ABSTRACT
ABST R AC T Shortcut methods are a valuable tool in the early stages of chemical process design, where numerous owsheet alternatives need to be evaluated to determine the most energy-efcient, feasible owsheet. Various shortcut methods based on tray-to-tray calculation and pinch point analysis for the inspection of feasibility and the determination of the minimum energy demand for homogeneous azeotropic distillation have been published in the literature. For multicomponent heteroazeotropic distillation, however, no generally applicable shortcut methods have been presented so far. Based on the existing shortcut methods for homogeneous distillation, a shortcut method for heteroazeotropic distillation, the feed pinch method (FPM) is proposed in this work. The FPM is based on rigorous thermodynamics, applicable to heterogeneous azeotropic mixtures of any number of components and can be automated. The new method is illustrated by several
CONTENTS
Introduction ....................................................................................................... 1036 Review of Existing Shortcut Methods ............................................................ 1036 Application to Heterogeneous Mixtures ....................................................... 1039 Feed Pinch Method for Heteroazeotropic Distillation ................................. 1042 Quaternary Heterogeneous System Water, n-Butyl Acetate, n-Butanol, Acetic Acid ...................................................................................... 1047 Quaternary Heterogeneous System Acetone, Water, Butanol, Ethanol .... 1050 Conclusion ......................................................................................................... 1051 Acknowledgments ............................................................................................ 1051 References ........................................................................................................... 1052
examples of ternary as well as quaternary heteroazeotropic separations, for which feasibility and minimum energy demand is determined with paramount robustness and efciency.
