BAYER PROCESS CONTROL AT ALCAN VAUDREUIL WORKS

Alcan Vaudreuil Works is the only alumina plant in Canada. The plant produces about 1.4 milion tons of alumina per year, using the Bayer process to treat bauxite ore. In addition to regulatory control, this complex extraction process involves many applications of advanced process control. Techniques such as adaptative control, multivariable control (model based predictive control), fuzzy logic, on-line models and expert systems are used. This paper will first introduce the Bayer process and present the different types of control commonly used. Three examples of closed loop advanced process control applications will be presented.