Exhaust gas after treatment system with temperature control

Abstract

A vehicle emission control system is configured to operatively receive exhaust gas from a combustion engine and includes an exhaust gas after treatment system (EATS) configured to operatively clean the received exhaust gas, a burner unit configured to operatively heat the received exhaust gas to a predetermined temperature before the exhaust gas is provided to the EATS, and a pump unit configured to operatively provide the burner unit with air to be used by the burner unit in a heating process. The pump unit is configured to be operatively propelled by exhaust gas, and the burner unit is arranged upstream the pump unit such that exhaust gas from the burner unit is operatively provided to the pump unit for propelling the pump unit.

1 . A vehicle emission control system configured to operatively receive exhaust gas from a combustion engine and comprising an exhaust gas after treatment system configured to operatively clean the received exhaust gas, a burner unit configured to operatively heat the received exhaust gas to a predetermined temperature before the exhaust gas is provided to the exhaust gas after treatment system, and a pump unit configured to operatively provide the burner unit with air to be used by the burner unit in a heating process, wherein:
 the pump unit is configured to be operatively propelled by exhaust gas, and   the burner unit is arranged up-stream the pump unit such that exhaust gas from the burner unit is operatively provided to the pump unit for propelling the pump unit.   
     
     
         2 . A vehicle emission control system according to  claim 1  comprising a first gas directing arrangement ( 150   a ;  150   b ) configured to operatively direct at least a portion of the exhaust gas from the combustion engine to the pump unit for propelling the pump unit. 
     
     
         3 . A vehicle emission control system according to  claim 2 , wherein: the first gas directing arrangement comprises a pump valve arrangement configured to operatively adjust the portion of the exhaust gas provided from the combustion engine to the pump unit. 
     
     
         4 . A vehicle emission control system according to  claim 1  comprising a second gas directing arrangement configured to operatively direct a portion of exhaust gas from the combustion engine to the burner unit for heating. 
     
     
         5 . A vehicle emission control system according to  claim 4 , wherein: the second gas directing arrangement comprises a burner valve arrangement configured to operatively adjust the portion of exhaust gas provided from the combustion engine to the burner unit. 
     
     
         6 . A vehicle emission control system according to  claim 1 , wherein: the burner unit and the pump unit are both arranged up-stream the exhaust gas after treatment system. 
     
     
         7 . A vehicle emission control system according to  claim 1 , wherein: the burner unit is arranged up-stream the exhaust gas after treatment system and the pump unit is arranged downstream the exhaust gas after treatment system. 
     
     
         8 . A vehicle emission control system according to  claim 1 , wherein: the pump unit comprises a turbine driven compressor configured to be operatively propelled by exhaust gas from the burner unit so as to compress and pump air into the burner unit for the heating process therein. 
     
     
         9 . A vehicle emission control system according to  claim 1 , wherein: the pump unit is configured to operatively provide surplus air into an emission cleaning unit of the exhaust gas after treatment system so as to cool the emission cleaning unit. 
     
     
         10 . A vehicle emission control system according to  claim 9 , wherein: the emission cleaning unit is an emission cleaning catalyst unit arranged downstream of an exhaust gas filter unit in the exhaust gas after treatment system. 
     
     
         11 . A method for controlling the temperature of exhaust gas received from a combustion engine in an exhaust gas after treatment system that is configured to clean the received exhaust gas, the method comprising:
 receiving exhaust gas from the combustion engine,   heating the received exhaust gas in a burner unit to a predetermined temperature before the received exhaust gas is provided to the exhaust gas after treatment system,   providing the burner unit with air for a heating process in the burner unit using a pump unit,   propelling the pump unit by exhaust gas from the burner unit.   
     
     
         12 . The method according to  claim 11 , the method comprising: directing a portion of the exhaust gas from the combustion engine to the pump unit for propelling the pump unit. 
     
     
         13 . The method according to  claim 12 , the method comprising: adjusting the portion of the exhaust gas provided from the combustion engine to the pump unit. 
     
     
         14 . The method according to  claim 11 , the method comprising: directing a portion of exhaust gas from the combustion engine to the burner unit for heating. 
     
     
         15 . The method according to  claim 14 , the method comprising: adjusting the portion of exhaust gas provided from the combustion engine to the burner unit. 
     
     
         16 . The method according to  claim 11 , the method comprising: providing the received exhaust gas heated by the burner unit from the burner unit to the exhaust gas after treatment system being arranged downstream of the burner unit and the pump unit. 
     
     
         17 . The method according to  claim 11 , the method comprising: providing the received exhaust gas heated by the burner unit from the burner unit to the exhaust gas after treatment system being arranged downstream of the burner unit and upstream the pump unit. 
     
     
         18 . The method according to  claim 11 , the method comprising: providing air from the pump unit into an emission control unit of the exhaust gas after treatment system so as to cool the emission control unit. 
     
     
         19 . The method according to  claim 19 , wherein: the emission cleaning unit is an exhaust gas filter unit arranged downstream of an emission cleaning catalyst unit in the exhaust gas after treatment system.