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osmosis
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Ro brine treatment and disposal methods
, Article Desalination and Water Treatment ; Volume 35, Issue 1-3 , Aug , 2011 , Pages 39-53 ; 19443994 (ISSN) ; Shahbazali, E ; Sharif University of Technology
Taylor and Francis Inc
2011
Abstract
More than 50 percent of countries in the world will likely face water stress or water shortages by 2025, and by 2050, as much as 75 percent of the world's population could face water scarcity. Desalination technologies, particularly the reverse osmosis (RO) process, have increasingly been adopted to produce freshwater from alternative sources such as seawater and brackish water due to water scarcity. However, desalination applications have always been limited by the disposal costs of RO brine and the adverse impact of brine on the receiving environment. The scope of this paper is to identify technically and commercially RO brine disposal and treatment methods such as deep well injection,...
Interaction effects in multicomponent separation by reverse osmosis
, Article Journal of Membrane Science ; Volume 183, Issue 1 , 2001 , Pages 15-27 ; 03767388 (ISSN) ; Sahebdelfar, S ; Sharif University of Technology
Elsevier
2001
Abstract
Separation of multicomponent mixtures, in particular ternary systems, was investigated theoretically and experimentally. The interactions in various multicomponent mixtures were determined. Using data from literature as well as the limited data obtained in our laboratory, we identified the situations where the multicomponent effects are strong. A correlation between the coupled permeability coefficients and straight permeability coefficients and concentration of components in ternary systems was obtained. Capabilities of thermodynamic models in describing the electrolyte-nonelectrolyte systems consisting of a weak acid were also investigated. The results of this work show that the...
Removal of Surface Defects and Improvement of Properties of Reverse Osmosis Membrane in Water Treatment Process
, M.Sc. Thesis Sharif University of Technology ; Bastani, Dariush (Supervisor) ; Mousavi, Abbas (Supervisor)
Abstract
The purpose of this project is to correct the surface defects of the reverse osmosis membrane. The membrane tested in this project was a thin film made of three layers of polyester, polysulfone and polyamide. These three layers provide mechanical resistance to operating pressure, suitable substrate for polyamide layer synthesis and membrane selectivity, respectively.In order to improve the surface properties and modify the reverse osmosis membrane, it was first attempted to coat it with a protective layer of polyvinyl alcohol, then by modifying this layer and improving the properties of polyvinyl alcohol and synthesizing the sulfite agent on it by the esterification reaction, to the best...
Simulation of wellbore stability with thermo-hydro-chemo-mechanical coupling in troublesome formations: an example from Ahwaz oil field, SW Iran
, Article Arabian Journal of Geosciences ; Volume 8, Issue 1 , 2015 , Pages 379-396 ; 18667511 (ISSN) ; Jalayeri, H ; Ghotbi, C ; Pishvaie, M. R ; Sharif University of Technology
Abstract
Wellbore stability is a main concern in drilling operation. Troublesome drilling issues are chemically active formations and/or high-pressure–high-temperature environments. These are mainly responsible for most of wellbore instabilities. Wellbore failure is mostly controlled by the interaction between active shales and drilling fluid in shale formations. The factors influencing this interaction consist of fluid pressure, temperature, composition of drilling fluid, and exposure time. In this paper, a non-linear fully coupled chemo-thermo-poroelasticity model is developed. At first, a fully implicit finite difference model is presented to analyze the problem, and then, it is verified through...
Recovery of cooling tower blowdown water for reuse: the investigation of different types of pretreatment prior nanofiltration and reverse osmosis
, Article Journal of Water Process Engineering ; Volume 10 , 2016 , Pages 188-199 ; 22147144 (ISSN) ; Borghei, S. M ; Vatanpour, V ; Sharif University of Technology
Abstract
The suitability of two different pretreatment methods, i.e., coagulation-filtration and ultrafiltration (UF), and two final membrane treatment technologies, namely nanofiltration (NF) and reverse osmosis (RO), for desalination of a cooling tower blowdown (CTBD) was investigated. Particular attention was paid to ensuring that the best pretreatment method could enhance the permeate flux and lifespan of the NF and RO membranes and decrease the membranes' fouling characteristics. Furthermore, the difference of NF and RO performances in CTBD treatment was investigated. In order to find the most appropriate type of coagulant, coagulant dosage, pH and co-coagulant dosage, 21 jar tests were...
Preparation of mesh-reinforced cellulose acetate forward osmosis membrane with very low surface roughness
, Article Korean Journal of Chemical Engineering ; Volume 34, Issue 12 , 2017 , Pages 3170-3177 ; 02561115 (ISSN) ; Mousavi, S. A ; Ramazani Saadat Abadi, A ; Sadeghi, M ; Sharif University of Technology
Abstract
Mesh-reinforced cellulose acetate (CA)-based membranes were prepared for forward osmosis (FO) by immersion precipitation. Casting compositions such as CA percent and 1, 4-dioxane/acetone ratio and also preparation conditions such as evaporation time, coagulation bath and annealing temperatures were tested for membranes’ performance. The results were compared with commercially CTA membranes. The best membrane (17.9% polymer and 1, 4-dioxane/acetone ratio of 1.89) showed water flux of 9.3 L/m2h (LMH) and RSF of 0.536 mol NaCl/m2h. Moreover, the membrane structure was reinforced by a polyester mesh, which created micro pores in the back of the membrane. This caused higher water flux and RSF...
Optimum design of R.O. membrane by using simulation techniques
, Article Desalination and Water Treatment ; Volume 9, Issue 1-3 , 2009 , Pages 189-194 ; 19443994 (ISSN) ; Ehteshami, M ; Ardakanian, R ; Sharif University of Technology
2009
Abstract
Increasing demand of fresh water, and limitation water resources, with respect to world economic growth brings up the importance of utilization of saline water. At the current research the sensitivity analysis of ROSA was conducted. For this analysis, a single stage reverse osmosis is designed for well water specifi cation in southern Tehran under following condition: Feed fl ow: 40 m3/h and membrane Element: BW30–400 FR. The sensitivity analyses for all chemical element of base water were performed. As a result of sensitivity analysis shortest sensitivity gap, belongs to boron, and longest sensitivity gap, belongs to calcium. Which refl ects, under the same conditions, the least element to...
Enhance the Chlorine Resistance of Reverse Osmosis Membrane
, M.Sc. Thesis Sharif University of Technology ; Mousavi, Abbas (Supervisor) ; Abdekhodaei, Mohammad Jafar (Supervisor)
Abstract
Reverse osmosis membrane one of the common methods used for water desalination, today membrane, thin film composite(TFC) include three layers, top the these layers named selection layer, this poly amid layer contacted with feed water, sensitivity to chlorine in polyamide layer lead to high membrane chlorine sensitive. Difference methods used for enhance the chlorine resistance in polyamide membrane that categorized in three general categories, covering and protection of sensitive areas method has best results in comparison to other methods. In this research protection method choose and used, material that used, sanitized by result from surface analysis of commercial membrane manufactured in...
Design of a Desalination System with High Recovery Using Membrane Based Systems
, M.Sc. Thesis Sharif University of Technology ; Mousavi, Ali (Supervisor) ; Nouri Borujerdi, Ali (Supervisor)
Abstract
Osmotically assisted reverse osmosis (OARO) assimilates high efficiency due to non-thermal processes and accessing high salinity. This makes it suitable for high water recovery for the purpose of zero- and minimal liquid discharge desalination. Moreover, forward osmosis (FO) has low fouling efficiency which makes the operating costs of cleaning and replacement lower. This study aims at incorporating OARO and FO in a novel configuration with multiple inlet of the diluted draw solution to the regeneration section. Pinch analysis with simplifying assumptions was carried out for FO and OARO standalone stages. The results showed that pinch point in FO resides either on the beginning or at the end...
GAMS based approach for optimal design and sizing of a pressure retarded osmosis power plant in Bahmanshir river of Iran
, Article Renewable and Sustainable Energy Reviews ; Volume 52 , 2015 , Pages 1559-1565 ; 13640321 (ISSN) ; Abbaspour, M ; Mohammadi-Ivatloo, B ; Bakhtari, K ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Osmotic power generation is one of the cleaner and sustainable methods for energy generation. This paper presents a study on the optimal size and design of pressure retarded osmosis (PRO) power plant as a viable source of renewable energy in the selected site in Bahmanshir river of Iran. The optimal sizing and design problem is formulated as a Non-Linear Programming (NLP) optimization problem and solved using the standard optimization software titled generalized algebraic modeling system (GAMS). The objective function is minimizing the total cost while considering the technical and economic constraints. Optimization results show that the optimal capacity of the PRO osmotic power plant is...
Modelling and economic evaluation of pressure-retarded osmosis power plant case study: Iran
, Article International Journal of Ambient Energy ; 2017 , Pages 1-13 ; 01430750 (ISSN) ; Abbaspour, M ; Sharif University of Technology
Abstract
In recent years, a growing interest in investigation of new energies has been observed. Pressure-retarded osmosis (PRO) could be a feasible source of renewable energy. This study aims to present a model based on the present technology of PRO power plant components for design and economic evaluation of a PRO power plant, and to investigate case studies in order to demonstrate how each main component of a PRO power plant affects the economic evaluation. Therefore, all the mechanisms including intake and outfall systems, pre-treatment system, membrane system, and transportation and generation systems are explicated and meant to present the capability of the model to design the PRO power plant....
Ultrahigh permeable C2N-inspired graphene nanomesh membranes versus highly strained c2n for reverse osmosis desalination
, Article Journal of Physical Chemistry B ; Volume 123, Issue 41 , 2019 , Pages 8740-8752 ; 15206106 (ISSN) ; Akhavan, O ; Sharif University of Technology
American Chemical Society
2019
Abstract
The reverse osmosis (RO) desalination capability of hydrogenated and hydroxylated graphene nanomesh membranes (GNMs) inspired by the morphology of carbon nitride (C2N) has been studied by using molecular dynamics simulation. As an advantage, water permeance of the GNMs is found to be several orders of magnitude higher than that of the available RO filters and comparable with highly strained C2N (S-C2N) as follows: 6,6-H,OH > 12-H > S-C2N > 5,5-H,OH > 10-H. The reverse order is found for salt rejection, regardless of S-C2N. The hydrophilic character of the incorporated -OH functional group is believed to be responsible for linking the water molecules in feed and permeate sides via the...
Modelling and economic evaluation of pressure-retarded osmosis power plant case study: Iran
, Article International Journal of Ambient Energy ; Volume 40, Issue 1 , 2019 , Pages 69-81 ; 01430750 (ISSN) ; Abbaspour, M ; Sharif University of Technology
Taylor and Francis Ltd
2019
Abstract
In recent years, a growing interest in investigation of new energies has been observed. Pressure-retarded osmosis (PRO) could be a feasible source of renewable energy. This study aims to present a model based on the present technology of PRO power plant components for design and economic evaluation of a PRO power plant, and to investigate case studies in order to demonstrate how each main component of a PRO power plant affects the economic evaluation. Therefore, all the mechanisms including intake and outfall systems, pre-treatment system, membrane system, and transportation and generation systems are explicated and meant to present the capability of the model to design the PRO power plant....
Synthesis of Ultra-Low Pressure Reverse Osmosis (ULPRO) Membrane
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor) ; Mousavi, Abbas (Co-Advisor)
Abstract
The aim of this project is to achieve a semi permeable high flux membrane with a reasonable salt rejection for the treatment of low osmotic pressure water. A thin film composite membrane consists of three polymeric layers was studied in this project. These layers were polyester support, polysulfone sub layer and polyamine selective layer. The polyester support provides the mechanical resistance against the operating pressure. The polysulfone sub layer provides the suitable area for polyamide synthesize, and the polyamide layer is the selective active layer of membrane.
The resistance to water penetration in sub layer was reduced first and then, the pores in the polyamide layer refined by...
The resistance to water penetration in sub layer was reduced first and then, the pores in the polyamide layer refined by...
Techno-economic feasibility of a solar-powered reverse osmosis desalination system integrated with lithium battery energy storag
, Article Desalination and Water Treatment ; Volume 167 , 2019 , Pages 57-74 ; 19443994 (ISSN) ; Abbasi Godarzi, A ; Sharif University of Technology
Desalination Publications
2019
Abstract
Today, energy and fresh water play a vital role in human life and the development of economics and also in industry. The energy density in water desalination process is remarkable, so using the renewable energy sources for this purpose can be interesting especially in the high potential renewable energy sources (solar energy) like Middle East. The simulation and feasibility study of solar water desalination system coupled with lithium battery energy storage is considered in the case study of Iran. For these purposes, a complete simulation of the considered system is done. Then, using simulation results, the economic study is carried out using tem economic method. Also, the parametric study...
Application of the Pitzer and the MSA-based models in predicting the activity and the osmotic coefficients of aqueous electrolyte solutions
, Article Scientia Iranica ; Volume 12, Issue 3 , 2005 , Pages 280-289 ; 10263098 (ISSN) ; Ghotbi, C ; Taghikhani, V ; Sharif University of Technology
Sharif University of Technology
2005
Abstract
The GV-MSA, the BMCSL-MSA and the Pitzer models were used to correlate the individual, the mean ionic activity coefficients and the osmotic coefficients of symmetric and asymmetric electrolyte solutions. In order to compare the results obtained from the GV-MSA with those obtained from the Pitzer and the BMCSL-MSA models, the same experimental data and the same minimization procedure were used and the new sets of parameters for the BMCSL-MSA and the Pitzer models were also reported. The values for the osmotic coefficients of electrolyte solutions were calculated directly using the values of the mean ionic activity coefficients obtained from the models studied in this work. The results for the...
Forward Osmosis Membrane Preperation for Seawater Desalination
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor) ; Mousavi, Abbas (Co-Advisor)
Abstract
One of the encouraging technologies for resolving the lack of clean water in the world is forward osmosis process (FO). Reaching to a optimized development of FO membranes is essential to make fo process commercially viable.
This study’s aim is to develop a thin film composites (TFC) membrane with high FO performance (good water flux and high salt rejection) in order to seawater desalination.
Polyacrylonitrile (PAN), a hydrophilic polymer, is a less considered polymer in fabricating support layer for TFC FO membranes .TFC membranes consist of a selective polyamide active layer formed by interfacial polymerization on top of a support layer fabricated by non-solvent induced phase...
This study’s aim is to develop a thin film composites (TFC) membrane with high FO performance (good water flux and high salt rejection) in order to seawater desalination.
Polyacrylonitrile (PAN), a hydrophilic polymer, is a less considered polymer in fabricating support layer for TFC FO membranes .TFC membranes consist of a selective polyamide active layer formed by interfacial polymerization on top of a support layer fabricated by non-solvent induced phase...
Thin-film nanocomposite forward osmosis membranes modified with Zr-based metal–organic framework to improve desalination performance
, Article Applied Organometallic Chemistry ; Volume 34, Issue 2 , 2020 ; Bayrami, A ; Amini, M ; Sharif University of Technology
John Wiley and Sons Ltd
2020
Abstract
In present work, first, the water-stable metal–organic framework (MOF) nanocrystals, UiO-66-(F)4, were synthesized under green reaction condition and then some PES/PA thin-film nanocomposite (TFN) membranes were prepared using this synthesized nanocrystals (as modifier) and polyethersulfone (as the substrate). The obtained MOF and membranes were characterized by various characterization techniques such as FE-SEM, AFM, PXRD, contact angle measurements and FT-IR spectroscopy. Finally, the forward osmosis performance of the resultant membranes was evaluated by using different concentrations of NaCl as a draw solution and deionized water as a feed solution. Among all used membranes, the membrane...
A feasibility study of solar-powered reverse osmosis processes
, Article Desalination ; 2020 ; Shirvani, H ; Alamolhoda, A. A ; Farhadi, F ; Karimi, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
The use of solar-powered reverse osmosis desalination systems is a sustainable and environmentally friendly solution in the desalination industry. However, there are some substantial technical and economic challenges due to the intermittency and fluctuation of solar energy. Recent technological improvement and feed-in tariff policies enable these systems to be competitive with conventional grid-connected reverse osmosis systems. In this paper, a feasibility study of the integration of solar panels with the grid to power small-scale reverse osmosis systems (namely up to 2000 m3/day) is conducted in Iran, as a country with a low price of electricity. For this purpose, a city located on the...
High-performance thin-film nanocomposite (TFN) forward osmosis (FO) membranes incorporated with porous hydrophobic-core/hydrophilic-shell nanoparticles
, Article Desalination ; Volume 515 , 2021 ; 00119164 (ISSN) ; Bayrami, A ; Shekari, Z ; Amini, M ; Sharif University of Technology
Elsevier B.V
2021
Abstract
The current article discusses some unprecedented information about the improvement in forward osmosis (FO) performance of polyethersulfone/polyamide (PES/PA) membranes, mainly focused on water flux and selectivity along with resistance to fouling phenomenon; which itself is brought in by the introduction of pre-modified zeolitic imidazolate framework-8 MOF nanoparticles. An investigation has been conducted on ZIF-8 nanoparticles surface with hydrophilicity feature to evaluate their potential for utilization in active polyamide layer of FO membranes for the first time, free from any decrease in water flux value (when hydrophobic ZIF-8 is exploited solely) and selectivity (when mSiO2 with...