This paper describes the essential features for the simulation of CO2 storage in saline aquifers. Important physical processes that occur during CO2 storage are addressed: solubility trapping, residual gas trapping, mineral trapping and caprock integrity. The paper shows how these modeling techniques can be used to design a CO2 storage process in saline aquifers.
The following results are obtained: Solubility trapping and residual gas trapping are competing mechanisms. Residual gas trapping is important in low-permeability aquifers and water injection can be used to accelerate and enhance residual gas trapping. Mineral trapping is a very slow process and depends on the mineralogy of the aquifers. Geomechanics calculations coupled with the flow simulation can be used to predict potential failure of the caprock and subsequent leakage of CO2 to upper formations.