PVTx Modeling of CO2 Pipeline at Depressurization Conditions Using SPUNG Equation of State (EoS) with a Comparison to SRK

Abstract The proper modeling of CO 2 depressurization is very important for the design for safety of a pipeline. One key element of the modeling process is the thermodynamics and transport properties modeling. In this work, an analysis of the error in thermodynamics for modeling CO 2 at depressurization conditions was conducted. For the study presented here, the sophisticated equation of state (EoS) SPUNG was used. The results were compared to an EoS of a different level of complexity and, consequently, accuracy. This EoS is the cubic equation Soave–Redlich–Kwong (SRK) with van der Waal's mixing rules. The results show the significance of the thermodynamics modeling at a set of pressures, temperatures and compositions PVTx over time steps complying with two sets of experimental data.

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