The thermal deaerator (rotating film deaerator) is a new type of thermal deaeration unit that can remove dissolved oxygen and other gases from the water in the thermal system, preventing corrosion of thermal equipment and ensuring the safe operation of power plants and industrial boilers. The thermal deaerator is a new type of thermal deaerator, capable of operating at constant pressure, sliding pressure, and negative pressure, featuring high allowable dissolved oxygen content in the inlet water, low inlet water temperature, and large make-up water volume. It is suitable for deaeration of water used in power plant boilers, industrial boilers, and make-up water for thermal power plants.