According to the principle of aluminum refining agent purification, the refining agent generates tiny gas bubbles through a chemical reaction in the aluminum melt. When these gas pools float up, hydrogen and non-metallic inclusions are taken out of the surface of the aluminum melt. At the same time, the non-metallic inclusions are wetted by the refining agent, so that the inclusions are adsorbed on the refining agent droplets and float together on the surface of the aluminum melt.
Aluminum Refining Agent Purification Characteristics
1. In addition to the role of the refining agent to absorb and dissolve hydrogen and inclusions, it is more important to produce compounds and gases that degas and remove slag through a certain reaction in the melt.
2. All chemical raw materials without hydrogen are selected to replace the traditional H-containing materials to avoid secondary pollution in the process of hydrogen removal.
3. Increase the number of purification bubbles, reduce the diameter of the purification bubbles, extend the floating distance of the bubbles in the molten aluminum, increase the residence time of the bubbles in the molten aluminum, that is, increase the time for the bubbles to process the molten aluminum, and the hydrogen removal effect will be more obvious.
4. The role of refining agent to remove slag highlights the refining ability of adsorption, dissolution and chemical reaction and the separation ability of slag lead, and the effect of high slag lead content is good.
5. Environmentally friendly materials are selected so that the main gases after the reaction are CO2, N2, etc., and the environmental pollution is small.
The purification process and control points of the gas refining agent are 99.99% pure nitrogen is used. The high-quality refining agent is blown into the bottom of the aluminum melt bath through the refining tank. The refining time is 20~30min, and the amount of refining agent is 1.5~2kg per ton of melt. The height of aluminum melt tumbling and splashing during blowing is generally 30-50mm, not more than 180mm. The temperature of the aluminum melt during refining is 710-740℃, and the scum on the surface of the aluminum melt is cleaned before and after refining.