Investigation of Generalized Correlations and Prediction of Residual Enthalpy of Superheated Vapor for Pure Components and Mixtures

Prediction of accurate values of enthalpy (H) or enthalpy departure (H ) for gases is very important in process design calculations and other industrial applications.Experimental measurements of enthalpy or enthalpy departure for superheated vapor are not easy to perform. So in order to obtain accurate H or H  values,attention has been turned to calculate them using equations of state.In this study cubic equations of state were used to calculate enthalpy and enthalpy departure for pure superheated vapor, they were Soave-Redlich-Kwong equation of state,and Peng-Robinson equation of state. To overcome this problem effort were directed to modify Soave-Redlich-Kowng equation of state to predict enthalpy departure of pure components and to develop new correlation for mixture. A modification of Soave equation was made to improve its accuracy and this was done by introducing a new expression to calculate the m parameter in Soave equation. The new m parameter became a function of reduced temperature and reduced pressure as well as acentric factor as follows: