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Preparing an Appropriate UF Membrane from PVC to Use it as Substrate in Sea Water Desalination RO Membranes
, M.Sc. Thesis Sharif University of Technology ; Bastani, Daruoosh (Supervisor) ; Musavi, Abbas (Supervisor)
Abstract
In this study the main goal is preparing an appropriate UltraFiltration membrane from PolyVinyl Chloride for using as substrate in producing efficient Reverse Osmosis membranes to use in sea water desalination. each membrane should have some specifications to use it as reverse osmosis membrane’s substrate. One of the most important specifications is the appropriate pore sizes. To investigate this subject pure water flux and PolyEthylene glycol rejection of prepared membranes is tested. After investigation of this parameters and proving them, RO membranes are prepared using this membranes.
Salt rejection of Brackish water (2000ppm) and sea water (Persian gulf,32000ppm) are measured in...
Salt rejection of Brackish water (2000ppm) and sea water (Persian gulf,32000ppm) are measured in...
Biofouling Reduction in Reverse Osmosis Membrane for the Purification Brackish Water
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor) ; Mousavi, Abbas (Supervisor)
Abstract
In this project, modification of reverse osmosis membrane was investigated in order to reduce the biofouling in treatment of brackish water. Furthermore, the technique which is used to attain the favorable results is graft polymerization to modify the membrane’s surface with grafting acrylic acid as hydrophilic monomer onto polyamide exploited as last layer in reverse osmosis membrane. This technique is a free radical grafting, andfree radicals which are needed for grafting are provided by the redox system potassium persulfate-sodium metabisulfite which was used as initiator. To figure out the best concentration of acrylic acid, initiator and process time in order to achieve a new membrane...
Treatment of Blow-down water to Reuse by Membrane Processes, Nanofiltration and Reverse Osmosis
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor)
Abstract
Petrochemicals, refineries and power plants are among the biggest water-consuming industries. Of all systems in mentioned complex, most water is consumed in the cooling tower system, of which the feed water of the cooling tower accounts for the largest portion of water demand. Drainage loss (blowdown) which constitutes the biggest portion of the feed water losses, varies greatly with changes in source water quality and cooling water treatment. Scarcity of water, large quantities of cooling tower blowdown water and increasing of water price lead to activities for blowdown water treatment to reuse. In this project two pre-treatment methods and two final membrane treatment methods were...
Design, Construction and Experimental Study of Effect of a Pressure Intensifier Device on a Small Scale Reverse Osmosis System
, M.Sc. Thesis Sharif University of Technology ; Arghavani Hadi, Jamal (Supervisor)
Abstract
Nowadays, water and energy shortage is the main concern of many industries. Every saving that could be done is valuable. In the first step of this project, energy recovery devices that are used in reverse osmosis systems, are reviewed and advantages and disadvantages of each system are investigated. These apparatuses save energy by recovering high-pressure energy from leaving brine and reduce the energy consumption of the device. The main focus of this study is energy consumption of the device that is used for desalination of seawater in reverse osmosis systems and on this basis, different energy recovery devices are compared. According to the investigation, results showed that most of the...
Effect of Electromagnetic Field on Membrane Fouling in Filtration Process
, M.Sc. Thesis Sharif University of Technology ; Kariminia, Hamid Reza (Supervisor) ; Mousavi, Abbas (Supervisor)
Abstract
Current research studies the effect of electromagnetic field on reducing precipitation on membrane surface in reverse osmosis. Reverse osmosis is one of the most widely applied methods for water desalinization. Despite its advantages over other desalinization techniques, suffers from shortcomings such as blockage of membrane surface. Use of magnetic fields for reducing precipitation in process equipment, the so-called magnetic treatment, has been studied and practiced for decades. This research intends to study the effect of electromagnetic field on water and its mineral content, and the possibility of its application as a method for reducing precipitation and blockage in reverse osmosis...
Waste Water Purification of the Isfahan Zirconium Production Plant (ZPP) by Membrane Process
, M.Sc. Thesis Sharif University of Technology ; Samad Fam, Mohammad (Supervisor) ; Yavari, Ramin (Supervisor) ; Haji Hosseini, Majid (Co-Supervisor)
Abstract
Isfahan Zirconium Production Plant (ZPP) is one of the most important plants in the nuclear industry of Islamic Republic of Iran. The wastewater of this plant contains high values of Sodium, Chloride, Nitrate and low values of Calcium, Magnesium, Zinc and Zirconium ions. Its release has been banned by international and national law because of the dangers and toxicity of its ions for the environment and living organisms. Therefore, its refinement as a compensation of Iran’s water resources in agriculture and drinking water has received a major consideration. Among the common methods to removal of these ions, membrane process method is selected due to it's major benefits such as not producing...
Forward Osmosis in High Saline Water Desalination
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor) ; Musavi, Abbas (Supervisor)
Abstract
Due to population growth, per capita change and heterogeneous distribution of water resources, forecasts demonstrate that more than 66% of the world's population will experience water scarcity by 2025. The major concern of desalination is their management of brine, with concentrations and their associated components more than twice the input concentration. Also, when extracting oil, per 1 oil barrel, about 7 to 10 barrels of high saline water are produced. One of the most common methods for disposing of brine is direct discharge into the environment, which, due to its destructive effects, creates serious threats to marine ecosystems. Therefore, it is necessary to desalting these high saline...
Modification of the GV-MSA model in obtaining the activity and osmotic coefficients of aqueous electrolyte solutions
, Article Fluid Phase Equilibria ; Volume 240, Issue 2 , 2006 , Pages 167-172 ; 03783812 (ISSN) ; Taghikhani, V ; Ghotbi, C ; Sharif University of Technology
2006
Abstract
In this work a modified form of the Ghotbi-Vera Mean Spherical Approximation model (MGV-MSA) has been used to correlate the mean ionic activity coefficients (MIAC) for a number of symmetric and asymmetric aqueous electrolyte solutions at 25 °C. In the proposed model the hard sphere as well as the electrostatic contributions to the MIAC and the osmotic coefficient of the previously GV-MSA model has been modified. The results of the proposed model for the MIAC of the electrolyte solutions studied in this work are used to directly calculate the values of the osmotic coefficients without introducing any new adjustable parameter. In the MGV-MSA model the cation diameter as well as the relative...
The effect of variable catalyst loading in electrodes on PEM fuel cell performance
, Article 3rd International Conference on Fuel Cell Science, Engineering, and Technology, 2005, Ypsilanti, MI, 23 May 2005 through 25 May 2005 ; 2005 , Pages 145-152 ; 0791837645 (ISBN); 9780791837641 (ISBN) ; Farhanieh, B ; Sharif University of Technology
American Society of Mechanical Engineers
2005
Abstract
Catalyst layers are one the important parts of the PEM fuel cells as they are the main place for electrochemical reaction taking place in anode and cathode of the cells. The amount of catalyst loading of this layer has a large effect on PEM fuel cell performance. Non-uniformity of reactant concentration could lead to a variation of current density in anode and cathode catalyst layer. The main reason for this phenomenon is porosity variation due to two effects: 1. compression of electrode on the solid landing area and 2. Water produced at the cathode side of diffusion layer. In this study the effect of variable current density in anode and cathode electrode on cell performance is...
On the design of graphene oxide nanosheets membranes for water desalination
, Article Desalination ; Volume 422 , 2017 , Pages 83-90 ; 00119164 (ISSN) ; Tavakoli, R ; Sharif University of Technology
Elsevier B.V
2017
Abstract
According to current researches, graphene oxide (GO) membranes show promising desalination properties due to ease of synthesis, low production cost, and high efficiency. There are several experimental works to study ionic sieving properties of GO membranes. However, it is difficult to characterize atomistic mechanism of water permeation and ion rejection by experimental approaches. On the other hand, there exist a few reports in which the atomistic picture of water permeation across GO membranes is investigated by means of molecular dynamics (MD) simulation. In the present work, in addition to water desalination, the atomic scale mechanism of ion rejection is studied using large scale MD...
Enhancement of surface properties and performance of reverse osmosis membranes after surface modification: a review
, Article Desalination ; Volume 420 , 2017 , Pages 330-383 ; 00119164 (ISSN) ; Bastani, D ; Musavi, S. A ; Sharif University of Technology
Abstract
Reverse osmosis (RO) membrane process has become the most promising technology for desalination to produce purified water. Among numerous polymeric materials used to fabricate RO membranes, aromatic polyamide thin film composite (TFC) membranes are dominant in commercial RO membrane processes because of their high salt rejection and water permeability as well as their excellent chemical, thermal, and mechanical stability. However, the major hindrance to the effective application of polyamide TFC RO membranes is membrane fouling. Furthermore, polyamide TFC RO membranes have limited stability to chlorine, which is commonly used as disinfect to control membrane biofouling. These two factors...
Preparation of poly(vinyl chloride) (PVC) ultrafiltration membranes from PVC/additive/solvent and application of UF membranes as substrate for fabrication of reverse osmosis membranes
, Article Journal of Applied Polymer Science ; Volume 135, Issue 21 , 2018 ; 00218995 (ISSN) ; Asadollahi, M ; Musavi, A ; Bastani, D ; Sharif University of Technology
John Wiley and Sons Inc
2018
Abstract
Ultrafiltration (UF) membranes were prepared from poly(vinyl chloride) (PVC) as main polymer, poly(vinyl pyrrolidone) (PVP) as additive, and 1-methyl-2-pyrrolidone (NMP) as solvent using Design Expert software for designing the experiments. The membranes were characterized by SEM, contact angle measurement, and atomic force microscopy. The performance of UF membranes was evaluated by pure water flux (PWF) and blue indigo dye particle rejection. In addition, the molecular weight cutoff of UF membranes was determined by poly(ethylene glycol) (PEG) rejection. The UF membranes were used as substrates for fabrication of polyamide thin film composite (TFC) reverse osmosis (RO) membranes. The...
Modeling and techno-economic study of a solar reverse osmosis desalination plant
, Article International Journal of Environmental Science and Technology ; Volume 19, Issue 9 , 2022 , Pages 8727-8742 ; 17351472 (ISSN) ; Hajialigol, P ; Boroushaki, M ; Shafii, M. B ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
In this research, the design of a solar reverse osmosis desalination plant was investigated by integrating various components using TRNSYS and ROSA software. To this goal, a two-stage reverse osmosis system with 50% recovery in the city of Chabahar was modeled. The calculations were performed in three different case studies, i.e., a photovoltaic power plant, a solar collector power plant with Organic Rankine Cycles, and a photovoltaic thermal power plant with Organic Rankine Cycles, with the reverse osmosis desalination plant being a novel investigation. Water production and electrical energy generation of each case study were evaluated both on a daily and yearly bases. The simulation...
A new flat sheet membrane bioreactor hybrid system for advanced treatment of effluent, reverse osmosis pretreatment and fouling mitigation
, Article Bioresource Technology ; Volume 192 , 2015 , Pages 177-184 ; 09608524 (ISSN) ; Bidhendi, G. N ; Torabian, A ; Mehrdadi, N ; Pourabdullah, M ; Sharif University of Technology
Abstract
This paper introduces a new hybrid electro membrane bioreactor (HEMBR) for reverse osmosis (RO) pretreatment and advanced treatment of effluent by simultaneously integrating electrical coagulation (EC) with a membrane bioreactor (MBR) and its performance was compared with conventional MBR. Experimental results and their statistical analysis showed removal efficiency for suspended solids (SS) of almost 100% for both reactors. HEMBR removal of chemical oxygen demand (COD) improved by 4% and membrane fouling was alleviated according to transmembrane pressure (TMP). The average silt density index (SDI) of HEMBR permeate samples was slightly better indicating less RO membrane fouling. Moreover,...
Monitoring & Optimizing of the Returned Condensated Water as Boiler Make up Water at the Agro-Industry Hakim Farabi Boilers
, M.Sc. Thesis Sharif University of Technology ; Alamolhoda, Ali Asghar (Supervisor) ; Pourjavadi, Ali (Co-Advisor)
Abstract
Vapor in agro-industry hakim farabi production electricity, Turbines force and thermal energy for Yellow and white sugar in sugar production. In the utilization to supply water for the boiler , condensate water return use Until plant be able to do its work ¬good quality of condensate water decrease cost of destruction energy in blow down and can save energy, reduce cost of chemical operation for optimum boiler water and costs associated with wastewater treatment. unclean condensate water consist of sugar and Electrical conductivity more than permissive is not suitable for use in The boiler because Increase the total dissolved solids and decreasing pH lower than the Extent permitted. The...
Water Recycling from Output Residual Flow of Reverse Osmosis Membranous Units
, M.Sc. Thesis Sharif University of Technology ; Moosavi, Abbas (Supervisor)
Abstract
In this research, we focus on reduction of solutes in left out water from reverse osmosis membranous units (brine) with reduction of scaling factors of membrane. This research is important from that perspective that the out put brine from reverse osmosis membranous unit After purification by this method, enter into membranous system in order to increase in recovered water volume and also minimization of out put waste from membranous system and decrease the environmental damages. The method used in this research, is three processes of cooling, chemical desalination and seeding by crystal material. In this research is investigated the type and amount of matter for chemical desalination and...
Study of Surface Properties and Performance of Reverse Osmosis Membranes after Surface Modification via Irradiation
, Ph.D. Dissertation Sharif University of Technology ; Bastani, Dariush (Supervisor) ; Mousavi, Abbas (Supervisor)
Abstract
Today reverse osmosis (RO) is the dominant technology for desalination. Most of commercially available RO membranes are polyamide thin film composite (TFC) types which exhibit good performance. However, the major obstacle for application of polyamide TFC RO membranes is fouling which can be mitigate by surface modification.In this research, surface modification of fabricated aromatic polyamide TFC RO membranes was carried out using UV-initiated graft polymerization at different irradiation times (15, 30, 60, and 90 s) and various acrylamide concentrations (10, 20, and 30 g/L). Also, coating of membranes surface with various concentrations of TiO2 nanoparticles (10, 20, 30, and 50 ppm)...
Preparation a Polymeric Membrane for Dehydration of Acetic Acid
, M.Sc. Thesis Sharif University of Technology ; Mousavi, Abbas (Supervisor) ; Bastani, Dariush (Supervisor)
Abstract
The separation ofacetic acids in binary water solutions hasbeenstudied using a reverse osmosis (RO) membrane. Thin film composite polyamide membrane is used in this study.Thin-film composite (TFC) membrane was prepared through the interfacial polymerization between m-phenylenediamine (MPD) and trimesoyl chloride (TMC) on the polysulphone support membrane.The solute permeation was carried out under applied pressure of 5 bar at 25°C. In this work the effect of various synthesis conditions on the membrane performance was investigated. Parametric studies were conducted by varyingconcentration of reactants, reaction time, curing time and curing temperature. By suitable combination of these...
Hydrodynamic Simulation of Flow in Reverse Osmosis Membranes for Seawater Disalination
, M.Sc. Thesis Sharif University of Technology ; Seif, Mohamad Saeed (Supervisor) ; Mehdigholi, Hamid (Supervisor)
Abstract
Water is the most essential human need and the lack of fresh water soon is one of the biggest problems of mankind. One way to deal with the lack of fresh water is desalination of seawater. Seawater desalination is done by different thermal and membrane methods. In this research, the methods and history of freshwater supply methods and the role of chains in the progress of seawater desalination, and the measures taken in the field of seawater desalination have been investigated. Among the various methods discussed and proposed in this research, it was concluded that reverse osmosis membrane is available and has an acceptable economic efficiency compared to other methods. After choosing the...
Designing and Modeling of a Hybrid System Based on Electrodialysis for Desalinating Brine
, M.Sc. Thesis Sharif University of Technology ; Moosavi, Ali (Supervisor) ; Hoseini, Vahid (Supervisor)
Abstract
The world's freshwater resources are rapidly decreasing due to population growth, industrial and technological progress, successive droughts, climate changes, increased food demand, and poor management of water resources. Using desalination methods is one of the ways to produce the required freshwater. Several methods have been developed for desalination. The most widely used method is reverse osmosis (RO). In this thesis, an electrodialysis (ED) desalination system was designed and modeled using up-to-date and reliable articles. This modeling was done in EES software and after validating that, the effect of considering Donnan's potential was investigated. At the 60 ppt concentration of the...