Optimizing Capillary Trapping as a Carbon Dioxide Mitigation Strategy: Pore-Scale Findings in Support of Larger-Scale Implementation
By Dr. Dorthe Wildenschild, Associate Professor in Chemical, Biological, and Environmental Engineering at Oregon State University.
Dr. Wildenshchild is this year's Darcy lecturer for the National Groundwater Association.
Discover how x-ray microtomography is being studied for possible use as a technique to optimize capillary trapping of carbon dioxide in this presentation. Capillary trapping is a mechanism supporting carbon capture and storage (CCS), which is being considered as a mitigation strategy for emissions from concentrated sources such as coal-fired power plants.
Initial work using x-ray microtomography has focused on proxy fluid-based systems and experiments carried out at ambient conditions. As the interfacial tension, viscosity, and carbon dioxide injection (as well as subsequent brine flood injection) rates are varied, trends have been observed with the type of porous medium (unconsolidated vs. consolidated), varying wetting and nonwetting phase viscosity, and flow rates. The latter in particular has been investigated for its effect on morphology and connectivity of the trapped nonwetting phase (i.e., the supercritical carbon dioxide).
Results so far indicate that carbon dioxide injection can be manipulated to facilitate optimal trapping of residual carbon dioxide, both in terms of amount and with respect to size/ connectivity characteristics that may favorably support subsequent trapping reactions (e.g., dissolution and mineral formation).
200 University Avenue West
Waterloo, ON N2L 3G1