Linear perturbation analysis of density change caused by dissolution of carbon dioxide in saline aqueous phase

From a quantitative analysis on the onset of instability, it is found that the system is more stable when the viscosity increases more rapidly with concentration. In addition, parametric analysis of density-concentration relationship shows that the form of density-concentration relationship affects the prediction of onset of instability. In this way, concavity of density-concentration function decreases the weight of the top layer and lowers the destabilizing effect of the layer. These findings provide a more realistic outlook to recognize the onset of convection and long-term fate of disposed gas in large-scale geological sequestration of CO2.