Control Strategy for a Zymomonas mobilis Bioreactor Used in Ethanol Production

摘要

High oil prices, increasing focus on renewable carbohydrate-based feedstocks for fuels and chemicals have provided continuing stimulus for studies on Zymomonas mobilis bacteria. The ethanol production with this bacterium shows interesting nonlinear dynamic behaviors. In the continuous fermentation, there are equilibrium multiplicity, Hopf points and stability changes. Various models have been proposed in the literature (Daugulis et al., 1997; Jarsebski, 1992; Ghommidh et al., 1989; Jobses et al., 1986) for to describe such phenomena. In special, the Jobses' model has captured these behaviors and revealed an attractive operating range with high substrate to product yield. This article presents a multivariable control strategy for the continuous ethanol synthesis through Z. mobilis, in a high yield solution branch inside the steady-state multiplicity region.