A smelting method with iron ore added

Abstract

The invention discloses a smelting method with added iron ore, comprising the following steps: (1) placing the iron ore in a crusher for crushing treatment, and then placing the iron ore in a ball mill for grinding to obtain ore powder; (2) preparing quartz sand and manganese monoxide into quartz sand fine powder and manganese monoxide fine powder respectively, and preparing coal powder into fine powder; (3) pouring the ore powder, quartz sand fine powder, manganese monoxide fine powder, coal powder fine powder and titanium dioxide into a mixer and stirring them evenly, and placing the stirred materials in a ball-making plate for ball-making; (4) placing the ball-shaped materials in a gas-based vertical furnace to obtain direct reduced iron; (5) placing the direct reduced iron in an electric furnace, and obtaining primary molten steel through heating, oxygen blowing and slag-making operations; (6) placing the primary molten steel in a refining furnace for refining; and (7) starting argon blowing at the bottom of the ladle while adding a slag-making agent and a deoxidizer in the refining furnace; the process flow is greatly simplified, the consumption of raw fuel, auxiliary materials, electricity and the like is reduced, emissions are reduced, and labor costs are reduced.

Description

Technical Field

[0001] The invention relates to the field of steelmaking, and in particular to a smelting method with added iron ore. Background Art

[0002] The development direction and trend of steel materials are high-quality steel with high cleanliness, high uniformity, ultra-fine structure, high precision and high added value. Steel materials for high-end equipment are high-tech products and are key basic materials required for industries such as aerospace, energy and transportation, marine engineering, automobile lightweighting, environmental protection, and major equipment manufacturing, major engineering construction, emerging industries and advanced national defense weapons. Summary of the invention

[0003] The purpose of the invention is to provide a high-quality steel smelting process.

[0004] The present invention solves the technical problem by adopting the following technical solution: a smelting method with added iron ore, characterized in that it comprises the following steps:

[0005] (1) placing iron ore in a crusher for crushing to obtain iron ore powder, screening the iron ore powder through a screening machine to screen out iron ore powder with a particle size of less than 20 mm, and then grinding the iron ore powder in a ball mill to obtain ore powder with a particle size of less than 220 mesh;

[0006] (2) crushing and grinding quartz sand and manganese monoxide in sequence to obtain quartz sand fine powder and manganese monoxide fine powder, respectively, and grinding coal powder to obtain fine powder;

[0007] (3) pouring the ore powder obtained in step (1) and the quartz sand fine powder, manganese monoxide fine powder, coal powder fine powder and titanium dioxide in step (2) into a mixer and stirring them evenly, placing the stirred materials in a pelletizing plate for pelletizing;

[0008] (4) placing the spherical material obtained by pelletizing in step (3) in a gas-based vertical furnace, introducing a reducing gas into the gas-based vertical furnace for smelting for 3-6 hours to obtain direct reduced iron;

[0009] (5) placing the direct reduced iron obtained in step (4) in an electric furnace, and further removing carbon, sulfur, phosphorus and other elements in the direct reduced iron through heating, oxygen blowing and slag making operations to obtain primary molten steel;

[0010] (6) placing the primary molten steel obtained in step (5) in a refining furnace, and adding a slag-forming agent and a deoxidizing agent for refining when the process meets the following conditions:

[0011] The process conditions are that the temperature in the refining furnace ranges from 1650-1700°C;

[0012] (7) in step (6), while adding the slag-forming agent and the deoxidizing agent into the refining furnace, argon blowing is started from the bottom of the ladle to obtain high-purity molten steel;

[0013] (8) The high-purity molten steel obtained in step (7) is continuously cast through a continuous casting machine to obtain a steel billet.

[0014] Preferably, the particle size of the spherical material obtained by pelletizing the material in the pelletizing disk in step (3) is 10-15 mm.

[0015] Preferably, the reduction temperature in the gas-based vertical furnace in step (4) is in the range of 1600-1700°C.

[0016] Preferably, the refining time in step (6) is 30-50 min.

[0017] Preferably, the argon gas flow rate of the argon blowing in step (7) is 160-210m 3 / h, the argon blowing time is 3-4min, and the baking temperature range of the ladle bottom is 200-240℃.

[0018] Preferably, the weight ratio of the iron ore powder, quartz sand, manganese monoxide, titanium dioxide and coal powder is 1:0.08:0.03:0.02:0.1.

[0019] Preferably, the slag-forming agent is composed of lime, alumina and quartz sand in a weight ratio of 1:1:16.

[0020] The present invention has the following beneficial effects:

[0021] 1. The use of a vertical furnace for direct reduction of iron ore to produce reduced iron greatly simplifies the process flow, reduces the consumption of raw materials, fuel, auxiliary materials, electricity, etc., reduces emissions, and reduces labor costs.

[0022] 2. The molten steel is heated, slag-made, argon-blown and vacuum-degassed multiple times through a gas-based vertical furnace, an electric furnace and a refining furnace, effectively removing harmful elements such as sulfur, carbon and phosphorus from the molten steel, improving the purity of the molten steel, and thus obtaining high-quality steel billets.

[0023] 3. There are no requirements for the selection of iron ore, so the raw material selectivity is wider, which can fully improve the utilization rate of iron ore. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is further described below in conjunction with embodiments.

[0025] Example 1

[0026] This embodiment provides a smelting method with added iron ore, characterized in that it includes the following steps:

[0027] (1) placing iron ore in a crusher for crushing to obtain iron ore powder, screening the iron ore powder through a screening machine to screen out iron ore powder with a particle size of less than 20 mm, and then grinding the iron ore powder in a ball mill to obtain ore powder with a particle size of less than 220 mesh;

[0028] (2) crushing and grinding quartz sand and manganese monoxide in sequence to obtain quartz sand fine powder and manganese monoxide fine powder, respectively, and grinding coal powder to obtain fine powder;

[0029] (3) pouring the ore powder obtained in step (1) and the quartz sand fine powder, manganese monoxide fine powder, coal powder fine powder and titanium dioxide in step (2) into a mixer and stirring them evenly, placing the stirred materials in a ball-forming tray for ball-forming, and the particle size of the spherical materials obtained by ball-forming the materials in the ball-forming tray is 10 mm;

[0030] (4) placing the spherical material obtained by pelletizing in step (3) in a gas-based vertical furnace, introducing a reducing gas into the gas-based vertical furnace for smelting for 3 hours to obtain direct reduced iron, wherein the reduction temperature in the gas-based vertical furnace is 1600° C.;

[0031] (5) placing the direct reduced iron obtained in step (4) in an electric furnace, and further removing carbon, sulfur, phosphorus and other elements in the direct reduced iron through heating, oxygen blowing and slag making operations to obtain primary molten steel;

[0032] (6) placing the primary molten steel obtained in step (5) in a refining furnace, adding a slag-forming agent and a deoxidizing agent for refining when the process meets the following conditions, and the refining time is 30 min:

[0033] The process conditions are as follows: the temperature in the refining furnace is 1650°C;

[0034] (7) In step (6), argon blowing is started at the bottom of the ladle while adding slag-forming agent and deoxidizer to the refining furnace to obtain high-purity molten steel. The argon flow rate of the argon blowing is 160m 3 / h, argon blowing time is 3min, and the baking temperature range of the bottom of the ladle is 200℃;

[0035] (8) The high-purity molten steel obtained in step (7) is continuously cast through a continuous casting machine to obtain a steel billet.

[0036] In a more preferred embodiment, the weight ratio of the iron ore powder, quartz sand, manganese monoxide, titanium dioxide and coal powder is 1:0.08:0.03:0.02:0.1.

[0037] In a more preferred embodiment, the slag-forming agent is composed of lime, alumina and quartz sand in a weight ratio of 1:1:16.

[0038] Example 2

[0039] This embodiment provides a smelting method with added iron ore, characterized in that it includes the following steps:

[0040] (1) placing iron ore in a crusher for crushing to obtain iron ore powder, screening the iron ore powder through a screening machine to screen out iron ore powder with a particle size of less than 20 mm, and then grinding the iron ore powder in a ball mill to obtain ore powder with a particle size of less than 220 mesh;

[0041] (2) crushing and grinding quartz sand and manganese monoxide in sequence to obtain quartz sand fine powder and manganese monoxide fine powder, respectively, and grinding coal powder to obtain fine powder;

[0042] (3) pouring the ore powder obtained in step (1) and the quartz sand fine powder, manganese monoxide fine powder, coal powder fine powder and titanium dioxide in step (2) into a mixer and stirring them evenly, placing the stirred materials in a ball-forming tray for ball-forming, and the particle size of the spherical materials obtained by ball-forming the materials in the ball-forming tray is 15 mm;

[0043] (4) placing the spherical material obtained by pelletizing in step (3) in a gas-based vertical furnace, introducing a reducing gas into the gas-based vertical furnace for smelting for 6 hours to obtain direct reduced iron, wherein the reduction temperature in the gas-based vertical furnace is 1700° C.;

[0044] (5) placing the direct reduced iron obtained in step (4) in an electric furnace, and further removing carbon, sulfur, phosphorus and other elements in the direct reduced iron through heating, oxygen blowing and slag making operations to obtain primary molten steel;

[0045] (6) placing the primary molten steel obtained in step (5) in a refining furnace, adding a slag-forming agent and a deoxidizing agent for refining when the process meets the following conditions, and the refining time is 50 min:

[0046] The process conditions are as follows: the temperature in the refining furnace is 1700°C;

[0047] (7) In step (6), argon blowing is started at the bottom of the ladle while adding slag-forming agent and deoxidizer to the refining furnace to obtain high-purity molten steel. The argon flow rate of the argon blowing is 210m 3 / h, argon blowing time is 4min, and the baking temperature range of the ladle bottom is 240℃;

[0048] (8) The high-purity molten steel obtained in step (7) is continuously cast through a continuous casting machine to obtain a steel billet.

[0049] In a more preferred embodiment, the weight ratio of the iron ore powder, quartz sand, manganese monoxide, titanium dioxide and coal powder is 1:0.08:0.03:0.02:0.1.

[0050] In a more preferred embodiment, the slag-forming agent is composed of lime, alumina and quartz sand in a weight ratio of 1:1:16.

[0051] Example 3

[0052] This embodiment provides a smelting method with added iron ore, characterized in that it includes the following steps:

[0053] (1) placing iron ore in a crusher for crushing to obtain iron ore powder, screening the iron ore powder through a screening machine to screen out iron ore powder with a particle size of less than 20 mm, and then grinding the iron ore powder in a ball mill to obtain ore powder with a particle size of less than 220 mesh;

[0054] (2) crushing and grinding quartz sand and manganese monoxide in sequence to obtain quartz sand fine powder and manganese monoxide fine powder, respectively, and grinding coal powder to obtain fine powder;

[0055] (3) pouring the ore powder obtained in step (1) and the quartz sand fine powder, manganese monoxide fine powder, coal powder fine powder and titanium dioxide in step (2) into a mixer and stirring them evenly, placing the stirred materials in a ball-forming tray for ball-forming, and the particle size of the spherical materials obtained by ball-forming the materials in the ball-forming tray is 13 mm;

[0056] (4) placing the spherical material obtained by pelletizing in step (3) in a gas-based vertical furnace, introducing a reducing gas into the gas-based vertical furnace for smelting for 5 hours to obtain direct reduced iron, wherein the reduction temperature in the gas-based vertical furnace is 1650° C.;

[0057] (5) placing the direct reduced iron obtained in step (4) in an electric furnace, and further removing carbon, sulfur, phosphorus and other elements in the direct reduced iron through heating, oxygen blowing and slag making operations to obtain primary molten steel;

[0058] (6) placing the primary molten steel obtained in step (5) in a refining furnace, adding a slag-forming agent and a deoxidizing agent for refining when the process meets the following conditions, and the refining time is 30 min:

[0059] The process conditions are as follows: the temperature in the refining furnace is 1680°C;

[0060] (7) In step (6), argon blowing is started at the bottom of the ladle while adding slag-forming agent and deoxidizer to the refining furnace to obtain high-purity molten steel. The argon flow rate of the argon blowing is 180m 3 / h, argon blowing time is 3.5min, and the baking temperature range of the ladle bottom is 220℃;

[0061] (8) The high-purity molten steel obtained in step (7) is continuously cast through a continuous casting machine to obtain a steel billet.

[0062] In a more preferred embodiment, the weight ratio of the iron ore powder, quartz sand, manganese monoxide, titanium dioxide and coal powder is 1:0.08:0.03:0.02:0.1.

[0063] In a more preferred embodiment, the slag-forming agent is composed of lime, alumina and quartz sand in a weight ratio of 1:1:16.

[0064] The order of the above embodiments is only for the convenience of description and does not represent the advantages or disadvantages of the embodiments.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A smelting method with addition of iron ore, characterized in that: The following steps are involved: (1) placing iron ore in a crusher for crushing to obtain iron ore powder, screening the iron ore powder through a screening machine to screen out iron ore powder with a particle size of less than 20 mm, and then grinding the iron ore powder in a ball mill to obtain ore powder with a particle size of less than 220 mesh; (2) crushing and grinding quartz sand and manganese monoxide in sequence to obtain quartz sand fine powder and manganese monoxide fine powder, respectively, and grinding coal powder to obtain fine powder; (3) pouring the ore powder obtained in step (1) and the quartz sand fine powder, manganese monoxide fine powder, coal powder fine powder and titanium dioxide in step (2) into a mixer and stirring them evenly, placing the stirred materials in a pelletizing plate for pelletizing; The particle size of the spherical material obtained by pelletizing the material in the pelletizing plate is 10-15mm; The weight ratio of mineral powder, quartz sand, manganese monoxide, titanium dioxide and coal powder is 1:0.08:0.03:0.02:0.1; (4) placing the spherical material obtained by pelletizing in step (3) in a gas-based vertical furnace, introducing a reducing gas into the gas-based vertical furnace for smelting for 3-6 hours to obtain direct reduced iron; The reduction temperature in the gas-based vertical furnace ranges from 1600 to 1700°C; (5) placing the direct reduced iron obtained in step (4) in an electric furnace, and further removing carbon, sulfur and phosphorus from the direct reduced iron by heating, oxygen blowing and slag making operations to obtain primary molten steel; (6) placing the primary molten steel obtained in step (5) in a refining furnace, and adding a slag-forming agent and a deoxidizing agent for refining when the following process conditions are met: The process conditions are that the temperature in the refining furnace ranges from 1650-1700°C; The refining time is 30-50min; (7) in step (6), while adding the slag-forming agent and the deoxidizing agent into the refining furnace, argon blowing is started from the bottom of the ladle to obtain high-purity molten steel; The argon gas flow rate of argon blowing is 160-210m 3 / h, argon blowing time is 3-4min, and the baking temperature range of the bottom of the ladle is 200-240℃; (8) The high-purity molten steel obtained in step (7) is continuously cast through a continuous casting machine to obtain a steel billet.

2. The smelting method with added iron ore according to claim 1, characterized in that: The slag-making agent is composed of lime, alumina and quartz sand in a weight ratio of 1:1:16.