ROBUST OPERATION OF FED-BATCH FERMENTERS

Optimisation of fed batch fermenters can substantially increase the pr ofitability of these processes. Optimal control of a fed batch ferment er is usually based on a nominal process model. Parameter uncertaintie s are not taken into account. Simulation studies show that results obt ained with fixed nominal model parameters can be quite sensitive to th e uncertainty in parameter values. This paper presents a method for ob taining robust optimal control profiles in the presence of uncertainty in the model parameters. The proposed approach is illustrated with a case study. It is also shown that feedback controllers can reduce the effect of the uncertainties.