枯竭油气藏地下储氢技术挑战及展望

H2作为清洁高效的能源载体和燃料，面临大规模存储需求。盐穴、枯竭油气藏及含水层3种地下储氢库兼顾安全性与经济性，是目前可行性最高的解决方案，其中枯竭油气藏地下储氢最具发展前景。通过对比H2与CH4、CO2的物性差异，探讨了地下储氢的特殊性，重点梳理了枯竭油气藏地下储氢面临的技术挑战及应对策略：对于不稳定驱替与渗流扩散引起的气体泄漏，需控制注气速率，优化注采及垫层气布置方案，开展盖层突破压力、表界面特性及流动传质机理研究；对于耗氢的地球化学反应与微生物催化作用，选址应避免高含氢敏感性矿物、离子及微生物的地层，防止大量H2被消耗；对于圈闭与人工材料完整性失效问题，应基于地层宏观和微观的变形及破裂演化特征，评估地层损伤与气体泄漏风险，合理选材以加强人工设施抗腐蚀、抗氢脆性能。最后，指出了未来地下储氢技术研究的攻关方向，分别为多尺度多场耦合H2损耗机制研究、地下储氢场地尺度数值模拟研究、地下储氢气体运移及泄漏监测技术研究，以期为推动地下储氢工程实践提供参考。

Hydrogen, as an efficient energy carrier and clean fuel, has a demand for large-scale storage. At present, the underground hydrogen storage (UHS), in types of salt caverns, depleted oil and gas reservoirs and aquifers, is the most feasible solution balancing the storage security and economy. Specifically, the underground hydrogen storage in the depleted oil and gas reservoir is most promising among the three types. Herein, the particularity of underground hydrogen storage was discussed by comparing the difference of physical properties among H2, CH4 and CO2. In particular, the technical challenges and coping strategies for UHS in depleted oil and gas reservoirs were overviewed: (1) For the gas leakage caused by unstable displacement, seepage and diffusion, efforts should be made to control the gas injection rate, optimize the scheme of injection-production and cushion gas arrangement, and study the caprock breakthrough pressure, the surface interface characteristics and the flow and mass transfer mechanism. (2) For the hydrogen-consuming geochemical reaction and microbial catalysis, the strata with highly hydrogen-sensitive minerals, ions and microorganisms should be excluded from UHS potential sites to prevent unacceptable H2 consumption. (3) To cope with the integrity failures of traps and artificial materials, the risk of formation damage and gas leakage should be evaluated considering the macroscopic and microscopic deformation and fracture evolution characteristics of the formation. Besides, appropriate materials should be selected to enhance the resistance of artificial facilities to corrosion and hydrogen embrittlement. Finally, the directions of research on underground hydrogen storage technology were pointed out, including the research on H2 loss mechanism under multi-scale and multi-field coupling, the numerical simulation study on-site scale of UHS, and the gas migration and leakage monitoring technology in underground gas storage. Generally, this research could provide a reference for promoting the engineering practice of UHS. (5 Figures, 3 Tables, 73 References)