Material conveying device for ferrous oxalate production

Abstract

The application provides a material conveying device for ferrous oxalate production, which comprises a storage tank and a main conveying pipe, the storage tank is communicated with the main conveying pipe, both ends of the main conveying pipe are respectively connected with a blower and an explosion-proof electric valve, the explosion-proof electric valve is connected with a secondary conveying pipe, the secondary conveying pipe is connected with a to-be-fed tank, detectors are arranged on the main conveying pipe, the secondary conveying pipe and the to-be-fed tank, a circulating pipe is arranged on the upper end of the outer side wall of the to-be-fed tank, a filter screen is arranged on the inner side wall of the to-be-fed tank, a dismounting mechanism is arranged on the to-be-fed tank, an explosion-proof pipe and a first explosion-proof air valve are arranged on the circulating pipe, a second explosion-proof air valve is arranged on the explosion-proof pipe, a dust treatment mechanism is arranged on the end of the explosion-proof pipe far from the circulating pipe, when the dust concentration exceeds the safety limit value or the oxygen concentration abnormally rises, the dust treatment mechanism sucks in and treats the dust through the circulating pipe and the explosion-proof pipe, and the occurrence of dust explosion accidents is effectively prevented.

Description

Technical Field

[0001] This application relates to the field of ferrous oxalate production, and more specifically, to a material conveying device for ferrous oxalate production. Background Technology

[0002] Ferrous oxalate is a pale yellow crystalline powder. As a key precursor for the manufacture of lithium iron phosphate, the cathode material of lithium-ion batteries, its purity typically requires a total impurity content of less than 100 ppm and a particle size (D50) within the range of 5-10 μm. The morphology and purity of the powder directly affect the battery's charge-discharge efficiency, rate performance, and cycle life. In addition, ferrous oxalate is widely used in dyes, coatings, ceramics, glassware colorants, novel photosensitive materials, and the synthesis of nanomagnetic materials.

[0003] Material conveying is a crucial step in the production of ferrous oxalate. Due to the extremely fine particle size and low bulk density of ferrous oxalate powder, it easily generates dust and suspended dust clouds during transport. More importantly, ferrous oxalate powder is combustible dust; when mixed with air or other combustible gases to reach a certain concentration, it can easily trigger a dust explosion if an ignition source is present. During pneumatic conveying, the dust in the pipeline is in a suspended state, already meeting the main conditions for a dust explosion. If static electricity accumulates or sparks ignite, it could lead to a major safety accident and potentially cause a secondary explosion.

[0004] Furthermore, ferrous oxalate has strong reducing properties. If it comes into prolonged contact with oxygen in the air during transportation, it is easily oxidized to ferric iron, causing the product to change from pale yellow to brown or even black, significantly reducing its purity and failing to meet the high purity requirements of battery-grade products. Existing pneumatic conveying devices for ferrous oxalate generally suffer from the following shortcomings: firstly, they lack real-time monitoring methods for dust and oxygen concentrations during transportation, making it difficult to provide timely warnings when dust concentrations exceed standards; secondly, most systems are open designs, allowing for direct emission of dust-laden gas, resulting in both material loss and environmental pollution. Summary of the Invention

[0005] This application aims to address at least one of the technical problems existing in the prior art or related technologies.

[0006] Therefore, the first aspect of this application is to provide a material conveying device for the production of ferrous oxalate.

[0007] In view of the above, according to the first aspect of this application, a material conveying device for ferrous oxalate production is provided, including a storage tank and a main conveying pipe. The outlet of the storage tank is connected to the side wall of the main conveying pipe. A blower and an explosion-proof electric valve are respectively connected to both ends of the main conveying pipe. A secondary conveying pipe is connected to the end of the explosion-proof electric valve away from the main conveying pipe. A feed tank is connected to the end of the secondary conveying pipe away from the explosion-proof electric valve. Detectors for testing dust concentration and oxygen concentration are provided on the main conveying pipe, the secondary conveying pipe, and the feed tank. A circulation pipe is provided at the upper end of the outer wall of the feed tank. A filter screen for filtering the gas entering the circulation pipe is provided on the inner wall of the feed tank. A filter screen removal and installation mechanism is provided on the feed tank. An explosion-proof pipe and a first explosion-proof gas valve are sequentially provided on the circulation pipe. A second explosion-proof gas valve is provided on the explosion-proof pipe. A dust treatment mechanism is provided at the end of the explosion-proof pipe away from the circulation pipe.

[0008] In one possible technical solution, the disassembly and assembly mechanism further includes a magnetic holding electromagnet for magnetically holding the filter screen, the magnetic holding electromagnet being disposed on the outer side wall of the feed tank.

[0009] In one possible technical solution, the filter screen is further provided with a first permanent magnet that is magnetically attracted to the magnetic holding electromagnet, and the side wall of the feed tank is provided with a second permanent magnet that is repelled by the first permanent magnet. The repulsive force between the second permanent magnet and the first permanent magnet is less than the magnetic attraction force between the magnetic holding electromagnet and the first permanent magnet.

[0010] In one possible technical solution, an insulating protective box is further provided on the outer wall of the feed tank, and the second permanent magnet and the magnetic holding electromagnet are both disposed inside the protective box. The protective box is provided with a partition to isolate the magnetic forces of the second permanent magnet and the magnetic holding electromagnet.

[0011] In one possible technical solution, the filter screen further includes a frame and a filter media screen. Both the frame and the first permanent magnet are annular structures. The first permanent magnet is embedded on the surface of the frame opposite to the magnetic holding electromagnet. The first permanent magnet is concentric with the frame. The surface of the frame opposite to the magnetic holding electromagnet abuts against the inner wall of the feeding tank. The circulation pipe is inserted into the inner ring of the frame. The filter media screen is installed inside the ring of the frame at a position opposite to the circulation pipe.

[0012] In one possible technical solution, the dust treatment mechanism further includes a treatment tank containing pure water, an explosion-proof pipe inserted into the pure water in the treatment tank, an explosion-proof fan installed on the explosion-proof pipe to send the dust into the pure water, and an exhaust pipe installed at the top of the treatment tank.

[0013] In one possible technical solution, the secondary conveying pipe further includes multiple sub-conveying pipes, which are connected sequentially.

[0014] In one possible technical solution, each of the sub-conveying pipes is further provided with a detector.

[0015] In one possible technical solution, the detector further includes a mounting base, one end of which extends into the main conveying pipe, the auxiliary conveying pipe, or the feed tank. A dust concentration sensor and an oxygen concentration sensor are disposed inside the mounting base, and the sensing ends of the dust concentration sensor and the oxygen concentration sensor are exposed from the extension end of the mounting base.

[0016] In one possible technical solution, furthermore, both the inner wall of the main conveying pipe and the inner wall of the auxiliary conveying pipe are provided with wear-resistant and corrosion-resistant linings.

[0017] The beneficial effects of this invention are as follows: This device is equipped with detectors on the main conveying pipe, the auxiliary conveying pipe, and the feeding tank. These detectors monitor the dust and oxygen concentrations in the main conveying pipe, the auxiliary conveying pipe, and the feeding tank in real time. When the dust concentration exceeds the safety limit or the oxygen concentration rises abnormally, corresponding measures are taken to effectively prevent dust explosion accidents.

[0018] Corresponding measures include: when only the dust concentration is close to or exceeds the safety limit, the blower reduces its airflow to reduce dust; when both dust and oxygen concentrations reach the safety limit, or only the oxygen concentration reaches the safety limit, the blower stops, the explosion-proof electric valve closes, the disassembly mechanism removes the filter screen, the first explosion-proof valve closes, the second explosion-proof valve opens, and the dust treatment mechanism draws in and treats the dust through the circulation pipe and the explosion-proof pipe, thereby preventing dust explosions; when the dust concentration reaches a safe value, the conveying device stops, and the location of any leaks is located and repaired. Simultaneously, the feed tank is equipped with a filter screen disassembly mechanism, allowing users to easily remove the filter screen from the inner wall of the feed tank for cleaning or replacement. This solves the problem of easy clogging and difficult cleaning of filters in existing technologies, reduces equipment maintenance costs, and ensures the smooth flow of the circulation pipeline and the long-term stable operation of the system. A circulation pipe is installed on the upper part of the outer wall of the feeding tank, which is connected to the inside of the feeding tank. A filter screen is installed on the inner wall of the feeding tank to filter the gas entering the circulation pipe. The filtered gas can be returned to the system for reuse through the circulation pipe, realizing closed-loop gas circulation. This reduces the loss of materials caused by airflow and avoids the pollution caused by the direct emission of dust-laden gas. Attached Figure Description

[0019] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the overall structure of this embodiment; Figure 2 for Figure 1 Enlarged cross-sectional structural diagram of region A in the middle; Figure 3 for Figure 1 Enlarged cross-sectional structural diagram of region B in the middle.

[0020] Reference numerals: 1. Storage tank; 10. Main conveying pipe; 11. Blower; 12. Explosion-proof electric valve; 2. Secondary conveying pipe; 20. Sub-conveying pipe; 3. Feeding tank; 4. Detector; 40. Mounting base; 41. Dust concentration sensor; 42. Oxygen concentration sensor; 5. Circulation pipe; 50. Explosion-proof pipe; 51. First explosion-proof valve; 52. Second explosion-proof valve; 6. Filter screen; 60. Frame; 61. Filter media; 7. Magnetic holding electromagnet; 70. First permanent magnet; 71. Second permanent magnet; 72. Protective box; 73. Partition; 8. Processing box; 80. Explosion-proof fan; 81. Exhaust pipe; 9. Corrosion-resistant lining. Detailed Implementation

[0021] To better understand the above-mentioned objectives, features, and advantages of this application, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0022] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0023] The following reference Figures 1 to 3 This application describes a material conveying device for ferrous oxalate production according to some embodiments.

[0024] Example A material conveying device for ferrous oxalate production includes a storage tank 1 and a main conveying pipe 10. The outlet of the storage tank 1 is connected to the side wall of the main conveying pipe 10. A blower 11 and an explosion-proof electric valve 12 are respectively connected to both ends of the main conveying pipe 10. A secondary conveying pipe 2 is connected to the end of the explosion-proof electric valve 12 away from the main conveying pipe 10. A feed tank 3 is connected to the end of the secondary conveying pipe 2 away from the explosion-proof electric valve 12. Detectors 4 for testing dust concentration and oxygen concentration are installed on the main conveying pipe 10, the secondary conveying pipe 2, and the feed tank 3. The outer wall of the feed tank 3... A circulation pipe 5 is provided at one end. A filter screen 6 is provided on the inner wall of the feeding tank 3 to filter the gas entering the circulation pipe 5. The dust-laden gas in the feeding tank 3 flows upward under pressure. After being filtered by the filter screen 6, the ferrous oxalate dust is intercepted inside the feeding tank 3, and the clean gas enters the circulation pipe 5. The gas in the circulation pipe 5 can be returned to the blower 11 for reuse via the first explosion-proof valve 51. The feeding tank 3 is provided with a disassembly and assembly mechanism for the filter screen 6. An explosion-proof pipe 50 and a first explosion-proof valve 51 are sequentially provided on the circulation pipe 5. A second explosion-proof valve 50 is provided on the explosion-proof pipe 50. 2. A dust treatment mechanism is provided at the end of the explosion-proof pipe 50 away from the circulation pipe 5. Ferrous oxalate powder is stored in the storage tank 1. When the blower 11 and the explosion-proof electric valve 12 are turned on, the compressed gas generated by the blower 11 sends the ferrous oxalate powder falling from the outlet of the storage tank 1 along the main conveying pipe 10, the explosion-proof electric valve 12, and the auxiliary conveying pipe 2 into the waiting-to-feed tank 3. The ferrous oxalate powder in the waiting-to-feed tank 3 awaits entry into the subsequent production process. Detectors 4 are installed on the main conveying pipe 10, the auxiliary conveying pipe 2, and the waiting-to-feed tank 3 to monitor the dust concentration and oxygen concentration inside the pipes and the waiting-to-feed tank 3 in real time. When any detector 4 detects that only the dust concentration is close to or exceeds the safety limit, the blower 11 reduces the airflow to reduce dust. When any detector 4 detects that both the dust concentration and oxygen concentration have reached the safety limit, or only the oxygen concentration has reached the safety limit, the control device issues an alarm and automatically shuts off the blower 11 and the explosion-proof electric valve 12, cutting off the conveying. The control device is an existing industrial control computer. At the same time, the control device controls the disassembly mechanism to remove the filter screen 6, open the second explosion-proof gas valve 52, and close the first explosion-proof gas valve 51, introducing the gas and dust into the dust treatment mechanism at the end of the explosion-proof pipe 50 for harmless treatment. Furthermore, when the filter screen 6 needs to be cleaned or replaced after long-term use, it can be easily removed from the inner wall of the feed tank 3 through the disassembly mechanism, and reinstalled after maintenance.

[0025] Furthermore, such as Figure 1 and Figure 3As shown, the disassembly and assembly mechanism includes a magnetically holding electromagnet 7 for magnetically attracting the filter screen 6. The magnetically holding electromagnet 7 is disposed on the outer wall of the feeding tank 3. A magnetically holding electromagnet 7 is fixedly installed on the outer wall of the feeding tank 3 at the position corresponding to the filter screen 6. When the filter screen 6 needs to be fixed, the magnetically holding electromagnet 7 uses magnetic attraction to firmly attract the filter screen 6 to the tank wall of the feeding tank 3. The magnetic attraction of the magnetically holding electromagnet 7 is sufficient to firmly attract the filter screen 6 through the side wall of the feeding tank 3. When the filter screen 6 needs to be removed, the magnetically holding electromagnet 7 is energized, the magnetic force of the magnetically holding electromagnet 7 is canceled out, thereby releasing the filter screen 6, which falls off under the action of gravity. The magnetically holding electromagnet 7 only consumes power when switching states; it does not consume power when maintaining the magnetic attraction state for a long time, ensuring high safety and preventing continuous heating or sparks.

[0026] Furthermore, such as Figure 1 and Figure 3 As shown, the filter screen 6 is provided with a first permanent magnet 70 that is magnetically attracted to the magnetic holding electromagnet 7, and a second permanent magnet 71 that is repelled by the first permanent magnet 70 is provided on the side wall of the feeding tank 3. That is, the magnetic pole direction of the second permanent magnet 71 is set to be the same as that of the first permanent magnet 70, so that a repulsive force is generated between them. The repulsive force between the second permanent magnet 71 and the first permanent magnet 70 is less than the magnetic attraction force between the magnetic holding electromagnet 7 and the first permanent magnet 70. That is, when the magnetic holding electromagnet 7 is de-energized, the attraction force of the magnetic holding electromagnet 7 on the first permanent magnet 70 can attract the filter screen 6 to the tank wall of the feeding tank 3, ensuring that the filter screen 6 is firmly pressed against the tank wall, achieving sealing and fixation. When the magnetic holding electromagnet 7 is energized, the magnetic force of the magnetic holding electromagnet 7 is canceled out, and the repulsive force between the second permanent magnet 71 and the first permanent magnet 70 pushes the filter screen 6 away from the tank wall, making it easy for the operator to remove the filter screen 6 by hand or tool.

[0027] Furthermore, such as Figure 1 and Figure 3 As shown, an insulating protective box 72 is provided on the outer wall of the feeding tank 3. The protective box 72 is made of non-magnetic material, such as stainless steel or engineering plastic, and is fixed to the outer wall of the feeding tank 3. The second permanent magnet 71 and the magnetic holding electromagnet 7 are both set inside the protective box 72. The protective box 72 completely covers the magnetic holding electromagnet 7 and the second permanent magnet 71 for protection, preventing external metal debris from being attracted and avoiding direct contact between operators and electromagnets. In addition, the protective box 72 also serves to prevent dust, explosion and electrical insulation. The protective box 72 is provided with a partition 73 that isolates the magnetic force of the second permanent magnet 71 and the magnetic holding electromagnet 7. The partition 73 is made of soft iron or silicon steel sheet with high magnetic permeability. The partition 73 can block the magnetic lines of force between the two and avoid mutual interference.

[0028] Furthermore, such as Figure 1 and Figure 3As shown, the filter screen 6 includes a frame 60 and a filter media 61. The mesh size of the filter media 61 is selected according to the particle size of the ferrous oxalate powder. Both the frame 60 and the first permanent magnet 70 are annular structures. The frame 60 is made of corrosion-resistant metal or plastic, and its overall shape is circular. The inner diameter of the frame 60 matches the outer diameter of the circulation pipe 5. The first permanent magnet 70 is embedded on the surface of the frame 60 opposite to the magnetic holding electromagnet 7. That is, the first permanent magnet 70 is also made into a circular shape and is embedded in the surface of the frame 60 facing the side wall of the feeding tank 3 by bonding or injection molding. The first permanent magnet 70 is concentric with the frame 60. The surface of the magnet 7 facing the magnetic holding electromagnet 0 abuts against the inner wall of the feed tank 3. The circulation pipe 5 is inserted into the inner ring of the frame 60. The filter screen 61 is installed in the ring of the frame 60 at the position opposite to the circulation pipe 5. That is, the filter screen 61 is fixed in the inner ring of the frame 60 facing the inside of the feed tank 3. During installation, the end of the circulation pipe 5 passes through the side wall of the feed tank 3 and is inserted into the inner ring of the frame 60, thereby playing a role in centering and guiding the frame 60. When the gas flows from the inside of the feed tank 3 to the circulation pipe 5, it must pass through the filter screen 61. Ferrous oxalate dust is trapped on the outside of the filter screen 61, and clean gas enters the circulation pipe 5.

[0029] Furthermore, such as Figure 1 As shown, the dust treatment mechanism includes a treatment tank 8 filled with pure water. The treatment tank 8 is a sealed container. Preferably, the liquid level of the pure water is about two-thirds of the tank's height. The explosion-proof pipe 50 is inserted into the pure water in the treatment tank 8, with its end inserted from the top of the treatment tank 8 and extending below the liquid surface. An explosion-proof fan 80 is installed on the explosion-proof pipe 50 to deliver dust into the pure water. An exhaust pipe 81 is installed at the top of the treatment tank 8, and its end can be equipped with multiple air outlets or microporous aeration heads. When the second explosion-proof valve 52 is opened and the explosion-proof fan 80 is started, the dust-laden gas is forced into the pure water. The ferrous oxalate dust in the gas is captured by the pure water and settles at the bottom of the tank, thereby reducing the dust concentration and preventing dust explosion. The purified gas rises above the liquid surface in the form of bubbles and is discharged through the exhaust pipe 81 at the top of the treatment tank 8. The outlet of the exhaust pipe 81 can be further connected to an activated carbon filter or directly discharged into the atmosphere.

[0030] Furthermore, such as Figure 1As shown, the secondary conveying pipe 2 includes multiple branch conveying pipes 20, which are connected sequentially. Depending on the site layout requirements, the secondary conveying pipe 2 often needs to bypass obstacles or traverse long distances. Therefore, the secondary conveying pipe 2 is designed as multiple branch conveying pipes 20 connected end to end by flanges or quick couplings. In this embodiment, multiple branch conveying pipes 20 are connected end to end by flanges. The length of each branch conveying pipe 20 is determined based on the convenience of transportation and on-site installation. The flange connection between the branch conveying pipes 20 uses sealing gaskets to ensure airtightness, and the connection of the branch conveying pipes 20 is anti-static bridging. At the same time, the split structure of the secondary conveying pipe 2 also facilitates the partial replacement of worn or blocked pipe sections, reducing maintenance costs.

[0031] Furthermore, such as Figure 1 and Figure 2 As shown, each of the sub-conveying pipes 20 is equipped with a detector 4. Each detector 4 can independently monitor the dust concentration and oxygen concentration inside the corresponding sub-conveying pipe 20. Once a section of the sub-conveying pipe 20 leaks or gets blocked, causing an abnormal increase in dust concentration, the control system can accurately locate the fault location, facilitating rapid troubleshooting and handling. At the same time, the data from multiple detectors 4 can be cross-checked to improve the reliability of monitoring.

[0032] Furthermore, such as Figure 1 and Figure 2 As shown, the detector 4 includes a mounting base 40, one end of which extends into the main conveying pipe 10, the auxiliary conveying pipe 2, or the feed tank 3. A dust concentration sensor 41 and an oxygen concentration sensor 42 are installed inside the mounting base 40. The sensing ends of both the dust concentration sensor 41 and the oxygen concentration sensor 42 protrude from the extension end of the mounting base 40. The mounting base 40 is made of metal or corrosion-resistant plastic. A mounting hole is provided at the bottom of the mounting base 40. The dust concentration sensor 41 and the oxygen concentration sensor 42 are fixed side by side in the mounting hole, with their probes protruding from the extension end of the mounting base 40 and directly contacting the gas flow being measured. The dust concentration sensor 41 is a light scattering or charge induction miniature sensor, and the oxygen concentration sensor 42 is an electrochemical or zirconium oxide sensor. The signal lines of the sensors are led out from the outside of the mounting base 40 and connected to an industrial control computer. Sealant is filled between the mounting base 40 and the sensors to prevent gas leakage.

[0033] Furthermore, such as Figure 1 and Figure 2As shown, wear-resistant and corrosion-resistant linings 9 are provided on the inner walls of both the main conveying pipe 10 and the auxiliary conveying pipe 2. Since ferrous oxalate powder abrades the pipe wall under high-speed airflow, and ferrous oxalate itself and residual acidic substances may corrode ordinary carbon steel, a layer of wear-resistant and corrosion-resistant lining 9 is laminated on the inner walls of both the main conveying pipe 10 and the auxiliary conveying pipe 2. The lining material 9 is preferably alumina ceramic, polytetrafluoroethylene, or ultra-high molecular weight polyethylene. In this embodiment, the lining material 9 is alumina ceramic. The alumina ceramic lining is fixed to the inner wall of the steel pipe by pasting or centrifugal casting, and it has high hardness and good wear resistance.

[0034] In this application, the term "multiple" refers to two or more unless otherwise expressly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0035] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0036] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A material conveying device for the production of ferrous oxalate, characterized in that, The system includes a storage tank and a main conveying pipe. The outlet of the storage tank is connected to the side wall of the main conveying pipe. A blower and an explosion-proof electric valve are connected to both ends of the main conveying pipe, respectively. A secondary conveying pipe is connected to the end of the explosion-proof electric valve away from the main conveying pipe. A feed tank is connected to the end of the secondary conveying pipe away from the explosion-proof electric valve. Detectors for testing dust concentration and oxygen concentration are installed on the main conveying pipe, the secondary conveying pipe, and the feed tank. A circulation pipe is installed at the upper end of the outer wall of the feed tank. A filter screen for filtering the gas entering the circulation pipe is installed on the inner wall of the feed tank. A filter screen removal and installation mechanism is installed on the feed tank. An explosion-proof pipe and a first explosion-proof gas valve are sequentially installed on the circulation pipe. A second explosion-proof gas valve is installed on the explosion-proof pipe. A dust treatment mechanism is installed at the end of the explosion-proof pipe away from the circulation pipe.

2. The material conveying device for ferrous oxalate production according to claim 1, characterized in that, The disassembly and assembly mechanism includes a magnetic holding electromagnet for magnetically holding the filter screen; the magnetic holding electromagnet is disposed on the outer wall of the feed tank.

3. The material conveying device for ferrous oxalate production according to claim 2, characterized in that, The filter screen is provided with a first permanent magnet that is magnetically attracted to the magnetic holding electromagnet; the side wall of the feeding tank is provided with a second permanent magnet that is repelled by the first permanent magnet; the repulsive force between the second permanent magnet and the first permanent magnet is less than the magnetic attraction force between the magnetic holding electromagnet and the first permanent magnet.

4. The material conveying device for ferrous oxalate production according to claim 3, characterized in that, An insulated protective box is provided on the outer wall of the feed tank; the second permanent magnet and the magnetic holding electromagnet are both placed inside the protective box; a partition is provided inside the protective box to isolate the magnetic force of the second permanent magnet and the magnetic holding electromagnet.

5. A material conveying device for ferrous oxalate production according to claim 3, characterized in that, The filter screen includes a frame and a filter media screen; both the frame and the first permanent magnet are annular structures; the first permanent magnet is embedded in the frame on the surface opposite to the magnetic holding electromagnet; the first permanent magnet is concentric with the frame; the surface of the frame opposite to the magnetic holding electromagnet abuts against the inner wall of the feeding tank; the circulation pipe is inserted into the inner ring of the frame; the filter media screen is installed inside the ring of the frame at a position opposite to the circulation pipe.

6. The material conveying device for ferrous oxalate production according to claim 1, characterized in that, The dust treatment mechanism includes a treatment tank containing pure water; an explosion-proof pipe is inserted into the pure water in the treatment tank; an explosion-proof fan is installed on the explosion-proof pipe to send the dust into the pure water; and an exhaust pipe is installed at the top of the treatment tank.

7. The material conveying device for ferrous oxalate production according to claim 1, characterized in that, The secondary conveying pipe includes multiple branch conveying pipes; the multiple branch conveying pipes are connected in sequence.

8. A material conveying device for ferrous oxalate production according to claim 7, characterized in that, Each of the aforementioned delivery pipes is equipped with a detector.

9. A material conveying device for ferrous oxalate production according to claim 1, characterized in that, The detector includes a mounting base; one end of the mounting base extends into the main conveying pipe, the auxiliary conveying pipe, or the feed tank; a dust concentration sensor and an oxygen concentration sensor are installed inside the mounting base; the sensing ends of the dust concentration sensor and the oxygen concentration sensor are exposed from the extension end of the mounting base.

10. A material conveying device for ferrous oxalate production according to claim 1, characterized in that, The inner walls of both the main conveying pipe and the auxiliary conveying pipe are lined with wear-resistant and corrosion-resistant materials.

Images