PROCEDURE FOR SELECTIVE ISOLATION AND RESTRAINT OF WATER PRODUCTION INTO HORIZONTAL WELLS Russian patent published in 2009 - IPC E21B43/32 

FIELD: oil and gas production.

SUBSTANCE: invention refers to oil producing industry, particularly, to procedures of isolation and restraint of water production in horizontal boreholes of producing wells. The procedure consists in polymer pumping, in driving polymer solution, and in well shut-down for the period of polymer structure formation. Prior to pumping polymer solution into each interval, blocking fluid with optimal period of "life" is pumped into the well; further, specified volume of polymer is pumped into an isolated interval during this period of "life"; after the expiration of the period blocking fluid self-decomposes in volume required for filling the horizontal borehole from the bottomhole of the well to the nearest from the bottomhole boundary of interval of polymer solution treatment. Upon conditioning, decomposer of polymer is pumped into the well for the period of polymer structure formation in the latest treated interval; with water decomposer is further driven through into a reservoir to the nearest near-well zone and is conditioned there for the period of polymer decomposition.

EFFECT: increased efficiency of isolating water production in horizontal wells.

5 dwg, 1 ex