Coupled Reactive Transport Model for Heat and Density Driven Flow in CO2 Storage in Saline Aquifers

In this paper, a novel reactive diffusion-convection transport model is proposed to investigate the flow during different CO2 trappings in deep saline aquifers. Dissolved and immiscible CO2 have trapping times ranging from 1 million to several million years. The mineral trapping has a much longer temporal scale than the solubility trapping. The fine resolution of diffusion-to-advection characteristics is mapped by a corresponding implementation of finite-element numerical simulation. The diffusivity and reaction rate has prominent effects on diffusion-convection-reaction behaviors of the CO2-brine system. The 2-D numerical solutions give insight into the trapping evolution of injected CO2 in a deep subsurface environment.