METHOD FOR MUDDING FORMATION REMOVING FROM BOTTOMHOLE TERRIGENOUS FORMATION AREA Russian patent published in 2006 - IPC E21B43/27 

FIELD: oil production industry, particularly to stimulate production by forming crevices or fractures with the use of eroding chemicals.

SUBSTANCE: method involves injecting technological acid solution in bottomhole formation area; holding it in formation to provide reaction; removing reaction products from formation. The acid solution comprises acid and surfactant, wherein acid-surfactant reagent is used as the acid and the surfactant. The acid-surfactant reagent comprises surfactant in amount of 0.5-5.0% by weight, waterproofing agent in amount of 0.5-5.0% by weight, corrosion inhibitor or acetyl benzene or methyl ethyl ketone in amount of 0.1-3.0 % by weight, citric acid in amount of 1.0-10.0 % by weight, remainder is sulfonic acid. The technological acid solution comprises potassium persulfate or sodium persulfate in amount of 1.0-5.0% by weight, above acid-surfactant reagent in amount of 10.0-50.0 % by weight, remainder is water.

EFFECT: increased efficiency and improved technological effectiveness, prevention of secondary precipitations and emulsions formation.

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