Comprehensive utilization method for red mud

Abstract

The invention belongs to the technical field of comprehensive utilization of red mud. The technical proposal of the invention is that: adding coke, anthracite which is 7-75% of mass of red mud, calcium compound which is 0-16% or aluminiferous compounds which is 0-645% into the red mud, placing in an electrical furnace after mixing; melting to deoxidize at the temperature ranging from 1400 to 1800 DEG C, and keeping temperature for 0.5 to 4 hours, crushing the red mud for separation after naturally cooling. The main chemical ingredients of the red mud is that: SiO<2> is 10-23wt%, Fe<2>O<3> is 7-40wt%, Al<2>O<3> is 6-20wt%, CaO is 3-45 wt%, Mgo is 0.5-3 wt%, K<2>O is 0.1-0.4 wt%, Na<2>O is 2-11 wt%, TiO<2> is 1-6 wt%, cauterized loss is 8-12wt%. Under high temperature, SiO<2> and Fe<2>O<3> in the red mud of the invention are deoxidized into ferro-silicon alloy, Al<2>O<3> and CaO are generated to calcium aluminate, Na<2>O and K<2>O are volatilized at high temperature to be refined, cooled and deposited to obtain the calcium aluminate material and ferro-silicon alloy by crushing separation, so the invention has the characteristics of wide application range and high additional value.

Description

technical field [0001] The invention belongs to the technical field of comprehensive utilization of red mud. In particular, it relates to a method for preparing ferrosilicon alloy and calcium aluminate material by using electric smelting reduction red mud. Background technique [0002] Red mud is solid powdery waste discharged during the production process of alumina smelting industry. Generally, about 1.0-1.7 tons of red mud are produced for every ton of alumina produced. According to incomplete estimates, the world discharges about 60 million tons of red mud every year. my country is the world's fourth largest producer of alumina, and its accumulated red mud stockpile has reached 41 million tons. A large amount of red mud is stored in the open air, occupying farmland and hills, and the dust is flying, causing environmental and air pollution. The pH of red mud is very high, and its leachate is about 12.1 to 13.0. The lye in the red mud seeps into the formation with the r...

AI Technical Summary

Problems solved by technology

[0004] Research on the use of red mud to produce cement (Ren Dongmei, Mao Yanan. Comprehensive utilization of red mud [J]. Nonferrous Metal Industry, 2002, [5]: 57-58), due to the high alkali content of red mud, the ratio of red mud is affected by cement The restriction of alkali content limits the application of red mud as a raw material for cement production. The comprehensive utilization rate of red mud is only 35% to 50%, and the utilization rate is low.

[0005] Charcoal reduction of iron in red mud, the method of recovery by magnetic separation process (Liao Chunfa, Jiang Guoping. Technology research on iron recovery from red mud. China Mining. Volume 16 No. 2. February 2007), but due to A large amount of SiO in red mud 2 , Al 2 o 3 , CaO and other substances are not fully utilized, and the cost is high, the utilization rate is low, and it is difficult to realize the comprehensive utilization of red mud