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12th Diesel Engine-Efficiency and Emissions Research Conference
Eaton Aftertreatment System (EAS) for On-Eaton Aftertreatment System (EAS) for On-Highway Diesel EnginesHighway Diesel Engines
Haoran Hu
Eaton Corporation August 22, 2006
© 2004 Eaton Corporation. All rights reserved.
Agenda
¾Challenges and Opportunities ¾ The Development of Eaton Aftertreatment
System (EAS) ¾Summary
US 2010 US 2007
US 2004
EU 5
JA 2005
Evolution of ON-Highway Emissions Regulations
Challenges and Opportunities: ¾ SCR Catalysts Requires Urea Supply Infrastructure, which Is Unlikely to be Available
for North America Market by 2009
¾ NOx Absorber (LNT) System has Higher Fuel Penalty and Durability Concerns
¾ A New Aftertreatment System Is Required
Challenges of Stringent Diesel EngineEmissions Regulations
¾ Aftertreatment Systems Are Required to Meet 2010 Ultra-low NOx Requirements
¾ Most Probable Solutions: • Urea SCR Catalysts • NOx Adsorber (LNT)
Catalysts 0 2 31
NO x g kW -1h -1
0
0.02
0.04
0.06
0.08
0.10
0.12
0.14
Part
icul
ates
g k
W-1
h -1
rtreatm ent S ystem
DPF
EG R
0
Eaton Afte
Ea
2 31
NO x g kW -1h-1
0
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.02
0.04
0.06
0.08
0.10
0.12
0.14
Part
icul
ates
g k
W-1
h-1
ton Aftertreatm ent
System
DPF
EG RU S 2010 U S 2007
U S 2004
EU 5
JA 2005
Eaton’s Innovative Solution
• NH3 Generated during Fuel Rich Regeneration Process
• Urea Is Converted into NH3 • SCR Needs NH3, not Urea
Engine Out
LNT
Urea SCR
Features: ¾ Fuel Reformer Converts HC to H2/CO During LNT Regeneration ¾ LNT Produces Ammonia During Regeneration ¾ SCR Catalyst Stores and Uses Ammonia for Further NOx Reduction ¾ Reduced Catalyst Volume and Cost ¾ Synergistic Use of LNT/SCR Catalysts ¾ Improved Durability
Eaton Aftertreatment System (EAS)
LNT NH3 SCR
Fuel Reformer
Engine out
SCR out
Chemical Kinetic Mechanism of Eaton Aftertreatment System
4 NO + 4 NH3 + O2 = 4 N2 + 6 H2O
6 NO2 + 8 NH3 = 7 N2 + 12 H2O
NO + NO2 + 2 NH3 = 2 N2 + 3 H20 SCR Catalyst
NOx NH3 O2
N2
H2O SCR
LNT
NO + ½O2 = NO2
BaO + NO2 + ½O2= Ba(NO3)2
Trapping (lean)NO
O2
O2NO2 LNT Catalyst
Regeneration (rich)
LNT Catalyst CH
H2
CO N2
CO2 NH3
Ba(NO3)2 = BaO + 2NO + 1½O2
NO + CO = ½N2 + CO2
5/2H2 + NO = NH3 + H2O
Chemical kinetic Mechanism
Fuel Reformer Catalyst H2O
CH O2
CO
H2
CH4 + ½O2 = CO + 2H2
CO + H2O = CO2 + H2
Fuel Reformer
NO
x (p
pm)
Developed Chemical Kinetic Models forSystem Simulation
Sample LNT Simulation Sample SCR Simulation 1000
400 1000 Exp NOx at SCR Inlet
Simulation 900 Exp NOx at SCR Outlet
Experiment 800 Sim NOx at SCR Inlet
300 750
NH
3 (p
pm)
NO
x [p
pm]
Sim NOx at SCR Outlet 700
600
500
400
200 500
100 250 300
200
0 0 100
60 80 100 120 140 0 0 500 1000 1500 2000 time (sec) Time [sec]
Fully Transient Kinetic Models:
¾ Kinetic Mechanisms (21 reactions) Are the Result of Extensive Research ¾ Calibrated Kinetic Parameters With Engine Test Data ¾ Excellent Tool for Catalyst Development and System Simulation
Two Fully Equipped EngineDynamometers for Development
flow
LNT
Desulfation Development
– CAT C9 2004 ACERT Engine • 350 hp @ 2300 rpm
– Reformer+LNT+SCR – Fuel Dosing System – Emission Measurement Benches
Performance Development
– DDC S60 14L Engine • 500 hp @ 2100 rpm
– Reformer +LNT +SCR – Fuel Dosing System – Emission Measurement Benches
LNT NH3 SCR
Fuel Reformer
Engine out
SCR out
NO
x C
once
ntra
tion
(ppm
)
Excellent NOx Reduction Efficiency atSteady State Test Modes
8 0 0 2 0 0 0 C 1 0 0 A ve ra g e N O x E ffic ie n c ie s L N T : 7 4 % , S C R : 4 4 % , S ys te m : 8 5 %
7 0 0 1 5 0 0
6 0 0 1 0 0 0
L N T N H 3 O u t R e fo rm e r 5 0 0 5 0 0 F u e lin g
4 0 0 0 S C R N H 3 O u t
N O x E n g O u t 3 0 0 12 .9 g /c y c le -5 0 0
2 0 0 -1 0 0 0 N O x L N T O u t N O x S C R O u t
3 .4 g /cy c le 1 .9 g /c yc le 1 0 0 -1 5 0 0
0 -2 0 0 0 5 0 0 5 5 0 6 0 0 6 5 0 7 0 0 7 5 0 8 0 0 8 5 0 9 0 0 9 5 0 1 0 0 0
T im e (s )
NH
3, p
pm a
nd F
uelin
g, g
ram
s/m
in
Engine Dyno Steady-state C100 Mode: ¾ Demonstrated the Effectiveness of NOx Reductions in Both Total NOx Conversions and
NOx Spikes (up to 50%) Reduction
¾ NH3 Generated During LNT Regeneration and Can Be Stored in SCR Catalyst for NOx Reduction
¾ SCR Can Contribute up to 20% NOx Reduction Relative to Engine Out NOx
Demonstrated NOx Reductions With 13-mode Steady State Test
NO
x co
ncen
trat
ion
(ppm
)
1000
13 Mode Average NOx Efficiencies 900 LNT: 72%, SCR : 32%, System: 81%
800 E ngine-out N O x L N T out N O x 700 SC R out N O x
600
500
400
300
200
100
0 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 1680 1800 1920
T im e (sec) W R 2227D 2
Engine Dyno 13 Mode Steady-state Tests: ¾ Over 80% NOx Efficiency, Less Than 4% Fuel Penalty for MY 2004 HD Diesel Engines, and
Around 2% Fuel Penalty for 2007 Compliant Engines ¾ Significant Reduction in NOx Spikes ¾ Fuel Reformer Improves Catalyst Performance at Lower Temperature
Less Frequent Desulfation and ImprovedLNT Durability
0
0.2
0.4
0.6
0.8
1
1.2
10 20 30 40 50 60 70 80 90 100
Desulfation Interval - (Hours)
BSN
Ox
- gm
/HP-
HR
US ‘010 NTE
LNT Only LNT + SCR
~30% Reduction in Desulfation Frequency
LNT Durability Improvement by Less Frequent Desulfation:
¾ SCR NOx Reduction Compensates for Loss in LNT Performance Due to Fuel Sulfur Poisoning.
¾ Less Frequent Desulfation is Required Comparing With LNT Only Systems ¾ Improved LNT Durability by Up to 30% Due to Less Frequent Desulfation
–––––
SCR
LNT
Fuel Reformer Fuel Doser
¾ Freightliner Century Class Truck
¾ 2004 DDC S60 Engine
¾ Real-time NOx Conversions in Targeted Range
¾ Parameters Measured Include: Exhaust NOx & O2 (6 positions) Exhaust Flow Rate (2 positions) Exhaust Temp & Pressure (6 positions) Engine Parameters via J1587 Engine EGR and VNT Positions
System Performance and Integration on VehicleRoad Test
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
9:44:38 9:46:05 9:47:31 9:48:58 9:50:24 9:51:50 9:53:17 9:54:43
Time
NO
x Ef
ficie
ncy
0
50
100
150
200
250
300
350
Simulated System Size and Packaging with 2010 NOx Compliant Performance
40
50
60
70
80
90
100
1 1.5 2 2.5 3 3.5 4
(LNT+SCR) Volume divided by ESV
NOx
Conv
ersi
on E
ffici
ency
2010 NOx Compliant
Lower cost & size Higher cost & size
‘Optimized Baseline’
Based on system simulation w/ USEPA 2007 compliant engine
More Space-Efficient Than Urea BasedSCR System
Eaton Aftertreatment: LNT + SCR volume: 2x ESV (engine swept volume)
Reformer catalyst: 0.5x ESV DPF: 1.5 – 2.0x ESV TOTAL SYSTEM VOLUME: 4.0 - 4.5 x ESV
Eaton Aftertreatment System
Fuel Reformer
Fuel Doser
Engine
SCR
DPF
LNT NH3
Typical Urea SCR SystemUREA SCR: SCR catalyst: 2.5x – 3.5x ESV Hydrolysis catalyst: 0.5 x ESV DOC: 0.5 x ESV DPF: 1.5 – 2.0x ESV TOTAL SYSTEM VOLUME: 5.0 – 6.5x ESV + 4.0 – 6.0 x ESV urea tank volume
SCR
Urea Doser
Hydrolysis catalyst
Engine
SCR
Fuel Doser
DPF
Urea Tank
Fue
Urea Doser
Hydrolysis catalyst
Engine
l Doser
DPF
Urea Tank
Good for the Environment and Superior Value for Our Customers
Eaton Aftertreatment System
Fuel Reformer
Engine
�No Urea Required �Simple, Convenient in Operation �Smaller Package Size �No Weight Penalty �Single Dosing System
Typical Urea SCR System
�Urea Infrastructure Investment Required �Driver Intervention Required � Tankage/Weight Penalty Required �Penalty for “Failure to Fill” Required �Dual Dosing Systems Likely �Urea Price Volatility
Fuel Doser
SCR
DPF
LNT NH3
SCR
Urea Doser
Hydrolysis catalyst
Engine
Fuel Doser
DPF
Urea Tank
Eaton Aftertreatment SystemSummary
¾ A New Pathway to Utilize SCR Catalysts for NOx Reduction Without the Need of Urea Infrastructure
¾ An Innovative Method to Mitigate LNT Durability Concerns ¾ Demonstrated Technical Feasibility for Meeting 2010 Emissions
Regulations • Achieved Over 80% NOx Reduction Over 13-mode SET Test With Less
Than 4% Fuel Penalty for MY 2004 HD Diesel Engines, and Around 2% Fuel Penalty for 2007 Compliant Engines
• Developed and Validated Chemical Kinetic Models For System Modeling and Simulation
• H2 Generated By Fuel Reformer Improves LNT Regeneration and Desulfation Performance
• Developed Control Strategies for System Performance Optimization • Gained Experience in Desulfation, Package, Installation and System
Integration • Demonstrated NOx Reductions and LNT Regeneration During On-road
Driving Conditions
12th Diesel Engine-Efficiency and Emissions Research Conference
Questions?
Acknowledgement: The author would like to thank Eaton Corporation for its permission to publish this work, and would like to acknowledge the supports of Eaton Aftertreatment Team.
Contact: HaoranHu@Eaton.com
© 2004 Eaton Corporation. All rights reserved.
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