Sharif Digital Repository

Intelligent control or management of well or reservoir is a method which is used in order to optimize the production for increasing recovery factor so that the minimum damage or reduction of pressure occurs during production lifetime. Azar oilfield has 17 wells and the production from this field isn't started. Thereupon designing a suitable well completion model and a control algorithm to optimize the production for the first two years of production is necessary and indispensable. For this purpose, by collecting basic information and their analysis (for example pressure, temperature, production rate, the type and amount of produced fluids), designing of downhole installations and modeling... 

Water base drilling fluids are the most common drilling fluids in oil and gas operations and biopolymers are the requisite additives used in such kind of fluids frequently. Unfortunately, at harsh conditions of HPHT the polymers undergo thermal degradation which cause serious loss in fluid rheological and filtration properties. Accordingly, this will induce operational pitfalls and tremendous cost. The power of economy along with environmental regulations force us to search for reasonable chemically benign additives to fulfill this need. Nanoparticles are the most promising additives proposed in this study to address this challenge. Regarding their unique exclusive properties, they are able... 

The increasing demand for energy forced to production of oil as one of the main sources of energy. Along with the increase in oil production, the proportion of water produced with oil is increasing relative to the oil produced. On the other hand, environmental restrictions for the discharge of industrial effluents into the environment are becoming more and more stringent every day. Before discharging the effluent into the environment, petroleum must be removed. The complexity of these issues demonstrates the need to develop new technologies and improve the efficiency of existing technologies. Gas flotation are among the technologies adopted in the field that have been used throughout the... 

In the recent years, there has been an increasing attention toward usage of ultrasonic for enhanced oil recovery practices. But, thorough knowledge of active mechanisms and spreading and characterization of developed fingers during this practice is not available. From the other hand, due to limited amount of light oil fields, more attentions towards recovery from heavy oils is the need of the hour. Documents show that the big issues during the enhanced oil recovery from heavy crudes are high density of reservoir oil as well as poor development of fingers during injection due to high mobility ratios. In this study, results of ultrasound effect on the heavy oil recovery and its effect on the... 

In this study two approaches were applied to predict the hydrate dissociation pressure of natural gas in the presence of aqueous water. One approach applied van der Waals and Platteeuw solid solution theory & PR EOS the other applied a feed forward multi layers artificial neural network (ANN) with 19 input variables (temperature, existence of hydrocarbon liquid and ice phase, gas phase composition, inhibitor composition in aqueous phase), and one hidden layer with 17 neurons. In comparison of both methods it was concluded that, in temperature above 12℃ , ANN is more accurate than thermodynamic model, but in lower temperature thermodynamic model is comparable with ANN. The trained network... 

In this project, theoretical and experimental study of methane adsorption on Multiwall Carbon Nano-Tubes (MWCNT) has been performed. This study has been conducted in the way to achieve a suitable method for methane storage and transportation. To carry out the experiments, the volumetric method was used up to 500 psia at various temperatures of 298.15 K, 303.15 K, 308.15 K. The effect of moisture was also studied at 298.15 K. Also, various adsorption isotherms were used to model the experimental data collected in this work. The results showed that the amount of methane adsorbed on the MWCNT can decrease with increasing the moisture and temperature of the adsorption cell. In order to... 

Asphaltene precipitation and deposition may cause severe problems during different stages of oil recovery. All proposed remediation techniques have proven costly and not highly effective, so prevention becomes the most beneficial way to counteract the problem. Revelation of the deposition mechanism and determination of the parameters are necessary in order to devise reliable prevention strategies.This work presents results of the effect of lean gas and CO2 injection process as well as natural depletion on dynamic asphaltene precipitation and deposition. In addition sets of experiments were performed in the same porous media using STO and solvent (with different volume ratios) to investigate... 

When the reservoir energy is too low for the well to flow, or the production rate desired is greater than the reservoir energy can deliver, it becomes necessary to put the well on some form of artificial lift to provide the energy to bring the fluid to the surface. Continuous flow gas lift is one of the most common artificial lift methods widely used in the oil industry. In continuous gas lift, gas at high-pressure is injected in a suitable depth into the tubing, to gasify the oil column, and thus facilitate the production. Every well has an optimal gas lift operating point at which it will produce the most fluid. Ideally, if there is no restriction in the total amount of gas available,... 

Long-term deactivation of a commercial K-promoted Fe2O3 catalyst used in the dehydrogenation of ethylbenzene to styrene monomer was studied using thirty months of operating data of three industrial SM radial fixed bed adiabatic reactors. The Langmuir-Hinshelwood, Hougen-Watson model (LHHW) was used for reaction kinetics modeling. The kinetics of coking from ethylbenzene and styrene and the short-term deactivation function due to the quick coke formation were also considered in the model. The kinetics of long-term deactivation of the catalyst for ethylbenzene dehydrogenation to styrene between 550 and 630 °C were determined by allowing the effects of temperature and time on the catalyst... 

In water drive or waterflooded reservoirs, a significant amount of oil is remained in the reservoir as the residual oil. A process known as gas assisted gravity drainage, in its tertiary mode, has been applied in a number of conventional reservoirs to recover this residual oil. Gravity drainage is the main mechanism of oil recovery in the gas assisted gravity drainage enhanced oil recovery process. Previous investigations has shown that gravity force, spreading coefficient, three phase capillary pressure and reservoir wettability have significant effect on oil recovered via this process. The feasibility of using such a process in a naturally fractured reservoir is investigated in this work... 

In this study equilibrium condition of pure hydrogen hydrates is determined with Lee-Holder model. Two hydrogen molecules and four hydrogen molecules encaged in the small and large cavities respectively. Langmuir constant of hydrogen is calculated with the Exp-6 potential. Lee et al. reported parameter of this model by integrating ab initio calculation with classical statistical thermodynamics. This model reasonably predicts dissociation pressures of hydrogen hydrates.Calculated reference parameters are used in modeling of binary hydrogen hydrates. Lattice distortion model is used for modeling of binary hydrogen hydrates with tetrahydrofuran (THF) as a promoter. Cavity radius and parameters... 

The behavior of biomolecules in mixtures is affected by the presence of electrolytes. For instance, in the presence of an electrolyte, solubility of most biomolecules like proteins,peptids and amino acids can be increased or decreased. As a biomolecule, urea is a protein denaturant and influences protein folding and protein-DNA binding. The presence of ions can affect the interactions between urea and water In this thesis, experimental data of density and electrical conductance of aqueous solutions of urea-NaCl were obtained at different physical conditions. Density measurement experiments were carried out at different temperatures from 20-40 oC. Apparent and infinite dilution molar volumes... 

Gas hydrate is a nonstoichiometric structure that has been produced from water and gas in appropriate thermal and pressure conditions. There has been a long time that scientists work on predicting hydrate production condition. Predicting the hydrate behavior for pure substances is easier than mixtures; because there are some behaviors of mixtures that we do not know their reasons yet. In this thesis, there has been tried to give a model to describe hydrate reactions to temperature and pressure changes besides predicting the hydrate type and the cage occupancy. Since the hydrate behavior is nonstoichiometric, it is useful to know the cage occupancy to predict the amount of hydrate... 

Gas hydrates are ice-like clathrate compounds. Methane and carbon dioxide can form gas hydrate and plug pipelines, in order to preventing of gas hydrate formation, inhibitors like salts and alcohols are added to the natural gas pipelines. In this work a molecular thermodynamic model based on statistical mechanics, is employed to predict the hydrate formation conditions for carbon dioxide and methane in the presence of aqueous ionic liquid solutions. The statistical model of Van der Waals and Platteeuw mixed with Holder model is employed for hydrate phase. An equation of state applicable to the systems containing electrolyte developed by coupling the statistical associating fluid theory... 

Synthesis gas to light olefin reactions especially propylene production is one of the important path for clean fuel production in gas conversion processes. The object of this study is to define true kinetic model of process first step (e.g. Synthesis gas to light Olefins). For that, kinetic model for Co/Mn/TiO2 catalyst, which has the best conversion and selectivity for propylene, has been developed. Kinetic reaction parameters were measured by kinetic modeling in (220-300)0C temperature , (1-5)bar pressure , H2/CO=(1:3) and (450-600)hr-1 space velocity .After studying with significant models ,the best fitting can obtained with "KPCO P 1/2H2/(1+aPco+bPH2 1/2)2"equation. Later to... 

Inrecent years,research onionic liquidsarehighly developed. Because ofthe uniqueproperties ofionic liquidssuch asnegligiblevapor pressureandthermalstability for use inlarge areasofmajor industries have been considered.However,ionic liquids because they have lessenvironmental wasteas an alternative to convention alorganic solventssuch asaminesalkanolanarise.Ionic liquid sassolventsfor theremoval ofacid gases such as water and gasare investigated. The solubility of CO2 and H2S in the [Emim] [OTF] (1-ethyl-3-methylimidazolium triflate) in the temperature range 303.15 to 343.15 K and pressures up to 2 MPa has been studied experimentally. In order to capture modeling, the model equations of state... 

Upscaling is an important step in hydrocarbon reservoir modeling which reduces the number of grid blocks of high detailed geological models to prepare them for flow simulation. This helps to speed up computational process, to keep the simulation (CPU) time within a reasonable range and to make future engineering analysis (history matching, comparison of production scenarios, Monte Carlo simulation and etc.) possible. The accuracy of post processing analysis heavily depends on the robustness and validation of the applied upscaling method. Although numerous methods have been proposed in the literature, overemphasizing the effect of scale on the behavior of complex governing equations has... 

This study investigates the dynamic adsorption of asphaltene-in-toluene solutions on pack of wet calcite. All experiments were performed on mineral packs in sand-pack with mesh sizes between 100 to 140 (105 to 150 micron) and porosities between 40 to 46 percent. A UV–vis spectrophotometer was used to monitor the outlet concentration of asphaltenes. Experiments were performed for seven ionic strength of sodium chloride (6 to 1500 mM), five ionic strength of sodium sulfate (6 to 2400 mM) and four ionic strength of these salts mixture (12 to 3300 mM). In previous experiments the asphaltene concentration is 500 mg/l. Also two experments were performed with asphaltene concentration of 2000... 

The increase in demand for liquid hydrocarbon fuels in recent years in the transportation sector as well as in industry has led to an increase in the concentration of pollutants in the atmosphere. Sulfur oxides are known as one of the most challenging pollutants in the world today. In recent years, with the increase in the amount of pollutants in the air and the problems caused by them, which endanger the health of the society, sensitivities have arisen regarding the entry of pollutants into the air. Therefore, the Environmental Protection Organization has set specific standards regarding the allowed amount of sulfur in liquid fuels. One of the new ways to reduce the amount of sulfur in...