METHOD FOR LIMITING WATER INFLOW AND GAS BREAKTHROUGH IN PRODUCTION BOREHOLES AND GEL-FORMING COMPOSITION FOR THE IMPLEMENTATION THEREOF Russian patent published in 2022 - IPC E21B33/138 E21B43/32 C09K8/512 

FIELD: petroleum industry.

SUBSTANCE: in the method for limiting water inflow and gas breakthrough in production boreholes using a gel-forming composition based on polyvinyl alcohol and boric acid, the gel-forming composition is injected into the production borehole in alternating rims of the gel-forming agent and the crosslinking agent in a volume ratio from 1:1 to 15:1, capable of forming gels directly in the layer, wherein a buffer water rim of 1 to 2 m³ is injected between the rims of the gel-forming agent and the crosslinking agent, wherein the first rim is the gel-forming agent and the last rim is the crosslinking agent. After injecting the last rim, the gel-forming composition is pushed into the layer from the tubing string with a buffer volume of water of 8 to 10 m³. The borehole is then closed and held from 12 hours to 1–3 days. The gel-forming agent contains, wt.%: polyvinyl alcohol PVA 3 to 7; boric acid 1; glycerine 0 to 50; water the rest. The crosslinking agent contains, wt.%: borax decahydrate or hexahydrate 2.5 to 10; glycerine 20 to 50; water the rest.

EFFECT: limited water inflow and gas breakthrough in production boreholes of collectors with different permeability, including for carbonate rocks saturated with high-viscosity petroleum.

1 cl, 8 dwg, 3 tbl