Sharif Digital Repository

With considering the existence of carbonyl sulfide in natural gas and crude oil, we need to study the absorption of this gas in aqueous alkanolamine solutions. In this project the solubility of carbonyl sulfide in different pressures and two temperatures of 313.15 and 348.06 K have been measured.The absoption of carbonyl sulfide in aqueous alkanolamine solutions is a very slow process. In this study we used different methods for measuring the required data. Befor the experiments we calibrated the set up with reliable data. Finaly the results simulated with Deshmakh-Mather thermodynamic model, numerically. The simulation results show a good agreement with experimental data  

Many technologies should be applied for transportation or consumption of natural gas. There are many different ways for transporting natural gas from origin of production to the location of consumption which the simplest way is transportation via pipelines but for transportation of natural gas for long distances, we can not use this method in this way we should apply other technologies such as converting the natural gas to the liquid state. For using this method, first we should liquefy the natural gas up to -162 degree of centigrade at the atmospheric pressure and then transport it with large cargo ships. By using this method, the transportation costs are decreased in compared with the... 

Formation of gas hydrates is a challenge in the oil and gas industry. Gas hydrate formation can be prevented by several methods. One of these methods is to utilize of inhibitor components. The gas hydrate inhibitors can affect hydrate formation from two aspects, i.e., thermodynamic or kinetic. In this work, thermodynamic and kinetic effects of [Emim][BF4] ionic liquid on growth and dissociation of methane hydrate crystal were investigated using molecular dynamics simulation. Molecular dynamics simulation is powerful tool to investigate the thermophysical, structural, and dynamic properties of methane hydrate and the formation, dissociation, and inhibition mechanisms at the molecular scale.... 

In this work the effect of composition changes of the injection gas (Hydrocarbon gas + carbon dioxide) on Water Alternating Gas (WAG) performance in immiscible flooding which has been rarely attended in the available literature is investigated. Core flood experiments are conducted on a 10 cm length Sarvak sandstone core sample at 46 degree C and at immiscible condition, i.e., below the minimum miscible pressure (MMP) of the oil sample using pure CO2 as injected Gas.The influence of injection WAG ratio on oil recovery also is investigated. Artificial injection brine which is made by dissolving NaCl into distilled water with 5000 ppm (mg/L), NaftShahr oil which has about 41 API gravity and... 

In past three decades, use of crude oil’s derivatives increased dramatically. The critical environmental condition of today’s world, which majorly caused by unclean fuels, forces governments to legislate new rules to increase quality of fuels. These rules force refinery industries to produce clean fuels. One of the main processes in producing clean fuels is Desulfurization process. For fuel desulfurization there are different kinds of processes like HydroDesulfruization, Oxidative Desulfurization, Bio-desulfurization, etc. From these processes Hydro-desulfurization is the conventional process for desulfurization. Because of significant problems of this process, like high operational cost,... 

Unconventional fracturing applications such as long-term waterflooding at fracturing pressure, produced water re-injection and waterfracs, etc., are characterized by very high fluid leakoff velocity, long operation time and significant changes in stress, pore pressure, and/or permeability and porosity, affecting possibly large regions around the wellbore and/or fracture. These special characteristics make fracturing modeling methods developed for conventional fracturing applications inadequate. Some of the problems encountered include grid effects resulting in oscillation of fracture growth with time (limiting the stability of conventional fracture modeling models), singularity of material... 

In this study, density, viscosity and surface tension of aqueous solution of Sulfolane, ( TEA+TMS+H2O) and (DIPA+TMS+H2O) systems were measured . Density, viscosity and surface tension were measured using pycnometer, Cannon – Fenske viscometer and Capillary rise method, respectively. Surface tension measurements of (DIPA+TMS+water) were carried out by the ring method using a LAUDR TD3 tensiometer,. The experiments were carried out in low concentrations and atmospheric pressure in the temperature range (70 - 30) . The obtained Data was modeled using empirical and thermodynamic models. Density calculation was done using the Setchenov and Redlich – Kister models.and the results indicated that... 

Removal of some hazardous and toxic components of natural gas is of a great importance in industries. Thus solubility measurement of these components in appropriate solvents is a necessary task. Methylmercaptan due to its high toxicity as one of these components is separated by means of Alkanolamines. In this project a physical solubility experimental setup for absorption Methylmercaptan (CH3SH) in 48wt%, 35wt% and 25wt% MDEA aqueous solutions at 50°C and in pressures between (0.7 to 3)bar was designed and developed. The suggested setup can be used for measurement of solubility of gases (physical and chemical) in different solutions. The performance basis of the system is on precise... 

In this study thermodynamics and kinetics effects of two ionic liquids (ILs) on the formation and dissociation of methane and carbon dioxide hydrates were investigated. The ILs used in this study are 1-butyle-3-metylimidazolium tetrafluoroborate, [Bmim][BF4], and 1-butyle-3-metylimidazolium methyl sulfate, [Bmim][MS]. At the first step of experimental section, the tetrahydrofuran (THF) was used in atmospheric pressure. The structure of THF hydrate is similar to natural gas hydrate; therefore it is used as a model for studying the properties and investigation of inhibitors effects on gas hydrates. In order to consider the effects of foregoing ILs on the formation and dissociation of gas... 

New experimental results are presented for the solubility of carbon dioxide and hydrogen sulfide sulfide in six imidazolium-based ionic liquids included 1-octyl-3-methylimidazolium tetrafluoroborat ([C8mim][BF4]), 1-octyl-3-methylimidazolium hexafluorophosphate ([C8mim][PF6]), 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)-imide ([C8mim][Tf2N]), 1-octyl-3-methylimidazolium trifluoromethanesulfonate ([C8mim][TfO]), 1-hexyl-3-methylimidazolium trifluoromethanesulfonate ([C6mim][TfO]), 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([C4mim][TfO]) at temperatures range from 303.15 to 353.15 K and pressures up to about 2.5 MPa. The solubilities of the mixture of CO2/H2S in... 

By continuous decreasing the fossil fuel energy resources and increasing demand of such energies on the other hand with decreasing exploration of the new ones, production from these limited resources are in grate consideration. As a few percentages of the oil recovers by primary oil production and also remaining a lot of oil after water and gas injection in the secondary oil recovery process, causes that new methods to increase the oil recovery has been proposed. Water injection is a simple and common method in enhanced oil recovery process. Also water alternating gas injection and simultaneous water and gas injection causes considerable increase in oil recovery. Recently utilization of... 

The acid fracturing process is a thermal, hydraulic, mechanical, geochemical and geomechanical coupled phenomena in which the behavior of these variables are interrelated. To model the flow behavior of an acid into a fracture, mass and momentum balance equations are used to draw 3D velocity and pressure profiles. Part of the fluid diffuses or leaks off into the fracture walls and dissolves part of the fracture face.An acid balance equation is used to draw the concentration profile of the acid and to account for the quantity of rock dissolved. An algorithm is developed for this process to generate the final conductivity distribution after fracture closure. The objective of modeling acid... 

In this study, a numerical investigation of propagation of sound through a fluid-saturated porous column has been proposed so that we can analyze the effects of porous media parameters on decreasing sound amplitude. The mathematical model applied for our simulation is based on Biot equations solved by an explicit finite difference method. Since Biot model is exclusively applicable to porous solids saturated with single fluid phase, in order to simulate a porous solid saturated with two immiscible fluids, we exploited the general Eulerian model instead of Biot model. Efficiency of porous sound absorbers is directly influenced by four major parameters which are porosity, rigidity and thickness... 

Crumb Rubber is one of the main polymer modifiers of binders. This modifier can improve chip seal performance against ravelling (aggregate loss). The most concerning distress in chip seal is ravelling. Aggregate loss is not restricted to the early life of chip seal, but continues throughout the service life. Chip seal can be made with hot binders or emulsion binders. These two type of binder were modified with 7% and 15% of crumb rubber in applicable way. Then, two major environmental effect on chip seal performance, freeze-thaw and asphalt aging, were investigeted based on laboratory test. For this purpose, authors used chip seal bonding test. Chip seal bonding test is developed recently... 

Viscosity is one of the most important properties used in simulating and optimizing transportation design and hydrocarbon reservoirs simulation. In this work, a new model based on the friction theory was used to correlate the viscosity for six different live and dead oil samples taken from the south of the Iranian oil region. As expounded by other researchers, in the friction theory, an equation of state is used to express the intermolecular viscous interactions. In model presented in this work, the standard cubic equations of state such as the SRK and PR were used to correlate the viscosity data for the samples under investigation. In the new model, the effect of critical viscosity on the... 

Landslides, like earthquakes, floods, and volcanoes, are important natural disasters that occur frequently in the mountainous and high regions of our country, especially in the Alborz and Zagros regions, which induce considerable damages. Various factors such as topography, lithology, weather conditions, hydrology, tectonics, earthquakes, and various human activities are effective factors in the instability of natural and man-made slopes. Not one factor can cause instability in slops, however, a combination of the named factors may cause landslides. Therefore, knowing the factors affecting the occurrence of landslides and identifying different areas in terms of sensitivity to their... 

Since the beginning of oil, gas and gas condensate production, the prediction of the formation of mineral scales in different operating conditions has been a serious challenge. Mineral scale are solid particles that are separated from the free water in the reservoir due to changes in the production conditions in terms of temperature and pressure or the fluid composition of the production fluid of reservoir, and there is a possibility of their deposing on the wall of the well column and in the production system, where The way of production from reservoirs faces serious risks. free water, which is permanently entering the pipeline, contains all kinds of salts in the structure of the fluid... 

In this thesis, combustion of liquid fuel spray under the condition of hot and diluted oxidizer, has been investigated. To this end, a novel type laboratory-scale test rig was designed to study the physics governing the MILD-Spray combustion conditions with an applied approach. The underlined test rig eliminates the operational problems of its predecessor test stands and is used for a heavier fuel with much more complex chemical composition (kerosene). The test section is axially symmetrical, in which the fuel is injected by a pressure-swirl atomizer in the direction of hot and diluted co-flowing air. With the use of the aforesaid test rig, the effect of variables such as oxygen...