Impacts of equations of state (EOS) and impurities on the volume calculation of CO 2 mixtures in the applications of CO 2 capture and storage (CCS) processes

Abstract

Volume property is the necessary thermodynamic property in the design and operation of the CO 2 capture and storage system (CCS). Because of their simple structures, cubic equations of state (EOS) are preferable to be applied in predicting volumes for engineering applications. This paper evaluates the reliabilities of seven cubic EOS, including PR, PT, RK, SRK, MPR, MSRK and ISRK for predicting volumes of binary CO 2 mixtures containing CH 4, H 2S, SO 2, Ar and N 2, based on the comparisons with the collected experimental data. Results show that for calculations on the volume properties of binary CO 2 mixtures, PR and PT are generally superior to others for all of the studied mixtures. In addition, it was found that the binary interaction parameter has clear effects on the calculating accuracy of an EOS in the volume calculations of CO 2 mixtures. In order to improve the accuracy, k ij was calibrated for all of the EOS regarding the gas and liquid phases of all the studied binary CO 2 mixtures, respectively.