Development of hydrocarbon-based surfactant-acid systems for a complex effect on bazhenov formation rocks
This work presents the results of studying the dissolving ability of acetic acid in a non-polar aromatic solvent and water during the interaction with rock samples of bazhenov formation. It is classified as a difficult production zone with hard-to-recover reserves which has great potential for oil production. It has been shown that the dissolution processes of mineral and organic rock components extensively depend on the acetic acid concentration and the nature of solvents. Moreover, they are determined by the associated state of acetic acid. Using the method of IR-Fourier spectroscopy, the features of hydrocarbon solutions’ effect on the extraction of organic matter components from rocks, depending on content of reagents, are considered. It was found that the addition of isopropanol to hydrocarbon and aqueous solutions of acetic acid significantly reduces the intensity of dissolution processes. Based on the determination of esterification degree, presence of the esterification reaction was confirmed. This reaction leads to the partial binding of acid and alcohol during the ester formation and provides a significant retardation of dissolving effect of these compositions. Also, the possibility of regulating compositions’ dissolving ability in a wide range between different values by introducing surfactants has been demonstrated. The studied compositions can be used as the base for intensifying surfactant-acid systems with prolonged action which can have a complex effect on the minerals and organic matter of the bazhenov formation rocks.