A new correlation for vapor pressure prediction of natural gas mixture

Abstract

ABSTRACTIn this study, the Antoine equation of vapor pressure prediction for pure substances has been extended to predict vapor pressure values of a natural gas mixture at a temperature range of 125–230 K. The correlation was modified by applying the software MATLAB 8.2 R2013b (The MathWorks, Natick, MA). The developed correlation for multicomponent natural gas mixture is predictable with few input data of critical temperature, critical pressure, and the acentric factor. For the examined natural gas mixture, the predicted vapor pressures show comparable values with those obtained by applying well-known and accurate cubical equation of state (EOS) of Soave–Redlich–Kwong (SRK) and Peng–Robinson (PR) for the whole range of studied temperatures. From the results, an average absolute deviation of 1.735% for the developed correlation in this work was obtained from the actual results calculated experimentally, which is lower than that obtained by SRK EOS and close to results of PR EOS.