This thesis pretends to be an introduction to the use of thermoeconomics in sulfuric
acid plants. A reference plant with the followings features is examined: a sulfur
burner which oxidizes hydrogen sulfide gases, a wet-catalysis process which is cooled
by means of air quenching, and an absorbtion column that produces sulfuric acid of
78 wt.%. Moreover, the plant has two heat-recovery boilers that produce steam at
40 bar and 5 bar.
The thermoeconomic evaluation consists of three steps: In the first step, an
exergy analysis is performed by using the commercial software CHEMCAD and
the tool CHEMEX, which was designed for this work and takes into account the
activity coefficients of water and sulfuric acid in liquid mixtures for the calculation
of the chemical exergies; In the second step, an economic evaluation is carried out in
order to calculate the plant levelized costs by means of the PEC and cost estimating
techniques; In the third step, both exergy and economic analyses are combined by
distributing the levelized costs among all plant streams, regarding to its exergy
value, in terms of a linear equation system composed of the cost equation of each
plant component and some auxiliary equations. Finally, three possible cost-effective
optimizations are studied regarding to the reference plant by applying the methods
of the thermoeconomic optimization based on thermoeconomic key indicators.Outgoin
