Characterizing the Effect of Capillary Heterogeneity on Multiphase Flow Pulsation in an Intermediate‐Scale Beadpack Experiment Using Time Series Clustering and Frequency Analysis

Abstract

CO 2 geologic storage is an essential part of climate change solutions. Not only can it allow our fossil-fuel dominated society to achieve carbon neutrality while transitioning toward more renewables, but when combined with biomass energy or direct air capture, CO 2 geologic storage is a key component of negative carbon pathways (IPCC, 2005(IPCC, , 2014Rogelj et al., 2018;Wilcox et al., 2021). One major target for CO 2 geologic storage is deep saline aquifers due to their large storage capacity and widespread availability (IPCC, 2005). However, in the sedimentary basins where these saline aquifers are located, the rock formations all have natural geologic fabrics (depositional textures at cm-to-m scales) that can be highly heterogeneous (Murphy et al., 1984;Rubin & Carter, 1987). Even small-scale heterogeneities (cm-scale) can significantly affect CO 2 migration and trapping (

Geologic Heterogeneity Controls on Trapping and Migration of CO2

“…Recent field observations (Chadwick et al., 2010; Dance et al., 2019; Hovorka et al., 2006), experiments (Jackson et al., 2018; Krishnamurthy et al., 2019; Trevisan, Pini, et al., 2017), and numerical simulations (Li & Benson, 2015; Meckel et al., 2015) suggest that residual trapping is only a fraction of the capillary trapped fluid (Gershenzon et al., 2017). Instead, CO 2 accumulates beneath sub‐seismic heterogeneities due to variations in capillary entry pressures (Ni & Meckel, 2021; Saadatpoor et al., 2010). These isolated accumulations are at much higher saturations than residual.…”

Effects of grain size and small-scale bedform architecture on CO2 saturation from buoyancy-driven flow

“…regimes with low flow rates), the nonwetting phase fluid migrates by pulsing and forms fragmented finger flow paths that have low saturation 45 , 50 . However, the nonwetting phase forms backfilled pools with high saturation when encountering baffles/capillary barriers 51 , 52 . Therefore, in Permedia’s MIP simulations, only the pools build up significant buoyancy pressure, while the fingers have negligible buoyancy pressure.…”