This paper presents the results of the phase behavior studies of asphaltenes in reservoir oil samples from the Timan-Pechora oil and gas province. Experiments were conducted to determine the pressure at which asphaltene precipitation begins depending on the specified temperature and pressure conditions. The studies were carried out by recording the amount of solid particles formed as a function of pressure at a fixed temperature using a high-pressure microscope. It was found that asphaltenes in reservoir oil collected from the D1op1 formation at the fields of the Timan-Pechora oil and gas province are stable in the pressure range from reservoir pressure to saturation pressure at temperatures of 45– 90 ºC. Additionally, based on the PVT model, an assessment was made of the risks of asphaltene precipitation during injection of model gas (methane). It was found that for a mixture of the original reservoir oil with methane with a gas concentration of 46,87 % mol. at reservoir temperature in the pressure range of 38,27–42,46 MPa, risks of precipitation of the asphaltene solid phase may arise. The obtained results of laboratory studies can enable to predict the behavior of the fluid in reservoir conditions and reduce uncertainties in choosing a strategy for designing and operating fields, and using various methods of enhanced oil recovery.
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