The theoretical control properties and dynamic responses under closed-loop operation of thermally coupleddistillation sequences for the separation of five-component mixtures of hydrocarbons were compared to thoseof conventional distillation sequences. Seven thermally coupled arrangements were investigated: five thermallycoupled distillation sequences with three recycles and two thermally coupled distillation schemes with tworecycles. The preliminary steady-state design of complex schemes was obtained by starting from a conventionaldistillation sequences and then optimizing for minimum energy consumption [Calzon-McConville, C. J.;Rosales-Zamora, M. B.; Segovia-Hern
ndez, J. G.; Hern
ndez, S.; Rico-Ram&
iacute;rez, V. Design and Optimizationof Thermally Coupled Distillation Schemes for the Separation of Multicomponent Mixtures.
Ind. Eng. Chem.Res. 2006,
45, 724]. The control properties of the sequences considered were obtained by using the singularvalue decomposition technique at zero frequency. It was found that, in general, the coupled schemes presenttheoretical control properties similar to or better than those of conventional distillation sequences. This resultwas corroborated by using rigorous closed-loop dynamic simulations. As a result, one can conclude that theenergy savings predicted for thermally coupled distillation sequences are achieved without introducing additionalcontrol problems if we assume constant pressure drops in columns.