Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbon Fuels and Coproducts: 2018 Biochemical Design Case Update Biochemical Deconstruction and Conversion of Biomass to Fuels and Products via Integrated Biorefinery Pathways Ryan Davis1, Nicholas Grundl1, Ling Tao1, Mary J. Biddy1, Eric C. D. Tan1, Gregg T. Beckham1, David Humbird2, David N. Thompson3, and Mohammad S. Roni3 1 National Renewable Energy Laboratory 2 DWH Process Consulting 3 Idaho National Laboratory NREL is a national laboratory of the U.S. Department of Energy Technical Report Office of Energy Efficiency & Renewable Energy NREL/TP-5100-71949 Operated by the Alliance for Sustainable Energy, LLC November 2018 This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications. Contract No. DE-AC36-08GO28308 Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbon Fuels and Coproducts: 2018 Biochemical Design Case Update Biochemical Deconstruction and Conversion of Biomass to Fuels and Products via Integrated Biorefinery Pathways Ryan Davis1, Nicholas Grundl1, Ling Tao1, Mary J. Biddy1, Eric C. D. Tan1, Gregg T. Beckham1, David Humbird2, David N. Thompson3, and Mohammad S. Roni3 1 National Renewable Energy Laboratory 2 DWH Process Consulting 3 Idaho National Laboratory Suggested Citation Ryan Davis, Nicholas Grundl, Ling Tao, Mary J. Biddy, Eric C.D. Tan, Gregg T. Beckham, David Humbird, David N. Thompson, and Mohammad S. Roni. 2018. Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbon Fuels and Coproducts: 2018 Biochemical Design Case Update: Biochemical Deconstruction and Conversion of Biomass to Fuels and Products via Integrated Biorefinery Pathways. Golden, CO: National Renewable Energy Laboratory. NREL/TP-5100-71949. https://www.nrel.gov/docs/fy19osti/71949.pdf. NREL is a national laboratory of the U.S. Department of Energy Technical Report Office of Energy Efficiency & Renewable Energy NREL/TP-5100-71949 Operated by the Alliance for Sustainable Energy, LLC November 2018 This report is available at no cost from the National Renewable Energy National Renewable Energy Laboratory Laboratory (NREL) at www.nrel.gov/publications. 15013 Denver West Parkway Golden, CO 80401 Contract No. DE-AC36-08GO28308 303-275-3000 • www.nrel.gov NOTICE This work was authored in part by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding provided by U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Bioenergy Technologies Office. The views expressed herein do not necessarily represent the views of the DOE or the U.S. Government. This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications. U.S. Department of Energy (DOE) reports produced after 1991 and a growing number of pre-1991 documents are available free via www.OSTI.gov. Cover Photos by Dennis Schroeder: (clockwise, left to right) NREL 51934, NREL 45897, NREL 42160, NREL 45891, NREL 48097, NREL 46526. NREL prints on paper that contains recycled content. Executive Summary The U.S. Department of Energy (DOE) promotes the production of an array of liquid fuels and bio-derived chemicals from lignocellulosic biomass feedstocks by funding fundamental and applied research that advances the state of technology in biomass collection, conversion, and sustainability. As part of its involvement in this program, the National Renewable Energy Laboratory (NREL) investigates the conceptual production economics of these fuels. Over the past decade, NREL conducted a campaign to quantify the economic implications associated with observed and future targeted performance for the biochemical conversion of corn stover to ethanol through techno-economic modeling. This effort served to set “state of technology” benchmarks and to guide research and development by setting cost targets and tracking progress toward final achievement of these targets in 2012. Beginning in 2013, NREL began transitioning from the singular focus on ethanol to a broad slate of products and conversion pathways, generally focusing on drop-in hydrocarbon fuels or fuel blendstocks, ultimately to establish similar benchmarking and targeting efforts. Several earlier technical reports were released over 2013–2015 documenting initial strategies for achieving interim cost projections based either on biological or catalytic upgrading of lignocellulosic sugars, but with less quantitative focus on longer-term projections for ultimately achieving final hydrocarbon fuel cost goals. This report serves as an update to the biological sugar conversion approach, reflecting modifications to underlying conversion operational strategies, as well as refinements to the techno-economic model details. In addition, the report includes a more quantitative focus on envisioned processing requirements for achieving final fuel cost goals moving further into the future, via inclusion of value-added coproducts. The overarching process designs evaluated here convert biomass to diesel- and naphtha-range fuels using alkaline and mechanical refining pretreatment, enzymatic saccharification, biological (fermentative) conversion of hydrolysate sugars to intermediate fuel precursors, and catalytic upgrading of those intermediates to final fuel products. Additionally, value-added coproducts— represented by adipic acid as a proof-of-concept example—are produced by the deconstruction and upgrading of lignin and other biomass residual components through a similar sequential biological and catalytic processing train. Ancillary areas—feed handling, hydrolysate processing, wastewater treatment, residual waste combustion, and utilities—are also included in the design. Broadly, the fuel production processes considered in this report are based on two example anaerobic pathway classes for bioconversion of hydrolysate sugars to hydrocarbon fuel intermediates, namely short-chain carboxylic acids and 2,3-butanediol (BDO), followed by catalytic upgrading steps to remove oxygen and undergo condensation/oligomerization reactions to produce longer-chain hydrocarbon fuel blendstocks. Aerobic bioconversion pathways to fuel components (e.g., lipid/fatty acid pathways) are not included in this design case, given more challenging design and economic constraints for such pathways in ultimately being able to achieve the required cost targets (on the order of roughly $2/gallon gasoline equivalent (GGE) cost premiums previously estimated for aerobic versus anaerobic options). Detailed material and energy balances and capital and operating costs for this baseline process are also documented. This techno-economic analysis models a production cost for cellulosic hydrocarbon biofuels that can be considered as a baseline to assess the competitiveness and market potential for the technology. It can also be used to quantify the economic impact of individual conversion iii This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications. performance targets and prioritize them in terms of their potential to reduce cost. The analysis presented here also includes consideration of key environmental sustainability implications of the modeled biorefineries by tracking sustainability metric indicators such as carbon yields, primary energy import demands (natural gas and power imports), and water consumption attributed to the conversion process models. Additionally, an accounting of energy balances is provided, to quantify the energy output allocations across the biorefinery. Building on prior design report practices, NREL, supported by subcontractor DWH Process Consulting, performed a feasibility-level analysis for a plausible integrated biorefinery conversion process to meet the ultimate DOE fuel selling price goal of $2.50/GGE or less by the year 2030. The modeled biorefinery processes 2,205 dry tons biomass per day at a target price of $71.26/dry ton (delivered to the pretreatment reactor throat) and achieves a fuel selling price of $2.49/GGE for the “acids” pathway or $2.47/GGE for the “BDO” pathway to fuels (2016 U.S. dollars) as determined by modeled conversion targets and “nth-plant” project costs and financing. These fuel price estimates are attributed to a total fuel yield of 44.8 and 43.2 GGE/dry ton for the acids and BDO pathways, respectively, as well as a final adipic acid coproduct yield of 259 and 266 lb/dry ton for the respective cases, with an adipic acid market value of $0.86/lb. Additionally, given substantial demands for caustic (sodium hydroxide) and acid usage throughout the integrated process at considerable costs, this work highlights the need for either recovering and reusing these chemicals through advanced separations technologies, or otherwise offsetting a portion of those costs through the sale of the resultant sodium sulfate byproduct. The latter is reflected in this report, generating a smaller co-product revenue stream for sale of this salt at $0.07/lb, beyond the purposeful co-production of adipic acid. All modeled fuel prices are also based on underlying financial assumptions including 10% internal rate of return, 40% equity financing (60% debt financing at 8% interest), and 30-year plant lifetime. Both pathways exhibit high sensitivity to yields across the fuel production trains, but even more strongly to