CORDEIRO, G. M.; http://lattes.cnpq.br/2060711070034296; CORDEIRO, Gardênia Marinho.
Resumo:
The process intensification through dividing wall column (DWC) and thermal
coupling of two columns (TCS) are noted in the literature consulted as one of the most
promising alternatives to reduce energy consumption of the distillation process. Specifically
by extractive distillation process, the use of these settings is still questionable and
nonconsensual as to its potential to reduce total costs. In this work, in order to assess
accurately the feasibility of TCS, three approaches of energy reduction (optimization, thermal
and thermal coupling integration) are analysed and concatenated in order to reduce the total
annual cost (TAC) and specific energy consumption (SEC). The use of an optimization
procedure based on the solvent content, with guaranteed global optimal solution was effective
in reducing these costs, since presented smaller results (SEC and TAC) compared to all
studies of the literature examined. The inclusion of a thermal integration to preheat the
azeotrope with the recycle proved to be competitive with the use of thermal coupling. To
extend the assessment in DWC, considering the equivalence in terms of stage of equilibrium
with TCS, proposed a systematic strategy for obtaining a DWC configuration optimized in
terms of design and operational. A strict comparison between DWC and CS (optimized too)
was performed and showed the influence of the number of stages of the columns in the
performance of these configurations. In relation to energy costs, all the DWC's were
favorable, however, the percentage of reduction of thermal load depends on which CS took as
a reference. The best TAC’s results were obtained for columns with distinctive number of
stages on each side of the wall, however, these columns do not have overcome the
conventional systems optimized. Economically, the decision about the type of configuration
more viable for an industrial application can be taken as the basis of the presented strategies,
noting the trade-off between the ability of energy reduction of DWC's and the costs of the
process of the optimized configurations.