An ultra-high purity vanadium pentoxide tablet production device

Abstract

The present invention discloses a production device for ultra-high purity tablet vanadium pentoxide, which includes a melting furnace body. A preheating zone and a high-temperature zone are provided in the furnace chamber of the melting furnace body. Both the preheating zone and the high-temperature zone include multiple temperature zones, and adjacent temperature zones are separated by heat insulation components. In the production device for ultra-high purity tablet vanadium pentoxide disclosed by the present invention, the furnace chamber is divided into a preheating zone and a high-temperature zone, and multiple heat insulation components are provided in both the preheating zone and the high-temperature zone. Stepwise temperature control is adopted, and the melting speed of vanadium pentoxide is controlled by using the temperature difference to ensure that the powdered vanadium pentoxide is fully melted and prevent the powdered vanadium pentoxide from being mixed into the finished product.

Description

Technical Field

[0001] The present invention relates to the field of vanadium-aluminum alloy melting equipment, and particularly to a production equipment for ultra-high purity tablet vanadium pentoxide. Background Art

[0002] Titanium alloys represented by Ti-6Al-4V (grade TC4) have excellent properties and are of great strategic significance in fields such as aerospace. Vanadium-aluminum alloy, as an essential raw material for producing titanium alloys, its quality is the key factor determining the quality of TC4 titanium alloy. Currently, only a few countries in the world master the melting technology of aerospace-grade vanadium-aluminum alloy. The raw material vanadium pentoxide for producing vanadium-aluminum alloy in China is used after being converted into tablets from ultra-high purity vanadium pentoxide powder. Since the vanadium pentoxide powder is purified by chemical methods, the impurity content in the process is relatively easy to control. However, in the subsequent process of converting ultra-high purity vanadium pentoxide powder into tablets, it is achieved by pyrometallurgy, and its impurity content is difficult to control. There is a problem of relatively high impurity content in ultra-high purity tablet vanadium pentoxide in China, especially the contents of silicon, iron, and carbon are extremely easy to exceed the standard, and it cannot meet the requirements for preparing high-quality vanadium-aluminum alloy (V2O5≥99.5%, other single impurity elements≤0.05%). Therefore, it is particularly urgent to develop a device for preparing ultra-high purity tablet vanadium pentoxide.

[0003] The Chinese patent document with the application number 201711348672.1 discloses a preparation method for aerospace-grade tablet vanadium pentoxide, introducing that the rapid melting furnace adopts multi-point short-distance flat flame heating, water-cooled furnace bottom, and arched furnace top; the Chinese patent document with the application number 201110082422.4 discloses a melting furnace, which is heated by setting burners for injecting kerosene and oxygen to prepare tablet vanadium pentoxide. In both schemes, the melting furnace equipment adopts fuel or gas heating methods. This type of traditional melting furnace equipment has the following problems during the phase change process of vanadium pentoxide:

[0004] (1) During the fuel combustion process, the carbon content of the product is relatively high;

[0005] (2) Dust is generated during the fuel entering the furnace chamber, resulting in a decrease in vanadium recovery rate;

[0006] (3) During the combustion process, the temperature around the burner is high and the temperature in the distance is low, the temperature in the furnace chamber is uneven, the molten vanadium pentoxide is prone to caking, the melting is insufficient, and the finished product is easy to mix with powdered vanadium pentoxide;

[0007] (4) The furnace chamber is lined with refractory bricks, which are extremely easy to introduce impurities (such as silicon, iron, etc.);

[0008] (5) Incomplete combustion of the fuel will produce carbon monoxide, which is a reducing agent and will reduce part of vanadium pentoxide to vanadium tetraoxide or vanadium trioxide, resulting in the mixing of low-valence vanadium in the product.

[0009] To sum up, the traditional melting furnace equipment has problems such as low vanadium recovery rate, easy caking of molten vanadium pentoxide, high carbon content, and extremely easy mixing of low-valence vanadium tetraoxide or vanadium trioxide, which seriously restricts the production of ultra-high-purity tablet vanadium pentoxide in China and cannot meet the production requirements of aviation-grade high-quality vanadium-aluminum alloy. Summary of the Invention

[0010] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a production equipment for ultra-high-purity tablet vanadium pentoxide that is conducive to controlling the melting speed, ensuring the full melting of powdered vanadium pentoxide, and avoiding the mixing of powdered vanadium pentoxide in the finished product.

[0011] To solve the above technical problem, the present invention adopts the following technical solutions:

[0012] A production equipment for ultra-high-purity tablet vanadium pentoxide includes a melting furnace body. Inside the furnace chamber of the melting furnace body, there are a preheating zone and a high-temperature zone. Both the preheating zone and the high-temperature zone include multiple temperature zones, and adjacent temperature zones are separated by heat-insulating components.

[0013] As a further improvement of the above technical solution: the temperature of the preheating zone is 500 - 700 °C, and the slope of the bottom of the furnace chamber corresponding to the preheating zone is 10 - 15 °.

[0014] As a further improvement of the above technical solution: the temperature of the high-temperature zone is 700 - 1000 °C, and the slope of the bottom of the furnace chamber corresponding to the high-temperature zone is 5 - 10 °.

[0015] As a further improvement of the above technical solution: the melting furnace body is provided with a plurality of air inlets, and each air inlet is arranged in one-to-one correspondence with each temperature zone.

[0016] As a further improvement of the above technical solution: the bottom of the furnace chamber is provided with a ceramic inner liner.

[0017] As a further improvement of the above technical solution: a resistance heating device is provided inside the furnace chamber.

[0018] As a further improvement of the above technical solution: a feeding device is provided on one side of the melting furnace body. The feeding device includes a rail trolley, a storage bin and a screw feeder arranged on the rail trolley. The screw feeder is docked with the storage bin. Tungsten carbide coatings are provided on the inner wall of the storage bin and the inner wall of the conveying pipe of the screw feeder. The discharge bin is also equipped with a vibrator.

[0019] As a further improvement of the above technical solution: a dust collector is also provided on the rail trolley.

[0020] As a further improvement of the above technical solution: the heat insulation component is a pressureless sintered silicon carbide square beam.

[0021] As a further improvement of the above technical solution: an outlet heating device and a discharging slide plate are provided on the other side of the melting furnace body. The discharging slide plate is connected to a discharging device. The heating temperature of the outlet heating device is 500-800°C, and the slope of the discharging slide plate is 5-10°.

[0022] As a further improvement of the above technical solution: the outlet heating device includes alloy resistance wires and a polycrystalline mullite fiber material heat insulation layer provided outside the alloy resistance wires. The inner wall of the discharging slide plate is provided with a tungsten carbide coating.

[0023] Compared with the prior art, the advantages of the present invention are as follows: the ultra-high purity tablet vanadium pentoxide production equipment disclosed by the present invention has a furnace chamber divided into a preheating zone and a high-temperature zone. A plurality of heat insulation components are provided in both the preheating zone and the high-temperature zone. Stepwise temperature control is adopted, and the melting speed of vanadium pentoxide is controlled by using the temperature difference to ensure that the powdered vanadium pentoxide is fully melted and to avoid the mixing of powdered vanadium pentoxide in the finished product. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic structural diagram of the ultra-high purity tablet vanadium pentoxide production equipment of the present invention.

[0025] Each label in the figure represents: 1. Melting furnace body; 10. Furnace chamber; 11. Preheating zone; 12. High-temperature zone; 13. Air inlet; 14. Exhaust port; 15. Heat insulation component; 2. Resistance heating device; 3. Feeding device; 30. Rail trolley; 31. Storage bin; 32. Screw feeder; 33. Dust collector; 4. Outlet heating device; 5. Discharging slide plate; 6. Discharging device. DETAILED DESCRIPTION OF THE INVENTION

[0026] As shown in this part and the claims, unless the context clearly indicates otherwise, words such as "a", "an", "one" and / or "the" are not specifically singular and may also include plural. The words "first", "second" and similar words used in this part do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "comprising" or "including" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. "Connection" or "coupling" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0027] The present invention will be further described in detail below in conjunction with the accompanying drawings of the specification and specific embodiments.

[0028] Figure 1 An embodiment of the production equipment for ultra-high purity tablet vanadium pentoxide of the present invention is shown. The process of preparing ultra-high purity tablet vanadium pentoxide using the production equipment for ultra-high purity tablet vanadium pentoxide of this embodiment is as follows:

[0029] Ultra-high purity powdered vanadium pentoxide (purity ≥ 99.5%) is transported to the melting furnace body 1 through the feeding device 3. After the powdered vanadium pentoxide is melted at high temperature, it flows out in a molten state to the discharging device 6 for cooling and collection.

[0030] Among them, the feeding device 3 includes a storage bin 31, a screw feeder 32, a rail trolley 30, and a dust collector 33. The storage bin 31, the screw feeder 32, and the dust collector 33 are all arranged on the rail trolley 30 to facilitate the overall movement and docking or separation with the melting furnace body 1. The storage bin 31 and the screw feeder 32 are both made of 304 stainless steel. The inner walls of the storage bin 31 and the conveying pipeline are sprayed with a tungsten carbide coating (not shown in the figure), and a vibrator (which can be purchased in the market, not shown in the figure) is provided on the side wall of the storage bin 31, which can effectively prevent the material from sticking to the wall and causing poor feeding. The dust collector 33 can timely remove the dust generated during the operation of the feeding device 3 (such as the vibration of the vibrator, the conveying of the screw feeder 32, etc.), and ensure the cleanliness of the environment where the equipment is located.

[0031] The powdered vanadium pentoxide is heated in multiple stages in the melting furnace body 1 in sequence, and finally flows out from the discharge slide 5 in a molten state. The furnace 10 is divided into two parts from right to left: a preheating zone 11 and a high-temperature zone 12. The preheating zone 11 and the high-temperature zone 12 are composed of multiple temperature zones, and adjacent temperature zones are separated by thermal insulation components 15 (such as pressureless sintered silicon carbide square beams, etc.). The furnace 10 is provided with multiple thermal insulation locks, and adopts step temperature control. The temperature difference is used to control the melting speed of vanadium pentoxide, ensure that the powdered vanadium pentoxide is fully melted, and avoid mixing of powdered vanadium pentoxide into the finished product. The bottom of the furnace 10 adopts a high-purity ceramic liner to prevent impurities from contaminating the vanadium pentoxide. Among them, the function of the preheating zone 11 is to accumulate the powdered vanadium pentoxide and melt the bottom layer. The set temperature is 500-700°C. By changing the temperature of each temperature zone in the preheating zone 11, the melting rate of the powdered vanadium pentoxide can be effectively controlled. In addition, the slope of the portion of the bottom of the furnace 10 corresponding to the preheating zone 11 is 10-15°, and its slope matches the viscosity coefficient of the molten vanadium pentoxide to prevent the bottom molten vanadium pentoxide from accumulating inside the furnace 10; Among them, the function of the high-temperature zone 12 is to fully melt the powdered vanadium pentoxide. The set temperature is 700-1000°C. The slope of the portion of the bottom of the furnace 10 corresponding to the high-temperature zone 12 is 5-10°. The set temperature of the high-temperature zone 12 is higher than that of the preheating zone 11, and the slope of the bottom of the furnace 10 is lower than that of the preheating zone 11. This not only prolongs the material residence time and ensures complete melting of the vanadium pentoxide, but also facilitates the control of the discharge rate of the molten vanadium pentoxide. The furnace 10 is heated by a resistance heating device 2, ensuring uniform temperature and high temperature control precision. This helps avoid the low vanadium recovery rate, easy caking, and high carbon content that are common in traditional melting furnaces. The melting furnace body 1 is equipped with multiple air inlets 13, one for each temperature zone. These multiple inlets allow sufficient oxygen to flow into the furnace 10, maintaining an oxidizing atmosphere and ensuring the purity of vanadium pentoxide within the furnace 10, while preventing the contamination of the product with low-priced vanadium. The function of the outlet heating device 4 is to assist heating. It is preferred to use an external heating alloy resistance wire for heating. The outer side of the alloy resistance wire uses high-quality polycrystalline mullite fiber material as an insulation layer with excellent insulation effect. The polycrystalline mullite fiber is fixed to the inner wall of the stainless steel shell. The outlet heating device 4 is set to a temperature of 500-800°C, which can effectively prevent the molten vanadium pentoxide from accumulating when it is cold at the discharge port; the discharge slide 5 is made of 316L stainless steel, and the surface is also sprayed with tungsten carbide coating. The slope is set to 5-10°, which is consistent with the slope of the bottom of the high-temperature zone 12 of the melting furnace body 1. Combined with the tungsten carbide coating on the inner wall, it can ensure that the molten vanadium pentoxide flows smoothly.

[0032] The function of the discharging device 6 is to water-cool the vanadium pentoxide in a molten state.

[0033] Although the present invention has been disclosed above in preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make many possible changes and modifications to the technical solution of the present invention by using the technical content disclosed above without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment with equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the scope of protection of the technical solution of the present invention.

Claims

1. An ultra-high purity tablet vanadium pentoxide production device, including a melting furnace body (1), characterized in that: Inside the furnace chamber (10) of the melting furnace body (1), there are a preheating zone (11) and a high-temperature zone (12). Both the preheating zone (11) and the high-temperature zone (12) include multiple temperature zones, and adjacent temperature zones are separated by heat-insulating components (15). Step temperature control is adopted, and the melting rate of vanadium pentoxide is controlled by the temperature difference to ensure that the powdered vanadium pentoxide is fully melted. The temperature of the preheating zone (11) is 500 - 700 °C, the slope at the bottom of the furnace chamber (10) corresponding to the preheating zone (11) is 10 - 15 °, the temperature of the high-temperature zone (12) is 700 - 1000 °C, the slope at the bottom of the furnace chamber (10) corresponding to the high-temperature zone (12) is 5 - 10 °. There is a resistance heating device (2) inside the furnace chamber (10). The heat-insulating component (15) is a non-pressure sintered silicon carbide square beam. On the other side of the melting furnace body (1), there is an outlet heating device (4) and a discharging slide plate (5). The discharging slide plate (5) is connected to a discharging device (6). The heating temperature of the outlet heating device (4) is 500 - 800 °C, and the slope of the discharging slide plate (5) is 5 - 10 °.

2. The ultra-high purity vanadium pentoxide tablet production equipment according to claim 1, characterized in that: There are multiple air inlets (13) provided on the melting furnace body (1), and each air inlet (13) is arranged in one-to-one correspondence with each temperature zone.

3. The ultra-high purity tablet vanadium pentoxide production equipment according to claim 1, characterized in that: There is a ceramic inner liner at the bottom of the furnace chamber (10).

4. The ultra-high purity tablet vanadium pentoxide production equipment according to any one of claims 1 to 3, characterized in that: On one side of the melting furnace body (1), there is a feeding device (3). The feeding device (3) includes a rail trolley (30), a storage bin (31) and a screw feeder (32) provided on the rail trolley (30). The screw feeder (32) is connected to the storage bin (31). Tungsten carbide coatings are provided on the inner wall of the storage bin (31) and the inner wall of the conveying pipe of the screw feeder (32). The storage bin (31) is also equipped with a vibrator.

5. The ultra-high purity vanadium pentoxide tablet production equipment according to any one of claims 1 to 3, characterized in that: The outlet heating device (4) includes alloy resistance wires and a polycrystalline mullite fiber material heat-insulating layer provided outside the alloy resistance wires. The inner wall of the discharging slide plate (5) is provided with a tungsten carbide coating.

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