1
Fuel-Borne Catalysts for Diesel Particulate Filter Regeneration
Dr. Thierry SEGUELONGRHODIA Electronics & Catalysis
February 01, 2001
Outline.
• Introduction.• Principle of Operation.• Filtration Efficiency.• Selection in Fuel-borne Catalysts.• Strategy for Regeneration.• Serial and Commercial Applications.• Conclusions.
2
0.0 0.2 0.4 0.6 0.8 1.00.00
0.02
0.04
0.06
0.08
0.10
EURO 4
EURO 3
Type Approval Data acc. KBA, Flensburg
Model Year 1997 Model Year 1998 Model Year 2000
HC + NOx [g/km]
Parti
cula
tes
[g/k
m]
VW Lupo TDI 1.2L “3 Liter Vehicle“ (Inertia Weight 910 kg)
Audi A2 TDI 1.2L(Inertia Weight 910 kg)
PSA 607 2.2L with DPF System(Inertia weight 1590 kg)
Data from Diesel Passenger Cars on the NEDC.
Courtesy of FEV Aachen
Outline.
• Introduction.• Principle of Operation.• Filtration Efficiency.• Selection in Fuel-borne Catalysts.• Strategy for Regeneration.• Serial and Commercial Applications.• Conclusions.
3
Principle of Operation of Fuel-Borne Catalyst Technology.
l Continuous and fresh catalyst supplying.
l Best 3D-Catalyst dispersion (highest contact point numbers).
l To favour propagation of soot combustion process to the entire soot layer (complete regeneration).
oxide catalystand soot aggregate
Courtesy of Renault S.A.
Regeneration Cycleof Diesel Particulate Filter.
4
Outline.
• Introduction.• Principle of Operation.• Filtration Efficiency.• Selection in Fuel-borne Catalysts.• Strategy for Regeneration.• Serial and Commercial Applications.• Conclusions.
Trap efficiency (VERT program).
1,0E+0
1,0E+1
1,0E+2
1,0E+3
1,0E+4
1,0E+5
1,0E+6
1,0E+7
10 100 1000diameter [nm]
conc
entr
atio
n dW
[cm
-3]
without particle trap
air
DPX9 standard. fuel
DPX9
with particulate trap
1,0E+0
1,0E+1
1,0E+2
1,0E+3
1,0E+4
1,0E+5
1,0E+6
1,0E+7
10 100 1000diameter [nm]
conc
entr
atio
n dW
[cm
-3]
without particle trap
air
Fuel + DPX9
standard fuel
Liebherr D 914T engine (6.11 l – 4 cylinders – DI – Turbocharger - EURO 0)CORNING EX80 Cordierite / 25ppm of cerium (EOLYS™).
1400 min-1 / 297 Nm 2000 min-1 / full load
Courtesy of Corning
Efficiency > 99.9%
5
Outline.
• Introduction.• Principle of Operation.• Filtration Efficiency.• Selection in Fuel-borne Catalysts.• Strategy for Regeneration.• Serial and Commercial Applications.• Conclusions.
Criteria for Fuel-Borne CatalystsSelection.
l Health and environmental innocuousness (such as EINECS or ELINCS Notifications in European Area),
l and its use in combination with Diesel Particulate Filters (Swiss BUWAL, German UBA, French and Austrian authorities).
l In European Area, only EOLYS™ (Cerium-based) and SATACEN™ (Iron-based) Fuel-Borne Catalysts have been approved by Swiss BUWAL and European Union authorities (included German UBA).
l Compatibility with filter materials and vehicle parts (fuel injection system, engine parts, fuel tank materials, on-board dosing system, oxidation catalyst…).
l Compatibility and solubility in common diesel fuels.l Temperature and time stability.
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Practical Requirements for Serial Applications
l Automatic On-Board Dosing System for Fuel-Borne Catalyst (recently mandatory by Swiss BUWAL authority for Off-Road Applications).
l Diesel Particulate Filter :§ Efficiency§ Durability§ Integration in exhaust pipe line§ Robust (highest soot loading limits).
l On-Board Diagnosis System :§ Detection of DPF cracking,§ Stop the Fuel-Borne Catalyst addition.
Automatic On-Board Dosing System.
Diesel Fuel
Fuel-BorneCatalyst
Feeding pump
Engine injection pump
Controllamp
Power
Fuelreturn ligne
Fuel feeding line
E.C.U.
IC Engine
Fuel level sensor
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Diesel Particulate Filter Materials.
On-Board Diagnosis Systemvia Back-Pressure Sensor.
0
50
100
150
200
250
200 300 400 500 600 700 800 900 1000 1100 1200
Air Mass Flow (kg/h)
Bac
k-p
ress
ure
(m
bar
)
DPF empty
DPF damaged
Warning !!!
Regeneration to be started
DPF full
Courtesy of Zeuna Stärker
8
Outline.
• Introduction.• Principle of Operation.• Filtration Efficiency.• Selection in Fuel-borne Catalysts.• Strategy for Regeneration.• Serial and Commercial Applications.• Conclusions.
Impact of Fuel-Borne Catalyst.
Engine operating map where domains are outside continuous regeneration area.
Lo
ad
RPMIdle
Continuousregeneration
Conditions whereregeneration must be initiated
300°C
400°C
With Fuel-Borne Catalyst
unpredictable spontaneous regeneration
RPM
Lo
ad
Idle
No regeneration possible
Without Fuel-Borne Catalyst
Natural regeneration
600°C
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Temporary Heat Injection Strategy.
external supply
electrical heater,catalytic oxidation reaction,fuel burner,etc…
engine tuning& management
intake air throttling,turbo by-pass,increased EGR rate,pilot injection,post-injectionmulti-injectionetc…
AND/OR
For durable and reliable trap regenerations, strategies in after-treatment technologies need a global system
approach and engine management.
ns
without PI
Optimization of Strategy.Accumulation zone Regeneration zone Safety zone
CriticalSoot Loading
Optimum forStarting regeneration
Fuel penalty evolutionwith regeneration
Overall in Fuel Penalty
Trap loading
Su
pp
lem
ent.
Fu
el c
on
sum
pti
on
(qu
alit
ativ
) su
Fuel penalty caused by back-pressure increase
10
Outline.
• Introduction.• Principle of Operation.• Filtration Efficiency.• Selection in Fuel-borne Catalysts.• Strategy for Regeneration.• Serial and Commercial Applications.• Conclusions.
PSA Peugeot-Citroën Group.
l First Serial Application on Peugeot 607 model (HDI 2.2 l).
l Common Rail Injection System.l In 2000 year, around 8’000
vehicles have been sold on French market.
l In 2001, forecast of more than 35’000 Peugeot 607 model in European market.
l Large extension of the technology to other PSA’s HDI vehicles.
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Principle of PSA’s Filter Regeneration.
Cerium-based Fuel-Borne
Catalyst
SiC-Diesel Particulate Filter
Oxidation Catalyst
Strategy for Complete Regeneration.
0
150
300
450
600
Exhaust Temperature Soot combustion
Tem
pera
ture
(°C
)
Ceria-Catalyst Effect
Natural Soot Combustion
Exhaust Temperature
Post-injection
HydrocarbonsOxidation
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Cerium-dosing systemECU
Electrical PumpLevel sensor
Diesel-Fuel levelInjectionModule
Diesel Tank
Engine Information dashboard
Additive levelECU
Diagnosis Information
Fuel level
Peugeot 607 HDI :Automatic On-Board Dosing System
Courtesy of Marwall Systems
Peugeot 607 HDI : Exhaust Canning.
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1
10
100
1000
1 10 100 1000
Particulate matter emission (1/cm3)
Median diameter (nm)
Air dilution
HDi + Oxi cat+
SiC DPF
2L HDi - 40632 kph - 2nd gear 1
10
100
1000
1 10 100 1000
Particulate matter emission (1/cm3)
Air dilution
HDi + Oxi cat+
SiC DPF
2L HDi - 40670 kph - 5th gear Median diameter (nm)
COMPARISON OF SiC FILTER PARTICULATE MATTER EMISSIONWITH AIR DILUTION ON A 406 - 2L HDi
Courtesy of PSA Group
PM Emissionsmeasurement limit
0
0,001
0,002
0,003
0,004
0,005
0,006
0,007
MINI MAXI
g/k
m
sample = 10 vehiclesmileaging < 5000 kmdiesel fuel 320 ppm S
EMISSIONS RESULTS ON MVEG DRIVING CYCLEWITHOUT REGENERATION
Courtesy of PSA Group
14
40
12
20
41 to 4 2 to 3
2 to 3
0
10
20
30
40
50
HDi HDi with DPF classical gasolineengine
Mitsubishi GDi Blank test
mg/km
maximum valueminimum value
EURO 3
EURO 4
PARTICULATE MATTER EMISSIONPARTICULATE MATTER EMISSIONECE + EUDCECE + EUDC
Courtesy of PSA Group
RENAULT’s Strategy for Year 2002/2003.
Courtesy of Renault S.A.
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Delayed Pilot and Main Injection.
Courtesy of Renault S.A.
Outline.
• Introduction.• Principle of Operation.• Filtration Efficiency.• Selection in Fuel-borne Catalysts.• Strategy for Regeneration.• Serial and Commercial Applications.• Conclusions.
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Conclusions (I).
l Fuel-Borne Catalyst technology can make soot combustion easier and safely for DPF regeneration, with continuous, fresh and 3D Catalyst supplying in the accumulated soot in the trap.
l Fuel-Borne Catalysts have been developing to fulfil specifications of final requirements, such as health and environmental authorities and complete vehicle integration.
l « DPF + Fuel-Borne Catalyst » technology is efficient in diesel particulate matter emissions reduction (loading and regeneration steps), without secondary emissions.
Conclusions (II).l The use of Fuel-Borne Catalyst in association with
DPF has been recommended by Swiss BUWAL and German UBA authorities.
l Only EOLYS™ (Cerium-based) and SATACEN™(Iron-based) Fuel-Borne Catalysts have been approved in European Area for both On-Road and Off-Road Applications.
l The use of Fuel-Borne Catalyst requires Automatic On-Board Dosing System for FBC addition (recently mandatory by Swiss Buwal) and On-Board Diagnosis System for DPF crack detection and stop of FBC addition.
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Conclusions (III).
l In case of unpredictable driving cycle operation and/or continuous low exhaust gas temperature (a typical feature in serial applications), engine management systems and heat injection must be applied to get reliable and durable regeneration of DPF and must be optimised for diesel fuel consumption saving.
l Developments in diesel fuel injection technologies, internal combustion chamber, diesel fuel quality, new filter design and integrated system approaches… will improve the economical and technical aspects for durable and reliable DPF regeneration.
The author thanks :
l Corning.
l FEV Aachen.
l PSA Peugeot-Citroën.
l Renault S.A.
l TTM Zurich
l Zeuna Stärker
for making available the detailed results, graphs and pictures.
Acknowledgements.