Linking Millimetre-Scale Heterogeneity to Rapid CO2 Migration in Reservoir Rock - segmented data

Experiments were conducted on a cylindrical core (50 mm in length and 25 mm in diameter) from the monitoring well at the GeoCquest Field Validation site in Australia. The sample was wrapped in a Viton sleeve and placed in an aluminium flow cell with two inlets and one outlet. The flow cell and tubing were secured to the micro-CT scanner to prevent movement during imaging, while differential pressure across the sample was monitored using a pressure transducer. Steady-state co-injection experiments were conducted at 8 MPa and 50C to replicate reservoir conditions. The non-wetting phase was CO2 and the wetting phase was carbonated brine (17 wt.% potassium iodine). Supersaturating the brine with CO2 prevented dissolution dynamics, which were beyond the scope of this research. A series of drainage fractional flow steps were acquired, with the proportion of the total flow rate contributed by the CO2 increasing. The fractional flow steps were fw = 0.5, 0.25, 0.1, and 0, where fw is the fraction of the total flow rate constituted by the brine. The total flow rate was 1 ml/min.