Número Óptimo de Etapas de Equilibrio en un Proceso de Destilación Extractiva Etanol-Agua-Etilenglicol

This paper deals with the optimal design of a production process of anhydrous ethanol by extractive distillation using ethylene glycol as a solvent. The process has two distillation towers, an extractive where ethanol is separated and a recovery from which the solvent is recycled. A mixed integer nonlinear programing (MINLP) model based on a superstructure that embeds all the attractive and technologically feasible configurations is proposed. The proposed model allows to determine the optimal number of equilibrium stages, the feed location and optimal operating conditions of both towers simultaneously. The model is implemented in GAMS, and the results were successfully validated with those thrown by commercial simulators (HYSYS). A case of application is presented to show the ability of the model and discuss the results.