Flash Distillation of a Benzene, Toluene, p-Xylene Mixture
Prepared by H. Binous, M. Al-Harthi, and B. G. Higgins
Consider a ternary mixture of benzene, toluene, and p-xylene (BTX). For this ideal system, vapor-liquid equilibrium data can be computed using Raoult's law, Pyi = Pisatxi, where Pisat is the vapor pressure of component i given by Antoine's equation, P is the total pressure, and xi and yi are the liquid and vapor phase mole fraction of component i. You can select a feed composition by dragging the locator in the ternary triangular diagram (i.e. inside the light blue region) and you can vary the values of P (expressed in mmHg) and T (expressed in °C). This Demonstration computes the vapor fraction φ of the feed and the composition of the liquid and vapor streams leaving the isothermal flash drum. Only when Tbubble < T < Tdew  will the feed be a two-phase mixture such that 0 < φ < 1.

Download the CDF file to view the simulation using the free Wolfram CDF player.