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desalination
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Water desalination by charged multilayer graphene membrane: A molecular dynamics simulation
, Article Journal of Molecular Liquids ; Volume 355 , 2022 ; 01677322 (ISSN) ; Moosavi, A ; Nouri Borujerdi, A ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Graphene, due to its unique excellent properties, is proposed as a developing method with high efficiency compared to classical water desalination methods. In this regard, charging the membrane is considered a promising and effective approach to enhance the performance of the graphene membrane. In this research, by using molecular dynamics simulations, the water desalination by charged multilayer graphene is evaluated and the influence of electric charge amount and geometric parameters, including the pore diameter and the interlayer distance, are investigated. According to the results, the multilayer nanoporous graphene with 16.35 Å pore diameter, in which the electric charge is distributed...
Exergy and Thermoeconomic Analysis of a Hybrid System of Desalination and CCHP, Augmented by Solar Energy
, Ph.D. Dissertation Sharif University of Technology ; Abbaspour Tehrani Fard, Majid (Supervisor)
Abstract
The demand in water and energy for household, industrial and agricultural uses continue to grow. In recent years, many researches have been done on thermodynamic assessment and optimization of Combined Cooling, Heating and Power (CCHP) and desalination systems. The interesting and important point is the potential of combining CCHP and desalination systems by employing the solar power. The purpose of this study is exergy analysis and thermoeconomic optimization of a hybrid system of Multi-Effects Distillation desalination (MED) and CCHP, augmented by solar energy. The thermoeconomic analysis is carried out by Total Revenue Requirement (TRR) method. Properties of working fluid in hybrid MED...
Saline brine desalination: Application of sweeping gas membrane distillation (SGMD)
, Article Desalination and Water Treatment ; Volume 71 , 2017 , Pages 12-18 ; 19443994 (ISSN) ; Kargari, A ; Bastani, D ; Soleimani, M ; Shirazi, M. M. A ; Sharif University of Technology
Desalination Publications
2017
Abstract
In this work, desalination of saline brines using the sweeping gas membrane distillation (SGMD) process is investigated. The Taguchi method was applied for optimization of the operating parameters. An L9 orthogonal array was used to investigate the influence of pertinent variables, including feed temperature (Tf: 45°C, 55°C and 65°C), feed flow rate (Qf: 200, 400 and 600 mL/min), feed concentration (Cf: 10, 25 and 50 g/L) and sweeping gas flow rate (Qc: 4, 10, and 16 SCFH) on the distillate flux. Results of the experiments showed that maximum distillate flux, which was about 10 L/m2 h, obtained at 65°C feed temperature, 16 SCFH sweeping gas flow rate and brackish water with 10 g/L salt...
Enhancing forward osmosis (FO) performance of polyethersulfone/polyamide (PES/PA) thin-film composite membrane via the incorporation of GQDs@UiO-66-NH2 particles
, Article Journal of Water Process Engineering ; Volume 33 , 2020 ; Bayrami, A ; Amini, M ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
In this study, first, the UiO-66-NH2 metal-organic frameworks (MOFs) were modified with graphene quantum dots (GQDs) to facilitate the water attraction on MOF surface as well as improve their compatibility/affinity with the polyamide layer matrix of forward osmosis (FO) membranes. Next, to fabricate a new type of thin-film nanocomposite (TFN) membranes, the synthesized GQDs@UiO-66-NH2 composites are incorporated into the polyamide (PA) selective layer of FO membranes during the interfacial polymerization reaction of m-phenylenediamine (MPD) and trimesoyl chloride (TMC). The influence of the prepared fillers on the chemical structure, morphology, surface roughness and hydrophilicity of the PA...
Experimental study of forced circulation evaporator in zero discharge desalination process
, Article Desalination ; Volume 285 , January , 2012 , Pages 352-358 ; 00119164 (ISSN) ; Mowla, D ; Jafari Nasr, M. R ; Soltanieh, M ; Sharif University of Technology
Abstract
Zero discharge desalination process is the most promising technology to prevent salinity and thermal shocks to ecosystem by effluent streams of desalination unit drained into the sea. Pretreatment, solar pond and forced circulation crystallizer are the major steps of one option to provide the purposes of zero discharge desalination process. Reduction of total hardness of wastewater occurs in pretreatment unit and the solar pond is proposed for effluent concentrated brine wastewater of pretreatment unit which seeks production of potable water and concentrated brine. The effluent stream from solar pond is conveyed to one forced circulation evaporator in order to produce salt and distilled...
An investigation on using MDCs for an efficient desalination process as pretreatment of reverse osmosis
, Article Journal of Water Supply: Research and Technology - AQUA ; Volume 69, Issue 4 , 1 June , 2020 , Pages 322-331 ; Abbaspour, M ; Javid, A. H ; Hassani, A. H ; Sharif University of Technology
IWA Publishing
2020
Abstract
Microbial desalination cell (MDC) is a new bio-electrochemical technique which converts chemical energy into electrical energy, and at the same time desalinates water and treats wastewater. In this study, MDC performance and water biofouling conditions were tested as an efficient pretreatment desalination process of reverse osmosis (RO). The experiments were designed in a three-chamber reactor to compare the performance of batch and continuous fed modes, using bio-cathode and synthetic wastewater in four different hydraulic retention times and 17 and 35 g/L NaCl concentrations. According to the results, maximum salt removal of about 52.3% was obtained in the continuously fed MDC at 35 g/L...
Enhancing water desalination in graphene-based membranes via an oscillating electric field
, Article Desalination ; Volume 495 , December , 2020 ; Moosavi, A ; Nouri Borujerdi, A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Water desalination methods on the basis of newly developed graphene-based membrane have been introduced as a more efficient alternative for the conventional water purification technologies such as classical thermal desalination and reverse osmosis (RO). However, the increase of water permeation rate and ion rejection are still the main subjects in this field. In this study, a new method based on using oscillating electric field is proposed to improve the performance of nanoporous graphene. The effects of the amplitude and oscillation frequency of the electric field and the pore size of the membrane on the water permeation and salt rejection are studied by conducting molecular dynamics...
Development of artificial neural networks for performance prediction of a heat pump assisted humidification-dehumidification desalination system
, Article Desalination ; Volume 508 , 2021 ; 00119164 (ISSN) ; Behnam, P ; Shafii, M. B ; Khiadani, M ; Sharif University of Technology
Elsevier B.V
2021
Abstract
In this study, the application of data-driven methods for performance prediction of a heat pump assisted humidification-dehumidification (HDH-HP) desalination system was investigated for the first time. Although HDH-HP desalination systems have been widely studied both theoretically and experimentally, the application of data-driven models as a powerful predictive tool has not yet been investigated in these systems. To fill this gap, three data-driven models (MLPANN, RBFANN, and ANFIS) were applied using 180 experimental samples. The gain output ratio (GOR), heat transfer rates of the evaporator Q̇e, and evaporative condenser Q̇c, were considered as outputs. The results indicate that the...
Exergy and Thermoeconomic Analysis of Hybrid Desalination Unit (RO+MED) Coupled with a Combined Cycle Power Plant (Case study: Mapna standard design for Combined Cycle Power Plants)
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Hassan (Supervisor) ; Abbaspor, Majid (Co-Supervisor)
Abstract
In recent years, providing sustainable water supplies in dry and low water areas in the south of country is one of the important problems in the country. In addition to advantages of using cogeneration systems (power plant and desalination unit), using hybrid technologies causes productivity and reduction in energy consumption and water supplies. The target of this thesis is studying different thermal coupling scenarios to find optimum and constraint design in specific conditions in terms of cost and production. So in this conceptual study, by using thermoflow software, the hybrid unit coupled with a back pressure and condensing combined cycle power plant was studied based on thermodynamic...
Thermal Pollution Modeling of Power Plants Effluent Discharge and Impact on the Sea Bed Environment
, M.Sc. Thesis Sharif University of Technology ; Abbaspour Tehrani, Madjid (Supervisor) ; Mehdigholi, Hamid (Supervisor)
Abstract
The sea's ecosystem is the most sensitive and essential as the last recipient of sea and land pollution. The increasing requirement for building thermal power plants and desalination plants and a great demand for their thermal effluents discharge causes a serious threat to the rich coastal environment. In this project, a general study on environmental and meteorological data required to investigate the environmental effects of effluent discharge from desalination plants in the Persian Gulf and the Sea of Oman has been conducted, and the general process of conducting thermal effluent discharge research in this area is presented. Next, in a case study using MIKE hydrodynamic software and...
Optimal Design of Seawater Greenhouse Using Solar and Waste Heat Energy
, M.Sc. Thesis Sharif University of Technology ; Roshandel, Ramin (Supervisor)
Abstract
Agriculture is one the most water consuming sections in the world and roughly 60% of water demand is dedicated for this purpose. A seawater greenhouse manages to combine fan and pad greenhouse with humidification-dehumidification desalination in order to achieve water production next to agriculture products using moister in air which was used for cooling. The most important aspect of a seawater greenhouse is the amount of produced water. Many research on the condenser type and materials have been conducted in order to achieve a better performance, suggesting the utilization of a low temperature water source for the condenser. In this research, using a thermodynamic correlations to model the...
Molecular Dynamics Simulation of Water Nanofiltration by Graphene Oxide Membranes
, M.Sc. Thesis Sharif University of Technology ; Tavakoli, Rohollah (Supervisor)
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...
Design, Manufacture and Study of a Desalination System with Heat Pipe and PTC
, M.Sc. Thesis Sharif University of Technology ; Behshad Shafii, Mohammad (Supervisor)
Abstract
According to studies on solar stills, there has been designed an industrial solar still with a linear parabolic through collector (PTC) having higher efficiency than similar systems. Linear PTC coupled with heat pipe is very effective for increasing the efficiency of solar still. This system includes a parabolic trough collector functions by focusing the sunlight on a heat pipe and absorption of heat by a heat pipe. To minimize heat loss, heat pipe is embedded in an evacuated tube collector. By absorbing the heat, the working fluid of the heat pipe (ethanol) will be evaporated and due to its reduced density, it moves upwards and attains to the condenser. The external part of the condenser is...
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...
Adsorption Processes in Capacitive Deionization
, M.Sc. Thesis Sharif University of Technology ; Taghavinia, Nima (Supervisor)
Abstract
Today the water crisis affects billions around the world.According to existance of large amount of salty water on the earth, it seems one of the best soloution is desalination of salty water.There are methods for removing ions from water such as thermal methods, membrane methods , chemical methods and capacitive deionization.Capacitive deionization is based on the deviation of ions in the electric field.CDI system contains of two conductive porous electrodes that an elecric field is applied between them.While the brine pass through the space between the elecrodes the ions are absorbed by elecrodes. After a while the electrodes get saturated so a reverse potential is needed to regenerate the...
Charge asymmetry effect in ion transport through angstrom-scale channels
, Article Journal of Physical Chemistry C ; Volume 123, Issue 2 , 2019 , Pages 1462-1469 ; 19327447 (ISSN) ; Fan, J ; Esfandiar, A ; Zhu, Y ; Wu, H ; Wang, F ; Sharif University of Technology
American Chemical Society
2019
Abstract
Structural and dynamic properties of ions confined in nanoslits are crucial to understand the fundamental mechanism underlying a wide range of chemical and biological phenomena. K + and Cl - show similar ion mobilities in a bulk aqueous solution, whereas they exhibit a remarkable difference when transporting through an angstrom-scale channel. Our molecular dynamics simulations uncover that such discrepancy originates from the subtle differences in their hydration structures and preferable locations across the channel. Opposite charge causes different water dipolar orientations around ions, mediating the distance and tribological interactions between hydrated ions and channel's walls....
Magnetic carbon nanocomposite derived from waste tire rubber for atrazine removal from aqueous solutions
, Article Desalination and Water Treatment ; Volume 252 , 2022 , Pages 219-232 ; 19443994 (ISSN) ; Borghei, M ; Takdastan, A ; Javid, A. H ; Zazouli, M. A ; Sharif University of Technology
Desalination Publications
2022
Abstract
In this study magnetite nanoparticles (Fe3 O4) were synthesized and embedded in activated carbon (AC) derived from waste tire rubber to produce magnetic activated carbon. The atrazine (C8 H14 ClN5) adsorption was performed over (AC/Fe3 O4) nanocomposite in an aqueous solution and adsorp-tion isotherms and kinetics were determined. The effects of some parameters such as (pH, contact time, adsorbent dosage and initial pesticide concentration) were investigated. Characterization of nanocomposite was carried out by high-resolution scanning electron microscopy and transmission electron microscopy, X-ray powder diffraction, vibrating sample magnetometer, Brunauer–Emmett– Teller, Fourier-transform...
Techno-Economic Comparison between Reverse Osmosis and Multi-Effect Distillation for Desalination in Iran
, M.Sc. Thesis Sharif University of Technology ; Bastani, Dariush (Supervisor) ; Feylizadeh, Mehrzad (Supervisor)
Abstract
The current work studies the economic investigation of reverse osmosis (RO) desalination unit and multi-effect distillation (MED) considering the average global and also Iran circumstances. Technical and operational parameters are taken into account for economic modeling of both methods to choose the proper and economic method for water desalination based on different operational conditions. The cost of the desalination plants is investigated in two different parts of capital cost and operating and maintenance cost. Capital cost is divided into direct and indirect cost subsections. Based on these calcifications, the effect of economic parameters on change of capital cost and operating and...
Manufacture and Experimental Study of the Desalination System and Atmospheric Water Generator with Evacuated Tube Collector
, M.Sc. Thesis Sharif University of Technology ; Shafii, Mohammad Behshad (Supervisor)
Abstract
This research aims to design and build a device that Using solar energy and can be used as water heaters and water desalination and water from the soluble hygroscopic. For this purpose, a combination of evacuated tube collector with parabolic through collector with sun tracking mechanism is used. sun tracking mechanism is polar and works with optical sensor. in this research we have designed new setup with evacuated tube collector for direct desalination and water heater. in this method heat pipes have been omitted from setup that cause high performance in heat transfer from evacuated tube collector to water and is minimized losses. 15w air compressor used to increased rate of evaporation ...
Modeling of Brine Water Discharge into the Sea from Desalination Plants and Its Impacts on Sea Environment
, M.Sc. Thesis Sharif University of Technology ; Abbaspour Tehrani, Madjid (Supervisor) ; Mehdigholi, Hamid (Supervisor)
Abstract
Recent studies have shown that almost 40% of the world's population faces a water crisis, and this amount will reach about 60% by 2025. Due to limited freshwater resources and the increasing world population, we have to use seawater desalination systems to supply water to this growing population. One of the outputs of desalination plants in addition to freshwater is saline effluent or brine water, which is the most important environmental impact of these plants. In this study, an attempt has been made to investigate the various factors affecting the discharge and release of saline effluent from desalination plants and observe its impact on the ecosystem and marine environment. In this...