SCR Engine Development at VOLVO

Volvo Bus Corporation

Volvo Bus Corporation - M Brown2005-11-24, Israel SCR

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SCR Engine Development at VOLVO

• Presentation Content

Volvo Environmental CareEuro # engine developmentEGR and VolvoEGR v SCR decision criteriaSCRT experienceSCR System TechnologySCR engine DevelopmentAdblue & LogisticsConclusions

Maurice BrownEuropean City bus Product ManagerVolvo Bus Corporation



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Our Core Values

Quality Safety Environment

We use our expertise to create transport-related products and services of high quality, safetyand environmental carefor demanding customers.



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Euro 1

1993

Certificationof the engine

Euro 2

1996

Conformity of production

Euro 3

Oct2001

Defeat device language

Euro 4

Oct2006

Durability, On Board Diagnostics No. 1, Anti-tampering, In-use testing programme

Euro 5

Oct2009

On Board Diagnostics No. 2. NTE, In-use compliance

Legislation – not only emission levels



42005 2006 2007 2008

Euro 4 step IMandatory

Driver warning if:

• > 5 g. NOx/ kWh

40% torque reduction if:

• > 7 g. NOx/ kWh

Euro 4 step IIAdditional

requirement

Driver warning if:• AdBlue tank is empty• Dismounted catalyst • Lack of AdBlue dosing

Certificationbefore Oct 1 -05

Oct 1 Oct 1 Oct 1

Euro 4 legal requirement

Certify new engines for Euro 4



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Exhaust Emission Standards

PM (P

artic

ulat

e M

atte

r) [g

/kW

h]

Euro 3 (2001)

Euro 2 (1996)

Euro 4 (2006)Euro 5 (2009)

2012NOx [g/kWh]

Euro 6 (2012?)

Legislative Demands

Increased injection pressure & retarded engineWhich lowers efficiency but suppresses NOx formation

Phase out 10 litre engineDevelop lower friction components2 new engines 9 & 12 litre with unit injectors

SCR/EGR?



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Volvo 7 & 10 litre VEC system (EGR)

EGR was pioneered by Volvo

2000 – 2003 with over 400 buses built

Conclusion:

Difficult to achieve acceptable PM emission to

allow CRT regeneration at low load/temp cycles



GasGas system + EGRsystem + EGR MG9 CNG EGR Solution

P2/T2 sensorEGR valve

Cooled EGR

Lambda 1Stoechiometric engine3-way catalyst to treat NOx, HC and COUse of EGR (Exhaust gas recirculation) in

order to reduce exhaust temperatures

Advantages:Advantages:Durable concept: Possibility to have EURO6

Emissions levelDevelopment based on a advanced

engineering projectEngine able to adapt with different Natural gas

3-way catalyst



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Volvo EGR solution for USA

• 80,000 EGR’s in service across the USA since introduction in 2002

V Pulse EGR similar the the MG9 CNG engine

+ 4- 5% fuel consumption penalty

Use of an additive is prohibited in the legal framework due to lack of trust on Operators compliance

• To fulfil US ‘O7Volvo will utilise cooled EGR with PM after treatment

This solution has also been introduced in Japan due to late agreement for use of an Additive – The next generation Japanese engines to be introduced in 2008 are likely be SCR according to statements by two domestic manufacturers.

VGT (variable geometry turbocharger) will be used in the new generation engines



SCR technologySCR technology

SCR - Selective Catalytic Reduction

Selective

Removes NOx in the presence of oxygen

Catalytic

Decreases the activation energy for the chemical reaction which Enables reaction at + 200 °C when amonia is released from the Adblue solution

Reduction

Reduces NOx by 75% - 95%



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Incentive Euro 5 SCRT 340 bhp 12 litre

• Introduced in April 2003 with 27 test buses on the Swedish west coast

• Denox 1 system with air assisted injection and non cooled injector

• 100 buses equipped with this solution and are all operating well

• Adblue consumption is approx 2 – 2.5% due to the lower Nox reduction of the base Euro 3 engine

• Good solution for Euro 3 – 5 due to lower Nox reduction

• No reduction of fuel consumption + Adblue cost

Note: 1% Adblue = -1 gm NOx approx



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Volvo CRT™/SCR system

• Meets the proposed Euro 5 emission standard• 27 buses in field test since April 2003• Market introduction in late 2004• 12 l Euro 3 engine 340 Hp for city/intercity

application

Modular after treatment system

CRT

Clean up catalyst

SCR

AdBlueinjection

Open loop system



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Part

icul

ates

–g/

kWh

NOx – g/kWh0 104 6 8 12 142

0.10

0.08

0.06

0

0.04

0.02

Trade-offPresent

HD Diesel

CooledEGR

EU4EU5

DPF

SCR η=80%

EU3

SCR η=65%

Exhaust Emission Strategy - HD Diesel - Europe



Comparison SCR vs. Cooled EGRComparison SCR vs. Cooled EGR

EGR SCRFuel EconomyGreen House Gases (~Fuel Economy)Heat rejection and Chassis CoolingPackaging (installation dependent)WeightEngine durabilityFuel flexibility (Sulphur)Urea need (On-Board and Infrastructure)Oil Drain IntervalChassis System CostDevelopment cost

Source: Volvo Powertrain, September 2005



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Power plantsEstablished technology since 1970. Possibility to reach 95% NOx-conversion with NH3 .

Marine applicationsCatalytic converters for marine applications to meet NOx-emission levels <2 g/kWh.

Heavy duty vehiclesTest around the world, mainly Europe.Meet legal requirement of NOx-emission <3,5 →2 g/kWh.




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Chemical reaction with SCR (simplified)

In hot exhaust:2NH3

In SCR catalyst:2N2 + 3H2O

From engine:NO + NO2



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• 32.5 % urea solution in desalinated water pH value of 9.0-9.5

• A stable, colourless water-like fluid

• Urea is made of ammonia and CO2

• AdBlue composes slowly to ammonia and carbon dioxide in room temperature

• Freezing point = -11°C

• DIN 70070 standard to ensure consistent quality

• AdBlue is not a hazardous substance

• There are no known health hazards related to handling of AdBlue solution

• Urea is produced in large volumes, stable price levels

• AdBlue ¢ 50 € - ¢ 80 € per litre

AdBlue



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Global production of Heavy Duty Diesel Engines 2004*

Volvo Powertrain

DC Powersystems

Weichai Power

Caterpillar

Cummins

Scania

MAN

Yaroslavl

* Engine Production 2004, 9 - 18 litre (excluding licensees / JV’s)

161.000



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New Heavy Platform - common technology

• One Cylinder Head• Overhead Camshaft• Four Valves per Cylinder• Central Vertical Injector• Electronic Unit Injectors• Electronic Management System• Rear End Transmission• Integrated Engine Brake• Wet Liners



19-202468

101214161820222426g

7 0 6 5 6 0 5 5 5 0 4 5 4 0 3 5 3 0 2 5 2 0 1 5 1 0 0 5 0 0 0 5 1 0

Euro 4 Engine Features

Injection system

• Injector Type : E3

• Same packaging as former E1 version.

• Injection pressure : 2000bar

• Opening and closing pressure : flexible

• Multiple injection capability

• Rate shaping and multiple injection capability

Benefits:

• Euro 4 ultra low particulate emissions levels can be reached without filter.

• Reduced noise and improved cold startabilitythanks to pilot injection capability.



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Electronically controlled Turbocharger

• Water cooled - Insulated

• Machined from solid compressor wheel

• Closed loop electronic control of the waste gate, replacing the former mechanical boost pressure control.

Benefits:

• Full flexibility to control waste gate opening and thus boost pressure

• Precise adjustment of the air quantity into the engine in all operating conditions, for improved transient response, better fuel economy and lower emissions.

Air valve unit



Mapped for city bus & coach applications

Volvo EURO4 Engine

Specific needs of a city bus and coach applications have been integrated in the performance development

• Using detailed analysis of bus and coach driving conditions the engine was optimisedwhere it is used, leading to decreased fuel consumption.

-500

0

500

1000

1500

2000

0 500 1000 1500 2000

600

700

800

900

1000

1100

1200

1300

1400

1500

1600

1700

- 3 0 0

-1 5 0

0

1 5 0

3 0 0

4 5 0

6 0 0

7 5 0

9 0 0

1 0 5 0

1 2 0 0

1 3 5 0

1 5 0 0

1 6 5 0

S P E E D

T O R Q U E

London driving duty cycle analysis



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Clean-up catalyst for removal of NH3 to avoid smell

AdBlue injector+ temp sensor

AdBlue

AdBlue tank

SCR catalyst & muffler

AdBlue pump and injectionsystem control unit

NOx sensor

AdBlue level & temp sensor


Upstream catalytic converter



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Temperature sensor

AdBlue pump and dosing unit

NOx sensor

Components for SCR system – AdBlue Pump and Dosing Unit and sensors



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AdBlueInjectionnozzle

Temp sensor

SCR – Muffler and AdBlue injection

Pre Catalyst -Standard on all 9 litre engines and 340bhp 12 litre engines

NOx sensor

AdBlue injection nozzle



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AdBlue tank and filling neck

The industry has agreed on a automotive AdBlue tank filling neck insert standard to facilitate sealed depot system

Filling neck insert drawing.B = 43.5 -/+0.1 mmC = > 26.8 mm

B

C

AdBlue tanks 40 60 l

Level Sensor & temp sensor



SCR technologySCR technology



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AdBlue Usage Range

COACH• 40 litre tank based on 4% usage and diesel consumption of 28.2 l/100km

(30l x 94%) = 28.240 x 25 / 28.2 x 100 = 3546km max range

• 60 litre tank based on 4% usage and diesel consumption of 28.2 l/100km60 x 25 / 28.2 x 100 = 5319km max range

GENERAL• 40 litres of AdBlue is equivalent to 960 litres of diesel fuel consumption for

Euro 4 and 950 litre for Euro 5



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• Rapid expansion of public systems

throughout Europe• Major oil companies develops

infrastructure (Total, Shell, OMV)• Spill free filling

AdBlue filling – Fuel stations



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• Several suppliers of AdBlue within Europe • Tailor made solutions for depot filling• Volvo partner YARA can support customers with

infrastructure and AbBlue supplies• Spill-free coupling offers AdBlue filling integrated in

atomised depot system for diesel fuel

AdBlue filling – Depot option



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Emission levels Euro 4

0.46

1.5

3.5

0.020.0040.12

2.41

0.0110.01 0.04

2.02

0.0130.010.10

3.01

0.0150

0.5

1

1.5

2

2.5

3

3.5

4

HC CO Nox Pt

g/kw

H Euro 4 normsD7E levelD9B levelDH12E level

Euro 4 Emission Levels



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Future Euro 5 development

Lower Consumption & Emissions• Rate shaping and multiple injection with E3 injector• Higher injection pressure at lower revolutions• Higher efficiency SCR from 80% to 90+%• Improved gas exchange within the exhaust and inlet systems

Lower Fuel consumption• Higher combustion peak pressure + 200bar

Stronger base engine block & cyl. Head

Lower Emissions• More optimised control with additional engine and SCR sensors



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In Summary - No Compromise

• SCR delivers

Low emissionsLower Fuel consumption min 3 – 7% Longer maintenance IntervalsEuro 5 capability from production start in 2006Euro 4 upgradeable to Euro 5 without hardware changesWith Euro 6 generation even better fuel economy



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and finally….

….Thank you for your kind attention

Documents

SCR Engine Development at VOLVO