Calculation of chemical equilibria in heterogeneous multicomponent systems

A technique has been developed for the calculation of chemical equilibrium of a closed multicomponent heterogeneous system for the given values of temperature, pressure and feed composition. The method is based on the consecutive exclusion and inclusion of the phases from and into the calculation process till the system is thermodynamically stable with respect to the phases not included in the system. Thermodynamic stability is tested using the Kuhn-Tucker condition. Proof of convergence of the proposed iterative process is given, allowing a test of the validity of Kuhn-Tucker condition to be made. Convergence of the whole calculation process is also discussed.