fuels research, testing, and standards · 2012. 6. 4. · fuels research, testing, ... •flex fuel...
TRANSCRIPT
NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy operated by the Alliance for Sustainable Energy, LLC
NBTRP 2012 Meeting
06-07 June 2012
Bob McCormick Task Leader,
Advanced Biofuels Performance R&D
Fuels Research, Testing, and Standards
Biofuels for Advancing America
Outline
• Why fuels performance R&D?
• Some past projects
• Ongoing research
• Future challenges
National Renewable Energy Laboratory Innovation for Our Energy Future 2
Relevance
3
Objective: Solve technical problems that are preventing expanded markets for current and future biofuels and biofuel blends
Research at the interface of fuel
production and engines and infrastructure
Photo: Aaron Williams, NREL
Photo: Aaron Williams, NREL
PIX
13
53
1
PIX 07265 PIX 08432
PIX 10590
National Renewable Energy Laboratory Innovation for Our Energy Future
National Renewable Energy Laboratory Innovation for Our Energy Future 4
Unleaded Gas1980s
500 ppm S Diesel1993
ULSD 2008-now
Issues with E15 2013+
?
NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy operated by the Alliance for Sustainable Energy, LLC
Past Projects and Accomplishments
Ethanol Research
• E15 Waiver Support
• With ORNL led DOE research on
E15 compatibility with cars and
impact on emissions
• E15 approved by EPA for 2001
and newer vehicles
• Flex Fuel ASTM Standard
Development (E85)
• Quality surveys pointed to issue
• Led to changes to ASTM specs
• E85 Emission Effects
• E15 Dispenser Retrofit
6
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
NO
x(g
/mi)
Composite NOxE0 E15
0 | 68 | 90 | FUL 0 | 60 | 90 | FUL RE0 RE15
ETCHO68 ETCHO69
Test Fuel
Test MilesRoad FuelVehicle
National Renewable Energy Laboratory Innovation for Our Energy Future
Biodiesel Research
• Quality test method development
and surveys
• Research leading to ASTM
specification for oxidation
stability
• Leadership of CRC workgroup on
cold soak filterability – leading to
B5 and B6-B20 ASTM standards
• Effect of metal impurities on
emission control catalyst
durability
• Algal FAME properties
• Partially funded by NBB under
multi-year, multi-million dollar
CRADA
7 National Renewable Energy Laboratory Innovation for Our Energy Future
Cloud Point, oC
-30 -25 -20 -15 -10 -5 0
CF
PP
or
LT
FT
, oC
-30
-25
-20
-15
-10
-5
0
CFPP vs CP
LTFT vs CP
TF
#5 (
Hig
h C
SF
T B
20)
TF
#2 (
Hig
h C
SF
T B
5)
NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy operated by the Alliance for Sustainable Energy, LLC
Ongoing Research
Metabolic Production of Fuel Molecules
9 National Renewable Energy Laboratory Innovation for Our Energy Future
Biomass-derived
sugars
• Only 4 biochemical pathways produce fuel “sized” molecules
• Yet this is thousands of possible compounds
• Which ones would be good fuels?
Collaboration with J.
Craig Venter Institute
precursor
metabolites
Metabolic Engineering + Hydrogenation
Hydrogenation collapses benzenoid and isoprenoid
classes to only a few potential fuel products
10
Hydrogenation Products
Fats
National Renewable Energy Laboratory Innovation for Our Energy Future
Biodiesel and long chain
hydrocarbons/alcohols
Isoprenoids
Benzenoids
Performance of Hydrocarbon Renewable Diesel Fuels
• Commercial and prototype fuels – 10 samples from industry partners
–Produced by hydroisomerization and
fermentation
• High quality, high cetane number
materials – Low level of residual oxygen in
some samples
• Fat/veg oil derived fuels are highly
isomerized (85%+)
11 National Renewable Energy Laboratory Innovation for Our Energy Future
Isoprenoid-Derived
Volume Percent Oxygenate
0 5 10 15 20
An
ti-K
no
ck
In
de
x (
R+
M/2
)
81
82
83
84
85
86
87
88
isopropanol
1-propanol
1-butanol
2-butanol
isobutanol
1-pentanol
isopentanol
ethanol
87 Minimum
Cellulose-Derived Oxygenates • Assess performance of oxygenates
in gasoline and diesel fuel
– Alcohols to C5 and cellulose/hemicellulose-
derived oxygenates (including mixed
alcohols)
– Isobutanol, 2-butanol, DMF, and 2-MF
exhibited high octane numbers
National Renewable Energy Laboratory Innovation for Our Energy Future 12
Volume Percent Oxygenate
0 5 10 15 20
An
ti-K
no
ck
In
de
x (
R+
M/2
)
81
82
83
84
85
86
87
88
isopropanol
1-propanol
1-butanol
2-butanol
isobutanol
1-pentanol
isopentanol
ethanol
87 Minimum
New Fuels in an Ethanol BOB World
13
•Refiners make sub-octane
hydrocarbon blendstock
•Blendstock for Oxygenate
Blending (BOB)
•Meets AKI requirement when
ethanol is added
•Butanol, for example, may not be
high enough octane
•But butanol can lower the RVP of
ethanol blends
• Is there an optimal combination
considering gasoline blending
economics?
National Renewable Energy Laboratory Innovation for Our Energy Future
Alcohol-Gasoline Water Interaction
• C2 to C5 alcohols blended in gasoline at 3.7 wt% oxygen • Level allowed by EPA waivers to the substantially similar rule
• 25 ml exposed to 2.5 ml of water at room temperature • Shaken to mix
• Analysis of gasoline and water phases by GC
14
2.5 ml DI water
25 ml Gasoline
(BOB) +
Alcohol at 3.7%
Oxygen
National Renewable Energy Laboratory Innovation for Our Energy Future
Ethanol
1-Pro
panol
2-Pro
panol
1-Buta
nol
2-Buta
nol
Isobuta
nol
1-Penta
nol
Isopenta
nol
Ethyl
levu
linate
Butyl l
evulin
ate
MTHF
Meth
yl p
entanoate
Meth
yl le
vulin
ate MF
DMF
We
igh
t P
erc
en
t O
xyg
en
Rem
ain
ing
1.5
2.0
2.5
3.0
3.5
4.0
Alcohols: 3.7% Oxygen in Gasoline Initially
Others: 2.7% Oxygen in Gasoline Initially
AlcoholsOther Oxygenates
Biodiesel in Cold Weather: Monoglyceride Polymorphism
• Polymorphic phase conversion can occur upon heating or at constant temperature
• Light scattering shows new crystal formation on heating – characteristic of
polymorphism
• Obvious crystal habit change is occurring
• DSC and X-ray analysis of isolated crystals at room temperature match ß-form
• FMT used as parameter in subsequent work
Initial crystals formed Crystals after heating or
standing at RT
0
50
100
150
200
250
0 10 20 30 40 50 60
Sig
na
l
Temperature °C
0.6% Monostearin in Animal B100-FMT
Final Melting
Temperature (FMT)
Chupka, G.M., Yanowitz, J., Chiu, G., Alleman, T.L., McCormick, R.L. Energy & Fuels 25 398–405 (2011)
10X magnification
Measurement bar = 250µm
Experimental Monostearin Solubility Diagram
Temperature, oC
0 5 10 15 20 25 30 35
wt%
Mo
no
ste
ari
n
0.00
0.05
0.10
0.15
0.20
0.25
16 ppm Water
157 ppm Water (as received)
750 ppm Water
CP
FMT
Monopalmitin (Selvidge, 2007)
β-monostearin solubility in distilled soy B100
NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy operated by the Alliance for Sustainable Energy, LLC
Future Challenges
What is the definition of drop-in fuel?
• Compatible with engines
• Compatible with fuel distribution and
refueling infrastructure
• Fungible (interchangeable)
• B5 biodiesel may be approaching drop-in
• What about isobutanol?
• What about low levels of oxygen in biomass-
derived hydrocarbons?
National Renewable Energy Laboratory Innovation for Our Energy Future 18
Ligno-Cellulosic Biomass
19
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
O H
O
H O
H 3
C O
O H
O C H 3
O C H 3
O
O
O
O H
O C H 3
O C H 3
H 3 C O
O O
H O
H 3
C O
H O
O C H 3
O C H 3
O H
O
H O
H 3
C O
O H
O C H 3
O C H 3
O
O
O H
O C H 3
O C H 3
O C H 3
O
O
O
O H
H O
O
O
O
O
O H
H O
O H
O H
O
O
O
O H
H O
O H
O H
O
O
O
O H
H O
O H
O H
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
O
O
O
O H
O H
O H
H O
H O
O H O
National Renewable Energy Laboratory Innovation for Our Energy Future
Lignin: 15%–25%
Hemicellulose: 23%–32%
Cellulose: 38%–50%
• Biomass has high oxygen
content: • 40 to 60 wt%
• Molar O/C about 0.6
• Economically rejecting this
oxygen may not be possible
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
0 2 4 6 8 10 12 14 16 18 20
Up
grad
ing
Co
st (
$/g
ge)
Oxygen Content in Final Product (wt%)
Economic evaluation of biomass pyrolysis oil upgrading costs as a function of final product oxygen content
Arbogast, S.V. Upgrading Requirements for the Transport and Processing of Pyrolysis Oil in Conventional
Petroleum Refineries, Houston, TX: Global Energy Management Institute, 2009.
Can Oxygenate Be Tolerated in Drop-in Fuel?
• Article of faith that “drop-in” fuels are hydrocarbon
• But biomass has a high oxygen content
• Many conversion processes produce oxygenates
– Biochemical to sugar/fermentation
– Thermochemical mixed alcohol
– Acid hydrolysis
– Lignin depolymerization
– Fast pyrolysis
20 National Renewable Energy Laboratory Innovation for Our Energy Future
Determine if and at what levels biomass-
derived oxygenates are scientifically and
commercially feasible in drop-in fuels
Evaluation of Cellulosic Biomass-Derived
Oxygenates as Drop-In Fuel Blend Components
• DOE-OVT project initiated Q3
FY12
• Oxygenate blend components
and residues
– Measurement of Oxygenate and
Fuel Blend Physical and
Performance Properties
– Infrastructure Compatibility
– Storage and Handling
– Engine Performance Evaluation
– Techno-Economic Analysis
National Renewable Energy Laboratory Innovation for Our Energy Future 21
Compound Molecular Structure
Isobutyl
alcohol
Methyl
pentanoate
Pentyl
pentanoate
2-Methyl
furan
Dimethyl
furan
Methyl
tetrahydro
furan
Cresols
Xylenols
Guaiacol
Methyl
anisoles
OHOH OH
OHOH
OHOH
OH
OH
Ble
nd
Co
mp
on
en
ts
Re
sid
ue
s
National Renewable Energy Laboratory Innovation for Our Energy Future 22
Improved acid titration
gives multiple endpoints
HPLC method
identifies acids
• Pyrolysis oil hydrotreated to different
levels of oxygen content
• Distilled to various boiling fractions
• Hydrogenation drives oxygen to phenolic
form
• Developed improved approach to acid
characterization
• Differentiate weak and strong acids
Characterization of Acids in Hydrotreated Pyrolysis Products
8.2% 4.9% 0.4%
Marketplace for Renewable Fuels
National Renewable Energy Laboratory Innovation for Our Energy Future 23
Need to Create Market
Demand for Cellulosic Ethanol
• E10 - saturated with corn
ethanol
• E15 - EPA approved for some
cars but not implemented in the
field
• E85 – flex fuel vehicles grew
but fuel at the stations never
materialized
Conventional (Starch) Ethanol Biodiesel Cellulosic Ethanol Other Advanced Biofuels
Energy Security Strategies for Transportation
• Biofuels
• Natural gas
• Electricity
• Hydrogen
National Renewable Energy Laboratory Innovation for Our Energy Future 24
Petroleum
Displacement
Energy Efficiency • Engine efficiency
• Advanced combustion
and engine design
• Lubricants
• Reduced penalty for
emission control
• Vehicle efficiency
Fuels That Enable
Efficient Engines
Ethanol Can Enable More Efficient Engines
National Renewable Energy Laboratory Innovation for Our Energy Future 25
•Higher compression ratio
yields higher efficiency
•Above CR of 14 piston ring
friction dominates
•CR=14 is optimal
•Current engine CR about 10
Higher CR would be enabled by
HIGHER Octane Number • Ethanol has a much higher blending Octane
Number than hydrocarbon blendstocks
• Another advantage of ethanol is cooling effect of
vaporization – much greater than hydrocarbon
Opportunity: Dramatic Increase in CAFE Standards
• Average 54.5 mpg
• Will require downsized, turbocharged, direct injection
gasoline engines with higher compression ratio
• Octane number will need to be significantly higher, 95-
100 RON
– Blending of ethanol requires less RON because of cooling
effect of vaporization
– Making higher ethanol blends (E25 to E30) may be highly
attractive economically
– Future hydrocarbon fuels will also have to meet higher
RON requirements
• Research to define potential efficiency improvement for
ethanol and hydrocarbon fuels with increased RON
National Renewable Energy Laboratory Innovation for Our Energy Future 26
Questions ?
Discussion ?
National Renewable Energy Laboratory Innovation for Our Energy Future 27
Flex Fuel Blends (E85) Survey and Specification Changes
• Worked with CRC to assess fuel
quality nationwide
• Prior survey showed high failure
for rate RVP
– Vapor pressure is critical for cold
starting and driveability
– Anecdotal reports of difficulty starting
and poor performance
• Led to changes to ASTM D5798
– To allow higher levels of gasoline,
increasing vapor pressure
• New survey showed that FFV
drivers will see improved
performance
• Survey of 106 samples
• All three volatility classes
• Nearly 50% of samples met vapor
pressure requirements
• A marked improvement over
previous surveys National 2010-2011 Survey of E85: CRC
Project E-85-2 http://www.nrel.gov/docs/fy12osti/52905.pdf
28 National Renewable Energy Laboratory Innovation for Our Energy Future
B20 Bus NOx Comparison
0
10
20
30
40
50
1998 2005 2008 2008 Hybrid 2010 2011
NO
x Em
issi
on
s (g
/mil
e)
Bus Engine Build Year
NOx emissions with 95% confidence
interval bars; 3 dyno runs each
Cert
Cert B20
0.0
0.5
1.0
1.5
2.0
2010 2011
0
1
2
3
4
5
6
7
8
9
10
Cold Start Hot 1 Hot 2 Hot 3 Hot 4 Hot 5 Hot 6 Hot 7 Hot 8 Hot 9
Gra
ms
per
Mile
NO
x
Observed "Warm Up" or adaptation of SCR w/MAN20 minute soak between test runs
MAN Cert
MAN B20 Cert
MAN B100
Photo: Mike Lammert, NREL
National Renewable Energy Laboratory Innovation for Our Energy Future 29
•Buses tested on NREL’s
ReFUEL laboratory HD chassis
dynamometer
•B20 effect on NOx statistically
significant in fewer than half of
comparisons
•Note near-zero NOx for 2010-
2011 buses with SCR • SCR eliminates B20 and B100 effect
on NOx emissions
Biodiesel Catalyst Durability Study
• Accelerated aging of LD diesel catalysts
• 2011 Ford F250 with DOC+SCR+DPF
• Ultralow sulfur diesel, B20+Na, B20+K and B20+Ca
• After 150,000 miles equivalent exposure, no
significant emission degradation was observed
• Biodiesel metals at current spec limit appear to
have no negative effect on LD catalyst durability
Used catalysts being
characterized by
ORNL and Ford
Photo: Aaron Williams, NREL
Photo: Aaron Williams, NREL
Photo: Aaron Williams, NREL
30 National Renewable Energy Laboratory Innovation for Our Energy Future
Sample ID
Gly
ce
rid
es,
wt%
, D
65
84
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
Monoglycerides
Diglycerides
Triglycerides
Note all samples meet D6751-11a limit for total glycerin (0.240 wt%)
2011 Wintertime B100 Survey
• Completion of B100 producer
quality survey (samples obtained
from 53 producers)
• 2011 had highest ever production
volume of B100 in the US: 1.1
billion gallons
• B100 almost always meets the
quality specifications, a marked
improvement over previous
surveys
– 4% failure on oxidation stability
– Less than 2% failure on cold
soak filterability, metals, and
flashpoint
– No failures on glycerin or acid
value Sample ID
Oxid
ation S
tabili
ty,
hrs
, E
N1575
1
0
5
10
15
20
25
30
35
D6751-11a Minimum Oxidation Stability, 3 hrs
Sample ID
Oxid
ation S
tabili
ty,
hrs
, E
N1575
1
0
5
10
15
20
25
30
35
D6751-11a Minimum Oxidation Stability, 3 hrs
31 National Renewable Energy Laboratory Innovation for Our Energy Future