Keynote Session
Coupled Thermal-Hydrodynamic-Chemical-Mechanical Processes Modeling for Caprock Integrity in CO2 Geological Storage
- Prof. Tianfu Xu
- Jilin University
Biography
Tianfu Xu is currently a professor at Jilin University of China. He has been working at Lawrence Berkeley National Laboratory (LBNL) of USA for 16 years, in which he joined in 1996, initially as post-doctoral fellow, then become a scientist, and staff scientist. He received a bachelor’s degree in 1984 from Jilin University, an M.S. degree in 1993 from Delft University of Technology of The Netherlands, and a Ph.D. in 1996 from University of La Coruña, Spain. For the last 30 years, Tianfu has been working on developing new approaches to modeling multiphase non-isothermal fluid flow and chemical transport in unsaturated and saturated porous media and fractured rock systems. He is the chief developer of LBNL’s multi-phase non-isothermal reactive flow and chemical transport simulator TOUGHREACT. The program is widely used nationally and internationally for CO2 geological sequestration, geothermal energy development, nuclear waste disposal, environmental remediation, and increasingly for petroleum applications. Tianfu has authored and co-authored about 150 peer-reviewed journal papers. His papers have been cited by other researchers more than 7000 times (SCI citation).
Introduction of the Lecture
Among several kinds of geological reservoirs (such as deep saline aquifer, depleted gas and oil reservoirs, and non-mining coal seams), the saline aquifer has become the preferred reservoir for CO2 geological storage (CGS) because of its large reserves and wide distribution (Guo et al., 2015; Zhang et al., 2015). Under the high temperature and pressure environment, CO2 injection is often accompanied by a series of complex geo-mechanical and geochemical processes (Li et al., 2016). CO2 injection will change pore fluid pressure, thus leading to changes in formation effective stress, and may cause rock matrix deformation or failure (Rutqvist et al., 2010). At the same time, CO2-induced chemical reactions may lead to mechanical weakening of rocks, thus affecting their mechanical stability (Rohmer et al., 2016). Meanwhile, mineral dissolution and precipitation, thermal and mechanical deformation of rock change the pore structure and porosity, thus affecting the flow path and rate of the fluid (Pawar and Guthrie, 2019; Wang et al., 2023). These processs jointly determine the fate of injected supercritical CO2 in saline aquifers, and may also lead to a series of engineering or environmental geological problems, such as surface uplift, fracture of caprock, and CO2 leakage, etc. (Pruess, 2008; Rutqvist et al., 2010). To gain a better understanding and accurate prediction of the long-term fate of injected CO2 in saline aquifers, it is necessary to carry out simulation studies on the evolution of the temperature, pressure, chemical and 2 stress fields, as well as the interaction between these fields in the underground media (i.e., THCM coupled simulation).