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A fragment of indole compounds under inhalation action on experimental animals is presented

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Cenomanian gas deposits account for about 80% of natural gas production in Russia. Today, mature Cenomanian gas fields are depleted by more than 75% on average, the reservoir pressure in the productive formation zone has decreased by almost 90% compared to the initial pressure and in some places reaches 1.0-1.5 MPa. Reduction of pressure in the pay zone leads to active intrusion of water from the aquifer. The liquid is loading the well, and gas production decreases. The technology of gas well operation with foaming agent is widespread in the world, which is characterized by a high level of efficiency, including economic. The use of technology leads to a solution to the liquid loading and requires a preliminary selection of the optimal concentration of surfactants. The optimal concentration should ensure the creation of a relatively stable foam and provide a minimum pressure gradient in the production tubing. The article presents the results of studies of CTAB foaming agent influence on the process of liquid removal and pressure gradient in production tubing. Sequential studies to determine CMC, foamability, foam stability, and pressure gradient under foam flow were conducted on small-scale and large-scale facilities. These results can be reliable when using CTAB foaming agent, foaming agents based on it, or other cationic foaming agents in Cenomanian gas wells under the condition of reservoir water inflow. Besides, the effect of pressure on the optimal concentration of the foaming agent was also studied in this work.

Using BU161-4 formation of the Urengoy oil and condensate field deposit as an example the authors have demonstrated that today in the absence of developed transport infrastructure high CAPEX and OPEX investments are inevitable. It will result in negative economic results in developing oil banks in gas and condensate deposits located in the Northern and Polar regions of the Russian Federation. This factor decreases attraction of such assets for investors significantly and actually oil reserves in oil banks and gas reserves in gas caps are not developed and it is uncertain when these reserves might be developed. As a result the state will get less revenue from developing hydrocarbon reserves.