The peculiarity of the initial opening of productive intervals makes it necessary to clean the bottomhole formation zone of the well before conducting hydrodynamic studies. The article presents the results of an extensive set of works on the selection of the optimal technology for acid treatment of an exploratory well in a high-temperature carbonate reservoir, confined to the Timan-Pechora oil and gas province. The paper presents the main geological and physical characteristics of the object under study, which also reduce the effectiveness of the acid treatment. The selection of an acid composition for conducting a well treatment was made taking into account the experience of working at an analogous field. The results of physicochemical studies to identify the risks of the negative impact of the acid composition on the rock, the study of the kinetics of the interaction of the acid composition with the rock and the physical modeling of acidizing are presented. A semi-empirical mathematical model of acid dissolution based on Damköller and Pecklet numbers and acid capacity was chosen to determine optimal treatment parameters (injection rate, acid volume) and develop recommendations for treatments. The treatment was performed using a high-tech tubing test assembly to combine all process operations in a single tripping operation, minimize time gaps between operations, eliminate the well killing stage after treatment, and eliminate risks associated with pulling the assembly out of the well after perforation of the pay interval. According to test results, the proposed solution showed its technological efficiency. The prospects for further development of this technology are outlined in relation to the geological and physical features of this reservoir.
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