On the dynamics of distillation processes—I: The simple distillation of multicomponent non-reacting, homogeneous liquid mixtures

Abstract The mathematical theory of multicomponent simple distillation processes is presented. Through the analysis it is possible to deduce the characteristics of this inherently dynamical process. It is shown that every azeotropic point and pure component vertex corresponds to a singular point and that both elementary and non-elementary singular points may arise. It is further shown that the temperature and pressure surfaces are naturally occurring Liapounov functions for this system. The latter part of the paper is concerned with design methods. Rayleigh's design equation is shown not to extend to multicomponent mixtures and an alternative procedure is presented.