Discussion of Books Assumptions

This section discusses these three assumptions. 

Sulfur burning acid plants operate steadily almost all the time. The main significance of this is that temperature is constant at every point in the plant s catalyst beds. It means that none of the gas s heat is being used to heat catalyst. 

Metallurgical and spent acid regeneration plants are not quite so steady, but the steady state assumption is still reasonable. 

The assumption of no conductive, convective plus radiative heat loss fi-om catalytic SO2 oxidation converters is not perfectly correct. There is always some heat loss. Nevertheless  

It is not easy to know how close industrial catalytic SO2 oxidation comes to equilibrium. Our opinion is that it comes quite close, especially if the beds are run somewhat above their catalyst activation temperature. The effect of non-attainment is demonstrated in Fig. 18.10. 

SO that heat loss per kg mol of gas is generally small. This is true for average to large-sized plants. However, smaller plants have high heat loss per kg mol of gas which must be included in their design. 

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