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Gas Compressibility (Z-Factor)

PRO

Calculate Z-factor, gas density, formation volume factor, and viscosity. Z vs Pressure chart.

Gas Properties

Pressure (psia)

Temperature (°F)

Gas Specific Gravity (air=1)

H2S Mole Fraction (%)

CO2 Mole Fraction (%)

N2 Mole Fraction (%)

Z-Factor

Gas Density

Bg (gas FVF)

Gas Viscosity

Ppc (psia)

Tpc (°R)

Ppr

Tpr

How this was calculated

Pseudocritical properties: Sutton (1985) correlations with Wichert-Aziz (1972) correction for H2S and CO2.

Z-factor: Dranchuk-Abou-Kassem (1975) correlation - 11-constant equation fit to Standing-Katz chart data.

Gas density: rho = P*M/(Z*R*T) where M = 28.97*SG, R = 10.73 psia-ft3/(lbmol-R).

Gas FVF: Bg = 0.02829*Z*T/P (rcf/scf).

Viscosity: Lee-Gonzalez-Eakin (1966) correlation.

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