Burner structure

Abstract

To provide a low combustibility fuel firing burner that can ensure high ignition performance and combustion stability even if a gas flow rate is changed along with changes in boiler load or the like. A low combustibility fuel firing burner separates a pulverized low combustibility fuel supplied together with an air with a separator, distributing the separated fuel to a rich portion nozzle and a lean portion nozzle provided in a furnace, and burning the fuel, in which a variable control part such as a core or a flow adjusting/blocking valve is provided in at least one of a high-particle-concentration gas pipe extending from a downstream side of the separator and communicating with the rich portion nozzle and a low-particle-concentration gas pipe extending from the downstream side of the separator and communicating with the lean portion nozzle.

1 . A low combustibility fuel firing burner for separating a pulverized low combustibility fuel supplied together with an air with a separator, distributing the separated fuel to a rich portion nozzle and a lean portion nozzle provided in a furnace, and burning the fuel, wherein a variable control part for changing a flow path sectional area is provided in at least one of a gas flow path extending from a downstream side of the separator and communicating with the rich portion nozzle and a gas flow path extending from the downstream side of the separator and communicating with the lean portion nozzle.  
   
   
       2 . The low combustibility fuel firing burner according to  claim 1 , wherein the variable control part is a movable resistor provided in a gas flow path for supplying a high-particle-concentration gas from the separator to the rich portion nozzle.  
   
   
       3 . The low combustibility fuel firing burner according to  claim 1 , wherein the variable control part is a flow adjusting/blocking valve provided in a gas flow path for supplying a low-particle-concentration gas from the separator to the lean portion nozzle.  
   
   
       4 . The low combustibility fuel firing burner according to  claim 1 , wherein a wall against which a low combustibility fuel supplied into the separator collides is given a hardwearing finish.  
   
   
       5 . A low combustibility fuel firing burner for separating a pulverized low combustibility fuel supplied together with an air with a separator, distributing the separated fuel to a rich portion nozzle and a lean portion nozzle provided in a furnace, and burning the fuel, wherein a blowoff angle of the rich portion nozzle and a blowoff angle of the lean portion nozzle are offset in a vertical direction.  
   
   
       6 . A low combustibility fuel firing burner for separating a pulverized low combustibility fuel supplied together with an air with a separator, distributing the separated fuel to a rich portion nozzle and a lean portion nozzle provided in a furnace, and burning the fuel, wherein a blowoff angle of the lean portion nozzle is offset to a furnace wall side in a horizontal direction.