The formation of organic deposits as paraffins and asphaltenes on the rock and equipment surface leads to a deterioration of reservoir properties of formation, complications in the operation of downhole pumping equipment and, as a result, a decrease of oil production. In this regard, it is an important task to develop reliable approaches and tools for predicting of forming of these depositions. These approaches are implemented by phase diagrams construction taking into account wells thermobaric conditions and oil treatment facilities or thermodynamic models which based on equations of state using experimental data for tuning. For the successful application of both approaches, it is extremely important to develop reliable methods of experimental investigations of the phase behavior of paraffin in reservoir fluids samples.
The article considers the possibilities of application of experimental methods for reservoir oil phase behavior studying to identificate thermobaric conditions characterized by an increased risk of paraffin deposition. The saturation pressure and the wax appearance temperature of oil under study were determined experimentally, depending on thermobaric conditions. Investigation of the conditions of the solid paraffin phase deposition was carried out by recording the amount of formed solid particles from temperature at a fixed pressure using a high-pressure microscope. Based on the results obtained, the authors constructed a phase diagram combined with thermobarimetric measurements in the well, depending on its depth. The areas of increased risk of complications in the studied well were assessed. The proposed approach can be used in the economic and technological justification of the applied methods for the prevention and removal of paraffin deposits in the fields.
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