RE-CROSS-LINKED GEL PARTICLE FOR CONTROL OF CO COVERAGE AND CO LEAKAGE BLOCKING Russian patent published in 2022 - IPC C08L33/26 C08K3/30 C08K5/98 C08K5/16 C08F218/08 C08F220/38 C08F220/56 C08J3/75 C09K8/12 

FIELD: oil industry.

SUBSTANCE: group of inventions relates to a composition of gel particles for CO₂-EOR (method for increasing oil recovery) and CO₂ storage, which can be re-cross-linked in underground conditions. These gel particles can be used for improvement of coverage, when injecting CO₂ into a reservoir, cyclic pumping of CO₂ steam, or alternating injection of water and gas (WAG). A composition capable of swelling for control of a liquid flow is described, containing at least 50 weight percent of a polymer matrix, less than 20 weight percent of the first cross-linking agent, and less than 20 weight percent of the second cross-linking agent, where the specified polymer matrix contains at least 40 molar percent of the first monomer containing a re-cross-linked fragment, at least 0.5 and less than 50 molar percent of the second monomer containing an acid-resistant fragment, and at least 1 and less than 50 molar percent of the third monomer containing a CO₂-philic fragment, where molar percent is given per the total molar content of the specified first monomer, the specified second monomer, and the specified third monomer. A method for the production of the specified composition capable of swelling, and a method for regulation or control of liquid present in an underground medium, including introduction of the specified composition capable of swelling into the underground medium, so that the specified composition capable of swelling contacts with liquid, are also described.

EFFECT: provision of gel particles, which can be re-cross-linked in underground conditions and save stability in supercritical CO₂.

45 cl, 1 dwg, 4 ex