High efficienc efficiency y SCR system system for most effective effective NOx NOx reduction reduction and best best fuel economy economy for on- and off-road off-road applica applications tions Dr. Dr. Ulrich Ulrich Pfahl, Pfahl, Emitec Emitec Inc. Detroit, June 20th, 2012
• • • •
Exhaust Emission Legislation Legislation & Strategies SCR System Layout & Development Requirements Requirements of Urea Dosing System – Air Assisted / Airless Conclusion
Agenda
• • • •
Exhaust Emission Legislation Legislation & Strategies SCR System Layout & Development Requirements Requireme nts of Urea Dosing System – Air Assisted / Airless Conclusion
Agenda
Engine Technology Euro VI
n o i t p m u s n o C l e u F
Engine Technology Euro IV 60 ] h W k / g m 30 [ M P
EU VI
0
EU IV
EU V
High Hi gh Effi Effici cien entt SCR: SCR: > 95 95% % 1
2
3
4
Exhaust Emission Legislations & Technologies Example Example : Commerical Commerical Vehicle Vehicle - ETC
NOx [g/kWh]
6
• • • •
Exhaust Emission Legislation Legislation & Strategies SCR System Layout & Development Requirements Requireme nts of Urea Dosing System – Air Assisted / Airless Conclusion
Agenda
Silencer Silencer
SCR
Euro IV : > 70% NOx efficiency
DOC
SCR
P I L S
Silencer Silencer
Euro V : > 85% NOx efficiency
DOC Hyd.
P I DPF/SCR L S
Silencer Silencer
SCR System Layout & Development
Euro VI : > 95% NOx efficiency
NH3 Formation {(NH2)2CO •7H2O}fl
{(NH2)2CO}fl + 7 H2O
water water evaporation evaporation
{(NH2)2CO}fl
HNCO + NH3
ther thermo moly lysi sis s of urea urea
HNCO + H2O
CO2 + NH3
hydr hydrol oly ysis sis of isoc isocy yanic anic acid acid
NOX Reduction 4 NO + O2 + 4 NH 3
4 N2 + 6 H2O
2 NO2 + 2 NO + 4 NH 3
standa standard rd reacti reaction on with with NO
4 N2 + 6 H2O
“fast“ “fast“ react reaction ion with with NO+NO NO+NO2
100 ] 90 % [ e t a R n o i s r e v n o C x O N
NO2 / NO 50%
80 70 60
NO2 / NO 0%
50 40 30 20 10 0 0
100
200
Tem Te m perature perat ure [°C]
SCR Processes
300
400
NH3 Formation {(NH2)2CO •7H2O}fl
{(NH2)2CO}fl + 7 H2O
water water evaporation evaporation
{(NH2)2CO}fl
HNCO + NH3
ther thermo moly lysi sis s of urea urea
HNCO + H2O
CO2 + NH3
hydr hydrol oly ysis sis of isoc isocy yanic anic acid acid
Adblue ® Droplet
Hitting the Target Surface
Evaporation
Develop System according to Critical SCR Processes :
Good evaporation evaporation of DEF – optimized amount of DEF injected per time per unit targeted area , in order to minimize the temperature loss in the system
Optimum hydro hydrolysis lysis of isocyanic isocyanic acid – Preference for Hydroly Hydrolysis sis Catalyst
Good uniformity uniformity of NH3 – Optimized Mixing Mixing Tube Tube Design
SCR Processes
• • • •
Exhaust Emission Legislation Legislation & Strategies SCR System Layout & Development Requirements Requirements of Urea Dosing System – Air Assisted / Airless Conclusion
Agenda
• Air Assisted / Airless • Mass Per Droplet Size
Key Considerations of Urea Dosing System Design
Droplet Size Distribution
Droplet Mass Distribution
1.2
100
n 1 o i t u 0.8 b i y r t t i s s i 0.6 D n e e D v i t 0.4 a l e R 0.2
%80 s s a M 60 e v i t a 40 l u m u 20 C
0 0
20
40
Droplet Size in Microns
60
0 0
10
20
30
40
50
60
Droplet Size in Microns
Air assisted assisted SCR System System:: Measured Measured Droplet Size - and Droplet Droplet Mass Distribution at 20 l/min Airflow
5 µm µm
< 5 mm
30 µm
70 µm
1110 mm
6100 mm
Evaporat Evaporation ion dist distance ance requ. requ. at 200 kg/h kg/h exhaus exhaustt mass mass flow flow @ 430 °C Technical University Munich, tube-Ø 55 mm
• Air Assisted / Airless • Mass Per Dropl plet et Size • Temperature • Layout – Exhaust Exhaust Gas Temperat Temperature ure ( injector location, insulation), Injection Strategy
Key Considerations of Urea Dosing System Design
OxiCatalyst
600
Urea Dosing
SCR
500
] C ° [ t a 400 C R C S 300 m a e r t s p 200 u . p m e T 100
EU V Engine
EU VI / US 2010 Engine
0 0
20 0
40 0
60 0
80 0
10 00
1 20 0
140 0
1 60 0
1 8 00
Time [s]
New Conditions for HD Truck Catalyst Systems; Exhaust Gas Temp. Temp. EU V / US 2010 (EU VI); 13mode steady state
Exhaust Temperature EHC Not Active Ehxaust Temperature EHC Active Exhaust Mass Flow 300
3000
275
2500
] C ° [ 250 e r u t 225 a r e p m200 e T
Benefit in Temperature with EHC
2000 1500 1000
175
500
150
0 0
25 0
5 00
750
1 0 00
1250
150 0
1 750
] h / g k [ w o l F s s a M t s u a h x E
2000
t [sec]
Temp Tempe eratu rature re Profi rofile le of of a Comm Comme ercia rciall Vehi Vehic cle with with and with withou outt Elec Electr tric ical ally ly He Heat ated ed Ca Cata taly lyst st (EHC (EHC): ): Cit City y Dri Drivi ving ng Cy Cycl cle e
• Air Assisted / Airless • Mass Per Dropl plet et Size • Temperature • Layo Layout ut – Ex Exha haus ustt Gas Gas Tem Tempe pera ratu ture re ( inje inject ctor or location, insulation), Injection Strategy • Mixing Mixing Pipe Pipe Design Design - Tasks • Avoid Deposit formation • Good Uniformity • Creation of NH3
Key Considerations of Urea Dosing System Design
100 10 0
NOx-Reduction [%]
60
95
50
90
40
85
30
80
20
75
10
70 0. 88 0. 9 0. 92 0. 0 . 94 0. 0 .96 0. 0. 98 NH3-Uniformity
1
NH3- Slip Slip [ppm [ppm]]
0 0.88
Alpha = 1.00
0. 9
0. 92 0.94 0. 96 0. 98 NH3-Uniformity
Calculated NOx-Reduction and NH3 Slip as Function of NH3-Uniformity and DEF-Dosing Rate
1
100 90 % 80 , y 70 c n 60 e i c 50 i f f 40 E x 30 O N 20 10 0
High Load Points B50
A5 0
B50
A50
DEF Injector – Initial Layout Layout
A2 5 B1 0 0 B2 5 ESC Load Point
C100
C2 5
100 90 % 80 , y 70 c n 60 e i c 50 i f f 40 E x 30 O N 20 10 0 A2 5 B1 0 0 B2 5 ESC Load Point
C100
C2 5
DEF Injector Injector – New Layout Layout
NOx Reduction @ selected US US EPA EPA 13mode / ESC load points points
100 98 96 y c n e 94 i c i f f E x 92 O N 90
Test conditions: c onditions:
88 86 0.85
0.9
0.95 Alpha (-)
constant speed / torque
•
constant temperatu temperature re and massflow massflow and exhaust gas condition
•
exhaust exha ust gas ga s 714 kg/h, T = 420 °C, NO x = 543 ppm; NO2/NOx = 0,27 theoretical DEF demand for (alpha = 1) 1 ) = 1100 ml / h
1
1.05
setup with Fe-Zeolithe Fe-Zeolithe catalyst catalyst [Ø242 x (110 + 110)] 10,1 ltr
alpha alpha = 0,87 0,87 – 1.04
NOx Efficiency Efficiency with Optimize Optimized d Airless Airless Dosing Layout Layout & Strategy Strategy Summary of Sweep Test
Average Concentration
Engine parameters
With H-Cat
Without H-Cat
NH3
HNCO
NH3
HNCO
54,7
32,5
17,3
17,9
A 25 – Load Point: Exh Gas Temp: 310 310 C Exh Gas Massf.: Massf.: 850 850 kg/h kg/h °
Hydrolysis Cat Cat ( H-Cat) gives significant Advantage for NH3 formation
NH3-distribution Example 6th ICPC, ICPC, Graz, 25. - 26.04. 26.04.201 2011 1
Design w/o Hydrolysis-Cat
Design Design with Hydrolys Hydrolysis-Ca is-Catt
afte afterr 10 10 h Load Load point point A 25
afte afterr 10 10 h Load Load point point A 25
Hydr Hydr.-C .-Cat at Inlet Inlet
Hydr Hydr.-C .-Cat at outlet outlet
Cataly Catalyst st Syste System m – Valida Validatio tion n of Mixing Mixing Pipe Pipe - Deposi Deposits ts 6th ICPC, ICPC, Graz, 25. - 26.04. 26.04.201 2011 1
watercooled injector
SCR catalyst LS Technology
Liebherr SCR Production System 6th ICPC, ICPC, Graz, 25. - 26.04. 26.04.201 2011 1
hydrolysis catalyst
• Air Assisted / Airless • Mass Per Dropl plet et Size • Temperature • Layo Layout ut – Ex Exha haus ustt Gas Gas Tem Tempe pera ratu ture re ( inje inject ctor or location, insulation), Injection Strategy • Mixi Mixing ng Pipe Pipe Design Design - Tasks • Avoi oid d De Depo posi sitt fo form rmat atio ion n • Good Uniformity • Creation of NH3 • SCR Catalyst Structure • Conversion Efficiency • Ammonia Slip
Key Considerations of Urea Dosing System Design
120
160 140
100
120 80
] % [ M 60 W 40
100 90
] % [ y c n e i c i f f E n o i s r e v n o C x O N
100
] % 80 [ β β
Washcoat
60 40
20
200cpsi Standard
20
0
200/400cpsi LS
Mass Tr Transfer
0 Std
LS
Std
80 + 14%
70 60 50
i s p c 0 0 2
40 30 20
+4%
S L 0 0 4 / 0 0 2
10 0 200
2 50
3 00
3 50
Temp Te mper erat ature ure [°C]
Inf Influe luence of Cell Structur ture on NO NOx Conversion ion Effic iciiency
LS
18 [mm]
LS/PE-Foil
Flow
Position Positi on A
Position Positi on H
Concentration Tracer gas [%] 100 80 60 40 20 0
Radial Radi al Mixi Mixing ng afte afterr a subs substra trate te le leng ngth th of 18 mm LSPE LSPE Tracer racer Gas injecte injected d into a single single Channel; Channel; 200kg 200kg/h; /h; 300° 300°C
100 90 88 80
% , y c n e i c i f f E n o i s r e v n o C x O N
79 70 60 50 40 30 20 10 0 Ceramic System
Metallic System
Comp Compa ariso rison n of Cerami ramic c and Meta Metall llic ic Sys System tems: NOx-Em NOx-Emiss ission ion Reduct Reduction ion in ETC
7. FAD-Konferenz , November 2009
100
97
90
88 80
% , 70 y c n e 60 i c i f f E 50 n o i s 40 r e v n o 30 C x O 20 N
79
10 0 Ceramic System
Metallic System
Metallic System, DEF increased 20% Euro VI Development
Comp Compa ariso rison n of Cerami ramic c and Meta Metall llic ic Sys System tems: NOx-Em NOx-Emiss ission ion Reduct Reduction ion in ETC
7. FAD-Konferenz , November 2009
200 20 0 180 18 0
e u l 160 16 0 a V . 14 0 x 140 a M 12 0 ( 120 ] m 10 0 p 100 p [ , 80 p i l S - 60 3 H N 40
50
M aximum aximum Value
45
Average Average Value Valu e
40 35 30 25 20 15 10
20
5
0 Ceramic-SCR With NH3-Slip Catalyst
Metallic-SCR without NH3-Slip Catalyst
Metallic-SCR witho without ut NH3-Slip Catalyst DEF incr. 20%
e u l a V e g a r e v A ( ] m p p [ , p i l S 3 H N
0 Metallic-SCR w ith NH3-Slip Catalyst DEF increase increased d 20%
Com Compari paris son of Cerami ramic c and Metall tallic ic Syst Syste ems : NH3 Slip in ETC 7. FAD-Konferenz , November 2009
• • • •
Exhaust Emission Legislation Legislation & Strategies SCR System Layout & Development Requirements Requireme nts of Urea Dosing System – Air Assisted / Airless Conclusion
Agenda
DOC EHC Hydr.
SCR
P I L S
Silencer Silencer Silencer
Emicat ® LS
Mixer
LS
PM Metalit ®
LS/PE
High Efficient SCR System Development
LS
Vertraulich / Confidential Copying of this document and giving it to others is strictly forbidden without express authority of Em itec!
Capacity 60 l/h up to 1000 l/h
Digital Dosing Pump Urea Injection
Air-Assisted Capacity 7,5 l/h
Capac Cap acity ity 2 l/h l/h and an d 8 l/ l/h h
Capaci Cap acity ty 2 l/h l/h and an d 8 l/ l/h h
Emitec NoNOx SCR Platforms
Urea Injection
Airless Urea Injection
Airless Urea Injection
Than Thank k You You
