Process for extracting aluminium and chlorides in aluminium ash

Abstract

The invention relates to a method for extracting aluminium and chloride by processing aluminium ash. The method is suitable for the comprehensive application of the aluminium ash which is industrial residue generated during remelting and casting in an electrolytic aluminium plant, an aluminium processing plant or a secondary aluminium plant. The invention is characterized in that the extraction process comprises the following steps of: directly sending delivering extracted aluminium liquid for casting, after the aluminium ash is heated to completely melt aluminium in the aluminium ash and separate the aluminium from slag; immersing the slag in water to dissolve the chloride in the aluminium ash in the water, and separating solid and liquid; and evaporating liquid phase to produce a chloride crystal, and using solid phase as a raw material to produce alumina. The method for processing the aluminium ash has the advantages of short process flow, convenient operation, easy industrial implementation, high comprehensive application value and high coefficient of recovery, can extract various valuable compositions in the aluminium ash. The coefficient of recovery of the metal aluminium in the aluminium ash is larger than 85 percent, and the coefficient of recovery of the chloride in the aluminium ash is larger than 80 percent.

Description

A method for extracting aluminum and chloride in aluminum ash technical field The invention relates to a method for processing aluminum ash to extract aluminum and chloride, which is suitable for the comprehensive utilization of aluminum ash, the industrial waste slag produced in the remelting and casting process of electrolytic aluminum plants, aluminum processing plants and recycled aluminum plants. Background technique Aluminum ash is the slag and floating skin produced in the process of melting aluminum, aluminum ingots, and secondary aluminum smelting and refining aluminum. Aluminum ash is a large-volume and seriously polluting industrial waste, mainly from the casting of electrolytic aluminum plants and aluminum processing plants. process and the smelting and casting process of secondary aluminum plants. According to statistics, about 20-40 kg of aluminum ash is produced for each ton of raw aluminum processed. The amount produced is less when the aluminum liquid is d...

AI Technical Summary

Problems solved by technology

However, the above-mentioned technology has the following deficiencies: (1) the direct recovery of aluminum in the aluminum ash is not considered when recycling alumina, and the metal aluminum in the aluminum ash is returned to the process of extracting alumina, which wastes the alkali and energy consumption of dissolving aluminum (2) The recycling of chlorides in aluminum ash is not considered; (3) The process is complicated and economical