Process for synergistically extracting vanadium from vanadium-titanium magnetite and stone coal vanadium ore

Abstract

This invention discloses a process for the co-extraction of vanadium from vanadium-titanium magnetite and vanadium shale coal. The process employs a side-blown furnace, with a clarification and vanadium blowing device connected to the end of the furnace via a chute. The side-blown furnace has a feed inlet at the top of its first end and a flue at the top of its last end. Multiple straight nozzles are installed on both sides of the furnace. The process includes the following steps: S1, uniformly mixing vanadium-titanium magnetite and vanadium shale coal in a specific ratio; S2, adding the mixed mineral material through the feed inlet of the side-blown furnace, and injecting pulverized coal and oxygen-enriched feed into the furnace through the straight nozzles. High-temperature smelting is carried out using air and natural gas; S3, after the smelting reaction is completed, the melt is discharged into the sluice box through the side-blown furnace outlet and then into the clarification and blowing vanadium device; the side-blown furnace of this application suppresses the generation of by-products such as TiC during the smelting process by injecting natural gas, so that the metal reduction reaction can be fully carried out, realizing the continuous melting and metal reduction process of mixed vanadium-titanium magnetite and shale coal vanadium ore, breaking the defects of traditional multi-process step-by-step processing, shortening the blast furnace and non-blast furnace smelting process, and reducing equipment investment, operating costs and environmental impact.

Description

Technical Field

[0001] This invention relates to the field of vanadium extraction technology from ores, and in particular to a process for the synergistic extraction of vanadium from vanadium-titanium magnetite and vanadium shale coal. Background Technology

[0002] Vanadium extraction from vanadium-titanium magnetite primarily employs pyrometallurgical techniques, with some hydrometallurgical methods also utilized. Early vanadium-titanium magnetite extraction used a blast furnace ironmaking-converter vanadium extraction process, achieving a vanadium recovery rate of only 40%-50%. This resulted in vanadium resource waste, large slag accumulation, high energy consumption, and significant CO2 emissions, causing severe environmental impact. Furthermore, during this blast furnace smelting process, titanium forms high-melting-point compounds (such as CaTiO3 and CaTiSiO5) with elements like calcium and silicon, leading to viscous slag that is difficult to remove. To address these problems with the blast furnace smelting process for vanadium-titanium magnetite, countries like South Africa and New Zealand have developed non-blast furnace smelting processes centered on direct reduction and smelting reduction. Examples include rotary kiln direct reduction-electric furnace smelting reduction-converter vanadium extraction. While current non-blast furnace smelting processes have improved vanadium recovery rates and titanium slag separation efficiency, they still suffer from high investment costs, long processes, and high energy consumption. In addition, vanadium-titanium magnetite can also be processed using a sodium roasting method. This involves mixing the vanadium with sodium salts in a rotary kiln for oxidative roasting, converting the vanadium oxides in the mineral into soluble vanadates. Vanadium is then leached out and separated by water leaching. The remaining titanium-iron pellets are then sent to a rotary kiln for reduction and an electric furnace for smelting to obtain molten iron and titanium slag, achieving slag-iron separation. While this method is technologically mature and requires relatively low investment, it generates harmful flue gas and high-salinity wastewater, leading to significant environmental problems.

[0003] Furthermore, while my country possesses abundant vanadium reserves in coal-fired power plants, the vanadium's occurrence is complex (primarily isomorphously embedded in silicate minerals such as mica). Traditional flat-kiln roasting and calcination roasting processes suffer from low vanadium recovery rates (only 30%-40%), high energy consumption, and severe pollution (excessive emissions of SO2 and Cl2). To optimize vanadium extraction from coal-fired power plants, non-roasting processes such as acid leaching (sulfuric acid / hydrochloric acid system), alkaline leaching (NaOH / Na2CO3 system), and microbial leaching have been developed domestically. By optimizing mineral liberation and enhancing mass transfer, these processes effectively improve vanadium recovery rates while avoiding roasting pollution. However, these leaching processes also present challenges such as the difficulty in resource-based disposal of leaching residue solid waste and high costs for some processes. Summary of the Invention

[0004] To reduce costs, decrease energy consumption, and improve efficiency, this application provides a process for the co-extraction of vanadium from vanadium-titanium magnetite and vanadium shale coal.

[0005] This application provides a process for the co-extraction of vanadium from vanadium-titanium magnetite and vanadium shale coal, employing the following technical solution:

[0006] A process for co-extracting vanadium from vanadium-titanium magnetite and vanadium shale coal ore, comprising a side-blown furnace, the end of which is connected to a clarification and vanadium blowing device via a chute; a feed inlet is located at the top of the beginning of the side-blown furnace, and a flue is located at the top of the end; multiple straight nozzles are provided on both sides of the side walls of the side-blown furnace, and the straight nozzles on both sides are aligned; the process includes the following steps:

[0007] S1. Mix vanadium-titanium magnetite and vanadium shale ore evenly in a certain proportion;

[0008] S2. Add the mixed mineral materials from the feed port of the side-blown furnace, and inject pulverized coal (oxygen-enriched air) and natural gas into the side-blown furnace through a straight nozzle for high-temperature smelting, so that the metal oxides such as iron and vanadium in the raw materials undergo a reduction reaction and form a melt, namely vanadium-containing molten iron and titanium slag.

[0009] S3. After the smelting reaction is completed, the melt is discharged into the chute through the side-blown furnace outlet and then into the clarification and vanadium blowing device.

[0010] Optionally, in step S2, the smelting temperature is 1450-1550℃, the pulverized coal dosage is 100-150 kg / ton of ore, the oxygen enrichment concentration is 70-80 vol%, and the bed capacity of the side-blown furnace is 40-50 t / m³. 2 •d, the residence time of the mineral material in the side-blown furnace is 2-3 hours, and the flue gas generated during the process is sent to the waste heat recovery system and purification device.

[0011] Optionally, all the straight nozzles are perpendicular to the side of the side-blown furnace, and 3 / 4 of the total number of straight nozzles are used to simultaneously spray pulverized coal and oxygen-enriched air, while the straight nozzles that spray natural gas account for 1 / 4 of the total number. The two types of straight nozzles are arranged alternately on the side of the side-blown furnace, driving the material to stir and tumble while injecting fuel and oxygen-enriched air.

[0012] Optionally, the side of the side-blown furnace near the tail end is also provided with an oblique nozzle. The width of the side-blown furnace is 2-2.4m, and the distance from the end of the side-blown furnace is L=400-500mm. The angle between the nozzle and the side of the side-blown furnace is α=30-40°. The nozzle sprays oxygen-enriched air to promote the fully reacted melt to be discharged to the outlet.

[0013] Optionally, in step S2, the straight nozzle is opened and the inclined nozzle is closed when the mineral material is smelted in the side-blown furnace, while the inclined nozzle is opened and the straight nozzle is closed when discharging; the side-blown furnace is continuously fed and intermittently discharged from the melt.

[0014] Optionally, the vanadium clarification and blowing device is a secondary side-blown furnace. The molten metal is discharged into the secondary side-blown furnace through the discharge port of the side-blown furnace into a chute. The secondary side-blown furnace is also equipped with a straight nozzle, and a slag discharge port and a molten iron discharge port at the tail end. The straight nozzle is opened to inject natural gas and oxygen-enriched air into the secondary side-blown furnace, raising the furnace temperature to 1500-1600℃. Then the straight nozzle is closed and the furnace is allowed to settle and clarify. When the temperature of the secondary side-blown furnace drops back to 1450-1550℃ and the clarification time reaches 30-40 minutes, the titanium slag is discharged from the slag discharge port of the side-blown furnace. After the titanium slag is separated, the straight nozzle is reopened to blow only oxygen-enriched air into the secondary side-blown furnace for oxygen-enriched blowing to extract vanadium. The blowing temperature is controlled at 1300-1350℃ and the blowing time is 4-7 minutes. After the blowing is completed, the vanadium slag is separated and recovered, and the molten iron after vanadium extraction is sent to the steelmaking system.

[0015] Optionally, the vanadium clarification and blowing device is an electric furnace. The molten metal is discharged into the electric furnace through the outlet of the side-blown furnace and fed into the chute. First, the titanium slag is removed by clarification and separation under heat preservation conditions. The heat preservation temperature is 1450-1550℃ and the clarification time is 30-40 minutes. After the titanium slag is separated, an oxygen-enriched blowing gun is inserted into the electric furnace for oxygen-enriched blowing to extract vanadium. The blowing temperature is controlled at 1300-1350℃ and the blowing time is 6-10 minutes. After the blowing is completed, the vanadium slag is separated and recovered, and the molten iron after vanadium extraction is sent to the steelmaking system.

[0016] In summary, this application includes the following beneficial technical effects:

[0017] (1) The side-blown furnace suppresses the generation of by-products such as TiC during the smelting process by injecting natural gas, so that the metal reduction reaction can be fully carried out. This realizes the continuous melting and metal reduction process of mixed mineral materials of vanadium-titanium magnetite and vanadium shale coal, breaks the defects of traditional multi-process step-by-step processing, shortens the smelting process of blast furnace and non-blast furnace, and reduces equipment investment, operating costs and environmental load.

[0018] (2) Side-blown furnace smelting effectively improves the gas-solid-liquid three-phase mixed system, enhances the mass and heat transfer of metal smelting, shortens the process time and reduces energy consumption; if the clarification of the smelted melt and vanadium blowing are completed in a secondary side-blown furnace, it is suitable for widespread use in areas with abundant natural gas; if it is completed in an electric furnace, it is suitable for widespread use in areas with abundant electricity.

[0019] (3) A combination of vanadium-titanium magnetite and vanadium shale ore was used as feedstock. Taking advantage of the dual characteristics of vanadium shale ore as both fuel and reducing medium, the reduction of iron and vanadium oxides was achieved while providing the heat required for smelting. By combining the side-blown furnace smelting-side-blown furnace / electric furnace clarification and vanadium blowing process, a complex and efficient multi-vanadium resource synergistic processing system was constructed, which improved the comprehensive recovery efficiency of vanadium resources. Attached Figure Description

[0020] Figure 1This is a front view of the overall structure of the device used in embodiments 1, 2, and 3 of this application;

[0021] Figure 2 This is a front view of the overall structure of the device used in embodiments 4, 5, and 6 of this application.

[0022] Explanation of reference numerals in the attached figures:

[0023] 1. Side-blown furnace; 2. Feed inlet; 3. Flue; 4. Straight nozzle; 5. Angled nozzle; 6. Chute; 7. Secondary side-blown furnace; 8. Slag discharge port; 9. Iron discharge port; 10. Electric furnace; 11. Electrode; 12. Blow gun. Detailed Implementation

[0024] The following is in conjunction with the appendix Figure 1-2 This application will be described in further detail.

[0025] This application discloses a process for co-extracting vanadium from vanadium-titanium magnetite and vanadium shale coal. The process uses a side-blown furnace 1, the end of which is connected to a clarification and vanadium blowing device via a chute 6. The top of the beginning end of the side-blown furnace 1 has a feed inlet, and the top of the end end has a flue 3. Multiple straight nozzles 4 are provided on both sides of the side walls of the side-blown furnace 1, and the straight nozzles 4 on both sides are aligned.

[0026] All straight nozzles 4 are perpendicular to the side of the side-blown furnace 1. The straight nozzles 4 used to spray pulverized coal and oxygen-enriched air account for 3 / 4 of the total, and the straight nozzles 4 used to spray natural gas account for 1 / 4 of the total. The two types of straight nozzles 4 are alternately aligned on the side of the side-blown furnace 1, and drive the material to stir and turn while injecting fuel and oxygen-enriched air.

[0027] The two sides near the end of the side-blown furnace 1 are also equipped with inclined nozzles 5. The overall width of the side-blown furnace 1 is 2-2.4m. The distance from the end of the side-blown furnace 1 to the inclined nozzles 5 is L=400-500mm. The angle between the direction of the nozzles and the horizontal direction of the side of the side-blown furnace 1 is α=30-40°. The nozzles spray oxygen-enriched air to promote the fully reacted melt to be discharged to the outlet.

[0028] The process includes the following steps:

[0029] S1. Mix vanadium-titanium magnetite and vanadium shale ore uniformly at a weight ratio of 1:(0.40-0.45), with the particle size of the mineral material being 200-300 mesh;

[0030] S2. The mixed ore material is added through the feed inlet 2 of the side-blown furnace 1. Pulverized coal (oxygen-enriched air) and natural gas are injected into the side-blown furnace 1 through the straight nozzle 4 for high-temperature smelting. This causes the iron, vanadium and other metal oxides in the raw material to undergo a reduction reaction and form a melt containing vanadium iron and titanium slag. The smelting temperature is 1450-1550℃, the pulverized coal dosage is 100-150 kg / ton of ore, the oxygen enrichment concentration is 70-80 vol%, and the bed capacity of the side-blown furnace 1 is 40-50 t / m³. 2 ·d, the residence time of the mineral material in the side-blown furnace 1 is 2-3 hours, and the flue gas generated during the process is sent to the waste heat recovery system and purification device; when the mineral material is smelted in the side-blown furnace 1, the straight nozzle 4 is opened and the inclined nozzle 5 is closed, while when discharging, the inclined nozzle 5 is opened and the straight nozzle 4 is closed; the side-blown furnace 1 is continuously fed and intermittently discharged melt.

[0031] S3. After the smelting reaction is completed, the melt is discharged into the chute 6 through the outlet of the side-blown furnace 1 and then into the clarification and vanadium blowing device; the clarification and vanadium blowing device is the electric furnace 10 or the secondary side-blown furnace 7.

[0032] When the vanadium clarification blowing device is a secondary side-blown furnace 7, the molten metal is discharged into the chute 6 through the outlet of the side-blown furnace 1 and enters the secondary side-blown furnace 7. The secondary side-blown furnace 7 is also equipped with a straight nozzle 4, and a slag discharge port 8 and a molten iron discharge port 9 at the tail end. The straight nozzle 4 is opened to inject natural gas and oxygen-enriched air into the secondary side-blown furnace 7, raising the furnace temperature to 1500-1600℃. Then the straight nozzle 4 is closed and the furnace is allowed to settle and clarify. When the temperature of the secondary side-blown furnace 7 drops back to 1450-1550℃ and the clarification time reaches 30-40 minutes, the titanium slag is discharged from the slag discharge port 8 of the side-blown furnace 1. After the titanium slag is separated, the straight nozzle 4 is reopened to blow only oxygen-enriched air into the secondary side-blown furnace 7 for oxygen-enriched blowing to extract vanadium. The blowing temperature is controlled at 1300-1350℃ and the blowing time is 4-7 minutes. After the blowing is completed, the vanadium slag is separated and recovered, and the molten iron after vanadium extraction is sent to the steelmaking system.

[0033] When the vanadium clarification blowing device is electric furnace 10, the molten metal is discharged into chute 6 through the outlet of side-blown furnace 1 and enters electric furnace 10. First, under the condition of heat preservation, titanium slag is removed by clarification and separation. The heat preservation temperature is 1450-1550℃ and the clarification time is 30-40min. After the titanium slag is separated, oxygen-enriched blowing guns are inserted into electric furnace 10 for oxygen-enriched blowing to extract vanadium. The blowing temperature is controlled at 1300-1350℃ and the blowing time is 6-10min. After the blowing is completed, the vanadium slag is separated and recovered, and the molten iron after vanadium extraction is sent to the steelmaking system.

[0034] The specific principle of the above process is as follows:

[0035] The principle of reduction smelting in a side-blown furnace 1 lies in the fact that iron oxides (such as Fe3O4) in the mixed mineral materials of vanadium-titanium magnetite and vanadium shale are reduced by C and CO at high temperatures to form molten iron, while high-valence vanadium oxides (V2O5) are reduced to V2O3 and enter the molten iron. During this high-temperature process, TiO2 is easily reduced to Ti in the strong reducing atmosphere of carbonaceous reducing agents, and then reacts with surrounding carbon and nitrogen to generate byproducts such as TiC and TiN, leading to increased slag viscosity and incomplete metal reduction reaction.

[0036] To reduce the generation of byproducts such as TiC and ensure the full reduction and smelting of iron and vanadium metals, while titanium remains stably in the smelting slag, this invention utilizes natural gas to partially replace pulverized coal, providing H2 through CH4 decomposition and reducing CO partial pressure. This enables one-step reduction smelting of vanadium-titanium magnetite and vanadium shale in a side-blown furnace 1 to form vanadium-containing molten iron and titanium slag. The principle of vanadium blowing in the electric furnace 10 / side-blown furnace 1 is that V2O3 in the vanadium-containing molten iron is oxidized to V2O5 by the blown-in O2 at high temperature, thereby precipitating from the molten iron to form a slag phase for vanadium recovery.

[0037] In the following embodiments, the hearth area of ​​the side-blown furnace for reduction smelting is 12m². 2 The hearth area of ​​the secondary side-blown furnace is 10m². 2 The furnace hearth area is 10m². 2 Vanadium-titanium magnetite contains 56.0% Fe, 0.7% V2O5, and 8.0% TiO2; vanadium shale contains 0.58% V2O5, 51% carbon, and 5% volatile matter.

[0038] Example 1

[0039] 17.3 t / h of vanadium-titanium magnetite and 7.7 t / h of coal shale were added to side-blown furnace 1. Then, 2.5 t / h of pulverized coal (80% oxygen-enriched air) and natural gas were injected through direct nozzle 4 for smelting, controlling the smelting temperature at 1450℃ for 2 hours. After smelting, the melt was discharged into secondary side-blown furnace 7. Natural gas and oxygen-enriched air were injected through direct nozzle 4 to raise the temperature of secondary side-blown furnace 7 to 1500℃. Then, direct nozzle 4 was closed, and the mixture was allowed to settle for 30 minutes to separate the titanium slag from the molten iron, discharging the titanium slag into a slag ladle. Vanadium extraction was then performed in secondary side-blown furnace 7 by blowing 80% oxygen-enriched air through direct nozzle 4 at a temperature of 1300℃ for 4 minutes. The vanadium-extracted molten iron was discharged from secondary side-blown furnace 7 into a ladle, and the vanadium slag was removed. The vanadium content of the vanadium-extracted molten iron was 0.09%, and the vanadium extraction rate reached 78%.

[0040] Example 2

[0041] 15.5 t / h of vanadium-titanium magnetite and 6.5 t / h of coal shale were added to side-blown furnace 1. Then, 3 t / h of pulverized coal (75% oxygen-enriched air) and natural gas were injected through direct nozzle 4 for smelting, controlling the smelting temperature at 1480℃ for 2.5 hours. The molten metal was then discharged into secondary side-blown furnace 7. Natural gas and oxygen-enriched air were injected through direct nozzle 4 to raise the temperature of secondary side-blown furnace 7 to 1530℃. Then, direct nozzle 4 was closed, and the mixture was allowed to settle for 35 minutes to separate the titanium slag from the molten iron, discharging the titanium slag into a slag ladle. Vanadium extraction was then performed in secondary side-blown furnace 7 by blowing 75% oxygen-enriched air through direct nozzle 4 at a temperature of 1320℃ for 6 minutes. The vanadium-extracted molten iron was discharged from electric furnace 10 into a ladle, and the vanadium slag was removed. The vanadium content of the extracted molten iron was 0.08%, and the vanadium extraction rate reached 80%.

[0042] Example 3

[0043] 14.2 t / h of vanadium-titanium magnetite and 5.8 t / h of coal shale were added to side-blown furnace 1. Then, 3 t / h of pulverized coal (70% oxygen-enriched air) and natural gas were injected through direct nozzle 4 for smelting, controlling the smelting temperature at 1500℃ for 3 hours. After smelting, the melt was discharged into secondary side-blown furnace 7. Natural gas and oxygen-enriched air were injected through direct nozzle 4 to raise the temperature of secondary side-blown furnace 7 to 1550℃. Then, direct nozzle 4 was closed, and the mixture was allowed to settle for 40 minutes to separate the titanium slag from the molten iron, discharging the titanium slag into a slag ladle. Vanadium extraction was then performed in secondary side-blown furnace 7 by blowing 70% oxygen-enriched air through direct nozzle 4 at a temperature of 1350℃ for 7 minutes. The vanadium-extracted molten iron was discharged from electric furnace 10 into a ladle, and the vanadium slag was removed. The vanadium content of the vanadium-extracted molten iron was 0.07%, and the vanadium extraction rate reached 83%.

[0044] The difference between Examples 4, 5, and 6 and Examples 1, 2, and 3 lies in the different vanadium-purifying devices. In the subsequent examples, the vanadium-purifying device is an electric furnace 10. There are no nozzles on the side wall of the electric furnace 10. The top of the electric furnace 10 is equipped with an electrode 11, which can keep the temperature inside the electric furnace 10 constant. It is also equipped with a flue 3 and a blowing gun. Similarly, the end of the electric furnace 10 is equipped with a slag discharge port 8 and a molten iron discharge port 9.

[0045] Example 4

[0046] 17.3 t / h of vanadium-titanium magnetite and 7.7 t / h of coal shale were added to side-blown furnace 1. Then, 2.5 t / h of pulverized coal (80% oxygen-enriched air) and natural gas were injected through direct nozzle 4 for smelting. The smelting temperature was controlled at 1450℃ for 2 hours. After smelting, the melt was discharged into electric furnace 10 and held at 1450℃ for 30 minutes to clarify and separate the titanium slag from the molten iron. The titanium slag was then discharged into a slag ladle. Subsequently, a blowtorch was inserted into the molten iron in electric furnace 10 to blow 80% oxygen-enriched air for vanadium extraction. The blowing temperature was 1300℃ for 9 minutes. The vanadium-extracted molten iron was discharged from electric furnace 10 into a ladle, and the vanadium slag was removed. The vanadium content of the vanadium-extracted molten iron was 0.1%, and the vanadium extraction rate reached 75%.

[0047] Example 5

[0048] 15.5 t / h of vanadium-titanium magnetite and 6.5 t / h of coal shale were added to the side-blown furnace 1. Then, 3 t / h of pulverized coal (75% oxygen-enriched air) and natural gas were injected through the straight nozzle 4 for smelting. The smelting temperature was controlled at 1480℃ for 2.5 hours. After smelting, the melt was discharged into the electric furnace 10 and held at 1480℃ for 35 minutes to separate the titanium slag from the molten iron. The titanium slag was then discharged into the slag ladle. Subsequently, a blowtorch was inserted into the molten iron in the electric furnace 10 to blow 75% oxygen-enriched air for vanadium extraction. The blowing temperature was 1320℃ for 8 minutes. The vanadium-extracted molten iron was discharged from the electric furnace 10 into the ladle, and the vanadium slag was removed. The vanadium content of the vanadium-extracted molten iron was 0.08%, and the vanadium extraction rate reached 80%.

[0049] Example 6

[0050] 14.2 t / h of vanadium-titanium magnetite and 5.8 t / h of coal shale were added to side-blown furnace 1. Then, 3 t / h of pulverized coal (70% oxygen-enriched air) and natural gas were injected through direct nozzle 4 for smelting. The smelting temperature was controlled at 1500℃ for 3 hours. After smelting, the melt was discharged into electric furnace 10 and held at 1500℃ for 40 minutes to separate the titanium slag from the molten iron. The titanium slag was then discharged into a slag ladle. Subsequently, a blowtorch was inserted into the molten iron in electric furnace 10 to blow 70% oxygen-enriched air for vanadium extraction. The blowing temperature was 1350℃ for 7 minutes. The vanadium-extracted molten iron was discharged from electric furnace 10 into a ladle, and the vanadium slag was removed. The vanadium content of the vanadium-extracted molten iron was 0.07%, and the vanadium extraction rate reached 83%.

[0051] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A process for synergistic vanadium extraction from vanadium-titanium magnetite and vanadium-bearing shale coal, characterized in that: This process employs a side-blown furnace, with its end connected to a vanadium clarification blowing device via a chute. A feed inlet is located at the top of the beginning of the side-blown furnace, and a flue is located at the top of the end. Multiple straight nozzles are installed on both sides of the furnace's side walls, with the nozzles aligned. The process includes the following steps: S1. Mix vanadium-titanium magnetite and vanadium shale coal ore evenly in a certain proportion; S2. Add the mixed mineral materials from the feed port of the side-blown furnace, and inject pulverized coal, natural gas and oxygen-enriched air into the side-blown furnace through a straight nozzle for high-temperature smelting, so that the iron and vanadium metal oxides in the raw materials undergo a reduction reaction and form a melt, namely vanadium-containing molten iron and titanium slag. S3. After the smelting reaction is completed, the melt is discharged into the chute through the side-blown furnace outlet and then into the clarification and vanadium blowing device. The vanadium clarification blowing unit is a secondary side-blown furnace. The molten metal is discharged into the secondary side-blown furnace through the discharge port of the side-blown furnace into a chute. The secondary side-blown furnace is also equipped with a straight nozzle, and a slag discharge port and a molten iron discharge port at the tail end. Natural gas and oxygen-enriched air are injected into the secondary side-blown furnace through the straight nozzle, raising the furnace temperature to 1500-1600°C. Then the straight nozzle is closed and the furnace is allowed to settle and clarify. When the temperature of the secondary side-blown furnace drops back to 1450-1550°C and the clarification time reaches 30-40 minutes, the titanium slag is discharged from the slag discharge port of the side-blown furnace. After the titanium slag is separated, the straight nozzle is reopened to blow only oxygen-enriched air into the secondary side-blown furnace for oxygen-enriched blowing to extract vanadium. The blowing temperature is controlled at 1300-1350°C and the blowing time is 4-7 minutes. After the blowing is completed, the vanadium slag is separated and recovered, and the molten iron after vanadium extraction is sent to the steelmaking system. Alternatively, the vanadium clarification and blowing device can be an electric furnace. The molten metal is discharged into the electric furnace through the outlet of the side-blown furnace and fed into the chute. First, the titanium slag is removed by clarification and separation under the condition of heat preservation. The heat preservation temperature is 1450-1550°C and the clarification time is 30-40 minutes. After the titanium slag is separated, an oxygen-enriched blowing gun is inserted into the electric furnace for oxygen-enriched blowing to extract vanadium. The blowing temperature is controlled at 1300-1350°C and the blowing time is 6-10 minutes. After the blowing is completed, the vanadium slag is separated and recovered, and the molten iron after vanadium extraction is sent to the steelmaking system.

2. The process for co-extracting vanadium from vanadium-titanium magnetite and vanadium-bearing shale coal according to claim 1, characterized in that: In step S2, the smelting temperature is 1450-1550°C, the pulverized coal consumption is 100-150 kg / ton of ore, the oxygen enrichment concentration is 70-80 vol%, and the bed capacity of the side-blown furnace is 40-50 t / m³. 2 •d, the residence time of the mineral material in the side-blown furnace is 2-3 hours, and the flue gas generated during the process is sent to the waste heat recovery system and purification device.

3. The process for synergistic vanadium extraction from vanadium-titanium magnetite and vanadium-bearing shale coal according to claim 2, characterized in that: All the straight nozzles are perpendicular to the side of the side-blown furnace, and 3 / 4 of the total number of straight nozzles are used to spray pulverized coal and oxygen-enriched air at the same time, while the straight nozzles that spray natural gas account for 1 / 4 of the total number; the two types of straight nozzles are arranged alternately on the side of the side-blown furnace, and while injecting fuel and oxygen-enriched air, they drive the material to stir and turn.

4. The process for co-extracting vanadium from vanadium-titanium magnetite and vanadium-bearing shale coal according to claim 3, characterized in that: The side of the side-blown furnace near the tail end is also equipped with an oblique nozzle. The width of the side-blown furnace is 2-2.4m. The oblique nozzle is 400-500mm away from the end of the side-blown furnace. The angle between its direction and the side of the side-blown furnace is α=30-40°. The nozzle sprays in oxygen-enriched air to promote the fully reacted melt to be discharged from the outlet.

5. The process for co-extracting vanadium from vanadium-titanium magnetite and vanadium-bearing shale coal according to claim 4, characterized in that: In step S2, the straight nozzle is opened and the inclined nozzle is closed when the mineral material is smelted in the side-blown furnace, while the inclined nozzle is opened and the straight nozzle is closed when the material is discharged; the side-blown furnace is continuously fed and intermittently discharged.

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