New Jersey Clean Air Council HearingApril 13, 2011

Emissions and Exposure Reduction Through the Use of New Technology

Diesel Engines

Joe SucheckiEngine Manufacturers Association

Overview• Provide Some Comments on Cumulative Impacts of Air

Pollutants• Discuss Issues Associated with Diesel Emissions• Provide the Latest Information on the Significant Emissions

Reductions from Diesels(Clean Air Council Issue 7)

Cumulative Impacts of Multiple Air Pollutants• Researchers and regulators are just beginning to address

cumulative impacts of pollutants• EPA and the Health Effects Institute have new programs on

multi-pollutant analysis• Epidemiology studies of air pollution capture the effects of

multipollutants in the ambient air– Health effects studies include exposure to mixtures– Researchers then try to apportion measured health effects from

individual pollutants– Question is which pollutants may be responsible

• Difficult, expensive and necessary question to answer for New Jersey?

Diesel Emissions in a Multiple Pollutant World• Diesel Emissions are a mixture of many air pollutants• Diesel is a source, not a unique pollutant• Diesel emissions cannot be distinguished in the atmosphere• There is no unique maker for Diesel PM• There will always be diesel exhaust, but the composition of

the exhaust can be changed• There is no evidence to indicate that diesel PM is any more

or less harmful than PM from other sources• Ambient diesel PM levels have decreased significantly over

the last decade

Diesel Emissions and Multiple Pollutant Exposure• Diesel emissions contribute to ambient air pollution• Contribution varies widely and is dependent on source

apportionment method used.• Industry and regulatory approach is to reduce diesel source

emissions.• Result is near-zero emissions from New technology Diesel

Engines.

0.010.01 0.100.10

0.20.2

1.21.2

2.52.5

4.04.0

5.05.0

0.00.0

NO

xN

Ox

[g/B

HP-

hr]

[g/B

HP-

hr]

PMPM [g/BHP-hr][g/BHP-hr]

1994

0.00.0

1998

2002

Evolution of US Heavy Duty Diesel On-Road Emission Standards

2007 (NTDE)

2010 (NTDE)

ULSDULSD15 PPM15 PPM(10/06)

500 PPM500 PPM(10/93)

FUELFUELSULFURSULFUR

Fuel Sulfur

Traditional Diesel Exhaust (TDE)

Exhaust from engines utilizing old technologies :– Pre-1988 diesel engines sold and in use prior to the US

EPA diesel particulate standards– “Transitional“ 1988-2006 diesel engines

• Progressive improvements in engine design, but• Prior to the full-scale implementation of multi-component

after-treatment systems

TDE Government Agency Hazard Assessments

• Based on the large toxicological database of TDE from pre-1988 engines

• All earlier epidemiology and most laboratory toxicology studies used TDE

• Concluded that high levels of DE are likely to increase cancer and non-cancer health effects

• In 1989, International Agency for Research on Cancer classified DE as a "probable" human carcinogen

• In 1998, particulate emissions from diesel-fueled engines listed as a "toxic air contaminant" (TAC) by California EPA

• In 2000, US EPA classified diesel exhaust as a "mobile source air toxic"

• In 2002, US EPA classified pre-1995 diesel exhaust as "likely to be carcinogenic to humans“

New Technology Diesel Exhaust (NTDE)

Exhaust from engines utilizing new technologies:

– Meets EPA & CARB 2007 PM and NOx standards– Fully integrated electronic control systems– Ultra low sulfur diesel fuel (< 15 ppm)– Oxidation catalysts– Wall-flow diesel particulate filters (DPFs)– Applies to both new and retrofitted engines

Exhaust Gas Recirculation(EGR)DOC+DPF+SCR

NTDE Exhaust Treatment Systems —Particle Removal and NOx Reductions

NOx PM NOx

Key to Emissions Reductions in NTDE Wall-flow Diesel Particulate Filter

Trapped PMCell Plugs

Exhaust(PM, CO, HC)

Enter

Porous Ceramic Wall

Exhaust (CO2, H2O)Out

Adapted from MECA May 2000

Reductions:95+% PM

80 to 100% HC, CO80 to 99+% toxins

Emission Proportions

Hesterberg et al., ES&T 42:6437-45, 2008, data from Table 1: transit bus. H2O estimated, see last slide

Advanced Collaborative Emissions Study (ACES)

• Comprehensive Joint Industry and Government Study of NTDE

• Directed and Managed by HEI and CRC• Emissions Characterization and Health Effects

Studies of 2007 NTDE Engines• Emissions Characterization Complete in 2009• Short-term Animal Studies Under Analysis• Ongoing Long-term Animal Bioassay

ACES Hyrdocarbon Testing Results

14

ACES PM Testing Results

15

NTDE: Lower Particulate Emissions

CARB Study: Herner et al., EST 43:5928-5933, 2009, data from Table 2. Transit Buses: UDDS Test Cycle

TDE

NTDEPerc

ent

of T

DE

NTDE: Lower Particulate Numbers

ACES Study: Khalek et al., CRC, 2009.

PM Composition and Mass Comparisons

TDE, NTDE, CNG: Lanni et al., SAE 2003-01-0300, 2003. Transit Bus. Gasoline, Steady State: Schauer et al., Aerol Sci Tech 42:210-23, 2008. Gasoline vs. TDE

PM: Ahlvik 2002.

Most of the Toxic Air Contaminants in TDE are Not Found in NTDE

• Aniline • Antimony compounds • Arsenic • Beryllium compounds • Cadmium • Chlorine (chloride)• Chlorobenzene and

derivatives • Chromium compounds• Cobalt compounds • Ethylbenzene • Inorganic lead

• Manganese • Mercury • 4-Nitrobiphenyl • Nickel • Selenium • Styrene • Xylene isomers and mixtures • o-Xylenes • p-Xylenes • m-Xylenes

Ullman et al, SAE 2003-01-1381, 2003

Polycyclic Aromatic Hydrocarbons

Hesterberg et al., ES&T 42:6437-45, 2008.

VOCs and Aldehydes

NTDE: Lower for Polycyclic Aromatic Hydrocarbons and Volatile Organic Compounds (VOCs)

NTDE Reduces Emissions Across a Broad Spectrum of Compounds

Category Reduction Relative to TDESingle Ring Aromatics 82%

PAH 79%

Alkanes 85%

Hopanes/Steranes 99%

Alcohols & Organic Acids 81%

Nitro-PAHs 81%

Carbonyls 98%

Inorganic Ions 71%

Metals & Elements 98%

Organic Carbon 96%

Elemental Carbon 99%

Dioxins/Furans 99%

Khalek et al. 2010, Table 6

NTDE: Lower for Most Regulated Emissions Also Similar or Better than CNG or Gasoline

Hesterberg et al., ES&T 42:6437-45, 2008. Data from Tables 1 &4. US EPA Standards.

TDE

(2010 Std)

NTDE Particulate Mass Emissions Similar to CNG and Gasoline Vehicles

Hesterberg et al., EST 42 (17), 6437–6445, 2008, data from Table 1. Transit Buses

Compared to CNG VehiclesAhlvik, Vägverket, Publikation 2002:62 2002, data

from Figure 12. Passenger cars

Compared to Gasoline Vehicles

EC/TC Ratio for NTDE PM Similar to CNG and Gasoline Fueled Vehicles

CARB Study: Holmen and Ayala, EST. 2002, 36, 5041–5050, diesel and CNG transit buses. Schauer et al. Aerosol Sci.

Technol. 2008, 42, 210-223. Gasoline passenger cars.

NTDE: No Acute Toxicity in Animals

McDonald et al., Env Health Perspectives 112:1307-12, 2004, developed from Figures 2-4.

Clinical Toxicity Differences: TDE and NTDE

• TDE at high inhalation exposures in human volunteers resulted in – Abnormal thrombus formation and – Abnormal vasodilation

• Similar dilutions of NTDE did not produce those effects in human volunteers

Barath et al. Am J Respir Crit Care Med 2009, 179, A1634. Lundback et al. Am J Respir Crit

Care Med 2009, 179, A1633

Testing Results DemonstrateFundamentally Changed Composition of NTDE

• PM levels in NTDE are more than 100-fold lower than in TDE

• NTDE is chemically very different from TDE

• NTDE emissions are similar to or lower than CNG or gasoline emissions

• Biological effects of TDE in human and animal studies are not observed with NTDE

NTDE Requires Paradigm Shift in Views On Diesels and Air Pollution• NTDE provides near-zero emissions of pollutants of

concern and are comparable or better than gasoline and natural gas emissions

• Greater than 99% reduction in PM mass and numbers• NTDE PM Composition

– Almost No Black Carbon or Elemental Carbon– Almost No Solid Particles– Primarily Composed of Sulfates– Near Zero Levels of other HAPs

• Clean Diesel is a Reality Today

Implications for New Jersey Air Quality• Introduction of NTDE Will Reduce Ambient Levels of PM

and HAPS and Lessen Multipollutant Exposure• State Regulators and NGO’s Need to Recognize the

Significant Differences Between NTDE and TDE in the State’s Clean Air Programs and Initiatives

• Little Value in Additional Studies of TDE – NTDE is Available and Being Introduced Today

• State Programs that Accelerate the Transition to NTDE can be useful in reducing ambient pollutant levels and improving Air Quality throughout the State.