9. Symposium Steuerungssysteme für automobile Antriebe Berlin, September 21st, 2012 SCR System of the Future; From Complex Hardware to SCR Functions Jean-François Zebo; Emitec SAS
9. Symposium Steuerungssysteme für automobile AntriebeBerlin, September 21st, 2012
SCR System of the Future;From Complex Hardware to SCR Functions
Jean-François Zebo; Emitec SAS
Agenda
• Introduction
• Challenges to Achieve High Efficient SCR
• Components of SCR System; Hardware
- Dosing System
- SCR Injector
- SCR Controller and Sensors
- SCR Catalyst System
• Limitations and Optimization of Dosing Control on SCR Efficiency
• OBD side of SCR
• Close Coupled SCR System; Practical Test Results
• Conclusion
Heavy Duty /NRMM – Emission Standards (ETC) & -Technology Shift of Priorities
PM
[m
g/k
Wh
]
NOx [g/kWh]1
60
30
42 6
EU V EU IV
03
Engine TechnologyEU VI; NRMM >130 kW Stage 3 B
NRMM EUStage IV
SCR 80 % NRMMStage IIIB(2012)
NRMM EU IIIB
SCR 80 % EU VI
Heavy Duty /NRMM – Emission Standards (ETC) & -Technology Shift of Priorities
PM
[m
g/k
Wh
]
NOx [g/kWh]1
60
30
42 6
EU V EU IV
03
Engine TechnologyEU VI; NRMM >130 kW Stage 3 B
NRMM EUStage IV
SCR 80 % NRMMStage IIIB(2012)
NRMM EU IIIB
EU VI
Heavy Duty /NRMM – Emission Standards (ETC) & -Technology Shift of Priorities
PM
[m
g/k
Wh
]
NOx [g/kWh]1
60
30
42 6
EU V EU IV
EU VI
03
Engine TechnologyEU VI; NRMM >130 kW Stage 3 B
NRMM EUStage IV
NRMM EU IIIB
SCR >92 -95 %
Agenda
• Introduction
• Challenges to Achieve High Efficient SCR
• Components of SCR System; Hardware
- Dosing System
- SCR Injector
- SCR Controller and Sensors
- SCR Catalyst System
• Limitations and Optimization of Dosing Control on SCR Efficiency
• OBD side of SCR
• Close Coupled SCR System; Practical Test Results
• Conclusion
High Efficient SCRTechnolgyη.NH3 > 94 %
Advanced DOC Technology
OptimizedNH3 Slip Catalyst
Perfect Mixing of NH3 with Exhaust Gas
UI.NH3 > 0,98
SCR Catalyst Technoloy
Robust AdBlue-Injection
Excellent Decompostion of Reduction Agent
Minimum HNCO concentration
10110100 10110100
10110100 01010101
01001010 01001010
01010100 01001010
Advanced Dosing Strategy,OBD
η.HC > 90 %NO2/NOx < 0,5
High Efficient SCRTechnolgyη.NH3 > 94 %
Advanced DOC Technology
OptimizedNH3 Slip Catalyst
Perfect Mixing of NH3 with Exhaust Gas
SCR Catalyst Technoloy
Robust AdBlue-Injection
Excellent Decompostion of Reduction Agent
Minimum HNCO concentration
10110100 10110100
10110100 01010101
01001010 01001010
01010100 01001010
Advanced Dosing Strategy,OBD
η.HC > 90 %NO2/NOx < 0,5
Calculated NOx-Reduction and NH3 Slip as Function of NH3-Uniformity and AdBlue-Dosing Rate
NOx-Reduction
NH3-Uniformity
Alpha = 1.00
Alpha = 0.95
Alpha = 0.90
Alpha = 0.80
NH3- Slip
NH3-Uniformity
Calculated NOx-Reduction and NH3 Slip as Function of NH3-Uniformity and AdBlue-Dosing Rate
NOx-Reduction
NH3-Uniformity
Alpha = 1.00
Alpha = 0.95
Alpha = 0.90
Alpha = 0.80
In AdditionExact Adblue dosing control is needed
Influence of Dosing Frequency on the NOx Conversion Rate
NOx tailpipe +- 14%Delta_peak = 80 ppm
NOx tailpipe +- < 1%Delta_peak = 5 ppm
n = 1800 min-1
TQ = 700 NmNOxUP = 450 ppmAlpha NOx = 0,9
time [s]
0 5 10 15 20
NO
x d
ow
n S
CR
[ppm
]
260
280
300
320
340
360
380
400
High dosing frequency Low dosing frequency
Actu
al_
Dosin
g_R
ate
[m
l/h
0
400
800
Time
NO
x T
ail
pip
e
Do
sin
g R
ate
High efficiency SCR system has to have a continuous flow of Adblue At high conversion rate targets is a high dosing frequency mandatory
Agenda
• Introduction
• Challenges to Achieve High Efficient SCR
• Components of SCR System; Hardware
- Dosing System
- SCR Injector
- SCR Controller and Sensors
- SCR Catalyst System
• Limitations and Optimization of Dosing Control on SCR Efficiency
• OBD side of SCR
• Close Coupled SCR System; Practical Test Results
• Conclusion
Emitec SCR-Dosing System Gen III
In Tank SCR-Dosing system Gen III
Customized Tank for the application
Complex Emitec Gen III Dosing SystemAll in One Integration
Suction lanceTemperature sensorUrea filterLevel sensorTank heater
Heated suction line
External DCU
Installation cost:Electrical harnessFixing devicesLines connectionsQuality sensor
- Robust design based on mass production
- gasoline injector- Spray charactristic optimized
SCR Injector
Water Cooling for robustOff Road demands
GenIII – Integrated Electronics DCU
• Highly integrated electronics• Dosing injector control• Analog inputs for PT200 temperature
sensors• High current output for line heater• 32 bit microcontroller• Integrated pump and tank heater• Ultrasonic level sensor• SAE J1939 CAN bus
SCR Catalyst System and Sensors
Temp
Temp
NOx
Dosing (SW & HW)
AdBlue
LevelTemp
ECU
m_exhNOx
CAN
• Introduction
• Challenges to Achieve High Efficient SCR
• Components of SCR System; Hardware
- Dosing System
- SCR Injector
- SCR Controller and Sensors
- SCR Catalyst System
• Limitations and Optimization of Dosing Control on SCR Efficiency
• OBD side of SCR
• Close Coupled SCR System; Practical Test Results
• Conclusion
Agenda
AdBlue Decomposition with UDP + Hydrolysis Catalyst Technology
Gas T
em
pera
ture
[°C
]
150
200
250
300
350
Mass flow [kg/h]
50 250 450 650
100
150
200 300
400
600
1000
Hydrolysis catalyst supportsAdBlue Decomposition at low
temperature condition
Potential AdBlue Dosing for robust In-Pipe Dosing
Exhaust Gas Temperature during European Driving Cycle
Exhaust Gas Temperature
Start of Dosing
Theoretical AdBlue Dosing Demand based on NOx-Engine Out Emission
0
100
200
300
400
500
600
t [sec]
0 200 400 600 800 1000 1200
Adblue demand based on engine out NOx
Ad
Blu
eg
/h
0
100
200
300
400
500
600
t [sec]
0 200 400 600 800 1000 1200
Limited AdBlue Dosing based on thermal Conditionsand AdBlue Decomposition
AdBlue Dosing Limit based on Temperature���� No dosing possible
Demand can be addressedWith minor limitations
Ad
Blu
eg
/h
Increased Thermal Conditions based on EmiCat Technology
Increase Temperature using EmiCat - Technology
Start of Dosing
AdBlue Dosing Limitation and Intervall for robust Dosing!
Ad
Blu
e lim
it
0
100
200
300
400
500
600
t [sec]
0 200 400 600 800 1000 1200
AdBlue Dosing Limit basedon Temperature
Supply can behigher than Demand(Potential CO2 reduction)
Ad
Blu
eg
/h
Overall Emission Reduction based on advanced Dosing Strategy
0
100
200
300
400
500
600
t [sec]
0 200 400 600 800 1000 1200
Ad
Blu
e lim
it
0
100
200
300
400
500
600
t [sec]
0 200 400 600 800 1000 1200
NOx-Removed after Dosing Release
Ad
Blu
em
g/h
• Introduction
• Challenges to Achieve High Efficient SCR
• Components of SCR System; Hardware
- Dosing System
- SCR Injector
- SCR Controller and Sensors
- SCR Catalyst System
• Limitations and Optimization of Dosing Control on SCR Efficiency
• OBD
• Close Coupled SCR System; Practical Test Results
• Conclusion
Agenda
Overview of OBD structure
Failure handling
System OBD
Pump OBD
• MIL
• Torque limiter
• Inhibition matrix
• Failure memory
• Interface to diagnostic tester
• Specific Emission
• CAN Communication
• NOx Sensor
• Temp Sensor
• Tank level
• Electrical diagnose
• Temp / Pressure Sensor
• Motor
• Injector / Air valve
• Air in system detection
• Blocked system detection
• Interface to ECU with mask function
ECM SmartDoser
SCR System
Aftertreatment CAN BUS J1939Dosing Command
Diagnostic
Pump
Pump OBD
System OBDRegulated
Urea TankLevel
Temperature
TemperatureSensor
MAF
SensorsDrivers
Aftertreatment CAN BUS J1939Dosing Command
Diagnostic
Dosing Algorithm
Engine ParametersCatalyst Parameters
From Smart Doser to ECU
SCR Software Modules; OBD Function Smart Doser
Dosing Valve,Heater
ValvesDosing, Heater
ECM ECU Doser
SCR System
Urea TankLevel
Temperature
TemperatureSensor
MAF(Test Bench)
SensorsDrivers
Aftertreatment CAN BUS J1939Engine Working Point
Diagnostic, Full OBDEmitec Dosing
Algorithm
Catalyst Parameters Pump
Pump OBD
ValvesDosing, Heater
NOx SensorsVia CAN
System OBDRegulated System OBD
Regulated
SCR Software Modules; OBD Function ECU Doser
Emitec Technical solutions to comply with OBD Requirements
OBD Requirement Technical Solution System/ Pump
Lack of required reagent for a deNOXsystem
Level Sensor Measurement
System/ Pump(GenIII)
The quality of the required reagent being within the specifications declared by the manufacturer
Quality Sensor Measurement
Reagent consumption and dosing activityComparison of Level sensor information and average of dosing command
Emitec Technical solutions to comply with OBD Requirements
OBD Requirement Technical Solution System/ Pump
Lack of required reagent for a deNOXsystem
Level Sensor Measurement
System/ Pump(GenIII)
The quality of the required reagent being within the specifications declared by the manufacturer
Quality Sensor Measurement
Reagent consumption and dosing activityComparison of Level sensor information and average of dosing command
Failure of any SCR electrical component, any electrical failure of a component(e.g. sensors and actuators, dosing control unit) including reagent heating system
Out of range, Shorted high and Shorted low diagnostics on sensors and actuators including heater driver
Pump
Failure of the reagent dosing system (e.g. missing air supply, clogged nozzle, dosing pump failure)
Dosing system internal diagnostics
Major breakdown of the system Dosing system internal diagnostics
• Introduction
• Challenges to Achieve High Efficient SCR
• Components of SCR System; Hardware
- Dosing System
- SCR Injector
- SCR Controller and Sensors
- SCR Catalyst System
• Limitations and Optimization of Dosing Control on SCR Efficiency
• OBD
• Close Coupled SCR System; Practical Test Results
• Conclusion
Agenda
Compact SCR System for Heavy Duty and Non Road Mobile Machineries
DOCLS/PE-Metalit®
Compact SCR System for Heavy Duty and Non Road Mobile Machineries
AdBlue-Injector
DOCLS/PE-Metalit®
Compact SCR System for Heavy Duty and Non Road Mobile Machineries
AdBlue-Injector
Mixing Element /Hydrolysis CatalystDOC
LS/PE-Metalit®
Comparison of a Mixer / Hydrolysis Catalyst regarding Deposits at Low Temperature AdBlue Injection
Variant 1 withMixing Element
Variant 2 with Hydrolysis Catalyst
N= 1200 1/min; Md = 215 NmExhaust Mass: 326 kg/h; T = 230°CAdBlue-Dosage = 560 g/h, α = 0.8
Compact SCR System for Heavy Duty and Non Road Mobile Machineries
AdBlue-Injector
Mixing Element /Hydrolysis CatalystDOC
LS/PE-Metalit®
SCR- CatalystLS-Metalit®
Compact SCR System for Heavy Duty and Non Road Mobile Machineries, Demonstrator
close coupledDOC + 1. stage SCR
2.Stage SCR
High Efficient SCR Catalyst System for NRMM Applications
Engine
DOC(2,2 ltr) static mixer
SCR 1(6,5 ltr)
SCR 2(4,0 ltr)
close coupled
NOx T NOxT
NOx
1. Stage 2. Stage
0 Total velocity [m/s] 10
Flow / NH3 Distribution @ Close Coupled SCR Catalyst
UI = 0,96
Accumulated NOx Emissions at Alpha = 1 during NRTC
0 200 400 600 800 1000 1200 1400
0
100
200
300
0
5
0.0
30.0
60.0
90.0
time [s]
Acu
mu
late
d N
Ox [
g]
Acu
mu
late
d N
Ox [
g]
Acu
mu
late
d A
dB
lue [
g]
AdBlue-Mass
NOx Tailpipe
NOx after 1. Stage
NOx engine out
Accumulated NOx Emissionen after 1st and 2nd SCR Stage during NRTC Test
1. SCR Stage
2.SCR Stage
post SCR 2
94,6 %
91,1 %
0 200 400 600 800 1000 1200 1400
0
30
60
90
0
3
time [s]
Acu
mu
late
d N
Ox [
g]
Acu
mu
late
d N
Ox [
g]
Total NOx Reduction and NH3 Slip during NRTC Test
TailpipeNH3 concentration(no NH3 slip catalyst)
SCRa
94,6 %
time [s]
0 200 400 600 800 1000 1200 1400
0
30
60
90
0
100
NH
3[p
pm
]A
cu
mu
late
d N
ox [
g]
• Introduction
• Challenges to Achieve High Efficient SCR
• Components of SCR System; Hardware
- Dosing System
- SCR Injector
- SCR Controller and Sensors
- SCR Catalyst System
• Limitations and Optimization of Dosing Control on SCR Efficiency
• OBD
• Close Coupled SCR System; Practical Test Results
• Conclusion
Agenda
• Future engines have a tendancy of higher NOx raw emissions
• To achieve EU VI and Stage 4 final legislations, NOx conversions higher
than 95% are mandatory
• This means high efficient SCR systems working together with accurate
Adblue dosing control
• Low temperature AdBlue decomposition can be achieved with hydrolysis
catalyst technology
• Emitec flexible HW and SW architectures in dosing systems enable OBDs
system integration
Conclusion