Burner with internal fume recirculation system

Abstract

Burner (1) with fumes recirculation comprising a first supply duct (2) for supplying fuel, having at least a first inlet opening (3) and a first outlet opening (4) and a second supply duct (5) for supplying a comburent, having at least a second inlet opening (6) and a second outlet opening (7). The burner (1) further comprises suction means (9) configured to move said at least an amount of comburent from the second inlet opening (6) to the second outlet opening (7) and a fumes return duct (10) for fumes generated by the combustion of the flame and configured to promote a re-introduction of the fumes in the burner (1). In particular, the fumes return duct (10) has a third fumes inlet opening (11) arranged at the head (8) of the burner (1) and a third outlet opening (12) placed in fluid communication with the second inlet opening (6) for the comburent to promote an at least partial re-introduction of the combustion fumes in the second supply duct (5). Furthermore, the suction means (9) is configured to promote a movement of the combustion fumes from the fumes return duct (10) to the second supply duct (5).

1 - 10 . (canceled) 
     
     
         11 . A burner with internal fumes recirculation comprising:
 a first supply duct, for supplying fuel, having at least a first inlet opening and a first outlet opening;   a second supply duct, for supplying comburent, having at least a second inlet opening and a second outlet opening, said first outlet opening and second outlet opening being confluent at a head of the burner configured to generate a flame;   suction means configured to suck at least an amount of comburent from an environment outside said burner and to move said at least an amount of comburent from said second inlet opening to said second outlet opening;   a fumes return duct for fumes generated by the combustion of said flame and configured to promote a re-introduction of the fumes in said burner;   wherein said fumes return duct has a third fumes inlet opening arranged at said head of the burner, wherein said fumes return duct has a third outlet opening placed in fluid communication with said second inlet opening for the comburent to promote an at least partial re-introduction of the combustion fumes in said second comburent supply duct, and wherein said suction means is configured to promote a movement of the combustion fumes from said fumes return duct to said second supply duct; and   a heat exchange section interposed between said third inlet opening and said third outlet opening and configured to promote a decrease in the temperature of the combustion fumes during a passage thereof between said third inlet opening and said third outlet opening, wherein said heat exchange section is obtained by means of a heat exchanger interposed between the third inlet opening and the third outlet opening of said fumes return duct;   characterised in that said heat exchanger comprises a tube bundle obtained as a branch of said second supply duct and a shell container obtained as an enlargement of said fumes return duct.   
     
     
         12 . The burner according to  claim 11 , wherein said suction means comprises a mixing chamber having a first port, adapted to be put in fluid communication with an environment outside said burner to allow an inflow of comburent to said mixing chamber, and a second port, adapted to be put in fluid communication with said fumes return duct to promote an inflow of combustion fumes to said mixing chamber, and wherein said suction means are configured to introduce a mixture of the comburent and the combustion fumes in said second supply duct. 
     
     
         13 . The burner according to  claim 12 , comprising adjustment means active on at least one of: said first port and said second port to adjust at least one of: an inflow of comburent through said first port and an inflow of combustion fumes from said second port, respectively. 
     
     
         14 . The burner according to  claim 12 , wherein said suction means comprises a fan arranged downstream of said mixing chamber, said fan being a fan with axial suction and radial emission. 
     
     
         15 . The burner according to  claim 11 , wherein said fumes return duct has a portion at least partially coaxial to said first supply duct. 
     
     
         16 . The burner according to  claim 11 , wherein at least one of said first supply duct and said second supply duct are at least partially inserted in said fumes return duct. 
     
     
         17 . The burner according to  claim 11 , wherein said fumes return duct comprises a portion peripherally arranged around at least one of: said first supply duct and said second supply duct. 
     
     
         18 . The burner according to  claim 11 , wherein said second supply duct is at least partially coaxial to said first supply duct, said first supply duct being at least partially inserted in said second supply duct;
 wherein said first supply duct and said second supply duct define a passage volume for the comburent inside said second supply duct and outside said first supply duct; and   wherein said second supply duct is at least partially inserted in said fumes return duct.   
     
     
         19 . The burner according to  claim 11 , wherein said third inlet opening is arranged in a retracted position at said first outlet opening and/or at said second outlet opening with respect to at least one of: a fuel direction and a comburent supply direction. 
     
     
         20 . The burner according to  claim 11 , comprising an outer casing adapted to at least partially contain said fumes return duct, said first supply duct and said second supply duct, said outer casing having an aeration system configured to promote an air passage between the inside and the outside of the outer casing.