A system for carbon reduction of ferrovanadium and a method for preparing ferrovanadium

Abstract

A system for carbon reduction of ferrovanadium includes a material conveying device, a drying device, a tunnel kiln, and a carbon monoxide recycling device. The material conveying device is paved with a circular track that passes through the drying device and the tunnel kiln. The tunnel kiln includes a heating section, a reaction section, a sintering section, and a cooling section. The material conveying device passes through the heating section, the reaction section, the sintering section, and the cooling section in sequence. The reaction section is connected to the air outlet of the carbon monoxide recycling device to allow carbon monoxide to enter the reaction section, and the cooling section is connected to the air inlet of the carbon monoxide recycling device to recover carbon monoxide. In addition to participating in the reaction, carbon monoxide also serves as a protective gas, preventing outside air from entering the tunnel kiln. At the same time, the contact area between carbon monoxide and vanadium oxide is larger, the reaction rate is higher, the preparation time is shorter, and the resulting ferrovanadium is also higher in purity. The present invention also provides a method for preparing ferrovanadium.

Description

Technical Field

[0001] The present invention relates to the technical field of ferrovanadium production, and in particular to a system for carbon reduction of ferrovanadium and a method for preparing ferrovanadium. Background Art

[0002] Traditional ferrovanadium production involves uniformly mixing vanadium oxide, aluminum powder, and iron nails according to the required process ratio. The mixture is then loaded into a pre-prepared reactor and ignited using an ignition agent. The ignited material undergoes intense combustion, removing oxygen from the vanadium oxide. The mixture is then refined in a refining furnace. The refined discus is tipped out of the furnace using a tool, where it is cooled and crushed to produce the ferrovanadium product. Traditional ferrovanadium production is characterized by a lengthy process, discontinuous production, complex operations, intense reactions, and high production costs. Chinese invention patent application number 201911338495.8, entitled "A Method for Preparing 80 Ferrovanadium and 80 Ferrovanadium Produced Therewith," utilizes a pusher kiln, carbon as a reducing agent, and nitrogen or an inert gas as a shielding gas for continuous, large-scale ferrovanadium production. However, using nitrogen as a shielding gas can easily produce ferrovanadium nitride, and the carbon reduction of vanadium oxides takes a long time, resulting in low production efficiency and high production costs. Summary of the Invention

[0003] In view of this, it is necessary to provide a system for carbon reduction of ferrovanadium with high production efficiency and high purity of ferrovanadium.

[0004] There is also a need to provide a method for preparing ferrovanadium by using a carbon reduction system to prepare ferrovanadium.

[0005] A system for carbon reduction of vanadium iron includes a material conveying device, a drying device, a tunnel kiln, and a carbon monoxide recycling device. The material conveying device is paved with a circular track that passes through the drying device and the tunnel kiln. The tunnel kiln includes a heating section, a reaction section, a sintering section, and a cooling section. The material conveying device passes through the heating section, the reaction section, the sintering section, and the cooling section in sequence. The reaction section is connected to the air outlet of the carbon monoxide recycling device to introduce carbon monoxide into the reaction section. The cooling section is connected to the air inlet of the carbon monoxide recycling device to recover carbon monoxide.

[0006] In the above-mentioned system for carbon reduction of vanadium iron, preferably, the carbon monoxide recycling device includes a carbon monoxide filtering device, a carbon monoxide boosting device, and a carbon monoxide collecting device, the air inlet of the carbon monoxide filtering device is connected to the air outlet of the cooling section via a pipe, the air outlet of the carbon monoxide filtering device is connected to the air inlet of the carbon monoxide boosting device via a pipe, the air outlet of the carbon monoxide boosting device is connected to the air inlet of the carbon monoxide collecting device via a pipe, and the air outlet of the carbon monoxide collecting device is connected to the air inlet of the reaction section via a pipe.

[0007] In the above-mentioned system for carbon reduction of ferrovanadium, preferably, the carbon monoxide filtering device includes a sealed shell, a partition, and a dust bag. The air inlet of the sealed shell is connected to the carbon monoxide collection device through a pipeline, and the air outlet of the sealed shell is connected to the carbon monoxide boosting device through a pipeline. The partition divides the sealed shell into two independent chambers, and the air inlet and air outlet of the sealed shell are respectively located in the two independent chambers. A plurality of through holes are provided on the partition, and the bag opening of the dust bag is connected to the through holes of the partition to filter dust in the carbon monoxide.

[0008] In the above-mentioned system for carbon reduction of ferrovanadium, preferably, the carbon monoxide boosting device is a compressor.

[0009] In the above-mentioned system for carbon reduction of ferrovanadium, preferably, the carbon monoxide collection device is a pressure-resistant gas tank.

[0010] In the above-mentioned system for carbon reduction of ferrovanadium, preferably, the cross-sectional areas of the heating section, reaction section, sintering section, and cooling section decrease in sequence.

[0011] In the above-mentioned system for carbon reduction of ferrovanadium, preferably, the kiln body of the heating section includes a first insulation layer and multiple refractory layers, the first insulation layer is located outside the refractory layer, and the densities of the refractory layers from the outside to the inside are 0.8, 1.0, 1.2, 1.4, 1.7, and 2.3 g / cm 3 .

[0012] In the above-mentioned system for carbon reduction of ferrovanadium, preferably, the kiln body of the reaction section includes a second insulation layer and multiple refractory layers, the second insulation layer is located outside the refractory layer, and the density of the refractory layer from the outside to the inside is 0.8, 1.0, 1.2, 1.4, 1.7, 3.0 g / cm 3 .

[0013] In the above-mentioned system for carbon reduction of ferrovanadium, preferably, the kiln body of the sintering section includes a third insulation layer, multiple refractory layers, and a composite material lining layer, wherein the third insulation layer is located on the outside of the refractory layer, and the composite material lining layer is located on the inside of the refractory layer, and the density of the refractory layer from the outside to the inside is 0.8, 1.0, 1.2, 1.4, and 1.7 g / cm 3 .

[0014] In the above-mentioned system for carbon reduction of ferrovanadium, preferably, a cooling water jacket is provided on the side wall of the cooling section to cool the material.

[0015] A method for preparing ferrovanadium comprises the following steps:

[0016] Step S1: uniformly mixing vanadium oxide, carbon source, and iron in a predetermined mass ratio, pressing the mixture into a pelletizer, and pouring the mixture into a material conveying device;

[0017] Step S2: transporting the pressed material to a drying device through a material conveying device to reduce the moisture content in the mixed material;

[0018] Step S3: conveying the pressed material to the heating section of the tunnel kiln through a material conveying device, and continuously heating the material for 1 to 3 hours, wherein the temperature in the kiln of the heating section is less than or equal to 750 degrees Celsius;

[0019] Step S4: The pressed material is conveyed to the reaction section of the tunnel kiln via a material conveying device. Carbon monoxide is introduced into the reaction section. The material is retained in the reaction section for 2 to 8 hours to reduce the vanadium oxide to elemental vanadium. The temperature in the reaction section is 750 to 1250 degrees Celsius.

[0020] Step S5: The material is further transported to the sintering section of the tunnel kiln. The material is retained in the sintering section for 1 to 2 hours to fuse the vanadium and iron into a ferrovanadium alloy. The temperature in the kiln of the sintering section is 1250 to 1500 degrees Celsius.

[0021] Step S6: transporting the vanadium-ferroalloy to the cooling section of the tunnel kiln to cool it to a predetermined temperature before transporting it out.

[0022] Preferably, in step S1, the mass ratio of vanadium oxide: carbon: iron is (1.5-2.5): (0.5-2.0): (0.3-0.5).

[0023] Beneficial effects: When the system for carbon reduction of ferrovanadium of the present invention is in operation, the reaction raw materials are first mixed evenly according to a certain ratio, pressed into shape by a ball press and loaded into a material conveying device. The material conveying devices are neatly arranged on a circular track. As the material conveying device moves, the material first enters a drying device to dry the material, and then enters a tunnel kiln. It passes through a heating section, a reaction section, and a sintering section in succession. The ferrovanadium product is generated using carbon monoxide and a carbon source, and then cooled in a cooling section. After leaving the kiln, it is directly packaged as a sales product without the need for crushing. The entire production process can be carried out continuously. In addition to participating in the reaction, carbon monoxide is also a protective gas to prevent outside air from entering the tunnel kiln. At the same time, the contact area between carbon monoxide and vanadium oxide is larger, the reaction rate is higher, the preparation time is shorter, the purity of the generated ferrovanadium is also higher, and no external nitrogen element is introduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic structural diagram of the system for carbon reduction of ferrovanadium according to the present invention.

[0025] Figure 2 It is a structural schematic diagram of the temperature rising section of the system for carbon reduction of ferrovanadium according to the present invention.

[0026] Figure 3 It is a schematic structural diagram of the reaction section of the system for carbon reduction of ferrovanadium according to the present invention.

[0027] Figure 4 It is a schematic structural diagram of the sintering section of the system for carbon reduction of ferrovanadium according to the present invention.

[0028] In the figure: a system 10 for carbon reduction of ferrovanadium, a material conveying device 20, a circular track 201, a drying device 30, a tunnel kiln 40, a heating section 401, a first insulation layer 4011, a refractory layer 4012, a reaction section 402, a second insulation layer 4021, a refractory layer 4022, a sintering section 403, a third insulation layer 4031, a refractory layer 4032, a composite material lining 4033, a cooling section 404, a carbon monoxide recycling device 50, a carbon monoxide filtering device 501, a carbon monoxide boosting device 502, and a carbon monoxide collecting device 503. DETAILED DESCRIPTION

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Please see Figure 1 A system 10 for carbon reduction of vanadium iron includes a material conveying device 20, a drying device 30, a tunnel kiln 40, and a carbon monoxide recycling device 50. The material conveying device 20 is paved with a circular track 201, which passes through the drying device 30 and the tunnel kiln 40. The tunnel kiln 40 includes a heating section 401, a reaction section 402, a sintering section 403, and a cooling section 404. The material conveying device 20 passes through the heating section 401, the reaction section 402, the sintering section 403, and the cooling section 404 in sequence. The reaction section 402 is connected to the air outlet of the carbon monoxide recycling device 50 to introduce carbon monoxide into the reaction section 402. The cooling section 404 is connected to the air inlet of the carbon monoxide recycling device 50 to recover carbon monoxide.

[0031] The system 10 for carbon reduction of ferrovanadium according to the present invention uses carbon monoxide as both a protective gas and a reactive gas. This prevents outside air from entering the tunnel kiln 40 and participating in the vanadium reaction, while also allowing sufficient contact with the vanadium oxide to reduce the vanadium oxide to elemental vanadium. As a gas, its contact level is higher than that of carbon with vanadium oxide, and the reaction process with vanadium oxide is also faster. Simultaneously, carbon and vanadium oxide also react to form elemental vanadium, thereby accelerating the reaction process. The vanadium oxide described in the present invention refers to vanadium trioxide or vanadium pentoxide. Vanadium trioxide or vanadium pentoxide reacts with carbon monoxide or carbon to form elemental vanadium, carbon dioxide, or carbon monoxide. The generated carbon dioxide can also react with carbon at high temperatures to form carbon monoxide, thereby maintaining a carbon monoxide environment within the tunnel kiln 40 and allowing the carbon monoxide to be recycled. As the number of cycles increases, the concentration of carbon monoxide gradually increases, and excess carbon monoxide can be stored as fuel or raw material.

[0032] Driven by the carbon monoxide flow, dust in the material will also enter the airflow. Therefore, further, the carbon monoxide recycling device 50 includes a carbon monoxide filter device 501, a carbon monoxide booster device 502, and a carbon monoxide collection device 503. The air inlet of the carbon monoxide filter device 501 is connected to the air outlet of the cooling section 404 via a pipeline, the air outlet of the carbon monoxide filter device 501 is connected to the air inlet of the carbon monoxide booster device 502 via a pipeline, the air outlet of the carbon monoxide booster device 502 is connected to the air inlet of the carbon monoxide collection device 503 via a pipeline, and the air outlet of the carbon monoxide collection device 503 is connected to the air inlet of the reaction section 402 via a pipeline.

[0033] The dust in the airflow is filtered out by the carbon monoxide filter 501. At the same time, the carbon monoxide booster 502 is set to increase the pressure of the airflow to maintain the positive pressure in the tunnel kiln 40, and the carbon monoxide collection device 503 buffers the airflow to maintain a stable pressure in the tunnel kiln 40.

[0034] In a preferred embodiment, a section of the annular track 201 in the tunnel kiln 40 is made of a high-temperature resistant material.

[0035] The material conveying device 20 of the present invention comprises a load-bearing carriage capable of moving along a circular track 201. The carriage is driven by a high-temperature-resistant chain or telescopic rod. Because the tunnel kiln is relatively long, several carriages are positioned end-to-end for efficient operation. This allows each carriage to move forward a certain distance by simply pushing the carriage preceding the heating section.

[0036] In a preferred embodiment, the carbon monoxide filtering device includes a sealed shell, a partition, and a dust bag. The air inlet of the sealed shell is connected to the carbon monoxide collection device 503 through a pipe, and the air outlet of the sealed shell is connected to the carbon monoxide boosting device 502 through a pipe. The partition divides the sealed shell into two independent chambers. The air inlet and the air outlet of the sealed shell are respectively located in the two independent chambers. A number of through holes are provided on the partition, and the bag opening of the dust bag is connected to the through holes of the partition to filter dust in the carbon monoxide.

[0037] In a preferred embodiment, the carbon monoxide boosting device 502 is a compressor.

[0038] In a preferred embodiment, the carbon monoxide collection device 503 is a pressure-resistant gas cylinder.

[0039] In a preferred embodiment, the cross-sectional areas of the heating section 401, reaction section 402, sintering section 403, and cooling section 404 decrease in sequence. The kiln temperature in the heating section 401 is 0-750°C, the kiln temperature in the reaction section 402 is 750-1250°C, and the kiln temperature in the vanadium oxide sintering section 403 is 1250-1500°C. As the cross-sectional areas decrease in sequence, the corresponding pressure also gradually increases, forming an airflow channel from the cooling section 404, sintering section 403, and reaction section 402.

[0040] In a preferred embodiment, see Figure 2 The kiln body of the heating section 401 includes a first insulation layer 4011 and multiple refractory layers 4012. The first insulation layer 4011 is located outside the refractory layer 4012. The densities of the refractory layers 4012 are 0.8, 1.0, 1.2, 1.4, 1.7, and 2.3 g / cm3 from outside to inside. 3 .

[0041] In a preferred embodiment, see Figure 3 The kiln body of the reaction section 402 includes a second insulation layer 4021 and multiple refractory layers 4022. The second insulation layer 4021 is located outside the refractory layer 4022. The densities of the refractory layers 4022 are 0.8, 1.0, 1.2, 1.4, 1.7, and 3.0 g / cm3 from outside to inside. 3 .

[0042] In a preferred embodiment, see Figure 4The kiln body of the sintering section 403 includes a third insulation layer 4031, multiple refractory layers 4032, and a composite material lining layer 4033. The third insulation layer 4031 is located on the outside of the refractory layer 4032, and the composite material lining layer 4033 is located on the inside of the refractory layer 4032. The density of the refractory layer 4032 is 0.8, 1.0, 1.2, 1.4, and 1.7 g / cm3 from the outside to the inside, respectively. 3 .

[0043] The refractory layer is constructed of alumina refractory bricks. The thickness of the alumina refractory bricks is 65 mm. The lower the density of the refractory bricks, the better the thermal insulation performance, but the lower the high-temperature resistance. The density of the refractory layer 4012 of the kiln gradually increases inward, providing excellent thermal insulation performance while also being able to withstand high temperatures.

[0044] In a preferred embodiment, a cooling water jacket is provided on the side wall of the cooling section 404 to cool the material.

[0045] A method for preparing ferrovanadium comprises the following steps:

[0046] Step S1: uniformly mixing vanadium oxide, carbon source, and iron in a predetermined mass ratio, pressing the mixture into a pelletizer, and pouring the mixture into a material conveying device;

[0047] Step S2: transporting the pressed material to a drying device through a material conveying device to reduce the moisture content in the mixed material;

[0048] Step S3: conveying the pressed material to the heating section of the tunnel kiln through a material conveying device, and continuously heating the material for 1 to 3 hours, wherein the temperature in the kiln of the heating section is less than or equal to 750 degrees Celsius;

[0049] Step S4: The pressed material is conveyed to the reaction section of the tunnel kiln via a material conveying device. Carbon monoxide is introduced into the reaction section. The material is retained in the reaction section for 2 to 8 hours to reduce the vanadium oxide to elemental vanadium. The temperature in the reaction section is 750 to 1250 degrees Celsius.

[0050] Step S5: The material is further transported to the sintering section of the tunnel kiln. The material is retained in the sintering section for 1 to 2 hours to fuse the vanadium and iron into a ferrovanadium alloy. The temperature in the kiln of the sintering section is 1250 to 1500 degrees Celsius.

[0051] Step S6: transporting the vanadium-ferroalloy to the cooling section of the tunnel kiln to cool it to a predetermined temperature before transporting it out.

[0052] Furthermore, in step S1, the mass ratio of vanadium oxide: carbon: iron is (1.5-2.5): (0.5-2.0): (0.3-0.5).

[0053] Taking 80 ferrovanadium as an example, the preparation method of the ferrovanadium of the present invention will be described below through specific examples.

[0054] Example 1:

[0055] Vanadium pentoxide, clean coal and iron filings in a mass ratio of 1.5:0.5:0.3 are mixed evenly and pressed into shape using a briquette machine, and then poured into the compartment of the material conveying device; the compartment is pushed to convey the pressed material to the drying device through the material conveying device to reduce the moisture content in the mixed material; the compartment is continued to be pushed to convey the pressed material to the heating section of the tunnel kiln through the material conveying device, and the material is continuously heated for 2 hours. The temperature in the kiln of the heating section is controlled at 750 degrees Celsius; then the compartment is continued to be pushed The pressed material is conveyed to the reaction section of the tunnel kiln through a material conveying device. Carbon monoxide is introduced into the reaction section. The material is retained in the reaction section for 5 hours to reduce the vanadium oxide to simple vanadium. The temperature in the reaction section is 1250 degrees Celsius. The material is further conveyed to the sintering section of the tunnel kiln. The material is retained in the sintering section for 1.5 hours to fuse the simple vanadium and iron into vanadium-iron alloy. The temperature in the sintering section is 1500 degrees Celsius. The vanadium-iron alloy is conveyed to the cooling section of the tunnel kiln to be cooled to a predetermined temperature before being transported out.

[0056] Example 2:

[0057] Vanadium pentoxide, clean coal and iron filings in a mass ratio of 1.5:0.5:0.3 are mixed evenly, pressed into shape using a briquette machine, and poured into the compartment of a material conveying device; the compartment is pushed to convey the pressed material to a drying device through the material conveying device to reduce the moisture content of the mixed material; the compartment is continued to be pushed to convey the pressed material to the heating section of the tunnel kiln through the material conveying device, and the material is continuously heated for 2 hours, and the temperature in the kiln of the heating section is controlled at 750 degrees Celsius; thereafter, the compartment is continued to be pushed to convey the pressed material to the reaction section of the tunnel kiln through the material conveying device, and carbon monoxide is introduced into the reaction section. The material is retained in the reaction section for 1 hour, and the temperature in the kiln of the reaction section is 1250 degrees Celsius; the material is further conveyed to the sintering section of the tunnel kiln, and the material is retained in the sintering section for 1.5 hours to fuse the vanadium element and iron into a vanadium-iron alloy, and the temperature in the kiln of the sintering section is 1500 degrees Celsius; the vanadium-iron alloy is conveyed to the cooling section of the tunnel kiln, cooled to a predetermined temperature, and then transported out.

[0058] Example 3:

[0059] Vanadium pentoxide, clean coal and iron filings in a mass ratio of 1.5:0.5:0.3 are mixed evenly, pressed into shape using a briquette machine, and poured into the compartment of a material conveying device; the compartment is pushed to convey the pressed material to a drying device through the material conveying device to reduce the moisture content of the mixed material; the compartment is continued to be pushed to convey the pressed material to the heating section of the tunnel kiln through the material conveying device, and the material is continuously heated for 2 hours, and the temperature in the kiln of the heating section is controlled at 750 degrees Celsius; thereafter, the compartment is continued to be pushed to convey the pressed material to the reaction section of the tunnel kiln through the material conveying device, and nitrogen is introduced into the reaction section. The material is retained in the reaction section for 1 hour, and the temperature in the kiln of the reaction section is 1250 degrees Celsius; the material is further conveyed to the sintering section of the tunnel kiln, and the material is retained in the sintering section for 1.5 hours to fuse the vanadium element and iron into vanadium-iron alloy, and the temperature in the kiln of the sintering section is 1500 degrees Celsius; the vanadium-iron alloy is conveyed to the cooling section of the tunnel kiln, cooled to a predetermined temperature, and then transported out.

[0060] The composition of the vanadium-iron alloy prepared in each embodiment was tested, and the mass percentage of each element is shown in Table 1:

[0061] Table 1: Mass percentage of each component of vanadium-ferroalloy

[0062]

[0063]

[0064] In the table, the vanadium oxide in Example 1 has been completely reacted. After the material has reacted for a period of time, the oxygen content of the vanadium iron in Example 2 is significantly lower than the oxygen content of the vanadium iron in Example 3. This shows that after a period of reaction, the content of vanadium oxide in Example 2 is lower than the content of vanadium oxide in Example 3, indicating that more vanadium in the vanadium oxide is reduced. Using carbon monoxide as a protective gas, when the time of the reaction section is controlled to 1h, the rate at which vanadium pentoxide in Example 2 is reduced is greater than the rate at which nitrogen is used as a protective gas, and the various indicators after the reaction are far superior to those in Example 3. And using carbon monoxide as a protective gas, no new impurities, such as vanadium nitride, will be generated. Through instrumental detection, the nitrogen content of the product in Example 2 is extremely low and can be ignored, recorded as 0. This shows that when carbon monoxide is used as a protective gas in a tunnel kiln to prepare vanadium iron alloy, no external nitrogen element is introduced, and the purity of the generated vanadium iron is also higher. At the same time, compared to the case where a solid carbon source is used as a reducing agent, the residual carbon content in the ferrovanadium product is 6.3%, which is lower than the 9.1% in Example 3, a decrease of 30.1%. The residual oxygen content in the ferrovanadium product in Example 2 is 7.2%, significantly lower than the 14.9% in Example 3, a decrease of 51.7%. Carbon monoxide can participate in the reduction reaction of vanadium oxide, thereby accelerating the reduction process of vanadium. The carbon dioxide generated after the carbon monoxide reaction undergoes a reduction reaction with carbon in a high-temperature environment to regenerate carbon monoxide. Compared with nitrogen as a shielding gas, this does not introduce new impurities into the shielding gas.

[0065] The above disclosure is only a preferred embodiment of the present invention, and it is certainly not intended to limit the scope of the present invention. A person skilled in the art can understand that all or part of the processes of the above embodiment and equivalent changes made in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A system for carbon reduction of ferrovanadium, characterized by: The invention comprises a material conveying device, a drying device, a tunnel kiln and a carbon monoxide recycling device. The material conveying device is paved with a circular track, which passes through the drying device and the tunnel kiln. The tunnel kiln comprises a heating section, a reaction section, a sintering section and a cooling section. The material conveying device passes through the heating section, the reaction section, the sintering section and the cooling section in sequence. The reaction section is connected to the air outlet of the carbon monoxide recycling device to introduce carbon monoxide into the reaction section. The cooling section is connected to the air inlet of the carbon monoxide recycling device to recover carbon monoxide.

2. The system for carbon reduction of ferrovanadium according to claim 1, characterized in that: The carbon monoxide recycling device includes a carbon monoxide filtering device, a carbon monoxide boosting device, and a carbon monoxide collecting device. The air inlet of the carbon monoxide filtering device is connected to the air outlet of the cooling section via a pipeline, the air outlet of the carbon monoxide filtering device is connected to the air inlet of the carbon monoxide boosting device via a pipeline, the air outlet of the carbon monoxide boosting device is connected to the air inlet of the carbon monoxide collecting device via a pipeline, and the air outlet of the carbon monoxide collecting device is connected to the air inlet of the reaction section via a pipeline.

3. The system for carbon reduction of ferrovanadium according to claim 2, characterized in that: The carbon monoxide filtering device includes a sealed shell, a partition, and a dust bag. The air inlet of the sealed shell is connected to the carbon monoxide collection device through a pipeline, and the air outlet of the sealed shell is connected to the carbon monoxide boosting device through a pipeline. The partition divides the sealed shell into two independent chambers. The air inlet and the air outlet of the sealed shell are respectively located in the two independent chambers. The partition is provided with a plurality of through holes. The bag opening of the dust bag is connected to the through holes of the partition to filter dust in the carbon monoxide.

4. The system for carbon reduction of ferrovanadium according to claim 1, characterized in that: The cross-sectional areas of the heating section, reaction section, sintering section and cooling section decrease in sequence.

5. The system for carbon reduction of ferrovanadium according to claim 1, characterized in that: The kiln body of the heating section includes a first insulation layer and multiple refractory layers. The first insulation layer is located outside the refractory layer. The densities of the refractory layers from outside to inside are 0.8, 1.0, 1.2, 1.4, 1.7, and 2.3 g / cm 3 .

6. The system for carbon reduction of ferrovanadium according to claim 1, characterized in that: The kiln body of the reaction section includes a second insulation layer and multiple refractory layers. The second insulation layer is located outside the refractory layer. The densities of the refractory layers from outside to inside are 0.8, 1.0, 1.2, 1.4, 1.7, and 3.0 g / cm 3 .

7. The system for carbon reduction of ferrovanadium according to claim 1, characterized in that: The kiln body of the sintering section includes a third insulation layer, multiple refractory layers, and a composite material lining layer. The third insulation layer is located on the outside of the refractory layer, and the composite material lining layer is located on the inside of the refractory layer. The densities of the refractory layers from the outside to the inside are 0.8, 1.0, 1.2, 1.4, and 1.7 g / cm 3 .

8. The system for carbon reduction of ferrovanadium according to claim 1, characterized in that: The side wall of the cooling section is provided with a cooling water jacket to cool the material.

9. A method for preparing ferrovanadium, characterized in that: The following steps are involved: Step S1: uniformly mixing vanadium oxide, carbon source, and iron in a predetermined mass ratio, pressing the mixture into a pelletizer, and pouring the mixture into a material conveying device; Step S2: transporting the pressed material to a drying device through a material conveying device to reduce the moisture content in the mixed material; Step S3: conveying the pressed material to the heating section of the tunnel kiln through a material conveying device, and continuously heating the material for 1 to 3 hours, wherein the temperature in the kiln of the heating section is less than or equal to 750 degrees Celsius; Step S4: The pressed material is conveyed to the reaction section of the tunnel kiln via a material conveying device. Carbon monoxide is introduced into the reaction section. The material is retained in the reaction section for 2 to 8 hours to reduce the vanadium oxide to elemental vanadium. The temperature in the reaction section is 750 to 1250 degrees Celsius. Step S5: The material is further transported to the sintering section of the tunnel kiln. The material is retained in the sintering section for 1 to 2 hours to fuse the vanadium and iron into a ferrovanadium alloy. The temperature in the kiln of the sintering section is 1250 to 1500 degrees Celsius. Step S6: transporting the vanadium-ferroalloy to the cooling section of the tunnel kiln to cool it to a predetermined temperature before transporting it out.

10. The method for preparing ferrovanadium according to claim 9, wherein: In step S1 , the mass ratio of vanadium oxide: carbon: iron is (1.5-2.5): (0.5-2.0): (0.3-0.5).

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