煤粉燃烧器径向旋流叶片最佳角度研究

Research on Best Angle of Radial Swirl Blade of Pulverized Coal Burner

煤粉旋流燃烧器外二次风旋流强度的大小由燃烧器结构和径向旋流叶片角度决定.根据径向旋流强度定义,建立了反映径向旋流叶片数量、角度对外二次风旋流强度影响的解析模型,从模型计算结果出发,得到径向旋流叶片最佳角度的确定和调整方法,最后在某电厂2070t/h锅炉上应用最佳叶片角度确定和调节方法.现场测试表明:通过将外二次风叶片角度调整到趋于最佳值,可以使锅炉高负荷时燃尽率明显提高,在低负荷时NOx生成特性得到改善,锅炉排烟损失降低.

The swirl intensity of secondary air outside the pulverized coal swirl burner is determined by the burner structure and the radial swirl blade angle.According to the definition of radial swirl intensity,this paper establishes an analytical model reflecting the influence of the number and angle of radial swirl blades on the outer secondary air swirl intensity.From the calculation results of the model,the determination and adjustment method of the optimal angle of radial swirl blades is obtained,and finally applied to a 2070 t/h boiler in a power plant.The field test shows that by adjusting the angle of the outer secondary air blade to the optimal value,the burnout rate of the boiler can be increased at high load,the NO_(x) production can be significantly reduced at low load,and the boiler flue gas heat loss can be reduced.