(66b) Incorporating Unsteady-State Fermentation Models in Aspen Plus: Fed-Batch and in Situ Gas Stripping Simulation and Analyses
In our previous study, the batch acetone-butanol-ethanol (ABE) fermentation was used as a model system to simulate an unsteady-state batch ABE fermentation using a Fortran user kinetics subroutine linked to the batch reactor (RBatch) in Aspen Plus as a starting point for a biorefinery. This study extends the Aspen Plus batch model to fed-batch fermentation and in situ gas stripping with the aim of comparing the trends in the simulation to their corresponding laboratory fed-batch and in situ gas stripping experiments. An existing ABE fermentation model was reformulated to describe cell growth and inhibition using Monod kinetics, making it sensitive to changes in the fermentation environment as a result of fresh substrate addition (fed-batch) and product accumulation. This study provides a platform that can be used to guide integrated fed-batch fermentation and in situ gas stripping experiments and assess the accuracy of literature data. Additionally, a universally accepted process simulator, Aspen Plus, can be used in the simulation of fermentation processes linked with separation unit operations to provide strategies for the design and optimization of biorefineries.