Non-hydrocarbon impurity pseudocritical properties
Non-hydrocarbon impurity pseudocritical properties: A3.4. Pseudocritical Pressure and Temperature of Non-Hydrocarbon Impurities Carr The Carr correlation allows correction of…
A3.4. Pseudocritical Pressure and Temperature of Non-Hydrocarbon Impurities#
Carr
The Carr correlation allows correction of the pseudocritical pressure and temperature of natural gas in the presence of non-hydrocarbon impurities. The method is especially useful for fields with high concentrations of acid gases, where standard methods produce significant errors.
Recommended applicability range:
- Gas specific gravity (air = 1): 0.55 – 1.2
- CO₂ content: < 20%
- H₂S content: < 25%
- N₂ content: < 5%
Piper & McCain
The Piper & McCain correlation is an advanced method for determining pseudocritical properties of gas-condensate mixtures containing non-hydrocarbon components. It was developed based on an extensive database from North Sea fields. The model provides high accuracy for complex multicomponent systems.
Recommended applicability range:
- Gas specific gravity (air = 1): 0.55 – 1.2
- CO₂ content: < 20%
- H₂S content: < 30%
- N₂ content: < 10%
Wichert & Aziz
The Wichert & Aziz correlation is a fundamental method for adjusting pseudocritical properties of natural gases with elevated levels of acid gases. The method accounts for the non-ideal behavior of such mixtures and ensures accuracy in the calculation of the gas compressibility factor. It is not applicable to gases with a high content of heavy hydrocarbons (C₇⁺ > 5%).
Recommended applicability range:
- Gas specific gravity (air = 1): 0.55 – 1.0
- CO₂ content: < 40%
- H₂S content: < 40%