Aluminum Molten Online Degassing Units

Aluminum Molten Online Degassing Units

Under the R&D technical support on Advanced Ceramics & Refractory of our Group, the Online Degassing Unit gets a long service life which adopts advanced High Silicon Melting Technology, Silicon Nitride Degassing Rotors, NSiC Heater Protection Tubes, and Thermocouple Protection Tubes etc., the Unit powering the high-precision aluminum manufacturing.

Online degassing unit shall be installed between furnace and casting equipment. It is used for hydrogen (H) and slags removal from molten aluminum. The Unit has dual functions: processing and heating. It serves high precision molten aluminum purification industry.

Standard Sizes of Degassing Unit

Max Degassing

Flow MT/H

15 MT/H35 MT/H65 MT/H
Degassing Box Size1 room 1rotor


2 room 2rotor


3 room 3rotor


Degassing Box Structure1 draining outlet &

1 deslagging outlet

2 draining outlet &

1 deslagging outlet

3 draining outlet &

1 deslagging outlet

Lifting SystemHoisting typeRotor mechanical liftingHydraulic lifting

Degassing Chamber Sizes & Capacity

Standard specifications

of degassing box

Interior size (mm)Melt retention capacity (kg)Melt flow rate (kg/min)
1 room 1 rotor(1B1R)685*685700150
1 room 1 rotor(1B1R)850*8501000200
2 room 2 rotor(2B2R)650*6501300250
2 room 2 rotor(2B2R)750*7501700350
2 room 2 rotor(2B2R)850*8502100450
3 room 3 rotor(3B3R)650*6502000360
3 room 3 rotor(3B3R)750*7502650500
3 room 3 rotor(3B3R)850*8503100750

Note: Molten aluminum will be remained in the degassing chamber for 3-5 minutes as standard design.

Online Degassing Unit Performance:

It is mainly used for the hydrogen (H) and slags removal from molten aluminum.

It takes gas flotation principle. The rotor takes inert gas or mixture of chlorine and inert gas into molten aluminum and smash the gas into dispersed tiny bubbles, the bubbles rise to molten aluminum surface and finish the below stated procedures at the same time: H is being absorbed in bubbles and is being removed; The chloride is removed (formed by chemical action with alkali metal and chlorine gas); Remove slags.

1The design standards of degassing efficiency

Average Degassing efficiency is 60%. If use Ar and Mg content ≤1%, thr efficiency can reach 0.09cc/100g.

2The design standards of lining structure

Lining is made of high silicon molten material, average working life is 2-3 years. It is featured non stick aluminum, no contamination. There is a float stopper inside to prevent oxides being drawn into molten aluminum and the bubbles or slags running out.

3The design  standards of rotor

It is made of Si3N4. Working life is 2-5 years. It performances well in corrosion resistance, heat shock resistance, oxidative resistance, abrasive resistance, mechanical strength. Shaft diameter 60mm, head diameter 200mm, which shall reduce resistance in stirring. Speed design 450-550 R/M will crush bubbles and disperse evenly into aluminum. It is cost effective during long time usage.

4Intrusive heater protection thimble

It is made from SiN, Average service life is 1-2years, featured high heating efficiency, oxidation and slagging prevention, no contaminations.

5The gas protection design

Ar mix of N2 and chlorine is available, protection method is also designed.

6Sealing structure design

The sealing structure include cover, lining, inlet and outlet to prevent slag and improve degassing efficiency.

Online degassing unit service life:

The whole unit except wearing parts≥5 years.

Assembling of Online Degassing unit:

Mechanical Drive

Degassing Box &Cover

Rotor &Heater

Electric Control


Switch off the heating unit after degassing box heating completed. Guide inert gas into rotor and release molten aluminum into the box when the heater temperature is closed to molten aluminum temperature.

Check the sealing between inlet/outlet and launder.

Check the cone located in heat protection draining in the bottom.

Check the molten aluminum temperature (min 720°C). Make the height of molten aluminum which be away from launder bottom at 3cm for observing the molten aluminum going into the box.

Operator shall wear protection clothes to close the cover. The slag on surface can be skimmed through the deslagging outlet when the molten aluminum flows into the box.

Start production when temperature up to 780°C. Close deslagging outlet for heating preservation.

Molten aluminum can be retained in the box with setting temperature during the heat preservation phase but with no molten aluminum handling.

Guide inert gases into the rotor to prevent air outlet blocking by molten aluminum.

Switch on the heater as soon as molten aluminum flow into the box completed and set heat preservation parameters.

Starting the heating system, control the temperature of the molten aluminum, monitor the gas flow rate, the speed of the rotor is changed from the heat preservation stage to the processing stage. At the same time, the inert gas flow into the rotor increases and the gas flow rate is changed from the preservation stage to the processing stage.

Operator sets molten aluminum heating temperature, maintain a stable degassing working condition.