High-mechanical strength carbon-containing pellets for blast furnace and production method for high-mechanical strength carbon-containing pellets

Abstract

The invention discloses high-mechanical strength carbon-containing pellets for a blast furnace. The pellets comprise the following raw materials in percentage by weight: 80 to 92 percent of magnetite concentrate, 1 to 2 percent of bentonite, 2 to 12 percent of coal dust, 2 to 14 percent of magnesium rock flour and 0.4 to 0.6 percent of MgO / SiO2 which is controlled in the raw materials. The production method for the pellets comprises the following steps of: weighing 80 to 92 percent of magnetite concentrate, 2 to 12 percent of coal dust, 1 to 2 percent of bentonite and 2 to 14 percent of magnesium rock flour according to a proportion and batching to ensure that 0.4 to 0.6 percent of MgO / SiO2 is contained in the mixed materials; spraying water, uniformly mixing, controlling the water content of the mixed materials to be 8 to 9 percent, and steaming for 30 to 60 minutes; preparing green pellets by using a pelletizing machine, screening the green pellets, and thus obtaining qualified screen pellets with the particle size of 9 to 16mm; and roasting at the temperature of between 1,250 and 1,300 DEG C for 10 to 15 minutes, and thus obtaining finished pellets with higher strength. By the method, the strength of the carbon-containing pellets is improved, the carbon-containing pellets with a certain metallization rate are obtained, and extremely high value for energy conservation and consumption reduction of the blast furnace is realized.

Description

technical field [0001] The invention belongs to the technical field of ironmaking raw material pellet ore agglomeration, in particular to a carbon-containing pellet with high mechanical strength for blast furnaces produced by using coal powder and MgO-containing materials and a production method thereof. Background technique [0002] Carbon-containing pellets are a kind of pellets that add a certain amount of carbonaceous reducing agent to themselves. Compared with traditional pellets, carbon-containing pellets can expand the carbon-oxygen reaction interface and reduce the diffusion of gas at the solid-phase reaction interface. Its own carbon and oxygen are in direct contact, and the gas is excluded from the inside out, which inhibits the oxidation of the oxidizing gas. Therefore, the production and application of carbon-containing pellets is one of the effective means for metallurgical enterprises to reduce the coke ratio. Existing studies have shown that iron entering the b...

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Problems solved by technology

[0006] The carbon-containing pellet production method described above mainly has the following problems: 1. the addition of carbon materials is high, and the produced carbon-containing pellets are similar to metallized pellets, which is not suitable for blast furnaces; 2. Production and preparation are carried out on the production process of balls, which increases production costs; ③ produced by traditional processes, the strength of finished balls is low, which cannot meet the requirements of blast furnaces

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