Backsheet cutting and scrap recycling process for photovoltaic modules

Abstract

The application relates to a back plate cutting and scrap recycling process of a photovoltaic module, and comprises the following steps: S1. main cutting; S2. auxiliary cutting; and S3. scrap collecting. One aspect of the application is based on the cooperation of the partition or layering of the multi-section main cutting area, combined with the auxiliary cutting and crushing, which not only shovels off the residual or remaining scrap on the surface of the cell piece, but also forms a lateral limit and a warping limit through the auxiliary cutting, thereby assisting the smooth cutting and horizontal transmission of the photovoltaic module, reducing the damage rate of the cell piece and improving the intact recovery rate of the brittle glass base layer. The other aspect of the application is scrap collecting, which is suitable for any physical cutting and does not produce waste water and fluorine gas. Meanwhile, the negative pressure airflow generates a small stress in the vertical direction on the cell piece, and the negative pressure airflow assists the auxiliary cutting and crushing, eliminating the adsorption blockage caused by the large-volume scrap. In addition, the secondary adhesion rate of the scrap is low, the mixing rate of the scrap is reduced, the scattered, shoveled and negative pressure collected scrap is gathered and concentrated, and the labor cost is reduced.

Description

Technical Field

[0001] This invention belongs to the field of environmental protection technology, specifically relating to a process for backsheet cutting and waste recycling of photovoltaic modules. Background Technology

[0002] A photovoltaic (PV) module is a power generation device that produces direct current (DC) electricity when exposed to sunlight. It consists of thin, solid-state photovoltaic cells made almost entirely of semiconductor materials (such as silicon). Specifically, it includes a glass plate, EVA adhesive layer, solar cells, backsheet, junction box, and frame. More than 90% of the materials can be recycled and reused, resulting in considerable recycling value and high economic profits. Therefore, it is necessary to recycle PV modules after they have reached the end of their lifespan. This not only alleviates the shortage of raw materials for PV devices to some extent, but also avoids environmental pollution. In other words, it transforms solar cells from solid waste into useful raw materials, while also effectively carrying out environmental governance and protecting the environment.

[0003] However, when pyrolysis is used to remove the backsheet, we know that the backsheet mainly consists of a PET base film, an outer fluorine film formed on the front and back of the PET base film by adhesives, and an inner and outer fluorine film. During the pyrolysis process, the fluorine film will produce fluorine gas, which is not only toxic and pollutes the environment, but also the residues, silicon, glass and other materials after pyrolysis are all mixed together. In addition, silicon and silicon dioxide are inherently difficult to separate. Therefore, the purity of the recovered silicon cannot meet the requirements.

[0004] Currently, most backplate removal methods primarily employ physical methods, using wet grinding and wet cutting to remove the backplate. However, in practice, the following technical drawbacks exist: 1. Physical removal often fails to completely remove the adhesive layer and fluorine film from the cell surface, leaving residues. Furthermore, cutting debris, especially in wet grinding or wet cutting, easily adheres to the cell surface. This residue and adhered contaminants form a silicon mixture, affecting not only silicon separation but also the purity of the recycled silicon. Additionally, while wet cutting suppresses dust, it forcibly mixes PET micropowder, fluorine film particles, glass dust, and aged adhesives into the liquid phase, creating a highly suspended, difficult-to-settle organic-inorganic composite slurry. Trace amounts of fluoride in this wastewater, if not finely filtered, can easily cause secondary soil / water pollution. Simultaneously, backsheet debris is difficult to detach from the cell surface with the flowing cutting fluid. Therefore, the debris adsorbed on the cell surface forms a mixture, increasing the difficulty of silicon separation and consequently affecting silicon purity. 2. In physical cutting, when the waste chips are in the form of large blocks or strips, the waste chips not only require a large adsorption force, but also significantly increase the blockage rate of the adsorption port. At the same time, the waste chips that are re-adhered to the surface of the solar cells or remain on the surface of the solar cells during cutting cannot be removed from the surface of the solar cells. Therefore, the waste chips that remain or adhere to the surface of the solar cells will form a mixture, which not only increases the difficulty of silicon separation, but also affects the purity of the recycled silicon. 3. It is difficult to control lateral stress during physical removal, especially when grinding the tail end of the module. The rigid module is prone to transient warping and micro-displacement, which not only significantly increases the edge chipping and microcrack rate of the solar cells, but also directly threatens the integrity of the brittle glass substrate (making it extremely difficult to achieve non-destructive recycling of the entire glass panel). 4. Waste and suspended particles are difficult to collect and cannot be effectively centrally processed. Therefore, a large amount of manpower is needed for decentralized collection. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a novel waste collection process for removing backsheets from photovoltaic modules.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A backsheet cutting and waste recycling process for photovoltaic modules, comprising a backsheet removal device including a cutting unit and a waste recycling unit, wherein the cutting unit includes a set of parallel and co-rotating conveyor rollers, a main cutting component, and an auxiliary cutting component, and the waste recycling unit includes a leakage receiving component, a negative pressure collection component, and a material collection component arranged below the conveyor rollers, wherein the negative pressure collection component uses negative pressure to assist the auxiliary cutting to break down the waste from the detached solar cells, and includes the following steps: S1. Main Cutter The main cutting channel is formed by the main cutting component and the transfer roller group. The main cutting channel is distributed at intervals in the transmission direction of the photovoltaic module and forms multiple main cutting zones. The glass layer of the photovoltaic module is attached to the transfer roller surface and the back sheet layer is facing upwards and passes through each main cutting zone in sequence. The back sheet layer is removed by the partitioning or layering of multiple main cutting zones. S2. Auxiliary cutting The auxiliary cutting channel is formed by the auxiliary cutting component and the conveying roller group. The auxiliary cutting component used in the auxiliary cutting channel is based on the reverse scraping and combing and breaking in the opposite direction of the photovoltaic module's transmission direction. It assists the main cutting with lateral restraint and warping restraint, and removes the waste residue or residual waste on the surface of the cell. Under the negative pressure cooperation formed by the negative pressure collection component along the reverse scraping angle, the auxiliary cutting component scrapes and breaks the waste synchronously. The auxiliary cutting component includes scraping blades and combing blades. S3. Debris Collection First, the waste debris scattered from the main and auxiliary cutting processes is collected and transferred forward and downward along the photovoltaic module's transmission direction, with the end of the transfer forming a leakage collection point. Second, the negative pressure collection module is connected to the auxiliary cutting channel. The waste debris and suspended particles after being cut by the auxiliary cutting module are collected upward along the groove area formed by the angle of the shovel and the comb teeth by the negative pressure airflow to the negative pressure hopper. Then, the waste debris is separated by solid-gas separation, and the separated waste debris converges, with the outlet forming a negative pressure collection point. Finally, a material collection module is used to connect the leakage collection point and the negative pressure collection point, and the collected waste debris is concentrated at the convergence point.

[0007] According to a specific embodiment and preferred aspect of the present invention, in step S1, each segment of the main cutting area is provided with a main cutting tool, and the main cutting area formed by the cooperation of multiple main cutting tools covers the width of the photovoltaic module, and the total cutting amount formed is equal to the thickness of the backsheet layer; or, the main cutting area formed by the cooperation of multiple main cutting tools covers the width of the photovoltaic module, and the cutting amount of each main cutting tool is equal to the thickness of the backsheet layer, while the multiple main cutting areas are staggered and complementary in the width direction of the backsheet layer.

[0008] Preferably, the cutting areas formed by each main cutting tool are of equal width, and the cutting amount is equal to the backsheet layer thickness; multiple sets of main cutting tools are staggered and complementary in the width direction of the backsheet layer. A zoned processing method is adopted, first grooving, then cutting to achieve complete removal; furthermore, each main cutting tool includes multiple spaced disc cutters. Each main cutting tool uses multiple sets of disc cutters (disc cutters), arranged back and forth along the feed direction, and staggered and complementary in the axial (width direction), so that the cutting areas of each set of disc cutters collectively cover the entire width of the photovoltaic module, thereby achieving seamless connection of cutting trajectories between adjacent disc cutters, avoiding residue or overcutting. Simultaneously, based on the different cutting directions of each row of disc cutters, lateral stresses are mutually canceled, thereby significantly reducing the total lateral bending moment applied to the backsheet, effectively suppressing warping, bending, and edge tearing. Alternatively, each main cutting tool is a hob, wherein the hob has multiple inserts arranged side-by-side and spaced on a roller, with each insert having an equal width and spacing. The use of offset and complementary roller cutters to cut the photovoltaic module across its entire width, along with the staggered layout and sequential cutting, can mutually limit the lateral displacement of the photovoltaic module, effectively suppressing warping, bending, and edge tearing.

[0009] Alternatively, each main cutting tool can be a wide hob with continuous cutting edges covering the entire backing plate layer, and the sum of the cutting amounts formed by each hob is equal to the thickness of the backing plate layer. By employing a layered cutting method to gradually remove the backing plate, this approach not only minimizes lateral stress on the assembly but also distributes the total cutting depth proportionally among multiple wide hobs with continuous cutting edges covering the entire width of the backing plate layer. This significantly reduces the instantaneous cutting area and peak cutting force of each cut, bringing the resultant force direction closer to the feed direction. This fundamentally suppresses the risks of lateral slippage, elastic rebound, bending warping, and edge tearing of the backing plate. Simultaneously, because the cutting depth shared by each hob is relatively uniform and constant, the cutting load fluctuation is small, the impact load is reduced, the tool wear rate is more predictable, and the cutting edge life is extended. Furthermore, the wide hob completes the full-width cutting in a single pass, eliminating the need for multiple tool passes and connections. Therefore, the machining efficiency is high, tool marks and step defects are almost eliminated, and the final cross-section achieves a high level of straightness, parallelism, and surface integrity.

[0010] According to another specific embodiment and preferred aspect of the present invention, the transfer roller assembly includes multiple transfer rollers arranged side by side and spaced apart, with the top surfaces of the multiple transfer rollers forming a transfer surface. A transfer roller is positioned directly below each main cutting tool, and these transfer rollers are alignment transfer rollers. The supporting force generated by the alignment transfer rollers and the vertical stress generated by cutting are in a state of dynamic equilibrium. Generally, the cutting position is aligned with the top of the alignment transfer roller, and the cutting position is vertically aligned with the axis of the alignment transfer roller below. In short, the current position formed by the cutting and support is in a state of force equilibrium in the vertical direction, thereby eliminating warping and bending of the photovoltaic module caused by the instantaneous cutting.

[0011] According to another specific embodiment and preferred aspect of the present invention, in step S2, the angle between the abutment formed by the abutment blade and the surface of the battery cell is β, where 0°≤β<90°. Generally, 0°≤β≤15°. In short, the smaller the angle between the abutment blade and the surface of the battery cell, the better. When β=0°, it means that the flat abutment is performed entirely along the horizontal direction. On the one hand, this not only avoids generating stress in the vertical direction that could cause scratches on the surface of the battery cell, but also improves cutting and transmission stability based on the constraint formed by the flat abutment. On the other hand, the negative pressure adsorption guide formed not only eliminates the vertical stress caused by upward adsorption, but also more smoothly draws debris into the adsorption port.

[0012] According to another specific embodiment and preferred aspect of the present invention, the scraping tool includes a bottom scraper plate, a connecting plate, and an end sealing plate. The bottom scraper plate forms a scraping surface on the side near the main scraping component. The connecting plate is located on the opposite side of the scraping surface and is fixed to the negative pressure collection component. The end sealing plate connects and fixes the bottom scraper plate and the connecting plate to their opposite ends in the negative pressure collection component to form a scraping cavity. The scraping cavity extends along the width direction of the photovoltaic module, and an opening between the scraping surface and the negative pressure collection component forms an adsorption port. When the scraping surface scrapes against the surface of the solar cell, waste debris enters the scraping cavity from the adsorption port. Based on the formation of the scraping cavity, not only is the direction of the negative pressure airflow changed, but also a retention space is provided for scraping away waste debris, reducing the probability of secondary adhesion of scraped debris to the solar cell.

[0013] Preferably, the shovel surface is inclined from bottom to top, and the bottom shovel plate presses flat on the surface of the solar cell. Based on the design of the inclined shovel surface, not only can the shoveled waste be guided into the shovel cavity, but the formed blade can also completely remove residual or remaining waste on the surface of the solar cell.

[0014] According to another specific embodiment and preferred aspect of the present invention, the tooth grooves of the comb-tooth cutter are arranged side by side at intervals along the width direction of the photovoltaic module, and the comb-tooth cutter includes multiple cutter bodies spaced apart along the length direction of the shovel cavity. A comb groove is formed between two adjacent cutter bodies. The projection of each cutter body in the thickness direction of the bottom shovel plate and the connecting plate is triangular, and the comb-tooth edge formed by each cutter body extends obliquely from bottom to top. Based on the comb-tooth cutter for crushing, large-volume waste chips are prevented from failing to detach smoothly from the surface of the solar cells, reducing the probability of material mixing caused by waste chips. At the same time, the uniquely shaped cutter body layout not only achieves the required crushing function, but also effectively guides the flow, allowing the waste chips to flow more smoothly into the negative pressure hopper.

[0015] Preferably, the triangle is an isosceles triangle. This not only facilitates the fragmentation of waste materials, but also creates a guide that is more conducive to the deflection and transfer of the waste material and airflow mixture.

[0016] Preferably, the shovel surface and each comb tooth edge have the same inclination angle. The scraped waste chips move gradually inward relative to the comb tooth edges as the negative pressure process proceeds, thereby facilitating the breaking down of large-volume block or strip-shaped waste chips.

[0017] Furthermore, the comb teeth and the shovel surface are coplanar. This coplanarity means that the plane formed by the alignment of the comb teeth and the shovel surface are on the same plane. The biggest advantage of this setting is that it makes shoveling and cutting work together, avoids waste chips from getting tangled in the comb teeth, improves the crushing efficiency and quality, and is more conducive to crushing large-volume block or strip-shaped waste chips under negative pressure.

[0018] Even better, the upper end of each comb blade is located between the top edge of the adsorption port and the top edge of the connecting plate. Based on the angle and position layout, the volume of the shovel chamber increases vertically from bottom to top, which not only facilitates the smooth passage of the crushed waste and the negative pressure mixed airflow, but also, in conjunction with the negative pressure, is more conducive to the crushing of waste and the adsorption of suspended waste particles.

[0019] According to another specific embodiment and preferred aspect of the present invention, the transmission roller assembly includes multiple transmission rollers arranged side-by-side and spaced apart. The top surfaces of the multiple transmission rollers constitute a transmission surface. A transmission roller is positioned directly below the bottom shovel plate, and the transmission roller is an aligned transmission roller. The supporting force formed by the aligned transmission roller and the vertical stress formed by the bottom shovel plate are in a state of dynamic equilibrium. Based on the fact that the current position formed by the shoveling and support is in a state of force equilibrium in the vertical direction, the warping and bending of the photovoltaic module caused by the instant of shoveling is eliminated.

[0020] Preferably, the negative pressure collection assembly includes a negative pressure hopper, a separator, and a dust collector. A connecting plate and an end-sealing plate are fixed to the negative pressure hopper, and a baffle plate is positioned above the cutting surface of the negative pressure hopper, with an opening between the baffle plate and the cutting surface forming an adsorption port. Material is drawn in based on the negative pressure generated by the separator, followed by solid-gas separation. The separated solid waste is collected by the negative pressure, and the separated waste gas enters the dust collector and is then discharged.

[0021] Preferably, the separator is a cyclone separator. Separation is achieved using centrifugal force, and it is a commonly purchased product.

[0022] Preferably, the dust collector is a bag filter dust collector. It is mainly used for exhaust gas purification and is a commonly purchased product.

[0023] In addition, in step S3, the material collection assembly uses a ring conveyor belt to connect the leakage collection points and the negative pressure collection points.

[0024] Preferably, the material collection assembly includes an annular conveyor belt group and a collection hopper. The annular conveyor belt group includes a first conveyor belt and a second conveyor belt connected from opposite ends. The first conveyor belt is horizontally positioned and connects the leakage collection point and the negative pressure collection point. The second conveyor belt is inclined from bottom to top, with its lower end connected to the first conveyor belt and the collection hopper installed at its upper end. The discharge port of the collection hopper constitutes a convergence point. Based on the convergence point setting, only the receiving frame needs to be used, and operators can replace the frame periodically, which not only saves labor costs but also promotes the intelligent development of backplate removal.

[0025] Due to the implementation of the above technical solutions, the present invention has the following advantages compared with the prior art: 1. Based on the partitioned or layered cooperation of the multi-segment main cutting zone, combined with auxiliary cutting and crushing, not only are the residual or remaining waste chips on the surface of the solar cell relatively removed, but the cutting and crushing cooperation can also form lateral restraint and warping restraint, assisting the photovoltaic module to cut smoothly and transport horizontally, reducing the damage rate of the solar cell (edge ​​chipping and microcrack rate) and improving the integrity and non-destructive recycling rate of brittle glass substrate. 2. Based on the collaboration of leakage connection and negative pressure collection, the battery surface is collected without any residue or residue. It is not only suitable for any kind of physical cutting, but also generates no wastewater or fluorine gas. At the same time, based on the negative pressure airflow along the backhoe angle, the battery cells are subjected to a small vertical stress pull. The negative pressure airflow assists in cutting and breaking down, eliminating the adsorption and blockage caused by large-volume waste. In addition, the secondary adhesion rate of waste is low, reducing the mixing rate of waste. Furthermore, the scattered, scraped, and negative pressure collected materials are gathered and concentrated, reducing labor costs. 3. A zoned processing method is adopted, first grooving and then cutting to achieve comprehensive removal; each main cutting tool includes multiple spaced disc cutters, each using multiple sets of disc cutters (disc cutters) arranged back and forth along the feed direction, and staggered and complementary in the axial (width direction), so that the cutting area of ​​each set of disc cutters covers the entire width of the photovoltaic module, thereby achieving seamless connection of cutting trajectories between adjacent disc cutters, avoiding residue or overcutting. At the same time, based on the different cutting directions of each row of disc cutters, the lateral stress is mutually canceled, thereby significantly reducing the total lateral bending moment applied to the backsheet, effectively suppressing warping, bending and edge tearing. Alternatively, staggered and complementary hobbing cutters are used to cut the entire width of the photovoltaic module, and the staggered layout and sequential cutting can also mutually limit the lateral displacement of the photovoltaic module, effectively suppressing warping, bending and edge tearing. 4. By employing a layered cutting method to gradually remove the back plate, this approach not only minimizes lateral stress on the component but also distributes the total cutting depth proportionally to multiple continuous cutting edges of a wide-width hob covering the entire width of the back plate layer. This significantly reduces the instantaneous cutting area and peak cutting force of each cut, bringing the resultant force direction closer to the feed direction. This fundamentally suppresses the risks of lateral slippage, elastic rebound, bending warping, and edge tearing of the back plate. Simultaneously, because the cutting depth shared by each hob is relatively uniform and constant, the cutting load fluctuation is small, the impact load is reduced, the tool wear rate is more predictable, and the cutting edge life is extended. Furthermore, the wide-width hob completes the full-width cutting in one pass, eliminating the need for multiple tool passes and joints. As a result, the processing efficiency is high, tool marks and step defects are almost eliminated, and the final cross-section achieves a high level of straightness, parallelism, and surface integrity. 5. The cutting position is aligned with the top of the alignment transfer roller, and the cutting position is aligned vertically with the axis of the alignment transfer roller below. In short, the current position formed by the scraping and support is in a state of force balance in the vertical direction, so as to eliminate the warping and bending of the photovoltaic module caused by the scraping moment. 6. The angle between the scraper formed by the scraper and the surface of the solar cell is β. Generally, 0°≤β≤15°. In short, the smaller the angle between the scraper and the surface of the solar cell, the better. When β=0°, it means that the scraping is performed completely horizontally. On the one hand, this not only avoids stress in the vertical direction that could cause scratches on the surface of the solar cell, but also improves cutting and transmission stability based on the constraint formed by the flat scraper. On the other hand, the negative pressure adsorption guide formed not only eliminates the vertical stress caused by upward adsorption, but also more smoothly draws debris into the adsorption port. 7. Based on the forming of the scraping cavity, not only is the direction of negative pressure airflow changed, but also a storage space is provided for scraping off the waste, reducing the probability of scraping off the waste adhering to the battery cell again; at the same time, based on the design of the inclined scraping surface, not only can the scraped waste be guided into the scraping cavity, but the formed blade can also completely remove the residual or remaining waste on the surface of the battery cell.

[0026] 8. Based on the toothed blades for crushing, large-volume waste chips are prevented from failing to detach smoothly from the surface of the battery cells, reducing the probability of material mixing caused by waste chips. At the same time, the uniquely shaped blade layout not only achieves the required crushing function, but also effectively guides the flow, smoothing the waste chips to the negative pressure hopper; the triangle is an isosceles triangle. Not only is it more conducive to the fragmentation of waste chips, but the resulting guide is also more conducive to the change and transfer of the waste chip and airflow mixture. The inclination angles of the shoveling surface and each comb tooth blade are equal. The shoveled waste chips move gradually inward along with the negative pressure flow, relatively close to the comb tooth blades, thus facilitating the fragmentation of large-volume block or strip-shaped waste chips. The plane formed by the alignment of each comb tooth blade and the shoveling surface are in the same plane. The biggest advantage of this setting is that it makes shoveling and cutting work together, avoiding waste chips from entangled in the comb tooth blades, improving fragmentation efficiency and quality. At the same time, it is more conducive to the fragmentation of large-volume block or strip-shaped waste chips under the drive of negative pressure. In addition, based on the angle and position layout, the volume of the shoveling chamber increases vertically from bottom to top, which not only facilitates the smooth passage of fragmented waste chips and negative pressure mixed airflow, but also, in conjunction with negative pressure, is more conducive to the fragmentation of waste chips and the adsorption of suspended waste chip particles.

[0027] 9. Material is drawn in by the negative pressure generated by the separator, and then solid and gas are separated. The separated solid waste is collected by the negative pressure, and the separated waste gas is discharged after entering the dust collector. 10. Based on the setting of the convergence point, only the receiving frame needs to be set up. Operators can change the frame periodically, which not only saves labor costs, but also promotes the intelligent development of backplate removal. Attached Figure Description

[0028] Figure 1 This is a schematic diagram (first view) of the photovoltaic module backsheet removal device of the present invention. Figure 2 This is a structural schematic diagram (second perspective) of the photovoltaic module backsheet removal device of the present invention. Figure 3 for Figure 1 Schematic diagram of the intermediate cutting unit; Figure 4 for Figure 3 A half-section diagram; Figure 5 for Figure 1 A schematic diagram of the structure of the medium negative pressure bucket and auxiliary cutting components; Figure 6 for Figure 5 Front view diagram; Figure 7 for Figure 6 Schematic diagram of the BB-direction section; Figure 8 for Figure 6 Schematic diagram of cross-section along the CC direction; The components are as follows: 1. Cutting unit; 10. Transfer roller group; 100. Transfer roller; 11. Main cutting assembly; 110. Main cutting tool; 12. Auxiliary cutting assembly; D. Shovel tool; 120. Bottom shovel plate; 121. Connecting plate; 122. End sealing plate; q. Shovel cavity; s. Shovel surface; x. Adsorption port; M. Comb tool; r. Comb edge; m. Tool body; 13. Floating roller group; 130. Floating roller; 14. Shaping roller group; 140. Shaping roller; 2. Waste chip recovery unit; 20. Leakage receiving assembly; 200. Leakage receiving bottom plate; 201. Leakage hopper; 21. Negative pressure collection assembly; 210. Negative pressure hopper; 211. Separator; 212. Dust collector; n. Parapet plate; 22. Collection assembly; 220. Circular conveyor belt group; d1. First conveyor belt; d2. Second conveyor belt; 221. Collection hopper. Detailed Implementation

[0029] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0030] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0031] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0032] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0033] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0034] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0035] like Figures 1 to 8As shown, the backsheet removal equipment involved in this embodiment includes a cutting unit 1 and a waste recycling unit 2. The cutting unit 1 includes a transmission roller group 10, a main cutting component 11, an auxiliary cutting component 12, a floating roller group 13, and a shaping roller group 14. The waste recycling unit 2 includes a leakage receiving component 20, a negative pressure collection component 21, and a material collection component 22 arranged below the transmission roller group 10. The negative pressure collection component 21 is based on negative pressure to assist the cutting process and break down the waste from the detached battery cells.

[0036] Specifically, the transfer roller group 10 includes multiple transfer rollers 100 arranged side by side and rotating in the same direction, and the top surfaces of the multiple transfer rollers 100 form a flush transfer surface. The main cutting assembly 11 is located above the transfer surface and forms the main cutting channel; the auxiliary cutting assembly 12 is located behind the main cutting assembly 11 and forms the auxiliary cutting channel with the transfer surface.

[0037] In some specific embodiments, the main cutting component 11 includes a plurality of main cutting tools 110 distributed sequentially at intervals along the transmission direction of the photovoltaic module, wherein the plurality of main cutting tools 110 form a cutting area based on the cooperation of partitioning or layering to cover the width of the entire backsheet layer, and the cutting amount used for partitioning is equal to the backsheet layer thickness, and the total cutting amount used for layering is equal to the backsheet layer thickness.

[0038] Each main cutting tool 110 is a hob, which has multiple inserts arranged side by side and spaced apart on the roller, with each insert having an equal width and spacing. By employing staggered and complementary hobbing cutters to cut the entire width of the photovoltaic module, the staggered layout and sequential cutting can mutually limit lateral displacement of the photovoltaic module, effectively suppressing warping, bending, and edge tearing. Alternatively, the cutting areas formed by each main cutting tool 110 have equal width, and the cutting amount is equal to the backsheet layer thickness. Multiple main cutting tools 110 are staggered and complementary in the width direction of the backsheet layer. In short, a zoned processing method is adopted, first grooving, then cutting to achieve comprehensive removal. Specifically, each main cutting tool 110 uses multiple sets of disc cutters (disc cutters), arranged back and forth along the feed direction, and staggered and complementary in the axial (width direction), so that the cutting areas of each set of disc cutters jointly cover the entire width of the photovoltaic module, thereby achieving seamless connection of cutting trajectories between adjacent disc cutters and avoiding residue or overcutting. At the same time, based on the different cutting directions of each row of disc cutters, the lateral stress is mutually canceled, thereby significantly reducing the total lateral bending moment applied to the backsheet and effectively suppressing warping, bending, and edge tearing.

[0039] Alternatively, each main cutting tool 110 can be a wide hob with continuous cutting edges covering the entire backing plate layer, and the sum of the cutting amounts formed by each hob is equal to the thickness of the backing plate layer. By adopting a layered cutting method to gradually remove the backing plate, this method not only generates less lateral stress on the component, but also distributes the total cutting depth according to a preset ratio to multiple wide hobs with continuous cutting edges covering the entire width of the backing plate layer. This significantly reduces the instantaneous cutting area and peak cutting force of each cut, and the resultant force direction is closer to the feed direction, thereby fundamentally suppressing the risk of lateral slippage, elastic rebound, bending warping, and edge tearing of the backing plate. At the same time, since the cutting depth shared by each hob is relatively uniform and constant, the cutting load fluctuation is small, the impact load is reduced, the tool wear rate is more predictable, and the cutting edge life is extended. In addition, the wide hob completes the full-width cutting in one pass without the need for multiple tool passes and docking, resulting in high processing efficiency, almost elimination of tool marks and step defects, and the final obtained cross-section straightness, parallelism, and surface integrity can all reach a high level.

[0040] In short, regardless of whether partitioned cutting or layered cutting is used, the resulting debris is scattered on the surface of the battery cell, and the remaining debris is scattered to the waste recycling unit 2 below.

[0041] In some specific embodiments, the auxiliary cutting component 12 includes a scraper D and a comb-tooth cutter M. The scraper D includes a bottom scraper plate 120, a connecting plate 121, and an end sealing plate 122. The side of the bottom scraper plate 120 near the main cutting component 11 forms a scraping surface s. The connecting plate 121 is located on the opposite side of the scraping surface s and is fixed to the negative pressure collection component 21. The end sealing plate 122 connects the opposite ends of the bottom scraper plate 120 and the connecting plate 121 and fixes them to the negative pressure collection component 21 to form a scraping cavity q. The scraping cavity q extends along the width direction of the photovoltaic module. The scraping surface s and the negative pressure collection component 21 are open to form an adsorption port x. When the scraping surface s scrapes the surface of the solar cell, the waste enters the scraping cavity q from the adsorption port x.

[0042] In this example, a transfer roller 10 is positioned directly below the bottom scraper plate 120. This transfer roller is a aligning transfer roller, where the supporting force generated by the aligning transfer roller and the vertical stress generated by the bottom scraper plate 120 are in dynamic equilibrium. The current position, formed by scraping and support, is in a state of force equilibrium in the vertical direction, eliminating warping and bending of the photovoltaic module caused by the scraping action. The scraping surface s is inclined from bottom to top, and the bottom scraper plate 120 presses flat against the surface of the solar cell. This inclined scraping surface design not only guides the scraped debris into the scraping cavity but also creates a cutting edge that can completely remove residual debris or debris remaining on the surface of the solar cell. The teeth of the comb-tooth cutter M are spaced side-by-side along the width of the photovoltaic module. The comb-tooth cutter M performs the crushing action, preventing large debris from failing to detach smoothly from the solar cell surface and reducing the probability of material mixing caused by debris. The comb-tooth cutter M comprises multiple cutter bodies m spaced apart along the length of the shovel cavity. A comb tooth groove is formed between adjacent cutter bodies m. The projection of each cutter body m onto the thickness of the bottom shovel plate and connecting plate is an isosceles triangle. The comb tooth edges r formed by each cutter body m extend obliquely from bottom to top. The shovel surface s and the inclination angle of each comb tooth edge r are equal. The shoveled waste chips move gradually inward relative to the comb tooth edges as the negative pressure flow proceeds, facilitating the disintegration of large-volume blocky or strip-shaped waste chips. Each comb tooth edge r and the shovel surface s are coplanar, meaning that the plane formed by the aligned comb tooth edges and the shovel surface are in the same plane. The greatest advantage of this design is that it coordinates shoveling and cutting, preventing waste chips from entangled in the comb tooth edges, improving disintegration efficiency and quality, and is more conducive to disintegrating large-volume blocky or strip-shaped waste chips under negative pressure. The upper end of each comb tooth edge r is located between the top edge of the suction port and the top edge of the connecting plate. Based on the angle and position layout, the volume of the shovel chamber increases vertically from bottom to top, which not only facilitates the smooth passage of the crushed waste and the negative pressure mixed airflow, but also, in conjunction with the negative pressure, makes it more conducive to the crushing of waste and the adsorption of suspended waste particles.

[0043] In this example, the floating roller group 13 includes multiple floating rollers 130 arranged between multiple sets of main cutting tools 110 and between the main cutting tools 110 and the auxiliary cutting assembly 12; the shaping roller group 14 includes shaping rollers 140 located on both sides of the auxiliary cutting assembly 12, wherein the floating rollers 130 maintain elastic downward pressure to form rolling pressure, and the distance between the shaping rollers 140 and the lower aligned transfer rollers 10 is equal to the thickness of the photovoltaic module after removing the backsheet, and the distance is adjusted according to the thickness of the photovoltaic module. Based on the floating rollers 130 maintaining elastic downward pressure, continuous rolling pressure is applied to the module to reduce the offset and warping of the module during the cutting process; the gap between the shaping rollers 140 and the lower aligned transfer rollers 10 is precisely set to the thickness of the photovoltaic module after removing the backsheet, and this gap can be flexibly adjusted according to the thickness of the module. At the same time, under the combined action of the continuous rolling pressure of the floating rollers 130 and the precise rolling pressure conveying of the shaping rollers 140, not only is the residual warping and thickness deviation caused by auxiliary cutting eliminated, but the flatness, dimensional consistency and edge quality of the module are further guaranteed.

[0044] In this example, the waste collection assembly 20 includes a waste collection base plate 200 and a receiving hopper 201 extending forward and downward from the front end of the waste collection base plate 200. The waste collection area formed by the receiving hopper 201 covers part or all of the cutting area and the negative pressure scraping area. Based on the covering-type waste collection and guidance, scattered waste is collected and gathered, thus facilitating waste collection. The waste collection base plate 200 is inclined from back to front and downward, further facilitating the collection and gathering of debris.

[0045] In some specific embodiments, the negative pressure collection assembly 21 includes a negative pressure hopper 210, a separator 211, and a dust collector 212. A connecting plate 121 and an end-sealing plate are fixed to the negative pressure hopper 210, and a baffle plate n is arranged above the shovel surface s of the negative pressure hopper 210. An opening x is formed between the baffle plate n and the shovel surface s. Material is drawn in based on the negative pressure generated by the separator, followed by solid-gas separation. The separated solid waste is collected by the negative pressure, and the separated waste gas is discharged after entering the dust collector.

[0046] In this example, the negative pressure hopper 210 is flat in the front-to-back direction, and the negative pressure cavity gradually decreases in size from bottom to top. Using a flat hopper not only facilitates negative pressure adsorption but also reduces space requirements and improves the layout of other components. The separator 211 is a cyclone separator. It uses centrifugal force for separation and is a standard outsourced product. The dust collector 212 is a bag filter dust collector. It is mainly used for exhaust gas purification and is also a standard outsourced product.

[0047] In some specific embodiments, the collecting assembly 22 uses a ring conveyor belt to connect the leakage collection point and the negative pressure collection point. Specifically, the collecting assembly 22 includes a ring conveyor belt group 220 and a collecting hopper 221. The ring conveyor belt group 220 includes a first conveyor belt d1 and a second conveyor belt d2 connected from opposite ends. The first conveyor belt d1 is horizontally positioned and connects the leakage collection point and the negative pressure collection point. The second conveyor belt d2 is inclined from bottom to top, with its lower end connected to the first conveyor belt d1 and the collecting hopper 221 installed at its upper end. The discharge port of the collecting hopper 221 constitutes a convergence point. Based on the convergence point setup, only the receiving frame needs to be used; operators can periodically change the frame, saving labor costs and promoting the intelligent development of backplate removal.

[0048] The backsheet cutting and waste recycling process for photovoltaic modules in this embodiment includes the following steps: S1. Main Cutter The main cutting channel is formed by the main cutting component and the transfer roller group. The main cutting channel is distributed at intervals in the transmission direction of the photovoltaic module and forms two main cutting zones. The glass layer of the photovoltaic module is attached to the transfer roller surface and the back sheet layer is facing upwards. The back sheet layer is removed by the partitioning or layering cooperation of the two main cutting zones. S2. Auxiliary cutting The auxiliary cutting channel is formed by the auxiliary cutting component and the conveying roller group. The auxiliary cutting component used in the auxiliary cutting channel is based on the reverse scraping and combing and breaking in the opposite direction of the photovoltaic module's transmission direction. It assists the main cutting with lateral restraint and warping restraint, and removes the waste residue or residual waste on the surface of the cell. Under the negative pressure cooperation formed by the negative pressure collection component along the reverse scraping angle, the auxiliary cutting component scrapes and breaks the waste synchronously. The auxiliary cutting component includes scraping blades and combing blades. S3. Debris Collection First, the waste debris scattered from the main and auxiliary cutting processes is collected and transferred forward and downward along the photovoltaic module's transmission direction, with the end of the transfer forming a leakage collection point. Second, the negative pressure collection module is connected to the auxiliary cutting channel. The waste debris and suspended particles after being cut by the auxiliary cutting module are collected upward along the groove area formed by the angle of the shovel and the comb teeth by the negative pressure airflow to the negative pressure hopper. Then, the waste debris is separated by solid-gas separation, and the separated waste debris converges, with the outlet forming a negative pressure collection point. Finally, a material collection module is used to connect the leakage collection point and the negative pressure collection point, and the collected waste debris is concentrated at the convergence point.

[0049] In some specific embodiments, each segment of the main cutting area in step S1 is equipped with a main cutting tool. The main cutting area formed by the cooperation of multiple main cutting tools covers the width of the photovoltaic module, and the total cutting amount is equal to the thickness of the backsheet layer; or, the main cutting area formed by the cooperation of multiple main cutting tools covers the width of the photovoltaic module, and the cutting amount of each main cutting tool is equal to the thickness of the backsheet layer. At the same time, the multiple main cutting areas are staggered and complementary in the width direction of the backsheet layer. In step S2, the angle between the reverse scraper formed by the auxiliary cutting component and the surface of the battery cell is β, where 0°≤β<90°. Generally, 0°≤β≤15°. The smaller the angle between the scraper and the surface of the battery cell, the better. In this example, β=0° (of course, β=5° or β=10°), indicating that the scraping is performed entirely along the horizontal direction. On the one hand, this not only avoids stress in the vertical direction that could cause scratches on the surface of the battery cell, but also improves cutting and transmission stability based on the constraints formed by the flat scraper. On the other hand, the negative pressure adsorption guide formed not only eliminates the vertical stress caused by upward adsorption, but also more smoothly draws debris into the adsorption port.

[0050] The present invention has been described in detail above, with the aim of enabling those skilled in the art to understand and implement the invention. However, this description should not be construed as limiting the scope of protection of the invention. All equivalent changes or modifications made in accordance with the spirit and essence of the invention should be included within the scope of protection of the invention.

Claims

1. A backsheet cutting and waste recycling process for photovoltaic modules, wherein the backsheet removal equipment comprises a cutting unit and a waste recycling unit, characterized in that, The cutting unit includes a set of side-by-side and co-rotating transfer rollers, a main cutting assembly, and an auxiliary cutting assembly. The waste recycling unit includes a leakage receiving assembly, a negative pressure collection assembly, and a material collection assembly located below the transfer rollers. The negative pressure collection assembly uses negative pressure to assist the auxiliary cutting process to break down the waste debris from the detached solar cells, and includes the following steps: S1. Main Cutter The main cutting channel is formed by the main cutting component and the transfer roller group. The main cutting channel is distributed at intervals in the transmission direction of the photovoltaic module and forms multiple main cutting zones. The glass layer of the photovoltaic module is attached to the transfer roller surface and the back sheet layer is facing upwards and passes through each main cutting zone in sequence. The back sheet layer is removed by the partitioning or layering of multiple main cutting zones. S2. Auxiliary cutting The auxiliary cutting channel is formed by the auxiliary cutting component and the conveying roller group. The auxiliary cutting component used in the auxiliary cutting channel is based on the reverse scraping and combing and breaking in the opposite direction of the photovoltaic module's transmission direction. It assists the main cutting with lateral restraint and warping restraint, and removes the waste residue or residual waste on the surface of the cell. Under the negative pressure cooperation formed by the negative pressure collection component along the reverse scraping angle, the auxiliary cutting component scrapes and breaks the waste synchronously. The auxiliary cutting component includes scraping blades and combing blades. S3. Debris Collection First, the waste debris scattered from the main and auxiliary cutting processes is collected and transferred forward and downward along the photovoltaic module's transmission direction, with the end of the transfer forming a leakage collection point. Second, the negative pressure collection module is connected to the auxiliary cutting channel. The waste debris and suspended particles after being cut by the auxiliary cutting module are collected upward along the groove area formed by the angle of the shovel and the comb teeth by the negative pressure airflow to the negative pressure hopper. Then, the waste debris is separated by solid-gas separation, and the separated waste debris converges, with the outlet forming a negative pressure collection point. Finally, a material collection module is used to connect the leakage collection point and the negative pressure collection point, and the collected waste debris is concentrated at the convergence point.

2. The photovoltaic module backsheet cutting and waste recycling process according to claim 1, characterized in that, In step S1, each main cutting area is equipped with a main cutting tool. The main cutting area formed by the cooperation of multiple main cutting tools covers the width of the photovoltaic module, and the total cutting depth is equal to the thickness of the backsheet layer; or, the main cutting area formed by the cooperation of multiple main cutting tools covers the width of the photovoltaic module, and the cutting depth of each main cutting tool is equal to the thickness of the backsheet layer. At the same time, the multiple main cutting areas are staggered and complementary in the width direction of the backsheet layer.

3. The backsheet cutting and waste recycling process for photovoltaic modules according to claim 2, characterized in that, The transfer roller assembly includes multiple transfer rollers arranged side by side and spaced apart, with the top surfaces of the multiple transfer rollers forming a transfer surface. Each main cutting tool has a transfer roller positioned directly below it, and the transfer rollers are alignment transfer rollers. The supporting force formed by the alignment transfer rollers and the vertical stress formed by cutting are in a state of dynamic equilibrium.

4. The backsheet cutting and waste recycling process for photovoltaic modules according to claim 1, characterized in that, In step S2, the angle between the spade formed by the spade tool and the surface of the battery cell is β, where 0°≤β<90°.

5. The backsheet cutting and waste recycling process for photovoltaic modules according to claim 1, characterized in that, The scraper includes a bottom scraper plate, a connecting plate, and an end sealing plate. The bottom scraper plate forms a scraping surface on the side near the main scraping component. The connecting plate is located on the opposite side of the scraping surface and is fixed to the negative pressure collection component. The end sealing plate connects the bottom scraper plate and the connecting plate at opposite ends and fixes them to the negative pressure collection component to form a scraping cavity. The scraping cavity extends along the width direction of the photovoltaic module. The opening between the scraping surface and the negative pressure collection component forms an adsorption port. When the scraping surface scrapes the surface of the solar cell, the waste enters the scraping cavity from the adsorption port.

6. The backsheet cutting and waste recycling process for photovoltaic modules according to claim 5, characterized in that, The shovel surface is inclined from bottom to top, and the bottom shovel plate presses flat on the surface of the battery cell.

7. The backsheet cutting and waste recycling process for photovoltaic modules according to claim 6, characterized in that, The tooth grooves of the comb cutter are arranged side by side and spaced apart in the width direction of the photovoltaic module. The comb cutter includes multiple cutter bodies spaced apart along the length direction of the shovel cavity. A comb groove is formed between two adjacent cutter bodies. The projection of each cutter body in the thickness direction of the bottom shovel plate and the connecting plate is triangular. The comb edge formed by each cutter body extends obliquely from bottom to top.

8. The backsheet cutting and waste recycling process for photovoltaic modules according to claim 6, characterized in that, The triangle is an isosceles triangle; and / or, the inclination angles of the shovel surface and each comb tooth blade are equal; and / or, each comb tooth blade and the shovel surface are coplanar; and / or, the upper end of each comb tooth blade is located between the top edge of the suction port and the top edge of the connecting plate.

9. The backsheet cutting and waste recycling process for photovoltaic modules according to claim 5, characterized in that, The conveyor roller assembly includes multiple conveyor rollers arranged side-by-side and spaced apart. The top surfaces of the multiple conveyor rollers form a conveyor surface. A conveyor roller is positioned directly below the bottom shovel plate and is an aligned conveyor roller. The supporting force formed by the aligned conveyor roller and the vertical stress formed by the bottom shovel plate are in a state of dynamic equilibrium. And / or, the negative pressure collection assembly includes a negative pressure hopper, a separator, and a dust collector. A connecting plate and an end sealing plate are fixed to the negative pressure hopper, and a baffle plate is arranged above the shovel surface of the negative pressure hopper. An opening is formed between the baffle plate and the shovel surface to form an adsorption port. The separator is a cyclone separator. And / or, the dust collector is a bag filter dust collector.

10. The backsheet cutting and waste recycling process for photovoltaic modules according to claim 1, characterized in that, In step S3, the collecting assembly uses an annular conveyor belt to connect the leak collection point and the negative pressure collection point; and / or, the collecting assembly includes an annular conveyor belt group and a collecting hopper, wherein the annular conveyor belt group includes a first conveyor belt and a second conveyor belt connected from opposite ends, the first conveyor belt is horizontally arranged and connects the leak collection point and the negative pressure collection point; the second conveyor belt is inclined from bottom to top, and its lower end is connected to the first conveyor belt, and the upper end is equipped with a collecting hopper, the discharge port of the collecting hopper forming a convergence point.

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