Info

Fig. 2.15 Equipment suitable for combining reaction and distillation (homogeneous catalysis)

Fig. 2.15 Equipment suitable for combining reaction and distillation (homogeneous catalysis)

Fig. 2.16 Principles of the choice of equipment (homogeneous catalysis)

number of stages necessary to influence the reaction in a desired way becomes so small and consequently the volume per stage becomes so large that a small reactor with a superimposed column or even a reactor with an evaporator can be used.

In the range of medium reaction velocities, mixed constructions are the ideal solution, for example special column trays with large holdup or reactor cascades with a column on the first stage only.

The resulting principles for the choice of equipment for homogeneous catalysis are presented in Fig. 2.16.

As mentioned earlier, heterogeneous catalysis can be treated in a similar manner: Additional, separate reaction volumes are necessary to retain the catalyst. These volumes can be arranged either within the equipment or in a side position [10], coupled by recycle systems. Fig. 2.17 lists the equipment alternatives for heterogeneous catalysis [11]. As in the case of homogeneous catalysis, principles for

Fig. 2.17 Equipment suitable for combining reaction and distillation (heterogeneous catalysis)

the choice of equipment may be formulated. Some, not all of the possibilities are shown in Fig. 2.18 [12-15].

After the choice of the equipment, which is in principle determined by the reaction velocity and the relative volatility the next step follows: the proper design of the chosen equipment under the special conditions of the process. Only if this step is done with care will the advantage of the proper choice of equipment, the optimum in energy consumption, be realized.

£ u

column with catalytic internals

short column with catalytic internals

evaporator with small reactor

column with catalytic internals with higher residence time

Was this article helpful?

0 0

Post a comment