(313f) Optimizing the Sugar Beet-to-Isopropanol Supply Chain: A Model Development with Emphasis on CO2 utilization Biotechnology

Annually, the global sugar industry, essential for bio-fermentation processes, is responsible for producing an estimated 170-180 million tons of sugar, including vital components like glucose, fructose, and sucrose [1]. Although research on sugar conversion to valuable chemicals is extensive, the conversion of one economic commodity to another is debated. This highlights the importance of supply chain management and optimization to address inefficiencies. Streamlining and optimizing the supply chain is crucial to making the conversion of sugar to other products economically viable. In the United States, there is a growing trend towards sustainable bio-based isopropanol (IPA) production using genetically modified microorganisms, such as E. coli and Clostridium species. Inspired by the co-culture IPA biosynthesis technique by Papoutsakis et al., which employs C. acetobutylicum and C. ljungdahli [2], our study explores the sugar beet-to-IPA supply chain in Minnesota. Minnesota, producing around one-third of the U.S. sugar beets, offers a promising substrate for bio-based IPA [3].

In this work, a Geographical Information System-enabled framework is utilized, focusing on the production and distribution of bio-based IPA from first-generation biomass. This study analyzes the supply chain from sugar beet to IPA within the state of Minnesota, considering capacity designs across 25 main sugar beet-producing counties to 5 major sugar plants and potential 19 IPA plant locations near existing ethanol plants. The optimization of the sugar beet-to-isopropanol supply chain problem is formulated as a multi-objective Mixed Integer Nonlinear Programming (MINLP) problem. It focuses on biomass logistics planning based on geographical information, as well as bioenergy plant scale design, while taking into account various constraints such as mass balances, facility capacity limits, techno-economic evaluation, environmental impact assessment, and network configuration constraints. The model was implemented on the GAMS platform and solved using the BARON (Spatial Branch-and-Bound) solver. Our findings suggest an optimal production capacity of 55,800 metric tons/year, highlighting the potential for significant emission and operational cost reductions. As demand increases, the financial and environmental costs, particularly from transportation, become increasingly significant. This study not only emphasizes the feasibility of bio-IPA production in achieving sustainability goals but also the critical role of supply chain optimization in enabling this transition, offering insights for sustainable innovation and investment in the bio-IPA sector.

References

[1] Lopes, M. S. G. Engineering biological systems toward a sustainable bioeconomy. Journal of Industrial Microbiology and Biotechnology 2015, 42 (6), 813-838.

[2] Charubin, K., Gregory, G. J., & Papoutsakis, E. T. (2021). Novel mechanism of plasmid-DNA transfer mediated by heterologous cell fusion in syntrophic coculture of Clostridium organisms. bioRxiv, 2021-12.

[3] Beef2Live. (n.d.). Ranking Of States That Produce Sugarbeets. Accessed: Nov 6 2023, from https://beef2live.com/story-ranking-states-produce-sugarbeets-0-212386.