Abstract: The effects of gas compositions嗎女 on NOx reduction and NH3 slip by selective non-catal筆到ytic reduction (SNCR) with NH3 were investigated in a si歌放mulated cement precalciner 家街atmosphere. The results和費 show that the prese去他nce of H2O improves NOx reducti照不on and widens the reduction te好外mperature window significantly. O2 is indispensable for reducing N知哥Ox. The optimum reduction te白事mperature decreases 老歌and the temperature wi北相ndow widens to a lower tem笑到perature with the in就聽crease of O2 content. In addition, the incre刀爸ase of O2 content also results in a decrea都鄉se of the maximum NOx reduct去要ion efficiency. The effec近暗t of SO2 on NOx reduction is negligible 外家in the simulated precalciner atmosph黃現ere. To increase CO conc討數entration makes NO redu你城ction take place at rel從村atively low temperatures. How會筆ever, NH3 will tend to be oxidi門西zed into NO instead of red明對ucing NO after entering師北 the stream containing O2 at high temperatures if it 不音is initially blended with a h市快igh concentration of CO in an oxyge討書n-free environment. The increase 火城of H2O, O2, SO2 or CO concentration is helpful to老家 reduce NH3 slip in the temperature region bel制紙ow 900 °C. These effects a體店re resulted from the 東睡fact that the generation and con來用sumption of O and OH radicals which are志朋 crucial to NO reduction and fo東村rmation can be influenced by the 如吧four gas compositions. In i了線ndustrial operation of 藍高SNCR for cement precalciner, the電鐵se effects should be 的又taken into account to incre熱頻ase NOx reduction efficien微腦cy and avoid NH3 slip.
