ACID COMPOSITION FOR TREATMENT OF BOREHOLE ZONE OF CARBONATE FORMATION Russian patent published in 2024 - IPC C09K8/74 

FIELD: oil production.

SUBSTANCE: invention relates to oil production and can be used for chemical dissolution of rocks and colmatage deposits in the wellbore zone of an oil, gas and gas condensate formation, and can also be used as process fluid in perforation and hydraulic fracturing. Acid composition for treatment of borehole zone of carbonate formation contains, vol.%: iron stabilizer “ТН-СЖКС” grade B – a composition of organic acids, quaternary ammonium salts in organic solvent 1.5; water-soluble demulsifier 1.5; detergent surfactant “ССА 05-23” or “ТН-МС-2” -– a composition of anionic and nonionic surfactants in a water-alcohol solution and alcohol 1.5; acid corrosion inhibitor “ТН-ИККС” grade С– mixture of nitrogen-containing reagents with active additives in water-alcohol solution 2.0; aqueous solution of synthetic hydrochloric acid of 12% concentration 50.0; fresh process water – balance. Water-soluble demulsifier used is “ТНХС-ДЭ” grade 408К– a mixture of polyesters, quaternary ammonium salts, oxyalkylated amines in organic solvents or “ТН-ДЭ-10” of grade A – a mixture of surfactants in a combination of aromatic and water-alcohol solvents.

EFFECT: reduced solubility of carbonate rocks of the formation, rate of corrosion of oil-field equipment, surface interfacial tension at the boundary "rock-fluid", reduced value of wetting angle with the composition of the treated rock, wider range of variation of the rate of reaction of the composition.

1 cl, 2 tbl