fortheSeparationofMulticomponentMixtures

Control properties of thermally coupled distillation arrangements for the separation of multicomponent mixtures were compared to those of conventional distillation sequences. Seven thermally coupled schemes were investigated. The preliminary steady – state design of complex schemes was obtained by starting from a conventional distillation sequences and then optimizing for minimum energy consumption (energy-efficient designs). The dynamic behavior of the sequences considered were obtained by using the singular value decomposition technique at zero frequency. It was found that, in general, the complex schemes present theoretical control properties similar or better to those of conventional distillation sequences. This result is significant because it lets one establish that the energy savings predicted for thermally coupled distillation sequences are achieved without introducing additional control problems. Key words: Thermally coupled distillation sequences, energy requirements, dynamic properties, multicomponent mixture