Reactive distillation column design for controllability: A case study

The temperature inferential control of two alternate designs of the double feed ideal reactive distillation (RD) column is studied. Controlling the most sensitive tray temperature in the first design causes the control system to succumb to non-linear dynamic phenomena for large throughput changes. For the two control structures studied, the second design handles larger throughput changes. A bifurcation study implicates input multiplicity for the observed non-linear dynamic phenomena in the two designs. For good controllability, the need for designing a column with high tray temperature sensitivity and mitigating input multiplicity is highlighted.