Short- and Long-Term Responses of Reservoir Rock Induced by CO2 Injection

Kim, Kiseok; Makhnenko, Roman Y.

doi:10.1007/s00603-022-03032-1

Cited by 10 publications

(1 citation statement)

References 93 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With the contact angles reported here and knowledge of the scCO 2 -brine IFT at subsurface conditions, Hg-air capillary pressure measurements can be converted to subsurface scCO 2 -brine conditions : During the short-term experiments, the predominant geochemical reactions were directed toward altering carbonate minerals, leaving the capillary properties of the quartz-rich sandstone largely unaffected within the experimental duration. The sandstone exhibited minimal reactivity, which aligns with findings in similar studies conducted over comparable timeframes and under analogous experimental conditions [91,[117][118][119][120]. It is conceivable that extended treatment periods (0.5-1.5 years) might reveal some level of reactivity with quartz [69,104], although this is less likely to substantially influence surface wettability, as suggested by the consistently unaltered contact angles reported in this study.…”

Section: Discussionsupporting

confidence: 89%

Effect of Geochemical Reactivity on ScCO2–Brine–Rock Capillary Displacement: Implications for Carbon Geostorage

Cruz,

Dang,

Curtis

et al. 2023

Energies

View full text Add to dashboard Cite

The displacement efficiency of supercritical CO2 (scCO2) injection in the storage zone and its primary trapping mechanism in the confining zone are strongly tied to the capillary phenomenon. Previous studies have indicated that the capillary phenomenon can be affected by geochemical reactivity induced by scCO2 dissolution in formation brine. To quantify such changes, thin disk samples representing a sandstone storage reservoir, siltstone confining zone, and mudstone confining zone were treated under a scCO2-enriched brine static condition for 21 days at 65 °C and 20.7 MPa. Geochemical alterations were assessed at the surface level using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy and X-ray fluorescence. Before and after treatment, the wettability of the scCO2–brine–rock systems was determined using the captive-bubble method at fluid-equilibrated conditions. Pore size distributions of the bulk rocks were obtained with mercury injection capillary pressure, nuclear magnetic resonance, and isothermal nitrogen adsorption. The results indicate the dissolution of calcite at the surface, while other potentially reactive minerals (e.g., clays, feldspars, and dolomite) remain preserved. Despite alteration of the surface mineralogy, the measured contact angles in the scCO2–brine–rocks systems do not change significantly. Contact angle values of 42 ± 2° for sandstone and 36 ± 2° for clay-rich siltstone/calcite-rich mudstone were determined before and after treatment. The rocks studied here maintained their water-wettability at elevated conditions and after geochemical reactivity. It is also observed that surface alteration by geochemical effects did not impact the pore size distributions or porosities of the thin disk samples after treatment. These results provide insights into understanding the impact of short-term geochemical reactions on the scCO2–brine capillary displacement in the storage zone and the risks associated with scCO2 breakthrough in confining zones.

show abstract