Biofuels Research Opportunities in Thermochemical Conversion of Biomass

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1 University of Massachusetts Amherst Amherst Conference on Cellulosic Biofuels September 2008 Biofuels Research Opportunities in Thermochemical Conversion of Biomass Douglas Elliott PNL, Follow this and additional works at: Elliott, Douglas, "Biofuels Research Opportunities in Thermochemical Conversion of Biomass" (2008). Conference on Cellulosic Biofuels. 1. Retrieved from This Article is brought to you for free and open access by Amherst. It has been accepted for inclusion in Conference on Cellulosic Biofuels by an authorized administrator of Amherst. For more information, please contact

2 Biofuels Research Opportunities in Thermochemical Conversion of Biomass Presented at the First Annual TIMBR Conference on Cellulosic Biofuels September 19, 2008 Douglas C. Elliott

3 Outline Overview of thermochemical conversion methods Presentation of NSF technology elements Overview of new initiatives

4 Biomass to end use Feedstock Production Feedstock Logistics CONVERSION Biofuels Bioproducts DISTRIBUTION Biofuels rail, truck, pipelines blenders fuel pumps Bioproducts rail, truck END USE Vehicles Chemicals, Materials Demonstration & Deployment Biopower Biopower transmission lines Grid Processing RD&D Feedstock Production and Infrastructure Integrated Biorefineries Biochemical Conversion Thermochemical Conversion Infrastructure

5 Advanced Biomass R&D Sugar Platform Sugar Feedstocks Residues Biomass Combined Heat & Power Fuels, Chemicals, & Materials Integrated Industrial Biorefineries Clean Gas Thermochemical Platform Conditioned Gas or Bio-oils Systems Integration

6 Thermochemical Conversion Unit Operations Feedstock Logistics Biochemical Conversion Combustion Biofuels Distribution Feed Processing and Handling Thermochemical Platform Integration Gasification Pyrolysis Gas Clean-up & Conditioning Bio-oil Stabilization Fuel Synthesis Fuel Synthesis

7 Thermochemical Processing Experience hardwood switchgrass softwood Fast Pyrolysis bubbling fluid bed ( o C) (1 atm) wood bio-oil corn stover bio-oil bagasse bio-oil peat bio-oil Catalytic Hydroprocessing ( o C) ( PSI) Petroleum refinery feedstock DDG&S and stillage manure extracted millfeed and corn fiber biosludge wood Wet Gasification (catalysis, 350 o C) (3000 PSI) Liquefaction ( o C) (3000 PSI) Methane and Carbon dioxide Heavy Fuel Oil Catalytic Hydroprocessing ( o C) (2000 PSI) Refined Oil Products Corn Fiber Wheat Mill Feed Wheat Straw Biosludge Hydrolysis ( o C) ( PSI) Monosaccarides Filterable Biosludge (~90% Waste Reduction) Catalysis/H 2 ( o C) (~2000 PSI) Value Added Products (e.g., polyols)

8 Breaking the Chemical and Engineering Barriers to Lignocellulosic Biofuels Next Generation Hydrocarbon Biorefineries Based on the NSF-led June 25-26, 2007, workshop in Washington, D.C. Over 70 participants from 24 academic institutions, 20 petroleum, chemical and biofuel companies, and 7 national laboratories contributed An Integrated Chemical and Engineering Platform for Overcoming the Barrier to Cellulosic Biofuels...

9 Residence Time of a Reaction versus the Reaction Temperature By selecting a higher temperature process, or adding catalyst, the residence time of chemicals in a reactor can decrease by orders of magnitude.

10 Research Roadmap for Making Lignocellulosic Biofuels Selective thermal processing of lignocellulosic biomass to produce liquid fuels in distributed biorefineries Utilization of petroleum refining technology for conversion of biomassderived oxygenates within existing petroleum refineries Hydrocarbon production by liquid phase processing of sugars to green diesel and jet fuel Process intensification for diesel and gasoline production from synthesis gas from biomass gasification by Fisher-Tropsch synthesis Conceptual design of biorefining processes in conjunction with experimental studies at the beginning of research projects, and Design of recyclable, highly active and selective heterogeneous catalysts for biofuel production using advanced nanotechnology, synthesis methods and quantum chemical calculations.

11 Selective thermal processing of lignocellulosic biomass to produce liquid fuels in distributed biorefineries. Current Status Fast pyrolysis produces high yields of complex bio-oil. (65% thermal efficiency) High-pressure liquefaction, aka, hydrothermal liquefaction produces a more deoxygenated bio-oil. (55% thermal efficiency) In either case, the product requires significant upgrading to become a hydrocarbon fuel. (50% thermal efficiency) High oxygen content limits fuel utilization lower energy content corrosive properties of bio-oil thermal instability of bio-oil

12 Selective thermal processing of lignocellulosic biomass to produce liquid fuels in distributed biorefineries. Concept under development Calibrated Feeder Bubbling Fluid-bed Reactor Char Cyclones Fluidizing Gas Heater Bio-oil Recovery Quenching Spray Towers Cooler System Fast pyrolysis Process variables temperature residence time particle size Substitution of catalyst for fluid-bed material Substitution of active gas for inert fluidizing medium

13 Selective thermal processing of lignocellulosic biomass to produce liquid fuels in distributed biorefineries. Concept under development Biomass kg/hr (db) High pressure pump 330 C 180 bar Preheater/ Reactor 1 Reactor 2 Cooler Cooler Pressure reducer CO 2 Gas /liquid separator gases 1 bar biocrude/ water collection storage storage HTU Biofuel BV

14 Selective thermal processing of lignocellulosic biomass to produce liquid fuels in distributed biorefineries. Overarching Development Needs More detailed thermal deconstruction microkinetic models that can account for a broad range of chemical reactions. Better characterization of the catalytic pathways that occur due to acid generation in the thermal processing and the presence of alkalis Determination of the thermodynamic and physical properties of key chemical species present in thermal processing Analytical techniques that can give chemical speciation

15 Selective thermal processing of lignocellulosic biomass to produce liquid fuels in distributed biorefineries. Specific Development Needs Plant Characteristics that impact Thermal Processing Biomass Feedstock Preprocessing Fractionation and cleanup Catalyst incorporation Torrefaction Bio-Oil Recovery ( Fast Pyrolysis ) Better understand the reactions occurring during bio-oil condensation Improved downstream separation Char separation Bio-oil stabilization Alternative Deconstruction Approaches Alternative solvents to water Elimination of alkalis

16 Utilization of petroleum refining technology for conversion of biomass-derived oxygenates within existing petroleum refineries Development Needs Hydrotreating Processes/Fundamentals Cracking Processes Hydrocracking Processes Fischer-Tropsch Synthesis Future Process Requirements

17 Utilization of petroleum refining technology for conversion of biomass-derived oxygenates within existing petroleum refineries Concept under development H 2 hydrogen recycle light products fast pyrolyzer biomass char cat rxtr medium products heavy products

18 Utilization of petroleum refining technology for conversion of biomass-derived oxygenates within existing petroleum refineries Development Needs Best processes for producing specific transportation fuels, including gasoline, jet fuel, and diesel fuel, need to be determined Types of chemistries and catalysts most effective for deoxygenation of bio-oils in a petroleum refinery C-O bond energy distributions for bio-oils, and identification of which bonds are least stable Detailed analytical characterization Technologies for effective acid removal

19 Hydrocarbon production by liquid phase processing of sugars to green diesel and jet fuel Reaction Classes for Catalytic Conversion of Carbohydrate Derived Feedstocks Hydrolysis Dehydration Isomerization Reforming Carbon-carbon bond coupling Hydrogenation Selective oxidation Hydrogenolysis Aqueous-phase dehydration/hydrogenation

20 Hydrocarbon production by liquid phase processing of sugars to green diesel and jet fuel Advantages of Liquid-Phase Processing The potential to design new generations of nanostructured catalysts Ability to process thermally unstable molecules Reaction control through solvent selection Biphasic reactions Ability to vary ionic strength

21 Hydrocarbon production by liquid phase processing of sugars to green diesel and jet fuel A current process concept

22 Process intensification for diesel and gasoline production from synthesis gas from biomass gasification by Fisher-Tropsch synthesis Current syngas process concepts Water-gas shift CO+H 2 O H 2 + CO 2 Synthetic natural gas CO+3H 2 CH 4 +H 2 O Hydrocarbon fuels XCO+(2X+1)H 2 C x H 2x+2 +XH 2 O gasoline diesel fuel jet turbine fuel Methanol CO+2H 2 CH 3 OH Dimethyl ether 2CO+4H 2 2CH 3 OH CH 3 OCH 3 +H 2 O Mixed alcohols XCO+(2X)H 2 C x H 2x+1 OH+(X-1)H 2 O

23 Process intensification for diesel and gasoline production from synthesis gas from biomass gasification by Fisher-Tropsch synthesis Current technology limitations Biomass conversion to syngas Biomass syngas clean-up Fischer-Tropsch synthesis Mechanisms and the active catalytic sites Methane formation Limitation of chain growth Catalyst deactivation Improvements in product upgrading methodologies Mixed alcohol synthesis Low yield and poor selectivity of the desired alcohol product Operating pressure is not compatible with the operating pressure envisioned for commercial and developmental biomass gasifiers Fuel system and engine hardware for use with dimethyl ether (DME)

24 Process intensification for diesel and gasoline production from synthesis gas from biomass gasification by Fisher-Tropsch synthesis Future research topics Development of more efficient and less expensive biomass gasification processes Better analytical techniques for characterization of low levels of contaminants Improve FTS catalysts and design higher-yield catalysts for ethanol Develop understanding of catalyst deactivation and regeneration Process intensification and catalyst/reactor integration Shaped catalysts and combined catalyst/reactor designs Development and validation of reactor/catalyst models Molecular computation New experimental methodologies

25 Conceptual design of biorefining processes in conjunction with experimental studies at the beginning of research projects High priorities Chemical analytical methods development Physical property information of feeds and products Chemical reaction kinetics Conceptual design methods Life-cycle assessment database Separations

26 Conceptual design of biorefining processes in conjunction with experimental studies at the beginning of research projects Lesser priorities Economic optimization studies Pretreatments Educational materials Hybrid reaction-separations Byproduct & coproduct & markets Robustness & process control Reactor design models Pollution prevention & treatment Cost of promoters, catalysts & solvents

27 Crosscutting scientific issues Analytical database for biomolecules Thermodynamics Chemical reaction engineering Catalyst engineering Catalyst characterization Computational chemistry

28 Recent Solicitation Topics Department of Energy Pyrolysis stabilization of bio-oil University gasification kinetics; improved catalysts for mixed alcohols pyrolysis bio-oil formation fundamentals; coking fundamentals Department of Defense DARPA jet fuel from cellulosic/algae DARPA investigation of catalyst fundamentals in biomass conversion DOE SBIR/STTR Production of Biofuels from Biomass Use of Algae for Fuels Production Department of Agriculture joint with DOE

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