Control method of blast furnace smelting of raw material with high zn load

Abstract

The invention discloses a method for controlling the blast furnace smelting of a high-Zn load raw material, and solves the problem of influence of serious bonding of a refractory furnace body on the stable and high-yield running of a blast furnace during the blast furnace smelting of the high-Zn load raw material. According to the method, the Zn load of the blast furnace is controlled to be greater than 0.15 kg / t and lower than 1.1 kg / t, and methods of distribution regime and air inlet area control, cooling water temperature control, furnace fluorite-washing and the like are combined, so that the problem of bonding of the refractory furnace body during smelting is solved, and the stable, high-yield and low-cost running of the blast furnace is ensured.

Description

technical field [0001] The invention relates to a blast furnace smelting process, in particular to a control method for high Zn load raw material blast furnace smelting. Background technique [0002] In recent years, the domestic iron and steel industry has entered an era of meager profits or even losses. In order to reduce costs, the ironmaking systems of various enterprises have increased the use of low-priced ore and low-grade ore. These raw material ores contain Zn, which has led to a sharp increase in the Zn load of blast furnaces and Large changes have seriously affected blast furnace production. [0003] The guiding opinion for the design of blast furnace ironmaking is to require that the Zn load of the blast furnace should not exceed 0.15kg / t, but under this standard, it is almost difficult to meet the above requirements when inputting low-cost high Zn load raw materials into the blast furnace during smelting. Considering the cost of raw materials, iron and steel en...

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Problems solved by technology

[0005] 1. A high Zn load can easily lead to an increase in the cyclic enrichment of Zn in the blast furnace, forming stubborn furnace body bonding of the blast furnace, resulting in adverse effects such as disordered gas flow distribution, low air volume, and material collapse and suspension. It is difficult to maintain a stable and smooth movement, and the economic and technical indicators of the blast furnace have declined

[0006] 2. The long-term air volume caused by the obstinate sticking of the blast furnace body is too small, which will easily lead to poor activity of the hearth, poor circulation of molten iron, further deterioration of the furnace condition, and high damage rate of the tuyere and the second set of equipment

[0007] 3. Zn has a low melting point and is gasified in the high-temperature area of ​​the lower part of the blast furnace. It penetrates into the tuyere refractory brick and expands after condensation, which affects the life of refractory materials such as brick lining, thereby affecting the longevity of the blast furnace

[0008] Based on the above problems, it can be seen that the most important impact brought by the high Zn load is the increase in the cyclic enrichment of Zn, resulting in the sticking of the blast furnace body, which makes the furnace type difficult to control, the furnace condition is unstable, and the output decreases. , the energy consumption increases, and will affect a series of problems such as the longevity of the blast furnace

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