Abstract
Continuous Stirred Tank Reactor (CSTR) represents an important equipment in various chemical processes. To achieve optimal productivity, this installation must be kept in safety working conditions at superior conversion rates. Our paper addresses the stationary operating regime stability of the non-isothermal processes, starting from CST's nonlinear mathematical model. In addition, it proposes a closed loop control design for stability and performance for this type of systems. The mathematical model is computed and the stability geometrical conditions for a non-isothermal reactor in a stationary plane are determined. The conditions which were detected grant some stable operating demands for the nonlinear reactor model accomplished for minor oscillations about a stationary point. By applying Lyapunov first stability theorem on the linearized model, the necessary and requirements conditions of stability for CSTR are demonstrated. Finally, an adequate closed loop state control is proposed to avoid the thermal avalanche phenomenon. The control solution ensures stability and provides high performances for the exothermic nonlinear reactor. An analytical case study and simulations enforce the adequacy of this theoretical approach.