Insights into Dynamic Process Intensification for Reactive Distillation Columns

In Dynamic Process Intensification (DPI) a more economic operation compared to a steady state is achieved by blending the product of multiple operating states. In our study we present a systematic approach for the determination of these operating states for reactive distillation processes. Furthermore a closed loop control scheme is presented and validated with a dynamic simulation. As DPI has already been shown to be feasible for the reactive distillation of dimethyl ether from methanol, it was used as the first case study. The combined reboiler and condenser duty is reduced by 4.2% compared to the optimal operating point without DPI. The time average methanol conversion and the product purity remain unchanged compared to the optimal steady state. It is demonstrated that the proposed closed loop control scheme ensures stable operation in the event of disturbances up to 10% to the column feed flow, while maintaining the characteristics of DPI. The reactive distillation of methyl acetate from methanol and acetic acid is used as a second case study, since extensive literature data are available for such an analysis. It is demonstrated that DPI is infeasible for this process and the column should be operated in the optimal steady state. [Display omitted] •Periodic operation of reactive distillation columns can increase energy efficiency.•Average product flow and purity can remain virtually unchanged.•Output multiplicity creates conditions suitable for periodic operation.•Short cycling periods make periodic operation infeasible.•A proposed control scheme can reject feed flow disturbances of up to 10%.