Semiconductor polishing slurry recycling device

Abstract

This invention belongs to the field of polishing slurry recycling and treatment technology, and discloses a semiconductor polishing and grinding slurry circulation treatment device, including a chemical precipitation tank. The top of the chemical precipitation tank is equipped with a flocculant inlet, a water inlet, and a motor. Inside the chemical precipitation tank, a rotating shaft and a stirrer are directly driven by the motor. Multiple sets of sealing grooves are formed on the inner wall of the chemical precipitation tank. The inner wall of each sealing groove has an installation groove. A spring and a sealing plate are sealed and engaged inside the installation groove, and the sealing plate is securely engaged within the sealing groove. This device utilizes the stirrer to generate a large rotational thrust on the water, producing centrifugal force to break up the sediment and force it all through a filter tank. The unidirectional thrust generated by the water flow quickly concentrates the sediment on the filter screen surface, thereby greatly accelerating the collection speed of flocculated sediment and improving the working efficiency of the device.

Description

Technical Field

[0001] This invention belongs to the field of polishing slurry recycling and treatment technology, specifically a semiconductor polishing and grinding slurry recycling and treatment device. Background Technology

[0002] The recycling of semiconductor polishing slurry is a complex and critical process. The wastewater generated during the operation of the slurry mainly comes from the cutting and grinding processes. The chemicals, cooling water, and washing water used in these processes will produce wastewater containing pollutants such as heavy metals, organic matter, unstable pH levels, and high concentrations of silicon compounds. In order to prevent the direct discharge of this wastewater and damage to the environment, the semiconductor industry has developed a variety of treatment technologies to achieve environmentally friendly recycling of wastewater.

[0003] In existing technologies, the treatment of semiconductor polishing slurries mainly involves pretreatment (filtering large particulate impurities), chemical precipitation (flocculation and sedimentation), precision filtration (filtering extremely small silicon particles), pH adjustment, and finally disinfection. Only in this way can the semiconductor polishing slurry be recycled. However, there are still areas for improvement in the chemical precipitation process: the water with added flocculant needs to wait for it to settle, and the treated water must be discharged (new water can only be added after this process is complete). This process is too slow (to protect the flocculation and sedimentation). The recycling equipment needs to treat the wastewater generated and input into the equipment in real time. Therefore, the existing technology that uses gravity natural sedimentation is obviously not suitable for the concept of high-efficiency, real-time synchronous recycling. In order to prevent the polymer chains generated by flocculation and sedimentation from breaking under intense agitation, the chemical precipitation tanks that use flocculation and sedimentation often have a simple internal structure. Therefore, they do not have the function of simultaneously removing the sediment, and often require regular cleaning of the bottom of the tank. This greatly reduces the working efficiency of the equipment and is obviously not suitable for the high efficiency and environmental protection of recycling. Summary of the Invention

[0004] The purpose of this invention is to provide a semiconductor polishing slurry circulation treatment device to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a semiconductor polishing slurry circulation treatment device, comprising a chemical precipitation tank, a first connecting pipe, an ultrafiltration device, a second connecting pipe, a pH adjuster, a third connecting pipe, a sterilization tank, and a circulation outlet. The top of the chemical precipitation tank is respectively equipped with a flocculant inlet, a water inlet, and a motor. Inside the chemical precipitation tank, a rotating shaft and a stirrer are rotatably installed and directly driven by the motor. Multiple sets of sealing grooves are formed on the inner wall of the chemical precipitation tank. The inner wall of each sealing groove has an installation groove. A spring and a sealing plate are sealed and engaged inside the installation groove. The sealing plate is sealed and engaged with a sealing... In the sealing groove, multiple sets of filter boxes are fixedly installed on the outer periphery of the chemical precipitation tank. The filter boxes are connected to the sealing groove. Multiple sets of return pipes are fixedly connected to one side of the filter boxes. One end of the return pipe passes through the inner wall of the chemical precipitation tank and communicates with the inner cavity of the chemical precipitation tank. The inner cavity of the filter box has a first cavity and a second cavity. A filter screen is fixedly installed on the inner wall of the second cavity. A discharge port that passes through the filter box is opened at the bottom of the second cavity. A clamping plate is fixedly connected to the outer side of the sealing plate. A middle cylinder is fixedly installed on one side of the return pipe located on the inner wall of the chemical precipitation tank. The inner sealing sleeve of the middle cylinder is equipped with a spring and a piston.

[0006] In a preferred embodiment of the present invention, the first connecting pipe is fixedly connected to the bottom of the chemical precipitation tank and connected to the ultrafiltration device. A solenoid valve is installed on the outer surface of the first connecting pipe. A second connecting pipe is installed at the top of the ultrafiltration device. Another set of solenoid valves is installed on the outer surface of the second connecting pipe and connected to the pH regulator. The pH regulator is connected to the sterilization tank through the third connecting pipe.

[0007] As a preferred embodiment of the present invention, the flocculant inlet and the water inlet are respectively fixedly installed on the left and right sides of the top of the chemical precipitation tank, and are used to add flocculant and wastewater respectively. The agitator is configured as two sets and is installed circumferentially at equal intervals on the outer surface of the rotating shaft.

[0008] As a preferred embodiment of the present invention, the top view cross-sectional shape of the sealing groove is fan-shaped, the mounting groove is located on the inner wall of the sealing groove clockwise around the axis of rotation, the top view cross-sectional shape of the sealing plate is "L"-shaped, the side of the sealing plate protruding from the inner wall of the chemical precipitation tank is in sealing contact with the inner wall of the sealing groove, and the other side of the sealing plate is elastically supported inside the mounting groove by a spring.

[0009] In a preferred embodiment of the present invention, the volume of the second cavity is greater than that of the first cavity, and the clamping plate is sealed and clamped to the inner walls of the first and second cavities. The clamping plate can rotate counterclockwise around the axis of the rotating shaft and seal the discharge port.

[0010] As a preferred embodiment of the present invention, the discharge port is located on the side of the filter screen facing the card plate, and the interior of the return pipe is designed for unidirectional flow.

[0011] In a preferred embodiment of the present invention, the opening at one end of the middle cylinder facing the inner cavity of the chemical precipitation tank is larger than the opening at the other end, the two ends of the second spring are elastically connected to the middle cylinder and the piston respectively, and the piston is interference-fitted to the inner wall of the middle cylinder.

[0012] In a preferred embodiment of the present invention, the area of ​​the discharge port is smaller than the area of ​​the portion of the card plate located in the second cavity, and the rotation direction of the rotating shaft and the agitator is clockwise.

[0013] The beneficial effects of this invention are as follows:

[0014] 1. This device has been redesigned, changing the previous method of treating wastewater by static sedimentation after adding flocculant. It now features a motor-driven rotating shaft and agitator to stir the wastewater in the chemical sedimentation tank, allowing the flocculant to more fully and quickly form sediment. Increasing the motor speed and installing a filter box outside the chemical sedimentation tank creates a pushing force on the sealing plate from the high-speed rotating wastewater, opening the sealing groove and allowing the wastewater and sediment mixture to enter the filter box under centrifugal force. The sealing plate moves the clamping plate towards the filter screen, blocking the outlet and creating a unidirectional flow trend within the second chamber. The sediment is filtered and adheres to one side of the filter screen. The treated wastewater flows back into the chemical sedimentation tank through the return pipe. Thus, this device utilizes the agitator to generate a huge rotational thrust on the water, producing centrifugal force that breaks up the sediment and forces it through the filter box. The unidirectional thrust of the water flow quickly concentrates the sediment on the filter screen surface, greatly accelerating the collection speed of flocculation and sedimentation, and improving the device's working efficiency.

[0015] 2. Then, by setting a middle cylinder, spring two, and piston inside the return pipe, a one-way flow cleaning function is formed in the return pipe. When the wastewater is driven by the clockwise rotation of the agitator to generate a clockwise vortex, it pushes the sealing plate and opens the sealing groove. At this time, the inside of the return pipe is smooth, and the water flow can push the piston away from the middle cylinder. When the agitator stops, the displacement generated by the piston is pulled back by spring two. At this time, due to the sealing plate driving the clamping plate to reset under the action of spring one (the discharge port is reopened), the piston resets on the inner wall of the piston and pushes the water flow in the return pipe, driving the wastewater in the second chamber to backwash. On the one hand, it helps the sediment to be automatically discharged along the discharge port. On the other hand, the filter screen after backwashing achieves self-cleaning and does not need to be replaced, reducing the maintenance cost of the device.

[0016] 3. This device combines wastewater pretreatment and chemical precipitation using an added filter box, achieving a two-in-one function of physical filtration and chemical precipitation. When the motor drives the rotating shaft and agitator to rotate at high speed, the sealing plate is automatically pushed by the water flow and opens the sealing groove. At this time, the wastewater enters the filter box under centrifugal force and is filtered through the filter screen, completely eliminating the need for filter components such as grids during pretreatment, greatly reducing the complexity of the device and improving its practicality. Attached Figure Description

[0017] Figure 1 This is a top sectional view of the chemical precipitation tank of the present invention;

[0018] Figure 2 For the present invention Figure 1 Enlarged schematic diagram of the structure at point A;

[0019] Figure 3 For the present invention Figure 1 Enlarged schematic diagram of the structure at point B;

[0020] Figure 4 This is a schematic diagram of the overall appearance of the device of the present invention;

[0021] Figure 5 This is a schematic diagram of the external appearance of the chemical precipitation box of the present invention;

[0022] Figure 6 This is a schematic diagram showing the separation of the filter box, return pipe, spring one, sealing plate, clamping plate, filter screen, middle cylinder, spring two, and piston of the present invention.

[0023] Figure 7 This is a side sectional view of the chemical precipitation tank of the present invention;

[0024] Figure 8 This is a top view schematic diagram of the chemical precipitation tank of the present invention;

[0025] Figure 9 This is a bottom view of the filter box of the present invention.

[0026] In the diagram: 1. Chemical precipitation tank; 2. Connecting pipe 1; 3. Ultrafiltration equipment; 4. Connecting pipe 2; 5. pH regulator; 6. Connecting pipe 3; 7. Sterilization tank; 8. Circulation outlet; 9. Flocculant inlet; 10. Water inlet; 11. Motor; 12. Filter box; 121. Chamber 1; 122. Chamber 2; 13. Return pipe; 14. Rotating shaft; 15. Agitator; 16. Sealing groove; 17. Mounting groove; 18. Spring 1; 19. Sealing plate; 20. Clamping plate; 21. Filter screen; 22. Middle cylinder; 23. Spring 2; 24. Piston; 25. Discharge port. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] like Figures 1 to 9 As shown, this embodiment of the invention provides a semiconductor polishing slurry circulation treatment device, including a chemical precipitation tank 1, a first connecting pipe 2, an ultrafiltration device 3, a second connecting pipe 4, a pH adjuster 5, a third connecting pipe 6, a sterilization tank 7, and a circulation outlet 8. The top of the chemical precipitation tank 1 is respectively equipped with a flocculant inlet 9, a water inlet 10, and a motor 11. Inside the chemical precipitation tank 1, a rotating shaft 14 and a stirrer 15 are rotatably installed and directly driven by the motor 11. Multiple sets of sealing grooves 16 are formed on the inner wall of the chemical precipitation tank 1. Installation grooves 17 are formed on the inner wall of the sealing grooves 16. A spring 18 and a sealing plate 19 are sealed and engaged inside the installation groove 17. The sealing plate 19 is sealed and engaged in the sealing groove 16. Multiple sets of filter boxes 12 are fixedly installed on the outer periphery of the sedimentation tank 1. The filter boxes 12 are connected to the sealing groove 16. Multiple sets of return pipes 13 are fixedly connected to one side of the filter box 12. One end of the return pipe 13 passes through the inner wall of the chemical sedimentation tank 1 and is connected to the inner cavity of the chemical sedimentation tank 1. The inner cavity of the filter box 12 has a first cavity 121 and a second cavity 122. A filter screen 21 is fixedly installed on the inner wall of the second cavity 122. A discharge port 25 that passes through the filter box 12 is opened at the bottom of the second cavity 122. A clamping plate 20 is fixedly connected to the outer side of the sealing plate 19. A middle cylinder 22 is fixedly installed on one side of the return pipe 13 located on the inner wall of the chemical sedimentation tank 1. A spring 23 and a piston 24 are installed inside the sealing sleeve of the middle cylinder 22.

[0029] This device has been redesigned, changing the previous method of static sedimentation of wastewater after the addition of flocculant. A motor 11 drives a rotating shaft 14 and a stirrer 15 to rotate, agitating the wastewater in the chemical sedimentation tank 1. This allows the flocculant in contact with the wastewater to form sediment more fully and quickly. The motor 11 speed is increased, and a filter box 12 is installed outside the chemical sedimentation tank 1. The high-speed rotating wastewater generates a thrust on the sealing plate 19, opening the sealing groove 16 and allowing the mixture of wastewater and sediment to enter the filter box 12 under centrifugal force. The sealing plate 19 then drives the clamping plate 20. The water moves towards the filter screen 21, blocking the outlet 25, and forming a unidirectional flow trend in the inner cavity of the second chamber 122. The sediment is filtered and adheres to one side of the filter screen 21. The treated wastewater flows back to the inner cavity of the chemical precipitation tank 1 through the return pipe 13. In this way, the device can use the agitator 15 to generate a huge rotational thrust on the water, producing a centrifugal effect, breaking up the sediment, and making it all pass through the filter tank 12. The unidirectional thrust generated by the water flow quickly concentrates the sediment on the surface of the filter screen 21, thereby greatly accelerating the collection speed of flocculation sedimentation and helping to improve the working efficiency of the device.

[0030] Then, by setting a middle cylinder 22, spring 23 and piston 24 inside the return pipe 13, a one-way flow cleaning function is formed in the return pipe 13. When the wastewater generates a clockwise vortex under the clockwise rotation of the agitator 15, it pushes the sealing plate 19 and opens the sealing groove 16. At this time, the inside of the return pipe 13 is smooth, and the water flow can push the piston 24 away from the middle cylinder 22. When the agitator 15 stops rotating, the displacement generated by the piston 24 is pulled back by spring 23. At this time, because the sealing plate 19 drives the clamping plate 20 to reset under the action of spring 18 (the discharge port 25 is reopened), the piston 24 resets on the inner wall of the piston 24 and pushes the water flow in the return pipe 13, which drives the wastewater in the inner cavity of the second chamber 122 to backwash. On the one hand, it helps the sediment to be automatically discharged along the discharge port 25. On the other hand, the filter screen 21 after backwashing achieves self-cleaning and does not need to be replaced, reducing the maintenance cost of the device.

[0031] Among them, the first connecting pipe 2 is fixedly connected to the bottom of the chemical precipitation tank 1 and connected to the ultrafiltration equipment 3. A solenoid valve is installed on the outer surface of the first connecting pipe 2. The second connecting pipe 4 is installed at the top of the ultrafiltration equipment 3. Another set of solenoid valves is installed on the outer surface of the second connecting pipe 4 and connected to the pH regulator 5. The pH regulator 5 is connected to the sterilization tank 7 through the third connecting pipe 6.

[0032] This device integrates a chemical precipitation tank 1, an ultrafiltration device 3, a pH regulator 5, and a sterilization tank 7, realizing the filtration, precipitation, ultrafiltration, pH adjustment, and sterilization of wastewater, thus completing a closed loop of wastewater recycling treatment.

[0033] The flocculant inlet 9 and the water inlet 10 are fixedly installed on the left and right sides of the top of the chemical precipitation tank 1, respectively, and are used to add flocculant and wastewater. The agitator 15 is set in two groups and is installed circumferentially at equal intervals on the outer surface of the rotating shaft 14.

[0034] The flocculant inlet 9 is used to add flocculant, the water inlet 10 is responsible for introducing polishing and grinding wastewater, and the agitator 15 rotates under the drive of the motor 11 and the rotating shaft 14 to stir the inner cavity of the chemical precipitation tank 1, so that impurities such as silicon particles in the wastewater react with the flocculant to produce precipitates.

[0035] Among them, the top view cross-section of the sealing groove 16 is fan-shaped, the mounting groove 17 is located on the inner wall of the sealing groove 16 clockwise around the axis of the rotating shaft 14, the top view cross-section of the sealing plate 19 is "L" shaped, the side of the sealing plate 19 protruding from the inner wall of the chemical precipitation tank 1 seals against the inner wall of the sealing groove 16, and the other side of the sealing plate 19 is elastically supported inside the mounting groove 17 by a spring-18.

[0036] The sealing plate 19 can rotate along the inner wall of the sealing groove 16 to form a seal, or open the sealing groove 16. This device combines the pretreatment of wastewater and chemical precipitation by using the added filter box 12, realizing the two-in-one function of physical filtration and chemical precipitation. When the motor 11 drives the rotating shaft 14 and the agitator 15 to rotate at high speed, the sealing plate 19 is automatically pushed by the water flow and the sealing groove 16 is opened. At this time, the wastewater enters the filter box 12 under centrifugal action and is filtered through the filter screen 21. This completely eliminates the need for filter components such as the grid during pretreatment, greatly reducing the complexity of the device and improving its practicality.

[0037] Among them, the volume of the second cavity 122 is greater than that of the first cavity 121. The clamping plate 20 is sealed and clamped to the inner wall of the first cavity 121 and the second cavity 122. The clamping plate 20 can rotate counterclockwise around the axis of the rotating shaft 14 and seal the discharge port 25.

[0038] The filter screen 21 installed in the inner cavity of the second cavity 122 is responsible for filtering the wastewater and sediment passing through it. This design can effectively filter sediments whose polymer chains are broken due to high-speed rotation.

[0039] Among them, the discharge port 25 is located on the side of the filter screen 21 facing the card plate 20, and the interior of the return pipe 13 is designed for unidirectional flow.

[0040] The discharge port 25 is located near the filter surface of the filter screen 21. After the filter screen 21 has completed filtration, the filtered impurities can be automatically discharged through the discharge port 25, thus completing the automatic cleaning function of the device.

[0041] Among them, the opening of one end of the middle cylinder 22 facing the inner cavity of the chemical precipitation tank 1 is larger than the opening of the other end. The two ends of the spring 23 are elastically connected to the middle cylinder 22 and the piston 24 respectively. The piston 24 is interference-fitted to the inner wall of the middle cylinder 22.

[0042] The cooperation between the middle cylinder 22 and the piston 24 forms a one-way flow function inside the return pipe 13 (the water flow can only enter the return pipe 13 through the filter box 12). This function can prevent water in the inner cavity of the chemical precipitation tank 1 from entering the filter box 12 and prevent wastewater from leaking through the outlet 25 when the sealing groove 16 is closed.

[0043] Among them, the area of ​​the discharge port 25 is smaller than the area of ​​the portion of the card plate 20 located in the second cavity 122, and the rotation of the rotating shaft 14 and the agitator 15 is clockwise.

[0044] The large area of ​​the plate 20 can be rotated to abut against the filter screen 21 to form a seal, thereby sealing the outlet 25 and preventing wastewater from leaking through the outlet 25 when being filtered by the filter screen 21.

[0045] Working principle:

[0046] When the device is working, the polishing and grinding wastewater is poured into the inner cavity of the chemical precipitation tank 1 through the water inlet 10, and the motor 11 is started, which drives the rotating shaft 14 and the agitator 15 to rotate clockwise. The speed is set to A to stir the wastewater. The flocculant is added into the chemical precipitation tank 1 through the flocculant inlet 9 and fully contacts and reacts with the wastewater to produce a large amount of precipitate. At this time, the motor 11 is controlled and the speed is set to B, B>A. At this time, the sealing plate 19 rotates smoothly under the push of the rotating water flow and compresses the spring 18, and the wastewater begins to enter the filter box 12.

[0047] Then, the sealing plate 19 drives the clamping plate 20 to rotate clockwise, so that one side of the clamping plate 20 abuts against the filter screen 21 to form a seal. The precipitate stirred by the stirrer 15 in the chemical precipitation tank 1 enters the inner cavity of the filter tank 12 under centrifugal action, and passes through the first cavity 121, the second cavity 122 and the filter screen 21 in sequence. The precipitate is filtered and intercepted by the filter screen 21. The filtered wastewater passes through the filter screen 21 and enters the return pipe 13, pushing the piston 24 to move towards the side of the tension spring 23 until the piston 24 leaves the inner wall of the middle cylinder 22. The wastewater returns to the inner cavity of the chemical precipitation tank 1 through the middle cylinder 22.

[0048] Then, the motor 11 is turned off, the shaft 14 and the agitator 15 stop stirring the inner cavity of the chemical precipitation tank 1, the wastewater stops rotating and no longer generates centrifugal force, the sealing plate 19 loses the rotational thrust of the wastewater and automatically resets under the action of spring 18, resealing the sealing groove 16. At the same time, the clamping plate 20 resets and the discharge port 25 opens. At this time, in the return pipe 13, the piston 24 resets under the rebound pull of spring 23 and pushes the water in the inner cavity of the return pipe 13 to flow in the opposite direction, rinsing the precipitate filtered by the installation tank 17. The precipitate is discharged from the discharge port 25.

[0049] Finally, the wastewater stored in the inner cavity of the chemical precipitation tank 1 undergoes flocculation sedimentation, filtration, and discharge treatment to remove a large number of impurities (silicon particles, etc.). The solenoid valve on the first connecting pipe 2 is opened, and the treated wastewater is pumped into the ultrafiltration device 3 through the water pump at the bottom of the chemical precipitation tank 1 to filter out even finer silicon particles. The wastewater then passes through the ultrafiltration device 3 and the second connecting pipe 4 into the pH adjuster 5 to adjust the pH value. Finally, it enters the sterilization tank 7 through the third connecting pipe 6 to complete the final sterilization. Finally, the treated grinding fluid is recycled through the circulation outlet 8.

[0050] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0051] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A semiconductor polishing slurry circulation treatment device, comprising a chemical precipitation tank (1), a first connecting pipe (2), an ultrafiltration device (3), a second connecting pipe (4), a pH regulator (5), a third connecting pipe (6), a sterilization tank (7), and a circulation outlet (8), wherein the top of the chemical precipitation tank (1) is respectively equipped with a flocculant inlet (9), a water inlet (10), and a motor (11), and the interior of the chemical precipitation tank (1) is rotatably equipped with a rotating shaft (14) and a stirrer (15), which are directly driven by the motor (11), characterized in that: The inner wall of the chemical precipitation tank (1) has multiple sets of sealing grooves (16), and the inner wall of the sealing grooves (16) has an installation groove (17). The installation groove (17) is sealed with a spring (18) and a sealing plate (19). The sealing plate (19) is sealed in the sealing groove (16). Multiple sets of filter boxes (12) are fixedly installed on the outer circumference of the chemical precipitation tank (1). The filter boxes (12) are connected to the sealing grooves (16). Multiple sets of return pipes (13) are fixedly connected to one side of the filter boxes (12). One end of the return pipe (13) passes through the inner wall of the chemical precipitation tank (1) and is connected to the inner cavity of the chemical precipitation tank (1). The inner cavity of the filter box (12) has a first cavity (121) and a second cavity (122). The inner wall of the second cavity (122) is fixedly installed with a filter screen (21). The bottom of the second chamber (122) is provided with a discharge port (25) that passes through the filter box (12). The outer side of the sealing plate (19) is fixedly connected with a clamping plate (20). The return pipe (13) is located on one side of the inner wall of the chemical precipitation tank (1) and a middle cylinder (22) is fixedly installed. The inner sealing sleeve of the middle cylinder (22) is provided with a spring (23) and a piston (24). The top view cross-section of the sealing groove (16) is fan-shaped. The mounting groove (17) is located on the inner wall of the sealing groove (16) clockwise around the axis of the rotating shaft (14). The top view cross-section of the sealing plate (19) is "L"-shaped. The side of the sealing plate (19) that protrudes from the inner wall of the chemical precipitation tank (1) is sealed and abuts against the inner wall of the sealing groove (16). The other side of the sealing plate (19) is elastically supported inside the mounting groove (17) by a spring (18).

2. The semiconductor polishing slurry circulation treatment equipment according to claim 1, characterized in that: The first connecting pipe (2) is fixedly connected to the bottom of the chemical precipitation tank (1) and connected to the ultrafiltration device (3). A solenoid valve is installed on the outer surface of the first connecting pipe (2). A second connecting pipe (4) is installed at the top of the ultrafiltration device (3). Another set of solenoid valves is installed on the outer surface of the second connecting pipe (4) and connected to the pH regulator (5). The pH regulator (5) is connected to the sterilization box (7) through the third connecting pipe (6).

3. The semiconductor polishing slurry circulation treatment equipment according to claim 1, characterized in that: The flocculant inlet (9) and water inlet (10) are fixedly installed on the left and right sides of the top of the chemical precipitation tank (1), respectively, and are used to add flocculant and wastewater. The agitator (15) is set in two groups and is circumferentially and equidistantly installed on the outer surface of the rotating shaft (14).

4. The semiconductor polishing slurry circulation treatment equipment according to claim 3, characterized in that: The volume of the second cavity (122) is greater than that of the first cavity (121). The clamping plate (20) is sealed and clamped to the inner wall of the first cavity (121) and the second cavity (122). The clamping plate (20) can rotate counterclockwise around the axis of the rotating shaft (14) and seal the discharge port (25).

5. The semiconductor polishing slurry circulation treatment equipment according to claim 4, characterized in that: The discharge port (25) is located on the side of the filter screen (21) facing the card plate (20), and the interior of the return pipe (13) is designed for unidirectional flow.

6. The semiconductor polishing slurry circulation treatment equipment according to claim 5, characterized in that: The opening at one end of the middle cylinder (22) facing the inner cavity of the chemical precipitation tank (1) is larger than the opening at the other end. The two ends of the second spring (23) are elastically connected to the middle cylinder (22) and the piston (24) respectively. The piston (24) is interference-fitted to the inner wall of the middle cylinder (22).

7. The semiconductor polishing slurry circulation treatment equipment according to claim 6, characterized in that: The area of ​​the discharge port (25) is smaller than the area of ​​the portion of the card plate (20) located in the second cavity (122), and the rotation of the shaft (14) and the agitator (15) is clockwise.

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