Significance of Heatup Path Position and Slope

660 K feed gas heatup path will reach the equilibrium % SO2 oxidized curve  

This predicts high SO2 oxidation efficiency with low feed gas temperature. This prediction is discussed extensively in Chapter 12 onwards. 

SO2 oxidizes and gas temperature increases as SO2, O2, N2 gas descends through active V, alkali metal, S, O, Si02 catalyst. This behavior is shown by the heatup paths of this chapter. 

Chapters 12 onwards combine these heatup paths with Chapter lO s % SO2 oxidized equilibrium curves to show how  

They indicate that cool feed gas (but warm enough for rapid catalytic oxidation) gives efficient SO2 oxidation and small SO2 emission. 

79 volume% N2 feed gas. Notably, the 660 K heatup path will reach the equilibrium curve at a higher % SO2 oxidized value than the 690 K heatup path. 660 K is about the lowest feed gas temperature that will keep V, Cs, K, Na, S, O, Si02 catalyst active and SO2 oxidation rapid (Table 8.1). 

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