Acidizing formation is one of the most common methods of increasing or restoring well productivity. The article discusses the influence of various factors on the effectiveness of acid treatments. Factors that increase the risk of ineffective measures include the energy state of the formation – reduced formation pressure during operation, the ratio of the injected volume of acid to the volume of diverting fluid, low wellhead pressures during treatment, at which the acid composition is absorbed by natural cracks. The analysis of field data based on the results of acid treatments is presented, and the influence of the number of previously conducted bottom hole treatments (BHT) and technological indicators on the efficiency of BHT is assessed. After analyzing the treatments performed and identifying the dependencies of the geological and technological characteristics, model calculations were carried out on the Rockstim simulator of the three potentially effective technologies being analyzed: injection of self-diverting acid compositions, acid treatments with injection of fibers (including biofibers) and foam acid treatments. Based on the results of modeling on the Rockstim simulator, the best BHT designs were obtained, analyzed and selected, including sequences of stages, volumes and injection rates, taking into account maximum economic profitability for all technologies. Based on the results of the analysis, conclusions were drawn about possible directions for increasing the efficiency of acid treatments of wells.
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