Optimal adiabatic bed reactors

Optimal adiabatic bed reactors for sulfur dioxide with cold shot cooling (with K.-Y. Lee). Ind. Eng. Chem. Proc. Des.-Dev. 2, 300-306 (1963). 

J. P. Malenge and J. Villermaux, Optimal Adiabatic Bed Reactor with Cold Shot Cooling, Ind. Eng. Chem. Process Design and Develop., 6, 535 (1967). 

Case Study Optimal Adiabatic Bed Reactors for SuHiir Dioxide with Cold Shot Cooling... 

Optimal adiabatic bed reactor with cold shot cooling. Industrial and Engineering Chemistry Process Design and Development,... 

Nonisothermal reactors with adiabatic beds. Optimization of the temperature profile described above assumes that heat can be added or removed wherever required and at whatever rate required so that the optimal temperature profile can be achieved. A superstructure can be set up to examine design options involving adiabatic reaction sections. Figure 7.12 shows a superstructure for a reactor with adiabatic sections912 that allows heat to be transferred indirectly or directly through intermediate feed injection. 

Leitenberger s work (1939) is concerned with the oxidation of sulfur dioxide in adiabatic beds and tubular reactors. Using the Boresskow-Slinko kinetic equation he calculated the optimal tem-6... 

The optimal catalyst distribution problem was studied in an adiabatic reactor (Ogunye and Ray, 197la,b). The optimal initial distribution of catalyst activity along the axis of a tubular fixed-bed reactor was examined for a class of reactivation-deactivation problems by Gryaert and Crowe (1976). A general set of simultaneous reactions was considered, quasi steady state approximation was used, and the decay of the catalyst expressed as a function of temperature, concentration and catalyst activity. The influence of various initial catalyst activity distributions upon the reactor performance was also considered. 

Packed-bed reactors can be adiabatic, and Equation 9.3 takes a particularly simple form with no radial gradients in temperature or composition arising when the feed is premixed. If the fluid is uniform in the radial direction when it enters the reactor, it remains uniform. Thus adiabatic packed beds are normally modeled as PERs. This assumption may be overly optimistic in terms of yields and selectivities. The axial dispersion model in Section 9.2 adds a correction term to avoid undue optimism. Unmixed feed streams can also be treated provided the reactants enter the reactor in a manner that preserves radial symmetry. 

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. 

Figure 8.24. Left schematic diagram of an adiabatical three-bed, indirectly cooled reactor with two heat exchangers. Right a diagram showing the equilibrium curve to the upper right, the optimal operating line and the operation line for the reactor are to the left. [Adapted from C.J.H. Jacobsen, S. Dahl, A. Boisen, B.S. Clausen,...

Studies in optimization-I The optimum design of adiabatic reactors with several beds. Chem. Eng. Sci., 12, 243-252 (1960). 

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