The Research and Field Testing of Dual Temporary Plugging Fracturing Technology for Shale Gas Wells

Temporary plugging fracturing of shale gas wells has been challenged by the problems of insignificant temporary plugging pressure increases, the fact that the temporary plugging pressure sometimes does not transmit to the fracture, and sometimes unsuccessful combinations of inter-cluster temporary plugging and intra-fracture temporary plugging. Hence, a dual temporary plugging fracturing technology for shale gas wells was developed by adopting a GTF-SM differential pressure polymer-cemented temporary plugging agent and optimizing its dosage. It was also necessary to optimize inter-cluster temporary plugging and intra-fracture temporary plugging fracturing processes. This technology was tested for 10 stages in the staged fracturing of Well Jiaoye LQ-1HF in the Nanchuan Shale Gas Field. Compared with the stages treated with the conventional fracturing technologies, the temporary plugging pressure of the inter-cluster temporary plugging test section was increased by 4.3 MPa, and the temporary plugging pressure of the intra-fracture temporary plugging test section was increased by 0.82 MPa. The fracture length of the test section was increased by 5.8%, and the fracture area was increased by 12.5% on average. The well was tested with a ϕ10.0 mm choke, and the average gas production was 23.37×10⁴ m³/d, the average casing pressure was 20.17 MPa and the fluid production was 277.44 m³/d, which were advantageous over those of the conventional fracturing technologies. The test results showed that the dual temporary plugging fracturing technology for shale gas wells could form a better complex fracture network and enable the high-efficiency development and cost-effective fracturing of shale gas fields, hence showing a good value for wide adoption and application.