Boiler blowdown recovery

Abstract

One way to reduce the heat loss of the steam boiler is to reduce the blowdown rate and recover the heat from the purged water. Purging the boiler, although necessary, represents a loss of treated water and a loss of heat because the purged water is water brought to saturation. Blowdown recovery must be done according to the available users/consumers. The paper analyses the recovery of blowdown of a steam boiler of 420 t/h capacity by using a flash separator and a makeup water preheater. The flash steam is used for the feed water deaeration. The heat recovered from the blowdown can reach 97%, and the recovered water can reach 43%.