US5884475A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and device for introducing liquid into an exhaust-gas purification system
Assignee: Johnson Matthey Catalysts Germany GmbH
•
Filing: 1997-03-13
•
Granted: 1999-03-23
•
Expires: 2017-03-13
Abstract
Abstract Nitrogen oxides emitted by an internal-combustion engine operated with excess air are normally converted by the method of selective catalytic reduction by bringing the nitrogen oxides, together with ammonia, into contact with a selective catalyst. Due to the dangers associated with the use of ammonia, in a motor vehicle ammonia should only be carried in the form of a substance which liberates ammonia, generally an aqueous urea solution. A method and a device for introducing liquid into an exhaust-gas purification system according to the invention avoids frost damage to sections of the system during shutdown times and permits operation of the system at temperatures below the freezing point of the reducing agent solution being used. The method and device include a (thermally insulated) reservoir for the reducing agent liquid and a liquid supply line which is connected thereto and terminates in an outlet opening for the liquid. The reservoir and the liquid supply line can be heated. Furthermore, a heater is provided for liquefying a starting volume which is small as compared with the volume of the reservoir. The liquid supply line may also have a back-flush valve to which a gas that is under pressure can be applied. The supply line can consequently be blown free.
Inventors
- 👤 Lothar Hofmann
- 👤 Ronald Neufert
- 👤 Wieland Mathes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:33
CPC Classifications
F; F01; F01N; F01N3/00; F01N3/08; F01N3/10; F01N3/18; F01N3/20; F01N3/206; F01N3/2066; B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9404; B01D53/9409; B01D53/9431; B01D53/9495; F23; F23J; F23J15/00; F23J15/003; F01N2240/00; F01N2240/02; F01N2240/16; F01N2610/00; F01N2610/02; F01N2610/08; F01N2610/10; F01N2610/14; F01N2610/1406; F01N2610/1486; F01N2610/1493; Y; Y02; Y02A; Y02A50/00; Y02A50/20; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
64 words
A method for operating an exhaust-gas purification device, which comprises: drawing a liquid from a reservoir through a supply line; introducing the liquid into an exhaust gas in an exhaust of a combustion system during combustion, for chemical purification of the exhaust gas; and draining at least a section of the supply line with a pressurized gas during a shutdown of the combustion system.
Claim 2
Independent Claim
64 words
A method for operating an exhaust-gas purification device, which comprises: drawing a liquid from a reservoir through a supply line; introducing the liquid into an exhaust gas in an exhaust of a combustion system during combustion, for chemical purification of the exhaust gas; and draining at least a section of the supply line with a pressurized gas during a shutdown of the combustion system.
Claim 3
Dependent Claim
70 words
The method according to claim 1, which comprises feeding the pressurized gas through a pressurized-gas inlet and a valve into the supply line between the reservoir and the exhaust of the combustion system, for draining a part of the supply line between the pressurized-gas inlet and the reservoir into the reservoir, and for draining a part of the supply line between the pressurized-gas inlet and the exhaust into the exhaust.
Claim 4
Dependent Claim
32 words
The method according to claim 1, which comprises introducing an aqueous urea solution as the liquid into the exhaust gas of an internal-combustion engine of a motor vehicle as the combustion system.
Claim 5
Dependent Claim
18 words
The method according to claim 3, which comprises operating the internal-combustion engine operated with an excess of air.
Claim 6
Independent Claim
82 words
A method of operating an exhaust-gas purification device, which comprises: drawing a liquid through a supply line from a reservoir having a given volume; introducing the liquid into an exhaust gas in an exhaust of a combustion system during combustion, for chemical purification of the exhaust gas; and heating a starting volume of the liquid being smaller than the given volume with a heater and introducing the starting volume into the exhaust gas, no later than during startup of the combustion system.
Claim 7
Independent Claim
82 words
A method of operating an exhaust-gas purification device, which comprises: drawing a liquid through a supply line from a reservoir having a given volume; introducing the liquid into an exhaust gas in an exhaust of a combustion system during combustion, for chemical purification of the exhaust gas; and heating a starting volume of the liquid being smaller than the given volume with a heater and introducing the starting volume into the exhaust gas, no later than during startup of the combustion system.
Claim 8
Dependent Claim
19 words
The method according to claim 5, which comprises storing the starting volume of the liquid in a further container.
Claim 9
Dependent Claim
32 words
The method according to claim 3, which comprises introducing an aqueous urea solution as the liquid into the exhaust gas of an internal-combustion engine of a motor vehicle as the combustion system.
Claim 10
Dependent Claim
17 words
The,method according to claim 7, which comprises operating the internal-combustion engine operated with an excess of air.
Claim 11
Independent Claim
55 words
A device for operating an exhaust-gas purification device, comprising: a reservoir for a liquid; a supply line connected between said reservoir and an exhaust-gas purification device; a pressurized-gas inlet; and a valve connected between said pressurized-gas inlet and said supply line for introducing pressurized gas into said supply line in a direction towards said reservoir.
Claim 12
Independent Claim
55 words
A device for operating an exhaust-gas purification device, comprising: a reservoir for a liquid; a supply line connected between said reservoir and an exhaust-gas purification device; a pressurized-gas inlet; and a valve connected between said pressurized-gas inlet and said supply line for introducing pressurized gas into said supply line in a direction towards said reservoir.
Claim 13
Dependent Claim
18 words
The device according to claim 9, wherein said valve is a back-flush valve disposed in said supply line.
Claim 14
Dependent Claim
23 words
The device according to claim 10, including further back-flushable structural components disposed in said liquid supply line between said valve and said reservoir.
Claim 15
Dependent Claim
46 words
The device according to claim 9, wherein said valve has a first state permitting a flow through said supply line from said reservoir to the exhaust-gas purification device and a second state permitting a flow through said supply line from said pressurized-gas inlet to said reservoir.
Claim 16
Dependent Claim
19 words
The device according to claim 12, wherein said valve has a third state in which said reservoir is closed.
Claim 17
Dependent Claim
25 words
The device according to claim 12, wherein said valve configuration has a state in which said pressurized-gas inlet is connected to the exhaust-gas purification device.
Claim 18
Dependent Claim
25 words
The device according to claim 13, wherein said valve configuration has a state in which said pressurized-gas inlet is connected to the exhaust-gas purification device.
Claim 19
Dependent Claim
25 words
The device according to claim 9, wherein the pressurized gas is introduced into said supply line at a location immediately alongside the exhaust-gas purification device.
Claim 20
Dependent Claim
29 words
The device according to claim 9, wherein the pressurized gas is introduced into said supply line at a location nearer to the exhaust-gas purification device than to said reservoir.
Claim 21
Dependent Claim
15 words
The device according to claim 9, including a device for heating said liquid supply line.
Claim 22
Dependent Claim
36 words
The device according to claim 18, wherein said reservoir has a given volume, and including an intermediate container associated with said heatable liquid supply line for a volume of the liquid smaller than said given volume.
Claim 23
Dependent Claim
30 words
The device according to claim 9, wherein said reservoir has a given volume, and including a heater for liquefying a starting volume of the liquid smaller than said given volume.
Claim 24
Dependent Claim
17 words
The device according to claim 20, wherein said heater for the starting volume is ad electrical heater.
Claim 25
Dependent Claim
21 words
The device according to claim 20, wherein said reservoir is a tank, and including an intermediate container accommodating the starting volume.
Claim 26
Dependent Claim
24 words
The device according to claim 22, including a device for heating at least said tank and said supply line with a liquid heating medium.
Claim 27
Dependent Claim
15 words
The device according to claim 20, including a device for heating said supply line electrically.
Claim 28
Dependent Claim
23 words
The device according to claim 20, including a device associated with said reservoir for at least one of temperature monitoring and temperature control.
Claim 29
Dependent Claim
62 words
An exhaust-gas purification system of a utility motor vehicle having an internal-combustion engine, the system comprising: a reservoir for a liquid; a supply line connected between said reservoir and an exhaust-gas purification device; a pressurized-gas inlet; and a valve connected between said pressurized-gas inlet and said supply line for introducing pressurized gas into said supply line in a direction towards said reservoir.
Claim 30
Dependent Claim
62 words
An exhaust-gas purification system of a utility motor vehicle having an internal-combustion engine, the system comprising: a reservoir for a liquid; a supply line connected between said reservoir and an exhaust-gas purification device; a pressurized-gas inlet; and a valve connected between said pressurized-gas inlet and said supply line for introducing pressurized gas into said supply line in a direction towards said reservoir.
Claim 31
Dependent Claim
17 words
The system according to claim 26, wherein the internal-combustion engine is operated with an excess of air.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-03-22 | 2002-09-21 | 2003-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-03-22 | 2006-09-21 | 2007-03-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-03-22 | 2010-09-21 | 2011-03-23 | $7700.00 | Window Closed / Lapsed |