[HSC05-P09] The research on the movement of CO2 solution in CO2 microbubble storage.
Keywords:Carbon dioxide Capture and Storage, Carbon dioxide Microbubble Storage, Fingering
Experimental procedures are as follows. Water tank (height: 30 cm, width: 50cm, thickness: 3cm) made of acrylic boards was used for experiments. The tank was filled with grass beads (1mm in diameter) and BTB solution. Permeability was measured by controlling the difference of hydraulic head between the left and right end of the tank and found to be 1.32*10^-2 m/s. We observed how CO2 dissolved water moves after CO2 microbubble water was injected. As a result, CO2 solution moved downward as time passed and the shape of CO2 solution showed fingering.
In the second experiment, we injected CO2 solution by controlling the horizontal groundwater flow rate. As a result, it was observed that CO2 moved downward while it moved leftward because of advection. In this experiment, whether fingering was observed or not was dependent on the rate of advection. In CCS, whether the fingering occurs or not possibly depends on the rate of groundwater flow and CO2 concentration and it has crucial effect on solubility trapping and mineral trapping. However, there have been few researches of numerical analysis that consider the fingering because of computational load. However, the result of our experiment suggests the importance of simulation including possible fingering processes.