Dynamics and control of continuous reactive crystallization processes

Control of two continuous reactive crystallization processes, one for the production of barium sulfate and one for the production of L-glutamic acid, is investigated. In both processes, the crystal mass production rate and the volume mean size of the product are controlled by manipulating the reactant inlet volumetric flow rates and the holdup in the crystallizer. The reactant inlet concentration, nucleation rate, and temperature of the crystallizer are considered as disturbances. The control structures provide good performance for 10% changes in disturbance variables and setpoint changes. Furthermore, stability analysis is performed for both processes and operating regions where continuous oscillations in solute concentration and crystal size distribution can occur are identified. ? 2016 Taiwan Institute of Chemical Engineers.