Inferential control of a sidestream distillation column

This paper deals with the advanced control of a side-stream distillation co lumn removing benzene from a reformed gasoline stream. A multivariable cont rol strategy based on two SISO schemes, each controlling the benzene concen tration in an outlet stream has been developed. Each SISO loop is a cascade one and consists of a secondary loop devoted to control pilot tray tempera ture and a primary inferential controller of the benzene composition based on a short-cut physical model. The decoupling between the two single loops was obtained by keeping the internal reflux between the side-stream tray an d the bottom tray constant. (C) 2000 Elsevier Science Ltd. All rights reser ved.