发表机构
Stanford University; Ghent University; University of Edinburgh; University of Manchester; Diamond Light Source; University of Southampton; Institute of Environmental Assessment and Water Research (IDAEA); Spanish Council for Scientific Research (CSIC)（斯坦福大学; 根特大学; 爱丁堡大学; 曼彻斯特大学; 钻石光源; 南安普顿大学; 环境评估与水资源研究所; 西班牙科学研究委员会）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究利用同步辐射X射线显微CT直接观测非均质砂岩中盐水驱替时的氢气迁移，发现即使低毛细管数下氢气团簇仍显著移动，强调孔隙尺度非均质性和瞬态滞留机制对储氢预测的重要性。
AI 中文摘要
在地下多孔地质构造中进行地下储氢是一种有前景的策略，用于平衡可再生能源发电与需求之间的时间错配。大规模储氢的可行性取决于在循环注入和采出操作期间预测氢气的分布、滞留和回收。然而，这些多相流过程受到岩石非均质性、毛细滞后和孔隙尺度滞留的影响。在本工作中，使用快速原位同步辐射X射线断层扫描直接可视化非均质砂岩中盐水驱替过程中的氢气迁移。通过系统改变盐水注入速率，量化了流动条件对氢气回收率及滞留氢气演变的影响。在驱替过程中观察到不连续氢气团簇的显著迁移，即使在低毛细管数（$<10^{-6}$）下也是如此。岩石非均质性影响了滞留行为，特别是在驱替早期阶段。我们的结果强调了将孔隙尺度非均质性和瞬态滞留机制纳入氢气储存预测的重要性。
英文摘要
Subsurface hydrogen storage in porous geological formations is a promising strategy for balancing temporal mismatches between renewable energy generation and demand. The viability of large-scale hydrogen storage depends on predicting hydrogen distribution, trapping, and recovery during cyclic injection and withdrawal operations. However, these multiphase flow processes are influenced by rock heterogeneity, capillary hysteresis and trapping at the pore-scale. In this work, fast in-situ synchrotron X-ray tomography was used to directly visualise hydrogen mobilisation during brine imbibition in a heterogeneous sandstone. By systematically varying the brine injection rate, the influence of flow conditions on hydrogen recovery, and the evolution of trapped hydrogen were quantified. Significant mobilisation of disconnected hydrogen clusters was observed during imbibition, even at low capillary numbers ($< 10^{-6}$). Rock heterogeneity influenced trapping behaviour, particularly during the early stages of imbibition. Our results highlight the importance of incorporating pore-scale heterogeneity and transient trapping mechanisms into hydrogen storage predictions.
