A green smelting method for recycled aluminum alloy

Abstract

The invention relates to the technical field of recycled aluminum, and provides a green smelting method for recycled aluminum alloy. After aluminum secondary resources obtained after paint removal aresmelted and subjected to component adjustment, argon refining and argon degassing are adopted at a certain temperature, argon is introduced into a recycled aluminum alloy melt, inclusions and hydrogen are brought out of the melt, and a recycled aluminum alloy melt with high purity and low hydrogen content is obtained; the argon is fine and dispersed argon bubbles when introduced; the argon introduction mode is one or two of introduction from air-permeable bricks at the bottom of a smelting furnace and introduction from an air guide pipe; and the average size of the bubbles during argon introduction is 0.5-20.0 mm. According to the method, salt refining agents and nitrogen degassing agents are not used, the nitrogen burning loss is avoided, generated aluminum slag does not contain pollutants such as salt and aluminum nitride, and the obtained recycled aluminum melt is low in hydrogen and inclusions content. The quality of a recycled aluminum product is good, the method is simple and effective, and the application prospect is wide.

Description

technical field [0001] The invention relates to the technical field of secondary aluminum, in particular to a green smelting method of secondary aluminum alloy. Background technique [0002] The demand for aluminum is growing rapidly, and bauxite is difficult to meet. At the same time, the secondary resources of aluminum are increasing rapidly. Using aluminum secondary resources as raw materials to regenerate aluminum alloys not only does not require bauxite, but also consumes only 3%-4% of primary aluminum per ton of aluminum, which has a remarkable effect in energy saving and emission reduction. [0003] Aluminum secondary resources have a wide range of sources, including metals (such as Mg, Si, Fe, Zn, etc.) and non-metals (paint, oil, carbon fiber, etc.) And other impurities exist in the melt. Therefore, the secondary aluminum alloy melt must be refined. The existing "salt impurity removal-nitrogen degassing" refining process has the following problems: ① salt flux is...

AI Technical Summary

Problems solved by technology

The existing "salt impurity removal-nitrogen degassing" refining process has the following problems: ① salt flux is used for refining, and the harmful white smoke pollution generated during the refining process contains Cl, F, etc.; Salt and other pollutants; ② Nitrogen is used for degassing. In the initial process, nitrogen will react with aluminum and its alloy elements such as Mg, and MgN and AlN are easily formed, resulting in difficult control of melt composition and low recovery rate

Although the method is simple and low-cost, nitrogen will react with molten aluminum to form aluminum nitride, making refining slag difficult to dispose of

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