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Printed on paper containing at least 50% wastepaper, including 10% post consumer waste.iii ForewordThe purpose of this techno-economic analysis is to determine the economics of converting biomass to transportation fuel components via fast pyrolysis. Every effort has been made to place this analysis on an equivalent basis with other biomass conversion technologies analyzed in separate reports by using common assumptions. The process design and parameter value choices underlying this analysis are exclusively based on public domain literature. Accordingly, the results should not be interpreted as optimal performance of mature technology, but as the most likely performance given the current state of public knowledge. Executive SummaryThe purpose of this study is to develop techno-economic models for assessment of the conversion of biomass to valuable fuel products via fast pyrolysis and bio-oil upgrading. Liquefaction of biomass by fast pyrolysis and subsequent upgrading of the resulting pyrolysis oil (bio-oil) by hydrotreating and hydrocracking-refinery processes that use hydrogen to remove impurities and break large molecules down to smaller ones-is a promising means for producing renewable transportation fuel. The upgrading process assessed in this study produces a mixture of naphtha-range (gasoline blend stock) and diesel-range (diesel blend stock) products. This study develops techno-economic models and uses them to analyze the economics of two scenarios. In one, hydrogen needed for the upgrade process is produced onsite by reforming biooil. In the other, the hydrogen is purchased from an outside source.Both scenarios are based on a fast pyrolysis plant with bio-oil upgrading using 2,000 metric tons per day (MT/day) of corn stover feedstock. Major assumptions made for this analysis match those of companion analyses for producing transportation fuel from biomass via biochemical and gasification technologies. Product value-defined as the value of the product needed for a net present value of zero with a 10% internal rate of return-is first calculated for a mature industry or n th plant and then adjusted for a pioneer plant or one of the first of its kind.The study results indicate that petroleum fractions in the naphtha distillation range and in the diesel distillation range are produced from corn stover at a product value of $3.09/gal ($0.82/liter) with onsite hydrogen production or $2.11/gal ($0.56/liter) with hydrogen purchase. These values correspond to a $0.83/gal ($0.21/liter) cost to produce the bio-oil. Based on these n th plant numbers, product value for a pioneer hydrogen-producing plant is about $6.55/gal ($1.73/liter) and for a pioneer hydrogen-purchasing plant is about $3.41/ gal ($0.92/liter). Although these results suggest that pyrolysis-derived biofuels are competitive with other alternative fuels, the technology is relatively immature, resulting in a high level of uncertainty in these estimates.Capital costs for integrated hydrogen production are estimated at $287 million with a fuel yield of 35...

The U.S. biomass initiative is counting on lignocellulosic conversion to boost the quantities of biofuels currently produced from starches in order to achieve much needed energy security in the future. However, with current challenges in fermentation of lignocellulosic material to ethanol, other methods of converting biomass to usable energy have received consideration nationally. One thermochemical technique, fast pyrolysis, is being considered by the Agricultural Research Service (ARS) researchers of the USDA for processing energy crops such as switchgrass and other agricultural residues, e.g., barley hulls and alfalfa stems for bio-oil (pyrolysis oil or pyrolysis liquids) production. A 2.5 kg/h biomass fast pyrolyzer has been developed at ARS and tested for switchgrass conversion. The unit has provided useful data such as energy requirements and product yields that can be used as design parameters for larger systems based on the processing of perennial energy crops. Bio-oil yields greater than 60% by mass have been demonstrated for switchgrass, with energy conversion efficiencies ranging from 52 to 81%. The results show that char yielded would suffice in providing all the energy required for the endothermic pyrolysis reaction process. The composition of the noncondensable gas produced has been initially characterized. Initial mass and energy balances have been calculated based on this system, yielding useful parameters for future economic and design studies.

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