PROCEDURE FOR ELIMINATION OF ANNULUS CIRCULATION Russian patent published in 2016 - IPC E21B43/32 E21B43/20 E21B33/138 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil industry and can be used in production and injection wells, in which there is inflow or absorption of fluid in above- or underlying horizons. Method involves selection of production or injection well with inflow or absorption in above -or underlying aquifers relative to operated oil-bearing strata, well shutdown, pumping thereinto composition for restraint of water influx or water absorption, start of well in operation. Composition for limiting water influx or water absorption is modified with water, wherein composition and ion concentration of dissolved salts is determined from reduction of permeability of core aquifer at least 10 times when pumping one porous volume of core at formation temperature, wherein reduction of permeability is a result of precipitation of salts during reaction of modified water with brine water-bearing layer, in well is injected modified water heated to temperature of 40-100 °C at bottom and with flow rate of 0.5-1.0 of maximum capacity of water-bearing layer, total volume of injection is defined as 20-300 m³ per 1 m effective thickness of water-bearing layer, if necessary, preventing precipitation of salts in pumping equipment and pipes in first 2-5 % of total volume of injected modified water inhibitors are added, operations on injection of modified water are repeated at new flooding of production well with water from water bearing horizon at least to 95 % or higher intake capacity of injection well to a value greater than maximum capacity of productive oil formation.

EFFECT: high efficiency of elimination of annulus circulation in production and injection wells and prolonged effect.

1 cl, 1 dwg