The situation of using residential sewerage after treatment as circulatory cooling water in gangfiring thermal power plant of Datun Coal & Power Company in order to reduce water consumption has been presented. For discharged water from the sewerage treatment plant

if suspended matter in the said water is less than 20 mg/L

the discharged water can directly be used for circulatory cooling

otherwise

pretreatment as coagulation and settlement should be carried out. Other treatment measures

such as bactericide dosing

treatment for scaleretarding

gumball cleaning and ferroussulfate filmforming in condenser tubes etc.

have been taken as in common power plants. In consecutive two years after putting the said project into operation

the terminal temperature difference of condenser keeps lower than 5℃ in the whole year

satisfying fully the requirements of power plant

and retrieving the capital investments only in more than one year

having remarkable economic and environmental benefits.