화학공학소재연구정보센터
Fluid Phase Equilibria, Vol.224, No.2, 157-167, 2004
A simplified method for calculating saturated liquid densities
A simplification for the Nasrifar-Moshfeghian (NM) liquid density correlation has been developed. A replacement for the Mathias and Copeman temperature-dependent term with the original Soave-Redlich-Kwong equation of state (SRK EOS) temperature-dependent term has been done. This replacement has overcome the limitations in use for the original model due to the Mathias and Copeman vapor pressure-dependent parameters. The new correlation uses one characteristic parameter for each compound and suggests a value of zero for generalization purpose. The revised model has been tested for pure compounds liquid density prediction of different types including paraffins, cycloparaffins, olefins. diolefins, cyclic olefins, aromatics, ethers, liquefied inorganic gases and alcohols. The average absolute percent deviation for 76 compounds consisting of 2379 experimental data points was found to be 0.58%. The simplified method was then used to predict the saturated liquid density of multi-component systems. The average absolute percent deviation for 58 multi-component systems consisting of 978 experimental points was found to be 0.67%. Generalizing the correlation, by setting a value of zero for the characteristic parameter, gave average absolute percent deviation of 2.01% for the same pure compounds and 1.57% for the 58 multi-component systems. The accuracy of the simplified model has been compared with other correlations and equations of states. (C) 2004 Elsevier B.V. All rights reserved.