Gas burner

Abstract

A gas burner includes: a nozzle where gas fuel flows; and a primary air supply part for supplying, from around the nozzle, primary air whose air ratio to the gas fuel is less than 1. The nozzle includes: at least one main hole configured to eject the gas fuel at an ejection angle of not less than 25 degrees and not greater than 45 degrees with respect to a central axis of the gas burner; and at least one sub hole configured to eject the gas fuel at an ejection angle of not less than 35 degrees and not greater than 55 degrees with respect to the central axis of the gas burner, the ejection angle of the sub hole being greater than the ejection angle of the main hole. The gas fuel flowing in the nozzle has a gas pressure of not less than 300 kPa.

1 - 6 . (canceled) 
     
     
         7 . A gas burner disposed in a facility including a furnace, comprising:
 a nozzle where gas fuel flows; and   a primary air supply part for supplying, from around the nozzle, primary air whose air ratio to the gas fuel is less than 1,   wherein the nozzle includes:
 at least one main hole configured to eject the gas fuel at an ejection angle of not less than 25 degrees and not greater than 45 degrees with respect to a central axis of the gas burner; and 
 at least one sub hole configured to eject the gas fuel at an ejection angle of not less than 35 degrees and not greater than 55 degrees with respect to the central axis of the gas burner, the ejection angle of the sub hole being greater than the ejection angle of the main hole, and 
   wherein the gas fuel flowing in the nozzle has a gas pressure of not less than 300 kPa.   
     
     
         8 . The gas burner according to  claim 7 ,
 wherein the gas fuel contains hydrogen.   
     
     
         9 . The gas burner according to  claim 8 ,
 wherein the ejection angle of the main hole is not less than 25 degrees and not greater than 35 degrees, and the ejection angle of the sub hole is not less than 35 degrees and not greater than 45 degrees.   
     
     
         10 . The gas burner according to  claim 7 ,
 wherein the at least one main hole includes a plurality of main holes formed in a tip portion of the nozzle such that the plurality of main holes are disposed around the central axis of the gas burner symmetrically with each other with the central axis of the gas burner therebetween.   
     
     
         11 . The gas burner according to  claim 7 ,
 wherein the at least one sub hole includes a plurality of sub holes formed in a tip portion of the nozzle such that the plurality of sub holes are disposed around the central axis of the gas burner symmetrically with each other with the central axis of the gas burner therebetween.   
     
     
         12 . The gas burner according to  claim 7 ,
 wherein a ratio A1:A2 is between 80:20 and 90:10, where A1 is a total opening area of a plurality of the main holes and A2 is a total opening area of a plurality of the sub holes.   
     
     
         13 . A gas burner disposed in a facility including a furnace, comprising:
 a nozzle where gas fuel containing hydrogen flows; and   a primary air supply part for supplying, from around the nozzle, primary air whose air ratio to the gas fuel is less than 1,   wherein the nozzle includes:
 at least one main hole configured to eject the gas fuel at an ejection angle of not less than 25 degrees and not greater than 35 degrees (excluding 35 degrees) with respect to a central axis of the gas burner; and 
 at least one sub hole configured to eject the gas fuel at an ejection angle of not less than 35 degrees and not greater than 45 degrees (excluding 45 degrees) with respect to the central axis of the gas burner, the ejection angle of the sub hole being greater than the ejection angle of the main hole, and 
   wherein the gas fuel flowing in the nozzle has a gas pressure of not less than 300 kPa.   
     
     
         14 . A facility comprising:
 a furnace, and   the gas burner according to  claim 7 .