Optimal Thermodynamic Approximation to Reversible Distillation by Means of Interheaters and Intercoolers

The purpose of this paper is to deal with the problem of heat and power integration on one side and the problem of minimizing heat exchange areas on the other side, in both conventional and nonconventional distillation columns. We consider the limiting case of columns operating at minimum reflux. The appropriate objective functions that one must consider are the entropy production rate and the total heat exchange area, respectively. This is done by means of optimal placement of a given number of interheaters (IHs) and intercoolers (ICs) in stripping and rectifying sections, respectively. To solve these problems, an appropriate thermodynamic model for both conventional and nonconventional distillative columns is formally presented. This model allows us to formulate an optimization problem involving thermodynamically reversible profiles in stripping and rectifying sections of the columns. Our approach differs from others previously reported in that multiple reversible profiles were identified for each secti...