Types and Examples of Reactors

The reference mixture has H2/N2= 3 and contains 12.7% inert other ratios had slightly different effectiveness. The particle diameters are 6-10 mm. Some calculations from this equation at 225 atm are  

For oxidation of sulfiir dioxide, measurements of effectiveness were made by. Kadlec, Pour, and Regner [Coll. Czech. Chem. Commun. 33, 2388, 2526 (1968)1 whose data are shown following. They are at atmospheric pressure. The initial content of SO, and the conversion have little effect on the result. Both increase in size of granule and temperature lower the effectiveness, although the effect of temperature is somewhat erratic. 

The rate equations of both these processes are quite complex, and there is little likelihood that the effectiveness could be deduced mathematically from fundamental data as functions of temperature, pressure, conversion, and composition, which is the kind of information needed for practical purposes. Perhaps the only estimate that can be made safely is that, in the particle size range below 1 mm or so, the effectiveness probably is unity. The penetration of small pores by liquids is slight so that the catalysts used in hquid slurry systems are of the low specihc surface type or even nonporous. 

Almost every kind of holding or contacting equipment has been used as a chemical reactor at some time, from mixing nozzles and centrifugal pumps to the most elaborate towers and tube assembhes. This section is devoted to the general characteristics of the main kinds of reactors, and also provides a gallery of selected examples of working reactors. 

When heterogeneous mixtures are involved, the conversion rate oflen is limited by the rate of interphase mass transfer, so that a large interfacial surface is desirable. Thus, solid reactants or 

Batch processing is used primarily when the reaction time is long or the required daily production is small. The same batch equipment often is used to make a variety of products at different times. Otherwise, it is not possible to generalize as to the economical transition point from batch to continuous operation. One or more batch reactors together with appropriate surge tanks may be used to simulate continuous operation on a daily or longer basis. 

CODE j jCommonly used ( Rarelv used 1 Not feasible 

REACTOR TYPE Tank Tank Tank battery Tubular  

Power input per unit volume and impeller tip speeds are often used measures of the intensity of stirring, assuming correct proportions of the vessel and proper baffling. Appropriate ranges for some reaction conditions are as tabulated  

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