Chemical and Hydrodynamic Mechanisms for Long-Term Geological Carbon Storage

Geological storage of CO2 (GCS), also referred to as carbon sequestration, is a critical component for decreasing anthropogenic CO2 atmospheric emissions. Stored CO2 will exist as a supercritical phase, most likely in deep, saline, sedimentary reservoirs. Research at the Center for Frontiers of Subsurface Energy Security (CFSES), a Department of Energy, Energy Frontier Research Center, provides insights into the storage process. The integration of pore-scale experiments, molecular dynamics simulations, and study of natural analogue sites has enabled understanding of the efficacy of capillary, solubility, and dissolution trapping of CO2 for GCS. Molecular dynamics simulations provide insight on relative wetting of supercritical CO2 and brine hydrophilic and hydrophobic basal surfaces of kaolinite. Column experiments of successive supercritical CO2/brine flooding with high-resolution X-ray computed tomography imaging show a greater than 10% difference of residual trapping of CO2 in hydrophobic media compare...