INTENSIFYING COMPOSITION BASED ON SURFACTANTS AND COMPLEXING AGENTS FOR CARBONATE AND MIXED RESERVOIRS Russian patent published in 2023 - IPC C09K8/74 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to compositions for treating the bottomhole zone of carbonate and mixed reservoirs and can be used in the process of intensifying the operation of injection and production wells, including under conditions of high reservoir temperatures. The intensifying composition for acid treatment consists of a base and a corrosion inhibitor, thiourea, in an amount of 0.01-1.0 g/l of the base, or an ampholytic surfactant Oxysurfactant A14.25 in an amount of 0.1-10.0 g/l of the base, or corrosion inhibitor, thiourea, in the amount of 0.01-1.0 g/l of the base and ampholytic surfactant Oxysurfactant A14.25 in the amount of 0.1-10.0 g/l of the base. The base comprises, mol/l of the base: chelating reagent disodium salt of ethylenediaminetetraacetic acid 0.1-0.7; pH regulator sodium hydroxide or potassium hydroxide 0.1-0.7; citric, or tartaric, or succinic acid 0.01-0.05; ammonium chloride 0.01-0.1; the rest is fresh water, up to a litre.

EFFECT: providing a prolonged reaction of the proposed composition with rock while minimizing the concentration of reagents in the composition and increasing the degree of formation of complexes with metal ions.

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