双分级可调低NO_x燃烧技术

Dual staging adjustable low NO_x combustion technology

依据锅炉负荷与氧量的相关性探讨了锅炉运行氧量特性,并以此分析锅炉在低负荷下以SOFA技术运行时NOx排放质量浓度高的原因;同时,从理论上分析了燃料分级燃烧技术与锅炉低负荷工况特性相匹配的原因,在此基础上提出了双分级可调低NOx燃烧技术的设想。认为双分级可调低NOx燃烧技术通过一次风燃烧器沿炉膛高度上的布置方式而实现,通过再燃燃料的调节,可以使炉内燃烧方式在空气分级燃烧与燃料分级燃烧技术之间转换,避免了单一技术的某些固有弊端。该技术可实施性强,风险小,适用于大容量机组锅炉。

On the basis of the correlation between boiler load and oxygen content,the operation oxygen con-tent characteristics of the boiler was discussed,and the reason for high NOx emission when the boiler was running at low load with the SOFA technology was investigated.Moreover,why the fuel staging combus-tion technology is matched with the boiler low load operation condition was theoretically analyzed.On this basis,the dual staging adjustable low NOx combustion technology was proposed,which can be realized by changing the locations of primary air burner along the furnace height direction.Through regulation of the reburned fuel,the furnace combustion can be switched between the air staging combustion and fuel staging combustion,thus the disadvantages of the pure air staging or fuel staging combustion can be avoided.This technology has well feasibility and low risk,therefore,it is suitable to be used in large scale unit boilers.