Pore‐scale trapping of supercritical CO2 and the role of grain wettability and shape. Issue 15 (1st August 2013) - Chaudhary, Kuldeep
Abstract: [1] The capillary trapping of supercritical CO2 (s‐CO2 ) is postulated to comprise up to 90% of permanently trapped CO2 injected during geologic sequestration. Successive s‐CO2 /brine flooding experiments under reservoir conditions showed that water‐wet rounded beads trapped 15% of injected s‐CO2 both as clusters and as individual ganglia, whereas CO2 ‐wet beads trapped only 2% of the injected s‐CO2 as minute pockets in pore constrictions. Angular water‐wet grains trapped 20% of the CO2 but flow was affected by preferential flow. Thus, capillary trapping is a viable mechanism for the permanent CO2 storage, but its success is constrained by the media wettability. Key Points: Novel evidence of CO2‐wet media controls on capillary trapping of CO2 Evidence of CO2‐wet media will critically limit its capillary trapping potential Capillary trapping of CO2 will be a viable mechanism in water‐wet media