Diamond wire cutting liquid regeneration and reuse system

Abstract

The utility model relates to the technical field of environmental protection, in particular to a diamond wire cutting liquid regenerating and recycling system. Comprising a first filtering device used for collecting cutting waste liquid discharged by an external diamond wire cutting production line, a sludge box communicated with the first filtering device, a second filtering device communicated with the sludge box and a clean liquid collecting box used for supplying cutting clean liquid to the diamond wire cutting production line. Cutting clean liquid filtered by the first filtering device is conveyed to the clean liquid collecting box; the first filtering device comprises a first filtering assembly used for filtering cutting waste liquid to obtain cutting clean liquid, the second filtering device comprises a second filtering assembly used for filtering primary cutting liquid output by the sludge box, and filtering parameters of the first filtering assembly are different from filtering parameters of the second filtering assembly; the cutting waste liquid can be completely and efficiently recycled through the first filtering assembly of the first filtering device and the second filtering assembly of the second filtering device.

Description

Technical Field

[0001] The utility model relates to the technical field of environmental protection, in particular to a regeneration and reuse system for a diamond wire cutting fluid. Background Art

[0002] For a diamond wire cutting machine used for slicing single crystal silicon rods or polycrystalline silicon rods, a cutting fluid is required to lubricate and cool the diamond wire, and to clean and disperse silicon powder particles on the wire. During the cutting process, the silicon powder concentration in the cutting fluid needs to be strictly controlled. In the prior art, the method of replacing the cutting fluid is to completely replace the entire tank of cutting fluid with newly prepared cutting fluid after one batch of cutting is completed. The newly prepared cutting fluid is a mixture of water and cutting stock solution, which is preheated to a certain temperature and then added to the cutting fluid tank for a new round of feeding and cutting.

[0003] When polycrystalline silicon is sliced with a diamond wire, in order to avoid a large amount of heat generated by long-term friction causing damage to the diamond wire, it is necessary to continuously spray the cutting fluid on the polycrystalline silicon during the cutting process for cooling. The conventional cutting fluid recovery device directly recovers the cutting waste liquid, with low recovery and utilization efficiency, and cannot filter and collect more silicon wafer particles in the cutting waste liquid, resulting in a large amount of waste of silicon resources. Summary of the Utility Model

[0004] In order to overcome the deficiencies in the prior art, the purpose of the utility model is to provide a regeneration and reuse system for a diamond wire cutting fluid, aiming at a diamond wire cutting fluid production line with a large processing volume requirement, achieving 100% solid-liquid separation of the diamond wire cutting waste liquid and silicon wafer particles, improving the reuse quality of the cutting waste liquid and the recovery and utilization of silicon resources, and completely and efficiently recovering the cutting waste liquid.

[0005] To achieve the above purpose, the technical solution of a regeneration and reuse system for a diamond wire cutting fluid of the utility model is: a regeneration and reuse system for a diamond wire cutting fluid, including a first filtering device for collecting the cutting waste liquid discharged from an external diamond wire cutting production line, a sludge tank communicated with the first filtering device, a second filtering device communicated with the sludge tank, and a clean liquid collection tank for supplying clean cutting fluid to the diamond wire cutting production line. The clean cutting fluid filtered by the first filtering device is conveyed to the clean liquid collection tank; the first filtering device includes a first filtering component for filtering the cutting waste liquid to obtain clean cutting fluid, the second filtering device includes a second filtering component for filtering the primary cutting fluid output from the sludge tank, and the filtering parameters of the first filtering component are different from those of the second filtering component.

[0006] Furthermore, the second filtering device is communicated with the first filtering device, and the clean cutting fluid filtered by the second filtering device is input into the first filtering device for filtering.

[0007] Furthermore, the first filtering component is a filter membrane structure, and the filtering precision of the first filtering component is 20nm or 40nm or 100nm or 500nm.

[0008] Furthermore, the silicon carbide tubular membrane comprises a porous support layer for liquid circulation, a transition layer for intercepting silicon powder, and a separation layer for recovering cutting waste liquid. The porous support layer is formed with a plurality of regularly arranged first through holes, each of the first through holes is connected to and wrapped by the transition layer, and the separation layer is connected to and wraps outside the transition layer.

[0009] Furthermore, the second filtering component is a centrifugal separation mechanism. The centrifugal separation mechanism comprises a rotating drum and a filter screen for filtering the primary cutting fluid. The drum is provided with a plurality of second through holes for discharging the secondary cutting fluid, and the filter screen is used to cover the second through holes.

[0010] Furthermore, the drum is formed into a barrel-shaped structure, the second through holes are annularly arranged on the side wall of the drum, and the filter screen is arranged on the side wall of the drum.

[0011] Furthermore, the second filtering component is a diaphragm filter press mechanism. The diaphragm filter press mechanism comprises a substrate for support, a plurality of filter plates continuously and regularly arranged on the substrate for filtering liquid, a filter cloth arranged on the substrate for intercepting silicon powder, and a filter membrane attached to the filter plate for pressure filtration. The filter cloth is arranged between two filter plates.

[0012] Furthermore, the substrate is fixedly connected to the filter plates and the filter cloth, the filter membrane and the filter plates are fixedly connected, and the silicon powder particles in the primary cutting fluid filtered by the second filtering component adhere to the filter cloth to form a filter cake.

[0013] Furthermore, the first filtering device comprises a first feed inlet, a first discharge outlet, a fourth feed inlet and a fourth discharge outlet. The sludge tank comprises a second feed inlet and a second discharge outlet. The second filtering device comprises a third feed inlet and a third discharge outlet. The purified liquid collection tank comprises a fifth feed inlet and a fifth discharge outlet. The first feed inlet is used for collecting the cutting waste liquid discharged from the external wire sawing production line. The first discharge outlet is connected to the second feed inlet, the second discharge outlet is connected to the third feed inlet, the third discharge outlet is connected to the fourth feed inlet, the fourth discharge outlet is connected to the fifth feed inlet, and the fifth discharge outlet is used for conveying the cutting purified liquid to the wire sawing production line. The second filtering device further comprises a sixth discharge outlet for discharging silicon wafer particles.

[0014] Advantages of the present utility model: The silicon carbide tubular membrane of the first filtering device performs dead-end rapid filtration to obtain cut clean liquid, and the remaining cutting waste liquid enters the second filtering device for filtration. The silicon powder particles of the diaphragm filter press mechanism adhere to the filter cloth to form a filter cake. The filter membrane presses the filter cake under the action of high-pressure gas to obtain silicon powder particles with a lower water content. The drum of the centrifugal separation mechanism rotates to separate solids from liquids, and the filter net arranged on the side wall of the drum intercepts the silicon powder particles; through the rapid dead-end filtration of the silicon carbide tubular membrane and the physical filtration of the diaphragm filter press mechanism or the centrifugal separation mechanism, the cutting waste liquid can be recycled completely and efficiently. Description of the Drawings

[0015] Figure 1 It is a connection schematic diagram of a regeneration and reuse system for a diamond wire cutting fluid of the present utility model;

[0016] Figure 2 It is a process schematic diagram of a regeneration and reuse system for a diamond wire cutting fluid of the present utility model;

[0017] Figure 3 It is a structural schematic diagram of the first filtering component of the present utility model;

[0018] Figure 4 It is a structural schematic diagram of the first filtering component being a centrifugal separation mechanism of the present utility model;

[0019] Figure 5 It is a structural schematic diagram of the second filtering component being in an unfiltered state of the diaphragm filter press mechanism of the present utility model;

[0020] Figure 6 It is a structural schematic diagram of the second filtering component being in a filtered state of the diaphragm filter press mechanism of the present utility model.

[0021] Reference numerals include: 1. First filtering device; 11. First filtering component; 110. Silicon carbide tubular membrane; 1101. Porous support layer; 11011. First through hole; 1102. Transition layer; 1103. Separation layer; 12. First feed port; 13. First discharge port; 14. Fourth feed port; 15. Fourth discharge port; 2. Sludge tank; 21. Second feed port; 22. Second discharge port; 3. Second filtering device; 31. Second filtering component; 3101. Centrifugal separation mechanism; 31011. Drum; 31012. Filter net; 31013. Second through hole; 3102. Diaphragm filter press mechanism; 31021. Substrate; 31022. Filter plate; 31023. Filter cloth; 31024. Filter membrane; 31025. Filter cake; 32. Third feed port; 33. Third discharge port; 34. Sixth discharge port; 4. Clean liquid collection tank; 41. Fifth feed port; 42. Fifth discharge port. Detailed Embodiments

[0022] For the convenience of understanding by those skilled in the art, the following will further explain the present utility model in conjunction with embodiments and the appended Figures 1 to 6 drawings. The content mentioned in the implementation manners does not limit the present utility model.

[0023] A diamond wire cutting fluid regeneration and reuse system includes a first filtering device 1 for collecting cutting waste liquid discharged from an external diamond wire cutting production line, a sludge tank 2 communicated with the first filtering device 1, a second filtering device 3 communicated with the sludge tank 2, and a clean liquid collection tank 4 for supplying cutting clean liquid to the diamond wire cutting production line. The cutting clean liquid filtered by the first filtering device 1 is conveyed to the clean liquid collection tank 4. The first filtering device 1 includes a first filtering component 11 for filtering the cutting waste liquid to obtain cutting clean liquid. The second filtering device 3 includes a second filtering component 31 for filtering the primary cutting liquid output from the sludge tank 2. The filtering parameters of the first filtering component 11 are different from those of the second filtering component 31.

[0024] In actual use, the first filtering device 1 performs dead-end rapid filtration to quickly filter and separate the cutting waste liquid of the diamond wire cutting production line. The separated clean liquid enters the clean liquid collection tank 4. The primary cutting liquid enters the second filtering device 3 through the sludge tank 2. The second filtering device 3 completely filters the silicon powder particles, and the remaining secondary cutting liquid enters the first filtering device 1.

[0025] Specifically, the second filtering device 3 is communicated with the first filtering device 1, and the cutting clean liquid filtered by the second filtering device 3 is input into the first filtering device 1 for filtering.

[0026] Specifically, the first filtering component 11 is a filter membrane structure, and the filtering accuracy of the first filtering component 11 is 20nm, 40nm, 100nm or 500nm.

[0027] In actual use, the vast majority of the diameters of silicon powder are distributed above 100nm. According to the actual use situation, silicon carbide tubular membranes 110 with different filtering accuracies can be selected.

[0028] Specifically, the silicon carbide tubular membrane 110 includes a porous support layer 1101 for liquid circulation, a transition layer 1102 for intercepting silicon powder, and a separation layer 1103 for recovering cutting waste liquid. The porous support layer 1101 is formed with a plurality of regularly arranged first through holes 11011. Each first through hole 11011 is connected to and wrapped by the transition layer 1102. The separation layer 1103 is connected to the transition layer 1102 and wrapped outside the transition layer 1102.

[0029] In actual use, the first filtering device 1 filters in a dead-end rapid filtration manner. The cutting waste liquid from the wire sawing production line flows into the first filtering device 1. The cutting waste liquid flows into the porous support layer 1101 to form a fluid pressure. Most of the silicon powder in the cutting waste liquid is adsorbed in the transition layer 1102. The filtered clean liquid separated by the separation layer 1103 enters the clean liquid collection tank 4, and the separated primary cutting liquid enters the sludge tank 2 through the porous support layer 1101.

[0030] Specifically, the second filtering component 31 is a centrifugal separation mechanism 3101. The centrifugal separation mechanism 3101 includes a rotating drum 31011 and a filter screen 31012 for filtering the primary cutting liquid. The drum 31011 is provided with a plurality of second through holes 31013 for discharging the secondary cutting liquid, and the filter screen 31012 is used to cover the second through holes 31013.

[0031] Specifically, the drum 31011 is formed in a barrel-shaped structure. The second through holes 31013 are arranged in a ring on the side wall of the drum 31011, and the filter screen 31012 is arranged on the side wall of the drum 31011.

[0032] In actual use, the drum 31011 rotates, and solid-liquid substances of different masses are separated under the action of centrifugal force. The filter screen 31012 intercepts silicon powder particles, and the second through holes 31013 are used to discharge the separated secondary cutting liquid.

[0033] Specifically, the second filtering component 31 is a diaphragm pressure filtration mechanism 3102. The second filtering component 31 includes a substrate 31021 for support, a plurality of filter plates 31022 continuously and regularly arranged on the substrate 31021 for filtering liquid, a filter cloth 31023 arranged on the substrate 31021 for intercepting silicon powder, and a filter membrane 31024 attached to the filter plate 31022 for pressure filtration. The filter cloth 31023 is arranged between two filter plates 31022.

[0034] In actual use, the primary cutting liquid input from the sludge tank 2 enters the second filtering device 3. The filter plate 31022 is used for the primary cutting liquid to flow through. The silicon powder particles in the primary cutting liquid are adsorbed on the filter cloth 31023 to form a filter cake 31025. The filter membrane 31024 expands under the action of high-pressure gas to compress the filter cake 31025, and the moisture content of the silicon powder particles in the filter cake 31025 is further reduced. Subsequently, the filter cake 31025 is discharged, and the filtered secondary cutting liquid flows into the first filtering device 1.

[0035] Specifically, the substrate 31021 is fixedly connected to the filter plate 31022 and the filter cloth 31023, and the filter membrane 31024 is fixedly connected to the filter plate 31022. The silicon powder particles in the primary cutting liquid filtered by the second filtering component 31 adhere to the filter cloth 31023 to form a filter cake 31025.

[0036] Specifically, the first filtering device 1 includes a first feed inlet 12, a first discharge outlet 13, a fourth feed inlet 14, and a fourth discharge outlet 15. The sludge tank 2 includes a second feed inlet 21 and a second discharge outlet 22. The second filtering device 3 includes a third feed inlet 32 and a third discharge outlet 33. The purified liquid collection tank 4 includes a fifth feed inlet 41 and a fifth discharge outlet. The first feed inlet 12 is used to collect the cutting waste liquid discharged from the external wire sawing production line. The first discharge outlet 13 is connected to the second feed inlet 21. The second discharge outlet 22 is connected to the third feed inlet 32. The third discharge outlet 33 is connected to the fourth feed inlet 14. The fourth discharge outlet 15 is connected to the fifth feed inlet 41. The fifth discharge outlet is used to convey the filtered cutting purified liquid to the wire sawing production line. The second filtering device 3 further includes a sixth discharge outlet 34 for discharging silicon wafer particles.

[0037] During actual use, the first discharge outlet 13 is used to convey the cutting waste liquid to the first filtering device 1. The first discharge outlet 13 and the second feed inlet 21 are used to convey the cutting waste liquid with a lower silicon content to the sludge tank 2. The second discharge outlet 22 and the third feed inlet 32 are used to convey the cutting waste liquid with a lower silicon content to the second filtering device 3. The third discharge outlet 33 and the fourth feed inlet 14 are used to convey the cutting waste liquid with an even lower silicon content to the first filtering device 1. The fourth discharge outlet 15 and the fifth feed inlet 41 are used to convey the purified liquid to the purified liquid collection tank 4. The fifth discharge outlet is used to convey the filtered cutting purified liquid to the wire sawing production line. The sixth discharge outlet 34 is used to discharge silicon wafer particles.

[0038] In actual use, the silicon carbide tubular membrane 110 itself has the ability of cross-flow filtration. When the cutting waste liquid of the wire sawing production line enters the first filtering device 1 through the first feed port 12, dead-end filtration is carried out on it, which can accelerate the filtration and separation of the cutting waste liquid to obtain the cut clean liquid. The cut clean liquid flows into the clean liquid collection tank 4 through the fourth discharge port 15 and the fifth feed port 41; dead-end filtration will cause an increase in the accumulation of particles on the silicon carbide tubular membrane 110, thereby affecting the filtration effect. It is necessary to blow back the silicon carbide tubular membrane 110 of the first filtering device 1 regularly to discharge the silicon wafer particles in the silicon carbide tubular membrane 110, generating a primary cutting liquid with a relatively high content of silicon wafer particles and a relatively small amount of cutting waste liquid; the primary cutting liquid enters the second filtering device 3 through the sludge tank 2. The second filtering component 31 of the second filtering device 3 is a diaphragm pressure filtration mechanism 3102 or a centrifugal separation mechanism 3101; when the second filtering component 31 is the diaphragm pressure filtration mechanism 3102, the primary cutting liquid is initially separated through the filter plate 31022 and the filter cloth 31023, and a filter cake 31025 formed by the accumulation of solid particles is formed on the filter cloth 31023. The filter membrane 31024 provided on the filter plate 31022 expands under the injection of high-pressure air to squeeze the filter cake 31025, and the vast majority of the water in the filter cake 31025 is pressed out. The silicon wafer particles with a low moisture content formed are discharged through the sixth discharge port 34, and the secondary cutting liquid obtained by pressure filtration enters the first filtering device 1 through the third discharge port 33 and the fourth feed port 14 to continue dead-end filtration; when the second filtering component 31 is the centrifugal separation mechanism 3101, the drum 31011 rotates, and solid-liquid separation is carried out at different rotation speeds. The silicon powder particles are intercepted on the filter mesh 31012, and the remaining secondary cutting liquid enters the first filtering device 1 through the third discharge port 33 and the fourth feed port 14 to continue dead-end filtration, and the silicon wafer particles with a low moisture content formed are discharged through the sixth discharge port 34; through the rapid dead-end filtration of the silicon carbide tubular membrane 110 and the physical filtration of the diaphragm pressure filtration mechanism 3102 or the centrifugal separation mechanism 3101, the cutting waste liquid can be recycled completely and efficiently.

[0039] The above content is only the preferred embodiment of the present invention. For those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. The content of this specification should not be construed as a limitation to the present invention.

Claims

1. A diamond wire cutting fluid regeneration and reuse system, characterized in that: It includes a first filtering device (1) for collecting the cutting waste liquid discharged from the external diamond wire cutting production line, a sludge tank (2) communicated with the first filtering device (1), a second filtering device (3) communicated with the sludge tank (2), and a clean liquid collection tank (4) for supplying clean cutting liquid to the diamond wire cutting production line. The clean cutting liquid filtered by the first filtering device (1) is transported to the clean liquid collection tank (4); the first filtering device (1) includes a first filtering component (11) for filtering the cutting waste liquid to obtain clean cutting liquid, the second filtering device (3) includes a second filtering component (31) for filtering the primary cutting liquid output from the sludge tank (2), and the filtering parameters of the first filtering component (11) are different from those of the second filtering component (31).

2. The diamond wire cutting fluid regeneration and reuse system according to claim 1, wherein: The second filtering device (3) is communicated with the first filtering device (1), and the clean cutting liquid filtered by the second filtering device (3) is input into the first filtering device (1) for filtering.

3. The diamond wire cutting fluid regeneration and reuse system according to claim 1, wherein: The first filtering component (11) is a filter membrane structure, and the filtering precision of the first filtering component (11) is 20nm, 40nm, 100nm or 500nm.

4. The diamond wire cutting fluid regeneration and reuse system according to claim 3, wherein: The first filtering component (11) is a silicon carbide tubular membrane (110). The silicon carbide tubular membrane (110) includes a porous support layer (1101) for liquid circulation, a transition layer (1102) for intercepting silicon powder, and a separation layer (1103) for recovering the cutting waste liquid. The porous support layer (1101) is formed with a plurality of regularly arranged first through holes (11011), each first through hole (11011) is connected to the transition layer (1102) and wrapped by the transition layer (1102), and the separation layer (1103) is connected to the transition layer (1102) and wrapped outside the transition layer (1102).

5. The regenerative reuse system for a diamond wire cutting fluid according to claim 1, characterized in that: The second filtering component (31) is a centrifugal separation mechanism (3101). The centrifugal separation mechanism (3101) includes a rotating drum (31011) and a filter screen (31012) for filtering the primary cutting liquid. The drum (31011) is provided with a plurality of second through holes (31013) for discharging the secondary cutting liquid, and the filter screen (31012) is used to cover the second through holes (31013).

6. The regenerative reuse system for diamond wire cutting fluid according to claim 5, wherein: The drum (31011) is formed into a barrel-shaped structure, and a plurality of second through holes (31013) are arranged in a circular array on the side wall of the drum (31011), and the filter screen (31012) is arranged on the side wall of the drum (31011).

7. A diamond wire cutting fluid regeneration and reuse system according to claim 1, characterized in that: The second filtering component (31) is a diaphragm filter press mechanism (3102). The diaphragm filter press mechanism (3102) includes a substrate (31021) for support, a plurality of filter plates (31022) continuously and regularly arranged on the substrate (31021) for filtering the primary cutting liquid, a filter cloth (31023) arranged on the substrate (31021) for intercepting silicon powder, and a filter membrane (31024) attached to the filter plate (31022) for pressure filtration. The filter cloth (31023) is arranged between two filter plates (31022).

8. A diamond wire cutting fluid regeneration and reuse system according to claim 7, characterized in that: The substrate (31021) is fixedly connected to the filter plate (31022) and the filter cloth (31023). The filter membrane (31024) is fixedly connected to the filter plate (31022). The second filtration assembly (31) filters the silicon powder particles in the primary cutting fluid, and the filter cake (31025) is formed by attachment to the filter cloth (31023).

9. The regenerative reuse system for diamond wire cutting fluid according to claim 1, wherein: The first filtration device (1) includes a first feed inlet (12), a first discharge outlet (13), a fourth feed inlet (14), and a fourth discharge outlet (15). The sludge tank (2) includes a second feed inlet (21) and a second discharge outlet (22). The second filtration device (3) includes a third feed inlet (32) and a third discharge outlet (33). The purified liquid collection tank (4) includes a fifth feed inlet (41) and a fifth discharge outlet (42). The first feed inlet (12) is used to collect the cutting waste liquid discharged from the external wire sawing production line. The first discharge outlet (13) is connected to the second feed inlet (21). The second discharge outlet (22) is connected to the third feed inlet (32). The third discharge outlet (33) is connected to the fourth feed inlet (14). The fourth discharge outlet (15) is connected to the fifth feed inlet (41). The fifth discharge outlet (42) is used to convey the cutting purified liquid to the wire sawing production line. The second filtration device (3) further includes a sixth discharge outlet (34) for discharging silicon wafer particles.

Images