A photovoltaic debris screening system and method of separating photovoltaic module glass sheets and silicon wafers

Abstract

The application discloses a photovoltaic fragment screening system and a method for separating photovoltaic component glass plates and silicon pieces, and the photovoltaic fragment screening system comprises a screen, a vibrating member, a material receiving tray and a control mechanism, the screen is used for screening photovoltaic fragments, the vibrating member is used for driving the screen to vibrate, the material receiving tray is used for receiving the screened photovoltaic fragments, and the control mechanism comprises a weighing device and a vibration control device, the vibration control device is connected with the vibrating member to control the vibration of the vibrating member, and the weighing device is electrically connected with the vibration control device to send weight information of silicon piece material on the screen to the vibration control device, and the vibration control device controls the vibration of the vibrating member according to the weight information of the silicon piece material. The photovoltaic fragment screening system provided by the application has the advantages of high screening efficiency, complete material separation and high material recovery rate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of photovoltaic recycling, and in particular to a photovoltaic fragment screening system and a method for separating photovoltaic component glass plates and silicon wafers. BACKGROUND

[0002] Photovoltaic power generation is an important direction of new energy development, but as the photovoltaic power generation industry develops rapidly, the production of waste photovoltaic components has increased rapidly. Developing efficient disassembly technology and resource recycling technology to achieve complete separation of photovoltaic component cells, glass, back plate, solder strip, etc. and recycling of crystalline silicon and various metal elements has become a research hotspot. The first step of recycling is to preliminarily separate the photovoltaic panel. The solder strip, electrode, and crystalline silicon in the structure of the photovoltaic panel can be regarded as a whole, and this whole is sandwiched in the tempered glass through the packaging layer, so it is difficult to separate. SUMMARY

[0003] The present application is based on the inventors' discovery and understanding of the fact and problem that glass and crystalline silicon are difficult to separate in photovoltaic recycling.

[0004] The present application aims to at least partially solve one of the technical problems in the related art. To this end, an embodiment of the present application proposes a photovoltaic fragment screening system, which has the advantages of high screening efficiency, complete material separation, and high material recovery rate.

[0005] The photovoltaic fragment screening system according to an embodiment of the present application includes a screen, a vibrating member, a material receiving tray, and a control mechanism. The screen is used to screen photovoltaic fragments. The screen is a single-direction screen. The spacing of the screen is adjusted according to the equivalent diameter and thickness of the photovoltaic fragments to complete the separation of glass and silicon wafers. The vibrating member is used to drive the screen to vibrate. The material receiving tray is used to receive the screened photovoltaic fragments. The control mechanism includes a weighing device and a vibration control device. The vibration control device is connected to the vibrating member to control the vibration of the vibrating member. The weighing device is electrically connected to the vibration control device to send the weight information of the silicon wafer material on the screen to the vibration control device. The vibration control device controls the vibration of the vibrating member according to the weight information of the silicon wafer material. The vibration control device includes a data processor. The weighing device records the weight of the material receiving tray within a preset time period. The data processor obtains the falling speed of the silicon wafer material according to the time and weight data. The vibration control device controls the vibration of the vibrating member according to the falling speed of the silicon wafer material.

[0006] The photovoltaic fragment screening system according to an embodiment of the present application has the advantages of high screening efficiency, complete material separation, and high material recovery rate.

[0007] In some embodiments, the screen has a mesh size of 0.2mm-1mm.

[0008] The method for separating the photovoltaic module glass plate and the silicon wafer according to the embodiment of the present application comprises the following steps:

[0009] Baking the photovoltaic plate in a preset temperature range;

[0010] Collecting the material fragments after baking;

[0011] Starting a screening system to screen the material fragments, and the screening system adopts a vibration mode with the maximum screening efficiency according to the falling speed of the silicon wafer;

[0012] The vibrator maintains the vibration mode with the maximum screening efficiency until the screening is completed.

[0013] In some embodiments, after the large-size broken pieces and long strip solder belts in the baked material fragments are picked out, the glass in the baked material fragments is broken into fragments with an equivalent diameter of 3-8mm, and the silicon wafer is broken into irregular thin pieces with a thickness of 0-0.2mm.

[0014] In some embodiments, the weight difference of the silicon wafer in a target time period is obtained by subtracting the weight of the silicon wafer in the adjacent time period from the weight of the silicon wafer in the target time period, and the falling speed of the silicon wafer is the ratio of the weight difference to the time period.

[0015] In some embodiments, the screen maintains the same vibration mode in several time periods, and all the vibration modes are traversed to obtain the vibration mode with the maximum falling speed of the silicon wafer and the screening mode with the highest screening efficiency.

[0016] In some embodiments, the glass on the screen is discharged to a glass receiving tray after reaching a target weight.

[0017] The method and the corresponding device principle of the present application are reliable, the execution process is simple, the separation of the tempered glass, the packaging layer and the silicon wafer layer is complete, and the method is an effective measure in the photovoltaic plate recycling process. The method of the present application utilizes high-temperature baking to decompose the packaging layer between the silicon wafer and the glass, so that the glass and the silicon wafer are completely separated, which facilitates screening and separation of the mixed fragments, further recycling of the two materials, and improvement of the material recycling rate. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a use state diagram of the photovoltaic fragment screening system according to the embodiment of the present application.

[0019] Figure 2 is a structure diagram of the screen of the photovoltaic fragment screening system according to the embodiment of the present application.

[0020] Reference numeral: 1, glass; 2, silicon wafer; 3, material receiving tray; 4, screen. DETAILED DESCRIPTION

[0021] Embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings. The embodiments described below by reference to the drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation of the present application.

[0022] According to the photovoltaic debris screening system of the embodiments of the present application, as shown in Figure 1 and Figure 2 The photovoltaic debris screening system comprises a screen 4 for screening photovoltaic debris, a vibrating member for driving the screen 4 to vibrate, a material receiving tray 3 for receiving the screened photovoltaic debris, and a control mechanism comprising a weighing device and a vibration control device, the vibration control device being connected to the vibrating member to control the vibration of the vibrating member, and the weighing device being electrically connected to the vibration control device to send the weight information of the silicon wafer 2 material on the screen 4 to the vibration control device, and the vibration control device controlling the vibration of the vibrating member according to the weight information of the silicon wafer 2 material. The screening system controls the vibration speed and vibration direction of the vibrating member through the control mechanism, the vibrating member drives the screen 4 to vibrate so that the glass 1 in the photovoltaic debris on the screen 4 stays above the screen 4, and the silicon wafer 2 falls through the gap of the screen 4 and lands on the material receiving tray 3, the control mechanism detects the weight information of the silicon wafer 2 material on the material receiving tray 3 through the weighing device to determine the screening effect of the screen 4, and adjusts the vibration speed and vibration direction of the vibrating member according to the screening effect, so that the screening system has the optimal screening efficiency and screening effect.

[0023] The photovoltaic debris screening system according to the embodiments of the present application has the advantages and technical effects of high screening efficiency, complete material separation, and high material recovery rate.

[0024] In some embodiments, the vibration control device comprises a data processor, the weighing device records the weight of the material receiving tray 3 within a preset time period, the data processor obtains the falling speed of the silicon wafer material according to the time and weight data, and the vibration control device controls the vibration of the vibrating member according to the falling speed of the silicon wafer material.

[0025] Specifically, the data processor can be a computer or other data processing device, the weighing device weighs the material receiving tray 3, the data processor collects the weight data and processes the data, and the vibration control device controls the vibration of the vibration member according to the result of the data processor. A time period can be one second or a shorter time interval such as 0.1 second, and the weight of the silicon wafer 2 on the material receiving tray 3 is recorded once in a time period. The dropping speed of the silicon wafer 2 material is the difference between the weight value of the next time period and the weight value of the previous time period divided by the time period. After switching the vibration mode, the dropping speed of the silicon wafer 2 material is compared to obtain the vibration mode with the best effect in the vibration mode to improve the screening efficiency.

[0026] In some embodiments, the screen 4 is a single direction screen 4.

[0027] Specifically, the conventional screen 4 is formed by the intersection of warp and weft lines, and the single direction screen 4 can facilitate the falling of the silicon wafer 2 and ensure the screening efficiency. Therefore, the vibration direction of the screen 4 can be within a range from parallel to the weaving direction of the screen 4 itself to perpendicular to the weaving direction of the screen 4 itself, and the vibration direction can also be clockwise or counterclockwise rotation to play a role in screening the silicon wafer 2.

[0028] In some embodiments, the size of the spacing of the screen 4 is adjusted according to the equivalent diameter and thickness of the photovoltaic fragments to separate the glass 1 and the silicon wafer 2.

[0029] Specifically, the size of the spacing of the screen 4 should be smaller than the equivalent diameter of the glass 1 in the photovoltaic fragments and larger than the thickness of the silicon wafer 2 to facilitate the separation of the glass 1 and the silicon wafer 2. If the spacing is increased, the screening efficiency will be accelerated and the screening quality will be reduced, and if the spacing is reduced, the screening efficiency will be reduced and the screening quality will be improved to avoid the falling of the glass 1. The size of the spacing of the screen 4 can be the most suitable size for the screening efficiency and the screening quality. The screening effect is most suitable when the size of the spacing of the screen 4 is 0.2 mm to 1 mm.

[0030] The photovoltaic module glass plate and silicon wafer separation method according to the embodiments of the present application includes the following steps:

[0031] Firing the photovoltaic plate in a preset temperature range; the preset temperature range is 450℃ to 700℃, and the photovoltaic plate with the outer frame removed is fired in this temperature range. High temperature completely decomposes the encapsulation layer between the silicon wafer 2 and the glass 1, so that the tempered glass 1 and the silicon wafer 2 are separated and there is no residual encapsulation layer.

[0032] Collecting the material fragments after firing; the photovoltaic plate after high-temperature firing will crack due to stress, the glass 1 will crack into fragments, and the silicon wafer 2 including crystalline silicon and the attached electrode layer, anti-reflection layer, etc. will break into irregular thin pieces.

[0033] The opening screening system screens the material fragments, and the screening system obtains the vibration mode with the maximum screening efficiency according to the falling speed of the silicon wafer 2.

[0034] The vibrator maintains the vibration mode with the maximum screening efficiency until the screening is completed. The screening system vibrates the silicon wafer 2 and the glass 1 in the vibration mode with the maximum screening efficiency, so as to separate the glass 1 and the silicon wafer 2.

[0035] In some embodiments, after the large-size fragments and the long strip solder belt in the calcined material fragments are picked out, the glass 1 in the calcined material fragments is broken into fragments with an equivalent diameter of 3-8 mm, and the silicon wafer 2 is broken into irregular thin pieces with a thickness of 0-0.2 mm.

[0036] Specifically, the glass 1 and the silicon wafer 2 are uniformly processed and broken into small fragments of a target specification, so as to facilitate subsequent screening processing and improve the screening efficiency. The state of the broken glass and silicon wafer is affected by the calcination temperature, the type of glass, and the like. The calcination temperature and the calcination time can be adjusted according to the desired fragment size and the type of raw material. The pre-picking of the large-size fragments and the solder belt in the fragments can reduce the processing steps and shorten the breaking time.

[0037] Optionally, a plurality of size specifications of screen meshes are added to perform multiple pre-screening on the calcined fragments, so as to obtain fragments with a target particle size range. The large-size fragments that do not pass through are subjected to re-breaking processing. The re-breaking can be mechanical breaking or manual breaking.

[0038] In some embodiments, the weight value of the silicon wafer 2 in a target time period is subtracted from the weight of the silicon wafer 2 in the adjacent time period to obtain a difference in weight value, and the falling speed of the silicon wafer 2 is the ratio of the difference in weight value to the time period.

[0039] Specifically, the integral of the obtained weight data with respect to time can obtain a curve, and the slope of the curve is the falling speed of the silicon wafer 2. The number of time periods selected for calculating the falling speed of the silicon wafer 2 can be the total length of any number of time periods.

[0040] In some embodiments, the screen mesh 4 maintains the same vibration mode in a plurality of time periods, and all vibration modes are traversed to obtain the vibration mode with the maximum falling speed of the silicon wafer 2, so as to obtain the screening mode with the highest screening efficiency.

[0041] Specifically, the number of time periods selected for calculating the falling speed of the silicon wafer 2 can be the total length of any number of time periods. For example, 1 time period or 10 time periods can be calculated. The plurality of time periods form a group, the vibration modes in the group are consistent, and the screening effect is convenient to test. Different groups adopt different vibration modes.

[0042] In some embodiments, the glass 1 on the screen 4 is discharged outward to a glass 1 receiving tray after reaching the target weight.

[0043] Specifically, the glass 1 on the screen 4 is cleaned after reaching the target weight to avoid damage to the screen 4 caused by excessive material accumulation, and the glass 1 on the screen 4 is discharged outward to a glass 1 receiving tray, which receives glass 1 fragments. The target weight should be less than the upper limit of the load bearing capacity of the screen 4.

[0044] The technical advantages of the method for separating the glass plate and the silicon wafer of the photovoltaic module according to the embodiments of the present application are the same as those of the photovoltaic fragment screening system described above, and will not be repeated here.

[0045] In Example 1, waste photovoltaic modules of Project A were recycled. First, the frame and junction box of the waste photovoltaic modules were removed, and then the photovoltaic panels after disassembly were calcined.

[0046] After the photovoltaic modules were calcined at 550°C, they entered the screening process.

[0047] The screen 4 is made of stainless steel wire mesh with a mesh spacing of 0.7 mm.

[0048] The system automatically tests the falling speed of the silicon wafer 2 in two vibration directions parallel to the screen 4 and perpendicular to the screen 4. Each vibration direction is continuously vibrated for 30 seconds. The weighing device uses an electronic balance with a precision of 0.01 g, and the weight of the silicon wafer 2 on the material receiving tray 3 is recorded every 1 second.

[0049] The results show that the falling speed of the silicon wafer 2 perpendicular to the screen 4 is greater.

[0050] After the data recording is completed, the system selects the vibration mode perpendicular to the screen 4, and after continuous screening for 6 minutes, the silicon wafer 2 and the glass 1 are fully separated.

[0051] Example 2

[0052] For the waste photovoltaic modules of Project B, first, the frame and junction box of the waste photovoltaic modules were removed, and then the photovoltaic panels after disassembly were calcined.

[0053] After the photovoltaic modules were calcined at 650°C, they entered the screening process.

[0054] The screen 4 is made of stainless steel wire mesh with a mesh spacing of 0.4 mm.

[0055] The system automatically tests the falling speed of the silicon wafer 2 in two vibration directions parallel to the screen 4 and perpendicular to the screen 4. Each vibration direction is continuously vibrated for 10 seconds. The weighing device uses an electronic balance with a precision of 0.01 g, and the weight of the silicon wafer 2 on the material receiving tray 3 is recorded every 0.5 seconds.

[0056] The results show that the dropping speed of the screen 4 in the 45° angle direction is greater.

[0057] After completing the data recording, the system selects the vibration mode in the 45° angle direction of the screen 4, and after continuous screening for 10 minutes, the silicon wafer 2 and the glass 1 are fully separated.

[0058] Example 3

[0059] For the recycling of waste photovoltaic modules with the name of B project, first, the removal work of waste photovoltaic module frame and junction box and the like is completed, and then the photovoltaic panel after disassembly is roasted.

[0060] After the photovoltaic module is roasted at 650°C, it enters the screening process.

[0061] The screen 4 uses a stainless steel wire mesh with a wire mesh spacing of 0.4mm.

[0062] The system is closed, and the vibration mode is not automatically selected, and the vibration mode perpendicular to the screen 4 is maintained for continuous vibration.

[0063] After continuous screening for 30 minutes, the silicon wafer 2 and the glass 1 have not been completely separated.

[0064] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0065] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0066] In the present application, unless specifically defined otherwise, the terms "mounting", "connected", "connecting", "fixed", "fixedly connected", "connection", "fixedly connected", "connected", "fixed", and the like should be construed broadly, for example, can be fixed connection, can also be detachable connection, or integral; can be mechanical connection, can also be electrical connection or communication with each other; can be directly connected, can also be indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise specifically defined. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0067] In the present application, unless specifically defined otherwise, the first feature is "on" or "under" the second feature. The first and second features can be in direct contact or indirectly contact through an intermediate medium. Moreover, the first feature "on", "above" and "on" the second feature can be directly above or obliquely above the first feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "under", "below" and "under" the second feature can be directly below or obliquely below the first feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0068] In the present application, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in the specification and the features of different embodiments or examples without contradiction.

[0069] Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Changes, modifications, replacements and variations of the above embodiments made by those skilled in the art are within the scope of the present application.

Claims

1. A photovoltaic debris screening system, characterized by, The photovoltaic chip screening system comprises a screening net, a vibrating member, a material receiving tray and a control mechanism. The screening net is used to screen the photovoltaic chips, and is a single direction screening net, the interval of the screening net is adjusted according to the equivalent diameter and thickness of the photovoltaic chips to separate the glass and the silicon chips. The vibrating member is used to drive the screening net to vibrate. The material receiving tray is used to receive the screened photovoltaic chips. The control mechanism comprises a weighing device and a vibration control device, the vibration control device is connected with the vibrating member to control the vibration of the vibrating member, the weighing device is electrically connected with the vibration control device to send the weight information of the silicon chip material on the screening net to the vibration control device, the vibration control device controls the vibration of the vibrating member according to the weight information of the silicon chip material, the vibration control device comprises a data processor, the weighing device records the weight of the material receiving tray within a preset time period, the data processor obtains the falling speed of the silicon chip material according to the time and weight data, and the vibration control device controls the vibration of the vibrating member according to the falling speed of the silicon chip material.

2. The photovoltaic debris screening system of claim 1, wherein, The interval of the screening net is 0.2mm-1mm.

3. A method for separating a photovoltaic module glass panel and a silicon wafer, characterized in that, The photovoltaic chip screening system comprises the following steps: The photovoltaic panel is baked in a preset temperature range; The material chips after baking are collected; The material chips are screened by starting the screening system, the screening system is the photovoltaic chip screening system according to any one of claims 1-2, and the screening system obtains the vibration mode with the maximum screening efficiency according to the falling speed of the silicon chip; The vibrating member maintains the vibration mode with the maximum screening efficiency until the screening is completed.

4. The method for separating the photovoltaic module glass plate and silicon wafer according to claim 3, characterized in that, After the large size broken pieces and long strip solder strips in the material chips after baking are picked out, the glass in the material chips after baking is broken into fragments with an equivalent diameter of 3-8mm, and the silicon chips are broken into irregular thin pieces with a thickness of 0-0.2mm.

5. The method for separating the photovoltaic module glass plate and silicon wafer according to claim 3, characterized in that, The weight difference value is obtained by subtracting the weight of the silicon chip in the adjacent time period from the weight value of the silicon chip in the target time period, and the falling speed of the silicon chip is the ratio of the weight difference value to the time period.

6. The method of claim 3, wherein the glass sheet is a photovoltaic module glass sheet. The screening net maintains the same vibration mode in several time periods, all the vibration modes are traversed to obtain the vibration mode with the maximum falling speed of the silicon chip, and the screening mode with the highest screening efficiency is obtained.

7. The method of claim 3, wherein the method further comprises: The glass on the screening net is discharged to the glass receiving tray after reaching the target weight.

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