Patent US6928806B2 successfully refreshed from Google Patents.
US6928806B2
Expired / Lapsed
US
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Exhaust gas aftertreatment systems
Assignee: Ford Motor Co
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Filing: 2002-11-21
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Granted: 2005-08-16
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Expires: 2022-11-21
Abstract
Abstract A system for effective NOx and particulate matter control in a diesel or other lean burn internal combustion engine is presented. The system includes a urea-based SCR catalyst having an oxidation catalyst coupled upstream of it and a particulate filter coupled downstream of the SCR catalyst. This system configuration results in improved NOx conversion due to fast SCR catalyst warm-up and higher operating temperatures. Additionally, placing the particulate filter last in this system configuration reduces tailpipe ammonia emissions as well as prevents any thermal damage to the SCR catalyst due to the particulate filter regeneration.
Inventors
- 👤 Paul Joseph Tennison
- 👤 Paul M. Laing
- 👤 Christine Kay Lambert
- 👤 Robert Henry Hammerle
- 👤 William Charles Ruona
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:20
CPC Classifications
F; F01; F01N; F01N3/00; F01N3/02; F01N3/021; F01N3/033; F01N3/035; B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9404; B01D53/9409; B01D53/9431; B01D53/9495; F01N13/00; F01N13/009; F01N13/0093; F01N3/023; F01N3/025; F01N3/0253; F01N3/08; F01N3/10; F01N3/18; F01N3/20; F01N3/206; F01N3/2066; F01N2240/00; F01N2240/16; F01N2570/00; F01N2570/12; F01N2570/14; F01N2610/00; F01N2610/02; F01N2610/03; F01N2610/08; F01N2610/10; F02; F02D; F02D41/00; F02D41/02; F02D41/14; F02D41/1438; F02D41/1473; F02D41/1475; Y; Y02; Y02A; Y02A50/00; Y02A50/20; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
61 words
An exhaust gas aftertreatment system for an internal combustion engine exhaust, the system comprising: a first oxidation catalyst; a selective catalytic reduction (SCR) catalyst coupled downstream of said first oxidation catalyst; and a particulate filter coupled downstream of said SCR catalyst; and a reductant delivery system coupled to an exhaust gas manifold between said first oxidation catalyst and said SCR catalyst.
Claim 2
Dependent Claim
61 words
An exhaust gas aftertreatment system for an internal combustion engine exhaust, the system comprising: a first oxidation catalyst; a selective catalytic reduction (SCR) catalyst coupled downstream of said first oxidation catalyst; and a particulate filter coupled downstream of said SCR catalyst; and a reductant delivery system coupled to an exhaust gas manifold between said first oxidation catalyst and said SCR catalyst.
Claim 3
Dependent Claim
23 words
The system as set forth in claim 1 further comprising a second oxidation catalyst coupled between said SCR catalyst and said particulate filter.
Claim 4
Dependent Claim
20 words
The system as set forth in claim 1 wherein a second oxidation catalyst is washcoated onto said particulate filter inlet.
Claim 5
Dependent Claim
23 words
The system as set forth in claim 1 further comprising an ammonia clean-up catalyst coupled between said SCR catalyst and said particulate filter.
Claim 6
Dependent Claim
15 words
The system as set forth in claim 1 wherein the engine is a diesel engine.
Claim 7
Dependent Claim
20 words
The system as set forth in claim 1 further comprising a first NOx sensor coupled downstream of said SCR catalyst.
Claim 8
Dependent Claim
20 words
The system as set forth in claim 6 further comprising a second NOx sensor coupled upstream of said SCR catalyst.
Claim 9
Dependent Claim
22 words
The system as set forth in claim 1 wherein said particulate filter is a catalyzed particulate filter having a precious metal washcoat.
Claim 10
Dependent Claim
17 words
The system as set forth in claim 8 wherein said precious metal washcoat is a platinum washcoat.
Claim 11
Dependent Claim
19 words
The system as set forth in claim 1 wherein said reductant delivery system includes at least a heating element.
Claim 12
Dependent Claim
30 words
The system as set forth in claim 10 wherein said reductant delivery system injects a vaporized mixture of reductant and air into an exhaust gas stream entering said SCR catalyst.
Claim 13
Dependent Claim
14 words
The system as set forth in claim 11 wherein said reductant is aqueous urea.
Claim 14
Dependent Claim
21 words
The system as set forth in claim 1 further comprising a reductant delivery system coupled upstream of said first oxidation catalyst.
Claim 15
Dependent Claim
19 words
The system as set forth in claim 13 wherein said reductant delivery system includes at least a heating element.
Claim 16
Dependent Claim
31 words
The system as set forth in claim 14 wherein said reductant delivery system injects a vaporized mixture of hydrocarbon and air into an exhaust gas stream entering said first oxidation catalyst.
Claim 17
Dependent Claim
28 words
The system as set forth in claim 1 further comprising a reductant delivery system coupled to an exhaust gas manifold between said SCR catalyst and said particulate filter.
Claim 18
Dependent Claim
19 words
The system as set forth in claim 16 wherein said reductant delivery system includes at least a heating element.
Claim 19
Dependent Claim
30 words
The system as set forth in claim 17 wherein said reductant delivery system injects a vaporized mixture of hydrocarbon and air into an exhaust gas stream entering said particulate filter.
Claim 20
Dependent Claim
31 words
The system as set forth in claim 1 further comprising a controller for adjusting an amount of a reductant supplied to said reductant delivery system based on an engine operating parameter.
Claim 21
Dependent Claim
17 words
The system as set forth in claim 19 wherein said engine operating parameter is a pedal position.
Claim 22
Dependent Claim
18 words
The system as set forth in claim 20 wherein said engine operating parameter is an SCR catalyst temperature.
Claim 23
Dependent Claim
28 words
The system as set forth in claim 20 wherein said engine operating parameter is an amount of NOx in an exhaust gas mixture downstream of said SCR catalyst.
Claim 24
Dependent Claim
86 words
An exhaust gas aftertreatment system for an internal combustion engine exhaust, the system comprising: a first oxidation catalyst; a selective catalytic reduction (SCR) catalyst coupled downstream of said first oxidation catalyst; a particulate filter coupled downstream of said SCR catalyst, where said particulate filter is a catalyzed particulate filter having a platinum washcoat; a first reductant delivery system coupled to an exhaust gas manifold between said first oxidation catalyst and said SCR catalyst; and a second reductant delivery system coupled immediately upstream of said particulate filter.
Claim 25
Dependent Claim
86 words
An exhaust gas aftertreatment system for an internal combustion engine exhaust, the system comprising: a first oxidation catalyst; a selective catalytic reduction (SCR) catalyst coupled downstream of said first oxidation catalyst; a particulate filter coupled downstream of said SCR catalyst, where said particulate filter is a catalyzed particulate filter having a platinum washcoat; a first reductant delivery system coupled to an exhaust gas manifold between said first oxidation catalyst and said SCR catalyst; and a second reductant delivery system coupled immediately upstream of said particulate filter.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2008-08-15 | 2009-02-14 | 2009-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2012-08-15 | 2013-02-14 | 2013-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2016-08-15 | 2017-02-14 | 2017-08-16 | $7700.00 | Window Closed / Lapsed |