Comparison of CO2 trapping in highly heterogeneous reservoirs with Brooks-Corey and van Genuchten type capillary pressure curves

TL;DR

This study compares how two different capillary pressure models, Brooks-Corey and van Genuchten, influence CO2 trapping simulations in highly heterogeneous reservoirs, highlighting significant differences in trapping and dissolution behaviors.

Contribution

It demonstrates the impact of capillary pressure curve choice on CO2 trapping simulations in heterogeneous reservoirs, emphasizing the importance of model selection.

Findings

Capillary trapping varies significantly between models.

Dissolution rates differ based on the capillary pressure approach.

Heterogeneity and hysteresis influence trapping dynamics.

Abstract

Geological heterogeneities essentially affect the dynamics of a CO2 plume in subsurface environments. Previously we showed how the dynamics of a CO2 plume is influenced by the multi-scale stratal architecture in deep saline reservoirs. The results strongly suggest that representing small-scale features is critical to understanding capillary trapping processes. Here we present the result of simulation of CO2 trapping using two different conventional approaches, i.e. Brooks-Corey and van Genuchten, for the capillary pressure curves. We showed that capillary trapping and dissolution rates are very different for the Brooks-Corey and van Genuchten approaches when heterogeneity and hysteresis are both represented.