Abstract:

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 680MW 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.

Key words: ultra supercritical boiler, dry state, wet state, wall tangential, overheat, water wall