新型煤粉燃烧器的燃烧机理分析  

Combustion Mechanism Analysis of New-type Pulverized Coal Burner

作　　者：樊泉桂[1] 

机构地区：[1]华北电力大学,河北保定071003

出　　处：《广东电力》2010年第4期45-50,共6页Guangdong Electric Power

摘　　要：分析了国内超临界和超超临界锅炉采用的几种新型煤粉燃烧器的燃烧机理。主要特点是采用多级配风技术灵活控制燃烧器出口的煤粉火焰燃烧过程;实现着火初期低氧燃烧和火焰内NOx还原技术;在旋流式燃烧器内采用煤粉浓缩技术和环形齿状稳燃器或直流过渡风,在喷口附近煤粉气流着火初期,加强热烟气回流和维持高温及低氧燃烧,促进挥发分析出过程中的NOx还原,并实现快速着火和低负荷稳定燃烧;在A-PM型直流式燃烧器上采用带扩压管的缩放型小喷口结构,增强稳燃能力和维持高温和低氧燃烧,促进NOx还原,并均衡火焰温度,降低水冷壁的热负荷;设置可调节燃尽风进一步提高炉内脱氮效果和提高燃烧效率等。This paper analyzes the combustion mechanism of several new-type pulverized coal burners adopted in the indigenous（ultra） supercritical pressure boiler.The main features include adopting multistage air distribution technique to flexibly control the pulverized coal flame combustion process of burner＇s outlet;realizing low-oxygen combustion in the initial stage of ignition and NOx reduction technique in the flame;adopting pulverized coal concentration technique and ring-shape dentate flame holder or once-through transition air in the cyclone burner,strengthening hot gas back flow and keeping high-temperature and low-oxygen combustion in the initial stage of ignition in the vicinity of exhaust nozzle of burner to promote NOx reduction in the process of volatile matter＇s separation and realize quick ignition and steady combustion at low load;adopting zoom-type small nozzle structure with diffuser in the A-PM type impellerless burner to strengthen the ability of steady-state combustion,keep high-temperature and low-oxygen combustion,promote NOx reduction,balance the temperature of flame and decrease the thermal load of water-cooled wall;arranging adjustable overfire air to further raise furnace de-NOx effect and improve combustion efficiency etc.

关 键 词：超临界锅炉 煤粉燃烧器 稳燃 火焰内脱氮 机理分析 

分 类 号：TK223[动力工程及工程热物理—动力机械及工程]