Cyclone reactor for reducing tantalum and niobium oxides by using gaseous magnesium

Abstract

The utility model discloses a cyclone reactor for reducing tantalum and niobium oxides by using gaseous magnesium, which belongs to the technical field of metal reduction and comprises a barrel, a hexsteel and a wear-resistant lining. A plurality of inner lining plates are laid on the inner wall of the cylinder body, and the inner lining plates are connected with the cylinder body through bolts. The hexsteel is laid on the surfaces of the lining plates, and the hexsteel and the lining plates are fixed through self-piercing riveting. The hexsteel is filled with the wear-resistant lining. The hexsteel and wear-resistant lining structure is used for enhancing the wear resistance and corrosion resistance of the inner wall of the cyclone reactor cylinder. On the basis, structural transition is conducted between the hexsteel and the cylinder through the lining plate, the lining plate and the cylinder are detachably connected through the bolts, the lining protection structure is convenient to replace and maintain, and the situation that the whole cylinder needs to be replaced after the hexsteel and the abrasion-resistant lining lose efficacy is avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of metal reduction, in particular to a cyclone reactor for reducing tantalum and niobium oxides by using gaseous magnesium. Background Art

[0002] Tantalum and niobium, as rare metals, are widely used in the field of high-performance capacitor manufacturing due to their excellent physical and chemical properties. Therefore, how to economically and efficiently prepare tantalum and niobium metal powder materials has become an important research direction in this field. At present, the industrial preparation of tantalum and niobium usually adopts vacuum carbon reduction or metal thermal reduction. In the metal thermal reduction method, sodium is usually used as a reducing agent to reduce tantalum or niobium oxides to metals. However, the sodium reduction method has put tremendous pressure on environmental protection in the treatment of by-products (such as sodium fluoride, potassium fluoride, sodium chloride and potassium chloride), which has restricted the development of the sodium reduction method for producing tantalum and niobium metal powders.

[0003] Over the years, research on gaseous magnesium reduction technology has gradually become a hot topic. The core concept of this emerging process is to react tantalum oxide or niobium oxide with gaseous magnesium at high temperature and in an inert atmosphere (mostly argon) to directly obtain powdered metallic tantalum or niobium. Cyclones are introduced in this process to achieve efficient reaction and product separation. The working principle of a cyclone separator is based on the gas-solid separation process, separating heavier solid matter from the airflow through a high-speed rotating airflow.

[0004] Because magnesium reduction reactions typically occur in temperatures exceeding 1100°C to ensure proper reaction progress, the equipment's heat resistance is extremely demanding. Long-term operation in high-temperature environments, in particular, can lead to thermal fatigue and performance degradation of the material. Furthermore, within the cyclone separator, solid tantalum, niobium oxide, and gaseous magnesium frequently come into contact with the high-speed, rotating airflow and collide with the vessel walls. Long-term use can easily lead to wear and even corrosion of the wall material.

[0005] Currently, the most common method to address this problem is to weld a tortoise shell mesh inside the vessel wall, followed by a wear-resistant lining. While this method slows down the wear of the vessel wall, the welds between the tortoise shell mesh and the vessel wall are easily corroded into a powdery state, causing large areas of the tortoise shell mesh and wear-resistant lining to fall off, resulting in contamination of the finished product. Utility Model Content

[0006] The purpose of the utility model is to provide a cyclone reactor for reducing tantalum and niobium oxides with gaseous magnesium, so as to solve the problems raised in the above-mentioned prior art.

[0007] Provided is a cyclone reactor for reducing tantalum and niobium oxides using gaseous magnesium, comprising:

[0008] A cylinder, wherein a plurality of lining plates are laid on the inner wall of the cylinder, and the lining plates are connected to the cylinder by bolts;

[0009] Tortoise shell mesh, the tortoise shell mesh is laid on the surface of several inner lining plates, and the tortoise shell mesh and the inner lining plates are fixed by self-piercing riveting;

[0010] A wear-resistant lining is filled in the tortoise shell mesh.

[0011] Furthermore, an isolation pad is provided between the inner lining plate and the cylinder, which can fill the gap between the inner lining plate and the cylinder, preventing high temperature and corrosive substances from eroding the inner wall of the cylinder and enhancing the sealing effect.

[0012] Furthermore, a separation gap is provided between adjacent liner panels, and the isolation padding layer is filled into the separation gap between the two adjacent liner panels. Because the liner panels expand and contract when subjected to high and low temperature transitions, the separation gap provides space for expansion. Furthermore, because the separation gap can cause erosion by high temperatures and corrosive substances, filling the separation gap with the isolation padding layer enhances sealing.

[0013] Furthermore, the bolt holes on the inner lining plate are countersunk holes filled with an isolation pad. The countersunk holes can prevent the risk of exposure caused by the exposed bolts, and the isolation pad in the countersunk holes can further play an insulating role.

[0014] Furthermore, the isolation pad layer is made of ceramic fiber or carbon fiber cloth. Ceramic fiber and carbon fiber cloth are both resistant to high temperatures and corrosion, and have a certain degree of deformation ability. When located in the separation seam, they will not interfere with the expansion and contraction of the inner lining plate.

[0015] Furthermore, the wear-resistant lining is made of corundum or silicon carbide plastic. Both corundum and silicon carbide have high fire resistance and wear resistance, and can be used as plastic to fill the grid of the tortoise shell mesh and tightly bond with the tortoise shell mesh.

[0016] Furthermore, the wear-resistant lining is tantalum oxide ceramic or niobium oxide ceramic. Capacitor-grade tantalum powder or niobium powder requires extremely high purity and must not contain other impurities. Ceramics containing tantalum oxide or niobium oxide as the main body are less likely to increase impurities in the tantalum powder.

[0017] Furthermore, the cylinder comprises, from top to bottom, a top plate, a straight cylinder, and a conical cylinder. The inner lining plate, tortoise shell mesh, and wear-resistant lining are disposed on the inner wall of the conical cylinder. A heating source is disposed on the periphery of the straight cylinder. The cyclone reactor is generally subject to severe wear in the conical cylinder and top plate, and heating is required to maintain the reaction temperature during the reduction reaction of gaseous magnesium. Therefore, protective structures are only provided on the conical cylinder and top plate, while a contact heating source is disposed on the periphery of the straight cylinder.

[0018] Furthermore, the inner lining plate, tortoise shell mesh and wear-resistant lining are arranged on the inner wall of the top plate.

[0019] Furthermore, the outer wall of the cylinder extends outward from the inner wall where it is bolted to the inner liner plate to form a reinforcing rib. Limited by the cylinder's thickness, the depth of the threaded hole in the cylinder cannot be too large to avoid damaging the cylinder structure. Therefore, by increasing the thickness of this portion with the reinforcing rib, the depth of the threaded hole can be increased, thereby strengthening the cylinder.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] 1. The tortoise shell mesh and wear-resistant lining structure is used to enhance the wear and corrosion resistance of the inner wall of the cyclone reactor cylinder. On this basis, the tortoise shell mesh and the cylinder are connected by an inner lining plate as a structural transition. The inner lining plate and the cylinder are detachably connected by bolts, which facilitates the replacement and maintenance of the inner lining protection structure and avoids the need to replace the entire cylinder after the tortoise shell mesh and wear-resistant lining fail.

[0022] 2. The tortoise shell mesh and the inner lining plate are fixed by self-piercing riveting. Self-piercing riveting adopts cold processing method, which avoids the material performance degradation caused by the heat affected zone generated during welding, makes the connection point less susceptible to corrosion, and enhances the connection strength performance of the tortoise shell mesh.

[0023] 3. The riveting point of the tortoise shell mesh is on the inner lining plate, which avoids the damage of the cylinder structure caused by direct riveting between the tortoise shell mesh and the cylinder, and maintains the structural integrity of the cylinder. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present drawings or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present drawings. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0025] Figure 1 Schematic diagram of the overall structure of the cyclone reactor;

[0026] Figure 2 A layered arrangement diagram of the side wall of the cylinder provided by the present invention;

[0027] Figure 3 This is a partial cross-sectional view of the cylinder provided by the utility model.

[0028] In the figure: 1. Cylinder; 11. Top plate; 12. Straight cylinder; 13. Conical cylinder; 2. Tortoise shell mesh; 3. Wear-resistant lining; 4. Inner lining plate; 5. Isolation pad; 6. Separation seam; 7. Heating source; 8. Reinforcement ribs. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the present application is described and illustrated below in conjunction with the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely used to explain this application and are not intended to limit this application. Based on the embodiments provided in this application, all other embodiments obtained by those of ordinary skill in the art without making any creative efforts are within the scope of protection of this application.

[0030] Obviously, the drawings described below are merely examples or embodiments of the present application. Those skilled in the art can, without inventive effort, apply the present application to other similar scenarios based on these drawings. Furthermore, it is also understood that, although the effort involved in such a development process may be complex and lengthy, for those skilled in the art related to the content disclosed in this application, changes in design, manufacturing, or production based on the technical content disclosed in this application are merely conventional technical means and should not be construed as an insufficiency of the content disclosed in this application.

[0031] However, unnecessary detailed descriptions may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of substantially identical structures may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate understanding by those skilled in the art. Furthermore, the drawings and the following description are provided to facilitate a thorough understanding of this application by those skilled in the art and are not intended to limit the subject matter recited in the claims.

[0032] See also Figure 1-3 As shown in the figure, in an embodiment of the present invention, a cyclone reactor for reducing tantalum and niobium oxides using gaseous magnesium comprises a cylinder 1, a tortoise shell mesh 2, and a wear-resistant lining 3. The inner wall of the cylinder 1 is provided with a plurality of inner lining plates 4, which are bolted to the cylinder 1. The tortoise shell mesh 2 is laid on the surface of the plurality of inner lining plates 4 and secured to the inner lining plates 4 by self-piercing riveting. The wear-resistant lining 3 is filled within the tortoise shell mesh 2.

[0033] The inner lining plate 4 is laid on the inner wall of the cylinder 1 in a modular form. Corresponding threaded holes are opened on the cylinder 1 and the inner lining plate 4 and are connected by bolts. After the inner lining plate 4 is laid, the tortoise shell mesh 2 is laid on the inner lining plate 4. The bottom of the tortoise shell mesh 2 is integrally formed with a connecting piece, and is fixed by self-piercing riveting between the connecting piece and the inner lining plate 4. Since self-piercing riveting is a cold working method, there will be no heat-affected zone between the tortoise shell mesh 2 and the inner lining plate 4, which will lead to a decrease in corrosion resistance, and the connection strength is high and it is not easy to fall off. In addition, the deformation of the inner lining plate 4 caused by the rivets will not penetrate into the cylinder 1, maintaining the structural integrity of the cylinder 1. The tortoise shell mesh 2 serves as a structural frame to fix the wear-resistant lining 3. The wear-resistant lining 3 has high temperature resistance, corrosion resistance and wear resistance, and is used to resist the mixed erosion of gaseous magnesium, oxide materials and inert gas, which significantly improves the service life of the cyclone reactor and provides a stable and efficient reaction vessel for gaseous magnesium to reduce tantalum and niobium oxides.

[0034] Specifically, an isolation pad 5 is provided between the inner lining plate 4 and the cylinder 1. The isolation pad 5 can be specifically ceramic fiber or carbon fiber cloth, which has high temperature resistance, corrosion resistance and plasticity. The inner lining plate 4 and the cylinder 1 are limited by the processing accuracy and the influence of deformation. It is inevitable that there is a local gap between the two when they are assembled, which leads to the invasion of high temperature and corrosive substances, causing erosion of the cylinder 1 and the bolts. In addition, considering the assembly problem, the inner lining plate 4 is arranged on the inner wall of the cylinder 1 in a modular form, and there is a gap between two adjacent inner lining plates 4, which also leads to the invasion of high temperature and corrosive substances. Therefore, the deformation of the isolation pad 5 can eliminate the gap between the two, avoid the contact of high temperature and corrosive substances with the cylinder 1, and form a complete sealing protection.

[0035] Furthermore, considering the thermal expansion of the inner lining panels 4, the gap between adjacent inner lining panels 4 needs to be enlarged to form a separation gap 6 to provide expansion space. Therefore, an isolation pad 5 is filled into the separation gap 6 between adjacent inner lining panels 4. Specifically, the isolation pad 5 can be partially folded at the separation gap 6 to maintain the integrity of the isolation pad 5.

[0036] The bolt holes in the inner liner 4 are countersunk. After the bolts connect the inner liner 4 to the cylinder 1, the bolt heads sink into the countersunk holes, preventing interference between the bolts and the wear-resistant liner 3 while also minimizing the risk of bolt exposure. The countersunk holes are filled with an isolation pad 5, which can be made of ceramic fiber or carbon fiber cloth, to isolate the bolts from the outside world. This reduces the risk of erosion from high-temperature atmospheres and material abrasion, preventing damage to the bolts and threaded holes.

[0037] The wear-resistant lining 3 can be made of corundum or silicon carbide plastic. Corundum has a long-term operating temperature of 1800°C and does not readily bond with molten metal. Silicon carbide has a long-term operating temperature of over 1500°C. Both materials have extremely high wear resistance and can effectively resist material erosion.

[0038] The wear-resistant lining 3 can be made of tantalum oxide ceramic or niobium oxide ceramic, which is filled within the mesh of the tortoise shell mesh 2 and tightly bonded to the tortoise shell mesh 2. Even if the wear-resistant lining 3 of tantalum oxide ceramic or niobium oxide ceramic partially falls off, it can participate in the reduction reaction, reducing the impurity content in the tantalum powder or niobium powder.

[0039] The outer wall of the cylinder 1 extends outward from the inner wall portion where it is bolted to the inner liner 4 to form reinforcing ribs 8. Limited by the thickness of the cylinder 1 itself, the threaded connection depth between the bolts and the cylinder 1 is too small without the bolts penetrating the cylinder 1 wall, which is not conducive to maintaining structural stability. Furthermore, the fact that this portion of the cylinder 1 is penetrated by the bolts increases the risk of corrosion. The purpose of the reinforcing ribs 8 is to increase the thickness of this portion of the cylinder 1 wall, allowing the bolts to have sufficient threading depth and ensuring that the cylinder 1 is thick enough to maintain its inherent strength.

[0040] In actual applications, it was found that the cyclone reactor's conical body 13 and top plate 11 were severely corroded. The conical body 13's conical necking increased the material's scouring velocity, density, and intensity, while the top plate 11 easily caused particles to aggregate, forming a top ash ring. Therefore, only the protective structure consisting of the inner lining plate 4, the tortoise shell mesh 2, and the wear-resistant lining 3 was set on the inner walls of the conical body 13 and the top plate 11. Since the straight cylindrical body 12 needs to maintain the reaction temperature during the reduction reaction of gaseous magnesium, it needs to be temperature-controlled by the heating source 7. Therefore, the heating source 7 is set on the periphery of the straight cylindrical body 12.

[0041] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are merely examples, and any embodiments having substantially the same structure and effect as the technical concept within the scope of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the present application, any other embodiments that can be conceived by those skilled in the art and that combine some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A cyclone reactor for reducing tantalum and niobium oxides using gaseous magnesium, characterized in that: include: A cylinder (1), wherein a plurality of inner lining plates (4) are laid on the inner wall of the cylinder (1), and the inner lining plates (4) are connected to the cylinder (1) by bolts; A tortoise shell net (2), the tortoise shell net (2) being laid on the surface of a plurality of inner lining plates (4), the tortoise shell net (2) and the inner lining plates (4) being fixed by self-piercing riveting; A wear-resistant lining (3) is filled in the tortoise shell mesh (2).

2. A cyclone reactor for reducing tantalum and niobium oxides with gaseous magnesium according to claim 1, characterized in that: An isolation cushion layer (5) is provided between the inner lining plate (4) and the cylinder (1).

3. A cyclone reactor for reducing tantalum and niobium oxides with gaseous magnesium according to claim 2, characterized in that: A separation gap (6) is provided between two adjacent inner lining plates (4), and the isolation pad layer (5) is filled into the separation gap (6) between the two adjacent inner lining plates (4).

4. A cyclone reactor for reducing tantalum and niobium oxides with gaseous magnesium according to claim 1, characterized in that: The bolt holes on the inner lining plate (4) are countersunk holes, and the countersunk holes are filled with an isolation cushion layer (5).

5. A cyclone reactor for reducing tantalum and niobium oxides with gaseous magnesium according to any one of claims 2 to 4, characterized in that: The isolation pad layer (5) is ceramic fiber or carbon fiber cloth.

6. The cyclone reactor for reducing tantalum and niobium oxides with gaseous magnesium according to claim 1, characterized in that: The wear-resistant lining (3) is corundum or silicon carbide plastic.

7. The cyclone reactor for reducing tantalum and niobium oxides with gaseous magnesium according to claim 1, characterized in that: The wear-resistant lining (3) is tantalum oxide ceramic or niobium oxide ceramic.

8. The cyclone reactor for reducing tantalum and niobium oxides with gaseous magnesium according to claim 1, characterized in that: The cylinder (1) comprises a top plate (11), a straight cylinder (12) and a conical cylinder (13) arranged in sequence from top to bottom; the inner lining plate (4), the tortoise shell mesh (2) and the wear-resistant lining (3) are arranged on the inner wall of the conical cylinder (13); and a heating source (7) is arranged on the periphery of the straight cylinder (12).

9. A cyclone reactor for reducing tantalum and niobium oxides with gaseous magnesium according to claim 8, characterized in that: The inner lining plate (4), the tortoise shell mesh (2) and the wear-resistant lining (3) are arranged on the inner wall of the top plate (11).

10. The cyclone reactor for reducing tantalum and niobium oxides with gaseous magnesium according to claim 1, characterized in that: The outer wall of the cylinder (1) extends outward relative to the inner wall portion that is bolted to the inner lining plate (4) to form a reinforcing rib (8).

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