(161b) Techno Economic Analysis and Life Cycle Assessment for Synthetic Spider Silk Production

Synthetic spider silk has emerged as an innovative biomaterial, notable for its exceptional strength and thermal resistance. Its applications range from textile production to medical instruments. The advancement of synthetic biology has facilitated the generation of recombinant spider silk proteins, utilizing Escherichia coli (E. coli) as a production host, and introducing a sustainable alternative to traditional materials. This paper explores the economic viability and environmental implications of synthetic spider silk manufacturing on a large scale. To assess the feasibility of synthetic spider silk production, a techno-economic analysis (TEA) was conducted to examine the economic aspects of the manufacturing process.

This analysis considered various factors, such as production costs, market demand, and potential profitability, to evaluate the economic feasibility of large-scale production. In addition, a life cycle assessment (LCA) was performed to analyze the environmental impact of the production process, covering the complete life cycle of synthetic spider silk, from raw material extraction to end-of-life disposal. Based on laboratory data, we developed and validated a comprehensive process model that encapsulates the essential phases of synthetic fiber production, including Bacterial Cell Culture, Protein Separation, and Fiber Processing, within the BioSTEAM environment.

A detailed techno-economic assessment reveals that the cost of producing spider silk can vary significantly, depending on the operational efficiency and technological maturity of the production facilities. The results indicate a minimum sale price of 29 USD per kilogram and associated greenhouse gas (GHG) emissions of 38 kg CO2-equivalent per kilogram of silk produced. These outcomes are attributed to enhanced protein yields, process optimizations, and economies of scale inherent in mature production operations.

Compared to natural silk fiber, which has a reported environmental impact of 58.73085 kg CO2 equivalent, our synthetic spider silk production demonstrates a reduced global warming potential of 43.43 kg CO2 equivalent, underscoring the environmental benefits of our approach. Furthermore, sensitivity analysis conducted in this study identifies the key techno-economic analysis parameters affecting the minimum sale price of the silk. Notably, fiber yield, measured in kg/kg of glucose, emerged as the most significant factor, followed by the cost of raw materials. This analysis underscores the importance of optimizing yield and managing raw material costs to enhance the economic and environmental sustainability of synthetic spider silk production.

In this study, various fiber yield percentages were analyzed to determine their impact on the minimum selling price (MSP) of synthetic spider silk. The findings reveal that at a 16% fiber yield, the MSP is 29 USD per kilogram, whereas a lower yield of 4.5% results in a significantly higher MSP exceeding 100 USD per kilogram. Conversely, achieving a higher fiber yield of 27% reduces the MSP to 18 USD per kilogram, highlighting the crucial influence of fiber yield on the economic viability of synthetic spider silk production and more research is needed to understand how other fiber qualities might affect the value and benefits of the synthetic fibers.