Visualization experimental investigations of supercritical CO2 inject into porous media with the fissure defect

Abstract

Experimental studies about supercritical CO2-brine displacement are necessary to understand the detailed flow process of injected supercritical CO2 in deep saline aquifers. This article adopts experimental method to research the supercritical CO2 and water flow in porous media, using MRI as visualization and measurement method. Supercritical CO2 and water are injected into the sintered glass porous media structure by different mixture ratios. The sintered glass porous media structure is designed with the fissure defect. Visualization and analysis results simultaneously demonstrate that supercritical CO2 saturation and distribution vary with different ratios. The CO2 saturation increases with elevation in CO2-water ratio. And the CO2 distribution is significantly influenced by the buoyancy force and the supercritical CO2 will tend to migrate to the top of the test section. This paper also investigates the fissure effect. More supercritical CO2 will migrate to the top when encounters the fissure defect, and therefore the cap rock has to withstand bigger pressure, which will reduce the safety of carbon geological storage.