Method for separating and recycling glass in photovoltaic module

Abstract

The invention relates to the technical field of photovoltaic module treatment, in particular to a method for separating and recycling glass in a photovoltaic module. The method for separating and recycling the glass in the photovoltaic module comprises the following steps: providing the photovoltaic module, and obtaining a laminated part of the photovoltaic module; wherein the laminated piece comprises glass, an adhesive film and a battery piece which are arranged in a laminated manner; breaking the glass on the laminated piece so as to form cracks on the glass and divide the glass into a plurality of blocks at the same time; soaking the laminated part with the cracks in a soaking solution so as to swell the adhesive film; and after soaking, separating the glass and the adhesive film in the laminated piece to obtain a plurality of glass blocks. The embodiment of the invention is suitable for separation treatment of the glass in the laminated piece, and large-area glass with controllable size can be recycled.

Description

Technical Field

[0001] The present application relates to the technical field of photovoltaic module processing, and in particular to a method for separating and recycling glass in photovoltaic modules. Background Art

[0002] In recent years, the installed capacity of photovoltaic modules has shown an exponential growth. After the photovoltaic modules have completed their service life or retired early, they need to be properly disposed of. Considering the potential economic benefits of photovoltaic module materials, it is necessary to dismantle and dispose of photovoltaic modules and recycle various materials to realize their reuse value. Photovoltaic modules contain aluminum frames, front glass, front film, battery cells, back film, back glass or backboard, and junction boxes. The disassembly and recycling of photovoltaic modules usually involves mechanical removal of aluminum frames and junction boxes, and the rest of the components are collectively referred to as photovoltaic laminates (hereinafter referred to as laminates). Among them, glass is recovered from laminates for remanufacturing and recycling, which can save glass raw materials and has high economic benefits.

[0003] At present, most of the laminates are crushed, ground and sorted by physical methods. The glass obtained by this method is almost granular and contains a lot of dust pollutants. The use of physical methods to obtain glass will cause secondary pollution, and the economic efficiency of granular broken glass is low. How to recycle large areas of glass needs to be solved urgently.

[0004] It should be noted that the above content is not necessarily prior art, nor is it intended to limit the scope of patent protection of this application. Summary of the invention

[0005] The embodiments of the present application provide a method for separating and recycling glass in a photovoltaic module to solve or alleviate one or more of the technical problems mentioned above.

[0006] The embodiment of the present application provides a method for separating and recycling glass in a photovoltaic module. The method for separating and recycling glass in a photovoltaic module comprises the following operations: Providing a photovoltaic module, obtaining a laminate of the photovoltaic module; Wherein, the laminate comprises glass, adhesive film and battery cells stacked in layers; operating on glass of the laminate to form cracks in the glass and separate the glass into pieces; placing the laminate with the crack in a soaking liquid to immerse the adhesive film; After the soaking, the glass and the adhesive film in the laminate are separated to obtain a plurality of glass blocks.

[0007] The above technical solution adopted in the embodiment of the present application may have the following advantages: The embodiment of the present application is suitable for the separation process of glass in a laminate. First, the whole piece of glass on the laminate is broken to obtain glass including cracks. Then, the glass is immersed in an immersion liquid so that the immersion liquid enters the adhesive film through the cracks, so that the adhesive film swells and reduces the bonding force. Then, the glass and the adhesive film are separated. This method can recycle large-area glass with controllable size. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in the present application and should not be regarded as limiting the scope of the present application.

[0009] Figure 1 is a flow chart of a method for separating and recycling glass in a photovoltaic module provided in an embodiment of the present application; Figure 2 A side view of a cutting device provided in an embodiment of the present application; Figure 3 A front view of a cutting device provided in an embodiment of the present application; Figure 4 A side view of a cutting device provided in another embodiment of the present application; Figure 5 A front view of a cutting device provided in another embodiment of the present application; Description of reference numerals: 1-Laminate; 2-Cutting machine table; 3-Baffle; 4-Material collection box; 5-Track chute; 6-Support seat; 7-Cutter; 8-Bearing; 9-Bearing connector; 10-Cutter base; 11-Cutter connector. DETAILED DESCRIPTION

[0010] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other in the absence of conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0011] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0012] In the present application, when it comes to a numerical interval (i.e., a numerical range), unless otherwise specified, the distribution of the optional numerical values ​​in the numerical interval is considered to be continuous, and includes the two numerical endpoints (i.e., the minimum and maximum values) of the numerical interval, and each numerical value between the two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to an integer in the numerical interval, it includes the two endpoint integers of the numerical range, and each integer between the two endpoints, which is equivalent to directly listing each integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be merged. In other words, unless otherwise specified, the numerical range disclosed in the present application should be understood to include any and all sub-ranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. "Numerical interval" allows for broadly including quantitative intervals such as percentage intervals, ratio intervals, and ratio intervals.

[0013] The embodiment of the present application provides a method for separating and recycling glass in a photovoltaic module. Based on this, the problem of small glass recycling area is solved. See below for details.

[0014] Hereinafter, exemplary embodiments according to the present application will be described in more detail with reference to the accompanying drawings. It should be noted that these exemplary embodiments can be implemented in many different forms and should not be construed as being limited to the embodiments described herein.

[0015] In some embodiments, the flow chart of the method for separating and recycling glass in the photovoltaic module is as follows: Figure 1 The method for separating and recycling glass in a photovoltaic module comprises the following operations: S1. Provide a photovoltaic module and obtain a laminate 1 of the photovoltaic module; wherein the laminate 1 includes glass, an adhesive film and a battery cell that are stacked.

[0016] Optionally, the photovoltaic components may be waste photovoltaic components that have completed their service life or have been retired early, or defective photovoltaic components that have failed to meet production standards may be used.

[0017] In some embodiments, the photovoltaic module includes an aluminum frame, a first glass, a first adhesive film, a battery cell, a second adhesive film, a second glass (or a back panel), and a junction box; after the aluminum frame and the junction box are mechanically removed, the remaining part is the laminate 1.

[0018] In some specific embodiments, the laminate 1 includes a first glass, a first adhesive film, a battery sheet, a second adhesive film and a second glass stacked in sequence. In this case, it is double-sided glass.

[0019] In some other specific embodiments, the laminate 1 includes a first glass, a first adhesive film, a battery sheet, a second adhesive film and a back plate which are stacked in sequence. In this case, it is single-sided glass.

[0020] It can be understood that the glass on the laminate 1 is bonded to the battery cell by the adhesive film. Since the adhesive film has a strong adhesive force after lamination, it is difficult to separate the glass.

[0021] In some embodiments, the adhesive film may include at least one of an ethylene-vinyl acetate copolymer, a co-extruded polymer of ethylene-vinyl acetate and ethylene-octene, and an ethylene-octene copolymer.

[0022] S2. Operating on the glass of the laminate 1 to form cracks on the glass to divide the glass into several pieces; thereby, cracks are formed on the glass, which not only separates the glass but also facilitates the subsequent immersion process so that the immersion liquid contacts the adhesive film and the adhesive film swells.

[0023] The cracks divide the glass into two parts with an average area of ​​1 cm 2 ~25cm 2 The glass block, for example, is divided into sections with an average area of ​​1 cm 2 , 5cm 2 、15cm 2 , 20cm 2 、25cm 2 Thus, it is convenient to obtain glass blocks with larger average area later.

[0024] In some specific embodiments, the glass of the laminate 1 can be cut by a glass cutter to obtain glass blocks with controllable sizes.

[0025] S3, placing the laminate 1 with the crack in a soaking liquid to immerse the adhesive film so as to swell the adhesive film; thereby facilitating the subsequent separation of the glass and the adhesive film.

[0026] In some embodiments, the soaking includes: the soaking liquid is alkaline solution, and the soaking is carried out at 60° C. to 85° C. for more than 30 minutes, thereby swelling the film and reducing the adhesive force.

[0027] Preferably, the alkali solution includes 20wt% to 30wt% sodium hydroxide solution; and / or, the soaking temperature can be 75°C to 85°C; and / or, the soaking time is 30min to 40min. Thus, the swelling degree of the film is increased, so that the adhesive force of the film is lower. For example, the alkali solution can be 20wt%, 25wt%, or 30wt% sodium hydroxide solution; the soaking temperature can be 75°C, 80°C, or 85°C; and the soaking time can be 30min, 35min, or 40min.

[0028] S4. After the soaking, the glass and the adhesive film in the laminate 1 are separated to obtain a plurality of glass blocks.

[0029] In some embodiments, the separation of the glass and the adhesive film in the laminate 1 includes: cutting the laminate 1 with a cutting device to form a cutting surface on the adhesive film so as to obtain the glass with part of the adhesive film; peeling off the adhesive film on the glass to obtain a plurality of glass blocks. Thus, the glass blocks are obtained in two steps, firstly the glass is cut off as a whole, and then the part of the adhesive film on the glass is cut to obtain the glass blocks. Furthermore, when cutting, the cutter 7 is aligned with the adhesive film at a position of 0.01cm to 0.5cm away from the glass, for example, it can be at a position of 0.01cm, 0.1cm, 0.25cm, 0.5cm, etc. away from the glass. Thus, the thickness of the adhesive film attached to the glass is minimized to facilitate thorough peeling.

[0030] In some embodiments, the cutting device includes a cutting machine 2 and a cutter 7; the bearing surface of the cutting machine 2 is used to place and fix the laminate 1; the cutter 7 is arranged parallel to the adhesive film; when cutting, the cutter 7 and the bearing surface can produce relative movement, so that the cutter 7 moves from one end of the laminate 1 to the other end of the laminate 1, so as to complete the cutting of the entire adhesive film. In this way, the cutting and separation of the entire glass and the adhesive film is completed. Furthermore, the bearing surface of the cutting machine 2 includes an inclined plane or a developable curved surface. The cutter 7 includes a cutting knife or a cutting wire.

[0031] In some specific embodiments, the cutter 7 moves to cut the entire adhesive film; or the bearing surface moves to cut the entire adhesive film.

[0032] It is worth noting that the developable curved surface refers to a curve that can be developed into a plane without deformation, such as a cylindrical surface, thereby facilitating the placement of the laminate 1.

[0033] In some specific embodiments, the cutting device is Figure 2 and Figure 3As shown, the cutting device includes a cutting machine table 2, the bearing surface of the cutting machine table 2 is an inclined plane, the lower end of the bearing surface of the cutting machine table 2 is provided with a baffle 3, the starting end of the bearing surface of the cutting machine table 2 is provided with a support seat 6, a cutter 7 is installed on the support seat 6, both sides of the bearing surface are provided with a track chute 5 to provide a travel for the cutter 7, and a material collection box 4 is provided below the end of the cutting machine table 2. When cutting, the laminate 1 is fixed on the bearing surface, and the support seat 6 moves with the cutter 7 from the starting end along the track chute 5 to the end, cutting off the glass and part of the film, and the cut materials slide into the material collection box 4.

[0034] In other specific embodiments, the cutting device is Figure 4 and Figure 5 As shown, the cutting device includes a cutting machine table 2, a cutter 7, a bearing 8, a bearing connector 9, a cutter base 10 and a cutter connector 11. The cutting machine table 2 is cylindrical, and the bearing surface on the cutting machine table 2 is a cylindrical surface. A bearing 8 is provided at the center of the cutting machine table 2, and a bearing connector 9 for external connection is provided on the bearing 8; the cutter 7 is fixed to the cutter base 10 through the cutter connector 11; when cutting, the laminate 1 is fixed on the cylindrical bearing surface, the cutter 7 is aligned with the film of the laminate 1, and the cutting machine table 2 rotates along the bearing 8, thereby, the cutter 7 completes the cutting of the entire laminate 1.

[0035] Optionally, the bearing surface of the cutting machine table 2 has a diameter of 600 mm to 1000 mm and a length of 1000 mm to 1500 mm, so that it can be applied to the mainstream photovoltaic module formats and sizes on the market.

[0036] The following will conduct performance tests on the method for separating and recycling glass in the photovoltaic module provided in the embodiments of the present application and related comparative examples.

[0037] [Example 1] Step 1: providing a photovoltaic module, the photovoltaic module comprising an aluminum frame, front glass, front adhesive film, battery cells, back adhesive film, back sheet and junction box; removing the aluminum frame and junction box, and the remaining part is a laminate 1; Among them, the thickness of the front glass is 4.0mm; the material of the front film is ethylene-vinyl acetate copolymer film, and the thickness is 1.0mm; the battery cell is a passivated emitter and a back battery, and the side length of the battery cell can be 180mm~185mm, and it is 182mm here; the material of the back film is ethylene-vinyl acetate copolymer film, and the thickness is 1.0mm; Step 2: Scrape the front glass of laminate 1 to break it into multiple glass pieces with an average area of ​​15 cm 2 .

[0038] Step 3: placing the laminate 1 in a soaking liquid of 20wt% sodium hydroxide solution, immersing the laminate 1 in the soaking liquid, and soaking at 85°C for 40 minutes, so that the sodium hydroxide solution penetrates into the front adhesive film through the cracks, causing the front adhesive film to swell, thereby reducing the bonding force between the front glass and the front adhesive film; Step 4: Place the soaked laminate 1 on the carrying surface of the cutting machine 2, set the cutter 7 parallel to the front adhesive film, align the cutter 7 with the front adhesive film at a position 0.25 cm away from the glass, and move the cutter 7 from one end of the laminate 1 to the other end of the laminate 1 to complete the cutting; The front adhesive film on the front glass is peeled off to obtain several glass blocks.

[0039] [Example 2 to Example 9] The other operations of Examples 2 to 9 are the same as those of Example 1, except that the soaking conditions in step 3 are different. The relevant variables are shown in Table 1.

[0040]

Test example

[0041] Among them, glass recovery rate = weight of peeled glass / weight of original laminated glass × %.

[0042] The average area of ​​recycled glass is obtained by taking a photo to obtain an image of the glass, then using image processing software to measure the area, and then solving for the average area based on the measured area.

[0043] Table 1

[0044] As shown in Table 1, the glass recovery rate of Examples 1 to 3 can reach 100%, and the average area of ​​the recovered peeled pieces is 15 cm 2, the glass blocks can maintain good consistency before and after immersion and peeling; at this time, the corresponding conditions are: 20% to 30% mass percentage of sodium hydroxide solution, 30min to 40min immersion time, 75℃ to 85℃ immersion temperature, all of which can achieve 100% glass recovery rate. Compared with Example 1, the immersion temperature of Examples 4 to 6 is lower than 70℃, and the glass recovery rate is greatly reduced to only 29% to 76%. Examples 7 to 9 and Example 1, under the premise of keeping the concentration of the immersion liquid unchanged, that is, the mass percentage of the sodium hydroxide solution is 20%, the immersion temperature is reduced to 65℃ to 70℃, and the immersion time needs to be extended to more than 60min to achieve 100% glass recovery rate. It can be seen from Examples 1 and 9 that under the same immersion time and immersion temperature conditions, the glass recovery rate is greatly reduced by reducing the concentration of the sodium hydroxide solution, which is only 65%. This is because the insufficient swelling of the film leads to the incomplete loss of the bonding force between the film and the glass, resulting in a significant decrease in the glass recovery rate.

[0045] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0046] For the convenience of description, the orientation or position relationship indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, vertical, horizontal" and "top, bottom" is usually based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description. Unless otherwise stated, these directional words do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present application; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Therefore, the exemplary term "above..." can include both "above..." and "below..." orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used here are interpreted accordingly.

[0047] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0048] Unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is lower in level than the second feature.

[0049] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so that once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0050] It should also be noted that "one embodiment", "another embodiment", "embodiment", etc. mentioned in this specification refer to the specific features, structures or characteristics described in conjunction with the embodiment included in at least one embodiment generally described in this application. The same expression appearing in multiple places in the specification does not necessarily refer to the same embodiment. Further, when describing a specific feature, structure or characteristic in conjunction with any embodiment, it is claimed that the realization of such feature, structure or characteristic in conjunction with other embodiments also falls within the scope of this application.

[0051] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0052] It should also be noted that the above are only preferred embodiments of the present application, and the patent protection scope of the present application is not limited thereto. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for separating and recycling glass in photovoltaic modules, characterized in that: The following operations are included: Providing a photovoltaic module, obtaining a laminate of the photovoltaic module; Wherein, the laminate comprises glass, adhesive film and battery cells stacked in layers; operating on glass of the laminate to form cracks in the glass and separate the glass into pieces; placing the laminate with the crack in a soaking liquid to immerse the adhesive film; After the soaking, the glass and the adhesive film in the laminate are separated to obtain a plurality of glass blocks.

2. The method for separating and recycling glass in photovoltaic modules according to claim 1, characterized in that: The cracks divide the glass into two parts with an average area of ​​1 cm 2 ~25cm 2 of glass blocks.

3. The method for separating and recycling glass in photovoltaic modules according to claim 1, characterized in that: The soaking comprises: The soaking liquid is alkaline solution, and the soaking is carried out at 60° C. to 85° C. for more than 30 minutes.

4. The method for separating and recycling glass in photovoltaic modules according to claim 3, characterized in that: The alkali solution includes 20wt% to 30wt% of sodium hydroxide solution, the soaking temperature is 75°C to 85°C, and the soaking time is 30min to 40min.

5. The method for separating and recycling glass in photovoltaic modules according to claim 1, characterized in that: The separation of the glass and the adhesive film in the laminate comprises: Cutting the laminate to form a cutting surface on the adhesive film so as to obtain the glass with a portion of the adhesive film; The adhesive film on the glass is peeled off to obtain a plurality of glass blocks.

6. The method for separating and recycling glass in photovoltaic modules according to claim 5, characterized in that: The laminate is cut using a cutting device, wherein the cutting device comprises a cutting table (2) and a cutter (7); The bearing surface of the cutting machine table (2) is used for placing the laminated component; The cutter (7) is arranged relative to the adhesive film so as to cut the adhesive film; When cutting, the cutter (7) and the bearing surface can generate relative movement so that the cutter (7) can complete the cutting of the entire adhesive film.

7. The method for separating and recycling glass in photovoltaic modules according to claim 6, characterized in that: The bearing surface of the cutting machine table (2) comprises an inclined plane or a developable curved surface; and / or The cutter (7) comprises a cutting knife or a cutting wire.

8. The method for separating and recycling glass in photovoltaic modules according to claim 6, characterized in that: When cutting, the cutter (7) is located at a position where the adhesive film is 0.01 cm to 0.5 cm away from the glass.

9. The method for separating and recycling glass in photovoltaic modules according to claim 1, characterized in that: The glass includes a first glass and a second glass, the adhesive film includes a first adhesive film and a second adhesive film, and the laminate includes the first glass, the first adhesive film, the battery cell, the second adhesive film and the second glass stacked in sequence; Alternatively, the adhesive film includes a first adhesive film and a second adhesive film, and the laminate includes the glass, the first adhesive film, the battery cell, the second adhesive film and a backplane stacked in sequence.

10. The method for separating and recycling glass in photovoltaic modules according to claim 9, characterized in that: The first adhesive film comprises at least one of ethylene-vinyl acetate copolymer, ethylene-vinyl acetate and ethylene-octene co-extruded polymer, and ethylene-octene copolymer; and / or The second adhesive film includes at least one of ethylene-vinyl acetate copolymer, ethylene-vinyl acetate and ethylene-octene co-extruded polymer, and ethylene-octene copolymer.

Images