摘要
在一台HG-410/9.8-YW15型锅炉上进行了常规细度煤粉再燃示范,研究了再燃燃料质量比、燃尽风率、炉膛出口氧气体积分数和磨煤机投运方式等运行参数对再燃效果的影响.采用常规煤粉再燃可在不影响锅炉蒸汽参数和锅炉效率的前提下大幅降低NOx排放.当再燃燃料质量比大于24%时,提高再燃燃料比例对于提高NOx脱除效率意义不大.提高燃尽风率可以明显降低锅炉NOx排放,同时飞灰可燃物质量分数变化很小.炉膛出口氧气体积分数不仅影响NOx排放水平,还是影响飞灰可燃物质量分数的关键因素;综合考虑两方面,氧气体积分数一般不宜低于2.9%.虽然三次风布置在主燃区,三次风量对NOx排放的影响仍十分明显,三次风量增大,NOx生成量显著提高.再燃技术方案在锅炉低负荷运行时仍能将NOx排放控制在较低水平.
The conventional pulverized-coal was reburned on a HG-410/9.8-YW15 boiler. The effect of the mass ratio of reburning fuel, the ratio of overfire air （OFA）, the oxygen volume fraction at the furnace exit and the coal mill running condition on the reburning was studied. The conventional pulverized-coal reburning can markedly reduce the nitrogen oxide emission with little effect on the steam parameter and the boiler efficiency. When the mass ratio of reburning fuel is larger than 24%, its increasing has little effect on nitrogen oxide reduction. The nitrogen oxide emission can be reduced largely and the carbon mass fraction in the fly ash changes little by increasing the ratio of OFA. The oxygen volume fraction at the boiler exit has magnitude effect on both the nitrogen oxide emission and the carbon mass fraction in the fly ash; the optimal value of oxygen volume fraction is above 2.9 %. The nitrogen oxide emission increases with the tertiary air increasing although the tertiary air is posed in the main combustion zone. The nitrogen oxide emission can be still controlled on a lower level when operating at low load by adopting the conventional pulverized-coal reburning.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2008年第10期1751-1755,共5页
Journal of Zhejiang University：Engineering Science
关键词
常规煤粉再燃
氮氧化物
再燃燃料质量比
燃尽风率
三次风
conventional pulverized-eoal reburning
nitrogen oxide
mass ratio of reburning fuel
ratio ofoverfire air
tertiary air
