Method For Regeneration Of An Exhaust Aftertreatment System

Abstract

In a method and a device for regeneration of a regeneratable unit which forms part of an exhaust aftertreatment system, the unit is arranged upstream of a catalytic rector in an exhaust duct connected to an internal combustion engine. Part of the inlet air of the internal combustion engine is during regeneration conducted to the exhaust duct for regulating the temperature in the gas flow to the catalytic reactor.

1 . A method for regeneration of a regeneratable unit which forms part of an exhaust aftertreatment system and is arranged upstream of a catalytic reactor in an exhaust duct connected to an internal combustion engine, comprising conducting part of inlet air of the internal combustion engine during regeneration to the exhaust duct for regulating temperature in a gas flow to the catalytic reactor. 
   
   
       2 . The method for regeneration as claimed in  claim 1 , wherein a quantity of inlet air to the exhaust duct is regulated with regard to the temperature of the gas flow to the catalytic reactor. 
   
   
       3 . The method for regeneration as claimed in  claim 1 , wherein the inlet air conducted to the exhaust duct is taken upstream of a charge air cooler arranged in the intake air line. 
   
   
       4 . The method for regeneration as claimed in  claim 1 , wherein the inlet air conducted to the exhaust duct is taken downstream of a charge air cooler arranged in the intake air line. 
   
   
       5 . An exhaust aftertreatment system for a diesel engine, comprising an exhaust line with a regeneratable unit located upstream of a catalytic reactor, and a pipe that connects an inlet line of the engine to the exhaust line at a point between the regeneratable unit and the catalytic reactor, permitting shunting of inlet air to the exhaust line for regulating temperature in a gas flow to the catalytic reactor. 
   
   
       6 . The exhaust aftertreatment system as claimed in  claim 5 , wherein the pipe is provided with an adjustable choke for regulating flow through the pipe. 
   
   
       7 . The exhaust aftertreatment system as claimed in  claim 5 , wherein the catalytic reactor comprises a selective catalyst reactor for NOx reduction of the exhaust flow. 
   
   
       8 . The exhaust aftertreatment system as claimed in  claim 7 , wherein the regeneratable unit comprises a particle filter. 
   
   
       9 . The exhaust aftertreatment system as claimed in  claim 5 , wherein the catalytic reactor comprises a clean-up catalyst which is located downstream of a lean NOx absorber. 
   
   
       10 . The method for regeneration as claimed in  claim 2 , wherein the inlet air conducted to the exhaust duct is taken upstream of a charge air cooler arranged in the intake air line. 
   
   
       11 . The method for regeneration as claimed in  claim 2 , wherein the inlet air conducted to the exhaust duct is taken downstream of a charge air cooler arranged in the intake air line. 
   
   
       12 . The exhaust aftertreatment system as claimed in  claim 6 , wherein the catalytic reactor comprises a selective catalyst reactor for NOx reduction of the exhaust flow. 
   
   
       13 . The exhaust aftertreatment system as claimed in  claim 12 , wherein the regeneratable unit comprises a particle filter. 
   
   
       14 . The exhaust aftertreatment system as claimed in  claim 5 , wherein the catalytic reactor comprises a clean-up catalyst which is located downstream of a lean NOx absorber. 
   
   
       15 . The exhaust aftertreatment system as claimed in  claim 6 , wherein the catalytic reactor consists of a selective catalyst reactor for NOx reduction of the exhaust flow. 
   
   
       16 . The exhaust aftertreatment system as claimed in  claim 15 , wherein the regeneratable unit consists of a particle filter. 
   
   
       17 . The exhaust aftertreatment system as claimed in  claim 5 , wherein the catalytic reactor consists of a clean-up catalyst which is located downstream of a lean NOx absorber.