Automatic synthesis of distillation processes for the separation of homogeneous azeotropic multicomponent systems
The synthesis of distillation processes for azeotropic systems is a complex task for which commercial simulation software mainly offers a graphical analysis of residue curve maps, limited to ternary (sub)systems, or an iterative evaluation based on tedious simulation studies. The current work features a novel algorithmic approach that aims at an automatic synthesis of distillation-based separation processes for azeotropic mixtures. Unlike other methods available in the literature, the feasibility of separation in a simple column is evaluated for both limiting operating conditions, total reflux and reversible distillation. Furthermore, the method integrates a pinch-based shortcut method to verify split feasibility and estimate the minimum energy demand. Thus, feasible process variants are generated solely based on a thermodynamic model of the multicomponent mixture, incorporating suitable recycle streams, and pressure variation, thus enabling a computationally efficient and reliable process synthesis. The capabilities and efficiency of the proposed method are illustrated for different multicomponent azeotropic mixtures.