STUDY ON FLOW-ACCELERATED CORROSION OF CONDENSER FOR DIRECT-AIR-COOLED 300 MW UNIT

The phenomenon of serious flow-accelerated corrosion(FAC) occurred in condenser of air-cooled 300 MW unit in Huaneng Yushe Power Generation Co Ltd has been presented,and the causes leading to FAC being analysed.It is believed that the causes are the Fe3O4 film on surface of the horizontal steam distribution pipes being oxidized,as well as the steam disturbance and the impulse of water drops contained in wet steam passing through the transitional section of steam distritution pipes.Enhancing pH value of feed-water and liquid film on metal surface is helpful to suppress FAC and decrease the influence of corrosion products upon the thermal system,but the amount of added ammonia has to be substantially increased,and affecting the operation of post-continued fine desalting system.