Abstract: The effects of gas compositions on 上計NOx reduction and NH3 slip by selective non-catalyti短計c reduction (SNCR) with NH3 were investigated in a si嗎見mulated cement precalcine兒呢r atmosphere. The results show that文下 the presence of H2O improves NOx reduc師月tion and widens the re樂刀duction temperature win醫些dow significantly. O2 is indispensable for reducin醫資g NOx. The optimum reduc樹空tion temperature decreases and t花頻he temperature windo友房w widens to a lower 年睡temperature with the increase of O2 content. In addition,務個 the increase of O2 content also results in a decrease國子 of the maximum NOx reduction e冷自fficiency. The effect of SO2 on NOx reduction is negligible 可女in the simulated precalci員嗎ner atmosphere. To increa來也se CO concentration mak可木es NO reduction take place a議船t relatively low temperatures.照金 However, NH3 will tend to be oxidized in知場to NO instead of reducing N玩費O after entering the stream玩相 containing O2 at high temperatures if it is in雜個itially blended with a high c拿師oncentration of CO in an oxygen-fr師歌ee environment. The increase of H2O, O2, SO2 or CO concentration is h快多elpful to reduce NH3 slip in the temperature region below 9喝畫00 °C. These effects are r木匠esulted from the fact自聽 that the generation a愛森nd consumption of O and OH r銀吧adicals which are crucial to開近 NO reduction and formation 信司can be influenced by the 呢現four gas compositions.有店 In industrial operatio著老n of SNCR for cement precalciner, t器很hese effects should be t員地aken into account to increa呢白se NOx reduction efficiency and avoi土黑d NH3 slip.
