Techno-economic analysis of product biorefineries utilizing sugarcane lignocelluloses: Xylitol, citric acid and glutamic acid scenarios annexed to sugar mills with electricity co-production

The profitability of biorefinery scenarios utilizing sugarcane lignocellulose (bagasse and harvesting residues), annexed to an existing sugar mill for the co-production of electricity and bioproducts was investigated. Biorefinery scenarios for xylitol, citric acid or glutamic acid production, each in combination with electricity, were simulated in Aspen Plus (R) to generate mass and energy balances, and perform economic analyses. The profitability was compared to a combined heat and power (CHP) plant baseline scenario that solely combusts biomass for electricity co-production. Scenario 2, citric acid and electricity co-production was not profitable at a selling price of 680 $/t citric acid. However Scenario 1, xylitol and electricity co-production, and Scenario 3 for glutamic acid and electricity co-production, both demonstrated economic feasibility with IRR's of 12.3% and 31.5% for a selling price of 3000 $/t and 3625 $/t, respectively. These IRR values exceeded the baseline CHP plant IRR of 10.3% and hurdle rate of 9.7%.