Fracture initiation and propagation of supercritical carbon dioxide fracturing in calcite-rich shale: A coupled thermal-hydraulic-mechanical-chemical simulation

• DOI: 10.1016/j.ijrmms.2023.105389
• Publication Date: 2023-04-26T09:35:35Z
• Authors: Lin Wu; Zhengmeng Hou; Yachen Xie; Zhifeng Luo; Ying Xiong; Long Cheng; Xuning Wu; Qianjun Chen; Liangchao Huang
• Keywords: Fracture (geology); Carbon Dioxide Sequestration in Geological Formations; Environmental Engineering; FOS: Mechanical engineering; CO2 Sequestration; Engineering; Chemical engineering; Supercritical fluid; Petroleum engineering; FOS: Chemical engineering; Fracture Conductivity; Oil shale; Global and Planetary Change; Hydraulic Fracturing in Shale Gas Reservoirs; Mechanical Engineering; Physics; Calcite; FOS: Environmental engineering; Paleontology; Geology; FOS: Earth and related environmental sciences; Hydraulic fracturing; Mineralogy; Materials science; Fracture Propagation; Geotechnical engineering; Pore water pressure; Physical Sciences; Environmental Science; Global Methane Emissions and Impacts; Thermodynamics; Hydraulic Fracturing; Dissolution

The initiation and propagation mechanisms of supercritical carbon dioxide (scCO2) fracturing are more complex than those hydraulic in calcite-rich shale due to the temperature‒pressure sensitivity scCO2 scCO2-brine-rock interactions. In this study, we present an enhanced thermal-hydraulic-mechanical-chemical (THMC) simulator called CMPSF, which incorporates a rock damage model CO2 physical property into COMSOL-MATLAB-PHREEQC (CMP) coupling framework via MATLAB. Furthermore, procedure CMPSF is optimized from previous sequential non-iterative approach partly-iterative approach. We then utilize validated with numerical experimental examples analyze evolution THMC fields examine impact calcite content injection temperature on fracture shale. simulation results reveal that decreased mass fraction 1.5‰ porosity increment dissolution 0.33‰ at most within 12 min. A higher lead decrease pressure increase ratio. Specifically, as increases 50 wt% 80 wt%, decreases by 0.1 MPa, final ratio 0.25%. As 30 °C 60 °C, 4.3 1.55%. Calcite has minor early stage only perspective affecting seepage, its long-term effects require further investigation. Our findings provide insight processes