AbstractThe production of biofuels is an alternative to reduce the impacts of the transformation of fossil fuel sources. In this work, the evaluation of ethanol production from the bagasse obtained during non-centrifuged sugar production (BNCS) to determine its sustainability in the Colombian context is proposed. Two pretreatments (i.e., dilute acid and alkaline) are proposed, followed by enzymatic saccharification to release glucose from cellulose. Both liquors rich in C6 sugars were followed by a fermentation stage with Saccharomyces cerevisiae, and the obtained ethanol concentration was measured. The process was simulated and evaluated to obtain metrics in technical, economic, environmental, and social terms. Also, an evaluation of the sustainability index of the process in the Colombian context was proposed. Diluted acid was the best processing pretreatment, reaching glucose and xylose concentrations of 15.13 g/L, and 12.15 g/L respectively, and a final ethanol concentration of 3.45 g/L. The technical analysis yielded results for Process Mass Intensity (PMI) of 38.14 and Renewable Material Index (RMI) of 5.09. The minimum process scale for economic feasibility (MPSEF) was 19.6 Ton/h. In this sense, the payback period and turnover ratio were 12 years and 35.01%, respectively. Values of 1.85 kg CO2 eq/kg ethanol for carbon footprint and 1.02 m3/kg ethanol for water depletion were also obtained. For the social analysis, the minimum-to-living wage ratio (M/L) was 1.03. Finally, the sustainability index was 75.19%, and the social and environmental values were the most influential aspects affecting the sustainability index. The results of this work allows a novelty vision related to the integral analysis of sustainability for one of Colombia’s native raw materials, and to propose viable solutions for its use, without threatening food security. Graphical Abstract
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