壁面散热对天然气柔和燃烧器NO_x排放影响研究  

Effect of Wall Heat Dissipation on NO_x Emission of Natural Gas Fired MILD Combustion Burner

作　　者：徐瑞 朱子儒 陈卫杰 张环[1,2,3] 熊燕 XV Rui;ZHU Zi-ru;CHEN Wei-jie;ZHANG Huan;XIONG Yan(Key Laboratory of Advanced Energy and Power (Institute of Engineering Thermophysics),Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academic of Sciences,Beijing 100049,China;Research Center for Clean Energy and Power,Chinese Academy of Sciences,Jiangsu Lianyungang 222069,China)

机构地区：[1]中国科学院先进能源动力重点实验室(工程热物理研究所),北京海淀100190 [2]中国科学院大学,北京100049 [3]中国科学院能源动力研究中心,江苏连云港222069

出　　处：《当代化工》2018年第12期2494-2498,共5页Contemporary Chemical Industry

基　　金：国家重点基础研究发展计划(973计划)青年科学家项目计划;项目号:2014CB247500

摘　　要：随着"煤改气"的逐步推进,天然气锅炉应用越来越多,在保证效率的同时,锅炉的NO_x排放标准也越来越严格。以应用于锅炉的柔和燃烧器为研究对象,通过实验和化学反应模型的方法研究了柔和燃烧器在不同换热情况(石英玻璃罩和水套)下NO_x排放特性,并对不同工况进行了分析。结果表明,燃烧器散热越大,越有利于降低NO_x排放,当量比小于0.9时,NO_x排放低于30 mg/Nm^3,可以直接满足现有锅炉排放需求。模拟结果显示相对NO_x随散热量呈负相关变化趋势。相对NO_x随当量比的变化曲线随着散热量的增加而变得更加平缓,说明散热量增大会减弱当量比对相对NO_x的影响,使其在不同当量比下的下降程度相当。分析其原因是散热量增大,燃烧室内温度整体下降,烟气在高温区的停留时间减小,热力型NO_x的影响在减弱,快速型NO_x及N_2O型NO_x对整体NO_x的贡献在增强。With the progress of coal-to-gas conversion, more and more gas-fired boilers have been used. At the same time, the NOx emission standards for boilers have become increasingly stringent. In this study, the NOx emission characteristics of the MILD(Moderate or Intense Low-oxygen Dilution) combustion burner under different heat dissipation conditions (quartz tube and water jacket) were studied by using experiments and chemical reaction model simulations. The results showed that the greater the heat dissipation of the burner, the more beneficial to reduce the NOx emission. When the equivalent ratio was less than 0.9, the NOx emission was lower than 30 mg/Nm^3. The simulation results showed that the NOx emissions reduced with heat dissipation increasing. The curves of NOx emissions of different equivalence ratio became smooth as the heat dissipation increased. The results showed that the heat dissipation increased, the flue gas averaged temperature in the burner decreased, the residence time of the flue gas in the high temperature zone decreased, the thermal NOx decreased.

关 键 词：柔和燃烧 壁面散热 NOX排放 

分 类 号：TK16[动力工程及工程热物理—热能工程]