Waste lithium iron phosphate battery recycling process

Abstract

The invention provides a waste lithium iron phosphate battery recycling process, and belongs to the technical field of lithium iron phosphate battery recycling. Comprising a first sealing ring, a second sealing ring is fixedly connected to the interior of the first sealing ring, an inner collecting tank is slidably connected to the inner wall of an outer protective tank, and a first feeding opening is formed in the outer wall of the outer protective tank; the sampling assembly is used for sampling and collecting solutions on different layers, and the sampling assembly is connected with the outer protection tank. According to the device, the sampling assembly is arranged, in the precipitation sampling process, the sampling assembly is operated to enable a dissolving solution in the PPH storage tank to enter the inner collecting tank, dissolving solutions on the upper layer, the middle layer and the lower layer are conveniently collected into the inner collecting tank, and therefore the concentration of the dissolving solution on each layer is detected; the accuracy and representativeness of sampling and analysis results are improved, accurate feeding of precipitants in downstream procedures is guaranteed, and the recovery efficiency of lithium metal is improved.

Description

Technical Field

[0001] This invention relates to the field of lithium iron phosphate battery recycling technology, and in particular to a recycling process for waste lithium iron phosphate batteries. Background Technology

[0002] Waste lithium iron phosphate battery recycling refers to a complete process of collecting, dismantling, and pre-treating discarded lithium iron phosphate batteries, and efficiently, economically, and environmentally extracting valuable metals (lithium, iron, phosphorus), graphite, and other components from them, making them a secondary resource again.

[0003] The existing process can be roughly divided into the following steps: pretreatment and dismantling, enrichment and separation of black powder from motor materials, and extraction and recovery of valuable components. It is mainly reflected in pyrometallurgy and hydrometallurgy, and some are beginning to extend to direct regeneration technology. In the hydrometallurgical process, PPH storage tanks are needed to store the solution. As a transfer station for the solution, it can temporarily store the solution produced by the previous process and stably supply the next process, ensuring the continuity and stability of the entire process.

[0004] However, in small and medium-sized factories with low levels of automation, workers typically test the concentration of the solution in the PPH storage tank through sampling ports at the bottom or side wall. The solution in the PPH storage tank will exhibit concentration stratification due to differences in height and composition. Conventional sampling methods often only test the concentration of one layer of solution, failing to ensure the concentration throughout the entire PPH storage tank. This easily leads to situations where different heights within the PPH storage tank result in different concentrations, making the sampling and analysis results unrepresentative. Consequently, downstream processes cannot add precipitants accordingly, affecting the efficiency of lithium metal recovery. Therefore, this application provides a waste lithium iron phosphate battery recycling process to meet this need. Summary of the Invention

[0005] The technical problem this invention aims to solve is to provide a recycling process for waste lithium iron phosphate batteries. By setting up a sampling component, the dissolved solution inside the PPH storage tank is drawn into an inner collection tank. This facilitates the collection of the dissolved solution from the upper, middle, and lower layers into the inner collection tank, thereby enabling the detection of the dissolved solution concentration at each layer. This improves the accuracy and representativeness of the sampling and analysis results. This design addresses the problem that existing conventional sampling methods often only detect the dissolved solution concentration at one layer, failing to ensure the concentration throughout the entire PPH storage tank. This can lead to situations where the PPH storage tank contains dissolved solutions of varying concentrations, resulting in unrepresentative sampling and analysis results.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A recycling process for waste lithium iron phosphate batteries includes the following steps: Step 1, Pre-treatment: First, put the waste lithium iron phosphate batteries into salt water to discharge them. After the discharge is complete, disassemble, crush and sort them. Step 2, Electrode Material Separation and Enrichment: The "black powder" is placed in water using the "flotation method", air bubbles are introduced and a collector is added, so that the hydrophobic graphite adheres to the air bubbles and floats up, while the hydrophilic lithium iron phosphate sinks to the bottom, thus achieving separation. Step 3, Deep Processing and Material Recycling: Using hydrometallurgical technology, valuable metals in the "black powder" are dissolved in solution in ionic form using acid. Then, the solution is purified and separated, and different metal ions in the solution are precipitated step by step. After filtration, washing and drying, lithium metal-related products are obtained. Step 4, Product Preparation and Waste Treatment: The recycled materials are purified and subjected to particle size control and other post-processing to meet the specifications of battery manufacturers. Wastewater, waste gas and waste residue are treated in strict accordance with national emission standards. It also includes a PPH storage tank body, the PPH storage tank body including a first sealing ring, a second sealing ring fixedly connected inside the first sealing ring, an outer protective tank attached to the inner wall of the second sealing ring, an inner collection tank slidably connected to the inner wall of the outer protective tank, and a first feed inlet on the outer wall of the outer protective tank; and a sampling component, the sampling component being used to sample and collect solutions at different levels, the sampling component being connected to the outer protective tank.

[0007] Optionally, the sampling component includes an abutment pad fixedly connected to the inner wall of the top of the outer protective container, a tightening pad fixedly connected to the inner wall of the outer protective container near the abutment pad, a scraping pad fixedly connected to the middle position of the tightening pad, a connecting part fixedly connected to the bottom of the tightening pad, a protective pad fixedly connected to the bottom of the connecting part, and an uneven part provided on the inner wall of the outer protective container near the protective pad.

[0008] Optionally, a limiting arc is fixedly connected to the inner wall at the middle position of the outer protective tank, an absorbent pad is snapped into the inner wall of the outer protective tank near the limiting arc, and a stop block is fixedly connected to the bottom of the limiting arc.

[0009] Optionally, a limiting frame is fixedly connected to the inner wall of the outer protective tank near the side of the limiting arc, a connecting pipe is provided in the middle of the limiting frame, a stress-bearing liner is fixedly connected to the inner wall of the limiting frame, and blocking blocks are fixedly connected to both sides of the limiting frame.

[0010] Optionally, a support platform is fixedly connected to the inner wall of the bottom of the outer protective tank, a bending plate is fixedly connected to the bottom of the support platform, and a limit ring is fixedly connected to the inner wall of the outer protective tank near the bottom of the bending plate.

[0011] Optionally, a second inlet is provided on the outer wall of the inner collection tank. ，An adapter block is fixedly connected to the outer wall of the inner collection tank. An arc-shaped groove is provided on the top of the adapter block, and a squeezing block is fixedly connected to the bottom of the adapter block.

[0012] Optionally, the outer wall of the tightening pad has a plurality of split grooves arranged in a circumferential array, the scraping pad is made of rubber, the surface of the protective pad has a plurality of slots arranged in a circumferential array, and the side of the bottom of the limiting arc is inclined.

[0013] Optionally, a protrusion is provided at the middle position of the bottom of the limiting arc, a snap-fit ​​groove is provided on the side of the absorbent pad near the outer protective tank, a number of drainage grooves are provided on the top of the absorbent pad, and the length of the blocking block is half of the limiting arc.

[0014] Optionally, the connecting pipe is made of rubber, the stress-bearing liner has a circular groove in the middle, the size of the circular groove is the same as the size of the inner wall of the connecting pipe, the outer wall of the support platform has several lightweight grooves, the bending plate is made of elastic material, and the bottom of the bending plate abuts against the top of the limiting ring.

[0015] Optionally, the size of the second feed inlet is the same as the size of the first feed inlet.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects: In the above scheme, by setting up a sampling component, the solution inside the PPH storage tank is operated to enter the inner collection tank. Since the sampling component is completely in contact with the inside of the PPH storage tank from top to bottom, it is convenient to collect the solution from the upper, middle and lower layers in the inner collection tank, thereby detecting the concentration of the solution at each layer, improving the accuracy and representativeness of sampling and analysis results, ensuring the accurate dosing of precipitant in downstream processes, and improving the recovery efficiency of lithium metal.

[0017] By incorporating a tightening pad, a scraping pad, and a protective pad into the sampling assembly, the outer wall of the outer protective tank will fit tightly against the middle position of the tightening pad and the protective pad during the sampling process. Furthermore, the middle position of the tightening pad and the protective pad is made of rubber, which can better fit the outer wall of the outer protective tank, thereby reducing the leakage of toxic gases from the main body of the PPH storage tank and improving the safety of personnel during the sampling process.

[0018] By setting up adapter blocks and compression blocks, not only can the inner collection tank be easily rotated inside the outer protective tank, improving the overall practicality of the device, but the outer protective tank and the inner collection tank can also be sealed during rotation, preventing the liquid inside the PPH storage tank from entering and preventing the liquid inside the inner collection tank from flowing out. This improves the sealing performance of the device, avoids excessive liquid between the outer protective tank and the inner collection tank, reduces the workload of the staff in cleaning, and improves the stability of the operation process. Attached Figure Description

[0019] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate embodiments of the invention and, together with the specification, further serve to explain the principles of the invention and enable those skilled in the art to practice and use the invention.

[0020] Figure 1 A first-person perspective three-dimensional structural diagram of a waste lithium iron phosphate battery recycling and processing device; Figure 2 A second-view three-dimensional structural diagram of a waste lithium iron phosphate battery recycling and processing device; Figure 3 A first-view cross-sectional three-dimensional structural diagram of a waste lithium iron phosphate battery recycling and processing device; Figure 4 A two-dimensional cross-sectional view of a waste lithium iron phosphate battery recycling and processing device. Figure 5 A schematic diagram of the three-dimensional structure of the outer protective tank, the contact pad, and the tightening pad; Figure 6 A three-dimensional enlarged structural diagram of the connecting part, protective pad, and concave-convex part; Figure 7 A three-dimensional enlarged structural diagram of the outer protective tank, inner collection tank, and contact pad; Figure 8 A three-dimensional enlarged structural diagram of the outer protective tank, the limiting arc, and the absorption pad; Figure 9 for Figure 8 A magnified three-dimensional structural diagram at point A in the middle; Figure 10 A three-dimensional enlarged schematic diagram of the limiting frame and the stress-bearing inner lining; Figure 11 for Figure 10 A magnified three-dimensional structural diagram at point B in the middle; Figure 12 A three-dimensional enlarged structural diagram of the support platform, bending plate, and limiting ring; Figure 13 A three-dimensional enlarged structural diagram of the internal collection tank, the second inlet, and the adapter block; Figure 14 for Figure 13 A magnified three-dimensional structural diagram at point C.

[0021] Figure label: 1. PPH storage tank body; 2. First sealing ring; 3. Second sealing ring; 4. Outer protective tank; 5. Inner collection tank; 6. Contact pad; 7. Tightening pad; 8. Scraping pad; 9. Connecting part; 10. Protective pad; 11. Concave and convex parts; 12. Limiting arc; 13. Absorbing pad; 14. Blocking block; 15. Limiting frame; 16. Connecting pipe; 17. Stress-bearing lining; 18. Blocking block; 19. Support platform; 20. Bending plate; 21. Limiting ring; 22. Second feed inlet; 23. Adaptor block; 24. Arc groove; 25. Extrusion block; 26. First feed inlet.

[0022] As shown in the figure, specific structures and devices are marked in the figure to clearly illustrate the structure of the embodiments of the present invention. However, this is only for illustrative purposes and is not intended to limit the present invention to this specific structure, device and environment. Those skilled in the art can adjust or modify these devices and environments according to specific needs. Detailed Implementation

[0023] The following describes in detail a waste lithium iron phosphate battery recycling process provided by the present invention with reference to the accompanying drawings and specific embodiments. It should be noted that, to make the embodiments more detailed, the following embodiments are the best and preferred embodiments; those skilled in the art can also use other alternative methods to implement some known technologies; and the accompanying drawings are only for more specific description of the embodiments and are not intended to specifically limit the present invention.

[0024] It should be noted that the use of terms such as "an embodiment," "an embodiment," "an exemplary embodiment," and "some embodiments" in the specification indicates that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments (whether explicitly described or not) should be within the knowledge of those skilled in the art.

[0025] Generally, terms can be understood at least partly from their use in context. For example, depending at least partly on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in a singular sense, or a combination of features, structures, or characteristics in a plural sense. Additionally, the term "based on" can be understood not necessarily to convey an exclusive set of factors, but rather, alternatively, depending at least partly on the context, to allow for the presence of other factors that are not necessarily explicitly described.

[0026] It is understood that the meanings of “on”, “above”, and “above” in this invention should be interpreted in the broadest manner, such that “on” means not only “directly on” something, but also includes the meaning of being “on” something with an intervening feature or layer, and that “above” or “above” means not only “on” something, but also includes the meaning of being “on” something without an intervening feature or layer.

[0027] Furthermore, spatially related terms such as “below,” “under,” “lower,” “above,” and “upper” are used herein for convenience to describe the relationship of one element or feature to one or more other elements or features, as illustrated in the accompanying drawings. Spatially related terms are intended to cover different orientations in the use or operation of the device other than those depicted in the accompanying drawings. The device may be oriented in other ways, and the spatially related descriptive terms used herein can be interpreted similarly.

[0028] like Figures 1 to 4 As shown, an embodiment of the present invention provides a recycling process for waste lithium iron phosphate batteries, including the following steps: Step 1, Pre-treatment: First, put the waste lithium iron phosphate batteries into salt water to discharge them. After the discharge is complete, disassemble, crush and sort them. Step 2, Electrode Material Separation and Enrichment: The "black powder" is placed in water using the "flotation method", air bubbles are introduced and a collector is added, so that the hydrophobic graphite adheres to the air bubbles and floats up, while the hydrophilic lithium iron phosphate sinks to the bottom, thus achieving separation. Step 3, Deep Processing and Material Recycling: Using hydrometallurgical technology, valuable metals in the "black powder" are dissolved in solution in ionic form using acid. Then, the solution is purified and separated, and different metal ions in the solution are precipitated step by step. After filtration, washing and drying, lithium metal-related products are obtained. Step 4, Product Preparation and Waste Treatment: The recycled materials are purified and subjected to particle size control and other post-processing to meet the specifications of battery manufacturers. Wastewater, waste gas and waste residue are treated in strict accordance with national emission standards. The system also includes a PPH tank body 1, with a first sealing ring 2 fixedly connected to the outer wall of the top of the PPH tank body 1. A second sealing ring 3 is fixedly connected inside the first sealing ring 2. An outer protective tank 4 is attached to the inner wall of the second sealing ring 3. An inner collection tank 5 is slidably connected to the inner wall of the outer protective tank 4. A first inlet 26 is provided on the outer wall of the outer protective tank 4. A sampling component is also included, used for sampling and collecting solutions at different levels. The sampling component is connected to the outer protective tank 4. Both the first sealing ring 2 and the second sealing ring 3 are fixed at the openings at the top of the PPH tank body 1. In practical scenarios, one or two openings at the top of the PPH tank body 1 can be selected, but it is necessary to ensure that the openings at the top of the PPH tank body 1 are in contact with the first sealing ring 2 and the second sealing ring 3. For the sealing between the sealing rings 3, the length of the outer protective tank 4 needs to be greater than the cross-sectional height of the PPH tank body 1. The outer protective tank 4 can be long, but the PPH tank body 1 cannot be short, to avoid personnel needing to come into close contact with the opening at the top of the PPH tank body 1, which could cause safety hazards. During use, the first sealing ring 2 and the second sealing ring 3 do not need to be sampled together with the outer protective tank 4, but are fixed at the top of the PPH tank body 1 to avoid repeated disassembly that could reduce the sealing performance. After the outer protective tank 4 is placed on the PPH tank body 1, the inner wall of the second sealing ring 3 is completely attached to the outer wall of the outer protective tank 4, ensuring first-level sealing during the sampling process and preventing the leakage of toxic gases from inside the PPH tank body 1.

[0029] By setting up a sampling component, the inner and outer collection tanks are placed inside the PPH storage tank during the precipitation sampling process. The sampling component is operated to allow the solution inside the PPH storage tank to enter the inner collection tank. Since the sampling component is completely in contact with the inside of the PPH storage tank from top to bottom, it is convenient to collect the solution from the upper, middle and lower layers into the inner collection tank. This allows for the detection of the solution concentration at each layer, improving the accuracy and representativeness of the sampling and analysis results, ensuring the accurate dosing of precipitant in downstream processes, and improving the recovery efficiency of lithium metal.

[0030] As one implementation method in this embodiment, such as Figures 5 to 11As shown, the sampling assembly includes an abutment pad 6 fixedly connected to the inner wall of the top of the outer protective container 4. A tightening pad 7 is fixedly connected to the inner wall of the outer protective container 4 near the abutment pad 6. A scraping pad 8 is fixedly connected to the middle position of the tightening pad 7. A connecting part 9 is fixedly connected to the bottom of the tightening pad 7. A protective pad 10 is fixedly connected to the bottom of the connecting part 9. A concave-convex part 11 is provided on the inner wall of the outer protective container 4 near the protective pad 10. A limiting arc 12 is fixedly connected to the inner wall at the middle position of the outer protective container 4. An absorbent pad 13 is snapped onto the inner wall near the limiting arc 12. A stop block 14 is fixedly connected to the bottom of the limiting arc 12. A limiting frame 15 is fixedly connected to the inner wall of the outer protective tank 4 near the side of the limiting arc 12. A connecting pipe 16 is provided in the middle of the limiting frame 15. A stress-bearing liner 17 is fixedly connected to the inner wall of the limiting frame 15. Blocking blocks 18 are fixedly connected to both sides of the limiting frame 15. Several splitting grooves are distributed in a circular array on the outer wall of the tightening pad 7. The scraping pad 8 is made of rubber. The surface of the protective pad 10... The outer protective tank 12 has several slots distributed in a circumferential array. The bottom side of the limiting arc 12 is inclined, and a protrusion is provided in the middle of the bottom of the limiting arc 12. The absorbent pad 13 has a snap-fit ​​groove on the side near the outer protective tank 4. The top of the absorbent pad 13 has several drainage grooves. The length of the abutment block 14 is half that of the limiting arc 12. The connecting pipe 16 is made of rubber. The stress-bearing liner 17 has a circular groove in the middle, and the size of the circular groove is the same as the size of the inner wall of the connecting pipe 16. It should be noted that all components inside the protective tank 4 must be coated with a liner, using fluoroplastic or PTFE material, to prevent the acid in the solution inside the PPH storage tank body 1 from corroding the sampling components. When the outer protective tank 4 and the inner collection tank 5 are placed into the interior of the PPH storage tank body 1, they will first come into contact with the abutment pad 6. The bottom of the outer protective tank 4 is designed to be conical, but the bottom is not pointed but flat. This design facilitates the initial entry of the outer protective tank 4 and the inner collection tank 5 from inside the second sealing ring 3, and from... Figure 6It can be seen that the size of the middle position of the tightening pad 7 is significantly smaller than the size of the bottom of the outer protective can 4. As the outer protective can 4 and inner collecting can 5 continue to descend, the outer wall of the outer protective can 4 begins to press against the inner wall of the contact pad 6 until they are completely fitted. The bottom of the outer protective can 4 begins to pass through the middle of the tightening pad 7, and the outer wall of the outer protective can 4 begins to contact the scraping pad 8 from bottom to top. Since the tightening pad 7 is mostly made of rubber, except for the steel ring near the outer protective can 4, the outer protective can 4 expands the size of the scraping pad 8 as it descends, eventually making the size of the middle position of the tightening pad 7 consistent with the size of the outer wall of the outer protective can 4, and the scraping pad 8 completely fitted against the outer wall of the outer protective can 4. At this point, the scraping pad 8 and the outer protective can... The space between 4 is a secondary seal. The outer protective tank 4 continues downwards, contacting the middle of the protective pad 10. Similarly, the design principle of the protective pad 10 is the same as that of the tightening pad 7, and the operation process is the same, so it will not be elaborated further. With the combined action of the tightening pad 7 and the protective pad 10, the outer protective tank 4 is ensured to be sealed around itself as it penetrates the PPH tank body 1, preventing gas leakage from the PPH tank body 1 and causing safety hazards. Once the bottom of the outer protective tank 4 has completely passed through the connecting part 9 and the protective pad 10 and entered the limiting arc 12, the engagement between the protruding part and the concave-convex part 11 on the outer wall of the outer protective tank 4 needs to be checked. In actual operation, it is impossible to guarantee the outer protective tank's proper functioning. Since the length of tank 4 matches the internal dimensions of each PPH, the position of the outer protective tank 4 can be fixed in two ways: one is to lower the bottom of the outer protective tank 4 directly to the bottom of its inner wall; the other is to use interlocking between the protrusions and recesses 11 on the outer wall of the outer protective tank 4. Both methods are acceptable. Next, we will describe the interior of the outer protective tank 4. The inner wall of the outer protective tank 4 is fixed with limiting arcs 12 and absorption pads 13. During the lowering process of the outer protective tank 4, the limiting arcs 12, absorption pads 13, and abutment blocks 14 will not be touched. The limiting arcs 12 are placed synchronously, arranged in a circular array on the inner wall of the outer protective tank 4, and linearly arranged in a three-layer pattern (top, middle, and bottom). On the inner wall, both circular and linear arrays are formed, while the absorption pad 13 is a closed ring. The overall material is still rubber. As mentioned above, the components located on the inner wall of the outer protective tank 4 are coated with a coating that resists acidic solutions. Therefore, they are consumables that need to be replaced during use. Thus, the absorption pad 13 has a snap-fit ​​groove on its side for easy replacement and fixation after replacement. The stop block 14 is symmetrical about the center of the outer protective tank 4, and there are only two stop blocks 14. They are not synchronized with the distribution of the limiting arc 12. A trough is designed on the top of the absorption pad 13 to collect and absorb the dripping solution, so as to reduce the mixing of solutions from different layers when the sample is poured, thereby improving the accuracy of the test.

[0031] During the process of lowering the outer protective tank 4 into the PPH storage tank body 1, the inner collecting tank 5 needs to be lowered simultaneously. The outer protective tank 4 and the inner collecting tank 5 are in a closed state. During the continuous lowering process, the dissolved liquid inside the PPH storage tank body 1 cannot enter the inner collecting tank 5. On the one hand, the connecting pipe 16 is squeezed and deformed, and cannot transport liquid normally. On the other hand, the inner collecting tank 5, being inside the outer protective tank 4, will squeeze the stress-bearing liner 17 towards the first feed inlet 26, thereby blocking the hole of the first feed inlet 26. This prevents the dissolved liquid inside the PPH storage tank body 1 from entering the outer protective tank 4 through the first feed inlet 26. In order to facilitate the blocking of the first feed inlet 26 by the stress-bearing liner 17, the middle position of the stress-bearing liner 17 is hollowed out to improve the deformation capacity of the stress-bearing liner 17.

[0032] By incorporating a tightening pad 7, a scraping pad 8, and a protective pad 10 into the sampling assembly, the outer wall of the outer protective tank 4 will fit tightly against the middle position of the tightening pad 7 and the protective pad 10 during the sampling process. Furthermore, the middle position of the tightening pad 7 and the protective pad 10 is made of rubber, which can better fit the outer wall of the outer protective tank 4, thereby reducing the leakage of toxic gases from the PPH storage tank body 1 and improving the safety of personnel during the sampling process.

[0033] As one implementation method in this embodiment, such as Figure 12 and Figure 13As shown, a support platform 19 is fixedly connected to the inner wall of the bottom of the outer protective tank 4, and a bending plate 20 is fixedly connected to the bottom of the support platform 19. A limiting ring 21 is fixedly connected to the inner wall of the outer protective tank 4 near the bottom of the bending plate 20. A second feed inlet 22 is opened on the outer wall of the inner collection tank 5. Several lightweight grooves are provided on the outer wall of the support platform 19. The bending plate 20 is made of elastic material. The bottom of the bending plate 20 abuts against the top of the limiting ring 21. The size of the second feed inlet 22 is the same as the size of the first feed inlet 26. The outer wall of the support platform 19 is attached to the inner wall of the outer protective tank 4, and the bottom of the bending plate 20 abuts against the bottom of the inner wall of the outer protective tank 4. The position of the bending plate 20 moves synchronously with the position of the support platform 19. The bottom of the bending plate 20 abuts against the top of the limiting ring 21. As the top of the support platform 19 contacts and squeezes the bottom of the inner collection tank 5, the bending plate 20 deforms, thereby... The inner collection tank 5 moves downward inside the outer protective tank 4, aligning the second inlet 22 on the inner collection tank 5 with the first inlet 26 on the outer protective tank 4. After alignment, the connecting pipe 16 is no longer squeezed by the outer wall of the inner collection tank 5 and begins to reset. Since the second inlet 22 and the first inlet 26 are aligned at this time, it will enter the second inlet 22 during the reset process. At this time, the position of the outer protective tank 4 is stable, the second inlet 22 and the first inlet 26 are also aligned, and the connecting pipe 16 also enters the second inlet 22. The solution inside the PPH storage tank body 1 will enter the first inlet 26 and then enter the second inlet 22 through the connecting pipe 16. The inner collection tank 5 is divided into three chambers, which correspond to the upper, middle and lower layers respectively, so that the solution inside the PPH storage tank body 1 can be collected in layers.

[0034] As one implementation method in this embodiment, such as Figure 13 and Figure 14As shown, an adapter block 23 is fixedly connected to the outer wall of the inner collection tank 5. An arc-shaped groove 24 is formed at the top of the adapter block 23, and a pressing block 25 is fixedly connected to the bottom of the adapter block 23. The size of the adapter block 23 is smaller than the size of the limiting arc 12. The size of the arc-shaped groove 24 is the same as the size of the protrusion. The outer wall of the pressing block 25 is respectively attached to the outer walls of the connecting pipe 16 and the limiting frame 15. In the initial state, that is, when the outer protective tank 4 and the inner collection tank 5 enter the interior of the PPH storage tank body 1 together, the adapter block 23 and the pressing block 25 are positioned between the two limiting arcs 12 and above them. The bending plate 20 is used to... The supporting force lifts the inner collection tank 5. At this time, neither the adapter block 23 nor the squeezing block 25 contacts the limiting arc 12 and the connecting pipe 16, and the inner collection tank 5 is in a stable state. The connecting pipe 16 is squeezed by the outer wall of the inner collection tank 5 and undergoes irregular deformation, preventing the solution inside the PPH storage tank body 1 from entering. A small amount of solution that enters will fall into the groove on top of the absorbent pad 13. Sampling begins once the outer protective tank 4 has entered and stabilized inside the PPH storage tank body 1, without prolonged lingering to avoid excessive solution seeping into the sampling device. During sampling, the operator is positioned on top of the PPH storage tank body 1, holding the inner collection tank... The top of tank 5 is pressed downwards. At this time, the bottom of the inner collection tank 5 will abut against the top of the support platform 19, and the support platform 19 will move downwards under the pressure. The bending plate 20 will deform and bend during the downward movement of the support platform 19. At the same time, the adapter block 23 and the extrusion block 25 on the outer wall of the inner collection tank 5 will also move downwards with the inner collection tank 5. Since the deformation of the bending plate 20 has an upper limit, when it can no longer be pressed and moved downwards, it means that the deformation value of the bending plate 20 is the maximum, and the downward movement height of the support platform 19 is also the maximum. At this time, it will be found that the second feed port 22, which was originally located at the top, begins to move downwards and eventually comes into contact with the first feed port. When the ports 26 are aligned and on the same plane, the connecting pipe 16 is no longer squeezed by the outer wall of the inner collection tank 5 and resets. During the reset process, it will move towards the inside of the second feed port 22. Then, the solution inside the PPH storage tank body 1 will enter the inner cavity of the inner collection tank 5 through the first feed port 26, the connecting pipe 16 and the second feed port 22. After a period of time (the sampling time can be arbitrary. The inner cavity of the inner collection tank 5 can be filled with solution or partially filled with solution. The purpose of the sampling device is to take the solution of this layer for testing the concentration value of this layer, which is unrelated to the volume of solution), this process requires the operator to continuously press the top of the inner collection tank 5.

[0035] After sampling, the solution in the inner cavity of the inner collection tank 5 needs to be sealed. At this time, rotate the top of the inner collection tank 5 clockwise, and the entire inner collection tank 5 will rotate clockwise as well. Since the top of the adapter block 23 is lower than the bottom of the limiting arc 12, there is no need to press it down; simply rotate it. During the elastic reset of the bending plate 20, the top of the adapter block 23 will abut against the bottom of the limiting arc 12, and the arc-shaped groove 24 will also engage with the protrusion at the bottom of the limiting arc 12. Continue rotating as follows... Figure 9 As shown, the stop block 14 is located below the left limiting arc 12, but not below the right limiting arc 12. Similarly, since the stop block 14 is centrally symmetrical, from the opposite angle, the stop block 14 is located below the right limiting arc 12, but not below the left limiting arc 12. Thus, during the rotation of the inner collecting tank 5, the second inlet 22 also rotates and is sealed by the absorption pad 13, preventing the dissolved liquid inside the second inlet 22 from flowing out. The extrusion block 25 gradually approaches the position of the connecting pipe 16. During the rotation, the connecting pipe 16 will slide out from the hole of the second inlet 22 and be squeezed and deformed again by the outer wall of the inner collecting tank 5. The extrusion block 25 will replace the outer wall of the inner collecting tank 5 to squeeze the connecting pipe 16 and the stressed inner liner 17 more deeply, causing the connecting pipe 16 and the stressed inner liner 17 to move towards the first inlet 26 until the deformation of the connecting pipe 16 reaches its maximum effect and is in a complete state. In an irregular state, if the connecting pipe 16 is blocked, the first feed port 26 will also be blocked. The same method is used to seal the other two layers, and they are carried out simultaneously. At the bottom of the inner collection tank 5, there is a mutual force of the elastic reset of the bending plate 20. At the middle position of the inner collection tank 5, there is a mutual force between the top of the adapter block 23 and the bottom of the limiting arc 12. This can better ensure the squeezing force of the squeezing block 25 on the connecting pipe 16 and the stressed inner liner 17. In this way, the outer protective tank 4 is pulled out from the inside of the PPH storage tank body 1. During the pulling process, there will be residual liquid on the outer wall of the outer protective tank 4. Since the middle positions of the protective pad 10 and the tightening pad 7 are tightly attached to the outer wall of the outer protective tank 4, when it is taken out, the protective pad 10 will perform the first scraping and cleaning of the outer wall of the outer protective tank 4, and the scraping pad 8 will perform the second scraping and cleaning of the outer wall of the outer protective tank 4, minimizing the amount of liquid on the outer wall of the outer protective tank 4 and improving the safety of the staff.

[0036] After removal, place the sampling component horizontally, ensuring that the first inlet 26 is at the bottom. Use a container to collect the sample. Rotate the top of the inner collection tank 5 counterclockwise, causing the adapter block 23 and the squeezing block 25 to rotate toward the middle position of the two limiting arcs 12. If the inner collection tank 5 automatically bounces upward during the rotation, it indicates that the adapter block 23 and the squeezing block 25 have disengaged from the middle position of the two limiting arcs 12 under the elastic reset action of the bending plate 20. At this time, the second inlet 22 and the first inlet 26 are on the same horizontal plane, and the connecting pipe 16 is also inside the hole of the second inlet 22. The dissolving liquid flows out from the second inlet 22 along the connecting pipe 16 and the first inlet 26 through the inner cavity of the inner collection tank 5 and is then sent to the testing center.

[0037] By setting the adapter block 23 and the squeezing block 25, not only can the inner collection tank 5 be easily rotated inside the outer protective tank 4, improving the overall practicality of the device, but the outer protective tank 4 and the inner collection tank 5 can also be sealed during the rotation process, preventing the liquid inside the PPH storage tank body 1 from entering and preventing the liquid inside the inner collection tank 5 from flowing out, thus improving the sealing performance of the device and avoiding the presence of too much liquid between the outer protective tank 4 and the inner collection tank 5, reducing the workload of the staff in cleaning and improving the stability of the operation process.

[0038] The working principle of the technical solution provided by this invention is as follows: When the outer protective tank 4 and the inner collecting tank 5 are placed into the PPH storage tank body 1, they will first come into contact with the contact pad 6. The outer wall of the outer protective tank 4 will then press against the inner wall of the contact pad 6 until they are completely in contact. The bottom of the outer protective tank 4 will then pass through the middle of the tightening pad 7, and the outer wall of the outer protective tank 4 will begin to contact the scraping pad 8 from bottom to top. Since the tightening pad 7 is mostly made of rubber, except for the steel ring near the outer protective tank 4, the outer protective tank 4 will expand the size of the scraping pad 8 as it descends, eventually causing the middle of the tightening pad 7 to... The dimensions of the outer protective tank 4 are consistent with the outer wall dimensions, and the scraping pad 8 is completely attached to the outer wall of the outer protective tank 4. At this time, the scraping pad 8 and the outer protective tank 4 are in a secondary seal. Then the outer protective tank 4 continues downward and will contact the middle position of the protective pad 10. Similarly, the design principle of the protective pad 10 is the same as that of the tightening pad 7, and the operation process is the same as that of the tightening pad 7, so we will not go into details. Under the joint action of the tightening pad 7 and the protective pad 10, it is ensured that the outer protective tank 4 is in a sealed state when it is deeply inserted into the interior of the PPH storage tank body 1.

[0039] During sampling, the operator is positioned on top of the PPH storage tank body 1 and presses downwards from the top of the inner collection tank 5. At this time, the bottom of the inner collection tank 5 presses against the top of the support platform 19, causing the support platform 19 to move downwards under pressure. The bending plate 20 deforms and bends during this downward movement of the support platform 19. Simultaneously, the adapter block 23 and the extrusion block 25 on the outer wall of the inner collection tank 5 also shift downwards along with the inner collection tank 5. Since the deformation of the bending plate 20 has an upper limit, when it can no longer be pressed downwards, it indicates that the deformation value of the bending plate 20 is at its maximum, and the downward movement height of the support platform 19 is also at its maximum. At this point, it will be observed that the second feed inlet 22, which was originally located at the top, begins to... The tube moves downward and eventually aligns with the first inlet 26 on the same plane. At this point, the connecting pipe 16 is no longer squeezed by the outer wall of the inner collection tank 5 and resets. During the reset process, the tube moves towards the inside of the second inlet 22. Then, the solution inside the PPH storage tank body 1 enters the inner cavity of the inner collection tank 5 through the first inlet 26, the connecting pipe 16, and the second inlet 22. After a period of time (the sampling time is arbitrary; the inner cavity of the inner collection tank 5 can be filled with solution or partially filled with solution. The purpose of the sampling device is to take the solution at this level to detect the concentration value of this level, which is unrelated to the volume of the solution), this process requires the operator to continuously press the top of the inner collection tank 5.

[0040] After sampling, the solution in the inner cavity of the inner collection tank 5 needs to be sealed. At this time, rotate the top of the inner collection tank 5 clockwise, and the entire inner collection tank 5 will also rotate clockwise. The top of the adapter block 23 is also lower than the bottom of the limiting arc 12, so there is no need to press it down. Just rotate it. During the elastic reset of the bending plate 20, the top of the adapter block 23 will abut against the bottom of the limiting arc 12, and the arc groove 24 will also be engaged with the protrusion at the bottom of the limiting arc 12. Continue to rotate. During the rotation, the connecting pipe 16 will slide out from the hole of the second feed port 22 and be squeezed and deformed again by the outer wall of the inner collection tank 5. The squeezing block 25 will replace the outer wall of the inner collection tank 5 to squeeze the connecting pipe 16 and the stress-bearing liner 17. The deeper compression causes the connecting pipe 16 and the stressed inner liner 17 to move towards the first feed port 26 until the connecting pipe 16 deforms to its maximum effect. If the connecting pipe 16 is blocked, the first feed port 26 will also be blocked. The sealing methods of the other two layers are operated in the same way. During the pulling process, there will be residual liquid on the outer wall of the outer protective tank 4. Since the middle positions of the protective pad 10 and the tightening pad 7 are tightly attached to the outer wall of the outer protective tank 4, when it is taken out, the protective pad 10 will perform the first scraping and cleaning of the outer wall of the outer protective tank 4, and the scraping pad 8 will perform the second scraping and cleaning of the outer wall of the outer protective tank 4, minimizing the amount of liquid on the outer wall of the outer protective tank 4 and improving the safety of the staff.

[0041] After removal, place the sampling component horizontally, ensuring that the first inlet 26 is at the bottom. Use a container to collect the sample. Rotate the top of the inner collection tank 5 counterclockwise, causing the adapter block 23 and the squeezing block 25 to rotate toward the middle position of the two limiting arcs 12. If the inner collection tank 5 automatically bounces upward during the rotation, it indicates that the adapter block 23 and the squeezing block 25 have disengaged from the middle position of the two limiting arcs 12 under the elastic reset action of the bending plate 20. At this time, the second inlet 22 and the first inlet 26 are on the same horizontal plane, and the connecting pipe 16 is also inside the hole of the second inlet 22. The dissolving liquid flows out from the second inlet 22 along the connecting pipe 16 and the first inlet 26 through the inner cavity of the inner collection tank 5 and is then sent to the testing center.

[0042] This invention encompasses any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of this invention. To provide the public with a thorough understanding of this invention, specific details are described in detail in the following preferred embodiments; however, those skilled in the art will fully understand the invention even without these details. Furthermore, to avoid unnecessary misunderstanding of the essence of this invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0043] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A recycling process for waste lithium iron phosphate batteries, characterized in that, Includes the following steps: Step 1, Pre-treatment: First, put the waste lithium iron phosphate batteries into salt water to discharge them. After the discharge is complete, disassemble, crush and sort them. Step 2, Electrode Material Separation and Enrichment: The "black powder" is placed in water using the "flotation method", air bubbles are introduced and a collector is added, so that the hydrophobic graphite adheres to the air bubbles and floats up, while the hydrophilic lithium iron phosphate sinks to the bottom, thus achieving separation. Step 3, Deep Processing and Material Recycling: Using hydrometallurgical technology, valuable metals in the "black powder" are dissolved in solution in ionic form using acid. Then, the solution is purified and separated, and different metal ions in the solution are precipitated step by step. After filtration, washing and drying, lithium metal-related products are obtained. Step 4, Product Preparation and Waste Treatment: The recycled materials are purified and subjected to particle size control and other post-processing to meet the specifications of battery manufacturers. Wastewater, waste gas and waste residue are treated in strict accordance with national emission standards. It also includes a PPH storage tank body, the PPH storage tank body includes a first sealing ring, a second sealing ring is fixedly connected inside the first sealing ring, an outer protective tank is attached to the inner wall of the second sealing ring, an inner collecting tank is slidably connected to the inner wall of the outer protective tank, and a first feed inlet is opened on the outer wall of the outer protective tank; A sampling assembly for collecting solutions from different layers, the sampling assembly being connected to the outer protective tank.

2. The waste lithium iron phosphate battery recycling process according to claim 1, characterized in that, The sampling assembly includes an abutment pad fixedly connected to the inner wall of the top of the outer protective container. A tightening pad is fixedly connected to the inner wall of the outer protective container near the abutment pad. A scraping pad is fixedly connected to the middle position of the tightening pad. A connecting part is fixedly connected to the bottom of the tightening pad. A protective pad is fixedly connected to the bottom of the connecting part. The inner wall of the outer protective container near the protective pad has a concave-convex part.

3. The waste lithium iron phosphate battery recycling process according to claim 2, characterized in that, A limiting arc is fixedly connected to the inner wall of the outer protective tank in the middle position. An absorbent pad is snapped into the inner wall of the outer protective tank near the limiting arc. A stop block is fixedly connected to the bottom of the limiting arc.

4. The waste lithium iron phosphate battery recycling process according to claim 3, characterized in that, A limiting frame is fixedly connected to the inner wall of the outer protective tank near the side of the limiting arc. A connecting pipe is provided in the middle of the limiting frame. A stress-bearing liner is fixedly connected to the inner wall of the limiting frame. Blocks are fixedly connected to both sides of the limiting frame.

5. The waste lithium iron phosphate battery recycling process according to claim 4, characterized in that, A support platform is fixedly connected to the inner wall of the bottom of the outer protective tank, and a bending plate is fixedly connected to the bottom of the support platform. A limit ring is fixedly connected to the inner wall of the outer protective tank near the bottom of the bending plate.

6. The waste lithium iron phosphate battery recycling process according to claim 1, characterized in that, The outer wall of the inner collecting tank is provided with a second inlet. ， An adapter block is fixedly connected to the outer wall of the inner collection tank. An arc-shaped groove is provided on the top of the adapter block, and a squeezing block is fixedly connected to the bottom of the adapter block.

7. The waste lithium iron phosphate battery recycling process according to claim 3, characterized in that, The outer wall of the tightening pad has a circumferential array of several split grooves, the scraping pad is made of rubber, the surface of the protective pad has a circumferential array of several slots, and the bottom side of the limiting arc is inclined.

8. The waste lithium iron phosphate battery recycling process according to claim 7, characterized in that, The bottom of the limiting arc has a protrusion in the middle, the absorbent pad has a snap-fit ​​groove on the side near the outer protective tank, the top of the absorbent pad has several drainage grooves, and the length of the blocking block is half of the limiting arc.

9. The waste lithium iron phosphate battery recycling process according to claim 5, characterized in that, The connecting pipe is made of rubber, and a circular groove is provided in the middle of the stress-bearing liner. The size of the circular groove is the same as the size of the inner wall of the connecting pipe. The outer wall of the support platform is provided with several lightweight grooves. The bending plate is made of elastic material, and the bottom of the bending plate abuts against the top of the limiting ring.

10. The waste lithium iron phosphate battery recycling process according to claim 3, characterized in that, The size of the second feed inlet is the same as that of the first feed inlet.

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