Factors of Progress Technological Innovations and Increased Fundamental Insight

Among the many technological innovations of recent years are the following 

The use of reactor models as a basis for design, associated with the ever-increasing possibilities of computers. This is an aspect that will be dealt with extensively further in this chapter. To place this aspect in the right perspective, earlier stages of design in which decisions are taken on the basis of sound judgment and semi-quantitative considerations will be discussed first. 

3 Factors Involved in the Preliminary Design of Fixed Bed Reactors  

When a reactor has to be scaled up from its bench scale version, a certain number of questions arise as to its ultimate type and operation. In general, several alternatives are possible. These may be retained up to a certain degree of progress of the project, but a choice will have to be made in as early a stage as possible, on the basis of qualitative or semiquantitative considerations, before considerable effort is invested into the detailed design. 

The first and most elementary type of reactor to be considered is the adiabatic. In this case, the reactor is simply a vessel of relatively large diameter. Such a simple solution is not always applicable, however. Indeed, if the reaction is very endothermic, the temperature drop may be such as to extinguish the reaction before the desired conversion is attained—this would be the case with catalytic reforming of naphtha or with ethylbenzene dehydrogenation into styrene. Strongly exothermic reactions lead to a temperature rise that may be prohibitive for several reasons for its unfavorable influence on the equilibrium conversion, as in ammonia, methanol, and SO3 synthesis, or on the selectivity, as in maleic anhydride or 

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Factors of Progress Technological Innovations and Increased Fundamental Insight... 

FACTORS OF PROGRESS TECHNOLOGICAL INNOVATIONS AND INCREASED FUNDAMENTAL INSIGHT... 

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