Research of a Self-Adaptive High-Performance Re-Fracturing Technology with Knot Temporary Plugging in a Thin Reservoir with High Stress

The K1g1 reservoir in the Jiudong Basin has many small thin layers, with strong interlayer heterogeneity and significant interlayer stress difference in the longitudinal direction. A low pumping rate and a large section of general fracturing were adopted in the early stage. The stimulation effect was unsatisfactory, and the production decreased rapidly. Therefore, improving the degree of longitudinal transformation is the key to the next fracturing. However, Complex conditions limited the selection of the layered fracturing technology. For example, the repeated fracturing wells have been perforated in large sections, the combination casing completion method is used, and the pumping pressure is high. This research summarized the applicable conditions of layered fracturing technologies. Combined with the geological conditions of Jiudong’s repeated fracturing wells, the temporary plugging layered fracturing technology is preferred. The temporary plugging agent is preferably the adaptive high-efficiency knot temporary plugging agent, and its degradation time experiment and ground plugging experiment are evaluated. The field application of adaptive high-efficiency knot temporary plugging re-fracturing technology was carried out in well C19-3. Based on three kinds of pressure rise performance during the fracturing process, it was judged that the fracturing obtained good temporary plugging and stratification effect. In addition, well C19-3 has achieved good production results after fracturing, which further verifies the applicability in the transformation of high-stress thin interbedded reservoirs in the Jiudong K1g1 reservoir. It provides ideas and references for the fracturing of similar thin interbedded reservoirs..