Lithium iron phosphate wet slurry demagnetizing and filtering device

Abstract

The utility model discloses a lithium iron phosphate wet slurry demagnetizing and filtering device which comprises a barrel body, a feeding hole is formed in the upper part of the side wall of the barrel body, and a discharging hole is formed in the bottom of the barrel body; a filter basket for intercepting large-particle foreign matters is arranged in the barrel and between the feed port and the discharge port, and a magnetic rod group for removing metal foreign matters in wet slurry is arranged in the middle of an upper cover of the barrel; and the magnetic rod group comprises a plurality of magnetic rods with narrow upper parts and wide lower parts. Filtering and demagnetizing treatment are completed in one device, production equipment is simplified, the production process is simplified, and the risk that a production line is too long to increase introduction of magnetic substances is reduced. The magnetism of the magnetic bar with the narrow upper part and the wide lower part is gradually increased, and the magnetic substances in the wet powder can be controlled in a lower range by the higher magnetism in the place with lower concentration of the magnetic substances at the bottom, so that higher demagnetizing efficiency, easiness in cleaning and wear resistance are ensured; the filtered slurry is more uniform, the demagnetizing efficiency is high, and the quality of a lithium iron phosphate finished product is improved; the device is simple in structure, low in manufacturing cost and easy to popularize.

Description

TECHNICAL FIELD

[0001] The utility model relates to a wet slurry decontamination device, especially to a lithium iron phosphate wet slurry demagnetization filter device. BACKGROUND

[0002] The lithium iron phosphate positive electrode material has the advantages of excellent thermal stability, good cycle life, electrochemical stability and environmental friendliness, and becomes one of the most ideal positive electrode materials in the field of power batteries. However, when magnetic metal impurities are introduced into the lithium iron phosphate material, the life and safety of the battery will be seriously damaged. During the formation stage of the battery, the metal impurities will be oxidized at the positive electrode and then reduced at the negative electrode. When the metal elements at the negative electrode accumulate to a certain extent, dendrites will be formed, causing the perforation of the separator, the internal short circuit of the battery, the increase of the self-discharge rate of the battery, and even the fire and explosion of the battery, affecting the safety performance of the battery. Therefore, the prevention and control of magnetic substances during the production process of the lithium iron phosphate positive electrode material is particularly important. In the process of preparing lithium iron phosphate by the solid phase method, the slurry in the front wet zone needs to be demagnetized to reduce the magnetic metal impurities in the lithium iron phosphate positive electrode material. Common demagnetization equipment includes electric demagnetization, semi-automatic permanent magnet iron remover, multi-tube iron remover, pipeline iron remover, etc. The wet zone slurry needs to be sieved. First, large particles are intercepted to make the particle size distribution of the slurry narrower, so that the performance of the finished product is better. Second, the wear of the conveying pump, sand mill and atomizer caused by large particles is reduced, prolonging the service life of the equipment. Third, the introduction of metal impurities caused by equipment wear is reduced. Common filtering equipment includes slurry screen and bag filter. SUMMARY

[0003] The utility model aims at simplifying the production line equipment of the weilai and improving the demagnetization efficiency, and provides a kind of.

[0004] Technical scheme: the lithium iron phosphate wet slurry demagnetization filter device disclosed by the utility model comprises a cylinder, a feeding port is arranged on the upper part of the side wall of the cylinder, and a discharging port is arranged at the bottom; a filter basket for intercepting large particle impurities is arranged between the inside of the cylinder, the feeding port and the discharging port; a magnetic rod group for removing metal impurities in the wet slurry is arranged in the middle of the upper cover of the cylinder; and the magnetic rod group comprises a plurality of magnetic rods that are narrow at the top and wide at the bottom.

[0005] Further, the filtering and demagnetization processes are completed in one device, which simplifies the production equipment and the generation process and reduces the risk of introducing magnetic substances due to the overlong production line. The magnetic rods are narrow at the top and wide at the bottom, and the magnetism gradually increases. The magnetic substances are gradually removed during the downward process of the wet powder. The higher magnetism at the place where the concentration of magnetic substances is lower at the bottom can more thoroughly remove the magnetic substances in the wet powder, ensuring a higher demagnetization efficiency.

[0006] Further, the magnetic rod is preferably a neodymium iron boron super strong permanent magnet material, and the magnetic rod has a gauss value of 8000-12000 GS.

[0007] Further, a plurality of annular cleaning brush boxes for scraping off magnetic foreign matters on the magnetic rod are threadedly connected to the upper cover, the magnetic rod is arranged in the cylinder through the annular cleaning brush box, the inner diameter of the annular cleaning brush box is equal to the maximum diameter of the magnetic rod, a plastic push piece is arranged in the annular cleaning brush box, and the length of the plastic push piece is greater than the diameter difference of the magnetic rod. When the magnetic rod penetrates through the brush box, the plastic push piece scrapes off the magnetic substances adsorbed on the magnetic rod to clean the magnetic rod. The plastic push piece is replaced when the abrasion is greater than 30%.

[0008] Further, the filter basket is preferably made of stainless steel and has a mesh number of 3-30 meshes, so that large-particle foreign matters are filtered out and magnetic substances are further prevented from being introduced.

[0009] Further, a filter basket supporting ring is arranged on the inner wall of the cylinder, a filter basket lifting ring is arranged on the top of the filter basket, the filter basket lifting ring is hung on the filter basket supporting ring to fix the filter basket, and a rubber ring for preventing abrasion is arranged between the filter basket lifting ring and the filter basket supporting ring, so that the filter basket is prevented from being abraded to introduce magnetic substances during use.

[0010] Further, the utility model also provides a magnetic rod cleaning tool which is used in cooperation with the lithium iron phosphate wet slurry demagnetization and filtration device, the magnetic rod cleaning tool comprises a top plate for erecting a magnetic rod group, a second movable rod for fixing the magnetic rod group is arranged on the top plate, a slag receiving disc for receiving and cleaning dirt is arranged below the top plate, and four supporting columns are arranged around the top plate. When the filter basket or the magnetic rod group needs to be cleaned and replaced, the upper cover is taken down from the magnetic rod group and is erected on the top plate of the cleaning tool, the magnetic rod is taken out or is inserted into the annular cleaning brush box to scrape off the magnetic substances on the top, and the slag receiving disc collects and cleans the dirt.

[0011] Further, the magnetic rod group is fixed through the first movable rod and the upper cover, and the upper cover is sealingly connected with the cylinder through a flange.

[0012] Further, the cylinder is made of stainless steel, and a drain port and a support are arranged at the bottom of the cylinder.

[0013] Compared with the prior art, the utility model has the following advantages: 1. The production line is simplified, the filtration and demagnetization are completed in the same device, and the risk of introducing magnetic substances is reduced due to the long production line; 2. The magnetic rod is narrow at the top and wide at the bottom, the magnetism gradually increases, the higher magnetism at the bottom where the concentration of magnetic substances is lower can control the magnetic substances in the wet powder material in a lower range, and the demagnetization efficiency is ensured to be high; 3. The magnetic rod is easy to clean and resistant to abrasion; 4. The slurry after filtration is more uniform, the demagnetization efficiency is high, and the quality of the lithium iron phosphate product is improved; and 5. The device has a simple structure, low manufacturing cost and is easy to popularize. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model;

[0015] Figure 2 This is a schematic diagram of the internal structure of the present invention;

[0016] Figure 3 This is an assembly diagram of the top cover and magnetic rod assembly of this utility model;

[0017] Figure 4 This is a schematic diagram of the structure of the filter basket of this utility model;

[0018] Figure 5 This is a schematic diagram of the structure of the annular cleaning brush box of this utility model;

[0019] Figure 6 This is a schematic diagram of the structure of the magnetic rod cleaning fixture of this utility model. Detailed Implementation

[0020] The technical solution of this utility model will be further described below with reference to the accompanying drawings.

[0021] like Figures 1-4 The illustrated demagnetizing and filtering device for lithium iron phosphate wet slurry includes a stainless steel cylinder 9. The upper part of the cylinder 9's side wall has an inlet 1, and the bottom has an outlet 2. The bottom of the cylinder 9 also has a drain outlet 3 and a support 10. Inside the cylinder 9, between the inlet 1 and the outlet 2, is a filter basket 11 for intercepting large particles. The filter basket 11 is made of stainless steel with a mesh size of 3-30. A filter basket support ring 113 is provided on the inner wall of the cylinder 9. A filter basket hanging ring 111 is provided on the top of the filter basket 11, and the filter basket 111 is hung on the filter basket support ring 113 to fix the filter basket 11. A wear-preventing rubber ring 112 is provided between the filter basket hanging ring 111 and the filter basket support ring 113. Figure 5 As shown, the cylinder 9 and the upper cover 4 are sealed together by a flange 8. Two lifting rings 7 are symmetrically arranged on the upper cover 4. Four annular cleaning brush boxes 41 are threaded into the center of the upper cover 4. Four magnetic rods 52 of the magnetic rod assembly 5, used to remove metallic foreign objects from wet slurry, pass through the annular cleaning brush boxes 41 and are placed inside the cylinder 9. They are fixed to the upper cover 4 by a first movable rod 6. The magnetic rods 52 are cylindrical, narrow at the top and wide at the bottom, preferably made of neodymium iron boron ultra-strong permanent magnet material, with a Gauss value of 8000–12000 GS. The inner diameter of the annular cleaning brush box 41 is equal to the maximum diameter of the magnetic rod 52. The annular cleaning brush box 41 contains a circular plastic paddle, the length of which is greater than the radius difference of the magnetic rod 52. Figure 6As shown, the magnetic rod cleaning tool 12 includes a top plate 123 for erecting the magnetic rod set 5, the top plate 123 is provided with a second movable rod 121 for fixing the magnetic rod set 5, and a slag receiving plate 122 is arranged below the top plate 123 for receiving the cleaning dirt, and four support columns 124 are arranged around the top plate 123.

[0022] In use, the lithium iron phosphate wet slurry enters from the feed port 1, the magnetic material is adsorbed on the magnetic rod 52, and the large-particle impurities are intercepted in the filter basket 11, and the filtered slurry after magnetic removal enters the next process from the discharge port 2. After working for a period of time, the magnetic rod 52 adsorbs a large amount of magnetic material, which reduces the magnetic force or the deposition of impurities in the filter basket 11, which reduces the flow rate of the wet slurry. It can be removed for cleaning or replacement. Close the feed port 1 and the discharge port 2 to stop the equipment from feeding and discharging, open the blowdown port 3 to discharge the slurry in the equipment, unscrew the flange 8, lift the lifting ring 7, and take out the magnetic rod set 5 together with the upper cover 4 and place it on the magnetic rod cleaning tool 12, push the second movable rod 121 to fix the magnetic rod set 5 and the upper cover 4, open the first movable rod 6 to take out the magnetic rod set 5, and the magnetic rod 52 passes through the annular cleaning brush box 41 during the removal process. The magnetic impurity particles are brushed off by the plastic paddles inside the brush box, and the magnetic impurity particles fall into the tool slag receiving plate 122. A small amount of pure water is used to rinse the annular cleaning brush box 41 to prevent magnetic impurity particles from remaining on the plastic paddles inside the brush box. The cleaning water falls into the tool slag receiving plate 122. The magnetic rod set 5 is inserted into the annular cleaning brush box 41 again and removed again to clean the magnetic rod 52 again. And regularly use the Gauss meter to detect the surface of the magnetic rod, if the magnetic rod is lower than 8000GS, it is recommended to replace the magnetic rod, and when the wear degree of the plastic paddles inside the brush box is > 30%, replace the annular cleaning brush box 41. Lift the filter basket lifting ring 111 to remove the filter basket 11 for flushing or replacement.

Claims

1. A lithium iron phosphate wet slurry demagnetization filter device, comprising a cylinder (9), the upper part of the side wall of the cylinder (9) is provided with a feeding port (1), and the bottom is provided with a discharging port (2); characterized in that, The inside of the barrel (9), the feeding port (1) and the discharging port (2) are provided with a filter basket (11) for intercepting large-particle foreign matters, and the middle of the upper cover (4) of the barrel (9) is provided with a magnetic rod group (5) for removing metal foreign matters in wet slurry.

2. The lithium iron phosphate wet slurry demagnetization filter device according to claim 1, characterized in that, The magnetic rod (52) is made of neodymium-iron-boron super-strong permanent magnetic material, and the gauss value of the magnetic rod is 8000-12000 GS.

3. The lithium iron phosphate wet slurry demagnetization filter device according to claim 1, characterized in that, A plurality of annular cleaning brush boxes (41) for scraping off magnetic foreign matters on the magnetic rod (52) are threadedly connected to the upper cover (4), and the magnetic rod (52) penetrates through the annular cleaning brush box (41) and is arranged in the barrel (9).

4. The lithium iron phosphate wet slurry demagnetization filter device according to claim 3, characterized in that, The inner diameter of the annular cleaning brush box (41) is equal to the maximum diameter of the magnetic rod (52), and a plastic paddle is arranged in the annular cleaning brush box (41), and the length of the plastic paddle is greater than the diameter difference of the magnetic rod (52).

5. The lithium iron phosphate wet slurry demagnetization filtration device according to claim 1, characterized in that, The filter basket (11) is made of stainless steel material, and the mesh number is 3-30.

6. The lithium iron phosphate wet slurry demagnetization filtration device according to claim 1, characterized in that, The inner wall of the barrel (9) is provided with a filter basket supporting ring (113), and the top of the filter basket (11) is provided with a filter basket lifting ring (111), the filter basket lifting ring (111) is hung on the filter basket supporting ring (113) to fix the filter basket (11), and a rubber ring (112) is arranged between the filter basket lifting ring (111) and the filter basket supporting ring (113) to prevent abrasion.

7. The lithium iron phosphate wet slurry demagnetization filtration device according to claim 1, characterized in that, The magnetic rod cleaning tool (12) comprises a top plate (123) for erecting the magnetic rod group (5), a second movable rod (121) for fixing the magnetic rod group (5) is arranged on the top plate (123), a slag receiving disc (122) for receiving and cleaning dirt is arranged below the top plate (123), and four supporting columns (124) are arranged around the top plate (123).

8. The lithium iron phosphate wet slurry demagnetization filtration device according to claim 1, characterized in that, The magnetic rod group (5) is fixed through the first movable rod (6) and the upper cover (4), and the upper cover (4) is sealingly connected with the barrel (9) through the flange (8).

9. The lithium iron phosphate wet slurry demagnetization filtration device according to claim 1, characterized in that, The barrel (9) is made of stainless steel material, and the bottom is provided with a blowdown port (3) and a support (10).

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