Pore-scale dissolution of CO2 + SO2 in deep saline aquifers

We employ Modified Moving Particle Semi-implicit (MMPS) method to study the multi-ion transport of CO2 and SO2 in natural porous media at the pore level. A new approach has been developed to account for the electrostatic forces. Compared to solving the Poisson-Nernst-Planck equations, this new approach eliminates the restrictions on the size of time step and hence allows for faster simulations. We carry out a series of simulations to study the dissolution of different charged and neutral species resulting from the injection of pure CO2 and CO2 + SO2 in two sandstones, namely Berea and Bentheimer. The pressure, temperature and salinity conditions resemble those encountered in deep saline aquifers and non-ideality of the solution is taken into account by using the Davies activity model. We investigate the impact of pore-space topology on the dispersion of different ions in both cases of pure CO2 injection and CO2 + SO2 co-injection. Impact of the electrostatic forces on distribution of different ions in the samples is thoroughly studied. (c) 2013 Elsevier Ltd. All rights reserved.