Abstract:
Fatty alcohols possess a wide array of applications and can function as primary constituents in several product categories. Producing fatty alcohols from food waste and lignocellulosic materials such as corn stover may reduce emissions associated with conventional petrochemical-based synthesis and the use of other high-value feedstocks [1], [2]. Currently, the petrochemical sector, which relies on non-renewable resources, is the primary location for the large-scale manufacturing of fatty alcohols [3]. Converting waste into value-added products presents a promising strategy to enhance both economic and environmental sustainability [4].
However, studies on fatty alcohol production from lignocellulosic biomass remain limited, particularly in their integration of process simulation, techno-economic analysis, environmental assessment, and predictive modeling. This study presents a comprehensive techno-economic analysis (TEA) and life cycle assessment (LCA) of fatty alcohol production from lignocellulosic biomass, integrating advanced modeling and machine learning techniques.
The process is simulated using Aspen Plus, with economic evaluation conducted in Aspen Process Economic Analyzer and environmental impacts assessed using openLCA. The fermentation stage employs a vortex-based reactor design, which enhances mass transfer and contributes to improved product yields. To address variability in feedstock composition and operating conditions, we perform thousands of simulations in Aspen Plus to generate a robust dataset of input-output relationships. By coupling the ML-based process model with TEA and LCA calculations, we develop a streamlined framework for evaluating minimum selling price (MSP) and global warming potential across a wide range of scenarios. Experimental data were collected for the concentration of three fatty alcohols: cetyl alcohol (C₁₆H₃₄O), stearyl alcohol (C₁₈H₃₈O), and oleyl alcohol (C₁₈H₃₆O), across different residence times in a vortex-based fermentation reactor. These results enabled the modeling of the vortex reactor in Aspen Plus, using experimentally derived kinetic parameters. In addition to the target fatty alcohols, acetate can be identified as a major byproduct formed during the fermentation process [5].
We conducted over 5,000 Aspen Plus simulations. These simulations generated a comprehensive dataset of input-output relationships, including metrics such as fatty alcohol yield, energy consumption, and acetate byproduct concentration. The dataset was used to train a machine learning model, which accurately predicted process outputs with over 95% R² score and minimal prediction error across key variables. This model was then coupled with TEA and LCA calculations to rapidly estimate MSP and global warming potential (GWP) for a wide range of process scenarios. The results show that the MSP of fatty alcohols is estimated at about $2.0 per kilogram, and the capital cost of the process is around $385 million USD. This uncertainty-informed and data-driven approach significantly enhances the speed and flexibility of scenario analysis, supporting the design and optimization of economically viable and environmentally sustainable bioprocesses.
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