Integrated Uncertainty Quantification for Reactive Transport Modeling of CO2 Mineralization in Basalts

Summary Carbon capture and storage (CCS) is a viable approach to mitigate atmospheric CO2 emissions in relation to fossil fuel combustion. Mineralization of carbon dioxide in basaltic rock offers a permanent and stable entrapment of CO2, which has potential applications in various places worldwide. Reactive transport modeling is an essential tool for improving our understanding of basalt-water-CO2 interaction, plan and optimize existing and new storage sites. One of the main challenges in modeling reactive transport of CO2 in basalt is the large number of primary and secondary reactions and in the uncertainties associated with the input parameters. In this study, we introduce an uncertainty quantification approach that integrates a flow simulator, PHREEQC, with genetic optimization tools and Morris method for sensitivity analysis. Experimental data from the literature for basalt-water-CO2 interaction in a high-pressure column flow reactor is used to demonstrate the proposed approach.