Hypergravity experiments on meter-scale porous media flow for geological carbon sequestration

Area of Science:

• Geological Sciences
• Environmental Engineering
• Chemical Engineering

Background:

• Reducing atmospheric carbon dioxide (CO2) is crucial for climate sustainability.
• Geological storage is a key strategy for long-term CO2 sequestration.
• Predicting subsurface CO2 behavior and migration is essential for safe storage.

Purpose of the Study:

• To investigate CO2 migration and behavior in subsurface geological formations.
• To provide experimental benchmarks for validating numerical simulations of CO2 sequestration.
• To assess the utility of geotechnical centrifuge experiments for CO2 storage research.

Main Methods:

• Conducted CO2 migration experiments using a geotechnical centrifuge at 50 G.
• Employed a pH-sensitive solution for CO2 plume visualization.
• Utilized a 12-sensor array for multilevel pressure monitoring during CO2 injection.

Main Results:

• Observed CO2 entry, gas cap formation, and subsequent vertical/lateral migration.
• Quantified pressure changes in central and flank sensors during different injection stages.
• Documented gravity-driven instabilities, secondary gas cap formation, and dissolution-induced pressure drops.

Conclusions:

• Centrifuge-based hypergravity experiments offer a viable method for studying CO2 sequestration.
• The study generated valuable quantitative datasets for benchmarking numerical models.
• Findings support the use of such experiments to improve predictions of subsurface CO2 behavior.