Feedback Control of Fed-Batch Bioreactors for Microbial Growth Processes with Non-Monotonic Kinetics

Abstract

This paper deals with the design of a feedback controller for fed-batch microbial growth processes which forces the substrate concentration C s to a desired setpoint c s * , starting from an arbitrary (initial) substrate concentration and when non-monotonic growth kinetics apply. This problem is representative for a lot of industrial fermentation processes, with the baker’s yeast fermentation as a well known example. It is assumed that the specific growth rate μ is function of the substrate concentration only. A first approach exploits the availability of on-line measurements of both the substrate and biomass concentrations. A second approach is based on on-line measurements of the biomass concentration only.