Improved temperature dependence for the attractive term in the Peng-Robinson equation of state

Conference · Wed Aug 01 00:00:00 EDT 1990 · American Chemical Society, Division of Petroleum Chemistry, Preprints; (United States)

OSTI ID:6969009

Khalil, Y F; Anderson, T F ^[1]; Lovland, J ^[2]

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1. Univ. of Connecticut, Storrs (United States)
2. Norwegian Inst. of Tech., Trondheim (Norway)

Numerous equations of state (EOS), ranging from simple expressions with two parameters to more complicated equations containing many parameters, have been presented in the literature. Complex equations, such as those of Benedict-Webb-Rubin and Strobridge, are desirable when very accurate representation of the P-V-T data is needed, but they often impose an excessive calculational burden when used for phase-equilibrium calculations in mixtures. Simpler equations of state, such as those cubic in volume, are much easier to apply to phase-equilibrium calculations. Examples of these equations include the Redlich-Kwong EOS, the Soave-Redlich-Kwong EOS, the Peng-Robinson EOS, and the Usdin-McAuliffe EOS. Although semi-empirical, these relatively simple equations are extensively used and are quite adequate for many thermodynamic property calculations of both pure compounds and mixtures. One of the most important applications of these cubic equations is the calculation of phase equilibria. To correlate and predict equilibrium conditions, the pure-component vapor pressure must be accurately represented. A new temperature function for the attractive parameter, {alpha}, of the Peng-Robinson equation of state has been proposed. This form is simple and retains the calculational ease of the original Peng-Robinson equation. The proposed temperature form as well as six published temperature dependence forms for the attractive parameter, {alpha}, were individually introduced into the Peng-Robinson equation; the resulting equations were then compared to determine their ability to accurately reproduce existing vapor pressure data. Reliable sources of experimental vapor pressure data for thirty pure components formed the data base for this work. The pure component library included aliphatics, aromatics, alcohols, water, and gases such as helium, carbon monoxide, carbon dioxide, chlorine, and ammonia.

• OSTI ID: 6969009
• Report Number(s): CONF-900802--
• Journal Information: American Chemical Society, Division of Petroleum Chemistry, Preprints; (United States), Journal Name: American Chemical Society, Division of Petroleum Chemistry, Preprints; (United States) Vol. 35:4; ISSN 0569-3799; ISSN ACPCA
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
023000* -- Petroleum-- Properties & Composition
ALCOHOLS
AMMONIA
AROMATICS
CALCULATION METHODS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
CHLORINE
ELEMENTS
ENERGY SOURCES
EQUATIONS
EQUATIONS OF STATE
EQUILIBRIUM
FLUIDS
FOSSIL FUELS
FUELS
GASES
HALOGENS
HELIUM
HYDRIDES
HYDROCARBONS
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
MATHEMATICAL MODELS
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NONMETALS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PETROLEUM
PHASE STUDIES
PHYSICAL PROPERTIES
POLAR COMPOUNDS
RARE GASES
TEMPERATURE MEASUREMENT
THERMODYNAMIC PROPERTIES
VAPOR PRESSURE
WATER