Diagnostic system for monitoring catalyst performance
First Claim
Patent Images
1. A method for monitoring catalyst performance, comprising:
- introducing an exhaust gas stream into an exhaust system that includes a plurality of treatment devices and a plurality of gas sensors disposed in fluid communication with said plurality of treatment devices, wherein said plurality of treatment devices comprises a first treatment device, a second treatment device, and a third treatment device, and said plurality of gas sensors comprise a first gas sensor disposed before said first treatment device, a second gas sensor disposed between said second treatment device and said third treatment device, and a third gas sensor disposed after said third treatment device, and further wherein at least two treatment devices comprise a nitrogen oxides adsorber material;
monitoring said exhaust gas stream using said plurality of gas sensors;
passing said exhaust gas stream through said plurality of treatment devices;
measuring a first response time differential between said first gas sensor and said second gas sensor, and a second response time between said first gas sensor and said third gas sensor;
calculating a sulfur contamination index based on said response time differentials between said plurality of gas sensors; and
desulfating said treatment devices based upon said first response time, said second response time, and said sulfur contamination index and adjusting an air to fuel ratio to regenerate a catalyst material of one or more of said treatment devices.
0 Assignments
0 Petitions
Accused Products
Abstract
A diagnostic system for monitoring catalyst performance in an exhaust system comprises a plurality of treatment devices catalytically treating an exhaust gas stream, and a plurality of gas sensors for monitoring the catalyst performance of the treatment devices to determine when sulfur poisoning occurs. An on-board diagnostic system receives signals from the gas sensors, and, based upon response time differentials between sensors, determines whether the treatment devices are experiencing sulfur poisoning.
29 Citations
8 Claims
-
1. A method for monitoring catalyst performance, comprising:
-
introducing an exhaust gas stream into an exhaust system that includes a plurality of treatment devices and a plurality of gas sensors disposed in fluid communication with said plurality of treatment devices, wherein said plurality of treatment devices comprises a first treatment device, a second treatment device, and a third treatment device, and said plurality of gas sensors comprise a first gas sensor disposed before said first treatment device, a second gas sensor disposed between said second treatment device and said third treatment device, and a third gas sensor disposed after said third treatment device, and further wherein at least two treatment devices comprise a nitrogen oxides adsorber material; monitoring said exhaust gas stream using said plurality of gas sensors; passing said exhaust gas stream through said plurality of treatment devices; measuring a first response time differential between said first gas sensor and said second gas sensor, and a second response time between said first gas sensor and said third gas sensor; calculating a sulfur contamination index based on said response time differentials between said plurality of gas sensors; and desulfating said treatment devices based upon said first response time, said second response time, and said sulfur contamination index and adjusting an air to fuel ratio to regenerate a catalyst material of one or more of said treatment devices. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A catalyst performance diagnostics system, comprising:
-
a plurality of treatment devices, wherein said plurality comprises a first treatment device, a second treatment device, and a third treatment device; a plurality of sensors disposed in fluid communication with said plurality of treatment devices, wherein said plurality of sensors comprise a first stoichiometric switch sensor disposed before said first treatment device, a second stoichiometric switch sensor disposed between said second treatment device and said third treatment device, and a third NOx sensor disposed after said third treatment device; and an on-board diagnostic system coupled to said plurality of sensors.
-
Specification