Environmental life cycle assessment of lignocellulosic ethanol-blended fuels: A case study

After the implementation of a biofuel target in 2017, China, the second largest consumer of oil in the world, accelerated the development of lignocellulosic biomass technology to produce ethanol and minimized food security risks commonly associated with first generation biofuel production. In this study, Life Cycle Assessment (LCA) is used to investigate three new lignocellulosic biomass refinery systems based on corncob which co-produce ethanol with chemicals and energy. The bioethanol is used in E10 and E85 biofuel mixes and these are compared with a fossil gasoline reference system. Using 1 km distance driven by a compact size flexible fuel passenger vehicle as the functional unit and a exergy allocation approach to the raw material inputs and to the co-products in the simulated multifunctional biorefinery processes, the results indicate that regardless of the configuration of the ethanol-biorefinery, ethanol-blended fuels performed better than gasoline in terms of fossil fuels depletion (E10 6% lower; E85 64-70% lower), global warming potential (E101-10% lower; E85 5-113% lower) and human toxicity potential (E10 6-7% lower; E85 72-75% lower), but worst in terms of ozone layer depletion (E10 4.5-6.8 times higher; E85 51.9-78.2 times higher), acidification (E10 30-50% higher; E85 3.3-5.5 times higher) and eutrophication potential (E10 5.2-7.0 times higher; E85 42.4-64.0 times higher) than gasoline. (C) 2019 Elsevier Ltd. All rights reserved.