A thermal deaerator is used for reducing the oxygen content of brume boiler feedwater. Without proper treatment, feedwater for brume boilers generally has a high oxygen content of 8-10mg/I, which causes crital erosion in the system.

Theory of operation
The condensate and the make-up water are mixed so that a temperature of 60-70 °C is reached before conducted to the top of the deaerator. In the top of the deaerator the water is wracked, so the feasts can escape the subcaste that surrounds every single water patch.