System and method for realizing aluminum ash resource utilization by plasma technology

Abstract

The invention provides a system and a method for realizing aluminum ash resource utilization by utilizing a plasma technology. The system comprises a pretreatment unit, a preheating feeding system, aplasma rotary kiln, a waste heat utilization unit, a tail gas purification unit, a carrier gas supply control system, an oxygen generation unit, a plasma torch and a purification unit. The method comprises the following steps that: aluminum ash is pretreated and preheated and then enters a plasma rotary kiln to be subjected to oxygen-enriched roasting, metal aluminum, aluminum nitride and aluminumcarbide in the aluminum ash are converted into aluminum oxide, fluoride salt and chlorate to volatilize; a calcined oxide is cooled, so that a low-purity aluminum oxide raw material can be obtained;the low-purity aluminum oxide raw material is purified through the purification unit, so that an aluminum oxide product can be obtained; tail gas of the plasma rotary kiln is subjected to heat exchange through the waste heat utilization unit and used for preheating the aluminum ash, and and therefore, energy consumption is reduced; the tail gas subjected to heat exchange is purified and then mixedwith oxygen to be recycled as carrier gas. According to the system and method, aluminum ash resource utilization is achieved, secondary environmental pollution caused by flue gas emission is avoided,and the economical efficiency and the environmental protection property are better.

Description

technical field [0001] The present application relates to the fields of aluminum industry and environmental protection, and specifically relates to a method and system for producing alumina materials through harmless treatment of secondary aluminum ash. Background technique [0002] Aluminum ash (aluminum slag) is produced in all aluminum melting processes such as aluminum electrolysis, aluminum processing, and recycled aluminum processing. Although the composition of aluminum ash varies slightly due to different raw materials and process conditions of various manufacturers, it usually contains metal aluminum, aluminum oxide, aluminum nitride, silicon dioxide, iron, silicon, magnesium oxides and potassium, sodium, Chlorides of metals such as calcium and magnesium, etc. Aluminum ash will produce ammonia, hydrogen and methane after contact with water, pollute the air, cause acute poisoning of close contacts, and easily cause fire. The entry of toxic metal elements in aluminu...

AI Technical Summary

Problems solved by technology

[0006] Aiming at the problems existing in the above-mentioned existing aluminum ash disposal and resource utilization technologies, the present invention provides a system and method for realizing resource utilization of aluminum ash by using plasma technology, using plasma technology to perform oxygen-enriched roasting on aluminum ash, and converting aluminum ash to Alumina material better solves the technical problems of complicated process and difficult industrial application in related technologies, and realizes the resource utilization of aluminum ash, which is beneficial to environmental protection

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