超超临界锅炉湿、干态转换过程中防止水冷壁超温的措施

Measures for preventing water wall overheating in wet/dry state transition process of ultra supercritical boiler

墙式切圆燃烧的超超临界锅炉在由湿态向干态转换时,因投射热负荷增加及管内介质换热系数降低,很容易引起垂直水冷壁管壁超温。结合湖北西塞山发电有限公司680 MW超超临界锅炉的启动调试经验,对转换期间燃烧器背火侧区域水冷壁管管壁超温的原因进行了分析并提出了具体的防范措施。

In the wet-to-dry state transition process of the wall tangential firing ultra supercritical boiler,due to that the radiated heat load increases and the heat exchange coefficient of the medium inside pipe reduces,the tubes of the vertical water wall may be overheat easily.Combining with the experience of starting and debugging of the 680MW ultra supercritical boiler in Hubei Xisaishan Power Generation Company Limited,the reasons of overheat of water wall tubes in back fire side in wet/dry state transition process were analyzed,and concrete preventive measures were put forward.