基于FGR的低氮燃烧器NO_(x)生成的影响因素研究

Study on Effect of External Circulation Rate of Flue Gas on NO_(x)Production with FGR and Low Nitrogen Burner

近几年,随着各地对工业锅炉氮氧化物排放标准日趋严格,各种低氮燃烧技术也被广泛应用在燃气锅炉低氮改造工程中。以某锅炉提标改造工程为例,基于烟气外部循环和新型低氮燃烧器的组合技术路线,在11.2 MW天然气热水锅炉上,研究了不同锅炉负荷、空气过剩系数及烟气外循环率对锅炉烟气中氮氧化物生成的影响。结果表明,随着锅炉负荷的增加,氮氧化物的生成有一定的增加,但不明显。随着空气过剩系数的增加,氮氧化物的生成增到到一定限度后逐渐减少。烟气再循环率对NO_(x)的生成具有十分重要的影响,烟气中氮氧化物的含量随着烟气循环率的增加,呈现出非线性降低的趋势。

In recent years,with the stricter emission standards of nitrogen oxides from industrial boilers,various low nitrogen combustion technologies have been widely used in low nitrogen transformation projects of gas boilers.Taking the boiler standard lifting and reconstruction project as an example,based on the combined technical route of flue gas external circulation and low nitrogen burners in 11.2MW natural gas hot water boiler,the effects of different flue gas external circulation rates on nitrogen oxide emission from boiler flue gas and boiler operation stability are studied in this paper.It turns out that with the increase of boiler load,the formation of NO_(x)increase to a certain extent,but not significantly.With the increase of excess air coefficient,the formation of NO_(x)increase to a certain extent after gradually reduce.Flue gas recycling rate has important effects on NO_(x)emission,the emission of NO_(x)in flue gas with the increase of flue gas circulation rate,shows the tendency of new nonlinear reduced.