Volume 56

Measurement and Modeling of CO2 Solubility Under Offshore CCUS Conditions Shuai ZHANG, Yi ZHANG, Yu LIU, Yongchen SONG

Abstract

The solubility of CO2 under ocean storage conditions affects the dissolution rate and dissolution amount of CO2 in seawater, and then affects the final storage amount. In this study, the solubility of CO2 in actual seawater was studied by a combination of experiments and models. Firstly, based on the literature data, the model of carbon dioxide solubility in pure water was constructed, and the AAD was 2.2%. Then, a solubility measurement system based on Raman spectrometer was built, and the quantitative relationship between peak intensity ratio and solubility S=HR/0.20225 was established by solubility method, and the solubility of CO2 in the actual seawater in the range of 276.15-286.65 K and 2-20 MPa was further measured by using this quantitative relationship, and the measurement results showed that the sensitivity of CO2 solubility in seawater to seawater depth was significantly reduced after the storage depth of 400m. Finally, the obtained experimental data was coupled with the model, and the AAD was 2.8%.

Keywords CCUS, solubility, thermodynamic model, Raman spectroscopy