We use a batch column with four theoretical plates to separate a binary mixture of water and methanol at 1 bar. Temperature and concentration profiles versus time are obtained for a reflux ratio equal to 10. In addition, the total moles in the still and distillate are plotted versus time. This demo shows how one can use ode15s to treat a complex system of 13 differential algebraic equations very easily. This problem is solve using Berkeley-Madonna Language in the reference indicated below. We get the same results as Ingham et al. (2000).

Reference: Example BUBBLE in page 559 by J. Ingham, I. J. Dunn, E. Heinzle and J. E. Prenosil, Chemical Engineering Dynamics, Wiley-VCH, Weinheim, Second Edition, 2000.

For a similar treatment using Mathematica 5.2, please visit:

http://library.wolfram.com/infocenter/MathSource/5929/

A Mathematica demonstration using version 6.0 is available at:

http://demonstrations.wolfram.com/StudyOfAFourStageBatchDistillationColumn/