An alternative approach for oscillatory behaviour control in a nonlinear bioprocess

The nonlinear nature of bioprocesses often leads to the occurrence of the self-sustained oscillations of the biomass concentration in continuous flow bioreactors. For some practical reasons, sometimes it is necessary to control the oscillatory behaviour, which is usually achieved by changing the dilution rate, but this is not always the best option. Hence, the main idea of this paper is to introduce an additional substrate, which has been previously diluted. Based on the numerical analysis of an unstructured mathematical model, it is shown that by mixing two various substrates (the main and the diluted one), it is possible to induce or eliminate the sustained oscillations. As a result, the contribution of both substrates to the mixture and the degree of dilution of the additional substrate can be treated as new control variables.