[H-SC06] CCUS (Carbon Dioxide Capture, Utilization, and Storage) for Climate Mitigation

[HSC06-01] Temperature Effect on Interfacial Tension of CO₂-Water Studied by Molecular Dynamics Simulation

*Masashige Shiga¹, Tetsuya Morishita^2,3, Masao Sorai¹ (1.CO2 geological storage research group, National Institute of Advanced Industrial Science and Technology, 2.Research Center for Computational Design of Advanced Functional Materials (CD-FMat), National Institute of Advanced Industrial Science and Technology, 3.Mathematics for Advanced Materials Open Innovation Laboratory (MathAM-OIL), National Institute of Advanced Industrial Science and Technology (AIST), c/o AIMR, Tohoku University)

Keywords:CO2 geological storage, Geothermal energy resources, Interfacial tension, Molecular dynamics simulation

In order to significantly reduce the amount of CO₂ emitted into the atmosphere and to achieve efficient resource development, research on CCUS (Carbon Capture, Storage, and Utilization) has been actively conducted for several decades. In recent years, high-temperature reservoirs have been considered for CO₂ injection. This is aimed at the development of unconventional geothermal resources and CO₂ deposits.
Since the value of CO₂-water interfacial tension is a fundamental property of fluid behavior in the CO₂-water-rock system, many studies have been reported. However, with the above technique, the temperature of the geothermal reservoir may rise to about 300°C, which is much higher than the typical conditions of CCUS. Measurements under such high-temperature conditions are not easy, and no experimental data have been reported in existing studies.
Therefore, in this study, we performed molecular dynamics simulations to estimate the interfacial tension up to 300 °C and investigated the detailed physical properties such as density and dynamics.