Method of coproducing aluminium oxide, white carbon black and low ash carbon by coal gangue ecological utilization

Abstract

The present invention relates to a method for coproducing alumina, white carbon black and low-ash carbon. Said method is characterized by that it uses the minerals of coal gangue and kaolinite containing different S:O2 and Al2O3 contents as raw material, and makes said raw material be undergone the processes of breaking, beating to make extraction by using sulfuric acid solution and separation so as to obtain aluminium sulfate solution, in the course of extraction and separation small quantity of fluoride as activating agent can be added, then the sulfate as cocrystallization agent is added in said solution, then the above-mentioned material is undergone the processes of concentration and crystallization so as to obtain high-grade alum salt crystal, at the same time the acid mother liquor can be circularly utilized to make next extraction, the residuum can be extracted by alkaline liquor to obtain silicon oxide and recover carbon. Said invention is simple, and the extraction rate of alumina is high, the high-grade aluminium salt can be easily obtained.

Description

technical field

[0001] The invention relates to a method for extracting alumina and its by-products from coal gangue, in particular to a method for co-producing alumina, white carbon black, and low-ash carbon through the ecological utilization of coal gangue. Background technique

[0002] Coal gangue, referred to as gangue for short, is a kind of hard black rock with low carbon content that is associated with coal seams during the coal formation process, and becomes waste in the coal production process. Coal gangue is the industrial waste with the largest annual emission and accumulated accumulation in my country. In the process of coal production, the discharge of coal gangue accounts for about 10% of coal production. The annual discharge of coal gangue in my country is about 200 million tons, accounting for about 40% of the total industrial solid waste in the country. There are still more than 1,500 coal gangue hills in the country, accumulatively stockpiling 3.4 billion ...

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