Design and control analysis of thermally coupled configurations for quaternary distillations

In this work we developed a comparative study of the energy consumption, thermodynamic efficiency, total annual costs and control properties (using the singular value decomposition technique in the frequency domain) of five thermally coupled distillation sequences for the separations of quaternary mixtures. The results show that the structure has different effects on energy consumption, capital costs and dynamic performance. These results are significant because they let us establish that coupled schemes not only require lower energy demands and have better thermodynamic efficiencies than the conventional distillation sequences but also present theoretical control properties similar or better to those of the conventional distillation sequences used in the preliminary design of the thermally coupled distillation sequences.