An improved correlation for densities of compressed liquids and liquid mixtures

The Tait equation has been extended and generalized to permit the calculation of densities of compressed liquids and their mixtures to a pressure of 68,950 kPa (10,000 psia) using only critical temperature, critical pressure, Soave‐Redlich‐Kwong acentric factor, saturation pressure, and saturated volume for a pure liquid or the corresponding mixture parameters for a liquid mixture. This correlation, together with the correlation developed by Hankinson and Thomson (1979) for saturated liquid densities, comprise COSTALD (COrresponding STAtes Liquid Density), an integrated method for estimating densities of nonpolar and slightly polar liquids and mixtures. The new correlation gave 0.446 average absolute percent error for 6,338 data points for nonpolar liquids, 2.57% error for 1352 data points for polar and quantum liquids, 0.369% error for 319 data points for LNG/LPG mixtures, and 1.61% error for all mixtures tested.