Numerical and Experimental Investigation of Natural Convection Flow of (Sub-) and (Super-) Critical CO2 in Aqueous Phase

R. Khosrokhavar[1], G. Elsinga[1], R. Farajzadeh[2], H. Bruining[1]
[1]Delft University of Technology, Delft, The Netherland
[2]Shell International Global Solutions, Amsterdam, The Netherland
Published in 2012

Optimal storage of carbon dioxide (CO2) in aquifers requires dissolution in the aqueous phase. Transfer of CO2 from the gas phase to the aqueous phase or oil phase would be slow if it were only driven by diffusion. Dissolution of CO2 in brine (oil) forms a mixture that is denser than the original brine. This causes a local density increase, which induces natural convection currents accelerating the rate of CO2 dissolution. This study presents numerical models in bulk fluids to simulate a set of high pressure visual experiments based on the Schlieren technique, in which we observe the effect of gravity-induced fingers when sub- and super-critical CO2 is brought above a liquid at in situ pressures and temperatures.