Prediction of the densities of Western Canadian heavy oils and their SARA fractions from the cubic equations of state

The accuracy of the Modified-Nasrifar-Moshfeghian (MNM) EOS in predicting the densities of heavy oils and their SARA fractions was evaluated. Each SARA fraction of four western Canadian heavy oils and bitumens was treated as a pseudo component. The equation of state was tuned with only one set of measured densities and were thereafter used for density predictions with no further fitting parameters. The results showed the MNM EOS without any volume correction could predict the SARA densities with accuracy similar to the SRK EOS with volume correction. The small error indicates that the tuned EOS could be used to accurately predict the densities of the SARA fractions of at least the Western Canadian heavy oils and bitumens.