NONLINEAR CONTROL OF A SIMULATED INDUSTRIAL EVAPORATION PROCESS

Three differential geometry based nonlinear control strategies, includ ing input-output linearization, generic model control and Su-Hunt-Meye r transformation were studied on a simulation of the evaporation stage of the liquor burning process associated with the Bayer process for t he production of alumina. The simulation was implemented using a symbo lic algebraic software, Maple V.3. The overall results show that all t hree nonlinear strategies, especially the input-output linearization, provide better control performance than the classical linear control t heory. A simplified solution algorithm for the Su-Hunt-Meyer transform ation is proposed. A brief discussion on the industrial implementation of the nonlinear technology is also given.