Continuous heating device, recycling system for components of solar panels

Abstract

The present invention provides a continuous heating device and a recycling system for components of a solar panel equipped with the continuous heating device. The continuous heating device improves the thermal efficiency of the solar panel in heat treatment, thereby reducing energy costs and improving the quality of valuables recovered from the solar panel. The continuous heating device (100) includes a heating furnace (20), which has a primary processing section (13) for obtaining a primary processed product (2) by heat treatment under a non-oxidizing atmosphere while conveying the solar panel (1) with an annular belt (21), and a secondary processing section (15) for obtaining a heat-treated product (3) by heat treatment under an oxidizing atmosphere while conveying the primary processed product (2) with an annular belt (21). At least one of the primary processing section (13) and the secondary processing section (15) utilizes the heat energy generated by the combustion of thermal decomposition gases produced when the sealing material of the solar panel (1) is decomposed during heat treatment in the primary processing section (13).

Description

Technical Field

[0001] This invention relates to a continuous heating device and a recycling system for components of a solar panel. Background Technology

[0002] To effectively utilize resources, research is underway on recycling solar cells and glass from used solar panels. With the anticipated increase in solar panel waste, the importance of reusing its components has risen. For example, by removing the aluminum frame of a solar panel, the aluminum plate can be recycled. Furthermore, by removing adhesives, sealants, and other resins from solar panels, glass, copper wire, and silicon solar cells can be recycled.

[0003] Methods for removing resins such as sealant from solar panels include wet processing methods that use a processing liquid to decompose or separate the resin, and processing methods that vaporize the resin through heat treatment. However, from the perspective of continuous processing, heat treatment is preferred. For example, Patent Document 1 discloses a method of separating and recovering glass raw materials and metal-containing raw materials from the heat-treated product after heat treatment of the solar panel. In the embodiment of Patent Document 1, a first firing is performed under a nitrogen atmosphere, followed by a second firing under air, thereby decomposing the organic compounds in the solar panel.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2023-89446 Summary of the Invention

[0007] However, in the heating furnace used in the embodiment of Patent Document 1, after the solar panels are fired once in a nitrogen atmosphere, the heat-treated material needs to be cooled once before a second firing. Therefore, in order to perform a second firing, the treated material obtained in the first firing needs to be heated again. As a result, there are problems of poor thermal efficiency and increased energy costs in the heat treatment of solar panels. In addition, coal from resin residue may sometimes adhere to the heat-treated material, so the quality of valuable materials recovered in the sorting process after heat treatment may also be affected.

[0008] The present invention provides a continuous heating device and a recycling system for components of a solar panel equipped with the continuous heating device. The continuous heating device can improve the thermal efficiency in the heat treatment of solar panels, reduce energy costs, and improve the quality of valuables recovered from solar panels.

[0009] Methods for solving problems

[0010] The present invention has the following aspects.

[0011] [1] A continuous heating apparatus comprising a heating furnace, wherein the heating furnace obtains a heat-treated product by heat treatment while conveying a solar panel via an annular belt; the heating furnace having a primary processing section and a secondary processing section, wherein the primary processing section obtains a primary product by heat treatment while conveying the solar panel via the annular belt under a non-oxidizing atmosphere, and the secondary processing section obtains the heat-treated product by heat treatment while conveying the primary product via the annular belt under an oxidizing atmosphere; at least one of the primary processing section and the secondary processing section utilizes heat energy generated by the combustion of thermal decomposition gases produced when the sealing material of the solar panel is decomposed by heat treatment in the primary processing section.

[0012] [2] According to the continuous heating device described in [1], a flexible sealing curtain that traverses the conveying direction of the solar panel and contacts the annular belt is suspended in at least one place inside the heating furnace.

[0013] [3] According to the continuous heating device described in [2], the sealing curtain is suspended in the heating furnace between the primary processing unit and the secondary processing unit.

[0014] [4] According to the continuous heating device described in [2] or [3], the sealing curtain is suspended in the heating furnace upstream of the primary processing unit.

[0015] [5] The continuous heating apparatus according to any one of [2] to [4], wherein the sealing curtain is suspended in the heating furnace downstream of the secondary processing unit.

[0016] [6] The continuous heating apparatus according to any one of [1] to [5], wherein at least one of the primary processing unit and the secondary processing unit utilizes the thermal energy of the waste gas generated after the thermal decomposition gas is burned.

[0017] [7] The continuous heating apparatus according to any one of [1] to [6] further includes a combustion chamber for burning the thermal decomposition gas generated when the sealing material of the solar panel is decomposed by heat treatment in the primary processing section.

[0018] [8] According to the continuous heating device of [7], at least one of the primary processing unit and the secondary processing unit utilizes the thermal energy of the exhaust gas discharged from the combustion chamber.

[0019] [9] The continuous heating apparatus according to any one of [1] to [8], wherein a heat exchanger utilizing the heat energy generated by the combustion of the above-mentioned thermally decomposed gas is disposed in at least one of the above-mentioned primary processing unit and the above-mentioned secondary processing unit.

[0020]

[10] According to the continuous heating device described in [9], the heat exchanger utilizes the thermal energy of the waste gas generated after the thermal decomposition gas is burned.

[0021]

[11] According to the continuous heating device of [9] or

[10] , the heating furnace has a muffle furnace surrounded by the annular belt and an outer wall surrounded by the muffle furnace, and the heat exchanger is arranged in the space between the muffle furnace and the outer wall.

[0022]

[12] The continuous heating device according to any one of [9] to

[11] , wherein the heat exchanger is an indirect heat exchanger.

[0023]

[13] According to the continuous heating device described in

[11] or

[12] , an electric heater is disposed in the space between the muffle furnace and the outer wall.

[0024]

[14] The continuous heating apparatus according to any one of [1] to

[13] , wherein the amount of coal adhering to the above-mentioned heated material is 100 ppm or less.

[0025]

[15] A recycling system for components of a solar panel, comprising a continuous heating device as described in any one of [1] to

[14] and a sorting device for separating glass raw materials and valuable metal contents from the heat-treated material.

[0026]

[16] The recycling system for the constituent components of the solar panel according to

[15] , wherein the sorting device has a screening processing unit that screens the heat-treated material into a first valuable metal containing solar cells and copper wire and a first glass raw material.

[0027]

[17] According to the recycling system of the constituent components of the solar panel described in

[16] , the sorting device further includes a wind sorting section, which sorts the first glass raw material after being screened by the screening processing section into a second valuable metal containing the solar cell and a second glass raw material by wind sorting.

[0028]

[18] The recycling system for the constituent components of the solar panel according to

[17] further includes an air shaker sorting section that uses an air shaker to sort the third glass raw material from the second glass raw material.

[0029]

[19] According to the recycling system for the constituent components of the solar panel described in

[18] , the glass purity of the sorted third glass raw material is 99.99% or higher.

[0030]

[20] A recycling system for the constituent components of a solar panel according to any one of

[15] to

[19] , wherein the recycling rate of the glass raw material contained in the heat-treated material is 85% or more.

[0031]

[21] A recycling system for the constituent components of a solar panel according to any one of

[15] to

[20] , wherein the recycling rate of the solar cells contained in the heat-treated material is 90% or more.

[0032]

[22] A recycling system for the constituent components of a solar panel according to any one of

[15] to

[21] , wherein the recycling rate of the copper wire contained in the heat-treated material is 90% or more.

[0033] Invention Effects

[0034] According to the present invention, the thermal efficiency in the heat treatment of solar panels can be improved, energy costs can be reduced, and the quality of valuables recovered from solar panels can be improved. Attached Figure Description

[0035] Figure 1 This is a schematic diagram illustrating an example of a continuous heating device.

[0036] Figure 2 View from the entrance side Figure 1 A schematic diagram of a continuous heating device.

[0037] Figure 3 It is Figure 1 A magnified 3D view of a continuous heating device.

[0038] Figure 4 This is a diagram showing the sealing curtain as viewed from the direction the solar panels are being transported.

[0039] Figure 5 This is a side view of the solar panels being conveyed as they are pushed up through the sealing curtain inside the heating furnace.

[0040] Figure 6 This is a diagram showing the solar panels being conveyed in the sealed chamber of the heating furnace, viewed from the rear side of the conveying direction, as one side of the solar panel pushes up the sealing curtain.

[0041] Figure 7This is a diagram showing the solar panels being conveyed in the sealed chamber of the heating furnace, viewed from the rear side of the conveying direction, as one side of the solar panel pushes up the sealing curtain.

[0042] Figure 8 This is a schematic diagram illustrating an example of a recycling system for the components of a solar panel.

[0043] Figure 9 This is a schematic diagram illustrating another example of a recycling system for the components of a solar panel.

[0044] Figure 10 This refers to the glass fragments recovered from the heat-treated product obtained in Example 1.

[0045] Figure 11 This refers to the glass fragments recovered from the heat-treated product obtained in Comparative Example 1. Detailed Implementation

[0046] [the term]

[0047] "Non-oxidizing atmosphere" refers to an atmosphere that does not contain oxygen or is substantially free of oxygen.

[0048] "Oxidizing atmosphere" refers to an atmosphere containing oxygen, which is an atmosphere other than a non-oxidizing atmosphere.

[0049] In this specification and claims, the "~" sign indicating a numerical range means that the numerical values ​​before and after it are included as the lower limit and upper limit.

[0050] [Solar panels]

[0051] In one example, the solar panel includes solar cells, a glass substrate, and sealing material. In other examples, the solar panel may also include wiring electrodes, lead electrodes, terminal boxes, cables, a backsheet, a frame, etc.

[0052] It is preferable to perform heat treatment on the solar panels from which the cables have been removed.

[0053] From the perspective of reducing the number of processes, it is preferable to perform heat treatment without removing the backsheet, terminal box, and aluminum frame from the solar panel.

[0054] Examples of solar cell types for solar panels include silicon-based (monocrystalline silicon, polycrystalline silicon, amorphous silicon, etc.) and compound-based (GaAs, CIS, CdTe-CdS) cells. Monocrystalline silicon and polycrystalline silicon are preferred.

[0055] Examples of glass substrates used in solar panels include soda-lime glass and alkali-free glass.

[0056] Examples of sealing materials used in solar panels include ethylene-vinyl acetate copolymer (EVA) and ethylene-(meth)acrylate copolymer. Among these, EVA is widely used.

[0057] [Thermal decomposition gases]

[0058] Thermal decomposition gases are generated during the thermal decomposition of the sealing materials in solar panels. These gases are produced due to the thermal decomposition of resins in the sealing materials. Solar panels primarily use various resins, polymers, and other organic compounds as sealing materials. Examples of the constituent elements of these organic compounds include carbon, nitrogen, fluorine, hydrogen, and oxygen. These organic compounds decompose and vaporize upon heating, thereby producing thermal decomposition gases.

[0059] In the first treatment, the resin is vaporized and carbonized by heating in a non-oxidizing atmosphere. In the second treatment, it is heated in an oxidizing atmosphere, thereby oxidizing and removing the carbon deposits adhering to the heat-treated material after the first treatment. The thermal decomposition gas produced in the first treatment contains more combustible gases than the oxidizing gases such as CO2 produced in the second treatment. The continuous heating apparatus of the present invention is characterized by utilizing the heat energy generated from the combustion of the thermal decomposition gas containing more combustible gases produced in the first treatment, in order to improve thermal efficiency in heat treatment and reduce energy costs.

[0060] Hereinafter, several embodiments will be described with appropriate reference to the accompanying drawings. The following description relates to representative examples of embodiments of the invention, and the invention is not limited to the following description. In addition, for ease of explanation, the dimensional ratios in the drawings may sometimes differ from the actual dimensions.

[0061] [Continuous heating device]

[0062] Figure 1 This is a schematic diagram illustrating an example of a continuous heating device. The continuous heating device 100 includes a heating furnace 20, a combustion chamber 40, a first gas supply unit (not shown) that supplies inactive gas to the heating furnace 20, and a second gas supply unit that supplies oxygen-containing gas to the heating furnace 20. The heating furnace 20 heats and processes solar panels 1 while conveying them via an annular belt 21 to obtain a heat-treated product. The combustion chamber 40 is used to burn the thermal decomposition gases generated during the heat treatment and decomposition of the sealing material of the solar panels 1 in the primary processing section 13 of the heating furnace 20.

[0063] The heating furnace 20 has, from upstream to downstream, a transfer inlet side exhaust chamber 11, a transfer inlet side sealing chamber 12, a primary processing section 13, a switching section 14, a secondary processing section 15, an air cooling chamber 16, a cooling chamber 17, a transfer outlet side sealing chamber 18, and a transfer outlet side exhaust chamber 19.

[0064] Figure 2 Viewed from the side of entrance 11a Figure 1 A schematic diagram of the continuous heating device 100. Figure 3 This is a magnified three-dimensional view of a portion of the continuous heating device 100. For example... Figure 2 As shown, the heating furnace 20 has a muffle furnace 27 surrounded by a covering annular belt 21 and an outer wall 28 surrounding the muffle furnace 27. Although in Figure 3 The illustration is omitted, but the muffle furnace 27 and the outer wall 28 each have a structure that extends along the conveying direction of the annular belt 21.

[0065] The muffle furnace 27 has a primary processing section 13, a switching section 14, and a secondary processing section 15.

[0066] The outer wall 28 covers the muffle furnace 27, a pair of electric heaters 29, a first heat exchanger 31, and a second heat exchanger 32. Due to the outer wall 28, thermal fluctuations can be suppressed, thus maintaining the temperatures of the primary processing section 13 and the secondary processing section 15 at appropriate heat treatment temperatures. Temperature can be adjusted by controlling the output of each electric heater 29 according to the temperatures of the primary processing section 13 and the secondary processing section 15 within the muffle furnace 27.

[0067] An inlet 11a is formed in the inlet-side exhaust chamber 11 for transferring the solar panel 1 into the heating furnace 20. The inlet-side exhaust chamber 11 is a region for exhausting the external gas flowing in from the inlet 11a together with the inactive gas and thermal decomposition gas from the inlet-side sealed chamber 12.

[0068] In one example, an opening adjustment plate for adjusting the opening of the passage (inlet 11a) of the heating furnace 20 can also be provided at the inlet 11a.

[0069] An exhaust port 11b is formed at the upper part of the intake port side exhaust chamber 11. The exhaust port 11b is used to discharge the external gas flowing in from the intake port 11a together with the inactive gas and thermal decomposition gas from the intake port side sealing chamber 12. An exhaust pipe 71 is connected to one end of the exhaust port 11b.

[0070] In one example, an opening adjustment unit for adjusting the opening degree can also be provided at the exhaust port 11b. An opening adjustment plate can be cited as an example of such an opening adjustment unit.

[0071] The inlet-side sealing chamber 12 is an area used to suppress the intrusion of external gas into the primary processing unit 13 and the leakage of inactive gas and thermal decomposition gas from the primary processing unit 13.

[0072] An inert gas inlet (not shown) is formed at the upper part of the inlet-side sealing chamber 12 for introducing inert gas supplied from the first gas supply unit (not shown) into the inert gas inlet-side sealing chamber 12.

[0073] A flexible sealing curtain 22 is suspended in the inlet-side sealing chamber 12. The sealing curtain 22 crosses the transport direction of the solar panel 1 and contacts the annular belt 21. In one example, an opening adjustment plate (not shown) for adjusting the opening of the passage of the heating furnace 20 (the inlet of the inlet-side sealing chamber 12) may be provided in the inlet-side sealing chamber 12 upstream of the sealing curtain 22.

[0074] The vertical length of the sealing curtain 22 only needs to be the length that contacts the annular belt 21 inside the heating furnace 20. Preferably, the lower end of the sealing curtain 22 contacts the annular belt 21, and more preferably, the lower end of the sealing curtain 22 is pressed against the annular belt 21 and flexed.

[0075] The sealing curtain 22 only needs to be flexible and heat-resistant. For example, a thin sheet can be used as the sealing curtain 22. A thin sheet with good heat resistance is preferred, and a thin metal sheet is more preferred.

[0076] In the inlet-side sealing chamber 12, multiple sealing curtains 22 are suspended at intervals in the transport direction of the solar panel 1. The number of sealing curtains 22 is preferably 2 to 100, more preferably 10 to 85, and even more preferably 20 to 70. If the number of sealing curtains 22 is above or below the lower limit of the above range, the intrusion of external gas into the primary processing unit 13 and the leakage of inactive gas and thermal decomposition gas from the primary processing unit 13 can be sufficiently suppressed. If the number of sealing curtains 22 is below the upper limit of the above range, the solar panel 1 can easily pass through the inlet-side sealing chamber 12.

[0077] like Figure 4As shown, the sealing curtain 22 is composed of a plurality of strips 22A arranged without gaps in the direction traversing the transport direction of the solar panel 1 and extending in the vertical direction. The number of strips 22A per 1m in the width direction of the sealing curtain 22 is preferably 2 to 50 strips / m, more preferably 10 to 30 strips / m. If the number of strips 22A is above the lower limit of the above range, the gap between the side of the solar panel 1 and the strips 22A can be minimized as much as possible according to the working mechanism described later. Therefore, the intrusion of external gas into the primary processing unit 13 and the leakage of inactive gas and thermally decomposed gas from the primary processing unit 13 can be sufficiently suppressed. If the number of strips 22A is below the upper limit of the above range, the number of gaps between adjacent strips 22A can be suppressed. Therefore, the intrusion of external gas into the primary processing unit 13 and the leakage of inactive gas and thermally decomposed gas from the primary processing unit 13 can be sufficiently suppressed.

[0078] The primary processing unit 13 is a region for obtaining a primary processed product by heat treatment in a non-oxidizing atmosphere while conveying the solar panel 1 via the annular belt 21. An inert gas inlet (not shown) is formed at the top of the primary processing unit 13 for introducing an inert gas supplied from the first gas supply unit (not shown) into the primary processing unit 13.

[0079] like Figure 2 As shown, a pair of electric heaters 29 are provided in the space between the muffle furnace 27 and the outer wall 28 in the conveying direction of the annular belt 21. In the primary processing unit 13, the pair of electric heaters 29 sandwich the muffle furnace 27, which is equipped with the annular belt 21 for conveying solar panels 1, and are provided in the conveying direction of the solar panels 1.

[0080] In the primary processing unit 13, the solar panel 1 is subjected to heat treatment, and a portion of the resin contained in the solar panel 1 is thermally decomposed, resulting in a primary processed product 2.

[0081] An exhaust port 13a is formed at the upper part of the primary processing unit 13. The exhaust port 13a is used to discharge the thermal decomposition gas generated by the thermal decomposition of the resin of the sealing material and the like contained in the solar panel 1, together with the inactive gas, from the primary processing unit 13. The thermal decomposition gas generated here flows in the thermal decomposition gas supply pipe 61 connected to the exhaust port 13a and is supplied to the combustion chamber 40.

[0082] The switching section 14 is a region used to switch between primary processing under a non-oxidizing atmosphere and secondary processing under an oxidizing atmosphere. An inlet (not shown) is formed on the upper part of the switching section 14 for introducing inactive gas supplied from the first gas supply unit (not shown) into the switching section 14.

[0083] Inside the heating furnace 20 of the switching section 14 located between the primary processing section 13 and the secondary processing section 15, multiple sealing curtains 23 are suspended at intervals in the conveying direction of the primary processed material 2.

[0084] The number of sealing curtains 23 in the switching section 14 is preferably 2 to 50, more preferably 2 to 30, and even more preferably 5 to 20. If the number of sealing curtains 23 is above or below the lower limit of the above range, leakage of thermal decomposition gases and inactive gases from the primary processing section 13 to the secondary processing section 15, as well as leakage of oxidizing gases and oxygen-containing gases from the secondary processing section 15 to the primary processing section 13, can be sufficiently suppressed. If the number of sealing curtains 22 is below or below the upper limit of the above range, the primary processed material 2 can easily pass through the switching section 14.

[0085] The details and preferred method of the sealing curtain 23 are the same as those of the sealing curtain 22 in the inlet-side sealing chamber 12.

[0086] The secondary processing unit 15 is a region for obtaining a heat-treated product 3 by heat treatment under an oxidizing atmosphere while conveying the primary processed product 2 with an annular belt 21. An oxygen-containing gas inlet (not shown) is formed on the upper part of the secondary processing unit 15 for introducing oxygen-containing gas supplied from the second gas supply unit (not shown) into the secondary processing unit 15.

[0087] Inside the secondary processing unit 15, a muffle furnace 27 is sandwiched, which is equipped with an annular belt 21 for conveying the primary processed material 2. A pair of electric heaters 29 are provided in the conveying direction of the solar panel 1. Figure 2 ).

[0088] In the secondary processing unit 15, the primary processed product 2 is subjected to heat treatment, and the carbides of the resin such as the sealing material remaining in the primary processed product 2 are oxidized. As a result, the heat-treated product 3 is obtained in the secondary processing unit 15.

[0089] An exhaust port (not shown) is formed at the upper part of the secondary processing section 15. This exhaust port is used to discharge oxidizing gases generated by the oxidation of the carbides of the resin remaining in the primary processing material 2, such as sealing materials, from the secondary processing section 15 along with oxygen-containing gases. From the viewpoint of preventing the leakage of inactive gases and thermal decomposition gases from the primary processing section 13 to the secondary processing section 15, the exhaust port is preferably formed near the switching section 14. The oxidizing gases referred to here include, for example, carbon dioxide gas, water vapor, nitrogen oxides, sulfur oxides, and their incomplete combustion products, but are not limited to these.

[0090] Air-cooled chamber 16 and cooling chamber 17 are areas used for cooling the heated material 3. Cooling pipes (not shown) are installed in cooling chamber 17 to allow cooling water to flow.

[0091] The outlet-side sealing chamber 18 is an area used to suppress the intrusion of external gas into the cooling chamber 17, the air-cooled chamber 16 and the secondary treatment section 15, as well as the leakage of oxygen-containing gas and oxidizing gas from the secondary treatment section 15, the air-cooled chamber 16 and the cooling chamber 17.

[0092] An oxygen-containing gas inlet (not shown) is formed in the upper part of the outlet-side sealing chamber 18. This oxygen-containing gas inlet is used to introduce oxygen-containing gas supplied from the second gas supply unit (not shown) into the outlet-side sealing chamber 18.

[0093] In the outlet-side sealing chamber 18, multiple flexible sealing curtains 24 are suspended at intervals along the conveying direction of the heat-treated material 3, which cross the conveying direction of the heat-treated material 3 and are in contact with the annular belt 21.

[0094] The number of sealing curtains 24 in the outlet-side sealing chamber 18 is preferably 2 to 100, more preferably 10 to 60, and even more preferably 20 to 40.

[0095] If the number of sealing curtains 24 is above the lower limit of the above range, the intrusion of external gas into the cooling chamber 17 and the secondary processing section 15, as well as the leakage of oxygen-containing gas and oxidizing gas from the secondary processing section 15 and the cooling chamber 17, can be sufficiently suppressed. If the number of sealing curtains 24 is below the upper limit of the above range, the heat-treated material 3 can easily pass through the outlet-side sealing chamber 18.

[0096] The details and preferred method of the sealing curtain 24 are the same as those of the sealing curtain 22 in the inlet-side sealing chamber 12.

[0097] In one example, an opening adjustment plate for adjusting the opening of the passage of the heating furnace 20 (the outlet of the outlet-side sealing chamber 18) can also be provided in the outlet-side sealing chamber 18, downstream of the sealing curtain 24.

[0098] An outlet 19a is formed in the outlet-side exhaust chamber 19 for removing the heat-treated material 3 from the heating furnace 20. The outlet-side exhaust chamber 19 is a region for discharging external gas flowing in from the outlet 19a together with oxygen-containing gas and oxidizing gas from the outlet-side sealing chamber 18.

[0099] In one example, an opening adjustment plate for adjusting the opening of the passage (outlet 19a) of the heating furnace 20 can also be provided at the outlet 19a.

[0100] An exhaust port 19b is formed at the upper part of the exhaust chamber 19 on the export port side. The exhaust port 19b is used to discharge the external gas flowing in from the export port 19a together with the oxygen-containing gas and oxidizing gas from the export port side sealing chamber 18. One end of the exhaust pipe 72 is connected to the exhaust port 19b.

[0101] In one example, an opening adjustment unit for adjusting the opening degree can also be provided at the exhaust port 19b. An opening adjustment plate can be cited as an example of such an opening adjustment unit.

[0102] The continuous heating device 100 includes a combustion chamber 40 for burning the pyrolysis gases generated during the heat treatment and decomposition of the resin in the solar panel 1 in the primary processing unit 13. A pyrolysis gas supply pipe 61 for supplying the pyrolysis gases generated in the primary processing unit 13, an LPG supply pipe 63 for supplying LPG to the LPG tank 64, and an air supply pipe 62 for supplying air are connected to the combustion chamber 40. Additionally, an exhaust pipe 51 is connected to the combustion chamber 40 to discharge the exhaust gases generated during the combustion of the pyrolysis gases. The exhaust pipe 51 is connected to a first reheating line 811 and a second reheating line 821.

[0103] In the combustion chamber 40, the pyrolysis gas supplied from the primary treatment section 13 through the pyrolysis gas supply pipe 61 mixes with air and burns. The exhaust gas generated after the pyrolysis gas generated in the primary treatment section 13 is discharged out of the combustion chamber 40 through the exhaust pipe 51 and used for heating the primary treatment section 13 and the secondary treatment section 15.

[0104] The exhaust gas discharged from the combustion chamber 40 flows within the first reheating line 811 and the second reheating line 821, respectively. The exhaust gas discharged from the combustion chamber 40 is at a high temperature, so its thermal energy can be utilized by the first heat exchanger 31 and the second heat exchanger 32, which are respectively connected to the first reheating line 811 and the second reheating line 821.

[0105] The first heat exchanger 31 and the second heat exchanger 32 respectively utilize the heat energy generated by the combustion of the thermal decomposition gases produced during the heat treatment and decomposition of the sealing material of the solar panel in the primary processing unit 13. In the continuous heating device 100, the thermal decomposition gases produced during the heat treatment and decomposition of the sealing material of the solar panel in the primary processing unit 13 are converted into high-temperature exhaust gases generated by the combustion reaction in the combustion chamber 40. Therefore, the first heat exchanger 31 and the second heat exchanger 32 can respectively utilize the heat energy of the exhaust gases generated after the thermal decomposition gases are combusted.

[0106] The first heat exchanger 31 uses the heat energy of the exhaust gas generated after the combustion of the pyrolysis gases to heat the primary treatment section 13. The second heat exchanger 32 uses the heat energy of the exhaust gas generated after the combustion of the pyrolysis gases to heat the secondary treatment section 15.

[0107] Here, as Figure 2 As shown, a first heat exchanger 31 and a second heat exchanger 32 are disposed in the space between the muffle furnace 27 and the outer wall 28. Additionally, as... Figure 1 , Figure 2as well as Figure 3 As shown, heat exchanger 31 is arranged near the outer wall 28 of the primary processing unit 13 along the conveying direction of the annular belt 21. Additionally, heat exchanger 32 is arranged near the outer wall 28 of the secondary processing unit 15 along the conveying direction of the annular belt 21.

[0108] The heating of the exhaust gas discharged from the combustion chamber 40 by the primary treatment unit 13 is carried out as follows. For example... Figure 1 and Figure 3 As shown, exhaust gas is supplied from the first reheating line 811 to the first heat exchanger 31. The first heat exchanger 31 uses the heat energy of the exhaust gas supplied from the first reheating line 811 to heat the primary treatment section 13. The exhaust gas passing through the first heat exchanger 31 flows sequentially through the exhaust pipe 813 and the exhaust pipe 73, and is supplied to the scrubber 91.

[0109] The heating of the exhaust gas discharged from the combustion chamber 40 in the secondary treatment section 15 is performed as follows. For example... Figure 1 and Figure 3 As shown, exhaust gas is supplied from the second reheating line 821 to the second heat exchanger 32. The second heat exchanger 32 uses the heat energy of the exhaust gas supplied from the second reheating line 821 to heat the secondary treatment section 15. The exhaust gas passing through the second heat exchanger 32 flows sequentially through the exhaust pipe 823 and the exhaust pipe 73, and is supplied to the scrubber 91.

[0110] There are no particular limitations on the first heat exchanger 31 and the second heat exchanger 32. In terms of suppressing corrosion on the outer side of the muffle furnace 27 and the inner side of the outer wall 28, indirect heat exchangers are preferred. There are no particular limitations on the indirect heat exchanger, and examples include multi-tube heat exchangers, serpentine heat exchangers, and heating walls.

[0111] The exhaust gas discharged from combustion chamber 40 sometimes contains fluorine, unburned gases, NOx, etc., which may exhibit corrosiveness. In particular, depending on the type of resin in the sealing material of the solar panels, the airflow within combustion chamber 40, and temperature conditions, unexpected corrosive gases such as fluorine, unburned gases, and NOx may remain. If these corrosive gases are directly supplied to the space between the muffle furnace 27 and the outer wall 28, the wall surface may corrode. This would necessitate complex maintenance, including the replacement and cleaning of the entire heating furnace.

[0112] Therefore, according to the indirect heat exchanger, by allowing two fluids of different temperatures to flow in a space divided by its internal walls, heat can be transferred from the high-temperature fluid to the low-temperature fluid via heat transfer to the walls, heat conduction through the walls, and heat transfer from the high-temperature fluid to the low-temperature fluid via the walls themselves. Thus, the exhaust gas discharged from the combustion chamber 40 can be heated in both the primary treatment section 13 and the secondary treatment section 15 through heat exchange, without directly supplying it to the space between the muffle furnace 27 and the outer wall 28. According to the indirect heat exchanger, since the exhaust gas passes through its interior, the effects of corrosive gases can be confined to the indirect heat exchanger itself. Even if corrosion occurs, only the indirect heat exchanger needs to be selectively replaced. Furthermore, corrosion on the outer side of the muffle furnace 27 and the inner side of the outer wall 28 constituting the heating furnace 20 can be prevented. As a result, maintenance under corrosive gas conditions becomes easier with the indirect heat exchanger.

[0113] exist Figure 1 In the example shown, the pyrolysis gas supply pipe 61 and the air supply pipe 62 supply the pyrolysis gas and air to the combustion chamber 40 independently, respectively. However, in other examples, the pyrolysis gas and air may be pre-mixed in order to improve combustion efficiency and reduce corrosive gases before the mixed gas is supplied to the combustion chamber 40.

[0114] When the pyrolysis gas and air are premixed, it can also be replaced Figure 1 The pyrolysis gas supply pipe 61 and air supply pipe 62 shown are, for example, parallel pipes in which pyrolysis gas and air are premixed. These parallel pipes have at least a portion of pyrolysis gas and air supply pipes arranged in parallel with each other. The portion of the parallel pipe in which the pyrolysis gas and air supply pipes are arranged in parallel has an opening for the internal flow of pyrolysis gas and air. Therefore, the mixture of pyrolysis gas and air can be premixed and supplied to the combustion chamber 40.

[0115] There are no particular limitations on the parallel tube configuration. Examples include a double tube in which the pyrolysis gas supply tube and the air supply tube are arranged in concentric circles, and a square tube in which the pyrolysis gas supply tube and the air supply tube are arranged adjacent to each other.

[0116] Scrubber 91 is disposed downstream of exhaust pipes 71, 72, 813, 823, and 73. Scrubber 91 is used to remove harmful substances from the gas before it is discharged to the outside from the various areas within the continuous heating device 100.

[0117] The first gas supply unit (not shown) supplies inert gases to the primary processing section 13, the inlet-side sealing chamber 12, and the switching section 14 within the heating furnace 20. Examples of gas supply sources for the first gas supply unit include membrane-separated nitrogen generators, inert gas cylinders, and inert gas canisters. Examples of inert gases include nitrogen, argon, helium, xenon, carbon dioxide, and superheated steam. From an economic point of view, nitrogen is preferred.

[0118] The second gas supply unit (not shown) supplies oxygen-containing gas to the secondary processing section 15 and the outlet-side sealing chamber 18 within the heating furnace 20. Examples of gas supply sources for the second gas supply unit include oxygen-containing gas cylinders and oxygen-containing gas tanks. Examples of oxygen-containing gases include air and oxygen. From an economic point of view, air is preferred.

[0119] (Method for manufacturing heat-treated products)

[0120] The manufacturing method of the heat-treated product 3 using the continuous heating device 100 will be described.

[0121] First, inert gas is continuously supplied to the inlet-side sealing chamber 12 and the switching section 14. Additionally, oxygen-containing gas is continuously supplied to the outlet-side sealing chamber 18. In the muffle furnace of the primary processing section 13, a non-oxidizing atmosphere is prepared by continuously supplying inert gas. In the muffle furnace of the secondary processing section 15, an oxidizing atmosphere is prepared by continuously supplying oxygen-containing gas.

[0122] Examples of inactive gases supplied to the primary processing unit 13 include nitrogen, argon, helium, xenon, carbon dioxide, and superheated steam. From an economic point of view, nitrogen is preferred.

[0123] As the oxygen-containing gas supplied to the secondary processing unit 15, examples include air and oxygen. From an economic point of view, air is preferred.

[0124] Examples of inactive gases supplied for sealing into the inlet-side sealing chamber 12 and the outlet-side sealing chamber 18 include nitrogen, argon, helium, xenon, carbon dioxide, and superheated steam. From an economic point of view, nitrogen is preferred. Furthermore, from the perspective of reducing the amount of gas used through volume expansion, the inactive gas is preferably heated.

[0125] By driving an exhaust fan (not shown), external gas flowing in from the inlet 11a of the furnace 20, along with inert gas and pyrolysis gas from the inlet-side sealing chamber 12, is constantly discharged from the exhaust port 11b. To suppress leakage of inert gas and pyrolysis gas from the furnace 20, an opening adjustment plate can also be used to adjust the amount of external gas flowing in from the inlet 11a of the furnace 20.

[0126] Additionally, the external gas flowing in from the outlet 19a of the furnace 20, together with the oxygen-containing gas and oxidizing gas from the outlet-side sealing chamber 18, is always discharged from the exhaust port 19b. In one example, in order to suppress the leakage of oxygen-containing gas and oxidizing gas from the furnace 20, an opening adjustment plate can also be used to adjust the amount of external gas flowing in from the outlet 19a of the furnace 20.

[0127] The opening of exhaust port 11b and exhaust port 19b can also be adjusted as needed.

[0128] A solar panel 1 is mounted on an annular belt 21 that moves from the upstream side of the furnace 20 through the furnace 20 to the downstream side of the furnace 20. The solar panel 1 is carried in from the inlet 11a of the furnace 20 by the annular belt 21 and transported within the furnace 20.

[0129] Inside the inlet-side sealed chamber 12, the solar panel 1 is conveyed while the sealing curtain 22 is pushed upwards. The opening of the inlet of the inlet-side sealed chamber 12 can also be adjusted using an opening adjustment plate as needed.

[0130] Within the primary processing unit 13, the solar panel 1 is conveyed while undergoing heat treatment in a non-oxidizing atmosphere. This thermally decomposes the resin of the sealing material contained in the solar panel 1 to obtain the primary processed product 2. From the perspective of suppressing the formation of detonating gases, the oxygen concentration within the primary processing unit 13 is preferably 3.0% by volume or less, more preferably 1.0% by volume or less, and even more preferably 0.1% by volume or less.

[0131] The atmosphere temperature within the primary processing unit 13 is set to, for example, 300~550°C, and the heating time is appropriately set within the range of 10~180 minutes, depending on the heating temperature. The heating temperature can also be set in multiple stages. For example, the first stage can be set to 300~400°C to decompose and vaporize the acetic acid portion of EVA, followed by a second stage set to 400~550°C to decompose and vaporize the polyethylene portion, which is the main chain of EVA. This promotes the decomposition and vaporization of EVA and inhibits the formation of residues such as carbides.

[0132] Inside the switching section 14, the primary processing item 2 is conveyed from the primary processing section 13 to the secondary processing section 15 while the sealing curtain 23 is pushed up.

[0133] Within the secondary processing section 15, the primary processed product 2 is conveyed while undergoing heat treatment in an oxidizing atmosphere. This oxidizes the carbides of the resin remaining in the primary processed product 2, such as sealing materials, resulting in a heat-treated product 3. The oxygen concentration within the secondary processing section 15 is preferably 80% by volume or less, more preferably 50% by volume or less, and even more preferably 25% by volume or less. Furthermore, considering the promotion of oxidation of the carbides (coal) of the resin remaining in the primary processed product 2, it is preferably 5% by volume or more, more preferably 10% by volume or more, and even more preferably 15% by volume or more.

[0134] The ambient temperature inside the secondary processing unit 15 is set to, for example, 300~500°C, and the heating time is appropriately set within the range of 10~180 minutes, depending on the heating temperature.

[0135] In the air-cooled chamber 16, the heat-treated object 3 is slowly cooled to prevent the glass from cracking due to sudden cooling. Then, in the cooling chamber 17, which is supplied with cooling water, the heat-treated object 3 is cooled to a temperature that can be handled by the operator, for example, below 100°C.

[0136] Inside the outlet-side sealing chamber 18, the heated material 3 is conveyed while pushing up the sealing curtain 24. The opening of the outlet of the outlet-side sealing chamber 18 can also be adjusted using an opening adjustment plate as needed.

[0137] The heat-treated material 3, conveyed within the heating furnace 20, is removed from the outlet 19a of the heating furnace 20 using an annular belt 21. The heat-treated material 3 removed from the heating furnace 20 mainly consists of battery cells, glass substrates, etc. Sometimes trace amounts of coal may adhere to it, but the amount is reduced to, for example, below 100 ppm.

[0138] (Mechanism of action)

[0139] In the continuous heating apparatus 100 described above, since a heating furnace 20 is provided that heat-treated material 3 is obtained by heat-treating the solar panel 1 while conveying it, the heat-treated material 3 can be obtained by continuously heat-treating the solar panel 1. Therefore, compared with batch processing, the processing capacity per unit time can be increased.

[0140] Furthermore, the primary processing unit 13 and the secondary processing unit 15 utilize the heat energy generated by the combustion of thermal decomposition gases produced when the sealing material of the solar panel 1 is decomposed by heat treatment in the primary processing unit 13.

[0141] In particular, the thermal decomposition gas produced in the primary processing unit 13 contains more combustible gas than the oxidizing gas produced in the secondary processing unit 15. According to the continuous heating device 100, the heat energy generated by the combustion of the thermal decomposition gas containing more combustible gas produced in the primary processing unit 13 can be used as an auxiliary for heating the primary processing unit 13 and the secondary processing unit 15.

[0142] More specifically, the thermal decomposition gas generated when the sealing material of the solar panel is decomposed by heat treatment in the primary processing unit 13 is converted into high-temperature exhaust gas generated by the combustion reaction in the combustion chamber 40, and the thermal energy is utilized by the first heat exchanger 31 and the second heat exchanger 32 respectively.

[0143] According to the continuous heating device 100 with the characteristic configuration described above, the heat energy generated by the combustion of thermal decomposition gas can be utilized in each heat treatment in the primary processing section 13 and the secondary processing section 15, so the thermal efficiency in the heat treatment of solar panels can be improved and the energy cost for heating the primary processing section 13 and the secondary processing section 15 can be reduced.

[0144] Furthermore, according to this embodiment, since the thermal efficiency in the heat treatment of the solar panel is improved, the amount of coal adhering from the resin residue can be reduced.

[0145] In one example, the amount of coal adhering to the heat-treated product can be 100 ppm or less. Preferably, the amount of coal adhering to the heat-treated product is 70 ppm or less, more preferably 50 ppm or less, and even more preferably 10 ppm or less. The lower limit of the amount of coal adhering to the heat-treated product is not particularly limited; for example, it can be 0.1 ppm, 1 ppm, etc.

[0146] exist Figure 1 In the example of the continuous heating apparatus 100 shown, both the primary processing unit 13 and the secondary processing unit 15 utilize the heat energy generated by the combustion of thermal decomposition gases produced when the resin of the solar panel 1 is decomposed by heat treatment in the primary processing unit 13. However, in other examples of continuous heating apparatuses, either the primary processing unit 13 or the secondary processing unit 15 may utilize the heat energy generated by the combustion of thermal decomposition gases produced when the resin of the solar panel 1 is decomposed by heat treatment in the primary processing unit 13.

[0147] Furthermore, in the continuous heating device 100, a sealing curtain 22 is suspended in the inlet-side sealed chamber 12 upstream of the primary processing section 13, where the solar panel 1 is heated, extending across the conveying direction of the solar panel 1 and hanging down to its length in contact with the annular belt 21. Therefore, external gases entering the inlet-side sealed chamber 12, as well as inactive gases and thermally decomposed gases from the primary processing section 13, are difficult to pass through the inlet-side sealed chamber 12. Additionally, a sealing curtain 24 is also suspended in the outlet-side sealed chamber 18 downstream of the secondary processing section 15, extending across the conveying direction of the heated material 3 and hanging down to its length in contact with the annular belt 21. Therefore, external gases entering the outlet-side sealed chamber 18, as well as oxygen-containing gases and oxidizing gases from the primary processing section 13 and the cooling chamber 17, are difficult to pass through the outlet-side sealed chamber 18.

[0148] The sealing curtain 22 inside the inlet-side sealing chamber 12 is flexible. Therefore, as Figure 5 As shown, when the solar panel 1 passes through the inlet-side sealing chamber 12, the sealing curtain 22 is pushed upward in a flexed state. At this time, the sealing curtain 22 is pressed against the solar panel 1, as... Figure 6 as well as Figure 7 As shown, the sealing curtain 22 is in close contact with the surface of the solar panel 1, following the thickness and shape of the upper surface. Therefore, the gap between the sealing curtain 22 and the upper surface of the solar panel 1 is minimized. Consequently, external gases entering the inlet-side sealing chamber 12, as well as inactive gases and thermally decomposed gases from the primary processing unit 13, are also difficult to pass through the inlet-side sealing chamber 12 when the solar panel 1 passes through it.

[0149] The sealing curtain 23 within the switching section 14 is also flexible. Therefore, for the same reasons as the sealing curtain 22, the gap between the sealing curtain 23 and the primary processed product 2 is minimized. Consequently, inactive gases and thermally decomposed gases from the primary processed section 13 that have entered the switching section 14 are also less likely to enter the secondary processed section 15 when the primary processed product 2 passes through the switching section 14. Furthermore, oxygen-containing gases and thermally decomposed gases from the secondary processed section 15 that have entered the switching section 14 are also less likely to enter the primary processed section 13 when the primary processed product 2 passes through the switching section 14.

[0150] The sealing curtain 24 inside the outlet-side sealing chamber 18 is also flexible. Therefore, for the same reason as the sealing curtain 22, the gap between the sealing curtain 24 and the heat-treated material 3 is minimized. As a result, external gases that intrude into the outlet-side sealing chamber 18, as well as oxygen-containing gases and oxidizing gases from the secondary processing unit 15 and the cooling chamber 17, have difficulty passing through the outlet-side sealing chamber 18 when the heat-treated material 3 passes through it.

[0151] In this way, the intrusion of external gases into the primary processing section 13 and the secondary processing section 15 can be suppressed in the continuous heating device 100. Therefore, the oxygen concentration in the primary processing section 13 is less likely to rise excessively. In addition, the solar panel 1 can be continuously heat-treated to obtain the heat-treated product 3 while maintaining a non-oxidizing atmosphere in the primary processing section 13. As a result, the formation of detonating gases can be suppressed. Furthermore, the leakage of inactive gases and thermal decomposition gases from the heating furnace 20 can be suppressed.

[0152] In the continuous heating apparatus 100 described above, multiple sealing curtains 22 are suspended at intervals in the transport direction of the solar panel 1 within the inlet-side sealed chamber 12. This makes it more difficult for external gases and inactive gases and thermally decomposed gases from the primary processing section 13 to enter the inlet-side sealed chamber 12. Similarly, multiple sealing curtains 24 are suspended at intervals in the transport direction of the heated material 3 within the outlet-side sealed chamber 18. This further hinders the entry of external gases and oxygen-containing gases and oxidizing gases from the secondary processing section 15 and the cooling chamber 17 into the outlet-side sealed chamber 18. Therefore, the intrusion of external gases into the primary processing section 13 and the secondary processing section 15, as well as the leakage of oxygen-containing gases and oxidizing gases from the heating furnace 20, can be effectively suppressed.

[0153] In the continuous heating device 100 described above, the sealing curtain 22 inside the inlet-side sealing chamber 12 is composed of multiple strips 22A arranged without gaps in the direction traversing the conveying direction of the solar panel 1; that is, the sealing curtain 22 is finely divided. Therefore, as Figure 6 and Figure 7As shown, only the minimum width of the strip 22A is pushed upwards in the direction corresponding to the transport direction of the solar panel 1. Therefore, the difference between the total width of the strip 22A pushed upwards by the solar panel 1 and the width of the solar panel 1 can be minimized as much as possible, and the gap between the side of the solar panel 1 and the strip 22A formed on both sides of the solar panel 1 in the direction corresponding to the transport direction of the solar panel 1 can be minimized as much as possible. Therefore, it is more difficult for external gases and inactive gases and thermally decomposed gases from the primary processing unit 13 to enter the inlet-side sealing chamber 12. In addition, the sealing curtain 24 in the outlet-side sealing chamber 18 is also composed of multiple strips (not shown) arranged without gaps in the direction corresponding to the transport direction of the heated material 3. Therefore, for the same reason as the sealing curtain 22, it is more difficult for external gases and oxygen-containing gases and oxidizing gases from the secondary processing unit 15 and the cooling chamber 17 to enter the outlet-side sealing chamber 18. Therefore, it is possible to effectively suppress the intrusion of external gas into the primary processing unit 13 and the leakage of oxygen-containing gas and oxidizing gas from the heating furnace 20.

[0154] [Recycling system for components of solar panels]

[0155] The recycling system for components of solar panels includes a continuous heating device and a sorting device for separating glass raw materials and valuable metal contents from the heat-treated material obtained by the continuous heating device. Details and preferred embodiments of the continuous heating device are described above. Hereinafter, embodiments of the sorting device will be described in detail.

[0156] Figure 8 This is a schematic diagram illustrating an example of a recycling system for the components of a solar panel. The recycling system 200 includes a dismantling processing unit 211, a heating processing unit 231, a screening processing unit 241, a screening recycling unit 242, an air-powered sorting unit 251, a light product recycling unit 252, an air-shaking sorting unit 261, an exhaust recycling unit 621, a retained product recycling unit 622, and a glass recycling unit 623.

[0157] The disassembly processing unit 211 performs pre-processing such as disassembling the aluminum frame of the solar panel and removing the backsheet, terminal box, and cables. Using the disassembly processing unit 211, the aluminum frame, backsheet, terminal box, and cables can be removed from the solar panel as needed. Then, the internal structure of the solar panel is processed sequentially.

[0158] The glass substrate of the solar panel is preferably made of tempered glass. This is because it can be recycled as fine granular glass after heat treatment, making it easy to process using a sorting device. Alternatively, the glass of the solar panel may be cracked before heat treatment.

[0159] The heat treatment unit 231 manufactures a heat-treated product by performing heat treatment using the continuous heating apparatus of the present invention. By performing heat treatment using the continuous heating apparatus of the present invention, resin from the sealing material of the solar panel can be removed.

[0160] When using the continuous heating device 100, the primary processing performed by the primary processing unit 13 and the secondary processing performed by the secondary processing unit 15 are sequentially performed in the heat treatment unit 231.

[0161] The details and preferred methods of primary and secondary processing are as described above.

[0162] The screening and processing unit 241 screens the heat-treated material obtained from the continuous heating device into a first valuable metal containing battery cells and copper wire and a first glass raw material.

[0163] By screening by the screening processing unit 241, the oversize and undersize materials can be separated. The oversize material is recycled to the oversize recycling unit 242. The oversize material contains a first valuable metal containing battery cells and copper wire. Examples of oversize materials include linear materials such as copper wire, relatively large materials such as battery cells, and materials formed by their winding.

[0164] The undersize material is then processed by the air separation unit 251. The undersize material can be crushed as needed before being processed by the air separation unit 251. The undersize material contains the first glass raw material.

[0165] The screening processing unit 241 has sieves. The sieves of the screening processing unit 241 can be one or multiple.

[0166] The mesh size of the sieve in the screening processing unit 241 is preferably 1 to 100 mm. In the case of multiple sieves, screening can be performed while changing the mesh size of the sieves in stages.

[0167] For example, a first screening section using a first sieve with a mesh size of 5mm or larger, 8mm or larger, 10mm or larger, 15mm or larger, or 20mm or larger, and a second screening section using a second sieve with a mesh size smaller than the first sieve, such as 15mm or smaller, 10mm or smaller, 8mm or smaller, 5mm or smaller, or 3mm or smaller. The difference in mesh size between the first and second sieves can also be set to 1mm or larger, or 3mm or larger, or 5mm or larger, etc.

[0168] The mesh size of the sieve can be up to 80mm or less, or up to 60mm. The opening shape of the sieve used for screening can also be round or polygonal. Alternatively, a screening machine can be used.

[0169] The wind-powered sorting unit 251 separates the first glass raw material, after being screened by the screening unit 241, into a second valuable metal containing solar cells and a second glass raw material through wind-powered sorting. The second valuable metal containing solar cells is recycled as a light product to the light product recycling unit 252. The second glass raw material is processed as a heavy product in the subsequent air-shaking table sorting unit 261.

[0170] Wind separation is a type of gravity separation technology. Gravity separation is a separation technology that uses the difference in specific gravity between a target substance and other substances to separate them. As wind separation devices, vertical wind separators, sawtooth separators, horizontal flow separators, inertial force linear separators, and inertial force curved separators can be used.

[0171] For example, Japanese Patent Application Publication No. 2023-89446 can also be used. Figure 9 The vertical wind separator shown is an example of a wind separator. According to the vertical wind separator, by blowing an upward flow from below onto a longitudinal column, particles with low settling velocity and low density can be moved upwards and recovered as light products, while particles with high settling velocity and high density can be moved downwards and recovered as heavy products.

[0172] Light products from wind separation include solar cell fragments. Heavy products from wind separation include concentrates of coarse-grained glass from solar cells. In isotropic glass from cover glass and the like, small particles are easily grouped into the light products. On the other hand, solar cell fragments are considered to be flat particles, easily absorbing airflow over a wide area; therefore, larger particles are more easily grouped into the light products. Larger particles are easier to separate into light and heavy products, thus reducing the need for excessive crushing before wind separation. Metal recycling is possible by refining the second valuable metal content of the solar cell fragments containing light products.

[0173] The wind speed in wind separation can be set to 4~15m / s, and the air volume can be set to 20~70L / min. As a suitable device for wind separation, the Harada Sangyo L750 SRM wind separator can be cited as an example.

[0174] The air shaker sorting unit 261 uses an air shaker to separate the third glass raw material from the heavy product obtained by the wind-powered sorting unit 251. The air shaker sorting unit 261 can separate the third glass raw material into (i) the third glass raw material containing high-purity glass, (ii) retained light products such as single-edged products containing low-purity glass and copper wire sources, and (iii) discharged light products containing copper wire sources and battery cell sources.

[0175] The valuable metal contents are recovered to the discharge recovery unit 621 and the retained material recovery unit 622 via the air shaking table sorting unit 261. In addition, the third glass raw material is recovered to the glass recovery unit 623.

[0176] Regarding the air shaker sorting unit 261, for example, the one described in Patent Document 1 can also be used. Figure 10 The single-axis air-shaking table separator shown is described. According to this air-shaking table separator, vibration is applied to a table surface that is slightly angled from the horizontal direction, and air is supplied to the table surface from below in a direction perpendicular to the table surface. High-density particles are almost unaffected by the airflow and move downwards within the powder layer, concentrating near the protrusions on the table surface. Their downward movement is suppressed at the protrusions, and they move upwards on the table surface due to the vibration, being recovered as heavy products. On the other hand, low-density particles are affected by the airflow and move upwards within the powder layer, moving downwards along the inclination of the table surface, being recovered as light products.

[0177] In air-shaking table sorting, materials can be classified into various categories, such as materials discharged from the air-shaking table's outlet and objects retained on the air-shaking table. (Referring to Patent Document 1...) Figure 10 Taking an air shaker as an example, light products, mainly copper wires and battery cells, are discharged from below the table. Heavy products, mainly glass, are discharged from above the table. Additionally, materials that are difficult to move during air shaker operation are sometimes collected as residue left on the table. Light products such as copper wires are separated from this residue on the upper side of the powder layer.

[0178] For example, Harada Sangyo's SRM 296P-72N air shaker can be cited as an example. In order to separate light products and heavy products with higher precision, further separation can be carried out by air separation, air shaker separation, screening, etc.

[0179] The recycling system for the constituent components of the solar panel according to the present invention enables the glass purity of the sorted third glass raw material to be 99.99% or higher. The glass purity of the sorted third glass raw material is preferably 99.995% or higher, more preferably 99.999% or higher, and even more preferably 99.9995% or higher. The upper limit of the glass purity of the sorted third glass raw material is not particularly limited, and for example, it can be 99.9999%, 99.9998%, etc.

[0180] The recycling rate of glass raw materials contained in the heat-treated product is preferably 85% or more, more preferably 90% or more, and even more preferably 93% or more.

[0181] The recycling rate of glass raw materials contained in the heat-treated product is calculated by the following formula.

[0182] The recycling rate of glass raw materials contained in the heat-treated product = weight of recycled glass raw materials / weight of glass raw materials contained in the heat-treated product

[0183] The copper wire contained in the heat-treated product can be recycled through metal refining of the first valuable metal content. The recycling rate of the copper wire is preferably 90% or more, more preferably 95% or more, and even more preferably 99% or more.

[0184] The recycling rate of copper wire contained in the heat-treated product is calculated by the following formula.

[0185] The recycling rate of copper wire in the heat-treated product = weight of recycled copper wire / weight of copper wire in the heat-treated product

[0186] The battery cells contained in the heat-treated product can be recycled through metal refining of the first valuable metal content and the second valuable metal content. The recycling rate of the battery cells is preferably 90% or more, more preferably 95% or more, and even more preferably 99% or more.

[0187] The recycling rate of the battery cells contained in the heat-treated material is calculated by the following formula.

[0188] The recycling rate of solar cells contained in the heat-treated product = weight of recycled solar cells / weight of solar cells contained in the heat-treated product

[0189] The above describes several embodiments, but the present invention is not limited to the embodiments disclosed in this specification, and can be implemented by appropriate modifications without changing its spirit. The embodiments disclosed in this specification can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention.

[0190] For example, Figure 9 This is a schematic diagram illustrating another example of a recycling system for the components of a solar panel. Recycling system 201 is... Figure 8 A variation of the recycling system 200 is shown. As with recycling system 201, the order of the disassembly processing unit 211 and the heat treatment unit 231 can be reversed. That is, the disassembly processing can be performed after heat treatment using the continuous heating device of the present invention. The resin in the back plate, terminal box, etc., is removed by the heat treatment.

[0191] Example

[0192] The embodiments are described in more detail below, but the present invention is not limited to the following description.

[0193] [Example 1]

[0194] The solar panel is processed using a continuous heating device 100 to obtain a heat-treated product. Then, the aluminum frame is removed. In the first treatment, the product is heated for 7 minutes at a temperature gradually increasing from room temperature to 500°C under a nitrogen atmosphere, and then heated to 500°C for 16 minutes. The oxygen concentration in the first treatment section 13 is controlled at 3% by volume. In the second treatment, the product is heated to 500°C for 16 minutes under an oxidizing atmosphere. The oxygen concentration in the second treatment section 15 is controlled at 21% by volume.

[0195] Next, use Figure 8 The recycling system 200 shown sorts 273.6 kg of heat-treated material (3.4 kg of copper wire, 13 kg of solar cells, and 255.5 kg of glass raw materials). As a result of the sorting process, 17 kg of a first valuable metal containing 62.6% copper wire and solar cells (the remainder being glass), 14.7 kg of a second valuable metal containing 39.3% solar cells (the remainder being glass), and 239.5 kg of a third glass raw material with a purity of 99.9997% (the remainder being solar cells) were recovered. The recycling rates were 100% for copper wire, 99.5% for solar cells, and 93.7% for glass raw materials.

[0196] [Comparative Example 1]

[0197] Except for not operating the secondary processing unit 15 and performing heat treatment only using the primary processing unit 13, the solar panel is heat-treated using the continuous heating device 100 under the same conditions as in Example 1.

[0198] If correct Figure 10 and Figure 11 As the comparison shows, in Example 1, the amount of coal adhering to the glass fragments was reduced compared to Comparative Example 1.

[0199] Industrial utilization potential

[0200] According to the present invention, the thermal efficiency in the heat treatment of solar panels can be improved, energy costs can be reduced, and the quality of valuables recovered from solar panels can be improved.

[0201] Explanation of reference numerals in the attached figures

[0202] 1: Solar panel, 2: Primary processed material, 3: Heated material, 13: Primary processing unit, 14: Switching unit, 15: Secondary processing unit, 20: Heating furnace, 21: Annular belt.

Claims

1. A continuous heating device comprising a heating furnace, wherein a heated object is obtained by heat treatment while a solar panel is being conveyed via an annular belt. The heating furnace has the following features: The primary processing unit obtains a primary processed product by heat-treating the solar panels under a non-oxidizing atmosphere while conveying them via the annular belt. The secondary processing unit obtains the heat-treated product by heat-treating the primary processed product under an oxidizing atmosphere while conveying it via the annular belt. At least one of the primary processing unit and the secondary processing unit utilizes the heat energy generated by the combustion of thermal decomposition gases produced when the sealing material of the solar panel is decomposed by heat treatment in the primary processing unit.

2. The continuous heating device according to claim 1, wherein, A flexible sealing curtain that traverses the transport direction of the solar panel and contacts the annular belt is suspended in at least one location within the heating furnace.

3. The continuous heating device according to claim 2, wherein, The sealing curtain is suspended inside the heating furnace between the primary processing section and the secondary processing section.

4. The continuous heating device according to claim 2, wherein, The sealing curtain is suspended inside the heating furnace upstream of the primary processing unit.

5. The continuous heating device according to claim 2, wherein, The sealing curtain is suspended inside the heating furnace downstream of the secondary processing unit.

6. The continuous heating device according to claim 1, wherein, At least one of the primary processing unit and the secondary processing unit utilizes the thermal energy of the waste gas generated after the thermal decomposition gas is burned.

7. The continuous heating device according to claim 1, wherein, It further includes a combustion chamber for burning the thermal decomposition gases generated when the sealing material of the solar panel is decomposed by heat treatment in the primary processing section.

8. The continuous heating device according to claim 7, wherein, At least one of the primary treatment unit and the secondary treatment unit utilizes the thermal energy of the exhaust gas discharged from the combustion chamber.

9. The continuous heating device according to claim 1, wherein, A heat exchanger utilizing the heat energy generated by the combustion of the thermally decomposed gas is disposed in at least one of the primary processing unit and the secondary processing unit.

10. The continuous heating device according to claim 9, wherein, The heat exchanger utilizes the thermal energy of the exhaust gas produced after the thermal decomposition gas is burned.

11. The continuous heating device according to claim 9, wherein, The heating furnace has a muffle furnace that is surrounded in a manner that covers the annular belt and an outer wall that is surrounded in a manner that covers the muffle furnace, and the heat exchanger is disposed in the space between the muffle furnace and the outer wall.

12. The continuous heating device according to claim 9, wherein, The heat exchanger is an indirect heat exchanger.

13. The continuous heating device according to claim 11, wherein, An electric heater is disposed in the space between the muffle furnace and the outer wall.

14. The continuous heating device according to claim 1, wherein, The amount of coal adhering to the heat-treated material is less than 100 ppm.

15. A recycling system for components of a solar panel, comprising: The continuous heating device according to any one of claims 1 to 14, and The sorting device separates glass raw materials and valuable metal contents from the heat-treated material.

16. The recycling system for the constituent components of a solar panel according to claim 15, wherein, The sorting device has a screening process section, which screens the heat-treated material into a first valuable metal content containing battery cells and copper wire and a first glass raw material.

17. The recycling system for components of a solar panel according to claim 16, wherein, The sorting device further includes a wind-powered sorting section, which sorts the first glass raw material after being screened by the screening processing section into a second valuable metal containing battery cells and a second glass raw material by wind-powered sorting.

18. The recycling system for components of a solar panel according to claim 17, wherein, It further includes an air shaker sorting unit, which uses an air shaker to sort a third glass raw material from the second glass raw material.

19. The recycling system for the constituent components of a solar panel according to claim 18, wherein, The glass purity of the third glass raw material after sorting is above 99.99%.

20. The recycling system for components of a solar panel according to claim 15, wherein, The recycling rate of the glass raw materials contained in the heat-treated product is over 85%.

21. The recycling system for the constituent components of a solar panel according to claim 15, wherein, The recyclability of the battery cells contained in the heat-treated material is over 90%.

22. The recycling system for the constituent components of a solar panel according to claim 15, wherein, The copper wire contained in the heat-treated material has a recycling rate of over 90%.

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