Bioenergy Program
Department of Forest Biomaterials
Faculty in Bioenergy Science and Technology
Dimitris Argyropoulos
Professor
Wood Chemistry
Hasan Jameel
Professor
Process Engineering
Orlando Rojas
Associate Professor
Surface Chemistry
Med Byrd
Associate Professor
Process Development
Stephen Kelley
Dept Head & Professor
Polymer Chemistry
Daniel Saloni
Assistant Professor
Process Development
Hou-min Chang
Professor Emeritus
Wood Chemistry
Vincent Chiang
John Heitmann
Martin Hubbe
Professor
Professor
Professor
Forestry Biotechnology Enzyme Biotechnology Surface Chemistry
Adrianna Kirkman
Professor
Process Simulation
David Tilotta
Associate Professor
Wood Chemistry
Lucian Lucia
Associate Professor
Wood Chemistry
Richard Venditti
Associate Professor
Life Cycle Analysis
Sunkyu Park
Richard Phillips
Assistant Professor Executive in Residence
Bioenergy Process Bioenergy Economics
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
5
Background
• Concept inception October 2006
• Ponderosa Consortium
–
–
–
–
–
–
–
–
–
2007
Arborgen
BE&K Engineering
International Paper
Genencor
Metso Paper
Stone Smurfit
Syngenta
Weyerhaeuser
Xethanol
6
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
7
Pulp and Paper - Base Case Mill
8
Ponderosa Asset Reuse
Lignin To
Power Boiler
9
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
10
Capital Costs1
in $2009
Ethanol, Liters
Repurpose B1
241,015,752
Repurpose B2
240,225,758
Repurpose B4
274,062,729
Repurpose B6
380,216,046
Repurpose B7
169,866,977
Repurpose B8
249,278,852
63,669,622
63,461,129
72,399,939
100,442,766
44,874,248
65,852,711
Ethanol, Gallons
$
1,191,000
5,475,960
$
3,132,000
$
1,611,522
$
5,817,000
$
3,290,436
$
5,350,000
$
172,721,000
$
109,847,934
$
155,340,324
17,212,000
$
30,341,000
$
12,857,326
$
17,212,000
$
3,480,000
$
3,480,000
$
3,480,000
$
3,480,000
220,528,000
$
225,944,000
$
246,792,000
$
136,563,000
$
185,705,000
3.48
$
3.12
$
2.46
$
3.04
$
2.82
-
$
-
$
-
12,478,000
$
Continous Digester Modifications $
12,296,000
$
32,564,000
$
32,564,000
$
32,564,000
$
Hydrolysate Cleanup $
1,762,000
$
1,892,000
$
1,879,000
$
1,869,000
Additional Hydrolysis Retention $
4,769,000
$
5,178,000
$
5,350,000
$
Alcohol Plant $
150,127,000
$
160,423,000
$
165,459,000
Lignin Separation and Burning $
16,100,000
$
16,991,000
$
Bleach Plant Modifications $
3,480,000
$
3,480,000
Total $
201,012,000
$
Capital Cost per Gallon Ethanol $
3.16
$
1 BE&K
-
$
Batch Digester Modifications $
Estimates based on file histories
11
-
Manufacturing Cost
Enzyme at $0.30 per Gallon
Constant
Wood
+10%
Wood
100%
Pine +
Residuals
100%
HWD +
Residuals
• Hardwood cost per ton higher than
softwood but ethanol yield is greater
• Higher ethanol yield leads to lower
Indirect costs
Constant
Wood
• 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
+10%
Wood
12
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
13
WERC Consortium
• Used Ponderosa as guidance for second consortium aimed at
simplification (currently in progress)
– WERC – “Wood Ethanol Research Consortium”
2008 – 2009
•American Process
•Arborgen
•Andritz
•BE&K Engineering
•Catchlight Energy/Weyerhaeuser
•Evolution Resources
•Nippon Paper/JPPRI
•NC State Natural Resources Foundation
14
Simplification of Pretreatment
• 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
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%
Sugars as monomer
Sugar Re cov ery 
Total carbohydra tes in wood
Green Liquor Repurpose Case B10
Wood
+ Forest Residues
Woodyard
Prehydrolysis
Cook
Ethanol
Product
Waste
Treatment
Beer
Column
Distillation
Dehydration
Hydrolysate
Cleanup
Fermentation
Fiber
Hydrolysis
Lignin
Recovery
Brownstock
Washers
Screens
PM1
Brownstock
Washers
Screens
PM2
Continuous
Digester
Lime
Kiln
Power
Sales
Sawdust
ClO2
Generation
Evaporators
Causticizing
Recovery
Boiler
Power
Generation
Power
Boiler
17
Natural
Gas
18
19
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
Process
Softwood
Tot. sugar in pulp
(% on wood)
62.8
Sugar recovery (%)
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 success
Maintenance and Energy Cost next most critical
$1.79 per Gallon
22
Softwood Cash Costs better than Hardwood
$1.70 per Gallon
23
Commercialization Status
• One consortium member negotiating to acquire 1-3 assets that
have been shut down or in the process of being closed
– Bastrop, Louisiana: Uncoated free sheet, high HW
– Franklin, Virginia: Uncoated free sheet, high HW
– Pineville, Louisiana: Linerboard, SW
• Engineering studies are being conducted at one location with
estimates of capital cost
• Propose to start up in 1.5 years
24
Ethanol from Transgenic Hardwoods
• Sungrant (DOT)
• Evaluate potential for simplifying pretreatments for
low/modified lignin hardwoods
Samples Lignin S/G
– Autohydrolysis
– Ozone
– Mild alkaline
Wildtype
TG96
TG141
23
24
11
Figure 1. Effect of lignin content on glucose
yield from wildtype and transgenic woods
Glucan
2.2
44
6.4
45
2.6
54
Advanced Technology for Low Cost Ethanol
from Engineered Cellulosic Biomass
•
•
•
•
USDA - DOE
Demonstrate transgenic tree plantations with fast growing low lignin/high
cellulose transgenic trees
Demonstrate on a pilot scale the improved processability and economics,
including simplified pretreatment strategies
Economic evaluation of the different biomass and process options, using
standard investment analysis techniques, including all applicable
subsidies
Economics and Feasibility of North Carolina
Biomass Conversion
•
Indentify the most suitable and profitable
scheme to produce ethanol in North Carolina
with a complete analysis of the Supply Chain
70,000
Total acres
Land investment ($)
70
66,999
60,000
60
50,249
50,000
50
Acres
Agriculture biomass
1. Switch grass
2. Myscanthus
3. Coastal bermuda grass
4. Corn stover
5. Sugar beet
6. Arundo donax
7. Sweet sorghum
80
Acres to harvest
40,200
40,000
40
30,000
30
20,000
20
13,400
10,050
10,000
8,040
0
10
0
7.5 BDT/acre/year
10 BDT/acre/year
12.5 BDT/acre/year
Land investment (Millions $)
Forest biomass
1. Hardwoods: Eucalyptus, poplar, mixed hardwood
2. Pine
80,000
3. Forest residues
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
Pretreatment
Bio-ethanol
Coastal Bermuda
Grass Bales
Untreated
AFEX treated
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
Negative feedstock
cost
Contains CaCO3 and
inorganics
Papermaking Sludges
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
PULP & PAPER
WOOD CHIPS
DIGESTER
CHEMICALS
FERMENTATION
ETHANOL
31
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
Woody Biomass
Hot Water
Extraction
Combustion
Ethanol – Acetic Acid
Opportunities with Dissolved Wood
for the Forest Biorefinery
Certain Ionic Liquids Can
Completely Dissolve Wood
Time
recycling of IL’s
Lignin Based
Comodity
Chemicals / Phenolics
New Value –Added
Materials
Kraft Lignin
Oxidative Dealkylation
Wood
Modification
Fully
Dissolved
Wood & Components
Wood Based
Comodity &
Speciality
Chemicals/
Furanoids
Component Fractionation
Biofuels
Liquid Wood
Novel Exruded
Wood Products
Hemicellulose
Cellulose
Dimitris S. Argyropoulos
Cellulose Fibers
Enhancing Wood Penetration for More Efficient
Hydrolysis and Optimized Saccharification
2+
H2O
Ir
OH2
Ir
NO3
NO3
H2O
Morphology of a microemulsion
represented by a random bicontinuous
structure or a Schwartz surface.
= surfactant
The metal (IrCp*)-cellulase complex is later recovered
and the SOW (Surfactant Oil-Water) micro-emulsion may
also be recycled
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
Raw Materials
Energy
Production
Waste
Energy
Transportation
Waste
Emissions to air
and water
Energy
Use
Waste
Emissions to air
and water
Emissions to air
and water
CORRIM Consortium for Research on
Renewable Industrial Material
Energy
Disposal
Waste
Emissions to air
and water
Validation of Therminator Syngas Cleanup
•
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
36
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