In this paper, we address dynamic controllability of the two different designs of extractive fermentation process, namely one-stage and two-stage designs. The operating conditions that maximize yields and productivity for both designs are determined by optimization using the method of factorial design and response surface analysis. The results show that in terms of the achievable yield and productivity, the performance of the two-stage design is comparable to that of the single-stage, but the former design leads to a significant reduction in the fermentor size required. Furthermore, we analyze the dynamic controllability of the two designs of extractive fermentation process using a so-called control relevant metrics to examine their closed-loop dynamic performance in the face of uncertainty. This analysis reveals that the single-stage design has more favorable dynamic controllability than the two-stage design.
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