浓淡煤粉燃烧器双通道速度差对NOx排放的影响

Effect of Velocity Difference of Two Channels in Biased Pulverizedcoal Concentration Burners on NOx Emissions

摘要:

对350 MW电站四角切圆煤粉锅炉燃烧过程和煤粉燃烧器气固两相流的数值计算表明,常规浓淡煤粉燃烧器的双通道速度差为6~9 m·s-1,因此,提出了等速型浓淡煤粉燃烧器的概念.等速型浓淡煤粉燃烧器比常规直流煤粉燃烧器可减少21.8%的NOx排放,比常规浓淡煤粉燃烧器也可降低11.3%的NOx排放.

关键词:煤粉燃烧器; 双通道速度差; 风煤比

Abstract:

Combustion in a 350MW tangentially coalfired boiler and gassolid flow of pulverizedcoal burners are simulated.The numerical results show that the velocity difference of two channels are 6~9 m·s-1 in conventional biased pulverizedcoal concentration burners.A biased pulverizedcoal concentration burner with the same velocity of two channels is proposed, NOx emissions of which is 21.8%lower than that of the conventional linear flow pulverized coal burners,11.3% lower than that of the conventional biased pulverized coal concentration burners.

Key words:pulverized coal burner; velocity difference of two channels; gassolid flux rate