Abstract: The condensate processing technology of coal-fired direct air cooling unit is powdex. In the early stage of powdex operation, the water vapor quality is abnormal, and the hydrogen conductivity of boiler water seriously exceeds the standard. Through the inspection and analysis on impurity composition, leakage of powdex and powder resin leachate, it is considered that the excessive concentration of powder resin leachate is the main cause. Therefore, the measures of changing the powder resin and using on-line powdered resin cleaning technology are put forward, After the measures are implemented, the problem is solved to ensure the safe, economical and stable operation of the unit.