Analytical first-order dynamic model of binary distillation column

Abstract

Matrices of transfer functions have been developed for the concentration dynamics of the rectifying and stripping sections of distillation columns. Responses of the model concentrations to fluid flow changes through the column are of first-order lag form. The parameters, of the transfer functions are analytically expressed completely in terms of basic design parameters and hold up. For the first time the complete analytical dynamic model, corresponding to the McCabe—Thiele static model, is obtained, thus opening the possibility of formulating a universal theory of binary distillation column control, instead of studying particular cases. The derived model is directly applicable, because it is sufficient to have only the basic design data in order to obtain good approximations of all the model parameters. This type of model could also be considered as generally applicable to the separation processes.