One of the complications arising during the development of oil and gas fields is the formation of associated gas hydrate deposits in the trunk of producing oil wells. In the interval of sediment formation, a decrease in the velocity of the upward flow of the gas-liquid mixture is likely, or its complete stop, which negatively affects the technical and economic condition of the field being developed. In order to increase the effectiveness of preventing hydrate formation new method for predicting hydrate formation intervals under conditions of constant and periodic operation of electric centrifugal pumps is considered on the example of the Vyngayakhinskoye field. When developing this technique, algorithms for the distribution of pressure and temperature of the gas-liquid flow were used, taking into account the influence of heating/cooling submersible electric motor, the composition of associated petroleum gas, reservoir water salts and applied inhibitors. This technique is based on the calculation of pseudo-reduced pressures and temperatures, which can be used to take into account the influence of each component in a gas-liquid mixture. Using the developed methodology, the depth of hydrate formation was obtained at 22 wells of the Vyngayakhinskoye field. As a result of testing the technique on 7 wells, the convergence of the results was about 90%. Analysis of the results showed that the composition of associated gas and reservoir water significantly affect the predicted depth of formation of gas hydrate deposits. The approach described in the article can be applied to estimate and predict this depth, which will allow to correct the technological process associated with the operation of the well and reduce the negative impact on the production process and equipment.
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