Preparation method of composite iron-carbon sintered ore and blast furnace smelting process

Abstract

The invention discloses a preparation method of a composite iron-carbon sintered ore. The preparation method comprises the following steps of 1) proportioning and uniformly mixing, namely proportioning iron ore and coal, adding a flux into the proportioning, and mixing the proportioned materials to obtain a sintering mixture; 2) granulating, namely granulating and pelletizing the sintered mixtureto obtain sintered green pellets; and 3) microwave sintering, namely distributing the sintered green pellets, performing microwave sintering, decomposing and volatilizing volatile matters and crystalwater in the sintered green pellets, and crushing and recrystallizing fixed carbon particles in the iron ore and the coal to obtain a high-strength composite iron-carbon sintered ore which has the effects of the sintered ore, pellet ore and coke and is a high-quality blast furnace burden. According to the preparation method of the composite iron-carbon sintered ore, microwave heating sintering isadopted, so that fixed carbon in coal is not reacted in the sintering process, the iron ore and particles of the fixed carbon are crushed and recrystallized, the high-strength high-quality composite iron-carbon sintered ore is prepared, the production efficiency of a blast furnace is improved, and the dependence of the blast furnace on the coke is relieved.

Description

technical field [0001] The invention relates to the preparation and application of composite sintered ore, in particular to a preparation method of composite iron-carbon sintered ore and a blast furnace ironmaking process, belonging to the technical field of ironmaking raw material production. Background technique [0002] Blast furnace ironmaking is an important link in steel production. This method is developed and improved from ancient shaft furnace ironmaking. Although many new ironmaking methods have been researched and developed by various countries in the world, due to the good technical and economic indicators of blast furnace ironmaking, simple process, large production volume, high labor productivity and low energy consumption, the iron produced by this method still accounts for the total iron production in the world. More than 95% of. [0003] At present, the most widely used blast furnace top charging system in blast furnace ironmaking is the blast furnace bell...

AI Technical Summary

Problems solved by technology

However, the charge is accompanied by particle segregation during the above operation process, which will directly or indirectly affect the distribution of the charge in the blast furnace

Among them, the segregation behavior of the charge particles during the belt feeding process will affect the particle distribution in the tank when the furnace roof is combined and filled, making the particle size distribution in the two tanks more uneven; , due to the special structure of the cans, the furnace charge enters the two tanks with different material flow trajectories and landing positions, causing the charge to form different particle size segregation structures in the two tanks. The distribution will have an important impact, which will eventually lead to fluctuations in the gas flow distribution in the furnace, which is not conducive to the production of the blast furnace

[0004] Based on the research background of the blast furnace bellless tank top charging system, in the process of using the belt conveyor for loading and tank loading, the particle segregation of the mineral material is serious during the process of belt conveying and tank filling, which leads to segregation of the subsequent chute distribution Seriously, the distribution of gas in the furnace is uneven, the utilization rate is low, the smelting coke ratio is increased, the effective volume utilization coefficient of the blast furnace is reduced, and it is not conducive to the full oxidation and reduction of iron ore in the blast furnace, that is, the recovery of Fe in iron ore and Stability of furnace condition

Particle size segregation on the feeding belt will make the distribution of particles more uneven in the tank, and during the process of filling the tank, the particles will easily form different particle size segregation structures in the two tanks, which will cause the distribution of the furnace charge in the subsequent tank cutting. Fluctuations, which in turn cause fluctuations in the gas in the furnace, affecting the stability of the blast furnace

In addition, because the blast furnace production process relies too much on coke, it not only causes a shortage of coke resources, but also seriously pollutes the environment during the coking process, which is not conducive to the sustainable development of blast furnace production

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