Exhaust Treatment System Having Metal Hydride Module

Abstract

An exhaust after-treatment system for treating an exhaust produced by an engine. The exhaust after-treatment system includes an exhaust passage, a catalytic exhaust after-treatment component in communication with the exhaust passage for treating the exhaust, and a metal hydride module in communication with the exhaust passage that receives a portion of the exhaust therein at a location positioned upstream from the catalytic exhaust after-treatment component. The portion of the exhaust that enters the metal hydride module reacts with a metal hydride contained in the metal hydride module to produce hydrogen gas that facilitates the treating of the exhaust by the catalytic exhaust after-treatment component.

What is claimed is: 
     
         1 . An exhaust after-treatment system for treating an exhaust produced by an engine, the exhaust after-treatment system comprising:
 an exhaust passage;   at least one catalytic exhaust after-treatment component in communication with the exhaust passage for treating the exhaust; and   a metal hydride module in communication with the exhaust passage that receives a portion of the exhaust therein at a location positioned upstream from the catalytic exhaust after-treatment component,   wherein the portion of the exhaust that enters the metal hydride module reacts with a metal hydride contained in the metal hydride module to produce hydrogen gas that facilitates the treating of the exhaust by the catalytic exhaust after-treatment component.   
     
     
         2 . The exhaust after-treatment system according to  claim 1 , wherein the catalytic exhaust after-treatment component is a diesel particulate filter, a gasoline particulate filter, a SCR exhaust treatment component, a NOx storage catalyst component, a hydrocarbon storage catalyst component, a LNC exhaust treatment component, a diesel oxidation catalyst component, a methane oxidation catalyst component, a three-way catalyst component, an ammonia slip catalyst component, or a combination thereof. 
     
     
         3 . The exhaust after-treatment system according to  claim 2 , wherein the catalytic exhaust after-treatment component is the LNC exhaust treatment component. 
     
     
         4 . The exhaust after-treatment system according to  claim 1 , wherein the metal hydride module is mounted entirely within the exhaust passage. 
     
     
         5 . The exhaust after-treatment system according to  claim 1 , further comprising a bypass passage in communication with the exhaust passage that receives the portion of the exhaust, the metal hydride module being positioned within bypass passage. 
     
     
         6 . The exhaust after-treatment system according to  claim 1 , wherein the metal hydride module includes a valve configured to allow entry of the portion of the exhaust into the metal hydride module. 
     
     
         7 . The exhaust after-treatment system according to  claim 6 , further comprising a controller in communication with the valve that is configured to open and close the valve. 
     
     
         8 . The exhaust after-treatment system according to  claim 1 , further comprising a mixing device configured to intermix the hydrogen gas and the exhaust, the mixing device being positioned in the exhaust passage between the metal hydride module and the catalyst exhaust treatment component. 
     
     
         9 . The exhaust after-treatment system according to  claim 1 , further comprising an injector for dosing an exhaust treatment fluid into the exhaust passage. 
     
     
         10 . The exhaust after-treatment system according to  claim 9 , wherein the exhaust treatment fluid is a hydrocarbon exhaust treatment fluid or an exhaust treatment fluid comprising urea. 
     
     
         11 . The exhaust after-treatment system according to  claim 10 , wherein the hydrocarbon exhaust treatment fluid is ethanol, an ethanol-gasoline mixture, or an ultra-low sulfur diesel fuel. 
     
     
         12 . The exhaust after-treatment system according to  claim 1 , wherein the metal hydride module includes a relief valve. 
     
     
         13 . The exhaust after-treatment system according to  claim 1 , wherein the metal hydride contains at least one component selected from the group consisting of an alkali metal hydride component, an alkaline earth metal hydride components, and combinations thereof. 
     
     
         14 . An engine exhaust after-treatment system for treating an exhaust produced by the engine, the after-treatment system comprising:
 an exhaust passage including at least one exhaust treatment component therein;   a bypass passage including an inlet that receives a portion of the exhaust from the exhaust passage, a metal hydride module downstream from the inlet, and an outlet downstream from the metal hydride module that returns the portion of the exhaust to the exhaust passage;   a metal hydride material within the metal hydride module configured to react with the exhaust and produce a hydrogen gas that is returned to the exhaust passage along with the portion of the exhaust;   a valve positioned at the inlet of the bypass passage configured to allow and prevent flow of the portion of the exhaust into the bypass passage; and   a controller in communication with the valve, the controller configured to open and close the valve; and   a sensor in communication with the controller, the sensor configured to send a signal indicative of an operating condition of the exhaust after-treatment system,   wherein based on the signal indicative of the operating condition, the controller opens and closes the valve to control generation of the hydrogen gas by the metal hydride material.   
     
     
         15 . The exhaust after-treatment system according to  claim 14 , wherein the catalytic exhaust after-treatment component is a diesel particulate filter, a gasoline particulate filter, a SCR exhaust treatment component, a NOx storage catalyst component, a hydrocarbon storage catalyst component, a LNC exhaust treatment component, a diesel oxidation catalyst component, a methane oxidation catalyst component, a three-way catalyst component, an ammonia slip catalyst component, or a combination thereof. 
     
     
         16 . The exhaust after-treatment system according to  claim 15 , wherein the catalytic exhaust after-treatment component is the LNC exhaust treatment component. 
     
     
         17 . The exhaust after-treatment system according to  claim 14 , further comprising a mixing device configured to intermix the hydrogen gas and the exhaust, the mixing device being positioned in the exhaust passage between the metal hydride module and the catalyst exhaust treatment component. 
     
     
         18 . The exhaust after-treatment system according to  claim 14 , further comprising an injector for dosing an exhaust treatment fluid into the exhaust passage. 
     
     
         19 . The exhaust after-treatment system according to  claim 18 , wherein the exhaust treatment fluid is a hydrocarbon exhaust treatment fluid or an exhaust treatment fluid comprising urea. 
     
     
         20 . The exhaust after-treatment system according to  claim 19 , wherein the hydrocarbon exhaust treatment fluid is ethanol, an ethanol-gasoline mixture, or an ultra-low sulfur diesel fuel. 
     
     
         21 . The exhaust after-treatment system according to  claim 14 , wherein the metal hydride module includes a relief valve. 
     
     
         22 . The exhaust after-treatment system according to  claim 14 , wherein the metal hydride material contains at least one component selected from the group consisting of an alkali metal hydride component, an alkaline earth metal hydride component, and combinations thereof.