KR900005431B1 - Process for mixing sintered materials - Google Patents

Abstract

Method for producing mixing material for sintering is characterised by preparing the mixing solution of 0.6-1.5 wt.% limestone and 6 wt.% water before mixing sintering materials, and sprinkling the mixed sintering materials with the above solution in granulating process.

Description

Mixing method of water and quicklime when mixing sintered raw materials

1 is a graph showing the relationship between air permeability and sintering time according to the addition of quicklime.

2 is a graph showing the relationship between room temperature intensity and low temperature reduction differentiation according to the addition of quicklime.

In the present invention, in the manufacture of sintered ore, the mixing of water and quicklime in the mixing of sintered raw materials to improve the properties of the sintered ore by improving the breathability in the sintered layer and promoting the production of calcium-ferrites, artificial products during the sintering process It relates to a method of addition.

In general, sintered ore is manufactured by mixing appropriate coke with iron ore and raw materials such as quicklime, serpentine, silica sand and limestone, adding about 6% water, and mixing uniformly in a drum-mixer. Make a change. In this way, uniformly mixed and granulated compounding material is charged into the sintering system, and the surface of the compounding material is ignited in the ignition furnace for about 2 minutes. Then, the air is sucked from the suction duct below the sintering machine. Sintering reaction advances by combustion and a sintered ore is manufactured.

At this time, the maximum temperature in the sintered layer is elevated to 1300-1400 ℃, and the sintered ore is crushed to 5-50mm suitable for the blast furnace charging conditions, less than 5mm is reused as semi-glossy. On the other hand, the granulated compound raw material collapses when ignited in the ignition furnace, and the air permeability in the sintered layer is poor, which is a factor that adversely affects the sinterability. Therefore, conventionally, there is a method of adding quicklime to secure air permeability in the sintered layer in the sintered blended material, and at the same time, a method of improving the activity of quicklime by adding hot water. However, there was a problem of segregation distribution of quicklime in the blended raw materials due to the mixing of the blended raw material and quicklime due to the moisture in the blended material, the nonuniformity of the mixed raw material and the non-uniform agglomeration of the quicklime when spraying.

The effect mechanism of quicklime added to improve breathability in the sintered layer is that Ca ⁺⁺ in quicklime is uniformly distributed in the adhesion of pseudoparticles and changes to Ca (OH) ₂ of microcrystalline below 1μmm, and binds well with raw particles Filling the gap between atomic particles promotes granulation. In addition, fine Ca (OH) ₂ promotes the production of artificial mineral calcium-ferrite during the sintering process, thereby improving room temperature strength and low temperature reduction differentiation. Therefore, in the present invention, unlike the conventional method of adding and mixing quicklime to the blended raw material and then sprinkling water, the mixture is preliminarily mixed with the quicklime and the mixed solution is sprayed on the blended raw material, so that the air permeability of the sintered ore, room temperature strength and It is to improve the low temperature reduction differentiation.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The present invention, in the method of mixing water and quicklime in the sintering raw material blending in order to manufacture a sintered ore, the quick-mixing of the quicklime which is a sintered blending raw material to 0.6-1.5% by weight with respect to 6% by weight of water to assemble the mixed solution The present invention relates to a method of mixing water and quicklime when mixing raw materials for sintering raw materials, characterized by uniform watering.

Hereinafter, the present invention will be described in detail through examples.

Example 1

To prepare a sintered ore by the conventional method and the present invention as shown in Table 2 to the blended raw material prepared as shown in Table 1, the ignition temperature: 1,200 ℃, ignition time: 2 minutes, negative pressure: -1000mmH ₂ O, basicity : 1.65 and coke: A sintering pot experiment was carried out under conditions of 3.4% and the results are shown in FIGS. 1 and 2. Table 3 below shows the chemical components of the blended raw materials.

TABLE 1

TABLE 2

TABLE 3

As can be seen from FIG. 1 showing the relationship between the air permeability in the sintered layer and the sintering time, the inventive examples (4, 5, 6) have better air permeability in the sintered layer and shorter sintering time than the conventional example (1). And similar or superior to the conventional example (2). In addition, Figure 2 shows the relationship between the quality of the sintered ore, the room temperature intensity is 47.30, 48.90 in the prior art (1, 2), while the examples of the invention (4, 5, 6) was 49.01, 50.23 and 50.87 The low temperature reduction differentiation rate was 31.08 and 28.81 of the conventional examples (1, 2), whereas the methods (4, 5, 6) of the present invention were significantly improved to 29.02, 28.05 and 27.33.

As described above, in the present invention, the quicklime and water are mixed in advance, and the mixed solution is uniformly sprayed to distribute the quicklime evenly in the sintered blended material, and the bonding material of fine Ca (OH) _divalent sintered ore (bonding materals) By promoting the production of phosphorus calcium-ferrite uniformly, there is an effect of remarkably improving the room temperature strength, air permeability and low temperature reduction differentiation of the sintered ore.

Claims (1)

In the method of mixing water and quicklime when mixing sintered raw materials to prepare sintered ore, the quicklime, which is a sintered blended raw material, is mixed in advance at 0.6-1.5% by weight with respect to 6% by weight of water and uniformly sprayed when the mixed solution is assembled. Mixing method of water and quicklime when formulating a sintered raw material characterized in that.

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