POWDER COMPOSITION FOR LIMITING WATER INFLOWS INTO WELLS AND METHOD FOR APPLICATION THEREOF Russian patent published in 2020 - IPC C09K8/588 E21B43/22 

FIELD: chemistry.

SUBSTANCE: invention relates to production of hydrocarbons, particularly, to limitation of water inflow to production wells. Powder composition for limiting water inflows in production wells, containing granules of hydrolysed polyacrylamide modified with ionizing radiation and trivalent metal salt, is a homogeneous mixture of granules with size of 0.05–2 mm and fluidity of not less than 20 % of bulk fluidity of quartz sand, wherein the composition contains, wt. %: granules of basic chromium sulphate 1–5 and granules of polyacrylamide, modified with ionizing radiation in dose of 1–12 kGy in composition, is the rest. Method of limiting water inflows in a production well by injecting a polymer-gel system into a formation through a tubular or annular space of the well, obtained by mixing said powder composition and acidified to pH less than 1.5 water at composition concentration of 0.5–5 wt. % and said water is the rest, pushing the polymer-gel system into the formation with a water-alkaline solution and/or formation water with holding in static conditions for at least 10 hours.

EFFECT: technical result is longer duration of effect of limiting influx of formation water into well.

2 cl, 1 tbl, 2 ex