Journal of Process Control, Vol.23, No.5, 778-792, 2013
Increasing the reactant conversion through induced oscillations in a continuous stirred tank reactor by using PI control
We report a strategy to increase the reactant conversion in a continuous stirred tank reactor (CSTR) to produce propylene glycol through induced oscillations generated by two controllers PI1 and PI2 that manipulate the reactor outlet flow and the coolant flow rate respectively. It is shown that an adequate parameter choice for the PI controllers allows one to derive sustained oscillations in the concentrations and reactor temperature, which in turn allows increasing the propylene glycol production. For a suitable choice of the PI1 and PI2 controller parameters, we use a complete reactor model that provides with physically feasible parameters. The issues of external disturbance rejection, self-oscillations and stability have also been discussed. The analytical calculations are verified by means of full numerical simulations. (C) 2013 Elsevier Ltd. All rights reserved.