Gibbs Minimization

Lili Lyddon

March 23, 2007

The Gibbs Minimization reactor in ProMax has the advantage that stoichiometric equations are not required. Equilibrium is determined from the free energy and the heat of reaction is calculated automatically. The method is completely general and predictive. Processes which come to equilibrium or close to equilibrium may be modeled with this technique. ProMax allows the user to choose which components are reactive and which are inert. Setting components reactive and inert is an important aspect in modeling sulfur plants. In the refinery, a hydrogen plant may be modeled using two Gibbs Minimization reactors for the reformer and shift converter. In the higher temperature reformer most or all components are allowed to react. The temperature in the shift converter is lower and only the components in the water-gas shift reaction (CO + H2O = CO2 + H2) are allowed to react.

Authored by Lili Lyddon (BR&E Technical Support and Help Author)