Shortcut methods are valuable tools in the early stages of chemical process design, where numerous flowsheet alternatives need to be evaluated to determine the most energy-efficient, feasible flows heet. Various shortcut methods based on tray-to-tray calculation and pinch point analysis for the inspection of feasibility and the determination of t he minimum energy demand (MED) for homogeneous nonideal distillation have been published in the literature. Rec ently, Kraemer et al. 1 presented the

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... eed pinch method (FPM) for heterogeneous azeotropic mixtures of any number of components. While the FPM returns an accurate repres entation of the ME D, it still requires tray-to-tray calculations for one column section and it can only be applied to separations with a feed pinch, i.e. usually direct or indirect splits. In this work, we propos e the feed angle method (FAM) which resolves both of these issues as it does not rely on numerous tray-to-tray calculations and can be applied to any kind of sharp split. The FAM is illustrated by t ernary and quaternary heteroazeotropic separations with direct, indirect and intermediate splits.