Thermal deaeration
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I would like to ask: Thermal deoxidation involves heating liquid water to a temperature at which the saturated vapor pressure above the liquid equals the pressure of water vapor; this causes any gases dissolved in the water to come out. So, what is this saturated vapor pressure?
I understand it this way: with the operating pressure of the deaerator remaining constant, as heating continues, more and more vapor will accumulate above the water surface, resulting in an increasing partial pressure of vapor. As a result, the partial pressures of other gases decrease. When the saturation temperature is reached, the water surface is entirely covered with vapor, and thus all other gases in the water are removed as well
Most thermal deaerators operate at atmospheric pressure; their main principle is to heat water containing oxygen to around 105°C. The solubility of oxygen in water will **decrease**, and oxygen will precipitate out. It mainly depends on temperature, not pressure
The deaeration temperature varies depending on the deaerator pressure; presumably, the higher the pressure, the higher the temperature.
That’s how it works; therefore, the steam inlet pressure for deaerators is generally around 0.02 MPa. The waste steam from the process can also be used for deaeration, as the dissolved oxygen level in water is lowest at a temperature of around 104 degrees.