urea scr- the volvo way

Volvo Technology Corporation6130./ Ann W Grant / 5/10/2007 /1

Urea SCR- The Volvo Way

CLEERS Workshop 2007


Ann W GrantVolvo Technology AB

Göteborg Sweden



BUSINESS AREAS at AB Volvo

Volvo Buses

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Mack Trucks Renault Trucks Volvo Trucks

TRUCKS



THE VOLVO GROUP ORGANISATIONAB Volvo

RenaultTrucks

VolvoTrucks

VolvoBuses

VolvoCE

VolvoPenta

Volvo Aero

FinancialServices

BusinessAreas

Bu

sin

ess

Un

its

Mack Trucks

Trucks

3P

Powertrain

Parts

Logistics

Information Technology

Technology



FACTS ABOUT VTEC• We are 381 employees• VTEC turnover is €36M• Established 1969• Innovation Areas- services- production- vehicles- powertrain- electronics- processes & methods

• Innovation Services- intellectual asset management- standardisation intelligence



Volvo diesel engines with



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



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



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)

2012

Euro 6 (2013?)

NOx [g/kWh]

Legislative Demands



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



Engine Optimization and Fuel Consumption• Variation in injection timing

Higher engine-out NOx gives better fuel consumption (~3%)



SCR vs. EGR – Euro 3 baseline

SCR EGRFuel consumption

Heat rejection

Power density

Reliability

Maintenance

Euro 5/6 capability

Total cost



2005 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



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.

SCR - Selective Catalytic Reduction



The selected solution UREA SCR

• Oxidation catalyst upstream (NO2 production)• Cleanup catalyst for removal of NH3 slip



Clean-up catalyst:Removal of NH3to avoid smell

AdBlueinjector

AdBlue

AdBlue tank

SCR catalyst

AdBlue pump and injection system control unit

NOx sensor

AdBlue levelsensor

Muffler

SCR - Selective Catalytic Reduction

Additional catalyticconverter



AdBlue Injectionnozzle

Temp sensor

SCR – Muffler and AdBlue injection

Pre catalyst

NOx sensor

AdBlue injection nozzle

Inlet

Outlet

Inlet



AdBlue tank

AdBlue pump and dosingunit

SCR installation on Volvo B7R/RLE

Lefthand side variant



AdBlue injector NOx sensor

Temp. sensor

SCR muffler

SCR installation on Volvo B7R/RLE SCR system weightbetween100 -125 kg



AdBlue tank and filling neck

The industry has agreed on a automotive AdBlue tank filling neckinsert standard to facilitate sealeddepot system

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

B

C

AdBlue tanks 34, 40 60 l



AdBlue: Urea (NH2)2CO• Meets requirements:

• non toxic, regarded safe to transport, handle and store • Frequently used in other applications

• Fertilizer, food industry …• Water soluble

• > 50% (108g/ 100 ml H2O)• 32,5 % eutectic point

• Weight 60 g/mol• Melting point 135 °C• Meets DIN 70070 standard• Corrosive to certain metals

• (zinc, copper, non alloyed steel)• Produced in large volumes at a stable price

Freezing point °C

-12

-9

-6

-3

00 15 30 45 60

Urea wt%

-11 °C @ 32,5 %



Urea Infrastructure Development:Some European experiences

Basically three avenues for urea distribution• fuel stations and/or truck stops• filling in a fleet depot• Small canisters available for purchase

Automotive Urea Infrastructure• Urea tank to be filled each time diesel is filled• On board diagnostics monitor urea level and notify driver• The infrastructure will be needed to ensure the

compliance to emission legislation• First step is establishment of a minimum infrastructure to

ensure the availability for the first trucks and buses on the market



Adblue urea filling – Fuel stations

• Open system• Major oil companies develops

infrastructure (Total, Shell, OMV)• Slim Line spout nozzle (Elaflex )• Magnetic Ring in the urea tank filler neck

inlet prevents spilling• Public urea filling station (Total Stuttgart )• New stations being added continuously• Website Adblue4you.com shows where

Adblue can be found in certain European countries



Urea filling – Depot option• Sealed / open depot filling system• Spill-free coupling offers urea filling integrated in a depot system

for diesel fuel ( Identic )• Spill free couplings are today used for filling diesel fuel• Volvo partner YARA (Norsk Hydro) can support customers with

infrastructure and AbBlue supplies



Production capacities of urea in 2002Norsk Hydro

Sluiskil, Netherlands750 000 t/yr

Norsk HydroBrunsbüttel, Germany

530 000 t/yrNorsk HydroLe Havre, France

333 000 t/yr

Norsk HydroFerrara, Italy440 000 t/yr

AgrolinzLinz, Austria380 000 t/yr

BASFLudwigshafen,

Germany545 000 t/yr

SKWPiesteritz, Germany

1 041 000 t/yr

DSM AgroGeleen,

Netherlands390 000 t/yr

FertiberiaPuertollano,

Spain135 000 t/yr

Grande ParoisseOissel, France

120 000 t/yr

AdubosLavradio, Portugal

80 000 t/yr

FertiberiaHuelva, Spain

250 000 t/yr

Total amounts in kilotonsAustria 380France 443Germany 2116Italy 440Netherlands 1140Portugal 80Spain 385

Total 4984



Automotive urea demand estimation

• Estimations of automotive urea consumption up till 2012 has been reported by ACEA

• Annual production of urea in 2002 was approximately 5 million tons. Corresponds to approximately 15 million tons of automotive grade urea.

• Automotive grade urea demand in 2012 is estimated to be approximately 3.5 million tons (20% increase in urea-demand)



Some issues in Urea SCR:Mobile measurements and Ad-blue dosing strategies for low temperature performance

• Dosing strategy test to define the best dosing strategy for ad-blue for vehicles operating at low temperatures

• 23 vehicle multiyear durability study of a combined DPF/SCR system in the US using mobile measurements



Basic Chemistry of the SCR system(Selective Catalytic Reduction)

Ammonia reduces NOx in the SCR catalyst:• NO2 + NO + 2NH3 2N2 + 3H2O fast• 4NO + 4NH3 + O2 4N2 + 6H2O intermediate• 2NO2 + 4NH3 + O2 3N2 + 6H2O slow

⇒ NO/NO2 = 1/1 is bestTemperature > 200°C needed

Vanadium oxide

Pla

tinumNOx, NH3 NOx, NH3 NOx

Clean up catalyst remove surplus ammonia to avoid smell

SCR catalyst Clean-up catalyst

Urea ((NH2)2CO) decomposes to ammonia (NH3) and CO2 in hot exhaust gas(>130 °C) through an HNCO intermediate (thermolysis and hydrolysis)



0

100

200

300

400

500

600

0 300 600 900 1200 1500 1800

US kallUS varmETCESC (tidsupp)

Before system

Temperature in exhaust system

0

100

200

300

400

500

600

0 300 600 900 1200 1500 1800


0

100

200

300

400

500

600

0 300 600 900 1200 1500 1800


SCRT (DPF+SCR)

After system



0.00

0.10

0.20

0.30

0.40

0.50

50 150 250 350 450 550 650Temp °C

Freq

uenc

y of

giv

en te

mpe

ratu

re

0.0

0.2

0.4

0.6

0.8

1.0

NO

x co

nver

sion

Present SCR

Active temperature range for SCR catalysts

US cold

US warm

ETC

ESC

Route 85



Urea Dosing strategy tests for lowtemperature operation such as route 85

• Three different engine maps were tested using severaldifferent urea injection timing strategies and dosingamounts

• Simulated city bus route cycle for low temperatureoperation (like route 85)

• Monitoring of both gas phase compounds and particulate matter formation with both FTIR and a state-of-the-art particulate matter measurement

• Balance between NOx conversion and NH3 slip and production of cyanuric acid at too high dosing rates.



0

500

1000

1500

2000

2500

3000

15:38:53 15:41:46 15:44:38 15:47:31 15:50:24 15:53:17 15:56:10 15:59:02 16:01:55

Con

cent

ratio

n (p

pm)

-60

-50

-40

-30

-20

-10

0

10

20

30

40

NH

3 an

d H

NC

O c

once

ntra

tion

(ppm

)

Nitrous oxide N2ONOxAmmonia NH3HNCO

dN/dlogdp /cc

1.E+3 1.E+4 1.E+5 1.E+6 1.E+7 1.E+8

1000

500

200

100

50

20

10

5

Par

ticle

dia

met

er(n

m)

1 201 401 601 801 1001 1201 1401

0.00E+00

1.00E+06

2.00E+06

3.00E+06

4.00E+06

5.00E+06

6.00E+06

7.00E+06

8.00E+06

1.00 10.0 100 1000Dp (nm)

dN/dlogDp /cc

37% NOx conv.



0

500

1000

1500

2000

16:33:36 16:40:48 16:48:00 16:55:12 17:02:24

Time

Con

cent

ratio

n (p

pm)

-60

-40

-20

0

20

40

60

NH

3 an

d H

NC

O c

once

ntra

tion

(ppm

)

Nitrous oxide N2ONOxAmmonia NH3HNCO

dN/dlogdp /cc

1.E+3 1.E+4 1.E+5 1.E+6 1.E+7 1.E+8

1000

500

200

100

50

20

10

5

Par

ticle

dia

met

er(n

m)

1 201 401 601 801 1001 1201 1401

0.00E+00

1.00E+06

2.00E+06

3.00E+06

4.00E+06

5.00E+06

6.00E+06

7.00E+06

8.00E+06

1.00 10.0 100 1000Dp (nm)

dN/dlogDp /cc

77% NOx conv



0.00E+00

1.00E+06

2.00E+06

3.00E+06

4.00E+06

5.00E+06

6.00E+06

1.00 10.0 100 1000Dp (nm)

dN/dlogDp /cc

test 07-03-13, II serie

0

500

1000

1500

2000

2500

11:49:00 11:51:53 11:54:46 11:57:38 12:00:31 12:03:24 12:06:17 12:09:10

Time

NOx, C

O (pp

m)

-20

-10

0

10

20

30

40

50

60

70

HNCO; N

H3 an

d N2O

(ppm

)

Carbon monoxide CONOxNitrous oxide N2OAmmonia NH3HNCO

dN/dlogdp /cc

1.E+3 1.E+4 1.E+5 1.E+6 1.E+7 1.E+8

1000

500

200

100

50

20

10

5

Par

ticle diameter

(nm)

0.00E+00

1.00E-01

2.00E-01

3.00E-01

4.00E-01

5.00E-01

6.00E-01

7.00E-01

8.00E-01

9.00E-01

1.00E+00

11:49:00 11:50:26 11:51:52 11:53:19 11:54:45 11:56:12 11:57:38 11:59:04 12:00:31 12:01:57 12:03:24 12:04:50 12:06:16 12:07:43 12:09:09

spee

d

drive from 11:50 - 12:10 on 070313

0.00

5.00

10.00

15.00

20.00

25.00

30.00

35.00

40.00

800 820 840 860 880 900 920 940 960 980 1000

Time (sec)

N/cc or ppm

0.00E+00

5.00E+07

1.00E+08

1.50E+08

2.00E+08

2.50E+08

3.00E+08

Ammonia NH3HNCO30 - 300 nm5 - 30 nm

Idling

Start of Cycle

Start of urea injection



Four year durability studyof a combined SCR + DPF



SCRT System

SCRT™

Ureatank Front

wheel

Inlet Outlet

Fuel tank

Urea dosing system



•Multi-year gas phase emission testing of a fleet of 23 vehicles•Both engine out and tailpipe measurements using mobile FTIR

•Engine Volvo D12C 12 liter 465 hp @1300 rpm•Total 71.5 liter aftertreatment unit (DPF + SCR)•18-mile simulated distribution route:

0

10

20

30

40

50

0 200 400 600 800 1000 1200 1400 1600

time (sec)

60

70

80

90

100

110

120

vehicle speed (km/h)



FTIR results from on-road tests on the 18-mile routeTruck B228. Tailpipe emissions upstream and downstream of the CEATS system

B228 before

0

1

2

3

4

5

6

7

8

9

10

0 200 400 600 800 1000 1200 1400 1600Time (sec)

CO

2, H

2O c

once

ntra

tion

(%)

Water vapor H2O

Carbon dioxideCO2

B228 after

0

2

4

6

8

10

12

0 200 400 600 800 1000 1200 1400 1600 1800Time (sec)

CO

2 , H

2O c

once

ntra

tion

(%)

Water vapor H2O

Carbon dioxideCO2

B228 before

0100200300400500600700800900

100011001200

0 200 400 600 800 1000 1200 1400 1600Time (sec)

Con

cent

ratio

n (p

pm)

0

10

20

30

40

50

60

70

N2O

, NH

3 co

ncen

trat

ion

(ppm

)

Carbon monoxide CONitrogen monoxide NONitrogen dioxide NO2NOxNitrous oxide N2OAmmonia NH3

B228 after

0

100

200

300

400

500

600

700

800

900

1000

0 200 400 600 800 1000 1200 1400 1600 1800Time (sec)

Con

cent

ratio

n (p

pm)

0

10

20

30

40

50

60

70

NH

3, N

2O c

once

ntra

tion

(ppm

)

Carbon monoxide CONitrogen monoxide NONitrogen dioxide NO2NOxNitrous oxide N2OAmmonia NH3



Summary of Emission Results

Year Average NOxconversion NH3 slip

US07 NTE compliancewithin fleet

(cold)

October 2004 75 +/- 6% 20 ppm 91 %

June 200573 +/- 8%

28 ppm 91 %

June 200661 +/- 12%

30 ppm 70%

Overall durability is very good—Truck mileage varies +/- 150,000 milesSome trucks have driven over 350,000 miles



• Optimized engine with SCR for Euro VI and EuroV

• Infrastructure availability and refilling of Urea • Onboard diagnostics• More work needed for low temperature

applications• Durability, field tests with total

700 000 km driving without major problems• NOx reduction >75% possible

Summary



Special thanks to:

•Volvo Bus Corporation•Patrik Klintbom•Jonas Edvardsson•Miroslawa Abul-Mihl•Lennart Andersson•Lennart Cider•Heije Westberg

urea scr- the volvo way

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