METHOD TO INCREASE UNIFORMITY RECOVERY OF OIL RESERVES Russian patent published in 2016 - IPC E21B43/20 

FIELD: oil and gas industry.

SUBSTANCE: according to the method the deposit is developed by producing and injecting wells. To this end water is injected to injecting wells and product is extracted from producing wells. In order to reduce water inflow to producing wells various agents are injected to injecting wells. At that the site is selected with an injecting well in the centre. Upon flooding of one or several producing wells per more than 90% to flooded wells as well as to the injecting well water is injected with ion composition and /or salt concentration different from composition and/or concentration of brine water - modified water when all remaining wells at the site are shut for the period of injection. Composition of modified water is selected so that at its reaction with brine water sediment is precipitated in quantity sufficient to block pore channels in washed areas of the formation within radius of 10-100 m from the well. Consumption rate of modified water by the well is defined as 0.6-1.0 from maximum bed intake, and during injection - against injection pressure at least twice. To the first 5-10% of injected modified water agents inhibiting precipitation process are added. Upon injection of modified water waste water is injected to the injecting well. Producing wells are being operated at that. The operations are repeated at these and/or other wells of the site when similar water cut more than 90% is reached.

EFFECT: reduced water inflow to producing wells, increased uniformity of oil reserves recovery, increased coefficients of oil coverage and extraction.

2 ex, 1 dwg