燃煤电站锅炉NO_x排放影响因素的数值模拟分析  

Numerical Simulation and Analysis of the Influencing Factors of NO_x Emissions of Coal-fired Utility Boilers

作　　者：林鹏云[1] 罗永浩[1] 胡瓅元[1] 

机构地区：[1]上海交通大学热能工程研究所,上海200240

出　　处：《热能动力工程》2007年第5期529-533,共5页Journal of Engineering for Thermal Energy and Power

摘　　要：燃煤电站锅炉是氮氧化物(NOx)的主要污染源之一,通过CFD软件平台,使用数值计算的方法对实际电站锅炉不同的燃烧工况进行数值模拟,研究影响燃煤电站锅炉NOx排放的不同因素。计算结果表明:过量空气系数是影响NOx生成的重要因素之一,NOx排放浓度随着过量空气系数的增大而增加;改变二次风配风方式也能影响NOx的生成,在计算的3种工况中,均等型配风生成的NOx浓度最低,倒塔型次之,束腰型最大;改变二次风偏转角度能影响NOx的生成量,NOx排放浓度随着二次风偏转角度的增大而减小。A coal-fired utility boiler is one of the main sources of NOx pollutants.By using a CFD(computational fluid dynamics) software platform and a numerical calculation method,a numerical simulation was performed of various combustion conditions of a utility boiler to study the different factors excercising an influence on NOx emissions of the boiler in question.The calculation results show that the excess air ratio is one of the major factors influencing the production of NOx and the concentration of NOx emissions will increase with an increase of the excess air ratio.A change of the secondary-air distribution mode can also influence the generation of NOx.Among the three combustion conditions being calculated,the concentration of NOx produced by equal air distribution is the lowest followed by that of a reverse-tower type air distribution.The girdled type air distribution has produced the highest concentration.To change the secondary-air deflection angle can influence the amount of NOx produced.The concentration of NOx emissions will decrease in case of an increase in the secondary-air deflection angle.

关 键 词：燃煤锅炉 数值模拟 NOx 排放 影响因素 

分 类 号：TK229.6[动力工程及工程热物理—动力机械及工程]