METHOD FOR INCREASING HYDROPHILICITY OF CARBONATE RESERVOIRS Russian patent published in 2023 - IPC E21B43/25 E21B43/22 E21B43/27 C09K8/60 

FIELD: oil industry.

SUBSTANCE: methods for increasing oil recovery from carbonate reservoirs by improving the filtration properties of the bottomhole zones of oil and gas wells. A method for increasing the hydrophilicity of carbonate reservoirs involves sequential injection of sodium-containing elements and a reaction agent with sodium-containing elements with overflush with the release of chemical reaction products. Wells are preliminarily selected with a water cut of production on average over the area of no more than 90% and a permeability in the bottomhole zone of the formation of at least 100 m³/day. Selected wells are sequentially injected with sodium-containing elements, for which sodium metal is used in the form of granules, enclosed in an alkali-soluble protective shell, and a reaction agent - sodium hydroxide in a ratio of 1:1.5, respectively. Further injection into the formation is carried out by the fluid of the reservoir pressure maintenance system. In this case, the protective shells are made of aluminum.

EFFECT: increase in oil recovery by reducing the interfacial tension at the oil-rock boundary and the impact on the carbonate reservoir through the use of low-aggressive reagents, improving the filtration and capacitance properties of the bottomhole zones of wells and interwell spaces of the formation, preventing premature corrosive wear of tubing.

1 cl