Pore scale modelling of calcite cement dissolution in a reservoir sandstone matrix

Abstract

Long-term evolution of permeability and tortuosity due to porosity changes evoked by reactivity of aqueous solutions is of paramount importance for predicting water-rock interaction. This challenge is best tackled by introducing reactive transport modelling on the pore-scale, where the modeling domain is a high-resolution tomographic image of the porous media. We suggest to use a voxel based Navier-Stokes-Brinkman solver in a finite volume formulation coupled to the thermodynamic equilibrium code PhreeqC. High-performance parallelized computations using this coupled numerical reactive transport solver are performed directly on the voxel grid of the segmented micro-CT scans. Retreat of the calcite cement in a sandstone matrix due to dissolution reactions can be directly visualized by digital rock physics experiments.