Simulating carbon dioxide geologic storage at pore scale in digital rock

For mitigating climate change, scientific and technological progress in carbon dioxide capture and geologic storage is needed. The advancement requires efficient computational frameworks for simulating carbon dioxide injection and mineralization. In this presentation, I will discuss our team’s research in pore-scale assessment of geologic carbon dioxide storage. For creating high-accuracy capillary network representations based on micro-tomography data of reservoir rock plug samples, we have developed and tested a digital rock simulation environment [1]. Once a capillary network model of a rock sample is created, we perform series of flow simulations at realistic reservoir conditions. Specifically, we investigate how super-critical carbon dioxide is displacing brine and quantify the saturation levels in representative rock samples [2]. Finally, we perform computational experiments for tracking the modifications caused by carbon mineralization across the connected pore space, simultaneously within each of the thousands of connected capillaries with the digital rock [3]. We observe that the carbon mineralization gradually reduces the diameter of capillaries over time and causes the porosity and permeability of the rock to degrade. Depending on flow conditions, local mineralization sites can clog up critical flow pathways in the capillary network. As a result, a rock might not achieve its full geologic storage potential. For validation and reuse of our digital rock framework by the scientific community, we have made our rock data and the simulation code available in public repositories. References - [1] R. F. Neumann, et al. “High accuracy capillary network representation in digital rock reveals permeability scaling functions”. Sci Rep 11, 11370 (2021). https://www.nature.com/articles/s41598-021-90090-0 [2] J. Tirapu Azpiroz, et al., “Enhanced carbon dioxide drainage observed in digital rock under intermediate wetting conditions”. Sci Rep 14, 15852 (2024). https://www.nature.com/articles/s41598-024-65920-6 [3] D. A. L. Vasquez, et al., “Simulating carbon mineralization at pore scale in capillary networks of digital rock”. Transp Porous Media (accepted). https://arxiv.org/abs/2407.04238