Influence of Heterogeneous Capillary Pressure on CO₂ Sequestration in Different Wetting Conditions

In heterogeneous capillary pressure fields, a number of capillary barriers can exist and CO₂ accumulates below them. This phenomenon is regarded as capillary trapping for CO₂ sequestration. To analyze the amount of CO₂ trapped and leakage, wettability as well as heterogeneity should be taken into account. Numerical simulations are undertaken to estimate the quantity of CO₂ trapped by dissolution, residual, and capillary trapping under different heterogeneity and CO₂/brine wettability scenarios. As the permeability variation increases, the amount of CO₂ leakage decreases. In strongly water-wet system, the largest portion of stored CO₂ is immobilized securely.