Enhanced Removal of Brine From Porous Structures by Supercritical CO2

Abstract

Supercritical CO₂ (sCO₂) removes water from brine held in pumice stone at levels well above the solubility of water in sCO₂. The higher water removal results from a combination of passive emulsification of water in sCO₂ and viscous fingering of sCO₂ through the saturated pumice. This leads to higher levels of salt deposition than that expected from solubility considerations alone. These deposits could impact the injectivity of sCO₂ as well as its movement in the subsurface. The finding that the water concentration in sCO₂ is not necessarily capped at the solubility limit should influence the parametrization of injection models.