Heat Surface Retrofit of a 225 t/h Pulverized Coal Boiler

Troubles such as severe erosion of economizer tube banks,too high temperature of exhaust gas and great heat loss of boiler etc were encountered by a 225 t/h natural circulation pulverized coal-fired boiler of Shanxi Tianji Coal Chemical Industry Group Co.Ltd.during operation.Moreover,after capacity expansion of its ammonia plant,feed water temperature of the boiler got raised,and under individual working conditions,some thermal parameters were found to be deviating from design values.To solve above problems,a technical retrofit has been proposed and made to the economizer and relevant superheater heat surfaces,of which the retrofit result is presented as well.