Increasing the reactant conversion through induced oscillations in a continuous stirred tank reactor by using PI control

Abstract

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 PI 1 and PI 2 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 PI 1 and PI 2 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.

Size Control, Chemical Kinetics, and Theoretical Analysis for the Production of Fe3O4 Nanoparticles with a High Specific Absorption Rate

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Sustainability and process control: A survey and perspective

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A New Homotopy-Based Strategy for the Robust Determination of All the Feasible Solutions for CSTR Systems

“…The nonlinearity is reflected in the form of multiple steady states and a 1 Chemical Process Engineering, Faculty of Technology, University of Oulu, PO Box 4300, FI-90014 University of Oulu, Finland multiform dynamic behaviour including instability, sustained oscillations, and phenomena such as strange attractors and chaotic behaviour (see e.g. Jayakumar et al [14]; Kiss et al [4]; Pérez-Polo and Pérez-Molina [15]; Razón and Schmitz [16]; Russo and Bequette [17]). …”