Expediting the Use of Clean-Diesel Expediting the Use of Clean-Diesel Engines with Retrofit Emission Control Engines with Retrofit Emission Control

Technologies Technologies

Air Quality Conference for Local Elected Air Quality Conference for Local Elected OfficialsOfficials

May 10-11, 2001May 10-11, 2001Sacramento, CASacramento, CA

Presentation OutlinePresentation Outline

Introduction

Background

Retrofit Control Technologies

Elements of a Retrofit Program

Cost Estimates

Conclusion

IntroductionIntroduction

Diesel Engines Are a Major Source of NOx, PM, and Toxic Emissions

Even with the Prospect of Tighter Emission Standards in the Future, Existing, High-Emitting Diesel Engines Will Be in Use for the Next 10 to 20 Years

Retrofitting Existing Diesel Engines with Exhaust Control Technologies or Converting Diesel Engines to Natural Gas Are Available Strategies to Reduce Emissions and Expedite Clean-Vehicle Deployment

A Successful Retrofit Program Must Be Properly Designed and Implemented

Available Retrofit TechnologiesAvailable Retrofit Technologies

PM, CO, HC and Toxics

– Diesel Oxidation Catalysts (DOC)

– Diesel Particulate Filters (DPF)

– Enhanced Combustion Modifications (e.g., cams, coatings, superchargers)

– Crankcase Emission Controls

Available Retrofit Technologies (cont.)Available Retrofit Technologies (cont.)

NOx

– Selective Catalytic Reduction

– Lean NOx Catalyst Technology

– Systems Strategies (e.g., engine modifications to reduce NOx plus PM exhaust controls)

– EGR

Retrofit ExperienceRetrofit Experience

Mining

Materials Handling

Truck and Bus

Marine Vessels and Locomotives

Stationary Diesel Engines

Overview of Retrofit ProgramsOverview of Retrofit Programs

The Number and Scope of Retrofit Programs Is Rapidly Growing

– North America (California, New York, New England, Mexico, and elsewhere)

– Europe (Austria, Finland, France, Germany, Sweden, Switzerland, and United Kingdom)

– Asia (Hong Kong, Korea, Japan, and Taiwan)

– Latin America (El Salvador and Nicaragua)

Diesel Oxidation CatalystsDiesel Oxidation Catalysts

Carbon

SOF

NOx

CO

HC

Carbon

NOx

Water

Oxidation Catalysts Oxidize CO, HC, and SOF to Reduce PM, CO, HC, and Toxic Emissions.

Diesel Oxidation Catalysts Are Efficient and Diesel Oxidation Catalysts Are Efficient and ProvenProven

Oxidation Catalyst Control Capabilities– PM -- 20-50% Reduction

– CO and HC -- >90%

– Toxic HCs -- >70%

DOCs Destroy Large Fractions of Toxic EmissionsDOCs Destroy Large Fractions of Toxic Emissions

1.290.8

1.86

9.41

11.36

0.560.10.2

2.8

6.8

0

2

4

6

8

10

12

Formal

dehyd

e

Aceta

ldeh

yde

Acrolie

n

1,3

Butadie

ne

PAHs

Before After

Toxic Hydrocarbon Compounds Reduced by 68%

PAH Emissions Reduced by 56%

Greater Reductions Possible with Low Sulfur Fuel

mg/bhp-hr

Source: MECA 1999

Diesel Particulate FiltersDiesel Particulate Filters

Trapped PMCell Plugs

Exhaust(PM, CO, HC)Enter

Ceramic HoneycombWall

Exhaust (CO2, H2O)Out

Diesel Particulate Filters Are Efficient and Diesel Particulate Filters Are Efficient and Are Developing an Impressive Track RecordAre Developing an Impressive Track Record

Filter Control Capabilities– PM -- 80%->90% Reduction

– CO and HC -- >90%

– Toxic HCs -- >90% Reduction

ARB/ARCO/CEC Retrofit Demonstration ARB/ARCO/CEC Retrofit Demonstration Program Program

0

0.5

1

1.5

2

2.5

CO NOx/10 HC PM

Control (CARB)

Test (CARB)

Test (EC-D)

Test (EC-D, filter)

Source: SAE 2000-01-1854

undetectable

Filters Destroy Large Fractions of Toxic EmissionsFilters Destroy Large Fractions of Toxic Emissions

0

0.2

0.4

0.6

0.8

1

1.2

1.4

Before After

PAH Emissions Reduced by 89%

PAH, mg/bhp-hr

Source: MECA 1999

1.2

0.14

Recent Data Reports nitro-PAH Are Decreased with Recent Data Reports nitro-PAH Are Decreased with FiltersFilters

Octel, SAE TopTec 9/00

Filters Are Very Effective in Reducing Ultra-Fine Filters Are Very Effective in Reducing Ultra-Fine ParticlesParticles

Post filtered gas has the same particulate concentrations as the dilution air

Carbon-Based Ultra-Fine Particles Reduced by in Excess of 99.99 %

Peugeot SAE 2000-01-0473

Diesel Particulate Filter Retrofit DurabilityDiesel Particulate Filter Retrofit Durability

VehicleApplication

Engine Displacement (l) and Power (hp)

Accumulated Distance (mi)

PM Reduction Efficiency (%)

Euro ESC1 US FTP2

Intercity Train 14 430 372,902 89 99

Airport Bus 10 292 357,531 80 n.a.

Express Bus 10 368 304,598 94 94

Mail truck 7 236 294,469 78 93

City Bus 11 260 142,205 93 98

Refuse Truck 7 235 128,342 93 n.a.

Refuse Truck 7 235 65,743 92 n.a.

Averages: 194,456 88 96

SCR

SCR ApplicationsSCR Applications

SCR Has Been Used Successfully on Stationary SCR Has Been Used Successfully on Stationary Sources and Is Now Used for Mobile SourcesSources and Is Now Used for Mobile Sources

SCR Control Capabilities– PM – 30-50% Reduction

– CO and HC -- >80%

– Toxic HCs – >80%

– NOx – 60 - >80%

SCR Test Results in European & US Steady State Test SCR Test Results in European & US Steady State Test CycleCycle

0

500

1000

1500

2000

2500

1 2 3 4 5 6 7 8 9 10 11 12 13mode

NO

x [g

/h]

NOx before catalyst: 6.79 g/bhphr NOx after catalyst: 1.34 g/bhphr

NOx conversion: 80%

Integrated System Using a DOC, DPF, and SCRIntegrated System Using a DOC, DPF, and SCR

Engine

Catalyst/Filter SCR Oxidation Cat

Removal of HC, CO, PM

Removal of NOx

Removal of NH3 slip if required

4-way conversion

Urea

Integrated System – Lean NOx Catalysis + Integrated System – Lean NOx Catalysis + FilterFilter

Integrate heat transfer and chemistry Integrate heat transfer and chemistry for simultaneous reduction of for simultaneous reduction of NOx, CO, HC, & PMNOx, CO, HC, & PM

LNCLNC(NOx reduction)(NOx reduction)

DPFDPF(CO, HC, and(CO, HC, andPM oxidation)PM oxidation)

DirtyDirtyExhaustExhaust

InIn

Clean AirClean AirOutOut

GainGainHeatHeat

LoseLoseHeatHeat

RecuperatorRecuperator

SupplementaSupplementary HC ry HC

InjectionInjection

Elements of a Proper Retrofit Control ProgramElements of a Proper Retrofit Control Program

The Condition of the Engine Is an Important Factor in Making a Decision Whether to Retrofit Control Technology

For Filter Retrofit, Vehicle Application, Exhaust Temperature (Duty Cycle), and Fuel Sulfur Level Must Be Properly Matched

Elements of a Proper Retrofit Control Program (cont.)Elements of a Proper Retrofit Control Program (cont.)

Retrofit Technology Check List

– Size

• Properly Sized Control Technologies Ensure Low Back Pressure and Maximum Performance

– Vehicle Integration

• An Important Aspect of Control Technology Retrofit, but Has Been Successfully Accomplished on Both On- and Off-Road Vehicles (muffler replacement or in-line installation)

Elements of a Proper Retrofit Control Program (cont.)Elements of a Proper Retrofit Control Program (cont.)

Retrofit Technology Check List (cont.)

– Fuel Quality

• For PM Control, <15 ppm Allows for Maximum Emission Control Performance and Best Filter Regeneration Characteristics

• Oxidation Catalysts Can Be Formulated to Minimize Sulfation, but at the Expense of Some Reduced Emission Control Performance

• Some Technologies Can Be Applied to Certain Applications Using Fuels with Higher Sulfur Levels

– Maintenance

• Vehicles to Be Retrofitted Should Be Properly and Regularly Maintained

• Retrofit Technology Should Be Maintained per Manufacturer’s Recommended Procedures

Filter System Retrofitted to a BusFilter System Retrofitted to a Bus

Filter System Retrofitted to a BusFilter System Retrofitted to a Bus

Filter System

Filter System Retrofitted to a Refuse TruckFilter System Retrofitted to a Refuse Truck

Filter System

Direct Fit In-line ConverterDirect Fit In-line Converter

Catalyst

Integrated Converter MufflerIntegrated Converter Muffler

Muffler Replacement

Central Artery/Tunnel Project (Big Dig)Central Artery/Tunnel Project (Big Dig)

Filter System

Current Cost Current Cost

Filter Technology

– Depends on Engine Size – Approximately $3000 - $5500 per Vehicle Depending on Type of Vehicle Integration

– 2-4 Hours for Installation

– Ash Removal at ~60,000 Miles

Oxidation Catalyst Technology

– Approximately $500 - $1800 per Vehicle Depending on Type of Vehicle Integration

– 2 Hours for Installation

– Maintenance – Periodic Inspection and Cleaning if Necessary

Current Cost (cont.)Current Cost (cont.)

SCR

– Approximately $15,000 - $50,000 per Vehicle Depending on Type of Vehicle

– 2 Days for Installation

– Reagent Consumed at 6% of Fuel Consumption (depending on conversion efficiency, engine type, etc.)

Lean-NOx/Filter Technology

– $5,000 - $10,000 per Vehicle Depending on Type of Vehicle

Costs for Retrofit Control Technologies Will Decrease as Sales Volumes Increase and Systems Are Fully Optimized

Stationary Engine Urea SCR Cost Effectiveness Stationary Engine Urea SCR Cost Effectiveness (2000 hp Diesel Engine)(2000 hp Diesel Engine)

400 hrs/yr 8000 hrs/yr

NOx removed 11.3 TPY 225 TPY

Reagent usage 22.6 TPY 450 TPY

Capital recovery factor .20 .26

Reagent, $/ton $ 400 $ 200

Annual cost: Capital 17,800 24,960

Reagent 9,040 90,000

Total $26,840 $115,160

Cost/ton NOx removed $ 2,375 $ 512

ConclusionsConclusions

A Variety of Demonstrated Retrofit Technologies Are Available to Significantly Reduce PM, NOx, HC, CO, Toxic, Smoke, and Odor Emissions from Existing HDDEs

A Growing Number of Retrofit Programs Are Being Successfully Implemented

A Properly Designed and Implemented Program Can Achieve Important Diesel Exhaust Emission Reductions and Expedite the Use Of Clean-Diesel Engines

Active Participation by All Interested Parties Will Be A Key Element in a Successful Program