Analysis of low NO emission in high temperature air combustion for pulverized coal
Analysis of low NO emission in high temperature air combustion for pulverized coal
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DOI：
10.1016/j.fuel.2003.12.010
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发表时间：
2004-06
期刊：
影响因子：
7.4
通讯作者：
R. He;Toshiyuki Suda;M. Takafuji;T. Hirata;J. Sato
中科院分区：
文献类型：
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作者：
R. He;Toshiyuki Suda;M. Takafuji;T. Hirata;J. Sato
在大型炉膛中进行了煤粉高温空气燃烧试验，结果表明，高温空气燃烧的NO排放明显低于常温空气燃烧。本文采用简化的化学反应模型对大规模实验中NO的生成进行了数值研究。通过对数值结果的分析，提出了高温空气燃烧的低NO排放机理。HCN浓度越高，NO生成越快。但是，高浓度的HCN和NO的共同作用不会造成快速的破坏。结果表明，通过合理布置流型，可以在一次风喷嘴附近获得较高的HCN和NO浓度。因此，NO的产生和破坏可以达到一个平衡点，从而使NO的净排放量较低。
High temperature air combustion experiments for pulverized coal in a large-scale furnace have been done before and shown that the NO emission in the high temperature air combustion is significantly lower than that in the normal temperature air combustion. This paper numerically studies the NO evolution in the large-scale experiments with a simplified chemical reaction model. Through an analysis of numerical results a low NO emission mechanism in the high temperature air combustion has been presented. If the HCN concentration is high, the NO generation is fast. But, the high HCN and NO concentrations together will make NO destruction fast. It is found that, by properly arranging flow patterns, the high HCN and NO concentrations can be obtained in the vicinity of primary air nozzle. Thus, the generation and destruction of NO can reach an equilibrium point so that the net NO emission rate is low.