Assessment of Forward Osmosis in PRO Mode during Desalination of a Local Oil Refinery Effluent

In this study, the performance of a forward osmosis system was assessed over a 30-h period during desalination of a local oil refinery effluent using NaCl as the draw solute. The study was conducted with the active layer of the membrane facing the draw solution. Assessment was done based on the water flux, salt rejection (SO42− and CO32−), membrane fouling and fouling reversal after membrane cleaning. Critical to this study was the performance of manual scrubbing of the membrane after each run and the application of chemically enhanced osmotic backwash. Scanning electron microscope (SEM) analysis of the cellulose triacetate (CTA) membrane was conducted before and after cleaning to ascertain the degree of fouling and fouling reversal after membrane cleaning. The results showed an average water flux of 3.78 ± 0.13 L/m2 h, reverse solute flux (RSF) of 1.56 ± 0.11 g/m2·h, SO42− rejection of 100%, CO32− rejection of 95.66 ± 0.32% and flux recovery of 95% after membrane cleaning. This study identifies that intermittent manual scrubbing of the membrane plays a major role in overall membrane performance. It also provides a practical basis for further research and decision making in the use of FO and CTA membranes for oil refinery effluent desalination.

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

Membranes ◽

10.3390/membranes10090243 ◽

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.

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Application of forward osmosis in reusing the brackish concentrate produced in reverse osmosis plants with secondary treated wastewater as feed solution: a case study

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2016.097 ◽

2016 ◽

Vol 6 (4) ◽

pp. 533-543 ◽

Cited By ~ 1

Author(s):

W. D. Wang ◽

M. Esparra ◽

H. Liu ◽

Y. F. Xie

Keyword(s):

Reverse Osmosis ◽

Membrane Fouling ◽

Water Flux ◽

Forward Osmosis ◽

Pump Energy ◽

Feed Solution ◽

Disinfection Byproducts ◽

Treated Wastewater ◽

Membrane Flux ◽

Flux Decline

This study evaluated the feasibility of forward osmosis (FO) in diluting and reusing the concentrate produced in a reverse osmosis (RO) plant in James City County, VA. Secondary treated wastewater (STW) was used as the feed solution. Findings indicated that pH had slight effects on the water flux of the FO membrane. As the concentration of total dissolved solids (TDS) in the concentrate was diluted from 12.5 to 1.0 g/L or the temperature in the STW decreased from 23 to 10 °C, the membrane flux decreased from 2.2 to 0.59 and 0.81 L/(m2 h), respectively. The FO membrane showed a good performance in the rejection of organic pollutants, with only a small part of the protein-like substances and disinfection byproducts permeating to the diluted concentrate. During an 89-hour continuous operation, water flux decline due to membrane fouling was not observed. Controlling the TDS in the second-stage FO effluent at 1.5 g/L, approximately 8.3% of the pump energy input could be saved. The consumption of groundwater was reduced from 22.7 × 103 to 10.6 × 103 m3/d. FO was proved to be an effective method in both diluting the discharged concentrate and reducing the energy consumption of RO.

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The influences of polydopamine immersion time on characteristics and performance of polyvinylidene fluoride ultrafiltration membrane

MATEC Web of Conferences ◽

10.1051/matecconf/201819709007 ◽

2018 ◽

Vol 197 ◽

pp. 09007

Author(s):

Syawaliah Syawaliah ◽

Nasrul Arahman ◽

Medyan Riza ◽

Sri Mulyati

Keyword(s):

Polyvinylidene Fluoride ◽

Water Flux ◽

Sem Analysis ◽

Inversion Method ◽

Asymmetric Structure ◽

Pvdf Membrane ◽

Before And After ◽

Poly Ethylene ◽

And Performance ◽

Phase Inversion Method

The Polyvinylidene Fluoride (PVDF) membrane has been prepared by phase inversion method using N,N-dimethylacetamide (DMAc) as solvent and Poly Ethylene Glycol (PEG) as additive. The fabricated membrane was modified by Polydopamine (PDA) coating in concentration of 0.5 mg/ml and immersion times of 2 hours, 6 hours, and 24 hours. The characteristics and performance of the PVDF membranes before and after the modification are studied in this paper. The result of the water flux experiment showed that the PDA-coated PVDF membranes showcased a higher flux than that of pure PVDF membrane. Scanning Electron Microscopy (SEM) analysis confirmed that the membrane had an asymmetric structure consisting of two layers. There was no significant influence on the addition of PDA to the morphology of the pore matrix because the modification was done by surface coating. Fourier Transform Infrared Spectroscopy (FTIR) analysis showed that PDA was successfully introduced on the surface of PVDF membrane with the appearance of O-H from cathecol and N-H peaks at wavenumber range of 3300-3600 cm-1. Modification with PDA increased the mechanical strength of the membrane which affirmed by the results of the tensile and elongation at break evaluation.

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

Water Science & Technology ◽

10.2166/wst.2017.392 ◽

2017 ◽

Vol 76 (11) ◽

pp. 3160-3170 ◽

Cited By ~ 3

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.

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Application of forward osmosis (FO) under ultrasonication on sludge thickening of waste activated sludge

Water Science & Technology ◽

10.2166/wst.2015.341 ◽

2015 ◽

Vol 72 (8) ◽

pp. 1301-1307 ◽

Cited By ~ 11

Author(s):

Nguyen Cong Nguyen ◽

Hau Thi Nguyen ◽

Shiao-Shing Chen ◽

Nhat Thien Nguyen ◽

Chi-Wang Li

Keyword(s):

Activated Sludge ◽

Hybrid System ◽

Membrane Fouling ◽

Water Flux ◽

Forward Osmosis ◽

Bound Water ◽

Feed Solution ◽

N Removal ◽

Sludge Thickening ◽

Sludge Concentration

Forward osmosis (FO) is an emerging process for dewatering solid–liquid stream which has the potential to be innovative and sustainable. However, the applications have still been hindered by low water flux and membrane fouling when activated sludge is used as the feed solution due to bound water from microbial cells. Hence, a novel strategy was designed to increase sludge thickening and reduce membrane fouling in the FO process under ultrasonic condition. The results from the ultrasound/FO hybrid system showed that the sludge concentration reached up to 20,400 and 28,400 mg/L from initial sludge concentrations of 3000 and 8000 mg/L with frequency of 40 kHz after 22 hours, while the system without ultrasound had to spend 26 hours to achieve the same sludge concentration. This identifies that the presence of ultrasound strongly affected sludge structure as well as sludge thickening of the FO process. Furthermore, the ultrasound/FO hybrid system could achieve NH4+-N removal efficiency of 96%, PO43−-P of 98% and dissolved organic carbon (DOC) of 99%. The overall performance demonstrates that the proposed ultrasound/FO system using seawater as a draw solution is promising for sludge thickening application.

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Effect of biosurfactant as a novel draw solution on photocatalytic treatment and desalination of produced water by different forward osmosis membranes

Water Science & Technology Water Supply ◽

10.2166/ws.2019.154 ◽

2019 ◽

Vol 20 (1) ◽

pp. 240-250 ◽

Cited By ~ 3

Author(s):

Maryam Taghizadeh ◽

Daryoush Yousefi Kebria ◽

Farhad Qaderi

Keyword(s):

Produced Water ◽

Membrane Surface ◽

Water Flux ◽

Forward Osmosis ◽

Cellulose Triacetate ◽

Salt Flux ◽

Draw Solution ◽

Benzene Toluene ◽

Reverse Salt Flux ◽

Contact Angle Analysis

Abstract Water stress and environmental concerns have driven research into the treatment of produced water. In this study, a combination of forward osmosis and photocatalyst system was used for simultaneous salt removal and treatment of produced water. Furthermore, biosurfactant as a novel draw solution and the three types of forward osmosis membranes (cellulose triacetate with and without titanium dioxide (TiO2) and graphene oxide (GO) nanoparticles) were investigated. The morphology and distribution of the TiO2 and TiO2/GO on the membrane surface were assessed by various analyses including field emission scanning electron microscopy, energy dispersive X-ray and contact angle analysis. The results demonstrated that the reverse salt flux was only 0.2 g/m2 h. Moreover, benzene, toluene, ethylbenzene, and xylene (BTEX) removal efficiency in the cellulose triacetate with TiO2 and TiO2/GO membrane under UVC radiation was 62% and 78%, respectively, while the data obtained in visible light reached 80%. The use of TiO2 and TiO2/GO membranes significantly improved the permeability, water flux, photocatalytic degradation of pollutants and desalination of produced water.

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Synthesis and Characterization of CTA/CA-Based Forward Osmosis Membranes with Hydrophilic Nano-Titanium Dioxide

Materials Science Forum ◽

10.4028/www.scientific.net/msf.867.127 ◽

2016 ◽

Vol 867 ◽

pp. 127-131 ◽

Cited By ~ 3

Author(s):

Xiu Ju Wang ◽

Xin Lian Shi ◽

Shu Fang Hou ◽

Jian Hua Yang ◽

Kai Li Zhou ◽

...

Keyword(s):

Pure Water ◽

Water Flux ◽

Forward Osmosis ◽

Bath Temperature ◽

High Water ◽

Cellulose Triacetate ◽

Sem Images ◽

Salt Rejection ◽

Pure Water Flux ◽

Nano Titanium Dioxide

In this paper, a novel nanocomposite forward osmosis membrane (nTiO2-CTA/CA) was fabricated by introducing nanotitaniumdi oxide (nTiO2) into the cellulose triacetate/cellulose acetate (CTA/CA)-based casting solution using phase inversion methods. Casting composite and preparation--nTiO2 content, blend temperature and coagulating bath temperature--were tested for their effects on pure water flux and salt rejection of membranes. Results revealed that the FO membrane prepared under optimized composition showed excellent desalination performance (high water flux = 5.38 L/m2·h and salt rejection > 97 %). Moreover, SEM images showed that addition of nTiO2 resulted in nanocomposite forward osmosis membrane with a smoother surface. The contact angle of the membranes decreased from 76o to 51° with increase nTiO2 concentration from 0% to 0.10%.

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Air bubbling for membrane fouling control in a submerged direct forward osmosis system for municipal wastewater treatment

Environmental Science Water Research & Technology ◽

10.1039/c8ew00813b ◽

2019 ◽

Vol 5 (4) ◽

pp. 684-692 ◽

Cited By ~ 3

Author(s):

Yan Sun ◽

Shanshan Gao ◽

Jiayu Tian ◽

Xiujuan Hao ◽

Zhiquan Liu ◽

...

Keyword(s):

Wastewater Treatment ◽

Membrane Fouling ◽

Municipal Wastewater ◽

Water Flux ◽

Forward Osmosis ◽

Municipal Wastewater Treatment ◽

Fouling Control

Air bubbling along the membrane improves water flux, alleviates the deposition of foulants and inhibits the formation of a fouling layer.

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Polymer Having Dicationic Structure in Dumbbell Shape for Forward Osmosis Process

Polymers ◽

10.3390/polym11030571 ◽

2019 ◽

Vol 11 (3) ◽

pp. 571 ◽

Cited By ~ 2

Author(s):

Taehyung Kim ◽

Changha Ju ◽

Chanhyuk Park ◽

Hyo Kang

Keyword(s):

Aqueous Solutions ◽

Pure Water ◽

Water Flux ◽

Forward Osmosis ◽

Feed Solution ◽

Solution Temperature ◽

Solute Flux ◽

Responsive Polymers ◽

Draw Solution ◽

Efficient Recovery

The thermal-responsive polymers, poly(alkane-1,#-diylbis(tri-n-butylphosphonium) 4-vinylbenzenesulfonate) (PSSBP#, # = 8, 6, and 4), where # is the number of carbon atoms in the central bridge structure of the dicationic phosphonium moiety, were synthesized to examine their potential application as draw solutes in forward osmosis (FO). The polymers exhibited low critical solution temperature (LCST) characteristics in aqueous solutions, which is essential for recovering a draw solute from pure water. The LCSTs of the 20 wt% aqueous solutions of PSSBP8, PSSBP6, and PSSBP4 were confirmed to be approximately 30, 38, and 26 °C, respectively, which is advantageous in terms of energy requirements for the recovering draw solute. When the concentration of the PSSBP4 draw solution was 20 wt%, water flux and reverse solute flux were approximately 1.61 LMH and 0.91 gMH, respectively, in the active layer facing the draw solution (AL-DS) system when the feed solution was distilled water. The PSSBP# thermal-responsive draw solute has considerable potential for use as a next-generation draw solute because of its excellent osmotic performance and efficient recovery. Therefore, this study provides inspiration for novel ideas regarding structural transformations of polymers and their applicability as draw solutes.

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Insights into the Influence of Membrane Permeability and Structure on Osmotically-Driven Membrane Processes

Membranes ◽

10.3390/membranes11020153 ◽

2021 ◽

Vol 11 (2) ◽

pp. 153

Author(s):

Jing Wei ◽

Qianhong She ◽

Xin Liu

Keyword(s):

High Performance ◽

Water Flux ◽

Forward Osmosis ◽

Feed Solution ◽

Cellulose Triacetate ◽

Membrane Properties ◽

Structural Parameter ◽

Separation Performance ◽

Membrane Performance ◽

Internal Concentration

The success of osmotically-driven membrane (OM) technology relies critically on high-performance membranes. Yet trade-off of membrane properties, often further complicated by the strongly non-linear dependence of OM performance on them, imposes important constraint on membrane performance. This work systematically characterized four typical commercial osmotic membranes in terms of intrinsic separation parameters, structure and surface properties. The osmotic separation performance and membrane scaling behavior of these membranes were evaluated to elucidate the interrelationship of these properties. Experimental results revealed that membranes with smaller structural parameter (S) and higher water/solute selectivity underwent lower internal concentration polarization (ICP) and exhibited higher forward osmosis (FO) efficiency (i.e., higher ratio of experimental water flux over theoretical water flux). Under the condition with low ICP, membrane water permeability (A) had dominant effect on water flux. In this case, the investigated thin film composite membrane (TFC, A = 2.56 L/(m2 h bar), S = 1.14 mm) achieved a water flux up to 82% higher than that of the asymmetric cellulose triacetate membrane (CTA-W(P), A = 1.06 L/(m2 h bar), S = 0.73 mm). In contrast, water flux became less dependent on the A value but was affected more by membrane structure under the condition with severe ICP, and the membrane exhibited lower FO efficiency. The ratio of water flux (Jv TFC/Jv CTA-W(P)) decreased to 0.55 when 0.5 M NaCl feed solution and 2 M NaCl draw solution were used. A framework was proposed to evaluate the governing factors under different conditions and to provide insights into the membrane optimization for targeted OM applications.

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