Metallurgical Gas Burner

Abstract

A steam generator gas burner for burning gases of low calorific value comprises a core air tube, a gas tube arranged coaxially around the core air tube to form a gas flow cross section, at least one further tube element arranged coaxially around the gas tube to form a secondary air flow cross section and first swirlers being arranged in the gas flow cross section. The first swirlers are adjustably arranged to allow for the steam generator gas burner to adjust to varying properties of the combustible gas, in particular a fluctuating calorific value, while taking into consideration the respective ignition intensity.

1 . A steam generator gas burner for burning a gas having a low calorific value, comprising:
 a core air tube;   a gas tube arranged coaxially around the core air tube to form a gas flow cross section;   at least one further tube element arranged coaxially around the gas tube to form a secondary air flow cross section; and   first swirlers situated in the gas flow cross section, the first swirlers being adjustably arranged to adjust a tangential velocity component of the gas.   
   
   
       2 . The steam generator gas burner according to  claim 1 , wherein the gas tube arranged coaxially around the core air tube to form an annular gas flow cross section. 
   
   
       3 . The steam generator gas burner according to  claim 1 , wherein the at least one further tube element arranged coaxially around the gas tube to form an annular secondary air flow cross section. 
   
   
       4 . The steam generator gas burner according to  claim 1 , wherein the first swirlers are formed as swirl blades extending in a radial direction of the core air tube. 
   
   
       5 . The steam generator gas burner according to  claim 1 , wherein the first swirlers are rotatably arranged respectively about their longitudinal axis on an outside surface of the core air tube, the first swirlers extending in a radial direction of the core air tube. 
   
   
       6 . The steam generator gas burner according to  claim 1 , wherein the first swirlers are arranged upstream of a mouth region of the core air tube and a mouth region of the gas tube. 
   
   
       7 . The steam generator gas burner according to  claim 1 , further comprising:
 second swirlers arranged in the secondary air flow cross section,   wherein the first swirlers are arranged at a position situated further upstream with respect to the second swirlers.   
   
   
       8 . The steam generator gas burner according to  claim 1 , further comprising:
 a flow directing ring arranged at an end face in a mouth region of the gas tube, the ring having first flow areas and second flow areas, the first flow areas deflecting gas flowing in the gas flow cross section in a first direction towards a burner longitudinal axis, the second flow areas deflecting air flowing in the secondary air flow cross section in a second direction away from the burner longitudinal axis.   
   
   
       9 . The steam generator gas burner according to  claim 8 , wherein the ring is arranged axially adjustably on the gas tube. 
   
   
       10 . The steam generator gas burner according to  claim 8 , wherein the ring has holes. 
   
   
       11 . The steam generator gas burner according to  claim 10 , wherein an area of the ring which covers the gas flow cross section of the gas tube is formed as a perforated plate. 
   
   
       12 . The steam generator gas burner according to  claim 8 , wherein the ring is composed of one of a heat-resistant sheet metal, a ceramic material and a cast metal. 
   
   
       13 . The steam generator gas burner according to  claim 8 , wherein the ring is composed of one a centrifugally cast metal. 
   
   
       14 . The steam generator gas burner according to  claim 8 , wherein the ring is at least one of cooled and provided with a ceramic coating.