Scr Mueller

7/28/2019 Scr Mueller

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Experience with SCR Technology for DieselExhaust Emission Control of Trucks in Asia,

Europe and North America

Gary Keefe and Raimund Mueller

Bangkok, February 1, 2001

Motivation for Diesel Engine Emission Control

Human health impact

Photochemical smog Acid rain Human health impact

Human health impact

Greenhouse gas - climate change

Photochemical smog

EngineEmissions

HC

NOx

PM

CO

CO2


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Why Reducing Nitrogen Oxides?

Nitrogen Dioxide (NO2)

from the Exhaust Gas

Ozone forms and is inhaled by persons

Sun effect

Nitrogen Monoxide

(NO)

Atomic Oxigen (O)

Molecular Oxigen (O2)

SCR Reactions with Reducing Agent -Urea

Hydrolysis-Reaction: (NH2) 2CO + H2O 2 NH3 + CO2

SCR-Reaction:

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

8 NH3 + 6 NO2 7 N2 + 12 H2O


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Applications of SINOx Catalysts and Systems

Power Plant Truck

Greenhouse Fertilizer/CoGen

Incinerator

Marine Propulsion

Railroad Engine

Diesel Car

Stationary Diesel

SINOx -Catalysts

Future Emission Standards for Commercial Vehicles

and Market Requirements

Source: Moser et. al.NOx - g/kWh

0190

200

210

220

230

1 2 3 4 5 6 7

Marketrequirement

Legislative

requirement(NOx)

Trade -off with currenttechnology (EU3/US 98)

B S F C

- g / k W h

0

0,1

0,2

0,3

0,4

P a r

t i c u

l a t e s -

g / k W h

2007

2004/2005

2008

1998/2000EUUSJ

Worldwide exhaust emission standards for HD diesel engines beyond 2000


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Exhaust Emission Control Motivation: Diesel Trade-Off

NOx-Emissions [g/kWh]

98632100

1074 5

0,04

0,06

0,08

0,10,12

0,14

0,16

0,18

P M

- E m

i s s i o n s

[ g / k W h ]

0,02

NOx/PMDPF

EGR &Combustion

SINOx

E n g i n e ( P M - o p t )

NOx/BE

S p e c i

f i c

F u e l

C o n s u m p

t i o n

[ g / k W h ]

Emissions-Reduction Potential with SINOx System

Increase of engine-out NOxemission due tofuel efficienttuning, for lowPM emission

Improvement of

BSFC over EURO 3 engineattainable

Emission data in g/kWh

BSFC0

2040

60

80

100

120

140

160

180

200

NOx HC PM

R e l a t

i v e

E m

i s s i o n

i n %

E

5

9

1,8

0,660,6

0,12

0,1

0,03

0,02

80% NOx-reduction

80% HC-reduction

30% PM-reduction

SINOx Capability EURO 3 EnginePM & BSFC optimi zed engineOptimized engine w/ SINOx


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The SINOx System for Trucks

Urea Dosing Unit,Urea and Diesel tankintegrated in one unit

SCR-catalyst integratedin series silencer

base-metal catalyst ceramic monolith cat.volume 30 ltr.

200 cpsi

12 l HD-Diesel engines 6-cylinder 400 hp class

diagnosis

SCR-Catalyst

NOx,O2

reducingagent

(NH2) 2CO

purifiedexhaust

N2,H2O

Urea-DosingUnit

exhaust

operatingdata

(NH2) 2COEDC

ECU DCU

engine

Characteristics of SINOx SCR Systems

Active emission control system integrated solution - Not just an Add-on communication between engine and urea dosing unit via CAN bus integration into the vehicle infrastructure (pressurized air, electrics)

Resources Diesel fuel with S < 0,15% 32,5% solution of urea as reducing agent

Temperature range of exhaust: gas 200...550C (without oxidation catalyst) no or slight increase of exhaust backpressure compared to standard silencer combination with particulate filter feasible if desired for special applications

Function


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Urea distribution infrastructure concept Industry Committee established with members including oilindustry, vehicle and engine manufacturers ureamanufacturers and Siemens:

Step 1- Refilling urea at truck home yard

Step 2 - Refilling urea at main truck stops locatedalong the major highways

Step 3 - Refilling urea at the gas stations Urea Pump Station

Urea Charateristics: non-hazardous, non-explosive, non-toxic released as a food-additive lowest water polluting classification

Reducing Agent Aqueous Urea

Urea - Applications

UREA

Agriculturefertilizer feed

Water industrynutritive substance for the biologicaltreatment of wastewater

Power industry

reducing agentfor exhaust gas

Chemical Industryraw material for:

UF-resinsUrethanesand many others Food processing

for chewing gumproduction

Medical andpharmaceutics for theproduction of:

barbituratesdiureticsspecial injury bandages

Other industriesauxiliaries in:

chipboard industrytextile industrycoolant lindustrycosmetics industry

There is no shortageof urea


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SINOx System - Field Demonstration

Total mileage: 21 trucks 6.099.000 kmMax. mileage of single vehicles: 524.000 km

(Status: 2000-03-27*)

*) 2nd roadtest finished1999-12-31. Some vehiclesareoperatedfurtherfor longtermtesting

Measurements

Investigations:

on the road (vehicle): NOx-reductionUrea consumptionmechanical durability

in lab reactor (SCR-catalyst): activity (NOx-reduction) = f (mileage)physico-chemical measurements(surface area, composition, etc.)

on the test bench (silencer): NOx-reduction at start (ESC, ETC)NOx-reduction at end (ESC, ETC)


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0

0,004

0,008

0,012

0,016

0,02

P M [ g / k W h ]

total PM soluable insoluable0

0,004

0,008

0,012

0,016

0,02

P M [ g / k W h ]

total PM soluable insoluable

PM and NOx emissions - ESC test w/12 ltr. HDE +

SINOx

0

2

4

6

8

10

12

N O x

[ g / k W h ]

NOx

Engine out emissions after SINOxEngine out emissions after SINOx

- 81%

PM and NOx Emissions - ETC test w/12 ltr. HDE+SINOx

0

0,0040,008

0,012

0,016

0,020,024

P M [ g / k W h ]

total PM soluable insoluable0

24

6

8

10

12

N O x

[ g / k W h ]

NOx

Engine out emissions after SINOx

0

0,0040,008

0,012

0,016

0,020,024

P M [ g / k W h ]

total PM soluable insoluable

- 86%


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On-board NOx-measurement on mixed highway

Time in seconds

Highway Section Bamberg Redwitz

N O x -

C o n c e n

t r a t

i o n

i n p p m

0200

400600800

100012001400160018002000

0 750 1500 2250 3000

NOx conversion: 71.2 %NOx conversion: 71.2 % NOx before Cat.

NOx after Cat.

NOx before Cat.

NOx after Cat.

Results of Measurements

Measurements were done and reported by TV Automotive, Germany

1st demonstration program: 0 km 130,000 km remark

NOx reduction on-road: 56% 54% constant within accurarcy

Urea consumption fleet average 4.1 % of diesel fuel consumption

2nd demonstration program: 0 km 272,000 km remark

NOx reduction ESC cycle: 65% 63% constant within accurarcy

NOx reduction ETC cycle: 70% 71% constant within accurarcy

NOx reduction on-road: 74% measured after 212,000 km

Urea consumption fleet average 5.5 % of diesel fuel consumption


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Catalyst activity during field demonstration

Catalyst Activity in accordance with predicted deterioration factor (over 500,000 km)Catalyst total specific surface area and active materials constant over test program Deposition of phoshate on catalyst surface in upstream face of catalyst

0 .6

0 .7

0 .8

0 .9

1

0 1 0 0 20 0 3 0 0 4 0 0 5 0 0 6 0 0

Driv ing Performance [1000 km]

N O x

C o n v e r s

i o n

P e r f .

( r e

l . )

SINOx Catalyst

Fuel optimized engine meeting EURO 4/2 with SCR

Engine modification to EURO III engine for best fuel economy (BSFC)

NOx & PM Emission below EURO 4/2 in ESC and ETC

Program by VROM, AVL, Deutz, Siemens(Source: AVL, Cartellieri et. al. )

0,0

2,0

4,0

6,0

8,0

10,0

12,0

Baseline Optimized w /SCR EUROIV/1

w/SCR EUROIV/2

N O x , P M * 1 0 0 i n

180

185

190

195

200

205

210

215

220

225

B S F C i n g

NOx

PM * 100

BSFC


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US truck SCR investigation & demonstration program

-100%-80%-60%-40%-20%

0%20%40%60%80%

100%

e m i s s i o n s c h a n g e

( % )

NOx HC PM CO CO2

cold US-transient hot US-transient OICA

0,00,10,20,30,40,50,60,70,80,91,0

a m m o n

i a s l

i p ( p p m a v g )

NH3

US SCR HD Truck Demonstration Program


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Applying NOx Sensors

0

400

800

1200

1600

0 1 2 3 4 5

NOx sensor output in MV

N O x

( p p m

)Linear correlation betweenchemiluminescent analyzer andNOx sensor

NOx sensors upstream anddownstream of catalyst accurate

0

300

600

900

1200

1500

0 60 120 180 240 300 360

time (s)

N O x

( p p m

)

SCR OFFbefore catalyst

after catalyst

On-road SCR emission reduction measured

w/ NOx Sensors

0

300

600

900

1200

1500

0 60 120 180 240 300 360time (s)

N O x

( p p m

)

Level highway: 77 %Mountain highway 71 %

Urban traffic: 78 %Overall average: 73 %

----- before catalyst ---- after catalyst


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Experience with SCR in Asia

SCR included in Japan Clean Air Program (JCAP)technology assessment - results will be published later this year

Japanese diesel engine and truck manufacturers operateSINOx SCR systems in test cells and trucks

SCR Experience in Japan, Taiwan, South Korea in utilitypower plants, gas turbines and Stationary diesels since the1970s

NOx Reduction in Japanese 13 mode Cyclewith Japanese Diesel HD Engine

0

500

1000

1500

2000

2500

3000

1 2 3 4 5 6 7 8 9 10 11 12 130

5

10

15

20

25

30NOx without SINOx: 10.4 g/kWh

NOx with SINOx: 3.0 g/kWh

NH3 ppm

NOx-Reduction: 71 %

N O x g

/ h

N H 3 p p m

Mode No.


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Monitoring and Diagnosis

NOx sensors have been demonstrated as applicable technology.

Upon commercial availablity and proven long-term durablity NOxsensors

can be useful tool for :+Monitoring Diagnosis Control

Sensors monitor operation and functionality of system components Sensors monitor level and quality/grade of reducing agent

System control unit col lects and interprets sensor data

System control unit transfers information to engine control unit for further evaluation

SCR Trucks becoming available

Field demonstration has proven:

SCR-systems reduce NOx, HC, PM emissionsin test cycles and in real world operation

SCR is a viable technology for trucks

SCR durability in accordance with truckoperation

Whats next: SCR trucks offered by OEMstarting in 20012001


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Customer s benefits using SINOx

Savings in emission-staged road-pricing- those will be implemented according toGovernment decisions in several European Countries 2003

Meeting NOx limits of the two steps Euro 4/1 & 4/2 with the same technologywith fuel efficient Eu 2 engines, lowest PM by adjusted engine tuning & advanced design

Insensitive to fuel sulfur - operation with current standard fuel (500 ppm S)Truck operation outside central Europe or US with low grade diesel fuel also possible

Proven longterm stability and durability (> 500,000 km)

Catalyst system performance is demonstrated to be constant withinmeasurement accuracy

Flow-Through system, truck mobility not at risk

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