Device and method for removing light impurities from silicon crystal foams

Abstract

The invention provides a silicon crystal foam material light impurity removing device which comprises a vibration feeding device and an overflow cleaning device, silicon crystal foam materials are placed in the overflow cleaning device through the vibration feeding device, and the silicon crystal foam materials are subjected to light impurity removing through the overflow cleaning device. The invention further provides a method for removing the light impurities from the silicon crystal foam materials. The method comprises the steps of vibration feeding and overflow cleaning. The device has the beneficial effects that automatic light impurity removal of silicon crystal foam materials is achieved, the impurity removal efficiency is improved, the impurity removal effect and the product quality are guaranteed, the structure is simple, and operation is convenient and fast.

Description

Technical Field

[0001] The invention belongs to the technical field of silicon material impurity removal, and in particular relates to a device and method for removing light impurities from silicon crystal foam material. Background Art

[0002] In the solar photovoltaic and semiconductor material manufacturing industries, silicon crystals as raw materials are prone to produce 1-3 mm silicon crystal foam during the classification and turnover process. When silicon crystal foam is used as a raw material, it is necessary to remove impurities. In the prior art, manual cleaning is often used to remove light impurities, but light impurities in silicon crystal foam are not easy to remove, the impurity removal effect is not ideal, and the impurity removal efficiency is low, which affects product quality. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a device and method for removing light impurities from silicon crystal foam, which effectively solves the problems of low efficiency of removing light impurities from silicon crystal foam and unsatisfactory impurity removal effect, and overcomes the shortcomings of the prior art.

[0004] The technical solution adopted by the present invention is: a device for removing light impurities from silicon crystal foam, comprising: a vibration feeding device and an overflow cleaning device, the vibration feeding device places the silicon crystal foam in the overflow cleaning device, and the overflow cleaning device removes light impurities from the silicon crystal foam.

[0005] Furthermore, the overflow cleaning device includes an overflow trough and a conveyor belt, one end of the conveyor belt is immersed in the overflow trough for receiving the silicon crystal foam material, and the other end is arranged outside the overflow trough to transport the silicon crystal foam material after light impurities are removed to the outside of the overflow trough.

[0006] Furthermore, the conveyor belt is arranged at an angle, with one end arranged outside the overflow trough being higher than the end immersed in the overflow trough, so that the conveyor belt portion located in the overflow trough is arranged above the liquid surface of the overflow trough.

[0007] Furthermore, a first spray head and a second spray head are provided above the conveyor belt above the liquid level in the overflow tank, and are arranged in sequence along the conveying direction of the conveyor belt.

[0008] Furthermore, a filter tank is provided on one side of the overflow tank for filtering light impurities to form circulating water to supply water to the first sprinkler head.

[0009] Furthermore, a circulating water tank is provided on one side of the filter tank away from the overflow tank, and the circulating water tank is connected to the bottom of the filter tank and is used to store the circulating water to supply water to the first sprinkler head.

[0010] Furthermore, a feed nozzle is provided below one end of the conveyor belt outside the overflow trough, which is used to separate the silicon crystal foam material after impurities are removed from the conveyor belt.

[0011] A method for removing light impurities from silicon crystal foam material, using the above-mentioned silicon crystal foam material light impurity removal device, the steps comprising:

[0012] Vibration feeding, using the vibration feeding device to feed the silicon crystal foam material;

[0013] Overflow cleaning: using the overflow cleaning device to remove light impurities from the silicon crystal foam material.

[0014] Furthermore, the overflow cleaning includes overflow impurity removal, and the overflow cleaning device includes an overflow trough and a conveyor belt, one end of the conveyor belt is immersed in the overflow trough, and the other end is arranged outside the overflow trough, and the end arranged outside the overflow trough is higher than the end immersed in the overflow trough, so that the conveyor belt part located in the overflow trough is arranged above the liquid surface of the overflow trough, and the vibrating feeding device places the silicon crystal foam material on the end of the conveyor belt immersed in the overflow trough for impurity removal, and the conveyor belt moves the silicon crystal foam material after impurity removal out of the liquid surface of the overflow trough.

[0015] Furthermore, the overflow cleaning also includes spray flushing. A first spray head and a second spray head are sequentially arranged above the conveyor belt above the liquid level in the overflow tank along the conveying direction of the conveyor belt. After the silicon crystal foam material completes the overflow impurity removal step, it moves out of the liquid level of the overflow tank. The first spray head and the second spray head sequentially flush the silicon crystal foam material.

[0016] The advantages and positive effects of the present invention are as follows: by adopting the above technical scheme, the light impurities of silicon crystal foam material can be automatically removed, the impurity removal efficiency is improved, the impurity removal effect and product quality are guaranteed, the structure is simple, and the operation is convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The present invention is a schematic diagram of the overall structure of a device for removing light impurities from silicon crystal foam material according to an embodiment of the present invention.

[0018] Figure 2 The present invention is a schematic diagram of the working process of a device for removing light impurities from silicon crystal foam material according to an embodiment of the present invention.

[0019] In the figure:

[0020] 1. Overflow tank 2. Conveyor belt 3. Liquid level

[0021] 4. First spray head 5. Second spray head 6. Spacer

[0022] 7. Filter tank 8. Filter screen 9. Circulating water tank

[0023] 10. Feeding nozzle 11. Vibration motor 12. Feeding trough

[0024] 13. Silicon crystal foam material DETAILED DESCRIPTION

[0025] The embodiment of the present invention provides a device and method for removing light impurities from silicon crystal foam material. The embodiment of the present invention is described below in conjunction with the accompanying drawings.

[0026] In the description of the embodiments of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "top", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "set" and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0027] like Figure 1 As shown, a device for removing light impurities from silicon crystal foam material according to an embodiment of the present invention includes a vibration feeding device and an overflow cleaning device. The vibration feeding device places silicon crystal foam material 13 in the overflow cleaning device, and the overflow cleaning device removes light impurities from the silicon crystal foam material 13. The vibration feeding device can evenly spread the silicon crystal foam material 13 in the overflow cleaning device, and the silicon crystal foam material 13 enters the overflow cleaning device for cleaning. The light impurities in the silicon crystal foam material 13 float on the liquid surface 3 due to their low density, and overflow out of the overflow cleaning device with the water flow, thereby achieving the purpose of impurity removal.

[0028] The overflow cleaning device includes an overflow trough 1 and a conveyor belt 2, one end of the conveyor belt 2 is immersed in the overflow trough 1, and is used to receive the silicon crystal foam material 13, and the other end extends out of the overflow trough 1, and is arranged outside the overflow trough 1, and the silicon crystal foam material 13 with light impurities removed is moved out of the overflow trough 1. The vibrating feeding device evenly spreads the silicon crystal foam material 13 on one end of the conveyor belt 2 immersed in the overflow trough 1, and the light impurities float on the water surface due to their low density and overflow with the water flow, and the conveyor belt 2 transfers the silicon crystal foam material 13 after impurities are removed to the outside of the overflow trough 1. The laying thickness of the silicon crystal foam material 13 is not easy to be too large, which affects the overflow of light impurities. The preferred laying thickness is 1-2mm. The conveyor belt 2 is provided with protrusions or baffles on both sides, which are not shown in the figure, to prevent the silicon crystal foam material 13 from falling into the overflow trough 1. The height of the protrusions or baffles can be determined according to the laying thickness, as long as it is greater than the laying thickness.

[0029] The conveyor belt 2 is tilted, and one end outside the overflow tank 1 is higher than the end immersed in the overflow tank 1, so that the conveyor belt 2 part located in the overflow tank 1 is located above the liquid level 3 of the overflow tank 1, that is, the end of the conveyor belt 2 close to the vibrating feeding device is located below the liquid level 3, and the end away from the vibrating feeding device is tilted upward, so that the silicon crystal foam material 13 after overflow impurity removal gradually emerges from the water surface until it is transmitted to the outside of the overflow tank 1. A part of the conveyor belt 2 located in the overflow tank 1 is below the liquid level 3, and a part is above the liquid level 3. In order to avoid the silicon crystal foam material 13 after overflow impurity removal from being contaminated, the length of the conveyor belt 2 below the liquid level 3 should not be too long, preferably not more than 1 meter, that is, the vibrating feeding device places the silicon crystal foam material 13 on the conveyor belt 2 for overflow impurity removal, and then it is transmitted to the liquid level 3 by the conveyor belt 2. The inclination angle of the conveyor belt 2 is not too large, which causes the silicon crystal foam material 13 to be unable to be spread on the conveyor belt 2, affecting the impurity removal effect. The inclination angle of the conveyor belt 2 is preferably 3-5°.

[0030] In order to further ensure the impurity removal effect, a spray device can be arranged above the conveyor belt 2 above the liquid level 3 of the overflow tank 1 to spray and remove impurities from the silicon crystal foam material 13 after the overflow impurity removal, and the silicon crystal foam material 13 is rinsed with the spray device. The spray device includes a first spray head 4 and a second spray head 5, which are arranged in sequence along the transmission direction of the conveyor belt 2. The water sprayed by the spray device further breaks up the silicon crystal foam material 13, flushes out the light impurities wrapped in the material, enters the overflow tank and overflows with the water flow. By setting a two-stage spray head and rinsing multiple times, the cleanliness of the silicon crystal foam material 13 is further ensured.

[0031] Since the conveyor belt 2 is arranged at an angle, in order to prevent the silicon crystal foam material 13 from sliding down and causing accumulation, which affects the impurity removal effect, a spacer bar 6 is arranged on the conveyor belt 2, and the spacer bar 6 is evenly arranged along the conveyor belt 2. The spacing distance of the spacer bar 6 is 200-300mm, and the height of the spacer bar 6 can be set according to the thickness of the silicon crystal foam material 13, as long as it is greater than the laying thickness of the silicon crystal foam material 13, preferably 3-10mm.

[0032] A filter tank 7 is provided on one side of the overflow tank 1. The water in the overflow tank 1 overflows into the filter tank 7 for filtration. A filter screen 8 is provided on the top of the filter tank 7 to filter the light impurities in the water. Circulating water is formed at the bottom of the filter screen 8 and can be recycled. The installation height of the filter screen 8 should be lower than the liquid level 3 of the overflow tank 1. When the circulating water is in use, it should be ensured that the liquid level 3 of the circulating water is always lower than the height of the filter screen 8. The filter screen 8 can be a nylon net with a pore size of 300 or finer.

[0033] A circulating water tank 9 is provided on the side of the filter tank 7 away from the overflow tank 1. The circulating water tank 9 is connected to the bottom of the filter tank 7 and is used to store circulating water. The circulating water tank 9 is connected to the first spray head 4, that is, the first spray head 4 uses circulating water for spraying, and the second spray head 5 uses clean water for spraying, which not only ensures the spraying effect but also saves water resources.

[0034] In order to prevent the silicon crystal foam material 13 after light impurities are removed from adhering to the conveyor belt 2 and being unable to be unloaded, a material unloading nozzle 10 is provided below one end of the conveyor belt 2 outside the overflow tank 1, which is used to separate the silicon crystal foam material 13 after impurities are removed from the conveyor belt 2. The material unloading nozzle 10 is arranged on the outer wall of the overflow tank 1 obliquely upward, and separates the silicon crystal foam material 13 from the conveyor belt 2 by spraying water obliquely upward.

[0035] The vibrating feeding device is installed above the overflow cleaning device, and includes a vibration motor 11 and a feeding trough 12. The vibration motor 11 is arranged at the bottom of the feeding trough 12. In order to facilitate feeding, the feeding trough 12 is tilted, and one end close to the conveyor belt 2 is lower than the other end. The vibration motor 11 makes the feeding trough 12 vibrate, and the tilted feeding trough 12 spreads the silicon crystal foam material 13 on one end of the conveyor belt 2 immersed in the overflow trough 1.

[0036] Embodiment: A device for removing light impurities from silicon crystal foam material, such as Figure 1As shown, it includes an overflow trough 1, a conveyor belt 2, a first spray head 4, a second spray head 5, a filter trough 7, a circulating water trough 9, a feed spray head 10, a vibration motor 11 and a feed trough 12. The conveyor belt 2 is installed obliquely in the overflow trough 1, with one end immersed in the overflow trough 1 and the other end extending out of the overflow trough 1. The end outside the overflow trough 1 is higher than the end immersed in the overflow trough 1, so that the part of the conveyor belt 2 located in the overflow trough 1 is arranged above the liquid level 3 of the overflow trough 1. Part of the conveyor belt 2 located in the overflow trough 1 is below the liquid level 3, and part is above the liquid level 3. The length of the conveyor belt 2 below the liquid level 3 is 500mm, and the inclination angle of the conveyor belt 2 is 3°. The first spray head 4 and the second spray head 5 are arranged in sequence along the conveying direction of the conveyor belt 2 above the conveyor belt 2 located above the liquid level 3 of the overflow trough 1. Spacer strips 6 with an interval of 250mm are evenly arranged on the conveyor belt 2. Baffles are arranged on both sides of the conveyor belt 2, which are not shown in the figure. The height of the baffle and the spacer bar 6 are both higher than the laying thickness of the silicon crystal foam material 13, which is 3 mm. A filter tank 7 is set on one side of the overflow tank 1, and a 300-mesh nylon filter screen 8 is installed above the filter tank 7. A circulating water tank 9 is provided on the side of the filter tank 7 away from the overflow tank 1, which is connected to the bottom of the filter tank 7 and is used to supply water to the first sprinkler head 4. The discharge nozzle 10 is arranged below the end of the conveyor belt 2 arranged outside the overflow tank 1. The vibration motor 11 is arranged at the bottom of the upper feeding trough 12, and the upper feeding trough 12 is arranged at one end of the conveyor belt 2 immersed in the overflow tank 1. The upper feeding trough 12 is inclined, and the end close to the conveyor belt 2 is lower than the other end. The inclined upper feeding trough 12 spreads the silicon crystal foam material 13 flat on the end of the conveyor belt 2 immersed in the overflow tank 1.

[0037] A method for removing light impurities from silicon crystal foam material, using a silicon crystal foam material 13 light impurity removal device as described above, such as Figure 2 As shown, the specific steps are: vibration loading, overflow impurity removal, spray impurity flushing and water spray unloading.

[0038] The vibration motor 11 drives the downwardly inclined feeding trough 12 to vibrate, and the feeding trough 12 evenly spreads the silicon crystal foam material 13 in the overflow cleaning device. The overflow cleaning device performs overflow cleaning on the silicon crystal foam material 13. Light impurities float on the liquid surface 3 due to their low density and overflow the overflow cleaning device with the water flow.

[0039] Overflow cleaning includes overflow impurity removal. The loading trough 12 evenly lays the silicon crystal foam material 13 on one end of the conveyor belt 2 immersed in the overflow trough 1, with a laying thickness of 1-2mm. After the silicon crystal foam material 13 enters the overflow trough 1, light impurities float on the liquid surface 3 and overflow with the water flow. The silicon crystal foam material 13 after impurity removal is moved out of the liquid surface 3 by the conveyor belt 2. The conveying speed of the conveyor belt 2 is 0.2-1m / s. The water overflowing from the overflow trough 1 enters the filter trough 7, is filtered through the filter screen 8, forms circulating water, and is stored in the circulating water tank 9.

[0040] Overflow cleaning also includes spraying and flushing. After the conveyor belt 2 moves the silicon crystal foam material 13 after overflow impurity removal out of the liquid surface 3, the first spray head 4 uses the circulating water of the circulating water tank 9 to perform the first flushing and impurity removal on the silicon crystal foam material 13 on the conveyor belt 2, and the second spray head 5 uses clean water to perform the second flushing and impurity removal. The silicon crystal foam material 13 is dispersed by the first spray head 4 and the second spray head 5, which is more conducive to flushing out the light impurities therein, and overflowing into the overflow tank 1 with the flushing water. During the flushing process, the spacer 6 set on the conveyor belt 2 can prevent the silicon crystal foam material 13 from sliding down to ensure the flushing effect.

[0041] The silicon crystal foam material 13 after overflow cleaning is conveyed to the outside of the overflow tank 1 by the conveyor belt 2. In order to facilitate unloading, a unloading nozzle 10 is used to spray water obliquely upward to separate the silicon crystal foam material 13 after impurities are removed from the conveyor belt 2.

[0042] The advantages and positive effects of the present invention are:

[0043] 1. It realizes the automatic removal of light impurities from silicon crystal foam, saves labor, improves the efficiency of impurity removal, has a simple structure and is easy to operate.

[0044] 2. Multiple impurities removal is carried out through overflow impurity removal and spray flushing to ensure the impurity removal effect and product quality.

[0045] 3. The first sprinkler head uses circulating water for flushing, saving water resources.

[0046] 4. In the prior art, silicon crystal foam materials that are not completely impurity-removed are mostly used for purification or direct sale and cannot be used for production. Silicon crystal foam materials that are impurity-removed by adopting this technical solution can be used for the production of single crystals, reducing the production cost of single crystals.

[0047] The embodiments of the present invention are described in detail above, but the contents described are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A device for removing light impurities from silicon crystal foam, characterized in that: include: A vibration feeding device and an overflow cleaning device, wherein the vibration feeding device places silicon crystal foam material in the overflow cleaning device, and the overflow cleaning device removes light impurities from the silicon crystal foam material.

2. A device for removing light impurities from silicon crystal foam material according to claim 1, characterized in that: The overflow cleaning device includes an overflow trough and a conveyor belt. One end of the conveyor belt is immersed in the overflow trough for receiving the silicon crystal foam material, and the other end is arranged outside the overflow trough to transport the silicon crystal foam material after light impurities are removed to the outside of the overflow trough.

3. A device for removing light impurities from silicon crystal foam material according to claim 2, characterized in that: The conveyor belt is arranged obliquely, and one end arranged outside the overflow trough is higher than the end immersed in the overflow trough, so that the part of the conveyor belt located in the overflow trough is arranged above the liquid surface of the overflow trough.

4. A device for removing light impurities from silicon crystal foam material according to claim 3, characterized in that: A first spray head and a second spray head are arranged above the conveyor belt above the liquid level in the overflow tank, and are arranged in sequence along the conveying direction of the conveyor belt.

5. A device for removing light impurities from silicon crystal foam material according to claim 4, characterized in that: A filter tank is provided on one side of the overflow tank for filtering light impurities to form circulating water to supply water to the first spray head.

6. A device for removing light impurities from silicon crystal foam material according to claim 5, characterized in that: A circulating water tank is provided on one side of the filter tank away from the overflow tank. The circulating water tank is connected to the bottom of the filter tank and is used to store the circulating water to supply water to the first spray head.

7. A device for removing light impurities from silicon crystal foam material according to any one of claims 2 to 6, characterized in that: The conveyor belt is arranged at a lower end outside the overflow trough and is provided with a material discharge nozzle for separating the silicon crystal foam material after impurities are removed from the conveyor belt.

8. A method for removing light impurities from silicon crystal foam material, characterized in that: The device for removing light impurities from silicon crystal foam material as claimed in any one of claims 1 to 7 is used, and the steps include: Vibration feeding, using the vibration feeding device to feed the silicon crystal foam material; Overflow cleaning: using the overflow cleaning device to remove light impurities from the silicon crystal foam material.

9. The method for removing light impurities from silicon crystal foam material according to claim 8, characterized in that: The overflow cleaning includes overflow impurity removal. The overflow cleaning device includes an overflow trough and a conveyor belt. One end of the conveyor belt is immersed in the overflow trough, and the other end is arranged outside the overflow trough. The end arranged outside the overflow trough is higher than the end immersed in the overflow trough, so that the conveyor belt part located in the overflow trough is arranged above the liquid surface of the overflow trough. The vibrating feeding device places the silicon crystal foam material on the end of the conveyor belt immersed in the overflow trough for impurity removal, and the conveyor belt moves the silicon crystal foam material after impurity removal out of the liquid surface of the overflow trough.

10. The method for removing light impurities from silicon crystal foam material according to claim 9, characterized in that: The overflow cleaning also includes spray flushing. A first spray head and a second spray head are sequentially arranged above the conveyor belt above the liquid level in the overflow tank along the conveying direction of the conveyor belt. After the silicon crystal foam material completes the overflow impurity removal step, it moves out of the liquid level of the overflow tank. The first spray head and the second spray head sequentially flush the silicon crystal foam material.

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