METHOD OF WATER INFLOW LIMITATION IN FRACTURED CARBONE RESERVOIRS Russian patent published in 2017 - IPC E21B33/138 C09K8/50 

FIELD: oil and gas industry.

SUBSTANCE: method of water inflow shutoff in fractured carbone reservoirs includes preparation and injection of water shutoff composition consisting of aqueous solutions of polyacrylamide to the isolation zone and allowing the well to react. 5-15 m³ 10-15% of aqueous solution of polyaluminium chloride with pH=3,5-5 and 10-25 m³ of aqueous suspension of clay powder with density of 1080-1320 kg/m³ are injected successively in an insulated interval; specified pumping cycle is repeated from 1 to 5 times depending on injection capacity. After injection of required number of cycles 15m³ 10-15% water solution of polyaluminum chloride is additionally injected, injection is carried out continuously. Clay powder suspension injection is stopped at a sudden pressure increase, and only polyaluminum chloride aqueous solution is further injected in planned volume, and the well is withheld for reaction for 24-48 hours.

EFFECT: increased efficiency of water shutoff due to increased resistivity of insulating gel to pressure drops in fractured carbone reservoirs.

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