Techno-Economic and Environmental Analysis of Ethanol Production from 10 Agroindustrial Residues in Colombia

This study evaluates the feasibility of industrial ethanol production from 10 agroindustrial residues in Colombia by considering production yields, profitability, and environmental impacts. For this analysis, sugar cane bagasse, banana stem, corncob, rice husk, sawdust, woodbark, mango wastes, palm residues, pineapple peel, and plantain peel were considered as feedstocks. For each residue, a techno-economic and environmental assessment was carried out using relevant data generated from process modeling. To do this, diluted acid pretreatment and enzymatic hydrolysis (using cellulases) of the lignocellulosic materials were selected as technologies. Besides, Saccharomyces cerevisiae and Pichia stipitis were selected as fermenting microorganisms under normal conditions. The production obtained from process modeling were compared with experimental ones from other authors. Yields between 0.009 and 0.264 kg of ethanol per kg of residue and production costs about $0.65 per liter of ethanol were obtained. Additionally, an average reduction of 39% on environmental impacts was obtained by the use of raw materials. Finally, it was found that four agroindustrial residues show profit margins and profitabilities of 40% over the cost of commercial raw materials in the process of ethanol production.