Air preheater is the indispensable equipment for power station boilers. At present
corrosion and ash accumulation are the main problems of air preheater. Due to the low-temperature of flue gas and the hydrogen sulphate caused by ammonia escaping. Different countermeasures are needed for two different reasons. The cause of the blockage of the air preheater is analyzed
and the related measures adopted in recent years to solve the air blockage are introduced