The development of oil and gas fields can be complicated by forming gas hydrates at the bottom, in the downhole zone, and in wellbores. It is reliably known that gas hydrate issues during production occur in many Eastern Siberian fields characterized by low reservoir temperatures. Current research in this direction is limited to predicting the gas hydrates formation depending on the thermobaric conditions of well operation. The influence of salt solutions injection into the reservoir under the Chayandinskoye oil-gas-condensate field conditions (pressure and temperature) is studied in order to establish the boundary level of water mineralization preventing the hydrate formation. The calculation of equilibrium conditions for the formation of gas hydrates of the model gas of the Chayandinskoye field and mineralized water from water wells and formation water of the Srednebotuobinskoye field is compared with experimental data in high-pressure autoclaves, which established "safe" in terms of complete prevention of hydrate formation threshold concentrations of 16 wt. % and 20.1 wt. % at reservoir temperature 9 °С and pressures 13 and 30 MPa, respectively. The modes and criteria for nucleation and formation of gas hydrates in the flow and in the static mode are determined using a slim-tube model of two-phase flow of model gas and water of varying salinity. The final result in this work was the determination of a threshold level of brine salinity guaranteeing the absence of hydrate complications of brines at the contact between the liquid phase and the gas-cap gas in the wellbore, ensuring a hydrate-free flow regime in the reservoir conditions of the Chayandinskoye field. The data obtained will form the basis of subsequent tests on core models to assess the risks of hydrate formation in the porous medium when salinity water is injected into the reservoir.
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