【摘要】 为了探究煤粉燃烧时NO和N₂O的排放特性，首先，在卧式管式炉燃烧实验装置上，考察了燃烧温度和氧体积分数对粉煤燃烧时N₂O和NO排放的影响；其次，通过添加金属氧化物（CaO、Fe₂O₃）的方式，抑制煤粉燃烧时N₂O和NO的生成；最后，利用热重质谱联用分析仪（TG-MS）探讨了金属氧化物对中间体NH₃和HCN生成的影响。研究结果表明：燃烧温度对朔州褐煤N₂O和NO生成的影响最显著，随着燃烧温度升高，NO排放量增加，而当温度超过900℃时N₂O分解较显著，排放质量浓度随之下降；当氧体积分数在10%以下燃烧时，随着氧体积分数升高，燃料N向NO和N₂O的转化率均呈上升趋势；CaO、Fe₂O₃对N₂O催化分解起关键作用，但CaO对NO的抑制作用并不明显；Fe₂O₃和CaO的存在大幅降低煤粉热解时N₂O主要前驱体HCN的质量浓度，且在600℃以上的高温段抑制效果更加明显，但CaO促进NH₃的生成。更多还原

【Abstract】 In order to explore the emission characteristics of NO and N₂O during pulverized coal combustion, firstly, the formation characteristics of N₂O and NO during the combustion of Shuozhou lignite were studied on a horizontal tube furnace combustion experimental device. The effects of combustion temperature and oxygen volume fraction on N₂O and NO emissions during pulverized coal combustion were investigated. Secondly, the formation of N₂O and NO during pulverized coal combustion was inhibited by adding metal oxides（CaO, Fe₂O₃）. Finally, the effects of metal oxides on the formation of intermediates NH₃ and HCN were investigated by thermogravimetric mass spectrometry（TG-MS）. The results show that the combustion temperature has the most significant effect on the formation of N₂O and NO in Shuozhou lignite. As the combustion temperature increases, the NO emission increases. However, when the temperature exceeds 900 ℃, the N₂O decomposition is more significant, and the emission peak decreases. When the oxygen volume fraction is below 10 %, the conversion rate of fuel N to NO and N₂O increases with the increase of oxygen volume fraction. CaO and Fe₂O₃ play a key role in the catalytic decomposition of N₂O, but the inhibitory effect of CaO on NO is not obvious. The presence of Fe₂O₃ and CaO greatly reduces the mass concentration of HCN, the main precursor of N₂O during coal pyrolysis, and the inhibition effect is more obvious at high temperature above 600 ℃. However, CaO has a certain promoting effect on the formation of NH₃.更多还原