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How the degassing unit works

    • 159 posts
    June 23, 2022 9:44 PM EDT

    Refining applied in Ingot degassing unit

    Spinning Nozzle Inert Flotation (SNIF) – inert gas flotation through a rotating purge device. The main components of the SNIF P140UНВ secondary Ingot Degassing Machine.

    The main components of the installation of the degassing unit

    SNIF installation works on the principle of blowing process gas, usually argon, through rotating graphite units, the number of which can be from one to four, depending on the design and installation.

    The rotation of the purge assembly in conjunction with a continuous supply of argon creates a large number of gas bubbles that are completely distributed in the volume of the aluminum melt, thereby creating a “reactor with good mixing.” When argon bubbles float, the hydrogen dissolved in aluminum is desorbed into rising bubbles and removed from the melt.

    When a small amount of chlorine (typically less than 0.5% of the process gas flow) is added to the process gas, non-wettable non-metallic inclusions are separated from aluminum, attached to a degassing unit, and float to the surface. Chlorine also reacts with dissolved alkali metals (Na, Li, Ca, and K) to form chlorides that float to the surface and pass into slag. The Na content in the 5xxx series in the AMg3do “SNIF” alloy is 0.0006%, after 0.0003% – 0.0002%, that is, the Na content decreases by 2 or more times. Non-metallic particles and salts are then removed from the SNIF system.