Life cycle assessment of biobutanol production integrated to sugarcane biorefineries in Brazil

摘要: New sugarcane biorefinery routes considering the integral use of biomass have become more important to the strategic objectives of the bioenergy production expansion in Brazil, especially for diversifying and adding value to the sugarcane production chain. Among these new products, biobutanol has been increasingly investigated, mostly for its use as a fuel, since its energy density is greater than that of ethanol, but also to replace an established use as feedstock in the chemical industry. In view of the new green chemistry technological routes development, it becomes interesting and necessary assessing the viability of the butanol production from sugarcane. In this study, the sugarchemical route characterized by the fermentation of sugarcane juice was evaluated using the Life Cycle Asessment method considering arrangements for the process integration in the existing Brazilian sugarcane biorefineries: first and second generation using ABE fermentation (acetone-butanol-ethanol) with wild and genetically modified strains. The evaluation approach took into account the whole production chain, from the agricultural stage, through the transportation of sugarcane and vinasse, to the industrial process of biobutanol production and its use as liquid fuel for transport. The software package SimaPro and the CML 2 Baseline 2000 v2. 05 method were used as tools for the environmental impact assessment. The life cycle inventories were obtained from literature and mass and energy balances taken from process computer simulation. Results showed that butanol produced from the lignocellulosic material (cane bagasse and straw) presents lower …