Considerations for the dew point calculation in rich natural gas

• C7+ fraction splitting is recommended for rich natural gases equilibrium.
• Van der Waals forms of EoS are fairly accurate for HCDP.
• Gas condensate dew point is fairly predicted by typical correlations.
• Temperature dependant parameters should be adjusted for extensive rich gas databases.
• Simple mixing rules are accurate for HCDP.

Hydrocarbon Dew Point (HCDP) in natural gas processing is a key quality parameter and a critical consideration for pipeline operations. In the present paper, a comparison between equations of state approaches is presented by estimating HCDP in rich natural gas using different approaches, i.e. PR, SRK or GERG-2004 EoS. Further, a parameter comparison is performed discussing the impact on the accuracy of estimating HCDP in natural gas using the selected approaches. The following parameters are compared: binary interaction coefficients, C7+ characterization methods, critical properties for single-carbon number groups and mixing rules. A set of considerations is presented in order to guide users to choose the most accurate right method for calculating HCDP in natural gas.