scholarly journals Effects of tannic acid on membrane fouling and membrane cleaning in forward osmosis

2017 ◽  
Vol 76 (11) ◽  
pp. 3160-3170 ◽  
Author(s):  
Wanzhu Zhang ◽  
Lin Wang ◽  
Bingzhi Dong
Keyword(s):  
Tannic Acid ◽  
Calcium Ions ◽  
Membrane Fouling ◽  
Driving Forces ◽  
Forward Osmosis ◽  
Operating Conditions ◽  
Permeate Flux ◽  
Membrane Cleaning ◽  
Draw Solution ◽  
Cleaning Methods

Abstract The fouling behavior during forward osmosis (FO) was investigated. Tannic acid was used as a model organic foulant for natural organic matter analysis since the main characteristics are similar, and calcium ions were added at different concentrations to explore the anti-pollution capability of FO membranes. The initial permeate flux and calcium ions strength were varied in different operating conditions to describe membrane fouling with membrane cleaning methods. The observed flux decline in FO changed dramatically with the type of foulant and the type of draw solution used to provide the osmotic driving force. Calcium ions aggravated membrane fouling and decreased transmembrane flux. Membrane cleaning methods included physical and physicochemical approaches, and there was no obvious difference among the typical cleaning methods (i.e., membrane flushing with different types of cleaning fluids at various crossflow velocities and backwashing with varying osmotic driving forces) with respect to flux recovery. Ultrasonic cleaning damaged the membrane structure and decreased permeate flux, and reverse diffusion of salt from the draw solution to the feed side accelerated after cleaning.

scholarly journals Membrane cleaning in membrane distillation of reverse osmosis concentrate generated in landfill leachate treatment

2021 ◽  
Author(s):  
Xiaolin Jia ◽  
Kuiling Li ◽  
Baoqiang Wang ◽  
ZhiChao Zhao ◽  
Deyin Hou ◽  
...  
Keyword(s):  
Reverse Osmosis ◽  
Landfill Leachate ◽  
Membrane Fouling ◽  
Membrane Distillation ◽  
Water Recovery ◽  
Permeate Flux ◽  
Chemical Cleaning ◽  
Leachate Treatment ◽  
Membrane Cleaning ◽  
Cleaning Methods

Abstract As a thermally induced membrane separation process, membrane distillation (MD) has drawn more and more attention for the advantages of treating hypersaline wastewaters, especially the concentrate from reverse osmosis (RO) process. One of the major obstacles in widespread MD application is the membrane fouling. We investigated the feasibility of direct contact membrane distillation (DCMD) for landfill leachate reverse osmosis concentrate (LFLRO) brine treatment and systematically assessed the efficiency of chemical cleaning for DCMD after processing LFLRO brine. The results showed that 80% water recovery rate was achieved when processing the LFLRO brine by DCMD, but the membrane fouling occurred during the DCMD process, and manifested as the decreasing of permeate flux and the increasing of permeate conductivity. Analysis revealed that the serious flux reduction was primarily caused by the fouling layer that consist of organic matters and inorganic salts. Five cleaning methods were investigated for membrane cleaning, including hydrogen chloride (HCl)-sodium hydroxide (NaOH), ethylene diamine tetraacetic acid (EDTA)-NaOH, critic acid, sodium hypochlorite (NaClO) and sodium dodecyl sulphate (SDS) cleaning. Among the chemical cleaning methods investigated, the 3 wt.% SDS cleaning showed the best efficiency at recovering the performance of fouled membranes.

scholarly journals Zwitterion-Modified Ultrafiltration Membranes for Permian Basin Produced Water Pretreatment

Water ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1710 ◽  
Author(s):  
Mirjalal Babayev ◽  
Hongbo Du ◽  
Venkata S. V. Botlaguduru ◽  
Raghava R. Kommalapati
Keyword(s):  
Membrane Fouling ◽  
Oil And Gas ◽  
Produced Water ◽  
Forward Osmosis ◽  
Dip Coating ◽  
Permeate Flux ◽  
Permian Basin ◽  
Water Pretreatment ◽  
Uf Membranes ◽  
Surface Modified

Unconventional oil and gas extraction generates large quantities of produced water (PW). Due to strict environmental regulations, it is important to recover and reuse PW. In this study, commercial polyethersulfone (PES) ultrafiltration (UF) membranes were surface-modified with zwitterionic polymer 3-(3,4-Dihydroxyphenyl)-l-alanine (l-DOPA) solution to alleviate membrane fouling during the ultrafiltration of shale oil PW of the Permian Basin. UF membranes were coated in l-DOPA solution by using a dip coating technique. Membrane characterization tests confirmed successful l-DOPA coating on UF membranes. While performing the experiments, permeate flux behaviors of the uncoated and coated membranes and antifouling resistance of the zwitterionic coating were evaluated. Among the coated UF membranes with varying coating times from one day to three days, the three-day coated UF membrane showed a good flux performance and the highest fouling resistance. The flux reduced by 38.4% for the uncoated membrane, while the reduction was 16% for the three-day coated membrane after the 5 h ultrafiltration of PW. Both improvements of the flux performance and recovery ratio are attributed to a negatively-charged surface developed on the membranes after the zwitterionic coating. The UF pretreatment also improved the flux behavior of the later forward osmosis (FO) process for PW treatment.

Characteristics of membrane fouling in submerged membrane bioreactor under sub-critical flux operation

2008 ◽  
Vol 57 (4) ◽  
pp. 601-605 ◽  
Author(s):  
Y. C. Su ◽  
C. P. Huang ◽  
H. C. Lee ◽  
Jill R. Pan
Keyword(s):  
Shear Stress ◽  
Membrane Fouling ◽  
Membrane Bioreactor ◽  
Permeate Flux ◽  
Membrane Unit ◽  
Widespread Application ◽  
Critical Flux ◽  
Membrane Cleaning ◽  
Close Link ◽  
Novel Technologies

Recently, the membrane bioreactor (MBR) process has become one of the novel technologies to enhance the performance of biological treatment of wastewater. Membrane bioreactor process uses the membrane unit to replace a sediment tank, and this can greatly enhance treatment performance. However, membrane fouling in MBR restricts its widespread application because it leads to permeate flux decline, making more frequent membrane cleaning and replacement necessary, which then increases operating and maintenance costs. This study investigated the sludge characteristics in membrane fouling under sub-critical flux operation and also assessed the effect of shear stress on membrane fouling. Membrane fouling was slow under sub-critical flux operation. However, as filamentous microbes became dominant in the reactor, membrane fouling increased dramatically due to the increased viscosity and polysaccharides. A close link was found between membrane fouling and the amount of polysaccharides in soluble EPS. The predominant resistance was the cake resistance which could be minimized by increasing the shear stress. However, the resistance of colloids and solutes was not apparently reduced by increasing shear stress. Therefore, smaller particles such as macromolecules (e.g. polysaccharides) may play an important role in membrane fouling under sub-critical flux operation.

Fouling propensity of forward osmosis: investigation of the slower flux decline phenomenon

2010 ◽  
Vol 61 (4) ◽  
pp. 927-936 ◽  
Author(s):  
Winson C. L. Lay ◽  
Tzyy Haur Chong ◽  
Chuyang Y. Tang ◽  
Anthony G. Fane ◽  
Jinsong Zhang ◽  
...  
Keyword(s):  
Membrane Fouling ◽  
Ambient Pressure ◽  
Pure Water ◽  
Forward Osmosis ◽  
Hydraulic Pressure ◽  
Contributing Factors ◽  
Draw Solution ◽  
Flux Decline ◽  
Internal Concentration ◽  
Quality Water

Forward Osmosis (FO) is a membrane process that uses the natural osmotic pressure of a concentrated draw solution to extract pure water from a feed stream. The attraction of the FO process is that it uses dense membranes, while operating at ambient pressure. This means that the FO process could potentially produce high quality water with lower energy consumption, as compared to the other desalination or reclamation processes. As FO does not entail the use of hydraulic pressure, FO has been hypothesized to have lower fouling propensity than pressure driven membrane processes. Membrane fouling has significant impact on the operational sustainability and economics of the process. This study examines the possible contributing factors to the slower flux decline observed in FO experiments based on a combined experimental and modelling approach. It was found that these factors could include low water fluxes, use of hydrophilic and smooth membranes, and the effect of internal concentration polarisation that is inherent of FO. It was also found that the transmission of draw solutes from the draw solution into the feed can have significant effect on FO performance.

scholarly journals Optimization of Operating Conditions in Forward Osmosis for Osmotic Membrane Bioreactor

2009 ◽  
Vol 3 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Jian-Jun Qin ◽  
Maung Htun Oo ◽  
Guihe Tao ◽  
E. R. Cornelissen ◽  
C. J. Ruiken ◽  
...  
Keyword(s):  
Flow Pattern ◽  
Membrane Bioreactor ◽  
Concentration Polarization ◽  
Forward Osmosis ◽  
Operating Conditions ◽  
Solute Diffusion ◽  
External Concentration ◽  
Selective Layer ◽  
Draw Solution ◽  
Osmotic Membrane Bioreactor

Objective of this study was to conduct a baseline study of osmotic membrane bioreactor (OMBR) - optimization of operating conditions in forward osmosis (FO). Experiments were conducted with an FO pilot system. Tap water was used as the feed and NaCl and MgSO4 solutions were used as draw solution. Effects of various operating conditions on flux have been investigated. In addition, pure water permeability of the FO membrane was tested. It was observed that the plant operation could be stablized within 1 h. When the membrane selective layer faced to the feed, a flux of 6.3 lm-2h-1 (LMH) was achieved at 24 atm osmotic pressure and 25 °C and effects of feed velocity and air velocity on flux were not siganificant under the testing conditions due to low external concentration polarization (ECP). However, when the selective layer faced to the draw solution, the flux was enhanced by 64% due to much reduced internal concentration polarization (ICP), the flux sharply increased with an increase in velocity of the draw solution in the laminar flow pattern range due to a countable effect of dilutive external concentration polarization (DECP) and leveled off after the flow pattern became turbulent. NaCl performed much higher efficiency than MgSO4 as an osmotic agent due to a greater solute diffusion coefficient of NaCl.

Numerical Simulation of Hollow Fiber Ultrafiltration Membrane

2009 ◽  
Author(s):  
Nina Zhou ◽  
A. G. Agwu Nnanna
Keyword(s):  
Numerical Model ◽  
Hollow Fiber ◽  
Membrane Fouling ◽  
Hollow Fiber Membrane ◽  
Membrane Surface ◽  
Operating Conditions ◽  
Permeate Flux ◽  
High Productivity ◽  
Design And Optimization ◽  
Membrane Performance

Low pressure driven ultrafiltraion (UF) processes has been applied in various industries due to its economical and easy operated benefits. Hollow fiber membrane is one of the most used membrane configuration in industry, membrane fouling is the major challenge for widely usage. Most of the investigation of UF was carried out by experiments to determine the effect of different operating conditions on permeate flux. However, experiments provide limited insight information on the membrane performance. In addition, the prediction of permeate flux under different operating conditions is necessary for experimental design and optimization. The purpose of the present study is to develop a numerical model to simulate the UF process and investigate the UF mechanism. A numerical model was developed using commercial CFD package (FLUENT). The effects of various operating conditions on permeate flux were determined by experiments and simulations, the comparison of the experimental and CFD results shows good agreements. Controlling membrane fouling will maintain a high productivity. The simulations were carried out to investigate the efficiency of removing accumulated particles on membrane surface by installing spacer filaments in membrane channels. The results suggested that the zigzag type spacer has d/h = 0.5 and l/h = 5 is more economical and efficient in reducing fouling.

scholarly journals Effect of Membrane Fouling on Fertilizer-Drawn Forward Osmosis Desalination Performance

Membranes ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 243
Author(s):  
Majeda Khraisheh ◽  
Mona Gulied ◽  
Fares AlMomani
Keyword(s):  
Membrane Fouling ◽  
Pure Water ◽  
Water Flux ◽  
Forward Osmosis ◽  
Feed Solution ◽  
Cellulose Triacetate ◽  
Synthetic Wastewater ◽  
Agricultural Field ◽  
Force Microscopy ◽  
Cleaning Methods

Fertilizer-drawn forward osmosis (FDFO) has garnered immense attention for its application in the agricultural field and its potential to reuse wastewater sustainably. Membrane fouling, however, remains to be a challenge for the process. This study aims to investigate the influence of membrane fouling on the performance of the FDFO process. Synthetic wastewater (SWW) and multi-component fertilizer (MCF) were used as feed solution (FS) and draw solution (DS) with cellulose triacetate (CTA) forward osmosis (FO) membrane orientation. The performance was evaluated through water flux (WF), percentage recovery and percentage of salt reject. The WF declined from 10.32 LMH (L/m2·h) to 3.30 LMH when ultra-pure water as FS was switched with concentration FS indicating the dependence of the performance on the type of FS used. Accelerated fouling experiments conducted to verify the fouling behavior showed a decline in the water flux from 8.6 LMH to 3.09 LMH with SWW and 13.1 LMH to 3.42 LMH when deionized water was used as FS. The effects of osmotic backwashing and in situ flushing as physical cleaning methods of the foul membrane were studied through water flux and salt recovery percentage. Both cleaning methods yielded a WF close to the baseline. Osmotic backwashing yielded better results by eliminating foulant–foulant and foulant–membrane adhesion. The cleaning methods were able to recover 75% of phosphate and 60% of nitrate salts. Scanning electron microscopy (SEM), atomic force microscopy (AFM) and Fourier transform infrared (FTIR) results validated the effectiveness of the methods for the physical cleaning of foul membranes. This study underlines the importance of the FS used in FDFO and the effectiveness of osmotic backwashing as a cleaning method of FO membranes.

scholarly journals Forward osmosis membrane fouling and cleaning for wastewater reuse

2016 ◽  
Vol 7 (2) ◽  
pp. 111-120 ◽  
Author(s):  
Youngbeom Yu ◽  
Seockheon Lee ◽  
Sung Kyu Maeng
Keyword(s):  
Activated Sludge ◽  
Flow Velocity ◽  
Membrane Fouling ◽  
Suspended Solids ◽  
Wastewater Reuse ◽  
Forward Osmosis ◽  
Cross Flow ◽  
Short Period ◽  
Cross Flow Velocity ◽  
Cleaning Methods

Membrane fouling properties and different physical cleaning methods for forward osmosis (FO) and reverse osmosis (RO) laboratory-scale filtration systems were investigated. The membrane fouling, with respect to flux reduction, was lower in FO than in RO when testing an activated sludge effluent. Cross-flow velocity, air-scouring, osmotic backwashing and effect of a spacer were compared to determine the most effective cleaning method for FO. After a long period of fouling with activated sludge, the flux was fully recovered in a short period of osmotic backwashing compared with cleaning by changing cross-flow velocity and air-scouring. In this study, the osmotic backwashing was found to be the most efficient way to clean the FO membrane. The amount of RNA recovered from FO membranes was about twice that for RO membranes; biofouling could be more significant in FO than in RO. However, the membrane fouling in FO was lower than that in RO. The spacer increased the flux in FO with activated sludge liquor suspended solids of 2,500 mg/L, and there were effects of spacer on performance of FO–MBR membrane fouling. However, further studies are required to determine how the spacer geometry influences on the performance of the FO membrane.

Preliminary study of osmotic membrane bioreactor: effects of draw solution on water flux and air scouring on fouling

2010 ◽  
Vol 62 (6) ◽  
pp. 1353-1360 ◽  
Author(s):  
Jian-Jun Qin ◽  
Kiran A. Kekre ◽  
Maung H. Oo ◽  
Guihe Tao ◽  
Chee L. Lay ◽  
...  
Keyword(s):  
Osmotic Pressure ◽  
Membrane Bioreactor ◽  
Water Flux ◽  
Forward Osmosis ◽  
Operating Conditions ◽  
Draw Solution ◽  
Membrane Flux ◽  
Osmotic Membrane Bioreactor ◽  
Flux Decline ◽  
Preliminary Study

Preliminary study on a novel osmotic membrane bioreactor (OMBR) was explored. Objective of this study was to investigate the effects of draw solution on membrane flux and air scouring at the feed side on fouling tendency in a pilot OMBR system composing the anoxic/aerobic and forward osmosis (FO) processes. Domestic sewage was the raw feed, FO membrane from HTI and NaCl/MgSO4 draw solutions were used in the experiments. Fluxes of 3 l/m2/h (LMH) and 7.2 LMH were achieved at osmotic pressure of 5 and 22.4 atm, respectively. No significant flux decline was observed at 3 LMH over 190 h and at 7.2 LMH over 150 h when air scouring was provided at the feed side of the membrane. However, without air scouring, the flux at 22.4 atm osmotic pressure declined by 30% after 195 h and then levelled off. The potential advantages of the fouling reversibility with air scouring under the operating conditions of the pilot OMBR and better water quality in OMBR over the conventional MBR were preliminarily demonstrated.

Sign in / Sign up

Export Citation Format

Share Document