Interactions Between Stratigraphy and Interfacial Properties on Flow and Trapping in Geologic Carbon Storage

Abstract

Gas leakage from geologic carbon storage sites could undermine the long‐term goal of reducing emissions to the atmosphere and negatively impact groundwater resources. Despite this, there remain uncertainties associated with the transport processes that would govern this leakage. These stem from the complex interaction between governing forces (e.g., gravitational, viscous, and capillary), the heterogeneous nature of the porous media, and the characteristic length scales of these leakage events, all of which impact the CO2 fluid flow processes. Here we assessed how sub‐basin‐scale horizons in porous media could impact the migration and trapping of a CO2 plume. A high‐pressure column packed with two layers of sand with different properties (e.g., grain size and wettability) was used to create a low‐contrast stratigraphic horizon. CO2 in supercritical or liquid phase was injected into the bottom of the column under various conditions (e.g., temperature, pressure, and capillary number) and the transport of the resulting plume was recorded using electrical resistivity. The results show that CO2 trapping was most strongly impacted by shifting the wettability balance to mixed‐wet conditions, particularly for residual saturation. A 16% increase in the cosine of the contact angle for a mixed‐wet sand resulted in nearly twice as much residual trapping. Permeability contrast, pressure, and temperature also impacted the residual saturation but to a lesser extent. Flow rate affected the dynamics of saturation profile development, but the effect is transient, suggesting that the other effects observed here could apply to a broad range of leakage conditions.

Immiscible fluid displacement in porous media with spatially correlated particle sizes

“…The occurrence of structural heterogeneity, in the form of high permeability zones within aquitards, can also compromise their ability to act as barriers for water and contaminant migration [60]. In addition, the contrast in permeability between different geological layers may control the mechanisms for attenuation of CO 2 , when considering leakage from an underground reservoir used for carbon capture and storage [43,51,32]. These studies show the importance of considering the structural heterogeneity of porous materials, due to their impact on flow rates and fluid phase distribution.…”

Targeted Permeability Control in the Subsurface via Calcium Silicate Carbonation

“…Geophysical and/or geochemical alteration of the subsurface environment can create new and undesirable pathways for fluid migration. , In EGS, these are often referred to as thief zones, and undermine the economic viability of production. In GCS, leakage can contribute to groundwater contamination . In addition, the influence that fluid migration has on induced seismicity remains problematic and difficult to predict. − …”

“…In GCS, leakage can contribute to groundwater contamination. 12 In addition, the influence that fluid migration has on induced seismicity remains problematic and difficult to predict. 13−16 Strategies to control undesirable fluid migration are limited.…”

Numerical modeling of geological carbon sequestration : enhanced dissolution in randomly heterogeneous media

“…The injected super critical CO 2 may have the potential to escape from the deep reservoir formation to the shallow aquifer and finally atmosphere (Lindeberg and Bergmo, 2003;Juanes et al, 2006;Krevor et al, 2011;Liang and Clarens, 2018). We thus need to evaluate the impact of leakage on the local environment close to reservoir site.…”

“…Third, the pore-scale behavior, which is mainly related to the capillarity and relative permeability, is also obtained in the laboratory. Recent experimental studies extend the famous Brook-Corey and van Genuchten models by investigating the effect of hysteresis of the drainage and imbibition paths (Land, 1968;Agarwal, 1967;Spiteri et al, 2008;Krevor et al, 2012;Liang and Clarens, 2018). More experimental studies are related to the dissolution process due to gravity-driven convection and the intrusion process of CO 2 (Li et al, 2017b;Ramanathan et al, 2010;Zhang et al, 2011a;Trevisan et al, 2017;Wang et al, 2021).…”