METHOD FOR DISPLACEMENT OF HIGH-VISCOSITY OIL FROM OIL DEPOSIT IN PERMAFROST ZONE Russian patent published in 2015 - IPC E21B43/22 

FIELD: oil and gas industry.

SUBSTANCE: in a method for the displacement of high-viscosity oil from an oil deposit in a permafrost zone including injection of a heated polymer solution through injectors, flushing of the polymer solution up to the bottomhole of the producer by brine water with the displacement of high-viscosity oil from the stratum with its further extraction and transportation through the producer hole to the surface, the hydrophobic polymer solution (HPS) is used and this HPS is obtained by gauging of water-methanol injection (WMI) with the ratio of water:methanol equal to 60:40 at the ratio of the water-soluble polymer:WMI equal to 1:1, HPS is heated up to the reservoir temperature and the ratio of its viscosity to the viscosity of lock oil is not less than 1:10 at the pressure of flushing that does not exceed the pressure of bottom water and gas cap, at that water-soluble cellulose derivatives or polyacrylamide or hydrolysed polyacrylonitrile are used as the water-soluble polymer.

EFFECT: ensuring the displacement of high-viscosity oil without the contamination of the production stratum and without thawing of permafrost rock surrounding the wells.