Examples of Continuous Reactor Models

A reactor model based on solid particles in PF may be used for situations in which there is little or no mixing of particles in the direction of flow. An example is that of a conveyor belt carrying the particles others that approximate this include a rotating 

In such a case, the particles all have the same residence time, and the RTD is represented by the 5 function  

If all particles are of the same size, equation 22.2-5 is also the model for the reactor. This result can also be obtained from equation 22.2-3, since then 

In this case, the performance of the reactor is governed entirely by single-particle kinetics (e.g., as given in Table 9.1). 

For the gas-solid reaction A(g) + bB(s) - products [(s), (g)], calculate the solid holdup (WB) required in a reactor for /B = 0.80, if FBo = 50 kg min-1 and t] = 1.5 h. Assume the following apply the solid particles are in PF, the gas is uniform in composition, the particles are spherical and all of one size, the reaction is a first-order surface reaction, and the SCM applies, with ash-layer-diffusion control. 

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