Regeneration Method For Ceramic Honeycomb Structures

Abstract

A method for regenerating a diesel particulate filter includes elevating a temperature of a gas stream flowing into an inlet of the diesel particulate filter to greater than or equal to 450° of the inlet of the diesel particulate filter, wherein the gas stream at the inlet of the diesel particulate filter contains an amount of NOx of equal to or greater than 300 ppm, and an amount of O 2 of equal to or greater than 5% volume, thereby burning the soot within the diesel particulate filter. The method also includes elevating a temperature of the gas stream flowing into the inlet of the diesel particulate filter to less than or equal to 550° C. at the inlet of the diesel particulate filter, wherein a burn rate of soot from porous walls of the diesel particulate filter is greater than or equal to 3.8 grams/liter/hour.

1 - 28 . (canceled) 
     
     
         29 . A method for at least partially regenerating a diesel particulate filter, wherein the diesel particulate filter comprises an inlet, an outlet, and a porous body comprising a plurality of porous walls disposed between the inlet and the outlet, wherein a gas stream flows into the inlet, through the diesel particulate filter, and out of the outlet, and wherein the porous walls contain an amount of carbon soot trapped in or on the porous walls, the method comprising:
 elevating a temperature of the gas stream flowing into the inlet of the diesel particulate filter to greater than or equal to 450° C. at the inlet of the diesel particulate filter;   wherein the gas stream at the inlet of the diesel particulate filter contains an amount of NOx of equal to or greater than 500 ppm, and an amount of O 2  of equal to or greater than 5% vol., thereby burning the soot in the diesel particulate filter.   
     
     
         30 . The method of  claim 29 , wherein the temperature of the gas stream at the inlet of the diesel particulate filter is between 450° C. and 600° C. 
     
     
         31 . The method of  claim 29 , wherein the temperature of the gas stream at the inlet of the diesel particulate filter is between 450° C. and 575° C. 
     
     
         32 . The method of  claim 31 , wherein the temperature of the gas stream at the inlet of the diesel particulate filter between 450° C. and 550° C. 
     
     
         33 . The method of  claim 32 , wherein the gas stream at the inlet of the diesel particulate filter contains an amount of NOx of greater than or equal to 750 ppm. 
     
     
         34 . The method of  claim 29 , wherein the gas stream at the inlet of the diesel particulate filter contains an amount of O 2  of equal to or greater than 7% vol. 
     
     
         35 . The method of  claim 29 , wherein a burn rate of the soot from the porous walls is greater than or equal to 3.8 grams/liter/hour. 
     
     
         36 . The method of  claim 29 , wherein the temperature of the gas stream is greater than or equal to 500° C. at the inlet of the diesel particulate filter, and the amount of NOx is greater than or equal to 750 ppm at the inlet of the diesel particulate filter. 
     
     
         37 . The method of  claim 29 , wherein the temperature of the gas stream at the inlet of the diesel particulate filter is between 450° C. and 600° C., and the gas stream downstream of the diesel particulate filter is treated via selective catalytic reduction sufficient to remove at least 50% of the NOx from the gas stream. 
     
     
         38 . The method of  claim 29 , wherein the burn rate is maintained at least until the amount of the soot trapped in or on the porous walls is less than or equal to 6 grams/liter. 
     
     
         39 . A method for at least partially regenerating a diesel particulate filter, wherein the diesel particulate filter comprises an inlet, an outlet, and a porous body comprising a plurality of porous walls disposed between the inlet and the outlet, wherein a gas stream flows into the inlet, through the diesel particulate filter, and out of the outlet, and wherein the porous walls contain an amount of carbon soot trapped in or on the porous walls, the method comprising:
 elevating a temperature of the gas stream flowing into the inlet of the diesel particulate filter to greater than or equal to 450° C. at the inlet of the diesel particulate filter;   wherein the gas stream at the inlet of the diesel particulate filter contains an amount of NOx of equal to or greater than 300 ppm, and an amount of O 2  of equal to or greater than 5% vol., thereby burning the soot in the diesel particulate filter and wherein the gas stream downstream of the diesel particulate filter is treated via selective catalytic reduction.   
     
     
         40 . The method of  claim 39 , wherein the selective catalytic reduction occurs in an SCR device, and wherein the temperature of the gas stream entering the SCR device is between 500 and 600° C. 
     
     
         41 . The method of  claim 40 , wherein the selective catalytic reduction has an ammonia conversion of greater than 95%. 
     
     
         42 . The method of  claim 39 , wherein the gas stream at the inlet of the diesel particulate filter contains an amount of O 2  of equal to or greater than 7% vol. 
     
     
         43 . The method of  claim 39 , wherein the gas stream at the inlet of the diesel particulate filter contains an amount of NOx of equal to or greater than 500 ppm. 
     
     
         44 . The method of  claim 39 , wherein a burn rate of the soot from the porous walls is greater than or equal to 3.8 grams/liter/hour. 
     
     
         45 . The method of  claim 39 , wherein the temperature of the gas stream is greater than or equal to 500° C. at the inlet of the diesel particulate filter, and the amount of NOx is greater than or equal to 750 ppm at the inlet of the diesel particulate filter. 
     
     
         46 . The method of  claim 39 , wherein the temperature of the gas stream at the inlet of the diesel particulate filter is between 450° C. and 600° C., and the selective catalytic reduction is sufficient to remove at least 50% of the NOx from the gas stream. 
     
     
         47 . The method of  claim 39 , wherein the burn rate is maintained at least until the amount of the soot trapped in or on the porous walls is less than or equal to 6 grams/liter.