Techno-economic analysis of two bio-oil upgrading pathways

We evaluate the economic feasibility for two bio-oil upgrading pathways: two-stage hydrotreating followed by fluid catalytic cracking (FCC) or single-stage hydrotreating followed by hydrocracking. In the hydrotreating/FCC pathway, two options are available as the hydrogen source for hydrotreating: merchant hydrogen or hydrogen from natural gas reforming. The primary products of the hydrotreating/FCC pathway are commodity chemicals whereas the primary products for the hydrotreating/hydrocracking pathway are transportation fuels and hydrogen. The two pathways are modeled using Aspen Plus® for a 2000 metric tons/day facility. Equipment sizing and cost calculations are based on Aspen Economic Evaluation® software.The bio-oil yield via fast pyrolysis is assumed to be 65% of biomass. We calculate the internal rate of return (IRR) for each pathway as a function of feedstock cost, fixed capital investment (FCI), hydrogen and catalyst costs, and facility revenues. The results show that a facility employing the hydrotreating/FCC pathway with hydrogen production via natural gas reforming option generates the highest IRR of 13.3%. Sensitivity analysis demonstrates that product yield, FCI, and biomass cost have the greatest impacts on facility IRR. Monte-Carlo analysis shows that two-stage hydrotreating and FCC of the aqueous phase bio-oil with hydrogen produced via natural gas reforming has a relatively low risk for project investment.

Generalized process diagram for bio-oil production and upgrading.Figure optionsDownload as PowerPoint slideHighlights
► Two bio-oil upgrading pathways are investigated.
► Product yield, fixed capital cost, and biomass cost strongly affect facility IRR.
► Investment for commodity chemicals production is of low risk.