Consider a steady-state ternary mixture of benzene (

), toluene (

), and

-xylene (

) at

. This mixture, with a thermal quality equal to 1.0 (i.e. saturated liquid), is fed to a 19-stage column with a total condenser and partial reboiler. The feed is at stage 10. The feed flow rate is set to

. You can set the values of the reflux and reboil ratios (

and

, respectively). This Demonstration computes the temperature and composition profiles using a rigorous approach, which includes both the energy and mass balances. The blue, magenta, and brown curves, shown in the composition profile, correspond to benzene, toluene, and

-xylene compositions, respectively. For

and

, the results found in the present Demonstration show good agreement with those given by HYSYS (
http://www.aspentech.com/hysys/). HYSYS data is shown with colored dots. The calculation of enthalpies can be improved by taking temperature-dependent heat capacity, for example.