Caloric Properties in Chemical Reactions

The option of using the standard enthalpy of formation as the reference point in process simulators has the considerable advantage that no further conversions between the reference points of the particular components have to be done. The energy balance of a block involving a chemical reaction can simply be performed by balancing between inlet and outlet of a block. This is illustrated in the following two examples. Chemical reactions are mainly covered in Chapter 12. 

Liquid n-butanol (C4H10O, lOOkg/h, = SO C, P = 1 bar) is combusted with 2000 kg/h air (80 mass% nitrogen, 20 mass% oxygen, = 50 C, P = 1 bar) in a steam generator. The flue gas outlet conditions are 1 = 200 C, P = Ibar. Calculate the duty of the combustor and the amount of saturated steam generated at P = 5 bar, if the feed water is fed to the boiler as a saturated liquid. 

For the vapor phase, the ideal gas equation of state can generally be applied. 

The reaction which takes place in the combustor C4H10O -f- 6O2 4CO2 + 5H2O 

This means that 6 mol O2 per mole of n-butanol are consumed. The molar masses involved are 

---