The core working principle of the deaerator is based on Henry's Law and Dalton's Law of Partial Pressures. By heating the water and creating an environment conducive to gas release, it removes dissolved oxygen and other gases (such as nitrogen, carbon dioxide, etc.) from the water, preventing oxygen corrosion in equipment like boilers and pipelines.

The specific work process can be divided into the following steps:

1. Heating the water reduces the solubility of gases (application of Henry's Law)

Henry's Law states that at a given temperature, the solubility of a gas in water is directly proportional to the partial pressure of that gas above the water surface. The deaerator heats the feedwater to the saturation temperature at the corresponding pressure (e.g., a normal pressure deaerator is heated to 100℃) by introducing superheated steam (usually boiler exhaust or extracted steam). As the water temperature rises, the partial pressure of water vapor above the surface increases, while the partial pressures of dissolved gases like oxygen and nitrogen decrease accordingly. This results in a sharp drop in their solubility in water, causing the gases originally dissolved in the water to continuously escape.

2. Create an environment for thorough gas-liquid contact, accelerating gas release

The deaerator is internally equipped with a rotating film separator, a spray grill, and a filling layer, which disperses the feedwater in a film-like, droplet-like, or rain-like manner, thereby increasing the contact area and time between water and steam.

The Rotating Membrane Section: Water passes through the rotating membrane device to form a spiral water film skirt, which contacts the heating steam countercurrently, quickly heating up to the saturation temperature. Most dissolved gases are released at this stage (primary deoxygenation).

Filling Section / Spraying Section: Water treated in the rotating membrane section continues to fall, disperses into fine droplets through the spraying grate, then flows through the heat storage filling layer, where it comes into full contact with steam. This process further releases the remaining trace amounts of dissolved gases (deep oxygen removal).

3. Eliminate escaped gases, maintain low gas partial pressure (application of Dalton's Law of Partial Pressures)

Dalton's Law of Partial Pressures states that the total pressure of a mixture of gases equals the sum of the partial pressures of the individual components. The deaerator is equipped with an exhaust port at the top, where oxygen, nitrogen, and some steam escape and mix, being continuously expelled. This maintains the total pressure of the gases above the water surface in the deaerator close to the partial pressure of water vapor, keeping the partial pressure of dissolved gases extremely low, thus preventing the gases from re-dissolving into the water. This ensures that the oxygen content of the make-up water is reduced to the qualified standard (typically ≤7 μg/L).

Additional Information: The principles of different types of deaerators vary.

Atmospheric Deaerator: Heats water to 100℃ under atmospheric pressure, utilizing the atmospheric environment for auxiliary exhaust, with a simple structure, suitable for medium and low-pressure boilers.

High-Pressure Deaerator: Operates at pressures of 0.3~0.8MPa, offering higher saturation temperatures (133~175℃) and enhanced deaeration efficiency, suitable for high-pressure and ultra-high-pressure boilers.

Vacuum Oxygen Remover: By reducing the boiling point of water through vacuum extraction (can be used for deoxygenation at normal or low temperatures), it utilizes negative pressure to accelerate the release of gases, suitable for scenarios with specific water temperature requirements.