In the article problem of wellbore & near wellbore zone acid-oil emulsion during well treatment are reviewed. Content of the heavy components of oil from various Bashkortostan’s reservoirs are analyzed. The advantage of the technology of acid treatment with the use of a complex modifying additive (CMA) in the composition of hydrochloric acid is justified in comparison with the basic acid treatment for the geological and physical conditions of the studied reservoirs. CMA composed of mixture two-component mutual solvent, complex cationic surfactant & organic acid. Researches by definition of surface tension at the new acid system-oil interface, new acid system and oil compatibility, dissolution velocity of reservoir carbonates by new acid system with different CMA concentration at reservoir conditions were conducted. The dependence of interfacial tension as a function of the CMA concentration in the new acid system was shown. The results of determination of the compatibility of “basic acid system” and oil shows derived necessity of using “new acid system” as most compatible & less problematic for well treatment oil emulsion issue. Derived dependency of the reaction rate of the new acid system with carbonates on the CMA concentration that is parabolic. Kinetics parameters of “new acid mix” reaction with reservoir carbonates are calculated. By core tests at reservoir conditions demonstrated issue severity of acid-oil emulsion & efficiency of “new acid system” in prevention of the issue.
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