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-; CODEN: ACPCA
• Journal Information: American Chemical Society, Division of Petroleum Chemistry, Preprints; (United States), Vol. 35:4; Conference: 200. American Chemical Society (ACS) national meeting, Washington, DC (United States), 26-31 Aug 1990; ISSN 0569-3799
• Country of Publication: United States
• Language: English

Related Subjects

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