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Next generation SCR systemfor fuel-efficient NOx reduction
Conference Selective Catalytic Reduction 2011
26 - 28 September, 2011,Dorint Pallas Wiesbaden, Germany
Dr. Tue Johannessen
Amminex A/S
1IQPC - SCR 2011
• NO2 is already today a major problem in many European cities
• Focus on low CO2 ⇒ efficient engines.
• Efficient diesel engines ⇒ low exhaust temperature– (often below 200°C
⇒ Significant challenge for future legislative targetsand off-cycle NOx control with AdBlue®
The environmental paradox: Low CO2
- but at the expense of NOX?
IQPC - SCR 2011 2
Annual mean NO2 concentration (ug/m3) in London
Limit for 2010
US study on off-cycle performance
with urea-SCR Pick-up truck
IQPC - SCR 2011 3
0.2 g/bhp-hr
Avg. urban
engine-out
(No DEF)
Average urban
tailpipeUrban driving
– with DEF in the tank
DEF = Diesel Exhaust Fluid = North America generic name for Aqueous Urea Solution
• NOx conversion data with NH3provided by Haldor TopsøeA/S
• Test conditions:– 250 ppm NOx– Conversion measured
with 20 ppm NH3 slip– Space velocity: 63000 hr-1. – Catalyst: Fe-zeolite; aged for
50hr at 750C– NO2 content: NO2/NOx= 0.3
• Curve for AdBlue is based on the assumption that:
– AdBlue gives as high conversion as pure ammonia gas as long as injection is possible (urea hydrolysis complete)
– Steady-state AdBlue injection requires an exhaust temperature of 190-200°C(e.g. Dr. Rusch: “Urea SCR – Interaction of spray generation and exhaust system”,CTI Forum: SCR systems, Stuttgart, Oct. 08)
Ammonia-SCR: High NOx reduction potential in cold exhaust
IQPC - SCR 2011 4
0.0
0.2
0.4
0.6
0.8
1.0
150 160 170 180 190 200
NO
X c
on
vers
ion
re
lati
ve t
o 2
00
°° °°C
SCR catalyst temperature (°°°°C)
NH3-dosing: Normalized
conversion (NO2/NOx=0.3)
AdBlue (inj. at Tscr >190 °C)
Urban NOx control
with ammonia gas
Illustration of urban NOx
control potential with
liquid injection (AdBlue)
AdAmmineTM: Safe storage enables ammonia for mobile applications
IQPC - SCR 2011 5
Ammonia is very useful in many applications – incl. mobile and portable
• Storage of ammonia as
pressurized liquid
is inherently dangerous :
• AdAmmineTM: Safe storage in compacted solid
provides the safety essentially
without loss of volumetric capacity:
AdAmmine:
Usable capacity:
∼ 450g NH3 per liter AdAmmine
Ammonia release: Controlled thermal desorption
Sr(NH3)XCl2 ↔ Sr(NH3)X-1Cl2 + NH3
• Ammonia stored in an AdAmmine cartridge is about four orders of magnitude less ‘accessible’ than pressurized anhydrous ammonia.
• Even with a broken automotive cartridge/connector, passive release is very slow
– About 300 days before 1.65kg has diffused out of the broken cartridge at ambient conditions
– 3.6 liter cartridge for LD/automotive:
• Fire test shows no risk of cartridge bursting.– Plastic connector melts and causes controlled venting of ammonia. Vented ammonia is
oxidized in the flames.
How safe is it?
IQPC - SCR 2011 6
• Amminex is working jointly with OEMs primarily on two system variants
• ASDS-1: Electrical system for small/medium cars– Two smaller main cartridges pr. system
– 3.5-4.5 liter cartridges
– Control strategy for low fuel economy impact
• ASDS-2: Engine coolant system for MD/HD– Main cartridge(s) is approx. 11 liters
– Modular system concept (1-3 cartridges)
Amminex ASDS technology:Ammonia Storage and Delivery Systems
IQPC - SCR 2011 7
Key features:
• Start-up unit: Rapid dosing after cold start
• Main unit(s): System capacity
• AFM: Dosing manifold
• SW: Control of NH3-release on-demand
• Two-tank system– ∼ 11 liter cartridge (∼24 liter AdBlue)
– 4.5kg NH3 per main unit
• Start-up unit– 1.2 liter; 550W heater
• AFM (ammonia Flow Manifold)• Heating/Mounting bracket• Stand-alone ‘Box’ for easy installation• ASDS-controller + Amminex SW
• Production parts:
ASDS-2:Example of system for MD/HD
IQPC - SCR 2011 8
Ammonia dosing performance:
– Dosing turn-down ratio is at least 1/100
• Example: Min/Max: 1/100 mg NH3/s (or zero flow).
• Can be varied by control SW.
– Accuracy is at least ±5% on actual measured value in the
entire range (not ‘just’ ± 5% of max. flow).
Off-cycle NOx control during urban driving: Improved SCR performance without additional fuel penalty
IQPC - SCR 2011 9
0 500 1000 1500 2000 2500 3000 3500 4000 4500
Time [s]
0
50
100
150
200
250
Flo
w [
mg
/s],
Tem
pera
ture
[°C
], S
pee
d [
km
ph
]
SCR_avg_T [°C]
NOx_conversion [%]
Vehicle_speed [kmph]
Ammonia_dosed [mg/s]
High NOx conversion possible
with continuous “cold” exhaust
gas using Amminex solid
storage technology.
SCR Catalyst
temperature
NO
x co
nve
rsio
n /
Ca
taly
st t
em
pe
ratu
re (
°C
) /
Spe
ed
(km
/hr)
/
Am
mo
nia
do
sin
g
Required catalyst temperature for
operating AdBlue:
> 200-225°C
ASDS-1: Electrically heated system for passenger cars
IQPC - SCR 2011 10
• Start-up unit
• Main cartridge(s)
• Compact Ammonia Flow Manifold (AFM)
• Heating/mounting structure for main cartridges
• DCU with software
Example of components for automotive system
IQPC - SCR 2011 11
• Dosing of pure ammonia gas– Example of applied dosing ranges: [0-30], [0-50] mg NH3/s
– Turn-down is at least 1:100
– High dosing accuracy (e.g. ± 5% on measured value)
• Time-to-dose from cold start:– Generally in the 60-180s range
– Depends on cold soak temperature, size and heating power
• Power consumption:– Peak power: 250W
– Average power consumption: 30-70W
• Main unit storage capacity:450 g NH3 (available NH3) per liter AdAmmineTM
Key performance parameters
IQPC - SCR 2011 12
CO2-friendly control SW strategyfor ASDS-1
IQPC - SCR 2011 13
• From a vehicle integration standpoint, electrical current is simpler than coolant ‘current’
• Target: Keep power low by using the STU ‘all the time’.
• Only use electrical power for heat main unit to transfer ammonia back into the STU (regeneration).
Time (Weeks)
STU fill level
Main unit fill level
Regeneration of STU by “activation of main unit
• High accuracy and robustness
• Attractive component cost structure
• Parts from automotive suppliers
• Dosing specs:– Dynamic turn-down ratio: 1:100
(e.g. 0.3 to 30 mg NH3/s)
– Accuracy: ±5% on measured value in
entire dosing range
• Operating pressure:– Pressure: 2 bar(a) < PCartridge < 6 bar(a)
– Exhaust back-pressure: Accuracy is not sensitive to dynamic changes in exhaust back-pressure caused by engine load.
Automotive AFM design
IQPC - SCR 2011 14
On-going endurance test:
75 million valve cycles reached !
90 kg ammonia dosed
Accuracy remains at of ±5% on actual value.-5.0%
-2.5%
0.0%
2.5%
5.0%
0 10 20 30E
rro
r o
n a
ctu
al
do
sed
ma
ss (
%)
Dosing demand [mg NH3/s]
0 mill
43 mill
75 mill
Example from automotive testing of NH3-SCR
15
IQPC - SCR 2011
M. Fischer. Honda R&D Europe, Emission Control Concepts, November 2010
High conversion– even for under-floor SCR position
IQPC - SCR 2011 16
• NEDC test result with 200°C SOI temperature for Urea and
120°C for Ammonia
0
50
100
150
200
250
300
0 200 400 600 800 1000 1200
Time [s]
NOx Engine Out
NOx post SCR NH3
NOx post SCR Urea
Vehicle Speed
Tem
pera
ture
[C
]59% less NOx
Start of
injection Urea
SCRStart of
injection NH3
SCR
SOI time difference between
Urea and NH3 gasTemperature upstream SCR
Temperature downstream SCR
SCR catalyst Temperature
0
20
40
60
80
100
Phase 1 Phase 2
NO
x c
on
versi
on
[%
]
AdBlue
NH3
97
4249
10
Source: M. Fischer. Honda R&D Europe
• Exhaust interface is a steel tube – not an injector.
• No droplets – high flexibility.
• High uniformity index at different exhaust flow conditions is demonstrated(the actual interface designed by Honda not disclosed)
High uniformity, no risk of deposits, low pressure drop
IQPC - SCR 2011 17
Source: M. Fischer. Honda R&D Europe
• High uniformity with direct ammonia gas dosing
• Flexibility in SCR configuration– Close coupled
– Under-floor
– SCR-coated filter
• Flexibility in exhaust configuration– No risk of deposits
– Low pressure drop possible at ammonia inlet zone
– Significantly reduced corrosion risk (no acids intermediate of urea hydrolysis)
Benefits for exhaust system design
IQPC - SCR 2011 18
AdAmmineTM industrialization
IQPC - SCR 2011 19
• Approx. 11 liter unit.
• Material: Aluminum
• 4.5kg ammonia available for on-board usage.
• Quick-connector– Rapid exchange possible
• Approx. 500W heater (12V)
• Approx. 1.2 liter
• Quick-connector (gas)
• Electrical connector
• Other designs can be developed according to application requests.
Amminex manufacturing for MD/HD
IQPC - SCR 2011 20
The first AdAmmine plant:Nyborg, Denmark
IQPC - SCR 2011 21
Land : 45.800m2. Building: 6.424 m2 (up to 20.000 m2 allowed)
Administration, lab, cantina : 850 m2
Production: 5.600 m2
The first 10 ton of NH3 at Nyborg
IQPC - SCR 2011 22
• AdAmmineTM is not classified as hazardous goods for on-road, sea or air transportation
• European REACH:No outstanding issues
• AdAmmineTM cartridges do not have to fulfill requirements of theEuropean Pressure Directive
• Amminex has environmental approval for the Danish AdAmmineTM plant:
– 45 ton on-site ammonia storage
– Warehouse:• 10,000 HD cartridges
• 10,000 Start-up units
• Amminex HQ is ISO 9001 certified.– Production facility will be ISO and TS
certified
Applicable standards forAdAmmineTM cartridges
IQPC - SCR 2011 23
AFTERMARKET
CARTRIDGE SERVICING & REFILLING
IQPC - SCR 2011 24
• Standard production method: First-fit cartridges on new vehicles
• Cartridge replacement:Depleted cartridge is exchanged with a full unit (e.g. at OEM service station or fleet).Rapid exchange via quick-connecting (hot-swapping possible)
• Depleted cartridges can be:– Resaturated at a decentralized facility (however not directly at OEM dealer or Fleet)
– Once “exhausted”, a cartridge can be recycled completely with full utilization of raw materials.
• The AdAmmineTM “aerosol can”– For certain limited applications, the cartridge strategy may be complete recycle
because the value of the “housing” is low compared to the additional efforts of quality assuring a cartridge in a resaturation scenario.
Servicing strategy and aftermarket
IQPC - SCR 2011 25
Aftermarket: AdAmmineTM cartridges –similarities with propane distribution
IQPC - SCR 2011 26
Propane canister
(one-time use)
0.5-1kg propane
Price in retail: $2.5-3 EUR
(Including VAT)
Propane bottle
(refill)
11kg propane
Price in retail: 11-13 EUR
Propane transported in bottles:
hazardous goods (logistics “risk fee”)
Solid AdAmmineTM cartridges:
not hazardous goods
• US strategy:– Done by industrial partner
on a license basis
• Europe– Initially, refill can be done
at Amminex facility
• Amminex plant is an existing ammonia ‘hub’
• Ex. Works with 3rd party logistics company
– By industrial partner
• Other regions– To be done on a license
basis.
Refilling (resaturation)
IQPC - SCR 2011 27
Refill
Examples of AdBlue price levels
IQPC - SCR 2011 28
Cans
No of Cans Price
(£/litre)
Delivery Liter Price
(EUR/liter)
10 x 10L =
100 litres
1.60/litre Free £ 160 1001.92€
40 x 10L =
400 litres
0.85/litre Free £ 340 4001.02€
400 x 10L =
4000 litres
0.77/litre Free £ 3080 40000.92€
DrumsNo of
Drums
Price
(£/litre)
Delivery Liter Price
(EUR/liter)
2 x 210L =
420 litres
0.575/litre Free £ 241.5 4200.69€
12 x 210L =
2540 litres
0.49/litre Free £ 1244.6 25400.59€
24 x 210L =
5040 litres
0.46/litre Free £ 2318.4 50400.55€
IBCsNo of IBC's Price
(£/litre)
Delivery Liter Price
(EUR/liter)
1 x IBC =
1000 litres
0.400/litre Free £ 400 + deposit 10000.48€
5 x IBC =
5000 litres
0.379/litre Free £ 1895 + deposit 50000.45€
10 x IBC =
10000 litres
0.365/litre Free £ 3650 + deposit 100000.44€
Total Price (£ net)
Total Price (£ net)
Total Price (£ net)
Source: http://www.adblueonline.co.uk/home.php
Cans ∼∼∼∼ Cartridges
Drums ∼∼∼∼ Pallets
IBCs ∼∼∼∼ Containers
Cost level for end-users
depends on usage pattern
AdAmmineTM logistics
• There is a dialogue with Yara to use the synergy between existing NH3 plants and the establishment of cartridge recharge facilities to support development of infrastructure and for AdAmmineTM
aftermarket.
Bulk ammonia: Yara’s ammonia plants in Europe.
IQPC - SCR 2011 29
Porsgrunn
BrunsbüttelSluiskil
Le Havre
Ferrara
Tertre
• 2.4: Volume saving factor relative to liquid urea tank with same ammonia quantity
• 27: Number of pending patent families
• 9: Solid benefits: – AdAmmine™: Safe solid-state ammonia storage.
– Direct, on-demand ammonia dosing to the SCR catalyst.
– High storage capacity.
– High dosing accuracy.
– No liquid injection and no risk of deposits in the exhaust line.
– High NOx conversion – also during urban driving.
– Mechanically simple – no problems with freezing.
– Customer-friendly: No refilling – fast cartridge replacement.
– Stable NOx reductant: Very long cartridge shelf life
• 70: Current number of employees in Amminex.
• 50: Number of millions of Euro invested in Amminex A/S– 20 Million Euro invested by Faurecia in January 2011.
• 2011: Year of first AdAmmineTM plant PPAP
Summary: A few key-numbers
IQPC - SCR 2011 30