Recent Developments in Diesel Engine Emission Control Technology. Diesel Emission Control Technology Is Making Significant Progress

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1 Recent Developments Diesel Enge Emission Control Technology November 2004 Manufacturers of Emission Controls Association Diesel Emission Control Technology Is Makg Significant Progress General technology approaches to hittg the regulations Widespread filter usage Japan and SCR Europe 2005 Filters provide PM control for U.S. HDE 2007 Filter technology Reliable regeneration Improved properties; ash storage/management Retrofit experience and options expandg NOx solutions SCR is near commercial NOx adsorbers are on HDD enge dynos Integrated solutions SCR/DPF are on vehicles LNT/DPF commercial sales Retrofit options available for combed PM/NOx reductions 1

2 Recent Developments PM Control Filters can substantially reduce diesel PM across the full range of particle sizes Technology is the state of optimization and cost reduction Integratg active regeneration Reduced back pressure and size Retrofit options expandg Sophisticated Enge Control Strategies Are Beg Developed to Manage Filter Regeneration Reference: Fiat FISITA May

3 Sophisticated Enge Control Strategies Are Beg Developed to Manage Filter Regeneration/Temperatures Soot loadg = p14 g/liter p g Peak filter exit 550 TS_0_ C vs. TS_11_5 TS_22_ o C w/o strategy TS_35_5 Temperatures [degc] Temperature gradients [degc/cm] Reference: SAE TS_52_5 TS_58_5 TS_66_5 TG_11_5 TG_22_5 TG_35_5 TG_52_5 TG_58_5 TG_66_5 Peak temp. gradient: C/cm vs o C/cm w/o strategy time Time [seconds] [second] Development of a strategy to avoid uncontrolled filter regeneration durg enge deceleration to an idle condition Implementation of additional regeneration control measures: Control of the amount of post jection Temperature compensation to fe tune the filter let temperature Adjustment of the mass flow Torque compensation DPF Substrate Design Optimization Includes Mimizg System Backpressure Example: Cordierite DPF Substrate Designs Pressure Drop (kpa) at 4 g/l soot Optimized Porosity Optimized Cell/Web RC 200/19 200/19 275/14 Coated Bare Porosity (%) Pore connectivity Source: 2004 SAE Commercial Vehicle Congress; Highway Diesel Panel 3

4 New Filter Cell Configurations Increase Ash Storage Capacity Reference: SAE Reference: SAE Diesel Particulate Filters (DPF) for Retrofits 150,000+ retrofits worldwide Many regions are mandatg their use Variety of technologies for a variety of applications Not universally applicable, but expanded applications and technologies developg 4

5 DPFs + 15 ppm S Diesel Fuel Demonstrate High Efficiencies After 400,000+ Miles of Service Emissions, g/mi Basele (ave.) ULSD + DPF 0.98 (ave. of 3 diff. vehicles) HC CO/10 PM NOx/100 Grocery Delivery Trucks with 12.7 L Enges Emissions Measured Usg City-Suburban Heavy Vehicle Re Reference: SAE Flow-Thru or Partial Filter Technologies Emergg for Diesel Retrofits Potential for 50-70% PM reduction (Level 2, one technology already verified) Can be catalyzed or used with a DOC May have applicability on older enges Filterg achieved with stered metal sheets or wire meshes Resistant to pluggg 5

6 EGR, DOC+Flow-Thru Filter Selected for Heavy-Duty Euro 4 Diesel Application DOC Filter 5 DOC/Filter Elements Exhaust Inlet Source: MAN Euro 4 Application with Flow-Thru Filter Demonstrates 60-70% PM Reduction PM Emissions, g/kw-hr Euro 4/5 Limit Euro 4/5 Limit Enge- Tailpipe ETC ESC Source: MAN 6

7 Active DPF Types Available for Low Temperature Exhaust Applications Passive DPFs with Electric Assist Uses on-board heaters termittently combation with catalyst-based filters or fuel borne catalysts Electrically-Heated Active DPFs Regenerated on-board at stand-still or off-board / exchange Fuel Burner / Thermal Regeneration Air Management with Active Air Intake Throttlg to Raise Exhaust Gas Temperature Diesel Fuel Injection with a DOC or Catalyst-Based DPF Examples of Active DPF Technology Options Catalyst-Based Filter with Electric Heater Assist Uncatalyzed Filter with Fuel Burner Muffler Uncatalyzed Filter Combustion Chamber Controller 7

8 Fuel Injection Active Filter Regeneration System Diesel fuel provides regeneration heat source Preferred regeneration characteristics Faster, more uniform heat up of DPF Quick and efficient regenerations Uniform temperature distribution DPF Compatible with NOx Systems Dedicated controller with diagnostic functions Fuel Injection Unit DPF DOC Heat Exhaust gas Diesel vapor Recent Developments NOx Reduction Technologies Technology development cludes: NOx Adsorbers Contued progress on performance/durability Utilizg reformate for enhanced regeneration/desulfation Selective Catalytic Reduction Ready for commercial troductions 8

9 Adsorber Performance Wdow Stable after Multiple Sulfation and Desulfation Cycles Cycle NOx Performance of Low Temp LNT Low Temperature system has excellent activity wdow at low SV NOx efficiency mataed through end-oflife simulation NOx Conv (%) s L/ 3s R (0.27 g NO2/L flux/m) after 20 DeSOx after 55 DeSOx 35K VHSV Inlet Temperature ( C) Reference: AVECC 2004 Hydrogen/CO Reformate Significantly Improves LNT Regen. & Desulfation Performance Plasma reformer uses 250W to form 9% H 2 and 14% CO from 35 kw of fuel; w/ DOC: 20% H 2 Catalytic reformer operates as low as 200 C to produce pulsed CO/H 2 reformate Reference: SAE Reference: DEER 2004 CO/H2 also shown to significantly lower LNT desulfation temperatures (up to 100 C) 9

10 NO 2 /NO Ratio Is Important Achievg Good Low Temperature SCR Performance fast slow Reference: SAE SCR Applications for 2005 Euro 4 Heavy-Duty Standards: High Performance & Durability NOx Emissions, g/kw-hr Enge- SCR -Fresh SCR h aged Agg done usg 550 C max. temperature, high oil consumption 82% eff. 81% eff. 76% eff. 85% eff. Reference: SAE SCR h aged 8.5 liter SCR catalyst evaluated on a 10 liter enge; Agg estimated to be equivalent of 1.2 million km DOC h aged SCR 10

11 Integrated Systems HDD DPF/LNT Demonstrates 90% NOx Efficiency after 2000 Hours of Agg NOx (g/bhp-hr) 15 liter 475 hp 2004 Cumms enge. SVR DPF = 3.5; SVR LNT = 2.9 FTP Composite NOx Enge- Level Age (hours) NOx Mean Desulfation 23 desulfations at 675 C and λ<0.9 for mutes; 4.5% cycle average fuel penalty; 15 ppm sulfur fuel (Reference: DEER 2004) 11

12 Catalyst Integration for NOx Adsorbers and Filters Is Commercial Toyota DPNR System NOx adsorber catalyst is coated directly on wall-flow filter Active oxygen aids filter regeneration First commercial applications: - Euro passenger car (2.0L): 0.12 g/km NOx (50% of Euro IV); g/km PM - Japanese light-duty truck enge (4.0L) References: SAE and Prototype V6 Diesel Demonstrates Full Useful Life B 5 NOx Performance with DPF/LNT System g/mi NOx demonstrated after 68 desox cycles (equiv. to 150K miles) 4.2 Liter V6, 5000 lb. ETW Source: Cumms 2004 DEER 12

13 Integrated Solutions for Combed PM/NOx Reductions Available for Retrofit Lean NOx Cat. + DPF or DOC 25-35% NOx reduction Low Pressure EGR + DPF 40-60% NOx reduction Emulsified Diesel Fuel + DOC or DPF 15-40% NOx reduction Verified Retrofit SCR Systems Expected In the Near Future Other Recent Diesel Technology Items the News Volvo launches bus fleet Sweden equipped with DPF/SCR systems; claimed to be cleanest diesel buses operatg on the planet (below Euro V heavy-duty limits) Univ. of Wiscons ws DOE FutureTruck competition for third straight year with diesel hybrid Explorer equipped with DPF/SCR system (near SULEV NOx levels) GTL test program with Class 6 delivery trucks California shows significant NOx and PM emission benefits for GTL vs. CARB diesel (SAE Paper No ) 16% lower NOx, 23% lower PM over the NYC Bus cycle With CB-DPF: 20% lower NOx, 97% lower PM First vehicle results for PM sensor with transient response presented at DEER 2004 DPF-equipped passenger cars Europe approach one million sce 2000 PSA troduction with good performance (systems clude use of fuel borne catalyst or catalyzed filter) 13

14 Conclusions All Major Markets Movg to Tight PM and NOx Emission Standards for Diesel Enges A Variety of Technologies Are Available and Emergg for PM, NOx, and Toxic HC Emission Control for Both Diesel Light-Duty and Heavy-Duty Vehicles Retrofit Experience Is Growg Worldwide with a Variety of Technology Options Available for Controllg PM and NOx Emissions from On- and Off-Road Diesel Enges Technologies Are Advancg and Recent Developments Indicate that HDDE 2007/2010 and Tier 2/LEV 2 Emission Levels Will Be Achievable On-Road Diesel Technologies Will Migrate to Nonroad Diesel Applications The Ultimate Solution to Reducg Emissions from Diesel Enges Requires a Systems Approach Utilizg Advanced Enge Designs, Advanced Integrated Emission Control Technology, and Low Sulfur Diesel Fuel 14