Set of thermal afterburners

Abstract

A set of thermal afterburners is described, whose members to a large extent possess the same construction: They have a housing with an inlet for gas to be purified and with an outlet for purified gas. The gas to be purified is freed from impurities with the aid of a burner in a combustion chamber. To conserve energy a heat exchanger is provided, which comprises a plurality of substantially parallel heat exchanger tubes. With the aid of this heat exchanger heat is recovered from the hot gas leaving the combustion chamber and fed to the gas ducted to the combustion chamber. The various members of the set of thermal afterburners now vary in the efficiency level of the heat exchanger, in order to be able to produce a different outlet temperature of the purified gas for each member. For this purpose, the heat exchanger tubes are provided on their surface with elevations and/or recesses, which alter the effective heat exchanger surface area in comparison to smooth-walled tubes. The various members of the set of thermal afterburner now vary substantially exclusively through the density and/or height of the elevations and/or depth of the recesses, but not in the remaining construction, in particular the dimensioning of the various components. In this way, different thermal afterburners can be manufactured at low cost, in the case of which the outlet temperature of the purified gases is adapted to the different needs of the plant connected downstream.

1 . Set of thermal afterburners having members comprising: 
 a) a housing, which possesses an inlet for gas to be purified and an outlet for purified gas;    b) a burner arranged within the housing;    c) a combustion chamber arranged within the housing, to which the gas to be purified can be ducted and in which the burner produces a flame;    d) a heat exchanger comprising a plurality of heat exchanger tubes, with which heat can be recovered from the hot gas leaving the combustion chamber and to which the gas ducted to the combustion chamber is fed; wherein    e) the outside surfaces of the heat exchanger tubes are provided at least in sections with at least one of elevations and recesses;    f) at least one of the density and height of the elevations and depth of the recesses and size of areas, provided with the at least one of the elevations and recesses, for which various members of the set of thermal afterburners are different, while the remaining construction of the various members of the set is substantially identical.    
   
   
       2 . Set of thermal afterburners according to  claim 1 , wherein gas to be purified flows through the heat exchanger tubes ( 10 ) and purified gas flows over their outer surface.  
   
   
       3 . Set of thermal afterburners according to  claim 1  wherein the housing possesses a removable cover.  
   
   
       4 . Set of thermal afterburners according to  claim 1 , wherein a longitudinal axis of the housing runs vertically.  
   
   
       5 . Set of thermal afterburners according to  claim 2  wherein the housing possesses a removable cover.  
   
   
       6 . Set of thermal afterburners according to  claim 2 , wherein a longitudinal axis of the housing runs vertically.  
   
   
       7 . Set of thermal afterburners according to  claim 3 , wherein a longitudinal axis of the housing runs vertically.