Sharif Digital Repository

A new nanocomposite polymer gel is synthesized for reduction of excess water production in petroleum reservoirs at real operating conditions. This new nanocomposite gel contains SiO2 nanoparticles, partially hydrolyzed polyacrylamide (HPAM) and chromium triacetate. High pressure and high temperature tests using porous carbonate core are carried out to evaluate the effects of nanoparticles on the synthesized polymer gel performance. It is shown that the residual resistance factor ratio of water to oil using the synthesized polymer gel nanocomposite in this work is much higher than that of the ordinary polymer gels. The presented results confirm the high performance of the synthesized... 

In this work, a new model based on the multilayer adsorption kinetic mechanism and four material balance equations for oil, asphaltene, gas, and water phase has been developed to account for asphaltene deposition in porous media under dynamic conditions and the model was verified using experimental data obtained in this work and also with those reported in the literature. The results showed that the developed model based on multilayer adsorption kinetic mechanism can correlate more accurately the oil flooding experimental data in comparison to the previous models based on the mechanical plugging mechanism, in particular in carbonate core samples. Also, a series of experiments was carried to... 

The objective of this study was to experimentally investigate the performance of water-alternating gas (WAG) injection in one of Iran's oil reservoirs that encountered a severe pressure drop in recent years. Because one of the most appropriate studies to evaluate the reservoir occurs generally on rock cores taken from the reservoir, core samples drilled out of the reservoir's rock matrix were used for alternating injection of water and gas. In the experiments, the fluid system consisted of reservoir dead oil, live oil, Co 2, and synthetic brine; the porous media were a number of carbonate cores chosen from the oilfield from which the oil samples had been taken. All coreflood experiments were... 

This experimental study is aimed at evaluation of the performance of secondary WAG injection in carbonate cores at different pressures. To do so, a comprehensive series of high-pressure high-temperature (HPHT) core flooding tests are conducted. The fluid system includes reservoir dead and live crude oil, CO 2, and synthetic brine while the chosen porous media consists of a number of fractured carbonate core samples. Parameters such as oil recovery factor, water and oil production rates, and pressure drop along the core are recorded for both dead and live oil. According to results, at first increasing pressure improves the oil recovery, but this improvement after MMP is not as significant as... 

This fact is well known that during any scenario of production, asphaltene deposition in porous media has a substantial effect on oil flow. But a clear understanding of asphaltene deposition mechanisms can help to minimize asphaltenic problem in oil-bearing formations. In this study, the experimental results of three dynamic CO 2 miscible injection tests were investigated. Regarding the effects of adsorption, mechanical entrapment, and sweeping mechanisms on permeability behavior, a mathematical mass and permeability variation model were developed. According to the experimental results asphaltene deposition causes a 70% loss of sand stone initial permeability while the loss is significantly... 

In order to investigate the feasibility and effects of core permeability on capillary imbibition recoverable oil from carbonate cores, some laboratory tests were carried out at the EOR research laboratories of Sharif University, Iran. Outcrop rocks with different permeabilities were taken away from a recognized outcrop and used in these experiments. Special core analysis tests were run on two core samples to find out relative permeability and end point saturations. Wellhead separator oil and gas samples were collected and recombined to a reservoir gas - oil ratio. A core flooding system with a capability of free and forced imbibition testing was designed and installed. A number of free and...