Large-scale biohydrogen production from bio-oil

Large amount of hydrogen is consumed during the upgrading of bitumen into synthetic crude oil (SCO), and this hydrogen is exclusively produced from natural gas in Western Canada. Because of large amount of emission from natural gas, alternative sources for hydrogen fuel especially renewable feedstocks could significantly reduce CO2 emissions. In this study, biomass is converted to bio-oil by fast pyrolysis. This bio-oil is steam reformed near bitumen upgrading plant for producing hydrogen fuel. A techno-economic model is developed to estimate the cost of hydrogen from biomass through the pathway of fast pyrolysis. Three different feedstocks including whole-tree biomass, forest residues (i.e. limbs, branches, and tops of tree produced during logging operations), and straw (mostly from wheat and barley crops) are considered for biohydrogen production. Delivered cost of biohydrogen from whole-tree-based biomass ($2.40/kg of H2) is lower than that of forest residues ($3.00/kg of H2) and agricultural residues ($4.55/kg of H2) at a plant capacity of 2000 dry tonnes/day. In this study, bio-oil is produced in the field/forest and transported to a distance of 500 km from the centralized remote bio-oil production plant to bitumen upgrading plant. Feedstock delivery cost and capital cost are the largest cost contributors to the bio-oil production cost, while more than 50% of the cost of biohydrogen production is contributed by bio-oil production and transportation. Carbon credits of $133, $214, and $356/tonne of CO2 equivalent could make whole-tree, forest residues, and straw-based biohydrogen production competitive with natural gas-based H2 for a natural gas price of $5/GJ, respectively.