EVALUATION OF METHODS TO MEASURE IN SITU CONTACT ANGLES OF SUPERCRITICAL CO2 AND BRINE IN SANDSTONE CORES USING MICRO-CT IMAGING

Using contact angle measurements to characterize fluid wettability is essential to understanding multiphase fluid behavior and storage capacity for potential Geologic Carbon Storage formations. The contact angle is the angle between two tangent lines (liquid-gas and liquid-solid interfaces) that meet at the three-phase contact point. Ongoing research at the U.S. Department of Energy National Energy Laboratory builds on past research extending to more representative reservoir conditions to obtain accurate contact angle measurements. Three-dimensional images of a sandstone sample at residual conditions reveals scCO₂ trapped in the pore network. scCO₂ volumes are isolated, image processed, and analyzed using multiple approaches. A comparison of contact angle measurements methods was completed to determine the most precise, time efficient process from which to build an automated contact angle measurement algorithm. Measurements completed on data in a resampled plane were in good agreement with measurements completed over multiple plane-views.