INVESTIGATION OF VAPOR-LIQUID-EQUILIBRIUM OF NONIDEAL MULTICOMPONENT SYSTEMS

Fundamentals and computer-aided methods of practice for the calculatio n and checking of azeotropes, and for the qualitative nd rigorous dete rmination of separating spaces for closed distillation are presented, which are valid for non-ideal multicomponent systems. Separating space s can occur in azeotropic systems only and are decisive for the separa bility of a system, if distillation is the separation technique. As a prerequisite, a rigorous mathematical model of the vapour-liquid equil ibrium is required. The eigenvalues and eigen vectors of the Jacobian matrix of the equilibrium concentrations are the key ingredients of se veral methods: the eigenvalues describe the asymptotic behaviour of cl osed distillation profiles, which indicates the order according to whi ch components can be separated; the eigenvalues enter a topological eq uation for checking the thermodynamic consistency of the azeotropes of a system; the eigenvectors initiate paths connecting azeotropes and p ure substances, from the network of which separating spaces can be ded uced qualitatively; and eigenvectors are essential to initiate the rig orous profiles of separating spaces. Copyright (C) 1996 Elsevier Scien ce Ltd.