在理想平推流反应器中进行了模拟热解气对模拟烟气中NO、N2O的还原实验研究,考察了反应温度、过剩空气系数,模拟热解气中CH4、CO、H2、NH3入口浓度与模拟烟气中NO、N2O入口浓度对NO、N2O与总氮转化率的影响.结果表明,向NH3添加可燃气体CO、H2、CH4可使NO还原窗口向低温方向移动150～200 K,该温度窗口为1073 ～1 223 K;但NH3-COH2-CH4-O2体系对NO、N2O的还原分解作用依赖于体系的O2浓度,仅在富燃料情形(过剩空气系数λ为0.6)下可分别达60.6％、100％的NO、N2O脱除率；在反应温度1073～1223 K及过剩空气系数λ为0.6条件下,较高的热解气CH4、CO、H2浓度可增加NO排放,但有利于还原N2O；增加NH3入口浓度可增加NO分解率.%Reduction of NO and N2O with the simulated pyrolysis gas of NH3-CO-H2-CH4-O2 mixture was experimentally studied in an ideal plug flow reactor. The effects of temperature, excess air number A, concentration of CH4, CO, H2, NH3 in the simulated pyrolysis gas, concentration of NO and N2O in the simulated flue gas on reduction of NO, N2O and total nitrogen conversion efficiency were experimentally investigated. The results show that adding combustible or reducing species of CO, H2, CH4 into NH3 can decease about 150 -200 K of temperature range or window for reducing NO, the obtained optimal temperature range of reducing NO is in a range of 1 073 ~ 1 223 K. The excess air number A or oxygen content in NH3-CO-H2-CH4-O2 mixture shows an important influence on reduction of NO and N2O. When the excess air number λ is controlled as 0.6, I. E. , similar to the case of fuel-rich, the maximum decomposition ratio of NO and N2O in the simulated flue gas reaches 60.6% and 100% , respectively. When the excess air number A is kept at 0. 6 in a temperature range of 1 073 ~ 1 223 K, higher concentration of CH4, CO, H2 in the simulated pyrolysis gas can result in an effectively decomposition of N2O, but lead to an increase of NO; however, higher conversion efficiency of NO can be achieved under the condition of increasing the concentration of NH3 in the simulated pyrolysis gas.
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