为解决某国产350MW超临界机组建成投运后出现的低负荷工况下主蒸汽及再热蒸汽温度过低、汽温偏差大、屏式过热器管壁超温等严重影响到机组安全稳定运行的问题，采用现场燃烧调整试验，改变主燃烧器投运方式、调节SOFA燃烧器风门开度及角度、增大过热烟气挡板开度和运行氧量。结果表明：该机组在175MW负荷下使用中间三层燃烧器组成的投运方式效果更佳；调整后主/再热汽温提高20℃以上，两侧汽温偏差降低至1.5℃以内，受热面超温问题得到解决，找到了适合锅炉低负荷安全稳定运行的最佳方式；为同类型机组带低负荷时的燃烧调整和优化运行提供新的参考方案。

After a domestic 350MW supercritical unit was put into operation, there has been a low load conditions the main steam and reheat steam temperature is too low, great steam temperature deviation, platen superheater tube wall overtemperature problems seriously affect the security unit. To this end, on-site combustion adjustment tests were carried out to change the main burner commissioning mode, adjust the SOFA burner damper opening and angle, increase the superheated flue gas baffle opening and operating oxygen. The results show that the operation mode of the unit using the intermediate three-layer burner under the 175MW load is better than that of the traditional three-layer burner. After reasonable adjustment, the main/reheat steam temperature is increased by 20 °C or more, and the main/reheat steam temperature deviation on both sides is reduced to less than 1.5 °C. The overheating problem of the heated surface is solved, and the parameters such as the carbon content of the fly ash can meet the operational safety regulations. Therefore, the best way to safely and stably operate the boiler with low load has been found, which provides a new reference scheme for the combustion adjustment and optimized operation of the boiler of the same type with low load.

国网河北能源技术服务有限公司科技项目(TSS2018-004)