CN-122029296-A - Method for producing manganese carbide and method for producing manganese-containing steel

Abstract

The invention provides a method for manufacturing manganese carbide capable of reducing CO 2 emission. The manganese ore is heated to a treatment temperature at which the manganese ore is not molten, and is brought into contact with a mixed gas of hydrogen gas and a hydrocarbon gas at atmospheric pressure, whereby the reduction treatment of the manganese ore is performed. The partial pressure of the hydrocarbon gas in the mixed gas is preferably 10.0kPa or more, and the number of hydrogen atoms in the mixed gas is preferably 12 times or more the number of carbon atoms, and the treatment temperature is preferably set to a range of 800 ℃ or more and less than the melting temperature T m . The manganese ore is preferably treated with a rotary kiln by adjusting the particle size of the manganese ore to 3mm or more and 100mm or less, and the hydrocarbon gas or the like is preferably supplied from a position in the rotary kiln at a temperature of 700 ℃ or more. A method for producing a manganese-containing steel, which comprises a step of adding the obtained manganese carbide to molten steel.

Inventors

• YOSHIDA HIRONORI
• NAKAI YOSHIE

Assignees

• 杰富意钢铁株式会社

Dates

Publication Date

20260512

Application Date

20240809

Priority Date

20231102

Claims (9)

1. 1. A method for producing manganese carbide, wherein manganese ore is heated to a treatment temperature at which the manganese ore is not molten, and the manganese ore is subjected to reduction-carbonization treatment by contacting the manganese ore with a mixed gas of hydrogen gas and a hydrocarbon gas at atmospheric pressure.
2. 2. The method for producing a manganese carbide according to claim 1, wherein the partial pressure of the hydrocarbon gas in the mixed gas is set to 10.0kPa or more, and the number of hydrogen atoms in the mixed gas is set to 12 times or more the number of carbon atoms.
3. 3. The method for producing a manganese carbide according to claim 1 or 2, wherein the treatment temperature is set in a range of 800 ℃ or higher and lower than a melting temperature T m .
4. 4. The method for producing a manganese carbide according to any one of claims 1 to 3, wherein the particle size of the manganese ore is adjusted to 3mm or more and 100mm or less in advance.
5. 5. The method for producing a manganese carbide according to claim 4, wherein said reduction-carbonization treatment is performed by a rotary kiln.
6. 6. The method for producing a manganese carbide according to claim 5, wherein the mixed gas is supplied from a position where the temperature inside the rotary kiln is 700 ℃ or higher.
7. 7. The method for producing a manganese carbide according to claim 6, wherein the partial pressure of the hydrocarbon gas in the mixed gas is made 10.0kPa or more and the number of hydrogen atoms in the mixed gas is made 12 times or more the number of carbon atoms at the position where the mixed gas is supplied.
8. 8. The method for producing a manganese carbide according to any one of claims 5 to 7, wherein the maximum temperature in the interior of the rotary kiln is set in a range of 800 ℃ or higher and lower than a melting temperature T m .
9. 9. A method for producing a manganese-containing steel, comprising the step of adding the manganese carbide produced by the production method according to any one of claims 1 to 8 to molten steel.

Description

Method for producing manganese carbide and method for producing manganese-containing steel Technical Field The present invention relates to a method for producing manganese carbide by subjecting manganese ore to reduction-carbonization treatment, and to a method for producing manganese-containing steel using the produced manganese carbide. [ Definition ] In the present specification, the chemical formula of the material is expressed by letters such as "Mn", "MnO 2", and the chemical formula of the material is expressed by "manganese" and a non-abbreviated form, and manganese contained in the material is expressed regardless of the form. In the present specification, the unit "L" of volume indicates 10 -3m3, and the symbol "N" before the unit of volume of gas indicates a standard state of gas. The standard state means that the temperature is 0 ℃ and the atmospheric pressure is 1atm. In addition, the unit 1atm of pressure is 1.0135X10 5 Pa. In addition, t.mn (total Mn) in a substance represents the total amount of manganese content in the substance regardless of the morphology. Background Manganese contained in steel is added to molten steel in a steelmaking process in order to improve toughness and wear resistance of the steel. Examples of the manganese-containing substances added in the steel-making process include manganese metal, ferromanganese, and silicomanganese. Regarding ferromanganese, it is generally produced by charging a melting furnace with manganese ore, iron ore and a reducing agent, and melt-reducing the manganese ore and the iron ore. In such a method, in order to process a high-temperature melt, a transport vessel for storing and transporting the melt and a casting apparatus for cooling and solidifying the melt are required. Therefore, there is a concern that the device is enlarged and the handling property of the ferromanganese product is deteriorated. Further, there is a concern that the product yield is reduced due to scattering of the melt during the reduction treatment and the residue in the melting furnace. As a method for reducing manganese ore in a solid state, for example, as shown in patent documents 1 to 4, a method for performing a heat treatment using a reducing gas instead of a solid carbonaceous material has been proposed. Prior art literature Patent literature Patent document 1 Japanese patent laid-open No. 50-070202 Patent document 2 Japanese patent laid-open No. 56-072150 Patent document 3 Japanese patent laid-open No. 08-253308 Patent document 4 Japanese patent application laid-open No. 2023-140706 Disclosure of Invention Problems to be solved by the invention However, the above-described conventional techniques have the following problems to be solved. That is, in the methods disclosed in patent documents 1 and 2, manganese oxide (MnO 2、Mn2O3, etc.) having a high oxidation degree contained in manganese ore is partially reduced, and only manganese oxide (MnO) having a low oxidation degree is obtained. In order to obtain a manganese alloy product, the reduced product needs to be further reduced by melting. On the other hand, in the smelting reduction treatment of manganese ores, solid carbonaceous materials such as coke are used as a reducing agent, and thus a large amount of CO 2 is discharged in the above treatment. From the viewpoint of recent greenhouse gas reduction for global environmental protection, it is also necessary to reduce the amount of solid carbonaceous materials used in the production of manganese alloys, thereby reducing the CO 2 emissions. However, in the methods disclosed in patent documents 1 and 2, a manganese alloy product cannot be obtained using only a reducing gas, and it is necessary to supply a solid carbonaceous material when the product after reduction is further melt-reduced. Therefore, the reduction of the CO 2 emissions in the whole reduction treatment of ores is limited. In addition, in the methods disclosed in patent documents 3 and 4, manganese oxides having a high degree of oxidation contained in manganese ores are reduced to obtain manganese carbides (Mn 7C3、Mn3 C and the like). However, in the method disclosed in patent document 3, a step of finely pulverizing manganese ore to 1mm or less is required. In the case of such fine particles or powder, there is a concern that the handleability is deteriorated and the yield of the manganese carbide obtained after the treatment is lowered. In the method disclosed in patent document 4, an appropriate range of the particle size of the manganese ore is not disclosed, and similarly, in the case of fine particles or powder, there is a concern that the handleability is deteriorated and the yield of the manganese carbide obtained after the treatment is lowered. On the other hand, if the particle diameter is too large, there is a concern that the reaction efficiency of the reduction-carbonization treatment may be lowered. Further, the reduction-carbonization reaction of the manganese ore proceeds mo