In the practical implementation of fracturing technologies, many unaccounted factors and phenomena arise that affect the effectiveness of their application. The formation of sludge emulsions is one of the main problems that arise as a result of acid fracturing. Viscous emulsions and sludge can clog the formation and cause further deterioration of the permeability of the bottomhole zone, as well as create problems in the oil treatment. The problem of forecasting the formation of oil-acid emulsions and the corresponding technological risks is topical, taking into account the prospects of acid fracturing to improve the efficiency of oil production. There is a need to develop informative methods to predict and analyze the formation of oil-acid emulsions promptly and with great accuracy. As such a method, the article proposes a combination of the methods of IR-Fourier spectroscopy and rheological studies, which make it possible to evaluate the change in the properties of oil and oil-acid emulsions. The objects of the study were samples of field samples of oil from the Aksubayevo-Mokshinskoye, Vishnevo-Polyanskoye and Yamashinskoye fields of the Republic of Tatarstan and acid-oil emulsions prepared under laboratory conditions. As demulsifiers, we used an aqueous solution of a mixture of anionic, nonionic surfactants and ethylene glycol, as well as a mixture of block copolymers of ethylene and propylene oxides in an organic solvent. Based on the results of the studies, it was noted that the most durable structure of the oil-acid emulsion is characteristic of oil with a higher value of the aromaticity coefficient and a minimum value of the aliphatic coefficient. The influence of the demulsifier on the viscosity of the oil-acid emulsion is most significant in the range of shear rates up to the creep zone; in the zone of structure destruction, the demulsifier practically does not affect the viscosity. Continued research on emulsion systems based on the integration of IR-Fourier spectroscopy and rheological studies is promising and relevant, as it is aimed at reducing technological risks and improving the environmental friendliness of acid fracturing.
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