不同燃烧布置型式的660MW超临界锅炉燃烧偏差分析

Burning Deviation Analysis of 660 MW Supercritical Boiler with Different Combustion Layout

利用炉膛热力计算,探究660MW超临界锅炉屏式过热器底部温度及烟气流速等因素变化对机组各受热面吸热量的影响。结合机组运行数据分析造成燃烧偏差的主要原因。对于四角切圆燃烧锅炉,通过调整燃烧器摆角,降低炉膛上部受热面两侧屏底温度偏差,使屏式受热面两侧汽温偏差显著降低。通过调整燃尽风(SOFA风),减小了炉膛出口烟气残余旋转的影响,降低汽温偏差。对于对冲燃烧锅炉,通过调整旋流燃烧器外二次风,降低了炉宽方向上的屏底温度偏差使末级过热器和再热器沿炉宽方向中间位置的壁温有所下降,主蒸汽和再热蒸汽欠温现象得到改善。

Using furnace thermodynamic calculation, this paper explored the influences of the bottom temperature and flue gas velocity on the heat absorption of heating surface of the 660MW supercritical boiler. The main reason of combustion deviation was analyzed through the operation data. For the corner tangentially fired boiler, the temperature deviation at the bottom of the heating surface was reduced by adjusting the swing angle, so that the deviation of the steam temperature on both sides of the heating surface of separating and rear screen was reduced obviously. And the unfavorable influence of the flue gas flow deviation was reduced by adjusting the SOFA wind, so that the deviation of the steam temperature was reduced slightly. For the opposed firing boiler B, the temperature deviation in the direction of furnace width was reduced by adjusting the swirl burner, resulting in that the wall temperature of the final stage superheater and reheater, near the middle position along the width direction of the furnace was reduced, the steam under-temperature phenomenon is improved.