Nonlinear PI control of an ethylene glycol reactive distillation column

The control problem of an ethylene glycol reactive distillation column is studied in this work. The control objective is to regulate the ethylene glycol composition in the product by manipulating the reboiler boil-up ratio. By using an estimator of the input-output modeling error, a first-order output-feedback compensator is designed which is shown to be equivalent to a PI controller with antireset windup structure. The ability of the controller to regulate the product composition in the face of unknown nonlinearities and sampled/delayed measurements is shown via a numerical simulation on a rigorous dynamical model.