Automatic synthesis of distillation processes for the separation of azeotropic multi-component 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 for ternary (sub)systems or an iterative evaluation based on tedious simulation studies. The current work presents a novel algorithmic approach that aims at an automatic synthesis of distillation-based separation processes for azeotropic systems. Building only on a thermodynamic model of the multi-component mixture, split feasibility at both limiting operating conditions of total reflux and reversible distillation are considered. Possible process variants including the integration of suitable recycle streams are automatically generated and stored in a tree structure and the incorporation of an efficient pinch-based shortcut method provides initial estimates of the required energy demand of the generated process variants. The application of the proposed method is illustrated for the separation of a four and five component azeotropic mixture, which allow comparison with previous publications.