Co-recycling method of aluminum oxide red mud and semi-dry desulfurized fly ash

Abstract

The invention belongs to the field of resource regeneration, and particularly relates to a co-recycling method for aluminum oxide red mud and semi-dry desulfurization ash. Compared with desulfurized gypsum, the semi-dry desulfurized fly ash has a high free alkali content, more complex components and unstable properties. First, aluminum oxide red mud and semi-dry desulfurized fly ash are mixed according to a mass ratio of 1: (0.03-1.95), the mixture is pelletized, pellets are dried, the pellets and pulverized coal (or coke powder) are mixed according to a mass ratio of 1: (0.03-0.95), and oxidation sintering is carried out. After cooling, the sintered ore is crushed and finely ground to 0.028mm-13.5mm through roller type crushing equipment and rod milling equipment, and calcium ferrite andgypsum are selectively dissociated. Firstly, magnetic separation is carried out under the conditions that the magnetic separation field intensity is 500 Gs-2100 Gs and the ore pulp concentration is 15%-99.99% to separate out calcium ferrite. The tailings are used for producing a cementing material to replace cement; or a gypsum product is separated from the tailings by using a micro-pulse elutriation jigger, and jigging tailings are filtered. The filter residue is used as a concrete admixture, filtrate is returned to a micro-pulse elutriation jigging process, soluble salt is circularly enriched, and then sodium chloride and potassium chloride are produced by processes such as a cold crystallization direct flotation method.

Description

Technical field [0001] The invention belongs to the field of renewable resources and relates to a co-resource method for alumina red mud and semi-dry desulfurization ash. Background technique [0002] Alumina red mud and semi-dry desulfurization ash are strongly alkaline solid wastes discharged by the alumina industry and the metallurgical industry respectively, which are difficult to dispose of. However, it contains a variety of valuable components and has a high comprehensive utilization value. At the same time, the production process of calcium ferrite is complex and has many applications in the steel, chemical and electronic industries. Gypsum is also a common building material. Both materials are used in large amounts and have high requirements on the quality of raw materials. Using alumina red mud and semi-dry desulfurization ash as raw materials, the unstable sulfite and residual quicklime in the semi-dry desulfurization ash can be fully utilized to participate in the si...

AI Technical Summary

Problems solved by technology

[0025] In summary, the above methods all involve the use of red mud and desulfurized gypsum / desulfurized ash to produce various special materials and fertilizers, but only desulfurized gypsum or gypsum components in desulfurized ash can be used, and unstable components in desulfurized ash cannot be used such as quicklime and calcium sulfite

The content of free alkali in semi-dry desulfurization ash is higher and its properties are more unstable. The existing technology has not been able to use the complementary properties between alumina red mud and semi-dry desulfurization ash to design more reasonable end products.

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