Dynamic Control Analysis of Various Side-Stream Quaternary Extractive Distillation Configurations

A thermally coupled distillation technology can bring energy-saving benefits, but it poses challenges to process control. This article explores dynamic control of different side-stream quaternary extractive distillation configurations. One the one hand, the open-loop controllability of these processes is analyzed in terms of various criteria by the control design interface technology of Aspen Plus Dynamics. On the other hand, their control structures are established and examined by introducing large feed flow and composition perturbations. The results show that the triple-side-stream distillation still performs the best state and input–output controllability in spite of the strongest nonlinearity, and is also well resistant to large feed perturbations using a simple control structure.