Method for removing alkali metal via electrolytic aluminum liquid

Abstract

The invention discloses a method for removing alkali metal via electrolytic aluminum liquid. The method comprises the steps of: filling aluminum fluoride powder-mixed inert gas into the electrolytic aluminum liquid; and mixing the electrolytic aluminum liquid in the gas filling process, wherein the content of the aluminum fluoride powder is converted according to a detected concentration of alkali metal in the electrolytic aluminum liquid before the alkali removal treatment. The method provided by the invention has the following beneficial effect that the inert gas and the aluminum fluoride powder are used for removing the alkali metal, so that the alkali metal in the electrolytic aluminum liquid can be directly removed online, requirement that the content (5ppm) of the alkali metal of aluminum melt is better than the European related product standard is realized, the machining property requirements of high-grade, precision and advanced aluminum alloys can be realized, the purification requirements on high-quality aluminum melt by production of high-grade aluminum machining materials can be satisfied and the potential safety and environmental hazards in alkali metal removal by chlorine used by numerous enterprises at present can be avoided.

Description

technical field [0001] The invention relates to the technical field of aluminum melt purification treatment, in particular to a method for removing alkali metals in electrolytic aluminum liquid and an application of aluminum fluoride in electrolytic aluminum liquid to remove alkali metals. Background technique [0002] The main raw materials for aluminum electrolytic production include alumina, electrolyte, fluoride salt, cryolite, etc., so that the electrolytic aluminum solution will inevitably contain a large amount of alkali metals and alkaline earth metals such as sodium, magnesium, lithium, calcium, and non-metallic inclusions ( Mainly include aluminum chloride, electrolyte, fluoride salt, etc.). At present, the alkali metal content in the electrolytic aluminum solution produced by most aluminum electrolysis enterprises is as high as 40-80ppm. The high content of alkali metals will lead to the tendency of cracking in the casting process of aluminum alloy, which will reduc...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the invention is to solve the problem that the existing electrolytic aluminum liquid contains a large amount of alkali metal, and provide an electrolytic aluminum liquid that can directly remove the alkali metal in the electrolytic aluminum liquid on-line and realize the comprehensive purification of the aluminum melt before melting and casting Method for removing alkali metal and application of a kind of aluminum fluoride to remove alkali metal in electrolytic aluminum liquid