Alternatives to produce biorefinery products from sugarcane bagasse

CLAUSER, NICOLÁS; SOLEDAD GUTIERREZ; MARÍA CRISTINA AREA; FERNANDO ESTEBAN FELISSIA; MARÍA EVANGELINA VALLEJOS

Conferencia; CIADICYP 2016; 2016

The production processes of bioproducts and biofuels from lignocellulosic biomass can be designed at different scales (micro, small, medium and large). Some advantages of small-scale biorefineries are lower capital and logistics costs, and lower inversion risk than those in large-scale ones, in addition to the possibility of labor occupation in rural areas. In this work, different products from hemicelluloses and residual solid of the autohydrolysis of sugarcane bagasse were studied to find the most feasible scenario for a small-scale biorefineries. In fist scenery, the production of xylose syrup, furfural and xylitol from hemicelluloses in the spent liquor of sugarcane bagasse autohydrolysis (15,000 ton per year of bagasse) as well as energy generation and medium-density fibreboard (MDF) production from the residual solid were evaluated. The IRR values for this scenery showed that the production of xylose syrup and MDF are the most profitable alternative due to lower capital investment. The second alternative is furfural with MDF production. The IRR of xylitol production is relatively low due to the high investment cost (despite of the high price of this product). Second scenery was proposed to improve the feasibility of xylitol production. Liquid-solid ratio of the autohydrolysis treatment was reduce from 7:1 to 5.5:1 which mean a reduction in energy consumption of 23% respect to first scenery. In this condition, the production of xylitol and energy generation (EG), MDF, ethanol or pellets from the residual solid was evaluated (Table 1). In scenery I results show that is necessary to optimize the involved processes, e.g., autohydrolysis, evaporation, delignification, and purification, which present high-energy consumption. In scenery II a marked improvement in the IRR was due to the decrease in the pretreatment liquid-solid ratio. Another alternatives to improve the IRR are: i) increasing the production scale (70,000-100,000 ton year-1), because the capital cost per unit of output decreases as plant capacity increases; ii) the use of lignin as high value-added products, e.g., for antioxidants, resins, and adhesives.