KR101163657B1 - Method of manufacturing pretreatment reduced briquette of manganese ore - Google Patents

Abstract

Disclosed is a method for producing prereduced briquettes of manganese light. The method for producing prereduced briquettes of manganese light according to the present invention comprises the steps of selecting a high specific manganese content from the manganese light, preparing a mixed molded body of the selected manganese content, and pre-reducing the mixed molded body Include. The preliminary reduction briquette according to the present invention can be used as a raw material for the production of metal manganese, and can be utilized for the production of high-grade steel and special steel by adding manganese required for steel in electric furnaces, induction furnaces, and the like.

Description

METHOD OF MANUFACTURING PRETREATMENT REDUCED BRIQUETTE OF MANGANESE ORE}

The present invention relates to a method of producing manganese briquettes, and more particularly, to a method of preparing pretreated reduced briquettes of manganese ore.

In order to utilize manganese ore in the production of steel materials, generally, ferroalloy steel is used to produce ferrous manganese alloy iron and use it in molten steel.

Iron manganese has a melting point of about 1,220 ℃ and is composed of manganese, iron composite carbide and β-Mn3C at room temperature and has a disadvantage in that the manufacturing cost is very high because it is expensive to manufacture and use it directly in molten steel.

Meanwhile, as a method for improving the recovery rate in the steelmaking process, briquettes are prepared by powder of a composition containing less than 30% of silicon oxide (SiO ₂ ) and less than 5% of alumina (Al ₂ O ₃ ) by weight in manganese ore. Techniques for introducing into the steelmaking process have been disclosed.

In the above method, when used in an electric furnace, an electric furnace, or an induction melting furnace in an oxide state with a very small amount of metal manganese (Mn), the slag layer is included as an upper slag layer, thereby increasing the volume of slag and containing manganese in molten steel. As the ratio is reduced, there is a disadvantage in that the effect of manganese-containing ferroalloy in molten steel is small.

The present invention has been devised to solve the above problems, and an object of the present invention is to provide a method for preparing prereduced briquettes of manganese light by screening high-weight manganese content from manganese light and pre-reducing after forming a mixed molded product of manganese light. It is done.

Method for producing a pre-reduced briquette of manganese light according to a preferred embodiment of the present invention for achieving the above object comprises the steps of selecting a high specific manganese content from the manganese light, preparing a mixed molded body of the selected manganese content, And pre-reducing the mixed compact.

The sorting of the manganese content is characterized in that the manganese light is shredded to 10 mesh (2 mm) or less and the high specific manganese content is separated from the manganese light by air separation due to specific gravity difference.

In addition, the step of preparing a mixed molded body of the manganese-containing content, the step of blending 5% by weight to 15% by weight of the bituminous coal in the high-weight manganese content, blast furnace slag in the high-weight manganese content in which the bituminous coal is blended Blending 2% to 5% by weight, and blending 4% to 7% by weight of bentonite as a binder to the high specific gravity manganese content in which the blast furnace slag is blended to form a molded body.

In addition, the step of pre-reduction of the mixed molded body, characterized in that for reducing the mixed molded body in a heating furnace in the temperature range of 1,150 ℃ ~ 1,380 ℃.

As described above, the pre-reduced briquettes of manganese light prepared by the present invention can be used as a raw material for the manufacture of metal manganese and can be utilized in the production of high-grade steel and special steel by adding manganese required for steel in electric furnaces, induction furnaces, etc. It is possible.

In addition, by using pre-reduced briquettes, it is possible to add useful manganese to steel without adding expensive manganese, which is useful for the production of manganese-containing steels and to reduce the cost of manufacturing manganese and iron manganese. Can be.

1 is a schematic process flowchart of a method of manufacturing pre-reduced briquettes of manganese light according to the present invention.
2 is a view showing the manganese metallization rate according to the blending amount of bituminous coal in the production of pre-reduced briquettes according to the present invention.
3 is a view showing the manganese metallization rate according to the blending amount of blast furnace slag in the production of pre-reduced briquette according to the present invention.
4 is a view showing a change in strength of the mixed molded body according to the content of bentonite used as a binder in the production of pre-reduced briquettes according to the present invention.
5 is a view showing the manganese metallization rate according to the temperature in the reduction furnace in the production of pre-reduced briquettes according to the present invention.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be embodied in various different forms, and the present embodiments merely make the disclosure of the present invention complete, and are common in the art to which the present invention pertains. It is provided to fully inform those skilled in the art of the scope of the invention, which is to be defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

Hereinafter, a method of manufacturing pre-reduced briquettes of manganese light according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail to avoid unnecessarily obscuring the subject matter of the present invention.

1 is a process flow chart for explaining the process of the manufacturing method of pre-reduced briquette of manganese light according to the present invention.

According to a preferred embodiment of the present invention, a method for preparing pre-reduced manganese briquettes comprises the steps of selecting manganese containing a high specific gravity from manganese light, preparing a mixed molded body of the selected manganese containing, and the mixed molded body. Pre-reducing.

In the step of selecting a high specific manganese content from the manganese light, first, the raw stone of the manganese light is pulverized using a mill.

The pulverized manganese light is separated by using an automatic screen, and the like to sort through the fraction based on the standard mesh 10mesh and to separate the specific gravity by using air, thereby separating the high and low specific gravity materials.

In the present invention, the manganese crushed light of 10% or more of the manganese of the crushed manganese light is used as a raw material of the preliminary briquettes.

The step of preparing a mixed molded body of manganese-containing comprises first mixing the high specific gravity manganese-containing coal in the range of 5% by weight to 15% by weight.

The step of preparing a mixed molded body of the manganese-containing includes the step of blending the blast furnace slag in the range of 2% to 5% by weight to the manganese-containing blended bituminous coal.

In addition, the step of preparing a mixed molded body of the manganese-containing includes forming a molded body to mix 4% to 7% by weight of bentonite as a binder in the manganese-containing manganese-containing compounded blast furnace slag.

Preferred compositions of manganese ore, bituminous coal, blast furnace slag powder and bentonite used in the preparation of the pre-reduced briquettes according to the present invention are shown in Table 1 below.

ingredient SiO ₂ Al ₂ O ₃ Fe ₂ O ₃ Mn MgO CaO Na ₂ O + K ₂ O C + H S Manganese
(weight%) 3.21-15.3 0.5-4.2 0.5-7.5 43.1-52.6 0.1-3.5 4.1-15.6 0.02-0.12 0.1-2.5 0.1 or less Bituminous coal
(weight%) 2.1-5.8 3.1-5.5 0.1-1.2 0.01-0.1 0.1-0.3 0.02-0.07 0.01-
0.02 84.5-93.2 0.3-
1.2 Blast furnace slag
(weight%) 32-35 10.5-12.5 0.2-0.5 0.01-1.2 6.1-7.5 40.5-43.5 0.5-1.5 - 0.6-0.8 Bentonite
(weight%) 67.3-69.9 11.9-15.2 0.92-2.01 0.01-0.1 0.6-
1.18 1.21-2.96 5.31-
13.2 - -

The bituminous coal containing the mixed compact of manganese light is used as a raw material for reducing the oxide state. The hydrogen and carbon component of the coal is reacted with the oxide to reduce some of the manganese metal by the following reaction formulas (1), (2) and (3) in the mixed molded body consisting of manganese oxide.

Mn O _x + H ₂ → Mn O _{x -1} + H ₂ O -------- (1)

Mn O _x + C → Mn O _{x -2} + CO ₂ --------(2)

Mn O _x + CO → Mn O _{x -1} + CO ₂ -------- (3)

By the reaction, the oxides of MnO, Mn ₃ O ₄ , Mn ₂ O ₃ are reduced to manganese metal.

The reduction to the manganese metal is different depending on the oxygen partial pressure of the reduction reactor, in order to remove the oxygen partial pressure, the coal is more than the amount used in the actual reduction reaction to contribute to the reduction.

The blending amount of bituminous coal used in the preparation of the mixed compact of manganese light is preferably in the range of 5% by weight to 15% by weight.

This is because when the compounding quantity of bituminous coal exceeds 15% by weight, the amount of impurities contained in the reduced manganese and the metal is increased, the volume is large, and excess carbon is contained.

In addition, when the blending amount of the bituminous coal is less than 5% by weight, the amount to be reduced during the reduction reaction is insufficient to produce a reduced manganese of 65% or more, which is because the reduction effect is not exhibited.

In order to maintain the proper reduction of manganese ore, bituminous coal has a close relationship and is also directly related to the partial pressure of oxygen in the reduction furnace.

Therefore, it is important to mix | blend so that the amount of carbon required for reduction may be satisfied, without adding excess bituminous coal.

Instead of the bituminous coal used in the present invention, it is also possible to use coke dust and coke pulverized powder generated in the coke production process.

The coke dust is the main component is residual carbon from which the chemical component is dehydrogenated into a powdery coke state generated in the process of producing coal-coke by drying coal for use in blast furnace in the steelmaking process.

In the present invention, the blast furnace slag may be included in the preparation of the mixed molded body of manganese light. Blast furnace slag is to produce a molten iron to be a low melting point in the furnace and serves to promote the reduction of manganese light.

The content of the blast furnace slag is preferably from 2% by weight to 8% by weight, and less than 2% by weight does not promote reduction, and when it exceeds 8% by weight, the reducing effect is saturated and there is no effect difference compared to 8% by weight. Because.

In addition, since the basicity of SiO ₂ and Al ₂ O ₃ and CaO and MgO contained in the blast furnace slag and the bituminous coal reconstituted material is controlled, the reduction reaction of the metal component contained in the manganese oxide is facilitated by low melting point. Can be.

Bentonite may be used as a binder to prepare the mixed molded article of manganese light, and the bentonite is preferably mixed in an amount of 4% by weight to 7% by weight in order to increase binding force.

This is because when the content of bentonite is less than 4% by weight, the molding strength is weak, and when it is 7% by weight or more, overmolding occurs.

In addition, the alkali metal oxide contained in the bentonite may contribute to the reducing effect during the reduction treatment.

That is, the bentonite acts as a physical binder, but the non-crosslinked oxygen crosslinked oxygen forming a network structure of an oxide such as SiO ₂ during the reduction reaction of the alkali component (Na ₂ O + K ₂ O) among the chemical components in the bentonite. A phenomenon in which the melting point is lowered by forming an open structure is shown.

This is mainly alkali and alkaline earth metal oxides, and in the present invention, it reacts with manganese oxides to lower the melting point, thereby contributing to the reduction of manganese oxide and other metals contained in the mixed molding (bricket) and inducing solid phase reaction of low melting point. To promote reduction.

The mixed compact of the high specific gravity manganese content, bituminous coal, blast furnace slag and bentonite is made into briquettes under pressure.

The mixed molded body of the briquette manganese content is pre-reduced in a reduction reactor to be prepared as a pre-reduced briquette of manganese light.

In this case, the temperature of the reduction reactor is preferably 1,150 ℃ ~ 1,380 ℃ temperature range is cooled after reduction.

Hereinafter, embodiments of the prereduced briquettes of manganese light according to the present invention will be described in detail.

≪ Example 1 >

Example 1 of the present invention is to obtain an appropriate blending content of bituminous coal in manganese crushed ore, and add bituminous charcoal to manganese crushed ore in the same ratio as in Table 2 below, and then add 5% of the binder, and then pressurized briquettes. Reduced iron was prepared as in the process shown in FIG.

At the time of reduction, the reducing atmosphere was maintained, and the temperature of the heating furnace was reduced for 90 minutes at 1,150 ° C.

division Comparative Example 1 Inventory 1 Inventory 2 Inventory 3 Honorable 4 Comparative Example 2 Manganese crushed light (g) 97 95 92.5 90 85 80 Bituminous coal (g) 3 5 7.5 10 15 20 weight% 3 5 7.5 10 15 20

The total amount of manganese and metal manganese were measured by wet chemical analysis of the briquettes prepared as described above.

Manganese Metallization (%) = (Metal Mn in Briquette) / (Total Mn in Briquette) * 100 (%)

In this case, it calculated except the ash component of bituminous coal.

The results are shown in FIG. 2, by which the quality of the actual pre-reduced manganese steel can be determined, some of which are not reduced to manganese and some of which have been reduced.

As a result, it was judged as a pretreatment step to select a partial reduction condition, and if the manganese metallization rate is 50% or more, 50% or more of the present invention Examples 1-3 and Comparative Example 2 of FIG. The metallization rate was less than 50%, which is due to the lack of the amount of bituminous carbon, which is insufficient to reduce the amount of carbon necessary for the reduction.

In addition, Comparative Example 2 exhibits a sufficient metallization rate, but it is not preferable because the carbon content in the pre-manganese ore due to the content of excess bituminous coal does not increase the proportion of the relative metal amount.

Therefore, in this invention, it is understood that the ratio which mix | blends 5 weight%-15 weight% of bituminous coal and 85 weight%-95 weight% of manganese crushed minerals is an appropriate mix | blending.

<Example 2>

Example 2 of the present invention is 2 to 6% by weight of the blast furnace slag to the sample which was mixed under the conditions of the invention example 3 of the bituminous coal and manganese crushed ore (90% crushed, 10% bituminous coal) by the method treated in Example 1 Samples were mixed by 1% by weight in intervals up to 5% of the binder bentonite as in Example 1 to prepare a sample by pressing briquette molding, and maintaining a reducing atmosphere at the time of reduction, the temperature of the furnace at 1,150 ℃ Reduction reaction was carried out for 90 minutes.

As a result, the manganese metallization rate was measured and shown in FIG.

As shown in FIG. 3, the manganese metallization rate is increased by adding blast furnace slag.

When the content of the blast furnace slag is less than 2% by weight, the manganese metallization rate is small and was found not to increase even in the case of more than 5% by weight.

Therefore, it can be seen that the addition of blast furnace slag of 2% by weight to 5% by weight in the present invention is preferable for improving the metallization rate and pretreatment.

<Example 3>

In the present embodiment, the strength of the binder was improved by reducing the amount of powder generated during the reduction treatment to improve the production yield.

3% by weight of blast furnace slag was added to the sample blended with the conditions of 3 (pulverized light 90%, bituminous coal 10%) and bentonite as a binder was added from 3% by weight to 8% by weight. .

The measurement results of the compressive strength are shown in FIG. 4.

As shown in Figure 4, it can be seen that the compressive strength after pressing increases as the content of bentonite increases.

In the present invention, it can be seen that the content of bentonite for maintaining a moderate strength of 50kgf / cm ² or more is preferably 4% to 7% by weight.

Bentonite, which is the binder, contains a large amount of alkali and alkaline earth components, thereby lowering the melting temperature, thereby promoting a reduction reaction, and contributing to the manganese metallization rate. It is an important ingredient.

<Example 4>

In the embodiment of the present invention, as the composition of briquettes for pretreatment, 3% by weight of blast furnace slag was added to the sample prepared under the conditions of Inventive Example 3 (90% of crushed light and 10% of coal briquettes), and 5% of bentonite as a binder. Compressive strength after pressure molding was measured by adding up to%.

The temperature of the heat treatment is reduced to 90 minutes at 1,100 ℃, 1,150 ℃, 1,200 ℃ and 1,250 ℃, and then cooled and heat treated the briquettes by measuring the total amount of manganese and metal manganese through wet chemical analysis. The percentage of manganese metallization (%) was calculated based on the amount of.

Manganese Metallization (%) = (Metal Mn in Briquette) / (Total Mn in Briquette) * 100 (%)

The ash component of bituminous coal included in the ash was calculated.

The results are shown in FIG.

As shown in FIG. 5, depending on the heat treatment temperature, the metallization rate is different and the range of 1,150 ° C. to 1,380 ° C. becomes a preferable heat treatment temperature condition of the present invention.

That is, in the present invention, a preliminary reduction treatment briquette is prepared by reduction heat treatment at least 1,150 ℃.

On the other hand, during the reduction heat treatment, it is preferable to treat the metal material and the temperature before melting the slag material such as CaO, Al ₂ O ₃ , SiO ₂ and the like, which is reduced when the briquette product of the present invention has a melting point or higher. The problem that the melt is attached to the process equipment at the time of treatment to solidify occurs to remove the problem occurs, the upper limit of the heat treatment temperature is preferably 1380 ℃ or less.

Pre-reduced briquettes prepared by the present invention can be used as a raw material for the production of metal manganese, and can be utilized for the production of high-grade steel and special steel by adding manganese required in steel in electric furnaces and induction furnaces, and pre-reduced briquettes By using, it is possible to add effective manganese to steel without adding expensive manganese.

In addition, the manufacturing method of the present invention can be expected to be useful for the production of manganese-containing steel and to reduce the cost of manufacturing metal manganese and iron manganese.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, You will understand.

It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is shown by the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. .

S10: Selection step of manganese light S20: Step of preparing mixed molded body
S30: pre-reduction step of mixed molding

Claims (4)

Selecting a high specific manganese content from the manganese light;
Preparing a mixed molding of the selected manganese contents; And
Pre-reducing the mixed compact,
Selecting the manganese content,
The manganese light is crushed to 10 mesh (2mm) or less, characterized in that to separate the high specific manganese content from the manganese light by air separation due to specific gravity difference,
Preparing a mixed molded body of the manganese content,
Blending 5 wt% to 15 wt% of the bituminous carbon in the high specific manganese content;
Blending 2% by weight to 5% by weight of blast furnace slag to the high specific gravity manganese content blended with the bituminous coal; And
And mixing 4 wt% to 7 wt% of bentonite as a binder in the high specific gravity manganese content in which the blast furnace slag is blended to form a molded body.
Method for preparing prereduced briquettes of manganese ore. delete delete The method of claim 1,
Pre-reducing the mixed molding,
The mixed compact is reduced in a heating furnace in the temperature range of 1,150 ℃ ~ 1,380 ℃ in a reducing atmosphere characterized in that the manufacturing method of pre-reduced briquettes of manganese light.

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