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Gas Separation by TEG and Zeolite Na-Y Nano Particles Liquid Membrane
, M.Sc. Thesis Sharif University of Technology ; Bastani, Dariuosh (Supervisor) ; Kazemian, Hossein (Supervisor)
Abstract
In this research, in order to investigate the effect of zeolites nanoparticles on the separation performance of a liquid membrane, a TEG/Nano Na-Y was developed. To do this, a high yield nano zeolite Na-Y was synthesized using mid-synthesis addition method . The synthesized samples were characterized by XRD, FT-IR, and SEM (EDX) instrumental techniques. A supported liquid membrane was prepared by impregnating a porous hydrophilic PVDF support with TEG and nano zeolite Na-Y. Permeances of single gas components of CO2, N2 and O2 were carried out at different pressures of 0.8, 1.8 and 3.7 bar. The single gases permeances were found to be: CO2 > N2 > O2. The results were shown that higher weight...
Preparation and Surface Modification of PC Membranes for Gas Separation
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor) ; Goodarznia, Iraj (Supervisor)
Abstract
The gas separation properties of polycarbonate (PC) membranes were investigated in this study. These membranes were prepared via dry and dry-wet phase inversion technique. Pure O2, N2, and CO2 gases were permeated through prepared membranes. The effects of membrane preparation conditions, including solvent type, non-solvent type, non-solvent/solvent volumetric ratio, polymer weight fraction, and drying temperature on the gas separation properties of dry PC membranes were investigated using Taguchi experimental design. Taguchi analysis show that polymer weight fraction offers the most important effect on the separation characteristics of the dry PC membranes. To get the highest...
Preparation of TEG Supported Liquid Membrane with Nano Particles of LTA Type Zeolite and Investigation of The Membrane Performance in Gas Separation
, M.Sc. Thesis Sharif University of Technology ; Bastani, Daryush (Supervisor) ; Kazemian, Hossein (Supervisor)
Abstract
The purpose of this research project was to improve the performance of TEG liquid membrane in separation of gas mixtures by adding zeolite LTA nanoparticles. Therefore, the NaA zeolite particles with nano size were synthesized with hydrothermal method at optimized condition. The supported liquid membrane with hydrophilic PVDF membrane and triethylene Glycol (TEG) was prepared in two different conditions. In the first one, the pores of the supporting membrane were filled with triethylene Glycol, whereas in the second one the pores were filled with the mixture of triethylene Glycol along with the 5 wt% and 10 wt% zeolite nanoparticles. The performances of prepared membranes were investigated...
Flare Gas Recovery and Transforming Them into Petrochemicals
, M.Sc. Thesis Sharif University of Technology ; Sattari, Sourena (Supervisor)
Abstract
By combustion, waste toxic, flammable and corrosive materials are changed to less inviromental problems by combustion. It also creats environmental problems (the most serios problem is caused by burning gases), as well as economic resources are wasted. So several ways was investigated to reduce combustion gases. Mini-methanol plant is one of varios possible ways that can convert these gases in to methanol. So methanol plant was simulated and then pinch analysis was performed on the simulated plant. Performing of pinch analysis caused 94.5 percent and 25 percent reduction in amaunt of hot and cold utility respectively. Before and after pinch analysis, the exergy analysis was performed on...
Surface Modification of Polyethersulfone Membrane by Plasma Treatment for Gas Separation
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor)
Abstract
In this study, the effects of treatment time and power of Low-frequency (LF) O2 plasma has been investigated for the surface treatment of polyethersulfone (PES) gas separation membranes. PES membranes prepared using dry/wet phase inversion using ternary mixtures containing 1-methyl-2-pyrrolidone (NMP) as solvent, water as non-solvent. The optimum polymer concentration was 32 wt.% , 61 wt.% and 7 wt.% for PES,1-methyl-2-pyrrolidone and water respectively. Pure CO2 and CH4 gas permeation measurements were performed before and after plasma treatment. After treatment gas permeances of around 0.81 GPU for CO2, and 0.073 GPU for CH4 with selectivities of around 11.23 for CO2/CH4 were obtained....
Technical and Economical Feasibility Study of Using Flare Gas for Converting to Other Products in Iran
, M.Sc. Thesis Sharif University of Technology ; Sattari, Sourena (Supervisor)
Abstract
The Increasing trend of gas flaring over oil fields and gas process systems in Iran not only causes several environmental problems, but makes the economical resources useless as well. Considering the high amount of flaring and old facilities, one of the best solutions is the recovery of the flare gas in Iran. It seems that collecting the flare gas is not possible in different sectors. Therefore, using a plant for converting flare gas to other products must be logical. In this project, the feasibility study of converting flare gas to other products is studied. For this reason, a methanol plant is simulated; whose input feed is the content of flare gas of the South of Iran (Marun and Siri)....
Experimental Investigation of the Effect of Nano-Fluid on the Performance of Pulsating Heat Pipe
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Hassan (Supervisor) ; Kazemzadeh Hannani, Siamak (Supervisor) ; Shafii, Behshad (Supervisor)
Abstract
Improving efficiency of heat exchangers has always been an important concern for the industry. Pulsating Heat Pipes (PHPs) are novel and efficient technology in the field of heat transfer. PHPs are widely used in solar water heaters, solar desalination systems, etc. In this research, thermal performance of Open Loop Pulsating Heat Pipes (OLPHPs) using three different ferrofluids (ferrofluid without surfactant and nanoparticles’ coating, ferrofluid with coating of nanoparticles, and ferrofluid with surfactant) is experimentally investigated. In addition, effects of charging ratio (20, 40, 60, and 80%), heating power (20, 30, 40, 50, 60, 70, 80, 100, 120, 140, 160, 180, 200, 240, 280, 320,...
Separation of Carbondioxide from CO2-Air Mixture Using ILM Membrane Containg DGA-TEG
, M.Sc. Thesis Sharif University of Technology ; Bastani, Dariush (Supervisor)
Abstract
In this research, initially the Triethylene glycol and Diglycol amine liquid membrane which is supported by PVDF, was prepared in order to separate the Carbone dioxide from CO2-Air mixture. A polyvinylidene fluoride (PVDF) membrane was chosen to have chemical resistance to solution. The effect of Pressure, Concentration of TEG and DGA solution and the percentage of carbon dioxide in feed; in rate and permeability of CO2, N2 and O2 and also selectivity of CO2/ N2 , CO2/ O2 and N2/ O2 was investigated. Transport of CO2 was facilitated due to reversible chemical reaction between CO2 and amine solution. The experiments were done in 0.4, 0.6 and 0.8bar and different concentration of solution....
Separation of Oxygen from Gas Mixture of Carbon Dioxide and Oxygen with Cyclohexanol and Triethylene Glycol Liquid Membrane in the Presence of Metal Oxide Nanoparticles
, M.Sc. Thesis Sharif University of Technology ; Bastani, Daruoosh (Supervisor)
Abstract
In this research, the effect of feed flow concentration on the separation of gas mixture of carbon dioxide and oxygen was investigated by using supported liquid membrane in the presence of nano particles. In order to achieve this purpose, supported liquid membranes were prepared by impregnating a porous hydrophilic PVDF support with TEG, cyclohexanol, TEG/Fe3O4 nano particles and cyclohexanol/ Fe3O4 nano particles. Permeability and selectivity of mixed gases CO2 and O2 were examined at five different CO2 concentrations in feed flow, constant feed flow rate and constant total pressure difference.
In all tests, the permeance of carbon dioxide through cyclohexanol and TEG membranes was...
In all tests, the permeance of carbon dioxide through cyclohexanol and TEG membranes was...
Synthesis of Graphene Oxide and Graphene Oxide Membrane for Separation of Gas Mixtures
, M.Sc. Thesis Sharif University of Technology ; Ghotbi, Sirus (Supervisor) ; Karimi Sabet, Javad (Supervisor) ; Mousavi, Abbas (Co-Advisor)
Abstract
Thin film graphene oxide(GO) membranes have been promising potential for gas purification due to thin lamellar microstructure, stable a few atom thick layers and very short intersheet distances. In this research, the nanoporous graphene oxide membranes have been prepared by vacuum and pressurized ultrafiltration on the modified polyacrylonitryle(mPAN) sublayer for helium separation from Nitrogen and carbon dioxide gas mixture. The separation performance of synthesized GO membrane was controlled by varying parameters such as concentration of stabilized aqueous GO solution, pores size range of support and its surface properties, centrifuge time, applied pressure after synthesis, humidity,...
Spectral Solution of Inviscid Compressible Flow through Nozzles with Real Gas Effects
, M.Sc. Thesis Sharif University of Technology ; Hejranfar, Kazem (Supervisor)
Abstract
A collocation spectral scheme is used to compute inviscid supersonic high temperature flow in diverging nozzles. In order to include the real gas effects of high temperature air, chemical equilibrium is implemented via Tannehill et al. correlations. The proposed method is used for numerical simulation of internal inviscid flow of air in quasi one-dimensional and two-dimensional forms. Chebyshev spectral method is applied to the governing equations in order to discritize spatial differentiation terms and an explicit four stage Runge-Kutta method is chosen for time integration. The equations in primitive formulation are modified to include real gas effects. The effects of equilibrium or...
Smulation of Hydrogen Production by the Process of Thermal Decomposition of Methane
, M.Sc. Thesis Sharif University of Technology ; Saboohi, Yadollah (Supervisor)
Abstract
Different disadvantages associated with using fossil fuels as the main energy source including crisis of wells’ depletion and serious environmental problems, causing by the emission of large quantities of greenhouse gases (GHG), especially carbon dioxide (CO2), has increased attention to replacing them with renewable and clean fuels such as wind, solar, and geothermal energy sources. Hydrogen, as a clean energy carrier, is one of the best fuels in terms of the environment and cost. So, it is recently receiving increasing attention and it may one day replace fossil fuels for various applications such as in automobiles and power stations. The main subject of this thesis was surveying the...
(Assessing the Role of Carbon Capture and Storage Technology on Iran’s Oncoming Energy System(Technology Deployment Policy Making
, M.Sc. Thesis Sharif University of Technology ; Maleki, Abbas (Supervisor)
Abstract
Based on International Energy Agency studies, achievement of 450 ppm CO2-equivalent emission target in global emission means that the CO2 emissions in 2050 must be reduced to %50 of 2005 level, and this implies that a portfolio of emission reduction policies and strategies need to be exploited through current century.
At the present time, Carbon Capture and Storage (CCS) Technology is a dominant strategy among all the long-term carbon abatement strategies in many countries. Nevertheless, its potential as a climate mitigating option will be proved, only if it is implemented in the countries which are developing at a great pace and taking advantage of fossil fuels in order to afford their...
At the present time, Carbon Capture and Storage (CCS) Technology is a dominant strategy among all the long-term carbon abatement strategies in many countries. Nevertheless, its potential as a climate mitigating option will be proved, only if it is implemented in the countries which are developing at a great pace and taking advantage of fossil fuels in order to afford their...
Multi-criteria Model Development to Evaluation of Waste Energy and Material Recovery in Tehran
, M.Sc. Thesis Sharif University of Technology ; Saboohi, Yadollah (Supervisor)
Abstract
Waste management is one of the essential and basic utility services in 21st century, especially in rural areas. It includes different environmental, technical, economic, legal and social aspects which need to be considered in levels of waste generation, transport, treatment and disposal. Therefore, considering economic criterion in waste management programs, as the only one criterion, will result in environmental impacts in long-term and impose high costs to the society and the economy overall. The main purpose of this study is to develop a multi-criteria mathematical model, which take into account both economic and environmental criteria in order to present an integrated municipal solid...
A Mathematical Model to Prediction of the Formation of Microporsities in Aluminium Alloy Cast Parts
, M.Sc. Thesis Sharif University of Technology ; Varahram, Naser (Supervisor) ; Davami, Parviz (Supervisor)
Abstract
Today, application of aluminium alloys in industries is developing. And this is because of some specification of these alloys like high proportion of the Strength per weight. One of the most useful alloys of this alloy group is A356 alloy that contain 7 % Silicon and 0.4 Percent of magnesium, this alloy because of cast ability, heat treat ability specification is use developing in air and automotive industries. But usage of this alloys combined with some difficulties like low fluidity and formation of shrinkage and gas porosities in this alloys. In present work with programmer software Visual Fortran, based on Finite difference method, a simulation model has been developed, can solve heat...
Design and Analyzing a Flameless Combustion Furnace for an Applicable Industrial Setup
, M.Sc. Thesis Sharif University of Technology ; Mazaheri, Karim (Supervisor)
Abstract
Flameless combustion is among the newest combustion technologies that is used for reducing the pollutants in recent couple of decades. Within this combustion regime, diminution of super hot points throughout the combustion chamber along with decline in production of pollutant gases occur simultaneously. This kind of combustion often is created by applying two processes; first by preheating the fuel and/or oxydizer flows at the inlet to tempratures over the self-ignition level; and second with diluting the whole amount of fuel and oxidizer in the chamber. These two happen by using hot exhaust gas of the same chamber (via feedback) or of the previous section (in multi-section chambers)....
Modifications in Commercial Diesel Engines to Perform Under Difficult Respiration Conditions
, M.Sc. Thesis Sharif University of Technology ; Durali, Mohammad (Supervisor)
Abstract
In this project we are about to adopt a method for implementing commercial diesel engines (truck and bus engines) in applications with difficult respiration condition like what happens in a submarine. To this end, working conditions of such engines are introduced and standard constraints are explained. Then the structure of already manufactured submarine engines is presented. At this point an engine from known manufacturers was selected for calculations to be performed on it. Since test and measurement equipments were not yet ready, simulation using computer software (GT-POWER v6.1) was selected as the solving method. First, the engine was modeled in its nominal working conditions. After...
Oxygen Enrichment of Air by Membrane Technology to Reduce Energy Consumption
, M.Sc. Thesis Sharif University of Technology ; Bastani, Dariush (Supervisor)
Abstract
In various industries, for energy production, fossil fuels are burned. Oxygen needed for combustion, taken directly from the ambient air; So that the inert gas is about 80%. The presence of this inert gas, mainly nitrogen, reduce combustion efficiency and increase the use of combustible material. In this project with the help of membrane technology, was used to remove the amount of nitrogen in the air so that the incoming air into the combustion chamber is enriched with oxygen. For this purpose, several gas separation membrane was applied and evaluated. Then, according to the oxygen enrichment, fuel efficiency and the amount of savings, increasing chamber temperature, reduction manufacturing...
Green Supply Chain Management by Minimizing Carbon Footprint, Case Study KALLEH Meat Products Company
, M.Sc. Thesis Sharif University of Technology ; Abrishamchi, Ahmad (Supervisor)
Abstract
When increased emissions are combined with a carbon tax or emissions trading system, the result is a supply chain with increased costs attributable to the emission generated on the different parts of supply chain. Most traditional supply chain design models do not take emissions and carbon costs into account. Hence, there is a need to incorporate emission costs into a supply chain optimization model to see how the optimal supply chain configuration may be affected by the additional expenses. This thesis presents a mathematical programming model for the design of green supply chains. The costs of carbon dioxide equivalent emissions were incorporated in the objective function, along with the...
Thermal Modeling and Simulation of a Lithium-ion Battery
, M.Sc. Thesis Sharif University of Technology ; Pishvaie, Mahmoud Reza (Supervisor)
Abstract
Today, considering the global demand for reducing greenhouse gas emissions, rechargeable batteries are considered as a source of energy in electric vehicles, hybrid electric vehicles and smart grids. In all these applications for secondary batteries, the battery management system requires an accurate estimate state of charge of each cell. However, this estimate is difficult particularly for battery aging. In this study, a lithium-ion battery is modeled by using multidimensional multiphysics modeling and simulated in a comsol. In this simulation, the effect of the thermal conductivity coefficient on the battery temperature, initial salt concentration in electrolyte and the rate of discharge...