Abstract:

An experimental study on the effects of CO content on selective non-catalytic reduction（SNCR）of NO_x was performed in a quartz tube reactor，using ammonia and urea solution as N-agent.The results showed that as the CO content increased：(1）Both the SNCR temperature window and the optimal DeNO_x temperature shifted towards a lower temperature.Simultaneously，the temperature window was narrowed and the optimal DeNO_x efficiency decreased，especially when using ammonia as reductant.(2）The peak of N₂O emission became higher.When using urea solution as the reductant，N₂O emission temperature window extended towards a lower temperature mainly.In the case of ammonia，N₂O emission temperature window extended to both higher and lower temperatures.(3)The slip emission curves of both NH₃ and HNCO shifted to a lower temperature.When setting φ（CO）/φ（urea）constant，the optimal DeNO_x temperature dropped slightly with the increase of ratio of ammonia to nitrogen in the feed（β），and there was no change of the emission regime profiles about NO_x，N₂O，NH₃ and HNCO as β or oxygen content changed.

Key words:

NO_x, 选择性非催化还原, 尿素, 氨水, CO

摘要：

分别以氨水和尿素溶液作为还原剂，在管式反应器上详细研究了CO含量对烟气SNCR（选择性非催化还原）脱硝性能的影响。结果表明，CO含量增加导致：（1）SNCR脱硝温度窗口和最佳脱硝温度向低温方向移动，同时脱硝温度窗口宽度变窄、最大脱硝效率降低，尤其是以氨水作为还原剂时更为突出；（2）N₂O排放的峰值升高；当以尿素溶液作还原剂时，N₂O排放温度窗口主要向低温方向扩展；当以氨水作还原剂时，N₂O排放温度窗口向低温和高温两个方向扩展；（3）NH₃及HNCO残留量曲线向低温方向移动。维持相同的φ（CO）/φ（urea），氨氮比增加将导致最佳脱硝温度略微降低。氨氮比或氧含量的变化对NO_x、N₂O、NH₃及HNCO的排放趋势没有影响。

关键词:

NO_x, 选择性非催化还原, 尿素, 氨水, CO