Acid compositions for enhanced oil recovery from carbonate reservoir

Abstract

© Published under licence by IOP Publishing Ltd. This work is devoted to selection of acidic compositions for use in the process of acid fracturing of carbonate oilfields. The selection is based on the stability of the compositions and their compatibility with oil and corrosion influence on oilfield equipment. The object of research was highly viscous bituminous oil and carbonate rock of Tatarstan Republic (Russian Federation). The object of research was oil and carbonate rock samples from the Vereian horizon of the Vishnevo-Polyanskoe oil field, which is characterized by oil containing in carbonate rocks. The chosen oil can be pertained to highly viscous bituminous oil according to its density and viscosity, what makes the process of its extraction from oil formations complicated. As the result there were selected two acid compositions which contained hydrochloric acid 15 wt %, demulsifier, dispersant, iron converter (for Fe3+ 2000 and 5000 ppm concentration) and corrosion inhibitor. The effectiveness degree of selected compositions was also demonstrated.