CO2 Storage Trapping Mechanisms Quantification
The capture and storage of CO2 in deep geological formations is one of the proposed solutions to reduce CO2 emissions to the atmosphere. CO2 is injected as a supercritical fluid deep below a confining geological formation that prevents its return to the atmosphere. In general, four trapping mechanisms are expected, which are of increasing importance through time: (1) structural, (2) residual saturation, (3) dissolution, and (4) mineral trapping. The prediction of the mass of CO2 stored through time is an essential parameter in the pre-injection assessment of a geological storage. In this work, storage quantification in a synthetic 2D dome under different injection conditions has been performed by using multiphase transport simulations with COMSOL Multiphysics®. Model results predict well the amount of CO2 trapped as residual phase and the onset of the formation of CO2-rich brine fingers and their extent and evolution.