Advances in thermo-hydro-mechanical-chemical modelling for CO2 geological storage and utilization

Geological storage and utilization of CO2 involve complex interactions among Thermo-hydro-mechanical-chemical (THMC) coupling processes, which significantly affect storage integrity and efficiency. To address the challenges in accurately simulating these coupled phenomena, this paper systematically reviews recent advances in the mathematical modeling and numerical solution of THMC coupling in CO2 geological storage. The study focuses on the derivation and structure of governing and constitutive equations, the classification and comparative performance of fully coupled, iteratively coupled, and explicitly coupled solution methods, and the modeling of dynamic changes in porosity, permeability, and fracture evolution induced by multi-field interactions. Furthermore, the paper evaluates the capabilities, application scenarios, and limitations of major simulation platforms, including TOUGH, CMG-GEM, and COMSOL. By establishing a comparative framework integrating model formulations and solver strategies, this work clarifies the strengths and gaps of current approaches and contributes to the development of robust, scalable, and mechanism-oriented numerical models for long-term prediction of CO2 behavior in geological formations.