Bioenergy ProgramBioenergy ProgramDepartment of Forest Department of Forest BiomaterialsBiomaterials
Faculty in Bioenergy Science and Technology
Dimitris ArgyropoulosProfessor
Wood Chemistry
Med ByrdAssociate Professor
Process Development
Hou-min ChangProfessor Emeritus
Wood Chemistry
Vincent ChiangProfessor
Forestry Biotechnology
Martin HubbeProfessor
Surface Chemistry
Stephen KelleyDept Head & Professor
Polymer Chemistry
Adrianna KirkmanProfessor
Process Simulation
Lucian LuciaAssociate Professor
Wood Chemistry
Sunkyu ParkAssistant ProfessorBioenergy Process
Richard PhillipsExecutive in ResidenceBioenergy Economics
Orlando RojasAssociate ProfessorSurface Chemistry
Daniel SaloniAssistant Professor
Process Development
David TilottaAssociate Professor
Wood Chemistry
Richard VendittiAssociate ProfessorLife Cycle Analysis
Hasan JameelProfessor
Process Engineering
John HeitmannProfessor
Enzyme Biotechnology
Bioenergy Projects
• Wood-to-Ethanol Research Consortium
• Value Prior to Pulping (VPP)
• Ethanol from Transgenic Hardwoods
• Ethanol from Coastal Bermuda Grass
• Enhancing Wood Penetration for More Efficient Hydrolysis and Optimized Saccharification
• Opportunities with Dissolved Wood for the Forest Biorefinery
• Validation of Therminator Syngas Cleanup
• Advanced Technology for Low Cost Ethanol from Engineered Cellulosic Biomass
• Economics and Feasibility of North Carolina Biomass Conversion
• Producing Ethanol from Biomass by Extracting Value Prior to Extraction
• Low Cost Conversion of Industrial Sludges to Ethanol
• Integrated Torrefaction-Gasification for the Production of Biofuels
• Economic Analysis of Pine Biomass Varieties for Ethanol Production
• Life Cycle Analysis for the Production of Transportation Fuels
• Fast Pyrolysis of Forestry Biomass
Wood to Ethanol Research Consortium (1)
• Industry consortium of six companies
• Repurposing a kraft pulp mill into a ethanol mill
• Develop cost effective process by reusing existing assets
Background
• Majority of bioethanol in United States is produced from corn, none from wood– Wood is competitive with corn in carbohydrate content with corn– Cheaper raw material– Capital cost to build large scale plant 2-3 X Corn Plant– Increasing controversy over use of corn for fuel vs food
• Demand for paper and board declining in United States– > 9 Million tons of capacity have permanently closed in United
States since 2000– Kraft pulp mills can potentially be repurposed to ethanol production
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Background
• Concept inception October 2006
• Ponderosa Consortium 2007– Arborgen– BE&K Engineering– International Paper– Genencor– Metso Paper– Stone Smurfit– Syngenta– Weyerhaeuser– Xethanol
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Advantages of Repurposing a Kraft Mill to Ethanol
1. Assets can largely be reused without serious compromise
2. Biomass supply chain in place to grow – harvest – deliver large amounts of wood
3. Low cost harvesting residuals frequently left behind in a kraft mill can be effectively used in ethanol production
4. Equipment in place is commercially proven and needs no additional development
5. Workforce in place, trained, likely motivated to succeed
6. Environmental permitting likely to straightforward
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Pulp and Paper - Base Case Mill
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Ponderosa Asset Reuse
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Lignin To Power Boiler
Repurpose Cases Considered
• Repurpose A– Same wood volume by species and form as Base Case
• Repurpose B1– Same as Repurpose A + 10%
• Repurpose B2– Same as B1 except 100% Pine – no debarking + 15% Harvesting
Residuals
• Repurpose B4– Same as B1 except 100% Hardwood – no debarking + 40%
Harvesting Residuals
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Capital Costs1
in $2009
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Repurpose B1 Repurpose B2 Repurpose B4 Repurpose B6 Repurpose B7 Repurpose B8Ethanol, Liters 241,015,752 240,225,758 274,062,729 380,216,046 169,866,977 249,278,852
Ethanol, Gallons 63,669,622 63,461,129 72,399,939 100,442,766 44,874,248 65,852,711
Batch Digester Modifications 12,478,000$ -$ -$ -$ -$ 1,191,000$
Continous Digester Modifications 12,296,000$ 32,564,000$ 32,564,000$ 32,564,000$ 5,475,960$ 3,132,000$
Hydrolysate Cleanup 1,762,000$ 1,892,000$ 1,879,000$ 1,869,000$ 1,611,522$ -$
Additional Hydrolysis Retention 4,769,000$ 5,178,000$ 5,350,000$ 5,817,000$ 3,290,436$ 5,350,000$
Alcohol Plant 150,127,000$ 160,423,000$ 165,459,000$ 172,721,000$ 109,847,934$ 155,340,324$
Lignin Separation and Burning 16,100,000$ 16,991,000$ 17,212,000$ 30,341,000$ 12,857,326$ 17,212,000$
Bleach Plant Modifications 3,480,000$ 3,480,000$ 3,480,000$ 3,480,000$ 3,480,000$ 3,480,000$
Total 201,012,000$ 220,528,000$ 225,944,000$ 246,792,000$ 136,563,000$ 185,705,000$
Capital Cost per Gallon Ethanol 3.16$ 3.48$ 3.12$ 2.46$ 3.04$ 2.82$
1 BE&K Estimates based on file histories
Manufacturing CostEnzyme at $0.30 per Gallon
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ConstantWood
+10% Wood
100%Pine +
Residuals
100%HWD +
Residuals
• Hardwood cost per ton higher thansoftwood but ethanol yield is greater
• Higher ethanol yield leads to lowerIndirect costs
• Cash Cost of Repurpose B4 –100% Hardwood
• $1.90 per Gallon Total Cash Cost• $0.25 per Gallon Energy Cost• $0.30 per Gallon Enzyme Cost• $0.61 per Gallon Biomass Cost
ConstantWood
+10% Wood
100%Pine +
Residuals
100%HWD +
Residuals
Summary
• Repurposing existing Kraft Pulp Mill Promising:
– Many practical advantages
– Wood – to – Ethanol process with a potential Internal Rate of Return > 20%
– Ethanol cash manufacturing cost ~ $1.60 per Gallon ($0.42 per liter) with enzymes at $0.30 per Gallon
• Requires simplification
– Too many people on payroll due to complex process
– Higher maintenance cost compared to corn
– Distillation and fermentation costs high due to low sugar concentrations
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WERC Consortium
• Used Ponderosa as guidance for second consortium aimed at simplification (currently in progress)– WERC – “Wood Ethanol Research Consortium”
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2008 – 2009
•American Process
•Arborgen
•Andritz
•BE&K Engineering
•Catchlight Energy/Weyerhaeuser
•Evolution Resources
•Nippon Paper/JPPRI
•NC State Natural Resources Foundation
• Pretreatment methods in a Repurposed Mill– Autohydrolysis (AH)
• Acetic acid prehydrolysis (Hac)
– Sodium Carbonate (SC)– Green liquor (GL)
• Autohydrolysis/green liquor (AH-GL & HAc-GL)– Sodium Carbonate/Sodium Hydroxide
Yongcan Jin
Simplification of Pretreatment
Summary
Pretreatment Sugar Recovery
Autohydrolysis 45%
Acetic Acid Autohydrolysis 73%
Sodium Carbonate 50%
Green Liquor 80%
Autohydrolysis Green Liquor 74%
Acetic Acid Autohydrolysis- Green Liquor
79%
Sodium Carbonate-Sodium Hydroxide 68%
woodintescarbohydraTotal
monomerasSugarserySugar covRe
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Green Liquor Repurpose Case B10
RecoveryBoiler
WasteTreatment
PM2
Sawdust
Woodyard
BrownstockWashers
Screens
PM1Brownstock
WashersScreens
Evaporators
PowerBoiler
NaturalGas
DistillationBeer
Column
FermentationFiber
HydrolysisPrehydrolysis
Cook
Dehydration
EthanolProduct
HydrolysateCleanup
ClO2Generation
Wood+ Forest Residues
PowerSales
LigninRecovery
LimeKiln
PowerGeneration
Causticizing
ContinuousDigester
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Use of Oxygen and Refining for Softwood
• Oxygen delignification and refining can improve enzymatic hydrolysis– Both these unit operations may be available in a repurposed mill
Softwood Options in a Repurposed Mill
ProcessTot. sugar in pulp
(% on wood)Sugar recovery (%)
Softwood 62.8 Basis on Tot. sugar in wood
GL16-25S-170 42.4
GL16-40S-170 45.9
GL16-25S-170-R 58.8
GL16-40S-170-R 64.0
GL16-25S-170-O 62.6
GL16-40S-170-O 68.0
GL16-25S-170-O-R 69.8
GL16-40S-170-O-R 74.4
Hardwood Fiber, Enzyme Costs Critical to successMaintenance and Energy Cost next most critical
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$1.79 per Gallon
Softwood Cash Costs better than Hardwood
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$1.70 per Gallon
Commercialization Status
• One consortium member negotiating to acquire 1-3 assets that have been shut down or in the process of being closed– Bastrop, Louisiana: Uncoated free sheet, high HW– Franklin, Virginia: Uncoated free sheet, high HW– Pineville, Louisiana: Linerboard, SW
• Engineering studies are being conducted at one location with estimates of capital cost
• Propose to start up in 1.5 years
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Ethanol from Transgenic Hardwoods
• Sungrant (DOT)
• Evaluate potential for simplifying pretreatments for low/modified lignin hardwoods
– Autohydrolysis
– Ozone
– Mild alkaline
Samples Lignin S/G GlucanWildtype 23 2.2 44TG96 24 6.4 45TG141 11 2.6 54
Figure 1. Effect of lignin content on glucose yield from wildtype and transgenic woods
Advanced Technology for Low Cost Ethanol from Engineered Cellulosic Biomass
• USDA - DOE
• Demonstrate transgenic tree plantations with fast growing low lignin/high cellulose transgenic trees
• Demonstrate on a pilot scale the improved processability and economics, including simplified pretreatment strategies
• Economic evaluation of the different biomass and process options, using standard investment analysis techniques, including all applicable subsidies
Economics and Feasibility of North Carolina Biomass Conversion
• Indentify the most suitable and profitable scheme
to produce ethanol in North Carolina with a
complete analysis of the Supply Chain
Forest biomass1. Hardwoods: Eucalyptus, poplar, mixed hardwood 2. Pine3. Forest residues
Agriculture biomass1. Switch grass2. Myscanthus3. Coastal bermuda grass4. Corn stover5. Sugar beet6. Arundo donax7. Sweet sorghum
13,400 10,050 8,040
66,999
50,249
40,200
0
10
20
30
40
50
60
70
80
0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
80,000
7.5 BDT/acre/year 10 BDT/acre/year 12.5 BDT/acre/year
Lan
d in
vest
men
t (M
illio
ns $
)
Acres to harvest Total acres Land investment ($)
Acr
es
Ethanol from Coastal Bermuda Grass
• Develop simplified pretreatments for the conversion of coastal Bermuda grass to ethanol– Autohydrolysis– Sodium Carbonate– Ozone– Ammonia Explosion– Microwave/NaOH– Lime
Untreated AFEX treated
Coastal Bermuda Grass Bales
Bio-ethanol
PretreatmentPretreatment
Economic Analysis of Pine Biomass Varieties as Feedstock for the Production of Ethanol
• Characterize 178 pine varieties to identify those with varying lignin and cellulose content
• Select 20 varieties with different wood properties, and perform chemical and physical characterization of the wood properties
• Measure fermentable sugar yield using three pretreatments (dilute-acid, weak alkaline, organosolv)
• Compare feedstock value of different pine and poplar and recommend ideal loblolly pine feedstock
Low Cost Conversion of Industrial Sludges to Ethanol
• Biofuels Center of North Carolina
• Demonstrate an effective technology to convert industrial papermaking sludge as a cost effective feedstock for the efficient biochemical biomass conversion to ethanol
Papermaking Sludges
Negative feedstock costContains CaCO3 and inorganics
Value Prior to Pulping
• DOE and Consortium of Companies and various research organizations
and universities
• Extract hemicelluloses prior to pulping and convert to ethanol and
chemicals
31ETHANOLFERMENTATION
WOOD CHIPS PULP & PAPER
DIGESTER
CHEMICALS
Producing Ethanol from Biomass by Extracting Value Prior to Combustion
• Develop a process for hot water treatment of wood to extract the hemicelluloses.
• Following extraction, the wood residue is sent to a boiler and burned as conventionally
practiced
CombustionWoody BiomassHot WaterExtraction
Ethanol – Acetic Acid
Certain Ionic Liquids Can Completely Dissolve Wood
Time
Opportunities with Dissolved Wood for the Forest Biorefinery
Cellulose Fibers
Lignin BasedComodity
Chemicals / PhenolicsNew Value –Added Materials
Component Fractionation
FullyDissolved
Wood & Components
Kraft LigninOxidative DealkylationWood
Modification
Cellulose
Novel Exruded Wood Products
Liquid Wood
recycling of IL’s
Wood BasedComodity &Speciality
Chemicals/Furanoids
Hemicellulose
Biofuels
Dimitris S. Argyropoulos
Enhancing Wood Penetration for More Efficient Hydrolysis and Optimized Saccharification
The metal (IrCp*)-cellulase complex is later recovered and the SOW (Surfactant Oil-Water) micro-emulsion may also be recycled
Morphology of a microemulsion represented by a random bicontinuous
structure or a Schwartz surface.
IrH2O OH2
H2O
IrNO3 NO3
2+
= surfactant
Life Cycle Analysis for the Production of Transportation Fuels
• Perform detailed material and energy balances on a set of biofuel manufacturing processes and feedstocks
• Develop equipment and facility engineering plans for the processes/feedstocks
• Perform a life cycle analysis on the processes/feedstocks and report the relative impacts of the different processes/feedstocks
Production Transportation Use Disposal
Raw Materials
Energy EnergyEnergy Energy
Waste WasteWasteWaste
Emissions to air and water
Emissions to air and water
Emissions to air and water
Emissions to air and water
CORRIM Consortium for Research on Renewable Industrial Material
Validation of Therminator Syngas Cleanup
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• US Department of Energy
• Validate syngas cleanup technology (“Therminator”, RTI International) and syngas conversion unit operation
• Integrate into the gasification process at the University of Utah
• A fixed bed or slurry bubble column reactor will be integrated downstream of the “Therminator” to produce FT waxes from RTI’s proprietary iron-based catalyst
Integrated Torrefaction-Gasification for the Production of Biofuels
• Turn woodchips into a substitute for coal by using a process called torrefaction that is greener, cleaner and more efficient than traditional coal burning.
• Quantify relationship between time and temperature to produce torrefied wood
• Use of torrefied wood for gasification
• Scale up process to pilot plant evaluation
• Economic and life cycle analysis of combine process
Fast Pyrolysis Bio-oil from Forest Resources
• NSF I/UCRC (Industry/University Cooperative Research)
• 43mm fluidized bed reactor for fast pyrolysis
• Assess the quality of bio-oils produced from forest resources including forest residue, small diameter wood, and deconstruction materials
• Investigate statistical relationships between feedstock lignin content and specific bio-oil properties