Decentralized control with minimum dissolved oxygen guaranties in aerobic fed-batch cultivations

NÚÑEZ, S.; GARELLI, F.; DE BATTISTA, H.

INDUSTRIAL & ENGINEERING CHEMICAL RESEARCH

AMER CHEMICAL SOC

Lugar: Washington; Año: 2013 vol. 52 p. 18014 - 18021

0888-5885

In this  work, a control strategy to guarantee a minimum dissolved oxygen concentration  in aerobic fed-batch bioprocesses is proposed. The strategy is equally  applicable to avoid low oxygen concentrations that might be detrimental for  metabolites production, to prevent metabolic changes and to maintain an oxygen  level in the culture compatible with the desired growth rate during the growing  phase of the process. It essentially consists in adapting the set-point of the  feeding controller to cope with faults and saturation in the oxygen regulation  subsystem. The idea behind this adaptation is to manipulate, when necessary,  the oxygen consumption in such a way that the oxygen in the culture is  maintained above a prescribed threshold. The algorithm is based on sliding mode  techniques, and its main features are as follows: simplicity, robustness to  process uncertainties, easy implementation, and versatility to be combined with  different dissolved oxygen and feeding controllers. The method is assessed  numerically in a fed-batch growth phase of Pichia pastoris where an oxygen  shortage leads to excessive glycerol accumulation.