Work

Thermal-hydro-mechanical-chemical coupling processes across scales in CO2 storage: Practices, challenges, and prospects

Year: 2026

Type: article

Abstract: Geological CO 2 storage, which involves the capture and long-term underground storage of CO 2 , is a critical technology in mitigating global climate change. This review systematically summarizes recent advances in CO 2 storage technologies, focusing on the fundamental mechanisms and engineering implications of multiscale coupled thermo-hydro-mechanical-chemical (THMC) processes. The interactions among thermal, hydrological, mechanical, and chemical processes are further integrated through coupled THMC effects, which are critical for assessing long-term storage integrity and system evolution. Understanding these controlling mechanisms informs the design of both current and emerging engineering applications, highlighting the dual role of CO 2 storage while jointly enhancing subsurface resource extraction (such as enhanced coalbed methane (ECBM) and enhanced oil/gas recovery (EOR)) and contributing to decarbonization targets (through dedicated CO 2 storage projects). Future perspectives emphasize gigatonne-scale CO 2 storage deployment and the integration of CO 2 storage with other sustainable technologies, such as CO 2 -based geothermal energy systems. Key environmental and operational challenges are also addressed, including the risks of leakage, and induced seismicity, together with challenges posed by complex behavior and heterogeneity contributing to reservoir uncertainties, and multi-site co-utilization interactions, all critical for ensuring safe and effective long-term storage. Emerging research directions include multi-scale THMC modeling, measurement-monitoring-verification (MMV) methodologies, and risk assessment empowered by machine learning and digital twins technologies. Deciphering multiscale THMC mechanisms constitutes the foundation for achieving long-term storage security and stability, while simultaneously advancing engineering synergies and climate objectives.

Source: Journal of Rock Mechanics and Geotechnical Engineering

DOI: 10.1016/j.jrmge.2026.06.004