. The resistance-in-series model was used to evaluate the processes and it showed that unlike stirred conditions, where low fouling resistance was observed (28.7 × 10 12  m -1 to 32.5 × 10 12  m -1 ), higher values and comparable trends were obtained for UF-biochar and UF alone for unstirred conditions (28.7 × 10 12  m -1 to 32.5 × 10 12  m -1 ). Thus, the processes were further evaluated under unstirred conditions. Additionally, total fouling resistance was decreased in the presence of biochar by 6%, indicating that HA adsorption by biochar could diminish adsorption fouling on the UF membrane and thus improve the efficiency of the UF-biochar process. The rejection trends of UF-biochar and UF alone were similar in most cases, whereas UF-biochar showed a noticeable increase in flux of around 18-25% under various experimental conditions due to reduced membrane fouling. Three-cycle filtration tests further demonstrated that UF-biochar showed better membrane recovery and antifouling capability by showing more HA rejection (3-5%) than UF membrane alone with each subsequent cycle of filtration. As a result of these findings, the UF-biochar process may potentially prove be a viable treatment option for the removal of HA from water. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. A study of brackish water membrane with ultrafiltration pretreatment in Indonesia’s coastal area

    Directory of Open Access Journals (Sweden)

    Elis Hastuti

    2012-06-01

    Full Text Available Water pollution and sea water intrusion to water sources in coastal areas result lack of provision safe drinking water by the drinking water regional company or coastal community. The existing water treatment plant that operated on brackish surface water or groundwater feed requires improving process. Membrane process could be a choice to treat the quality of brackish water to the level of potable water that designed to lower cost with high stabil flux and longer lifetime. This research focus on application of pilot plant of brackish water treatment using Ultrafiltration (UF membrane-air lift system as pretreatment of Reverse Osmosis (RO membrane-low pressure. Brackish water sources contain high colloidal and suspended solids that can cause fouling load of RO membranes and impair its performance. UF pretreatment operation tested by addition of compressed air into the feed (air lift system, resulted stable flux, reduces membrane fouling and low feed pressure. A flux of RO with UF pretreatment can produce drinking water of 30–61 L/m2∙hour. It was observed, the good quality of RO permeate resulted by using a pretreatment of UF–PS (Polysulfone-UF with total dissolved solid rejection about 96–98% and color rejection about 99–100% at 5 or 8 bars of operation pressure. This paper concludes that performance of membrane technology with UF–air lift system pretreatment and RO membrane-low pressure could be accepted as condition of brackish water source in Indonesia coastal areas in producing drinking water.

  10. Tight ceramic UF membrane as RO pre-treatment: the role of electrostatic interactions on phosphate rejection.

    Science.gov (United States)

    Shang, Ran; Verliefde, Arne R D; Hu, Jingyi; Zeng, Zheyi; Lu, Jie; Kemperman, Antoine J B; Deng, Huiping; Nijmeijer, Kitty; Heijman, Sebastiaan G J; Rietveld, Luuk C

    2014-01-01

    Phosphate limitation has been reported as an effective approach to inhibit biofouling in reverse osmosis (RO) systems for water purification. The rejection of dissolved phosphate by negatively charged TiO2 tight ultrafiltration (UF) membranes (1 kDa and 3 kDa) was observed. These membranes can potentially be adopted as an effective process for RO pre-treatment in order to constrain biofouling by phosphate limitation. This paper focuses on electrostatic interactions during tight UF filtration. Despite the larger pore size, the 3 kDa ceramic membrane exhibited greater phosphate rejection than the 1 kDa membrane, because the 3 kDa membrane has a greater negative surface charge and thus greater electrostatic repulsion against phosphate. The increase of pH from 6 to 8.5 led to a substantial increase in phosphate rejection by both membranes due to increased electrostatic repulsion. At pH 8.5, the maximum phosphate rejections achieved by the 1 kDa and 3 kDa membrane were 75% and 86%, respectively. A Debye ratio (ratio of the Debye length to the pore radius) is introduced in order to evaluate double layer overlapping in tight UF membranes. Threshold Debye ratios were determined as 2 and 1 for the 1 kDa and 3 kDa membranes, respectively. A Debye ratio below the threshold Debye ratio leads to dramatically decreased phosphate rejection by tight UF membranes. The phosphate rejection by the tight UF, in combination with chemical phosphate removal by coagulation, might accomplish phosphate-limited conditions for biological growth and thus prevent biofouling in the RO systems. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Preparation and characterization of novel zwitterionic poly(arylene ether sulfone) ultrafiltration membrane with good thermostability and excellent antifouling properties

    Science.gov (United States)

    Rong, Guolong; Zhou, Di; Han, Xiaocui; Pang, Jinhui

    2018-01-01

    Zwitterionic poly(arylene ether sulfone) (PAES-NS) was synthesized via copolymerization by using a bisphenol monomer with a pyridine group. The chemical structures of the copolymers were confirmed by using Fourier transform infrared (FTIR) and 1H nuclear magnetic resonance (NMR) spectroscopy; the copolymers showed good thermal stability. A series of polyphenysulfone (PPSU)/PAES-NS blend ultrafiltration (UF) membranes was prepared via conventional immersion precipitation phase inversion methods The morphologies of the modified membranes were investigated by scanning electron microscopy (SEM). The surface hydrophilicity of the UF membranes was studied by water contact angle measurement, indicating that the zwitterionic group increased the membrane hydrophilicity. UF of solvated model pollutants using the membranes showed a significant reduction of the irreversible adsorption of the foulants, illustrating the excellent anti-fouling properties of the membrane. The water flux of the PAES-NS membrane was significantly enhanced, being almost three times higher than that of the pristine PPSU membrane, with retention of a high rejection level. After three UF cycles, the water flux recovery of the PAES-NS membrane was as high as 96%.

  12. Clay filter-aid in ultrafiltration (UF) of humic acid solution

    KAUST Repository

    Pontié , M.; Thekkedath, A.; Kecili, K.; Dach, H.; De Nardi, F.; Castaing, J.B.

    2012-01-01

    Fouling studies with three different molecular weight cut-off (MWCO) (100. kDa, 30. kDa and 10. kDa) membranes in regenerated cellulose were carried out in the presence of Acros humic acids (HA) at pH 3.0, 6.7 and 9.5. It was shown that the tighter membranes were less fouled compared with the higher MWCO membranes. 100. kDa membrane showed the highest degree of fouling. The role of pH showed that the highest degree of fouling happened at a neutral pH (pH 6.7) and the lowest degree of fouling happened at a basic pH (pH 9.5).Effectiveness of a novel pre-treatment method was applied to the 100kDa membrane. We added in the HA solution clay particles, homemade synthetized from natural bentonite and denoted Mont-CTAB. We observed a gain in productivity of 25%. 2D-fractal dimension parameter decreased under 1.5, showing a de-organization of the cake due to clay particles in/on the cake and a specific resistance of 4.4×10 11m/kg was obtained in presence of clays versus 3.6×10 14m/kg with HA alone. Finally the development of clay assisted ultrafiltration process changes the cake morphology limiting fouling impact and it is hope that for long term experiments, formation of a gel-layer should be limited. © 2012 Elsevier B.V..

  13. Clay filter-aid in ultrafiltration (UF) of humic acid solution

    KAUST Repository

    Pontié, M.

    2012-04-01

    Fouling studies with three different molecular weight cut-off (MWCO) (100. kDa, 30. kDa and 10. kDa) membranes in regenerated cellulose were carried out in the presence of Acros humic acids (HA) at pH 3.0, 6.7 and 9.5. It was shown that the tighter membranes were less fouled compared with the higher MWCO membranes. 100. kDa membrane showed the highest degree of fouling. The role of pH showed that the highest degree of fouling happened at a neutral pH (pH 6.7) and the lowest degree of fouling happened at a basic pH (pH 9.5).Effectiveness of a novel pre-treatment method was applied to the 100kDa membrane. We added in the HA solution clay particles, homemade synthetized from natural bentonite and denoted Mont-CTAB. We observed a gain in productivity of 25%. 2D-fractal dimension parameter decreased under 1.5, showing a de-organization of the cake due to clay particles in/on the cake and a specific resistance of 4.4×10 11m/kg was obtained in presence of clays versus 3.6×10 14m/kg with HA alone. Finally the development of clay assisted ultrafiltration process changes the cake morphology limiting fouling impact and it is hope that for long term experiments, formation of a gel-layer should be limited. © 2012 Elsevier B.V..

  14. Carbon dioxide nucleation as a novel cleaning method for ultrafiltration membranes

    KAUST Repository

    Al Ghamdi, Mohanned

    2016-12-08

    The use of low-pressure membranes, mainly ultrafiltration (UF), has emerged in the last decade and began to show acceptance as a novel pretreatment process for seawater reverse osmosis (SWRO) desalination. This is mainly due to the superior water quality provided by these membranes, in addition to reduction in chemicals consumption compared to conventional methods. However, membrane fouling remains the main drawback of this technology. Therefore, frequent cleaning of these membranes is required to maintain water flux and its quality. Usually, after a series of backwash using UF permeate chemical cleaning is required under some conditions to fully recover the operating flux. Frequent chemical cleaning will probably decrease the life time of the membrane, increase costs, and will have some effects on the environment. The new cleaning method proposed in this study consists of using a solution saturated with carbon dioxide (CO2) to clean UF membranes. Under the drop in pressure, this solution will become in a supersaturated state and bubbles will start to nucleate on the surface of the membrane and its pores from this solution resulting in the removal of the fouling material deposited on the membrane. Different compositions of fouling solutions including the use of organic compounds such as sodium alginate and colloidal 5 silica with different concentrations were studied using synthetic seawater with different concentrations. This cleaning method was then compared to the backwash using Milli-Q water and showed an improved performance compared to it. An operational modification to this cleaning technique was then investigated which includs a series of sudden pressure drop during the backwash process. This enhanced technique showed an even better performance in cleaning the membrane, especially at severe fouling conditions. In most cases, the membrane permeability was fully recovered even at harsh conditions where conventional backwash failed to maintain a stable

  15. Processing radioactive wastes using membrane (UF/HF/RO) systems

    International Nuclear Information System (INIS)

    Doyle, R.D.

    1988-01-01

    Over the years many technologies have been utilized to process low level radioactive waste streams generated by the nuclear industry, including: demineralization, evaporation, reverse osmosis and filtration. In the early 1980's interest was generated in membrane technologies and their application to radioactive wastes. This interest was generated based on the capabilities shown by membrane systems in non-radioactive environments and the promise that reverse osmosis systems showed in early testing with radioactive wastes. Membrane technologies have developed from the early development of reverse osmosis system to also include specifically designed membranes for ultrafiltration and hyperfiltration applications

  16. CROSS-FLOW ULTRAFILTRATION OF SECONDARY EFFLUENTS. MEMBRANE FOULING ANALYSIS

    Directory of Open Access Journals (Sweden)

    Luisa Vera

    2014-12-01

    Full Text Available The application of cross-flow ultrafiltration to regenerate secondary effluents is limited by membrane fouling. This work analyzes the influence of the main operational parameters (transmembrane pressure and cross-flow velocity about the selectivity and fouling observed in an ultrafiltration tubular ceramic membrane. The experimental results have shown a significant retention of the microcolloidal and soluble organic matter (52 – 54% in the membrane. The fouling analysis has defined the critical operational conditions where the fouling resistance is minimized. Such conditions can be described in terms of a dimensionless number known as shear stress number and its relationship with other dimensionless parameter, the fouling number.

  17. Effect of membrane properties on the performance of a hybrid GAC and ultrafiltration process for water treatment.

    Science.gov (United States)

    Qiao, Tiejun; Wu, Guangxue; Zhang, Xihui; Au, Doris W T; Zhang, Jinsong

    2012-06-01

    The performance of a hybrid granular activated carbon (GAC) and ultrafiltration (UF) process for water treatment was investigated using five types of UF membranes. The removal percentages for chemical oxygen demand (COD(Mn)), particles (> or = 2 microm) and total bacteria by the hybrid process were 30-40%, 98-99% and 76-92%, respectively. No invertebrates were detected in the hybrid process effluent. Transmembrane pressure and specific permeate flux (SPF) of the five types of membranes varied. With decreasing membrane pore sizes, removal of COD(Mn) and particles increased, whereas SPF firstly decreased and then increased. Hydrophilic membranes had a relatively high COD(Mn) removal potential, but did not obviously affect particle removal or SPF.

  18. Reducing ultrafiltration membrane fouling during potable water reuse using pre-ozonation.

    Science.gov (United States)

    Wang, Hui; Park, Minkyu; Liang, Heng; Wu, Shimin; Lopez, Israel J; Ji, Weikang; Li, Guibai; Snyder, Shane A

    2017-11-15

    Wastewater reclamation has increasingly become popular to secure potable water supply. Low-pressure membrane processes such as microfiltration (MF) and ultrafiltration (UF) play imperative roles as a barrier of macromolecules for such purpose, but are often limited by membrane fouling. Effluent organic matter (EfOM), including biopolymers and particulates, in secondary wastewater effluents have been known to be major foulants in low-pressure membrane processes. Hence, the primary aim of this study was to investigate the effects of pre-ozonation as a pre-treatment for UF on the membrane fouling caused by EfOM in secondary wastewater effluents for hydrophilic regenerated cellulose (RC) and hydrophobic polyethersulfone (PES) UF membranes. It was found that greater fouling reduction was achieved by pre-ozonation for the hydrophilic RC membrane than the hydrophobic PES membrane at increasing ozone doses. In addition, the physicochemical property changes of EfOM, including biopolymer fractions, by pre-ozonation were systemically investigated. The classical pore blocking model and the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theories were employed to scrutinize the fouling alleviation mechanism by pre-ozonation. As a result, the overarching mechanisms of fouling reduction were attributed to the following key reasons: (1) Ozone degraded macromolecules such as biopolymers like proteins and polysaccharides into smaller fractions, thereby increasing free energy of cohesion of EfOM and rendering them more hydrophilic and stable; (2) pre-ozonation augmented the interfacial free energy of adhesion between foulants and the RC/PES membranes, leading to the increase of repulsions and/or the decrease of attractions; and (3) pre-ozonation prolonged the transition from pore blocking to cake filtration that was a dominant fouling mechanism, thereby reducing fouling. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Effect of Time in Chemical Cleaning of Ultrafiltration Membranes

    NARCIS (Netherlands)

    Levitsky, I.; Naim, R.; Duek, A.; Gitis, V.

    2012-01-01

    Chemical cleaning of ultrafiltration membranes is often considered successful when the flux through a cleaned membrane is much higher than through a pristine one. Here, a novel definition of cleaning intensity is proposed as the product of the concentration of the cleaning agent and the cleaning

  20. Impact of Acid Cleaning on the Performance of PVDF UF Membranes in Seawater Reverse Osmosis Pretreatment

    KAUST Repository

    Alsogair, Safiya

    2016-05-05

    Low-pressure membrane systems such as Microfiltration (MF) and Ultrafiltration (UF) have been presented as viable option to pre-treatment systems in potable water applications. UF membranes are sporadically backwashed with ultra-filtered water to remove deposited matter from the membrane and restore it. Several factors that may cause permeability and selectivity decrease are involved and numerous procedures are applicable to achieve this objective. Membrane cleaning is the most important step required to maintain the characteristics of the membrane. This research was made with the purpose of investigating the effects of acid cleaning during chemically enhanced backwashing (CEB) on the performance of ultrafiltration (UF) membranes in seawater reverse osmosis (SWRO) pretreatment. To accomplish this, the questions made were: Does the acid addition (before or after the alkali CEB) influence the overall CEB cleaning effectiveness on Dow UF membrane? Does the CEB order of alkali (NaOCl) and acid (H2SO4) affect the overall CEB cleaning effectiveness? If yes, which order is better/worse? What is the optimal acid CEB frequency that will ensure the most reliable performance of the UF?. To answer this queries, a series of sequences were carried out with different types of chemical treatments: Only NaOCl, daily NaOCl plus weekly acid, daily NaOCl plus daily acid, and weekly acid plus daily NaOCl. To investigate the consequence of acid by studying the effect of operational data like the trans-pressure membrane, resistance or permeability and support that by the analytical experiments (organic, inorganic and microbial characterization). Microorganisms were removed almost completely at hydraulic cleaning and showed no difference with addition of acid. As a conclusion of the operational data the organic and inorganic chatacterization resulted in the elimination of the first sequence due to the acummulation of fouling over time, which produces that the cleaning increases downtime

  1. Highly Hydrophilic Polyvinylidene Fluoride (PVDF) Ultrafiltration Membranes via Postfabrication Grafting of Surface-Tailored Silica Nanoparticles

    KAUST Repository

    Liang, Shuai

    2013-07-24

    Polyvinylidene fluoride (PVDF) has drawn much attention as a predominant ultrafiltration (UF) membrane material due to its outstanding mechanical and physicochemical properties. However, current applications suffer from the low fouling resistance of the PVDF membrane due to the intrinsic hydrophobic property of the membrane. The present study demonstrates a novel approach for the fabrication of a highly hydrophilic PVDF UF membrane via postfabrication tethering of superhydrophilic silica nanoparticles (NPs) to the membrane surface. The pristine PVDF membrane was grafted with poly(methacrylic acid) (PMAA) by plasma induced graft copolymerization, providing sufficient carboxyl groups as anchor sites for the binding of silica NPs, which were surface-tailored with amine-terminated cationic ligands. The NP binding was achieved through a remarkably simple and effective dip-coating technique in the presence or absence of the N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC)/N-hydroxysuccinimide (NHS) cross-linking process. The properties of the membrane prepared from the modification without EDC/NHS cross-linking were comparable to those for the membrane prepared with the EDC/NHS cross-linking. Both modifications almost doubled the surface energy of the functionalized membranes, which significantly improved the wettability of the membrane and converted the membrane surface from hydrophobic to highly hydrophilic. The irreversibly bound layer of superhydrophilic silica NPs endowed the membranes with strong antifouling performance as demonstrated by three sequential fouling filtration runs using bovine serum albumin (BSA) as a model organic foulant. The results suggest promising applications of the postfabrication surface modification technique in various membrane separation areas. © 2013 American Chemical Society.

  2. Ultrafiltration technology with a ceramic membrane for reactive dye removal: optimization of membrane performance.

    Science.gov (United States)

    Alventosa-deLara, E; Barredo-Damas, S; Alcaina-Miranda, M I; Iborra-Clar, M I

    2012-03-30

    An ultrafiltration (UF) ceramic membrane was used to decolorize Reactive Black 5 (RB5) solutions at different dye concentrations (50 and 500 mg/L). Transmembrane pressure (TMP) and cross-flow velocity (CFV) were modified to study their influence on initial and steady-state permeate flux (J(p)) and dye rejection (R). Generally, J(p) increased with higher TMP and CFV and lower feed concentration, up to a maximum steady-state J(p) of 266.81 L/(m(2)h), obtained at 3 bar, 3m/s and 50mg/L. However, there was a TMP value (which changed depending on operating CFV and concentration) beyond which slight or no further increase in steady-state J(p) was observed. Similarly, the higher the CFV was, the more slightly the steady-state J(p) increased. Furthermore, the effectiveness of ultrafiltration treatment was evaluated through dye rejection coefficient. The results showed significant dye removals, regardless of the tested conditions, with steady-state R higher than 79.8% for the 50mg/L runs and around 73.2% for the 500 mg/L runs. Finally response surface methodology (RSM) was used to optimize membrane performance. At 50mg/L, a TMP of 4 bar and a CFV of 2.53 m/s were found to be the conditions giving the highest steady-state J(p), 255.86 L/(m(2)h), and the highest R, 95.2% simultaneously. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Performance of Hollow Fiber Ultrafiltration Membranes in the Clarification of Blood Orange Juice

    Directory of Open Access Journals (Sweden)

    Carmela Conidi

    2015-12-01

    Full Text Available The clarification of blood orange juice by ultrafiltration (UF was investigated by using three hollow fiber membrane modules characterized by different membrane materials (polysulfone (PS and polyacrylonitrile (PAN and molecular weight cut-off (MWCO (50 and 100 kDa. The performance of selected membranes was investigated in terms of productivity and selectivity towards total anthocyanin content (TAC, total phenolic content (TPC, and total antioxidant activity (TAA. All selected membranes allowed a good preservation of antioxidant compounds; however, the most suitable membrane for the clarification of the juice was found to be the PS 100 kDa membrane. In optimized operating conditions this membrane exhibited steady-state fluxes of 7.12 L/m2h, higher than those measured for other investigated membranes. Rejections towards TPC and TAA were of the order of 17.5% and 15%, respectively. These values were lower than those determined for PS 50 kDa and PAN 50 kDa membranes. In addition, the PS 100 kDa membrane exhibited a lower rejection (7.3% towards TAC when compared to the PS 50 kDa membrane (9.2%.

  4. Application of Fe(II)/peroxymonosulfate for improving ultrafiltration membrane performance in surface water treatment: Comparison with coagulation and ozonation.

    Science.gov (United States)

    Cheng, Xiaoxiang; Liang, Heng; Ding, An; Zhu, Xuewu; Tang, Xiaobin; Gan, Zhendong; Xing, Jiajian; Wu, Daoji; Li, Guibai

    2017-11-01

    Coagulation and ozonation have been widely used as pretreatments for ultrafiltration (UF) membrane in drinking water treatment. While beneficial, coagulation or ozonation alone is unable to both efficiently control membrane fouling and product water quality in many cases. Thus, in this study an emerging alternative of ferrous iron/peroxymonosulfate (Fe(II)/PMS), which can act as both an oxidant and a coagulant was employed prior to UF for treatment of natural surface water, and compared with conventional coagulation and ozonation. The results showed that the Fe(II)/PMS-UF system exhibited the best performance for dissolved organic carbon removal, likely due to the dual functions of coagulation and oxidation in the single process. The fluorescent and UV-absorbing organic components were more susceptible to ozonation than Fe(II)/PMS treatment. Fe(II)/PMS and ozonation pretreatments significantly increased the removal efficiency of atrazine, p-chloronitrobenzene and sulfamethazine by 12-76% and 50-94%, respectively, whereas coagulation exerted a minor influence. The Fe(II)/PMS pretreatment also showed the best performance for the reduction of both reversible and irreversible membrane fouling, and the performance was hardly affected by membrane pore size and surface hydrophobicity. In addition, the characterization of hydraulic irreversible organic foulants confirmed its effectiveness. These results demonstrate the potential advantages of applying Fe(II)/PMS as a pretreatment for UF to simultaneously control membrane fouling and improve the permeate quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Fabrication of TiO{sub 2}-modified polytetrafluoroethylene ultrafiltration membranes via plasma-enhanced surface graft pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Yingjia [School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240 (China); Chi, Lina, E-mail: lnchi@sjtu.edu.cn [School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240 (China); Faculty of Engineering and the Environment, University of Southampton, Southampton SO17 1BJ (United Kingdom); Zhou, Weili; Yu, Zhenjiang [School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240 (China); Zhang, Zhongzhi [College of Chemical Engineering, China University of Petroleum, Beijing 102249 (China); Zhang, Zhenjia [School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240 (China); Jiang, Zheng, E-mail: z.jiang@soton.ac.uk [Faculty of Engineering and the Environment, University of Southampton, Southampton SO17 1BJ (United Kingdom)

    2016-01-01

    Graphical abstract: - Highlights: • Multifunctional TiO{sub 2}/PAA/PTFE ultrafiltration membrane was fabricated via tight coating of TiO{sub 2} functional layer onto the plasma-assisted graft of PAA on PTFE. • The high water flux rate, remarkable enhanced ultrafiltration performance and excellent self-cleaning ability were demonstrated. • The formation of COO−Ti bidentate coordination between TiO{sub 2} and PAA was responsible for the successful coating. - Abstract: Surface hydrophilic modification of polymer ultrafiltration membrane using metal oxide represents an effective yet highly challenging solution to improve water flux and antifouling performance. Via plasma-enhanced graft of poly acryl acid (PAA) prior to coating TiO{sub 2}, we successfully fixed TiO{sub 2} functional thin layer on super hydrophobic polytetrafluoroethylene (PTFE) ultrafiltration (UF) membranes. The characterization results evidenced TiO{sub 2} attached on the PTFE-based UF membranes through the chelating bidentate coordination between surface-grafted carboxyl group and Ti{sup 4+}. The TiO{sub 2} surface modification may greatly reduce the water contact angle from 115.8° of the PTFE membrane to 35.0° without degradation in 30-day continuous filtration operations. The novel TiO{sub 2}/PAA/PTFE membranes also exhibited excellent antifouling and self-cleaning performance due to the intrinsic hydrophilicity and photocatalysis properties of TiO{sub 2}, which was further confirmed by the photo-degradation of MB under Xe lamp irradiation.

  6. Dynamic modeling of ultrafiltration membranes for whey separation processes

    NARCIS (Netherlands)

    Saltik, M.B.; Ozkan, L.; Jacobs, M.; van der Padt, A.

    2017-01-01

    In this paper, we present a control relevant rigorous dynamic model for an ultrafiltration membrane unit in a whey separation process. The model consists of a set of differential algebraic equations and is developed for online model based applications such as model based control and process

  7. Surface Activity of Sulfactin Recovered and Purified from Fermentation Broth Using a Two-Step Ultrafiltration (UF) Process

    International Nuclear Information System (INIS)

    Mohd Hafez Mohd Isa; Frazier, A.R.; Jauregi, P.

    2011-01-01

    B. subtilis under certain types of media and fermentation conditions can produce surfactant, a bio surfactant which belongs to the lipo peptide class. Surfactant has exceptional surfactant activity, and exhibits some interesting biological characteristics such as antibacterial activity, anti tumoral activity against ascites carcinoma cells, and a hypercholesterolaemia activity that inhibits cAMP phosphodiesterase, as well as having anti-HIV properties. A cost effective recovery and purification of surfactant from fermentation broth using a two-step ultrafiltration (UF) process has been developed in order to reduce the cost of surfactant production. In this study, competitive adsorption of surfactant and proteins at the air-water interface was studied using surface pressure measurements. Small volumes of bovine serum albumin (BSA) and β-casein solutions were added to the air-water interface on a Langmuir trough and allowed to stabilise before the addition of surfactant to the sub phase. Contrasting interfacial behaviour of proteins was observed with β-casein showing faster initial adsorption compared to BSA. On introduction of surfactant both proteins were displaced but a longer time were taken to displace β-casein. Overall the results showed surfactant were highly surface-active by forming a β-sheet structure at the air-water interface after reaching its critical micelle concentration (CMC) and were effective in removing both protein films, which can be explained following the orogenic mechanism. Results showed that the two-step UF process was effective to achieve high purity and fully functional surfactant. (author)

  8. Enhanced antimony(V) removal using synergistic effects of Fe hydrolytic flocs and ultrafiltration membrane with sludge discharge evaluation.

    Science.gov (United States)

    Ma, Baiwen; Wang, Xing; Liu, Ruiping; Qi, Zenglu; Jefferson, William A; Lan, Huachun; Liu, Huijuan; Qu, Jiuhui

    2017-09-15

    The integration of adsorbents with ultrafiltration (UF) membranes is a promising method for alleviating membrane fouling and reducing land use. However, a number of problems have become apparent concerning the granular adsorbents used currently, such as high running cost, high chance of causing membrane surface damage, low in situ chemical cleaning efficiency, etc. Herein, to overcome these disadvantages, loose in situ hydrolyzed flocs were directly injected into the membrane tank, providing strong adsorption ability at low cost. To test the feasibility of this method, the heavy metal pollutant antimony (Sb (V)) in a water plant was chosen at a test case, which is similar to arsenic and difficult to remove. We found that Fe-based flocs integrated with an UF membrane showed a large potential advantage in removing Sb(V), even after running for 110 days. We demonstrated that the observed slow transmembrane pressure development could be ascribed to the loose floc cake layer formed, even though some extracellular polymeric substances were induced during operation. We also found that the floc cake layer was easily removed by washing with feed water or dissolved by in situ chemical cleaning under strongly acidic conditions, and many primary membrane pores were clearly observed. In addition, a relative long sludge discharge interval was feasible for this technology and the effluent quality was good, including the turbidity, chromaticity and iron concentration. Based on the excellent performance, these flocs integrated with UF membranes indeed show potential for application in water treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Enzymatic treatment for controlling irreversible membrane fouling in cross-flow humic acid-fed ultrafiltration

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Chien-Hwa [Department of Civil and Environment Engineering, Nanya Institute of Technology, Taoyuan, Taiwan (China); Fang, Lung-Chen; Lateef, Shaik Khaja [Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Taiwan (China); Wu, Chung-Hsin, E-mail: chunghsinwu@yahoo.com.tw [Department of Chemical and Materials Engineering, National Kaohsiung University of Applied Sciences, 415 Chien Kung Road, Kaohsiung 807, Taiwan (China); Lin, Cheng-Fang [Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Taiwan (China)

    2010-05-15

    Exploring reasonable ways to remove foulant is of great importance in order to allow sustainable operation of ultrafiltration (UF) membranes in water/wastewater treatment technology. Compounds of organic and inorganic origin largely contribute to irreversible fouling. This study attempted to remove problem of UF membrane fouling by using four different enzymes including {alpha}-amylase, lipase, cellulase and protease. This investigation showed that none of the above mentioned enzymes was found to be effective for the removal of foulant when used alone. However, when these enzymes were used in combination with NaOH and citric acid, about 90% cleaning was achieved. The addition of non-ionic surfactant to the enzymatic solution appears to increase the efficiency of flux recovery by reducing the adhesion of foulant species to the membrane surface through the decrease of contact angle. Field emission gun scanning electron microscopy, Fourier transform infrared spectroscopy and atomic force microscopy (AFM) techniques were employed to qualitatively illustrate the foulant characteristics. The surface roughness through AFM was used to explain the potential mechanism for the enzymatic cleaning.

  10. Enzymatic treatment for controlling irreversible membrane fouling in cross-flow humic acid-fed ultrafiltration

    International Nuclear Information System (INIS)

    Yu, Chien-Hwa; Fang, Lung-Chen; Lateef, Shaik Khaja; Wu, Chung-Hsin; Lin, Cheng-Fang

    2010-01-01

    Exploring reasonable ways to remove foulant is of great importance in order to allow sustainable operation of ultrafiltration (UF) membranes in water/wastewater treatment technology. Compounds of organic and inorganic origin largely contribute to irreversible fouling. This study attempted to remove problem of UF membrane fouling by using four different enzymes including α-amylase, lipase, cellulase and protease. This investigation showed that none of the above mentioned enzymes was found to be effective for the removal of foulant when used alone. However, when these enzymes were used in combination with NaOH and citric acid, about 90% cleaning was achieved. The addition of non-ionic surfactant to the enzymatic solution appears to increase the efficiency of flux recovery by reducing the adhesion of foulant species to the membrane surface through the decrease of contact angle. Field emission gun scanning electron microscopy, Fourier transform infrared spectroscopy and atomic force microscopy (AFM) techniques were employed to qualitatively illustrate the foulant characteristics. The surface roughness through AFM was used to explain the potential mechanism for the enzymatic cleaning.

  11. Contribution of different effluent organic matter fractions to membrane fouling in ultrafiltration of treated domestic wastewater

    KAUST Repository

    Zheng, Xing; Croue, Jean-Philippe

    2012-01-01

    In the present work, effluent organic matter (EfOM) in treated domestic wastewater was separated into hydrophobic neutrals, colloids, hydrophobic acids, transphilic acids and neutrals and hydrophilic compounds. Their contribution to dissolved organic carbon (DOC) was identified. Further characterization was conducted with respect to molecular size and hydrophobicity. Each isolated fraction was dosed into salt solution to identify its fouling potential in ultrafiltration (UF) using a hydrophilized polyethersulfone membrane. The results show that each kind of EfOM leads to irreversible fouling. At similar delivered DOC load to the membrane, colloids present the highest fouling effect in terms of both reversible and irreversible fouling. The hydrophobic organics show much lower reversibility than the biopolymers present. However, as they are of much smaller size than the membrane pore opening, they cannot lead to such severe fouling as biopolymers do. In all of the isolated fractions, hydrophilics show the lowest fouling potential. For either colloids or hydrophobic substances, increasing their content in feedwater leads to worse fouling. The co-effect between biopolymers and other EfOM fractions has also been identified as one of the mechanisms contributing to UF fouling in filtering EfOM-containing waters. © IWA Publishing 2012.

  12. Contribution of different effluent organic matter fractions to membrane fouling in ultrafiltration of treated domestic wastewater

    KAUST Repository

    Zheng, Xing

    2012-12-01

    In the present work, effluent organic matter (EfOM) in treated domestic wastewater was separated into hydrophobic neutrals, colloids, hydrophobic acids, transphilic acids and neutrals and hydrophilic compounds. Their contribution to dissolved organic carbon (DOC) was identified. Further characterization was conducted with respect to molecular size and hydrophobicity. Each isolated fraction was dosed into salt solution to identify its fouling potential in ultrafiltration (UF) using a hydrophilized polyethersulfone membrane. The results show that each kind of EfOM leads to irreversible fouling. At similar delivered DOC load to the membrane, colloids present the highest fouling effect in terms of both reversible and irreversible fouling. The hydrophobic organics show much lower reversibility than the biopolymers present. However, as they are of much smaller size than the membrane pore opening, they cannot lead to such severe fouling as biopolymers do. In all of the isolated fractions, hydrophilics show the lowest fouling potential. For either colloids or hydrophobic substances, increasing their content in feedwater leads to worse fouling. The co-effect between biopolymers and other EfOM fractions has also been identified as one of the mechanisms contributing to UF fouling in filtering EfOM-containing waters. © IWA Publishing 2012.

  13. Fabrication of TiO2-modified polytetrafluoroethylene ultrafiltration membranes via plasma-enhanced surface graft pretreatment

    Science.gov (United States)

    Qian, Yingjia; Chi, Lina; Zhou, Weili; Yu, Zhenjiang; Zhang, Zhongzhi; Zhang, Zhenjia; Jiang, Zheng

    2016-01-01

    Surface hydrophilic modification of polymer ultrafiltration membrane using metal oxide represents an effective yet highly challenging solution to improve water flux and antifouling performance. Via plasma-enhanced graft of poly acryl acid (PAA) prior to coating TiO2, we successfully fixed TiO2 functional thin layer on super hydrophobic polytetrafluoroethylene (PTFE) ultrafiltration (UF) membranes. The characterization results evidenced TiO2 attached on the PTFE-based UF membranes through the chelating bidentate coordination between surface-grafted carboxyl group and Ti4+. The TiO2 surface modification may greatly reduce the water contact angle from 115.8° of the PTFE membrane to 35.0° without degradation in 30-day continuous filtration operations. The novel TiO2/PAA/PTFE membranes also exhibited excellent antifouling and self-cleaning performance due to the intrinsic hydrophilicity and photocatalysis properties of TiO2, which was further confirmed by the photo-degradation of MB under Xe lamp irradiation.

  14. Removal of radionuclides in drinking water by membrane treatment using ultrafiltration, reverse osmosis and electrodialysis reversal

    International Nuclear Information System (INIS)

    Montaña, M.; Camacho, A.; Serrano, I.; Devesa, R.; Matia, L.; Vallés, I.

    2013-01-01

    A pilot plant had been built to test the behaviour of ultrafiltration (UF), reverse osmosis (RO), and electrodialysis reversal (EDR) in order to improve the quality of the water supplied to Barcelona metropolitan area from the Llobregat River. This paper presents results from two studies to reduce natural radioactivity. The results from the pilot plant with four different scenarios were used to design the full-scale treatment plant built (SJD WTP). The samples taken at different steps of the treatment were analysed to determine gross alpha, gross beta and uranium activity. The results obtained revealed a significant improvement in the radiological water quality provided by both membrane techniques (RO and EDR showed removal rates higher than 60%). However, UF did not show any significant removal capacity for gross alpha, gross beta or uranium activities. RO was better at reducing the radiological parameters studied and this treatment was selected and applied at the full scale treatment plant. The RO treatment used at the SJD WTP reduced the concentration of both gross alpha and gross beta activities and also produced water of high quality with an average removal of 95% for gross alpha activity and almost 93% for gross beta activity at the treatment plant. -- Highlights: ► A study with a pilot plant using different membranes technologies was made. ► Big reduction on natural uranium and 40 K by reverse osmosis was found. ► Pilot plant and full-scale treatment plant behave similarly

  15. Investigation of severe UF membrane fouling induced by three marine algal species

    KAUST Repository

    Merle, Tony

    2016-02-06

    Reducing membrane fouling caused by seawater algal bloom is a challenge for regions of the world where most of their freshwater is produced by seawater desalination. This study aims to compare ultrafiltration (UF) fouling potential of three ubiquitous marine algal species cultures (i.e., Skeletonena costatum-SKC, Tetraselmis sp.-TET, and Hymenomonas sp.-HYM) sampled at different phases of growth. Results showed that flux reduction and irreversible fouling were more severe during the decline phase as compared to the exponential phase, for all species. SKC and TET were responsible for substantial irreversible fouling but their impact was significantly lower than HYM. The development of a transparent gel layer surrounding the cell during the HYM growth and accumulating in water is certainly responsible for the more severe observed fouling. Chemical backwash with a standard chlorine solution did not recover any membrane permeability. For TET and HYM, the Hydraulically Irreversible Fouling Index (HIFI) was correlated to their biopolymer content but this correlation is specific for each species. Solution pre-filtration through a 1.2 μm membrane proved that cells and particulate algal organic matter (p-AOM) considerably contribute to fouling, especially for HYM for which the HIFI was reduced by a factor of 82.3.

  16. Nanofiltration and Tight Ultrafiltration Membranes for Natural Organic Matter Removal-Contribution of Fouling and Concentration Polarization to Filtration Resistance.

    Science.gov (United States)

    Winter, Joerg; Barbeau, Benoit; Bérubé, Pierre

    2017-07-02

    Nanofiltration (NF) and tight ultrafiltration (tight UF) membranes are a viable treatment option for high quality drinking water production from sources with high concentrations of contaminants. To date, there is limited knowledge regarding the contribution of concentration polarization (CP) and fouling to the increase in resistance during filtration of natural organic matter (NOM) with NF and tight UF. Filtration tests were conducted with NF and tight UF membranes with molecular weight cut offs (MWCOs) of 300, 2000 and 8000 Da, and model raw waters containing different constituents of NOM. When filtering model raw waters containing high concentrations of polysaccharides (i.e., higher molecular weight NOM), the increase in resistance was dominated by fouling. When filtering model raw waters containing humic substances (i.e., lower molecular weight NOM), the increase in filtration resistance was dominated by CP. The results indicate that low MWCO membranes are better suited for NOM removal, because most of the NOM in surface waters consist mainly of humic substances, which were only effectively rejected by the lower MWCO membranes. However, when humic substances are effectively rejected, CP can become extensive, leading to a significant increase in filtration resistance by the formation of a cake/gel layer at the membrane surface. For this reason, cross-flow operation, which reduces CP, is recommended.

  17. Nanofiltration and Tight Ultrafiltration Membranes for Natural Organic Matter Removal—Contribution of Fouling and Concentration Polarization to Filtration Resistance

    Directory of Open Access Journals (Sweden)

    Joerg Winter

    2017-07-01

    Full Text Available Nanofiltration (NF and tight ultrafiltration (tight UF membranes are a viable treatment option for high quality drinking water production from sources with high concentrations of contaminants. To date, there is limited knowledge regarding the contribution of concentration polarization (CP and fouling to the increase in resistance during filtration of natural organic matter (NOM with NF and tight UF. Filtration tests were conducted with NF and tight UF membranes with molecular weight cut offs (MWCOs of 300, 2000 and 8000 Da, and model raw waters containing different constituents of NOM. When filtering model raw waters containing high concentrations of polysaccharides (i.e., higher molecular weight NOM, the increase in resistance was dominated by fouling. When filtering model raw waters containing humic substances (i.e., lower molecular weight NOM, the increase in filtration resistance was dominated by CP. The results indicate that low MWCO membranes are better suited for NOM removal, because most of the NOM in surface waters consist mainly of humic substances, which were only effectively rejected by the lower MWCO membranes. However, when humic substances are effectively rejected, CP can become extensive, leading to a significant increase in filtration resistance by the formation of a cake/gel layer at the membrane surface. For this reason, cross-flow operation, which reduces CP, is recommended.

  18. Preparation and characterization of poly (methyl methacrylate) and sulfonated poly (ether ether ketone) blend ultrafiltration membranes for protein separation applications

    International Nuclear Information System (INIS)

    Arthanareeswaran, G.; Thanikaivelan, P.; Raajenthiren, M.

    2009-01-01

    Poly (methyl methacrylate) (PMMA) and poly (methyl methacrylate)/sulfonated poly (ether ether ketone) (SPEEK) blend membranes were prepared by phase inversion technique in various composition using N,N'-dimethylformamide as solvent. The prepared membranes were characterized in terms of pure water flux, water content, porosity and thermal stability. The addition of SPEEK to the casting solution resulted in membranes with high pure water flux, water content, porosity and slightly low thermal stability. The cross sectional views of the blend membranes under electron microscope confirm the porosity and water flux results. The effect of the addition of SPEEK into the PMMA matrix on the extent of bovine serum albumin (BSA) separation was studied. It was found that the permeate flux increased significantly while the rejection of BSA from aqueous solution reduced moderately during ultrafiltration (UF) process. The effect was attributed to the increase in porosity and charge of the membrane due to the addition of SPEEK into the PMMA blend solution

  19. Hydrophobicity measurements of microfiltration and ultrafiltration membranes.

    NARCIS (Netherlands)

    Keurentjes, J.T.F.; Harbrecht, J.G.; Brinkman, D.; Hanemaaijer, J.H.; Cohen Stuart, M.A.; Riet, van 't K.

    1989-01-01

    A method for the determination of the hydrophobicity of membrane materials is developed. The advantage of this method over existing methods is that it is not influenced by the presence of the pores. A piece of the membrane material is submerged horizontally in a liquid with surface tension L.

  20. Printing-assisted surface modifications of patterned ultrafiltration membranes

    International Nuclear Information System (INIS)

    Wardrip, Nathaniel C.; Dsouza, Melissa; Urgun-Demirtas, Meltem; Snyder, Seth W.

    2016-01-01

    Understanding and restricting microbial surface attachment will enhance wastewater treatment with membranes. We report a maskless lithographic patterning technique for the generation of patterned polymer coatings on ultrafiltration membranes. Polyethylene glycol, zwitterionic, or negatively charged hydrophilic polymer compositions in parallel- or perpendicular-striped patterns with respect to feed flow were evaluated using wastewater. Membrane fouling was dependent on the orientation and chemical composition of the coatings. Modifications reduced alpha diversity in the attached microbial community (Shannon indices decreased from 2.63 to 1.89) which nevertheless increased with filtration time. Sphingomonas species, which condition membrane surfaces and facilitate cellular adhesion, were depleted in all modified membranes. Microbial community structure was significantly different between control, different patterns, and different chemistries. Lastly, this study broadens the tools for surface modification of membranes with polymer coatings and for understanding and optimization of antifouling surfaces.

  1. Membrane flux dynamics in the submerged ultrafiltration hybrid treatment process during particle and natural organic matter removal

    Institute of Scientific and Technical Information of China (English)

    Wei Zhang; Xiaojian Zhang; Yonghong Li; Jun Wang; Chao Chen

    2011-01-01

    Particles and natural organic matter (NOM) are two major concerns in surface water,which greatly influence the membrane filtration process.The objective of this article is to investigate the effect of particles,NOM and their interaction on the submerged ultrafiltration (UF) membrane flux under conditions of solo UF and coagulation and PAC adsorption as the pretreatment of UF.Particles,NOM and their mixture were spiked in tap water to simulate raw water.Exponential relationship,(JP/JP0 =axexp{-k[t-(n- 1)T]}),was developed to quantify the normalized membrane flux dynamics during the filtration period and fitted the results well.In this equation,coefficient a was determined by the value of Jp/Jp0 at the beginning of a filtration cycle,reflecting the flux recovery after backwashing,that is,the irreversible fouling.The coefficient k reflected the trend of flux dynamics.Integrated total permeability (ΣJp) in one filtration period could be used as a quantified indicator for comparison of different hybrid membrane processes or under different scenarios.According to the results,there was an additive effect on membrane flux by NOM and particles during solo UF process.This additive fouling could be alleviated by coagulation pretreatment since particles helped the formation of flocs with coagulant,which further delayed the decrease of membrane flux and benefited flux recovery by backwashing.The addition of PAC also increased membrane flux by adsorbing NOM and improved flux recovery through backwashing.

  2. Combined effects of coagulation and adsorption on ultrafiltration membrane fouling control and subsequent disinfection in drinking water treatment.

    Science.gov (United States)

    Xing, Jiajian; Liang, Heng; Cheng, Xiaoxiang; Yang, Haiyan; Xu, Daliang; Gan, Zhendong; Luo, Xinsheng; Zhu, Xuewu; Li, Guibai

    2018-06-02

    This study investigated the combined effects of coagulation and powdered activated carbon (PAC) adsorption on ultrafiltration (UF) membrane fouling control and subsequent disinfection efficiency through filtration performance, dissolved organic carbon (DOC) removal, fluorescence excitation-emission matrix (EEM) spectroscopy, and disinfectant curve. The fouling behavior of UF membrane was comprehensively analyzed especially in terms of pollutant removal and fouling reversibility to understand the mechanism of fouling accumulation and disinfectant dose reduction. Pre-coagulation with or without adsorption both achieved remarkable effect of fouling mitigation and disinfection dose reduction. The two pretreatments were effective in total fouling control and pre-coagulation combined with PAC adsorption even decreased hydraulically irreversible fouling notably. Besides, pre-coagulation decreased residual disinfectant decline due to the removal of hydrophobic components of natural organic matters (NOM). Pre-coagulation combined with adsorption had a synergistic effect on further disinfectant decline rate reduction and decreased total disinfectant consumption due to additional removal of hydrophilic NOM by PAC adsorption. The disinfectant demand was further reduced after membrane. These results show that membrane fouling and disinfectant dose can be reduced in UF coupled with pretreatment, which could lead to the avoidance of excessive operation cost disinfectant dose for drinking water supply.

  3. Removal of radionuclides in drinking water by membrane treatment using ultrafiltration, reverse osmosis and electrodialysis reversal.

    Science.gov (United States)

    Montaña, M; Camacho, A; Serrano, I; Devesa, R; Matia, L; Vallés, I

    2013-11-01

    A pilot plant had been built to test the behaviour of ultrafiltration (UF), reverse osmosis (RO), and electrodialysis reversal (EDR) in order to improve the quality of the water supplied to Barcelona metropolitan area from the Llobregat River. This paper presents results from two studies to reduce natural radioactivity. The results from the pilot plant with four different scenarios were used to design the full-scale treatment plant built (SJD WTP). The samples taken at different steps of the treatment were analysed to determine gross alpha, gross beta and uranium activity. The results obtained revealed a significant improvement in the radiological water quality provided by both membrane techniques (RO and EDR showed removal rates higher than 60%). However, UF did not show any significant removal capacity for gross alpha, gross beta or uranium activities. RO was better at reducing the radiological parameters studied and this treatment was selected and applied at the full scale treatment plant. The RO treatment used at the SJD WTP reduced the concentration of both gross alpha and gross beta activities and also produced water of high quality with an average removal of 95% for gross alpha activity and almost 93% for gross beta activity at the treatment plant. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Removal of toxic ions (chromate, arsenate, and perchlorate) using reverse osmosis, nanofiltration, and ultrafiltration membranes

    KAUST Repository

    Yoon, Jaekyung

    2009-09-01

    Rejection characteristics of chromate, arsenate, and perchlorate were examined for one reverse osmosis (RO, LFC-1), two nanofiltration (NF, ESNA, and MX07), and one ultrafiltration (UF and GM) membranes that are commercially available. A bench-scale cross-flow flat-sheet filtration system was employed to determine the toxic ion rejection and the membrane flux. Both model and natural waters were used to prepare chromate, arsenate, and perchlorate solutions (approximately 100 μg L-1 for each anion) in mixtures in the presence of other salts (KCl, K2SO4, and CaCl2); and at varying pH conditions (4, 6, 8, and 10) and solution conductivities (30, 60, and 115 mS m-1). The rejection of target ions by the membranes increases with increasing solution pH due to the increasingly negative membrane charge with synthetic model waters. Cr(VI), As(V), and ClO4 - rejection follows the order LFC-1 (>90%) > MX07 (25-95%) ≅ ESNA (30-90%) > GM (3-47%) at all pH conditions. In contrast, the rejection of target ions by the membranes decreases with increasing solution conductivity due to the decreasingly negative membrane charge. Cr(VI), As(V), and ClO4 - rejection follows the order CaCl2 < KCl ≅ K2SO4 at constant pH and conductivity conditions for the NF and UF membranes tested. For natural waters the LFC-1 RO membrane with a small pore size (0.34 nm) had a significantly greater rejection for those target anions (>90%) excluding NO3 - (71-74%) than the ESNA NF membrane (11-56%) with a relatively large pore size (0.44 nm), indicating that size exclusion is at least partially responsible for the rejection. The ratio of solute radius (ri,s) to effective membrane pore radius (rp) was employed to compare ion rejection. For all of the ions, the rejection is higher than 70% when the ri,s/rp ratio is greater than 0.4 for the LFC-1 membrane, while for di-valent ions (CrO4 2 -, SO4 2 -, and HAsSO4 2 -) the rejection (38-56%) is fairly proportional to the ri,s/rp ratio (0.32-0.62) for the ESNA

  5. Ultrafiltration and nanofiltration membrane fouling by natural organic matter: Mechanisms and mitigation by pre-ozonation and pH.

    Science.gov (United States)

    Yu, Wenzheng; Liu, Teng; Crawshaw, John; Liu, Ting; Graham, Nigel

    2018-08-01

    The fouling of ultrafiltration (UF) and nanofiltration (NF) membranes during the treatment of surface waters continues to be of concern and the particular role of natural organic matter (NOM) requires further investigation. In this study the effect of pH and surface charge on membrane fouling during the treatment of samples of a representative surface water (Hyde Park recreational lake) were evaluated, together with the impact of pre-ozonation. While biopolymers in the surface water could be removed by the UF membrane, smaller molecular weight (MW) fractions of NOM were poorly removed, confirming the importance of membrane pore size. For NF membranes the removal of smaller MW fractions (800 Da-10 kDa) was less than expected from their pore size; however, nearly all of the hydrophobic, humic-type substances could be removed by the hydrophilic NF membranes for all MW distributions (greater than 90%). The results indicated the importance of the charge and hydrophilic nature of the NOM. Thus, the hydrophilic NF membrane could remove the hydrophobic organic matter, but not the hydrophilic substances. Increasing charge effects (more negative zeta potentials) with increasing solution pH were found to enhance organics removal and reduce fouling (flux decline), most likely through greater membrane surface repulsion. Pre-ozonation of the surface water increased the hydrophilic fraction and anionic charge of NOM and altered their size distributions. This resulted in a decreased fouling (less flux decline) for the UF and smaller pore NF, but a slight increase in fouling for the larger pore NF. The differences in the NF behavior are believed to relate to the relative sizes of ozonated organic fractions and the NF pores; a similar size of ozonated organic fractions and the NF pores causes significant membrane fouling. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Low fouling polysulfone ultrafiltration membrane via click chemistry

    KAUST Repository

    Xie, Yihui

    2014-10-13

    Hydrophilic surfaces are known to be less prone to fouling. Ultrafiltration membranes are frequently prepared from rather hydrophobic polymers like polysulfone (PSU). Strategies to keep the good pore forming characteristics of PSU, but with improved hydrophilicity are proposed here. PSU functionalized with 1,2,3-triazole ring substituents containing OH groups was successfully synthesized through click chemistry reaction. The structures of the polymers were confirmed using NMR spectroscopy and Fourier transform infrared spectroscopy (FTIR). High thermal stability (>280°C) was observed by thermal gravimetric analysis. Elemental analysis showed the presence of nitrogen containing triazole group with different degrees of functionalization (23%, 49%, 56%, and 94%). The glass transition temperature shifted with the introduction of triazole pendant groups from 190°C (unmodified) to 171°C. Ultrafiltration membranes were prepared via phase inversion by immersion in different coagulation baths (NMP/water mixtures with volume ratios from 0/100 to 40/60). The morphologies of these membranes were studied by field emission scanning electron microscopy (FESEM). The optimized PSU bearing triazole functions membranes exhibited water permeability up to 187 L m-2 h-1 bar-1, which is 23 times higher than those prepared under the same conditions but with unmodified polysulfone (PSU; 8 L m-2 h-1 bar-1). Results of bovine serum albumin protein rejection test indicated that susceptibility to fouling decreased with the modification, due to the increased hydrophilicity, while keeping high protein rejection ratio (>99%).

  7. Influence of hydraulic retention time on UASB post-treatment with UF membranes.

    Science.gov (United States)

    Salazar-Peláez, M L; Morgan-Sagastume, J M; Noyola, A

    2011-01-01

    A pilot UASB reactor coupled with an external ultrafiltration (UF) membrane was operated under three different hydraulic retention times (HRT) for domestic wastewater treatment. The aim was to assess the HRT influence on system performance and fouling. The highest concentrations of COD, total solids, extracellular polymeric substances (EPS) and soluble microbial products (SMP) in UASB effluent and permeate were found when the UASB reactor was operated under the lowest HRT studied (4 hours); although the fulfillment of Mexican Standard for wastewater reclamation was not compromised. This fact could be attributed to the higher shear stress forces inside the UASB reactor when it was operated at low HRT, which promoted the release of biopolymeric substances in its effluent. Besides, the fouling propensity in the UASB effluent was worsened with HRT reduction, by increasing the fouling rate and the specific cake resistance. Based on these results, it is recommended to avoid operating the UASB reactor at low HRTs (less than 4 hours) in order to control SMP and EPS fouling potential. The results presented also suggest that HRT reduction has a detrimental effect on performance and fouling.

  8. Nanofiltration and Tight Ultrafiltration Membranes for the Recovery of Polyphenols from Agro-Food By-Products

    Directory of Open Access Journals (Sweden)

    Alfredo Cassano

    2018-01-01

    Full Text Available Pressure-driven membrane-based technologies represent a valid approach to reduce the environmental pollution of several agro-food by-products. Recently, in relation to the major interest for natural compounds with biological activities, their use has been also addressed to the recovery, separation and fractionation of phenolic compounds from such by-products. In particular, tight ultrafiltration (UF and nanolfiltration (NF membranes have been recognized for their capability to recover phenolic compounds from several types of agro-food by-products. The separation capability of these membranes, as well as their productivity, depends on multiple factors such as membrane material, molecular weight cut-off (MWCO and operating conditions (e.g., pressure, temperature, feed flow rate, volume reduction factor, etc.. This paper aims at providing a critical overview of the influence of these parameters on the recovery of phenolic compounds from agro-food by-products by using tight UF and NF membranes. The literature data are analyzed and discussed in relation to separation processes, molecule properties, membrane characteristics and other phenomena occurring in the process. Current extraction methodologies of phenolic compounds from raw materials are also introduced in order to drive the implementation of integrated systems for the production of actractive phenolic formulations of potential interest as food antioxidants.

  9. Nanofiltration and Tight Ultrafiltration Membranes for the Recovery of Polyphenols from Agro-Food By-Products.

    Science.gov (United States)

    Cassano, Alfredo; Conidi, Carmela; Ruby-Figueroa, René; Castro-Muñoz, Roberto

    2018-01-24

    Pressure-driven membrane-based technologies represent a valid approach to reduce the environmental pollution of several agro-food by-products. Recently, in relation to the major interest for natural compounds with biological activities, their use has been also addressed to the recovery, separation and fractionation of phenolic compounds from such by-products. In particular, tight ultrafiltration (UF) and nanolfiltration (NF) membranes have been recognized for their capability to recover phenolic compounds from several types of agro-food by-products. The separation capability of these membranes, as well as their productivity, depends on multiple factors such as membrane material, molecular weight cut-off (MWCO) and operating conditions (e.g., pressure, temperature, feed flow rate, volume reduction factor, etc.). This paper aims at providing a critical overview of the influence of these parameters on the recovery of phenolic compounds from agro-food by-products by using tight UF and NF membranes. The literature data are analyzed and discussed in relation to separation processes, molecule properties, membrane characteristics and other phenomena occurring in the process. Current extraction methodologies of phenolic compounds from raw materials are also introduced in order to drive the implementation of integrated systems for the production of actractive phenolic formulations of potential interest as food antioxidants.

  10. The effect of protein-protein and protein-membrane interactions on membrane fouling in ultrafiltration

    NARCIS (Netherlands)

    Huisman, I.H.; Prádanos, P.; Hernández, A.

    2000-01-01

    It was studied how protein-protein and protein-membrane interactions influence the filtration performance during the ultrafiltration of protein solutions over polymeric membranes. This was done by measuring flux, streaming potential, and protein transmission during filtration of bovine serum albumin

  11. Modeling of Hollow-Fiber Membrane System During Ultrafiltration

    International Nuclear Information System (INIS)

    EI-Bialy, S.H.

    2004-01-01

    The present study aims to evaluate the performance of hollow fiber membrane module during ultrafiltration of aqueous solutions. The model is represented by a set of differential equations for permeate and residue pressure drop and volumetric flow rates in the axial direction, beside the principle equations of both solvent and solute fluxes through the membrane, while osmotic pressure was neglected in model equations. The shell and tube module type was considered where feed pass in the shell and permeate in the bore side. Tortousily factor of membrane pores in addition to concentration polarization modulus were taken into account in calculations. The model was solved numerically with the help of suitable program in both co current and countercurrent flow pattern and comparison of results were carried out

  12. Influence of photo-induced superhydrophilicity of titanium dioxide nanoparticles on the anti-fouling performance of ultrafiltration membranes

    Energy Technology Data Exchange (ETDEWEB)

    Madaeni, S.S., E-mail: smadaeni@yahoo.com [Membrane Research Center, Department of Chemical Engineering, Razi University, Tagh Bostan, 67149 Kermanshah (Iran, Islamic Republic of); Ghaemi, N. [Membrane Research Center, Department of Chemical Engineering, Razi University, Tagh Bostan, 67149 Kermanshah (Iran, Islamic Republic of); Department of Chemical Engineering, Kermanshah University of Technology, Kermanshah (Iran, Islamic Republic of); Alizadeh, A. [Nanoscience and Nanotechnology Research Centre (NNRC), Faculty of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of); Joshaghani, M. [Faculty of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of)

    2011-05-01

    Fouling is one of the most present prominent problems in almost all membrane processes. An increase in the membrane hydrophilicity is one of the effective ways to improve the membrane resistance to fouling. In this research, TiO{sub 2} nanoparticles were deposited on the surface of composite ultrafiltration (UF) membrane, and then irradiated by ultraviolet (UV) light. The coating of the membrane surface with TiO{sub 2} nanoparticles and radiation with (UV) light led to the considerable increase of hydrophilicity on the membrane surface. The deposition of TiO{sub 2} nanoparticles was carried out through coordinance bonds with OH functional groups of the polymer on the membrane surface. The flux through a coated and (UV) light radiated membrane was increased to a large extent compared to a virgin membrane. In this research, the effect of different concentrations of TiO{sub 2} nanoparticles in the presence and absence of (UV) irradiation was investigated, and the role of increasing of hydrophilicity on the anti-fouling property of membranes was studied. In order to characterize the membranes FTIR, XRD, SEM, water contact angle and cross-flow filtration were employed. This procedure is a useful technique for improvement of hydrophilicity to decrease (increase) fouling (anti-fouling performance) and enhance the permeation of membranes.

  13. A synergetic analysis method for antifouling behavior investigation on PES ultrafiltration membrane with self-assembled TiO2 nanoparticles.

    Science.gov (United States)

    Li, Xin; Li, Jiansheng; Fang, Xiaofeng; Bakzhan, Kariboz; Wang, Lianjun; Van der Bruggen, Bart

    2016-05-01

    Fouling of ultrafiltration (UF) membranes is a major impediment for their use in drinking water production. Mixed matrix membranes (MMMs) may have great opportunities in dealing with this challenge due to their hierarchical structures and multiple functionalities. In this study, a synergetic analysis method based on intermolecular adhesion force measurement and fouling process simulation was applied to investigate the fouling mechanism of polyethersulfone (PES) UF membranes containing in situ self-assembled TiO2 nanoparticles (NPs). The fouling resistance behavior and antifouling mechanism of the newly developed composite membranes were investigated with sodium alginate (SA), bovine serum albumin (BSA) and humic acid (HA) as model organic foulants. An improved antifouling effect was conspicuously observed for the composite membranes, expressed by a lower flux decline and significantly better cleaning efficiency. A strong correlation between the self-assembled structure of TiO2 NPs and the antifouling behavior of the composite membrane was observed. A lower magnitude and a narrower distribution of adhesion forces for the composite membrane suggest the effective suppression of foulants adsorption on the clean or fouled membrane. The simulation analysis indicates that the main fouling mechanism was standard blocking and cake filtration, further confirming the superiority of the NPs self-assembled structure in mitigating membrane fouling. This dual analysis method may provide a promising technological support for the application of modified UF membranes with self-assembled NPs in drinking water production. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Ultrafiltration and Nanofiltration Multilayer Membranes Based on Cellulose

    KAUST Repository

    Livazovic, Sara

    2016-06-09

    Membrane processes are considered energy-efficient for water desalination and treatment. However most membranes are based on polymers prepared from fossil petrochemical sources. The development of multilayer membranes for nanofiltration and ultrafiltration, with thin selective layers of naturally available cellulose, has been hampered by the availability of non-aggressive solvents. We propose the manufacture of cellulose membranes based on two approaches: (i) silylation, coating from solutions in tetrahydrofuran, followed by solvent evaporation and cellulose regeneration by acid treatment; (ii) casting from solution in 1-ethyl-3-methylimidazolum acetate ([C2mim]OAc), an ionic liquid, followed by phase inversion in water. In the search for less harsh, greener membrane manufacture, the combination of cellulose and ionic liquid is of high interest. Due to the abundance of OH groups and hydrophilicity, cellulose-based membranes have high permeability and low fouling tendency. Membrane fouling is one of the biggest challenges in membrane industry and technology. Accumulation and deposition of foulants onto the surface reduce membrane efficiency and requires harsh chemical cleaning, therefore increasing the cost of maintenance and replacement. In this work the resistance of cellulose 5 membranes towards model organic foulants such as Suwanee River Humic Acid (SRHA) and crude oil have been investigated. Cellulose membrane was tested in this work for oil-water (o/w) separation and exhibited practically 100 % oil rejection with good flux recovery ratio and membrane resistivity. The influence of anionic, cationic and ionic surfactant as well as pH and crude oil concentration on oil separation was investigated, giving a valuable insight in experimental and operational planning.

  15. Protein fouling in carbon nanotubes enhanced ultrafiltration membrane: Fouling mechanism as a function of pH and ionic strength

    KAUST Repository

    Lee, Jieun; Jeong, Sanghyun; Ye, Yun; Chen, Vicki; Vigneswaran, Saravanamuthu; Leiknes, TorOve; Liu, Zongwen

    2016-01-01

    The protein fouling behavior was investigated in the filtration of the multiwall carbon nanotube (MWCNT) composite membrane and commercial polyethersulfone ultrafiltration (PES-UF) membrane. The effect of solution chemistry such as pH and ionic strength on the protein fouling mechanism was systematically examined using filtration model such as complete pore blocking, intermediate pore blocking and cake layer formation. The results showed that the initial permeate flux pattern and fouling behavior of the MWCNT composite membrane were significantly influenced by pH and ionic strength while the effect of PES-UF membrane on flux was minimal. In a lysozyme (Lys) filtration, the severe pore blocking in the MWCNT membrane was made by the combined effect of intra-foulant interaction (Lys-Lys) and electrostatic repulsion between the membrane surface and the foulant at pH 4.7 and 10.4, and increasing ionic strength where the foulant-foulant interaction and membrane-fouling interaction were weak. In a bovine serum albumin (BSA) filtration, severe pore blocking was reduced by less deposition via the electrostatic interaction between the membrane and foulant at pH 4.7 and 10.4 and increasing ionic strength, at which the interaction between the membrane and BSA became weak. For binary mixture filtration, the protein fouling mechanism was more dominantly affected by foulant-foulant interaction (Lys-BSA, Lys-Lys, and BSA-BSA) at pH 7.0 and increase in ionic strength. This research demonstrates that MWCNT membrane fouling can be alleviated by changing pH condition and ionic strength based on the foulant-foulant interaction and the electrostatic interaction between the membrane and foulant.

  16. Protein fouling in carbon nanotubes enhanced ultrafiltration membrane: Fouling mechanism as a function of pH and ionic strength

    KAUST Repository

    Lee, Jieun

    2016-11-04

    The protein fouling behavior was investigated in the filtration of the multiwall carbon nanotube (MWCNT) composite membrane and commercial polyethersulfone ultrafiltration (PES-UF) membrane. The effect of solution chemistry such as pH and ionic strength on the protein fouling mechanism was systematically examined using filtration model such as complete pore blocking, intermediate pore blocking and cake layer formation. The results showed that the initial permeate flux pattern and fouling behavior of the MWCNT composite membrane were significantly influenced by pH and ionic strength while the effect of PES-UF membrane on flux was minimal. In a lysozyme (Lys) filtration, the severe pore blocking in the MWCNT membrane was made by the combined effect of intra-foulant interaction (Lys-Lys) and electrostatic repulsion between the membrane surface and the foulant at pH 4.7 and 10.4, and increasing ionic strength where the foulant-foulant interaction and membrane-fouling interaction were weak. In a bovine serum albumin (BSA) filtration, severe pore blocking was reduced by less deposition via the electrostatic interaction between the membrane and foulant at pH 4.7 and 10.4 and increasing ionic strength, at which the interaction between the membrane and BSA became weak. For binary mixture filtration, the protein fouling mechanism was more dominantly affected by foulant-foulant interaction (Lys-BSA, Lys-Lys, and BSA-BSA) at pH 7.0 and increase in ionic strength. This research demonstrates that MWCNT membrane fouling can be alleviated by changing pH condition and ionic strength based on the foulant-foulant interaction and the electrostatic interaction between the membrane and foulant.

  17. Characterization of anisotropic UF-membranes: top layer thickness and pore structure

    NARCIS (Netherlands)

    Cuperus, F.P.; Cuperus, F.P.; Bargeman, D.; Bargeman, D.; Smolders, C.A.; Smolders, C.A.

    1991-01-01

    Anisotropic poly(2,6-dimethyl-, 1,4-phenylene oxide) (PPO) ultrafiltration membranes are characterized by means of two techniques. A new method for the determination of skin thicknesses, the gold sol method, is introduced and applied to these membranes. The membranes appeared to have a well-defined

  18. Exploring the synergetic effects of graphene oxide (GO) and polyvinylpyrrodione (PVP) on poly(vinylylidenefluoride) (PVDF) ultrafiltration membrane performance

    International Nuclear Information System (INIS)

    Chang, Xiaojing; Wang, Zhenxing; Quan, Shuai; Xu, Yanchao; Jiang, Zaixing; Shao, Lu

    2014-01-01

    Graphical abstract: - Highlights: • The synergetic effects of GO and PVP on membrane performance were investigated. • The surface hydrophilicity of membrane was enhanced by the synergistic effects. • The anti-fouling performance was obviously improved in PVDF/GO/PVP membrane. • The optimized performance can be obtained at the stipulated GO and PVP contents. - Abstract: Membrane surface and cross-sectional morphology created during membrane formation is one of the most essential factors determining membrane separation performance. However, the complicated interactions between added nanoparticles and additives influencing membrane morphology and performance during building membrane architectures had been generally neglected. In this study, asymmetric PVDF composite ultrafiltration (UF) membranes containing graphene oxides (GO) were prepared by using N-methyl pyrrolidone (NMP) as solvent and polyvinylpyrrodione (PVP) as the pore forming reagent. In the first time, the effects of mutual interactions between GO and PVP on membranes surface compositions, morphology and performance were investigated in detail. The variation in chemical properties of different membranes and hydrogen bonds in the membrane containing GO and PVP were confirmed by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR). Atomic force microscopy (AFM), scanning electron microscopy (SEM), and contact angle (CA) were utilized to clarify the synergetic effects of GO and PVP on morphologies and surface hydrophilicity of membranes. Besides, water flux, bovine serum albumin (BSA) rejection and attenuate coefficient were also determined to investigate filtration performance of various membranes. Compared with pure PVDF membrane, the comprehensive performance of PVDF/GO/PVP membrane has been obviously improved. The surface hydrophilicity and anti-fouling performance were enhanced by the synergistic effects of incorporated GO and

  19. Exploring the synergetic effects of graphene oxide (GO) and polyvinylpyrrodione (PVP) on poly(vinylylidenefluoride) (PVDF) ultrafiltration membrane performance

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Xiaojing [State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), School of Chemical Engineering and Technology, Harbin Institute of Technology 150001 (China); Research Institute of Aerospace Special Materials and Technology, Beijing 100074 (China); Wang, Zhenxing; Quan, Shuai; Xu, Yanchao; Jiang, Zaixing [State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), School of Chemical Engineering and Technology, Harbin Institute of Technology 150001 (China); Shao, Lu, E-mail: odysseynus@hotmail.com [State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), School of Chemical Engineering and Technology, Harbin Institute of Technology 150001 (China)

    2014-10-15

    Graphical abstract: - Highlights: • The synergetic effects of GO and PVP on membrane performance were investigated. • The surface hydrophilicity of membrane was enhanced by the synergistic effects. • The anti-fouling performance was obviously improved in PVDF/GO/PVP membrane. • The optimized performance can be obtained at the stipulated GO and PVP contents. - Abstract: Membrane surface and cross-sectional morphology created during membrane formation is one of the most essential factors determining membrane separation performance. However, the complicated interactions between added nanoparticles and additives influencing membrane morphology and performance during building membrane architectures had been generally neglected. In this study, asymmetric PVDF composite ultrafiltration (UF) membranes containing graphene oxides (GO) were prepared by using N-methyl pyrrolidone (NMP) as solvent and polyvinylpyrrodione (PVP) as the pore forming reagent. In the first time, the effects of mutual interactions between GO and PVP on membranes surface compositions, morphology and performance were investigated in detail. The variation in chemical properties of different membranes and hydrogen bonds in the membrane containing GO and PVP were confirmed by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR). Atomic force microscopy (AFM), scanning electron microscopy (SEM), and contact angle (CA) were utilized to clarify the synergetic effects of GO and PVP on morphologies and surface hydrophilicity of membranes. Besides, water flux, bovine serum albumin (BSA) rejection and attenuate coefficient were also determined to investigate filtration performance of various membranes. Compared with pure PVDF membrane, the comprehensive performance of PVDF/GO/PVP membrane has been obviously improved. The surface hydrophilicity and anti-fouling performance were enhanced by the synergistic effects of incorporated GO and

  20. Whey pretreatments before ultrafiltration

    Directory of Open Access Journals (Sweden)

    Tuomo Tupasela

    1994-09-01

    Full Text Available Whey is a by-product of cheesemaking. Whey dry matter contains mainly lactose, but also valuable whey proteins. The aim of this study was to develop improvements to whey protein membrane isolation processes. In our trials CaCl2 -added, pH-adjusted and heat-treated wheys were found to have MF (microfiltration permeate fluxes about 30% higher than in untreated MF whey. The total solids and protein content of the MF permeates decreased compared to the original wheys. UF (ultrafiltration trials were conducted using MF whey to compare it with centrifugally separated whey. The MF whey consistently maintained an UF flux about 1.5 to 2.5 times higher than that of the separated whey. Differently treated MF whey UF permeate fluxes also showed a difference. With CaCl2 addition, pH adjustment and heat treatment, the UF permeate fluxes were about 20 to 40% higher than when only MF was used. The total solids content decreased in each trial. The protein content of the UF concentrate also decreased compared to the MF permeate. The (β-lg (β-lactoglobulin and α-la (α-lactalbumin content was almost the same in UF concentrates as in MF permeates.

  1. Development of Ultrafiltration Membrane-Separation Technology for Energy-Efficient Water Treatment and Desalination Process

    Energy Technology Data Exchange (ETDEWEB)

    Yim, Woosoon [Univ. of Nevada, Las Vegas, NV (United States); Bae, Chulsung [Rensselaer Polytechnic Inst., Troy, NY (United States)

    2016-10-28

    The growing scarcity of fresh water is a major political and economic challenge in the 21st century. Compared to thermal-based distillation technique of water production, pressure driven membrane-based water purification process, such as ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO), can offer more energy-efficient and environmentally friendly solution to clean water production. Potential applications also include removal of hazardous chemicals (i.e., arsenic, pesticides, organics) from water. Although those membrane-separation technologies have been used to produce drinking water from seawater (desalination) and non-traditional water (i.e., municipal wastewater and brackish groundwater) over the last decades, they still have problems in order to be applied in large-scale operations. Currently, a major huddle of membrane-based water purification technology for large-scale commercialization is membrane fouling and its resulting increases in pressure and energy cost of filtration process. Membrane cleaning methods, which can restore the membrane properties to some degree, usually cause irreversible damage to the membranes. Considering that electricity for creating of pressure constitutes a majority of cost (~50%) in membrane-based water purification process, the development of new nano-porous membranes that are more resistant to degradation and less subject to fouling is highly desired. Styrene-ethylene/butylene-styrene (SEBS) block copolymer is one of the best known block copolymers that induces well defined morphologies. Due to the polarity difference of aromatic styrene unit and saturated ethylene/butylene unit, these two polymer chains self-assemble each other and form different phase-separated morphologies depending on the ratios of two polymer chain lengths. Because the surface of SEBS is hydrophobic which easily causes fouling of membrane, incorporation of ionic group (e,g, sulfonate) to the polymer is necessary to reduces fouling

  2. Fouling behavior of poly(ether)sulfone ultrafiltration membrane during concentration of whey proteins: Effect of hydrophilic modification using atmospheric pressure argon jet plasma.

    Science.gov (United States)

    Damar Huner, Irem; Gulec, Haci Ali

    2017-12-01

    The aim of the study was to investigate the effects of hydrophilic surface modification via atmospheric pressure jet plasma (ApJPls) on the fouling propensity of polyethersulfone (PES) ultrafiltration (UF) membranes during concentration of whey proteins. The distance from nozzle to substrate surface of 30mm and the exposure period of 5 times were determined as the most effective parameters enabling an increase in ΔG iwi value of the plain membrane from (-) 14.92±0.89mJ/m 2 to (+) 17.57±0.67mJ/m 2 . Maximum hydrophilicity and minimum surface roughness achieved by argon plasma action resulted in better antifouling behavior, while the hydraulic permeability and the initial permeate flux were decreased sharply due to the plasma-induced surface cross-linking. A quite steady state flux was obtained throughout the UF with the ApJPls modified PES membrane. The contribution of R frev to R t , which was 94% for the UF through the plain membrane, decreased to 43% after the plasma treatment. The overall results of this study highlighted the ApJPls modification decreased the fouling propensity of PES membrane without affecting the original protein rejection capability and improved the recovery of initial permeate flux after chemical cleaning. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Comparison of two treatments for the removal of selected organic micropollutants and bulk organic matter: conventional activated sludge followed by ultrafiltration versus membrane bioreactor.

    Science.gov (United States)

    Sahar, E; Ernst, M; Godehardt, M; Hein, A; Herr, J; Kazner, C; Melin, T; Cikurel, H; Aharoni, A; Messalem, R; Brenner, A; Jekel, M

    2011-01-01

    The potential of membrane bioreactor (MBR) systems to remove organic micropollutants was investigated at different scales, operational conditions, and locations. The effluent quality of the MBR system was compared with that of a plant combining conventional activated sludge (CAS) followed by ultrafiltration (UF). The MBR and CAS-UF systems were operated and tested in parallel. An MBR pilot plant in Israel was operated for over a year at a mixed liquor suspended solids (MLSS) range of 2.8-10.6 g/L. The MBR achieved removal rates comparable to those of a CAS-UF plant at the Tel-Aviv wastewater treatment plant (WWTP) for macrolide antibiotics such as roxythromycin, clarithromycin, and erythromycin and slightly higher removal rates than the CAS-UF for sulfonamides. A laboratory scale MBR unit in Berlin - at an MLSS of 6-9 g/L - showed better removal rates for macrolide antibiotics, trimethoprim, and 5-tolyltriazole compared to the CAS process of the Ruhleben sewage treatment plant (STP) in Berlin when both were fed with identical quality raw wastewater. The Berlin CAS exhibited significantly better benzotriazole removal and slightly better sulfamethoxazole and 4-tolyltriazole removal than its MBR counterpart. Pilot MBR tests (MLSS of 12 g/L) in Aachen, Germany, showed that operating flux significantly affected the resulting membrane fouling rate, but the removal rates of dissolved organic matter and of bisphenol A were not affected.

  4. Effect of biological and coagulation pre-treatments to control organic and biofouling potential components of ultrafiltration membrane in the treatment of lake water.

    Science.gov (United States)

    Pramanik, Biplob Kumar; Kajol, Annaduzzaman; Suja, Fatihah; Md Zain, Shahrom

    2017-03-01

    Biological aerated filter (BAF), sand filtration (SF), alum and Moringa oleifera coagulation were investigated as a pre-treatment for reducing the organic and biofouling potential component of an ultrafiltration (UF) membrane in the treatment of lake water. The carbohydrate content was mainly responsible for reversible fouling of the UF membrane compared to protein or dissolved organic carbon (DOC) content. All pre-treatment could effectively reduce these contents and led to improve the UF filterability. Both BAF and SF markedly led to improvement in flux than coagulation processes, and alum gave greater flux than M. oleifera. This was attributed to the effective removal and/or breakdown of high molecular weight (MW) organics by biofilters. BAF led to greater improvement in flux than SF, due to greater breakdown of high MW organics, and this was also confirmed by the attenuated total reflection-Fourier transform infrared spectroscopy analysis. Coagulation processes were ineffective in removing biofouling potential components, whereas both biofilters were very effective as shown by the reduction of low MW organics, biodegradable dissolved organic carbon and assimilable organic carbon contents. This study demonstrated the potential of biological pre-treatments for reducing organic and biofouling potential component and thus improving flux for the UF of lake water treatment.

  5. Fouling Removal of UF Membrane with Coated TiO2 Nanoparticles under UV Irradiation for Effluent Recovery during TFT-LCD Manufacturing

    Directory of Open Access Journals (Sweden)

    S. H. You

    2013-01-01

    Full Text Available An ultrafiltration (UF membrane process was employed to treat the secondary effluent discharged from a manufacturing of thin film transistor-liquid crystal display (TFT-LCD in this study. A bench-scale system was performed to evaluate the fouling removal of a UF membrane with coated titanium dioxide (TiO2 nanoparticles under UV irradiation. The operating pressure and feed temperature were controlled at 300 KN/m2 and 25°C, respectively. It was found that the optimum operating conditions were attained with TiO2 concentrations of 10 wt% for both 5 KD and 10 KD MWCO. Continuous UV irradiation of 5 KD MWCO improved the permeate flux rate from 45.0% to 59.5% after 4 hours of operation. SEM-EDS analysis also showed that the photocatalytic effect had reduced the average thickness of cake fouling on the membrane from 6.40 μm to 2.70 μm for 5 KD MWCO and from 6.70 μm to 3.1 μm for 10 KD MWCO. In addition, the membrane contact angle was reduced from 54° to 44°. The photocatalytic properties of TiO2 apparently increased the hydrophilicity of the membrane surface, thereby reducing membrane fouling.

  6. Influence of fertilizer draw solution properties on the process performance and microbial community structure in a side-stream anaerobic fertilizer-drawn forward osmosis – ultrafiltration bioreactor

    KAUST Repository

    Kim, Youngjin; Li, Sheng; Chekli, Laura; Phuntsho, Sherub; Ghaffour, NorEddine; Leiknes, TorOve; Shon, Ho Kyong

    2017-01-01

    In this study, a side-stream anaerobic fertilizer-drawn forward osmosis (FDFO) and ultrafiltration (UF) membrane bioreactor (MBR) hybrid system was proposed and operated for 55 days. The FDFO performance was first investigated in terms of flux

  7. Mass transfer in corrugated-plate membrane modules. II. Ultrafiltration experiments

    NARCIS (Netherlands)

    van der Waal, M.J.; Stevanovic, S.; Racz, I.G.

    1989-01-01

    The application of corrugations as turbulence promoters in membrane filtration was studied. In ultrafiltration experiments with polysulfone membranes using Dextran T70 as solute, it was found that the corrugations result in reduced energy consumption or pressure drop compared with flat membranes at

  8. Recovery of Fermented Spinach (Amaranthus sp. Concentrate Through Ultrafiltration Membrane Process as Source of Folic Acid for Smart Food Formula

    Directory of Open Access Journals (Sweden)

    Aspiyanto Aspiyanto

    2017-11-01

    Full Text Available Fermentation process on spinach (Amaranthus sp. by Kombucha culture was done as an effort to recover naturally folic acid as bioactive components to increase smartness. The experimental activity was done by means of UF membrane (100,000 MWCO fitted in Stirred Ultrafiltration Cell (SUFC at stirrer rotation speed 200 and 400 rpm, room temperature, pressure 20 and 40 Psi for 30 min. Result of experimental activity showed that based on both selectivity and recovery of folic acid, process optimization of UF was reached at stirrer rotation speed 200 rpm and pressure 40 Psi. In the optimum condition, SUFC technique was able to recover folic acid in retentate 67.75% and in permeate 97.27% (63.19 µg/mL. Identification of monomer in permeate from the optimum process treatment was find out folic acid monomer with molecular weight (MW 441.39 and relative intensity 93% at mass spectra T2.32 between m/z 257–304 and glutamic acids monomer with MW 148.57 and relative intensity 0.22% at mass spectra T2.82 between m/z 415–470. Other dominant monomer were folic acid fraction.

  9. Moderate KMnO4-Fe(II) pre-oxidation for alleviating ultrafiltration membrane fouling by algae during drinking water treatment.

    Science.gov (United States)

    Ma, Baiwen; Qi, Jing; Wang, Xing; Ma, Min; Miao, Shiyu; Li, Wenjiang; Liu, Ruiping; Liu, Huijuan; Qu, Jiuhui

    2018-05-21

    Although ultrafiltration (UF) membranes are highly beneficial for removing algae, the removal process causes serious UF membrane fouling. To avoid the unfavorable effects of algal cells that have been damaged by oxidants, our previous study reported a novel, moderate pre-oxidation method (KMnO 4 -Fe(II) process) that aimed to achieve a balance between the release of intracellular organic matter and enhanced algae removal. This study further investigated the performance of a UF membrane with KMnO 4 -Fe(II) pretreatment in the presence of algae-laden reservoir water after a long running time. We found that algae could be completely removed, membrane fouling was significantly alleviated, and the overall performance was much better than that of Fe(III) coagulation alone. The transmembrane pressure (TMP) during Fe(III) coagulation increased to 42.8 kPa, however, that of the KMnO 4 -Fe(II) process only increased to 25.1 kPa for after running for 90 d. The slower transmembrane pressure was attributed to the larger floc size, higher surface activity, and inactivation of algae. Although there was little effect on microorganism development, lower microorganism abundance (20.7%) was observed during the KMnO 4 -Fe(II) process than during coagulation alone (44.9%) due to the release of extracellular polymeric substances. We also found that the floc cake layer was easily removed by washing, and many of the original membrane pores were clearly observed. Further analysis demonstrated that the effluent quality was excellent, especially its turbidity, chromaticity, and Mn and Fe concentrations. Based on the outstanding UF membrane performance, it may be concluded that the KMnO 4 -Fe(II) process exhibits considerable potential for application in the treatment of algae-laden water. Copyright © 2018. Published by Elsevier Ltd.

  10. The Effect of Cellulose Acetate Concentration from Coconut Nira on Ultrafiltration Membrane Characters

    Science.gov (United States)

    Vaulina, E.; Widyaningsih, S.; Kartika, D.; Romdoni, M. P.

    2018-04-01

    Cellulose acetate is one of material in produce ultrafiltration membrane. Many efforts have been done to produce cellulose acetate from natural product to replace commercial one. In this research, ultrafiltration membrane has been produced from coconut flower water (nira). Ultrafiltration membrane is widely used in separation processes. This research aims to determine the characteristics of ultrafiltration membrane at a various concentration of cellulose acetate. The ultrafiltration membrane is conducted by phase inversion method at various concentration of cellulose acetate. The cellulose acetate concentration was 20%, 23% and 25% (w/w) with formamide as additives. The results showed that the greater the concentration of cellulose acetate, the smaller the flux value. The highest flux was a membrane with 20% cellulose acetate concentration with water flux value 55.34 L/(m2. h). But the greater the concentration of cellulose acetate the greater the rejection. The highest rejection value was on a membrane with 25% cellulose acetate concentration of 82.82%. While from the tensile strength test and the pore size analysis, the greater the cellulose acetate concentration the greater the tensile strength and the smaller the pore size

  11. The importance of pretreatment tailoring on the performance of ultrafiltration membranes to treat two-phase olive mill wastewater

    Directory of Open Access Journals (Sweden)

    Ochando Pulido, J. M.

    2015-03-01

    Full Text Available In this work, the performance of an ultrafiltration (UF membrane in the treatment of the effluents by-produced by olive mills is addressed by applying different pretreatments on the raw effluents. By conducting a photo-catalytic process (UV/TiO2 PC after pH-temperature flocculation (pH-T F higher threshold flux values were observed for all feed stocks than by applying solely the pH-T F process, with an 18.8–34.2% increment. In addition, the performance of the UF membrane was also improved in terms of rejection efficiency, such that higher rejection values were yielded by the membrane for the organic pollutants (RCOD by 48.5 vs. 39.9% and 53.4 vs. 42.0%. The UF membrane performance was also improved in terms of the volume feed recovery factor (VFR, achieving up to 88.2 vs. 87.2% and 90.7 vs. 89.3%. Results in the same line were also observed when the highly polluted olives oil washing wastewater raw stream was previously mixed with the effluent stream coming from the washing of the olives. This permits the UF to permeate, achieving the standard limits to reuse the purified effluent for irrigation purposes (COD values below 1000 mg·L−1, which makes the treatment process cost-effective and results in making the olive oil production process environmentally friendly.En este estudio se aborda el rendimiento de una membrana de ultrafiltración (UF para el tratamiento de los efluentes generados por la industria oleícola, mediante la aplicación de distintos pretratamientos. Tras aplicar un proceso fotocatalítico (UV/TiO2 PC después de una floculación pH-temperatura (pH-T F se observaron flujos límite para todos los efluentes mayores que tras la aplicación únicamente del proceso pH-T F, con incrementos del 18.8–34.2 %. Además, el rendimiento de la membrana de UF mejoró en términos de eficiencia de rechazo, con mayores valores de rechazo respecto de los contaminantes orgánicos (RCOD, 48.5 vs. 39.9 % y 53.4 vs. 42.0 %. El rendimiento de

  12. A survey of structure characterization methods for ultrafiltration and reverse osmosis membranes

    NARCIS (Netherlands)

    Smolders, C.A.; Mulder, M.H.V.; van der Velden, P.M.

    1976-01-01

    Asymmetric membranes consist of a thin skin, which is permselective to certain molecules in solution, and a porous support, serving as a mechanical support layer and also as a transport layer for the permeate. Both in ultrafiltration and in hyperfiltration (reverse osmosis) asymmetric membranes are

  13. Preparation of PES ultrafiltration membranes with natural amino acids based zwitterionic antifouling surfaces

    International Nuclear Information System (INIS)

    Xu, Chen; Liu, Xiaojiu; Xie, Binbin; Yao, Chen; Hu, Wenhan; Li, Yi; Li, Xinsong

    2016-01-01

    Highlights: • Amino acids have been successfully grafted onto the surface of PES membranes via amino groups induced epoxy ring opening. • Zwitterionic PES ultrafiltration membranes exhibit excellent antifouling performance and improved permeation properties. • A facile strategy to combat fouling of PES ultrafiltration membranes is developed by grafting natural amino acids. - Abstract: In this report, a simple and facile approach to enhance the antifouling property of poly(ether sulfone) (PES) ultrafiltration membrane was developed by grafting natural amino acids onto surface. First of all, poly(ether sulfone) composite membranes blended with poly(glycidyl methacrylate) were fabricated by phase inversion method followed by grafting of different types of natural amino acids onto the membrane surface through epoxy ring opening reaction. The analysis of attenuated total reflectance Fourier transform infrared spectroscopy (ATR/FTIR) and X-ray photoelectron spectroscopy (XPS) verified the substantial enrichment of amino acids onto the surface of PES membranes. The hydrophilicity of the PES membranes was improved after grafting amino acids. The mechanical property and morphologies of the PES membranes proved that their basic performances were not obviously affected by grafting reaction, and these parameters were all still in the typical range for ultrafiltration membranes. The antifouling property of the grafted PES membranes against bovine serum albumin (BSA) and lysozyme (Lyz) was investigated in detail. It was found that PES membranes incorporated with neutral amino acids exhibited higher fouling resistance to both BSA and Lyz than the parent PES membrane. It can be ascribed to the formation of zwitterionic structure on the surface consisting of protonated secondary amino cations and carboxyl anions. Meanwhile, PES membranes grafted with charged amino acids had better antifouling properties against protein with same electric charges and improved adsorption

  14. Preparation of PES ultrafiltration membranes with natural amino acids based zwitterionic antifouling surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Chen; Liu, Xiaojiu; Xie, Binbin; Yao, Chen [School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189 (China); Hu, Wenhan; Li, Yi [Suzhou Faith & Hope Membrane Technology Co., Ltd., Suzhou, 215000 (China); Li, Xinsong, E-mail: lixs@seu.edu.cn [School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189 (China)

    2016-11-01

    Highlights: • Amino acids have been successfully grafted onto the surface of PES membranes via amino groups induced epoxy ring opening. • Zwitterionic PES ultrafiltration membranes exhibit excellent antifouling performance and improved permeation properties. • A facile strategy to combat fouling of PES ultrafiltration membranes is developed by grafting natural amino acids. - Abstract: In this report, a simple and facile approach to enhance the antifouling property of poly(ether sulfone) (PES) ultrafiltration membrane was developed by grafting natural amino acids onto surface. First of all, poly(ether sulfone) composite membranes blended with poly(glycidyl methacrylate) were fabricated by phase inversion method followed by grafting of different types of natural amino acids onto the membrane surface through epoxy ring opening reaction. The analysis of attenuated total reflectance Fourier transform infrared spectroscopy (ATR/FTIR) and X-ray photoelectron spectroscopy (XPS) verified the substantial enrichment of amino acids onto the surface of PES membranes. The hydrophilicity of the PES membranes was improved after grafting amino acids. The mechanical property and morphologies of the PES membranes proved that their basic performances were not obviously affected by grafting reaction, and these parameters were all still in the typical range for ultrafiltration membranes. The antifouling property of the grafted PES membranes against bovine serum albumin (BSA) and lysozyme (Lyz) was investigated in detail. It was found that PES membranes incorporated with neutral amino acids exhibited higher fouling resistance to both BSA and Lyz than the parent PES membrane. It can be ascribed to the formation of zwitterionic structure on the surface consisting of protonated secondary amino cations and carboxyl anions. Meanwhile, PES membranes grafted with charged amino acids had better antifouling properties against protein with same electric charges and improved adsorption

  15. Drinking water treatment by ultrafiltration membranes; Potabilizacion de aguas mediante membranas de ultrafiltracion

    Energy Technology Data Exchange (ETDEWEB)

    Rojas, J. C.; Moreno, B.; Poyatos, J. M.; Rua, A. de la; Perez, J. J.; Plaza, F.; Garralon, G.; Gomez, M. A.

    2007-07-01

    In this paper the application of ultrafiltration technology as a drinking water treatment was evaluated. For this reason, a pilot scale ultrafiltration module equipped with a flat membrane cassette of polyvinylidene fluoride (PVDF) with an average pore size of 0.05 {mu}m was used. Different types of artificially polluted waters (with urban waste water and soil suspension) were used. the performance of ultrafiltration technology was evaluated by means of different physicochemical and microbiological parameters both feed water and treated water. Bacterial and viral indicators were efficiently retained by the system and the same time organoleptic parameters were improved. However, it is important to emphasize the problems that the ultrafiltration technology has for the eliminate dissolves compounds remaining the most dissolve organic compounds in the feed water. (Author) 11 refs.

  16. A hybrid microbial fuel cell membrane bioreactor with a conductive ultrafiltration membrane biocathode for wastewater treatment

    KAUST Repository

    Malaeb, Lilian; Katuri, Krishna; Logan, Bruce E.; Maab, Husnul; Nunes, Suzana Pereira; Saikaly, Pascal

    2013-01-01

    A new hybrid, air-biocathode microbial fuel cell-membrane bioreactor (MFC-MBR) system was developed to achieve simultaneous wastewater treatment and ultrafiltration to produce water for direct reclamation. The combined advantages of this system were achieved by using an electrically conductive ultrafiltration membrane as both the cathode and the membrane for wastewater filtration. The MFC-MBR used an air-biocathode, and it was shown to have good performance relative to an otherwise identical cathode containing a platinum catalyst. With 0.1 mm prefiltered domestic wastewater as the feed, the maximum power density was 0.38 W/m2 (6.8 W/m3) with the biocathode, compared to 0.82 W/m2 (14.5 W/m3) using the platinum cathode. The permeate quality from the biocathode reactor was comparable to that of a conventional MBR, with removals of 97% of the soluble chemical oxygen demand, 97% NH3-N, and 91% of total bacteria (based on flow cytometry). The permeate turbidity was <0.1 nephelometric turbidity units. These results show that a biocathode MFC-MBR system can achieve high levels of wastewater treatment with a low energy input due to the lack of a need for wastewater aeration. © 2013 American Chemical Society.

  17. A hybrid microbial fuel cell membrane bioreactor with a conductive ultrafiltration membrane biocathode for wastewater treatment

    KAUST Repository

    Malaeb, Lilian

    2013-10-15

    A new hybrid, air-biocathode microbial fuel cell-membrane bioreactor (MFC-MBR) system was developed to achieve simultaneous wastewater treatment and ultrafiltration to produce water for direct reclamation. The combined advantages of this system were achieved by using an electrically conductive ultrafiltration membrane as both the cathode and the membrane for wastewater filtration. The MFC-MBR used an air-biocathode, and it was shown to have good performance relative to an otherwise identical cathode containing a platinum catalyst. With 0.1 mm prefiltered domestic wastewater as the feed, the maximum power density was 0.38 W/m2 (6.8 W/m3) with the biocathode, compared to 0.82 W/m2 (14.5 W/m3) using the platinum cathode. The permeate quality from the biocathode reactor was comparable to that of a conventional MBR, with removals of 97% of the soluble chemical oxygen demand, 97% NH3-N, and 91% of total bacteria (based on flow cytometry). The permeate turbidity was <0.1 nephelometric turbidity units. These results show that a biocathode MFC-MBR system can achieve high levels of wastewater treatment with a low energy input due to the lack of a need for wastewater aeration. © 2013 American Chemical Society.

  18. Enhancing performance and surface antifouling properties of polysulfone ultrafiltration membranes with salicylate-alumoxane nanoparticles

    Science.gov (United States)

    Mokhtari, Samaneh; Rahimpour, Ahmad; Shamsabadi, Ahmad Arabi; Habibzadeh, Setareh; Soroush, Masoud

    2017-01-01

    To improve the hydrophilicity and antifouling properties of polysulfone (PS) ultrafiltration membranes, we studied the use of salicylate-alumoxane (SA) nanoparticles as a novel hydrophilic additive. The effects of SA nanoparticles on the membrane characteristics and performance were investigated in terms of membrane structure, permeation flux, solute rejection, hydrophilicity, and antifouling ability. The new mixed-matrix membranes (MMMs) possess asymmetric structures. They have smaller finger-like pores and smoother surfaces than the neat PS membranes. The embedment of SA nanoparticles in the polymer matrix and the improvement of surface hydrophilicity were investigated. Ultrafiltration experiments indicated that the pure-water flux of the new MMMs initially increases with SA nanoparticles loading followed by a decrease at high loadings. Higher BSA solution flux was achieved for the MMMs compared to the neat PS membranes. Membranes with 1 wt.% SA nanoparticles exhibit the highest flux recovery ratio of 87% and the lowest irreversible fouling of 13%.

  19. Improved antifouling performance of ultrafiltration membrane via preparing novel zwitterionic polyimide

    Science.gov (United States)

    Huang, Haitao; Yu, Jiayu; Guo, Hanxiang; Shen, Yibo; Yang, Fan; Wang, Han; Liu, Rong; Liu, Yang

    2018-01-01

    On the basis of the outstanding fouling resistance of zwitterionic polymers, an antifouling ultrafiltration membrane was fabricated through phase inversion induced by immersion precipitation method, directly using the novel zwitterionic polyimide (Z-PI), which was synthesized via a two-step procedure including polycondensation and quaternary amination reaction, as membrane material. The chemical structure and composition of the obtained polymer were confirmed by using FTIR, 1H NMR and XPS analysis, and its thermal stability was thoroughly characterized by TGA measurement, respectively. The introduction of zwitterionic groups into polyimide could effectively increase membrane pore size, porosity and wettability, and convert the membrane surface from hydrophobic to highly hydrophilic. As a result, Z-PI membrane displayed significantly improved water permeability compared with that of the reference polyimide (R-PI) membrane without having an obvious compromise in protein rejection. According to the static adsorption and dynamic cycle ultrafiltration experiments of bovine serum albumin (BSA) solution, Z-PI membrane exhibited better fouling resistant ability, especially irreversible fouling resistant ability, suggesting superior antifouling property and long-term performance stability. Moreover, Z-PI membrane had a water flux recovery ratio of 93.7% after three cycle of BSA solution filtration, whereas only about 68.5% was obtained for the control R-PI membrane. These findings demonstrated the advantages of Z-PI membrane material and aimed to provide a facile and scalable method for the large-scale preparation of low fouling ultrafiltration membranes for potential applications.

  20. Molecular Mechanisms of Ultrafiltration Membrane Fouling in Polymer-Flooding Wastewater Treatment: Role of Ions in Polymeric Fouling.

    Science.gov (United States)

    Liu, Guicai; Yu, Shuili; Yang, Haijun; Hu, Jun; Zhang, Yi; He, Bo; Li, Lei; Liu, Zhiyuan

    2016-02-02

    Polymer (i.e., anionic polyacrylamide (APAM)) fouling of polyvinylidene fluoride (PVDF) ultrafiltration (UF) membranes and its relationships to intermolecular interactions were investigated using atomic force microscopy (AFM). Distinct relations were obtained between the AFM force spectroscopy measurements and calculated fouling resistance over the concentration polarization layer (CPL) and gel layer (GL). The measured maximum adhesion forces (Fad,max) were closely correlated with the CPL resistance (Rp), and the proposed molecular packing property (largely based on the shape of AFM force spectroscopy curve) of the APAM chains was related to the GL resistance (Rg). Calcium ions (Ca(2+)) and sodium ions (Na(+)) caused more severe fouling. In the presence of Ca(2+), the large Rp corresponded to high foulant-foulant Fad,max, resulting in high flux loss. In addition, the Rg with Ca(2+) was minor, but the flux recovery rate after chemical cleaning was the lowest, indicating that Ca(2+) created more challenges in GL cleaning. With Na(+), the fouling behavior was complicated and concentration-dependent. The GL structures with Na(+), which might correspond to the proposed molecular packing states among APAM chains, played essential roles in membrane fouling and GL cleaning.

  1. [Study on the interface of human hepatocyte/micropore polypropylene ultrafiltration membrane].

    Science.gov (United States)

    Peng, Cheng-Hong; Han, Bao-San; Gao, Chang-You; Ma, Zu-Wei; Zhao, Zhi-Ming; Wang, Yong; Liu, Hong; Zhang, Gui-di; Yang, Mei-Juan

    2004-09-02

    To found a new interface of human hepatocyte/micropore polypropylene ultrafiltration membrane (MPP) with good cytocompatibility so as to construct bioartificial bioreactor with polypropylene hollow fibers in future. MPP ultrafiltration membrane underwent chemical grafting modification through ultraviolet irradiation and Fe(2+) reduction. The contact angles of MPP and the modified MPP membranes were measured. Human hepatic cells L-02 were cultured. MPP and modified MPP membranes were spread on the wells of culture plate and human hepatic cells and cytodex 3 were inoculated on them. Different kinds of microscopy were used to observe the morphology of these cells. The water contact angle of MPP and the modified MPP membranes decreased from 78 degrees +/- 5 degrees to 27 degrees +/- 4 degrees (P < 0.05), which indicated that the hydrophilicity of the membrane was improved obviously after the grafting modification. Human hepatocyte L-02 did not adhere to and spread on the modified MPP membrane surface, and only grew on the microcarrier cytodex 3 with higher density and higher proliferation ratio measured by MTT. Grafting modification of acrylamide on MPP membrane is a good method to improve the human hepatocyte cytocompatibility with MPP ultrafiltration membrane.

  2. Preparation of ultrafiltration membrane by phase separation coupled with microwave irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Suryani, Puput Eka [Department of Chemical Engineering, Faculty of Engineering, Diponegoro University Jl. Prof. Soedarto, Semarang 50275, Central Java (Indonesia); Department of Chemical Engineering, Faculty of Engineering, UniversitasMuhammadiyah Surakarta Jl. Jendral Ahmad Yani, Surakarta 57102, Central Java (Indonesia); Purnama, Herry [Department of Chemical Engineering, Faculty of Engineering, UniversitasMuhammadiyah Surakarta Jl. Jendral Ahmad Yani, Surakarta 57102, Central Java (Indonesia); Susanto, Heru, E-mail: heru.susanto@undip.ac.id [Department of Chemical Engineering, Faculty of Engineering, Diponegoro University Jl. Prof. Soedarto, Semarang 50275, Central Java (Indonesia)

    2015-12-29

    Preparation of low fouling ultrafiltration membrane is still a big challenge in the membrane field. In this paper, polyether sulfone (PES) ultrafiltration membranes were prepared by non-solvent-induced phase separation (NIPS) coupled with microwave irradiation. Polyethylene glycol (PEG) and polyethylene glycol methacrylate (PEGMA) were used as additives to improve membrane hydrophilicity. In this study, the concentration of additive, irradiation time and microwave power was varied. The membranes were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy, while the performances were tested by adsorptive and ultrafiltration fouling experiments. The results show that the irradiation time and irradiation power are very important parameter that influence the membrane characteristic. In addition, type and concentration of additive are other important parameters. The results suggest that microwave irradiation is the most important parameter influencing the membrane characteristic. Both pure water flux and fouling resistance increase with increasing irradiation time, power irradiation, and additive concentration. PES membrane with addition of 10% w/w PEG and irradiated by 130 W microwave power for 180 seconds is the best membrane performance.

  3. Ceramic membrane by tape casting and sol-gel coating for microfiltration and ultrafiltration application

    Science.gov (United States)

    Das, Nandini; Maiti, H. S.

    2009-11-01

    Alumina membrane filters in the form of thin (0.3-0.8 mm) discs of 25-30 mm diameter suitable for microfiltration application have been fabricated by tape-casting technique. Further using this microfiltration membrane as substrate, boehmite sol coating was applied on it and ultrafiltration membrane with very small thickness was formed. The pore size of the microfiltration membrane could be varied in the range of 0.1-0.7 μm through optimisation of experimental parameter. In addition, each membrane shows a very narrow pore size distribution. The most important factor, which determines the pore size of the membrane, is the initial particle size and its distribution of the ceramic powder. The top thin ultrafiltration, boehmite layer was prepared by sol-gel method, with a thickness of 0.5 μm. Particle size of the sol was approximately 30-40 nm. The structure and formation of the layer was analysed through TEM. At 550 °C formation of the top layer was completed. The pore size of the ultrafiltration membrane measured from TEM micrograph was almost 10 nm. Results of microbial (Escherichia coli—smallest-sized water-borne bacteria) test confirm the possibility of separation through this membrane

  4. Exploration of zwitterionic cellulose acetate antifouling ultrafiltration membrane for bovine serum albumin (BSA) separation.

    Science.gov (United States)

    Liu, Yang; Huang, Haitao; Huo, Pengfei; Gu, Jiyou

    2017-06-01

    This study focused on the preparation of a new kind of membrane material, zwitterionic cellulose acetate (ZCA), via a three-step procedure consist of oxidization, Schiff base and quaternary amination reaction, and the fabrication of antifouling ZCA ultrafiltration membrane by the non-solvent-induced phase separation method (NIPS). The morphologies, surface chemical structures and compositions of the obtained CA and ZCA membranes were thoroughly characterized by field emission scanning electron microscopy (FE-SEM) with energy dispersive X-ray (EDX) spectroscopy, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), respectively. Meanwhile, the thermal stability, porosity and average pore size of two investigated membranes were also studied. As a result, the ZCA membrane displayed significantly improved hydrophilicity and water permeability compared with those of the reference CA membrane, despite a slight decrease in the protein rejection ratio. According to the cycle ultrafiltration performance of bovine serum albumin (BSA) solution and protein adsorption experiment, ZCA membrane exhibited better flux recovery property and fouling resistant ability, especially irreversible fouling resistant ability, suggesting superior antifouling performance. This new approach gives polymer-based membrane a long time life and excellent ultrafiltration performance, and seems promising for potential applications in the protein separation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Crossflow ultrafiltration of raw municipal wastewater : Investigations using PVDF tubular membranes

    NARCIS (Netherlands)

    Ravazzini, A.M.

    2008-01-01

    In the usual wastewater treatment schemes the application of membranes follows a biological process. However, ultrafiltration of untreated wastewater produces permeate free of particles and bacteria in one single step and could represent the starting point for new water-reuse concepts. This thesis

  6. Enhanced starch hydrolysis using α-amylase immobilized on cellulose ultrafiltration affinity membrane.

    Science.gov (United States)

    Konovalova, Viktoriia; Guzikevich, Kateryna; Burban, Anatoliy; Kujawski, Wojciech; Jarzynka, Karolina; Kujawa, Joanna

    2016-11-05

    In order to prepare ultrafiltration membranes possessing biocatalytic properties, α-amylase has been immobilized on cellulose membranes. Enzyme immobilization was based on a covalent bonding between chitosan and a surface of cellulose membrane, followed by an attachment of Cibacron Blue F3G-A dye as affinity ligand. Various factors affecting the immobilization process, such as enzyme concentration, pH of modifying solution, zeta-potential of membrane surface, and stability of immobilized enzyme were studied. The applicability of immobilized α-amylase has been investigated in ultrafiltration processes. The immobilization of α-amylase on membrane surface allows to increase the value of mass transfer coefficient and to decrease the concentration polarization effect during ultrafiltration of starch solutions. The enzyme layer on the membrane surface prevents a rapid increase of starch concentration due to the amylase hydrolysis of starch in the boundary layer. The presented affinity immobilization technique allows also for the regeneration of membranes from inactivated enzyme. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Ceramic membrane ultrafiltration of natural surface water with ultrasound enhanced backwashing.

    Science.gov (United States)

    Boley, A; Narasimhan, K; Kieninger, M; Müller, W-R

    2010-01-01

    Ultrafiltration membrane cleaning with ultrasound enhanced backwashing was investigated with two ceramic membrane systems in parallel. One of them was subjected to ultrasound during backwashing, the other acted as a reference system. The feed water was directly taken from a creek with a sedimentation process as only pre-treatment. The cleaning performance was improved with ultrasound but after 3 weeks of operation damages occurred on the membranes. These effects were studied with online measurements of flux, trans-membrane-pressure and temperature, but also with integrity tests, turbidity measurements and visual examination.

  8. Deposition of thin ultrafiltration membranes on commercial SiC microfiltration tubes

    DEFF Research Database (Denmark)

    Facciotti, Marco; Boffa, Vittorio; Magnacca, Giuliana

    2014-01-01

    Porous SiC based materials present high mechanical, chemical and thermal robustness, and thus have been largely applied to water-filtration technologies. In this study, commercial SiC microfiltration tubes with nominal pore size of 0.04 m were used as carrier for depositing thin aluminium oxide....... After 5 times coating, a 5.6 µm thick γ-Al2O3 layer was obtained. This membrane shows retention of ~75% for polyethylene glycol molecules with Mn of 8 and 35 kDa, indicating that, despite their intrinsic surface roughness, commercial SiC microfiltration tubes can be applied as carrier for thin...... ultrafiltration membranes. This work also indicates that an improvement of the commercial SiC support surface smoothness may greatly enhance permeance and selectivity of Υ-Al2O3 ultrafiltration membranes by allowing the deposition of thinner defect-free layers....

  9. Novel adsorptive ultrafiltration membranes derived from polyvinyltetrazole-co-polyacrylonitrile for Cu(II) ions removal

    KAUST Repository

    Kumar, Mahendra

    2016-05-04

    Novel adsorptive ultrafiltration membranes were manufactured from synthesized polyvinyltetrazole−co−polyacrylonitrile (PVT−co−PAN) by nonsolvent induced phase separation (NIPS). PVT−co−PAN with various degree of functionalization (DF) was synthesized via a [3+2] cycloaddition reaction at 60°C using a commercial PAN. PVT−co−PAN with varied DF was then explored to prepare adsorptive membranes. The membranes were characterized by surface zeta potential and static water contact angle measurements, scanning electron microscopy as well as atomic force microscopy (AFM) techniques. It was shown that PVT segments contributed to alter the pore size, charge and hydrophilic behavior of the membranes. The membranes became more negatively charged and hydrophilic after addition of PVT segments. The PVT segments in the membranes served as the major binding sites for adsorption of Cu(II) ions from aqueous solution. The maximum adsorption of Cu(II) ions by the membranes in static condition and in a continuous ultrafiltration of 10 ppm solution was attained at pH = 5. The adsorption data suggest that the Freundlich isotherm model describes well Cu(II) ions adsorption on the membranes from aqueous solution. The adsorption capacity obtained from the Freundlich isotherm model was 44.3 mg g−1; this value is higher than other membrane adsorption data reported in the literature. Overall, the membranes fabricated from PVT−co−PAN are attractive for efficient removal of heavy metal ions under the optimized conditions.

  10. Novel adsorptive ultrafiltration membranes derived from polyvinyltetrazole-co-polyacrylonitrile for Cu(II) ions removal

    KAUST Repository

    Kumar, Mahendra; Shevate, Rahul; Hilke, Roland; Peinemann, Klaus-Viktor

    2016-01-01

    Novel adsorptive ultrafiltration membranes were manufactured from synthesized polyvinyltetrazole−co−polyacrylonitrile (PVT−co−PAN) by nonsolvent induced phase separation (NIPS). PVT−co−PAN with various degree of functionalization (DF) was synthesized via a [3+2] cycloaddition reaction at 60°C using a commercial PAN. PVT−co−PAN with varied DF was then explored to prepare adsorptive membranes. The membranes were characterized by surface zeta potential and static water contact angle measurements, scanning electron microscopy as well as atomic force microscopy (AFM) techniques. It was shown that PVT segments contributed to alter the pore size, charge and hydrophilic behavior of the membranes. The membranes became more negatively charged and hydrophilic after addition of PVT segments. The PVT segments in the membranes served as the major binding sites for adsorption of Cu(II) ions from aqueous solution. The maximum adsorption of Cu(II) ions by the membranes in static condition and in a continuous ultrafiltration of 10 ppm solution was attained at pH = 5. The adsorption data suggest that the Freundlich isotherm model describes well Cu(II) ions adsorption on the membranes from aqueous solution. The adsorption capacity obtained from the Freundlich isotherm model was 44.3 mg g−1; this value is higher than other membrane adsorption data reported in the literature. Overall, the membranes fabricated from PVT−co−PAN are attractive for efficient removal of heavy metal ions under the optimized conditions.

  11. Ultrafiltration of biologically treated domestic wastewater: How membrane properties influence performance

    KAUST Repository

    Filloux, Emmanuelle; Teychene, Benoî t; Tazi-Pain, Annie; Croue, Jean-Philippe

    2014-01-01

    In this study, the impact of membrane properties on membrane fouling and permeate water quality was investigated. Short- and long-term laboratory scale experiments using four commercially available hollow fiber UF membranes were performed to study the impact of membrane properties on reversible and irreversible fouling. No significant differences in terms of permeate quality (i.e. biopolymer rejection) were observed over the four tested membranes. It was found that membrane characteristics including pore size, pore distribution and especially materials had a strong impact on the filtration performances in terms of both reversible and irreversible fouling. The short-term filtration tests showed that due to its specific hydrodynamic condition only the inside-out mode UF membrane was subjected to irreversible fouling. These data demonstrate the importance of membrane selection with appropriate operating conditions for optimum performances. The added value of membrane characterization to lab-scale filtration tests for membrane performance was discussed. © 2014 Elsevier B.V. All rights reserved.

  12. Ultrafiltration of biologically treated domestic wastewater: How membrane properties influence performance

    KAUST Repository

    Filloux, Emmanuelle

    2014-09-01

    In this study, the impact of membrane properties on membrane fouling and permeate water quality was investigated. Short- and long-term laboratory scale experiments using four commercially available hollow fiber UF membranes were performed to study the impact of membrane properties on reversible and irreversible fouling. No significant differences in terms of permeate quality (i.e. biopolymer rejection) were observed over the four tested membranes. It was found that membrane characteristics including pore size, pore distribution and especially materials had a strong impact on the filtration performances in terms of both reversible and irreversible fouling. The short-term filtration tests showed that due to its specific hydrodynamic condition only the inside-out mode UF membrane was subjected to irreversible fouling. These data demonstrate the importance of membrane selection with appropriate operating conditions for optimum performances. The added value of membrane characterization to lab-scale filtration tests for membrane performance was discussed. © 2014 Elsevier B.V. All rights reserved.

  13. Characterization of a non-fouling ultrafiltration membrane

    DEFF Research Database (Denmark)

    Wei, J.; Helm, G.S.; Corner-Walker, N.

    2006-01-01

    This report describes the properties of surface-modified poly(vinylidene fluoride) (PVDF) membranes. These membranes were created by coating hydrophilic polymers on the support PVDF membrane to reduce the tendency to protein fouling. The modified membranes with different molecular weight cut......-off (MWCO) were characterized by filtration studies using bovine serum albumin (BSA) and an enzyme solution as test media, and the membranes exhibited the non-fouling property. The surface chemistry of the unmodified and modified PVDF membranes was characterized by X-ray photoelectron spectroscopy (XPS......) and time-of-flight secondary ion mass spectroscopy (ToF-SIMS). These surface sensitive techniques were used to confirm the successful surface modification. ToF-SIMS imaging visualizes the distribution of the coating layer on the PVDF membrane. Furthermore, the amount of protein adsorption onto the membrane...

  14. Preparation of hydrophilic and antifouling polysulfone ultrafiltration membrane derived from phenolphthalin by copolymerization method

    International Nuclear Information System (INIS)

    Liu, Zhixiao; Mi, Zhiming; Chen, Chunhai; Zhou, Hongwei; Zhao, Xiaogang; Wang, Daming

    2017-01-01

    Graphical abstract: The mechanisms fouling and cleaning process of PSF-COOH membranes (A) the content of carboxyl less than 80%. (B) the content of carboxyl at 80%, 100%. - Highlights: • Phenolphthalin (PPL) containing carboxyl was successfully introduced into the molecule backbone of polysulfone (PSF). • A series of PSF-COOH copolymers with different carboxylation degree was synthesized and prepared as ultrafiltration membranes. • The introduction of PPL significantly improved the hydrophilicity, permeation flux and antifouling property of membranes. • This method is valuable for large-scale industrial production of hydrophilic membrane material. - Abstract: In this task, carboxylated polysulfone (PSF-COOH) was achieved by introducing the monomer of phenolphthalin (PPL) containing carboxyl to the molecule backbone of polysulfone (PSF). And a series of PSF-COOH copolymers with different carboxylation degree was synthesized by adjusting the molar (%) of bisphenol A (BPA) and PPL in direct copolymerization method and was prepared as PSF-COOH ultrafiltration membranes via phase separation method. The effect of PPL molar (%) in copolymers on the morphology, hydrophilicity, permeation flux, antifouling and mechanical properties of membranes was investigated by scanning electron microscope (SEM), atomic force microscope (AFM), water contact angle, ultrafiltration experiments and universal testing machine, respectively. The results showed that with the increased carboxyl content in membranes, the hydrophilicity, permeation fluxes and antifouling properties of membranes gradually increased. When the molar (%) of PPL to BPA was 100:0, the membrane exhibited the highest pure water flux (329.6 L/m"2 h) and the maximum flux recovery rate (92.5%). When the content of carboxyl in the membrane was 80% or more, after three cycles of BSA solution (1 g/L) filtration, the flux recovery rate was basically constant or showed a slightly increase. Thus, it can achieve the goal of

  15. Preparation of hydrophilic and antifouling polysulfone ultrafiltration membrane derived from phenolphthalin by copolymerization method

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhixiao; Mi, Zhiming; Chen, Chunhai; Zhou, Hongwei; Zhao, Xiaogang; Wang, Daming, E-mail: wangdaming@jlu.edu.cn

    2017-04-15

    Graphical abstract: The mechanisms fouling and cleaning process of PSF-COOH membranes (A) the content of carboxyl less than 80%. (B) the content of carboxyl at 80%, 100%. - Highlights: • Phenolphthalin (PPL) containing carboxyl was successfully introduced into the molecule backbone of polysulfone (PSF). • A series of PSF-COOH copolymers with different carboxylation degree was synthesized and prepared as ultrafiltration membranes. • The introduction of PPL significantly improved the hydrophilicity, permeation flux and antifouling property of membranes. • This method is valuable for large-scale industrial production of hydrophilic membrane material. - Abstract: In this task, carboxylated polysulfone (PSF-COOH) was achieved by introducing the monomer of phenolphthalin (PPL) containing carboxyl to the molecule backbone of polysulfone (PSF). And a series of PSF-COOH copolymers with different carboxylation degree was synthesized by adjusting the molar (%) of bisphenol A (BPA) and PPL in direct copolymerization method and was prepared as PSF-COOH ultrafiltration membranes via phase separation method. The effect of PPL molar (%) in copolymers on the morphology, hydrophilicity, permeation flux, antifouling and mechanical properties of membranes was investigated by scanning electron microscope (SEM), atomic force microscope (AFM), water contact angle, ultrafiltration experiments and universal testing machine, respectively. The results showed that with the increased carboxyl content in membranes, the hydrophilicity, permeation fluxes and antifouling properties of membranes gradually increased. When the molar (%) of PPL to BPA was 100:0, the membrane exhibited the highest pure water flux (329.6 L/m{sup 2} h) and the maximum flux recovery rate (92.5%). When the content of carboxyl in the membrane was 80% or more, after three cycles of BSA solution (1 g/L) filtration, the flux recovery rate was basically constant or showed a slightly increase. Thus, it can achieve the

  16. A new method to determine the skin thickness of asymmetric UF-membranes using colloidal gold particles

    NARCIS (Netherlands)

    Cuperus, Folkert Petrus; Bargeman, Derk; Smolders, C.A.

    1990-01-01

    In this paper a new method is presented for the determination of the skin thickness of asymmetric ultrafiltration membranes. The method is based on the use of well-defined, uniformly sized colloidal gold particles, permeated from the sublayer side of the membrane, combined with electron microscopic

  17. The processing of used cooking oil (yellow grease) using combination of adsorption and ultrafiltration membrane processes

    Science.gov (United States)

    Rosnelly, C. M.; Sofyana; Amalia, D.; Sarah, S.

    2018-03-01

    Yellow grease is used cooking oil whose quality has degraded due to the oxidation, polymerization, or hydrolysis process. In previous studies, yellow grease refining had been conducted either by adsorption or by using membrane. In this study, adsorption process using adsorbent from bagasse activated with H3PO4 12.5%, and ultrafiltration using Polyethersulfone (PES) membrane were combined. In adsorption stage, several variation of bagasse mass was fed into 200 ml of yellow grease and stirred for 60 minutes at 60 rpm. Yellow grease produced from adsorption with best condition was then processed using ultrafiltration membran that is PES membran with concentration by 15 wt % with transmembrane pressure variation by 0.5; 1; 1.5; 2; and 2.5 Bar. Analysis of yellow grease characteristics before refined showed its acid number, peroxide number, iodine number, and water content respectively by 2.68 mgKOH/Kg; 5.97 Meq/Kg; 51,48; and 1.29%. Characteristics of yellow grease after adsorption at its best condition on the parameters of acid number, peroxide number, iodine number, and water content are respectively by 2.55 mgKOH/Kg; 4.19 Meq/Kg; 40,02; and 0.27%. Characteristics of yellow grease after ultrafiltration at its best condition on the parameters of acid number, peroxide number, iodine number, and water content are respectively by 1.12 mgKOH/Kg; 1.8 Meq/Kg; 41,36; and 0.02%. Combination of adsorption and ultrafiltration processes for yellow grease processing showed decreasing value on the parameters of acid number, peroxide number, and water content that conforms to the SNI quality standard, but has not been able to increase the iodine number.

  18. Pretreatment with ceramic membrane microfiltration in the clarification process of sugarcane juice by ultrafiltration

    Directory of Open Access Journals (Sweden)

    Priscilla dos Santos Gaschi

    2014-04-01

    Full Text Available In the present study, the sugar cane juice from COCAFE Mill, was clarified using tubular ceramic membranes (α-Al2O3/TiO2 with pore size of 0.1 and 0.3 µm, and membrane area of 0.005 m2. Experiments were performed in batch with sugar cane juice, in a pilot unit of micro and ultrafiltration using the principle of tangential filtration. The sugar cane juice was settled for one hour and the supernatant was treated by microfiltration. After that, the MF permeate was ultrafiltered. The experiments of micro and ultrafiltration were carried out at 65ºC and 1 bar. The ceramic membranes were able to remove the colloidal particles, producing a limpid permeated juice with color reduction. The clarification process with micro- followed by ultrafiltration produced a good result with an average purity rise of 2.74 units, 99.4% lower turbidity and 44.8% lighter color in the permeate.

  19. Differential natural organic matter fouling of ceramic versus polymeric ultrafiltration membranes.

    Science.gov (United States)

    Lee, Seung-Jin; Kim, Jae-Hong

    2014-01-01

    Ceramic ultrafiltration membranes has drawn increasing attention in drinking water treatment sectors as an alternative to traditional polymeric counterparts, yet only limited information has been made available about the characteristics of ceramic membrane fouling by natural organic matter. The effects of solution chemistry including ionic strength, divalent ion concentration and pH on the flux behavior were comparatively evaluated for ceramic and polymeric ultrafiltration of synthetic water containing model natural organic matter. Filtration characteristics were further probed via resistance-in-series model analysis, fouling visualization using quantum dots, batch adsorption test, contact angle measurement, solute-membrane surface adhesion force measurement, and quantitative comparison of fouling characteristics between ceramic and polymeric membranes. The results collectively suggested that the effects of solution chemistry on fouling behavior of ceramic membranes were generally similar to polymeric counterparts in terms of trends, while the extent varied significantly depending on water quality parameters. Lower fouling tendency and enhanced cleaning efficiency were observed with the ceramic membrane, further promoting the potential for ceramic membrane application to surface water treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Recovery of carbohydrates from nixtamalization wastewaters (nejayote) by ultrafiltration

    OpenAIRE

    Castro-Muñoz, R.; Cerón-Montes, G.I.; Barragán-Huerta, B.E.; Yáñez-Fernández, J.

    2015-01-01

    Nejayote extract is a polluting by-product from Nixtamalization of maize; therefore in this study was evaluated a membrane operation for the treatment and recovery of industrial usable compounds. Nejayote extract was processed by ultrafiltration (UF) membrane on laboratory scale. In experimental tests performed according to the total recycle mode, the effect of transmembrane pressure (TMP) on permeate flux has been studied. The permeate flux no showed a considerable increase for TMP values hi...

  1. Performance study of ultrafiltration membrane with bovine serum albumin as feed solution

    International Nuclear Information System (INIS)

    Syahril Ahmad

    2009-01-01

    Bovine serum albumin solutions at different temperature, pH, flow rate and operation pressure have been used as feed solution for studying performance of ultrafiltration membrane. Polysulfone membranes used for this experiment were in form of hollow fibers that have Molecular Weight Cut Off (MWCO) 60 kDa. Observation was focused on flux parameter and rejection coefficient towards protein during the process. Result shows that temperature, pH of BSA feed solution, flow rate and operation pressure can affect the flux and rejection coefficient of membrane. High temperature feed solution tend to decrease the flux but increase rejection coefficient. Rejection coefficient of membrane will increase while flux decreasing at pH of feed solution near to protein isoelectric point. High pressure of feed solution will increase flux but decrease rejection of membrane. Rejection of membrane will decrease and flux will increase when the process operated in slow flow rate. (author)

  2. Preparation, Characterization and Performance Studies of Active PVDF Ultrafiltration-Surfactants Membranes Containing PVP as Additive

    International Nuclear Information System (INIS)

    Nur Izzah Md Fadilah; Abdul Rahman Hassan

    2016-01-01

    The role of surfactants in the formation of active Poly(vinylidene fluoride) (PVDF) ultrafiltration (AUF) membranes was studied. The effect combination of surfactants that are Sodium dodecyl sulfate (SDS)/ Tween 80 and Tween 80/ Triton X-100 formulations on performance and morphological structures were investigated for the first time. The influence of surfactants blends on the membrane pores was also examined. Experimental data showed that combination of Tween 80/ Triton X-100 give the highest BSA permeation flux with a value of 285.51 Lm -2 h -1 . With combination of SDS/ Tween 80, the AUF membrane showed the highest protein rejection up to 93 % and 79 % for Bovine Serum Albumin (BSA) and Egg Albumin (EA), respectively. Moreover, membranes characterization demonstrated that the addition of SDS/ Tween 80 and Tween 80/ Triton X-100 were found to affect the performance, surface morphologies and membrane pores of AUF PVDF membranes. (author)

  3. Polyethersulfone/Graphene Oxide Ultrafiltration Membranes from Solutions in Ionic Liquid

    KAUST Repository

    Mahalingam, Dinesh. K.; Kim, DooLi.; Nunes, Suzana. P.

    2017-01-01

    Novel high flux polyethersulfone (PES) ultrafiltration membranes were fabricated by incorporating different amounts of graphene oxide (GO) sheets to PES as nanofillers. The membranes were prepared from solutions in 50/50 1-ethyl-3-methylimidazolium-diethylphosphate/N,N-dimethyl formamide. It was observed that the water permeance increased from 550 to 800 L m-2h-1bar-1, with incorporation of 1 wt% GO, keeping a molecular weight cut-off (MWCO) of approximately 32-34 kg mol-1. Cross-sectional scanning electron microscopy images of GO/PES membranes showed the formation of ultrathin selective layer unlike pristine membranes. Contact angle measurements confirmed the increase of hydrophilicity, by increasing the GO concentration. The rejection of humic acid and bovine serum albumin was demonstrated. The mechanical properties were improved, compared with the pristine membranes. The performance was just above the trade-off relationship between permeance and separation factor for PES membranes reported in the literature.

  4. Polyethersulfone/Graphene Oxide Ultrafiltration Membranes from Solutions in Ionic Liquid

    KAUST Repository

    Mahalingam, Dinesh. K.

    2017-07-18

    Novel high flux polyethersulfone (PES) ultrafiltration membranes were fabricated by incorporating different amounts of graphene oxide (GO) sheets to PES as nanofillers. The membranes were prepared from solutions in 50/50 1-ethyl-3-methylimidazolium-diethylphosphate/N,N-dimethyl formamide. It was observed that the water permeance increased from 550 to 800 L m-2h-1bar-1, with incorporation of 1 wt% GO, keeping a molecular weight cut-off (MWCO) of approximately 32-34 kg mol-1. Cross-sectional scanning electron microscopy images of GO/PES membranes showed the formation of ultrathin selective layer unlike pristine membranes. Contact angle measurements confirmed the increase of hydrophilicity, by increasing the GO concentration. The rejection of humic acid and bovine serum albumin was demonstrated. The mechanical properties were improved, compared with the pristine membranes. The performance was just above the trade-off relationship between permeance and separation factor for PES membranes reported in the literature.

  5. Hydrophilic Fe2O3 dynamic membrane mitigating fouling of support ceramic membrane in ultrafiltration of oil/water emulsion

    KAUST Repository

    Lu, Dongwei; Cheng, Wei; Zhang, Tao; Lu, Xinglin; Liu, Qianliang; Jiang, Jin; Ma, Jun

    2016-01-01

    Oil/water (O/W) emulsion is daily produced and difficult to be treated effectively. Ceramic membrane ultrafiltration is one of reliable processes for the treatment of O/W emulsion, yet still hindered by membrane fouling. In this study, two types of Fe2O3 dynamic membranes (i.e., pre-coated dynamic membrane and self-forming dynamic membrane) were prepared to mitigate the fouling of support ceramic membrane in O/W emulsion treatment. Pre-coated dynamic membrane (DM) significantly reduced the fouling of ceramic membrane (i.e., 10% increase of flux recovery rate), while self-forming dynamic membrane aggravated ceramic membrane fouling (i.e., 8.6% decrease of flux recovery rate) after four filtration cycles. A possible fouling mechanism was proposed to explain this phenomenon, which was then confirmed by optical images of fouled membranes and the analysis of COD rejection. In addition, the cleaning efficiency of composite membranes (i.e., Fe2O3 dynamic membrane and support ceramic membrane) was enhanced by substitution of alkalescent water backwash for deionized water backwash. The possible reason for this enhancement was also explained. Our result suggests that pre-coated Fe2O3 dynamic membrane with alkalescent water backwash can be a promising technology to reduce the fouling of ceramic membrane and enhance membrane cleaning efficiency in the treatment of oily wastewater.

  6. Hydrophilic Fe2O3 dynamic membrane mitigating fouling of support ceramic membrane in ultrafiltration of oil/water emulsion

    KAUST Repository

    Lu, Dongwei

    2016-03-17

    Oil/water (O/W) emulsion is daily produced and difficult to be treated effectively. Ceramic membrane ultrafiltration is one of reliable processes for the treatment of O/W emulsion, yet still hindered by membrane fouling. In this study, two types of Fe2O3 dynamic membranes (i.e., pre-coated dynamic membrane and self-forming dynamic membrane) were prepared to mitigate the fouling of support ceramic membrane in O/W emulsion treatment. Pre-coated dynamic membrane (DM) significantly reduced the fouling of ceramic membrane (i.e., 10% increase of flux recovery rate), while self-forming dynamic membrane aggravated ceramic membrane fouling (i.e., 8.6% decrease of flux recovery rate) after four filtration cycles. A possible fouling mechanism was proposed to explain this phenomenon, which was then confirmed by optical images of fouled membranes and the analysis of COD rejection. In addition, the cleaning efficiency of composite membranes (i.e., Fe2O3 dynamic membrane and support ceramic membrane) was enhanced by substitution of alkalescent water backwash for deionized water backwash. The possible reason for this enhancement was also explained. Our result suggests that pre-coated Fe2O3 dynamic membrane with alkalescent water backwash can be a promising technology to reduce the fouling of ceramic membrane and enhance membrane cleaning efficiency in the treatment of oily wastewater.

  7. Non-woven PET fabric reinforced and enhanced the performance of ultrafiltration membranes composed of PVDF blended with PVDF-g-PEGMA for industrial applications

    Science.gov (United States)

    Wang, Shuai; Li, Tong; Chen, Chen; Chen, Sheng; Liu, Baicang; Crittenden, John

    2018-03-01

    Ultrafiltration (UF) membranes composed of poly(vinylidene fluoride) (PVDF) blended with poly(vinylidene fluoride)-graft-poly(ethylene glycol) methyl ether methacrylate (PVDF-g-PEGMA) can present high flux and excellent foulant removal efficiencies under suitable preparation conditions. However, these PVDF/PVDF-g-PEGMA blended membranes cannot be applied industrially because of the insufficient mechanical strength (strength-to-break value of 8.4 ± 0.6 MPa). We incorporated two types of non-woven polyethylene terephthalate (PET) fabrics (thin hydrophobic and thick hydrophilic fabrics) as support layers to improve the mechanical properties of the blended membranes. The thin and thick PET fabrics were able to significantly improve the tensile strength to 23.3 ± 3.7 MPa and 30.1 ± 1.4 MPa, respectively. The PET fabrics had a limited impact on the separation-related membrane performance such as hydrophilicity, foulant rejection, whereas the mechanical strength and pure water flux was improved several folds. The enhanced flux was attributed to the higher surface porosity and wider finger-like voids in the cross-section. The thin PET fabric with larger porosity was able to maintain a consistent toughness simultaneously; thus it is recommended as a support material for this blended membrane.

  8. Hollow fiber ultrafiltration membranes with microstructured inner skin

    NARCIS (Netherlands)

    Culfaz, P.Z.; Wessling, Matthias; Lammertink, Rob G.H.

    2011-01-01

    Hollow fiber membranes with microstructured inner surfaces were fabricated from a PES/PVP blend using a spinneret with a microstructured needle. The effect of spinning parameters such as polymer dope flow rate, bore liquid flowrate, air gap and take-up speed on the microstructure and shape of the

  9. Ceramic membrane fouling during ultrafiltration of oil/water emulsions: Roles played by stabilization surfactants of oil droplets

    KAUST Repository

    Lu, Dongwei

    2015-04-07

    Oil/water (O/W) emulsion stabilized by surfactants is the part of oily wastewater that is most difficult to handle. Ceramic membrane ultrafiltration presently is an ideal process to treat O/W emulsions. However, little is known about the fouling mechanism of the ceramic membrane during O/W emulsion treatment. This paper investigated how stabilization surfactants of O/W emulsions influence the irreversible fouling of ceramic membranes during ultrafiltration. An unexpected phenomenon observed was that irreversible fouling was much less when the charge of the stabilization surfactant of O/W emulsions is opposite to the membrane. The less ceramic membrane fouling in this case was proposed to be due to a synergetic steric effect and demulsification effect which prevented the penetration of oil droplets into membrane pores and led to less pore blockage. This proposed mechanism was supported by cross section images of fouled and virgin ceramic membranes taken with scanning electron microscopy, regression results of classical fouling models, and analysis of organic components rejected by the membrane. Furthermore, this mechanism was also verified by the existence of a steric effect and demulsification effect. Our finding suggests that ceramic membrane oppositely charged to the stabilization surfactant should be applied in ultrafiltration of O/W emulsions to alleviate irreversible membrane fouling. It could be a useful rule for ceramic membrane ultrafiltration of oily wastewater. © 2015 American Chemical Society.

  10. Ceramic membrane fouling during ultrafiltration of oil/water emulsions: roles played by stabilization surfactants of oil droplets.

    Science.gov (United States)

    Lu, Dongwei; Zhang, Tao; Ma, Jun

    2015-04-07

    Oil/water (O/W) emulsion stabilized by surfactants is the part of oily wastewater that is most difficult to handle. Ceramic membrane ultrafiltration presently is an ideal process to treat O/W emulsions. However, little is known about the fouling mechanism of the ceramic membrane during O/W emulsion treatment. This paper investigated how stabilization surfactants of O/W emulsions influence the irreversible fouling of ceramic membranes during ultrafiltration. An unexpected phenomenon observed was that irreversible fouling was much less when the charge of the stabilization surfactant of O/W emulsions is opposite to the membrane. The less ceramic membrane fouling in this case was proposed to be due to a synergetic steric effect and demulsification effect which prevented the penetration of oil droplets into membrane pores and led to less pore blockage. This proposed mechanism was supported by cross section images of fouled and virgin ceramic membranes taken with scanning electron microscopy, regression results of classical fouling models, and analysis of organic components rejected by the membrane. Furthermore, this mechanism was also verified by the existence of a steric effect and demulsification effect. Our finding suggests that ceramic membrane oppositely charged to the stabilization surfactant should be applied in ultrafiltration of O/W emulsions to alleviate irreversible membrane fouling. It could be a useful rule for ceramic membrane ultrafiltration of oily wastewater.

  11. Transparent exopolymer particles (TEP) removal efficiency by a combination of coagulation and ultrafiltration to minimize SWRO membrane fouling

    KAUST Repository

    Li, Sheng; Lee, Shang-Tse; Sinha, Shahnawaz; Leiknes, TorOve; Amy, Gary L.; Ghaffour, NorEddine

    2016-01-01

    This study investigated the impact of coagulation on the transformation between colloidal and particulate transparent exopolymer particles (TEP) in seawater; and the effectiveness of a combined pretreatment consisting of coagulation and UF on minimizing TEP fouling of seawater reverse osmosis (SWRO) membranes. Coagulation with ferric chloride at pH 5 substantially transformed colloidal TEP (0.1–0.4) into particulate TEP (>0.4) leading to a better membrane fouling control. Both 50 and 100 kDa molecular weight cut-off (MWCO) UF membranes removed most of particulate and colloidal TEP without the assistance of coagulation, but coagulation is still necessary for better UF fouling control. The improvement of combined SWRO pretreatment with coagulation and 50 kDa UF membranes was not that much significant compared to UF pretreatment with 50 KDa alone. Therefore, the minimal coagulant dosage for seawater containing TEP should be based on the UF fouling control requirements rather than removal efficiency. © 2016 Elsevier Ltd

  12. Transparent exopolymer particles (TEP) removal efficiency by a combination of coagulation and ultrafiltration to minimize SWRO membrane fouling

    KAUST Repository

    Li, Sheng

    2016-07-02

    This study investigated the impact of coagulation on the transformation between colloidal and particulate transparent exopolymer particles (TEP) in seawater; and the effectiveness of a combined pretreatment consisting of coagulation and UF on minimizing TEP fouling of seawater reverse osmosis (SWRO) membranes. Coagulation with ferric chloride at pH 5 substantially transformed colloidal TEP (0.1–0.4) into particulate TEP (>0.4) leading to a better membrane fouling control. Both 50 and 100 kDa molecular weight cut-off (MWCO) UF membranes removed most of particulate and colloidal TEP without the assistance of coagulation, but coagulation is still necessary for better UF fouling control. The improvement of combined SWRO pretreatment with coagulation and 50 kDa UF membranes was not that much significant compared to UF pretreatment with 50 KDa alone. Therefore, the minimal coagulant dosage for seawater containing TEP should be based on the UF fouling control requirements rather than removal efficiency. © 2016 Elsevier Ltd

  13. Efficient Preparation of Super Antifouling PVDF Ultrafiltration Membrane with One Step Fabricated Zwitterionic Surface.

    Science.gov (United States)

    Zhao, Xinzhen; He, Chunju

    2015-08-19

    On the basis of the excellent fouling resistance of zwitterionic materials, the super antifouling polyvinylidene fluoride (PVDF) membrane was efficiently prepared though one-step sulfonation of PVDF and polyaniline blend membrane in situ. The self-doped sulfonated polyaniline (SPANI) was generated as a novel zwitterionic polymer to improve the antifouling property of PVDF ultrafiltration membrane used in sewage treatment. Surface attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, surface zeta potential, and water contact angle demonstrated the successful fabrication of zwitterionic interface by convenient sulfonation modification. The static adsorption fouling test showed the quantified adsorption mass of bovine serum albumin (BSA) pollutant on the PVDF/SPANI membrane surface decreases to 3(±2) μg/cm(2), and the water flux recovery ratio (FRR) values were no less than 95% for the three model pollutants of BSA, sodium alginate (SA), and humic acid (HA), which were corresponding hydrophobic, hydrophilic, and natural pollutants in sewage, respectively. This Research Article demonstrated the antifouling advantages of zwitterionic SPANI and aimed to provide a simple method for the large scale preparation of zwitterionic antifouling ultrafiltration membranes.

  14. Organic fouling behavior of superhydrophilic polyvinylidene fluoride (PVDF) ultrafiltration membranes functionalized with surface-tailored nanoparticles: Implications for organic fouling in membrane bioreactors

    KAUST Repository

    Liang, Shuai; Qi, Genggeng; Xiao, Kang; Sun, Jianyu; Giannelis, Emmanuel P.; Huang, Xia; Elimelech, Menachem

    2014-01-01

    This study systematically investigates the organic fouling behavior of a superhydrophilic polyvinylidene fluoride (PVDF) ultrafiltration membrane functionalized via post-fabrication tethering of surface-tailored silica nanoparticles to poly

  15. Chemical cleaning/disinfection and ageing of organic UF membranes: a review.

    Science.gov (United States)

    Regula, C; Carretier, E; Wyart, Y; Gésan-Guiziou, G; Vincent, A; Boudot, D; Moulin, P

    2014-06-01

    Membrane separation processes have become a basic unit operation for process design and product development. These processes are used in a variety of separation and concentration steps, but in all cases, the membranes must be cleaned regularly to remove both organic and inorganic material deposited on the surface and/or into the membrane bulk. Cleaning/disinfection is a vital step in maintaining the permeability and selectivity of the membrane in order to get the plant to its original capacity, to minimize risks of bacteriological contamination, and to make acceptable products. For this purpose, a large number of chemical cleaning/disinfection agents are commercially available. In general, these cleaning/disinfection agents have to improve the membrane flux to a certain extent. However, they can also cause irreversible damages in membrane properties and performances over the long term. Until now, there is considerably less literature dedicated to membrane ageing than to cleaning/disinfection. The knowledge in cleaning/disinfection efficiency has recently been improved. But in order to develop optimized cleaning/disinfection protocols there still remains a challenge to better understand membrane ageing. In order to compensate for the lack of correlated cleaning/disinfection and ageing data from the literature, this paper investigates cleaning/disinfection efficiencies and ageing damages of organic ultrafiltration membranes. The final aim is to provide less detrimental cleaning/disinfection procedures and to propose some guidelines which should have been taken into consideration in term of membrane ageing studies. To carry out this study, this article will detail the background of cleaning/disinfection and aging membrane topics in a first introductive part. In a second part, key factors and endpoints of cleaning/disinfection and aging membranes will be discussed deeply: the membrane role and the cleaning parameters roles, such as water quality, storing conditions

  16. Impact of organic fractions identified by SEC and fluorescence EEM on the hydraulic reversibility of ultrafiltration membrane fouling by secondary effluents

    KAUST Repository

    Haberkampa, Jens

    2011-05-01

    Loss of membrane filtration performance due to organic fouling is still a significant drawback for the application of low-pressure membranes in tertiary wastewater treatment. The present study investigates the relevance of different organic fractions present in secondary effluents in terms of hydraulically reversible and irreversible fouling of hollow-fibre ultrafiltration membranes. A good correlation between the hydraulically reversible filtration resistance and the total organic biopolymer concentration according to size exclusion chromatography (SEC) was observed. Qualitatively biopolymers consist mainly of polysaccharides as well as proteins with high molecular weight. Polysaccharides are retained by the membrane pores, but can be removed by simple UF backwashing. On the other hand, fluorescence excitation-emission matrix (EEM) analysis indicates that the extent of the hydraulically irreversible fouling correlates with the presence of protein-like substances. Removal of protein-like substances by biological slow sand filtration or chemical coagulation results in the significant reduction of the hydraulically irreversible fouling, which is presumably due to proteins in the molecular range of biopolymers. In contrast to the comparatively low sensitivity of colorimetric methods for the analysis of proteins and polysaccharides, the combined application of size exclusion chromatography and fluorescence EEM analysis is a promising tool for the determination of the organic fouling propensity of secondary effluents. ©2011 Desalination Publications. All rights reserved.

  17. Impact of organic fractions identified by SEC and fluorescence EEM on the hydraulic reversibility of ultrafiltration membrane fouling by secondary effluents

    KAUST Repository

    Haberkampa, Jens; Ernst, Mathias; Paar, Hendrik; Pallischeck, Daniela; Amy, Gary L.; Jekel, Martin R.

    2011-01-01

    Loss of membrane filtration performance due to organic fouling is still a significant drawback for the application of low-pressure membranes in tertiary wastewater treatment. The present study investigates the relevance of different organic fractions present in secondary effluents in terms of hydraulically reversible and irreversible fouling of hollow-fibre ultrafiltration membranes. A good correlation between the hydraulically reversible filtration resistance and the total organic biopolymer concentration according to size exclusion chromatography (SEC) was observed. Qualitatively biopolymers consist mainly of polysaccharides as well as proteins with high molecular weight. Polysaccharides are retained by the membrane pores, but can be removed by simple UF backwashing. On the other hand, fluorescence excitation-emission matrix (EEM) analysis indicates that the extent of the hydraulically irreversible fouling correlates with the presence of protein-like substances. Removal of protein-like substances by biological slow sand filtration or chemical coagulation results in the significant reduction of the hydraulically irreversible fouling, which is presumably due to proteins in the molecular range of biopolymers. In contrast to the comparatively low sensitivity of colorimetric methods for the analysis of proteins and polysaccharides, the combined application of size exclusion chromatography and fluorescence EEM analysis is a promising tool for the determination of the organic fouling propensity of secondary effluents. ©2011 Desalination Publications. All rights reserved.

  18. Polypropylene Track Membranes for Mikro and Ultrafiltration of Chemically Aggressive Agents

    CERN Document Server

    Kravets, L I; Apel, P Yu

    2000-01-01

    A production process for track membranes on the basis of chemically resistant polymer polypropylene has been developed. Research in all stages of the formation of the polypropylene track membranes has been conducted: the main principles of the process of chemical etching of polypropylene irradiated with accelerated ions have been investigated, the most effective structure of the etchant for a selective etching of the heavy ion tracks has been selected, the parameters of etching have been optimized. A method for sensibilization of latent tracks in polypropylene by effect of solvents has been developed. It helps to reach a significant increase in etching selectivity. A method for destruction of an absorbed chromocontaining layer on the surface of polypropylene track membranes formed during etching has been elaborated. Experimental samples of the membranes for micro and ultrafiltration have been obtained and their properties have been studied in course of their exploitation in chemically aggressive agents. For t...

  19. Treatment of cosmetic effluent in different configurations of ceramic UF membrane based bioreactor: Toxicity evaluation of the untreated and treated wastewater using catfish (Heteropneustes fossilis).

    Science.gov (United States)

    Banerjee, Priya; Dey, Tanmoy Kumar; Sarkar, Sandeep; Swarnakar, Snehasikta; Mukhopadhyay, Aniruddha; Ghosh, Sourja

    2016-03-01

    Extensive usage of pharmaceutical and personal care products (PPCPs) and their discharge through domestic sewage have been recently recognized as a new generation environmental concern which deserves more scientific attention over the classical environmental pollutants. The major issues of this type of effluent addressed in this study were its colour, triclosan and anionic surfactant (SDS) content. Samples of cosmetic effluent were collected from different beauty treatment salons and spas in and around Kolkata, India and treated in bioreactors containing a bacterial consortium isolated from activated sludge samples collected from a common effluent treatment plant. Members of the consortium were isolated and identified as Klebsiella sp., Pseudomonas sp., Salmonella sp. and Comamonas sp. The biotreated effluent was subjected to ultrafiltration (UF) involving indigenously prepared ceramic membranes in both side-stream and submerged mode. Analysis of the MBR treated effluent revealed 99.22%, 98.56% and 99.74% removal of colour, triclosan and surfactant respectively. Investigation of probable acute and chronic cyto-genotoxic potential of the untreated and treated effluents along with their possible participation in triggering oxidative stress was carried out with Heteropneustes fossilis (Bloch). Comet formation recorded in both liver and gill cells and micronucleus count in peripheral erythrocytes of individuals exposed to untreated effluent increased with duration of exposure and was significantly higher than those treated with UF permeates which in turn neared control levels. Results of this study revealed successful application of the isolated bacterial consortium in MBR process for efficient detoxification of cosmetic effluent thereby conferring the same suitable for discharge and/or reuse. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Optimizing UF Cleaning in UF-SWRO System Using Red Sea Water

    KAUST Repository

    Bahshwan, Mohanad

    2012-07-01

    Increasing demand for fresh water in arid and semi-arid areas, similar to the Middle East, pushed for the use of seawater desalination techniques to augment freshwater. Seawater Reverse Osmosis (SWRO) is one of the techniques that have been commonly used due to its cost effectiveness. Recently, the use of Ultrafiltration (UF) was recommended as an effective pretreatment for SWRO membranes, as opposed to conventional methods (i.e. sand filtration). During UF operation, intermittent cleaning is required to remove particles and contaminants from the membrane\\'s surface and pores. The different cleaning steps consume chemicals and portion of the product water, resulting in a decrease in the overall effectiveness of the process and hence an increase in the production cost. This research focused on increasing the plant\\'s efficiency through optimizing the cleaning protocol without jeopardizing the effectiveness of the cleaning process. For that purpose, the design of experiment (DOE) focused on testing different combinations of these cleaning steps while all other parameters (such as filtration flux or backwash flux) remained constant. The only chemical used was NaOCI during the end of each experiment to restore the trans-membrane pressure (TMP) to its original state. Two trains of Dow™ Ultrafiltration SFP-2880 were run in parallel for this study. The first train (named UF1) was kept at the manufacturer\\'s recommended cleaning steps and frequencies, while the second train (named UF2) was varied according to the DOE. The normalized final TMP was compared to the normalized initial TMP to measure the fouling rate of the membrane at the end of each experiment. The research was supported by laboratory analysis to investigate the cause of the error in the data by analyzing water samples collected at different locations. Visual inspection on the results from the control unit showed that the data cannot be reproduced with the current feed water quality. Statistical analysis

  1. Size enlargement of radioactive and hazardous species and their separation by microfiltration and ultrafiltration membranes

    International Nuclear Information System (INIS)

    Vijayan, S.; Wong, C.F.; Buckley, L.P.

    1993-01-01

    Separation and volume reduction of aqueous solutions involving membranes is evolving into an expanding and diversified field. Numerous commercially successful membranes and their applications are now available. Among different driving forces used in membrane separation, pressure-driven separation has gained wide application. Depending on the size of the dissolved species in solution to be separated, the pressure needed to achieve the desired separation varies. The microfiltration and ultrafiltration membrane systems are low-pressure processes that generally operate below 350 kPa. To exploit these membranes in applications involving the removal of dissolved contaminants from solutions, it is essential to create a suitable size for the dissolved contaminants, so that the membranes can effectively retain them while producing a filtrate stream essentially free of contaminants. Size enlargement of the dissolved contaminants can be achieved through solution conditioning with the addition of one or a combination of chemical reagents and powdered materials. Examples of typical additives include: pH chemicals, polyelectrolytes, microorganisms and powdered adsorption/ion-exchange materials. In many situations, adequate control and optimization of the system chemistry and hydraulic conditions provide high selectivity and efficiency for contaminant removal. This paper summarizes removal efficiency data for cadmium, lead, mercury, uranium, arsenic, strontium-90/85, cesium-137 and iron. These data resulted from various initiatives on membrane technology undertaken during the past five years by the Waste Processing Technology group at Chalk River Laboratories. The technology involves size enlargement of contaminants present in waste solution, and their separation using either microfiltration or ultrafiltration. The data support remedial applications involving treatment of contaminated groundwater and soils

  2. Plasma deposition of silver nanoparticles on ultrafiltration membranes: antibacterial and anti-biofouling properties.

    Science.gov (United States)

    Cruz, Mercedes Cecilia; Ruano, Gustavo; Wolf, Marcus; Hecker, Dominic; Vidaurre, Elza Castro; Schmittgens, Ralph; Rajal, Verónica Beatriz

    2015-02-01

    A novel and versatile plasma reactor was used to modify Polyethersulphone commercial membranes. The equipment was applied to: i) functionalize the membranes with low-temperature plasmas, ii) deposit a film of poly(methyl methacrylate) (PMMA) by Plasma Enhanced Chemical Vapor Deposition (PECVD) and, iii) deposit silver nanoparticles (SNP) by Gas Flow Sputtering. Each modification process was performed in the same reactor consecutively, without exposure of the membranes to atmospheric air. Scanning electron microscopy and transmission electron microscopy were used to characterize the particles and modified membranes. SNP are evenly distributed on the membrane surface. Particle fixation and transport inside membranes were assessed before- and after-washing assays by X-ray photoelectron spectroscopy depth profiling analysis. PMMA addition improved SNP fixation. Plasma-treated membranes showed higher hydrophilicity. Anti-biofouling activity was successfully achieved against Gram-positive ( Enterococcus faecalis ) and -negative ( Salmonella Typhimurium) bacteria. Therefore, disinfection by ultrafiltration showed substantial resistance to biofouling. The post-synthesis functionalization process developed provides a more efficient fabrication route for anti-biofouling and anti-bacterial membranes used in the water treatment field. To the best of our knowledge, this is the first report of a gas phase condensation process combined with a PECVD procedure in order to deposit SNP on commercial membranes to inhibit biofouling formation.

  3. Biodegradation behavior of natural organic matter (NOM) in a biological aerated filter (BAF) as a pretreatment for ultrafiltration (UF) of river water

    KAUST Repository

    Huang, Guocheng; Meng, Fangang; Zheng, Xing; Wang, Yuan; Wang, Zhigang; Liu, Huijun; Jekel, Martin R.

    2011-01-01

    In this study, biodegradation of natural organic matter (NOM) in a biological aerated filter (BAF) as pretreatment of UF treating river water was investigated. Photometric measurement, three-dimensional excitation-emission matrix (EEM) fluorescence

  4. Enhanced permeability and antifouling performance of cellulose acetate ultrafiltration membrane assisted by l-DOPA functionalized halloysite nanotubes.

    Science.gov (United States)

    Mu, Keguang; Zhang, Dalun; Shao, Ziqiang; Qin, Dujian; Wang, Yalong; Wang, Shuo

    2017-10-15

    l-Dopa functionalized halloysite nanotubes (HNTs) were prepared by the self-polymerization of l-dopa in the weak alkaline condition. Then different contents of l-dopa coated HNTs (LPDHNTs) were blended into cellulose acetate to prepare enhanced performance ultrafiltration membranes via the phase inversion method. The HNTs and LPDHNTs were characterized by FTIR, XPS, and TEM anysis. And the membranes morphologies, separation performance, antifouling performance, mechanical properties and hydrophilicity were also investigated. It was found that the composite membranes exhibited excellent antifouling performance. The pure water flux of 3.0wt% LPDHNTs/CA membrane increased from 11.4Lm -2 h -1 to 92.9Lm -2 h -1 , while the EA rejection ratio of the membrane was about 91.2%. In addition, the mechanical properties of the resultant membranes were strengthened compared with the CA ultrafiltration membrane. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. A simple fabrication of plasmonic surface-enhanced Raman scattering (SERS) substrate for pesticide analysis via the immobilization of gold nanoparticles on UF membrane

    Science.gov (United States)

    Hong, Jangho; Kawashima, Ayato; Hamada, Noriaki

    2017-06-01

    In this study, we developed a facile fabrication method to access a highly reproducible plasmonic surface enhanced Raman scattering substrate via the immobilization of gold nanoparticles on an Ultrafiltration (UF) membrane using a suction technique. This was combined with a simple and rapid analyte concentration and detection method utilizing portable Raman spectroscopy. The minimum detectable concentrations for aqueous thiabendazole standard solution and thiabendazole in orange extract are 0.01 μg/mL and 0.125 μg/g, respectively. The partial least squares (PLS) regression plot shows a good linear relationship between 0.001 and 100 μg/mL of analyte, with a root mean square error of prediction (RMSEP) of 0.294 and a correlation coefficient (R2) of 0.976 for the thiabendazole standard solution. Meanwhile, the PLS plot also shows a good linear relationship between 0.0 and 2.5 μg/g of analyte, with an RMSEP value of 0.298 and an R2 value of 0.993 for the orange peel extract. In addition to the detection of other types of pesticides in agricultural products, this highly uniform plasmonic substrate has great potential for application in various environmentally-related areas.

  6. Experimental and computational investigation of polyacrylonitrile ultrafiltration membrane for industrial oily wastewater treatment

    International Nuclear Information System (INIS)

    Adib Hooman; Hassanajili, Shadi; Sheikhi-Kouhsar, Mohammad Reza; Salahi, Abdolhamid; Mohammadi, Toraj

    2015-01-01

    An experimental study on separation of industrial oil from oily wastewater has been done. A polyacrylonitrile membrane with a molecular weight cut-off (MWCO) of 20 kDa was used and an outlet wastewater of API unit of Tehran refinery was employed. The main purpose of this study was to develop a support vector machine model for permeation flux decline and fouling resistance in a cross-flow hydrophilic polyacrylonitrile membrane during ultrafiltration. The operating conditions which have been applied to develop a support vector machine model were transmembrane pressure (TMP), operating temperature, cross flow velocity (CFV), pH values of oily wastewater, permeation flux decline and fouling resistance. The testing results obtained by the support vector machine models are in very good agreement with experimental data. The calculated squared correlation coefficients for permeation flux decline and fouling resistance were both 0.99. Based on the results, the support vector machine proved to be a reliable accurate estimation method

  7. Experimental and computational investigation of polyacrylonitrile ultrafiltration membrane for industrial oily wastewater treatment

    Energy Technology Data Exchange (ETDEWEB)

    Adib Hooman; Hassanajili, Shadi; Sheikhi-Kouhsar, Mohammad Reza [Shiraz University, Shiraz (Iran, Islamic Republic of); Salahi, Abdolhamid; Mohammadi, Toraj [Iran University of Science and Technology (IUST), Tehran (Iran, Islamic Republic of)

    2015-01-15

    An experimental study on separation of industrial oil from oily wastewater has been done. A polyacrylonitrile membrane with a molecular weight cut-off (MWCO) of 20 kDa was used and an outlet wastewater of API unit of Tehran refinery was employed. The main purpose of this study was to develop a support vector machine model for permeation flux decline and fouling resistance in a cross-flow hydrophilic polyacrylonitrile membrane during ultrafiltration. The operating conditions which have been applied to develop a support vector machine model were transmembrane pressure (TMP), operating temperature, cross flow velocity (CFV), pH values of oily wastewater, permeation flux decline and fouling resistance. The testing results obtained by the support vector machine models are in very good agreement with experimental data. The calculated squared correlation coefficients for permeation flux decline and fouling resistance were both 0.99. Based on the results, the support vector machine proved to be a reliable accurate estimation method.

  8. Development of High-Antifouling PPSU Ultrafiltration Membrane by Using Compound Additives: Preparation, Morphologies, and Filtration Resistant Properties

    OpenAIRE

    Jie Liu; Zhencheng Zhong; Rui Ma; Weichen Zhang; Jiding Li

    2016-01-01

    In this study, flat sheet asymmetric polyphenylsulfone (PPSU) ultrafiltration membranes with enhanced antifouling properties were prepared with a non-solvent induced phase separation (NIPS) method through compound additives containing a polymeric pore-forming agent, a small molecular non-solvent and a surfactant. The formation processes of the porous asymmetric membranes with different kinds of additives were studied in detail, and the microstructure controllable preparation of membrane was a...

  9. Increasing Water System Efficiency with Ultrafiltration Pre-treatment in Power Plants

    International Nuclear Information System (INIS)

    Majamaa, Katariina; Suarez, Javier; Gasia Eduard

    2012-09-01

    Water demineralization with reverse osmosis (RO) membranes has a long and successful history in water treatment for power plants. As the industry strives for more efficient, reliable and compact water systems, pressurized hollow-fiber ultrafiltration (UF) has become an increasingly appealing pre-treatment technology. Compared to conventional, non- membrane based pretreatments, ultrafiltration offers higher efficiency in the removal of suspended solids, microorganisms and colloidal matter, which are all common causes for operational challenges experienced in the RO systems. In addition, UF is more capable of handling varying feed water qualities and removes the risk of particle carry-over often seen with conventional filtration techniques. Ultrafiltration is a suitable treatment technology for various water types from surface waters to wastewater, and the more fluctuating or challenging the feed water source is, the better the benefits of UF are seen compared to conventional pretreatments. Regardless of the feed water type, ultrafiltration sustains a constant supply of high quality feed water to downstream RO, allowing a more compact and cost efficient RO system design with improved operational reliability. A detailed focus on the design and operational aspects and experiences of two plants is provided. These examples demonstrate both economical UF operation and tangible impact of RO process improvement. Experience from these plants can be leveraged to new projects. (authors)

  10. Ultrafiltration membranes from waste polyethylene terephthalate and additives: synthesis and characterization

    Directory of Open Access Journals (Sweden)

    Smitha Rajesh

    2014-01-01

    Full Text Available The synthesis and characterization of asymmetric ultrafiltration membranes from recycled polyethylene terephthalate (PET and polyvinylpyrrolidone (PVP is reported. PET is currently used in many applications, including the manufacture of bottles and tableware. Monomer extraction from waste PET is expensive, and this process has not yet been successfully demonstrated on a viable scale. Hence, any method to recycle or regenerate PET once it has been used is of significant importance from scientific and environmental research viewpoints. Such a process would be a green alternative due to reduced raw monomer consumption and the additional benefit of reduced manufacturing costs. The membranes described here were prepared by a phase-inversion process, which involved casting a solution containing PET, m-cresol as solvent, and polyethylene glycol (PEG of different molecular weights as additives. The membranes were characterized in terms of pure water permeability (PWP, molecular weight cut-off (MWCO, and flux and membrane morphology. The results show that the addition of PEG with high molecular weights leads to membranes with higher PWP. The presence of additives affects surface roughness and membrane morphology.

  11. A feasibility study of ultrafiltration/reverse osmosis (UF/RO)-based wastewater treatment and reuse in the metal finishing industry

    DEFF Research Database (Denmark)

    Petrinic, Irena; Korenak, Jasmina; Povodnik, Damijan

    2015-01-01

    that the ultrafiltration-reverse osmosis treatment removed between 91.3% and 99.8% of the contaminants from the effluent, such as metal elements, organic, and inorganic compounds. Contaminants such as suspended solids, nickel, ammonium nitrogen, sulphate nitrogen, chemical oxygen demand, and biochemical oxygen demand were...... completely removed, the concentrations in the permeate being under the detection limits, thus the quality of the ultrafiltration-reverse osmosis process met the reuse criteria. This demonstrates the technological feasibility of wastewater reuse during electro-plating processes and the pre-treatment of powder...

  12. Study to determine the technical and economic feasibility of reclaiming chemicals used in micellar polymer and low tension surfactant flooding. Final report. [Ultrafiltration membranes and reverse osmosis membranes

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, R.H.; Himmelblau, A.; Donnelly, R.G.

    1978-02-01

    Energy Resources Company has developed a technology for use with enhanced oil recovery to achieve emulsion breaking and surfactant recovery. By using ultrafiltration membranes, the Energy Resources Company process can dewater an oil-in-water type emulsion expected from enhanced oil recovery projects to the point where the emulsion can be inverted and treated using conventional emulsion-treating equipment. By using a tight ultrafiltration membrane or a reverse osmosis membrane, the Energy Resources Company process is capable of recovering chemicals such as surfactants used in micellar polymer flooding.

  13. Morphology and performance of polyvinylidene fluoride/perfluoro sulphonic acid hollow fiber ultrafiltration blend membranes

    International Nuclear Information System (INIS)

    Yuan, Guo-Lin; Xu, Zhen-Liang; Wei, Yong-Ming; Yu, Li-Yun

    2009-01-01

    Polyvinylidene fluoride-perfluoro sulphonic acid hollow fibre ultrafiltration blend membranes were prepared by wet-spinning method. Polyvinylpyrrolidone and ethanol aqueous solutions were employed as additive and coagulants, respectively. The effect of Polyvinylpyrrolidone concentration in the dopes and ethanol concentration in the coagulants on morphology and performance of Polyvinylidene fluoride -perfluoro sulphonic acid hollow fibre ultrafiltration blend membranes were investigated. Blend membranes were characterized in terms of precipitation kinetics, morphology, thermal property and separation performance. The results showed that the increments of Polyvinylpyrrolidone concentration in the dopes and ethanol concentration in coagulants both resulted in higher pure water permeation flux and worse rejection (R) of bovine serum albumin (with the increment of Polyvinylpyrrolidone concentration from 0 to 5 wt% in the dopes, pure water permeation increased from 41.7 L.m -2 .h -1 to 134 L.m -2 .h -1 and R decreased from 99.8% to 84.4% as well as with the increase in ethanol concentration in coagulants from 0 to 40 wt%, pure water permeation increased from 33.5 L.m -2 .h- 1 to 123 L.m -2 .h -1 and R decreased from 97.7% to 88.7%). However, the proportion of sponge-like structure in the cross-section of membranes decreased with the increasing Polyvinylpyrrolidone concentration in the dopes and the proportion increased with the increased ethanol concentration in the coagulations. In addition, the location of the sponge-like structure in the cross-section of membranes was significantly influenced by ethanol concentrations in the coagulants and differential scanning calorimeter results revealed that the crystallinity (X c ) of the blend membrane was in accordance with the proportion of sponge-like structure. These behaviours were attributed to the different roles of Polyvinylpyrrolidone in the dopes and ethanol in the coagulants, respectively. Polyvinylidene fluoride

  14. A Review of Ultrafiltration and Forward Osmosis:application and modification

    Science.gov (United States)

    Chao, Gong; Shuili, Yu; Yufei, Shangguan; Zhengyang, Gu; Wangzhen, Yang; Liumo, Ren

    2018-03-01

    As a new treatment, membrane filtration is playing a more prominent role in treating many kinds of wastewater. Among all the membrane technologies, ultrafiltration(UF) and forward osmosis(FO) technology has been widely utilized and developed in oil field and refinery produced water. However, the reports about the differences between the two kinds of membrane technology used in oily wastewater are not yet available. In this review, at first we introduce the advantages, shortcomings and applications of UF and FO membranes. Among these, we mainly illustrate the membrane fouling, which now is a big problem because it increases costs and decreases membrane life to limit the industrialization of the membrane, and the different modification methods of membranes are discussed to figure out how these ways can ease the membrane fouling. Next we make a comparison of the two membranes. Finally we illustrate the future research topics.

  15. Characterization and utilization of the permeate and retentate obtained after “dead-end” ultrafiltration

    Directory of Open Access Journals (Sweden)

    Vasić Vesna M.

    2013-01-01

    Full Text Available In the recent years, with the increase in bioethanol production, the increasing amounts of distillery wastewater are generated. Such wastewater (stillage is one of the most polluted waste product of the food and beverage industries. The present study evaluates the treatment of distillery wastewater by ultrafiltration (UF, in order to reduce its pollution and evaluate the composition of the permeate and retentate. Polyethersulfone ultrafiltration membrane with molecular weight cut-off (MWCO 30000 Da, was used for the experiments. The UF was carried out in dead-end mode. The results of the analyses of the permeate and retentate obtained after ultrafiltration were considered as well as different ways for their further utilization. The pollutant level in the permeate was decreased significantly in comparison to the raw stillage, and suspended solids were completely removed from the stillage. [Projekat Ministarstva nauke Republike Srbije, br. TR 31002

  16. Effect of operating conditions on the performances of multichannel ceramic UF membranes for textile mercerization wastewater treatment.

    Science.gov (United States)

    Zebić Avdičević, Maja; Košutić, Krešimir; Dobrović, Slaven

    2017-01-01

    Textile wastewaters are rated as one of the most polluting in all industrial sectors, and membrane separation is the most promising technology for their treatment and reuse of auxiliary chemicals. This study evaluates the performance of three types of tubular ceramic ultrafiltration membranes differing by mean pore size (1, 2 and 500 kDa) treating textile mercerization wastewater from a textile mill at different operating conditions: cross-flow velocity (CFV) and temperature. Acceptable results were obtained with 1 kDa ceramic membrane, with rejection efficiencies 92% for suspended solids, 98% for turbidity, 98% for color and 53% for total organic carbon at 20°C and 3 m s -1 CFV. Highest fouling effect was observed for 500 kDa membrane and lowest CFV. According to the observed results, 1 kDa membrane could be used for the treatment of wastewater from the textile mercerization process in terms of permeate quality.

  17. Biodegradation behavior of natural organic matter (NOM) in a biological aerated filter (BAF) as a pretreatment for ultrafiltration (UF) of river water

    KAUST Repository

    Huang, Guocheng

    2011-04-15

    In this study, biodegradation of natural organic matter (NOM) in a biological aerated filter (BAF) as pretreatment of UF treating river water was investigated. Photometric measurement, three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy and liquid chromatography with online organic carbon detector (LC-OCD) were used to investigate the fate of NOM fractions in the BAF+UF process. Results showed that the BAF process could effectively remove particles and parts of dissolved organic matter, which led to a lower NOM loading in the UF system, but different NOM fractions showed different biodegradation potentials. Further biodegradation batch experiments confirmed this observation and identified that polysaccharides and proteins (quantified using photometric methods) contained a large proportion of readily biodegradable matter while humic substances were mainly composed of inert organic substances. According to EEM measurements, it is evident that protein-like substances were more readily eliminated by microorganisms than humic-like substances. LC-OCD data also supported the phenomena that the polysaccharides and large-size proteins were more degradable than humic substances. © 2011 Springer-Verlag.

  18. Antioxidant activities of bambara groundnut (Vigna subterranea) protein hydrolysates and their membrane ultrafiltration fractions.

    Science.gov (United States)

    Arise, Abimbola K; Alashi, Adeola M; Nwachukwu, Ifeanyi D; Ijabadeniyi, Oluwatosin A; Aluko, Rotimi E; Amonsou, Eric O

    2016-05-18

    In this study, the bambara protein isolate (BPI) was digested with three proteases (alcalase, trypsin and pepsin), to produce bambara protein hydrolysates (BPHs). These hydrolysates were passed through ultrafiltration membranes to obtain peptide fractions of different sizes (fractions were investigated for antioxidant activities. The membrane fractions showed that peptides with sizes 3 kDa. This is in agreement with the result obtained for the ferric reducing power, metal chelating and hydroxyl radical scavenging activities where higher molecular weight peptides exhibited better activity (p fractions. However, for all the hydrolysates, the low molecular weight peptides were more effective diphenyl-1-picrylhydrazyl (DPPH) radical scavengers but not superoxide radicals when compared to the bigger peptides. In comparison with glutathione (GSH), BPHs and their membrane fractions had better (p fractions that did not show any metal chelating activity. However, the 5-10 kDa pepsin hydrolysate peptide fractions had greater (88%) hydroxyl scavenging activity than GSH, alcalase and trypsin hydrolysates (82%). These findings show the potential use of BPHs and their peptide fraction as antioxidants in reducing food spoilage or management of oxidative stress-related metabolic disorders.

  19. Pre-treatment and membrane ultrafiltration using treated palm oil mill effluent (POME

    Directory of Open Access Journals (Sweden)

    Wong Pui Wah

    2002-11-01

    Full Text Available Treatment of palm oil mill effluent (POME has always been a topic of research in Malaysia. This effluent that is extremely rich in organic content needs to be properly treated to minimize environmental hazards before it is released into watercourses. The common practice for treating POME in Malaysia involves a combination of aerobic and anaerobic methods. The purpose of tertiary treatment is to allow the treated water to be reused in the mill operations for other purposes such as feed water. The proposed treatment will also ensure the industry to meet a more stringent discharge standard in terms of the BOD, COD and nitrogen values. In this study membrane ultrafiltration is used as the tertiary treatment method. Before the actual membrane operation was conducted, the samples were pre-treated using three separate method namely filtration, centrifugation and coagulation. It was found that the combination of filtrationultrafiltration treatment POME produced the best-treated sample quality in terms of pollutant contents elimination, namely % BOD, % COD and % nitrogen removal.

  20. Measurements of serum-free thyroid hormone concentrations by ultrafiltration

    International Nuclear Information System (INIS)

    Konno, Norimichi; Hagiwara, Kohji; Taguchi, Hideo; Murakami, Shigeki; Taguchi, Shizuko

    1987-01-01

    An ultrafiltration method (UF) for measuring free thyroxine (FT 4 ) and free triiodothyronine (FT 3 ) using the Diaflow YM membrane (Centricon-10) is described. The results are compared with those by equilibrium dialysis (ED) and also by mathematical calculations derived from T 4 , T 3 , and binding protein concentrations. The precision with the UF method was excellent. The normal ranges of FT 4 and FT 3 by the three methods are all comparable. There was a high degree of correlation of FT 4 or FT 3 results by UF with those by ED and by calculation (r = 0.940 - 0.974, n = 161, P 4 and FT 3 by all methods agreed well for hyperthyroidism, hypothyroidism, and for patients with low T 4 -binding globulin. The mean FT 3 in pregnancy was lower than the normal value for all methods, and FT 4 concentrations by UF and calculation also decreased in late pregnancy. The mean FT 4 by UF and ED in low T 3 syndrome were significantly higher than in the normal controls, while the calculated FT 4 was lower. The FT 3 in low T 3 syndrome distributed normal to subnormal in all methods. These results indicate that a) the UF method is a reliable reference method for measuring FT 4 and FT 3 concentrations; b) the UF results agree well with those by ED and also with theoretically derived values in subjects with thyroid diseases and TBG abnormalities; c) for patients with low T 3 syndrome, the FT 4 results obtained by UF and ED are similarly discrepant from the calculated results, implying the existence of binding inhibitor(s) which affect both UF and ED measurements. (author)

  1. Evaluation of ultrafiltration membranes for treating low-level radioactive contaminated liquid waste

    International Nuclear Information System (INIS)

    Koenst, J.W.; Roberts, R.C.

    1978-01-01

    A series of experiments were performed on Waste Disposal Facility (WD) influent using Romicon hollow fiber ultrafiltration modules with molecular weight cutoffs ranging from 2000 to 80,000. The rejection of conductivity was low in most cases. The rejection of radioactivity ranged from 90 to 98%, depending on the membrane type and on the feed concentration. Typical product activity ranged from 7 to 100 dis/min/ml of alpha radiation. Experiments were also performed on alpha-contaminated laundry wastewater. Results ranged from 98 to >99.8%, depending on the membrane type. This yielded a product concentration of less than 0.1 dis/min/ml of alpha radiation. Tests on PP-Building decontamination water yielded rejections of 85 to 88% alpha radiation depending on the membrane type. These experiments show that the ability to remove radioactivity by membrane is a function of the contents of the waste stream because the radioactivity in the wastewater is in various forms: ionic, polymeric, colloidal, and absorbed onto suspended solids. Although removal of suspended or colloidal material is very high, removal of ionic material is not as effective. Alpha-contaminated laundry wastewater proved to be the easiest to decontaminate, whereas the low-level PP-Building decontamination water proved to be the most difficult to decontaminate. Decontamination of the WD influent, a combined waste stream, varied considerably from day to day because of its constantly changing makeup. The WD influent was also treated with various substances, such as polyelectrolytes, complexing agents, and coagulants, to determine if these additives would aid in the removal of radioactive material from the various wastewaters by complexing the ionic species. At the present time, none of the additives evaluated has had much effect; but experiments are continuing

  2. Preparation and characterization of a novel PVDF ultrafiltration membrane by blending with TiO_2-HNTs nanocomposites

    International Nuclear Information System (INIS)

    Zeng, Guangyong; He, Yi; Yu, Zongxue; Zhan, Yingqing; Ma, Lan; Zhang, Lei

    2016-01-01

    Highlights: • A novel TiO_2-HNTs/PVDF ultrafiltration membrane was prepared. • TiO_2 dispersed well in membrane matrix by loading on the surface of HNTs. • The hydrophilicity of membrane was improved with the addition of TiO_2-HNTs. • TiO_2-HNTs/PVDF membranes showed good antifouling performance. - Abstract: Novel polyvinylidene fluoride (PVDF) ultrafiltration membranes were prepared by blending with different contents of titanium dioxide-halloysite nanotubes (TiO_2-HNTs) composites into the PVDF matrix. The effects of TiO_2-HNTs content on the membrane performances, such as hydrophilicity, rejection ratio and antifouling properties were investigated in detail. X-ray diffraction (XRD), thermo-gravimetric analyzer (TGA) and scanning electron microscope (SEM) analyses showed that TiO_2 was loaded on the surface of HNTs successfully and homogeneously by sol-gel method. The morphologies and microstructure of the membranes were characterized by SEM and atomic force microscopy (AFM). The contact angle (CA) tests indicated that the hydrophilicity of membranes was significantly increased with the addition of TiO_2-HNTs. The pure water flux of 3%TiO_2-HNTs/PVDF was increased by 264.8% and 35.6%, respectively, compared with pure PVDF membrane and 3%TiO_2/PVDF membrane, although the rejection of bovine serum albumin (BSA) was slightly decreased. More importantly, TiO_2-HNTs/PVDF membrane exhibited an excellent anti-fouling performance, which was attributed to the hydrophobic contaminants being resisted by hydrophilic nanoparticles. It can be expected that this work may provide some references to solve the dispersion of nanoparticle in the membrane and improve the anti-fouling performance of membrane in the field of wastewater treatment.

  3. Preparation and characterization of a novel PVDF ultrafiltration membrane by blending with TiO{sub 2}-HNTs nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Guangyong [College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); He, Yi, E-mail: heyi@swpu.edu.cn [College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); State Key Laboratory of Oil & Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); Yu, Zongxue; Zhan, Yingqing; Ma, Lan [College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); Zhang, Lei, E-mail: zgc166929@sohu.com [College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu, Sichuan 610500 (China); Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province, Southwest Petroleum University, Chengdu, Sichuan 610500 (China)

    2016-05-15

    Highlights: • A novel TiO{sub 2}-HNTs/PVDF ultrafiltration membrane was prepared. • TiO{sub 2} dispersed well in membrane matrix by loading on the surface of HNTs. • The hydrophilicity of membrane was improved with the addition of TiO{sub 2}-HNTs. • TiO{sub 2}-HNTs/PVDF membranes showed good antifouling performance. - Abstract: Novel polyvinylidene fluoride (PVDF) ultrafiltration membranes were prepared by blending with different contents of titanium dioxide-halloysite nanotubes (TiO{sub 2}-HNTs) composites into the PVDF matrix. The effects of TiO{sub 2}-HNTs content on the membrane performances, such as hydrophilicity, rejection ratio and antifouling properties were investigated in detail. X-ray diffraction (XRD), thermo-gravimetric analyzer (TGA) and scanning electron microscope (SEM) analyses showed that TiO{sub 2} was loaded on the surface of HNTs successfully and homogeneously by sol-gel method. The morphologies and microstructure of the membranes were characterized by SEM and atomic force microscopy (AFM). The contact angle (CA) tests indicated that the hydrophilicity of membranes was significantly increased with the addition of TiO{sub 2}-HNTs. The pure water flux of 3%TiO{sub 2}-HNTs/PVDF was increased by 264.8% and 35.6%, respectively, compared with pure PVDF membrane and 3%TiO{sub 2}/PVDF membrane, although the rejection of bovine serum albumin (BSA) was slightly decreased. More importantly, TiO{sub 2}-HNTs/PVDF membrane exhibited an excellent anti-fouling performance, which was attributed to the hydrophobic contaminants being resisted by hydrophilic nanoparticles. It can be expected that this work may provide some references to solve the dispersion of nanoparticle in the membrane and improve the anti-fouling performance of membrane in the field of wastewater treatment.

  4. Effects of Bloom-Forming Algae on Fouling of Integrated Membrane Systems in Seawater Desalination

    Science.gov (United States)

    Ladner, David Allen

    2009-01-01

    Combining low- and high-pressure membranes into an integrated membrane system is an effective treatment strategy for seawater desalination. Low-pressure microfiltration (MF) and ultrafiltration (UF) membranes remove particulate material, colloids, and high-molecular-weight organics leaving a relatively foulant-free salt solution for treatment by…

  5. Hydraulically irreversible fouling on ceramic MF/UF membranes: comparison of fouling indices, foulant composition and irreversible pore narrowing

    KAUST Repository

    Shang, Ran

    2015-05-06

    The application of ceramic membranes in water treatment is becoming increasing attractive because of their long life time and excellent chemical, mechanical and thermal stability. However, fouling of ceramic membranes, especially hydraulically irreversible fouling, is still a critical aspect affecting the operational cost and energy consumption in water treatment plants. In this study, four ceramic membranes with pore sizes or molecular weight cut-off (MWCO) of 0.20 μm, 0.14 μm, 300 kDa and 50 kDa were compared during natural surface water filtration with respect to hydraulically irreversible fouling index (HIFI), foulant composition and narrowing of pore size due to the irreversible fouling. Our results showed that the hydraulically irreversible fouling index (HIFI) was proportional to the membrane pore size (r2=0.89) when the same feed water was filtrated. The UF membranes showed lower HIFI values than the MF membranes. Pore narrowing (internal fouling) was found to be a main fouling pattern of the hydraulically irreversible fouling. The internal fouling was caused by monolayer adsorption of foulants with different sizes that is dependent on the size of the membrane pore.

  6. Hydraulically irreversible fouling on ceramic MF/UF membranes: comparison of fouling indices, foulant composition and irreversible pore narrowing

    KAUST Repository

    Shang, Ran; Vuong, Francois; Hu, Jingyi; Li, Sheng; Kemperman, Antoine J.B.; Nijmeijer, Kitty; Cornelissen, Emile R.; Heijman, Sebastiaan G.J.; Rietveld, Luuk C.

    2015-01-01

    The application of ceramic membranes in water treatment is becoming increasing attractive because of their long life time and excellent chemical, mechanical and thermal stability. However, fouling of ceramic membranes, especially hydraulically irreversible fouling, is still a critical aspect affecting the operational cost and energy consumption in water treatment plants. In this study, four ceramic membranes with pore sizes or molecular weight cut-off (MWCO) of 0.20 μm, 0.14 μm, 300 kDa and 50 kDa were compared during natural surface water filtration with respect to hydraulically irreversible fouling index (HIFI), foulant composition and narrowing of pore size due to the irreversible fouling. Our results showed that the hydraulically irreversible fouling index (HIFI) was proportional to the membrane pore size (r2=0.89) when the same feed water was filtrated. The UF membranes showed lower HIFI values than the MF membranes. Pore narrowing (internal fouling) was found to be a main fouling pattern of the hydraulically irreversible fouling. The internal fouling was caused by monolayer adsorption of foulants with different sizes that is dependent on the size of the membrane pore.

  7. Organic micro-pollutants’ removal via anaerobic membrane bioreactor with ultrafiltration and nanofiltration

    KAUST Repository

    Wei, Chunhai

    2015-12-15

    The removal of 15 organic micro-pollutants (OMPs) in synthetic municipal wastewater was investigated in a laboratory-scale mesophilic anaerobic membrane bioreactor (AnMBR) using ultrafiltration and AnMBR followed by nanofiltration (NF), where powdered activated carbon (PAC) was added to enhance OMPs removal. No significant effects of OMPs spiking and NF connection on bulk organics removal and biogas production were observed. Amitriptyline, diphenhydramine, fluoxetine, sulfamethoxazole, TDCPP and trimethoprim showed readily biodegradable characteristics with consistent biological removal over 80%. Atrazine, carbamazepine, DEET, Dilantin, primidone and TCEP showed refractory characteristics with biological removal below 40%. Acetaminophen, atenolol and caffeine showed a prolonged adaption time of around 45 d, with initial biological removal below 40% and up to 50-80% after this period. Most readily biodegradable OMPs contained a strong electron donating group. Most refractory OMPs contained a strong electron withdrawing group or a halogen substitute. NF showed consistent high rejection of 80-92% with an average of 87% for all OMPs, which resulted in higher OMPs removal in AnMBR-NF than in AnMBR alone, especially for refractory OMPs. Limited sorption performance of PAC for OMPs removal was mainly due to low and batch dosage (100 mg/L) as well as the competitive sorption caused by bulk organics.

  8. Selective separation and concentration of antihypertensive peptides from rapeseed protein hydrolysate by electrodialysis with ultrafiltration membranes.

    Science.gov (United States)

    He, Rong; Girgih, Abraham T; Rozoy, Elodie; Bazinet, Laurent; Ju, Xing-Rong; Aluko, Rotimi E

    2016-04-15

    Rapeseed protein isolate was subjected to alcalase digestion to obtain a protein hydrolysate that was separated into peptide fractions using electrodialysis with ultrafiltration membrane (EDUF) technology. The EDUF process (6h duration) led to isolation of three peptide fractions: anionic (recovered in KCl-1 compartment), cationic (recovered in KCl-2 compartment), and those that remained in the feed compartment, which was labeled final rapeseed protein hydrolysate (FRPH). As expected the KCl-1 peptides were enriched in negatively-charged (43.57%) while KCl-2 contained high contents of positively-charged (28.35%) amino acids. All the samples inhibited angiotensin converting enzyme (ACE) and renin activities in dose-dependent manner with original rapeseed protein hydrolysate having the least ACE-inhibitory IC50 value of 0.0932±0.0037 mg/mL while FRPH and KCl-2 had least renin-inhibitory IC50 values of 0.47±0.05 and 0.55±0.06 mg/mL, respectively. Six hours after oral administration (100 mg/kg body weight) to spontaneously hypertensive rats, the FRPH produced the maximum systolic blood pressure reduction of -51 mmHg. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Removal of emerging contaminants by simultaneous application of membrane ultrafiltration, activated carbon adsorption, and ultrasound irradiation

    International Nuclear Information System (INIS)

    Secondes, Mona Freda N.; Naddeo, Vincenzo; Belgiorno, Vincenzo; Ballesteros, Florencio

    2014-01-01

    Highlights: • Above 99% of the emerging contaminants were removed in the USAMe process. • Influence of PAC dose and US frequency on removal is studied. • Improved performance is due to PAC adsorption enhancement and sonolytic degradation. • US irradiation improved efficiency and delayed declines in the removal of contaminants. • Performance of the hybrid process is better under lower frequency ultrasound irradiation. -- Abstract: Advanced wastewater treatment is necessary to effectively remove emerging contaminants (ECs) with chronic toxicity, endocrine disrupting effects, and the capability to induce the proliferation of highly resistant microbial strains in the environment from before wastewater disposal or reuse. This paper investigates the efficiency of a novel hybrid process that applies membrane ultrafiltration, activated carbon adsorption, and ultrasound irradiation simultaneously to remove ECs. Diclofenac, carbamazepine, and amoxicillin are chosen for this investigation because of their assessed significant environmental risks. Removal mechanisms and enhancement effects are analysed in single and combined processes. The influence of adsorbent dose and ultrasonic frequency to EC removal are also investigated. Results suggest that adsorption is probably the main removal mechanism and is affected by the nature of ECs and the presence of other components in the mixture. Almost complete removals are achieved in the hybrid process for all ECs

  10. Performance of ceramic ultrafiltration and reverse osmosis membranes in treating car wash wastewater for reuse.

    Science.gov (United States)

    Moazzem, Shamima; Wills, Jamie; Fan, Linhua; Roddick, Felicity; Jegatheesan, Veeriah

    2018-03-01

    Reusing treated effluents in industries is a great option to conserve freshwater resources. For example, car wash centres all over Australia are estimated to use 17.5 billion litres of water and discharge it as wastewater and spend $75 million a year for both purchasing fresh water and for treating and/or discharging the wastewater. Therefore, it is important to develop simple but reliable systems that can help to treat and reuse car wash wastewater. Significant savings could also be associated with the implementation of such systems. This study evaluates the performance of granular and membrane filtration systems with coagulation/flocculation and sedimentation in treating car wash wastewater for the purpose of reuse. Overall, 99.9% of turbidity, 100% of suspended solids and 96% of COD were removed from the car wash wastewater after treating by coagulation, flocculation, sedimentation, sand filtration, ceramic ultrafiltration and reverse osmosis and the treated water meets the standards required for class A recycled water in Australia and standards imposed in Belgium and China. The treated water can be reused. However, optimisation is required to reduce the sludge produced by this system.

  11. Removal of emerging contaminants by simultaneous application of membrane ultrafiltration, activated carbon adsorption, and ultrasound irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Secondes, Mona Freda N. [Environmental Engineering Graduate Program, Department of Chemical Engineering, University of the Philippines – Diliman, Quezon City (Philippines); Naddeo, Vincenzo, E-mail: vnaddeo@unisa.it [Sanitary and Environmental Engineering Division (SEED), Department of Civil Engineering, University of Salerno, Fisciano 84084 (Saudi Arabia) (Italy); Belgiorno, Vincenzo [Sanitary and Environmental Engineering Division (SEED), Department of Civil Engineering, University of Salerno, Fisciano 84084 (Saudi Arabia) (Italy); Ballesteros, Florencio [Environmental Engineering Graduate Program, Department of Chemical Engineering, University of the Philippines – Diliman, Quezon City (Philippines)

    2014-01-15

    Highlights: • Above 99% of the emerging contaminants were removed in the USAMe process. • Influence of PAC dose and US frequency on removal is studied. • Improved performance is due to PAC adsorption enhancement and sonolytic degradation. • US irradiation improved efficiency and delayed declines in the removal of contaminants. • Performance of the hybrid process is better under lower frequency ultrasound irradiation. -- Abstract: Advanced wastewater treatment is necessary to effectively remove emerging contaminants (ECs) with chronic toxicity, endocrine disrupting effects, and the capability to induce the proliferation of highly resistant microbial strains in the environment from before wastewater disposal or reuse. This paper investigates the efficiency of a novel hybrid process that applies membrane ultrafiltration, activated carbon adsorption, and ultrasound irradiation simultaneously to remove ECs. Diclofenac, carbamazepine, and amoxicillin are chosen for this investigation because of their assessed significant environmental risks. Removal mechanisms and enhancement effects are analysed in single and combined processes. The influence of adsorbent dose and ultrasonic frequency to EC removal are also investigated. Results suggest that adsorption is probably the main removal mechanism and is affected by the nature of ECs and the presence of other components in the mixture. Almost complete removals are achieved in the hybrid process for all ECs.

  12. Study on treating of low-level radioactive reactor wastewater by combined membrane process (UF-RO)

    International Nuclear Information System (INIS)

    Lu Yunyun; Cao Qiru; Chen Yunming; Huang Lijuan; Bai Xiaofeng; Li Bing; Feng Liang

    2013-01-01

    According to the characteristics of radionuclide exists in the low-level radioactive reactor waste water from HFETR, we use a new combined membrane process separation technology to study the efficient treating of low-lever radioactive reactor wastewater. First, the prepared the simulated wastewater contained Cs + , Sr 2+ , CO 2+ , Ni 2+ , and Fe 3+ . Then, we sequentially investigated the pressure, ion concentration, pH value and EDTA, which have effects on the desalination rate of membrane processing metal ions in wastewater. The results show that: in the condition of pH = 7, and added 0.15 mol/L EDTA, the simulated wastewater separated by UF-RO, desalination rates of Cs + , Sr 2+ , CO 2+ , Ni 2+ and Fe 3+ are all above 95%; In the subsequent trials, adding 0.15 mol/L EDTA into the radioactive residuary solution, and then treating by UF-RO-RO, the decontamination efficiency can reach 95.7%. (authors)

  13. Development of multifunctional nano/ultrafiltration membrane based on a chitosan thin film on alginate electrospun nanofibres

    CSIR Research Space (South Africa)

    Mokhena, Teboho C

    2017-07-01

    Full Text Available of Chemistry, University of the Free State (Qwaqwa Campus), Phuthaditjhaba, South Africa 3 Center for Advanced Materials, Qatar University, Doha, Qatar Abstract The aim of this study was to develop a high flux three-tier composite membrane composed of a... of multifunctional nano/ultrafiltration membrane based on a chitosan thin film on alginate electrospun nanofibres T.C. Mokhena1,2, A.S. Luyt3* 1 CSIR Materials Science and Manufacturing, Polymers and Composites, Port Elizabeth, South Africa. 2 Department...

  14. Effects of Additives on the Morphology and Performance of PPTA/PVDF in Situ Blend UF Membrane

    Directory of Open Access Journals (Sweden)

    Hong-Bin Li

    2014-06-01

    Full Text Available Poly(p-phenylene terephtalamide (PPTA, a high-performance polymer with high modulus and good hydrophilicity, is often used as a reinforced material. However, due to its high crystallity, micro-phase separation often occurs in the blends. In this paper, PPTA/poly(vinylidene fluoride (PVDF compatible blend solution was synthesized by in situ polycondensation. Blend ultra-filtration membrane was prepared through the immersion phase inversion process. In order to obtain desired pore structure, the effects of different additives including hydrophilic polymer (polyethylene glycol (PEG, inorganic salt (lithium chloride (LiCl and the surfactant (Tween-80 on the morphology and performance of PPTA/PVDF blend membranes were studied. The membrane formation process was investigated through ternary phase diagram (thermodynamics and viscosities (kinetics analysis. It was found that, with the increasing of LiCl content, a porous membrane structure with long finger-like pores was formed due to the accelerated demixing process which resulted in the increase of porosity and pore diameter as well as the enhancement of water flux and the decline of PEG rejection. When Tween content increased to over 3 wt%, dynamic viscosity became the main factor resulting in a decreased phase separation rate. The transfer of PEG and LiCl molecules onto membrane surface increased the surface hydrophilicity. The effect of Tween content on membrane hydrophilicity was also correlated with the compatibility of blend components.

  15. Behavior of pharmaceuticals and drugs of abuse in a drinking water treatment plant (DWTP) using combined conventional and ultrafiltration and reverse osmosis (UF/RO) treatments

    Energy Technology Data Exchange (ETDEWEB)

    Boleda, Ma Rosa [AGBAR-Aiguees de Barcelona, Gral Batet 5-7, 08028 Barcelona (Spain); Galceran, Ma Teresa [University of Barcelona, Department Analytical Chemistry, Av. Diagonal 647, 08028 Barcelona (Spain); Ventura, Francesc, E-mail: fventura@agbar.es [AGBAR-Aiguees de Barcelona, Gral Batet 5-7, 08028 Barcelona (Spain)

    2011-06-15

    The behavior along the potabilization process of 29 pharmaceuticals and 12 drugs of abuse identified from a total of 81 compounds at the intake of a drinking water treatment plant (DWTP) has been studied. The DWTP has a common treatment consisting of dioxychlorination, coagulation/flocculation and sand filtration and then water is splitted in two parallel treatment lines: conventional (ozonation and carbon filtration) and advanced (ultrafiltration and reverse osmosis) to be further blended, chlorinated and distributed. Full removals were reached for most of the compounds. Iopromide (up to 17.2 ng/L), nicotine (13.7 ng/L), benzoylecgonine (1.9 ng/L), cotinine (3.6 ng/L), acetaminophen (15.6 ng/L), erythromycin (2.0 ng/L) and caffeine (6.0 ng/L) with elimination efficiencies {>=}94%, were the sole compounds found in the treated water. The advanced treatment process showed a slightly better efficiency than the conventional treatment to eliminate pharmaceuticals and drugs of abuse. - Highlights: > The presence of pharmaceuticals and drugs of abuse in surface water was demonstrated. > Elimination in both potabilization processes reached levels >99% for most compounds. > Four pharmaceuticals and three drugs of abuse survived the potabilization process. - The efficiency of potabilization processes to eliminate or transform pharmaceuticals and illicit drugs is evaluated.

  16. Behavior of pharmaceuticals and drugs of abuse in a drinking water treatment plant (DWTP) using combined conventional and ultrafiltration and reverse osmosis (UF/RO) treatments

    International Nuclear Information System (INIS)

    Boleda, Ma Rosa; Galceran, Ma Teresa; Ventura, Francesc

    2011-01-01

    The behavior along the potabilization process of 29 pharmaceuticals and 12 drugs of abuse identified from a total of 81 compounds at the intake of a drinking water treatment plant (DWTP) has been studied. The DWTP has a common treatment consisting of dioxychlorination, coagulation/flocculation and sand filtration and then water is splitted in two parallel treatment lines: conventional (ozonation and carbon filtration) and advanced (ultrafiltration and reverse osmosis) to be further blended, chlorinated and distributed. Full removals were reached for most of the compounds. Iopromide (up to 17.2 ng/L), nicotine (13.7 ng/L), benzoylecgonine (1.9 ng/L), cotinine (3.6 ng/L), acetaminophen (15.6 ng/L), erythromycin (2.0 ng/L) and caffeine (6.0 ng/L) with elimination efficiencies ≥94%, were the sole compounds found in the treated water. The advanced treatment process showed a slightly better efficiency than the conventional treatment to eliminate pharmaceuticals and drugs of abuse. - Highlights: → The presence of pharmaceuticals and drugs of abuse in surface water was demonstrated. → Elimination in both potabilization processes reached levels >99% for most compounds. → Four pharmaceuticals and three drugs of abuse survived the potabilization process. - The efficiency of potabilization processes to eliminate or transform pharmaceuticals and illicit drugs is evaluated.

  17. Behavior of pharmaceuticals and drugs of abuse in a drinking water treatment plant (DWTP) using combined conventional and ultrafiltration and reverse osmosis (UF/RO) treatments.

    Science.gov (United States)

    Boleda, M A Rosa; Galceran, M A Teresa; Ventura, Francesc

    2011-06-01

    The behavior along the potabilization process of 29 pharmaceuticals and 12 drugs of abuse identified from a total of 81 compounds at the intake of a drinking water treatment plant (DWTP) has been studied. The DWTP has a common treatment consisting of dioxychlorination, coagulation/flocculation and sand filtration and then water is splitted in two parallel treatment lines: conventional (ozonation and carbon filtration) and advanced (ultrafiltration and reverse osmosis) to be further blended, chlorinated and distributed. Full removals were reached for most of the compounds. Iopromide (up to 17.2 ng/L), nicotine (13.7 ng/L), benzoylecgonine (1.9 ng/L), cotinine (3.6 ng/L), acetaminophen (15.6 ng/L), erythromycin (2.0 ng/L) and caffeine (6.0 ng/L) with elimination efficiencies ≥ 94%, were the sole compounds found in the treated water. The advanced treatment process showed a slightly better efficiency than the conventional treatment to eliminate pharmaceuticals and drugs of abuse. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Development of high performance nano-porous polyethersulfone ultrafiltration membranes with hydrophilic surface and superior antifouling properties

    International Nuclear Information System (INIS)

    Rahimpour, Ahmad; Madaeni, Sayed Siavash; Jahanshahi, Mohsen; Mansourpanah, Yaghoub; Mortazavian, Narmin

    2009-01-01

    Hydrophilic nano-porous polyethersulfone ultrafiltration membranes were developed for milk concentration. The membranes were prepared from new dope solution containing polyethersulfone (PES)/polyvinylpirrolidone (PVP)/polyethyleneglycole (PEG)/cellulose acetate phthalate (CAP)/acrylic acid/Triton X-100 using phase inversion induced by immersion precipitation technique. This casting solution leads to formation of new hydrophilic membranes. The morphological studies were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). In addition, the hydrophilicity and performance of membranes were examined by contact angel measurements and cross-flow filtration (pure water flux, milk water permeation, protein rejection and antifouling measurements). The contact angle measurements indicate that a surface with superior hydrophilicity was obtained for PES membranes. Two concentrations of PES (16 and 14.4 wt.%) and two different non-solvents (pure water and mixtures of water and IPA) were used for preparation of membranes. The morphological studies showed that the higher concentration of PES and the presence of IPA in the gelation media results in formation of a membrane with a dense top and sub-layer with small pores on the surface. The pure water flux of membranes was decreased when higher polymer concentration and mixtures of water and IPA were employed for membrane formation. On the other hand, the milk water permeation and protein rejection were increased using mixtures of water and IPA as non-solvent. Furthermore, the fouling analysis of the membranes demonstrated that the membrane surface with fewer tendencies for fouling was obtained.

  19. High Concentration Protein Ultrafiltration: a Comparative Fouling Assessment

    Science.gov (United States)

    Lim, Y. P.; Mohammad, A. W.

    2018-05-01

    In this paper, the predominant fouling mechanism via pH manipulation in gelatin ultrafiltration (UF) at constant operating pressure was studied. Two 30 kDa molecular weight cut off (MWCO) UF membranes with different hydrophilic/hydrophobic properties were tested at solution pH near gelatin isoelectric point (IEP), pH below and above gelatin’s IEP. The resistance-in-series model was used to determine quantitatively the contribution of each filtration resistance occurred during gelatin UF. The governing fouling mechanisms were investigated using classical blocking laws. The results demonstrated that concentration polarization remain as dominant fouling resistance in gelatin UF, but exceptional case was observed at pH away from gelatin’s IEP, showing that combined reversible and irreversible fouling resistances contributed around 57% and 37%, respectively to the overall fouling resistances. Under all experimental condition tested, permeate flux decline was accurately predicted by all the models studied. Fouling profile was fitted well with “Standard Blocking”, “Intermediate Blocking” and “Cake Filtration” model for regenerated cellulose acetate (RCA) membrane and “Cake Filtration” model for polyethersulphone (PES) membrane.

  20. Cellulase retention and sugar removal by membrane ultrafiltration during lignocellulosic biomass hydrolysis.

    Science.gov (United States)

    Knutsen, Jeffrey S; Davis, Robert H

    2004-01-01

    Technologies suitable for the separation and reuse of cellulase enzymes during the enzymatic saccharification of pretreated corn stover are investigated to examine the economic and technical viability of processes that promote cellulase reuse while removing inhibitory reaction products such as glucose and cellobiose. The simplest and most suitable separation is a filter with relatively large pores on the order of 20-25 mm that retains residual corn stover solids while passing reaction products such as glucose and cellobiose to form a sugar stream for a variety of end uses. Such a simple separation is effective because cellulase remains bound to the residual solids. Ultrafiltration using 50-kDa polyethersulfone membranes to recover cellulase enzymes in solution was shown not to enhance further the saccharification rate or overall conversion. Instead, it appears that the necessary cellulase enzymes, including beta-glucosidase, are tightly bound to the substrate; when fresh corn stover is contacted with highly washed residual solids, without the addition of fresh enzymes, glucose is generated at a high rate. When filtration was applied multiple times, the concentration of inhibitory reaction products such as glucose and cellobiose was reduced from 70 to 10 g/L. However, an enhanced saccharification performance was not observed, most likely because the concentration of the inhibitory products remained too high. Further reduction in the product concentration was not investigated, because it would make the reaction unnecessarily complex and result in a product stream that is much too dilute to be useful. Finally, an economic analysis shows that reuse of cellulase can reduce glucose production costs, especially when the enzyme price is high. The most economic performance is shown to occur when the cellulase enzyme is reused and a small amount of fresh enzyme is added after each separation step to replace lost or deactivated enzyme.

  1. Development of a High Performance PES Ultrafiltration Hollow Fiber Membrane for Oily Wastewater Treatment Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Noor Adila Aluwi Shakir

    2015-12-01

    Full Text Available This study attempts to optimize the spinning process used for fabricating hollow fiber membranes using the response surface methodology (RSM. The spinning factors considered for the experimental design are the dope extrusion rate (DER, air gap length (AGL, coagulation bath temperature (CBT, bore fluid ratio (BFR, and post-treatment time (PT whilst the response investigated is rejection. The optimal spinning conditions promising the high rejection performance of polyethersulfone (PES ultrafiltration hollow fiber membranes for oily wastewater treatment are at the dope extrusion rate of 2.13 cm3/min, air gap length of 0 cm, coagulation bath temperature of 30 °C, and bore fluid ratio (NMP/H2O of 0.01/99.99 wt %. This study will ultimately enable the membrane fabricators to produce high-performance membranes that contribute towards the availability of a more sustainable water supply system.

  2. Unbound fraction of fluconazole and linezolid in human plasma as determined by ultrafiltration: Impact of membrane type.

    Science.gov (United States)

    Kratzer, Alexander; Kees, Frieder; Dorn, Christoph

    2016-12-15

    Ultrafiltration is a rapid and convenient method to determine the free concentrations of drugs in plasma. Several ultrafiltration devices based on Eppendorf cups are commercially available, but are not validated for such use by the manufacturer. Plasma pH, temperature and relative centrifugal force as well as membrane type can influence the results. In the present work, we developed an ultrafiltration method in order to determine the free concentrations of linezolid or fluconazole, both neutral and moderately lipophilic antiinfective drugs for parenteral as well as oral administration, in plasma of patients. Whereas both substances behaved relatively insensitive in human plasma regarding variations in pH (7.0-8.5), temperature (5-37°C) or relative centrifugal force (1000-10.000xg), losses of linezolid were observed with the Nanosep Omega device due to adsorption onto the polyethersulfone membrane (unbound fraction 75% at 100mg/L and 45% at 0.1mg/L, respectively). No losses were observed with Vivacon which is equipped with a membrane of regenerated cellulose. With fluconazole no differences between Nanosep and Vivacon were observed. Applying standard conditions (pH 7.4/37°C/1000xg/20min), the mean unbound fraction of linezolid in pooled plasma from healthy volunteers was 81.5±2.8% using Vivacon, that of fluconazole was 87.9±3.5% using Nanosep or 89.4±3.3% using Vivacon. The unbound fraction of linezolid was 85.4±3.7% in plasma samples from surgical patients and 92.1±6.2% in ICU patients, respectively. The unbound fraction of fluconazole was 93.9±3.3% in plasma samples from ICU patients. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Organic fouling behavior of superhydrophilic polyvinylidene fluoride (PVDF) ultrafiltration membranes functionalized with surface-tailored nanoparticles: Implications for organic fouling in membrane bioreactors

    KAUST Repository

    Liang, Shuai

    2014-08-01

    This study systematically investigates the organic fouling behavior of a superhydrophilic polyvinylidene fluoride (PVDF) ultrafiltration membrane functionalized via post-fabrication tethering of surface-tailored silica nanoparticles to poly(methacrylic acid)-grafted PVDF membrane surface. Sodium alginate (SA), Suwannee River natural organic matter (SRNOM), and bovine serum albumin (BSA) were used as model organic foulants to investigate the antifouling behavior of the superhydrophilic membrane with combined-fouling (mixture of foulants) and individual-fouling (single foulant) tests. A membrane bioreactor (MBR) plant supernatant was also used to verify the organic antifouling property of the superhydrophilic membrane under realistic conditions. Foulant size distributions and foulant-membrane interfacial forces were measured to interpret the observed membrane fouling behavior. Molecular weight cutoff measurements confirmed that membrane functionalization did not adversely affect the intrinsic membrane selectivity. Both filtration tests with the synthetic foulant-mixture solution (containing SA, SRNOM, and BSA) and MBR plant supernatant demonstrated the reliability and durability of the antifouling property of the superhydrophilic membrane. The conspicuous reduction in foulant-membrane interfacial forces for the functionalized membrane further verified the antifouling properties of the superhydrophilic membrane, suggesting great potential for applications in wastewater treatment. © 2014 Elsevier B.V.

  4. Preparation of Cu{sub 2}O nanowire-blended polysulfone ultrafiltration membrane with improved stability and antimicrobial activity

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zehai; Ye, Shuaiju; Fan, Zheng; Ren, Fanghua; Gao, Congjie [Zhejiang University of Technology, Institute of Oceanic and Environmental Chemical Engineering, College of Chemical Engineering and Material Science and College of Ocean, and State Key Lab Breeding Base of Green Chemical Synthesis Technology and Zhejiang Collaborative Innovation Center of Membrane Separation and Water Treatment (China); Li, Qingbiao; Li, Guoqing [Quanzhou Normal University, College of Chemistry and Life Science (China); Zhang, Guoliang, E-mail: membrane86571@163.com, E-mail: guoliangz@zjut.edu.cn [Zhejiang University of Technology, Institute of Oceanic and Environmental Chemical Engineering, College of Chemical Engineering and Material Science and College of Ocean, and State Key Lab Breeding Base of Green Chemical Synthesis Technology and Zhejiang Collaborative Innovation Center of Membrane Separation and Water Treatment (China)

    2015-10-15

    Polysulfone (PSF) membranes have been widely applied in water and wastewater treatment, food-processing and biomedical fields. In this study, we report the preparation of modified PSF membranes by blending PSF with Cu{sub 2}O nanowires (NWs) to improve their stability and antifouling activity. Synthesis of novel Cu{sub 2}O NWs/PSF-blended ultrafiltration membrane was achieved via phase inversion method by dispersing one-dimensional Cu{sub 2}O nanowires in PSF casting solutions. Various techniques such as XRD, SEM, TEM, and EDS were applied to characterize and investigate the properties of nanowires and membranes. The introduced Cu{sub 2}O nanowires can firmly be restricted into micropores of PSF membranes, and therefore, they can effectively prevent the serious leaking problem of inorganic substances in separation process. The blended PSF membranes also provided enhanced antimicrobial activity and superior permeation property compared to pure PSF membrane. The overall work can not only provide a new way for preparation of novel blended membranes with multidimensional nanomaterials, but can also be beneficial to solve the annoying problem of biofouling.

  5. Recovery of biomolecules from marinated herring (Clupea harengus) brine using ultrafiltration through ceramic membranes

    DEFF Research Database (Denmark)

    Gringer, Nina; Hosseini, Seyed Vali; Svendsen, Tore

    2015-01-01

    Marinated herring processing brines, which are usually discarded, are rich in salt, protein, non-protein nitrogen, iron, fatty acids, antioxidant and even possess enzymatic activity. This study investigated the performance of ceramic ultrafiltration of two herring spice brines with a major focus...

  6. MF/UF rejection and fouling potential of algal organic matter from bloom-forming marine and freshwater algae

    KAUST Repository

    Villacorte, Loreen O.

    2015-07-01

    Pretreatment with microfiltration (MF) or ultrafiltration (UF) membranes has been proposed for seawater reverse osmosis (SWRO) plants to address operational issues associated with algal blooms. Here, we investigated the MF/UF rejection and fouling potential of algal organic matter (AOM) released by common species of bloom-forming marine (Alexandrium tamarense and Chaetoceros affinis) and freshwater (Microcystis sp.) algae. Batch culture monitoring of the three algal species illustrated varying growth pattern, cell concentration, AOM released and membrane fouling potential. The high membrane fouling potential of the cultures can be directly associated (R2>0.85) with AOM such as transparent exopolymer particle (TEP) while no apparent relationship with algal cell concentration was observed. The AOM comprised mainly biopolymers (e.g., polysaccharides and proteins) and low molecular weight organic compounds (e.g., humic-like substances). The former were largely rejected by MF/UF membranes while the latter were poorly rejected. MF (0.4μm and 0.1μm pore size) rejected 14%-56% of biopolymers while conventional UF (100kDa) and tight UF (10kDa) rejected up to 83% and 97%, respectively. The retention of AOM resulted in a rapid increase in trans-membrane pressure (δP) over time, characterised by pore blocking followed by cake filtration with enhanced compression as illustrated by an exponential progression of δP. © 2015 Elsevier B.V.

  7. Prediction of power consumption and performance in ultrafiltration of simulated latex effluent using non-uniform pore sized membranes

    Energy Technology Data Exchange (ETDEWEB)

    Abdelrasoul, Amira; Doan, Huu; Lohi, Ali; Cheng, Chil-Hung [Ryerson University, 350 Victoria Street, Toronto (Canada)

    2016-03-15

    Tha aim of the present study was to develop a series of numerical models for an accurate prediction of the power consumption in ultrafiltration of simulated latex effluent. The developed power consumption model incorporated fouling attachment, as well as chemical and physical factors in membrane fouling, in order to ensure accurate prediction and scale-up. This model was applied to heterogeneous membranes with non-uniform pore sizes at a given operating conditions and membrane surface charges. Polysulfone flat membrane, with a membrane molecular weight cutoff (MWCO) of 60,000 dalton, at different surface charges was used under a constant flow rate and cross-flow mode. In addition, the developed models were examined using various membranes at a variety of surface charges so as to test the overall reliability and accuracy of these models. The power consumption predicted by the models corresponded to the calculated values from the experimental data for various hydrophilic and hydrophobic membranes with an error margin of 6.0% up to 19.1%.

  8. Evaluation of Membrane Ultrafiltration and Residual Chlorination as a Decentralized Water Treatment Strategy for Ten Rural Healthcare Facilities in Rwanda

    Directory of Open Access Journals (Sweden)

    Alexandra Huttinger

    2015-10-01

    Full Text Available There is a critical need for safe water in healthcare facilities (HCF in low-income countries. HCF rely on water supplies that may require additional on-site treatment, and need sustainable technologies that can deliver sufficient quantities of water. Water treatment systems (WTS that utilize ultrafiltration membranes for water treatment can be a useful technology in low-income countries, but studies have not systematically examined the feasibility of this technology in low-income settings. We monitored 22 months of operation of 10 WTS, including pre-filtration, membrane ultrafiltration, and chlorine residual disinfection that were donated to and operated by rural HCF in Rwanda. The systems were fully operational for 74% of the observation period. The most frequent reasons for interruption were water shortage (8% and failure of the chlorination mechanism (7%. When systems were operational, 98% of water samples collected from the HCF taps met World Health Organization (WHO guidelines for microbiological water quality. Water quality deteriorated during treatment interruptions and when water was stored in containers. Sustained performance of the systems depended primarily on organizational factors: the ability of the HCF technician to perform routine servicing and repairs, and environmental factors: water and power availability and procurement of materials, including chlorine and replacement parts in Rwanda.

  9. An integrated membrane system for the biocatalytic production of 3′-sialyllactose from dairy by-products

    DEFF Research Database (Denmark)

    Luo, Jianquan; Nordvang, Rune Thorbjørn; Morthensen, Sofie Thage

    2014-01-01

    An integrated membrane system was investigated for the production of 30-sialyllactose by an engineered sialidase using casein glycomacropeptide (CGMP) and lactose as substrates. CGMP was purified by ultrafiltration (UF) to remove any small molecules present and then an enzymatic membrane reactor ...

  10. Renewable energy powered membrane technology. 2. The effect of energy fluctuations on performance of a photovoltaic hybrid membrane system

    OpenAIRE

    Richards, B.S.; Capão, D.P.S.; Schäfer, Andrea

    2008-01-01

    This paper reports on the performance fluctuations during the operation of a batteryless hybrid ultrafiltration-nanofiltration/reverse osmosis (UF-NF/RO) membrane desalination system powered by photovoltaics treating brackish groundwater in outback Australia. The renewable energy powered membrane (RE-membrane) system is designed to supply clean drinking water to a remote community of about 50 inhabitants. The performance of the RE-membrane system over four different solar days is summarized u...

  11. Development of High-Antifouling PPSU Ultrafiltration Membrane by Using Compound Additives: Preparation, Morphologies, and Filtration Resistant Properties.

    Science.gov (United States)

    Liu, Jie; Zhong, Zhencheng; Ma, Rui; Zhang, Weichen; Li, Jiding

    2016-06-21

    In this study, flat sheet asymmetric polyphenylsulfone (PPSU) ultrafiltration membranes with enhanced antifouling properties were prepared with a non-solvent induced phase separation (NIPS) method through compound additives containing a polymeric pore-forming agent, a small molecular non-solvent and a surfactant. The formation processes of the porous asymmetric membranes with different kinds of additives were studied in detail, and the microstructure controllable preparation of membrane was achieved by establishing a bridge between the membrane preparation parameters and separation performances. All prepared membranes were characterized by using a scanning electron microscope (SEM), contact angle analysis, porosity, maximum pore size, water and BSA solution permeability studies. The performance efficiency of the membrane was evaluated by using BSA as a model foulant in terms of permeability, solute rejection (R), Rm (membrane inherent resistance), Rc (cake layer resistance), and Rp (pore plugging resistance). The results showed that when the compound additives were used, the inter-connected pores were observed, maximum pore size, contact angle and membrane filtration resistance decreased, while the porosity increased. When PVP compound additives were added, the water flux increased from 80.4 to 148.1 L/(m²·h), the BSA rejection increased from 53.2% to 81.5%. A similar trend was observed for membranes with added PEG compound additives; the water flux and BSA rejection simultaneously increased. The filtration resistance decreased as a result of compound additives. The uniformity of membrane and the number of effective pores could be enhanced by adding compound additives through the cooperation of different additives.

  12. Development of High-Antifouling PPSU Ultrafiltration Membrane by Using Compound Additives: Preparation, Morphologies, and Filtration Resistant Properties

    Directory of Open Access Journals (Sweden)

    Jie Liu

    2016-06-01

    Full Text Available In this study, flat sheet asymmetric polyphenylsulfone (PPSU ultrafiltration membranes with enhanced antifouling properties were prepared with a non-solvent induced phase separation (NIPS method through compound additives containing a polymeric pore-forming agent, a small molecular non-solvent and a surfactant. The formation processes of the porous asymmetric membranes with different kinds of additives were studied in detail, and the microstructure controllable preparation of membrane was achieved by establishing a bridge between the membrane preparation parameters and separation performances. All prepared membranes were characterized by using a scanning electron microscope (SEM, contact angle analysis, porosity, maximum pore size, water and BSA solution permeability studies. The performance efficiency of the membrane was evaluated by using BSA as a model foulant in terms of permeability, solute rejection (R, Rm (membrane inherent resistance, Rc (cake layer resistance, and Rp (pore plugging resistance. The results showed that when the compound additives were used, the inter-connected pores were observed, maximum pore size, contact angle and membrane filtration resistance decreased, while the porosity increased. When PVP compound additives were added, the water flux increased from 80.4 to 148.1 L/(m2·h, the BSA rejection increased from 53.2% to 81.5%. A similar trend was observed for membranes with added PEG compound additives; the water flux and BSA rejection simultaneously increased. The filtration resistance decreased as a result of compound additives. The uniformity of membrane and the number of effective pores could be enhanced by adding compound additives through the cooperation of different additives.

  13. Effect of PAC addition on immersed ultrafiltration for the treatment of algal-rich water

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Yan, E-mail: zhang.yan113@163.com [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090 (China); Tian Jiayu; Nan Jun; Gao Shanshan; Liang Heng; Wang Meilian; Li Guibai [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090 (China)

    2011-02-28

    The aim of this study was to evaluate the effect of powdered activated carbon (PAC) addition on the treatment of algal-rich water by immersed ultrafiltration (UF), in terms of permeate quality and membrane fouling. Experiments were performed with a hollow-fiber polyvinyl chloride ultrafiltration membrane at a laboratory scale, 20-25 deg, C and 10 L/(m{sup 2} h) constant permeate flux. UF could achieve an absolute removal of Microcystis aeruginosa cells, but a poor removal of algogenic organic matter (AOM) released into water, contaminants responsible for severe membrane fouling. The addition of 4 g/L PAC to the immersed UF reactor significantly alleviated the development of trans-membrane pressure and enhanced the removal of dissovled organic carbon (by 10.9 {+-} 1.7%), UV{sub 254} (by 27.1 {+-} 1.7%), and microcystins (expressed as MC-LR{sub eq}, by 40.8 {+-} 4.2%). However, PAC had little effect on the rejection of hydrophilic high molecular weight AOM such as carbohydrates and proteins. It was also identified that PAC reduced the concentrations of carbohydrates and proteins in the reactor due to decreased light intensity, as well as the MC-LR{sub eq} concentration by PAC adsorption.

  14. Hollow fiber membrane ultrafiltration of a simulated secondary treatment wastewater. Process and fouling modeling

    OpenAIRE

    Soler Cabezas, José Luis; Vincent Vela, Maria Cinta; Mendoza Roca, José Antonio; Martínez Francisco, Francisco Juan

    2012-01-01

    It is well known that there is a scarcity of drinking and irrigation water around the world nowadays. According to the United Nations, water scarcity affects 1.2 billion people (one-fifth of the world's population) and the water use has been growing at twice the rate of population increase in the last century. This fact makes the reuse of the wastewater from municipal wastewater treatment plants (MWTPs) an interesting option. Ultrafiltration after the secondary settling is becoming more f...

  15. Electro-ultrafiltration of industrial enzyme solutions

    DEFF Research Database (Denmark)

    Enevoldsen, Ann Dorrit; Hansen, Erik Børresen; Jonsson, Gunnar Eigil

    2007-01-01

    To reduce the problems with fouling and concentration polarization during crossflow ultrafiltration of industrial enzyme solutions an electric field is applied across the membrane. The filtration performance during electro-ultrafiltration (EUF) has been tested with several enzymes. Results show...

  16. Simultaneous determination of free calcium, magnesium, sodium and potassium ion concentrations in simulated milk ultrafiltrate and reconstituted skim milk using the Donnan Membrane Technique

    NARCIS (Netherlands)

    Gao, R.; Temminghoff, E.J.M.; Leeuwen, van H.P.; Valenberg, van H.J.F.; Eisner, M.D.; Boekel, van M.A.J.S.

    2009-01-01

    This study focused on determination of free Ca2+, Mg2+, Na+ and K+ concentrations in a series of CaCl2 solutions, simulated milk ultrafiltrate and reconstituted skim milk using a recently developed Donnan Membrane Technique (DMT). A calcium ion selective electrode was used to compare the DMT

  17. Evaluating the efficiency of different microfiltration and ultrafiltration membranes used as pretreatment for Red Sea water reverse osmosis desalination

    KAUST Repository

    Almashharawi, Samir

    2013-01-01

    Conventional processes are widely used as pretreatment for reverse osmosis (RO) desalination technology since its development. However, these processes require a large footprint and have some limitation issues such as difficulty to maintain a consistent silt density index, coagulation control at low total suspended solids, and management of higher waste sludge. Recently, there has been a rapid growth in the use of low-pressure membranes as pretreatment for RO systems replacing the conventional processes. However, despite the numerous advantages of using this integrated membrane system mainly providing good and stable water quality to RO membranes, many issues have to be addressed. The primary limitation is membrane fouling which reduces the permeate flux; therefore, higher pumping intensity is required to maintain a consistent volume of product. This paper aims to optimize the permeation flux and cleaning frequency by providing high permeate quality. Different low-pressure polyethersulfone membranes with different pore sizes ranging from 0.1 lm to 50 kDa were tested. Eight different filtration configurations have been applied including the variation of coagulant doses aiming to control membrane fouling. Results showed that all the configurations with/without coagulation, provided permeate with excellent water quality which improves the stability of RO performance. However, more stable fluxes with less-energy consumption were achieved by using the 0.1 lm and 100 kDa membranes with 1 mg/L FeCl3 coagulation. The use of UF membranes, having tight pores, without coagulation also proved to be an excellent option for Red Sea water RO pretreatment. © 2013 Desalination Publications.

  18. Whey protein concentration by ultrafiltration and study of functional properties

    Directory of Open Access Journals (Sweden)

    Sidiane Iltchenco

    2018-06-01

    Full Text Available ABSTRACT: This paper aim to evaluate the ultrafiltration (UF process for constituents recovery from whey. Sequences of factorial designs were performed by varying temperature (5 to 40°C and pressure (1 to 3 bar, to maximize the proteins concentration using membrane of 100kDa in dead end system. Based on the best result new experiments were performed with membrane of 50kDa and 10kDa. With the membrane of 50 the protein retention was about 3 times higher than the membrane of 100kDa. The concentrated obtained by UF membrane of 10kDa, 10°C and 2 bar in laboratory scale showed a mean protein retention of 80 %, greater protein solubility, emulsion stability and the identification of β-lactoglobulins (18.3 kDa and α-lactalbumin fractions (14.2kDa. Therefore, the use of membrane of 100 and 50kDa are became a industrially recommendable alternatives to concentration of whey proteins, and/or as a previous step to the fractionation of whey constituents using membrane ≤10kDa, aiming at future applications in different areas (food, pharmaceutical, chemical, etc..

  19. Statistical analysis of data from accelerated ageing tests of PES UF membranes

    NARCIS (Netherlands)

    Zondervan, Edwin; Zwijnenburg, Arie; Roffel, Brian

    2007-01-01

    In this research, membrane life-time was evaluated by means of accelerated ageing experiments. A pressure pulse unit was used to perform the ageing experiments in an accelerated way. An experimental design has been set up and four ageing factors were varied at two levels. The four ageing factors

  20. Investigation of severe UF membrane fouling induced by three marine algal species

    KAUST Repository

    Merle, Tony; Dramas, Laure; Gutierrez, Leonardo; Garcia-Molina, Veronica; Croue, Jean-Philippe

    2016-01-01

    Index (HIFI) was correlated to their biopolymer content but this correlation is specific for each species. Solution pre-filtration through a 1.2 μm membrane proved that cells and particulate algal organic matter (p-AOM) considerably contribute to fouling

  1. Membrane treatment of alkaline bleaching effluents from elementary chlorine free kraft softwood cellulose production.

    Science.gov (United States)

    Oñate, Elizabeth; Rodríguez, Edgard; Bórquez, Rodrigo; Zaror, Claudio

    2015-01-01

    This paper reports experimental results on the sequential use of ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) to fractionate alkaline extraction bleaching effluents from kraft cellulose production. The aim was to unveil the way key pollutants are distributed when subjected to sequential UF/NF/RO membrane separation processes. Alkaline bleaching effluents were obtained from a local pinewood-based mill, featuring elementary chlorine free bleaching to produce high-brightness cellulose. The experimental system was based on a laboratory-scale membrane system, DSS LabStak® M20 Alfa Laval, using Alfa Laval UF and NF/RO membranes, operated at a constant transmembrane pressure (6 bar for UF membranes and 32 bar for NF/RO membranes), at 25°C. Results show that 78% chemical oxygen demand (COD) and total phenols, 82% adsorbable organic halogens (AOX) and 98% colour were retained by UF membranes which have molecular weight cut-off (MWCO) above 10 kDa. In all, 16% of original COD, total phenols and AOX, and the remaining 2% colour were retained by UF membranes within the 1 to 10 kDa MWCO range. Chloride ions were significantly present in all UF permeates, and RO was required to obtain a high-quality permeate with a view to water reuse. It is concluded that UF/NF/RO membranes offer a feasible option for water and chemicals recovery from alkaline bleaching effluents in kraft pulp production.

  2. Preparation and Characterization of Novel Polyvinylidene Fluoride/2-Aminobenzothiazole Modified Ultrafiltration Membrane for the Removal of Cr(VI in Wastewater

    Directory of Open Access Journals (Sweden)

    Xiuju Wang

    2017-12-01

    Full Text Available Hexavalent chromium is one of the main heavy metal pollutants. As the environmental legislation becomes increasingly strict, seeking new technology to treat wastewater containing hexavalent chromium is becoming more and more important. In this research, a novel modified ultrafiltration membrane that could be applied to adsorb and purify water containing hexavalent chromium, was prepared by polyvinylidene fluoride (PVDF blending with 2-aminobenzothiazole via phase inversion. The membrane performance was characterized by evaluation of the instrument of membrane performance, infrared spectroscopy (FTIR, scanning electron microscope (SEM, and water contact angle measurements. The results showed that the pure water flux of the PVDF/2-aminobenzothiazole modified ultrafiltration membrane was 231.27 L/m2·h, the contact angle was 76.1°, and the adsorption capacity of chromium ion was 157.75 µg/cm2. The PVDF/2-aminobenzothiazole modified ultrafiltration membrane presented better adsorption abilities for chromium ion than that of the traditional PVDF membrane.

  3. Effects of Preparation Conditions on Morphology of Polyacrylonitrile Micro/Ultrafiltration Membrane and Its Application in Protein and Fat Separation from Milk

    Directory of Open Access Journals (Sweden)

    Seyed Ali Alavi

    2014-04-01

    Full Text Available Polyacrylonitrile (PAN micro/ultrafiltration membranes were prepared by phase inversion method. The effects of various preparation conditions including polymeric solution concentration, evaporation time, temperature, composition and residence time of the coagulation bath were investigated. Various important membrane characteristics such as pore size, bulk porosity, and mechanical and morphological properties were taken into the consideration. The characterizations were performed by measuring the bubble point, water flux, tensile strength and scanning electron microscopy (SEM analyses. The results showed that by increasing the polymeric solution concentration from 13 to 17 wt%, the porosity and water flux were decreased. Moreover, the membrane skin layer was considerably thickened with a very significant decrease in its pore sizes which was achieved in ultrafiltration region. By increasing the evaporation time at atmospheric pressure, membrane skin layer was thickened and the pore sizes were decreased. Low coagulation bath temperatures (below 30°C resulted in lower pore size, water flux, and an increase in membrane mechanical strength. Introduction of isopropanol (IPA into the water coagulation bath led to lower coagulation rate and consequently, the formation of smaller pores became possible by using pure isopropanol as coagulation bath. Furthermore, by increasing the residence time in coagulation bath, a more porous structure with more uniform pore sizes were formed that showed better mechanical properties. Finally, the so-called ultrafiltration membranes were applied in concentration process of protein and milk fat. A protein rejection more than 93% was attained while a complete removal of milk fat was achieved.

  4. EDTA fouling in dead-end ultrafiltration of low level radioactive wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Lixia [Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC), Graduate School at Shenzhen, Tsinghua University, Shenzhen, 518055 (China); Zhang, Xue [Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Zhao, Xuan, E-mail: zhxinet@mail.tsinghua.edu.cn [Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Hu, Hongying [Environmental Simulation and Pollution Control State Key Joint Laboratory, School of Environment, Tsinghua University, Beijing 100084 (China); State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC), Graduate School at Shenzhen, Tsinghua University, Shenzhen, 518055 (China)

    2015-12-15

    Highlights: • EDTA in LLRW caused unrecoverable UF membrane fouling. • The rejection of nuclides by UF was significantly enhanced with EDTA addition. • The nuclide (except Ag) deposition on membrane increased with EDTA addition. • Reducing EDTA in the feed water or alkaline/ultrasonic washing were suggested. - Abstract: EDTA is widely used as a detergent, and finally enters into wastewater. The influence of EDTA on ultrafiltration of low level radioactive wastewater (LLRW) was investigated under different operation conditions. As the main organic pollutant, EDTA led to unrecoverable membrane fouling and the normalized flux decreased from 100% to 85% depending on its concentration. The clogging caused by EDTA increased the surface roughness of the membrane, leading to the flux reduction. Both nuclide rejections and depositions on the membrane surfaces were enhanced with EDTA addition, due to the strong complexation of the nuclides with EDTA. However, Ag deposition on the membrane decreased slightly in the presence of EDTA, which may be caused by the stronger attraction of Ag to the unmodified membrane than that to the EDTA-modified one. Transmembrane pressure (TMP) and molecular weight cut off (MWCO) of membranes had negligible effects on membrane fouling, while the nuclide rejections by membrane and the depositions of nuclides on membrane both decreased significantly when the TMP increased to 0.2 MPa and MWCO increased from 5 kDa to 30 kDa. Based on these results, it clearly showed that EDTA even at a low concentration had strong effects on the performance of UF treating LLRW. Therefore, it is suggested for industrial application that pretreatments to reduce EDTA or alkaline/ultrasonic washing involved in UF process were necessary to reduce the nuclide depositions on the membrane surfaces and irradiation dose of membrane surface.

  5. Cross flow ultrafiltration of Cr (VI) using MCM-41, MCM-48 and Faujasite (FAU) zeolite-ceramic composite membranes.

    Science.gov (United States)

    Basumatary, Ashim Kumar; Kumar, R Vinoth; Ghoshal, Aloke Kumar; Pugazhenthi, G

    2016-06-01

    This work describes the removal of Cr (VI) from aqueous solution in cross flow mode using MCM-41, MCM-48 and FAU zeolite membranes prepared on circular shaped porous ceramic support. Ceramic support was manufactured using locally available clay materials via a facile uni-axial compaction method followed by sintering process. A hydrothermal technique was employed for the deposition of zeolites on the ceramic support. The porosity of ceramic support (47%) is reduced by the formation of MCM-41 (23%), MCM-48 (22%) and FAU (33%) zeolite layers. The pore size of the MCM-41, MCM-48 and FAU membrane is found to be 0.173, 0.142, and 0.153 μm, respectively, which is lower than that of the support (1.0 μm). Cross flow ultrafiltration experiments of Cr (VI) were conducted at five different applied pressures (69-345 kPa) and three cross flow rates (1.11 × 10(-7) - 2.22 × 10(-7) m(3)/s). The filtration studies inferred that the performance of the fabricated zeolite composite membranes is optimum at the maximum applied pressure (345 kPa) and the highest rejection is obtained with the lowest cross flow rate (1.11 × 10(-7) m(3)/s) for all three zeolite membrane. The permeate flux of MCM-41, MCM-48 and FAU zeolite composite membranes are almost remained constant in the entire duration of the separation process. The highest removal of 82% is shown by FAU membrane, while MCM-41 and MCM-48 display 75% and 77% of Cr (VI) removal, respectively for the initial feed concentration of 1000 ppm with natural pH of the solution at an applied pressure of 345 kPa. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Modeling and Optimization of NLDH/PVDF Ultrafiltration Nanocomposite Membrane Using Artificial Neural Network-Genetic Algorithm Hybrid.

    Science.gov (United States)

    Arefi-Oskoui, Samira; Khataee, Alireza; Vatanpour, Vahid

    2017-07-10

    In this research, MgAl-CO 3 2- nanolayered double hydroxide (NLDH) was synthesized through a facile coprecipitation method, followed by a hydrothermal treatment. The prepared NLDHs were used as a hydrophilic nanofiller for improving the performance of the PVDF-based ultrafiltration membranes. The main objective of this research was to obtain the optimized formula of NLDH/PVDF nanocomposite membrane presenting the best performance using computational techniques as a cost-effective method. For this aim, an artificial neural network (ANN) model was developed for modeling and expressing the relationship between the performance of the nanocomposite membrane (pure water flux, protein flux and flux recovery ratio) and the affecting parameters including the NLDH, PVP 29000 and polymer concentrations. The effects of the mentioned parameters and the interaction between the parameters were investigated using the contour plot predicted with the developed model. Scanning electron microscopy (SEM), atomic force microscopy (AFM), and water contact angle techniques were applied to characterize the nanocomposite membranes and to interpret the predictions of the ANN model. The developed ANN model was introduced to genetic algorithm (GA) as a bioinspired optimizer to determine the optimum values of input parameters leading to high pure water flux, protein flux, and flux recovery ratio. The optimum values for NLDH, PVP 29000 and the PVDF concentration were determined to be 0.54, 1, and 18 wt %, respectively. The performance of the nanocomposite membrane prepared using the optimum values proposed by GA was investigated experimentally, in which the results were in good agreement with the values predicted by ANN model with error lower than 6%. This good agreement confirmed that the nanocomposite membranes prformance could be successfully modeled and optimized by ANN-GA system.

  7. Nutrient recovery from the dry grind process using sequential micro and ultrafiltration of thin stillage.

    Science.gov (United States)

    Arora, Amit; Dien, Bruce S; Belyea, Ronald L; Singh, Vijay; Tumbleson, M E; Rausch, Kent D

    2010-06-01

    The effectiveness of microfiltration (MF) and ultrafiltration (UF) for nutrient recovery from a thin stillage stream was determined. When a stainless steel MF membrane (0.1microm pore size) was used, the content of solids increased from 7.0% to 22.8% with a mean permeate flux rate of 45L/m(2)/h (LMH), fat increased and ash content decreased. UF experiments were conducted in batch mode under constant temperature and flow rate conditions. Permeate flux profiles were evaluated for regenerated cellulose membranes (YM1, YM10 and YM100) with molecular weight cut offs of 1, 10 and 100kDa. UF increased total solids, protein and fat and decreased ash in retentate stream. When permeate streams from MF were subjected to UF, retentate total solids concentrations similar to those of commercial syrup (23-28.8%) were obtained. YM100 had the highest percent permeate flux decline (70% of initial flux) followed by YM10 and YM1 membranes. Sequential filtration improved permeate flux rates of the YM100 membrane (32.6-73.4LMH) but the percent decline was also highest in a sequential MF+YM100 system. Protein recovery was the highest in YM1 retentate. Removal of solids, protein and fat from thin stillage may generate a permeate stream that may improve water removal efficiency and increase water recycling. Copyright 2010 Elsevier Ltd. All rights reserved.

  8. Effect of skim milk treated with high hydrostatic pressure on permeate flux and fouling during ultrafiltration.

    Science.gov (United States)

    Leu, Mathilde; Marciniak, Alice; Chamberland, Julien; Pouliot, Yves; Bazinet, Laurent; Doyen, Alain

    2017-09-01

    Ultrafiltration (UF) is largely used in the dairy industry to generate milk and whey protein concentrate for standardization of milk or production of dairy ingredients. Recently, it was demonstrated that high hydrostatic pressure (HHP) extended the shelf life of milk and improved rennet coagulation and cheese yield. Pressurization also modified casein micelle size distribution and promoted aggregation of whey proteins. These changes are likely to affect UF performance. Consequently, this study determined the effect of skim milk pressurization (300 and 600 MPa, 5 min) on UF performance in terms of permeate flux decline and fouling. The effect of HHP on milk proteins was first studied and UF was performed in total recycle mode at different transmembrane pressures to determine optimal UF operational parameters and to evaluate the effect of pressurization on critical and limiting fluxes. Ultrafiltration was also performed in concentration mode at a transmembrane pressure of 345 kPa for 130 or 140 min to evaluate the decline of permeate flux and to determine fouling resistances. It was observed that average casein micelle size decreased by 32 and 38%, whereas β-lactoglobulin denaturation reached 30 and 70% at 300 and 600 MPa, respectively. These results were directly related to UF performance because initial permeate fluxes in total recycle mode decreased by 25% at 300 and 600 MPa compared with nonpressurized milk, critical flux, and limiting flux, which were lower during UF of milk treated with HHP. During UF in concentration mode, initial permeate fluxes were 30% lower at 300 and 600 MPa compared with the control, but the total flux decline was higher for nonpressurized milk (62%) compared with pressure-treated milk (30%). Fouling resistances were similar, whatever the treatment, except at 600 MPa where irreversible fouling was higher. Characterization of the fouling layer showed that caseins and β-lactoglobulin were mainly involved in membrane fouling after UF of

  9. Effect of Diafiltration on Preparation of Fermented Mung Beans Concentrate as Probiotic Savory Flavor Through Ultrafiltration Membrane

    Directory of Open Access Journals (Sweden)

    Aspiyanto Aspiyanto

    2011-05-01

    Full Text Available Diafiltration by means of the ultrafiltration system of probiotic fermented Mung beans (Phaseolus radiatus L. concentrate has been performed to reduce or eliminate salts and smaller impurities than the nominal cut-off of the membrane of 20,000 nominal weight cut-off (NWCO. These processes have been conducted as an attempt in order to get a probiotic product with organoleptic acceptability, composition, and the optimal total lactic acid bacteria (LAB counts because the presence of salts will affect on the viability of LAB and the cell lysis of LAB and limit its utility in food products. Concentrate of probiotic mung beans was prepared through fermentation of LAB using inoculum of LAB consisting of Lactobacillus bulgaricus and Streptococcus thermophylus (1 : 1 on fermented mung beans extract inoculated by inoculum of Rhizopus–C1 in rice substrates at salt condition. Ultrafiltration and diafiltration modes have been carried out at flow rate of 8.77 Liter/minute, room temperature and the pressure of 5 bar (0 to 79.7 minutes and 7 bar (0-154.5 minutes with the ratio of the volume of pure water to the volume of initial feed (number of diavolume, Nd of 0, 0.25, 0.5, 0.75, 1.0 and 1.25, respectively. The experiment results based on total LAB counts as a probiotic product show that a high Nd can reduce the salt content but increase the total LAB counts. Nd of 1.0 results reduce the salt content which is equal to retentate, permeate, and the optimal total LAB counts. Ultrafiltration and diafiltration modes at the pressure of 7 bar and Nd of 1.0 give a retentate with total solid of 6.1355%, salt of 1.3515% and remove 86.15% of the salt from probiotic fermented mung beans concentrate and total LAB counts of 10.73 log cycles. Meanwhile, the permeate obtained at this condition results in flux value of 10.83 Liter/m2.hour with contents of total solid of 6.8199%, salt of 1.325% and total LAB counts of 5.49 log cycles.

  10. Practical experience of backwashing with SWRO permeate for UF fouling control

    KAUST Repository

    Li, Sheng; Heijman, Sebastiaan G J; Verberk, J. Q J C; Amy, Gary L.; Van Dijk, Johannis C.

    2013-01-01

    Effectiveness of seawater reverse osmosis (SWRO) permeate backwash on fouling control of seawater ultrafiltration was investigated at a pilot scale. A standard membrane module was used in this pilot to represent full-scale desalination plants. Results of the pilot show a good reproducibility. When the UF permeate was used for backwash, the frequency of chemically enhanced backwash (CEB) was around once per day. However, results of the pilot show that SWRO permeate backwashing could significantly reduce the CEB frequency. © 2013 Desalination Publications.

  11. Improvement of antifouling performances for modified PVDF ultrafiltration membrane with hydrophilic cellulose nanocrystal

    Science.gov (United States)

    Lv, Jinling; Zhang, Guoquan; Zhang, Hanmin; Zhao, Chuanqi; Yang, Fenglin

    2018-05-01

    Hydrophilic cellulose nanocrystal (CNC) was incorporated into hydrophobic poly(vinylidene fluoride) (PVDF) membrane via phase inversion process to improve membrane antifouling property. The effects of CNC on membrane morphology, hydrophilicity, permeability and antifouling property were investigated in-detail. Results indicated that the introduction of CNC into PVDF membrane enhanced the permeability by optimizing membrane microstructure and improving membrane hydrophilicity. A higher pure water flux of 206.9 L m-2 h-1 was achieved for CNC/PVDF membrane at 100 kPa, which was 20 times that of PVDF membrane (9.8 L m-2 h-1). In bovine serum albumin filtration measurements, the permeation flux and flux recovery ratio of CNC/PVDF membrane were increased remarkably, while the irreversible fouling-resistance of CNC/PVDF membrane decreased by 48.8%. These results indicated that the CNC/PVDF membrane possessed superior antifouling property due to the hydrophilicity of CNC that formed a hydration layer on the membrane surface to effectively reduce contaminants adsorption/deposition.

  12. Exploration of permeability and antifouling performance on modified cellulose acetate ultrafiltration membrane with cellulose nanocrystals.

    Science.gov (United States)

    Lv, Jinling; Zhang, Guoquan; Zhang, Hanmin; Yang, Fenglin

    2017-10-15

    Cellulose nanocrystals (CNCs) were introduced into cellulose diacetate (CDA) matrix via immerged phase-inversion process, aiming to improve the filtration and antifouling performance of CNCs/CDA blending membrane. The effects of CNCs on membrane morphologies, hydrophilicity, permeability and antifouling property were investigated. Results showed that the incorporation of CNCs into CDA membrane could effectively enhance the permeability and antifouling property of CNCs/CDA blending membrane by optimizing membrane microstructure and improving membrane hydrophilicity. A high pure water flux of 173.8L/m 2 h was achieved for the CNCs/CDA blending membrane at 200KPa, which is 24 times that of the CDA membrane (7.2L/m 2 h). The bovine serum albumin (BSA) adsorption amount of the CNCs/CDA blending membrane decreased about 48% compared to that of the CDA membrane. Additionally, the CNCs/CDA blending membrane exhibited better antifouling performance with the flux recovery ratio (FRR) of 89.5% after three fouling cycles, compared to 59.7% for the CDA membrane. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Flux, rejection and fouling during microfiltration and ultrafiltration of sugar palm sap using a pilot plant scale

    Directory of Open Access Journals (Sweden)

    Wanichapichart, P.

    2006-07-01

    Full Text Available The possibility of using a pilot plant scale microfiltration (MF and ultrafiltration (UF to clarify and reduce number of bacteria, yeast and mould of sugar palm sap was studied. The membrane used was multi channel tubular ceramic membrane (ZrO2-TiO2 with membrane pore size 0.2 and 0.1 μm and molecular weight cut off (MWCO 300 and 50 kDa for microfiltration and ultrafiltration respectively. The experiment was carried out to investigate the rejection of the components in sugar palm sap, permeate flux and fouling characteristics. The results showed that the turbidity, the total solid, the viscosity and the numbers of bacteria, yeast and mould in the permeate obtained by MF and UF were reduced significantly compared to those of fresh sugar palm sap. The total soluble solid, total sugar, reducing sugar and pH were not affected by MF and UF. The permeate fluxes for all membranes were reduced greatly as the volume concentration ratio (VCR increased due to severe fouling. The irreversible fouling on membrane surface and/or inside the membrane tended to increase with increasing membrane pore size or MWCO. The result also suggested that protein and small particle in the sugar palm sap were probably responsible for the internal fouling of large pore size membrane. According to the physical, chemical and microorganism quality results, both MF and UF showed the potential use for improving the quality of sugar palm sap but flux reduction due to fouling was a major problem affecting the process performance.

  14. Synthesis Polysulfone-Acetylethanol Ultrafiltration Membranes. Application to Oily Wastewater Treatment

    OpenAIRE

    Masuelli, Martin Alberto

    2016-01-01

    Chemical functionalization of polymers after the synthesis of membranes has great importance for various applications separative processes of industrial or environmental interest. Polysulfone (PSf) is one of the most applied polymers for separative processes used especially in membrane technology, due to its excellent chemical, mechanical and thermal properties. The functionalization of PSf makes it very attractive to give special characteristics due to their high hydrophobicity and membrane ...

  15. Novel Fouling-Reducing Coatings for Ultrafiltration, Nanofiltration, and Reverse Osmosis Membranes

    Energy Technology Data Exchange (ETDEWEB)

    Benny Freeman

    2008-08-31

    Polymeric membranes could potentially be the most flexible and viable long-term strategy for treatment of produced water from oil and gas production. However, widespread use of membranes, including reverse osmosis (RO) membranes, for produced water purification is hindered due to fouling caused by the impurities present in the water. Fouling of RO membranes is likely caused by surface properties including roughness, hydrophilicity, and charge, so surface modification is the most widely considered approach to improve the fouling properties of current RO membranes. This project focuses on two main approaches to surface modification: coating and grafting. Hydrophilic coating and grafting materials based on poly(ethylene glycol) (PEG) are applied to commercial RO membranes manufactured by Dow FilmTec and GE. Crossflow filtration experiments are used to determine the fouling resistance of modified membranes, and compare their performance to that of unmodified commercial RO membranes. Grafting and coating are shown to be two alternative methods of producing modified membranes with improved fouling resistance.

  16. The Modified Fouling Index Ultrafiltration constant flux for assessing particulate/colloidal fouling of RO systems

    KAUST Repository

    Salinas-Rodriguez, Sergio G.

    2015-02-18

    Reliable methods for measuring and predicting the fouling potential of reverse osmosis (RO) feed water are important in preventing and diagnosing fouling at the design stage, and for monitoring pre-treatment performance during plant operation. The Modified Fouling Index Ultrafiltration (MFI-UF) constant flux is a significant development with respect to assessing the fouling potential of RO feed water. This research investigates (1) the variables influencing the MFI-UF test at constant flux filtration (membrane pore size, membrane material, flux rate); and (2) the application of MFI-UF into pre-treatment assessment and RO fouling estimation. The dependency of MFI on flux, means that to assess accurately particulate fouling in RO systems, the MFI should be measured at a flux similar to a RO system (close to 20 L/m2/h) or extrapolated from higher fluxes. The two studied membrane materials showed reproducible results; 10% for PES membranes and 6.3% for RC membranes. Deposition factors (amount of particles that remain on the surface of membrane) were measured in a full-scale plant ranging between 0.2 and 0.5. The concept of “safe MFI” is presented as a guideline for assessing pre-treatment for RO systems.

  17. Carbon dioxide nucleation as a novel cleaning method for ultrafiltration membranes

    KAUST Repository

    Al Ghamdi, Mohanned

    2016-01-01

    will become in a supersaturated state and bubbles will start to nucleate on the surface of the membrane and its pores from this solution resulting in the removal of the fouling material deposited on the membrane. Different compositions of fouling solutions

  18. Enzyme immobilization by fouling in ultrafiltration membranes: Impact of membrane configuration and type on flux behavior and biocatalytic conversion efficacy

    DEFF Research Database (Denmark)

    Luo, Jianquan; Meyer, Anne S.; Jonsson, Gunnar Eigil

    2014-01-01

    Enzyme-immobilization in membranes accomplished by fostering membrane fouling was evaluated. Four different membrane configurations and five membranes were compared for immobilization of alcohol dehydrogenase (ADH) in terms of enzyme loading, permeate flux and final biocatalytic conversion...... and PLGC regenerated cellulose membranes. With these two highly hydrophilic membranes, the ADH enzyme activity was fully retained even after 24h of storage of the membrane. Filtration blocking and resistance models were used to analyze the fouling/immobilization mechanisms and give explanations...... for the different results. The work confirms that fouling-induced enzyme immobilization is a promising option for enhancing biocatalytic productivity, and highlights the significance of the membrane type and configuration for optimal performance....

  19. FTIR, XRD and DSC studies of nanochitosan, cellulose acetate and polyethylene glycol blend ultrafiltration membranes.

    Science.gov (United States)

    Vinodhini, P Angelin; K, Sangeetha; Thandapani, Gomathi; P N, Sudha; Jayachandran, Venkatesan; Sukumaran, Anil

    2017-11-01

    In the present work, a series of novel nanochitosan/cellulose acetate/polyethylene glycol (NCS/CA/PEG) blend flat sheet membranes were fabricated in different ratios (1:1:1, 1:1:2, 2:1:1, 2:1:2, 1:2:1, 2:2:1) in a polar solvent of N,N'-dimethylformamide (DMF) using the most popular phase inversion method. Nanochitosan was prepared by the ionotropic gelation method and its average particle size has been analyzed using Dynamic Light Scattering (DLS) method. The effect of blending of the three polymers was investigated using FTIR and XRD studies. FTIR results confirmed the formation of well-blended membranes and the XRD analysis revealed enhanced amorphous nature of the membrane ratio 2:1:2. DSC study was conducted to find out the thermal behavior of the blend membranes and the results clearly indicated good thermal stability and single glass transition temperature (T g ) of all the prepared membranes. Asymmetric nature and rough surface morphology was confirmed using SEM analysis. From the results it was evident that the blending of the polymers with higher concentration of nanochitosan can alter the nature of the resulting membranes to a greater extent and thus amorphous membranes were obtained with good miscibility and compatibility. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Studies on carboxylated graphene oxide incorporated polyetherimide mixed matrix ultrafiltration membranes

    Energy Technology Data Exchange (ETDEWEB)

    Kaleekkal, Noel Jacob, E-mail: noeljacob89@gmail.com [Membrane Laboratory, Department of Chemical Engineering, ACT, Anna University, Chennai, 600025 (India); Thanigaivelan, A., E-mail: thanichemstar@gmail.com [Membrane Laboratory, Department of Chemical Engineering, ACT, Anna University, Chennai, 600025 (India); Rana, Dipak, E-mail: rana@uottawa.ca [Department of Chemical and Biological Engineering, University of Ottawa, 161 Louis Pasteur Private, Ottawa, Ontario, K1N 6N5 (Canada); Mohan, D., E-mail: mohantarun@gmail.com [Membrane Laboratory, Department of Chemical Engineering, ACT, Anna University, Chennai, 600025 (India)

    2017-01-15

    In this work the graphene oxide prepared by the modified Hummers’ method was effectively carboxylated. These carboxylated graphene oxide (c-GO) microsheets was characterized by X-ray diffraction analysis, Raman shift, zeta potential, and their morphology was observed using a high resolution scanning/transmission electron microscopy. Polyetherimide mixed matrix membranes (MMMs) were fabricated by the non-solvent induced phase separation technique with varying concentration of this microsheet. The presence of these microsheets on the membrane surface was confirmed by Fourier transform infrared spectroscopy, Raman spectroscopy and could also be confirmed visually by optical images. The membranes were further characterized; they showed a greater water flux, higher porosity, and sufficient thermal stability. Incorporation of these microsheets improved the hydrophilicity of the membrane confirmed by the lower contact angle values, which in turn explained the lower interfacial free energy, the increase in work of adhesion, the higher solid-vapor free energy and the spreading coefficient. Membranes loaded with 0.3 wt% of c-GO showed a flux recovery of 94% and only a small flux decline even after 180 min of filtration of humic acid (HA) solution. The efficiency of these membranes in removal of HA, toxic metal ions was also investigated. The bacterial anti-adhesion property of c-GO in the membranes was also explored using Escherichia coli, as a model bio-foulant. The charge of the microsheets and their unique architecture imparts higher hydrophilicity and greater fouling resistance along with improved permeation flux when incorporated into the polymer matrix. - Highlights: • Novel membranes by incorporating carboxylated GO into polyetherimide matrix. • Modified membranes exhibited greater porosity, flux and high humic acid rejection. • Nanoplatelets improved the flux recovery ratio to >94%. • Liquid phase polymer based retention utilized for toxic heavy metal

  1. Ceramic Ultrafiltration of Marine Algal Solutions: A Comprehensive Study

    KAUST Repository

    Dramas, Laure

    2014-01-01

    understanding of UF membrane fouling caused by algal organic matter (AOM) is needed, in order to adjust the filtration conditions during algal bloom events. Polymeric MF/UF membranes are already widely used for RO pretreatment, but ceramic UF membranes can also

  2. PERFORMANCE AND SELECTIVITY OF CERAMIC MEMBRANES IN THE ULTRAFILTRATION OF MODEL EMULSION IN SALINE

    Directory of Open Access Journals (Sweden)

    Konrad ĆWIRKO

    2017-04-01

    Full Text Available Oily wastewaters from different onshore and offshore installations and from maritime transport pose a serious threat to the environment so they must be treated by multistage separation also including membrane processes. The main advantages of such membranes are high performance and selectivity, high resistance for temperature and pressure, resistance for acids, bases and solvents, long service life and for application – significant reduction of industries and transport environmental impact. This work presents the results of the process of separation of oil from the emulsion with NaCl addition. Research was performed with a use of laboratory installation with ceramic 300 kDa membrane. The analysis concerned performance and selectivity of a membrane in the function of time and test results have been subsequently compared with the requirements of the IMO.

  3. Comparative Evaluation of Ultrafiltration/Microfiltration Membranes for Removal of Nitrocellulose (NC) Fines from Wastewater

    National Research Council Canada - National Science Library

    Kim, Byung

    1997-01-01

    .... In Phase II, a pilot-scale crossflow membrane filtration system was constructed to: (1) investigate the concentration polarization and fouling mechanism caused by NC fines during crossflow filtration of NC wastewater, (2...

  4. Application of Combined Cake Filtration-Complete Blocking Model to Ultrafiltration of Skim Milk

    Directory of Open Access Journals (Sweden)

    Mansoor Kazemimoghadam

    2017-10-01

    Full Text Available Membrane ultrafiltration (UF is widely used in dairy industries like milk concentration and dehydration processes. The limiting factor of UF systems is fouling which is defined as the precipitation of solutes in the form of a cake layer on the surface of the membrane. In this study, the combined cake filtration-complete blocking model was compared to cake filtration mechanism for flux data through ultrafiltration of skim milk at constant flow rate. The resistance data also was modeled using cake filtration model and standard blocking model. The effect of different trans-membrane pressures and temperatures on flux decline was then investigated. Based on the results obtained here, the combined complete blocking-cake formation model was in excellent agreement with experimental data. The cake filtration model also provided good data fits and can be applied to solutions whose solutes tend to accumulate on the surface of the membrane in the form of a cake layer. With increasing pressure, the differences between the model and experimental data increased.

  5. Impact of ultrafiltration and nanofiltration of an industrial fish protein hydrolysate on its bioactive properties.

    Science.gov (United States)

    Picot, Laurent; Ravallec, Rozenn; Fouchereau-Péron, Martine; Vandanjon, Laurent; Jaouen, Pascal; Chaplain-Derouiniot, Maryse; Guérard, Fabienne; Chabeaud, Aurélie; Legal, Yves; Alvarez, Oscar Martinez; Bergé, Jean-Pascal; Piot, Jean-Marie; Batista, Irineu; Pires, Carla; Thorkelsson, Gudjon; Delannoy, Charles; Jakobsen, Greta; Johansson, Inez; Bourseau, Patrick

    2010-08-30

    Numerous studies have demonstrated that in vitro controlled enzymatic hydrolysis of fish and shellfish proteins leads to bioactive peptides. Ultrafiltration (UF) and/or nanofiltration (NF) can be used to refine hydrolysates and also to fractionate them in order to obtain a peptide population enriched in selected sizes. This study was designed to highlight the impact of controlled UF and NF on the stability of biological activities of an industrial fish protein hydrolysate (FPH) and to understand whether fractionation could improve its content in bioactive peptides. The starting fish protein hydrolysate exhibited a balanced amino acid composition, a reproducible molecular weight (MW) profile, and a low sodium chloride content, allowing the study of its biological activity. Successive fractionation on UF and NF membranes allowed concentration of peptides of selected sizes, without, however, carrying out sharp separations, some MW classes being found in several fractions. Peptides containing Pro, Hyp, Asp and Glu were concentrated in the UF and NF retentates compared to the unfractionated hydrolysate and UF permeate, respectively. Gastrin/cholecystokinin-like peptides were present in the starting FPH, UF and NF fractions, but fractionation did not increase their concentration. In contrast, quantification of calcitonin gene-related peptide (CGRP)-like peptides demonstrated an increase in CGRP-like activities in the UF permeate, relative to the starting FPH. The starting hydrolysate also showed a potent antioxidant and radical scavenging activity, and a moderate angiotensin-converting enzyme (ACE)-1 inhibitory activity, which were not increased by UF and NF fractionation. Fractionation of an FPH using membrane separation, with a molecular weight cut-off adapted to the peptide composition, may provide an effective means to concentrate CGRP-like peptides and peptides enriched in selected amino acids. The peptide size distribution observed after UF and NF fractionation

  6. Experimental investigation and modeling of industrial oily wastewater treatment using modified polyethersulfone ultrafiltration hollow fiber membranes

    International Nuclear Information System (INIS)

    Salahi, Abdolhamid; Mohammadi, Toraj; Behbahani, Reza Mosayebi; Hemmati, Mahmood

    2015-01-01

    Hollow fiber membranes were prepared from polyethersulfone/additives/NMP and DMSO system via phase inversion induced by precipitation in non-solvent coagulation bath. The interaction effects of polyethylene-glycol (PEG), propionic-acid (PA), Tween-20, PEG molecular weight and polyvinyl-pyrrolidone (PVP) on morphology and performance of synthesized membranes were investigated. Taguchi method (L 16 orthogonal array) was used initially to plan a minimum number of experiments. 32 membranes were synthesized (with two replications) and their permeation flux and TOC rejection properties to oily wastewater treatment were studied. The obtained results indicated that addition of PA to spinning dope decreases flux while it increases TOC rejection of prepared membranes. Also, the result shows that addition of PVP, Tween-20 and PEG content in spinning dope enhances permeation flux while reducing TOC rejection. The obtained results indicated that the synthesized membranes was effective and suitable for treatment of the oily wastewater to achieve up to 92.6, 98.2, and 98.5% removal of TOC, TSS, and OGC, respectively with a flux of 247.19 L/(m 2 h). Moreover, Hermia's models were used for permeation flux decline prediction. Experimental data and models predictions were compared. The results showed that there is reasonable agreement between experimental data and the cake layer model followed by the intermediate blocking model

  7. Experimental investigation and modeling of industrial oily wastewater treatment using modified polyethersulfone ultrafiltration hollow fiber membranes

    Energy Technology Data Exchange (ETDEWEB)

    Salahi, Abdolhamid; Mohammadi, Toraj [Iran University of Science and Technology (IUST), Tehran (Iran, Islamic Republic of); Behbahani, Reza Mosayebi [Petroleum University of Technology (PUT), Ahwaz (Iran, Islamic Republic of); Hemmati, Mahmood [Research Institute of Petroleum Industry, Tehran (Iran, Islamic Republic of)

    2015-06-15

    Hollow fiber membranes were prepared from polyethersulfone/additives/NMP and DMSO system via phase inversion induced by precipitation in non-solvent coagulation bath. The interaction effects of polyethylene-glycol (PEG), propionic-acid (PA), Tween-20, PEG molecular weight and polyvinyl-pyrrolidone (PVP) on morphology and performance of synthesized membranes were investigated. Taguchi method (L{sub 16} orthogonal array) was used initially to plan a minimum number of experiments. 32 membranes were synthesized (with two replications) and their permeation flux and TOC rejection properties to oily wastewater treatment were studied. The obtained results indicated that addition of PA to spinning dope decreases flux while it increases TOC rejection of prepared membranes. Also, the result shows that addition of PVP, Tween-20 and PEG content in spinning dope enhances permeation flux while reducing TOC rejection. The obtained results indicated that the synthesized membranes was effective and suitable for treatment of the oily wastewater to achieve up to 92.6, 98.2, and 98.5% removal of TOC, TSS, and OGC, respectively with a flux of 247.19 L/(m{sup 2}h). Moreover, Hermia's models were used for permeation flux decline prediction. Experimental data and models predictions were compared. The results showed that there is reasonable agreement between experimental data and the cake layer model followed by the intermediate blocking model.

  8. Influence of surface properties of filtration-layer metal oxide on ceramic membrane fouling during ultrafiltration of oil/water emulsion

    KAUST Repository

    Lu, Dongwei

    2016-04-01

    In this work, ceramic ultrafiltration membranes deposited with different metal oxides (i.e., TiO2, Fe2O3, MnO2, CuO, and CeO2) of around 10 nm in thickness and similar roughness were tested for O/W emulsion treatment. Distinct membrane fouling tendency was observed, which closely correlated to the properties of the filtration-layer metal oxides (i.e. surface hydroxyl groups, hydrophilicity, surface charge, and adhesion energy for oil droplets). In consistent with the distinct bond strength of the surface hydroxyl groups, hydrophilicity of these common metal oxides are quite different. The differences in hydrophilicity consequently lead to different adhesion of these metal oxides towards oil droplets which consists very well with irreversible membrane fouling tendency. In addition, the surface charge of the metal oxide opposite to that of emulsion can help to alleviate irreversible membrane fouling in ultrafiltration. Highly hydrophilic Fe2O3 with lowest fouling tendency could be a potential filtration-layer material for the fabrication/modification of ceramic membranes for O/W emulsion treatment. To the best of our knowledge, this is the first study clearly showing the correlations between surface properties of filtration-layer metal oxides and ceramic membrane fouling tendency by O/W emulsion.

  9. Influence of Surface Properties of Filtration-Layer Metal Oxide on Ceramic Membrane Fouling during Ultrafiltration of Oil/Water Emulsion.

    Science.gov (United States)

    Lu, Dongwei; Zhang, Tao; Gutierrez, Leo; Ma, Jun; Croué, Jean-Philippe

    2016-05-03

    In this work, ceramic ultrafiltration membranes deposited with different metal oxides (i.e., TiO2, Fe2O3, MnO2, CuO, and CeO2) of around 10 nm in thickness and similar roughness were tested for O/W emulsion treatment. A distinct membrane fouling tendency was observed, which closely correlated to the properties of the filtration-layer metal oxides (i.e., surface hydroxyl groups, hydrophilicity, surface charge, and adhesion energy for oil droplets). Consistent with the distinct bond strength of the surface hydroxyl groups, hydrophilicity of these common metal oxides is quite different. The differences in hydrophilicity consequently lead to different adhesion of these metal oxides toward oil droplets, consistent with the irreversible membrane fouling tendency. In addition, the surface charge of the metal oxide opposite to that of emulsion can help to alleviate irreversible membrane fouling in ultrafiltration. Highly hydrophilic Fe2O3 with the lowest fouling tendency could be a potential filtration-layer material for the fabrication/modification of ceramic membranes for O/W emulsion treatment. To the best of our knowledge, this is the first study clearly showing the correlations between surface properties of filtration-layer metal oxides and ceramic membrane fouling tendency by O/W emulsion.

  10. Influence of surface properties of filtration-layer metal oxide on ceramic membrane fouling during ultrafiltration of oil/water emulsion

    KAUST Repository

    Lu, Dongwei; Zhang, Tao; Gutierrez, Leo; Ma, Jun; Croue, Jean-Philippe

    2016-01-01

    In this work, ceramic ultrafiltration membranes deposited with different metal oxides (i.e., TiO2, Fe2O3, MnO2, CuO, and CeO2) of around 10 nm in thickness and similar roughness were tested for O/W emulsion treatment. Distinct membrane fouling tendency was observed, which closely correlated to the properties of the filtration-layer metal oxides (i.e. surface hydroxyl groups, hydrophilicity, surface charge, and adhesion energy for oil droplets). In consistent with the distinct bond strength of the surface hydroxyl groups, hydrophilicity of these common metal oxides are quite different. The differences in hydrophilicity consequently lead to different adhesion of these metal oxides towards oil droplets which consists very well with irreversible membrane fouling tendency. In addition, the surface charge of the metal oxide opposite to that of emulsion can help to alleviate irreversible membrane fouling in ultrafiltration. Highly hydrophilic Fe2O3 with lowest fouling tendency could be a potential filtration-layer material for the fabrication/modification of ceramic membranes for O/W emulsion treatment. To the best of our knowledge, this is the first study clearly showing the correlations between surface properties of filtration-layer metal oxides and ceramic membrane fouling tendency by O/W emulsion.

  11. Crude biodiesel refining using membrane ultra-filtration process: An environmentally benign process

    Directory of Open Access Journals (Sweden)

    I.M. Atadashi

    2015-12-01

    Full Text Available Ceramic membrane separation system was developed to simultaneously remove free glycerol and soap from crude biodiesel. Crude biodiesel produced was ultra-filtered by multi-channel tubular membrane of the pore size of 0.05 μm. The effects of process parameters: transmembrane pressure (TMP, bar, temperature (°C and flow rate (L/min on the membrane system were evaluated. The process parameters were then optimized using Central Composite Design (CCD coupled with Response Surface Methodology (RSM. The best retention coefficients (%R for free glycerol and soap were 97.5% and 96.6% respectively. Further, the physical properties measured were comparable to those obtained in ASTMD6751-03 and EN14214 standards.

  12. Removal of phenol from synthetic waste water using Gemini micellar-enhanced ultrafiltration (GMEUF)

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wenxiang [MOE Key Laboratory of Regional Energy and Environmental Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China); Huang, Guohe, E-mail: huang@iseis.org [MOE Key Laboratory of Regional Energy and Environmental Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China); Wei, Jia [Faculty of Engineering and Applied Science, University of Regina, Regina, Saskatchewan, Canada S4S 0A2 (Canada); Li, Huiqin; Zheng, Rubing; Zhou, Ya [MOE Key Laboratory of Regional Energy and Environmental Systems Optimization, Resources and Environmental Research Academy, North China Electric Power University, Beijing 102206 (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Gemini surfactant micellar enhanced ultrafiltration was used to remove phenol. Black-Right-Pointing-Pointer The effect of different hydrophilic head groups of surfactant was analyzed. Black-Right-Pointing-Pointer SEM, ATR-FTIR and mercury porosimeter were applied to elucidate membrane fouling. Black-Right-Pointing-Pointer Gemini surfactant had superior performance in comparing with conventional surfactant. - Abstract: Comprehensive studies were conducted on the phenol wastewater ultrafiltration (UF) with the help of various concentrations of cationic Gemini surfactant (N1-dodecyl-N1,N1,N2,N2-tetramethyl-N2-octylethane-1,2-diaminium bromide, CG), conventional cationic surfactant (dodecyl trimethyl ammonium bromide, DTAB), anionic surfactant (sodium dodecyl sulfate, SDS) and nonionic surfactant ((dodecyloxy)polyethoxyethanol, Brij35). A flat sheet module with polyethersulfone (PES) membrane was employed in this investigation. The effects of feed concentration (phenol and surfactant) on the retention of phenol and surfactant, permeate flux and membrane fouling by micelles were evaluated. The distribution coefficient (D), the loading of the micelles (L{sub m}) and the equilibrium distribution constant (K) were also utilized to estimate the micellar-enhanced ultrafiltration ability for phenol. Scanning electron microscope (SEM), Fourier transform infrared spectrometer with attenuated total reflectance accessory (ATR-FTIR) and mercury porosimeter were applied to analyze membrane surface morphology, membrane material characteristics and membrane fouling for the original and fouled membranes. Based on the above analysis, the performance of the selected Gemini surfactant was proved superior in the following aspects: retention of phenol/surfactant (peak value is 95.8% for phenol retention), permeate flux and membrane fouling with respect to other conventional surfactants possessing equal alkyl chain length. These results demonstrated

  13. Ultrafiltration-based degumming of crude rice bran oil using a polymer membrane

    Energy Technology Data Exchange (ETDEWEB)

    Sehn, G.A.R.; GonCalves, L.A.G.; Ming, C.C.

    2016-07-01

    Membrane technology has been gaining momentum in industrial processes, especially in food technology. It is believed to simplify processes, reduce energy consumption, and eliminate pollutants. The objective was to study the performance of polyvinylidene fluoride (PVDF) and polyethersulfone (PES) polymeric membranes in the degumming of the miscella of crude rice bran oil by using a bench-scale tangential filtration module. In addition, oil miscella filtration techniques using hexane and anhydrous ethyl alcohol solvents were compared. All membranes showed the retention of phospholipids and high flow rates. However, the best performance was observed using the 50-kDa PVDF membrane in miscella hexane solvent, with a 95.5% retention of the phosphorus concentration (by a factor of 1.4), resulting in a permeate with 29 mg·kg−1 of phosphorus and an average flow rate of 48.1 L·m−2·h−1. This technology can be used as a low-pollution, economical alternative for the de-gumming of crude rice bran oil, being effective in the removal of hydratable and non-hydratable phospholipids, resulting in oils with a low phosphorus content. (Author)

  14. Impact of ozonation, anion exchange resin and UV/H2O2 pre-treatments to control fouling of ultrafiltration membrane for drinking water treatment.

    Science.gov (United States)

    Pramanik, Biplob Kumar; Pramanik, Sagor Kumar; Sarker, Dipok Chandra; Suja, Fatihah

    2017-06-01

    The effects of ozonation, anion exchange resin (AER) and UV/H 2 O 2 were investigated as a pre-treatment to control organic fouling (OF) of ultrafiltration membrane in the treatment of drinking water. It was found that high molecular weight (MW) organics such as protein and polysaccharide substances were majorly responsible for reversible fouling which contributed to 90% of total fouling. The decline rate increased with successive filtration cycles due to deposition of protein content over time. All pre-treatment could reduce the foulants of a Ultrafiltration membrane which contributed to the improvement in flux, and there was a greater improvement of flux by UV/H 2 O 2 (61%) than ozonation (43%) which in turn was greater than AER (23%) treatment. This was likely due to the effective removal/breakdown of high MW organic content. AER gave greater removal of biofouling potential components (such as biodegradable dissolved organic carbon and assimilable organic carbon contents) compared to UV/H 2 O 2 and ozonation treatment. Overall, this study demonstrated the potential of pre-treatments for reducing OF of ultrafiltration for the treatment of drinking water.

  15. EFFECTS OF PRESSURE AND TEMPERATURE ON ULTRAFILTRATION HOLLOW FIBER MEMBRANE IN MOBILE WATER TREATMENT SYSTEM

    Directory of Open Access Journals (Sweden)

    ROSDIANAH RAMLI

    2016-07-01

    Full Text Available In Sabah, Malaysia, there are still high probability of limited clean water access in rural area and disaster site. Few villages had been affected in Pitas due to improper road access, thus building a water treatment plant there might not be feasible. Recently, Kundasang area had been affected by earthquake that caused water disruption to its people due to the damage in the underground pipes and water tanks. It has been known that membrane technology brought ease in making mobile water treatment system that can be transported to rural or disaster area. In this study, hollow fiber membrane used in a mobile water treatment system due to compact and ease setup. Hollow fiber membrane was fabricated into small module at 15 and 30 fibers to suit the mobile water treatment system for potable water production of at least 80 L/day per operation. The effects of transmembrane pressure (TMP and feed water temperature were investigated. It was found that permeate flux increases by more than 96% for both 15 and 30 fiber bundles with increasing pressure in the range of 0.25 to 3.0 bar but dropped when the pressure reached maximum. Lower temperature of 17 to 18˚C increase the water viscosity by 15% from normal temperature of water at 24˚C, making the permeate flux decreases. The fabricated modules effectively removed 96% turbidity of the surface water sample tested.

  16. Exploring the structure-properties relationships of novel polyamide thin film composite membranes

    DEFF Research Database (Denmark)

    Briceño, Kelly; Javakhishvili, Irakli; Guo, Haofei

    Polysulfone (PSU) is a material widely used in the fabrication of membranes for ultrafiltration and as a support for nanofiltration and reverse osmosis membranes. Interfacial polymerization usually combines amine and acid chloride monomers for the fabrication of thin film composite membranes[1......] . However, only few publications describe it’s usage for the modification of supports for the fabrication of ultrafiltration membranes [2]. This research focuses on the modification of PSU supports to produce new ultrafiltration membranes. The advantages of interfacial polymerization in the fabrication...... of UF membranes includes: Negatively charged PSF surfaces that could be less prone to biofouling Scale up process for the modification of PSU. An alternative to costly and technically challenging processes as in situ interfacial polymerization [3]....

  17. Simultaneous nitrogen and organics removal using membrane aeration and effluent ultrafiltration in an anaerobic fluidized membrane bioreactor

    KAUST Repository

    Ye, Yaoli; Saikaly, Pascal; Logan, B.E.

    2017-01-01

    Dissolved methane and a lack of nutrient removal are two concerns for treatment of wastewater using anaerobic fluidized bed membrane bioreactors (AFMBRs). Membrane aerators were integrated into an AFMBR to form an Aeration membrane fluidized bed membrane bioreactor (AeMFMBR) capable of simultaneous removal of organic matter and ammonia without production of dissolved methane. Good effluent quality was obtained with no detectable suspended solids, 93±5% of chemical oxygen demand (COD) removal to 14±11 mg/L, and 74±8% of total ammonia (TA) removal to 12±3 mg-N/L for domestic wastewater (COD of 193±23 mg/L and TA of 49±5 mg-N/L) treatment. Nitrate and nitrite concentrations were always low (< 1 mg-N/L) during continuous flow treatment. Membrane fouling was well controlled by fluidization of the granular activated carbon (GAC) particles (transmembrane pressures maintained <3 kPa). Analysis of the microbial communities suggested that nitrogen removal was due to nitrification and denitrification based on the presence of microorganisms associated with these processes.

  18. Simultaneous nitrogen and organics removal using membrane aeration and effluent ultrafiltration in an anaerobic fluidized membrane bioreactor

    KAUST Repository

    Ye, Yaoli

    2017-08-03

    Dissolved methane and a lack of nutrient removal are two concerns for treatment of wastewater using anaerobic fluidized bed membrane bioreactors (AFMBRs). Membrane aerators were integrated into an AFMBR to form an Aeration membrane fluidized bed membrane bioreactor (AeMFMBR) capable of simultaneous removal of organic matter and ammonia without production of dissolved methane. Good effluent quality was obtained with no detectable suspended solids, 93±5% of chemical oxygen demand (COD) removal to 14±11 mg/L, and 74±8% of total ammonia (TA) removal to 12±3 mg-N/L for domestic wastewater (COD of 193±23 mg/L and TA of 49±5 mg-N/L) treatment. Nitrate and nitrite concentrations were always low (< 1 mg-N/L) during continuous flow treatment. Membrane fouling was well controlled by fluidization of the granular activated carbon (GAC) particles (transmembrane pressures maintained <3 kPa). Analysis of the microbial communities suggested that nitrogen removal was due to nitrification and denitrification based on the presence of microorganisms associated with these processes.

  19. Ultrafiltration-based degumming of crude rice bran oil using a polymer membrane

    Directory of Open Access Journals (Sweden)

    Sehn, G. A.R.

    2016-03-01

    Full Text Available Membrane technology has been gaining momentum in industrial processes, especially in food technology. It is believed to simplify processes, reduce energy consumption, and eliminate pollutants. The objective was to study the performance of polyvinylidene fluoride (PVDF and polyethersulfone (PES polymeric membranes in the degumming of the miscella of crude rice bran oil by using a bench-scale tangential filtration module. In addition, oil miscella filtration techniques using hexane and anhydrous ethyl alcohol solvents were compared. All membranes showed the retention of phospholipids and high flow rates. However, the best performance was observed using the 50-kDa PVDF membrane in miscella hexane solvent, with a 95.5% retention of the phosphorus concentration (by a factor of 1.4, resulting in a permeate with 29 mg·kg−1 of phosphorus and an average flow rate of 48.1 L·m−2·h−1. This technology can be used as a low-pollution, economical alternative for the de-gumming of crude rice bran oil, being effective in the removal of hydratable and non-hydratable phospholipids, resulting in oils with a low phosphorus content.La tecnología de membrana ha ido ganando impulso en los procesos industriales, especialmente en tecnología de los alimentos. Se piensa que simplifica los procesos, reduce el consumo de energía, y elimina contaminantes. El objetivo fué estudiar el rendimiento de las membranas poliméricas de fluoruro de polivinilo (PVDF y poliétersulfona (PES en el desgomado de miscelas de aceite de salvado de arroz crudo, mediante el uso de un módulo de filtración de escalado tangencial. Además, se compararon las técnicas de filtración de miscelas de aceite, utilizando como disolventes hexano y alcohol etílico anhidro. Todas las membranas mostraron retención de los fosfolípidos y altas tasas de flujo. Sin embargo, se observó un mejor rendimiento usando la membrana de PVDF de 50-kDa con hexano como disolvente, con una retención del 95

  20. A coagulation-powdered activated carbon-ultrafiltration - Multiple barrier approach for removing toxins from two Australian cyanobacterial blooms

    International Nuclear Information System (INIS)

    Dixon, Mike B.; Richard, Yann; Ho, Lionel; Chow, Christopher W.K.; O'Neill, Brian K.; Newcombe, Gayle

    2011-01-01

    Cyanobacteria are a major problem for the world wide water industry as they can produce metabolites toxic to humans in addition to taste and odour compounds that make drinking water aesthetically displeasing. Removal of cyanobacterial toxins from drinking water is important to avoid serious illness in consumers. This objective can be confidently achieved through the application of the multiple barrier approach to drinking water quality and safety. In this study the use of a multiple barrier approach incorporating coagulation, powdered activated carbon (PAC) and ultrafiltration (UF) was investigated for the removal of intracellular and extracellular cyanobacterial toxins from two naturally occurring blooms in South Australia. Also investigated was the impact of these treatments on the UF flux. In this multibarrier approach, coagulation was used to remove the cells and thus the intracellular toxin while PAC was used for extracellular toxin adsorption and finally the UF was used for floc, PAC and cell removal. Cyanobacterial cells were completely removed using the UF membrane alone and when used in conjunction with coagulation. Extracellular toxins were removed to varying degrees by PAC addition. UF flux deteriorated dramatically during a trial with a very high cell concentration; however, the flux was improved by coagulation and PAC addition.

  1. Evaluation of Removal Mechanisms in a Graphene Oxide-Coated Ceramic Ultrafiltration Membrane for Retention of Natural Organic Matter, Pharmaceuticals, and Inorganic Salts.

    Science.gov (United States)

    Chu, Kyoung Hoon; Fathizadeh, Mahdi; Yu, Miao; Flora, Joseph R V; Jang, Am; Jang, Min; Park, Chang Min; Yoo, Sung Soo; Her, Namguk; Yoon, Yeomin

    2017-11-22

    Functionalized graphene oxide (GO), derived from pure graphite via the modified Hummer method, was used to modify commercially available ceramic ultrafiltration membranes using the vacuum method. The modified ceramic membrane functionalized with GO (ceramic GO ) was characterized using a variety of analysis techniques and exhibited higher hydrophilicity and increased negative charge compared with the pristine ceramic membrane. Although the pure water permeability of the ceramic GO membrane (14.4-58.6 L/m 2 h/bar) was slightly lower than that of the pristine membrane (25.1-62.7 L/m 2 h/bar), the removal efficiencies associated with hydrophobic attraction and charge effects were improved significantly after GO coating. Additionally, solute transport in the GO nanosheets of the ceramic GO membrane played a vital role in the retention of target compounds: natural organic matter (NOM; humic acid and tannic acid), pharmaceuticals (ibuprofen and sulfamethoxazole), and inorganic salts (NaCl, Na 2 SO 4 , CaCl 2 , and CaSO 4 ). While the retention efficiencies of NOM, pharmaceuticals, and inorganic salts in the pristine membrane were 74.6%, 15.3%, and 2.9%, respectively, these increased to 93.5%, 51.0%, and 31.4% for the ceramic GO membrane. Consequently, the improved removal mechanisms of the membrane modified with functionalized GO nanosheets can provide efficient retention for water treatment under suboptimal environmental conditions of pH and ionic strength.

  2. Seawater ultrafiltration fouling control: Backwashing with demineralized water/SWRO permeate

    KAUST Repository

    Li, Sheng; Heijman, Sebastiaan G J; Verberk, J. Q J C; Amy, Gary L.; Van Dijk, Johannis C.

    2012-01-01

    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. © 2012 Elsevier B.V. All rights reserved.

  3. Seawater ultrafiltration fouling control: Backwashing with demineralized water/SWRO permeate

    KAUST Repository

    Li, Sheng

    2012-09-01

    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. © 2012 Elsevier B.V. All rights reserved.

  4. Removal of copper ions from aqueous solutions by means of micellar-enhanced ultrafiltration

    Directory of Open Access Journals (Sweden)

    Kowalska Izabela

    2017-01-01

    Full Text Available The aim of the study was to assess the usefulness of micellar–enhanced ultrafiltration (MEUF for removal of copper ions from water solutions in comparison with classic ultrafiltration process. The tests were conducted in a semi–pilot membrane installation with the use of ultrafiltration module KOCH/ROMICON® at a transmembrane pressure of 0.05 MPa. The effect of concentration of copper ions on ultrafiltration process efficiency was investigated. The second part of the tests concerned the removal of copper ions by MEUF under wide range of anionic surfactant concentration (0.25, 1, and 5 CMC (critical micelle concentration. Concentration of copper ions in model solutions was equal to 5, 20, and 50 mg Cu/L. Furthermore, the effect of surfactant leakage to the permeate side during filtration was evaluated. Conducted experiments confirmed effectiveness of MEUF in copper ions removal. For the highest copper concentration in the feed (i.e. 50 mg/L, the average concentration of copper ions in the permeate ranged from 1.2–4.7 mg Cu/L depending on surfactant concentration. During filtration experiments, UF module exhibited stable transport properties for model solutions containing copper. For the highest concentration of metal, the decrease of permeate flux did not exceed 11% after 60 minutes of filtration. In the presence of the surfactant, a slight deterioration of transport properties was observed.

  5. Effects of Wheat Gluten Hydrolysate and Its Ultrafiltration Fractions on Dough Properties and Bread Quality

    Directory of Open Access Journals (Sweden)

    Mouming Zhao

    2007-01-01

    Full Text Available Two fractions (50-K and permeate from a proteolytic hydrolysate (degree of hydrolysis, DH=3.8 % of wheat gluten were separated using ultrafiltration (UF membrane with molecular mass cut-off of 50 kDa. The effects of the wheat gluten hydrolysate (WGH and its UF fractions on the mixing behaviour and viscoelastic properties of wheat dough were presented. The WGH and its UF fractions modified the mixing properties of dough. The addition of these fractions improved the viscoelastic characteristics of wheat dough. A significant (p<0.05 effect of 50-K fraction on these characteristics of wheat dough was observed. After adding these fractions, the bread was considered acceptable by the sensory panel. Also, 50-K fraction resulted in significant (p<0.05 increase in the crumb firmness, while the bread made with wheat flour with WGH and permeate (P fraction showed softer crumbs compared to that of wheat flour. Moreover, these fractions had anti-staling properties for bread during storage. Hence, the wheat gluten hydrolysate and its UF fractions are the products with promising potential in the baking products.

  6. Study and optimization of the ultrasound-enhanced cleaning of an ultrafiltration ceramic membrane through a combined experimental-statistical approach.

    Science.gov (United States)

    Alventosa-deLara, E; Barredo-Damas, S; Alcaina-Miranda, M I; Iborra-Clar, M I

    2014-05-01

    Membrane fouling is one of the main drawbacks of ultrafiltration technology during the treatment of dye-containing effluents. Therefore, the optimization of the membrane cleaning procedure is essential to improve the overall efficiency. In this work, a study of the factors affecting the ultrasound-assisted cleaning of an ultrafiltration ceramic membrane fouled by dye particles was carried out. The effect of transmembrane pressure (0.5, 1.5, 2.5 bar), cross-flow velocity (1, 2, 3 ms(-1)), ultrasound power level (40%, 70%, 100%) and ultrasound frequency mode (37, 80 kHz and mixed wave) on the cleaning efficiency was evaluated. The lowest frequency showed better results, although the best cleaning performance was obtained using the mixed wave mode. A Box-Behnken Design was used to find the optimal conditions for the cleaning procedure through a response surface study. The optimal operating conditions leading to the maximum cleaning efficiency predicted (32.19%) were found to be 1.1 bar, 3 ms(-1) and 100% of power level. Finally, the optimized response was compared to the efficiency of a chemical cleaning with NaOH solution, with and without the use of ultrasound. By using NaOH, cleaning efficiency nearly triples, and it improves up to 25% by adding ultrasound. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Microstructured hollow fibers for ultrafiltration

    NARCIS (Netherlands)

    Culfaz, Pmar Zeynep; Culfaz, P.Z.; Rolevink, Hendrikus H.M.; van Rijn, C.J.M.; Lammertink, Rob G.H.; Wessling, Matthias

    2010-01-01

    Hollow fiber ultrafiltration membranes with a corrugated outer microstructure were prepared from a PES/PVP blend. The effect of spinning parameters such as air gap, take-up speed, polymer dope viscosity and coagulation value on the microstructure and membrane characteristics was investigated. Fibers

  8. Summary of the ultrafiltration, reverse osmosis, and adsorbents project

    International Nuclear Information System (INIS)

    Colvin, C.M.; Roberts, R.C.; Williams, M.K.

    1983-01-01

    The design for a medium-size (40 gal/min) ultrafiltration (UF) membrane unit includes a schematic diagram, capital and operating costs, a list and discussion of the radioisotopes tested and the results achieved, operating parameters, and characteristics of the available membrane configurations. The plant design for a reverse osmosis (RO) membrane unit includes a conceptual diagram, specifications for a RO unit producing 40 gal/min of permeated product, a list of radioisotopes tested on RO units and the rejections achieved, a discussion of the principal of RO, a discussion of the upper limits of cation and anion concentrations (there are no lower limits), a discussion of membrane configurations and porosities, a discussion of factors affecting membranes, a section on calculating the membrane area needed for a particular application, and capital and operating cost calculations. The design for an ion-exchange pilot plant includes a schematic diagram; flow, resin, and column specifications; impurity limits; and operating and capital costs. A short theoretical discussion and process description are also included. The design retains flexibility so that application to a specific stream can be determined

  9. Ultrafiltration of pegylated proteins

    Science.gov (United States)

    Molek, Jessica R.

    There is considerable clinical interest in the use of "second-generation" therapeutics produced by conjugation of a native protein with various polymers including polyethylene glycol (PEG). PEG--protein conjugates, so-called PEGylated proteins, can exhibit enhanced stability, half-life, and bioavailability. One of the challenges in the commercial production of PEGylated proteins is the purification required to remove unreacted polymer, native protein, and in many cases PEGylated proteins with nonoptimal degrees of conjugation. The overall objective of this thesis was to examine the use of ultrafiltration for the purification of PEGylated proteins. This included: (1) analysis of size-based separation of PEGylated proteins using conventional ultrafiltration membranes, (2) use of electrically-charged membranes to exploit differences in electrostatic interactions, and (3) examination of the effects of PEGylation on protein fouling. The experimental results were analyzed using appropriate theoretical models, with the underlying physical properties of the PEGylated proteins evaluated using size exclusion chromatography, capillary electrophoresis, dynamic light scattering, and reverse phase chromatography. PEGylated proteins were produced by covalent attachment of activated PEG to a protein via primary amines on the lysine residues. A simple model was developed for the reaction kinetics, which was used to explore the effect of reaction conditions and mode of operation on the distribution of PEGylated products. The effective size of the PEGylated proteins was evaluated using size exclusion chromatography, with appropriate correlations developed for the size in terms of the molecular weight of the native protein and attached PEG. The electrophoretic mobility of the PEGylated proteins were evaluated by capillary electrophoresis with the data in good agreement with a simple model accounting for the increase in protein size and the reduction in the number of protonated amine

  10. Evaluating the Efficiency of Different Microfiltration and Ultrafiltration Membranes Used as Pre-treatment for Reverse Osmosis Desalination of Red Sea Water

    KAUST Repository

    AlMashharawi, Samer

    2011-07-01

    With the increase in population density throughout the world and the growing water demand, innovative methods of providing safe drinking water are of a very high priority. In 2002, the United Nations stated in their millennium declaration that one of their priority goals was “To reduce by half, by the year 2015, the proportion of people who are unable to reach or to afford safe drinking water” [1]. This goal was set with high standards and requires a great deal of water treatment related research in the coming years. Since 1990’s, drinking water treatment via membrane filtration has been widely accepted as a feasible alternative to conventional drinking water treatment. Nowadays, membrane processes are used for separation applications in many industrial applications. Over the past two decades, there has been a rapid growth in the use of low-pressure membrane for drinking water production. These membrane systems are increasingly being accepted as feasible and sustainable technologies for drinking water treatment. Like any innovative process, it has limitations; the primary limitation is membrane fouling, a phenomenon of particles accumulation on the membrane surface and inside its pores. It has the ability to reduce the permeate flux so that higher pumping intensity is required to maintain a consistent volume of product and increasing the cleaning frequency. This project has investigated the rate of reduction in the flux and the increase of pumping intensity using different membranes. Low pressure membranes with three different pore sizes (0.1μm MF, 100kDa UF, and 50kDa UF) have been tested. Eight different filtration configurations have been applied to the membranes including the variation of coagulant (FeCl3) addition aiming mitigation fouling impact in order to maintain consistent permeate flux, while monitoring several water quality parameters before and after treatment such as turbidity, SDI15, total organic carbon (TOC) and particle size distribution

  11. Anti-diabetic and antihypertensive activities of two flaxseed protein hydrolysate fractions revealed following their simultaneous separation by electrodialysis with ultrafiltration membranes.

    Science.gov (United States)

    Doyen, Alain; Udenigwe, Chibuike C; Mitchell, Patricia L; Marette, André; Aluko, Rotimi E; Bazinet, Laurent

    2014-02-15

    Flaxseed protein hydrolysate has been fractionated by electrodialysis with two ultrafiltration membranes (20 and 50 kDa) stacked in the system for the recovery of two specific cationic peptide fractions (KCl-F1 and KCl-F2). After 360 min of treatment, peptide migration increased as a function of time in KCl compartments. Moreover, the use of two different ultrafiltration membrane allowed concentration of the 300-400 and 400-500 Da molecular weight range peptides in the KCl-F1 and KCl-F2 fractions, respectively, compared to the initial hydrolysate. After mass spectrometry analysis, higher amounts of low molecular weight peptides were recovered in the KCl-F2 compartment while relatively higher molecular weight peptides were more detected in the KCl-F1 compartment. Amino acid analysis showed that His, Lys and Arg were especially concentrated in the KCl compartments. Finally, glucose-transport assay demonstrated that the KCl-F2 fraction increased glucose uptake while oral administration of KCl-F1 and final FPH decreased systolic blood pressure. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Analysis of the membrane fouling on cross-flow ultrafiltration and microfiltration of soy sauce lees; Shoyuhiireden no kurosuforo roka ni okeru fauringu no kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Furukakwa, T. [Kikkoman Corporation, Chiba (Japan); Kobayashi, H.; Kokubo, K.; Watanabe, A. [Niigata University, Niigata (Japan). Graduate School of Science and Technology

    2000-05-10

    Although since the 1980's Japanese soy sauce manufactures have developed cross-flow membrane filtration systems to recover soy sauce from its lees, the mechanisms by which the membrane fouls during filtration have not been theoretically discussed. Calculated flux declines using a theoretical equation developed for cross-flow cake filtration were compared against experimental results involving the filtration of soy sauce lees using polysulfone ultrafiltration and micro filtration membranes. Membrane fouling due to the deposition and intrusion of soy sauce lees was evaluated from the hydraulic resistances of the membrane and the cake layer. Calculated flux declines with time agree with the experimental results. Specific resistance of the cake layer which is an adjustable parameter of the equation, decreases with increasing cross-flow velocity. Hydraulic resistance exhibited by the membranes is independent of feed flow velocity. However, the resistance of the cake layers decreases with increasing cross-flow velocity. This corresponds to the steady-state flux increase. In conclusion, the main cause of fouling in the filtration of soy sauce lees is cake layer formation. By using the cake filtration model for cross-flow, the flux decline with time during the filtration is capable of being predicted. (author)

  13. Ultrafiltration evaluation with depleted uranium oxide

    International Nuclear Information System (INIS)

    Weisbrod, K.R.; Schake, A.R.; Morgan, A.N.; Purdy, G.M.; Martinez, H.E.; Nelson, T.O.

    1998-03-01

    Scientists at the Los Alamos National Laboratory Plutonium Facility are using electrodissolution in neutral to alkaline solutions to decontaminate oralloy parts that have surface plutonium contamination. Ultrafiltration of the electrolyte stream removes precipitate so that the electrolyte stream to the decontamination fixture is precipitate free. This report describes small-scale laboratory ultrafiltration experiments that the authors performed to determine conditions necessary for full-scale operation of an ultrafiltration module. Performance was similar to what they observed in the ferric hydroxide system. At 12 psi transmembrane pressure, a shear rate of 12,000 sec -1 was sufficient to sustain membrane permeability. Ultrafiltration of uranium(VI) oxide appears to occur as easily as ultrafiltration of ferric hydroxide. Considering the success reported in this study, the authors plan to add ultrafiltration to the next decontamination system for oralloy parts

  14. Removal of a synthetic organic chemical by PAC-UF systems. II: Model application.

    Science.gov (United States)

    Matsui, Y; Colas, F; Yuasa, A

    2001-02-01

    This paper describes several application potentials with a recently developed model for predicting the synthetic organic chemical (SOC) removal by powdered activated carbon (PAC) adsorption during ultrafiltration (UF) and discusses the removal mechanism. The model was successfully applied, without any modification, to dead-end mode operation as well as to cross-flow mode operation, validating the assumption of the internal diffusion control mechanism and the continuously-stirred-tank-reactor (CSTR) concept. Even when UF was operated in a cross-flow mode, PAC added was re-circulating in suspension for only a short time. Then, solute uptake took place mostly by PAC immobilized in membrane tubes not only for dead-end operation but also for cross-flow operation. Therefore, cross-flow operation did not have any advantage regarding the SOC mass transfer on PAC in UF loop over dead-end operation. The model simulation implied that pulse PAC addition at the beginning of filtration cycle resulted better SOC removal than continuous PAC addition. However, for the pulse PAC addition mode, the model predicted somewhat lower effluent SOC concentration than the observed values, and the benefit of pulse PAC application in terms of reducing SOC over its continuous dosage was not confirmed. Longer detention time of PAC dosed in a pulse than continuously dosed PAC could possibly further decrease internal diffusivity.

  15. Pilot-scale ultrafiltration testing for the F and H area effluent treatment facility

    International Nuclear Information System (INIS)

    Kessler, J.L.

    1984-01-01

    An F and H Area Effluent Treatment Facility (F/H ETF) is being designed to treat low activity aqueous effluents which are produced from F and H Area daily operations. The treatment scheme for the F/H ETF will include pretreatment (pH adjustment and filtration) followed by Reverse Osmosis and/or Ion Exchange to remove dissolved species. Several alternative treatment processes are being considered for the F/H ETF. One of the alternatives in the pretreatment step is tubular Ultrafiltration (UF), using a dynamically formed zirconium oxide membrane supported on a porous stainless steel backing. Pilot-scale testing with a single membrane module (13 ft 2 area) and 200-Area effluent simulant has demonstrated that UF is a viable filtration option for the F/H ETF. UF testing at TNX has defined the operating conditions necessary for extended operation and also demonstrated excellent filtration performance (filtrate SDI 2 /day) flux and will provide excellent pretreatment for both reverse osmosis and ion exchange. 2 refs

  16. Protein bioseparation using ultrafiltration: theory, applications and new developments

    National Research Council Canada - National Science Library

    Ghosh, Raja

    2003-01-01

    ... membrane-based separation process. This book discusses how ultrafiltration could be used for protein bioseparation. There are several good books on protein bioseparation and indeed several others on ultrafiltration. However, there are relatively fewer books dealing specifically with protein bioseparation using ultrafiltration, in spite of this being an a...

  17. A New Concept of Ultrafiltration Fouling Control : Backwashing with Low Ionic Strength Water

    NARCIS (Netherlands)

    Li, S.

    2011-01-01

    Ultrafiltration (UF) is a proven technology in water treatment nowadays. However, fouling remains a major challenge in the operation of UF, especially in regard to colloidal NOM fouling. In general, a number of colloidal NOM fouling mechanisms may occur, such as adsorption, gel formation. Colloidal

  18. Evaluation of Ultrafiltration for Spacecraft Water Reuse

    Science.gov (United States)

    Pickering, Karen D.; Wiesner, Mark R.

    2001-01-01

    Ultrafiltration is examined for use as the first stage of a primary treatment process for spacecraft wastewater. It is hypothesized that ultrafiltration can effectively serve as pretreatment for a reverse osmosis system, removing the majority of organic material in a spacecraft wastewater. However, it is believed that the interaction between the membrane material and the surfactant found in the wastewater will have a significant impact on the fouling of the ultrafiltration membrane. In this study, five different ultrafiltration membrane materials are examined for the filtration of wastewater typical of that expected to be produced onboard the International Space Station. Membranes are used in an unstirred batch cell. Flux, organic carbon rejection, and recovery from fouling are measured. The results of this evaluation will be used to select the most promising membranes for further study.

  19. Seasonal variation of organic matter concentration and characteristics in the Maji ya Chai River (Tanzania): Impact on treatability by ultrafiltration

    KAUST Repository

    Aschermann, Geert

    2016-05-07

    Many waters in Tanzania exhibit high concentrations of organic matter and dissolved contaminants such as fluoride. Due to bacteria and virus removal, ultrafiltration (UF) is an attractive option for drinking water treatment, and when coupled with adsorbents, may compete with other established processes like nanofiltration (NF) for lower contaminant concentrations. The results presented here examine the characteristics and treatability of tropical natural organic matter (NOM) by UF as a function of seasonal variation. The Tanzanian river Maji ya Chai was sampled monthly during one year. The composition of NOM in Maji ya Chai River is influenced strongly by precipitation. Total organic carbon (TOC), specific ultraviolet absorbance (SUVA) and concentration of allochthonous organics substances (such as humic substances (HS)) are elevated in periods following high precipitation, while TOC is lower and contains more biopolymers in the dry seasons. UF experiments with two regenerated cellulose membranes of different molecular weight cut-off (MWCO, 5 and 10 kDa) were conducted. UF is able to remove 50–95% of TOC with a seasonal variability of 10–20%. Due to the remaining NOM in the water that would contribute to disinfection by-product formation and bacterial regrowth, the physically disinfected water is more applicable for point of use systems than distribution or storage.

  20. Effects of different pretreatments on the performance of ceramic ultrafiltration membrane during the treatment of oil sands tailings pond recycle water: a pilot-scale study.

    Science.gov (United States)

    Loganathan, Kavithaa; Chelme-Ayala, Pamela; El-Din, Mohamed Gamal

    2015-03-15

    Membrane filtration is an effective treatment method for oil sands tailings pond recycle water (RCW); however, membrane fouling and rapid decrease in permeate flux caused by colloids, organic matter, and bitumen residues present in the RCW hinder its successful application. This pilot-scale study investigated the impact of different pretreatment steps on the performance of a ceramic ultrafiltration (CUF) membrane used for the treatment of RCW. Two treatment trains were examined: treatment train 1 consisted of coagulant followed by a CUF system, while treatment train 2 included softening (Multiflo™ system) and coagulant addition, followed by a CUF system. The results indicated that minimum pretreatment (train 1) was required for almost complete solids removal. The addition of a softening step (train 2) provided an additional barrier to membrane fouling by reducing hardness-causing ions to negligible levels. More than 99% removal of turbidity and less than 20% removal of total organic carbon were achieved regardless of the treatment train used. Permeate fluxes normalized at 20 °C of 127-130 L/m(2) h and 111-118 L/m(2) h, with permeate recoveries of 90-93% and 90-94% were observed for the treatment trains 1 and 2, respectively. It was also found that materials deposited onto the membrane surface had an impact on trans-membrane pressure and influenced the required frequencies of chemically enhanced backwashes (CEBs) and clean-in-place (CIP) procedures. The CIP performed was successful in removing fouling and scaling materials such that the CUF performance was restored to baseline levels. The results also demonstrated that due to their low turbidity and silt density index values, permeates produced in this pilot study were suitable for further treatment by high pressure membrane processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Study on cross-flow ultrafiltration for the radioactive liquid waste treatment

    International Nuclear Information System (INIS)

    Jung, K. H.; Jo, E. S.; Lee, D. G.; Lee, G. W.; Jung, K. J.

    2000-01-01

    The effect of the UF membranes on permeate flux was investigated in the ultrafiltration of dodecane (0.1v%) / water emulsion and dodecane-SDS-water emulsion in view of the treatment of radioactive oily emulsion liquid waste in the future. For variety of membranes, experiments in cross-flow modes have been performed at various pressure and different cross-flow velocities. Permeate flux decreased with the time and reached a constant steady-state value. Steady-state flux was found to be dependent by the hydrodynamic conditions but independent by the pressure. Flux decrease and rates of permeate flow resistance change have been analysed using a formulation of the equations illustrating the method of resistance mechanism recognition

  2. Quantification of biomolecules in herring (Clupea harengus) industry processing waters and their recovery using electroflocculation and ultrafiltration

    DEFF Research Database (Denmark)

    Osman, Ali; Gringer, Nina; Svendsen, Tore

    2015-01-01

    Four types of herring industry processing waters; refrigerated sea water (RSW), storage water (SW), processing water from cutting (PW) and pre-salting brines (SB) were subjected to chemical characterization and biomolecule recovery using electroflocculation (EF) and ultrafiltration (UF). The high......Four types of herring industry processing waters; refrigerated sea water (RSW), storage water (SW), processing water from cutting (PW) and pre-salting brines (SB) were subjected to chemical characterization and biomolecule recovery using electroflocculation (EF) and ultrafiltration (UF...

  3. How Do Polyethylene Glycol and Poly(sulfobetaine) Hydrogel Layers on Ultrafiltration Membranes Minimize Fouling and Stay Stable in Cleaning Chemicals?

    KAUST Repository

    Le, Ngoc Lieu

    2017-05-18

    We compare the efficiency of grafting polyethylene glycol (PEG) and poly(sulfobetaine) hydrogel layer on poly(ether imide) (PEI) hollow-fiber ultrafiltration membrane surfaces in terms of filtration performance, fouling minimization and stability in cleaning solutions. Two previously established different methods toward the two different chemistries (and both had already proven to be suited to reduce fouling significantly) are applied to the same PEI membranes. The hydrophilicity of PEI membranes is improved by the modification, as indicated by the change of contact angle value from 89° to 68° for both methods, due to the hydration layer formed in the hydrogel layers. Their pure water flux declines because of the additional permeation barrier from the hydrogel layers. However, these barriers increase protein rejection. In the exposure at a static condition, grafting PEG or poly(sulfobetaine) reduces protein adsorption to 23% or 11%, respectively. In the dynamic filtration, the hydrogel layers minimizes the flux reduction and increases the reversibility of fouling. Compared to the pristine PEI membrane that can recover its flux to 42% after hydraulic cleaning, the PEG and poly(sulfobetaine) grafted membranes can recover their flux up to 63% and 94%, respectively. Stability tests show that the poly(sulfobetaine) hydrogel layer is stable in acid, base and chlorine solutions, whereas the PEG hydrogel layer suffers alkaline hydrolysis in base and oxidation in chlorine conditions. With its chemical stability and pronounced capability of minimizing fouling, especially irreversible fouling, protective poly(sulfobetaine) hydrogel layers have great potential for various membrane-based applications.

  4. Elaboration, characterization and application of polysulfone and polyacrylic acid blends as ultrafiltration membranes for removal of some heavy metals from water.

    Science.gov (United States)

    Mbareck, Chamekh; Nguyen, Quang Trong; Alaoui, Ouafa Tahiri; Barillier, Daniel

    2009-11-15

    Polysulfone (PSf)/polyacrylic acid ultrafiltration (PSf/PAA) membranes were prepared from a polymer blend in dimethylformamide by coagulation in water according to the wet phase inversion method. Immobilization of water-soluble PAA within the non-soluble PSf matrix was proven by the increase of ion exchange capacity and the intensity of the carboxyl groups' peak with the increase of PAA content as shown by Fourier transform infrared spectra. These results lead to consider that PSf and PAA form a semi-interpenetrating polymer networks. The obtained membranes showed a decrease of mean surface-pore sizes, the overall porosity and the hydraulic permeability with the increase in PAA content. Such results were imputed to the morphologic modifications of PSf film with the immobilization of increasing PAA amount. PSf/PAA membranes showed high lead, cadmium and chromium rejection which reaches 100% at pH superior to 5.7 and a low rejection at low pH. Moreover, the heavy metal rejection decreases with feed solution concentration and applied pressure increases. These behaviors were attributed to the role of carboxylic groups in ion exchange or complexation. As a matter of fact, the strong lead ion-PAA interactions were revealed by the scanning electron microscopy with energy dispersive X-rays (SEM-EDX).

  5. An innovative treatment concept for future drinking water production: fluidized ion exchange – ultrafiltration – nanofiltration – granular activated carbon filtration

    Directory of Open Access Journals (Sweden)

    J. C. van Dijk

    2009-08-01

    Full Text Available A new treatment concept for drinking water production from surface water has been investigated on a pilot scale. The treatment concept consists of fluidized ion exchange (FIEX, ultrafiltration (UF, nanofiltration (NF, and granular activated carbon filtration (GAC. The FIEX process removed calcium and other divalent cations; the UF membrane removed particles and micro-organisms; and the NF membrane and GAC removed natural organic matter (NOM and micro-pollutants. This study focused on the prevention of fouling of the UF and scaling of the NF and investigated the overall removal of micro-pollutants by the treatment concept. The results of the experiments showed that in 14 days of continuous operation at a flux of 65 l/h m2 the UF performance was stable with the FIEX pre-treated feed water without the aid of a coagulant. The scaling of the NF was also not observed even at 97% recovery. Different micro-pollutants were spiked in the NF feed water and their concentrations in the effluent of NF and GAC were measured. The combination of NF and GAC removed most of the micro-pollutants successfully, except for the very polar substances with a molecular weight lower than 100 Daltons.

  6. Highly efficient forward osmosis based on porous membranes--applications and implications.

    Science.gov (United States)

    Qi, Saren; Li, Ye; Zhao, Yang; Li, Weiyi; Tang, Chuyang Y

    2015-04-07

    For the first time, forward osmosis (FO) was performed using a porous membrane with an ultrafiltration (UF)-like rejection layer and its feasibility for high performance FO filtration was demonstrated. Compared to traditional FO membranes with dense rejection layers, the UF-like FO membrane was 2 orders of magnitude more permeable. This gave rise to respectable FO water flux even at ultralow osmotic driving force, for example, 7.6 L/m(2).h at an osmotic pressure of merely 0.11 bar (achieved by using a 0.1% poly(sodium 4-styrene-sulfonate) draw solution). The membrane was applied to oil/water separation, and a highly stable FO water flux was achieved. The adoption of porous FO membranes opens a door to many new opportunities, with potential applications ranging from wastewater treatment, valuable product recovery, and biomedical applications. The potential applications and implications of porous FO membranes are addressed in this paper.

  7. Influence of floc size and structure on membrane fouling in coagulation-ultrafiltration hybrid process-The role of Al{sub 13} species

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Weiying [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Ji' nan 250100, Shandong (China); Gao, Baoyu, E-mail: baoyugao_sdu@yahoo.com.cn [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Ji' nan 250100, Shandong (China); Mao, Ranran; Yue, Qinyan [Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Ji' nan 250100, Shandong (China)

    2011-10-15

    Highlights: {yields} The optimum dose of Al{sub 13} for improving the membrane permeability was 5 mg/L and for PACl was 7 mg/L. {yields} Effluent coagulated by Al{sub 13} species presented lower proportion of R{sub a} in the total resistance due to the high strength of Al{sub 13}-HA flocs. {yields} The high D{sub f} of flocs formed by Al{sub 13} was not favorable for the reduction of cake layer resistance. - Abstract: Coagulation application prior to ultrafiltration process was carried out to increase humic acid (HA) removal and membrane permeability. The [Al{sub 13}O{sub 4}(OH){sub 24}(H{sub 2}O){sub 12}]{sup 7+} polycation (Al{sub 13} species) was used in the coagulant process and polyaluminum chloride (PACl) was also used for comparison. Characteristics of aggregates pre-coagulated by Al{sub 13} species and PACl were investigated using a laser diffraction particle sizing device. Additionally, membrane fouling was investigated under different coagulation conditions. The various resistances caused by Al{sub 13} and PACl treatment effluents were determined using the membrane fouling index equation. The results indicated that at dose of 1 and 3 mg/L, Al{sub 13} produced larger flocs than PACl; while when dosage further increased, the PACl-HA flocs were much larger. The flocs formed by Al{sub 13} were strong and compact, and those formed by PACl were weak and loosely structured with the exception of the flocs generated at 1 mg/L. The investigation of membrane fouling demonstrated that Al{sub 13} contributed to the best effluent permeating at 5 mg/L and the corresponding dose for PACl was 7 mg/L. The adsorption resistance of effluent pre-treated by Al{sub 13} accounted for a smaller percentage of the total resistances compared with that by PACl.

  8. Ceramic membrane fouling during ultrafiltration of oil/water emulsions: Roles played by stabilization surfactants of oil droplets

    KAUST Repository

    Lu, Dongwei; Zhang, Tao; Ma, Jun

    2015-01-01

    of classical fouling models, and analysis of organic components rejected by the membrane. Furthermore, this mechanism was also verified by the existence of a steric effect and demulsification effect. Our finding suggests that ceramic membrane oppositely charged

  9. Ultrafiltration of thin stillage from conventional and e-mill dry grind processes.

    Science.gov (United States)

    Arora, Amit; Dien, Bruce S; Belyea, Ronald L; Wang, Ping; Singh, Vijay; Tumbleson, M E; Rausch, Kent D

    2011-05-01

    We used ultrafiltration (UF) to evaluate membrane filtration characteristics of thin stillage and determine solids and nutrient compositions of filtered streams. To obtain thin stillage, corn was fermented using laboratory methods. UF experiments were conducted in batch mode under constant temperature and flow rate conditions. Two regenerated cellulose membranes (10 and 100 kDa molecular weight cutoffs) were evaluated with the objective of retaining solids as well as maximizing permeate flux. Optimum pressures for 10 and 100 kDa membranes were 207 and 69 kPa, respectively. Total solids, ash, and neutral detergent fiber contents of input TS streams of dry grind and E-Mill processes were similar; however, fat and protein contents were different (p stillage fractionation had higher mean total solids contents (27.6% to 27.8%) compared to E-Mill (22.2% to 23.4%). Total solids in retentate streams were found similar to those from commercial evaporators used in industry (25% to 35% total solids). Fat contents of retentate streams ranged from 16.3% to 17.5% for the conventional process. A 2% increment in fat concentration was observed in the E-Mill retentate stream. Thin stillage ash content was reduced 60% in retentate streams.

  10. Development of ultrafiltration and inorganic adsorbents for reducing volumes of low-level and intermediate-level liquid waste: July--September 1977

    International Nuclear Information System (INIS)

    Koenst, J.W.; Herald, W.R.; Roberts, R.C.

    1978-01-01

    The ultrafiltration (UF) pilot system is being evaluated at Mound Facility. The effect of pressure drop, temperature, and pH of the feed on system performance has been studied. The system has been run through a number of cleaning cycles including tap water flush, enzyme soak, detergent wash, and citric acid/oxalic acid wash. A continuous run was started on waste from the Waste Processing Facility; about 11,500 gal has been processed. Studies to determine the effect of (α, β, and γ) radiation on membrane characteristics were initiated. The small laboratory column tests were completed. Isotherms were run on several inorganic adsorbents, including titanium phosphate and sodium titanate. Tests were continued on the Engineering Test Ion Exchange System. Waste solution from the Waste Processing Facility spiked with plutonium-238 and ultrafiltration product spiked with uranium-233 were used as feeds. 6 tables, 1 figure

  11. Isoporous PS-b-PEO ultrafiltration membranes via self-assembly and water-induced phase separation

    KAUST Repository

    Karunakaran, Madhavan

    2014-03-01

    A simple and efficient approach towards the fabrication of a skinned membrane with highly ordered pores in the nanometer range is presented here. We successfully combined the self-assembly of PS-b-PEO block copolymer and water induced phase separation for the preparation of isoporous PS-b-PEO block copolymer membranes. We produced for the first time asymmetric isoporous PS-b-PEO membranes with a 100nm thin isoporous separating layer using water at room temperature as coagulant. This was possible by careful selection of the block lengths and the solvent system. FESEM, AFM and TEM measurements were employed to characterize the nanopores of membranes. The pure water fluxes were measured and the flux of membrane was exceptionally high (around 800Lm-2h-1bar-1). Protein rejection measurements were carried out for this membrane and the membrane had a retention of about 67% of BSA and 99% of γ-globulin. © 2013 Elsevier B.V.

  12. Ceramic membrane development in NGK

    Energy Technology Data Exchange (ETDEWEB)

    Araki, Kiyoshi; Sakai, Hitoshi, E-mail: kinsakai@ngk.co.jp [Corporate R and D, NGK Insulators, Ltd., Nagoya 467-8530 (Japan)

    2011-05-15

    NGK Insulators, Ltd. was established in 1919 to manufacture the electric porcelain insulators for power transmission lines. Since then, our business has grown as one of the world-leading ceramics manufacturing companies and currently supply with the various environmentally-benign ceramic products to worldwide. In this paper, ceramic membrane development in NGK is described in detail. We have been selling ceramic microfiltration (MF) membranes and ultra-filtration (UF) membranes for many years to be used for solid/liquid separation in various fields such as pharmaceutical, chemical, food and semiconductor industries. In Corporate R and D, new ceramic membranes with sub-nanometer sized pores, which are fabricated on top of the membrane filters as support, are under development for gas and liquid/liquid separation processes.

  13. Ceramic membrane development in NGK

    Science.gov (United States)

    Araki, Kiyoshi; Sakai, Hitoshi

    2011-05-01

    NGK Insulators, Ltd. was established in 1919 to manufacture the electric porcelain insulators for power transmission lines. Since then, our business has grown as one of the world-leading ceramics manufacturing companies and currently supply with the various environmentally-benign ceramic products to worldwide. In this paper, ceramic membrane development in NGK is described in detail. We have been selling ceramic microfiltration (MF) membranes and ultra-filtration (UF) membranes for many years to be used for solid/liquid separation in various fields such as pharmaceutical, chemical, food and semiconductor industries. In Corporate R&D, new ceramic membranes with sub-nanometer sized pores, which are fabricated on top of the membrane filters as support, are under development for gas and liquid/liquid separation processes.

  14. In-line coagulation prior to UF of treated domestic wastewater - foulants removal, fouling control and phosphorus removal

    KAUST Repository

    Zheng, Xing; Plume, Stephan; Ernst, Mathias; Croue, Jean-Philippe; Jekel, Martin R.

    2012-01-01

    The present work investigated fouling control and phosphorus removal by applying in-line coagulation prior to ultrafiltration (UF) of treated domestic wastewater. Experiments were conducted in both lab- and pilot-scale under close to neutral pH condition. Lab-scale foulant removal tests showed that increasing the dosage of FeCl3, AlCl3 and polymeric aluminum chloride (PACl) can improve biopolymer removal. Specifically, PACl reduced preferentially the proteinaceous fraction of biopolymer while the other two coagulants showed no significant preference. The filterability of water samples was improved after coagulation, which is contributed to biopolymer removal and the formation of larger particles. Pilot UF experiments demonstrated that in-line coagulation improved the performance of UF to a large extent. Within 0.037-0.148mmol Me3+/L dosage range, adding more FeCl3 and AlCl3 slowed down the development of trans-membrane pressure (TMP) correspondingly, while changing PACl dosage showed little effect on the variation of TMP increase rate. Further investigations indicated that PACl related precipitates contributed to more irreversible fouling than that which the monomeric coagulants made. Fouling control is thus considered as a co-effect determined by foulant removal efficiency, fouling layer structure and the adherence of hydrolysis products/precipitates onto the membrane. With respect to phosphorus removal, dosing FeCl3 and AlCl3 achieved higher removal efficiency than using PACl. Based on lab- and pilot-scale results, dosing FeCl3 and AlCl3 at a relative dosage of over 2.5mol Me3+ per mol total phosphorus (TP) in feedwater is necessarily required to keep the TP concentration under 50μg/L in UF permeate. © 2012 Elsevier B.V.

  15. In-line coagulation prior to UF of treated domestic wastewater - foulants removal, fouling control and phosphorus removal

    KAUST Repository

    Zheng, Xing

    2012-06-01

    The present work investigated fouling control and phosphorus removal by applying in-line coagulation prior to ultrafiltration (UF) of treated domestic wastewater. Experiments were conducted in both lab- and pilot-scale under close to neutral pH condition. Lab-scale foulant removal tests showed that increasing the dosage of FeCl3, AlCl3 and polymeric aluminum chloride (PACl) can improve biopolymer removal. Specifically, PACl reduced preferentially the proteinaceous fraction of biopolymer while the other two coagulants showed no significant preference. The filterability of water samples was improved after coagulation, which is contributed to biopolymer removal and the formation of larger particles. Pilot UF experiments demonstrated that in-line coagulation improved the performance of UF to a large extent. Within 0.037-0.148mmol Me3+/L dosage range, adding more FeCl3 and AlCl3 slowed down the development of trans-membrane pressure (TMP) correspondingly, while changing PACl dosage showed little effect on the variation of TMP increase rate. Further investigations indicated that PACl related precipitates contributed to more irreversible fouling than that which the monomeric coagulants made. Fouling control is thus considered as a co-effect determined by foulant removal efficiency, fouling layer structure and the adherence of hydrolysis products/precipitates onto the membrane. With respect to phosphorus removal, dosing FeCl3 and AlCl3 achieved higher removal efficiency than using PACl. Based on lab- and pilot-scale results, dosing FeCl3 and AlCl3 at a relative dosage of over 2.5mol Me3+ per mol total phosphorus (TP) in feedwater is necessarily required to keep the TP concentration under 50μg/L in UF permeate. © 2012 Elsevier B.V.

  16. Preliminary Study on the Removal of Steroidal Estrogens Using TiO2-Doped PVDF Ultrafiltration Membranes

    Directory of Open Access Journals (Sweden)

    Mingquan Wang

    2016-04-01

    Full Text Available Steroidal estrogens are a representative type of endocrine-disrupting chemical contaminant that has been detected in surface water. In this paper, modified polyvinylidene fluoride (PVDF membranes were prepared by adding different amounts of polyvinyl pyrrolidone (PVP and nano-TiO2 particles. PVDF-PVP membrane adsorption, UV photolysis and PVDF-PVP-TiO2 membrane photocatalysis performance were investigated by considering the rejection of estrone (E1 and 17β-estradiol (E2 in the cross-flow filtration experiments. The mechanism of photocatalytic degradation on TiO2-doped PVDF membranes was also evaluated. The results from the study indicated that adding PVP and nano-TiO2 appropriately in PVDF membranes could be an effective method for better E1and E2 rejection due to adsorption and photocatalytic degradation.

  17. Membrane technology applications

    Energy Technology Data Exchange (ETDEWEB)

    Golomb, A

    1990-10-01

    Due to a continuing emphasis on increasing the efficiency of utilizing the Province's electrical energy system, a Membrane Testing and Development Facility (MTDF) has been established at Ontario Hydro Research Division. The MTDF comprises bench-scale and pilot-scale reverse osmosis (RO) and ultrafiltration (UF) systems. RO and UF are membrane separation technologies which with microfiltration (MF) have found numerous industrial applications in wastewater treatment and/or byproduct recovery. Since no phase change is involved in RO and UF, they are more energy efficient separation processes than, say, evaporation or distillation. Initial tests have been carried out to demonstrate the capability of the newly-established MTDF. Bench- and pilot-scale RO treatment, at 4.1 MPa applied pressure, of a simulated nickel plating waste rinse stream was demonstrated. RO membrane rejection efficiencies for nickel were 99+% (in the bench scale test) and 99.9+% (on the pilot scale). Volume reduction factors of about 25 were attained, at purified water flux rates in the range 1 to 1.5 m{sup 3}/m{sup 2} per day. Good correlation was noted between bench-scale and pilot-scale RO test results. Pilot-scale UF of a simulated industrial cutting oil/water waste emulsion at 0.40 MPa gave 99+% oil rejection (pilot scale) at a flux rate of 0.7 m{sup 3}/m{sup 2} per day. A volume reduction of about 5.2 was attained. Overviews of opportunities for membrane separation technology applied to the metal cutting and surface finishing industries, and the food and beverage industry are given. Capabilities (and some present needs) of the MTDF are outlined, with recommendations. 17 refs., 10 figs., 7 tabs.

  18. Optimized permeation and antifouling of PVDF hybrid ultrafiltration membranes: synergistic effect of dispersion and migration for fluorinated graphene oxide

    Science.gov (United States)

    Li, Mingming; Shi, Jie; Chen, Cheng; Li, Nan; Xu, Zhiwei; Li, Jing; Lv, Hanming; Qian, Xiaoming; Jiao, Xiaoning

    2017-03-01

    Nanoparticles may have suffered from low modification efficiency in hybrid membranes due to embedding and aggregating in polymer matrix. In order to analyze the modification mechanisms of nanoparticle migration and dispersion on the properties of hybrid membranes, we designed different F/ O ratios ( R F/ O ) of fluorinated graphene oxide (FGO, diameter = 1.5 17.5 μm) by carbon tetrafluoride (CF4) plasma treatment GO for 3, 5, 10, 15, and 20 min and successfully prepared novel PVDF hybrid membranes containing FGO via the phase inversion method. After a prolonged plasma treatment, the R F/ O of FGO was enhanced sharply, indicating an increasing compatibility of FGO with the matrix, especially FGO-20 (GO treated for 20 min). FGO contents in the top layer, sublayer, and the whole of membranes were probed by X-ray photoelectron spectroscopy, energy-dispersive spectrometer, and indirect computation, respectively. In the top layer of membranes, FGO contents declined from 13.14 wt% (PVDF/GO) to 4.00 wt% (PVDF/FGO-10) and 1.96 wt% (PVDF/FGO-20) due to the reduced migration ability of FGO. It is worth mentioning that PVDF/FGO-10 membranes exhibited an excellent water flux and flux recovery rate (up to 406.90 L m-2 h-1 and 88.9%), which were improved by 67.3% and 14.6% and 52.5% and 24.0% compared with those of PVDF/GO and PVDF/FGO-20 membranes, respectively, although the dispersion and migration ability of FGO-10 was maintained at a moderate level. It indicated that the migration and dispersion of FGO in membranes could result in dynamic equilibrium, which played a key role in making the best use of nanomaterials to optimize membrane performance.

  19. Membrane processes for the treatment of exhausted effluents from leather industry; Processi a membrana per il trattamento degli effluenti esausti dell'industria conciaria

    Energy Technology Data Exchange (ETDEWEB)

    Cassano, A.; Molinari, R.; Drioli, E. [Arcavata di Rende Univ. della Calabria, Arcavata di Rende, CS (Italy). Istituto di Ricerca su Membrane e Modellistica di Reattori Chimici

    2001-03-01

    This paper considers the potentiality of some membrane processes such as ultrafiltration (UF), nano filtration (NF) and reverse osmosis (RO), in the treatment of exhausted effluents produced by the tanning cycle, based on the experimental results of the Research Group. [Italian] In questo studio vengono analizzate le potenzialita' applicative di alcuni processi a membrana, quali ultrafiltrazione (UF), nanofiltrazione (NF) e osmosi inversa (Ol), nel trattamento degli effluenti esausti del ciclo conciario, sulla base di risultati sperimentali del gruppo di ricerca del Cnr-Irmerc.

  20. Evaluating the efficiency of different microfiltration and ultrafiltration membranes used as pretreatment for Red Sea water reverse osmosis desalination

    KAUST Repository

    Almashharawi, Samir; Ghaffour, NorEddine; Al-Ghamdi, M.; Amy, Gary L.

    2013-01-01

    consistent silt density index, coagulation control at low total suspended solids, and management of higher waste sludge. Recently, there has been a rapid growth in the use of low-pressure membranes as pretreatment for RO systems replacing the conventional

  1. Surprising transformation of a block copolymer into a high performance polystyrene ultrafiltration membrane with a hierarchically organized pore structure

    KAUST Repository

    Shevate, Rahul

    2018-02-08

    We describe the preparation of hierarchical polystyrene nanoporous membranes with a very narrow pore size distribution and an extremely high porosity. The nanoporous structure is formed as a result of unusual degradation of the poly(4-vinyl pyridine) block from self-assembled poly(styrene)-b-poly(4-vinyl pyridine) (PS-b-P4VP) membranes through the formation of an unstable pyridinium intermediate in an alkaline medium. During this process, the confined swelling and controlled degradation produced a tunable pore size. We unequivocally confirmed the successful elimination of the P4VP block from a PS-b-P4VPVP membrane using 1D/2D NMR spectroscopy and other characterization techniques. Surprisingly, the long range ordered surface porosity was preserved even after degradation of the P4VP block from the main chain of the diblock copolymer, as revealed by SEM. Aside from a drastically improved water flux (∼67% increase) compared to the PS-b-P4VP membrane, the hydraulic permeability measurements validated pH independent behaviour of the isoporous PS membrane over a wide pH range from 3 to 10. The effect of the pore size on protein transport rate and selectivity (a) was investigated for lysozyme (Lys), bovine serum albumin (BSA) and globulin-γ (IgG). A high selectivity of 42 (Lys/IgG) and 30 (BSA/IgG) was attained, making the membranes attractive for size selective separation of biomolecules from their synthetic model mixture solutions.

  2. Evaluation of the MF/UF Performance for the Reuse of Sand Filter Backwash Water from Drinking Water Treatment Plants

    Directory of Open Access Journals (Sweden)

    Neda Shirzadi

    2015-05-01

    Full Text Available The aim of this study was to investigate the application of micro-filtration and ultra-filtration membrane systems in order to improve the physical and microbial quality and the reuse of backwash water from the sand filter units in water treatment plants. The backwash water from filters makes up for 3 to 5 percent of the total water treated, which is disposed in most WTPs. However, the treatment and reuse of the backwash water is more admissible from technical and economic viewpoints, especially in view of the present water scarcity. For the purposes of this study, use was made of membrane modules of micro- and ultra-filters on a pilot scale. The micro-filter employed consisted of a polypropylene membrane module with a porosity of 1 micron in size and a fiberglass module with a porosity of 5 microns. The ultra-filter was made of PVC hollow fiber with a molecular weight of 100,000 Dalton. In order to feed the two pilots, backwash water from a sand filter was collected from one of the WTPs in Tehran. After samples were taken from the backwash water, the physical and microbial removal efficiency was periodically evaluated based on the standard method and the micro-filtration, ultra-filtration, and combined MF/UF processes were compared with respect to their performance. The results indicate that the combined MF/UF process is able to decrease turbidity, MPN, COD, TSS, and Fe with efficiency values of 99.9, 100, 61.5, 99.9 and 98.8 percent, respectively. Overall, the findings confirmed the technical capabilities of this method for the recovery and reuse of the effluent produced in the backwashing mechanism of sand filters in WTPs.

  3. Enhancement of glucose uptake in muscular cell by soybean charged peptides isolated by electrodialysis with ultrafiltration membranes (EDUF): activation of the AMPK pathway.

    Science.gov (United States)

    Roblet, Cyril; Doyen, Alain; Amiot, Jean; Pilon, Geneviève; Marette, André; Bazinet, Laurent

    2014-03-15

    Soy peptides consumption has been associated with beneficial effects in type 2 diabetes patients. However, the peptide fractions responsible for these effects, and their mechanisms of action, have not been identified yet. In this study, we have isolated soybean peptides by electrodialysis with an ultrafiltration membrane (EDUF) at 50 V/100 kDa, and tested them for their capacity to improve glucose uptake in L6 muscle cells. We observed that these fractions were able to significantly enhance glucose uptake in the presence of insulin. The reported bioactivity would be due to the low molecular weight peptides (300-500 Da) recovered. Moreover, we observed that an enhancement of glucose uptake was correlated to the activation of the AMPK enzyme, well known for its capacity to increase glucose uptake in muscle cells. To our knowledge, this is the first time that bioactive peptides with glucose uptake activity have been isolated from a complex soy matrix, and that the implication of AMPK in it is demonstrated. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Hybrid coagulation-UF processes for spent filter backwash water treatment: a comparison studies for PAFCl and FeCl3 as a pre-treatment.

    Science.gov (United States)

    Ebrahimi, Afshin; Amin, Mohammad Mehdi; Pourzamani, Hamidreza; Hajizadeh, Yaghoub; Mahvi, Amir Hossein; Mahdavi, Mokhtar; Rad, Mohammad Hassan Rabie

    2017-08-01

    In this study, the reclamation of clean water from spent filter backwash water (SFBW) was investigated through pilot-scale experiments. The pilot plant consisted of pre-sedimentation, coagulation, flocculation, clarification, and ultrafiltration (UF). Two coagulants of PAFCl and FeCl 3 were investigated with respect to their performance on treated SFBW quality and UF membrane fouling. At the optimum dose of PAFCl and FeCl 3 turbidity removal of 99.6 and 99.4% was attained, respectively. PAFCl resulted in an optimum UV 254 , TOC, and DOC removal of 80, 83.6, and 72.7%, respectively, and FeCl 3 caused the removal of those parameters by 76.7, 80.9, and 65.9%, respectively. PAFCl removed hydrophilic and transphilic constituent better than FeCl 3 , but FeCl 3 had, to some extent, higher affinities to a hydrophobic fraction. It was concluded that PAFCl showed a better coagulation performance in most cases and caused a lower membrane fouling rate compared to FeCl 3 . Finally, the treated SFBW with both coagulant-UF systems met the drinking water standards.

  5. Optimized permeation and antifouling of PVDF hybrid ultrafiltration membranes: synergistic effect of dispersion and migration for fluorinated graphene oxide

    Energy Technology Data Exchange (ETDEWEB)

    Li, Mingming; Shi, Jie; Chen, Cheng; Li, Nan; Xu, Zhiwei, E-mail: xuzhiwei@tjpu.edu.cn; Li, Jing; Lv, Hanming; Qian, Xiaoming, E-mail: qianxiaoming@tjpu.edu.cn; Jiao, Xiaoning [Tianjin Polytechnic University, State Key Laboratory of Separation Membranes and Membrane Processes, School of Textiles (China)

    2017-03-15

    Nanoparticles may have suffered from low modification efficiency in hybrid membranes due to embedding and aggregating in polymer matrix. In order to analyze the modification mechanisms of nanoparticle migration and dispersion on the properties of hybrid membranes, we designed different F/O ratios (R{sub F/O}) of fluorinated graphene oxide (FGO, diameter = 1.5 ~ 17.5 μm) by carbon tetrafluoride (CF{sub 4}) plasma treatment GO for 3, 5, 10, 15, and 20 min and successfully prepared novel PVDF hybrid membranes containing FGO via the phase inversion method. After a prolonged plasma treatment, the R{sub F/O} of FGO was enhanced sharply, indicating an increasing compatibility of FGO with the matrix, especially FGO-20 (GO treated for 20 min). FGO contents in the top layer, sublayer, and the whole of membranes were probed by X-ray photoelectron spectroscopy, energy-dispersive spectrometer, and indirect computation, respectively. In the top layer of membranes, FGO contents declined from 13.14 wt% (PVDF/GO) to 4.00 wt% (PVDF/FGO-10) and 1.96 wt% (PVDF/FGO-20) due to the reduced migration ability of FGO. It is worth mentioning that PVDF/FGO-10 membranes exhibited an excellent water flux and flux recovery rate (up to 406.90 L m{sup −2} h{sup −1} and 88.9%), which were improved by 67.3% and 14.6% and 52.5% and 24.0% compared with those of PVDF/GO and PVDF/FGO-20 membranes, respectively, although the dispersion and migration ability of FGO-10 was maintained at a moderate level. It indicated that the migration and dispersion of FGO in membranes could result in dynamic equilibrium, which played a key role in making the best use of nanomaterials to optimize membrane performance.

  6. Optimization of O3 as Pre-Treatment and Chemical Enhanced Backwashing in UF and MF Ceramic Membranes for the Treatment of Secondary Wastewater Effluent and Red Sea Water

    KAUST Repository

    Herrera, Catalina

    2011-12-12

    Ceramic membranes have proven to have many advantages over polymeric membranes. Some of these advantages are: resistance against extreme pH, higher permeate flux, less frequent chemical cleaning, excellent backwash efficiency and longer lifetime. Other main advantage is the use of strong chemical agent such as Ozone (O3), to perform membrane cleaning. Ozone has proven to be a good disinfection agent, deactivating bacteria and viruses. Ozone has high oxidation potential and high reactivity with natural organic matter (NOM). Several studies have shown that combining ozone to MF/UF systems could minimize membrane fouling and getting higher operational fluxes. This work focused on ozone – ceramic membrane filtration for treating wastewater effluent and seawater. Effects of ozone as a pre – treatment or chemical cleaning with ceramic membrane filtration were identified in terms of permeate flux and organic fouling. Ozonation tests were done by adjusting O3 dose with source water, monitoring flux decline and membrane fouling. Backwashing availability and membrane recovery rate were also analyzed. Two types of MF/UF ceramics membranes (AAO and TAMI) were used for this study. When ozone dosage was higher in the source water, membrane filtration improved in performance, resulting in a reduced flux decline. In secondary wastewater effluent, raw source water declined up to 77% of normalized flux, while with O3 as pre – treatment, source water at its higher O3 dose, flux decreased only 33% of normalized flux. For seawater, membrane performance increase from declining to 37% of its final normalized flux to 21%, when O3 as a pre – treatment was used. Membrane recovery rate also improved even with low O3 dose, as an example, with 8 mg/L irreversible fouling decreases from 58% with no ozone addition to 29% for secondary wastewater effluent treatment. For seawater treatment, irreversible fouling decreased from 37% with no ozone addition to 21% at 8 mg/L, proving ozone is a

  7. UV/H2O2 process performance improvement by ultrafiltration and physicochemical clarification systems for industrial effluent pretreatment

    Directory of Open Access Journals (Sweden)

    Ivanildo Hespanhol

    2012-12-01

    Full Text Available The present study evaluated the removal of TOC from an effluent with high organic load resulted from the treatment of oil-water emulsion by thermal process. Hollow Fiber Ultrafiltration membrane (HF-UF and physicochemical clarification process were used as pretreatment options to assess the influence of feed effluent quality on the UV/H2O2 oxidation process. Results for TOC removals showed HF-UF and physicochemical clarification processes can significantly improve the efficiency of UV/H2O2 oxidation process, when compared with the direct effluent oxidation. Reaction time for obtaining a TOC removal higher than 90% was reduced to approximately half of the time needed when no pretreatment was applied. Considering both pretreatment processes it was not possible to notice any significant difference on the UV/H2O2 oxidation process performance. However, the complexity of physicochemical process due to the use of three different chemicals and sludge production made the HF-UF process the best pretreatment alternative, without increasing the Total Dissolved Solids of the effluent, a very important issue when water reuse is considered.

  8. Isoporous PS-b-PEO ultrafiltration membranes via self-assembly and water-induced phase separation

    KAUST Repository

    Karunakaran, Madhavan; Nunes, Suzana Pereira; Qiu, Xiaoyan; Yu, Haizhou; Peinemann, Klaus-Viktor

    2014-01-01

    A simple and efficient approach towards the fabrication of a skinned membrane with highly ordered pores in the nanometer range is presented here. We successfully combined the self-assembly of PS-b-PEO block copolymer and water induced phase

  9. Surprising transformation of a block copolymer into a high performance polystyrene ultrafiltration membrane with a hierarchically organized pore structure

    KAUST Repository

    Shevate, Rahul; Kumar, Mahendra; Karunakaran, Madhavan; Canlas, Christian; Peinemann, Klaus-Viktor

    2018-01-01

    ) block from self-assembled poly(styrene)-b-poly(4-vinyl pyridine) (PS-b-P4VP) membranes through the formation of an unstable pyridinium intermediate in an alkaline medium. During this process, the confined swelling and controlled degradation produced a

  10. More Efficient Sodium Removal by Ultrafiltration Compared to Diuretics in Acute Heart Failure; Underexplored and Overstated.

    Science.gov (United States)

    Kazory, Amir

    2016-01-01

    Enhanced removal of sodium has often been cited as an advantage of ultrafiltration (UF) therapy over diuretic-based medical treatment in the management of acute decompensated heart failure. However, so far clinical studies have rarely evaluated the precise magnitude of sodium removal, and this assumption is largely based on the physiologic mechanisms and anecdotal observations that predate the contemporary management of heart failure. Recent data suggest that patients treated with UF experience substantial reduction in urinary sodium excretion possibly due to prolonged intravascular volume contraction. Consequently, the efficient sodium extraction through production of isotonic ultrafiltrate can be offset by urine hypotonicity. Based on the limited currently available data, it seems unlikely that the persistent benefits of UF could be solely explained by its greater efficiency in sodium removal. The design of the future studies should include frequent measurements of urine sodium to precisely compare the impact of UF and diuretics on sodium balance. © 2016 S. Karger AG, Basel.

  11. Preliminary studies on membrane filtration for the production of potable water: a case of Tshaanda rural village in South Africa.

    Science.gov (United States)

    Molelekwa, Gomotsegang F; Mukhola, Murembiwa S; Van der Bruggen, Bart; Luis, Patricia

    2014-01-01

    Ultrafiltration (UF) systems have been used globally for treating water from resources including rivers, reservoirs, and lakes for the production of potable water in the past decade. UF membranes with a pore size of between 0.1 and 0.01 micrometres provide an effective barrier for bacteria, viruses, suspended particles, and colloids. The use of UF membrane technology in treating groundwater for the supply of potable water in the impoverished and rural village, Tshaanda (i.e., the study area) is demonstrated. The technical and administrative processes that are critical for the successful installation of the pilot plant were developed. Given the rural nature of Tshaanda, the cultural and traditional protocols were observed. Preliminary results of the water quality of untreated water and the permeate are presented. Escherichia coli in the untreated water during the dry season (i.e., June and July) was 2 cfu/100 ml and was 2419.2 cfu/100 ml) before UF. Following UF, it dramatically reduced to acceptable level (7 cfu/100 ml) which is within the WHO recommended level of water for suspended particles and colloids. Considering these data, it can be concluded that the water is suitable for human consumption, following UF.

  12. Preliminary studies on membrane filtration for the production of potable water: a case of Tshaanda rural village in South Africa.

    Directory of Open Access Journals (Sweden)

    Gomotsegang F Molelekwa

    Full Text Available Ultrafiltration (UF systems have been used globally for treating water from resources including rivers, reservoirs, and lakes for the production of potable water in the past decade. UF membranes with a pore size of between 0.1 and 0.01 micrometres provide an effective barrier for bacteria, viruses, suspended particles, and colloids. The use of UF membrane technology in treating groundwater for the supply of potable water in the impoverished and rural village, Tshaanda (i.e., the study area is demonstrated. The technical and administrative processes that are critical for the successful installation of the pilot plant were developed. Given the rural nature of Tshaanda, the cultural and traditional protocols were observed. Preliminary results of the water quality of untreated water and the permeate are presented. Escherichia coli in the untreated water during the dry season (i.e., June and July was 2 cfu/100 ml and was 2419.2 cfu/100 ml before UF. Following UF, it dramatically reduced to acceptable level (7 cfu/100 ml which is within the WHO recommended level of <10 cfu/100 ml. Additionally, during the wet/rainy season E. coli and enterococci were unacceptably high (40.4 cfu/100 ml and 73.3 cfu/100 ml, respectively before UF but were completely removed following UF, which are within the WHO and SANS recommended limit. The values for electrical conductivity (EC and turbidity were constantly within the WHO recommended limits of 300 µS/cm corrected at 25°C and <5 NTU, respectively, before and after UF, during dry season and wet season. This suggests that there is no need for pre-treatment of the water for suspended particles and colloids. Considering these data, it can be concluded that the water is suitable for human consumption, following UF.

  13. MEMBRANE BIOREACTOR FOR TREATMENT OF RECALCITRANT WASTEWATERS

    Directory of Open Access Journals (Sweden)

    Suprihatin Suprihatin

    2012-02-01

    Full Text Available The low biodegradable wastewaters remain a challenge in wastewater treatment technology. The performance of membrane bioreactor systems with submerged hollow fiber micro- and ultrafiltration membrane modules were examined for purifying recalcitrant wastewaters of leachate of a municipal solid waste open dumping site and effluent of pulp and paper mill. The use of MF and UF membrane bioreactor systems showed an efficient treatment for both types wastewaters with COD reduction of 80-90%. The membrane process achieved the desirable effects of maintaining reasonably high biomass concentration and long sludge retention time, while producing a colloid or particle free effluent. For pulp and paper mill effluent a specific sludge production of 0.11 kg MLSS/kg COD removed was achieved. A permeate flux of about 5 L/m²h could be achieved with the submerged microfiltration membrane. Experiments using ultrafiltration membrane produced relatively low permeate fluxes of 2 L/m²h. By applying periodical backwash, the flux could be improved significantly. It was indicated that the particle or colloid deposition on membrane surface was suppressed by backwash, but reformation of deposit was not effectively be prevented by shear-rate effect of aeration. Particle and colloid started to accumulate soon after backwash. Construction of membrane module and operation mode played a critical role in achieving the effectiveness of aeration in minimizing deposit formation on the membrane surface.

  14. Removal of residual palm oil-based biodiesel catalyst using membrane ultra-filtration technique: An optimization study

    Directory of Open Access Journals (Sweden)

    I.M. Atadashi

    2014-09-01

    Full Text Available In this research work, residual potassium hydroxide catalyst was removed from palm oil-based alkyl esters (biodiesel using membrane separative technique, with the aim of achieving high-quality biodiesel that meets international standard specifications. Further, Central Composite Design (CCD coupled with Response Surface Methodology (RSM was employed to study the effects of the system variables such as flow rate, temperature and transmembrane pressure (TMP on the retention of potassium. At the optimum conditions, the coefficient of retention (%R of the catalyst was 93.642, and the content of the potassium was reduced from 8.328 mg/L to 0.312 mg/L; a value well below the one specified by both EN 14214 and ASTM D6751 standards. In addition, the comparison between predicted and experimental values for the catalyst retention offers a reasonable percentage error of 0.081%. Therefore, this study has proven that membrane technique can be used to post treat crude biodiesel; in order to achieve high-quality biodiesel fuel that can be efficiently used on diesel engines.

  15. An enquiry on appropriate selection of polymers for preparation of polymeric nanosorbents and nanofiltration/ultrafiltration membranes for hormone micropollutants removal from water effluents.

    Science.gov (United States)

    Khansary, Milad Asgarpour; Mellat, Mostafa; Saadat, Seyed Hassan; Fasihi-Ramandi, Mahdi; Kamali, Mehdi; Taheri, Ramezan Ali

    2017-02-01

    To analyze polymeric nanosorbents and nanofiltration/ultrafiltration membranes for hormone micropollutants removal from water effluents, here an in-through investigation on the suitability and compatibility of various polymers has been carried out. For this work, estradiol, estrone, testosterone, progesterone, estriol, mestranol, and ethinylestradiol were considered. A total number of 452 polymers were analyzed and initially screened using Hansen solubility parameters. The identified good pairs of hormones and polymers then were examined to obtain the equilibrium capacity of hormones removal from water effluents using a modified Flory-Huggins model. A distribution coefficient was defined as the ratio of hormones in water effluent phase and polymer phase. For removal of mestranol, estradiol and ethinylestradiol, no compatible polymer was identified based on initial screening of collected database. Three compatible polymers were identified for estriol. For progesterone, a wide variety of polymers was identified as good matching of polar, dispersion and hydrogen forces contributions can be observed for these pairs. For estrone, only two polymers can be proposed due to the mismatch observed between polar, dispersion and hydrogen forces contributions of other polymers and this hormone. The phase calculations showed that not all the identified good pairs could be used for practical separation applications. The domain of applicability of each good pair was investigated and potential polymers for practical micropollutants removal together with their removal capacity were represented in terms of phase envelops. The theoretical approach follows fundamental chemical thermodynamic equations and then can be simply applied for any system of interest. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Fouling in Membrane Distillation, Osmotic Distillation and Osmotic Membrane Distillation

    Directory of Open Access Journals (Sweden)

    Mourad Laqbaqbi

    2017-03-01

    Full Text Available Various membrane separation processes are being used for seawater desalination and treatment of wastewaters in order to deal with the worldwide water shortage problem. Different types of membranes of distinct morphologies, structures and physico-chemical characteristics are employed. Among the considered membrane technologies, membrane distillation (MD, osmotic distillation (OD and osmotic membrane distillation (OMD use porous and hydrophobic membranes for production of distilled water and/or concentration of wastewaters for recovery and recycling of valuable compounds. However, the efficiency of these technologies is hampered by fouling phenomena. This refers to the accumulation of organic/inorganic deposits including biological matter on the membrane surface and/or in the membrane pores. Fouling in MD, OD and OMD differs from that observed in electric and pressure-driven membrane processes such electrodialysis (ED, membrane capacitive deionization (MCD, reverse osmosis (RO, nanofiltration (NF, ultrafiltration (UF, microfiltration (MF, etc. Other than pore blockage, fouling in MD, OD and OMD increases the risk of membrane pores wetting and reduces therefore the quantity and quality of the produced water or the concentration efficiency of the process. This review deals with the observed fouling phenomena in MD, OD and OMD. It highlights different detected fouling types (organic fouling, inorganic fouling and biofouling, fouling characterization techniques as well as various methods of fouling reduction including pretreatment, membrane modification, membrane cleaning and antiscalants application.

  17. Influence of gas-liquid two-phase flow on angiotensin-I converting enzyme inhibitory peptides separation by ultra-filtration.

    Science.gov (United States)

    Charoenphun, Narin; Youravong, Wirote

    2017-01-01

    Membrane fouling is a major problem in ultra-filtration systems and two-phase flow is a promising technique for permeate flux enhancement. The objective of this research was to study the use of an ultra-filtration (UF) system to enrich angiotensin-I converting enzyme (ACE) inhibitory peptides from tilapia protein hydrolysate. To select the most appropriate membrane and operating condition, the effects of membrane molecular weight cut-off (MWCO), transmembrane pressure (TMP) and cross-flow velocity (CFV) on permeate flux and ACE inhibitory peptide separation were studied. Additionally, the gas-liquid two-phase flow technique was applied to investigate its effect on the process capability. The results showed that the highest ACE inhibitory activity was obtained from permeate of the 1 kDa membrane. In terms of TMP and CFV, the permeate flux tended to increase with TMP and CFV. The use of gas-liquid two-phase flow as indicated by shear stress number could reduce membrane fouling and increase the permeate flux up to 42%, depending on shear stress number. Moreover, the use of a shear stress number of 0.039 led to an augmentation in ACE inhibitory activity of permeates. Operating conditions using a shear stress number of 0.039 were recommended for enrichment of ACE inhibitory peptides. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  18. Ultrafiltration of hemicellulose hydrolysate fermentation broth

    Science.gov (United States)

    Kresnowati, M. T. A. P.; Desiriani, Ria; Wenten, I. G.

    2017-03-01

    Hemicelulosic material is often used as the main substrate to obtain high-value products such as xylose. The five carbon sugar, xylose, could be further processed by fermentation to produce xylitol. However, not only the hemicellulose hydrolysate fermentation broth contains xylitol, but also metabolite products, residual substances, biomass and mineral salts. Therefore, in order to obtain the end products, various separation processes are required to separate and purify the desired product from the fermentation broth. One of the most promising downstream processing methods of fermentation broth clarification is ultrafiltration due to its potential for energy saving and higher purity. In addition, ultrafiltration membrane has a high performance in separating inhibitory components in the fermentation broth. This paper assesses the influence of operating conditions; including trans-membrane pressure, velocity, pH of the fermentation broth solutions, and also to the xylitol concentration in the product. The challenges of the ultrafiltration process will be pointed out.

  19. Reexamining ultrafiltration and solute transport in groundwater

    Science.gov (United States)

    Neuzil, C. E.; Person, Mark

    2017-06-01

    Geologic ultrafiltration—slowing of solutes with respect to flowing groundwater—poses a conundrum: it is consistently observed experimentally in clay-rich lithologies, but has been difficult to identify in subsurface data. Resolving this could be important for clarifying clay and shale transport properties at large scales as well as interpreting solute and isotope patterns for applications ranging from nuclear waste repository siting to understanding fluid transport in tectonically active environments. Simulations of one-dimensional NaCl transport across ultrafiltering clay membrane strata constrained by emerging data on geologic membrane properties showed different ultrafiltration effects than have often been envisioned. In relatively high-permeability advection-dominated regimes, salinity increases occurred mostly within membrane units while their effluent salinity initially fell and then rose to match solute delivery. In relatively low-permeability diffusion-dominated regimes, salinity peaked at the membrane upstream boundary and effluent salinity remained low. In both scenarios, however, only modest salinity changes (up to ˜3 g L-1) occurred because of self-limiting tendencies; membrane efficiency declines as salinity rises, and although sediment compaction increases efficiency, it is also decreases permeability and allows diffusive transport to dominate. It appears difficult for ultrafiltration to generate brines as speculated, but widespread and less extreme ultrafiltration effects in the subsurface could be unrecognized. Conditions needed for ultrafiltration are present in settings that include topographically-driven flow systems, confined aquifer systems subjected to injection or withdrawal, compacting basins, and accretionary complexes.

  20. Economic Assessment of an Integrated Membrane System for Secondary Effluent Polishing for Unrestricted Reuse

    Directory of Open Access Journals (Sweden)

    Gideon Oron

    2012-03-01

    Full Text Available Extra treatment stages are required to polish the secondary effluent for unrestricted reuse, primarily for agricultural irrigation. Improved technology for the removal of particles, turbidity, bacteria and cysts, without the use of disinfectants is based on MicroFiltration (MF and UltraFiltration (UF membrane technology and in series with Reverse Osmosis (RO for dissolved solids removal. Field experiments were conducted using a mobile UF and RO membrane pilot unit at a capacity of around 1.0 m3/hr. A management model was defined and tested towards optimal polishing of secondary effluent. The two major purposes of the management model are: (i to delineate a methodology for economic assessment of optimal membrane technology implementation for secondary effluent upgrading for unrestricted use, and; (ii to provide guidelines for optimal RO membrane selection in regards to the pretreatment stage. The defined linear model takes into account the costs of the feed secondary effluent, the UF pretreatment and the RO process. Technological constraints refer primarily to the longevity of the membrane and their performance. Final treatment cost (the objective function includes investment, operation and maintenance expenses, UF pretreatment, RO treatment, post treatment and incentive for low salinity permeate use. The cost range of water for irrigation according to the model is between 15 and 42 US cents per m3.

  1. Study on an integrated process combining ozonation with ceramic ultra-filtration for decentralized supply of drinking water.

    Science.gov (United States)

    Zhu, Jia; Fan, Xiao J; Tao, Yi; Wei, De Q; Zhang, Xi H

    2014-09-19

    An integrated process was specifically developed for the decentralized supply of drinking water from micro-polluted surface water in the rural areas of China. The treatment process combined ozonation with ceramic ultra-filtration (UF), coagulation for pre-treatment and granular activated carbon filtration. A flat-sheet ceramic membrane was used with a cut-off of 60 nm and the measurement of 254 mm (length) × 240 mm (width) × 6 mm (thickness). Ozonation and ceramic UF was set up whthin one reactor. The experimental results showed that the removal efficiencies of the dissolved organic carbon (DOC) and the formation potential of trihalomethanes (THMs), haloacetic acids (HAAs) and ammonia were 80%, 76%, 70% and 90%, respectively; that the turbidity of the product water was below 0.2 NTU and the particle count number (particles larger than 2 μm) was less than 50 counts per mL. The result also showed that all the pathogenic microorganisms were retained by the ceramic and that UF. Ozonation played a critical role in the control of membrane fouling and the removal of contaminants. Exactly, the membrane fouling can be controlled in situ with 3 mg L(-1) ozone at the permeate flux of 80 L m(-2) h(-1), yet the required dosage of ozone was dependent on the quality of the raw water. Therefore, this study is able to provide a highly compacted system for decentralized supply of high-quality drinking water in terms of both chemical and microbiological safety for the rural areas in China.

  2. Removal of antibiotic resistant E. coli in two Norwegian wastewater treatment plants and by nano- and ultra-filtration processes.

    Science.gov (United States)

    Schwermer, Carsten Ulrich; Krzeminski, Pawel; Wennberg, Aina Charlotte; Vogelsang, Christian; Uhl, Wolfgang

    2018-02-01

    The effectivity of different treatment stages at two large wastewater treatment plants (WWTPs) located in Oslo, Norway, to remove antibiotic resistant Escherichia coli from municipal wastewater was investigated. The WWTPs were effective in reducing the total cultivable E. coli. The E. coli in WWTP samples were mainly resistant to ampicillin (6-27%) and trimethoprim-sulfamethoxazole (5-24%), and, to a lesser extent, tetracycline (3-14%) and ciprofloxacin (0-7%). In the first WWTP, a clear decrease in the percentage of E. coli resistant to these antibiotics was found, with the main removal occurring during physical/chemical treatment. In the second WWTP, the percentage of cultivable resistant E. coli did not display a considerable change. During laboratory-scale membrane filtration of WWTP effluents using ultrafiltration (UF) and nanofiltration (NF) membranes, all E. coli, including those resistant to antibiotics, were removed completely. The results imply that UF and NF processes are potent measures to remove antibiotic resistant bacteria (ARB) during post-treatment of WWTP effluents, thus reducing the potential spread of antibiotic resistance in the receiving aquatic environment.

  3. Effect of high and low ultrafiltration volume during hemodialysis on relative blood volume

    NARCIS (Netherlands)

    Dasselaar, JJ; de Jong, PE; Huisman, RM; Franssen, CFM

    2006-01-01

    Achieving an optimal posthemodialysis hydration status may be difficult because objective criteria for dry weight are lacking. Both relative blood volume changes (Delta RBV) at the end of hemodialysis and Delta RBV normalized for ultrafiltration volume (Delta RBV/UF ratio) have been reported to

  4. Slow ultrafiltration for continuous in vivo sampling : application for glucose and lactate in man

    NARCIS (Netherlands)

    Tiessen, RG; Kaptein, WA; Venema, K; Korf, J

    1999-01-01

    Background: An ultrafiltration (UF) technique was developed for continuous subcutaneous (s.c.) sampling and on-line analysis of absolute glucose and lactate concentrations in tissue. The relation between subcutaneous and blood concentrations was studied in men, because a subcutaneous monitoring

  5. Membrane technologies for liquid radioactive waste treatment

    International Nuclear Information System (INIS)

    Chmielewski, A.G.; Harasimowicz, M.; Zakrzewska-Trznadel, G.

    1998-01-01

    At Institute of Nuclear Chemistry and Technology (INCT) the membrane method for purification of radioactive wastes applied such processes as ultrafiltration (UF), 'seeded' ultrafiltration and reverse osmosis (RO) was developed. On the basis of the results obtained in laboratory experiments the pilot plant for radioactive effluents treatment was built. The plant was composed of UF unit (AMICON H 26P30 capillary module) and two RO units (NITTO NTR 739 HF S-4 spiral wound LPRO modules). The capacity of the pilot plant was up to 200 L/h and the specific activity of wastes purified in the system - below 10 4 Bq/L. Decontamination factor for entire system is higher than 5 x10 3 . Another possibility for radioactive wastes treatment is membrane distillation (MD), non-isothermal process employing hydrophobic polymer membrane, which is developed at INCT now. Preliminary tests with liquid radwaste were carried out on laboratory unit with permeation test-cell holding flat sheet membrane. As a hydrophobic barrier membranes made of two polymers were used: polytetrafluoroethylene (PTFE) and polypropylene (PP). The process was arranged in direct contact membrane distillation configuration. The permeate condensed directly in the cold stream (distilled water) and retentate was enriched in radionuclides. The further experiments carried out with capillary module BFMF 06-30-33 (Euro-Sep Ltd.) with polypropylene capillaries, diameter 0.33 mm and cut off 0.6 μm proved previous results. A pilot plant employing GORE-TEX membrane distillation was constructed. The plant can clean the low-level radioactive wastes from nuclear centre, at a throughput about 0.05 m 3 /h

  6. Filtration behavior of casein glycomacropeptide (CGMP) in an enzymatic membrane reactor: fouling control by membrane selection and threshold flux operation

    DEFF Research Database (Denmark)

    Luo, Jianquan; Morthensen, Sofie Thage; Meyer, Anne S.

    2014-01-01

    . In this study, the filtration performance and fouling behavior during ultrafiltration (UF) of CGMP for the enzymatic production of 3′-sialyllactose were investigated. A 5kDa regenerated cellulose membrane with high anti-fouling performance, could retain CGMP well, permeate 3′-sialyllactose, and was found...... to be the most suitable membrane for this application. Low pH increased CGMP retention but produced more fouling. Higher agitation and lower CGMP concentration induced larger permeate flux and higher CGMP retention. Adsorption fouling and pore blocking by CGMP in/on membranes could be controlled by selecting...... a highly hydrophilic membrane with appropriate pore size. Operating under threshold flux could minimize the concentration polarization and cake/gel/scaling layers, but might not avoid irreversible fouling caused by adsorption and pore blocking. The effects of membrane properties, pH, agitation and CGMP...

  7. Photoionization mass spectrometry of UF6

    International Nuclear Information System (INIS)

    Berkowitz, J.

    1979-01-01

    The photoionization mass spectrum of 238 UF 6 was obtained. At 600 A = 20.66 eV, the relative ionic abundances were as follows: UF 6 + , 1.4; UF 5 + , 100; UF + , 17; UF 3 + , approx. 0.7; UF 2 + , very weak; UF + , very weak; U + , essentially zero. The adiabatic ionization potential for UF 6 was 13.897 +- 0.005 eV. The production of UF 5 + begins at approx. 887 A = 13.98 eV, at which energy the UF 6 + partial cross section abruptly declines and then levels off. This behavior suggests the vague possibility of an isotope effect. The UF 4 + signal begins at approx. 725 A = 17.10 eV, at which energy the UF 5 + signal reaches a plateau value. The UF 5 + photoionization yield curve displays some autoionization structure from its threshold to approx. 750 A

  8. Cheese whey protein recovery by ultrafiltration through transglutaminase (TG) catalysis whey protein cross-linking.

    Science.gov (United States)

    Wen-Qiong, Wang; Lan-Wei, Zhang; Xue, Han; Yi, Lu

    2017-01-15

    In whey ultrafiltration (UF) production, two main problems are whey protein recovery and membrane fouling. In this study, membrane coupling protein transglutaminase (TG) catalysis protein cross-linking was investigated under different conditions to find out the best treatment. We found that the optimal conditions for protein recovery involved catalyzing whey protein cross-linking with TG (40U/g whey proteins) at 40°C for 60min at pH 5.0. Under these conditions, the recovery rate was increased 15-20%, lactose rejection rate was decreased by 10%, and relative permeate flux was increase 30-40% compared to the sample without enzyme treatment (control). It was noticeable that the total resistance and cake resistance were decreased after enzyme catalysis. This was mainly due to the increased particle size and decreased zeta potential. Therefore, membrane coupling enzyme catalysis protein cross-linking is a potential means for further use. Copyright © 2016. Published by Elsevier Ltd.

  9. Current advances in screening for bioactive components from medicinal plants by affinity ultrafiltration mass spectrometry.

    Science.gov (United States)

    Chen, Guilin; Huang, Bill X; Guo, Mingquan

    2018-05-21

    Medicinal plants have played an important role in maintaining human health for thousands of years. However, the interactions between the active components in medicinal plants and some certain biological targets during a disease are still unclear in most cases. To conduct the high-throughput screening for small active molecules that can interact with biological targets, which is of great theoretical significance and practical value. The ultrafiltration mass spectrometry (UF-LC/MS) is a powerful bio-analytical method by combining affinity ultrafiltration and liquid chromatography-mass spectrometry (LC/MS), which could rapidly screen and identify small active molecules that bind to biological targets of interest at the same time. Compared with other analytical methods, affinity UF-LC/MS has the characteristics of fast, sensitive and high throughput, and is especially suitable for the complicated extracts of medicinal plants. In this review, the basic principle, characteristics and some most recent challenges in UF-LC/MS have been demonstrated. Meanwhile, the progress and applications of affinity UF-LC/MS in the discovery of the active components from natural medicinal plants and the interactions between small molecules and biological target proteins are also briefly summarised. In addition, the future directions for UF-LC/MS are also prospected. Affinity UF-LC/MS is a powerful tool in studies on the interactions between small active molecules and biological protein targets, especially in the high-throughput screening of active components from the natural medicinal plants. Copyright © 2018 John Wiley & Sons, Ltd.

  10. The Effect of Concentration Factor on Membrane Fouling

    Directory of Open Access Journals (Sweden)

    Appana Lok

    2017-09-01

    Full Text Available Bench-scale systems are often used to evaluate pretreatment methods and operational conditions that can be applied in full-scale ultrafiltration (UF systems. However, the membrane packing density is substantially different in bench and full-scale systems. Differences in concentration factor (CF at the solution–membrane interface as a result of packing density may impact the mass transfer and fouling rate and the applicability of bench-scale systems. The present study compared membrane resistance when considering raw water (CF = 1 and reject water (also commonly referred to as concentrate water (CF > 1 as feed in UF systems operated in deposition (dead-end mode. A positive relationship was observed between the concentration of the organic matter in the solution being filtered and resistance. Bench-scale trials conducted with CF = 1 water were more representative of full-scale operation than trials conducted with elevated CFs when considering membrane resistance and permeate quality. As such, the results of this study indicate that the use of the same feed water as used at full-scale (CF = 1 is appropriate to evaluate fouling in UF systems operated in deposition mode.

  11. Integrated membrane and microbial fuel cell technologies for enabling energy-efficient effluent Re-use in power plants.

    Science.gov (United States)

    Shrestha, Namita; Chilkoor, Govinda; Xia, Lichao; Alvarado, Catalina; Kilduff, James E; Keating, John J; Belfort, Georges; Gadhamshetty, Venkataramana

    2017-06-15

    Municipal wastewater is an attractive alternative to freshwater sources to meet the cooling water needs of thermal power plants. Here we offer an energy-efficient integrated microbial fuel cell (MFC)/ultrafiltration (UF) process to purify primary clarifier effluent from a municipal wastewater treatment plant for use as cooling water. The microbial fuel cell was shown to significantly reduce chemical oxygen demand (COD) in the primary settled wastewater effluent upstream of the UF module, while eliminating the energy demand required to deliver dissolved oxygen in conventional aerobic treatment. We investigated surface modification of the UF membranes to control fouling. Two promising hydrophilic monomers were identified in a high-throughput search: zwitterion (2-(Methacryloyloxy)-ethyl-dimethyl-(3-sulfopropyl ammoniumhydroxide, abbreviated BET SO 3 - ), and amine (2-(Methacryloyloxy) ethyl trimethylammonium chloride, abbreviated N(CH 3 ) 3 + ). Monomers were grafted using UV-induced polymerization on commercial poly (ether sulfone) membranes. Filtration of MFC effluent by membranes modified with BET SO 3 - and N(CH 3 ) 3 + exhibited a lower rate of resistance increase and lower energy consumption than the commercially available membrane. The MFC/UF process produced high quality cooling water that meets the Electrical Power Research Institute (EPRI) recommendations for COD, a suite of metals (Fe, Al, Cu, Zn, Si, Mn, S, Ca and Mg), and offered extremely low corrosion rates (<0.05 mm/yr). A series of AC and DC diagnostic tests were used to evaluate the MFC performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Removal Natural Organic Matter (NOM in Peat Water from Wetland Area by Coagulation-Ultrafiltration Hybrid Process with Pretreatment Two-Stage Coagulation

    Directory of Open Access Journals (Sweden)

    Mahmud Mahmud

    2013-11-01

    Full Text Available The primary problem encountered in the application of membrane technology was membrane fouling. During this time, hybrid process by coagulation-ultrafiltration in drinking water treatment that has been conducted by some research, using by one-stage coagulation. The goal of this research was to investigate the effect of two-stage coagulation as a pretreatment towards performance of the coagulation-ultrafiltration hybrid process for removal NOM in the peat water. Coagulation process, either with the one-stage or two-stage coagulation was very good in removing charge hydrophilic fraction, i.e. more than 98%. NOM fractions of the peat water, from the most easily removed by the two-stage coagulation and one-stage coagulation process was charged hydrophilic>strongly hydrophobic>weakly hydrophobic>neutral hydrophilic. The two-stage coagulation process could removed UV254 and colors with a little better than the one-stage coagulation at the optimum coagulant dose. Neutral hydrophilic fraction of peat water NOM was the most influential fraction of UF membrane fouling. The two-stage coagulation process better in removing the neutral hidrophilic fraction, while removing of the charged hydrophilic, strongly hydrophobic and weakly hydrophobic similar to the one-stage coagulation. Hybrid process by pretreatment with two-stage coagulation, beside can increased removal efficiency of UV254 and color, also can reduced fouling rate of the ultrafiltration membraneIt must not exceed 250 words, contains a brief summary of the text, covering the whole manuscript without being too elaborate on every section. Avoid any abbreviation, unless it is a common knowledge or has been previously stated.

  13. Removal Natural Organic Matter (NOM in Peat Water from Wetland Area by Coagulation-Ultrafiltration Hybrid Process with Pretreatment Two-Stage Coagulation

    Directory of Open Access Journals (Sweden)

    Mahmud Mahmud

    2016-06-01

    Full Text Available The primary problem encountered in the application of membrane technology was membrane fouling. During this time, hybrid process by coagulation-ultrafiltration in drinking water treatment that has been conducted by some research, using by one-stage coagulation. The goal of this research was to investigate the effect of two-stage coagulation as a pretreatment towards performance of the coagulation-ultrafiltration hybrid process for removal NOM in the peat water. Coagulation process, either with the one-stage or two-stage coagulation was very good in removing charge hydrophilic fraction, i.e. more than 98%. NOM fractions of the peat water, from the most easily removed by the two-stage coagulation and one-stage coagulation process was charged hydrophilic>strongly hydrophobic>weakly hydrophobic>neutral hydrophilic. The two-stage coagulation process could removed UV254 and colors with a little better than the one-stage coagulation at the optimum coagulant dose. Neutral hydrophilic fraction of peat water NOM was the most influential fraction of UF membrane fouling. The two-stage coagulation process better in removing the neutral hidrophilic fraction, while removing of the charged hydrophilic, strongly hydrophobic and weakly hydrophobic similar to the one-stage coagulation. Hybrid process by pretreatment with two-stage coagulation, beside can increased removal efficiency of UV254 and color, also can reduced fouling rate of the ultrafiltration membraneIt must not exceed 250 words, contains a brief summary of the text, covering the whole manuscript without being too elaborate on every section. Avoid any abbreviation, unless it is a common knowledge or has been previously stated.

  14. Evaluation of Ultrafiltration Performance for Phospholipid Separation

    Science.gov (United States)

    Aryanti, N.; Wardhani, D. H.; Maulana, Z. S.; Roberto, D.

    2017-11-01

    Ultrafiltration membrane for degumming of crude palm oil has been applied as an alternative method since the membrane process required less procedure than the conventional degumming. This research focused on the examination of ultrafiltration performance for phospholipid separation from model crude palm oil degumming. Specifically, profile flux and rejection, as well as blocking mechanism, were investigated. Feed consisting of Refined Crude Palm Oil - Isopropanol - Lecithin mixtures were represented as crude palm oil degumming. Lecithin was denoted a phospholipid component, and the concentrations of lecithin in feed were varied to 0.1%, 0.2%, and 0.3%. The concentration of phospholipid was determined as phosphor content. At the concentration of lecithin in feed representing phospholipid concentration of 8,45 mg/kg, 8,45 mg/kg, 24,87 mg/kg and 57,58 mg/kg, respectively. Flux profiles confirmed that there was a flux decline during filtration. In addition, the lecithin concentrations do not significantly effect on further flux decline. Rejection characteristic and phospholipid concentration in the permeate showed that the phospholipid rejections by ultrafiltration were in the range of 23-79,5% representing permeate’s phospholipid concentration of 1,73 - 44,25 mg/kg. Evaluation of fouling mechanism by Hermia’s blocking model confirmed that the standard blocking is the dominant mechanism in the ultrafiltration of lecithin mixture.

  15. Thin-film Nanofibrous Composite Membranes Containing Cellulose or Chitin Barrier Layers Fabricated by Ionic Liquids

    Energy Technology Data Exchange (ETDEWEB)

    H Ma; B Hsiao; B Chu

    2011-12-31

    The barrier layer of high-flux ultrafiltration (UF) thin-film nanofibrous composite (TFNC) membranes for purification of wastewater (e.g., bilge water) have been prepared by using cellulose, chitin, and a cellulose-chitin blend, regenerated from an ionic liquid. The structures and properties of regenerated cellulose, chitin, and a cellulose-chitin blend were analyzed with thermogravimetric analysis (TGA) and wide-angle X-ray diffraction (WAXD). The surface morphology, pore size and pore size distribution of TFNC membranes were determined by SEM images and molecular weight cut-off (MWCO) methods. An oil/water emulsion, a model of bilge water, was used as the feed solution, and the permeation flux and rejection ratio of the membranes were investigated. TFNC membranes based on the cellulose-chitin blend exhibited 10 times higher permeation flux when compared with a commercial UF membrane (PAN10, Sepro) with a similar rejection ratio after filtration over a time period of up to 100 h, implying the practical feasibility of such membranes for UF applications.

  16. Recovery of Flavonoids from Orange Press Liquor by an Integrated Membrane Process

    Directory of Open Access Journals (Sweden)

    Alfredo Cassano

    2014-08-01

    Full Text Available Orange press liquor is a by-product generated by the citrus processing industry containing huge amounts of natural phenolic compounds with recognized antioxidant activity. In this work, an integrated membrane process for the recovery of flavonoids from orange press liquors was investigated on a laboratory scale. The liquor was previously clarified by ultrafiltration (UF in selected operating conditions by using hollow fiber polysulfone membranes. Then, the clarified liquor with a total soluble solids (TSS content of 10 g·100 g−1 was pre-concentrated by nanofiltration (NF up to 32 g TSS 100 g−1 by using a polyethersulfone spiral-wound membrane. A final concentration step, up to 47 g TSS 100 g−1, was performed by using an osmotic distillation (OD apparatus equipped with polypropylene hollow fiber membranes. Suspended solids were completely removed in the UF step producing a clarified liquor containing most part of the flavonoids of the original press liquor due to the low rejection of the UF membrane towards these compounds. Flavanones and anthocyanins were highly rejected by the NF membrane, producing a permeate stream with a TSS content of 4.5 g·100 g−1. An increasing of both the flavanones and anthocyanins concentration was observed in the NF retentate by increasing the volume reduction factor (VRF. The final concentration of flavonoids by OD produced a concentrated solution of interest for nutraceutical and pharmaceutical applications.

  17. Recovery of flavonoids from orange press liquor by an integrated membrane process.

    Science.gov (United States)

    Cassano, Alfredo; Conidi, Carmela; Ruby-Figueroa, René

    2014-08-11

    Orange press liquor is a by-product generated by the citrus processing industry containing huge amounts of natural phenolic compounds with recognized antioxidant activity. In this work, an integrated membrane process for the recovery of flavonoids from orange press liquors was investigated on a laboratory scale. The liquor was previously clarified by ultrafiltration (UF) in selected operating conditions by using hollow fiber polysulfone membranes. Then, the clarified liquor with a total soluble solids (TSS) content of 10 g·100 g-1 was pre-concentrated by nanofiltration (NF) up to 32 g TSS 100 g-1 by using a polyethersulfone spiral-wound membrane. A final concentration step, up to 47 g TSS 100 g-1, was performed by using an osmotic distillation (OD) apparatus equipped with polypropylene hollow fiber membranes. Suspended solids were completely removed in the UF step producing a clarified liquor containing most part of the flavonoids of the original press liquor due to the low rejection of the UF membrane towards these compounds. Flavanones and anthocyanins were highly rejected by the NF membrane, producing a permeate stream with a TSS content of 4.5 g·100 g-1. An increasing of both the flavanones and anthocyanins concentration was observed in the NF retentate by increasing the volume reduction factor (VRF). The final concentration of flavonoids by OD produced a concentrated solution of interest for nutraceutical and pharmaceutical applications.

  18. Hybrid MF and membrane bioreactor process applied towards water and indigo reuse from denim textile wastewater.

    Science.gov (United States)

    Couto, Carolina Fonseca; Marques, Larissa Silva; Balmant, Janine; de Oliveira Maia, Andreza Penido; Moravia, Wagner Guadagnin; Santos Amaral, Miriam Cristina

    2018-03-01

    This work investigates the application of a microfiltration (MF)-membrane bioreactor (MBR) hybrid process for textile dyeing process wastewater reclamation. The indigo blue dye was efficiently retained by the MF membrane (100%), which allows its recovery from the concentrate stream. MF promotes 100% of colour removal, and reduces the chemical oxygen demand (COD) and conductivity by about 65% and 25%, respectively, and improves the wastewater biodegradability. MF flux decline was mostly attributed to concentration polarization and the chemical cleaning was efficient enough to recover initial hydraulic resistance. The MBR provides to be a stable process maintaining its COD and ammonia removal efficiency (73% and 100%, respectively) mostly constant throughout and producing a permeate that meets the reuse criteria for some industry activities, such as washing-off and equipment washdown. The use of an MF or ultrafiltration (UF) membrane in the MBR does not impact the MBR performance in terms of COD removal. Although the membrane of MBR-UF shows permeability lower than MBR-MF membrane, the UF membrane contributes to a more stable operation in terms of permeability.

  19. Recovery of Whey Proteins and Enzymatic Hydrolysis of Lactose Derived from Casein Whey Using a Tangential Flow Ultrafiltration Module

    Science.gov (United States)

    Das, Bipasha; Bhattacharjee, Sangita; Bhattacharjee, Chiranjib

    2013-09-01

    In this study, ultrafiltration (UF) of pretreated casein whey was carried out in a cross-flow module fitted with 5 kDa molecular weight cut-off polyethersulfone membrane to recover whey proteins in the retentate and lactose in the permeate. Effects of processing conditions, like transmembrane pressure and pH on permeate flux and rejection were investigated and reported. The polarised layer resistance was found to increase with time during UF even in this high shear device. The lactose concentration in the permeate was measured using dinitro salicylic acid method. Enzymatic kinetic study for lactose hydrolysis was carried out at three different temperatures ranging from 30 to 50 °C using β-galactosidase enzyme. The glucose formed during lactose hydrolysis was analyzed using glucose oxidase-peroxidase method. Kinetics of enzymatic hydrolysis of lactose solution was found to follow Michaelis-Menten model and the model parameters were estimated by Lineweaver-Burk plot. The hydrolysis rate was found to be maximum (with Vmax = 5.5091 mmol/L/min) at 30 °C.

  20. Performance evaluation of carbon nanotube enhanced membranes for SWRO pretreatment application

    KAUST Repository

    Lee, Jieun

    2016-04-25

    Multi-wall carbon nanotube (MWCNT) membrane was tested for SWRO pretreatment. The MWCNT membrane itself showed a superior permeate flux (321.3 LMH/bar), which was 4-times as polyethersulfone ultrafiltration (PES-UF) membrane. Reduction of dissolved organic matter improved to 66% with fewer amounts of powder activated carbon (PAC) (0.5 g/L) in MWCNT membrane filtration maintaining a high permeate flux of 600 LMH/bar. It was due to the increased porosity (84.5%) and hydrophilicity (52.9°) by incorporating MWCNT/polyaniline into PES membrane. Ionic strength affected organic removal in seawater filtration by altering electrostatic interaction between organic matter and surface charge of the positively charged MWCNT membrane.

  1. Influence of fertilizer draw solution properties on the process performance and microbial community structure in a side-stream anaerobic fertilizer-drawn forward osmosis - ultrafiltration bioreactor.

    Science.gov (United States)

    Kim, Youngjin; Li, Sheng; Chekli, Laura; Phuntsho, Sherub; Ghaffour, Noreddine; Leiknes, TorOve; Shon, Ho Kyong

    2017-09-01

    In this study, a side-stream anaerobic fertilizer-drawn forward osmosis (FDFO) and ultrafiltration (UF) membrane bioreactor (MBR) hybrid system was proposed and operated for 55days. The FDFO performance was first investigated in terms of flux decline with various fertilizers draw solution. Flux decline was very severe with all fertilizers due to the absence of aeration and the sticky property of sludge. Flux recovery by physical cleaning varied significantly amongst tested fertilizers which seriously affected biofouling in FDFO via reverse salt flux (RSF). Besides, RSF had a significant impact on nutrient accumulation in the bioreactor. These results indicated that nutrient accumulation negatively influenced the anaerobic activity. To elucidate these phenomena, bacterial and archaeal community structures were analyzed by pyrosequencing. Results showed that bacterial community structure was affected by fertilizer properties with less impact on archaeal community structure, which resulted in a reduction in biogas production and an increase in nitrogen content. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Influence of fertilizer draw solution properties on the process performance and microbial community structure in a side-stream anaerobic fertilizer-drawn forward osmosis – ultrafiltration bioreactor

    KAUST Repository

    Kim, Youngjin

    2017-02-27

    In this study, a side-stream anaerobic fertilizer-drawn forward osmosis (FDFO) and ultrafiltration (UF) membrane bioreactor (MBR) hybrid system was proposed and operated for 55 days. The FDFO performance was first investigated in terms of flux decline with various fertilizers draw solution. Flux decline was very severe with all fertilizers due to the absence of aeration and the sticky property of sludge. Flux recovery by physical cleaning varied significantly amongst tested fertilizers which seriously affected biofouling in FDFO via reverse salt flux (RSF). Besides, RSF had a significant impact on nutrient accumulation in the bioreactor. These results indicated that nutrient accumulation negatively influenced the anaerobic activity. To elucidate these phenomena, bacterial and archaeal community structures were analyzed by pyrosequencing. Results showed that bacterial community structure was affected by fertilizer properties with less impact on archaeal community structure, which resulted in a reduction in biogas production and an increase in nitrogen content.

  3. Stirred cell ultrafiltration of lignin from black liquor generated from South African kraft mills

    CSIR Research Space (South Africa)

    Kekana, Paul

    2016-12-01

    Full Text Available Ultrafiltration of lignin from black liquor was carried out in a stirred batch cell using polyethersulfone membranes. Parameters such as operating pressure, feed concentration, stirring rate and membrane cut-off size were varied and their effects...

  4. Ultrafiltration to reuse laundering wash water

    DEFF Research Database (Denmark)

    Giagnorio, Mattia; Søtoft, Lene Fjerbæk; Tiraferri, Alberto

    2017-01-01

    Laundering industry consumes and discharges large amounts of water and surfactants, and the demand of surface active agents used for washing is increasing worldwide. Some of these substances are considered contaminants of emerging concern, as they persist in the environment. This work aimed...... at evaluating the feasibility of ultrafiltration as a method to treat the wash wastewater and possibly reuse the surfactant-rich permeate stream in laundry facilities. In particular, evaluation of surfactant recovery was performed through analysis of the permeate flux and properties obtained through polymeric...... and ceramic membranes. Wash water samples were collected at an industrial laundering facility for hospital linen and filtered through different ultrafiltration membranes with varying molecular weight cut-off. The critical micelle concentration of the detergent was quantified, and capillarity measurements were...

  5. Application of volume-retarded osmosis and low-pressure membrane hybrid process for water reclamation

    KAUST Repository

    Im, Sung-Ju

    2017-11-15

    A new concept of volume-retarded osmosis and low-pressure membrane (VRO-LPM) hybrid process was developed and evaluated for the first time in this study. Commercially available forward osmosis (FO) and ultrafiltration (UF) membranes were employed in a VRO-LPM hybrid process to overcome energy limitations of draw solution (DS) regeneration and production of permeate in the FO process. To evaluate its feasibility as a water reclamation process, and to optimize the operational conditions, cross-flow FO and dead-end mode UF processes were individually evaluated. For the FO process, a DS concentration of 0.15 g mL−1 of polysulfonate styrene (PSS) was determined to be optimal, having a high flux with a low reverse salt flux. The UF membrane with a molecular weight cut-off of 1 kDa was chosen for its high PSS rejection in the LPM process. As a single process, UF (LPM) exhibited a higher flux than FO, but this could be controlled by adjusting the effective membrane area of the FO and UF membranes in the VRO-LPM system. The VRO-LPM hybrid process only required a circulation pump for the FO process. This led to a decrease in the specific energy consumption of the VRO-LPM process for potable water production, that was similar to the single FO process. Therefore, the newly developed VRO-LPM hybrid process, with an appropriate DS selection, can be used as an energy efficient water production method, and can outperform conventional water reclamation processes.

  6. Application of volume-retarded osmosis and low-pressure membrane hybrid process for water reclamation

    KAUST Repository

    Im, Sung-Ju; Choi, Jungwon; Lee, Jung Gil; Jeong, Sanghyun; Jang, Am

    2017-01-01

    A new concept of volume-retarded osmosis and low-pressure membrane (VRO-LPM) hybrid process was developed and evaluated for the first time in this study. Commercially available forward osmosis (FO) and ultrafiltration (UF) membranes were employed in a VRO-LPM hybrid process to overcome energy limitations of draw solution (DS) regeneration and production of permeate in the FO process. To evaluate its feasibility as a water reclamation process, and to optimize the operational conditions, cross-flow FO and dead-end mode UF processes were individually evaluated. For the FO process, a DS concentration of 0.15 g mL−1 of polysulfonate styrene (PSS) was determined to be optimal, having a high flux with a low reverse salt flux. The UF membrane with a molecular weight cut-off of 1 kDa was chosen for its high PSS rejection in the LPM process. As a single process, UF (LPM) exhibited a higher flux than FO, but this could be controlled by adjusting the effective membrane area of the FO and UF membranes in the VRO-LPM system. The VRO-LPM hybrid process only required a circulation pump for the FO process. This led to a decrease in the specific energy consumption of the VRO-LPM process for potable water production, that was similar to the single FO process. Therefore, the newly developed VRO-LPM hybrid process, with an appropriate DS selection, can be used as an energy efficient water production method, and can outperform conventional water reclamation processes.

  7. Application of volume-retarded osmosis and low-pressure membrane hybrid process for water reclamation.

    Science.gov (United States)

    Im, Sung-Ju; Choi, Jungwon; Lee, Jung-Gil; Jeong, Sanghyun; Jang, Am

    2018-03-01

    A new concept of volume-retarded osmosis and low-pressure membrane (VRO-LPM) hybrid process was developed and evaluated for the first time in this study. Commercially available forward osmosis (FO) and ultrafiltration (UF) membranes were employed in a VRO-LPM hybrid process to overcome energy limitations of draw solution (DS) regeneration and production of permeate in the FO process. To evaluate its feasibility as a water reclamation process, and to optimize the operational conditions, cross-flow FO and dead-end mode UF processes were individually evaluated. For the FO process, a DS concentration of 0.15 g mL -1 of polysulfonate styrene (PSS) was determined to be optimal, having a high flux with a low reverse salt flux. The UF membrane with a molecular weight cut-off of 1 kDa was chosen for its high PSS rejection in the LPM process. As a single process, UF (LPM) exhibited a higher flux than FO, but this could be controlled by adjusting the effective membrane area of the FO and UF membranes in the VRO-LPM system. The VRO-LPM hybrid process only required a circulation pump for the FO process. This led to a decrease in the specific energy consumption of the VRO-LPM process for potable water production, that was similar to the single FO process. Therefore, the newly developed VRO-LPM hybrid process, with an appropriate DS selection, can be used as an energy efficient water production method, and can outperform conventional water reclamation processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. F and H Area Effluent Treatment Facility (F/H ETF): ultrafiltration and hyperfiltration systems testing at Carre, Inc. with simulated F and H area effluents

    International Nuclear Information System (INIS)

    Ryan, J.P.

    1984-01-01

    The F and H Area Effluent Treatment Facility is essentially a four-stage process that will decontaminate the waste water that is currently being discharged to seepage basins in the Separations Areas. The stages include pretreatment, reverse osmosis, ion exchange, and evaporation. A series of tests were performed at Carre, Inc. (Seneca, SC) from March 5 through March 13, to determine the usefulness of ultrafiltration (UF) in the pretreatment stage of the ETF. The results of that testing program indicate that UF would be an excellent means of removing entrained activity from the 200 Area process effluents. Hyperfiltration (HF) was also tested as a means of providing an improved concentration factor from the reverse osmosis stage. The results show that the membranes that were tested would not reject salt well enough at high salt concentrations to be useful in the final reverse osmosis stage. However, there are several membranes which are commercially available that would provide the needed rejection if they could be applied (dynamically) on the Carre support structure. This avenue is still being explored, as theoretically, it could eliminate the need for the F/H ETF evaporator

  9. Impact of the fouling mechanism on enzymatic depolymerization of xylan in different configurations of membrane reactors

    DEFF Research Database (Denmark)

    Mohd Sueb, Mohd Shafiq Bin; Luo, Jianquan; Meyer, Anne S.

    2017-01-01

    In order to maximize enzymatic xylan depolymerization while simultaneously purifying the resulting monosaccharide (xylose), different ultrafiltration (UF) membrane reactor configurations were evaluated. Initial results showed that the two hydrolytic enzymes required for complete depolymerization...... which hindered enzymatic attack in addition to fouling. Reaction with both enzymes followed by UF was found to be the optimal configuration, providing at least 40% higher xylan hydrolysis than the cascade configuration (involving sequential reaction with each of the enzymes separately......) and the simultaneous reaction-filtration with both enzymes, respectively. This study thus confirmed that the reactor configuration has a crucial impact on the performance of both the reaction and the separation process of xylose during enzymatic xylan degradation, and that the type of fouling mechanism varies...

  10. Template-mediated synthesis of periodic membranes for improved liquid-phase separations

    International Nuclear Information System (INIS)

    Groger, H.

    1997-01-01

    Solid/liquid separations of particulates in waste streams will benefit from design and development of ultrafiltration (UF) membranes with uniform, tailorable pore size and chemical, thermal, and mechanical stability. Such membranes will perform solid/liquid separations with high selectivity, permeance, lifetime, and low operating costs. Existing organic and inorganic membrane materials do not adequately meet all these requirements. An innovative solution to the need for improved inorganic membranes is the application of mesoporous ceramics with narrow pore-size distributions and tailorable pore size (1.5 to 10 nm) that have recently been shown to form with the use of organic surfactant molecules and surfactant assemblies as removable templates. This series of porous ceramics, designated MCM-41, consists of silica or aluminosilicates distinguished by periodic arrays of uniform channels. In this Phase I Small Business Innovation Research program, American Research Corporation of Virginia will demonstrate the use of supported MCM-41 thin films deposited by a proprietary technique, as UF membranes. Technical objectives include deposition in thin, defect-free periodic mesoporous MCM-41 membranes on porous supports; measurement of membrane separation factors, permeance, and fouling; and measurement of membrane lifetime as part of an engineering and economic analysis

  11. Template-mediated synthesis of periodic membranes for improved liquid-phase separations

    Energy Technology Data Exchange (ETDEWEB)

    Groger, H. [American Research Corp. of Virginia, Radford, VA (United States)

    1997-10-01

    Solid/liquid separations of particulates in waste streams will benefit from design and development of ultrafiltration (UF) membranes with uniform, tailorable pore size and chemical, thermal, and mechanical stability. Such membranes will perform solid/liquid separations with high selectivity, permeance, lifetime, and low operating costs. Existing organic and inorganic membrane materials do not adequately meet all these requirements. An innovative solution to the need for improved inorganic membranes is the application of mesoporous ceramics with narrow pore-size distributions and tailorable pore size (1.5 to 10 nm) that have recently been shown to form with the use of organic surfactant molecules and surfactant assemblies as removable templates. This series of porous ceramics, designated MCM-41, consists of silica or aluminosilicates distinguished by periodic arrays of uniform channels. In this Phase I Small Business Innovation Research program, American Research Corporation of Virginia will demonstrate the use of supported MCM-41 thin films deposited by a proprietary technique, as UF membranes. Technical objectives include deposition in thin, defect-free periodic mesoporous MCM-41 membranes on porous supports; measurement of membrane separation factors, permeance, and fouling; and measurement of membrane lifetime as part of an engineering and economic analysis.

  12. Preparation and Preliminary Dialysis Performance Research of Polyvinylidene Fluoride Hollow Fiber Membranes

    Science.gov (United States)

    Zhang, Qinglei; Lu, Xiaolong; Liu, Juanjuan; Zhao, Lihua

    2015-01-01

    In this study, the separation properties of Polyvinylidene fluoride (PVDF) hollow fiber hemodialysis membranes were improved by optimizing membrane morphology and structure. The results showed that the PVDF membrane had better mechanical and separation properties than Fresenius Polysulfone High-Flux (F60S) membrane. The PVDF membrane tensile stress at break, tensile elongation and bursting pressure were 11.3 MPa, 395% and 0.625 MPa, respectively. Ultrafiltration (UF) flux of pure water reached 108.2 L∙h−1∙m−2 and rejection of Albumin from bovine serum was 82.3%. The PVDF dialyzers were prepared by centrifugal casting. The influences of membrane area and simulate fluid flow rate on dialysis performance were investigated. The results showed that the clearance rate of urea and Lysozyme (LZM) were improved with increasing membrane area and fluid flow rate while the rejection of albumin from bovine serum (BSA) had little influence. The high-flux PVDF dialyzer UF coefficient reached 62.6 mL/h/mmHg. The PVDF dialyzer with membrane area 0.69 m2 has the highest clearance rate to LZM and urea. The clearance rate of LZM was 66.8% and urea was 87.7%. PMID:25807890

  13. Sequential micro and ultrafiltration of distillery wastewater

    Directory of Open Access Journals (Sweden)

    Vasić Vesna M.

    2015-01-01

    Full Text Available Water reuse and recycling, wastewater treatment, drinking water production and environmental protection are the key challenges for the future of our planet. Membrane separation technologies for the removal of all suspended solids and a fraction of dissolved solids from wastewaters, are becoming more and more promising. Also, these processes are playing a major role in wastewater purification systems because of their high potential for recovery of water from many industrial wastewaters. The aim of this work was to evaluate the application of micro and ultrafiltration for distillery wastewater purification in order to produce water suitable for reuse in the bioethanol industry. The results of the analyses of the permeate obtained after micro and ultrafiltration showed that the content of pollutants in distillery wastewater was significantly reduced. The removal efficiency for chemical oxygen demand, dry matter and total nitrogen was 90%, 99.2% and 99.9%, respectively. Suspended solids were completely removed from the stillage.

  14. Preparation of robust braid-reinforced poly(vinyl chloride) ultrafiltration hollow fiber membrane with antifouling surface and application to filtration of activated sludge solution.

    Science.gov (United States)

    Zhou, Zhuang; Rajabzadeh, Saeid; Fang, Lifeng; Miyoshi, Taro; Kakihana, Yuriko; Matsuyama, Hideto

    2017-08-01

    Braid-reinforced hollow fiber membranes with high mechanical properties and considerable antifouling surface were prepared by blending poly(vinyl chloride) (PVC) with poly(vinyl chloride-co-poly(ethylene glycol) methyl ether methacrylate) (poly(VC-co-PEGMA)) copolymer via non-solvent induced phase separation (NIPS). The tensile strength of the braid-reinforced PVC hollow fiber membranes were significantly larger than those of previously reported various types of PVC hollow fiber membranes. The high interfacial bonding strength indicated the good compatibility between the coating materials and the surface of polyethylene terephthalate (PET)-braid. Owing to the surface segregation phenomena, the membrane surface PEGMA coverage increased upon increasing the poly(VC-co-PEGMA)/PVC blending ratio, resulting in higher hydrophilicities and bovine serum albumin (BSA) repulsion. To compare the fouling properties, membranes with similar PWPs were prepared by adjusting the dope solution composition to eliminate the effect of hydrodynamic conditions on the membrane fouling performance. The blend membranes surface exhibited considerable fouling resistance to the molecular adsorption from both BSA solution and activated sludge solution. In both cases, the flux recovered to almost 80% of the initial flux using only water backflush. Considering their great mechanical properties and antifouling resistance to activated sludge solution, these novel membranes show good potential for application in wastewater treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Highly antifouling and antibacterial performance of poly (vinylidene fluoride) ultrafiltration membranes blending with copper oxide and graphene oxide nanofillers for effective wastewater treatment.

    Science.gov (United States)

    Zhao, Chuanqi; Lv, Jinling; Xu, Xiaochen; Zhang, Guoquan; Yang, Yuesuo; Yang, Fenglin

    2017-11-01

    Innovation and effective wastewater treatment technology is still in great demand given the emerging contaminants frequently spotted from the aqueous environment. By blending with poly (vinylidene fluoride) (PVDF), the strong hydrophilic graphene oxide (GO) and antibacterial copper oxide (Cu x O) were used as nanofillers to develop the novel, highly antifouling composite membranes via phase inversion process in our latest work. The existence and dispersion of GO and Cu x O posed a significant role on morphologies, structures, surface composition and hydrophilicity of the developed composite membranes, confirmed by SEM, TEM, FTIR and XPS in depth characterization. The SEM images showed that the modified membranes presented a lower resistant structure with developed finger-like macrovoids and thin-walled even interconnected sponge-like pores after adding nanofillers, much encouraging membrane permeation. The XPS results revealed that Cu x O contained Cu 2 O and CuO in the developed membrane and the Cu 2 O nanoparticles were dominant accounting for about 79.3%; thus the modified membrane specifically exhibited an efficient antibacterial capacity. Due to the hydrophilic and bactericidal membrane surface, the composite membranes demonstrated an excellent antifouling performance, including higher flux recovery rate, more resistant against accumulated contaminants and lower filtration resistance, especially lower irreversible resistance. The antifouling property, especially anti-irreversible fouling, was significantly improved, showing a significant engineering potential. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Reactions UF4 - ClO2F and UF5 - ClO2F

    International Nuclear Information System (INIS)

    Benoit, Raymond; Besnard, Ginette; Hartmanshenn, Olivier; Luce, Michel; Mougin, Jacques; Pelissie, Jean

    1970-02-01

    The study of the reaction UF 4 - ClO 2 F between 0 deg. and 100 deg. C, by various techniques (micro-sublimation, isopiestic method, IR and UV spectrography, thermogravimetry and X-ray diffraction) shows that intermediate steps are possible before the production of UF 5 . The whole reaction may be schematised by two equations: (1) n UF 4 + ClO 2 F → n UF x + ClO 2 (4 4 + ClO 2 F → UF x + 1/2 Cl 2 + O 2 . The more the temperature rises, the more the second equation becomes experimentally verified. The reaction at 0 deg. C between UF 5 and ClO 2 F may be represented by: UF 5 + ClO 2 F → UF 6 ClO 2 . The reactions: UF 5 + ClO 2 F → UF 6 + ClO 2 , UF 5 + ClO 2 F → UF 6 + 1/2 Cl 2 + O 2 are verified, the first and the second at 25 deg. C., the second from 50 deg. to 150 deg. C. From the results of AGRON it is possible to predict the residual solids before complete volatilization as UF 6 . The IR spectra of ClO 2 F adsorbed on UF 4 and UF x at 60 deg. C have been compared with those of gaseous ClO 2 F and UF 6 adsorbed on UF 4 . (authors) [fr

  17. Membrane Fouling Potential of Secondary Effluent Organic Matter (EfOM) from Conventional Activated Sludge Process

    KAUST Repository

    Wei, Chunhai; Amy, Gary L.

    2012-01-01

    Secondary effluent organic matter (EfOM) from a conventional activated sludge process was filtered through constant-pressure dead-end filtration tests with a sequential ultrafiltration (UF, molecular weight cut-off (MWCO) of 10k Dalton) and nanofiltration (NF, MWCO of 200 Dalton) array to investigate its membrane fouling potential. Advanced analytical methods including liquid chromatography with online carbon detection (LC-OCD) and fluorescent excitation-emission matrix (F-EEM) were employed for EfOM characterization. EfOM consisted of humic substances and building blocks, low molecular weight (LMW) neutrals, biopolymers (mainly proteins) and hydrophobic organics according to the sequence of their organic carbon fractions. The UF rejected only biopolymers and the NF rejected most humics and building blocks and a significant part of LMW neutrals. Simultaneous occurrence of cake layer and standard blocking during the filtration process of both UF and NF was identified according to constant-pressure filtration equations, which was possibly caused by the heterogeneous nature of EfOM with a wide MW distribution (several ten to several million Dalton). Thus the corresponding two fouling indices (kc for cake layer and ks for standard blocking) from UF and NF could characterize the fouling potential of macromolecular biopolymers and low to intermediate MW organics (including humics, building blocks, LMW neutrals), respectively. Compared with macromolecular biopolymers, low to intermediate MW organics exhibited a much higher fouling potential due to their lower molecular weight and higher concentration.

  18. Technical feasibility study of a low-cost hybrid PAC-UF system for wastewater reclamation and reuse: a focus on feedwater production for low-pressure boilers.

    Science.gov (United States)

    Amosa, Mutiu Kolade; Jami, Mohammed Saedi; Alkhatib, Ma'an Fahmi R; Majozi, Thokozani

    2016-11-01

    This study has applied the concept of the hybrid PAC-UF process in the treatment of the final effluent of the palm oil industry for reuse as feedwater for low-pressure boilers. In a bench-scale set-up, a low-cost empty fruit bunch-based powdered activated carbon (PAC) was employed for upstream adsorption of biotreated palm oil mill effluent (BPOME) with the process conditions: 60 g/L dose of PAC, 68 min of mixing time and 200 rpm of mixing speed, to reduce the feedwater strength, alleviate probable fouling of the membranes and thus improve the process flux (productivity). Three polyethersulfone ultrafiltration membranes of molecular weight cut-off (MWCO) of 1, 5 and 10 kDa were investigated in a cross-flow filtration mode, and under constant transmembrane pressures of 40, 80, and 120 kPa. The permeate qualities of the hybrid processes were evaluated, and it was found that the integrated process with the 1 kDa MWCO UF membrane yielded the best water quality that falls within the US EPA reuse standard for boiler-feed and cooling water. It was also observed that the permeate quality is fit for extended reuse as process water in the cement, petroleum and coal industries. In addition, the hybrid system's operation consumed 37.13 Wh m -3 of energy at the highest applied pressure of 120 kPa, which is far lesser than the typical energy requirement range (0.8-1.0 kWh m -3 ) for such wastewater reclamation.

  19. Improved surface hydrophilicity and antifouling property of polysulfone ultrafiltration membrane with poly(ethylene glycol) methyl ether methacrylate grafted graphene oxide nanofillers

    Science.gov (United States)

    Wang, Haidong; Lu, Xiaofei; Lu, Xinglin; Wang, Zhenghui; Ma, Jun; Wang, Panpan

    2017-12-01

    In this study, the GO-g-P(PEGMA) nanoplates were first synthesized by grafting hydrophilic poly (poly (ethylene glycol) methyl ether methacrylate) via surface-initiated atom transfer radical polymerization (SI-ATRP) method. A novel polysulfone (PSF) nanocomposite membrane using GO-g-P(PEGMA) nanoplates as nanofillers was fabricated. FTIR, TGA, 1H NMR, GPC and TEM were applied to verify the successful synthesis of the prepared nanoplates, while SEM, AFM, XPS, contact angle goniometry and filtration experiments were used to characterize the fabricated nanocomposite membranes. It was found that the new prepared nanofillers were well dispersed in organic PSF matrix, and the PSF/GO-g-P(PEGMA) nanocomposite membrane showed significant improvements in water flux and flux recovery rate. Based on the results of resistance-in-series model, the nanocomposite membrane exhibited superior resistance to the irreversible fouling. The excellent filtration and antifouling performance are attributed to the segregation of GO-g-P(PEMGA) nanofillers toward the membrane surface and the pore walls. Notably, the blended nanofillers appeared a stable retention in/on nanocomposite membrane after 30 days of washing time. The demonstrated method of synthesis GO-g-P(PEGMA) in this study can also be extended to preparation of other nanocomposite membrane in future.

  20. Integration of biological method and membrane technology in treating palm oil mill effluent

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yejian; YAN Li; QIAO Xiangli; CHI Lina; NIU Xiangjun; MEI Zhijian; ZHANG Zhenjia

    2008-01-01

    Palm oil industry is the most important agro-industry in Malaysia, but its by-product-palm oil mill effluent (POME), posed a great threat to water environment. In the past decades, several treatment and disposal methods have been proposed and investigated to solve this problem. A two-stage pilot-scale plant was designed and constructed for POME treatment. Anaerobic digestion and aerobic biodegradation constituted the first biological stage, while ultrafiltration (UF) and reverse osmosis (RO) membrane units were combined as the second membrane separation stage. In the anaerobic expanded granular sludge bed (EGSB) reactor, about 43% organic matter in POME was converted into biogas, and COD reduction efficiency reached 93% and 22% in EGSB and the following aerobic reactor, respectively. With the treatment in the first biological stage, suspended solids and oil also decreased to a low degree. All these alleviated the membrane fouling and prolonged the membrane life. In the membrane process unit, almost all the suspended solids were captured by UF membranes, while RO membrane excluded most of the dissolved solids or inorganic salts from RO permeate. After the whole treatment processes, organic matter in POME expressed by BOD and COD was removed almost thoroughly. Suspended solids and color were not detectable in RO permeate any more, and mineral elements only existed in trace amount (except for K and Na). The high-quality effluent was crystal clear and could be used as the boiler feed water.

  1. Comparative Study on Performance and Organic Fouling of ZrO2 Ceramic Membranes in Ultrafiltration of Synthetic Water and Wastewater Treatment Plant Effluent

    KAUST Repository

    Li, Cen

    2011-07-01

    Adsorption of organic matter on ceramic membrane can lead to hydraulic-irreversible fouling, which decreases the permeate flux and the cost-efficiency of membrane devices. In order to optimize the filtration process, detailed information is necessary about the organic fouling mechanisms on ceramic membranes. In this study, dead-end filtration experiments of both synthetic water and secondary effluent from a wastewater treatment plant (WWTP) were conducted on a ZrO2 ceramic membrane. The experiment results of synthetic water showed that humic acid (HA) was able to be adsorbed by the ZrO2 membrane and cause permeate flux decline; and that HA-tryptophan mixture, at the same DOC level, promoted the filtration flux decline; DOC removal in the case of HA-tryptophan was lower than that of HA alone. It seems that hydrophilic organic matter with low molecular weight have some specific contribution to the organic fouling of the ZrO2 membrane. The results also suggest that tryptophan molecules were preferentially adsorbed on the membrane at the beginning, exposing their hydrophobic sides which might further adsorb HA from the feed water. During the filtration of WWTP effluent, protein-like substances (mainly tryptophan-like) were also preferentially adsorbed on the membrane compared with humic-like ones in the initial few cycles of filtration. More humic-like substances were adsorbed in the following filtration cycles due to the increase of membrane hydrophobicity. A significant rise in hydraulic-irreversible flux decline was obtained by decreasing pH from near pHpzc to below pHpzc of the membrane. It suggests that a positively charged surface is preferred for HA adsorption. Ionic strength increase did not affect the filtration of HA, but it lessened the hydraulic-irreversible flux decline of HA-tryptophan filtration. The adsorption of HA-tryptophan can be attributed to outersphere interaction while HA adsorption is mainly caused by inner-sphere interaction. The results of

  2. Survey of technological trends in functional membrane materials; Kinosei makuzai ni kansuru gijutsu doko chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1979-03-01

    Materials for membranes with novel functions are surveyed. The survey is focused on 10 subjects, which are high-performance RO (reverse osmosis)/UF (ultrafiltration) membranes; development of an energy-efficient secondary treatment system for urban wastewater using pollution-free membranes; high-performance ion exchange membranes; artificial lung membranes; hydrogen separation membranes (hydrogen as energy); development of an energy-efficient combustion system using gas separation membranes (oxygen-enriched membranes); organic matter separation membranes; enzyme-aided chemical reaction membranes and their application; development of a distilling ship; and functional membranes making use of photosynthesis. Discussed in this connection are the outlines of the technologies, the need of their development, methods and contents of the development efforts, and the effects and impacts of their development. The survey further concerns the particulars of the trends in novel technologies about functional membrane materials development, covering gas separation and liquid separation technologies; chemical reaction membranes; and enzyme-aided chemical reaction membranes and their application systems. As for their application, the survey covers the field of application of desalinated or ultrapure water; field of application of food fermentation technologies; industrial wastewater, valuable materials recovery, and urban wastewater treatment; and application to medical systems. (NEDO)

  3. Oily bilge water treatment with a tubular ultrafiltration system

    Energy Technology Data Exchange (ETDEWEB)

    Harris, L.R.; Jackson, D.F.; Schatzberg, P.

    1976-11-01

    The Navy has been developing various oil pollution abatement systems. One potential process for the separation of oil in bilge water is ultrafiltration, a pressure-driven membrane process which can separate, concentrate, and fractionate macromolecular solutes and suspended species from water. A tubular ultrafiltration system using cellulosic and noncellulosic membranes was tested with bilge oil obtained from a patrol craft. Tests were also conducted with tap water, river water, a turbine lubricating oil, and a fuel oil, alone and in combination with a nonionic detergent. The addition of the detergent was observed to result in a steeper flux decline than when any of the fluids were evaluated alone. Both membrane types produced a permeate with an oil content generally less than 15 mg/l. Although the noncellulosic membranes exhibited higher flux rates than the cellulosic membranes, only the former could be restored by a cleaning operation to its initial water flux after experiencing a decline in flux. A cumulative irreversible flux decline was exhibited by the cellulosic membrane. Cleaning operations, some of which were time-consuming, consisted of flushing the membrane with ultrafiltrate, distilled water, tap water, or the manufacturer's enzyme-detergent formulation. Only the last of these, when employed at elevated temperature (125/sup 0/F), restored the initial water flux of the noncellulosic membrane.

  4. Membrane processing technology in the food industry: food processing, wastewater treatment, and effects on physical, microbiological, organoleptic, and nutritional properties of foods.

    Science.gov (United States)

    Kotsanopoulos, Konstantinos V; Arvanitoyannis, Ioannis S

    2015-01-01

    Membrane processing technology (MPT) is increasingly used nowadays in a wide range of applications (demineralization, desalination, stabilization, separation, deacidification, reduction of microbial load, purification, etc.) in food industries. The most frequently applied techniques are electrodialysis (ED), reverse osmosis (RO), nanofiltration (NF), ultrafiltration (UF), and microfiltration (MF). Several membrane characteristics, such as pore size, flow properties, and the applied hydraulic pressure mainly determine membranes' potential uses. In this review paper the basic membrane techniques, their potential applications in a large number of fields and products towards the food industry, the main advantages and disadvantages of these methods, fouling phenomena as well as their effects on the organoleptic, qualitative, and nutritional value of foods are synoptically described. Some representative examples of traditional and modern membrane applications both in tabular and figural form are also provided.

  5. Microfiltration and ultrafiltration as a post-treatment of biogas plant digestates for producing concentrated fertilizers

    DEFF Research Database (Denmark)

    Camilleri Rumbau, Maria Salud; Norddahl, Birgir; Wei, Jiang

    2015-01-01

    Biogas plant digestate liquid fractions can be concentrated by microfiltration and ultrafiltration. Two types of microfiltration membranes (polysulphone (PS) and surface-modified polyvinylidene fluoride (PVDF)) were used to process digestate liquid fractions, and to assess their applicability in ...

  6. Ultrafiltration concept for separating oil from water. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Goldsmith, R.L.; Schrab H.

    1973-01-01

    Discharge of oily wastes from shipboard operations of deballasting, bilge pumping, and slop tank cleaning constitutes a serious water pollution problem. Membrane ultrafiltration was studied in this project as a means of generating a highly purified water from a variety of oily wastes.

  7. Investigations of the Effects of Biocide Dosing and Chemical Cleaning on the Organic Carbon Removal in an Integrated Ultrafiltration - Nanofiltration Desalination Pilot Plant

    KAUST Repository

    Khojah, Bayan A.

    2017-12-01

    Membrane desalination has become one of the most important desalination technologies used in the world. It provides high water quality for numerous applications and it demonstrates excellent desalination efficiency. One of the most troubling drawbacks of membrane desalination is membrane fouling. It decreases the performance of the membranes and increases the energy requirement. Two of the most important causes of fouling are microbes and organic matter. Hence, to maintain an optimized desalination performance, routine inspection of microbial and organic contents of water is crucial for desalination plants. In this study, water samples were obtained from different treatment points in an ultrafiltration (UF)/nanofiltration (NF) seawater desalination pilot plant. This was performed to better understand how the water quality changes along the desalination scheme. The effect of fouling control techniques, including Chemically Enhanced Backwash (CEB), Cleaning in Place (CIP), and the addition of a biocide (DBNPA) was studied. Different analytical tools were applied, including Bactiquant, Total Organic Carbon (TOC), Assimilable Organic Carbon (AOC), and Liquid Chromatography for Organic Carbon Detection (LC-OCD). Out results showed that UF did not decrease TOC but it was sufficient in removing up to 99.7% of bacteria. Nanofiltration, removed up to 95% of TOC. However, NF permeate had a high increase in AOC as compared to the raw seawater sample. The LC-OCD results suggested that this might be due to the increased low molecular weight neutrals which were the most common organic species in the NF permeate. The fouling control techniques showed various effects on the desalination efficiency. Daily CEB did not cause a reduction in TOC or bacteria but decreased AOC in the UF filtrate. The biocide addition resulted in an adequate membranes protection from fouling and it did not affect the investigated water parameters. When the dosing of biocide was stopped, the water quality

  8. Ceramic Ultrafiltration of Marine Algal Solutions: A Comprehensive Study

    KAUST Repository

    Dramas, Laure

    2014-09-01

    Algal bloom can significantly impact reverse osmosis desalination process and reduce the drinking water production. In 2008, a major bloom event forced several UAE reverse osmosis plants to stop their production, and in this context, a better understanding of UF membrane fouling caused by algal organic matter (AOM) is needed, in order to adjust the filtration conditions during algal bloom events. Polymeric MF/UF membranes are already widely used for RO pretreatment, but ceramic UF membranes can also be an alternative for the filtration of marine algal solutions. The fouling potential of the Red Sea and the Arabian Sea, sampled at different seasons, along with four algal monocultures grown in laboratory, and one mesocosm experiment in the Red Sea was investigated. Algal solutions induce a stronger and more irreversible fouling than terrestrial humic solution, toward ceramic membrane. During algal bloom events, this fouling is enhanced and becomes even more problematic at the decline phase of the bloom, for a similar initial DOC. Three main mechanisms are involved: the formation of a cake layer at the membrane surface; the penetration of the algal organic matter (AOM) in the pore network of the membrane; the strong adhesion of AOM with the membrane surface. The last mechanism is species-specific and metal-oxide specific. In order to understand the stronger ceramic UF fouling at the decline phase, AOM quality was analyzed every two days. During growth, AOM is getting enriched in High Molecular Weight (HMW) structures (> 200 kDa), which are mainly composed by proteins and polysaccharides, and these compounds seem to be responsible for the stronger fouling at decline phase. In order to prevent the fouling of ceramic membrane, coagulation-flocculation (CF) using ferric chloride was implemented prior to filtration. It permits a high removal of HMW compounds and greatly reduces the fouling potential of the algal solution. During brief algal bloom events, CF should be

  9. An innovative treatment concept for future drinking water production : Fluidized ion exchange – ultrafiltration – nanofiltration – granular activated carbon filtration

    NARCIS (Netherlands)

    Li, S.; Heijman, S.G.J.; Verberk, J.Q.J.C.; Van Dijk, J.C.

    2009-01-01

    A new treatment concept for drinking water production from surface water has been investigated on a pilot scale. The treatment concept consists of fluidized ion exchange (FIEX), ultrafiltration (UF), nanofiltration (NF), and granular activated carbon filtration (GAC). The FIEX process removed

  10. Association of haemodynamic changes measured by serial central venous saturation during ultrafiltration for acutely decompensated heart failure with diuretic resistance and change in renal function.

    Science.gov (United States)

    Vazir, Ali; Simpkin, Victoria L; Marino, Philip; Ludman, Andrew; Banya, Winston; Tavazzi, Guido; Bastin, Anthony J; Trenfield, Sarah; Ghori, Arshad; Alexander, Peter D; Griffiths, Mark; Price, Susanna; Sharma, Rakesh; Cowie, Martin R

    2016-10-01

    Patients with acute decompensated heart failure with diuretic resistance (ADHF-DR) have a poor prognosis. The aim of this study was to assess in patients with ADHF-DR, whether haemodynamic changes during ultrafiltration (UF) are associated with changes in renal function (Δcreatinine) and whether Δcreatinine post UF is associated with mortality. Seventeen patients with ADHF-DR underwent 20 treatments with UF. Serial bloods (4-6 hourly) from the onset of UF treatment were measured for renal function, electrolytes and central venous saturation (CVO2). Univariate and multivariate analysis were performed to assess the relationship between changes in markers of haemodynamics [heart rate (HR), systolic blood pressure (SBP), packed cell volume (PCV) and CVO2] and Δcreatinine. Patients were followed up and mortality recorded. Cox-regression survival analysis was performed to determine covariates associated with mortality. Renal function worsened after UF in 17 of the 20 UF treatments (baseline vs. post UF creatinine: 164±58 vs. 185±69μmol/l, Pchanges in SBP, HR and PCV [Pchanges during UF as measured by the surrogate of cardiac output was associated with Δcreatinine. Worsening renal function at end of UF treatment occurred in the majority of patients and was associated with mortality. Copyright © 2016. Published by Elsevier Ireland Ltd.

  11. Analysis of accidental UF6 releases

    International Nuclear Information System (INIS)

    Fan Yumao; Tan Rui; Gao Qifa

    2012-01-01

    As interim substance in the nuclear fuel enrichment process, Uranium Hexafluoride (UF 6 ) is widely applied in nuclear processing, enrichment and fuel fabrication plants. Because of its vivid chemical characteristics and special radiological hazard and chemical toxicity, great attention must be paid to accident of UF 6 leakage. The chemical reactions involved in UF 6 release processes were introduced, therewith potential release styles, pathways and characteristics of diffusion were analyzed. The results indicated that the accidental release process of UF 6 is not a simple passive diffusion. So, specific atmospheric diffusion model related to UF 6 releases need be used in order to analyze and evaluate accurately the accidental consequences. (authors)

  12. Pilot plant UF6 to UF4 test operations report

    International Nuclear Information System (INIS)

    Bicha, W.J.; Fallings, M.; Gilbert, D.D.; Koch, G.E.; Levine, P.J.; McLaughlin, D.F.; Nuhfer, K.R.; Reese, J.C.

    1987-02-01

    The FMPC site includes a plant designed for the reduction of uranium hexafluoride (UF 6 ) to uranium tetrafluoride (UF 4 ). Limited operation of the upgraded reduction facility began in August 1984 and continued through January 19, 1986. A reaction vessel ruptured on that date causing the plant operation to be shut down. The DOE conducted a Class B investigation with the findings of the investigation board issued in preliminary form in May 1986 and as a final recommendation in July 1986. A two-phase restart of the plant was planned and implemented. Phase I included implementing safety system modifications, changing reaction vessel temperature control strategy, and operating the reduction plant under an 8-week controlled test. The results of the test period are the subject of this report. 41 figs., 11 tabs

  13. Understanding the risk of scaling and fouling in hollow fiber forward osmosis membrane application

    KAUST Repository

    Majeed, Tahir; Phuntsho, Sherub; Jeong, Sanghyun; Zhao, Yanxia; Gao, Baoyu; Shon, Ho Kyong

    2016-01-01

    Fouling studies of forward osmosis (FO) were mostly conducted based on fouling evaluation principals applied to pressure membrane processes such as reverse osmosis (RO)/nanofiltration (NF)/microfiltration (MF)/ultrafiltration (UF). For RO/NF/MF/UF processes, the single flux driving force (hydraulic pressure) remains constant, thus the fouling effect is easily evaluated by comparing flux data with the baseline. Whilst, the scenario of fouling effects for FO process is entirely different from RO/NF/MF/UF processes. Continuously changing driving force (osmotic pressure difference), the changes in concentration polarization associated with the varying draw solution/feed solution concentration and the fouling layer effects collectively influence the FO flux. Thus, usual comparison of the FO flux outcome with the baseline results can not exactly indicate the real affect of membrane fouling, rather presents a misleading cumulative effect. This study compares the existing FO fouling technique with an alternate fouling evaluation approach using two FO set-ups. Scaling and fouling risk for hollow fiber FO was separately investigated using synthetic water samples and model organic foulants as alginate, humic acid and bovine serum albumin. Results indicated that FO flux declines up to 5% and 49% in active layer-feed solution and active layer-draw solution orientations respectively.

  14. Understanding the risk of scaling and fouling in hollow fiber forward osmosis membrane application

    KAUST Repository

    Majeed, Tahir

    2016-06-23

    Fouling studies of forward osmosis (FO) were mostly conducted based on fouling evaluation principals applied to pressure membrane processes such as reverse osmosis (RO)/nanofiltration (NF)/microfiltration (MF)/ultrafiltration (UF). For RO/NF/MF/UF processes, the single flux driving force (hydraulic pressure) remains constant, thus the fouling effect is easily evaluated by comparing flux data with the baseline. Whilst, the scenario of fouling effects for FO process is entirely different from RO/NF/MF/UF processes. Continuously changing driving force (osmotic pressure difference), the changes in concentration polarization associated with the varying draw solution/feed solution concentration and the fouling layer effects collectively influence the FO flux. Thus, usual comparison of the FO flux outcome with the baseline results can not exactly indicate the real affect of membrane fouling, rather presents a misleading cumulative effect. This study compares the existing FO fouling technique with an alternate fouling evaluation approach using two FO set-ups. Scaling and fouling risk for hollow fiber FO was separately investigated using synthetic water samples and model organic foulants as alginate, humic acid and bovine serum albumin. Results indicated that FO flux declines up to 5% and 49% in active layer-feed solution and active layer-draw solution orientations respectively.

  15. A simplified ultrafiltration method for determination of serum free cortisol

    International Nuclear Information System (INIS)

    MacMahon, W.; Sgoutas, D.

    1983-01-01

    The authors describe the suitability of the Amicon MPS-1 centrifugal ultrafiltration device and the YMB membrane for measuring free cortisol in serum. The method combines two independent assays: total cortisol and the ultrafiltrate fraction of added [ 3 H]cortisol. The unbound fraction is determined in 0.25-0.30 ml of ultrafiltrate collected from 0.6 to 1 ml of serum that has been equilibrated with [ 3 H]cortisol at 37 0 C for 20 min. The assay is rapid (less than 1 h), practical (no more than 0.6 ml of serum is necessary) and repeatable (CV: 3.8% within-assay and 12.2% in different assays). Error introduced in free cortisol measurement due to dilution effects in dialysis is systematically defined, and the effect of tracer purity on the ultrafiltration method is examined. Dialyzed sera from normal men and women, from patients with Cushing's disease and adrenal insufficiency, and from pregnant women gave ultrafiltration results that accurately duplicated those obtained by previous dialysis. (Auth.)

  16. Effect of interactions between Co(2+) and surface goethite layer on the performance of α-FeOOH coated hollow fiber ceramic ultrafiltration membranes.

    Science.gov (United States)

    Zhu, Zhiwen; Zhu, Li; Li, Jianrong; Tang, Jianfeng; Li, Gang; Hsieh, Yi-Kong; Wang, TsingHai; Wang, Chu-Fang

    2016-03-15

    The consideration of water energy nexus inspires the environmental engineering community to pursue a more sustainable strategy in the wastewater treatment. One potential response would be to enhance the performance of the low-pressure driven filtration system. To reach this objective, it is essential to have a better understanding regarding the surface interaction between the target substance and the surface of membrane. In this study, the hollow fiber ceramic membranes were coated with a goethite layer in order to enhance the Co(2+) rejection. Experimental results indicate that higher Co(2+) rejections are always accompanied with the significant reduction in the permeability. Based on the consideration of electroviscous effect, the surface interactions including the induced changes in viscosity, pore radius and Donnan effect in the goethite layer are likely responsible for the pH dependent behaviors in the rejection and permeability. These results could be valuable references to develop the filtration system with high rejection along with acceptable degree of permeability in the future. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. New method for exopolysaccharide determination in culture broth using stirred ultrafiltration cells.

    Science.gov (United States)

    Bergmaier, D; Lacroix, C; Guadalupe Macedo, M; Champagne, C P

    2001-10-01

    A new method to remove simple carbohydrates from culture broth prior to the quantification of exopolysaccharides (EPS) was developed and validated for the EPS-producing strain, Lactobacillus rhamnosus RW-9595M. This method uses ultrafiltration (UF) in stirred cells followed by polysaccharide detection in the retentate by the phenol-sulfuric acid method. The UF method was compared with a conventional method based on ethanol extraction, dialysis, protein removal by trichloroacetic acid (TCA) and freeze-drying. EPS production during pH-controlled batch fermentations in basal minimum medium, whey permeate (WP). and whey permeate supplemented with yeast extract, minerals and Tween-80 (SWP) was determined by the new UF and conventional methods. EPS recovery by the new method ranged from 83% to 104% for EPS added in the concentration range 40-1,500 mg/l in 0.1 M NaCl solution or culture medium. The UF method was rapid (8 h), accurate and simple, and required only a small sample volume (1-5 ml). A very high maximum EPS production was measured in SWP by both the UF and conventional methods (1,718 and 1,755 mg/l).

  18. Sucrose purification and repeated ethanol production from sugars remaining in sweet sorghum juice subjected to a membrane separation process.

    Science.gov (United States)

    Sasaki, Kengo; Tsuge, Yota; Kawaguchi, Hideo; Yasukawa, Masahiro; Sasaki, Daisuke; Sazuka, Takashi; Kamio, Eiji; Ogino, Chiaki; Matsuyama, Hideto; Kondo, Akihiko

    2017-08-01

    The juice from sweet sorghum cultivar SIL-05 (harvested at physiological maturity) was extracted, and the component sucrose and reducing sugars (such as glucose and fructose) were subjected to a membrane separation process to purify the sucrose for subsequent sugar refining and to obtain a feedstock for repeated bioethanol production. Nanofiltration (NF) of an ultrafiltration (UF) permeate using an NTR-7450 membrane (Nitto Denko Corporation, Osaka, Japan) concentrated the juice and produced a sucrose-rich fraction (143.2 g L -1 sucrose, 8.5 g L -1 glucose, and 4.5 g L -1 fructose). In addition, the above NF permeate was concentrated using an ESNA3 NF membrane to provide concentrated permeated sugars (227.9 g L -1 ) and capture various amino acids in the juice, enabling subsequent ethanol fermentation without the addition of an exogenous nitrogen source. Sequential batch fermentation using the ESNA3 membrane concentrate provided an ethanol titer and theoretical ethanol yield of 102.5-109.5 g L -1 and 84.4-89.6%, respectively, throughout the five-cycle batch fermentation by Saccharomyces cerevisiae BY4741. Our results demonstrate that a membrane process using UF and two types of NF membranes has the potential to allow sucrose purification and repeated bioethanol production.

  19. Water hammer reduces fouling during natural water ultrafiltration.

    Science.gov (United States)

    Broens, F; Menne, D; Pothof, I; Blankert, B; Roesink, H D W; Futselaar, H; Lammertink, R G H; Wessling, M

    2012-03-15

    Today's ultrafiltration processes use permeate flow reversal to remove fouling deposits on the feed side of ultrafiltration membranes. We report an as effective method: the opening and rapid closing of a valve on the permeate side of an ultrafiltration module. The sudden valve closure generates pressure fluctuations due to fluid inertia and is commonly known as "water hammer". Surface water was filtrated in hollow fiber ultrafiltration membranes with a small (5%) crossflow. Filtration experiments above sustainable flux levels (>125 l (m2h)(-1)) show that a periodic closure of a valve on the permeate side improves filtration performance as a consequence of reduced fouling. It was shown that this effect depends on flux and actuation frequency of the valve. The time period that the valve was closed proved to have no effect on filtration performance. The pressure fluctuations generated by the sudden stop in fluid motion due to the valve closure are responsible for the effect of fouling reduction. High frequency recording of the dynamic pressure evolution shows water hammer related pressure fluctuations to occur in the order of 0.1 bar. The pressure fluctuations were higher at higher fluxes (higher velocities) which is in agreement with the theory. They were also more effective at higher fluxes with respect to fouling mitigation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Membrane technology for sustainable treated wastewater reuse: agricultural, environmental and hydrological considerations.

    Science.gov (United States)

    Oron, Gideon; Gillerman, Leonid; Bick, Amos; Manor, Yossi; Buriakovsky, Nisan; Hagin, Joseph

    2008-01-01

    Field experiments were conducted in agricultural fields in which secondary wastewater of the City of Arad (Israel) is reused for irrigation. For sustainable agricultural production and safe groundwater recharge the secondary effluent is further polished by a combined two-stage membrane pilot system. The pilot membrane system consists of two main in row stages: Ultrafiltration (UF) and Reverse Osmosis (RO). The UF stage is efficient in the removal of the pathogens and suspended organic matter while the successive RO stage provides safe removal of the dissolved solids (salinity). Effluents of various qualities were applied for agricultural irrigation along with continuous monitoring of the membrane system performance. Best agricultural yields were obtained when applying effluent having minimal content of dissolved solids (after the RO stage) as compared with secondary effluent without any further treatment and extended storage. In regions with shallow groundwater reduced soil salinity in the upper productive layers, maintained by extra membrane treatment, will guarantee minimal dissolved solids migration to the aquifers and minimize salinisation processes. (c) IWA Publishing 2008.

  1. Metals, heavy metals and microorganism removal from spent filter backwash water by hybrid coagulation-UF processes

    Directory of Open Access Journals (Sweden)

    Mokhtar Mahdavi

    2018-04-01

    Full Text Available Spent filter backwash water (SFBW reuse has attracted particular attention, especially in countries that experience water scarcity. It can act as a permanent water source until the water treatment plant is working. In this study, the concentrations of Fe, Al, Pb, As, and Cd with total and fecal coliform (TC/FC were investigated in raw and treated SFBW by hybrid coagulation-UF processes. The pilot plant consisted of pre-sedimentation, coagulation, flocculation, clarification, and ultrafiltration (UF units. Poly-aluminum ferric chloride (PAFCL and ferric chloride (FeCl3 were used as pretreatment. The results showed that, at the optimum dose of PAFCl, the average removal of TC and FC was 88 and 79% and with PAFCl-UF process, it reached 100 and 100%, respectively. For FeCl3, removal efficiency of TC and FC were 81 and 72% and by applying FeCl3-UF process, it reached 100 and 100%, respectively. In comparison with FeCl3, PAFCl showed better removal efficiency for Fe, Pb, As, and Cd, except residual Al concentration. Coagulation-UF process could treat SFBW efficiently and treated SFBW could meet the US-EPA drinking water standard. Health risk index values of Fe, AL, Pb, AS, and Cd in treated SFBW indicate no risk of exposure to the use of this water.

  2. Performance evaluation of tertiary treatment through ultrafiltration: Case study in Isfahan-industrial wastewater treatment plant

    Directory of Open Access Journals (Sweden)

    Abbas Khodabakhshi

    2015-01-01

    Conclusion: UF was able to improve chemical parameters of secondary effluent and meet national environmental standards. However, achievement to optimum operation of this system requires adequate pretreatments such as adding filter aid, sand filtration and GAC. The most part of suspended particles expressed by turbidity was removed within UF membrane, whereas only a little of organic substance expressed by COD or color and salt expressed by conductivity could be removed.

  3. Enhanced antifouling and antibacterial properties of poly (ether sulfone) membrane modified through blending with sulfonated poly (aryl ether sulfone) and copper nanoparticles

    Science.gov (United States)

    Zhang, Jingjing; Xu, Ya'nan; Chen, Shouwen; Li, Jiansheng; Han, Weiqing; Sun, Xiuyun; Wu, Dihua; Hu, Zhaoxia; Wang, Lianjun

    2018-03-01

    A series of novel blend ultrafiltration (UF) membranes have been successfully prepared from commercial poly (ether sulfone), lab-synthesized sulfonated poly (aryl ether sulfone) (SPAES, 1 wt%) and copper nanoparticles (0 ∼ 0.4 wt%) via immersion precipitation phase conversion. The micro-structure and separation performance of the membranes were characterized by field emission scanning electron microscopy (SEM) and cross-flow filtration experiments, respectively. Sodium alginate, bovine serum albumin and humic acid were chosen as model organic foulants to investigate the antifouling properties, while E. coil was used to evaluate the antibacterial property of the fabricated membranes. By the incorporation with SPAES and copper nanoparticles, the hydrophilicity, antifouling and antibacterial properties of the modified UF membranes have been profoundly improved. At a copper nanoparticles content of 0.4 wt%, the PES/SPAES/nCu(0.4) membrane exhibited a high pure water flux of 193.0 kg/m2 h, reaching the smallest contact angle of 52°, highest flux recovery ratio of 79% and largest antibacterial rate of 78.9%. Furthermore, the stability of copper nanoparticles inside the membrane matrix was also considerably enhanced, the copper nanoparticles were less than 0.08 mg/L in the effluent during the whole operation.

  4. Application of membrane technologies for the treatment of textile wastewater and synthetic textile dyes

    International Nuclear Information System (INIS)

    Aouni, A.; Bes-Pia, A.; Fersi, C.; Dhahbi, M.; Cuartas-Uribe, B.; Alcaina-Miranda, M. I.

    2009-01-01

    Textile industry is characterized by using a great variety of chemicals and by large water consumption. In this way, textile effluents contains many types of dyes, detergents, solvents and salts depending on the particular textile mill processes (dyeing, printing, finishing...) and on the raw matter. For those reasons, textile industry is one of the main sources of industrial pollution, producing effluents discharges characterized by high conductivities and chemical oxygen demand (COD) values and strong colour. Process selection and operating conditions are important issues to optimize technically and economically the textile effluent treatment. This work presents the results of the laboratory-scale membrane experiments of textile industry effluents and synthetic textile dyes. Different types of Ultrafiltration (UF) and Nano filtration (NF) membranes were evaluated for permeate flux and their suitability in separating COD, colour, conductivity. Experiments demonstrated that membrane treatment is a very promising advanced treatment option for pollution control for textile industry effluents. The results of this work show that the direct ultrafiltration seems to be a realistic method in the pretreatment of the textile wastewater. In fact, NF process was successfully used to improve permeate quality of synthetic dyeing textile wastewater, but this process presented some limitations in the treatment of textile industry effluents because of membrane fouling problems. So, this process requires an efficient and appropriate technique such as ultrafiltration as a pre-treatment step for textile wastewater reuse. For direct nano filtration of synthetic textile dyes aqueous solutions, with a weak salt concentration (500 ppm), good results were obtained. More than 95 pour cent of color was removed from the treated water accompanied with a reduction of 92 pour cent of conductivity and COD. Based on the experiments; NF membranes are suitable for producing permeate of reusable

  5. Treatment of simulated plutonium-containing wastewater by ultrafiltration-reverse osmosis technology

    International Nuclear Information System (INIS)

    Xiong Zhonghua; Fan Xianhua; Luo Deli; Wang Tuo; Chen Qi

    2008-01-01

    Ultrafiltration and reverse osmosis were employed for the treatment of low level radioactive water containing plutonium. The system consists of ultrafiltration module with hollow fibre membrane and reverse osmosis module with spiral membrane. The decontamination efficiency and volume concentration ratio affected by technical parameters were explored in the experiment. The results show that the decontamination efficiency achieves 99.94% and the volume concentration ratio achieves 12.5 at pH=10 for solution fed into the membrane separation system. This technology will be applied in radioactive waste minimization as a new treatment method. (authors)

  6. An improved ultrafiltration method for determining free testosterone in serum

    International Nuclear Information System (INIS)

    Vlahos, I.; MacMahon, W.; Sgoutas, D.; Bowers, W.; Thompson, J.; Trawick, W.

    1982-01-01

    In this method, we use the Amicon MPS-1 centrifugal ultrafiltration device and the YMB membrane in measuring free testosterone in serum. Two independent assays are combined: total testosterone and the ultrafiltrable fraction of added [ 3 H]testosterone. The unbound fraction is determined in 0.15-0.5 mL ultrafiltrates of 0.6 to 1 mL of variably diluted serum that has been equilibrated with [ 3 H]testosterone at 37 degrees C. The assay is rapid (less than 1 h), practicable (requires 0.6 mL of serum), and reproducible (CV 3.2% within assay, 3.9% between assays). Accuracy was evaluated as the fraction of free testosterone in the ultrafiltrate of dialyzed serum vs that in a prior dialysate; they were the same confirming the validity of the free testosterone measurement. Samples from ostensibly healthy men and women and from hirsute and pregnant women gave results that agreed with those obtained by equilibrium dialysis. Total testosterone concentrations for normal and hirsute women showed considerable overlap, but data on free testosterone concentrations in these populations were better resolved

  7. Cleaning efficiency enhancement by ultrasounds for membranes used in dairy industries.

    Science.gov (United States)

    Luján-Facundo, M J; Mendoza-Roca, J A; Cuartas-Uribe, B; Álvarez-Blanco, S

    2016-11-01

    Membrane cleaning is a key point for the implementation of membrane technologies in the dairy industry for proteins concentration. In this study, four ultrafiltration (UF) membranes with different molecular weight cut-offs (MWCOs) (5, 15, 30 and 50kDa) and materials (polyethersulfone and ceramics) were fouled with three different whey model solutions: bovine serum albumin (BSA), BSA plus CaCl2 and whey protein concentrate solution (Renylat 45). The purpose of the study was to evaluate the effect of ultrasounds (US) on the membrane cleaning efficiency. The influence of ultrasonic frequency and the US application modes (submerging the membrane module inside the US bath or applying US to the cleaning solution) were also evaluated. The experiments were performed in a laboratory plant which included the US equipment and the possibility of using two membrane modules (flat sheet and tubular). The fouling solution that caused the highest fouling degree for all the membranes was Renylat 45. Results demonstrated that membrane cleaning with US was effective and this effectiveness increased at lower frequencies. Although no significant differences were observed between the two different US applications modes tested, slightly higher cleaning efficiencies values placing the membrane module at the bottom of the tank were achieved. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Preparation and Characterization of Polymeric-Hybrid PES/TiO2 Hollow Fiber Membranes for Potential Applications in Water Treatment

    Directory of Open Access Journals (Sweden)

    Silvia Simone

    2017-04-01

    Full Text Available In this work, poly(ethersulfone (PES ultrafiltration (UF hollow fibers (HF were modified by introducing TiO2 nanoparticles (TiO2-NPs in the polymeric dope, to endow them with photocatalytic properties. Different dope compositions and spinning conditions for producing “blank” PES UF fibers with suitable properties were investigated. PEO–PPO–PEO (Poly(ethylene glycol-block-poly(propylene glycol-block-poly(ethylene glycol, Pluronic® (Sigma-Aldrich, Milan, Italy was finally selected as the additive and a suitable dope composition was identified. After the detection of an appropriate dope composition and the optimization of the spinning parameters, PES-TiO2 HF was produced. The optimized composition was employed for preparing the mixed matrix HF loaded with TiO2 NPs. The effect of different TiO2 NP (0.3–1 wt % concentrations and bore fluid compositions on the fiber morphology and properties were explored. The morphology of the produced fibers was analyzed by Scanning Electron Microscopy (SEM. Fibers were further characterized by measuring: pore size diameters and thickness, porosity, and pure water permeability (PWP. The photocatalytic activity of the new membranes was also tested by UV light irradiation. The model “foulant” methylene blue (MB was used in order to prove the efficiency of the novel UF membrane for dye photo-degradation.

  9. Non-aqueous retention measurement: ultrafiltration behaviour of polystyrene solutions and colloidal silver particles

    NARCIS (Netherlands)

    Beerlage, M.A.M.; Beerlage, M.A.M.; Heijnen, M.L.; Mulder, M.H.V.; Smolders, C.A.; Smolders, C.A.; Strathmann, H.

    1996-01-01

    The retention behaviour of polyimide ultrafiltration membranes was investigated using dilute solutions of polystyrene in ethyl acetate as test solutions. It is shown that flow-induced deformation of the polystyrene chains highly affects the membrane retention. This coil-stretch transition is not

  10. A study of UF4 preparations

    International Nuclear Information System (INIS)

    Chang, I.S.; Doh, J.B.; Choi, Y.D.

    1985-05-01

    Uranium tetrafluoride (UF 4 ), green salt, is very important intermediate in the production of metallic uranium and uranium hexafluoride (UF 6 ) for enrichment. The hydrofluorination of uranium dioxide (UO 2 ) with anhydrous hydrogen fluoride (HF), produced from ADU (ammonium diuranate) process or AUC (ammonium uranyl carbonate) process, are commercially used for the production of uranium tetrafluoride. At present, a new approach such as direct UF 4 preparation at the mine-site without further precipitation, filteration and drying of yellow cake from leaching solution has been studied. The single step continous reduction of uranium hexafluoride to uranium tetrafluoride is one of the most interesting process being applied for the commercial use of a large amount of depleted UF 6 which is produced in tail after enrichment. The direct conversion of UF 6 and UF 4 with hydrogen and fluorine gases using cold wall reactor has a certain advantage over various wet process such as AUD and AUC processes in which hydrolysis of UF 6 and various kind of chemicals are required, including liquid waste treatment. This report reviews and analyzes the theory and processes being used commercially or under study. (Author)

  11. Key process parameters involved in the treatment of olive mill wastewater by membrane bioreactor.

    Science.gov (United States)

    Jaouad, Y; Villain-Gambier, M; Mandi, L; Marrot, B; Ouazzani, N

    2018-04-18

    The Olive Mill Wastewater (OMWW) biodegradation in an external ceramic membrane bioreactor (MBR) was investigated with a starting acclimation step with a Ultrafiltration (UF) membrane (150 kDa) and no sludge discharge in order to develop a specific biomass adapted to OMWW biodegradation. After acclimation step, UF was replaced by an Microfiltration (MF) membrane (0.1 µm). Sludge Retention Time (SRT) was set around 25 days and Food to Microorganisms ratio (F/M) was fixed at 0.2 kg COD  kg MLVSS -1  d -1 . At stable state, removal of the main phenolic compounds (hydroxytyrosol and tyrosol) and Chemical Oxygen Demand (COD) were successfully reached (95% both). Considered as a predominant fouling factor, but never quantified in MBR treated OMWW, Soluble Microbial Products (SMP) proteins, polysaccharides and humic substances concentrations were determined (80, 110 and 360 mg L -1 respectively). At the same time, fouling was easily managed due to favourable hydraulic conditions of external ceramic MBR. Therefore, OMWW could be efficiently and durably treated by an MF MBR process under adapted operating parameters.

  12. Improved separation and antifouling properties of thin-film composite nanofiltration membrane by the incorporation of cGO

    Science.gov (United States)

    Li, Hongbin; Shi, Wenying; Du, Qiyun; Zhou, Rong; Zhang, Haixia; Qin, Xiaohong

    2017-06-01

    Poly(piperazine amide) composite nanofiltration (NF) membranes were modified through the incorporation of carboxylated graphene oxide (cGO) in the polyamide layer during the interfacial polymerization (IP) process on the polysulfone (PSF)/nonwoven fabric (NWF) ultrafiltration (UF) substrate membrane surface. The composition and morphology of the prepared NF membrane surface were determined by means of ATR-FTIR, SEM-EDX and AFM. The effects of cGO contents on membrane hydrophilicity, separation performance and antifouling properties were investigated through Water Contact Angle (WCA) analysis, the permeance and three-cycle fouling measurements. The growth model of cGO-incorporated polyamide thin-film was proposed. Compared to the original NF membranes, the surface hydrophilicity, water permeability, salt rejection and antifouling properties of the cGO-incorporated NF membrane had all improved. When cGO content was 100 ppm, the MgSO4 rejection of composite NF membrane reached a maximum value of 99.2% meanwhile membrane obtained an obvious enhanced water flux (81.6 L m-2 h-1, at 0.7 MPa) which was nearly three times compared to the virginal NF membrane. The cGO-incorporated NF membrane showed an excellent selectivity of MgSO4 and NaCl with the rejection ratio of MgSO4/NaCl of approximately 8.0.

  13. Functionalized membranes for environmental remediation and selective separation

    Science.gov (United States)

    Xiao, Li

    Membrane process including microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) have provided numerous successful applications ranging from drinking water purification, wastewater treatment, to material recovery. The addition of functional moiety in the membranes pores allows such membranes to be used in challenging areas including tunable separations, toxic metal capture, and catalysis. In this work, polyvinylidene fluoride (PVDF) MF membrane was functionalized with temperature responsive (poly(N-isopropylacrylamide), PNIPAAm) and pH responsive (polyacrylic acid, PAA) polymers. It's revealed that the permeation of various molecules (water, salt and dextran) through the membrane can be thermally or pH controlled. The introduction of PAA as a polyelectrolyte offers an excellent platform for the immobilization of metal nanoparticles (NPs) applied for degradation of toxic chlorinated organics with significantly increased longevity and stability. The advantage of using temperature and pH responsive polymers/hydrogels also includes the high reactivity and effectiveness in dechlorination. Further advancement on the PVDF functionalization involved the alkaline treatment to create partially defluorinated membrane (Def-PVDF) with conjugated double bounds allowing for the covalent attachment of different polymers. The PAA-Def-PVDF membrane shows pH responsive behavior on both the hydraulic permeability and solute retention. The sponge-like PVDF (SPVDF) membranes by phase inversion were developed through casting PVDF solution on polyester backing. The SPVDF membrane was demonstrated to have 4 times more surface area than commercial PVDF MF membrane, allowing for enhanced nanoparticles loading for chloro-organics degradation. The advanced functionalization method and process were also validated to be able to be scaled-up through the evaluation of full-scale functionalized membrane provided by Ultura Inc. California, USA. Nanofiltration (NF

  14. Optimization of O3 as Pre-Treatment and Chemical Enhanced Backwashing in UF and MF Ceramic Membranes for the Treatment of Secondary Wastewater Effluent and Red Sea Water

    KAUST Repository

    Herrera, Catalina

    2011-01-01

    Ceramic membranes have proven to have many advantages over polymeric membranes. Some of these advantages are: resistance against extreme pH, higher permeate flux, less frequent chemical cleaning, excellent backwash efficiency and longer lifetime

  15. Concentration of lemon pectin extract by ultrafiltration

    Directory of Open Access Journals (Sweden)

    Damián Stechina

    2012-09-01

    Full Text Available Current annual lemon production in Argentina is about 900 thousand t. 75% is used industrially to obtain pasteurized juice concentrate. Since 40 - 45 % of citrus fruit content is peel and seeds, the annual lemon residue yield is 360 thousand t. Lemon peel contains about 30% (B.S. of peptic substances with an important commercial value due to its gelling and thickening properties for food, chemical, pharmacological and cosmetic products. Membrane processes have many applications in food manufacture. The objective of this study is to analyze the influence of ultrafiltration operating variables on instant permeate flow (Fp and on the energy requirement for pectin extract concentration from lemon peel. A DDS lab module was used, lab 20-772 model with synthetic material membranes, 9 kDa, shear force, the intrinsic membrane resistance (Rm being 3*1013 m -1 . Results show that Fp decrease caused by polarization induced resistance occurrence and the influence of operating variables on Fp offer relevant data to estimate the energy requirement in relation to feeding flow at constant temperature, which may be compared to pectin concentration increase in the retained flow in relation to initial extract concentration.

  16. Sensitivity of UF-R, UF-VCh, UF-VR films used for soft x-ray (lambda=2+10A) detection

    International Nuclear Information System (INIS)

    Aglitskij, E.V.; Bojko, V.A.; Kalinkina, T.A.

    1975-01-01

    The sensitometric characteristics of the following types of photographic film were measured in the range of wavelengths 2-10A: UF-R, UF-VCh, and UF-VR. It was demonstrated that UF-VR photographic film is four times as sensitive as UF-R film and 1.6 times as sensitive as UF-VCh film; it is also most suitable film for x-ray spectroscopy of multiply charged ions and for diagnosing high-temperature laser plasma

  17. Operating considerations of ultrafiltration in enzyme enhanced carbon capture

    DEFF Research Database (Denmark)

    Deslauriers, Maria Gundersen; Gladis, Arne; Fosbøl, Philip Loldrup

    2017-01-01

    capture capacity of 1 MTonn CO2/year, and is here operated for one year continuously. This publication compares soluble enzymes dissolved in a capture solvent with and without the use of ultrafiltration membranes. The membranes used here have an enzyme retention of 90%, 99% and 99.9%. Enzyme retention......Today, enzyme enhanced carbon capture and storage (CCS) is gaining interest, since it can enable the use of energy efficient solvents, and thus potentially reduce the carbon footprint of CCS. However, a limitation of this technology is the high temperatures encountered in the stripper column, which...

  18. The effect of ultrafiltration with cardiopulmonary bypass on the removal of dabigatran from the circulation of adult pigs.

    Science.gov (United States)

    DeNino, Walter F; Carter, Christopher B; Sievert, Alicia; Goss, Ashley; Toole, John M; Mukherjee, Rupak; Uber, Walter E

    2016-07-01

    Dabigatran etexilate is a direct thrombin inhibitor approved for use in patients with non-valvular atrial fibrillation. There is no currently available pharmacological therapy to reverse this renally cleared anticoagulant. Dabigatran has a low level of plasma protein binding and has been considered dialyzable. We used a pig model with renal artery ligation to exclude intrinsic drug excretion to examine the efficacy of ultrafiltration (UF) during cardiopulmonary bypass (CPB) for dabigatran removal. Dabigatran was intravenously infused (20 mg) in Yorkshire pigs (male, n=7, 70±1 kg) following renal artery ligation. CPB with UF was initiated after heparinization and continued until a total volume of 6 liters of UF effluent was removed. Serial labs, including dabigatran concentration, activated coagulation times (ACT), hematocrit and creatinine were drawn at intervals before the start of CPB and then incrementally during UF (0, 2, 4 and 6 L removed). Hemodialysis (HD) was performed on one animal following UF. Dabigatran concentration (ng/mL) rose from undetectable levels at baseline to 296±70 (p<0.05) at the conclusion of infusion, but dropped significantly upon administration of heparin (178±40, p<0.05). A further decrement in dabigatran concentration was observed from the administration of heparin to the start of CPB (to 135±28, p<0.05). Once on CPB, dabigatran remained stable, with the end UF (eUF) dabigatran concentration being 133±34. Dabigatran concentration in the UF effluent was measured in one animal and was 98.8, with 6 L of effluent having been removed. The total recovery of dabigatran was calculated to be less than 5%. Dabigatran concentrations also did not decrease appreciably with HD on CPB following UF. UF in conjunction with CPB was ineffective at removing dabigatran. Heparin demonstrated a dabigatran-lowering effect, suggesting a possible drug interaction or assay impairment. Based on these findings, emergent cardiac surgery with UF on

  19. Fouling reduction by ozone-enhanced backwashing process in ultrafiltration of petroleum-based oil in water emulsion

    Science.gov (United States)

    Aryanti, Nita; Prihatiningtyas, Indah; Kusworo, Tutuk Djoko

    2017-06-01

    Ultrafiltration membrane has been successfully applied for oily waste water treatment. However, one significant drawback of membrane technology is fouling which is responsible for permeate flux decline as well as reducing membrane performance. One method commonly used to reduce fouling is a backwashing process. The backwashing is carried out by a push of reversed flow from permeate side to the feed side of a membrane to remove fouling on the membrane pore and release fouling release fouling layer on the external side. However, for adsorptive fouling, the backwashing process was not effective. On the other hand, Ozone demonstrated great performance for reducing organics fouling. Hence this research was focused on backwashing process with ozone for removing fouling due to ultrafiltration of petroleum based oil emulsion. Gasoline and diesel oil were selected as dispersed phase, while as continuous phase was water added with Tween 80 as a surfactant. This research found that the Ozone backwashing was effective to improve flux recovery. In ultrafiltration of gasoline emulsion, the flux recovery after Ozone backwashing was in the range of 42-74%. For ultrafiltration of diesel oil emulsion, the permeate flux recovery was about 35-84%. In addition, foulant deposition was proposed and predicting that foulant deposition for ultrafiltration of gasoline-in-water emulsion was surfactant as the top layer and the oil was underneath the surfactant. On the other hand, for ultrafiltration of diesel oil-in-water emulsion, the oil was predicted as a top layer above the surfactant foulant.

  20. Selective separation of Eu3+ using polymer-enhanced ultrafiltration

    International Nuclear Information System (INIS)

    Norton, M.V.

    1994-03-01

    A process to selectively remove 241 Am from liquid radioactive waste was investigated as an actinide separation method applicable to Hanford and other waste sites. The experimental procedures involved removal of Eu, a nonradioactive surrogate for Am, from aqueous solutions at pH 5 using organic polymers in conjunction with ultrafiltration. Commercially available polyacrylic acid (60,000 MW) and Pacific Northwest Laboratory's (PNL) synthesized E3 copolymer (∼10,000 MW) were tested. Test solutions containing 10 μg/mL of Eu were dosed vath each polymer at various concentrations in order to bind Eu (i.e., by complexation and/or cation exchange) for subsequent rejection by an ultrafiltration coupon. Test solutions were filtered with and without polymer to determine if enhanced Eu separation could be achieved from polymer treatment. Both polymers significantly increased Eu removal. Optimum concentrations were 20 μg/mL of polyacrylic acid and 100 μg/mL of E3 for 100% Eu rejection by the Amicon PM10 membrane at 55 psi. In addition to enhancement of removal, the polymers selectively bound Eu over Na, suggesting that selective separation of Eu was possible. This suggests that polymer-enhanced ultrafiltration is a potential process for separation of 241 Am from Hanford tank waste, further investigation of binding agents and membranes effective under very alkaline and high ionic strength is warranted. This process also has potential applications for selective separation of toxic metals from industrial process streams

  1. Enhanced biofouling resistance of polyethersulfone membrane surface modified with capsaicin derivative and itaconic acid

    International Nuclear Information System (INIS)

    Wang, Jian; Gao, Xueli; Wang, Qun; Sun, Haijing; Wang, Xiaojuan; Gao, Congjie

    2015-01-01

    Graphical abstract: - Highlights: • PES membrane was modified with a capsaicin derivative. • UV-assisted graft polymerization was carried out on membrane surface. • The capsaicin derivative modified membrane shows better antibiofouling property. - Abstract: The culprit of biofouling is the reproduction of viable microorganisms on the membrane surface. Recently, functionalization of membrane surface with natural antibacterial agents has drawn great attention. This work presents the fabrication of antibiofouling polyethersulfone (PES) ultrafiltration (UF) membranes by UV-assisted photo grafting of capsaicin derivative (N-(4-hydroxy-3-methoxy-benzyl)-acrylamide, HMBA) and itaconic acid (IA) on the surface of PES membrane. Results of FTIR-ATR, water static contact angle (WSCA) and atomic force microscopy (AFM) analysis confirmed the successful grafting of HMBA and IA on the membrane surface. We investigated the antifouling and antibacterial properties of these membranes using BSA and Escherichia coli as the test model, respectively. During a 150-min test, the modified membranes show much lower flux decline (42.7% for PES-g-1H0I, 22.2% for PES-g-1H1I and 7.7% for PES-g-1H5I) when compared with the pristine membrane (flux declined by 77%). The modified membranes exhibit excellent antibacterial activity (nearly 100%) when UV irradiation time was 6 min. The morphological study suggested that the E. coli on the pristine membrane showed a regular and smooth surface while that on the modified membrane was disrupted, which validated the antibacterial activity of the modified membranes.

  2. Enhanced biofouling resistance of polyethersulfone membrane surface modified with capsaicin derivative and itaconic acid

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jian [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100 (China); College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100 (China); Gao, Xueli, E-mail: gxl_ouc@126.com [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100 (China); College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100 (China); Wang, Qun; Sun, Haijing; Wang, Xiaojuan [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100 (China); College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100 (China); Gao, Congjie, E-mail: gaocjie@ouc.edu.cn [Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100 (China); College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100 (China)

    2015-11-30

    Graphical abstract: - Highlights: • PES membrane was modified with a capsaicin derivative. • UV-assisted graft polymerization was carried out on membrane surface. • The capsaicin derivative modified membrane shows better antibiofouling property. - Abstract: The culprit of biofouling is the reproduction of viable microorganisms on the membrane surface. Recently, functionalization of membrane surface with natural antibacterial agents has drawn great attention. This work presents the fabrication of antibiofouling polyethersulfone (PES) ultrafiltration (UF) membranes by UV-assisted photo grafting of capsaicin derivative (N-(4-hydroxy-3-methoxy-benzyl)-acrylamide, HMBA) and itaconic acid (IA) on the surface of PES membrane. Results of FTIR-ATR, water static contact angle (WSCA) and atomic force microscopy (AFM) analysis confirmed the successful grafting of HMBA and IA on the membrane surface. We investigated the antifouling and antibacterial properties of these membranes using BSA and Escherichia coli as the test model, respectively. During a 150-min test, the modified membranes show much lower flux decline (42.7% for PES-g-1H0I, 22.2% for PES-g-1H1I and 7.7% for PES-g-1H5I) when compared with the pristine membrane (flux declined by 77%). The modified membranes exhibit excellent antibacterial activity (nearly 100%) when UV irradiation time was 6 min. The morphological study suggested that the E. coli on the pristine membrane showed a regular and smooth surface while that on the modified membrane was disrupted, which validated the antibacterial activity of the modified membranes.

  3. Applying polarity rapid assessment method and ultrafiltration to characterize NDMA precursors in wastewater effluents.

    Science.gov (United States)

    Chen, Chao; Leavey, Shannon; Krasner, Stuart W; Mel Suffet, I H

    2014-06-15

    Certain nitrosamines in water are disinfection byproducts that are probable human carcinogens. Nitrosamines have diverse and complex precursors that include effluent organic matter, some anthropogenic chemicals, and natural (likely non-humic) substances. An easy and selective tool was first developed to characterize nitrosamine precursors in treated wastewaters, including different process effluents. This tool takes advantages of the polarity rapid assessment method (PRAM) and ultrafiltration (UF) (molecular weight distribution) to locate the fractions with the strongest contributions to the nitrosamine precursor pool in the effluent organic matter. Strong cation exchange (SCX) and C18 solid-phase extraction cartridges were used for their high selectivity for nitrosamine precursors. The details of PRAM operation, such as cartridge clean-up, capacity, pH influence, and quality control were included in this paper, as well as the main parameters of UF operation. Preliminary testing of the PRAM/UF method with effluents from one wastewater treatment plant gave very informative results. SCX retained 45-90% of the N-nitrosodimethylamine (NDMA) formation potential (FP)-a measure of the precursors-in secondary and tertiary wastewater effluents. These results are consistent with NDMA precursors likely having a positively charged amine group. C18 adsorbed 30-45% of the NDMAFP, which indicates that a substantial portion of these precursors were non-polar. The small molecular weight (MW) (10 kDa) fractions obtained from UF were the primary contributors to NDMAFP. The combination of PRAM and UF brings important information on the characteristics of nitrosamine precursors in water with easy operation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Valorisation of tuna processing waste biomass for recovery of functional and antioxidant peptides using enzymatic hydrolysis and membrane fractionation process.

    Science.gov (United States)

    Saidi, Sami; Ben Amar, Raja

    2016-10-01

    The enzymatic hydrolysis using Prolyve BS coupled to membrane process (Ultrafiltration (UF) and nanofiltration (NF)) is a means of biotransformation of tuna protein waste to Tuna protein hydrolysate (TPH) with higher added values. This method could be an effective solution for the production of bioactive compounds used in various biotechnological applications and minimizing the pollution problems generated by the seafood processing industries. The amino acid composition, functional and antioxidant properties of produced TPH were evaluated. The results show that the glutamic acid, aspartic acid, glycine, alaline, valine and leucine were the major amino acids detected in the TPH profile. After membrane fractionation process, those major amino acids were concentrated in the NF retentate (NFR). The NFR and NF permeate (NFP) have a higher protein solubility (>95 %) when compared to TPH (80 %). Higher oil and water binding capacity were observed in TPH and higher emulsifying and foam stability was found in UF retentate. The NFP showed the highest DPPH radical scavenging activity (65 %). The NFR contained antioxidant amino acid (30.3 %) showed the highest superoxide radical and reducing power activities. The TPH showed the highest iron chelating activity (75 %) compared to other peptide fractions. The effect of the membrane fractionation on the molecular weight distribution of the peptide and their bioactivities was underlined. We concluded that the TPH is a valuable source of bioactive peptides and their peptide fractions may serve as useful ingredients for application in food industry and formulation of nutritional products.

  5. Forward osmosis - a novel membrane process for concentration of low level radioactive wastes

    International Nuclear Information System (INIS)

    Ghosh, A.K.; Bindal, R.C.; Tewari, P.K.

    2013-01-01

    Forward osmosis (FO) is an emerging membrane process in which osmotic pressure differential across a semi-permeable membrane between the solution to be concentrated (feed) and a concentrated solution of high osmotic pressure (draw solution) than the feed is used to effect separation of water from dissolved solutes. With time, feed stream gets concentrated with dilution of draw solution and this technology recently being used as more energy efficient alternative to reverse osmosis (RO) in some of the application areas, particularly for the concentration of low volume high value products. The use of pressure driven membrane processes like reverse osmosis (RO) and ultrafiltration (UF) are already demonstrated in the treatment of radioactive laundry, laboratory effluents and some other applications in nuclear industry. The application of FO membrane process to concentrate simulated inactive ammonium-diuranate (ADU) filtered effluent solution (by mixing uranyl nitrate and ammonium nitrate) using indigenously developed cellulose acetate (CA) and thin-film composite polyamide (TFCP) membranes has been published recently from our laboratory. In this presentation, we briefly discuss our views on possibility of using FO membrane process with proper selection of membrane for concentration of low level radioactive wastes generated in various steps of nuclear fuel cycle in most effective way. (author)

  6. Uranium isotope exchange between gaseous UF6 and solid UF5

    International Nuclear Information System (INIS)

    Yato, Yumio; Kishimoto, Yoichiro; Sasao, Nobuyuki; Suto, Osamu; Funasaka, Hideyuki

    1996-01-01

    Based on a collision model, a new rate equation is derived for uranium isotope exchange between gaseous UF 6 and solid UF 5 by considering the number of UF 5 molecules on the solid surface to be dependent on time. The reaction parameters included in the equation are determined from the experimental data and compared with the previous ones. A remarkable agreement is found between the particle sizes of UF 5 estimated from the reaction parameter and from the direct observation with an electron microscope. The rate equation given in this work fully satisfies the related mass conservation and furthermore includes explicitly the terms related to the UF 6 density and the mean size of UF 5 particles, both of which are considered to cause an important effect on the reaction. This remarkable feature facilitates the simulation studies on this reaction under various conditions. The long term behavior of a simulated exchange reaction is studied under the condition considered to be close to that in a recovery zone of the MLIS process. The result indicates that the reaction is virtually limited to the solid surface under this conditions and thus the depletion of 235 UF 5 concentration averaged over the whole UF 5 particles is not significant even after 200 h of the exchange reaction

  7. Chemical exchange between UF6 and UF6- ion in anhydrous hydrofluoric acid

    International Nuclear Information System (INIS)

    Chatelet, J.; Luce, M.; Plurien, P.; Rigny, P.

    1975-01-01

    The chemical exchange between UF 6 and the UF 6 - ion is of potential interest for the separation of U isotopes. In this paper, results concerning the value of the separation factor and the kinetics of the homogeneous exchange are given [fr

  8. Studies on (2UF4 + H2 = 2UF3 + 2HF) and vapour pressure of UF3

    International Nuclear Information System (INIS)

    Roy, K.N.; Prasad, R.; Venugopal, V.; Singh, Z.; Sood, D.D.

    1982-01-01

    Equilibrium constants for 2UF 4 (s) + H 2 (g) = 2UF 3 (s) + 2HF(g) have been measured in the temperature range 967 to 1120 K. An expression is given for the results. The results have been treated by second- and third-law methods to obtain ΔH 0 (298.15 K) and the values are given. The value of ΔS 0 (298.15 K) has been calculated by the second-law method. An expression is given for the vapour pressure of UF 3 (s), measured by the transpiration technique in the range 1229 to 1367 K. The standard enthalpy of vaporization ΔH 0 sub(v) (298.15 K) and the standard entropy of vaporization ΔS 0 sub(v) (298.15 K) have been calculated. The vaporization results have also been used for the calculation of ΔH 0 sub(f)(UF 3 , g, 298.15 K) and ΔS 0 sub(f)(UF 3 ,g, 298.15 K). (author)

  9. An analysis of ultrafiltration applications for the oilsands

    Energy Technology Data Exchange (ETDEWEB)

    Pease, S. [Zenon Environmental Inc., Oakville, ON (Canada)

    2006-07-01

    This presentation examined ultrafiltration technologies in oil sands applications. The Athabasca region has limited water supplies, and regulatory standards regarding waterborne pathogens and disinfectant by-products are increasing. Membrane technologies are now rapidly replacing conventional water filtration technologies as they provide a more reliable means of filtration and use minimal amounts of chemicals. Membrane technologies are capable of removing 99.9 per cent of all Giardia, Cryptosporidium and viral agents from water samples, as well as various metals. ZeeWeed membrane filtration systems use a backpulse system to filter water in combination with a permeation system. Enhanced coagulation systems are used to remove colour, taste, and odours, as well as manganese and iron. The systems have been tested with Athabasca River samples, and are currently being used at several oil sands processing plants. It was concluded that ZeeWeed membrane systems are able to treat difficult waters with high pathogen and metals contents. tabs., figs.

  10. High Performance Regenerated Cellulose Membranes from Trimethylsilyl Cellulose

    KAUST Repository

    Ali, Ola

    2013-01-01

    Regenerated cellulose (RC) membranes are extensively used in medical and pharmaceutical separation processes due to their biocompatibility, low fouling tendency and solvent resistant properties. They typically possess ultrafiltration

  11. Ozonation and/or Coagulation - Ceramic Membrane Hybrid for Filtration of Impaired-Quality Source Waters

    KAUST Repository

    Ha, Changwon

    2013-09-01

    When microfiltration (MF) and ultrafiltration (UF) membranes are applied for drinking water treatment/wastewater reuse, membrane fouling is an evitable problem, causing the loss of productivity over time. Polymeric membranes have been often reported to experience rapid and/or problematical fouling, restraining sustainable operation. Ceramic membranes can be effectively employed to treat impaired-quality source waters due to their inherent robustness in terms of physical and chemical stability. This research aimed to identify the effects of coagulation and/or ozonation on ceramic membrane filtration for seawater and wastewater (WW) effluent. Two different types of MF and UF ceramic membranes obtained by sintering (i.e., TAMI made of TiO2+ZrO2) and anodic oxidation process (i.e., AAO made of Al2O3) were employed for bench-scale tests. Precoagulation was shown to play an important role in both enhancing membrane filterability and natural organic matter (NOM) removal efficacy for treating a highorganic surface water. The most critical factors were found to be pH and coagulant dosage with the highest efficiency resulting under low pH and high coagulant dose. Due to the ozone-resistance nature of the ceramic membranes, preozonation allowed the ceramic membranes to be operated at higher flux, especially leading to significant flux improvement when treating seawater in the presence of calcium and magnesium. 4 Dissolved ozone in contact with the TAMI ceramic membrane surface accelerated the formation of hydroxyl (˙OH) radicals in WW effluent treatment. Flux restoration of both ceramic membranes, fouled with seawater and WW effluent, was efficiently achieved by high backwash (BW) pressure and ozone in chemically enhanced backwashing (CEB). Ceramic membranes exhibited a pH-dependent permeate flux while filtering WW effluent, showing reduced fouling with increased pH. On the other hand, for filtering seawater, differences in permeate flux between the two membranes was

  12. Membrane processes for the reuse of car washing wastewater

    Directory of Open Access Journals (Sweden)

    Deniz Uçar

    2018-04-01

    Full Text Available This study investigates alternative treatments of car wash effluents. The car wash wastewater was treated by settling, filtration, and membrane filtration processes. During settling, total solid concentration decreased rapidly within the first 2 hours and then remained constant. Chemical oxygen demand (COD and conductivity were decreased by 10% and 4%, respectively. After settling, wastewater was filtered throughout a 100 μm filter. It was found that filtration had a negligible effect on COD removal. Finally, wastewater was filtered by four ultrafiltration membranes of varying molecular weight cutoff (MWCO (1, 5, 10 and 50 kDa and one nanofiltration membrane (NF270, MWCO = 200–400 Da. The permeate COD concentrations varied between 64.5 ± 3.2 and 85.5 ± 4.3 mg L−1 depending on UF pore size. When the NF270 nanofiltration membrane was used, the permeate COD concentration was 8.1 ± 0.4 mg L−1 corresponding to 97% removal. FeCl3 precipitation and activated carbon adsorption techniques were also applied to the retentate and 60–76% COD removals were obtained for activated carbon adsorption and FeCl3 precipitation, respectively.

  13. THE MUNICIPAL SEWAGE TREATMENT PLANT EFFLUENT POLISHING IN ULTRAFILTRATION

    Directory of Open Access Journals (Sweden)

    Mariusz Dudziak

    2017-08-01

    Full Text Available The effluent from the municipal sewage treatment plant was comparatively treated in the ultrafiltration process using ceramic and polymer membranes. Filtration was carried out in the cross-flow system under the conditions of the transmembrane process pressure 0.1 MPa - the ceramic membrane and 0.2 MPa – the polymer membrane at a temperature of 20°C. The effectiveness of the process had been assessed by various physical and chemical analyses (pH, turbidity, color, absorbance, TOC and phenol index. There was included the toxicological assessment (by applying as an indicator organism the bioluminescence bacteria Aliivibrio fischeri and microbiological assessment of tested samples. During filtration there was studied the hydraulic efficiency of membranes. Is was specified, that the efficiency of the process depends on the conditions of membrane filtration, wherein the better effects of the removal of organic pollutants had been noted in the case of polymer membrane than ceramic membrane. However, the polymer membrane, in the comparison to the ceramic membrane, was more susceptible to pore blocking, which caused the reduction of hydraulic efficiency. Regardless of what type of membrane the permeats were not toxic and did not contain microorganisms.

  14. Analysis of ultrafiltration failure in peritoneal dialysis patients by means of standard peritoneal permeability analysis.

    Science.gov (United States)

    Ho-dac-Pannekeet, M M; Atasever, B; Struijk, D G; Krediet, R T

    1997-01-01

    Ultrafiltration failure (UFF) is a complication of peritoneal dialysis (PD) treatment that occurs especially in long-term patients. Etiological factors include a large effective peritoneal surface area [measured as high mass transfer area coefficient (MTAC) of creatinine], a high effective lymphatic absorption rate (ELAR), a large residual volume, or combinations. The prevalence and etiology of UFF were studied and the contribution of transcellular water transport (TCWT) was analyzed. A new definition of UFF and guidelines for the analysis of its etiology were derived from the results. Peritoneal dialysis unit in the Academic Medical Center in Amsterdam. Cross-sectional study of standard peritoneal permeability analyses (4-hr dwells, dextran 70 as volume marker) with 1.36% glucose in 68 PD patients. Patients with negative net UF (change in intraperitoneal volume, dIPV rate (TCUFR) were lower (p lower residual volume (p = 0.03), and lower TCUFR (p = 0.01). Ultrafiltration failure was associated with a high MTAC creatinine in 3 patients, a high ELAR in 4 patients, and a combination of factors in one. As an additional possible cause, TCWT was studied, using the sodium gradient in the first hour of the dwell, corrected for diffusion (dNA). Five patients had dNA > 5 mmol/L, indicating normal TCWT. The 3 patients with dNA lower TCUFR (p = 0.04). A smaller difference was found between dIPV 3.86% and 1.36% (p = 0.04) compared to the dNA > 5 mmol/L group, but no differences were present for MTAC creatinine, ELAR, residual volume, or glucose absorption. In addition to known factors, impairment of TCWT can be a cause of UFF. A standardized dwell with 1.36% glucose overestimates UFF. Therefore, 3.86% glucose should be used for identification of patients with UFF, especially because it provides additional information on TCWT. Ultrafiltration failure can be defined as net UF exchange.

  15. Studies on improved integrated membrane-based chromatographic process for bioseparation

    Science.gov (United States)

    Xu, Yanke

    To improve protein separation and purification directly from a fermentation broth, a novel membrane filtration-cum-chromatography device configuration having a relatively impermeable coated zone near the hollow fiber module outlet has been developed. The integrated membrane filtration-cum-chromatography unit packed with chromatographic beads on the shell side of the hollow fiber unit enjoys the advantages of both membrane filtration and chromatography; it allows one to load the chromatographic media directly from the fermentation broth or lysate and separate the adsorbed proteins through the subsequent elution step in a cyclic process. Interfacial polymerization was carried out to coat the bottom section of the hollow fiber membrane while leaving the rest of the hollow fiber membrane unaffected. Myoglobin (Mb), bovine serum albumin (BSA) and a-lactalbumin (a-LA) were used as model proteins in binary mixtures. Separation behaviors of binary protein mixtures were studied in devices using either an ultrafiltration (UF) membrane or a microfiltration (MF) membrane. Experimental results show that the breakthrough time and the protein loading capacities were dramatically improved after coating in both UF and MF modules. For a synthetic yeast fermentation broth feed, the Mb and a-LA elution profiles for the four consecutive cyclic runs were almost superimposable. Due to the lower transmembrane flux in this device plus the periodical washing-elution during the chromatographic separation, fouling was not a problem as it is in conventional microfiltration. A mathematical model describing the hydrodynamic and protein loading behaviors of the integrated device using UF membrane with a coated zone was developed. The simulation results for the breakthrough agree well with the experimental breakthrough curves. The optimal length of the coated zone was obtained from the simulation. A theoretical analysis of the protein mass transfer was performed using a diffusion-convection model

  16. Cake properties in ultrafiltration of TiO2 fine particles combined with HA: in situ measurement of cake thickness by fluid dynamic gauging and CFD calculation of imposed shear stress for cake controlling.

    Science.gov (United States)

    Du, Xing; Qu, Fangshu; Liang, Heng; Li, Kai; Chang, Haiqing; Li, Guibai

    2016-05-01

    In this study, the cake buildup of TiO2 fine particles in the presence of humid acid (HA) and cake layer controlling during ultrafiltration (UF) were investigated. Specifically, we measured the cake thickness using fluid dynamic gauging (FDG) method under various solution conditions, including TiO2 concentration (0.1-0.5 g/L), HA concentration (0-5 mg/L, total organic carbon (TOC)), and pH values (e.g., 4, 6 and 10), and calculated the shear stress distribution induced by stirring using computational fluid dynamics (CFD) to analyze the cake layer controlling conditions, including the operation flux (50-200 L m(-2) h(-1)) and TiO2 concentration (0.1-0.5 g/L). It was found that lower TiO2/HA concentration ratio could lead to exceedingly severe membrane fouling because of the formation of a relatively denser cake layer by filling the voids of cake layer with HA, and pH was essential for cake layer formation owing to the net repulsion between particles. Additionally, it was observed that shear stress was rewarding for mitigating cake growth under lower operation flux as a result of sufficient back-transport forces, and exhibited an excellent performance on cake layer controlling in lower TiO2 concentrations due to slight interaction forces on the vicinity of membrane.

  17. Depleted UF6 programmatic environmental impact statement

    International Nuclear Information System (INIS)

    1997-01-01

    The US Department of Energy has developed a program for long-term management and use of depleted uranium hexafluoride, a product of the uranium enrichment process. As part of this effort, DOE is preparing a Programmatic Environmental Impact Statement (PEIS) for the depleted UF 6 management program. This report duplicates the information available at the web site (http://www.ead.anl.gov/web/newduf6) set up as a repository for the PEIS. Options for the web site include: reviewing recent additions or changes to the web site; learning more about depleted UF 6 and the PEIS; browsing the PEIS and related documents, or submitting official comments on the PEIS; downloading all or part of the PEIS documents; and adding or deleting one's name from the depleted UF 6 mailing list

  18. Corrosion of breached UF6 storage cylinders

    International Nuclear Information System (INIS)

    Barber, E.J.; Taylor, M.S.; DeVan, J.H.

    1993-01-01

    This paper describes the corrosion processes that occurred following the mechanical failure of two steel 14-ton storage cylinders containing depleted UF 6 . The failures both were traced to small mechanical tears that occurred during stacking of the cylinders. Although subsequent corrosion processes greatly extended the openings in the wall. the reaction products formed were quite protective and prevented any significant environmental insult or loss of uranium. The relative sizes of the two holes correlated with the relative exposure times that had elapsed from the time of stacking. From the sizes and geometries of the two holes, together with analyses of the reaction products, it was possible to determine the chemical reactions that controlled the corrosion process and to develop a scenario for predicting the rate of hydrolysis of UF 6 , the loss rate of HF, and chemical attack of a breached UF 6 storage cylinder

  19. Metamorphosis: Phases of UF{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Dyer, R.H. [Department of Energy, Oak Ridge, TN (United States)

    1991-12-31

    A 15-minute videotape is presented. The subject matter is 150 grams of UF{sub 6} sealed in a glass tube. Close-up views show the UF{sub 6} as phase changes are effected by the addition or removal of heat from the closed system. The solid-to-liquid transition is shown as heat is added, both slowly and rapidly. The solid phases which result from freezing and from desublimation are contrasted. In the solid state, uranium hexafluoride is a nearly-white, dense crystalline solid. The appearance of this solid depends on whether it is formed by freezing from the liquid or by desublimation from the vapor phase. If frozen from the liquid, the solid particles take the form of irregularly shaped coarse grains, while the solid product of desublimation tends to be a rather formless mass without individually distinguishable particles. The changes in state are presented in terms of the UF{sub 6} phase diagram.

  20. Anaerobic membrane bioreactor under extreme conditions (poster)

    NARCIS (Netherlands)

    Munoz Sierra, J.D.; De Kreuk, M.K.; Spanjers, H.; Van Lier, J.B.

    2013-01-01

    Membrane bioreactors ensure biomass retention by the application of micro or ultrafiltration processes. This allows operation at high sludge concentrations. Previous studies have shown that anaerobic membrane bioreactors is an efficient way to retain specialist microorganisms for treating

  1. Modification of PSf/SPSf Blended Porous Support for Improving the Reverse Osmosis Performance of Aromatic Polyamide Thin Film Composite Membranes

    Directory of Open Access Journals (Sweden)

    Li-Fen Liu

    2018-06-01

    Full Text Available In this study, modification of polysulfone (PSf/sulfonated polysulfone (SPSf blended porous ultrafiltration (UF support membranes was proposed to improve the reverse osmosis (RO performance of aromatic polyamide thin film composite (TFC membranes. The synergistic effects of solvent, polymer concentration, and SPSf doping content in the casting solution were investigated systematically on the properties of both porous supports and RO membranes. SEM and AFM were combined to characterize the physical properties of the membranes, including surface pore natures (porosity, mean pore radius, surface morphology, and section structure. A contact angle meter was used to analyze the membrane surface hydrophilicity. Permeate experiments were carried out to evaluate the separation performances of the membranes. The results showed that the PSf/SPSf blended porous support modified with 6 wt % SPSf in the presence of DMF and 14 wt % PSf had higher porosity, bigger pore diameter, and a rougher and more hydrophilic surface, which was more beneficial for fabrication of a polyamide TFC membrane with favorable reverse osmosis performance. This modified PSf/SPSf support endowed the RO membrane with a more hydrophilic surface, higher water flux (about 1.2 times, as well as a slight increase in salt rejection than the nascent PSf support. In a word, this work provides a new facile method to improve the separation performance of polyamide TFC RO membranes via the modification of conventional PSf porous support with SPSf.

  2. Renewable energy powered membrane technology. 2. The effect of energy fluctuations on performance of a photovoltaic hybrid membrane system.

    Science.gov (United States)

    Richards, B S; Capão, D P S; Schäfer, A I

    2008-06-15

    This paper reports on the performance fluctuations during the operation of a batteryless hybrid ultrafiltration--nanofiltration/reverse osmosis (UF-NF/RO) membrane desalination system powered by photovoltaics treating brackish groundwater in outback Australia. The renewable energy powered membrane (RE-membrane) system is designed to supply clean drinking water to a remote community of about 50 inhabitants. The performance of the RE-membrane system over four different solar days is summarized using four different NF membranes (BW30, NF90, ESPA4, TFC-S), and examined in more detail for the BW30 membrane. On an Australian spring day, the system produced 1.1 m3 of permeate with an average conductivity of 0.28 mS x cm(-1), recovering 28% of the brackish (8.29 mS x cm(-1) conductivity) feedwater with an average specific energy consumption of 2.3 kWh x m(-3). The RE-membrane system tolerated large fluctuations in solar irradiance (500--1200 W x m(-2)), resulting in only small increases in the permeate conductivity. When equipped with the NF90 (cloudy day) and ESPA4 (rainy day) membranes, the system was still able to produce 1.36 m(-3) and 0.85 m(-3) of good quality permeate, respectively. The TFC-S membrane was not able to produce adequate water quality from the bore water tested. It is concluded that batteryless operation is a simple and robust way to operate such systems under conditions ranging from clear skies to medium cloud cover.

  3. Flux limitation in ultrafiltration: Osmotic pressure model and gel layer model

    NARCIS (Netherlands)

    Wijmans, J.G.; Nakao, S.; Smolders, C.A.

    1984-01-01

    The characteristic permeate flux behaviour in ultrafiltration, i.e., the existence of a limiting flux which is independent of applied pressure and membrane resistance and a linear plot of the limiting flux versus the logarithm of the feed concentration, is explained by the osmotic pressure model. In

  4. Optimisation of ultrafiltration of a highly viscous protein solution using spiral-wound modules

    DEFF Research Database (Denmark)

    Lipnizki, Jens; Casani, S.; Jonsson, Gunnar Eigil

    2005-01-01

    The ultrafiltration process of highly viscous protein process water with spiral-wound modules was optimised by analysing the fouling and developing a strategy to reduce it. It was shown that the flux reduction during filtration is mainly caused by the adsorption of proteins on the membrane and no...

  5. Mixed-matrix membranes with enhanced antifouling activity: probing the surface-tailoring potential of Tiron and chromotropic acid for nano-TiO2

    Science.gov (United States)

    Pal, Avishek; Dey, T. K.; Debnath, A. K.; Bhushan, Bharat; Sahu, A. K.; Bindal, R. C.; Kar, Soumitra

    2017-09-01

    Mixed-matrix membranes (MMMs) were developed by impregnating organofunctionalized nanoadditives within fouling-susceptible polysulfone matrix following the non-solvent induced phase separation (NIPS) method. The facile functionalization of nanoparticles of anatase TiO2 (nano-TiO2) by using two different organoligands, viz. Tiron and chromotropic acid, was carried out to obtain organofunctionalized nanoadditives, FT-nano-TiO2 and FC-nano-TiO2, respectively. The structural features of nanoadditives were evaluated by X-ray diffraction, X-ray photoelectron spectroscopy, Raman and Fourier transform infrared spectroscopy, which established that Tiron leads to the blending of chelating and bridging bidentate geometries for FT-nano-TiO2, whereas chromotropic acid produces bridging bidentate as well as monodentate geometries for FC-nano-TiO2. The surface chemistry of the studied membranes, polysulfone (Psf): FT-nano-TiO2 UF and Psf: FC-nano-TiO2 UF, was profoundly influenced by the benign distributions of the nanoadditives enriched with distinctly charged sites (-SO3 -H+ ), as evidenced by superior morphology, improved topography, enhanced surface hydrophilicity and altered electrokinetic features. The membranes exhibited enhanced solvent throughputs, viz. 3500-4000 and 3400-4300 LMD at 1 bar of transmembrane pressure, without significant compromise in their rejection attributes. The flux recovery ratios and fouling resistive behaviours of MMMs towards bovine serum albumin indicated that the nanoadditives could impart stable and appreciable antifouling activity, potentially aiding in a sustainable ultrafiltration performance.

  6. Identification of effluent organic matter fractions responsible for low-pressure membrane fouling

    KAUST Repository

    Filloux, Emmanuelle

    2012-11-01

    Anion exchange resin (AER), powder activated carbon (PAC) adsorption and ozonation treatments were applied on biologically treated wastewater effluent with the objective to modify the effluent organic matter (EfOM) matrix. Both AER and PAC led to significant total organic carbon (TOC) removal, while the TOC remained nearly constant after ozonation. Liquid Chromatography-Organic Carbon Detection (LC-OCD) analysis showed that the AER treatment preferentially removed high and intermediate molecular weight (MW) humic-like structures while PAC removed low MW compounds. Only a small reduction of the high MW colloids (i.e. biopolymers) was observed for AER and PAC treatments. Ozonation induced a large reduction of the biopolymers and an important increase of the low MW humic substances (i.e. building blocks).Single-cycle microfiltration (MF) and ultrafiltration (UF) tests were conducted using commercially available hollow fibres at a constant flux. After reconcentration to their original organic carbon content, the EfOM matrix modified by AER and PAC treatments exhibited higher UF membrane fouling compared to untreated effluent; result that correlated with the higher concentration of biopolymers. On the contrary, ozonation which induced a significant degradation of the biopolymers led to a minor flux reduction for both UF and MF filtration tests. Based on a single filtration, results indicate that biopolymers play a major role in low pressure membrane fouling and that intermediate and low MW compounds have minor impact. Thus, this approach has shown to be a valid methodology to identify the foulant fractions of EfOM. © 2012 Elsevier Ltd.

  7. Surface patterning of polymeric separation membranes and its influence on the filtration performance

    Science.gov (United States)

    Maruf, Sajjad

    Polymeric membrane based separation technologies are crucial for addressing the global issues such as water purification. However, continuous operations of these processes are often hindered by fouling which increases mass transport resistance of the membrane to permeation and thus the energy cost, and eventually replacement of the membrane in the system. In comparison to other anti-fouling strategies, the use of controlled surface topography to mitigate fouling has not been realized mainly due to the lack of methods to create targeted topography on the porous membrane surface. This thesis aims to develop a new methodology to create surface-patterned polymeric separation membrane to improve their anti-fouling characteristics during filtration. First, successful fabrication of sub-micron surface patterns directly on a commercial ultrafiltration (UF) membrane surface using nanoimprint lithographic (NIL) technique was demonstrated. Comprehensive filtration studies revealed that the presence of these sub-micron surface patterns mitigates not only the onset of colloidal particle deposition, but also lowers the rate of growth of cake layer after initial deposition, in comparison with un-patterned membranes. The anti-fouling effects were also observed for model protein solutions. Staged filtration experiments, with backwash cleaning, revealed that the permeate flux of the patterned membrane after protein fouling was considerably higher than that of the pristine or un-patterned membrane. In addition to the surface-patterning of UF membranes, successful fabrication of a surface-patterned thin film composite (TFC) membrane was shown for the first time. A two-step fabrication process was carried out by (1) nanoimprinting a polyethersulfone (PES) support using NIL, and (2) forming a thin dense film atop the PES support via interfacial polymerization (IP). Fouling experiments suggest that the surface patterns alter the hydrodynamics at the membrane-feed interface, which is

  8. Use of a two-step ultrafiltration procedure to concentrate viral hemorrhagic septicemia virus (VHSV) in seawater.

    Science.gov (United States)

    Kim, Soo-Jin; Kim, Jong-Oh; Kim, Wi-Sik; Oh, Myung-Joo

    2015-11-01

    Viral hemorrhagic septicemia virus (VHSV) has been reported to be stable in both fresh as well as seawater, suggesting that VHSV exists in natural aquatic environments and might have an effect on the wild and cultured fish. However, VHSV is below the detectable limits of laboratory tests in natural seawater. In this study, a two-step ultrafiltration (UF) procedure was used to concentration of VHSV in seawater, providing samples that were tested for infectivity by cell culture and the presence of VHSV by quantitative reverse transcriptase PCR (qRT-PCR) methods. Overall, VHSV was approximately concentrated 100-1000 times in 1, 5 and 10 L, seawater volumes respectively: from 2.81×10(6) to 6.53×10(7)/mL and 10(3.3) to 10(3.8)TCID50/mL prior to the UF procedure, to 3.78×10(8), 1.16 × 10(11), and 9.12 × 10(10)/mL after the procedure. This is the first report of concentrating VHSV using an UF method that was specifically designed for seawater samples. In addition, the two-step UF procedure appears to be compatible with viral cell culture and qRT-PCR methods. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Reactions UF{sub 4} - ClF, UF{sub 4} - ClF{sub 3}, UF{sub 5} - ClF, UF{sub 5} - ClF{sub 3}; Reactions UF{sub 4} - ClF, UF{sub 4} - ClF{sub 3}, UF{sub 5} - ClF, UF{sub 5} - ClF{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Luce, M; Benoit, R; Hartmanshenn, O [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-07-01

    The reaction between ClF{sub 3} and UF{sub 4} is partially explained by the study of the reactions of the three systems: UF{sub 4}-ClF, UF{sub 5}-ClF and UF{sub 5}-ClF{sub 3}. The analytical techniques used are: the micro-sublimation, the infra-red spectroscopy and the thermogravimetry. The origin of the by-products is indicated. (authors) [French] La reaction entre ClF{sub 3} et UF{sub 4} est partiellement expliquee grace a l'etude des reactions des trois systemes UF{sub 4}-ClF, UF{sub 5}-ClF et UF{sub 5}-ClF{sub 3}. Les techniques analytiques utilisees sont: la micro-sublimation, la spectroscopie infrarouge et la thermogravimetrie. L'origine des sous-produits est indiquee. (auteurs)

  10. Meta-Analysis of Ultrafiltration versus Diuretics Treatment Option for Overload Volume Reduction in Patients with Acute Decompensated Heart Failure.

    Science.gov (United States)

    Barkoudah, Ebrahim; Kodali, Sindhura; Okoroh, Juliet; Sethi, Rosh; Hulten, Edward; Suemoto, Claudia; Bittencourt, Marcio Sommer

    2015-05-01

    Although diuretics are mainly used for the treatment of acute decompensated heart failure (ADHF), inadequate responses and complications have led to the use of extracorporeal ultrafiltration (UF) as an alternative strategy for reducing volume overloads in patients with ADHF. The aim of our study is to perform meta-analysis of the results obtained from studies on extracorporeal venous ultrafiltration and compare them with those of standard diuretic treatment for overload volume reduction in acute decompensated heart failure. MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials databases were systematically searched using a pre‑specified criterion. Pooled estimates of outcomes after 48 h (weight change, serum creatinine level, and all-cause mortality) were computed using random effect models. Pooled weighted mean differences were calculated for weight loss and change in creatinine level, whereas a pooled risk ratio was used for the analysis of binary all-cause mortality outcome. A total of nine studies, involving 613 patients, met the eligibility criteria. The mean weight loss in patients who underwent UF therapy was 1.78 kg [95% Confidence Interval (CI): -2.65 to -0.91 kg; p diuretic therapy. The post-intervention creatinine level, however, was not significantly different (mean change = -0.25 mg/dL; 95% CI: -0.56 to 0.06 mg/dL; p = 0.112). The risk of all-cause mortality persisted in patients treated with UF compared with patients treated with standard diuretics (Pooled RR = 1.00; 95% CI: 0.64-1.56; p = 0.993). Compared with standard diuretic therapy, UF treatment for overload volume reduction in individuals suffering from ADHF, resulted in significant reduction of body weight within 48 h. However, no significant decrease of serum creatinine level or reduction of all-cause mortality was observed.

  11. UF{sub 6} cylinder fire test

    Energy Technology Data Exchange (ETDEWEB)

    Park, S.H. [Oak Ridge K-25 Site, Oak Ridge, TN (United States)

    1991-12-31

    With the increasing number of nuclear reactors for power generation, there is a comparable increase in the amount of UF{sub 6} being transported. Likewise, the probability of having an accident involving UF{sub 6}-filled cylinders also increases. Accident scenarios which have been difficult to assess are those involving a filled UF{sub 6} cylinder subjected to fire. A study is underway at the Oak Ridge K-25 Site, as part of the US DOE Enrichment Program, to provide empirical data and a computer model that can be used to evaluate various cylinder-in-fire scenarios. It is expected that the results will provide information leading to better handling of possible fire accidents as well as show whether changes should be made to provide different physical protection during shipment. The computer model being developed will be capable of predicting the rupture of various cylinder sizes and designs as well as the amount of UF{sub 6}, its distribution in the cylinder, and the conditions of the fire.

  12. The source of net ultrafiltration during hemodialysis is mostly the extracellular space regardless of hydration status.

    Science.gov (United States)

    Jeong, Hyeonju; Lim, Chae-Wan; Choi, Hye-Min; Oh, Dong-Jin

    2016-01-01

    Fluid shifts are common in patients undergoing chronic hemodialysis (HD) during the intradialytic periods, as several liters of fluid are removed during ultrafiltration (UF). Some patients have experienced frequent intradialytic hypotension (IDH). However, the characteristics of fluid shifts and which fluid space is affected remain controversial. Therefore, we designed this study to evaluate the fluid spaces most affected by UF and to determine whether hydration status influences the fluid shifts during HD. This was a prospective cohort study of 40 patients undergoing HD. We measured the patient's fluid spaces using a whole-body bioimpedance apparatus to evaluate the changes in the fluid spaces before HD and 1-4 hours of HD and 30 minutes after HD. UF achieved during HD by the 40 patients (age, 60.0 ± 5.2 years; 50% men; 50% of patients with diabetes; body weight, 61.3 ± 10.5 kg) was 2.18 ± 0.78 L (measured fluid overload, 2.15 ± 1.24 L). 1) Mean relative reduction of total body water and extracellular water was reduced from the start to the end of HD. 2) However, mean relative reduction of intracellular water was not reduced from the start to the end of HD. 3) No significant differences in fluid shifts were observed according to hydration status. The source of net UF during HD is mostly the extracellular space regardless of hydration status. Thus, IDH may be related to differences in the interstitial fluid shift to the vascular space. © 2015 International Society for Hemodialysis.

  13. A new method to evaluate patient characteristic response to ultrafiltration during hemodialysis.

    Science.gov (United States)

    Casagrande, G; Teatini, U; Romei Longhena, G; Miglietta, F; Fumero, R; Costantino, M L

    2007-05-01

    Several factors are involved in the pathogenesis of dialysis discomfort interfering with optimal fluid removal and reducing the efficacy of the treatment; the most important one is a decrease in blood volume caused by an imbalance between ultrafiltration (UF) and plasmarefilling (PR) rates. This study is aimed at devising a method to tailor the dialysis therapy to each individual patient, by analyzing the relationship between PR and UF during the sessions in stable patients and widening the knowledge of fluid exchanges during the treatment. Thirty stable patients undergoing maintenance hemodialysis were enrolled. Three dialysis sessions were monitored for each patient; systemic pressure, blood composition, blood volume % variation, weight loss and conductivity were recorded repeatedly. A Plasma Refilling Index (PRI), defined and calculated by means of parameters measured throughout the dialysis, was introduced as a novel instrument to study plasma refilling phenomena. Results. The PRI provides understanding of patient response (in terms of plasma refilling) to the set UF. In the monitored sessions, the PRI trend is found to be characteristic of each patient; a PRI course that is at variance with the characteristic trend is a signal of inadequate or unusual dialysis scheduling. Moreover, statistical analysis highlights two different PRI trends during the first hour and during the rest of the treatment, suggesting the presence of different treatment phases. The main advantage of the PRI index is that it is non-invasive peculiar to each patient and easy to compute in a dialysis routine based on online data recorded by the monitor. A deviation from the characteristic trend may be a warning for the clinician. The analysis of the PRI trend also suggests how to modulate UF as a function of interstitial to intravascular fluid removal balance during dialysis.

  14. On the Recent Use of Membrane Technology for Olive Mill Wastewater Purification

    Directory of Open Access Journals (Sweden)

    Javier Miguel Ochando-Pulido

    2015-09-01

    Full Text Available Many reclamation treatments as well as integrated processes for the purification of olive mill wastewaters (OMW have already been proposed and developed but not led to completely satisfactory results, principally due to complexity or cost-ineffectiveness. The olive oil industry in its current status, composed of little and dispersed factories, cannot stand such high costs. Moreover, these treatments are not able to abate the high concentration of dissolved inorganic matter present in these highly polluted effluents. In the present work, a review on the actual state of the art concerning the treatment and disposal of OMW by membranes is addressed, comprising microfiltration (MF, ultrafiltration (UF, nanofiltration (NF, and reverse osmosis (RO, as well as membrane bioreactors (MBR and non-conventional membrane processes such as vacuum distillation (VD, osmotic distillation (OD and forward osmosis (FO. Membrane processes are becoming extensively used to replace many conventional processes in the purification of water and groundwater as well as in the reclamation of wastewater streams of very diverse sources, such as those generated by agro-industrial activities. Moreover, a brief insight into inhibition and control of fouling by properly-tailored pretreatment processes upstream the membrane operation and the use of the critical and threshold flux theories is provided.

  15. Combining electrophoresis with detection under ultraviolet light and multiple ultrafiltration for isolation of humic fluorescence fractions.

    Science.gov (United States)

    Trubetskaya, Olga E; Shaloiko, Lubov A; Demin, Dmitrii V; Marchenkov, Victor V; Proskuryakov, Ivan I; Coelho, Christian; Trubetskoj, Oleg A

    2011-04-01

    Polyacrylamide gel electrophoresis of chernozem soil humic acids (HAs) followed by observation under UV (312 nm) excitation light reveals new low molecular weight (MW) fluorescent fractions. Ultrafiltration of HAs sample in 7 M urea on a membrane of low nominal MW retention (NMWR, 5 kDa) was repetitively used for separation of fluorescent and non-fluorescent species. Thirty ultrafiltrates and the final retentate R were obtained. Fluorescence maxima of separate ultrafiltrates were different and non-monotonously changed in the range of 475-505 nm. Fluorescence maxima of less than 490 nm were detected only in the four first utrafiltrates. For further physical-chemical analyses all utrafiltrates were combined into a fraction called UFchernozem soil HAs complex. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Membrane Processes Based on Complexation Reactions of Pollutants as Sustainable Wastewater Treatments

    Directory of Open Access Journals (Sweden)

    Teresa Poerio

    2009-11-01

    Full Text Available Water is today considered to be a vital and limited resource due to industrial development and population growth. Developing appropriate water treatment techniques, to ensure a sustainable management, represents a key point in the worldwide strategies. By removing both organic and inorganic species using techniques based on coupling membrane processes and appropriate complexing agents to bind pollutants are very important alternatives to classical separation processes in water treatment. Supported Liquid Membrane (SLM and Complexation Ultrafiltration (CP-UF based processes meet the sustainability criteria because they require low amounts of energy compared to pressure driven membrane processes, low amounts of complexing agents and they allow recovery of water and some pollutants (e.g., metals. A more interesting process, on the application point of view, is the Stagnant Sandwich Liquid Membrane (SSwLM, introduced as SLM implementation. It has been studied in the separation of the drug gemfibrozil (GEM and of copper(II as organic and inorganic pollutants in water. Obtained results showed in both cases the higher efficiency of SSwLM with respect to the SLM system configuration. Indeed higher stability (335.5 vs. 23.5 hours for GEM; 182.7 vs. 49.2 for copper(II and higher fluxes (0.662 vs. 0.302 mmol·h-1·m-2 for GEM; 43.3 vs. 31.0 for copper(II were obtained by using the SSwLM. Concerning the CP-UF process, its feasibility was studied in the separation of metals from waters (e.g., from soil washing, giving particular attention to process sustainability such as water and polymer recycle, free metal and water recovery. The selectivity of the CP-UF process was also validated in the separate removal of copper(II and nickel(II both contained in synthetic and real aqueous effluents. Thus, complexation reactions involved in the SSwLM and the CP-UF processes play a key role to meet the sustainability criteria.

  17. Obtaining of uranium tetrafluoride UF4 by electrodialysis reactive from uranium concentrates

    International Nuclear Information System (INIS)

    Munoz Lay, Danny Mauricio

    2014-01-01

    The generation of uranium fuels has always been a topic worldwide. The uranium fuel manufacturing base is made under very strict parameters of radiological and industrial safety, being a stage called 'nuclear fuel cycle'. In Chile, it is done constant research for fuels. This report focuses primarily on participating in such research; mainly in the production of uranium tetrafluoride (UF 4 ) .The tetrafluoride production is very crucial for the nuclear fuel industry. Its production varies from precipitation in stirred conditions to electrolysis in mercury. However, both processes has shortcomings either in performance and environmental pollution, which is why it is proposed a new method of production based on a friendly process to the environment and easier to operate, the reactive electrodialysis (RED). Electrodialysis is a hybrid reactive process of separation by membranes, cationic and / or anionic, namely, ionic species. In the process, ions are induced to move by an electric potential applied and separated by these membranes, a highly selective physical barrier which allows passage of ions with certain charge, and prevents the passage of oppositely charged ions. And in turn, it is reactive because it forces a chemical reaction, redox, to obtain uranium tetrafluoride (UF 4 ). The results of these experiments show that by reactive electrodialysis, NH 4 UF 5 deposits were obtained. However, calcinating the NH 4 UF 5 to 450 o C, it decomposes to obtain uranium tetrafluoride, UF 4 . The best working conditions were obtained with an electric current of 0.5 (A), 41 o C and a flow of 16 (ml / s) of the electrolyte. It was possible to obtain 5,995 (g) to 3 (h), giving a current efficiency of 71.42%. In turn, working at high temperatures and flow recirculation is possible to operate with a potential difference of 1.7 (V)

  18. Structural Study and Modification of Support Layer for Forward Osmosis Membranes

    KAUST Repository

    Shi, Meixia

    2016-06-01

    Water scarcity is a serious global issue, due to the increasing population and developing economy, and membrane technology is an essential way to address this problem. Forward osmosis (FO) is an emerging membrane process, due to its low energy consumption (not considering the draw solute regeneration). A bottleneck to advance this technology is the design of the support layer for FO membranes to minimize the internal concentration polarization. In this dissertation, we focus on the structural study and modification of the support layer for FO membranes. Firstly, we digitally reconstruct different membrane morphologies in 3D and propose a method for predicting performance in ultrafiltration operations. Membranes with analogous morphologies are later used as substrate for FO membranes. Secondly, we experimentally apply substrates with different potentially suitable morphologies as an FO support layer. We investigate their FO performance after generating a selective polyamide layer on the top, by interfacial polymerization. Among the different substrates we include standard asymmetric porous membranes prepared from homopolymers, such as polysulfone. Additionally block copolymer membrane and Anodisc alumina membrane are chosen based on their exceptional structures, with cylindrical pores at least in part. 3D digitally reconstructed porous substrates, analogous to those investigated for ultrafiltration, are then used to model the performance in FO operation. Finally, we analyze the effect of intermediate layers between the porous substrate and the interfacial polymerized layer. We investigate two materials including chitosan and hydrogel. The main results are the following. Pore-scale modeling for digital membrane generation effectively predicts the velocity profile in different layers of the membrane and the performance in UF experiments. Flow simulations confirm the advantage of finger-like substrates over sponge-like ones, when high water permeance is sought

  19. Styrene process condensate treatment with a combination process of UF and NF for reuse.

    Science.gov (United States)

    Wang, Aijun; Liu, Guangmin; Huang, Jin; Wang, Lijuan; Li, Guangbin; Su, Xudong; Qi, Hong

    2013-01-15

    Aiming at reusing the SPC to save water resource and heat energy, a combination treatment process of UF/NF was applied to remove inorganic irons, suspended particles and little amount of organic contaminants in this article. To achieve the indexes of CODM≤5.00 mg L(-1), oil≤2.00 mg L(-1), conductivity≤10.00 μs cm(-1), pH of 6.0-8.0, the NF membrane process was adopted. It was necessary to employ a pretreatment process to reduce NF membrane fouling. Hence UF membrane as an efficient pretreatment unit was proposed to remove the inorganic particles, such as iron oxide catalyst, to meet the influent demands of NF. The effluent of UF, which was less than 0.02 mg L(-1) of total iron, went into a security filter and then was pumped into the NF process unit. High removal efficiencies of CODM, oil and conductivity were achieved by using NF process. The ABS grafting copolymerization experiment showed that the effluent of the combination process met the criteria of ABS production process, meanwhile the process could alleviate the environment pollution. It was shown that this combination process concept was feasible and successful in treating the SPC. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Thermal plasma reduction of UF6

    International Nuclear Information System (INIS)

    Fincke, J.R.; Swank, W.D.; Haggard, D.C.

    1995-01-01

    This paper describes the experimental demonstration of a process for the direct plasma reduction of depleted uranium hexafluoride to uranium metal. The process exploits the large departures from equilibrium that can be achieved in the rapid supersonic expansion of a totally dissociated and partially ionized mixture of UF 6 , Ar, He, and H 2 . The process is based on the rapid condensation of subcooled uranium vapor and the relatively slow rate of back reaction between metallic uranium and HF to F 2 to reform stable fluorides. The high translational velocities and rapid cooling result in an overpopulation of atomic hydrogen which persists throughout the expansion process. Atomic hydrogen shifts the equilibrium composition by inhibiting the reformation of uranium-fluorine compounds. This process has the potential to reduce the cost of reducing UF 6 to uranium metal with the added benefit of being a virtually waste free process. The dry HF produced is a commodity which has industrial value

  1. New regulatory aspects of UF6 transport

    International Nuclear Information System (INIS)

    Biaggio, A.L.; Lee Gonzales, H.M.; Lopez Vietri, J.R.; Novo, R.G.

    1987-01-01

    In nuclear industry, a great amount of uranium is transformed from a chemical form to another. When the fuel cycle requires enrichment, uranium hexafluoride (UF 6) is handled, stored and transported in great quantities. To analyze the risks involved in possible accidents associated with UF 6 , radiological and chemical aspects must be considered. So far, the international practice was based on the adoption of regulations from a particular country (ANSI No. 14.1-1982.U.S.A.). In this way, the adoption of these norms at international level is difficult. For that reason, the International Atomic Energy Agency has attempted to consider the chemical risks associated with UF 6 in order to establish a more universal basis ('Recommendations for Providing Protection during the Transport of Uranium Hexafluoride' IAEA-TECDOC-423, Vienna, June 1987 - Austria). A critical analysis of these recommendations is presented in this work. The coherence and the degree of completion of the new recommendations are evaluated and the safety level is compared with that of the accepted regulations for toxic or corrosive substances and for radioactive materials transport. (Author)

  2. FLUX PROFILES AND MATHEMATICAL MODELING OF FOULING MECHANISM FOR ULTRAFILTRATION OF KONJAC GLUCOMANNAN

    Directory of Open Access Journals (Sweden)

    NITA ARYANTI

    2016-07-01

    Full Text Available This study was focused on principles and fouling analysis of konjac glucomannan (KGM separation using ultrafiltration system. Two Polyethersulfone membranes (PES having molecular weight cut-off of 10 and 20 kDa were used. It was found that membrane having larger pore size provided higher flux profiles. Evaluation of different transmembrane pressures resulted on possibility of more severe fouling at higher membrane pressure. With the increase of konjac glucomannan concentration, decrease of profile flux was observed. Further, a simple mathematical modelling of fouling mechanism was analyzed based on Hermia’s model. The images of membrane surfaces and cross-sections obtained by scanning electron microscopy (SEM were examined and being compared with the model. The research found that the fouling mechanisms of KGM ultrafiltration using membrane with pore size of 10 kDa was complete blocking. On the contrary, cake/gel layer formation was a fouling mechanism for ultrafiltration system with pore size of 20kDa.

  3. Liquid Whey Protein Concentrates Produced by Ultrafiltration as Primary Raw Materials for Thermal Dairy Gels

    Directory of Open Access Journals (Sweden)

    Marta Henriques

    2017-01-01

    Full Text Available The aim of this work is to study the gelation properties of liquid whey protein concentrates (LWPC produced by ultrafiltration (UF as raw material for thermally induced gels intended for food applications. LWPC thermal gelation was performed using different types of LWPC (non-defatted, defatted and diafiltered of different protein mass fractions and pH. Most of the produced gels showed viscoelastic behaviour. Non-defatted LWPC gave stronger heat-induced gels with a more cohesive microstructure, a higher water holding capacity and also higher elastic modulus (G’ and viscous modulus (G’’. Gel properties were not improved in products with lower content of non-protein compounds. As expected, the increase in protein mass fraction positively influences protein interactions. However, the pH is responsible for the equilibrium between attraction and repulsion forces in the gel components that influence gel hardness and water holding capacity.

  4. Purification of Drug Loaded PLGA Nanoparticles Prepared by Emulsification Solvent Evaporation Using Stirred Cell Ultrafiltration Technique.

    Science.gov (United States)

    Paswan, Suresh K; Saini, T R

    2017-12-01

    The emulsifiers in an exceedingly higher level are used in the preparation of drug loaded polymeric nanoparticles prepared by emulsification solvent evaporation method. This creates great problem to the formulator due to their serious toxicities when it is to be administered by parenteral route. The final product is therefore required to be freed from the used surfactants by the conventional purification techniques which is a cumbersome job. The solvent resistant stirred cell ultrafiltration unit (Millipore) was used in this study using polyethersulfone ultrafiltration membrane (Biomax®) having pore size of NMWL 300 KDa as the membrane filter. The purification efficiency of this technique was compared with the conventional centrifugation technique. The flow rate of ultrafiltration was optimized for removal of surfactant (polyvinyl alcohol) impurities to the acceptable levels in 1-3.5 h from the nanoparticle dispersion of tamoxifen prepared by emulsification solvent evaporation method. The present investigations demonstrate the application of solvent resistant stirred cell ultrafiltration technique for removal of toxic impurities of surfactant (PVA) from the polymeric drug nanoparticles (tamoxifen) prepared by emulsification solvent evaporation method. This technique offers added benefit of producing more concentrated nanoparticles dispersion without causing significant particle size growth which is observed in other purification techniques, e.g., centrifugation and ultracentrifugation.

  5. The process research of drying UF4 by microwave

    International Nuclear Information System (INIS)

    Wen Guo; Wang Yunbo; Liu Long

    2010-01-01

    This paper make use of microwave to dry UF 4 filter cake, the aim is desorbed adsorption water. The research focus on such process conditions, boat material, thickness of filter cake, drying time, setting temperature, heating power and so on. the research of desorption crystal water of UF 4 that dried by microwave in fixed bed .When UF 4 drying by microwave and claiming by fixed bed, the qualified UF 4 powder is prepared. The research is shown that microwave can desorbs adsorption water which contain in UF 4 filter cake. There is a stable water contents in UF 4 after drying, and the sum of two members is less. After drying by microwave and claiming by fixed bed, the contents of water, UO 2 and UO 2 F 2 are all according to the quality standard. (authors)

  6. An ultrafiltration assay for lysyl oxidase

    International Nuclear Information System (INIS)

    Shackleton, D.R.; Hulmes, D.J.

    1990-01-01

    A modification of the original microdistillation assay for lysyl oxidase is described in which Amicon C-10 microconcentrators are used to separate, by ultrafiltration, the 3H-labeled products released from a [4,5-3H]-lysine-labeled elastin substrate. Enzyme activity is determined by scintillation counting of the ultrafiltrate, after subtraction of radioactivity released in the presence of beta-aminopropionitrile, a specific inhibitor of the enzyme. Conditions are described which optimize both the sensitivity and the efficient use of substrate. The assay shows linear inhibition of activity in up to 1 M urea; hence, as the enzyme is normally diluted in the assay, samples in 6 M urea can be assayed directly, without prior dialysis, and corrected for partial inhibition. Comparable results are obtained when enzyme activity is assayed by ultrafiltration or microdistillation. The assay is simple and convenient and, by using disposable containers throughout, it eliminates the need for time-consuming decontamination of radioactive glassware

  7. Concentrating biomass of fermented broccoli (Brassica oleracea) and spinach (Amaranthus sp.) by ultrafiltration for source of organic acids and natural antioxidant

    Science.gov (United States)

    Aspiyanto, Susilowati, Agustine; Lotulung, Puspa D.; Maryati, Yati

    2017-11-01

    Organic acids and polyphenol from fermentation of green vegetables by Kombucha culture are novelty functional food to achieve prebiotic and natural antioxidant. Ultrafiltration (UF) mode was performed to concentrate biomass of fermented broccoli (Brassica oleracea L.) and spinach (Amaranthus spp.) at stirrer rotation speed of 200, 300 and 400 rpm, room temperature and trans membrane pressure 40 psia for 30 minutes. Based on total organic acids, experiment activity showed that the best treatment on biomass of fermented broccoli and spinach were reached at stirrer rotation speed of 400 rpm and 300 rpm, respectively. In this condition, fermented broccoli and spinach concentrates gave total acids 0.83 % and 0.81 %, total polyphenol 0.06 % and 0.11 %, reducing sugar 63.95 mg/mL and 20.54 mg/mL, total sugars 2.43 ug/mL and 2.28 ug/mL, total solids 6.42 % and 7.17 %, respectively. Compared with feed, the optimum condition on fermented spinach and broccoli concentrates increased total acids 13.33 % and 10 %, however decreased total polyphenol 34.1 % and 41 %. Identification on monomer from fermented spinach and broccoli at optimum condition on lactic acid were dominated by monomers with molecular weights (MWs) 252.19 and 252.36 Dalton (Da.), and monomer of polyphenol dominated by monomer with MWs 193.17 and 193.22 Da. and relative intensity 100 %. Fermented broccoli has potency as prebiotic, meanwhile fermented spinach has potency as anti oxidant.

  8. Studies on preparation of medium fat liquid dairy whitener from buffalo milk employing ultrafiltration process.

    Science.gov (United States)

    Khatkar, Sunil Kumar; Gupta, Vijay Kumar; Khatkar, Anju Boora

    2014-09-01

    A study was conducted to develop good quality medium fat liquid dairy whitener from buffalo milk employing ultrafiltration (UF) process. The buffalo skim milk was UF concentrated to 4.05 to 4.18 (23.63 ± 0.30 % TS) fold and standardized to 10 % fat (on Dry Matter Basis) (i.e. formulation) and homogenized at 175.76 kg/cm(2). The addition of 0.4 % mixture of monosodium and disodium phosphate (2:1 w/w) improved the heat stability of homogenized formulation to an optimum of 66 min. The bland flavour of homogenized formulation with added 0.4 % mixture of monosodium phosphate and disodium phosphate (2:1 w/w) and 18 % sugar (on DMB) (i.e. medium fat liquid dairy whitener) was improved significantly (P coffee was significantly (P market dairy whitener samples. At 2 % solids level, standardized medium fat liquid dairy whitener in tea/coffee fetched significantly (P market sample at 3 % solids level. There could be clear 33 % solids quantity saving in case of developed product compared to market dairy whitener sample.

  9. Assessment of UF6 Equation of State

    Energy Technology Data Exchange (ETDEWEB)

    Brady, P; Chand, K; Warren, D; Vandersall, J

    2009-02-11

    A common assumption in the mathematical analysis of flows of compressible fluids is to treat the fluid as a perfect gas. This is an approximation, as no real fluid obeys the perfect gas relationships over all temperature and pressure conditions. An assessment of the validity of treating the UF{sub 6} gas flow field within a gas centrifuge with perfect gas relationships has been conducted. The definition of a perfect gas is commonly stated in two parts: (1) the gas obeys the thermal equation of state, p = {rho}RT (thermally perfect), and, (2) the gas specific heats are constant (calorically perfect). Analysis indicates the thermally perfect assumption is valid for all flow conditions within the gas centrifuge, including shock fields. The low operating gas pressure is the primary factor in the suitability of the thermally perfect equation of state for gas centrifuge computations. UF{sub 6} is not calorically perfect, as the specific heats vary as a function of temperature. This effect is insignificant within the bulk of the centrifuge gas field, as gas temperatures vary over a narrow range. The exception is in the vicinity of shock fields, where temperature, pressure, and density gradients are large, and the variation of specific heats with temperature should be included in the technically detailed analyses. Results from a normal shock analysis incorporating variable specific heats is included herein, presented in the conventional form of shock parameters as a function of inlet Mach Number. The error introduced by assuming constant specific heats is small for a nominal UF{sub 6} shock field, such that calorically perfect shock relationships can be used for scaling and initial analyses. The more rigorous imperfect gas analysis should be used for detailed analyses.

  10. Development of ultrafiltration and inorganic adsorbents: January--March 1977

    International Nuclear Information System (INIS)

    Koenst, J.W. Jr.

    1977-01-01

    Ultrafiltration media with and without the assistance of bone char filters were evaluated to determine their effectiveness in removing radionuclides from contaminated solutions. Precipitants, resin, adsorbents, and inorganic adsorbents were studied to determine their effectiveness in decontaminating solutions. A study of the effects of radiation on ultrafiltration media was initiated. An ultrafiltration media pilot plant was ordered and is being installed

  11. 3D Membrane Imaging and Porosity Visualization

    KAUST Repository

    Sundaramoorthi, Ganesh

    2016-03-03

    Ultrafiltration asymmetric porous membranes were imaged by two microscopy methods, which allow 3D reconstruction: Focused Ion Beam and Serial Block Face Scanning Electron Microscopy. A new algorithm was proposed to evaluate porosity and average pore size in different layers orthogonal and parallel to the membrane surface. The 3D-reconstruction enabled additionally the visualization of pore interconnectivity in different parts of the membrane. The method was demonstrated for a block copolymer porous membrane and can be extended to other membranes with application in ultrafiltration, supports for forward osmosis, etc, offering a complete view of the transport paths in the membrane.

  12. Characterization of Irreversible Fouling after Ultrafiltration of Thermomechanical Pulp Mill Process Water

    DEFF Research Database (Denmark)

    Thuvander, Johan; Zarebska, Agata; Hélix-Nielsen, Claus

    2018-01-01

    process streams is fouling of the membranes. Fouling not only increases operating costs but also reduces the operating time of the membrane plant. When optimizing the membrane cleaning method, it is important to know which compounds cause the fouling. In this work fouling of an ultrafiltration membrane...... was studied. The fouling propensity of untreated process water and microfiltrated process water was compared. Fouled membranes were analyzed using scanning electron microscopy and attenuated total reflection Fourier transform infrared spectrometry. Acid hydrolysis of membranes exposed to untreated process......Large volumes of wastewater with dissolved wood components are treated in wastewater treatment plants at thermomechanical pulp mills. It has been shown previously that hemicelluloses in these wastewater streams can be recovered by membrane filtration. A serious obstacle when treating lignocellulose...

  13. The impact of chemical cleaning on separation efficiency and properties of reverse osmosis membrane

    KAUST Repository

    Baatiyyah, Hani

    2018-04-01

    One of most major concerns from both cost-effective and technical point of view in membrane process industry is membrane cleaning. The aim of the project was to investigate the variations in membrane surface properties and separation efficiency of reverse osmosis membrane. Compativtive analysis have to be performed on four RO membrane before and after exposing the virgin membrane into chemical cleaning to identify and analysis the impact of the chemical cleaning on the performance of RO membrane. Commerical chemical cleaning used in this project were caustic and acidic cleaning agent. The project’s aim is the investigation of simulation software’s precision for the four membranes performance projection at different conditions of the feed water. The assessment of the membranes performance was done in the Innovation Cluster at pilot plant that was industrial in size. The main commercial elements used were the thin-film composite membranes with a spiral-wound of 8-inch polyamide. Ultrafiltration (UF) and seawater RO membrane pretreatment process was done for the red sea sourced feed water. A pressure vessel dimensioned at 8-inch was operated in conjunction with an individual element at 8 -20 m3/hr feed flow rate, with an 8 to 12 % recovery and an average 35,000-42,000 mg/L of total dissolved solids (TDS) composition for the feed water. To achieve the project’s aim in assessing the membranes, three phase experimental stages were completed. The membranes performance was assessed in terms of their water flux, salt rejection, boron rejection, bicarbonate rejection and permeate quality. In addition, the membrane surfaces were characterized after exposing the fresh membranes with a chemical cleaning reagent. The experimental results showed an increase in both permeate flow and salt passage for all studied elements. The changes in the membranes performance were systematically explained based on the changes in the charge density and chemical structure of the membranes

  14. Estudo dos parâmetros da ultrafiltração de permeado de soro de queijo fermentado por Lactococcus lactis subsp. lactis Ultrafiltration conditions of whey permeate fermented by Lactococcus lactis subsp. lactis

    Directory of Open Access Journals (Sweden)

    Viviane BRONSTEIN

    1998-04-01

    Full Text Available Permeado de soro doce, suplementado com extrato de levedura e peptona, foi utilizado como meio de crescimento para Lactococcus lactis subsp. lactis. No final da fase exponencial de crescimento, o meio de cultura fermentado foi submetido a uma ultrafiltração com o objetivo de concentrar o microrganismo. Foram realizados 6 processamentos diferentes, nos quais variou-se as condições iniciais da ultrafiltração, tendo sido avaliados os seguintes parâmetros: porosidade da membrana, pH e número de células viáveis no permeado e no retentado, a fim de ser estudado a influência de cada parâmetro na taxa de permeação da ultrafiltração. As membranas utilizadas foram eficazes como meio de barragem para o microrganismo Lactococcus lactis subsp. lactis, ficando o retentado com uma média celular de 10(8 ufc/ml e o permeado com uma média celular de 10² ufc/ml. Membranas de diferentes porosidades tiveram taxas de fluxo semelhantes. O aumento da concentração celular provocou a diminuição do fluxo. O pH também influenciou a taxa de permeação, havendo um aumento do fluxo quando foi utilizado um pH inicial mais alto.Cheese whey permeate supplemented with yeast extract and peptone was used as a growth medium for the bacteria Lactococcus lactis subsp. lactis. At the end of the exponential growth phase, the fermented growth medium was ultrafiltered to concentrate the microorganism and to evaluate the effect of the membrane porosity, inicial UF pH and cellular concentration in permeation rate during the ultrafiltration process. The membranes used were efficient as a mean of a barrage for the Lactococcus lactis subsp. lactis. On average, the cellular concentrations were 10(8 CFU/mL and 10² CFU/mL for retentate and permeate, respectively. Membranes of different porosities had very similar flux rates. Better flow rates were obtained with inicial UF pH 6,5 and with the minors micrrorganism concentration.

  15. Cellulose multilayer Membranes manufacture with Ionic liquid

    KAUST Repository

    Livazovic, Sara; Li, Z.; Behzad, Ali Reza; Peinemann, Klaus-Viktor; Nunes, Suzana Pereira

    2015-01-01

    and ultrafiltration, with thin selective layers of naturally available cellulose has been hampered by the availability of non-aggressive solvents. We propose the manufacture of cellulose membranes based on two approaches: (i) silylation, coating from solutions

  16. 3D Membrane Imaging and Porosity Visualization

    KAUST Repository

    Sundaramoorthi, Ganesh; Hadwiger, Markus; Ben Romdhane, Mohamed; Behzad, Ali Reza; Madhavan, Poornima; Nunes, Suzana Pereira

    2016-01-01

    Ultrafiltration asymmetric porous membranes were imaged by two microscopy methods, which allow 3D reconstruction: Focused Ion Beam and Serial Block Face Scanning Electron Microscopy. A new algorithm was proposed to evaluate porosity and average pore

  17. UV dissociation of vibrationally excited UF6

    International Nuclear Information System (INIS)

    Alexandre, M.; Clerc, M.; Gagnon, R.; Gilbert, M.; Isnard, P.; Nectoux, P.; Rigny, P.; Weulersse, J.M.

    1983-01-01

    Before application of laser photodissociation of UF 6 to the separation of uranium isotopes becomes practical, isotopic selectivity should be optimized. We present here results on the cross sections involved in the irradiation of UF 6 simultaneously with infrared and ultraviolet lasers, as a function of wavelengths, fluence and temperature (at 293 K and 105 K, in an adiabatic expansion). The experiment uses a Nd 3+ YAG pumped lithium niobate optical parametric oscillator as a tunable 16 μ light source. Energies of the order of 1 mJ can be obtained with linewidths smaller than 0.1 cm - . The UV source used is based on ND 3+ YAG pumped dye laser and various frequency mixing schemes. At low temperature the frequency variation of the absorbed infrared energy per molecule depends markedly on the IR fluence phisub(IR) with a maximum value varying as phisub(IR)sup(-1/2) and a frequency extension far beyond the low level absorption spectrum. The absorbed vibrational energy leads to a change in the UV cross section comparable with the effect of a rise in temperature. Using this a model is put forward to express the isotopic selectivity 235 U/ 238 U as a function of UV wavelength and IR irradiation conditions. Experimental results agree with this model, and yield to maximum selectivity close to two [fr

  18. Water-soluble metal-binding polymers with ultrafiltration: A technology for the removal, concentration, and recovery of metal ions from aqueous streams

    International Nuclear Information System (INIS)

    Smith, B.F.; Robison, T.W.; Jarvinen, G.D.

    1997-01-01

    The use of water-soluble metal-binding polymers coupled with ultrafiltration (UF) is a technology under development to selectively concentrate and recover valuable or regulated metal-ions from dilute process or waste waters. The polymers have a sufficiently large molecular size that they can be separated and concentrated using commercially available UF technology. The polymers can then be reused by changing the solution conditions to release the metal-ions, which are recovered in a concentrated form for recycle or disposal. Pilot-scale demonstrations have been completed for a variety of waste streams containing low concentrations of metal ions including electroplating wastes (zinc and nickel) and nuclear waste streams (plutonium and americium). Many other potential commercial applications exist including remediation of contaminated solids. An overview of both the pilot-scale demonstrated applications and small scale testing of this technology are presented

  19. Water-soluble metal-binding polymers with ultrafiltration: A technology for the removal, concentration, and recovery of metal ions from aqueous streams

    Energy Technology Data Exchange (ETDEWEB)

    Smith, B.F.; Robison, T.W.; Jarvinen, G.D.

    1997-12-31

    The use of water-soluble metal-binding polymers coupled with ultrafiltration (UF) is a technology under development to selectively concentrate and recover valuable or regulated metal-ions from dilute process or waste waters. The polymers have a sufficiently large molecular size that they can be separated and concentrated using commercially available UF technology. The polymers can then be reused by changing the solution conditions to release the metal-ions, which are recovered in a concentrated form for recycle or disposal. Pilot-scale demonstrations have been completed for a variety of waste streams containing low concentrations of metal ions including electroplating wastes (zinc and nickel) and nuclear waste streams (plutonium and americium). Many other potential commercial applications exist including remediation of contaminated solids. An overview of both the pilot-scale demonstrated applications and small scale testing of this technology are presented.

  20. Spectral element simulation of ultrafiltration

    DEFF Research Database (Denmark)

    Hansen, M.; Barker, Vincent A.; Hassager, Ole

    1998-01-01

    for the unknowns at the mesh nodes. This system is solved via a technique combining the penalty method, Newton-Raphson iterations, static condensation, and a solver for banded linear systems. In addition, a smoothing technique is used to handle a singularity in the boundary condition at the membrane...

  1. Parameter Identification of an Ultrafiltration Model for Organics Removal in a Full-Scale Wastewater Reclamation Plant with Sparse and Incomplete Monitoring Data.

    Directory of Open Access Journals (Sweden)

    Fu Sun

    Full Text Available Ultrafiltration (UF has become one of the dominant treatment processes for wastewater reclamation in China. Modeling is an effective instrument to understand and optimize UF systems. To this end, a previously developed UF model for organics removal was applied to the UF process in a typical, full-scale wastewater reclamation plant (WRP in China. However, the sparse and incomplete field monitoring data from the studied WRP made the traditional model analysis approaches hardly work in this case. Therefore, two strategies, namely Strategy 1 and Strategy 2, were proposed, following a regional sensitivity analysis approach, for model parameter identification. Strategy 1 aimed to identify the model parameters and the missing model input, i.e. sampling times, simultaneously, while Strategy 2 tried to separate these two processes to reduce the dimension of the identification problem through an iteration procedure. With these two strategies, the model performed well in the Qinghe WRP with the absolute relative errors between the simulated and observed total organic carbon (TOC generally below 10%. The four model parameters were all sensitive and identifiable, and even the sampling times could be roughly identified. Given the incomplete model input, these results were encouraging and added to the trustworthiness of model when it was applied to the Qinghe WRP.

  2. Technical documentation of HGSYSTEM/UF6 model

    International Nuclear Information System (INIS)

    Hanna, S.R.; Chang, J.C.; Zhang, J.X.

    1996-01-01

    MMES has been directed to upgrade the safety analyses for the gaseous diffusion plants at Paducah KY and Piketon OH. These will require assessment of consequences of accidental releases of UF 6 to the atmosphere at these plants. The HGSYSTEM model has been chosen as the basis for evaluating UF 6 releases; it includes dispersion algorithms for dense gases and treats the chemistry and thermodynamics of HF, a major product of the reaction of UF 6 with water vapor in air. Objective of this project was to incorporate additional capability into HGSYSTEM: UF 6 chemistry and thermodynamics, plume lift-off algorithms, and wet and dry deposition. The HGSYSTEM modules are discussed. The hybrid HGSYSTEM/UF 6 model has been evaluated in three ways

  3. Method and apparatus for measuring enrichment of UF6

    Science.gov (United States)

    Hill, Thomas Roy [Santa Fe, NM; Ianakiev, Kiril Dimitrov [Los Alamos, NM

    2011-06-07

    A system and method are disclosed for determining the enrichment of .sup.235U in Uranium Hexafluoride (UF6) utilizing synthesized X-rays which are directed at a container test zone containing a sample of UF6. A detector placed behind the container test zone then detects and counts the X-rays which pass through the container and the UF6. In order to determine the portion of the attenuation due to the UF6 gas alone, this count rate may then be compared to a calibration count rate of X-rays passing through a calibration test zone which contains a vacuum, the test zone having experienced substantially similar environmental conditions as the actual test zone. Alternatively, X-rays of two differing energy levels may be alternately directed at the container, where either the container or the UF6 has a high sensitivity to the difference in the energy levels, and the other having a low sensitivity.

  4. Rapid Screening and Characterization of Acetylcholinesterase Inhibitors from Yinhuang Oral Liquid Using Ultrafiltration-liquid Chromatography-electrospray Ionization Tandem Mass Spectrometry.

    Science.gov (United States)

    Zhang, Haomin; Guo, Yinan; Meng, Lingwen; Sun, Hui; Yang, Yinping; Gao, Ying; Sun, Jiaming

    2018-01-01

    At present, approximately 17-25 million people in the world suffer from Alzheimer's disease (AD). The most efficacious and acceptable therapeutic drug clinically are the acetylcholinesterase inhibitors (AChEIs). Yinhuang oral liquid is a Chinese medicine preparation which contains AChEIs according to the literatures. However, no strategy has been presented for rapid screening and identification of AChEIs from Yinhuang oral liquid. To develop a method for rapid screening and identification of AChEIs from Yinhuang oral liquid using ultrafiltration-liquid chromatography-electrospray ionization tandem mass spectrometry (UF-LC-ESI-MS/MS). In this study, UF incubation conditions such as enzyme concentration, incubation time, and incubation temperature were optimized so as to get better screening results. The AChEIs from Yinhuang oral liquid were identified by high-performance liquid chromatography-ESI-MS and the improved Ellman method was used for the AChE inhibitory activity test in vitro . The results showed that Yinhuang oral liquid can inhibit the activity of AChE. We screened and identified seven compounds with potential AChE inhibitory activity from Yinhuang oral liquid, which provided experimental basis for the treatment and prevention of AD. The current technique was used to directly screen the active ingredients with acetylcholinesterase inhibition from complex traditional Chinese medicine, which was simple, rapid, accurate, and suitable for high-throughput screening of AChEI from complex systems. A UF-LC-ESI-MS/MS method for rapid screening and identification of AChEIs from Yinhuang oral liquid was developedSeven compounds were screened and identified with potential AChE inhibitory activity from Yinhuang oral liquidIt provided experimental basis of Yinhuang oral liquid for the treating and preventing AD. Abbreviations used: (AD): Alzheimer's disease; (UF-LC-ESI-MS/MS): ultrafiltration-liquid chromatography-electrospray ionization tandem mass spectrometry; (ACh

  5. Reclamation of the wastewater from an industrial park using hollow-fibre and spiral-wound membranes: 50 m3 d(-1) pilot testing and cost evaluation.

    Science.gov (United States)

    Chu, C P; Jiaoa, S R; Hung, J M; Lu, C J; Chung, Y J

    2009-08-01

    The feasibility of reclaiming effluent from industrial park wastewater treatment plants through a membrane process was evaluated in three phases. In phase 1 we selected nine wastewater treatment plants (WWTPs), each with a design capacity exceeding 10,000 m3 d(-1), and analyzed the corresponding effluent composition. 'Potential recycling percentage', R, ranged from 50% to 80% for the industrial park WWTPs, indicating a high feasibility for the reuse of effluent. In phase 2, a 50 m3 d(-1) pilot plant was installed in one of the selected WWTPs and underwent testing for one year. The quality of the reclaimed water was suitable for general-purpose industrial use. In the two ultrafiltration (UF) modules tested, the hydrophilic polyethersulfone hollow-fibre module was more tolerant to variable properties, and had higher recycling percentages than those of backwashable hydrophobic polyvinylidene difluoride spiral-wound module. Using the spiral-wound UF module helped reduce the cost for producing 1 m3 of reclaimed water (US$0.80) compared with a hollow-fibre module (US$0.88). In phase 3, we evaluated the negative effects of refluxing the reverse osmosis retentate, containing high total dissolved solids and non-biodegradable organics, with the biological treatment unit of the upstream WWTP. Biological compactibility tests showed that the refluxed retentate ratio should be reduced to maintain the conductivity of mixed liquor in the aeration tank at less than 110% of the original value.

  6. Fracture mechanics performance of UF6 containers

    International Nuclear Information System (INIS)

    Gonzalez, M.E.; Iorio, A.F.; Crespi, J.C.

    1993-01-01

    The main purpose of this work was to determine the fracture mechanics performance of UF 6 transport cylinders type ANSI N14.1.30B, which was made from ASTM A 516 Grade 70 steel. It was assumed an internal surface axial crack subjected to stresses due to service, proof and transport accident loads. The KUMAR-GERMAN-SHIH elastoplastic methodology gave adequate results for crack depth estimation. The results validate the leak-before-break criteria for service and proof conditions but not for accident ones. In the last case a non-destructive examination must be done in order to assure the absence of defects larger than one third of the cylinder wall thickness. (Author)

  7. Flexographic newspaper deinking : treatment of wash filtrate effluent by membrane technology

    Science.gov (United States)

    B. Chabot; G.A. Krishnagopalan; S. Abubakr

    1999-01-01

    Ultrafiltration was investigated as a means to remove flexographic ink pigments from wash filtrate effluent generated from various mixtures of flexographic and offset old newspapers from deinking operations. Membrane separation efficiency was assessed from permeate flux, fouling rate, and ease of membrane regeneration (cleaning). Ultrafiltration was capable of...

  8. Membrane Bioreactors design and operation improvements: The Spanish Experience

    International Nuclear Information System (INIS)

    Iglesias Esteban, R.; Ortega de Miguel, E.; Martinez Tarifa, M. A.; Simon Andreu, P.; Moragas Bouyart, L.; Garcia Fernandez, E.; Robuste Cartro, J.; Rodriguez-Roda layret, I.

    2012-01-01

    A Membrane Bioreactor (MBR) is a modification of a conventional activated sludge (CAS) plant where the secondary settling ins replaced by a low pressure ultrafiltration (UF) or micro filtration (MF) membranes separation process in order to obtain an effluent almost free of suspended solids and microorganisms. since the first MBR installation in 2002, the number and capacity of these systems have exponentially increased in spain, driven by the high quality of the effluent which allows direct reuse and discharge into environmentally sensitive areas, the compactness and automation of these plants and the possibility of upgrading existing wastewater treatment plants (WWTP) which no longer reach the required effluent quality levels. There were 45 operating MBR systems in 2011 and the total municipal wastewater treatment capacity by this type of plants will be about 90 hm 3 in 204 when the current projects have b