Method and system for improving the robustness of aftertreatment systems

Abstract

A method for treating a catalyst in an internal combustion engine is disclosed. The method comprises detecting the efficiency of a catalyst; sending the catalyst efficiency to a threshold monitor; and heating the catalyst when the detected catalyst efficiency is below a predetermined percentage.

What is claimed is: 
     
         1 . A method of treating a catalyst in an internal combustion engine comprising:
 detecting efficiency of a catalyst;   sending the catalyst efficiency to a threshold monitor; and   heating the catalyst when the detected catalyst efficiency is below a predetermined percentage.   
     
     
         2 . The method of  claim 1  comprising detecting the efficiency of the catalyst based on the threshold monitor. 
     
     
         3 . The method of  claim 1  wherein the catalyst comprises a copper-zeolite based catalyst. 
     
     
         4 . The method of  claim 2  wherein the threshold monitor comprises a sulphur estimator. 
     
     
         5 . The method of  claim 2  wherein the threshold monitor comprises a catalyst efficiency monitor. 
     
     
         6 . The method of  claim 2  wherein the threshold monitor comprises a timing device. 
     
     
         7 . The method of  claim 2  wherein the threshold monitor comprises a humidity monitor. 
     
     
         8 . The method of  claim 1  wherein heating the catalyst in response to the predetermined percentage further comprises regenerating the catalyst by applying a high temperature treatment. 
     
     
         9 . The method of  claim 7  wherein regenerating the catalyst by a high temperature treatment further comprises temperatures of at least 650° C. 
     
     
         10 . The method of  claim 8  wherein the high temperature treatment increases the oxidation functionality of the catalyst. 
     
     
         11 . The method of  claim 1  wherein heating the catalyst in response to the predetermined percentage comprises a thermal event. 
     
     
         12 . The method of  claim 6  wherein the thermal event comprises a system deSO x  which removes sulphur from the internal combustion engine. 
     
     
         13 . The method of  claim 6  wherein the thermal event comprises a system desorb which removes unburned hydrocarbons from the internal combustion engine. 
     
     
         14 . A system for treating a catalyst in an internal combustion engine comprising:
 a diesel exhaust fluid valve; and   a plurality of threshold monitors for initiating a catalyst regeneration.   
     
     
         15 . The system of  claim 14  further comprising a diesel particulate filter (DPF). 
     
     
         16 . The system of  claim 14  wherein the catalyst comprises a DOC, SCR, or AMO x  catalyst. 
     
     
         17 . The system of  claim 14  wherein the threshold monitors comprise a timing device, a sulphur estimator, a catalyst efficiency monitor, or a humidity monitor. 
     
     
         18 . The system of  claim 14  wherein the catalyst regeneration comprises heating the system to a temperature of at least 200° C. 
     
     
         19 . An engine system comprising:
 an engine; and   a catalyst system coupled to the engine; wherein the catalyst system comprises a catalyst; a diesel exhaust fluid valve; and a plurality of threshold monitors for initiating a catalyst regeneration.   
     
     
         20 . The engine system of  claim 19  further comprising a diesel particulate filter (DPF).