METHOD FOR OPERATION OF WELLS AT LATER STAGES OF DEVELOPMENT OF OIL AND GAS FACILITY Russian patent published in 2017 - IPC E21B43/14 E21B43/38 E21B43/40 

FIELD: oil industry.

SUBSTANCE: invention relates to oil and gas processing industry, particularly to development and operation of formations with reduced permeability as a result of technogenic action, low formation pressure and high water cut. Method involves pumping from producing formation through one well oil onto day surface. Separated water is discharged into formation using two pumps. Said pumps are installed at different depths. Using said pumps fluid is pumped from tightly isolated chambers. Lower of these chambers is communicated with formation, and top with day surface. Capacity of lower pump is chosen so as to ensure maximum allowable depression on formation, and its pressure characteristics provide lifting of liquid from lower chamber to top-mounted in upper chamber of dynamic level. Capacity of upper pump is chosen below capacity of lower pump by a value, required to lift dynamic level in top chamber per time unit, wherein there is gravitational separation of phases into oil and water. Controlled valve for discharging water from upper chamber into lower chamber is adjusted so that water discharge into formation occurs until dynamic level of critical lower value is achieved. Valve is actuated to close at the arrival of a signal on achieving design pressure.

EFFECT: technical result is minimisation of water cutting of oil and water discharge into formation without residual oil content.

1 cl, 1 dwg