H2SO4 making calculations

Chapter 23 examines the input of moist metallurgical and spent acid regeneration gases into Fig. 23.1 s dehydration tower. It quantifies the amount of H20(g) that enters dehydration tower acid  

This appendix examines H20(g) in sulfur burning acid plants. It  

This greatly simplifies our sulfur burning H20(g) calculations (Section V.l). 

This section duplicates Section 23.4.1 s calculation of kg mol H20(g) into dehydration tower acid per kg mol of dry first catalyst bed feed gas. 

The moist air being fed to the Fig. V.I s sulfur burning dehydration tower is specified to contain  

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Chapter 19 s S02 oxidation calculations assume that 100% of the SO3 entering H2SO4 making reacts to form H2S04(f). This appendix s calculations remove that restriction. They also consider C02 in feed gas. 

Fig. 19.2. Double contact acidmaking flowsheet with numerical values used in this chapter s calculations. The plant consists of 3 catalyst beds followed by intermediate H2SO4 making and a 4 catalyst bed. The gas from the last catalyst bed goes to cooling and final H2SO4 making (not shown). All kg-mole values are per kg-mole of D catalyst bed feed gas. Gas pressure = 1.2 bar, all beds.

Calculate the equivalent SO2 oxidation efficiency with 4 catalyst beds but no intermediate H2SO4 making. Use the technique described in Appendix S with all of Prob. 19.1 s temperatures and pressures. 

Fig. 20.5. 3 - 1 acid plant with one Cs catalyst bed (660 K gas input) and three K, Na catalyst beds (690 and 720 K). Maximum SO2 oxidation is obtained with the Cs catalyst in bed 4, i.e. after H2SO4 making. Bed 3 Oust before H2SO4 making) is nearly as good. The calculations are all based on Table 20.1 s values - except for gas input temperature. 

Fig. 21.1. Heat transfer flowsheet for single contact, suliiir burning sulfuric acid plant. It is simpler than industrial plants, which nearly always have 4 catalyst beds rather than 3. The gaseous product is cool, SO3 rich gas, ready for H2SO4 making. The heat transfer product is superheated steam. All calculations in this chapter are based on this figure s feed gas composition and catalyst bed input gas temperatures. All bed pressures are 1.2 bar. The catalyst bed output gas temperatures are the intercept temperatures calculated in Sections 12.2, 15.2 and 16.3.

K H2SO4 making input gas temperature. This heat removal is calculated by the equation ... 

Use your Prob. 16.1 3 catalyst bed output quantities and Eqn. (21.3) to calculate H2SO4 making s input gas enthalpy. 

Calculate the rate, MJ/hour, at which heat must be transferred from 3 catalyst bed exit gas to economizer water to obtain the above specified 470 K H2SO4 making gas. 100 000 Nm per hour of catalyst bed feed gas is entering the 1 catalyst bed. 

Fig. 23.1. Simplified single contact sulfuric acid production flowsheet. Its inputs are moist feed gas and water. Its outputs are 98 mass% H2SO4, 2 mass% H2O sulfuric acid and dilute SO2, O2, N2 gas. The acid output combines gas dehydration tower acid, H2SO4 making tower acid and liquid water. The equivalent sulfur burning acid plant sends moist air (rather than moist feed gas) to dehydration. Appendix V gives an example sulfur burning calculation.

Fig. 24.1. Fig. 23.1 s single contact H2SO4 making tower. Its temperatures and gas compositions are used in Section 24.1 and 24.2 s calculations. The calculations assume that all input S03(g) reacts to form H2S04( ). Note that output gas temperature = input acid temperature. ( Hay et al., 2003). 

Fig. 24.5. Effect of S03(g)-in-input-gas concentration on H2SO4 making output acid temperature. Output acid temperature decreases slightly with increasing SOs(g) concentration. The volume% SO3 values have been calculated as described in Chapter 16 starting with 8, 9, 10, 11 and 12 volume% SO2 in 1 catalyst bed feed gas.

Calculation of H2SO4 Making Tower Mass Flows... 

The Fig. 24.1 H2SO4 making tower s mass flows are calculated by specifying ... 

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