Effects of feed tray locations to the design of reactive distillation and its implication to control

The effects of feed locations to the design of reactive distillation are explored. In this work, ideal reactive distillation systems are used to illustrate the advantage of feed trays optimization in design and control. Process parameters such as relative volatilities between reactants, relative volatilities between products, column pressure, activation energies, and pre-exponential factors are varied to seek possible generalization. For all systems studied, the percentage of energy saving ranges from 6% to 47%, and this is obtained by simply rearranging the feed locations. Finally, the idea of optimal feed trays is extended to the operation/control of reactive distillation systems. First, steady-state analysis is carried out to find the optimal feed trays as measurable load variable varies. Then, a control structure is proposed to rearrange the feeds as the disturbance comes into the system. The results indicate that, again, substantial energy can be saved by feed rearrangement via the coordinated control structure.