Leakage analysis and retrofitting plan of economizers in 420 t/h boilers in Lianzhou Power Plant

The leakage of the economizers in 420 t/h boilers in Lianzhou Power Plant becomes very severe after twoodd years service of the boilers.This paper analyzes the causes of the leakage,putting emphasis on the effects of flue gas velocity,fly ash concentration and heating surface layout,etc.on the abrasion of the economizers.According to the circumstances of the plant,the use of the membrane type economizer is suggested as a solution,and specific retrofitting plan is given.