Taking the No.3 and No.4 supercritical 660 MW air cooling units in Guohua Dingzhou Power Generation Co.

Ltd.as objects

the optimization of chemical condition in high pH oxygen-adding treatment for supercritical once-through boiler was summarized from aspects such as influence of CO2 controlling upon the system

the service life of anionic exchange resin under high temperature

the type selection of polishing treatment equipment

and the chemical supervision for preventing corrosion of the air cooled condenser

and so on.After adopting the high pH oxygen-adding treatment mode

the pressure difference of boiler was remarkably reduced

the iron content in condensate maintaining within 10~20 μg/L;the ability of powdered resin filter for desalting and eliminating CO2 is poor;it is better to keep using the mixed bed in summer

and the desuperheating of air cooling condenser by spraying should be strengthed

to lessen the influence of temperature upon the anionic exchange resin.It is better to evaluate the corrosion situation of air coolled condenser via DHACL corrosion index determination method

according to the daily monitoring data of iron content in condensate water.