According to the power of water or steam circulation, boilers can be divided into natural circulation boilers, forced circulation boilers, once-through boilers and combined circulation boilers.
In a boiler, energy from the fuel is transferred to liquid water in order to create steam. Once the water is heated to boiling point, it is vaporized and turned into saturated steam. When saturated steam is heated above boiling point, dry steam is created and all traces of moisture are erased. This is called superheated steam.
