Pilot-Scale Thermochemical Technologies for Integrated Biorefinery Development The Thermochemical Conversion Platform

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1 Pilot-Scale Thermochemical Technologies for Integrated Biorefinery Development The Thermochemical Conversion Platform David C. Dayton, Thermochemical Platform Area Leader National Renewable Energy Laboratory National Bioenergy Center Golden, CO USA IEA Bioenergy Executive Committee Meeting April 25-27, 27 Golden, CO USA 1 The President s Biofuels Initiative The 3x3 Vision High Yield Growth With Energy Crops High Yield Growth Without Energy Crops Existing & Unexploited Resources Forest Resources Total Grains & Manure Sub-Total Ag Residues (non Energy Crops) Perennial (Energy) Crops Transformation through Intermediates (sugars) Reduction to to building blocks (CO, H 2 ) Biochemical conversion main difference is in the primary catalysis system Thermochemical conversion Million Tons Annually Actual Volumes (Billion gal/yr) 15 Thermochemically Derived Biochemically Derived Grain Derived 3% 24 Gasoline Energy Equivalent from Ethanol 5 Existing & High Yield High Yield 24 Motor Unexploited Growth But No Growth With Gasoline Resources Energy Crops Energy Crops

2 Opportunities for Thermochemical Biofuels Near-term - gasification/mixed alcohol synthesis for $1.7 by 212 Cost-competitive with High Potential Biofuel Yields Mid-term (3x3) Biorefinery residues in integrated BC/TC plants Pyrolysis Long-term (3x3) Selective Thermal Transformation (improve yields and selectivity) Challenge: Develop thermochemical technologies that are technically and economically feasible at the appropriate scale for reasonably available biomass resources Mixed Alcohols i-c 4 NH 3 Alkali-doped ZnO/Cr 2O3 Cu/ZnO; Cu/ZnO/Al 2O3 CuO/CoO/Al 2O3 MoS 2 Isosynthesis ThO 2 or ZrO 2 N 2 over Fe/FeO H 2 O WGS Purify (K 2 O, Al 2 O 3, CaO) Waxes Diesel Fischer-Tropsch Syngas CO + H 2 H 2 Fe, Co, Ru HCo(CO) 4 HCo(CO) 3P(Bu 3) Rh(CO)(PPh 3) 3 Olefins Gasoline Oxosynthesis Formaldehyde Co, Rh Aldehydes Alcohols Ag Cu/ZnO Products from Syngas Co homologation Ethanol MTBE isobutylene acidic ion exchange Methanol Al 2 O 3 DME Direct Use carbonylation CH 3 OH + CO Acetic Acid Co, Rh, Ni zeolites MTO MTG M M85 DMFC Olefins Gasoline

3 Mixed Alcohol Design Report Thermochemical Ethanol via Indirect Gasification and Mixed Alcohol Synthesis of Lignocellulosic Biomass (PDF 3.3 MB) NREL-TP Targeted to appropriate feedstock, level of technologies, and market conditions to provide a benchmark thermochemical process for achieving $1.7/gal ethanol by 212 Feedstocks Forest resources as primary feedstock Base design using wood composition Scenarios for alternate feedstocks Costs consistent with forest resources per Billion Ton Study $35 per bone dry ton at plant gate Scenarios for other feedstock costs, moisture content, ash content, Integration & Economic Issues Economic Mixed C3OH+ by-product Final separation of C3OH+ mixture done over the fence line Scenarios for alternate C3OH+ values Fraction of chemical feedstock value (target case) Equivalent to ethanol Kerosene value (fraction of gasoline value) Scenarios 25 Dollars Total Project Investment Average Installation Factors Contingency Return on Investment Loan vs. Equity Financing Additional Fossil Fuel fossil fuel for energy deficiency Conversion Technologies Indirect gasification BCL correlations with decreased methane production Scenarios Costs of catalyst impregnated olivine Gasifier temperature Yields: hydrocarbon, CO2, char, Cleanup & Conditioning Tar reforming consistent with goal case Includes on-line catalyst regeneration Scenarios Reforming conversions Catalyst lifetime Reformer costs (non catalysts) Acid removal costs Catalytic fuel synthesis Specified conversions Kinetic calculations done off line High single pass conversions Scenarios Single pass yields Selectivity to ethanol Alcohol distribution Catalyst lifetime Catalyst specs (sulfur & CO 2 allowability)

4 Technical Barrier Areas Gas Cleanup & Conditioning has the largest economic impact January 9-1, 27 in Washington, DC, 7 Attendees from Industry, Academia, Government, Size Reduction Storage & Handling De-watering Drying Feedstock Interface Products Ethanol Gasification Gas Cleanup & Conditioning Fuel Synthesis Thermal Efficiency Carbon Conversion Ash Chemistry Pressure Steam/Oxygen Particulate removal Catalytic Reforming Tars Light Hydrocarbons Methane S, N, Cl mitigation CO 2 removal H 2 /CO adjustment By-products Methanol n-propanol n-butanol n-pentanol Separations Recycle Selectivity Targets Minimum Ethanol Selling Price Minimum Ethanol Selling Price ($ per gallon) $2.5 $2. $1.5 $1. $.5 Forest Resources 56 gal/ton State of Technology Estimates Conversion Feedstock Previous DOE Cost Targets President's Initiative Costs in 22 Dollars Forest & Ag Resources 89 gal/ton mixed alcohols* $

5 Gasification R&D for $1.7 Thermochemical Ethanol Targets Gas Cleanup and Conditioning Tar Reforming Catalyst Development Consolidated tar and light hydrocarbon reforming to reduce capital and operating costs Tar Reformer Performance - % Conversion Compound Current Goal Methane (CH 4 ) Ethane (C 2 H 6 ) Ethene (C 2 H 4 ) Tars (C1+) (C 6 H 6 ) Ammonia (NH 3 ) Advanced Catalysts and Process Improvements for Mixed Alcohol Synthesis Increase single pass conversion efficiency (38.5% to 5%) Improve selectivity (8% to 9%) Improve yields at lower synthesis pressure Fundamental Gasification Studies Technical validation of comparable syngas quality from biorefinery residues and wood residues 2% 9% 5% 95% 7% 7% 8% 99% 99% 99.9% 99% 9% Core Expertise to Address Barriers Thermochemical Analysis Conceptual integrated thermochem/biochem process Detailed stand-alone thermochemical process Thermochemical Conversion Feedstock dependent performance and syngas quality Gas Clean-Up & Conditioning Fluidizable tar reforming catalyst evaluation for IBR applications Catalyst regeneration for maximizing catalyst performance and lifetime Integration of Operations Reforming catalyst performance integrated with gasifier operations to consolidate unit operations for capital cost reductions

6 Thermochemical PDU Gasification feed dependent Pilot-scale syngas Biomass Thermochemical Conversion quality, reforming catalyst performance Pyrolysis medium quantity oil production, gas and liquid solids filtration, real time product optimization Gas Clean-Up and Conditioning Integrated tar reforming - catalyst lifetime & deactivation kinetics On-line tar and product analysis MBMS - Acetylene and Tertiary Tars Concentration (mg/nm 3 - wet) Acetylene Naphthalene Phen/Anthr 12: 14: 16: 18: 2: 22: : 5/2/25 MBMS Tar Sampling Advantages Universal detection (low and high molecular weight species) Real-time monitoring Preserves reactive and condensable species Rapid screening/fingerprinting Large dynamic range (1 6 to 1-1 ppmv) High-pressure, high-temperature system monitoring Typical Hydrocarbons/Tars Observed Molecular Weight Formula Chemical Name(s) 15,16 CH 4 methane 26 C 2 H 2 acetylene 78 C 6 H 6 benzene 91,92 C 7 H 8 toluene 94 C 6 H 6 O phenol 14 C 8 H 8 styrene 16 C 8 H 1 (m-, o-, p-) xylene 18 C 7 H 8 O (m-, o-, p-) cresol 116 C 9 H 8 indene 118 C 9 H 1 indan 128 C 1 H 8 naphthalene 142 C 11 H 1 (1-, 2-) methylnaphthalene 152 C 12 H 8 acenapthylene 154 C 12 H 1 acenaphthene 166 C 13 H 1 fluorene 178 C 14 H 1 anthracene, phenanthrene 192 C 15 H 12 (methyl-) anthracenes/phenanthrenes 22 C 16 H 1 pyrene/fluoranthene 216 C 17 H 12 methylpyrenes/benzofluorenes 228 C 18 H 12 chrysene, benz[a]anthracene, 242 C 19 H 14 methylchrysenes, methylbenz[a]anthracenes 252 C 2 H 12 perylene, benzo[a]pyrene, C 21 H 14 dibenz[a,kl]anthracene, 278 C 22 H 14 dibenz[a,h]anthracene,

7 On-line Analytical Capabilities Non-dispersive infrared (NDIR) Analyzer for CH 4 (range: -5 vol%) NDIR Analyzers for CO 2 and CO (-5 vol% range) Paramagnetic Oxygen Analyzer (range of -25 vol%) H 2 thermal conductivity analyzer (range of -5 vol% and analog inputs for %CO, %CH 4 and %CO 2 to correct the H 2 value) Quad Micro Gas Chromatograph 4 channel, on-line GC with 2-3 min cycle time H 2, O 2, N 2, CH 4, CO, CO 2, C 2 H 6, C 2 H 4, C 2 H 2, C 3 H 8, and C 4 paraffin's and olefins Transportable molecular beam mass spectrometer (TMBMS) Continuous, real-time monitoring of all gas phase products withparticular emphasis on condensible tars and heteroatoms NREL 15 kwt Thermochemical Process Development Unit

8 Real-time data from corn stover gasification 9 Process Data Trends Temperature (ºC) Average TC Temp Bed Temp (6.5") Bed Temp (17") Bed Temp (27.5") Corn Stover Steam Nitrogen Feedrate (kg/hr) GC Gas Composition 6 12: 16: 2: : 5/2/25 vol % - dry, N 2 Free Methane Ethylene Acetylene Propene 1-Butene 2 12: 14: 16: 18: 2: 22: : 5/2/25 On-line Tar Measurements MBMS - Acetylene and Tertiary Tars Concentration (mg/nm 3 - wet) Acetylene Naphthalene Phen/Anthr 12: 14: 16: 18: 2: 22: : 5/2/25 Concentration (mg/nm 3,wet) MBMS - and Secondary Tars Toluene Phenol Cresols (o, m, p) 2 12: 14: 16: 18: 2: 22: : 5/2/25

9 Feedstock Fuel Variability Feedstock Composition Wood Corn Stover BioChem Residue NREL TCPDU Syngas Composition (S/B = 1) Proximate Analysis (wt %) Moisture (63.76) Vol% Wood Corn Stover BioChem Residue Ash H ? Volatiles CO ? Fixed C CO ? Ultimate Analysis (wt%) CH ? C C 2 H ? H N (mg/nm 3 ) 6,5 1,? O S NREL Catalyst Development Objective: Long duration catalyst activity to maintain syngas quality (tar destruction >99%) to meet accepted gas quality standards Performance requirements Tar reforming: CxHyOz + H 2 O(g)? H 2 + xco Water gas shift: H 2 O + CO? CO 2 + H 2 Coke gasification: C + H 2 O(g)? COx + H 2 Steam methane reforming: CH 4 + H 2 O? CO + 3H 2 Improve reforming catalyst performance Develop attrition resistant reforming catalysts Support type/treatment/particle size/surface area Optimize catalyst regeneration Characterize and understand catalyst behavior Catalyst components and promoters Understand/minimize catalyst deactivation Predict pilot scale behavior from MATS behavior Preparation Incipient wetness Calcination Reduction

10 Tar Reforming: Micro Pilot Scale Evaluation MATS 1* Fixed bed 1 g catalyst TPR* characterization TCPDU-FSR* Fluid bed 5 kg catalyst Process data Kinetic data Lifetime data Online analysis Rapid catalyst preparation 2 FBR* Fluid bed 25 g catalyst Kinetic data Lifetime data TCPDU slipstream Online analysis MATS 2 Fixed bed 1 g catalyst Tar destruction Steam reforming TCPDU slipstream MATS: Microactivity test system FBR: Fluidized bed reactor FSR: Full stream reformer TCPDU: Thermochemical process development unit TPR: Temperature programmed reaction S Deactivation of Ni/Al 2 O 3 Catalysts S blocks Ni active sites and eliminates sites for H 2 adsorption and HC cracking Ni Ni Little S adsorption on a-alumina S Surface-mediated mechanism Ni Ni HT oxidation causes S to penetrate catalyst surface S removal depends on temperature and steam content Current research to achieve regeneration at process conditions

11 Catalyst Deactivation by H 2 S C 2 H 4 Flow 15 sccm 9 [H 2 S] Temp ºC S/C Bed Height Catalyst [H 2 S] ppmv C 2 H 4 Conversion % Pre Deact. 1- ppmv GHSV 9, h -1 t res.3 s 18 mm 32 C 2 H 4 Conversion % Post Deact. % Ethylene Conversion Cat 32 ppm Comm Cat ppm C 2 H 4 Conversion % Post Regen. Time (h) Cat 32 1 ppm H2S Cat 32 5 ppm Cat 32 2 ppm Cat 32 5 ppm >9 Time on stream (TOS) Regeneration time > > >95 Tar Cracking Catalyst Evaluation Technical Goals Deactivation kinetics; Steady-state conversion efficiency Bench and pilot-scale efforts aligned to determine optimized reforming catalyst performance Provide technical data for design of regenerating tar reforming reactor and refined technoeconomic analyses % Conversion Initial NREL 23 Catalyst Deactivation Wood syngas, Medium space velocity, 825ºC Toluene Phenol Naphthalene Phen/Anth Time on Stream (minutes) % Conversion Initial NREL 23 Catalyst Deactivation Corn Stover syngas, Low space velocity, 875ºC Time on Stream (minutes) Toluene Phenol Naphthalene Phen/Anth

12 Illustration by Oak Ridge National Lab