METHOD FOR LIMITATION OF WATER INFLOW TO WELLS AT THICK OIL DEPOSITS Russian patent published in 2017 - IPC C09K8/50 E21B33/138 

FIELD: oil and gas industry.

SUBSTANCE: method for limiting water inflow into wells at thick oil deposits involves pumping the water-insulating gel-forming composition into formation, containing the following components, wt %: sodium silicate 0.4-8.9%, potassium silicate 0.1-4.5%, chromium acetate 0.4-1.5%, the rest is water. After pumping the water-insulating composition in 1.5-3 hours later, alkali solution is pumped to restore permeability of the oil saturated intervals, pumping 10-20% aqueous solution of sodium hydroxide into the rim with volume not exceeding 0.1-0.2 pore volume of the bottomhole formation zone. The induction period for the gel-forming composition at the formation temperature is set to 3-6 hours. The break is chosen for 15-25 hours, during this time the composition completely transits from liquid to gel-like state.

EFFECT: increase the efficiency of oil displacement from formation by gel-forming compounds due to increased strength of said compositions to high formation temperatures, increased oil recovery coefficient, connection of oil-saturated low-permeability interlayers.

2 dwg, 1 ex