Sharif Digital Repository

Considering the drastical increase of greenhouse gases in the atmosphere, especially carbon dioxide, reduction of these gases seems necessary to combat global warming. Fossil fuel power plants are one of the main sources of CO2 emission. In this paper, CO2 capture from a natural gas fired steam cycle power plant using oxy-fuel combustion technology is studied. The Integrated Environmental Control Model (IECM) developed by Carnegie Mellon University was used to evaluate the effect of this capture technology on the plant efficiency and economic parameters of the system. Since the oxygen production plant, CO2 capture and transport are cost and energy intensive, the cost of electricity generated... 

Globally energy system is the main source of green house gas emission. 60-90 percent of manmade CO2 is due to energy sector. Pollutants like NOx, CO, Non Methane Hydrocarbons which may cause indirect effect on climate system are mainly emitting from energy sector. Gas, Oil and Coal extraction and transmission are responsible for more than 15% of Methane emission globally. Therefore it is important to consider all types of GHGs emission as well as all sectors of energy system to assess the GHGs mitigation potential throughout the energy system. Considering the significance of energy sector in GHGs emission, in this study we developed an optimized model for Iran’s energy sector in which we ran... 

Due to the environmental concern for the harmful effect of the release of HFCs on global warming there has been more interest for the use of hydrocarbons as refrigerants in recent years. In this project the performance of these refrigerants have been studied and compared with common refrigerants from the quantitative and qualitative point of view using a real-scale model of Peugeot-405 air conditioning system. Charging amount, inside temperature, cooling load, energy consumption of cycle, coefficient of performance and required time to steady state condition are the important comparative criteria for such a study. After carrying out a series of tests it has been considered that charge... 

Nowadays, radical increase in energy consumption guides humankind to find and harvest some alternative energy resources. Between the energy resources that have ever been known, Solar Energy is the most traditional one and Solar Water Heaters (SWHs) are the most ancient tools that have been used to store this energy up to now. Regarding this issue, many researches have been done to investigate different aspects of SWHs and the most conventional type was Thermosyphon SWH system. In this study, our aim is to investigate the influence of Pulsating Heat Pipes (PHPs) application as a heat transfer tool to convey absorbed solar energy to hot water reservoir of a SWH. In order to do this research,... 

The purpose of this research is to model transport and separation of single and gas mixtures through pore network modeling in dense membranes. In the first part of the project, the mass transfer and governing mechanisms of transport are investigated. In the second part of the project, simulation of membrane pore network in 3D of Cartesian coordinate is done. In the third part of the project permeability of single gas and ideal selectivity of binary gases for an actual membrane by desired mechanism are calculated. Then the results of pore network modeling were compare with the results from molecular dynamic simulation for single gas in polyurethane membrane with reasonable agreement. In this... 

Partial oxidation of methane (POX) is one of the most common processes to produce synthesis gas. In this study the kinetics of this process is examined and some reduced mechanisms are introduced to model it in this study. The experimental data from Research Institute of Petroleum Industry are used as reference experimental data. Inlets of this reactor are oxygen and methane with equivalence ratio between 2.53 and 2.9. Moreover, the experimental results of previous studies with the air as the oxidant in equivalence ration between 2.4 and 2.6 are used as basis for comparison of simulation results. During the first step, partial oxidation of methane in non-catalytic porous media is simulated by... 

% of human blood makes up of plasma, that this plasma is a rich source of proteins that can be used as biomarkers for a variety of clinical diseases and laboratory research, therefore, it is necessary that the plasma be separate by a high purity percentage. Using a centrifuge It is a common method used to separate plasma from blood, but because it requires large equipment and a large volume of blood, as well as stress caused by centrifugal force, increases the probability of damage to the biomarkers, so it has been tried today that Use methods that are easy to transport and require a small amount of blood. The idea of using the microfluidic device has been put forward for the purpose of... 

Membrane Technology is rapidly growing all over the world because of many applications. In all of this applications , use of adhesive ( between membranes and wall ) is necessary. selection of appropriate adhesive for membrane is very important in order to membrane has best performance and lifetime .Adhesives used in membrane technology must have good adhesion and suitable hardness . One of the newest adhesives used in membrane technology is two-component polyurethane adhesive. PU adhesives make strong and durable bond and have good flexibility which is an advantage for membrane technology.MDI isocyanate is used in most of commercial PU adhesives’ formulation. But in this study , modified MDI... 

Electrolyte separator is the major component of lithium-ion batteries which the battery safety directly depends on it. In this work, a membrane separator based on the polyvinylidene fluoride (PVdF) was prepared via non-solvent induced phase separation (NIPS) method with water and ethanol as non-solvent and a mixture of dimethylformamide (DMF) and acetone as solvents. The effect of various acetone/DMF ratios and type of non-solvent on the structural, mechanical and electrochemical properties of separator was studied. The separator was characterized by FE-SEM, tensile strength, electrochemical AC-impedance spectroscopy, thermal stability and linear sweep voltammetry (LSV). Additionally, the... 

Oxygen enriched combustion is one of the attractive combustion technologies to control pollution and improve combustion in diesel engines. In the present work after an introduction to membrane seperation and membrane seperators for oxygen-nitrogen from air, a simulation of combustion chamber by GT-Power and membrane COMSOL Multiphysics was used to study the impact of oxygen enrichment on combustion, pollution and performance parameters with 23, 25 and 27% levels of enrichment. Increasing the oxygen engine content with the air leads to faster burn rates and the ability to burn more fuel at the same stoichiometry. These effects have the potential to decrease specific fuel consumption and... 

In this thesis, the application of solar energy in the steam injection as a thermal enhanced oil recovery (TEOR) is evaluated. The motivations of this project are using a renewable energy, suitable solar potential of Iran, successful experience in the world, undeveloped heavy oilfield reservoirs in Iran. This application is investigated by three aspects which are:Reservoir Engineering aspect: the heavy oilfield are determined and then screening for selection good candidate of steam injection are done. One of the reservoirs is analyzed by simulation and optimization the steam injection to determine how much it’s production will be improved by using steam injection (contionous and cyclic)... 

Flexible thermoelectric (TE) fabrics were prepared by dip coating of a mixture solution of water base colloidal geraphen nano sheet(GNS) and carbon nano tube(CNT) and polyaniline (PANI) on polyester fabric. The phase composition and morphology of the TE fabrics were investigated by FTIR-ATR diffraction and feld emission scanning electron microscopy. The TE properties of the PANI/GNS or CNT coated fabrics with different GNS and CNT loadings were measured in the temperature range from 303 to 338 K. As the content of GNS increased from 0.5 to 10 wt% and CNT increased from 0.5 to 20 wt%, the electrical conductivity of the PANI/GNS or CNT coated polyester fabrics increased, while the Seebeck... 

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... 

Textile dyes are a major category of organic pollutants and release of them in the environment causes serious problems. Among the most commonly used methods for colored wastewater, advanced oxidation processes, especially the photocatalytic process, are rapidly developing as a new and effective solution. However, there is still a need for high-level photocatalytic activity and improvement of this process to increase removal efficiency. In this study, we have tried to provide a higher performance for color removal using carbon nitride photocatalyst. Accordingly, two approaches have been proposed to improve the removal of rhodamine b, as one of the common dyes in the textile industries. The... 

Gas pollutants are included volatile inorganic compositions and odorous materials, which are harmful and dangerous for environment and human health. There are several methods for removing gas pollutants such as physical, chemical and biological methods. In this work, we discuss about ethyl-mercaptan adsorption in LPG by ZSM-5 zeolite and in use of micro systems (micro channels). This work is also concerned about micro channel coating by ZSM-5 and NaY zeolites on glass and the method of coating with (3-Chloropropyl) trimethoxysilane linker. After selecting the appropriate method for zeolite coating, we proceed to micro channel coating. In this research, four different designs of micro channel... 

In this study, we investigate the effect of adding potassium persulfate (PDS) (K2S2O8) and hydrogen peroxide (H2O2) to E.coli (as a model microorganism) photocatalytic removal system in the presence of the TiO2-P25 as photocatalyst and UV irradiation. In this regard, the PDS and H2O2 oxidants were added separately in the different levels of pH and photocatalyst loading under UV irradiation. The experimental points were determined based on the central composite design (CCD) and in order to study the main and the interactive effects of the photocatalyst concentration (mg/L), oxidant concentration (mg/L) and the pH on the final concentration of E.coli (cfu/mL), a response surface model (RSM)... 

Photocatalytic degradation is one of the developing modern and effective methods for decontamination of hazardous pollutants of chemical industrial wastewater. For this purpose, in this research, the efficiency of the photocatalytic process in degradation of Cortisone Acetate is investigated under solar light irradiation, and the effect of two useful oxidants, potassium persulfate (PDS) and potassium proxy mono sulfate (PMS), on the degradation efficiency is examined. At first, the single effect of these two oxidants, and then their interaction effects with the photocatalyst (TiO2-P25) and solution pH by analytical analysis and with the help of Response Surface Methodology (RSM) and... 

Due production and use of large amount of chemical and emissions of pollutants in air, detection and control of these compounds are necessary. One of the common methods to detect these pollutants in the ambient is using metal oxide semiconductor sensors. However, these types of sensors suffer from low selectivity toward a certain compound in the mixture of different gas components. In this study, the object was to investigate the effect of different amount of CNTs on performance of tin oxide to improve their selectivity for detection of 50 ppm of hydrogen sulfide at low temperature. To perform the study, nanoparticles of pure tin oxide and SnO2 base hybrids containing 0.25wt%, 0.5wt%, 2.5wt%... 

In this study nano zeolite was hydrothermally synthesized in order to remove ethyl and methyl mercaptans from propane and butane stream. Fifteen experimental runs were conducted using D-Optimal method experimental design to synthesize NaY, NaX and NaA zeolites. The products were characterized by measuring the morphology, particle and crystal size, surface area, adsorption isotherm, pore size, and pore volume of the products by XRD, FE-SEM, TEM and BET analyses. The pore size for NaA type zeolites is about 4 Angstrom whereas the molecular size for ethyl mercaptan and methyl mercaptan is between 4 and 5 Angtrom, Therefore, NaA zeolite is inappropriate for removing ethyl and methyl mercaptans... 

In this project dynamic effect of changes in gas turbine load on power plant, reforming and Co2 capture section is investigate. The reason for study of effects change of gas turbine load is that gas turbine determines the performance of the other parts in combined cycle including gas cycle and change of gas turbine load can alter the load and the performance of other parts in the power plant and in other process such as production of synthesis gas and carbon dioxide separation unit. One Autothermal reactor and eight sewgs reactor are utilized to produce gas turbine fuel which is mainly consist of Hydrogen. this part of thesis is to be implemented in the gPROMS from process system enterprise...