Abstract:

To address the challenges of hydraulic fracturing in unconventional oil and gas reservoirs in terms of water resource consumption，formation damage of water sensitivity，and environmental pollution，this study systematically investigates the fracturing mechanism，application status，and engineering challenges of the supercritical carbon dioxide （SC-CO₂） fracturing technology. Compared with water-based fracturing fluids，SC-CO₂ is more likely to generate complex fracture networks because of its low viscosity，high diffusivity and near-zero interfacial tension. The mechanism of “modification-permeability enhancement” is clarified：SC-CO₂ reconstructs pore-fracture systems through mineral dissolution and organic matter extraction，while also degrading rock strength and increasing brittleness，which jointly facilitates fracture initiation and propagation. Recent advances in fluorine-/silicon-based thickeners，non-fluorinated thickening systems，and SC-CO₂ jet and compound fracturing technologies are summarized. Although challenges remain in proppant transport，equipment compatibility，cost control，and quantification of storage efficiency and leakage risks，SC-CO₂ fracturing shows strong potential for the integrated development pathway of fracturing，enhanced recovery and carbon sequestration in unconventional reservoirs.

Key words:

supercritical carbon dioxide, hydraulic fracturing, fracture propagation, rock mechanics, proppant carrying capacity

摘要：

针对非常规油气储层水力压裂面临的水资源消耗、水敏伤害及环境污染难题，系统论述了超临界二氧化碳（SC-CO₂）压裂技术的致裂机理、应用现状与工程挑战。与水基压裂液相比，SC-CO₂具有低黏度、高扩散性和近零界面张力的特性，更易形成复杂裂缝网络，其“改性-增渗”作用机制为SC-CO₂通过矿物溶蚀和有机质萃取重构储层孔缝系统，同时削弱岩石强度并提高脆性，从而协同促进裂缝起裂与扩展。同时，总结了含氟/硅基增稠剂、非氟增稠体系以及SC-CO₂射流压裂和复合压裂等技术的最新进展。尽管SC-CO₂压裂在支撑剂输送、装备适配性、成本控制以及封存效率与泄漏风险量化等方面仍面临挑战，但在非常规油气“压裂-增产-封存”一体化开发路径中展现出良好的应用潜力。

关键词:

超临界二氧化碳, 水力压裂, 裂缝扩展, 岩石力学, 携砂性能