К ислотное воздействие на карбонатные коллекторы в условиях низкого пластового давления

Abstract

Background Currently, the share of stranded oil in the total amount of hydrocarbon reserves of Russia is increasing. Development of stranded oil and gas reserves will maintain the level of hydrocarbon production for a long time. A considerable part of the residual, hard-to-recover hydrocarbon reserves of Tatarstan is contained in carbonate reservoirs. Productive deposits containing oil have complicated geological structure. The use of acid treatment on carbonate reservoirs can improve the efficiency of operation of these deposits. However, quite a large number of deposits belong to the category of small and are developed without flooding system, which leads to a significant reduction in reservoir pressure near the wellbore. The use of standard hydrochloric acid treatment of wells in these conditions is often ineffective. Thus the research aimed at increasing the efficiency of operation of oil deposits in carbonate reservoirs were carried out, which, of course, is an urgent problem. Aims and Objectives To increase the efficiency of acid treatment on carbonate reservoirs in the bottomhole of low tier wells. Methods There were conducted the field studies of the proposed method. The results of these recovery improvement measures were processed by analytical and mathematical methods. The Results Based on the concepts of the oil displacement mechanism from low-permeable carbonate reservoirs a method of bottomhole zone treatment is offered for low tier wells. Application of this method allowed to increase the recovery 2 ... 3 times higher in comparison with the conventional treatment, furthermore duration of acid treatment effect 3 ... 4 times longer. Conclusion Application of the proposed method for stimulation of carbonate reservoirs of the Bashkirian and Vereinian strata in case of low pressure reservoirs of Melekessian hollow will significantly improve the efficiency of oil fields development.