Dynamic Optimization of Fed-batch Fermentation with Constraint on Wastewater Discharge

Abstract

A fed-batch culture is a semi-batch operation in which the feed streams are added intermittently or continuously during the operation course and the products are harvested only at the end of the run. Optimal feed streams input profiles that harvest the maximum production can be obtained by dynamic optimization. However, the optimal profile may be quite different if the constraint on wastewater discharge is considered. In this paper, the penicillin fermentation process is adopted as a case study, and we propose a constraint to evaluate the wastewater discharge. The dynamic simulation results show that the optimal results with the constraint of wastewater discharge may decrease 40~50 % in penicillin production, compared with the one without the constraint, which indicates that constraint on wastewater discharge has a significant influence on the optimal fed-batch process, and needs especial attention for decision making at the beginning stage of the process development.