Fuel-Borne Catalysts for Diesel Particulate Filter Regeneration
Dr. Thierry SEGUELONG RHODIA 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.
1 Data from Diesel Passenger Cars on the NEDC.
0.10 Type Approval Data acc. KBA, Flensburg Model Year 1997 0.08 Model Year 1998 Model Year 2000
0.06 Particulates [g/km] EURO 3
0.04 VW Lupo TDI 1.2L “3 Liter Vehicle“ (Inertia Weight 910 kg) EURO 4
Audi A2 TDI 1.2L 0.02 (Inertia Weight 910 kg)
PSA 607 2.2L with DPF System (Inertia weight 1590 kg) 0.00 0.0 0.2 0.4 0.6 0.8 1.0 HC + NOx [g/km] Courtesy of FEV Aachen
Outline.
• Introduction. • Principle of Operation. • Filtration Efficiency. • Selection in Fuel-borne Catalysts. • Strategy for Regeneration. • Serial and Commercial Applications. • Conclusions.
2 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 catalyst and soot aggregate
Regeneration Cycle of Diesel Particulate Filter.
Courtesy of Renault S.A.
3 Outline.
• Introduction. • Principle of Operation. • Filtration Efficiency. • Selection in Fuel-borne Catalysts. • Strategy for Regeneration. • Serial and Commercial Applications. • Conclusions.
Trap efficiency (VERT program).
Liebherr D 914T engine (6.11 l – 4 cylinders – DI – Turbocharger - EURO 0) CORNING EX80 Cordierite / 25ppm of cerium (EOLYS™).
1,0E+7 1,0E+7
1,0E+6 1,0E+6 DPX9 standard. fuel without Fuel + standard fuel particle trap DPX9 1,0E+5 without 1,0E+5 particle trap
1,0E+4 1,0E+4
1,0E+3 1,0E+3 air with particulate trap 1,0E+2 1,0E+2 concentration dW [cm-3] concentration dW [cm-3] DPX9 air 1,0E+1 1,0E+1
1,0E+0 1,0E+0 10 100 1000 10 100 1000 diameter [nm] diameter [nm] 1400 min-1 / 297 Nm 2000 min-1 / full load Efficiency > 99.9% Courtesy of Corning
4 Outline.
• Introduction. • Principle of Operation. • Filtration Efficiency. • Selection in Fuel-borne Catalysts. • Strategy for Regeneration. • Serial and Commercial Applications. • Conclusions.
Criteria for Fuel-Borne Catalysts Selection. 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.
5 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.
Control lamp
Power Feeding E.C.U. pump Fuel-Borne Catalyst Engine injection pump
Fuel return ligne Fuel level sensor
IC Engine
Fuel feeding line
Diesel Fuel
6 Diesel Particulate Filter Materials.
On-Board Diagnosis System via Back-Pressure Sensor.
250 Warning !!!
200
DPF full 150 Regeneration to be started pressure (mbar) 100 DPF empty - Back 50
DPF damaged 0 200 300 400 500 600 700 800 900 1000 1100 1200
Air Mass Flow (kg/h) Courtesy of Zeuna Stärker
7 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.
Without Fuel-Borne Catalyst With Fuel-Borne Catalyst
Natural Continuous regeneration regeneration 600°C 400°C unpredictable
Load spontaneous Load No regeneration possible regeneration 300°C Conditions where regeneration must be initiated
Idle RPM Idle RPM
8 Temporary Heat Injection Strategy.
intake air throttling, turbo by-pass, engine tuning increased EGR rate, pilot injection, & management post-injection multi-injection etc… AND/OR
electrical heater, external supply catalytic oxidation reaction, fuel burner, etc…
For durable and reliable trap regenerations, strategies in after-treatment technologies need a global system approach and engine management.
Optimization of Strategy.
Accumulation zone Regeneration zone Safety zone
Overall in Fuel Penalty su ) Optimum for Starting regeneration ns qualitativ ( Fuel penalty evolution Critical with regeneration Soot Loading Fuel penalty caused by
Supplement. Fuel consumption back-pressure increasewithout PI
Trap loading
9 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.
10 Principle of PSA’s Filter Regeneration.
Cerium-based Oxidation Catalyst Fuel-Borne Catalyst
SiC-Diesel Particulate Filter
Strategy for Complete Regeneration.
Natural Soot Combustion 600 Ceria-Catalyst (°C) 450 Effect Hydrocarbons Oxidation 300 Post-injection 150 Temperature Exhaust Temperature 0 Exhaust Temperature Soot combustion
11 Peugeot 607 HDI : Automatic On-Board Dosing System
Engine Information dashboard Fuel level ý ECU Additive level íDiagnosis Information
Cerium-dosing system ECU
Diesel Tank
Injection Electrical Pump Module Diesel-Fuel level Level sensor
Courtesy of Marwall Systems
Peugeot 607 HDI : Exhaust Canning.
12 COMPARISON OF SiC FILTER PARTICULATE MATTER EMISSION WITH AIR DILUTION ON A 406 - 2L HDi
Particulate matter emission (1/cm3) Particulate matter emission (1/cm3) 1000 1000
Air dilution Air dilution
100 100
HDi + Oxi cat HDi + Oxi cat + + SiC DPF SiC DPF 10 10
2L HDi - 406 2L HDi - 406 th 32 kph - 2nd gear 70 kph - 5 gear 1 Median diameter (nm) 1 Median diameter (nm) 1 10 100 1000 1 10 100 1000 Courtesy of PSA Group
EMISSIONS RESULTS ON MVEG DRIVING CYCLE WITHOUT REGENERATION sample = 10 vehicles mileaging < 5000 km PM Emissions measurement limit diesel fuel 320 ppm S 0,007
0,006
0,005
0,004
g/km 0,003
0,002
0,001
0 MINI MAXI
Courtesy of PSA Group
13 PARTICULATE MATTER EMISSION ECE + EUDC
mg/km
50 EURO 3
40 maximum value 40 minimum value
30
EURO 4 20 20
12
10
1 to 4 4 2 to 3 2 to 3
0 HDi HDi with DPF classical gasoline Mitsubishi GDi Blank test engine Courtesy of PSA Group
RENAULT’s Strategy for Year 2002/2003.
Courtesy of Renault S.A.
14 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.
15 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.
16 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.
Acknowledgements.
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.
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