摘要:
A low-NOx boiler comprises a burner for burning gaseous fuel, heat transfer pipes (117) heating water by combustion heat of the burner to generate steam and having a passage (131) through which water flows, a steam drum (128) communicating with the heat transfer pipe and accumulating the steam from the heat transfer pipe, and an exhaust gas duct (114) located in the furnace to exhaust combustion gas generated by combustion of gaseous fuel outside of the boiler. The boiler further comprises unburnt gas burner (126) in the exhaust gas duct (114) for burning unburnt content in the combustion gas flowing in the duct. The unburnt gas burner includes a nozzle (2) for injecting premixture flow of fuel and combustion air and flame holding plate (1) located near the downstream side of the outlet of the nozzle to interrupt the premixture flow to form a circulating flow on downstream side of the flame holding plate. As gaseous fuel and air are mixed in advance and a flame is formed, the flame length can be shortened. Furthermore, the flame holding plate enables to reduce NOx generated. Unburnt gas burner pro`vided in the exhaust gas duct makes it possible to notably reduce the concentration of NOx discharged to the outside of the system.
摘要:
A jet of the premixed gas (5) is burnt from an inside to an outside of the jet to form a premix flame. A burned gas (4) is mixed into the premixed gas from the outside of the jet. The burned gas is produced when premixed gas is burned.
摘要:
A low-NOx boiler comprises a burner for burning gaseous fuel, heat transfer pipes (117) heating water by combustion heat of the burner to generate steam and having a passage (131) through which water flows, a steam drum (128) communicating with the heat transfer pipe and accumulating the steam from the heat transfer pipe, and an exhaust gas duct (114) located in the furnace to exhaust combustion gas generated by combustion of gaseous fuel outside of the boiler. The boiler further comprises unburnt gas burner (126) in the exhaust gas duct (114) for burning unburnt content in the combustion gas flowing in the duct. The unburnt gas burner includes a nozzle (2) for injecting premixture flow of fuel and combustion air and flame holding plate (1) located near the downstream side of the outlet of the nozzle to interrupt the premixture flow to form a circulating flow on downstream side of the flame holding plate. As gaseous fuel and air are mixed in advance and a flame is formed, the flame length can be shortened. Furthermore, the flame holding plate enables to reduce NOx generated. Unburnt gas burner pro`vided in the exhaust gas duct makes it possible to notably reduce the concentration of NOx discharged to the outside of the system.
摘要:
A jet of the premixed gas (5) is burnt from an inside to an outside of the jet to form a premix flame. A burned gas (4) is mixed into the premixed gas from the outside of the jet. The burned gas is produced when premixed gas is burned.