COMPOSITION FOR ACID TREATMENT OF CARBONATE RESERVOIRS Russian patent published in 2022 - IPC C09K8/74 

FIELD: oil industry.

SUBSTANCE: invention relates to the oil industry. The composition for acid treatment of carbonate reservoirs contains, by weight%: a mixture of alcohols 6.0-10.0; glacial acetic acid 1.5-2.5; a mixture of surfactants surfactants 1.5-2.5; oxy-ethylidendiphosphonic acid or nitrilotrimethylphosphonic acid 0.1-0.3; acid corrosion inhibitor "Soling" 0.15-0.4; hydrochloric acid with a concentration of HCl 22.8 mas.% - the rest. A mixture of two monatomic alcohols selected from the group isopropanol, methanol, propanol, butanol, in a mass ratio of 1:1 is used as a mixture of alcohols. A mixture of anionic surfactant and nonionic surfactant in the mass ratio of anioc surfactant:nonionic surfactant 1:2 respectively is used as a surfactant mixture.

EFFECT: compatibility of the composition for acid treatment with reservoir oils of various chemical composition and rheology, the possibility of regulating the reaction rate with the rock, preventing the formation of petroleum acid emulsions, including in the presence of trivalent iron in an amount from 2000 to 5000 ppm, increasing the temperature stability of the composition while maintaining the iron-stabilizing and demulsifying properties of the composition.

1 cl, 1 tbl, 3 ex