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Showing papers on "Reverse osmosis published in 2013"


Journal ArticleDOI
TL;DR: In this article, the authors investigated the energy consumption of MCDI, and the fraction of energy that can be recovered during the ion desorption step of the MCDi, as a function of influent concentration, water flow rate and water recovery.

309 citations


Journal ArticleDOI
TL;DR: It is demonstrated for the first time that up to 83% of the energy used for charging the electrodes during desalination can be recovered in the regeneration step, and MCDI is more energy efficient for treatment of brackish water than reverse osmosis.
Abstract: Membrane capacitive deionization (MCDI) is a water desalination technology based on applying a cell voltage between two oppositely placed porous carbon electrodes. In front of each electrode, an ion-exchange membrane is positioned, and between them, a spacer is situated, which transports the water to be desalinated. In this work, we demonstrate for the first time that up to 83% of the energy used for charging the electrodes during desalination can be recovered in the regeneration step. This can be achieved by charging and discharging the electrodes in a controlled manner by using constant current conditions. By implementing energy recovery as an integral part of the MCDI operation, the overall energy consumption can be as low as 0.26 (kW·h)/m3 of produced water to reduce the salinity by 10 mM, which means that MCDI is more energy efficient for treatment of brackish water than reverse osmosis. Nevertheless, the measured energy consumption is much higher than the thermodynamically calculated values for desa...

284 citations


Journal ArticleDOI
TL;DR: Molecular layer-by-layer (mLbL) assembled thin-film composite membranes fabricated by alternating deposition of reactive monomers on porous supports exhibit both improved salt rejection and enhanced water flux compared to traditional reverse osmosis membranes prepared by interfacial polymerization.
Abstract: Molecular layer-by-layer (mLbL) assembled thin-film composite membranes fabricated by alternating deposition of reactive monomers on porous supports exhibit both improved salt rejection and enhanced water flux compared to traditional reverse osmosis membranes prepared by interfacial polymerization. Additionally, the well-controlled structures achieved by mLbL deposition further lead to improved antifouling performance.

264 citations


Journal ArticleDOI
TL;DR: In this paper, a commercial polyamide reverse osmosis (RO) membrane was surface modified with polydopamine deposited from buffered, aqueous dopamine solution at ambient conditions.

261 citations


Journal ArticleDOI
TL;DR: In this article, the authors investigated the membrane fouling behavior in forward osmosis under conditions simulating the osmotic dilution process and the use of hydrodynamic methods without using any cleaning chemicals.

231 citations


Journal ArticleDOI
TL;DR: In this article, the state-of-the-art developments and breakthrough in the surface modified and nanoparticles incorporated polyamide thin film composite (PA-TFC) reverse osmosis (RO) membranes are focused and summarized combining with the prospects.

215 citations


Journal ArticleDOI
Samer Adham1, Altaf Hussain1, Joel Minier Matar1, Raul Dores1, Arnold Janson1 
TL;DR: In this article, the feasibility of using Membrane Distillation (MD) technology to desalinate brines from thermal desalination plants was evaluated and the performance of different MD membranes was compared under various operating conditions using synthetic saline solutions and seawater from the Arabian Gulf.

204 citations


Journal ArticleDOI
TL;DR: The economics of membrane distillation and common seawater desalination methods including multi effect distillation (MED), multistage flash (MSF) and reverse osmosis (RO) are compared in this paper.

197 citations


Journal ArticleDOI
TL;DR: In this article, switchable polarity solvents (SPS), mixtures of carbon dioxide, water, and tertiary amines, are presented as viable forward osmosis (FO) draw solutes allowing a novel SPS FO process.

197 citations


Journal ArticleDOI
TL;DR: Nanofiltration (NF) is one of the widely used membrane processes for water and wastewater treatment in addition to other applications such as desalination as mentioned in this paper, which has replaced reverse osmosis (RO) membranes in many applications due to lower energy consumption and higher flux rates.
Abstract: . The application of membrane technology in water and wastewater treatment is increasing due to stringent water quality standards. Nanofiltration (NF) is one of the widely used membrane processes for water and wastewater treatment in addition to other applications such as desalination. NF has replaced reverse osmosis (RO) membranes in many applications due to lower energy consumption and higher flux rates. This paper briefly reviews the application of NF for water and wastewater treatment including fundamentals, mechanisms, fouling challenges and their controls.

172 citations


Journal ArticleDOI
TL;DR: In this paper, the authors systematically investigated membrane fouling by organic foulants in pressure retarded osmosis (PRO) process and its effect on PRO power density, and found that significant alginate fouling occurred when the draw solution (DS) contained large quantities of divalent cations.

Journal ArticleDOI
TL;DR: In this paper, the authors investigated the scaling and cleaning behavior in forward osmosis (FO) and how it compared with that in reverse osmotic (RO) modes, and found that the flux decline rates under silica scaling are very similar in the two modes, but the flux recovery is close to 100% in the FO mode while it is only around 80% in RO mode.

Journal ArticleDOI
TL;DR: In this paper, the rejection of trace organic contaminants (TrOCs) by an osmotically driven membrane filtration process was investigated and compared under three different operating modes: forward osmosis (FO), pressure-retarded Osmosis, and reverse ossification (RO), and the results revealed that the cellulose acetate membrane had considerably smaller water and salt permeabilities as well as less negative surface charge compared to the NF membrane.

Journal ArticleDOI
TL;DR: In this article, the authors proposed a hybrid desalination system that combines reverse electrodialysis (RED) and reverse osmosis (RO) processes, where the RED unit harvests the energy in the form of electricity from the salinity gradient between a highly concentrated solution (e.g., seawater or concentrated brine) and a low salinity solution (i.e., biologically treated secondary effluent or impaired water).

Journal ArticleDOI
TL;DR: In this paper, the influence of membrane properties, draw solution (DS) properties, feed solution (FS) properties and operating conditions on the performance of forward osmosis (FO) desalination was evaluated.

Journal ArticleDOI
TL;DR: In this article, a pressure retarded osmosis (PRO) energy recovery is used for energy-saving and defusing the environmental impact caused by concentrated brine in the mega-ton water system.

Journal ArticleDOI
TL;DR: The N-Free(®) technology demonstrated to be a valuable candidate for the path toward nutrient and water recycle, in a new sustainable agriculture and farming concept.

Journal ArticleDOI
TL;DR: The results showed that the incorporation of carbon filler particles in polymer hydrogels led to enhanced swelling ratios of the draw agents and thus higher water fluxes in the FO process.


Journal ArticleDOI
Hai Huang1, Xinying Qu1, Hang Dong1, Lin Zhang1, Huanlin Chen1 
TL;DR: In this paper, the behavior and role of NaA nanozeolites during an interfacial polymerization process towards a polyamide thin-film nanocomposite (TFN) reverse osmosis membrane by incorporating nanoZEolites into two different reactive phases was explored.
Abstract: This paper explores the behaviour and role of NaA nanozeolites during an interfacial polymerization process towards a polyamide thin film nanocomposite (TFN) reverse osmosis membrane by incorporating nanozeolites into two different reactive phases. In the two cases, the different interactions occurring between the zeolites and polyamide were investigated by FT-IR spectra, XPS analysis, and examining the membrane morphology and the desalination performance. The polyamide TFN membrane with an increased degree of cross-linking was obtained with nanozeolites in the organic phase, as the NaA zeolite reacted with the acyl chloride monomer in the organic phase. Additionally, the membrane with nanozeolites added to the organic phase had a superior reverse osmosis performance, since the porous zeolite appeared in the top layer as a water channel.

Journal ArticleDOI
TL;DR: In this article, the performance of forward osmosis (FO) at the pilot scale to achieve simultaneous seawater desalination and wastewater reclamation was evaluated with a commercial spiral wound FO membrane element for approximately 1300h of continuous operation.

Journal ArticleDOI
TL;DR: In this paper, the authors reviewed the history of desalination and present trends in water pre-treatment and integrated membrane systems and highlighted the future prospects for integrated desalification techniques which could result in reduction of cost of desali...
Abstract: The Gulf countries are located in the arid and semi-arid regions where rainfall is scanty and evaporation rates are high. Surface water is limited and there are no perennial streams. The increase in population and socio-economic development has led to an imbalance between supply and demand. These countries depend mainly on desalination to meet the growing water needs. This paper reviews the history of desalination and the desalination processes used—multistage flash distillation (MSF), reverse osmosis (RO), multieffect distillation and electrodialysis. An overview of these processes and the challenges faced—like scaling of tubes in MSF and membrane fouling in RO—is discussed. This review also highlights the present trends in water pre-treatment and integrated membrane systems. The depletion of fossil fuels makes it imperative to consider alternate energy sources like solar and nuclear energy. Future prospects for integrated desalination techniques which could result in reduction of cost of desali...

Journal ArticleDOI
Jun Xu1, Zhi Wang1, Linling Yu1, Jixiao Wang1, Shichang Wang1 
TL;DR: In this paper, a commercial aromatic polyamide RO membrane (RE4021-TL, Woongjin Chemical Co., Ltd.) is improved by carbodiimide-induced grafting with imidazolidinyl urea (IU).

Journal ArticleDOI
TL;DR: In this article, a poly(piperazinamide) or polyamide selective layer formed by interfacial polymerization on top of a nylon 6,6 microfiltration membrane support was used to increase the wetted porosity and to mitigate internal concentration polarization.

Journal ArticleDOI
TL;DR: In this paper, surface modification of a commercial TFC RO membrane was performed through redox initiated graft polymerization of N-isopropylacrylamide (NIPAm) followed by acrylic acid (AA) and the modified membrane showed improved membrane properties.

Journal ArticleDOI
TL;DR: The most promising technology to desalinate seawater is reverse osmosis (RO), which is experiencing significant growth as discussed by the authors, and remarkable advances have been made in the preparation of RO membranes from different materials.

Journal ArticleDOI
TL;DR: In this paper, the effect of membrane orientation on fouling behavior of forward osmosis (FO) membrane operated in FO mode (i.e., the dense layer facing the feed solution) and pressure-retarded (PRO) mode was investigated, and the results revealed that the FO membrane fouled more easily than when operated in the PRO mode and the fouling became more severe with increasing organic concentration in the feed solutions.

Journal ArticleDOI
TL;DR: In this article, the authors show that pristine graphyne, one of the graphene-like one-atom-thick carbon allotropes, can achieve 100% rejection of nearly all ions in seawater including Na(+, Cl(-), Mg(2+), K(+) and Ca(2+) at an exceptionally high water permeability about two orders of magnitude higher than those for commercial state-of-the-art reverse osmosis membranes at a salt rejection of ~98.5%.
Abstract: Desalination that produces clean freshwater from seawater holds the promise of solving the global water shortage for drinking, agriculture and industry. However, conventional desalination technologies such as reverse osmosis and thermal distillation involve large amounts of energy consumption, and the semipermeable membranes widely used in reverse osmosis face the challenge to provide a high throughput at high salt rejection. Here we find by comprehensive molecular dynamics simulations and first principles modeling that pristine graphyne, one of the graphene-like one-atom-thick carbon allotropes, can achieve 100% rejection of nearly all ions in seawater including Na(+), Cl(-), Mg(2+), K(+) and Ca(2+), at an exceptionally high water permeability about two orders of magnitude higher than those for commercial state-of-the-art reverse osmosis membranes at a salt rejection of ~98.5%. This complete ion rejection by graphyne, independent of the salt concentration and the operating pressure, is revealed to be originated from the significantly higher energy barriers for ions than for water. This intrinsic specialty of graphyne should provide a new possibility for the efforts to alleviate the global shortage of freshwater and other environmental problems.

Journal ArticleDOI
TL;DR: In this article, modified UF and RO membrane modules were used to remove most of the highly fouling organic matter in the feed before desalination by a train of RO elements.

Journal ArticleDOI
TL;DR: In this paper, a review on the membrane methods recently introduced into the nuclear technology against the background of the other commonly applied separation techniques, with indications of the possibilities and prospects for their further developments.