Interstage cooling reactor staging with

Reactor staging with interstage cooling. Similar to P8-13b. but shorter because X, versu.s T is given. [3rd Ed, P8-1 Sg]... 

The next simplest reactor type is a sequence of adiabatic reactors with interstage heating or cooling between reactor stages. We can thus make simple reactors with no provision for heat transfer and do the heat management in heat exchangers outside the reactors. 

A contour plot given in Figure 5.17 shows how TAC varies in a two-stage adiabatic reactor system with interstage cooling. The reactant ratio yRA/yRB is fixed at unity in this figure, so there are two design optimization variables, the inlet temperatures of the two reactors 7) and T2-... 

Figure 6.2 Three-stage adiabatic reactors with interstage cooling system.

TABLE 6.4 Controller Tuning for Three-Stage Adiabatic Reactor System with Interstage Cooling ... 

Openloop Response The openloop response of a three-stage adiabatic reactor system with interstage cooling to a 20% increase in recycle flow FR is shown in Figure 6.14. The reactor inlet and exit temperatures of each reactor are shown. This system with heat feedback and large reactor gains is openloop unstable. 

Figure 27. Methanol synthesis under autothermal operation (reverse flow reactor) A. B) Temperature and conversion pr< period C) Reaction path for reverse flow operation and for a two-stage adiabatic reactor with interstage cooling [46]...

There are two classes of reaction systems for which the single-stage adiabatic reactor is incapable of satisfying the demands that can be placed upon reactant conversion and selectivity. The first class is reversible exothermic reactions. Multiple stages with interstage cooling are required for these reactions to achieve an acceptable conversion level with a reasonable reactor volume. 

In adiabatic reactors, a common situation is one in which a heated reactant is passed over a bed of catalyst placed inside a heat-insulated reactor or a sequence of such reactors (or stages) with interstage cooling. Then the problem is to optimize the number and size of stages for maximum profit. The design methodology is thus different from that for the tubular fixed-bed reactor. 

This arrangement is similar to that of the interstage cooling structure provided earlier. However in this scenario, a portion of the feed is bypassed and mixed with reactor product after each reaction stage, and there is no need to use dedicated cooling equipment, which lowers the costs of operation. The mixture temperature must lie at an intermediate value between the feed and product temperatures. It follows that an expression for how reactor feed temperatures vary with mixing is thus necessary. 

Figure 8.3 Muitipie-stage reactor with interstage cooling.

The outlet stream from the primary compressor is mixed with the high-pressure recycle gas stream and compressed in the hypercompressor up to a final pressure of approximately 1200-2500 bar for autoclaves and 2000-3300 bar for tubular reactors. The hypercompressor is a two-stage reciprocating compressor with interstage cooling. 

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