Features of improving the reliability and efficiency of gas separators of submersible installations of electric centrifugal pumps for the reservoir fluid production

In oil producing wells with high gas content, an increase in the efficiency of centrifugal pumps is achieved by equipping them with centrifugal gas separators, in which, before entering the pump intake, most of the free gas is taken from the pumped fluid and discharged into the annulus of the well. The efficiency of a centrifugal gas separator significantly depends on the size of the dispersity of the gas-liquid structure of the pumped fluid, on the diameters of gas bubbles, the water cut of the formation fluid, the presence of surfactants, and the pressure at the inlet and outlet of the pump. In the article, based on the analysis of the structural diagrams of the power part of gas separators of various manufacturers, the analysis of the gas-liquid mixture flow features in the separation chamber and the outlet device, recommendations are made for optimizing the separation chamber length and the gas separator head outlet design. Recommendations are proposed for changing the flow path to increase the efficiency of gas separation and reliability of operation. Explanations of the expediency of new design solutions based on empirical formulas and numerical simulations are proposed. It is shown what the information is most important and how it can be obtained in bench tests.

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