Production method and application of vanadium-containing low-alkalinity sintered ore

Abstract

The invention discloses a production method of vanadium-containing low-alkalinity sintered ore, which comprises the following steps of: S10, uniformly distributing various vanadium-containing iron powder, solid fuel and self return ore on a sintering machine trolley according to a certain proportion, and sintering the vanadium-containing iron powder into ore by adjusting sintering ignition, air draft and machine speed to obtain the sintered ore. The invention also discloses application of the sintered ore for vanadium extraction and steelmaking, the sintered ore produced by the invention changes the traditional production mode of vanadium extraction and steelmaking by using pellets, the vanadium extraction and steelmaking by replacing the pellets with the vanadium-containing low-alkalinity sintered ore is realized, the vanadium-containing level of molten steel can be further improved, and the production cost is more effectively reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of metallurgy, and in particular relates to a production method and application of a vanadium-containing low-basicity sintered ore. Background Art

[0002] In the steelmaking process, pellets are needed for vanadium extraction and steelmaking. At present, the pellets of a certain factory are all purchased from outside. On the one hand, the cost of purchasing pellets is high, and on the other hand, the V2O5 content of the pellets is low at about 0.42%, which increases the cost of the vanadium products produced and the V2O5 content is low. Especially at the time of high-quality development of the vanadium-titanium new materials industry, giving full play to the advantages of vanadium-titanium resources and fully realizing the vanadium extraction work of the whole system is an urgent problem to be solved. Therefore, it is urgent to find a material that can replace pellets. Summary of the invention

[0003] The present invention provides a production method and application of vanadium-containing low-basicity sintered ore. The produced sintered ore replaces pelletized ore. According to the preliminary sintering cup test data, the sintered ore produced by the sintering machine has a composition that satisfies the requirement of replacing pelletized ore for vanadium extraction and steelmaking, thereby achieving the purpose of improving the level of vanadium-containing materials entering the steelmaking furnace and reducing smelting costs.

[0004] The technical solution provided by the present invention is: A method for producing vanadium-containing low-basicity sintered ore comprises the following steps: S10, various vanadium-containing iron powders, solid fuels, and self-returned ore are evenly distributed on a sintering machine trolley according to a certain ratio, and the vanadium-containing iron powders are sintered into ore to obtain sintered ore by adjusting sintering ignition, exhaust and machine speed.

[0005] Preferably, in S1, the particle size of the sintered ore is 5 mm ≤ 40 mm, and the sintered ore is directly fed into the S2 converter silo; The particle size of the sintered ore is less than 5mm, and it is returned to the sintering machine for re-sintering; The sintered ore with particle size >40mm is crushed and screened to ≤40mm and ≥5mm and then put into S2 converter silo. The sintered ore with particle size less than 5mm is returned to the sintering machine for re-sintering.

[0006] Preferably, the chemical composition and mass percentage of the sintered ore are: TFe≥58%, V2O5≥0.50%, CaO≤2.4%, SiO2≤3.5%; binary basicity R≤0.69.

[0007] Preferably, the mass ratio of vanadium-containing iron powder, solid fuel and self-return ore in S1 is 73.5:6.5:20.

[0008] Preferably, the sintering ignition temperature in S1 is 1050±50°C; The exhaust air and machine speed are adjusted according to the sintering end point temperature and position. The sintering machine end point temperature is controlled to be ≥400℃, and the sintering end point position is controlled at the second to last wind box. The exhaust is achieved by adjusting the air door opening and frequency conversion of the main exhaust fan to provide air volume for the sintering process; The machine speed is used to adjust the speed of the main engine. The machine speed should not be adjusted more than 3 times per shift, and each adjustment should not exceed 0.1m / min.

[0009] Preferably, the moisture content of the vanadium-containing ferropowder in S1 is controlled to be ≤10%, and the chemical composition and mass percentage of the vanadium-containing ferropowder are: TFe≥63.5%, V2O5≥0.4%, SiO2≤5.0%, P≤0.075%, TiO2≤3.5%, Al2O3≤1.7%, S≤0.19%.

[0010] Preferably, the solid fuel in S1 includes sintered coal and coke powder, and the requirements for various indicators of sintered coal and coke powder are: particle size less than 3mm, volume percentage> 75%, low calorific value ≥ 21MJ / kg, moisture Mt ≤ 9.5%, fixed carbon FCad ≥ 72%, ash Ad ≤ 20%, volatile matter Vdaf ≤ 10%, sulfur S ≤ 1.0%; The mass ratio of sintered coal to coke powder is 2:1.

[0011] Preferably, the self-returned ore in S1 refers to sintered ore with a size of less than 5 mm after crushing and screening, and the chemical composition and mass percentage are: TFe≥58%, CaO≤2.4%, V2O5≥0.5%.

[0012] An application of a production method of vanadium-containing low-basicity sintered ore for vanadium extraction and steelmaking, the sintered ore vanadium extraction and steelmaking production method comprises the following steps: S11, inspecting the CaO content in the sintered ore, and calculating the amount of sintered ore added in the vanadium extraction and steelmaking production according to the CaO content; S12. The amount of sintered ore added calculated according to S11 is transported by truck to the converter silo for vanadium extraction and steelmaking.

[0013] Furthermore, the amount of sintered ore added in S11 is adjusted according to the CaO content in the sintered ore. When the CaO mass content in the sintered ore is greater than 6.4%, it will not meet the use requirements of the vanadium extraction converter. The specific addition amounts are as follows: (1) The mass percentage of CaO in the sintered ore is ≤2.4%, and the amount of sintered ore used for vanadium extraction and steelmaking is 40kg / t; (2) The mass percentage of CaO in the sintered ore is 2.4-2.8%, and the amount of sintered ore used for vanadium extraction and steelmaking is 30-40kg / t; (3) The mass percentage of CaO in the sintered ore is 2.8-3.7%, and the amount of sintered ore used for vanadium extraction and steelmaking is 20-30 kg / t; (4) The mass percentage of CaO in the sintered ore is 3.7-6.4%, and the amount of sintered ore used for vanadium extraction and steelmaking is 10-20kg / t.

[0014] The beneficial effects of the present invention are: The sintered ore of the present invention can replace the pelletized ore for vanadium extraction and steelmaking, which can further increase the vanadium content of molten steel and more effectively reduce the production cost.

[0015] The product of the present invention is sintered ore, which is easy to store, transport and obtain, and is convenient to add and the amount of addition is easy to control. The sintered ore has high iron and V2O5 content and extremely low CaO content. It participates in chemical reactions in the converter, which can increase the yield of other elements such as Fe and V and increase the vanadium content of molten steel.

[0016] The sintered ore of the present invention strictly controls the particle size, increases the V2O5 content, reduces the CaO content, is conducive to addition and reaction, and the particle size is ≤5mm. It is returned to the sintering machine bin and re-sintered to increase the vanadium content of the sintered ore. DETAILED DESCRIPTION

[0017] The present invention is further described in detail below in conjunction with specific implementation modes. Example 1

[0018] A 360㎡ sintering machine in a certain factory produces vanadium-containing low-basicity sintered ore. Its sintering ore distribution structure is based on the ratio of vanadium-containing iron powder, solid fuel, and self-returned ore in 73.5:6.5:20, which is evenly distributed on the sintering machine trolley through belt transportation and sintering distribution. The moisture content of vanadium-containing iron powder is controlled at 1.0%. The chemical composition and mass percentage of vanadium-containing iron powder are: TFe=61.45% (converted to Fe2O3=87.79%), V2O5=0.87%, SiO2=2.09%, P=0.04%, S=0.12%, CaO=2.13%, TiO2=2.4%, Al2O3=3.85%, and other trace elements 0.71%. Solid fuel includes sintered coal and coke powder with a mass ratio of 2:1. The requirements for various indicators of sintered coal and coke powder are: particle size less than 3mm volume percentage is 76%, low calorific value=28.32MJ / kg, moisture Mt=9.0%, fixed carbon FCad=81.43%, ash Ad=12.08%, volatile matter Vdaf=6.92%, sulfur S=0.32%; self-returned ore refers to sintered ore <5mm after crushing and screening, and the chemical composition and mass percentage are: TFe=59.4%, CaO=2.4%, V2O5=0.57%.

[0019] By controlling the sintering ignition temperature to 1050℃; The exhaust air and machine speed are adjusted according to the sintering end point temperature and position. The sintering machine end point temperature is controlled to be ≥460℃, and the sintering end point position is controlled at the second to last wind box. The exhaust is achieved by adjusting the air door opening and frequency conversion of the main exhaust fan to provide air volume for the sintering process; The machine speed is used to adjust the running speed of the main engine. The machine speed is adjusted twice per shift, each time by 0.05m / min.

[0020] The chemical composition and mass percentage of the vanadium-containing low-basicity sintered ore are: TFe=59.38%, V2O5=0.574%, CaO=2.38%, SiO2=5.62%, and binary basicity R=0.513.

[0021] The particle size of sintered ore is 5mm≤≤40mm, and the sintered ore is directly fed into the converter silo in the next step; The sintered ore with a particle size of less than 5mm is returned to the sintering machine for re-sintering. The sintered ore with a particle size of more than 40mm is crushed and screened, and the sintered ore with a particle size of ≤40mm and ≥5mm is put into the converter silo. The sintered ore with a particle size less than 5mm is returned to the sintering machine for re-sintering.

[0022] Example 1 Application The vanadium-containing low-basicity sintered ore with a particle size of 5mm≤≤40mm was transported to the converter silo by road. According to the CaO content of the sintered ore of 2.38%, 40kg / t of sintered ore for vanadium extraction and steelmaking was added into the converter as described in S10. No non-melting phenomenon occurred, the residual vanadium in the semi-steel and the temperature control met the process requirements, and 41.3kg of vanadium was added to one ton of steel. Example 2

[0023] A 360㎡ sintering machine in a certain factory produces vanadium-containing low-basicity sintered ore. Its sintering ore distribution structure is based on the ratio of vanadium-containing iron powder, solid fuel, and self-returned ore in 73.5:6.5:20, which is evenly distributed on the sintering machine trolley through belt transportation and sintering distribution. The moisture content of vanadium-containing iron powder is 9.5%. The chemical composition and mass percentage of vanadium-containing iron powder are: TFe=63.8% (converted to Fe2O3=91.14%), V2O5=0.771%, SiO2=2.02%, P=0.032%, S=0.11%, CaO=2.33%, TiO2=2.3%, Al2O3=0.50%, and other trace elements 0.8%. Solid fuel includes sintered coal and coke powder with a mass ratio of 2:1. The requirements for various indicators of sintered coal and coke powder are: particle size less than 3mm volume percentage is 72%, low calorific value=28.45MJ / kg, moisture Mt=9.1%, fixed carbon FCad=82.43%, ash Ad=12.13%, volatile matter Vdaf=6.77%, sulfur S=0.33%; self-returned ore refers to sintered ore <5mm after crushing and screening, and the chemical composition and mass percentage are: TFe=61.4%, CaO=2.66%, V2O5=0.55%.

[0024] By controlling the sintering ignition temperature to 1000℃; The exhaust air and machine speed are adjusted according to the sintering end point temperature and position. The sintering machine end point temperature is controlled at 450℃, and the sintering end point position is controlled at the second to last wind box. The exhaust is achieved by adjusting the air door opening and frequency conversion of the main exhaust fan to provide air volume for the sintering process; The machine speed is used to adjust the running speed of the main engine. The machine speed is adjusted once per shift, and each adjustment shall not exceed 0.01m / min.

[0025] The chemical composition and mass percentage of the vanadium-containing low-basicity sintered ore are: TFe=61.42%, V2O5=0.548%, CaO=2.66%, SiO2=5.49%, and binary basicity R=0.485.

[0026] The particle size of sintered ore is 5mm≤≤40mm, and the sintered ore is directly fed into the converter silo in the next step; The sintered ore with a particle size of less than 5mm is returned to the sintering machine for re-sintering. The sintered ore with a particle size of more than 40mm is crushed and screened, and the sintered ore with a particle size of ≤40mm and ≥5mm is put into the converter silo. The sintered ore with a particle size less than 5mm is returned to the sintering machine for re-sintering.

[0027] Example 2 Application The produced vanadium-containing low-basicity sintered ore was transported to the converter silo by road. According to the CaO content of the sintered ore of 2.66%, 36kg / t of sintered ore for vanadium extraction and steelmaking was added into the converter as described in S10. No non-melting phenomenon occurred, the residual vanadium in the semi-steel and the temperature control met the process requirements, and the vanadium was increased by 32.7kg per ton of steel. Example 3

[0028] A 360㎡ sintering machine in a certain factory produces vanadium-containing low-basicity sintered ore. Its sintering ore distribution structure is based on the ratio of vanadium-containing iron powder, solid fuel, and self-returned ore in 73.5:6.5:20, which is evenly distributed on the sintering machine trolley through belt transportation and sintering distribution. The moisture content of vanadium-containing iron powder is 9.3%. The chemical composition and mass percentage of vanadium-containing iron powder are: TFe=61.5% (converted to Fe2O3=87.86%), V2O5=0.82%, SiO2=2.04%, P=0.04%, S=0.16%, CaO=3.53%, TiO2=3.3%, Al2O3=1.45%, and other trace elements 0.8%. Solid fuel includes sintered coal and coke powder with a mass ratio of 2:1. The requirements for various indicators of sintered coal and coke powder are: particle size less than 3mm volume percentage is 72%, low calorific value=28.22MJ / kg, moisture Mt=8.9%, fixed carbon FCad=81.65%, ash Ad=12.32%, volatile matter Vdaf=6.52%, sulfur S=0.31%; self-returned ore refers to sintered ore <5mm after crushing and screening, and the chemical composition and mass percentage are: TFe=59.3%, CaO=3.43%, V2O5=0.57%.

[0029] By controlling the sintering ignition temperature to 1100°C; The exhaust air and machine speed are adjusted according to the sintering end point temperature and position. The sintering machine end point temperature is controlled at 440°C, and the sintering end point position is controlled at the second to last wind box. The exhaust is achieved by adjusting the air door opening and frequency conversion of the main exhaust fan to provide air volume for the sintering process; The machine speed is used to adjust the speed of the main engine. The machine speed is adjusted 3 times per shift, with each adjustment being 0.1m / min.

[0030] The chemical composition and mass percentage of the vanadium-containing low-basicity sintered ore are: TFe=59.3%, V2O5=0.57%, CaO=3.43%, SiO2=5.67%, and binary basicity R=0.604.

[0031] The particle size of sintered ore is 5mm≤≤40mm, and the sintered ore is directly fed into the converter silo in the next step; The sintered ore with a particle size of less than 5mm is returned to the sintering machine for re-sintering. The sintered ore with a particle size of more than 40mm is crushed and screened, and the sintered ore with a particle size of ≤40mm and ≥5mm is put into the converter silo. The sintered ore with a particle size less than 5mm is returned to the sintering machine for re-sintering.

[0032] Example 3 Application The produced vanadium-containing low-basicity sintered ore was transported to the converter silo by road. According to the CaO mass content of the sintered ore of 3.43%, 28kg / t of sintered ore for vanadium extraction and steelmaking was added into the converter as described in S10. No non-melting phenomenon occurred, the residual vanadium in the semi-steel and the temperature control met the process requirements, and the vanadium was increased by 30.2kg per ton of steel.

[0033] The above embodiments are only used to illustrate rather than limit the technical solutions of the present invention. Although the present invention is described in detail with reference to the above embodiments, those skilled in the art should understand that the present invention can still be modified or replaced by equivalents. Any modification or partial replacement that does not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A method for producing vanadium-containing low-basicity sintered ore, characterized in that: The following steps are involved: S10, various vanadium-containing iron powders, solid fuels, and self-returned ore are evenly distributed on the sintering machine trolley according to a certain ratio, and the vanadium-containing iron powder is sintered into ore to obtain sintered ore by adjusting sintering ignition, exhaust and machine speed.

2. The method for producing a vanadium-containing low-basicity sintered ore according to claim 1, characterized in that: In S1, the particle size of sintered ore is 5mm≤≤40mm, and the sintered ore is directly fed into the S2 converter silo; The particle size of the sintered ore is less than 5mm, and it is returned to the sintering machine for re-sintering; The sintered ore with particle size >40mm is crushed and screened to ≤40mm and ≥5mm and then put into S2 converter silo. The sintered ore with particle size less than 5mm is returned to the sintering machine for re-sintering.

3. The method for producing a vanadium-containing low-basicity sintered ore according to claim 1, characterized in that: The chemical composition and mass percentage of the sintered ore are: TFe≥58%, V2O5≥0.50%, CaO≤2.4%, SiO2≤3.5%; binary basicity R≤0.

69.

4. The method for producing a vanadium-containing low-basicity sintered ore according to claim 1, characterized in that: The mass ratio of vanadium-containing iron powder, solid fuel and self-return ore in S1 is 73.5:6.5:

20.

5. The method for producing a vanadium-containing low-basicity sintered ore according to claim 1, characterized in that: The sintering ignition temperature in S1 is 1050±50℃; The exhaust air and machine speed are adjusted according to the sintering end point temperature and position. The sintering machine end point temperature is controlled to be ≥400℃, and the sintering end point position is controlled at the second to last wind box. The exhaust is achieved by adjusting the air door opening and frequency conversion of the main exhaust fan to provide air volume for the sintering process; The machine speed is used to adjust the speed of the main engine. The machine speed should be adjusted no more than 3 times per shift, and each adjustment should not exceed 0.1m / min.

6. The method for producing a vanadium-containing low-basicity sintered ore according to claim 1, characterized in that: The moisture content of vanadium-containing ferro powder in S1 is controlled to be ≤10%. The chemical composition and mass percentage of vanadium-containing ferro powder are as follows: TFe≥63.5%, V2O5≥0.4%, SiO2≤5.0%, P≤0.075%, TiO2≤3.5%, Al2O3≤1.7%, S≤0.19%.

7. The method for producing a vanadium-containing low-basicity sintered ore according to claim 1, characterized in that: The solid fuel in S1 includes sintered coal and coke powder. The requirements for various indicators of sintered coal and coke powder are as follows: particle size less than 3mm, volume percentage> 75%, low calorific value ≥ 21MJ / kg, moisture Mt ≤ 9.5%, fixed carbon FCad ≥ 72%, ash Ad ≤ 20%, volatile matter Vdaf ≤ 10%, sulfur content S ≤ 1.0%; The mass ratio of sintered coal to coke powder is 2:

1.

8. The method for producing a vanadium-containing low-basicity sintered ore according to claim 1, characterized in that: The self-return ore in S1 refers to the sintered ore with a size of less than 5 mm after crushing and screening, and its chemical composition and mass percentage are: TFe≥58%, CaO≤2.4%, V2O5≥0.5%.

9. Application of the method for producing a vanadium-containing low-basicity sintered ore according to claim 1, characterized in that: For vanadium extraction and steelmaking, the sintered ore vanadium extraction and steelmaking production method comprises the following steps: S11, inspecting the CaO content in the sintered ore, and calculating the amount of sintered ore added in the vanadium extraction and steelmaking production according to the CaO content; S12. The amount of sintered ore added calculated according to S11 is transported by truck to the converter silo for vanadium extraction and steelmaking.

10. Application of the method for producing a vanadium-containing low-basicity sintered ore according to claim 9, characterized in that: The amount of sintered ore added in S11 is adjusted according to the CaO content in the sintered ore. When the CaO content in the sintered ore is greater than 6.4%, it will not meet the use requirements of the vanadium extraction converter. The specific addition amounts are as follows: (1) The mass percentage of CaO in the sintered ore is ≤2.4%, and the amount of sintered ore used for vanadium extraction and steelmaking is 40kg / t; (2) The mass percentage of CaO in the sintered ore is 2.4-2.8%, and the amount of sintered ore used for vanadium extraction and steelmaking is 30-40kg / t; (3) The mass percentage of CaO in the sintered ore is 2.8-3.7%, and the amount of sintered ore used for vanadium extraction and steelmaking is 20-30 kg / t; (4) The mass percentage of CaO in the sintered ore is 3.7-6.4%, and the amount of sintered ore used for vanadium extraction and steelmaking is 10-20kg / t.