Method and apparatus for monitoring ash accumulation in a particulate filter of an emission abatement assembly

• US 20050150214A1
• Filed: 08/31/2004
• Published: 07/14/2005
• Est. Priority Date: 01/13/2004
• Status: Active Grant

• Current Assignee: ET US Holdings LLC
• Original Assignee: ET US Holdings LLC
• Inventors: Johnson, Randall J., Crawley, Wilbur H.
• Granted Patent: US 7,581,389 B2
• Time in Patent Office: Days
• US Class Current: 60/295
• CPC Class Codes: F01N 11/002 the diagnostic devices measuring or estimating temperature or pressure in, or downstream of the exhaust apparatus
• CPC Class Codes: F01N 2240/14 a fuel burner
• CPC Class Codes: F01N 2550/04 Filtering activity of particulate filters
• CPC Class Codes: F01N 2900/1406 Exhaust gas pressure
• CPC Class Codes: F01N 2900/1606 Particle filter loading or soot amount
• CPC Class Codes: F01N 2900/1611 Particle filter ash amount
• CPC Class Codes: F01N 3/025 using fuel burner or by adding fuel to exhaust
• CPC Class Codes: F01N 9/002 of filter regeneration, e.g. detection of clogging
• CPC Class Codes: F23Q 3/008 Structurally associated with fluid-fuel burners
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A method of monitoring ash buildup in a particulate filter includes determining particulate accumulation in the filters subsequent to filter regeneration to determine when the filter is in need of servicing to remove ash therefrom. An emission abatement assembly is also disclosed.

Claims

1. A method of monitoring ash buildup in a particulate filter of an emission abatement assembly, the method comprising the steps of:

regenerating the particulate filter to remove soot accumulated therein,

generating a control signal subsequent to the regenerating step, and

determining a level of ash accumulation in the particulate filter in response to generation of the control signal.

2. The method of claim 1, further comprising the step of generating an error signal if the level of ash accumulation in the particulate filter exceeds a predetermined limit.

3. The method of claim 2, further comprising the step of communicating the error signal to an engine control unit of an engine.

4. The method of claim 1, wherein the determining step comprises determining a pressure drop across the particulate filter.

5. The method of claim 4, further comprising the step of generating an error signal if the pressure drop across the particulate filter exceeds a predetermined limit.

6. The method of claim 5, further comprising the step of communicating the error signal to an engine control unit of an engine.

7. The method of claim 1, wherein the determining step comprises monitoring output from a pressure sensor.

8. An emission abatement assembly, comprising:

a particulate filter,

a fuel-fired burner positioned upstream of the particulate filter,

a sensor configured to sense the accumulation level of particulate matter within the particulate filter, and

a controller electrically coupled to the sensor, the controller comprising (i) a processor, and (ii) a memory device electrically coupled to the processor, the memory device having stored therein a plurality of instructions which, when executed by the processor, cause the processor to;

operate the fuel-fired burner to regenerate the particulate filter to remove soot accumulated therein,

generate a control signal subsequent to operation of the fuel-fired burner, and

monitor output from the sensor to determine a level of ash accumulation in the particulate filter in response to generation of the control signal.

9. The emission abatement assembly of claim 8, wherein the plurality of instructions, when executed by the processor, further cause the processor to generate an error signal if the level of ash accumulation in the particulate filter exceeds a predetermined limit.

10. The emission abatement assembly of claim 9, wherein the plurality of instructions, when executed by the processor, further cause the processor to communicate the error signal to an engine control unit of an engine.

11. The emission abatement assembly of claim 8, wherein:

the sensor comprises a pair of pressure sensors, and

the plurality of instructions, when executed by the processor, further cause the processor to monitor output from the pair of pressure sensors to determine a pressure drop across the particulate filter.

12. The emission abatement assembly of claim 11, wherein the plurality of instructions, when executed by the processor, further cause the processor to generate an error signal if the pressure drop across the particulate filter exceeds a predetermined limit.

13. The emission abatement assembly of claim 12, wherein the plurality of instructions, when executed by the processor, further cause the processor to communicate the error signal to an engine control unit of an engine.

14. A method of monitoring ash buildup in a particulate filter of an emission abatement assembly, the method comprising the steps of:

determining the end of a regeneration cycle of the particulate filter and generating a control signal in response thereto, and

determining a level of particulate accumulation in the particulate filter in response to generation of the control signal.

15. The method of claim 14, wherein:

the emission abatement assembly comprises a fuel-fired burner operable to generate heat which oxidizes soot trapped in the particulate filter, and

the step of determining the end of a regeneration cycle comprises determining when fuel ceases to be supplied to the fuel-fired burner.

16. The method of claim 14, wherein the step of determining the level of particulate accumulation in the particulate filter comprises determining a pressure drop across the particulate filter.

17. The method of claim 14, further comprising the step of generating an error signal if the level of particulate accumulation in the particulate filter exceeds a predetermined limit.

18. The method of claim 17, further comprising the step of communicating the error signal to an engine control unit of an engine.