Numerical simulation of two-phase multicomponent flow with reactive transport in porous media: application to geological sequestration of CO2

Abstract

Dedicated to Amaia, for a long and happy life Abstract. In this work, we consider two-phase multicomponent ow in heterogeneous porous media with chemical reactions. Equations governing the system are the mass conservation law for each species, together with Darcy's law and complementary equations such as the capillary pressure law. Coupling with chemistry occurs through reactions rates. These rates can either be given non-linear functions of concentrations in the case of kinetic chemical reactions or are unknown in the case of equilibrium chemical reactions (such as reactions in aqueous phase). In this latter case, each reaction gives rise to a mass action law, an algebraic relation that relates the activities of the implied species. The resulting system will couple partial dierential equations with algebraic equations. The aim of this paper is to develop a numerical method for the simulation of this system. We consider a sequential approach that consists in splitting the initial problem into two sub-systems. The rst subsystem is a two-phase two-component ow, while the second subsystem is devoted to a reactive transport problem. For the two-phase two-component