Diesel Engine Emissions

STLE Houston Chapter December 2009 Conference

Reginald M. DiasDirector, Commercial ProductsConocoPhillips Lubricants

Reducing Diesel Engine Emissions

• Reduce environmental pollutantsMinimize NOx, PM and HC in tail-pipe emissions

• Reduce greenhouse gasesOptimize combustionIncrease energy efficiency

• Improve quality of lifeReduce risk of health hazards to humans and animals

NA Emissions & Lube Performance

NOx PM Year

On road

0.2Full

0.01Compliance

20072010

Off-road specifications 130-560kW

Tier 4a _ 0.02 2011

Tier 4b 0.4 0.02 2014

1988 6g NOx 0.6g PM 1988CE

CF-4 1991

CG-4

19942002 1998

CH-4CI-4/+

CJ-4

Par

t icu l

a tes

(g/h

p -h r

)

NOx (g/hp-hr)31 2 4 5

0.10

0.25

Path to Emissions Reduction

• Engine StrategiesCombustion optimizationCooled Exhaust Gas Recirculation (EGR)Variable Geometry Turbo-charging (VGT)High Pressure Common Rail (HPCR) Fuel systemElectronic controlsCrankcase filtration

• Exhaust After-treatment StrategiesCatalyzed Diesel Particulate Filter (DPF)Diesel Oxidation Catalyst (DOC)Selective Catalytic Reduction (SCR)NOx adsorber

• Fuel: Ultra Low Sulfur Diesel

Emissions Impact on EnginesPa

rtic

ulat

es

NOx

Turbochargers & Intercoolers

Fuel changes

Retarded injection, piston design changes

EGR

CRTOXICAT

De-NOx CAT

SCR

ENGINE DESIGN

AFTERTREATMENT

SCR = Selective Catalytic ReductionCRT = Continuously Regenerating Trap

Exhaust Gas Recirculation-EGR• Return cooled exhaust gas

back into air intakeGases already used by engine

are low in oxygen (reduce oxygen content in air intake)Exhaust gas absorbs energy

during combustion to lower combustion temperature

• Less Nitrogen Oxides formedLess oxygen to react withLower cylinder temperature

• Increases operating temperature

• Reduces fuel economy

Diesel Particulate Filter• Fail safe, Diesel Particulate

Filter (DPF) used to capture particulate matter in exhaust

• DPF may include active or passive regeneration

Diesel Oxidation catalyst (DOC)Inline or post in-cylinder fuel

injection to burn out PMReduces fuel economy

• Closed Crankcase Ventilation (CCV) to reduce volatile emissions

• ULSD required for use in all new engines- reduce pollution Exhaust

Oxidation Catalyst

Diesel Particulate Filter (DPF)

Engine Oil Quality Improvement

Oil Consumption

Valve Train Protection

Bearing Protection

Soot ControlPiston deposits

Shear Stability

Emissions Friendly

CJ-4CI-4 PlusCI-4

CJ-4 : Soot Control in T-11 TestMack T-11 Soot Dipserancy Engine Test

0

12

24

36

48

1 2 3 4 5 6 7 8

% Soot in Oil

Visc

osity

Incr

ease

(cSt

)

Excellent Soot Control

Test Limits: 12 cSt Viscosity Increase

Mack T-11Test Ref Oil

API CI-4Oil

API CJ-4 Candidate Oil

Recent Engine & Lubricant Changes

• 2002 EGR implemented to achieve NOx targetsCI-4 Introduced to address increased soot from by EGR. CI-4 + launched in 2004 to mitigate soot caused viscosity increase in some OEM products.

• 2007 Enhanced EGR & DPF after-treatment deployedDPF to meet the 0.01 g/bhp PM limit. NOx targets are phased in.CJ-4 introduced at lower ash and SAPS limits to mitigate concerns over potential DPF blockage and catalyst poisoning.

• 2010 EGR and SCR typically deployed to further reduce NOx. DPF use will continue to control PM.

Emissions limits remain the same, but full compliance for, both PM and NOx, required across the whole fleet.

SCR for 2010 Emissions Compliance

DOCDPF SCR

DEF

AmmoniaSlip

Catalyst

DPF = Diesel Particulate Filter

DOC = Diesel Oxidation Catalyst

DEF = Diesel Emissions Fluid (30 % aqueous UREA solution)

SCR = Selective Catalytic Reduction

SCR for 2010 Emissions Compliance

4NO + O2 +4NH3 4N2 + 6 H2O

2NO2 + O2 +4NH3 3N2 + 6 H2O

4NO + O + 2[CO(NH ) ]2 2 2 4N + 2CO + 4H O2 2 2Source: SWRI

280 C Min temperature

Urea Decomposition to Ammonia

SCR

SCR

SCR for 2010 Emissions Compliance

• Major NA and European OEMs committed SCR (selective catalytic reduction) use with UREA treatment to meet Tier III emissions

Navistar is the only exception- expects to achieve emissions with enhanced EGR (cost competitiveness !)

• SCR is a bolt-on device in addition to currently used DPF and DOCOn board aqueous Urea dispensing method such as a fill-able tank Aqueous urea to be available at dealerships, maintenance shops and service centersOEM and commercial after-market service providers (e.g. Pilot and Flying J) have announced plans to supply Urea

• SCR will be a tamper-proof systemBy EPA rule, it will be a tamper proof system with reduced power, limp-home ability to cover emergency.

• OEMs will specify use of API CJ-4 quality lubricants in their 2010 model engines equipped with SCR

Why Interest in SCR?Reduction-PotentialPM NOx HC CO2 Costs Potential Risks

• Ash deposits• Catalyst deactivation• Fuel dilution• Regeneration•EGR to reduce NOx

• HC Increase• Catalyst deactivation• Long term degradation•Increased fuel use from rich NSC cycling

• Urea Infrastructure• Urea consumption• Catalyst deactivation• Low temp. performance

+ +

+ + + +

+ + + + +

0 0

0

- - -

-- - - - -

- - - -

DOC DPF

Diesel Particulate Filter System

NSC DPF

NOx –Storage System

DOC DPF SCR

SCR Urea System

SCR for 2010 Emissions Compliance

• AdvantagesEngine builders may reduce EGR rateRecapture fuel economy lost to enhanced EGR Reduce heat discharge- easier on cooling systemEngine oil exposed to lowered operating temperature

• DrawbacksIncreased weight of add-on device (200 -400 lb)Increased cost for new deviceIncreased maintenance and added operating costRisk of running out of DEF (urea solution)

Potential SCR Deactivation:

• High temperature water, in engine exhaust, may cause hydrothermal de-alumination.

Loss of Al sites may reduce NH3 storage and less SCR activity• High temperature leads to sintering, loss of active metal

surface areaLess activation of NO to NO*. SCR process may slow down.

• Poisoning and blockage –Reversible

• Coke, HC’s, N- compounds• Removable in hot (>600 C) conditions

Irreversible• Lubricant borne components: Ca, P, Zn

What about Off-Highway?• Duty cycle considerably more variable for off-highway applications. • Difference exists in low speed off-road application versus an on-

highway line-haul application. The air-flow and hence cooling will be greatly reduced.Exhaust temperature may be lower which will impact the DPF regeneration strategy Space may not be available to add an SCR catalyst system

• Technology to meet the Tier IVa and IVb emissions targets will vary depending on varied duty cycles and applications.

For PM emissions at 0.02g/bhphr DPF will have a wide utilityFor NOx compliance EGR will be used, but SCR will have a role to play where it can be deployed, for example in power generation.

• DPF use will drive increased usage of CJ-4 lubricants in off-highway applications.

88

77

66

55

44

33

22

11

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

NOxNOx(g/hp-hr)

PM(g/hp-hr)

<25 hp 25-75 hp 75-175 hp 175-750 hp >750 hp 15 ppm S

fuel

50%

PM

NOxNOx

0.30

0.02

3.5NOx+NMHC

5.6NOx+NMHC

0.01 0.010.030.30 0.30

Significant reductions in PM and NOx

0.5

2.6

0.02

generator sets

Tier 4 Off-road Emissions 2009-2013

Emissions Control -Global Synergies

2002/2004 2006/07 2010 +

N. America EGR EGR/DPF EGR/DPF/SCR *

Europe SCR SCR EGR/DPF/SCR

Japan EGR/DPF EGR/DPF/SCR EGR/DPF/SCR

Source: DEER Conference 2005/9 * - Navistar is following a unique approach for 2010. Note that Europe is using a Vanadia based catalyst system which differs from that proposed for North America in the 2010 timeframe.

DIESEL EMISSIONS- CARB Directives

• Accelerated introduction of ULSD relative to US EPA compliance timeline

• Accelerated implementation of emissions regulations

Stringent emissions rules in non-attainment areasRetrofit hardware to meet 2010 emissions standardsNo-idle requirements

EPA Diesel Sulfur Regulations

Who Covered Fuel 2006 2007 2008 2009 2010 2011 2012 2013 2014

Large Refiners & Importers

ON-HIGHWAY 500 ppm

15 ppm

15 ppm

15 ppm

15 ppm

15 ppm

15 ppm

15 ppm

15 ppm

Large Refiners & Importers

NON-ROAD 500+ ppm

500 ppm

500 ppm

500 ppm

15 ppm

15 ppm

15 ppm

15 ppm

15 ppm

Large Refiners & Importers

LOCOMOTIVE & MARINE

500+ ppm

500 ppm

500 ppm

500 ppm

500 ppm

500 ppm

15 ppm

15 ppm

15 ppm

Small Refiners & Other Exceptions

NON-ROAD, LOCOMOTIVE & MARINE

500+ ppm

500+ ppm

500+ ppm

500+ ppm

500 ppm

500 ppm

500 ppm

500 ppm

15 ppm

Except in California, compliance dates for Non-Road, Locomotive and Marine fuels in the years indicated are: June 1 for refiners and importers; August 1 downstream from refineries through fuel terminals; October 1 for retail outlets; and December 1 for in-use.

In California, all diesel fuel transitioned to ULSD in 2006. Locomotive and Marine diesel fuels were required to transition to 15 ppm ULSD effective January 1, 2007.

Non-Road Diesel fuel Standards

Line Haul & Passenger Locomotives

Source: http://www.epa.gov

Standards Apply To Take Effect in Year PM NOx HCRemanufactured Tier 0 & 1 2008 as available

2010 required0.22 7.4* 0.55

Remanufactured Tier 2 2008 as available2013 required

0.1 5.5 0.3

New Tier 3 2012 0.1 5.5 0.3

New Tier 4 2015 0.03 1.3 0.14

* For tier 0 locomotives originally manufactured without a separate loop intake air cooling system, these standards are 8.0 and 1.00 g/bhp-hr for NOx and HC, respectively.

EPA Tier 3 & Tier 4 Standards (g/bhp-hr)

With the use of lower sulfur diesel fuel, most of the major NA Railroads have now switched to lower TBN (9 BN), high performance LMOA Gen V engine oil

Proposed Marine Fuel Changes

2008 2010 2011 2012 2015 2016 2020

4.5% S (HSO)

1.5% S (LSF) 1.0% S (LSF)

3.5% S (HSO)

0.10% S (LSF)

0.5% S (HSO)SeaECA

NOx Tier I (17g/kWhr)

NOx Tier II (14.4 g/kWhr)

NOx Tier III (3.4 g/kWhr) for ECA

IMO directed changes. ECA = Emissions Control Area

Lower TBN Lubricants may satisfy future needs

Diesel Emissions Trends

02468

1012141618

1998 2003 2008 2013 2015

NO

x g/

kWhr

MARINE RR EURO US EPA

CONCAWE report, 3/09 www.concawe.orgExact time scale among segments not matched

Thank you

Q & A