Modelling CO2-water thermodynamics using SPUNG equation of state (EOS) concept with various reference fluids

Abstract

Due to the continuous increase of CO2 emission to environment, the Carbon Capture and Storage (CCS) processes gained a very high importance in the last decades. One common CO2 impurity during various CCS processes is water. Therefore, the calculation of CO–water thermodynamic properties is a vital issue. This work preliminary investigates the accuracy of the extended corresponding states equation of state SPUNG using various reference fluids for the density and vapour liquid equilibrium (VLE) calculations of the CO2 - water system. The evaluation is done by comparing the numerical prediction with experimental data. The study is conducted at different mixture concentrations, and covering a broad range of conditions. The study is conducted using N2, O2, C1, C2, C3, and C4 as reference fluids. The results show an impact on density prediction. On the other hand, the VLE calculations exhibited very low sensitivity to varying reference fluids.