Blast-furnace smelting method for vanadium titano-magnetite

Abstract

The invention discloses a blast-furnace smelting method for vanadium titano-magnetite. The method is realized in a way that: vanadium titano-magnetite accounts for 30-60% of ferrous burden which is fed into a blast furnace, and the burden comprises 40-65% of agglomerate, 30-50% of pellet and 5-10% of lump ore; the diacidic basicities CaO / SiO2 of agglomerate, pellet and blast-furnace slag are respectively controlled at 1.6-2.5, 0.6-1.0 and 1.05-1.20; the content of MgO in blast-furnace slag is controlled at 7.5-9.0%; by adding two batches of ore and three batches of coke and using the charging operation of the development center, manganese oxide ore or sintered manganese ore powder, and fluorite are incorporated into injection coal and injected into the blast furnace along with the coal powder; and thus, the content of MnO in the slag and the content of CaF2 in the slag are respectively controlled at 1.0-4.5% and 0.50-2.0%, and the oxygen-enrichment percentage of the blast furnace is controlled at 2.0-4.0%. Compared with the smelting blast furnace using the same quality and structure of the burden, the comprehensive coke ratio of the invention is reduced by 20-50kg per ton of iron, the content of TFe in the slag is reduced by 50%, and the comprehensive cost per ton of iron is reduced by 30-50 yuan. The invention has wide prospects for popularization and application.

Description

technical field [0001] The invention relates to a blast furnace smelting method of vanadium-titanium-magnetite, in particular to a production method using high-proportion vanadium-titanium-magnetite blast furnace smelting production. Background technique [0002] As microalloying elements, vanadium and titanium can improve and improve the properties of steel for the steel industry, as catalysts for the chemical industry, and as alloying elements for the aerospace industry. Therefore, vanadium and titanium are indispensable and important metal elements for modern industries. Vanadium-titanium-magnetite is a variety of valuable metal associated iron ore, its reserves are very huge, and it is the main raw material for extracting valuable elements such as vanadium and titanium. [0003] At present, the smelting of vanadium-titanium magnetite mainly adopts the following process, one is to pass the vanadium-titanium magnetite through binary alkalinity CaO / SiO 2 The sintered ore i...

AI Technical Summary

Problems solved by technology

This method is currently a relatively mature industrial production process for vanadium-titanium magnetite. It has the advantages of large-scale production on existing conventional blast furnaces, no need for new equipment investment, and relatively mature production technology. However, this method has the following disadvantages : 1) Using this method of smelting, in order to improve the desulfurization effect of slag, it is usually used to increase the content of MgO in sinter to reduce the melting temperature of blast furnace slag, to achieve the purpose of improving the fluidity of slag and to use high alkalinity sinter to improve the slag Alkalinity, to achieve the purpose of increasing the sulfur capacity of the slag. Due to the increase in the basicity of the sintered ore, the solvent content increases, resulting in a decrease in the iron grade of the sintered ore, which greatly increases the amount of blast furnace slag produced per ton of iron, thereby increasing the consumption of coke per ton of iron 2) TiO in slag 2 The content is relatively high, and in a strong reducing atmosphere, TiO 2 It will reduce Ti and enter the slag to form TiC or TiN high-melting carbonitrides with C or N, resulting in an increase in the melting point of the slag, an increase in the melting temperature, and a thickening of the slag, resulting in a decrease in the desulfurization ability of the slag and a high sulfur content in the molten iron. At the same time, iron slag is difficult to separate, resulting in increased iron loss

Compared with traditional blast furnace smelting, this method can save the coking and sintering process, shorten the iron and steel manufacturing process, especially without using the increasingly tight coking coal resources and reduce sintering and coking pollutants and greenhouse gas CO 2 emissions, but this method has the following disadvantages: 1) the equipment investment per unit product is large, and the operating cost is high; 2) the production efficiency is not high, and the annual output of a single production line is low, generally below 150,000 tons; 3) in the melting process of conventional electric furnaces The selective reduction and oxidation kinetics of vanadium, titanium and iron are worse than those of the converter, the production cycle is long, and the energy consumption is relatively high. Under the current energy and raw material price system, the competitiveness is not strong