Small Scale Continuous Biomass
Pretreatment Reactor Development:
A Case Study Dale Monceaux1 and Richard C. Agar, AdvanceBio, LLC, Milford, OH, USA
2013 BIO World Congress on Industrial Biotechnology
June 16-19, 2013 Montréal, Canada
• Company intro
• Feedstock characterization
• Technology scaleup
• Pretreatment reactor design
• Learnings
AdvanceBio
AdvanceBio, LLC
• Formed in 2007
• Provide technology, engineering
and process design services for first
generation starch and sugar based
ethanol production.
• Provide consulting services in
support of project development.
• Consult and provide services
related to first and second
generation biofuels and.
• Application of process simulation
modeling of ethanol plants to
support efficiency and technology
upgrades and capacity expansion.
AdvanceBio Systems,
LLC
• Formed in 2009
• Exclusive rights to IP related to the
mechanical design of biomass
processing equipment used in the
pulp & paper and biomass to
chemicals at capacities to 700 bdtp
• Scaled the process down to meet
the immediate needs of the current
market.
• Design, engineer, fabricate and
supply biomass pretreatment
reactors and ancillary equipment.
• Provide design, engineering and
fabrication of small scale skid-
mounted process equipment based
on non-ABS IP.
AdvanceBio
• Core group of technologists and engineers
with each with over 30 years of development,
design and operations experience
• Technology development and consulting
services for biofuels and biochemicals projects
– Conventional
• starch and sugar
• plant capacities up to 100 mm gpy
– Advanced
• lignocellulosic
ENZYME
PROD
FEEDSTOCK
SIZE
REDUCTION
Context for Pretreatment
CONDITION
PRETREAT
FERMENT
SACCHARIFY
IMPREGNATE
FEEDSTOCK
CLEANING
RESIDUAL
PRODUCT
RECOVERY
FEEDSTOCK
PROD &
HARVEST
Pretreatment has a
central role and
pervasive impact on
all other processes
How to Reduce Uncertainty/Risk
•Successive scale-up to bench, pilot, modules,
demonstration processes before commercial
plant – historical industrial approach
– Provides data valued by investors
– Time consuming
– Costly
– Private investors reluctant to incur costs, risks, long
time horizons
5
Feedstock Bulk Density
6
720
Developmental Scale Equipment
Overall Glucose and Xylose Yields
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 20 40 60 80 100 120
Pretreatment time (min)
Yie
ld (
% o
f o
rig
ina
l g
luco
se +
xy
lose
)
Maximum potential glucose
Maximum potential xylose
8
Combined
Glucose in
Stage 1
Xylose in
Stage 2
Maximum glucose yield – even more
challenging for low enzyme loadings
Maximum xylose yield
Maximum total yield
Dilute Acid Pretreatment and Subsequent Enzymatic Hydrolysis
160oC with 0.49% H2SO4
Design Basis Considerations
–Reaction Chemistry – Catalyst
–Reaction Conditions • Time
• Temperature / Pressure
–Liquid Solids Ratio
–Bulk Density
–Feedstock Composition
–Conversion Efficiencies
–Plant Capacity
9
Reactor Volumetric Capacity
10
per 10 minutes of residence at 50% active volume per 100 mm lpy of Ethanol
Bagasse
CornStover
WheatStraw
RiceStraw
Reed
Bamboo
Hardwood
So wood
750 800 850 900 950 1,000
ODtpd
Thermal Conductivity
11
Scaleup………Scaledown
12
VISUALIZE
DESIGN
Commercial Scale Biomass to Sugars
13
Sugarcane Bagasse
14
Commercial Reactors for Making Furfural
15
Commerical-Scale Process
AdvanceBio Reactor Design Basis Criteria
•Continuous feed and discharge
•Temperature control (pressure)
•Time control
•Feedstock flexibility
•High solids
•Catalyst flexibility
Reactor Metallurgy
•Metals-
– High pH
• Carbon steel
• 304
• 316
– Low pH
• Alloy 825
• Alloy C-276
• Monel® 400
• Zirconium
•Commercial
– Corrosion rate
– Erosion
– Cost
•Research
– Corrosion
– Cost
18
Operating
Life
Scope of Supply
By AdvanceBio
• Feedstock flow control
mechanism
• Reactor
– Feedstock flexibility
– Chemistry flexibility
– Residence time control
– Temperature control
• Discharge mechanism
• Flash separation
• Steam generation capacity
• Control system
• Mobile skid package
By Owner
• Boiler feedwater
• Instrument air
• Electricity
• Catalyst
• Feedstock
• Process conditions
Design Basis Criteria
• Nominal Capacity: 10 dry kg/hr at 10 minutes
retention
• Raw Material: Shredded biomass – Length: Less than 12 mm
• Reaction Conditions: – Retention Time: 2.0 to 60 minutes
– Operating Temperature: Typical 120° to 190°C
– Operating Pressure: 11.5 bar at 190°C
– Catalyst Chemical: Mixed with solids before feeding
– Design Feedstock Density: Typical 80 dry kg/m3
Bench Scale Pretreatment Reactor
Small Scale System
Mechanical
Considerations
22
Biomass Bulk Density Variability
4.2
4.3
4.4
4.5
4.6
4.7
4.8
4.9
5
5.1
3.4 27.0 216.0 729.0
Bu
lk D
en
sit
y
(lb
/ft3
)
Container Size (in3)
3.0 30.0 300
Corrosion - Errosion
Other Learnings
•Catalyst feed rates at ultra-low
throughput rates are not conducive to
continuous feed and good distribution.
•Apparent minor changes in equipment
can have a significant impact on the
overall design and fabrication schedule.
• “Standard design” will generally require
custom features.
•The direction of research groups will
change. 25
Generation 2 Bench Reactor
26
Lab Scale Reactor
27
Future…
• Continue to focus on optimizing the design and
fabrication of bench, lab and pilot units with
learnings transferable to commercial systems.
• Currently working on non-liquid catalyst recovery
systems.
• Providing small, self-contained equipment skids for
process technologies other than biomass
pretreatment.
• Developing reactors optimized for producing,
furfural, etc.
28