QUASILINEARIZATION, PARAMETER ESTIMATION, AND DISTILLATION COLUMN DESIGN

Abstract

A multicomponent distillation column design problem is solved by the combined use of estimation and quasilinearization. The design problem can be stated as follows: obtain a specified purity of certain products from a given feed mixture by the use of an existing column. The only variable within the designer's control is the reflux ratio. Several different formulations are solved by the quasilinearization approach. It is shown that the concept of treating multi-component distillation as nonlinear boundary value problems forms a powerful and versatile computational tool. Furthermore, this approach can be extended easily to problems with over-specified conditions with the help of some minimization criterion. The technique is also ideally suited for the dynamic control of a distillation column where a constant purity of certain products over time is desired.