Transcript 2005 OBP Bi-Annual Peer Review Project Presentation Template

2005 OBP Biennial Peer Review
Pretreatment & Enzymatic Hydrolysis
Rick Elander (NREL)
Biochemical Conversion Platform
November 15, 2005
Work Breakdown Structure
2.0
Biochemical Platform
2.3
2.2
2.1
Feedstock-Biochemical Process Integration
Pretreatment and
Enzymatic Hydrolysis
Interface
2.1.1
Pretreatment and
Enzymatic Hydrolysis
2.1.1.1
CAFI 2 Support
2.1.1.2
Feedstock Qualification
2.1.1.2.1
Extended Fiber
Pretreatment
2.1.1.3
Forest Biorefinery
2.1.1.4
Enzymatic Hydrolysis
2.1.1.5
Exploratory Pretreatment
2.1.3
Integration of Leading
Biomass Pretreatment
Technologies (CAFI 2)
7.04.2.GO41221
Rheology and
CFD Modeling
2.2.4
Preprocessing and
Storage Systems
Development/Qualification
2.2.5
Preprocessing Feedstock
Supply
2.4
2.5
Targeted Conversion Biochemical Platform
Analysis
2.3.1
Processing Integration
2.4.1
Targeted Conversion
Research
2.3.1
Feedstock Variability
2.4.1.1
Chemical Conversion
Fundamentals
2.3.2
Integrated Processing
2.4.2
Biological Processing
Fundamentals
2.3.3
Analytical Methods
2.4.3
Plant Cell Wall
Deconstruction
2.4.4
BSCL and Genomics
2.4.4
Industrial Membrane
Filtration & Short Bed
Fractal Separation
NREL
Academia
Industry
Earmark
Platform Fit with Pathways
Feedstock
R&D
Sugars
R&D
Thermochemical
R&D
Products
R&D (from)
Integrated
Biorefineries
Program Outputs
Corn Wet Mill
Improvements
(Corn)
•Residual Starch Conversion
•Fiber Conversion
Corn Dry Mill
Improvements
(Corn, Grain)
•Residual Starch Conversion
•Fiber Conversion
•Milled Grain Fractionation
Agricultural
Residue Processing
(Corn Stover, Wheat
Straw, Rice Straw)
•Biomass Fractionation
•Sugars Production
Energy Crops
(Perennial Grasses,
Woody Crops)
•Biomass Fractionation
•Sugars Production
Pulp and Paper Mill
Improvements
(Mill Wastes, Wood)
Element
Strategic
Goals
•New Fractionation Process
for hemiicellulose removal
Sustainably supply
biomass to
biorefineries
Low-cost sugars from
lignocellulosic
biomass
• Aventine/Purdue
Systems-level
demonstration and
validation by 2009
Systems-level
demonstration and
validation by 2012
•
•
•
•
•
CAFI 2
Feedstock Qualification
Enzymatic Hydrolysis
Exploratory (Prt.) Sacch.
Rheology/CFD Modeling
• CAFI 2
• Feedstock Qualification
• Exploratory (Prt.) Sacch.
• Forest Biorefinery
(Hemicellulose Ext.)
Chemical building
blocks from
lignocellulosic
biomass
Fuels, chemicals and
power from bio-based
sugars and chemical
building blocks
Systems-level
demonstration and
validation by TBD
Systems-level
demonstration and
validation by TBD
Systems-level
demonstration and
validation by 2010
Biomass Program
Strategic Goal
Cost-competitive
biorefinery technologies
for the nation’s
transportation, chemical
and power industries
Barriers
Commercial Success Barriers
Price of Sugars from “Cellulosic” Biomass
Major General Barriers
Feedstock Cost
Sugars Composition
Sugars Yield
Conversion Rate
Sugars Quality
Capital Investment
R&D Technical Barriers
Feedstock-Sugars Interface
Biomass Pretreatment
Enzymatic Hydrolysis
Sugars Processing
Process Integration
• Biomass Recalcitrance
• New Pathways
• Enabling Tools
Overview
Budget (FY05)
Partners
University of
Louisville
$295K
CAFI 2
$628K
Sugar Platform
Analysis
$205K
•
Pretreatment &
Enzymatic Hydrolysis
Targeted Conversion
Research
•
•
$3,127K
Sugar Process
Integration
$2,025K
$3,014K
$1,000
FY04
FY05
FY06
$900
$800
$K per year
$700
FY00
$600
$500
$400
$300
$200
$100
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NREL (Pretreatment and
Enzymatic Hydrolysis Task)
Aventine/Purdue University
CAFI Universities
–
–
–
–
–
Auburn University
Dartmouth College
Michigan State University
Purdue University
Texas A&M University
–
University of British Columbia
Neoterics Int’l.
Harris Group Inc.
Novozymes
Genencor Int’l.
Merrick & Co.
University of Louisville
Approach
• Overall Goal: Enable less severe (less costly) pretreatment
and more economical enzymatic hydrolysis/sugar production
• Understand how pretreatment alters biomass structure and composition
• Assess required enzyme loadings and types
• Understand response of feedstock types representing several pathways
• Across different pretreatment processes and ranges of severities
• Role of non-cellulase enzymes
• High solids pretreatment and saccharification
2.4.
Targeted
Conversion
Research
2.1.
Pretreatment and
Enzymatic
Hydrolysis
2.3.
Processing
Integration
Pretreatment and Enzymatic
Hydrolysis Projects
• Projects Supporting Near Term Biorefinery
Opportunities
• Bridge to Corn Ethanol Project (Aventine/Purdue)
• Hemicellulose Extraction Subtask (NREL)
• Pretreatment Effects on Feedstock Structure and Types
• Exploratory Saccharification Subtask (NREL)
• Feedstock Qualification Subtask (NREL)
• Integration of Leading Biomass Pretreatments Project (CAFI 2)
• Enzymatic Hydrolysis and High Solids Processing
• Enzyme Subcontract Liaison Subtask (NREL)
• Enzymatic Hydrolysis Subtask (NREL)
• Rheology and CFD Modeling Project (Univ. Louisville)
Bridge to Corn Ethanol–
Aventine/Purdue
• Objective: Demonstrate conversion of residual starch and
lignocellulosic carbohydrates in wet mill corn fiber
• Work has progressed from bench scale to in-plant pilot-scale testing over
5 years (with technoeconomic analysis guidance)
• Simple, low cost approach that readily integrates into
existing wet mill
• Economic risks mitigated by integrating into existing commercial facility
• Bench scale results and economic analysis decision
points indicated sufficient potential to proceed to in-plant
pilot testing at Aventine
• Broad multidisciplinary collaboration involving Aventine,
Purdue, NREL, USDA, Illinois Corn Marketing Board
Bridge to Corn Ethanol–
Aventine/Purdue
• Technical challenges focused on process validation at scale and
equipment performance
• Material handling and heat transfer have proven challenging
• Slurry viscosity spikes during initial heat-up, then falls during pretreatment
• Process robustness not yet validated for extended continuous operation
• Modifications to heat exchanger, pump, and centrifuge underway to
enable more reliable operation
Forest Biorefinery-Hemicellulose Extraction
• Objective: Partially extract hemicellulose prior to chemical or
thermomechanical pulping while retaining pulp quality
• Solubilize enough sugars to permit economically viable ethanol production
• Limit risks by focusing on key issues of hemicellulosic sugar
recovery yields and pulp properties
• Address other R&D issues later (e.g., oligomer conversion, acetic acid
recovery, fermentation)
• Initial milestones on sugar yields and potential ethanol
economics look attractive under certain scenarios (strongly
influenced by assumptions about utility and enzyme costs)
• Some issues concerning pulp quality identified (that are being addressed by
USDA FPL and academic participants in Agenda 2020 consortium)
• Results to inform a go-no go decision for a “Stage 3” cost-shared industryled consortium project
Forest Biorefinery-Hemicellulose Extraction
PreDigester
Chip Pile
Ferment
Hemicellulose
Sugars
Ethanol
or
Chemicals
● Completed a series of hemicellulose
extractions at various conditions for maple
and spruce chips
● Preliminary economic analysis for ethanol
production conducted
Digester
● Extracted chips supplied to the USDA’s Forest
Product Lab to evaluate pulp quality
Paper Products
Recirculating Chip Extractor
100%
90%
80%
70%
Conversion of Polymer
Steam
60%
Total Xylan Conversion
Xylan to Total Xylose
Xylan to Oligomer
50%
Xylan to Monomer
Xylan to Furfural
40%
Acetate to Acetic Acid
30%
20%
10%
Extract Liquor
0%
Run 4
145 C-2 hr Avg
Run 2
160 C-1 hr Avg
Run 1
160 C-2 hr Avg
Run 3
160 C-4 hr Avg
Exploratory (Pretreatment)
Saccharification
• Objective: Understand biomass ultrastructure effects
• Pretreatment catalyst transport (corn stem as a model)
• Identify required enzyme activities as a function of pretreatment approach
• Enable a less severe pretreatment that achieves high sugar yields
• Highly integrated with other subtasks in Pretreatment &
Enzymatic Hydrolysis and Targeted Conversion tasks
• Feedstock Qualification subtask generates pretreated samples from
different feedstock types across a range of pretreatment pHs/severities
• “Joint” milestone with Plant Cell Wall Deconstruction subtask (9/05)
• Leveraging “CAFI 2” comparative pretreatment project
• Accessing “progressively” pretreated samples to understand how
composition and structure change as pretreatment proceeds (effect on
enzyme loading and required enzyme activities)
Exploratory (Pretreatment)
Saccharification
Corn stem xylem
No pretreatment
Enzyme Augmentation Studies on
ARP (CAFI) Pretreated Corn Stover
% Glucan Conversion
Surface Ultrastructure Changes
Upon Dilute Acid Pretreatment
100
80
60
40
20
0
AARP#1
AARP#2
AARP#3
AARP#4
Spez(15)
Spez(25)
Spez(125)
Spez(15) GCI MF Xylanse (10)
Spez(15) Sigma XynA (3)
Spez(15) BG 1000 (10)
Corn stem xylem
1.5% H2SO4,150oC, 20 min
% Xylan Conversion
Spez(15) Optimash BG(10)
100
80
60
40
20
0
AARP#1
AARP#2
AARP#3
AARP#4
Spez(15)
Spez(25)
Spez(125)
Spez(15) GCI MF Xylanse (10)
Spez(15) Sigma XynA (3)
Spez(15) BG 1000 (10)
Spez(15) Optimash BG(10)
Feedstock Qualification
• Objective: Develop and apply a method for screening
pretreatment pH and severity effects across feedstock types
• Generate comparative pretreatment reactivity data for stakeholders
• Do not attempt to optimize performance of specific pretreatment processes
• Select feedstocks (beyond stover) based on “Billion Ton”
study results
• Switchgrass
• Wheat straw
• Representative forest biomass feedstock
• Complements other activities in Biochemical Platform
• CAFI (broad reactivity screening as compared to specific pretreatment
process optimization)
• Exploratory Saccharification/Plant Cell Wall Deconstruction
• Sugar Processing Integration (platform for future integration of
feedstock/pretreatment/enzyme combinations)
Feedstock Qualification
Initial Findings on Switchgrass
Across Wide pH Range
% Xylan Solublized
• Standard methodology for
pretreatment and enzymatic
saccharification developed
• Initial data on switchgrass
generated
saccarification oligomers
saccarification monomers
pretreatment oligomers
pretreatment monomers
100
90
80
70
60
50
40
30
20
10
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( severity)
Neutral
( sev.)
Alkaline
( severity)
Sacharification oligomers
Sacharification monomers
Pretreatment oligomers
Pretreatment monomers
90
80
70
60
50
40
30
20
10
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Acidic
( severity)
15
0
Sand Baths for
Reactor Heating
MultiClave
10-Well
Reactor
% Glucan Solublized
Pretreatment conditions
100
Neut.
( sev)
Alkaline
( severity)
Integration of Leading Biomass
Pretreatments (CAFI 2)
• Objective: Develop comparative performance data and
process economics on selected leading pretreatment
approaches using:
•
•
•
•
Common feedstocks
Standardized enzymes
Identical procedures for sample analysis
Consistent methods for economic analyses, i.e., for material and energy
balancing and process cost estimation
• Build off of USDA-funded “CAFI 1” project into new areas
•
•
•
•
Corn stover and hybrid poplar feedstocks
Enzyme activities and loadings matched to pretreated feedstocks
Hydrolyzate fermentability at relevant sugar concentrations
Rigor of economic models (esp. pretreatment area capital costs)
• Generate “progressively” pretreated samples
• Facilitate core OBP R&D in the Exploratory Saccharification and Plant Cell
Wall Deconstruction subtasks
Integration of Leading Biomass
Pretreatments (CAFI 2)
AFEX
Dilute FlowHot
Acid through Water
ARP
1.75
Lime
75
Oligoxylose
Monoxylose
50
Oligoglucose
Monoglucose
25
MESP, $/gal EtOH
100
1.50
1.25
0
Pr
En etre
z. at.
Hy
d.
Pr
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En tre
z. at.
Hy
d.
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os
sib
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Sugar yields, % of max total -
Comparative Sugar Yields and Process Economics from “CAFI 1” Data
1.00
Dilute Acid Hot Water
AFEX
w/o Oligomer Credit
ARP
Lime
w/ Oligomer Credit
Initial Findings from “CAFI 2” Project
• Hybrid poplar is more difficult to effectively pretreat and saccharify
• Especially for alkaline pretreatments
• Commercial xylanase addition can result in higher xylose AND glucose
yields at same overall protein loading as “cellulase only” enzyme cocktail
• Especially for alkaline and neutral pretreatments
• Process modeling updates underway (initial milestone in June, 2006)
Enzyme Subcontract Liaison
• Objective: Support and validate enzyme cost reduction by
enzyme manufacturers (Novozymes and Genencor)
• Supply “standard” substrate (dilute acid pretreated corn stover, PCS)
• Develop cost metric to translate performance into economic terms, i.e.,
enzyme cost ($/gallon EtOH)
• Experimentally validate improved enzyme performance
• Review/Audit achievements in reducing enzyme production costs
• Contracts with two enzyme companies reduces risk
• Different approaches, different means of achieving cost reduction
• Improved enzyme production economics
• Improved specific activity
• NREL improvements to high solids, dilute acid pretreatment
process contributed to enzyme cost reduction
Pretreated Corn Stover (PCS)
Substrate Improvements
Improved Enzyme Preparation on
Pretreated Corn Stover (PCS)
Example SSF Performance Assay Results-- Improved Substrate
100
90
80
70
60
50
40
30
20
10
0
0
Improved PCS
Original PCS
Example SSF Performance Assay Results -- Improved Preparation
100
90
80
70
60
50
40
30
20
10
0
% Cellulose Conversion
% Cellulose Conversion
Enzyme Subcontract Liaison
10
20
30
40
50
60
70
Soluble Protein Loading (mg protein/g cellulose)
Benchmark prep
Improved prep
Benchmark prep
Improved prep
0
10
20
30
40
50
60
70
Soluble Protein Loading (mg protein/g cellulose)
• Enzyme Subcontract Liaison activities completed in FY05
• Verified reduction of cellulase costs to less the $0.20/gallon EtOH (per
enzyme cost metric) for both Novozymes and Genencor
• 20-30X improvement from starting benchmark
Enzymatic Hydrolysis
• Objective: Develop processing knowledge to enable high solids
enzymatic saccharification
• Understand impacts of background sugars and other inhibitors
• Characterize rheology and mixing characteristics of high solid slurries to
facilitate design of commercial equipment
• Identify commercial reactor systems and develop cost information
• Will test whole slurry conversion using advanced enzymes
• Evaluate solid phase properties during hydrolysis (particle size,
crystallinity, rheology, pore size distribution) and relate to kinetics
• Investigate fundamental factors affecting rheology
• Identify promising commercial reactor systems
Enzymatic Hydrolysis
High solids processing can significantly
reduce capital and operating costs
$1.12
Testing a High Solids Bioreactor (HSBR)
and comparing to fed batch solids
addition to a stirred tank bioreactor
$1.08
$1.06
$1.04
$1.02
$1.00
$0.98
$0.96
18%
20%
22%
24% 26%
28%
30%
32%
Total Solids to Saccharification (wt. %)
25% solids before hydrolysis begins
90%
Cellulose Conversion
MESP ($/gal)
$1.10
80%
70%
60%
50%
40%
30%
HSBR - 40 mg/g
20%
Shake Flask - 40 mg/g
HSBR - 20 mg/g
10%
Shake Flask - 20 mg/g
0%
0
24
48
72
96 120 144 168 192 216 240 264 288
Time (h)
Rheology and CFD Modeling—
Univ. Louisville
• Objective: Use Computational Fluid Dynamics (CFD)
modeling to improve design of pretreatment,
saccharification, and fermentation reactors
• High solids conditions
• Changes in insoluble solids level and slurry viscosity as pretreatment
and enzymatic hydrolysis reactions proceed
• Initial project investigated:
• Viscosity of biomass slurries
• CFD modeling of pretreatment reactors and stirred tank bioreactors
• Detoxification of pretreatment hydrolyzates (activated carbon)
• Current project focusing on:
• High solids enzymatic processing strategies
• CFD simulations of pretreatment/hydrolysis reactors
• Measurement of changes in rheological properties
Rheology and CFD Modeling—
Univ. Louisville
CFD Simulations of Stirred Tank
Bioreactor at Different Scales
CFD Simulations of High Solids
Pretreatment Reactor (Varying Screw
Conveyor Design)
Interrupted Flight Conveyor
Conical Bottom-Lift Conveyor
Interim Stage Gate Overview
• Most Recent Review:
• Pretreatment Core R&D Stage Gate Review
• June 9-10, 2005 (Golden, CO)
• Other Recent Relevant Reviews:
• May 2003 “Advanced Pretreatment” Interim Stage A Review
• May 2003 “Enzyme Sugar Platform” Interim Stage B Review
• November 2003 Office of the Biomass Program Peer Review
• May 2004 “Fundamentals and New Concepts” Interim Stage A
Review
• September 2004 “Sugar Processing Integration” Interim Stage B
Review
Interim Stage Gate Overview
• Pretreatment Core R&D Stage Gate Review
• Covered all 8 FY05 projects in Pretreatment Core R&D Area
• June 9-10, 2005 (Golden, CO)
• Reviewers:
• Academia
• Sharon Shoemaker – UC Davis
• Michael Penner – Oregon State University
• Industry
• Bob Wooley – Nature Works
• Pat Smith – Dow
• Government (DOE)
• Amy Miranda – Biomass Program (HQ)
• Andy Trenka – Biomass Program Project Management Center
(Golden)
• David Thomassen – Office of Science (HQ)
Reviewer Comments—
Overall Assessment
Strengths
• “Goals are relevant, realistic and well managed with stage gate disciplines.”
• “Focus on critical issues/challenges. Use of merit-based research. Strong
sense of team approach to problem solving.”
• “Great researchers, dedicated. Great facilities.”
Weaknesses
• “Too few resources due to too little funding. DOE is not aggressive enough to
terminate projects that don’t meet milestones.”
• “Funding inadequate. Not clear that major pilot scheduled for FY08 (?) will
have an adequate knowledge base from basic R&D to have the desired
impact or to contribute the desired progress.”
Suggested additions/deletions to improve the portfolio
• “Collaborations for the surface characterization group with academics (to
come up to speed fast) would be valuable.”
• “Collaborations with knowledgeable groups on the surface characterization
lab. Great facility, eager learners and smart people at NREL, but there are
experience knowledgeable people elsewhere too, who would love to help.”
Reviewer Comments—
Specific Projects
• Detailed, specific comments were provided to all 8
projects in the Pretreatment Core R&D area
• Will soon be available at
http://www.eere.energy.gov/biomass/progs/biogeneral/obp_gate/
pehindex.html
• Specific recommendation to focus on three key areas:
• Surface characterization
• High solids enzymatic saccharification
• Pretreatment and saccharification across feedstock categories
DOE Response
• Final review panel report from June, 2005 Pretreatment Core
R&D Interim Stage Gate Review recently received
• 45 pages, with scoring and specific comments on all 8 projects
• DOE response to reviewer comments is now underway
• Plan to have an official response document completed in
January, 2006
• FY06 AOP has been drafted with consideration to initial review
panel feedback
• A more focused plan in FY06:
• Surface characterization
• High solids enzyme saccharification
• Pretreatment and saccharification across feedstock categories
Summary and Future Work
Two projects completed in FY05 (no further work in FY06)
• Forest Biorefinery—Hemicellulose Extraction (as core
R&D activity)
• Enzyme Subcontract Liaison
FY06 Activities on Specific Projects
• Bridge to Corn Ethanol Project (Purdue/Aventine)
• Complete pilot testing of system with modified heat exchanger design
• Exploratory Saccharification Subtask
• Surface characterization: Evaluate lignin re-arrangement effects across
different pretreatment approaches (CAFI, Feedstock Qualification, also
Processing Integration Task samples)
• Enzyme augmentation studies: Effect of specific non-cellulase components
on CAFI and Feedstock Qualification pretreated samples
Summary and Future Work
FY06 Activities on Specific Projects (cont.)
• Integrate Leading Biomass Pretreatments (CAFI 2 Project)
• Pretreatment and saccharification studies on poplar feedstock
• Complete development of updated process economic models
• Feedstock Qualification
• Complete pretreatment pH and severity screening study of two feedstocks
(switchgrass, wheat straw)—ties to FY06 Joule milestone
• 3rd feedstock in FY07 (representative forest residue)
• Enzymatic Hydrolysis
• Continue to develop high solids saccharification (includes advancing
rheology and reactor design studies)
• Test advanced cellulase preparations under process relevant conditions
(high solids, background sugars, hydrolyzate inhibitors)
• Rheology and CFD Modeling Project (Univ. Louisville)
• CFD simulations of high solids pretreatment and saccharification reactor
designs