Catalyst Bed Heatup Path

Fig. 13.2. 1st catalyst bed heatup path, equilibrium curve and intercept point, from Fig. 12.1. The 1st catalyst bed s exit gas is its intercept gas, Section 12.12. It is cooled and fed to a 2nd catalyst bed for more S02 oxidation.

Fig. 14.2. Sketch defining Section 14.4 s 2nd catalyst bed heatup path problem.

The 2nd catalyst bed heatup path is prepared by re-doing Section 14.9 s calculation for many different temperatures in the bed. Only cells HI5 to K15 are changed (most easily with enthalpy equations in cells, Appendix K). The results are tabulated in Table 14.3 and plotted in Fig. 14.3. 

Chapter 14 describes 2nd catalyst bed heatup paths. This chapter describes 2nd catalyst bed ... 

This chapter s 3rd catalyst bed heatup path is calculated much like Chapter 14 s 2nd catalyst bed heatup path. Differences are ... 

Fig. 16.2. Specifications for (i) 2-3 cooldown and (ii) 3rd catalyst bed heatup path and intercept calculations. The 1st and 2nd catalyst bed exit gas quantities are equivalent to ...

Appendix N shows a 3rd catalyst bed heatup path matrix with these equations. It also shows several heatup path points. Figs. 16.3 and 16.4 show the entire heatup path. 

Table 17.1. 1st catalyst bed heatup path worksheet with 0.2 volume% S03 and 9.8 volume% SO2 in feed gas. It is similar to Table 14.2 s 2nd catalyst bed... 

C02-in-feed-gas affects catalyst bed heatup paths and intercepts (but not equilibrium curves, Appendix F). The remainder of this chapter indicates how C02-in-feed-gas affects ... 

Table 17.3. Is1 catalyst bed heatup path matrix with S03 and C02 in feed gas". Cells D15 to H15 contain -H°9QK values. Cells 115 to M15 contain H°2QK values. All are calculated with Appendix G s enthalpy equations. 820 K part way down the catalyst bed is shown to be equivalent to oxidation of 46.7% of the feed gas s S02. 

Fig. 17.1 shows the effect of C02 on a 1st catalyst bed heatup path and intercept. C02 has no effect on equilibrium curves, Appendix F. 

Fig. 17.1. Effect of C02-in-feed-gas on 1st catalyst bed heatup path and heatup path-equilibrium curve intercept. C02 increases heatup path slope and slightly increases intercept (equilibrium) % SO2 oxidized. Section 17.4. Appendix Table R.l describes the 10 volume% C02 intercept calculation.

Table 21.1. Bottom half of Table O.l s 3rd catalyst bed heatup path-equilibrium curve intercept worksheet. Input and output gas enthalpies are shown in rows 43 and 44. Note that they are the same. This is because our heatup path calculations assume no convective, conductive or radiative heat loss during catalytic SO2+V2O2 —> SO3 oxidation, Section 11.9. 1st and 2nd catalyst bed enthalpies are calculated similarly - using Tables J.2 and M.2. 

Table J.l. Worksheet for calculating 1st catalyst bed heatup path-equilibrium curve intercept. Preparation instructions are given in Section J.3. Operating instructions are given in Section J.4. Notice that equilibrium curve % S02 oxidized (cell FI 1) heatup path % S02 oxidized (cell 139). So 894.2 K in cells A14 and J30 is not the intercept temperature. The intercept value is calculated in Table J.2. 

Table K.l shows a 2nd catalyst bed heatup path matrix with enthalpy-as-a-fiinction-of-temperature equations in cells D15 to K15. The only difference between this matrix and the Table 14.2 matrix is that Eqn. 14.9 in row 15 has been changed to ...

Table N. 1 is a 3rd catalyst bed heatup path worksheet. It is a copy of worksheet Table K. 1 with ...

Table N.l. 3rd catalyst bed heatup path matrix with enthalpy equations in cells D15-K15. The numerical quantities in cells C8-C11 are Table M.2 s 2nd catalyst bed intercept quantities. 

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