Degassern

Degassern, or degasser, is an apparatus designed to remove dissolved gases from liquids, most commonly oxygen, carbon dioxide, and nitrogen. Degassers are used across industries to reduce corrosion, improve process control, and stabilize products. In metallurgy, degassing also refers to removing gases from molten metals to improve quality.

The basic principle is to reduce the amount of gas dissolved in a liquid. This can be achieved by lowering the partial pressure of the gas (vacuum degassing), increasing the liquid temperature (thermo-degasation), or sweeping the liquid with an inert gas such as nitrogen or argon (gas-stripping). Some systems combine heating with vacuum or inert-gas purging and may employ membranes or special contactors to enhance gas transfer.

Common types include vacuum degassers, which use reduced pressure to drive gas release; deaerators, often used for boiler feedwater, that heat the liquid and vent the evolved gases; and membrane or contactor-based degassers that separate gases through permeable barriers. In metallurgy, degassing of molten metals involves inert-gas bubbling to remove hydrogen, nitrogen, and other dissolved gases before solidification, often in a ladle furnace or tundish.

Applications span power generation, chemical processing, beverage and pharmaceutical manufacturing, water treatment, and metal production. In boiler and cooling-water systems, effective degassing minimizes corrosion and scaling. In steelmaking, high-purity degassed metal yields better ductility and reduced porosity. Design considerations include capacity, gas removal efficiency, material compatibility, energy consumption, and safety.