Because the water goes through different process in cyclic system of water and steam of power plant, the water quality often have bigger difference. Therefore, according to the needs of practical convenience, coal-fired power plants often give the water with a different name, is briefly described as follows. 

Raw Water: Raw water is untreated water source water, such as water from river, lake  and groundwater, etc. 

Make-up water The treated raw water  used for making up the water lost in cyclic system of steam and water  the processing is called make-up water for boiler. According to the different methods in purification treatment, the treated water is divided into softened water and dimineralized water, etc. The steam turbine condensate: The water formed by the condensed steam that has worked in steam turbine is known as condensate of steam turbine, which is briefly referred to as the condensate. 

Water drained: The steam condensate in steam pipelines and steam consuming equipment is collected to the drain tank or incorporated into the condensate system via the steam trap, this part of water is known as the water drained.

Condensed water returned: The steam condensate recovered after the heat is supplied from the thermal power plant  to the user is called condensed water returned,  which is divided into condensed water from the heating network heater and condensed water returned from production. 

Water supply The water is all kinds of equipment is the water supplied to the equipment, in thermal power plant, the water supplied to the boiler system is called feed water .The feed water from coal-fired power plant of condensed gas is composed of steam turbine condensate, make-up water and various water drained. The feed water of thermal power plant also includes the condensate returned. 

Boiler water The water flowing in the evaporation system of boiler proper is  known as the boiler water. 

Cooling Water The water used for cooling medium is called as cooling water. In coal-fired power plant, the main cooling water is the water through the condenser and used for cooling the exhaust steam of steam turbine. 

The water used for making up the circulating cooling water system is known as make-up water. 

Demineralized water: It refers to the water that salts (mainly strong electrolyte soluble in water) in it is removed or reduced to a certain extent. （zjl）