SO3 Input Mass

The gas entering Fig. 23.1 s H SO making ( absorption ) tower is specified to be Section 16.3 s 3 catalyst bed exit gas. It contains  

Only the SO3 participates in HiSOj making. It is specified that it all ends up as H S04(.f). Reaction (1.2). 

4 H20(g) Input from Moist Acid Plant Input Gas 

This gas is dehydrated in Fig. 23.Ts dehydration tower. Its H20(g) reacts with strong sulfuric acid in the tower to form  

This section calculates the mass of H20(g) in 5 mole% H20(g) input gas. It is specified that all of this H20(g) ends up in Reaction (6.2) s slightly weakened acid. 

4 H20(g) input from moist acid plant input gas 

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Fig. 23.2 shows mass H2SO4 out of Fig. 23.1 s H2SO4 making tower as a function of the tower s input SO3 quantity. H2SO4 production (kg) increases linearly with increasing SO3 input mass (kg). 

Fig. 23.5. Acid plant water requirement as a function of mass SO3 into H2SO4 making tower. The water requirement increases with increasing SO3 input mass, Section 23.7.4. With a 100% H2SO4 product, the slope is 0.225 (Fig. 23.2). With 2 mass% H2O, 98 mass% H2SO4 product acid, it is 0.25 (as shown). It varies, therefore, with product acid composition.

Description equation numerical term mass SO3 Into H2SO4 making tower mass H2O in moist Input gas mass Input water mass H2SO4 in output acid mass H2O in output acid... 

In terms of mass, each 80 kg of input SO3 gives 98 kg of output H2SO4. This is equivalent to ... 

Fig. 23.3. Fig. 23.1 acid plant water requirement as a function of volume% H20(g) in acid plant input gas. Water input requirement decreases with increasing volume% H20(g). The graph applies only to its specified input SO3 mass and product acid composition. 

H2SO4 production increases with increasing SO3 mass in H2SO4 making tower input gas, both per kg-mole of dry 1st catalyst bed feed gas. Acid plant water requirement increases commensurately. 

Table 24.1, Fig. 24.1 s inputs and outputs. Input and output kg-mole of SO3, SO2, O2 and N2 are from Fig. 24.1. Input and output H2SO4 and H2O masses are calculated in Appendix W. They are all used to calculate Fig. 24.1 s output acid temperature. The H values have been calculated by the equations in Appendix G. (kg-mole H2SO4 = kg H2SO4/98. kg-mole H2O = kg H2O/18)...

Of course, output acid temperature will increase if mass% H2SO4 in output acid is allowed to increase with increasing volume% SO3 in H2SO4 making tower input gas. Fig. 24.4. This is the case when input acid flowrate and mass% H2SO4 are kept constant while volume% SO3 in input gas increases. This is usual industrial practice. 

Description Equation Numerical term Mass SO3 into H2SO4 making tower Mass H2O in moist input gas Mass input water Mass H2SO4 in output acid Mass H2O in output acid... 

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