Hybrid generalized modular/collocation framework for distillation column synthesis

Systematic and detailed methods are proposed for the synthesis of simple, heat integrated, and complex distillation column sequences for the separation of non-azeotropic mixtures based on formal superstructure optimization techniques. The Generalized Modular Framework (GMF) developed in previous works for the conceptual synthesis of the aforementioned sequencing problems is enhanced through the incorporation of principles of Collocation techniques for distillation order reduction. The proposed GMF/Collocation methods overcome structural complexities through systematically composed structural models and provide accurate and detailed guidelines for the optimal design and operation of the represented distillation sequences. The synthesis methods are applied for a number of sequencing case studies, generating substantial economic savings by finding systematically, accurately, and in a unified way the most cost efficient distillation column sequence. (c) 2005 American Institute of Chemical Engineers.