Life-cycle assessment of alternative pyrolysis-based transport fuels

Subtitle:implications of upgrading technology, scale, and hydrogen requirement

Bio-oil produced from fast pyrolysis of biomass is a promising substitute for crude oil that can meet climate change mitigation goals, but due to its high oxygen content, it requires upgrading to remove oxygen in order to be used as a transportation fuel. Hydrodeoxygenation (HDO) is one means of upgrading fast pyrolysis oil; however, its main limitation is its large hydrogen requirement. We evaluate an alternative electrochemical deoxygenation (EDOx) method that uses catalytic electrode membranes on a ceramic, oxygen-permeable support to generate hydrogen in situ for deoxygenation at the cathode and oxygen removal at the anode. We analyze the life-cycle greenhouse gas (GHG) emissions and scale effects of gas-phase upgrading of pyrolysis oil [300 t/day (MTPD)] using different configurations of EDOx and compare it with the large-scale HDO process (2000 MTPD). We observe that the EDOx configurations have lower total GHG emissions of 58.4 and 7.411 g of CO2 equiv/MJ for vehicles operated with diesel and gasoline, respectively, compared to HDO (39 g of CO2 equiv/MJ). Furthermore, the EDOx processes offers potentially 10 times more small-scale pyrolysis upgrading facilities in the United States compared to HDO, suggesting that small-scale on-site EDOx processes can reach more inaccessible forest biomass resources.

Publication year:2018

Keywords:A1 Journal article

BOF-keylabel:yes

BOF-publication weight:10

CSS-citation score:1

Authors:International

Authors from:Higher Education

Accessibility:Open