System and method for cooperatively processing secondary aluminum ash by virtue of cement kiln

Abstract

The invention provides a system and a method for cooperatively processing secondary aluminum ash by virtue of a cement kiln. The system comprises a waste residue preprocessing system, an anaerobic wet-grinding conversion system, an alkali metal salt leaching system and a cement kiln resourceful treatment system which are sequentially connected, wherein all equipment and connecting pipelines in thesystem are sealed, and a suction machine is arranged so as to generate a micro-negative pressure. The method comprises the following steps: (S1) secondary aluminum ash preprocessing, (S2) anaerobic wet-grinding conversion, (S3) alkali metal salt leaching, and (S4) cement kiln resourceful treatment. According to the system and the method, the harmless and resourceful final treatment of the secondary aluminum ash can be realized, 0.1t-0.3t of alkali metal salt, 0.02t-0.1t of caustic soda and 0.5t-0.8t of aluminum oxide byproducts can be extracted during the treatment of 1t of secondary aluminumash, and 0.2t-0.3t of cement raw materials and 0.05t-0.2t of a denitration agent can be provided for a cement plant. By utilizing an anaerobic wet-grinding conversion machine, H2 and CH4 generated inthe conversion process do not burn and explode, the disinfection and conversion of solid waste residue materials can be realized, and converted gas can be extracted.

Description

technical field [0001] The invention relates to a system and method for disposing of aluminum smelting industrial waste residue, in particular to a system and method for utilizing cement kiln to collaboratively resource-dispose secondary aluminum ash, and belongs to the technical field of aluminum smelting industrial waste residue recycling and reuse. Background technique [0002] Aluminum ash is insoluble matter and other impurities floating on the surface of aluminum melt during the production of electrolytic aluminum, cast aluminum and recycled aluminum. The aluminum ash released from the electrolytic aluminum factory is also called white aluminum ash. According to statistics, 1 ton of electrolytic aluminum produces about 30kg of white aluminum ash, which contains 20-70% of metallic aluminum. Generally, the aluminum ash is removed from the smelting furnace with an iron rake. After the molten aluminum is cooled, most of the metal aluminum can be recovered by grinding and g...

AI Technical Summary

Problems solved by technology

[0009] Judging from the relevant patented technology and research and development reports published so far, there are wet treatment methods and fire treatment methods for the disposal of secondary aluminum ash, among which wet treatment includes acidification and alkalization treatment, and then extracts valuable aluminum ash from waste residue. These disposal methods may have technical problems such as high energy consumption, large investment, high disposal cost and secondary pollution:

[0010] (1) There are fluorides in the secondary aluminum ash, no matter which method is used above, a large amount of HF gas may be produced, and its toxicity and corrosion will cause harm to people's lives and mechanical equipment

[0011] (2) Metal aluminum, AlN, Al in secondary aluminum ash 2 C 3 When in contact with water, NH will be produced 3 、H 2 、CH 4 , Improper disposal of these gases will not only pollute the environment, but may also cause explosion and combustion hazards

[0012] (3) After the secondary aluminum ash wet treatment, a large amount of waste water will be produced. There is a small amount of F-ion in the waste water, which still has the risk of polluting the environment.

[0013] (4) After the secondary aluminum ash extracts useful substances, there is still a large amount of solid waste residue, and there is still Cl - , F - Such highly toxic substances are difficult to treat as general solid waste. Even if general solid waste can be achieved, how to achieve the ultimate treatment of it is still a difficult problem

[0014] (5) A large amount of energy is required to dispose of secondary aluminum ash by calcination or to evaporate the brine solution. For the solution of leaching soluble aluminum salt by calcination with ammonium salt, not only the energy consumption is high in calcination and evaporative crystallization, but also it is impossible to prevent NH 4 F, NH 3 pollution to the environment

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