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Distributed Fast Pyrolysis for Conversion of Biomass to Stable Refinable Crude Bio‐oils
Charles A. MullenAkwasi A. Boateng
The Science and Engineering for a Biobased Industry
Wyndmoor, PA
August 3, 2010
Biomass Conversion Pathways
Soil Amendment/Solid Fuel
F-T LiquidsH2
SYNGASH2 + CO
Biomass Pyrolysis Bio-oil
Bio-charLiquid Fuels/Chemicals
Sugars
Lignin
EthanolBiochemicalConversion
ThermochemicalConversion
Fermentation
Pyrolysis• Defined as the heating of organic material in the absence of
air• Biomass Pyrolysis Produces Bio‐oil, Bio‐char, and Syngas
• Slow Pyrolysis– Slow Heating Rates– Temperatures 300 – 500 °C – Maximizes Bio‐char Production
• Fast pyrolysis – High heating (& cooling) Rates– Temperatures 450 – 500 °C– Maximizes Bio‐oil Production
Fast Pyrolysis at ERRC: CRIS ‐082Goals
• Bring fast pyrolysis closer to commercialization
• In‐situ stabilization for predictable product
• In‐situ upgrading to reduce downstream upgrading, amenable to existing refineries – “drop‐in”
• Make the bio‐char a soil‐amendable product
Advantages of Fast Pyrolysis
• Amenable to small scale• On‐Farm Scale Advantage• Energy density• Less energy intensive• Relatively simpler system design• Oxygenated liquid bio‐crude
– up‐gradable to drop in diesel, gasoine and jet‐fuels
• Infrastructure exists for its refining• Charcoal vision
– Carbon Sequestration
Vision for Distributed Processing
Carbon Cycle for Fast PyrolysisSoy Straw Example
B
Major Barriers to Commercialization of Bio‐oil as 2nd Generation Bio‐fuel
High O‐Content High Water Content Acidity: pH ~ 2.5 (corrosive) Stability: Unstable – Over time, oligimerization and
condensation reactions increase average MW, viscosity, and water content
Storage & Piping Problems Heterogeneity makes it unsuitable for diesel engines “as
is” Needs stabilization, upgrading before use in existing
refineries
• Quantify the effect of various agricultural feedstockson the pyrolysis process efficiency, kinetics, product yield and composition.
• Develop commercially preferred catalytic and non‐catalytic processes for distributed on‐farm scale production of stable and easily upgradable bio‐oil
• Technologies for in‐situ or ex‐situ activation of bio‐char to produce a soil‐amendment grade product
Fast Pyrolysis at ERRC: CRIS ‐082Research Objectives
Fluidized Bed Pyrolysis System
Pyrolysis Conditions
Biomass Agricultural Feedstocks
Fluidized‐Bed Material Silica Sand
Particle Size (Bed Material) ‐20 +25 mesh
Fluidizing Gas N2
Gas Flow Rate 1.0 – 1.5 kg/hr
Min. Fluidization Velocity 0.23 m/s
Superficial Velocity 0.65 m/s
Biomass Feed Rate 1.5‐3.5 kg/h
Biomass:N2 Ratio 0.46
Feed Mean Particle Size ~2 mm
Bed Pressure 4 kPa
Bed Temperature 480 – 505 °CCondenser #1 Temperature 200‐245 °CCondenser #4 Temperature 45‐65 °CESP Temperature 25‐45 °CHeat Rate ~4500 °C/sTotal Quench Rate 50‐60 ‐°C/s
Fast Pyrolysis Product Yields
0
10
20
30
40
50
60
70
80%
Yie
ld
Bio-oil Charcoal Non-Condensable Gas
Woods Grasses LegumesAg. and BiofuelsCoproducts
Carbon Conversion
0
10
20
30
40
50
60
70
80
90
% F
eeds
otck
Car
bon
Bio-oil Charcoal Non-Condensable Gas
Woods Grasses LegumesAg. and BiofuelsCoproducts
ARSOak
Chicken Litter Guayule
Barley Straw
Corn Stover
Rye-grass
Switch-grass
Alfalfastems
Soybean straw
ESP Fraction % Water 8.2 9.8 1.7 6.6 5.9 8.2 6.2 8.2 8.9Condenser Fraction % Water 29.0 30.0 N/A 35.6 15.5 33.5 23.0 42.8 31.8Total % Water 22.3 20.1 1.7 26.7 9.2 21.3 15.8 28.6 21.4Organic C:O Ratio 1.46:1 2.53:1 3.27:1 1.16:1 1.49:1 1.0:1 1.35:1 1.82:1 1.15:1HHV (MJ/kg), wet 17.9 25.3 30.4 19.3 19.5 20.3 19.9 23.7 20.9HHV (MJ/lkg), dry 23.0 31.6 30.9 26.3 26.2 25.7 23.6 33.1 25.6
pH 2.6 6.9 ‐‐ 2.4 2.9 2.8 3.1 2.9
Bio‐oil Analysis
ARS Oak
Chicken Litter
Guayule Bagasse
Barley Straw
Corn Stover
Ryegrass
Switchgrass
Alfalfa Stems
1H NMR of Bio‐oils
Woods
AnnualGrasses
Perennial Grass
Legume
400 MHz,Acetone-d6
Mullen, C. A., Strahan, G. D., Boateng, A. A. Energy Fuels, 2009, 23, 2707.
13C NMR of Bio‐oils
Mullen, C. A., Strahan, G. D., Boateng, A. A. Energy Fuels, 2009, 23, 2707.
ARS Oak
Chicken Litter
Guayule
Barley Straw
Corn Stover
Rye-grass
Switch-grass
Alfalfa
Woods
AnnualGrasses
Perennial Grass
Legume
100 MHz,Acetone-d6
Some Bio‐oil ComponentsGC/MS & HPLC
Compounds(wt%)
ARSOak
Chicken Litter Guayule Barley
StrawCorn
StoverSwitch-grass
Alfalfa Stems
Soybean Straw
Acetic Acid 11.1 0.70 3.09 8.56 6.26 2.94 3.49 5.74
Furfural ‐‐ ‐‐ ‐‐ 0.39 0.71 0.62 ‐‐ 0.56
Hydroxyacet‐aldehyde 1.3 ‐‐ ‐‐ ‐‐ 4.00 2.40 ‐‐ 0.82
Acetol 4.95 0.05 0.73 6.31 7.08 0.78 0.78 9.56
Levoglucosan 3.00 0.23 1.37 2.06 12.36 6.38 0.14 7.75
Guaiacol 0.25 0.35 0.39 0.25 0.25 0.51 0.46 0.45
Syringol 0.47 0.20 0.73 0.38 0.38 0.37 0.43 0.41
Phenol 0.12 0.44 0.65 0.30 0.30 1.14 0.95 0.16
O
O
H
HO
O
OH
OCH3
OH
OCH3
OCH3
Bio‐oil Stability
• Aging accelerated by storing bio‐oils at 90 °C for 8h and 24h
Bio‐oil Stability: Mw
Mw
300
350
400
450
500
550
600
650
0 4 8 12 16 20 24
Time at 90 C (h)
MW
Oak Barley Straw Corn Stover Ryegrass Switchgrass Soy Straw
Economic Analysis: 200 TPD plant
Feedstock43%
Utilities including Make Up
water9%
Labor,Supplies
and Overhead
22%
Depreciation26%
Bio-oil Production Costs
Operating Costs ($/ Barrel Bio‐oil)
Feedstock $13.686Utilities including Make Up water $2.941
Labor, Supplies and Overheads $7.172
Depreciation $8.384
CoProduct Credits ‐$0.832
Cost per 42 Gallon Barrel $31.351
Cost per Equivalent Barrel of Oil $52.25
( Energy Basis)
Bio‐oil Upgrading
• Ex‐Situ upgrading is required to remove oxygen from bio‐oil to produce hydrocarbons– Hydroprocessing
– Catalytic Cracking
– Steam Reforming
• In‐Situ Upgrading (Catalytic Pyrolysis) can be used to produce stable partially deoxygenated bio‐oils and make further upgrading more facile
Catalytic Pyrolysis of Lignin(py‐GC/MS)
No Catalyst
with HZSM-5
AromaticHydrocarbon
Mechanisms of In Situ Catalytic Cracking
HO
R'
RO
R'
O
L
L
OH
R, R' = H: H/G LigninR = H, R' = OMe: G/S LigninR, R' = OMe: S LigninL = Additional Lignin Units
HO
R
R'Guaiacols
andSyringols
Depolymerization
Depolyermization+ Demethoxylation
HO
SimplePhenols
+ MeOH
+ O
R'
O
L
L
Lignin Oligomers
HZSM-5
Catalyst Deactivation
HZSM-5
Olefins
Aromatics
HZSM-5FurtherDepolyermization
HO
R
R'Guaiacols
andSyringols
Aromatics
OlefinsHO
SimplePhenols
DemethoxylationMeOH +
HZSM-5
Catalyst Deactivation
1° PyrolysisReactions
1° PyrolysisReactions
+ CO
HZSM-5
HZSM-5
HZSM-5
Carbohydrates
Lignin
Execution Plan
ElectricityProduction
Fuel OilSubstitution
Transport Fuels(Gasoline, Jet
Diesel)
Chemicals
Process
Feedstock
Ex-Situ(HYDROTREATING)
Ex-Situ(HYDROTREATING)
In-Situ Catalysis(VAPOR)
In-Situ Catalysis(VAPOR)
In-Situ Catalysis(BED)
In-Situ Catalysis(BED)
BIOMASSBIOMASS
CatalyticPyrolysis
Partial Stabilization/
DeoxygenationNon-
CatalyticPyrolysis
Full Stabilization/
Deoxygenation
Bio‐oilStabilization
DROP-IN3 Years to complete
R&D
ContingencyAvailable
Today
Green Jet-range Paraffins(Bio-SPK)
Selective Cracking/
Isomerization
Natural Oils and
FatsDeoxygenation
Renewable Jet Fuel
Solid Biomass
Catalytic Stabilization/
DeoxygenationPyrolysis
Jet Range Cyclic
Hydrocarbons
2nd Generation Renewable Jet Fuel from Oils and Biomass
The Future: 100% Renewable Jet
The hydroplane ran on 98% Bio-SPK and 2% renewable aromatics
Jet A1Spec
Starting SPK
Woody Pyrolysis Oil Aromatics
Freeze Point (oC) -47 -63 -53Flash Point (oC) 39 42 52Density (g/mL) 0.775 0.753 0.863
Bio‐char Co‐product
• Energy Value: only $25/ton based on coal selling price of $1.10/Gj
• In light that world’s soils hold more organic C than that held by the atmosphere as CO2& vegetation; the land is a major factor in C‐sequestration
• As the earth is stressed to produce more food, fiber & energy more C is removed from ground & emitted to atmosphere
• Impacts soil’s fertility and threatens its long‐term effectiveness.
• Biochar is one solution to slow down and even reverse the process ‐ UNCCD, Poznan, 2008
Terra Preta/Chernozems Oxisol
Glaser et al. (2001) Naturwissenschaften, 88:37–41
Fast Pyrolysis bio‐chars and Steam Activation
Corn Stover Biochar Carbon
Bio‐char Advantages
• Bulk Density
• Enhances plant available water in sandy soils and aeration in clay soils
• Enhances soil fertility
• Absorbs organic & inorganic pollutants (cationexchange)
• Increases crop yield
• Sequesters carbon (half life ~ 1000 yr)
Bio‐carbon Metal Adsorption1 mM aqueous solutions
Cu2+
Broiler LitterSwitchgrassAlfalfa
Corn cob carbonCorn stover carbon
Corn Stover Bio-charCorn Cob Bio-char
Soybean straw
Cd2+ Ni2+ Zn2+% Adsorption
79.746.882.978.298.154.580.395.7
84.816.521.16.8
90.522.6
31.121.0
96.4-
19.7
95.812.3
29.230.0
13.4
39.521.036.112.595.321.337.227.8
PUR RF 51.0 15.229.217.1
Thank You
CRIS-082 CRADA Partners