Thermodynamics for Process Simulation and ICME

ChemApp opens up new horizons for the use of thermochemical calculations across a wide spectrum of applications. It offers you great flexibility to design and implement FactSage calculation techniques in whichever way YOU want and is therefore the perfect tool to include robust thermodynamics in process simulation software or Integrated Computational Materials Engineering (ICME) approaches.

Applications for the use of ChemApp are almost limitless and can cover an extremely diverse range of applications. Two distinctly different groups of applications of ChemApp are possible:

  • using it for the development of application-specific programs; for example, for handling repetitive complex equilibrium calculations, for analysis, and for process control in well-defined technological areas,
  • linking it to third-party process simulation packages for modelling new or optimising existing processes; for example, commercial CFD programs such as Phoenics, CFX®, etc., general simulation programs, including Aspen Plus®, and also your company’s own process simulation program.

By embedding it in appropriate code, ChemApp can be employed to investigate time-dependent and kinetic effects using the concept of “local equilibria”.

Figure 1: Schematic representation showing the integration of ChemApp into process modeling or simulation programs.


Install and use ChemApp on a large variety of computer platforms and use your favourite programming language (e.g. FortranCC++,Visual Basic®, or Delphi®). A few lines of easy-programmable code will convert ChemApp into a powerful computational tool that will improve existing capabilities, or provide totally new ones; and enhance your efficiency and competitiveness.

ChemApp uses the calculational ‘engine’ and the data-handling capabilities of FactSage. You find the same speed and reliability of convergence of calculations. You can use the same thermochemical data combined with the same comprehensive library of models for non-ideal solution phases (Table 1). That means that we can also supply you with all the data that you need for your application!

Table 1: List of available solution models in ChemApp. Except for the gaseous and aqueous models, pressure-dependent contributions to the Gibbs energy are permitted. High temperature/high pressure contributions (up to 1Mbar and 6000K) for pure substances are modelled with the Birch-Murnaghan multicomponent model. Magnetic contributions are not permitted for phase models marked with an asterisk (*)

Model Application area
Four-suffix Margules
for general use with substitutional or associated solution phases
Compound energy formalism
Two sublattice order/disorder formalism
Species chemical potential/bond energy formalism*
solid alloys
Ionic two sublattice model* ionic liquids
Two-sublattice equivalent fraction formalism
Two-sublattice equivalent fraction formalism as a polynomial
Guts formalism
molten salts
Gaye-Kapoor-Frohberg cell model*
Blander-Pelton modified quasichemical model*
ionic oxidic mixtures with non-oxidic solutes
Wagner metallic dilute solutions
Davies formalism*
Pitzer formalism without E-theta and E-theta’*
concentrated aqueous solutions
Revised Helgeson-Kirkham-Flowers (HKF) Model* Applicable to the calculation of standard and non-ideal mixing properties up to 5 kbar and 1300K; e.g., for those involving complex aqueous solutions
C-H-O-S-N-Ar Multicomponent Fluid Model* Used for calculations involving non-ideal multicomponent fluid mixtures up to 1 Mbar and 6000K; it is important for many geological and environmental systems
Virial equation with Tsonopoulus second virial coefficient correlation* non-ideal gas phases

Use GTT-Technologies’ data service to get thermochemical data for your use. We provide data in all forms, ranging from single application-specific data-files to comprehensive databases. And if you cannot find what you want among these readily available sources, we also prepare ‘customised’ data-files to meet your specific requirements.