How to separate waste solar panels

Abstract

To provide a separation method capable of finely dividing and recovering each substance contained in a discarded solar panel. [Solution] The method for separating waste solar panels according to the present invention includes a crushing step in which solar panels to be discarded are crushed into fragments, and a specific gravity separation step in which wind power is applied to the fragments resulting from the crushing step to separate them according to their specific gravity. Preferably, the method for separating waste solar panels also includes a magnetic separation step in which the processed materials separated as a group with a relatively high specific gravity in the specific gravity separation step are further subdivided and sorted based on the presence or absence of magnetism.

Description

[Technical Field]

[0001] In recent years, environmental concerns have led to a growing awareness of recycling worldwide, and as a result, technology for separating and reusing reusable materials from discarded solar panels has been attracting attention. [Background technology]

[0002] As an example of such technology, Patent Document 1 discloses a method for separating precious metals from solar panels to be discarded. Specifically, Patent Document 1 describes a solar panel separating device for a solar panel portion to be heated, which is a part of a solar panel to be discarded, in which the solar panel portion to be heated has a plurality of solar cells sealed with a remaining sealant, the device comprising: a first conveying mechanism for conveying the solar panel portion to be heated; and a first heating mechanism for performing a first local heating process on the remaining sealant of the solar panel portion to be heated conveyed by the first conveying mechanism, the first local heating process being performed at a first temperature in a first heating target region; The separating device for a solar panel is disclosed, wherein the first heating target area includes a contact area of ​​the remaining sealing material with the plurality of solar cells, the first local heating treatment is performed without contact with the solar panel portion to be heated, the first temperature is set to a temperature at which the remaining sealing material decomposes, and each of the plurality of solar cells has a precious metal formation area where a precious metal is provided on a surface thereof, and the device further includes a second transport mechanism that transports the plurality of solar cells independently on a cell-by-cell basis, and a second heating mechanism that performs a second local heating treatment on each of the plurality of solar cells transported by the second transport mechanism, by locally heating the second heating target area at a second temperature, the second heating target area includes the precious metal formation area, the second local heating treatment is performed without contact with each of the plurality of solar cells, the second temperature is set to a temperature at which the precious metal melts, and the first temperature is set to a temperature at which the precious metal does not melt. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7214326 Summary of the Invention [Problem to be solved by the invention]

[0004] The separation method described in Patent Document 1 has the advantage that it is possible to separate multiple solar cells and to dissolve, separate, and recover the precious metals contained in each solar cell. However, this document does not disclose a means for further separating and recovering the separated and recovered precious metals into individual substances, and further improvements are desired.

[0005] An object of the present invention is to provide a separation method that can further subdivide and recover each substance contained in waste solar panels. [Means for solving the problem]

[0006] The method for separating waste solar panels according to the present invention includes a crushing step of crushing the solar panels to be discarded into fragments, and a separating step of separating the fragments generated through the crushing step. The resulting fragments are sieved using a conveying surface having a mesh structure, and the resulting fragments are allowed to fall by their own weight while being vibrated and Separation by specific gravity using wind power By wind gravity separator a gravity separation step, and a treated substance separated as a group having a relatively large specific gravity in the gravity separation step; After passing through the color sorting process, metal detection process and magnetic sorting process, the dissolution and separation temperature corresponding to each substance is specified, and a high-frequency induction heating step for performing high-frequency induction heating treatment. do.

[0007] This allows the various substances contained in discarded solar panels to be recovered in a more detailed manner than before, contributing to more appropriate reuse of each substance.

[0008] In addition, in the separation method for waste solar panels according to the present invention, it is preferable to have a magnetic separation process in which the processed materials separated as a group with a relatively high specific gravity in the specific gravity separation process are further subdivided and sorted based on whether or not they are magnetic.

[0009] This allows magnetic materials such as metal alloys to be separated and sorted from non-magnetic materials such as glass and silicon before recovery, further contributing to recycling.

[0010] In addition, in the separation method for waste solar panels according to the present invention, it is preferable to have a color sorting process in which the processed materials separated as a group with a relatively high specific gravity in the specific gravity separation process are further subdivided and sorted based on differences in color.

[0011] This allows the processed materials separated from waste solar panels to be further subdivided and collected based on differences in color, which can contribute to recycling.

[0012] Furthermore, in the separation method for waste solar panels according to the present invention, it is preferable to have a metal detection sorting process in which the processed materials separated as a group with a relatively high specific gravity in the specific gravity separation process are further subdivided and sorted using a metal detector.

[0013] This allows the processed material separated from the waste solar panels to be further broken down and collected based on the results of detection by the metal detector, contributing to recycling.

[0014] In addition, it is preferable that the waste solar panel separation method according to the present invention further comprises a high-frequency induction heating step in which the processed material separated as a group with a relatively high specific gravity in the specific gravity separation step is subjected to high-frequency induction heating.

[0015] According to this method, after the treated material separated from the waste solar panels is broken down and collected, the dioxins can be thermally decomposed to make them non-toxic, making it possible to recycle the treated material more safely. [Effects of the Invention]

[0016] According to the separation method of the present invention, it is possible to further separate and recover each substance contained in the waste solar panels. [Brief explanation of the drawings]

[0017] [Figure 1] 1A to 1C are diagrams for schematically explaining each step of a waste solar panel separation method according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing details of the crushing step in the waste solar panel separation method according to the embodiment of the present invention. [Figure 3] FIG. 2 is a diagram showing details of the gravity separation step in the separation method for waste solar panels according to an embodiment of the present invention. [Figure 4] FIG. 2 is a diagram showing a process subsequent to the gravity separation process in the separation method for waste solar panels according to an embodiment of the present invention. [Figure 5] FIG. 2 is a diagram showing details of a magnetic separation step in the separation method for waste solar panels according to an embodiment of the present invention. [Figure 6] FIG. 2 is a diagram showing details of a high-frequency induction heating process in the method for separating waste solar panels according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following, similar elements in all drawings will be designated by the same reference numerals, and duplicate explanations will be omitted. Furthermore, in the description below, previously described reference numerals will be used as necessary.

[0019] First, the separation method according to the present invention, which is used to crush and fragment solar panels to be discarded (hereinafter sometimes referred to as waste solar panels) for recycling, will be described with reference to Figures 1 to 5.

[0020] FIG. 1 is a diagram for explaining each step of a waste solar panel separation method according to an embodiment of the present invention.

[0021] As shown in Figure 1, the separation method for waste solar panels according to an embodiment of the present invention includes a crushing step, a specific gravity separation step, a color sorting step, a metal detection sorting step, a magnetic sorting step, and a high-frequency induction heating step. Each of these steps will be described in order below.

[0022] <Crushing process> 2 is a diagram showing details of the crushing step in the separation method for waste solar panels S according to an embodiment of the present invention. In detail, the crushing step includes a primary crushing step in which crushing is performed using a biaxial crusher, and a secondary crushing step in which crushing is performed using a uniaxial crusher.

[0023] In the crushing process, first, the waste solar panels S are placed in order on the conveying surface by an operator at the upstream end of the first conveyor 10. The waste solar panels S that reach the downstream end of the first conveyor 10 are placed into a first box 60 that houses a biaxial crusher 61.

[0024] The biaxial crusher 61 is composed of a first rotary blade 61a and a second rotary blade 61b that rotate in opposite directions. The waste solar panels S placed in the first box 60 are roughly crushed into coarse fragments by the action of the first rotary blade 61a and the second rotary blade 61b. Depending on the shape and spacing of the blades of the first rotary blade 61a and the second rotary blade 61b, the size of the coarse fragments P1 after processing may be, for example, 100 mm or less.

[0025] The bottom end of the first box 60 is open, and the coarse fragments P1 fall naturally under gravity to the upstream end of the second conveyor 20 and are deposited on the conveying surface of the second conveyor 20. The conveying surface of the second conveyor 20 is configured with a mesh of 20-60 mm, preferably 25-55 mm, and more preferably 30-50 mm. In this embodiment, the conveying surface of the second conveyor 20 has a mesh of 30 mm, and the coarse fragments P1 are sieved by this conveying surface, so that only coarse fragments P1 of 30 mm to 50 mm or larger are fed to the uniaxial crusher 71. This improves the efficiency of crushing. The coarse fragments P1 that reach the downstream end of the second conveyor 20 fall naturally into the second box 70. The uniaxial crusher 71 is housed in the second box 70.

[0026] The uniaxial crusher 71 includes a rotating blade 71a that rotates in one direction and a curved particle size adjustment screen 71b that covers the lower half of the rotating blade 71a from below. The particle size adjustment screen 71b has a mesh structure with an appropriate coarseness depending on the desired size of the crushed fragments. The shape of the blades of the rotating blade 71a depends on the spacing and the coarseness of the mesh, but the size of the fragments after processing by the uniaxial crusher 71 may be, for example, 10 mm or less. The processed fragments obtained in this manner are placed on the conveying surface of the third conveyor 30, which is inclined so that it becomes higher toward the downstream side, and are then subjected to the next process, the gravity separation process. Specifically, the fragments transported to the downstream end of the third conveyor 30 fall naturally and are supplied to the inlet 80a of the air-powered gravity separator 80.

[0027] <Specific gravity separation process> FIG. 3 is a diagram showing details of the gravity separation process in the separation method for waste solar panels S according to an embodiment of the present invention. In the gravity separation process, as shown in FIG. 3, fragments P2 obtained through the crushing process are supplied to an air-powered gravity separator 80. The air-powered gravity separator 80 includes a cylindrical body 81 tilted so that the upstream side is higher than the downstream side, a wind source 82 disposed at the downstream end of the cylindrical body 81, a vibration motor 83 provided to vibrate the cylindrical body 81, and a heavy-weight object drop port 81a, a medium-weight object drop port 81b, and a light-weight object drop port 81c disposed in this order from downstream to upstream at the bottom of the cylindrical body. The cylindrical body 81 is supported by a support 85 via a spring 84, so that the cylindrical body 81 vibrates in response to vibrations generated by the vibration motor 83.

[0028] When the fragments P2 obtained through the crushing process are supplied into the cylindrical body 81, the fragments are blown away by the wind from the wind source 82 and the vibrations applied by the vibration motor 83, causing the fragments to fall unevenly at appropriate locations within the cylindrical body 81 according to their specific gravity. Specifically, fragments categorized as heavy objects fall downward from the heavy object drop port 81a, fragments with a specific gravity relatively smaller than that of heavy objects fall downward from the medium object drop port 81b, and fragments with a specific gravity even smaller than that of medium objects fall downward from the small object drop port 81c. The fragments that fall from each drop port 81a, 81b, 81c are separated and collected in collection boxes that are pre-arranged below the drop ports.

[0029] <Color sorting process> The processed materials separated into groups with a relatively large specific gravity, specifically, processed materials classified as heavy and medium weight items in this embodiment, are each placed by an operator at the upstream end of the horizontal conveyor 50. In other words, the debris separated as light weight items (plastic, rubber, film, etc.) can be reused as building materials as is, and are therefore separated and collected in this state. The debris classified into other groups (medium weight and heavy weight items) is preferably further broken down and collected, and is therefore placed individually on the horizontal conveyor 50 for subsequent processing.

[0030] The fragments placed on the horizontal conveyor 50 are processed by a color sorter 130 shown in Figure 4, where they are separated according to color differences. This makes it possible to separate and sort glass fragments and other debris that could not be sorted by gravity separation alone after crushing.

[0031] <Metal detection process> After the color sorting process, the fragments are then processed by a metal detector 90 shown in Figure 4, where they are separated into metal and non-metallic fragments. This allows the fragments of discarded solar panels to be roughly sorted into metal and non-metallic fragments in a process prior to magnetic sorting, which ultimately enables a more advanced material cycle. In this embodiment, an operator is always on standby downstream of the metal detector 90 to perform visual sorting by the operator in addition to the detection results from the metal detection process in order to improve accuracy.

[0032] <Magnetic sorting process> A magnetic sorting mechanism 100 shown in Fig. 4 is disposed at the downstream end of the horizontal conveyor 50. As shown in Fig. 5, the magnetic sorting mechanism 100 is configured to include a rotor 101 made of a magnet, and a branch plate 102 for separating fragments attracted by magnetic force to the rotor 101 from other fragments. As a result, the fragments supplied to the magnetic sorting mechanism 100 are separated into magnetic materials (e.g., iron and alloys containing iron) and non-magnetic materials (e.g., glass, silicon, etc.) by the interaction between the rotor 101 and the branch plate 102. Fig. 5 is a diagram showing details of the magnetic sorting step in the waste solar panel separation method of this embodiment.

[0033] <High frequency induction heating process> Each fragment broken down through the color sorting process, metal detection process, and magnetic sorting process is subjected to high-frequency induction heating at a temperature appropriate for the dissolution and separation of each material. Heating device 120, which applies high-frequency induction heating, is equipped with a known auxiliary device 121 used to reduce dioxin emissions. This allows for thermal decomposition of dioxins, and the dioxins can be rendered harmless through treatment by auxiliary device 121. As a result, the safety and convenience of the fragments produced for recycling can be improved when they are reused as building materials, other building materials, etc.

[0034] As described above, the method for separating waste solar panels according to this embodiment includes a crushing process in which the solar panel S to be discarded is crushed into fragments, and a specific gravity separation process in which wind force is applied to the fragments produced through this crushing process to separate them according to their specific gravity.

[0035] This allows the various substances contained in the waste solar panels S to be recovered in a more detailed manner than before, which contributes to recycling.

[0036] In addition, the separation method for waste solar panels S according to this embodiment includes a magnetic separation process in which the processed materials separated as a group with a relatively high specific gravity in the specific gravity separation process are further subdivided and sorted based on whether or not they are magnetic.

[0037] This allows iron and alloys containing iron to be separated and sorted from non-magnetic materials such as glass and silicon before being recovered, further contributing to recycling.

[0038] In addition, the separation method for waste solar panels S according to this embodiment includes a color sorting process in which the processed materials separated as a group with a relatively high specific gravity in the specific gravity separation process are further subdivided and sorted based on differences in color.

[0039] This allows the processed materials separated from the waste solar panels S to be further subdivided and collected based on differences in color. Normally, each substance contained in the waste solar panels S has a different color depending on the composition of the substance, so by separating each substance based on differences in color, it may be possible to reuse each substance using a more appropriate recycling method.

[0040] Furthermore, the separation method for waste solar panels S according to this embodiment also includes a metal detection sorting step in which the processed materials separated as groups with relatively high specific gravities in the specific gravity separation step are further subdivided using a metal detector 90. Typically, by classifying each substance contained in the waste solar panels S according to whether it is a metal or not, it becomes possible to separate and recover each substance more finely. As a result, each substance can be reused for a more appropriate purpose.

[0041] According to this, the processed material separated from the waste solar panel S can be further subdivided and collected based on the detection results of the metal detector 90, which can contribute to recycling.

[0042] Moreover, the separation method for waste solar panels S according to this embodiment further includes a high-frequency induction heating step of high-frequency induction heating the processed materials separated as a group with a relatively large specific gravity in the specific gravity separation step.

[0043] According to this, after the treated material separated from the waste solar panels S is fragmented and collected, the dioxins can be thermally decomposed to make them non-toxic, and the treated material can be recycled more safely. Note that in order to reliably suppress the emission of dioxins, the high-frequency induction heating device 120 may be provided with a temperature reducing tower, a dust collector, or the like.

[0044] As a result, according to the method for separating waste solar panels S of this embodiment, the fragments produced by crushing the waste solar panels S can be sorted from multiple perspectives, such as differences in specific gravity, differences in color, whether they are metallic or not, and differences in magnetic force, which can contribute to more advanced recycling of the materials (including expensive precious metals) contained in the waste solar panels S.

[0045] Furthermore, for example, if a separation method such as that of the present invention is applied when processing waste solar panels based on the main components and process chart of solar panels published by the manufacturer of solar panels used in large-scale solar power plants, this can advantageously lead to a significant improvement in the recycling rate of the waste solar panels.

[0046] In the separation method for waste solar panels S according to this embodiment, the processed material that has undergone the specific gravity separation process is described as being sorted using a color sorting process, a metal detection process, and a magnetic sorting process, but these processes may be selected appropriately depending on the processed material before sorting. [Explanation of symbols]

[0047] S Waste solar panels, 61 Biaxial crusher, 71 Single-axis crusher, P1 Coarse debris, P2 Debris, 80 Air-powered gravity separator, 130 Color sorter, 90 Metal detector, 100 Magnetic sorting mechanism

Claims

1. A crushing process for crushing the solar panels to be disposed of into fragments; a gravity separation process using a wind-powered gravity separator in which the fragments generated in the crushing process are sieved using a conveying surface having a mesh structure, and the resulting fragments are allowed to fall by their own weight while being subjected to vibration and wind force to separate them according to their specific gravity; a high-frequency induction heating process in which the processed materials separated as a group with a relatively high specific gravity in the specific gravity separation process are subjected to a color sorting process, a metal detection process, and a magnetic sorting process, and then subjected to a high-frequency induction heating process at a specific dissolution and separation temperature corresponding to each material; A method for separating waste solar panels, comprising:

2. The method for separating waste solar panels according to claim 1, A method for separating waste solar panels, characterized by including a magnetic separation process in which the processed materials separated as a group with a relatively high specific gravity in the specific gravity separation process are further subdivided and sorted based on whether or not they are magnetic.

3. The method for separating waste solar panels according to claim 1, A method for separating waste solar panels, characterized by including a color sorting process in which the processed materials separated as a group with a relatively high specific gravity in the specific gravity separation process are further subdivided and sorted based on differences in color.

4. The method for separating waste solar panels according to claim 1, A method for separating waste solar panels, characterized by including a metal detection sorting process in which the processed materials separated as a group with a relatively high specific gravity in the specific gravity separation process are further subdivided and sorted using a metal detector.

Images