Polysilicon production wastewater treatment equipment

Abstract

This invention relates to equipment for treating polysilicon production wastewater, including a wastewater storage tank, a silicon-containing wastewater screw pump, a PAM dosing unit, a dewatering machine, a sludge conveyor, and a pressure stacking system. The wastewater storage tank and the dewatering machine are connected via a silicon-containing wastewater conveying assembly. This invention relates to the field of silicon-containing wastewater treatment technology. This polysilicon production wastewater treatment equipment can automatically filter the silicon-containing wastewater during the conveying process without stopping the agitation, effectively separating the silicon-containing wastewater from sewage. Treatment can be carried out without stopping the system, and the height of the filter ring is adjustable at any time without interfering with the normal agitation of the upper agitation assembly.

Description

Technical Field

[0001] This invention relates to the field of silicon-containing wastewater treatment technology, specifically to equipment for treating polysilicon production wastewater. Background Technology

[0002] With the advancement of technology and the increasing awareness of environmental protection, the production and use of solar photovoltaic materials have entered a stage of rapid growth. As a crucial raw material for solar photovoltaic materials, polycrystalline silicon has also seen a rapid increase in industrial production demand. Polycrystalline silicon production primarily utilizes multi-wire cutting technology. During the cutting process, approximately 50% of the silicon material mixes into the cutting fluid, which is composed of polyethylene glycol cutting fluid and silicon carbide abrasive powder. This results in the micro-powder composition, particle size, and hardness of the cutting fluid failing to meet standards, leading to decreased cutting performance and the inability to reuse the material. Therefore, the old cutting fluid needs to be continuously drained and replenished with new cutting fluid during the cutting process, generating a large amount of cutting wastewater. This wastewater from polycrystalline silicon production contains high concentrations of fluoride ions, chloride ions, and various heavy metal ions. Direct discharge would cause serious environmental pollution. The exhaust gas from polycrystalline silicon production mainly contains large amounts of HCl, chlorosilanes (SiHCl3, SiH2Cl2, SiCl4), H2, and N2. Because chlorosilanes are highly susceptible to hydrolysis, alkaline washing methods such as dilute NaOH solution and lime milk are often used.

[0003] Existing silicon-containing wastewater treatment equipment cannot effectively filter silicon-containing wastewater to separate the internal sewage and solid residues. Therefore, a device that can effectively filter silicon-containing wastewater while stirring and conveying it is proposed, which can quickly perform preliminary separation of silicon and water. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a treatment device for polysilicon production wastewater, which solves the problems mentioned above.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution: a polysilicon production wastewater treatment device, including a wastewater storage tank, a silicon-containing wastewater screw pump, a PAM dosing unit and a dewatering machine, wherein the wastewater storage tank and the dewatering machine are connected by a silicon-containing wastewater conveying component;

[0006] The silicon-containing wastewater conveying assembly includes a stirring and conveying box. The bottom of the inner cavity of the stirring and conveying box is connected to a wastewater storage tank through a sludge inlet pipe, and the top of the inner cavity of the stirring and conveying box is connected to a dewatering machine through a sludge outlet pipe.

[0007] The upper and lower cavities of the mixing and conveying box are equipped with mixing components. A filter press ring, driven by a lifting mechanism, is slidably connected to the inner cavity of the mixing and conveying box. A filter press cloth is fixedly connected to the inner cavity of the filter press ring. Multiple support rods, abutting the top of the filter press cloth, are fixedly connected to the inner cavity of the filter press ring. The connection points of the multiple support rods form a groove adapted to the mixing components. A power box is fixedly connected to one side of the filter press ring. Two clamping plates are movably connected to the inner cavity of the power box via a movable groove. The two clamping plates are respectively fixedly connected to both sides of the filter press cloth, forming a sealing groove adapted to the surface of the mixing blades. A double-rod cylinder is fixedly connected to the inner cavity of the power box. Push plates, which are fixedly connected to the two piston rods of the double-rod cylinder, are fixedly connected to one side of each of the two clamping plates. Multiple evenly arranged vibrating motors are fixedly connected to the surface of the filter ring. During operation, silica-containing wastewater is input into the mixing and conveying box through the sludge inlet pipe. The silica-containing wastewater gradually accumulates from bottom to top. Then, the two rotating shafts drive the stirring blades to rotate, thoroughly mixing the silica-containing wastewater. The silica-containing wastewater gradually accumulates until it rises above the sludge outlet pipe. After settling for a period of time, the upper drive motor is stopped, and the upper rotating shaft rotates to its fixed position. The rotation stops at a fixed angle. Then, the electric hoist lowers the rope, causing the filter ring to gradually descend within the mixing and conveying box. Initially, due to the thrust of the silica-containing wastewater, the filter ring cannot descend effectively. At this point, the vibration motor starts, causing the filter ring to vibrate. Wastewater seeps out through the filter cloth inside the box, while the silica-containing wastewater remains below. Support rods ensure the strength of the filter cloth. The filter ring then gradually descends to the side of the mixing blade at the bottom of the upper rotating shaft. At this point, the clamping plates are positioned on both sides of the mixing blade. The double-rod cylinder is activated, causing two push plates to move inward, clamping the two clamping plates onto the surface of the mixing blade, forming a complete annular filter press. The filter cloth is then continuously vibrated by a vibrating motor. At this time, the sewage inside the silica-containing wastewater is at the top. Different extraction pipes are connected to the sludge pump through the solenoid valve to extract the sewage at different heights. This effectively extracts the filtered sewage without extracting too much silica-containing wastewater. The silica-containing wastewater is then discharged through the sludge outlet pipe at the bottom. During the transportation process, the silica-containing wastewater can be automatically filtered without stopping the stirring, effectively separating the silica-containing wastewater and sewage. The process can be carried out without stopping the machine, and the height of the filter ring can be adjusted at any time without interfering with the normal stirring work of the upper stirring components.

[0008] As a further aspect of the present invention: the stirring assembly includes a rotating shaft rotatably connected to the inner cavity of the stirring and conveying box and driven by a drive motor. The inner cavity of the stirring box is fixedly connected to support rings that are rotatably connected to the rotating shaft. Stirring blades are fixedly connected to the surface of the rotating shaft. Two stirring assemblies are provided and symmetrically distributed in the upper and lower parts of the stirring and conveying box. By setting the upper and lower stirring assemblies, a segmented stirring layout is formed when normal stirring can be ensured. The upper stirring assembly can be stopped. A slot is formed between the multiple support rods to match the rotating shaft and the stirring blades. When the rotating shaft rotates to a fixed angle, the filter ring can be smoothly raised and lowered.

[0009] As a further embodiment of the present invention: the mud discharge pipe is disposed above the support ring.

[0010] As a further aspect of the present invention: the surface of the mixing and conveying box located behind the upper rotating shaft is connected to multiple extraction pipes that are connected to the sludge pump. Multiple extraction pipes are provided, and they are controlled in pairs by solenoid valves. By controlling different extraction pipes to connect with the sludge pump through the solenoid valves, extraction can be performed at different heights, which can effectively extract the filtered sewage without extracting too much silicon-containing wastewater.

[0011] As a further aspect of the present invention: the lifting mechanism includes an electric hoist fixed to the top of the mixing and conveying box. The transmission end of the electric hoist is fixedly connected to the top of the filter ring via a pull rope. The height of the filter ring in the inner cavity of the mixing and conveying box is adjusted by the electric hoist driving the pull rope to lift and lower.

[0012] As a further aspect of the present invention: the ends of the plurality of support rods are all fixedly connected with notched rings sleeved on the surface of the rotating shaft, and the notched rings are movably disposed with respect to the surface of the drive shaft.

[0013] As a further aspect of the present invention: the inner cavity of the movable groove is fixedly connected to the surface of the clamping plate through a sealing gasket. With the setting of the sealing gasket, the clamping plate can rotate and open freely while preventing external silicon-containing wastewater from entering the power box from the movable groove.

[0014] As a further aspect of the present invention: the inner cavity of the stirring and conveying box is separated by a filter pressure ring into a lower silicon-containing wastewater cavity and an upper sewage cavity.

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] This invention can automatically filter silicon-containing wastewater during the conveying process without stopping the stirring, effectively performing preliminary separation of the silicon-containing wastewater. It can be processed without stopping the machine, and the height of the filter ring can be adjusted at any time without interfering with the normal stirring operation of the upper stirring component.

[0017] In this invention, the filter press ring gradually descends within the inner cavity of the mixing and conveying box. At this point, due to the thrust of the silicon-containing wastewater, the filter press ring cannot descend effectively. At this time, the vibration motor is started, driving the filter press ring to vibrate. Through the filter cloth in the inner cavity, the wastewater seeps out, while the silicon remains at the bottom. The strength of the filter cloth is ensured by the support rod.

[0018] In this invention, the filter press ring gradually descends to the side of the stirring blade at the bottom of the upper rotating shaft. At this time, the clamping plates are located on both sides of the stirring blade. The double-rod cylinder is activated to drive the two push plates to move inward, causing the two clamping plates to clamp the surface of the stirring blade, forming a complete annular filter press cloth.

[0019] This invention controls different extraction pipes to connect with the sludge pump via electromagnetic valves, allowing extraction at different heights. This effectively extracts the filtered wastewater without extracting excessive amounts of silicon-containing wastewater. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the present invention;

[0021] Figure 2 This is a cross-sectional view of the structure of the present invention;

[0022] Figure 3 This is a top view of the filter ring structure of the present invention;

[0023] Figure 4 This is a schematic diagram of the filter ring clamping plate of the present invention in the open state;

[0024] Figure 5 For the present invention Figure 3 A magnified view of a portion of point A in the middle.

[0025] In the diagram: 1. Mixing and conveying box; 2. Electric hoist; 3. Support ring; 4. Drive motor; 5. Rotating shaft; 6. Mixing blade; 7. Mud inlet pipe; 8. Mud outlet pipe; 9. Pull rope; 10. Filter press ring; 11. Extraction pipe; 12. Filter press cloth; 13. Support rod; 14. Vibration motor; 15. Power box; 16. Movable groove; 17. Sealing gasket; 19. Double rod cylinder; 20. Clamping plate; 21. Push plate; 22. Sealing groove. Detailed Implementation

[0026] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0027] Please see Figure 1-5The present invention provides a technical solution: a polysilicon production wastewater treatment device, including a wastewater storage tank, a silicon-containing wastewater screw pump, a PAM dosing unit and a dewatering machine, wherein the wastewater storage tank and the dewatering machine are connected by a silicon-containing wastewater conveying component;

[0028] The silicon-containing wastewater conveying assembly includes a stirring and conveying box 1. The bottom of the inner cavity of the stirring and conveying box 1 is connected to the wastewater storage tank through a sludge inlet pipe 7, and the top of the inner cavity of the stirring and conveying box 1 is connected to the dewatering machine through a sludge outlet pipe 8.

[0029] A mixing assembly is installed in both the upper and lower cavities of the mixing and conveying box 1. A filter ring 10 driven by a lifting mechanism is slidably connected to the inner cavity of the mixing and conveying box 1. A filter cloth 12 is fixedly connected to the inner cavity of the filter ring 10. Multiple support rods 13 that abut against the top of the filter cloth 12 are fixedly connected to the inner cavity of the filter ring 10. The connection of the multiple support rods 13 forms a slot adapted to the mixing assembly. A power box 15 is fixedly connected to one side of the filter ring 10. Two clamping plates 20 are movably connected to the inner cavity of the power box 15 through a movable groove 16. The two clamping plates 20 are fixedly connected to both sides of the filter cloth 12 respectively. The two clamping plates 20 form a sealing groove 22 adapted to the surface of the mixing blade 6. A double-rod cylinder 19 is fixedly connected to the inner cavity of the box 15. Push plates 21, which are fixedly connected to the two piston rods of the double-rod cylinder 19, are fixedly connected to one side of each of the two clamping plates 20. Multiple evenly arranged vibrating motors 14 are fixedly connected to the surface of the filter ring 10. During use, silica-containing wastewater is input into the mixing and conveying box 1 from the sludge inlet pipe 7. The silica-containing wastewater gradually accumulates from bottom to top. Then, the two rotating shafts 5 drive the stirring blades 6 to rotate, thoroughly mixing the silica-containing wastewater. The silica-containing wastewater gradually accumulates until it rises above the sludge outlet pipe 8. After settling for a period of time, the upper drive motor 4 is stopped, and the upper rotating shaft 5 rotates to a fixed angle and stops. Stop the rotation, and then lower the pull rope 9 using the electric hoist 2. The filter ring 10 gradually descends inside the mixing and conveying box 1. At this time, due to the thrust of the silicon-containing wastewater, the filter ring 10 cannot descend effectively. At this time, the vibration motor starts, driving the filter ring 10 to vibrate. Through the filter cloth 12 in the inner cavity, the sewage seeps out, and the silicon-containing wastewater remains below. The support rod 13 ensures the strength of the filter cloth 12. Then the filter ring 10 gradually descends to the side of the stirring blade 6 at the bottom of the upper rotating shaft 5. At this time, the clamping plates 20 are located on both sides of the stirring blade 6. Start the double-rod cylinder 19 to drive the two push plates 21 to move inward, driving the two clamping plates 20 to clamp the surface of the stirring blade 6, forming a A complete annular filter cloth 12 is used, and then a vibrating motor 14 continuously drives the filter cloth 12 to vibrate. At this time, the sewage inside the silicon-containing wastewater is at the top. Different extraction pipes 11 are connected to the sludge pump through the solenoid valve to extract at different heights, which can effectively extract the filtered sewage without extracting too much silicon-containing wastewater. Then the silicon-containing wastewater is output through the sludge outlet pipe 8 at the bottom. During the transportation process, the silicon-containing wastewater can be automatically filtered without stopping the stirring, and the silicon-containing wastewater and sewage can be effectively initially separated. The process can be carried out without stopping the machine, and the height of the filter ring 10 can be adjusted at any time without interfering with the normal stirring work of the upper stirring component.

[0030] The mixing assembly includes a rotating shaft 5 rotatably connected to the inner cavity of the mixing and conveying box 1 and driven by a drive motor 4. The inner cavity of the mixing and conveying box 1 is fixedly connected to support rings 3, which are rotatably connected to the rotating shaft 5. The surface of the rotating shaft 5 is fixedly connected to stirring blades 6. There are two mixing assemblies, which are symmetrically distributed in the upper and lower parts of the mixing and conveying box 1. By setting the upper and lower mixing assemblies, a segmented mixing layout is formed when normal mixing can be ensured. The upper mixing assembly can be stopped. Multiple support rods 13 form a groove that is adapted to the rotating shaft 5 and the stirring blades 6. When the rotating shaft 5 rotates to a fixed angle, the filter ring 10 can be smoothly raised and lowered.

[0031] The mud discharge pipe 8 is located above the support ring 3.

[0032] The surface of the mixing and conveying box 1 located behind the upper rotating shaft 5 is connected to multiple extraction pipes 11 that are connected to the sludge pump. Multiple extraction pipes 11 are provided, and they are controlled in pairs by solenoid valves. By controlling different extraction pipes 11 to connect with the sludge pump through the solenoid valves, extraction can be carried out at different heights, which can effectively extract the filtered sewage without extracting too much silicon-containing wastewater.

[0033] The lifting mechanism includes an electric hoist 2 fixed to the top of the mixing and conveying box 1. The transmission end of the electric hoist 2 is fixedly connected to the top of the filter ring 10 via a pull rope 9. The electric hoist 2 drives the pull rope 9 to lift and lower, thereby adjusting the height of the filter ring 10 in the inner cavity of the mixing and conveying box 1.

[0034] Each of the multiple support rods 13 has a notched ring fixedly connected to its end, which is sleeved on the surface of the rotating shaft 5. The notched ring is movably positioned relative to the surface of the drive shaft.

[0035] The inner cavity of the movable groove 16 is fixedly connected to the surface of the clamping plate 20 through the sealing gasket 17. With the setting of the sealing gasket 17, the clamping plate 20 can rotate and open freely while preventing external silicon-containing wastewater from entering the power box 15 from the movable groove 16.

[0036] The inner cavity of the mixing and conveying box 1 is separated by a filter pressure ring 10, which separates the lower silicon-containing wastewater cavity from the upper sewage cavity.

[0037] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. Wastewater treatment equipment for polysilicon production, comprising a wastewater storage tank, a silicon-containing wastewater screw pump, a PAM dosing unit, and a dewatering machine, characterized in that: The wastewater storage tank and the dewatering machine are connected by a silicon-containing wastewater conveying assembly. The silicon-containing wastewater conveying assembly includes a stirring and conveying box (1), the bottom of the inner cavity of the stirring and conveying box (1) is connected to the wastewater storage tank through a sludge inlet pipe (7), and the top of the inner cavity of the stirring and conveying box (1) is connected to the dewatering machine through a sludge outlet pipe (8). The upper and lower cavities of the mixing and conveying box (1) are equipped with mixing components. A filter ring (10) driven by a lifting mechanism is slidably connected to the inner cavity of the mixing and conveying box (1). A filter cloth (12) is fixedly connected to the inner cavity of the filter ring (10). Multiple support rods (13) that abut against the top of the filter cloth (12) are fixedly connected to the inner cavity of the filter ring (10). The connection of the multiple support rods (13) forms a slot adapted to the mixing components. A power box (15) is fixedly connected to one side of the filter ring (10). The inner cavity of the power box (15) is... The cavity is movably connected to two clamping plates (20) via a movable groove (16). The two clamping plates (20) are fixedly connected to both sides of the filter cloth (12). The two clamping plates (20) form a sealing groove (22) that is adapted to the surface of the stirring blade (6). The inner cavity of the power box (15) is fixedly connected to a double-rod cylinder (19). One side of each of the two clamping plates (20) is fixedly connected to a push plate (21) that is fixedly connected to the two piston rods of the double-rod cylinder (19). The surface of the filter ring (10) is fixedly connected to multiple evenly arranged vibration motors (14).

2. The polysilicon production wastewater treatment equipment according to claim 1, characterized in that: The stirring assembly includes a rotating shaft (5) rotatably connected to the inner cavity of the stirring and conveying box (1) and driven by a drive motor (4). The inner cavity of the stirring and conveying box (1) is fixedly connected with support rings (3) that are rotatably connected to the rotating shaft (5). Stirring blades (6) are fixedly connected to the surface of the rotating shaft (5). There are two stirring assemblies, which are symmetrically distributed on the upper and lower sides of the stirring and conveying box (1).

3. The polysilicon production wastewater treatment equipment according to claim 1, characterized in that: The mud discharge pipe (8) is located above the support ring (3).

4. The polysilicon production wastewater treatment equipment according to claim 1, characterized in that: The surface of the mixing and conveying box (1) located behind the upper rotating shaft (5) is connected to multiple extraction pipes (11) that are connected to the mud pump. Multiple extraction pipes (11) are provided, and they are controlled by solenoid valves in pairs.

5. The polysilicon production wastewater treatment equipment according to claim 1, characterized in that: The lifting mechanism includes an electric hoist (2) fixed to the top of the mixing and conveying box (1), and the transmission end of the electric hoist (2) is fixedly connected to the top of the filter press ring (10) by a pull rope (9).

6. The polysilicon production wastewater treatment equipment according to claim 1, characterized in that: Each of the multiple support rods (13) has a notched ring fixedly connected to its end on the surface of the rotating shaft (5), and the notched ring is movably connected to the surface of the drive shaft.

7. The polysilicon production wastewater treatment equipment according to claim 1, characterized in that: The inner cavity of the movable groove (16) is fixedly connected to the surface of the clamp (20) through a sealing gasket (17).

8. The polysilicon production wastewater treatment equipment according to claim 1, characterized in that: The inner cavity of the mixing and conveying box (1) is separated by a filter press ring (10) into a lower silicon-containing wastewater cavity and an upper sewage cavity.

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