Modeling and optimization of bioethanol production via a simultaneous saccharification and fermentation process using starch

摘要

BACKGROUND: Bioethanol is an attractive alternative fuel because it is less carbon-intensive than oil and is also a renewable bio-based energy source. The aim of this study is to present a mathematical modeling approach in order to describe the simultaneous saccharification and fermentation process of the yeast Saccharomyces cerevisiae YPB-G for the production of bioethanol using starch. RESULTS: An unstructured model was proposed for model parameters that are independent of initial operating conditions, but have a highly predictive capability that can be used in process optimization and control. The predictions of the proposed models were compared with experimental data and against the results of other models presented in the literature. CONCLUSION: A technique of gradually expanding the search domain combined with a genetic algorithm was proposed to successfully speed up the optimization computation of parameter estimation. Compared with an earlier model presented in the literature, the proposed model shows more versatility with fewer numbers of parameters and fixed values of parameters, and provides a satisfactory prediction capability. The proposed model was used to investigate the process optimization of batch culture. Numerical results may provide various process alternatives for planning the productivity of bioethanol.