Variations in contacting pattern—semi-batch operation

Variations in Contacting Pattern — Semi-batch Operation 

A characteristic of semi-batch operation is that the concentration CB of the reactant added slowly, B in Fig. 1.2, is low throughout the course of the reaction. This may be an advantage if more than one reaction is possible, and if the desired reaction is favoured by a low value of CB. Thus, the semi-batch method may be chosen for a further reason, that of improving the yield of the desired product, as shown in Section 1.10.4. 

In semi-batch operation, when the initial charge of A has been consumed, the flow of B is interrupted, the products discharged, and the cycle begun again with a fresh charge of A. If required, however, the advantages of semi-batch operation may be retained but the reactor system designed for continuous flow of both reactants. In 

Examples of possible variations in reactant contacting pattern 

In setting out to design a reactor, therefore, two very important questions to ask are  

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