Abstract: The effects of gas compositions站們 on NOx reduction and NH3 slip by selective non-catalytic r嗎答eduction (SNCR) with NH3 were investigated in a simulated cement算刀 precalciner atmosphere. T業村he results show that the presen分少ce of H2O improves NOx reduction and widens 空懂the reduction tempera和長ture window significantly. O2 is indispensable for reducing NOx. The筆著 optimum reduction temperature dec制媽reases and the temperature window wi時道dens to a lower temperatu煙章re with the increase of O2 content. In addition, the incr相就ease of O2 content also results in a decrease聽技 of the maximum NOx reductio樹答n efficiency. The effect of SO2 on NOx reduction is negligibl匠外e in the simulated pr了個ecalciner atmosphere. T術腦o increase CO concentration makes NO 老東reduction take place at relatively 他林low temperatures. However, NH3 will tend to be oxidized分黑 into NO instead of reducing NO月姐 after entering the stream co男吧ntaining O2 at high temperatures if i林湖t is initially blended with a high c文哥oncentration of CO in an ox話科ygen-free environment. 裡鐵The increase of H2O, O2, SO2 or CO concentration is hel人很pful to reduce NH3 slip in the temperatur又知e region below 900 °C. 身作These effects are resulted from the 了來fact that the generation and consu技站mption of O and OH radicals which are 信個crucial to NO reduction and form筆唱ation can be influenced by the four g在少as compositions. In industrial op門你eration of SNCR for cement precal紙書ciner, these effects should 又間be taken into account to increas喝土e NOx reduction efficiency and av空畫oid NH3 slip.
