Synthesis of Distillation Based Separati

This tutorial paper is a review of recent advances in the synthesis of ideal and nonideal distillation-based separation systems. We start by showing that the space of alternative separation processes is enormous. We discuss simple methods to classify a mixture either as nearly ideal or as nonideal, in which case it displays azeotropic and possibly liquid/liquid behavior. For nearly ideal mixtures, insights based on marginal vapor flows permit the development of a simple screening criterion computed using only relative volatilities and component feed flowrates to find the better column sequences from among the many possible. This criterion explains several of the traditional heuristics. We also examine how one can invent alternative structures to separate non-ideal mixtures and present illustrative approaches with three examples. Overall, our analysis provides a comprehensive understanding of the methodologies involved in the synthesis of separation systems, emphasizing both theoretical insights and practical implications.