Abstract: The slag chunks were formed and fell off frequently in the boiler of 1000MW unit of Zouxian Power Plant of Huadian Power International Corporation Limited, and these caused some accidents such as the emergency door of the slagoff machine was opened by bulge force, the water seal of boiler was lost, etc. After reducing load at night, the sound had be often listened which was caused by big slag chunks falling, and obvious vibration can be felt in central control room, and the safety and stable operation of the unit had been influenced seriously. Combining with practical situation, the slagging reasons of the 1000MW boiler were analyzed, and concrete preventing measures were proposed.

Key words: boiler slagging, combustion adjustment, solving measures