(82c) Bioprocess Design and Techno-Economic Evaluation of 2,3-Butanediol Production from Crude Glycerol and Sugar-Based Feedstocks

2,3-Butanediol (BDO) production from crude renewable resources is a potential platform chemical for the development of a sustainable chemical industry. Fed-batch fermentations for BDO production have been optimised using very high polarity sugar and molasses derived from sugarcane mills as well as crude glycerol from biodiesel production plants. Fermentation media, volumetric oxygen transfer coefficient (k_La), temperature and pH were considered in the optimization of individual fed-batch cultures. The optimal fermentation efficiencies (i.e. fermentation medium composition, yield, productivity, final BDO concentration) were used in bioprocess design simulations using the software UniSim (Honeywell) that was used to validate material and energy balances. The downstream separation and purification section was based on the conversion of BDO into an acetal that is immiscible with water followed by distillation steps. An alternative downstream separation and purification process was also evaluated based on the direct conversion of BDO into methyl ethyl ketone (MEK). Preliminary techno-economic evaluations were carried out for all feedstocks, associated fermentation efficiencies and downstream separation alternative process flow sheets showing the bottlenecks for industrial implementation. Sensitivity analysis was subsequently conducted considering the most important parameters in order to identify the process improvements required for the industrial implementation of BDO or MEK production. The results presented in this study demonstrate that crude glycerol is a promising feedstock for the production of BDO and MEK.

Acknowledgements

The work presented in this study has been funded by the National Agency of Petroleum (ANP), Petrobras, Brazil (project 00320-2/ 2012