Optimal Synthesis of Distillation Systems for Bioethanol Separation. Part 1: Extractive Distillation with Simple Columns

The article presents an analysis between different possible sequences for the separation of bioethanol from a typical fermentor's stream. The preconcentrator column, necessary to approach the azeotropic composition was included as a fundamental part of the sequences. Starting from a recently proposed four-column configuration in the literature, a full set of alternatives was predicted and explored in detail. Different combinations of partial and total condensers were considered so as to possibly reduce the amount of equipment. It was proved that among all the simple configurations generated, two sequences with three columns are able to consistently reduce the energy demand and the capital costs. The results obtained represent the first step for the further generation of complex configuration sequences.