Method for green separation of waste photovoltaic modules

Abstract

The invention provides a method for green separation of a waste photovoltaic module, aims to solve the problems of high energy consumption, environmental pollution and low recovery efficiency in the existing recovery method, and effectively separates an EVA (Ethylene Vinyl Acetate) adhesive film, a battery piece, a glass layer and a back plate in the waste photovoltaic module through multiple synergistic effects and combined use of vegetable oil and reaction enzyme. Comprising the following steps: firstly, pretreating the waste photovoltaic module and cutting to obtain a sample containing an EVA (Ethylene Vinyl Acetate) adhesive film; soaking the sample in vegetable oil, softening the adhesive film by using the dissolution and permeation effects of the vegetable oil, and reducing the adhesive force between the adhesive film and the battery piece and the glass layer; then adding a reaction enzyme, such as lipase, to further accelerate the softening of the adhesive film and promote the separation; finally, all the materials are separated through a mechanical means, and residual vegetable oil, reaction enzymes and adhesive films are removed through ethyl alcohol cleaning. The method has the advantages of environmental protection, low cost and high efficiency, the recovery rate reaches 95% or above, the purity of the recovered material is high, the environmental pollution is reduced, and the recycling value of the waste photovoltaic module is improved.

Description

Technical Field

[0001] The invention relates to the technical field of photovoltaic component recycling, and in particular to a method for green separation of waste photovoltaic components. Background Art

[0002] The service life of photovoltaic modules is usually 20 to 25 years, which means that in the next few years, a large number of waste photovoltaic modules will gradually enter the scrap period. Waste photovoltaic modules contain a large amount of valuable materials such as high-purity silicon, silver, and aluminum. If they cannot be effectively recycled, it will not only lead to a waste of resources, but also cause environmental pollution. Therefore, the development of an efficient and environmentally friendly recycling technology has important economic and environmental significance.

[0003] At present, the recycling methods of waste photovoltaic modules mainly include mechanical treatment, thermal treatment and chemical treatment. Traditional mechanical treatment methods usually include crushing and screening, which can effectively recycle materials such as glass, aluminum frames and plastics. However, since high-purity cells cannot be effectively separated, the recycled silicon materials often have more impurities and low recycling efficiency. In addition, the mechanical treatment process is also accompanied by dust, noise and other problems, and the separation effect on composite materials is not ideal.

[0004] The thermal treatment method removes the organic part through high-temperature incineration. Although this method can recover high-purity metals and silicon materials, it has high energy consumption and produces a large amount of harmful gases and waste gas during high-temperature operation, which not only pollutes the environment, but also produces a large amount of carbon emissions, further increasing the environmental burden. During the separation process, the pyrolysis method effectively separates organic and inorganic substances through high-temperature treatment, but it also faces problems such as high energy consumption and high equipment costs, and the waste gas and harmful substances produced also affect its large-scale application.

[0005] Although chemical treatment methods can achieve a higher recovery rate, they usually use strong acids, strong bases or organic solvents. These chemical solvents may pollute the environment during the treatment process, and their operation process also has certain safety risks. Therefore, although the existing technology has made some progress in recycling photovoltaic modules, the existing recycling methods still face problems such as high energy consumption, environmental pollution and low recycling efficiency, and it is necessary to find more efficient, safe and environmentally friendly solutions. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a method for green separation of waste photovoltaic modules to solve the problems of high energy consumption, environmental pollution and low recycling efficiency existing in the prior art, especially for the effective separation of EVA film from battery cells, glass and other materials. The existing recycling methods usually use strong acid, strong alkali or high-temperature pyrolysis and other treatment methods. These methods not only pollute the environment, but may also cause damage to the recycled materials.

[0007] In order to overcome the above defects of the prior art, the present invention provides a method for green separation of waste photovoltaic modules, comprising the following steps: S1: pre-treating waste photovoltaic modules to obtain waste photovoltaic module laminates; S2: cutting the waste photovoltaic module laminate obtained in step S1 to obtain a photovoltaic module laminate sample, wherein the photovoltaic module laminate sample consists of an EVA film, a battery cell, a glass layer and a back sheet; S3: Soaking the photovoltaic module laminate sample in vegetable oil, wherein the mass ratio of the vegetable oil to the photovoltaic module laminate sample is (2-5):1, and the vegetable oil softens the EVA film of the sample through dissolution and penetration, thereby reducing the adhesion between the film and the cell sheet and the glass layer; S4: adding a reaction enzyme to the vegetable oil to obtain a reaction system of the reaction enzyme and the vegetable oil, wherein the enzyme includes one or more of lipase, cellulase, and protease, and the softening of the EVA film is further accelerated by the catalytic action of the reaction enzyme, and the separation of the EVA film from other materials is promoted after soaking; S5: Separating the photovoltaic module laminate sample processed in step S4 to complete the separation of waste photovoltaic modules.

[0008] Compared with the prior art, the green separation method of waste photovoltaic modules of the present invention has the following advantages: Environmental protection: The present invention adopts the combined action of vegetable oil and reaction enzyme. Vegetable oil is a natural solvent with low toxicity and biodegradability, which avoids the environmental pollution problems caused by traditional solvents and high-temperature treatment methods. By reducing the use of chemical solvents, the harm to the environment is reduced;

[0009] High efficiency: Vegetable oil effectively softens the EVA film through dissolution and penetration, reducing the adhesion between the film and the battery cell and glass layer. The addition of the reaction enzyme further accelerates the softening and separation of the film, significantly improving the separation efficiency and reducing the time required; Safety: The combined use of enzyme and vegetable oil greatly reduces the hazards of chemical solvents, while avoiding the use of high temperature and toxic solvents, protecting the safety of operators and reducing potential safety hazards in the recycling process; Low cost: Compared with traditional chemical solvents and pyrolysis methods, vegetable oil and enzymes have lower costs and are used in smaller quantities, which reduces the investment in the recycling process and helps reduce the cost of the entire recycling process; Through the method of the present invention, efficient separation of EVA film from battery cells, glass, back panels and other parts in waste photovoltaic modules is achieved, and the recovery rate reaches more than 95%. There is almost no residual film on the surface of the recycled battery cells and glass. This method not only improves the purity of the recycled materials, but also reduces the negative impact on the environment and operators, and has important economic and environmental value.

[0010] In a possible implementation manner, the pre-processing includes: removing aluminum frames and junction boxes of waste photovoltaic modules.

[0011] Compared with the prior art, the above technical solution adopts aluminum frames and junction boxes that usually contain metal, plastic and other parts that are not easy to separate from other materials, and these parts may interfere with the recycling equipment during the recycling process, increasing the wear and tear of the equipment and the complexity of operation. By removing these parts first, it is possible to avoid the influence of unnecessary impurities on the subsequent recycling process, reduce obstacles during mechanical separation, and make the separation process of remaining materials more efficient.

[0012] In a possible implementation, in step S3, the soaking temperature is 40-60° C., and the soaking time is 1-3 hours.

[0013] Compared with the prior art, by adopting the above technical scheme, the solubility of vegetable oil is fully exerted within the temperature range of 40-60°C, while at the same time it will not be too high to cause volatilization of vegetable oil or other adverse reactions. When the temperature is too low, the permeability of vegetable oil is insufficient, which may lead to unclear softening effect of the film and reduced separation efficiency; while too high a temperature may cause excessive reaction or consumption of vegetable oil, resulting in excessive decomposition of the film, generation of unnecessary by-products, and affecting the purity of the recycled material. Therefore, setting this temperature range ensures that vegetable oil can penetrate the EVA film in the best state and soften the film, and achieve the ideal separation effect through 1-3 hours of immersion.

[0014] In a possible implementation, in step S4, the mass concentration of the reaction enzyme in the reaction system is 1-5%.

[0015] Compared with the existing technology, the above technical scheme can effectively enhance the catalytic effect of enzymes in vegetable oils, thereby accelerating the softening and separation of EVA films: the mass concentration of the reaction enzyme is set between 1-5%, which can ensure that the activity of the reaction enzyme is fully exerted while avoiding excessive concentration leading to excessive reaction or excessive use of the reaction enzyme; too low a concentration may cause the reaction speed to be too slow, and it is impossible to achieve the ideal separation effect in a short time, while too high a concentration may produce unnecessary side effects, such as excessive degradation of the film or adverse reactions with other materials, thereby affecting the integrity of the recycled material.

[0016] In a possible implementation, in step S4, the reaction enzyme is lipase.

[0017] Compared with the prior art, the above-mentioned technical solution uses lipase as a catalyst to more effectively decompose the fat components in the EVA film, thereby accelerating the softening of the film and its separation from other materials (such as battery cells, glass and back panels); compared with other types of reaction enzymes, lipase has higher specificity and better catalytic efficiency when processing EVA films containing fat and non-polar components. It can efficiently decompose the fat and oil components in the film, reduce the adhesion between the film and the battery cells and glass, thereby making the separation process smoother. Compared with other enzymes, lipase produces fewer by-products during the decomposition process, which helps to ensure the purity of the recycled materials and further achieves the "green" effect.

[0018] In a possible implementation, in step S4, the soaking temperature is 40-60° C., and the reaction time is 2 to 10 hours.

[0019] Compared with the prior art, the above technical solution can significantly optimize the efficiency of the enzyme-catalyzed reaction. The temperature is set between 40-60°C to ensure the optimal activity of the enzyme, while avoiding damage to the enzyme or unnecessary reactions caused by excessively high temperatures. Lower temperatures can effectively control the reaction rate of the enzyme and prevent excessively rapid decomposition reactions from producing by-products, while higher temperatures can increase the overall reaction rate and accelerate the softening of the film. The reaction time is set to 2 to 10 hours, which can ensure that the enzyme can fully function and further promote the separation of the film from the battery cell and glass.

[0020] In a possible implementation, in step S4, the pH of the reaction system is 5-7, and during the reaction in step S4, the pH of the reaction system is adjusted by using a phosphate or citric acid buffer.

[0021] Compared with the prior art, the above technical solution can more accurately control the reaction conditions, thereby optimizing the catalytic effect of the reaction enzyme. The activity of reaction enzymes such as lipase usually depends on the appropriate pH environment. Too high or too low pH values ​​may lead to the inactivation of the reaction enzyme or reduce the catalytic efficiency. By controlling the pH of the reaction system within the range of 5-7, the optimal activity state of the reaction enzyme is ensured, avoiding damage to the structure and function of the reaction enzyme caused by too high or too low pH.

[0022] In a possible embodiment, in step S5, the operation of separating the photovoltaic module laminate sample processed in step S4 includes: separating the EVA film, battery cell, glass layer and backplane by mechanical means, and washing the separated battery cell and glass with ethanol to remove residual vegetable oil, enzyme and film.

[0023] Compared with the existing technology, the above technical solution uses physical force or appropriate tools (including vibration, ultrasound or special mechanical devices) to directly act on the film through mechanical separation, so that the film falls off from the surface of the battery cell, glass and backplane, and can efficiently separate the various components without destroying the recycled materials; and the use of ethanol for cleaning effectively removes residual vegetable oil, reaction enzyme and film. Ethanol has good dissolving ability and can clean out impurities in grease and film, ensuring that there is almost no residue on the surface of the battery cell and glass, thereby improving the purity of the material. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of the structure of the photovoltaic module laminate sample before separation; Figure 2 This is a frontal photograph of the photovoltaic laminate sample before separation; Figure 3 This is a photo of the glass, back sheet, silicon cell and EVA film obtained after the laminated parts of waste photovoltaic modules are separated; ( Figure 3 Already marked) Figure 1 Among them, 1. Glass layer; 2. EVA film; 3. Battery cell; 4. Back panel. DETAILED DESCRIPTION

[0025] First, those skilled in the art should understand that these implementations are only used to explain the technical principles of the embodiments of the present invention, and are not intended to limit the protection scope of the embodiments of the present invention. Those skilled in the art can make adjustments to them as needed to adapt to specific application scenarios.

[0026] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" 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 or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0027] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0028] The present invention provides a method for green separation of waste photovoltaic modules, comprising the following steps: S1: Pre-treating waste photovoltaic modules to obtain waste photovoltaic module laminates, such as Figure 1 As shown, Figure 1 Schematic diagram of the structure of the photovoltaic module laminate sample before separation, and the waste photovoltaic module laminate is obtained. Figure 2 This is a frontal photograph of the photovoltaic laminate sample before separation; S2: cutting the waste photovoltaic module laminate obtained in step S1 to obtain a photovoltaic module laminate sample, wherein the photovoltaic module laminate sample consists of an EVA film 2, a battery cell 3, a glass layer 1 and a back sheet 4; S3: Soaking the photovoltaic module laminate sample in vegetable oil, wherein the mass ratio of the vegetable oil to the photovoltaic module laminate sample is (2-5):1, and the vegetable oil softens the EVA film 2 of the sample through dissolution and penetration, thereby reducing the adhesion between the film and the battery cell 3 and the glass layer 1; S4: adding a reaction enzyme to the vegetable oil to obtain a reaction system of the reaction enzyme and the vegetable oil, wherein the reaction enzyme includes one or more of lipase, cellulase, and protease, and the softening of the EVA film 2 is further accelerated by the catalytic action of the reaction enzyme, and the separation of the EVA film 2 from other materials is promoted after soaking; S5: Separating the photovoltaic module laminate sample after the treatment in step S4 to complete the separation of waste photovoltaic modules, such as Figure 3 As shown, Figure 3 This is a photo of the glass layer 1, back panel 4, silicon cell 3 and EVA film 2 obtained after separation of waste photovoltaic module laminates.

[0029] As a preferred solution, in step S1, the pretreatment includes: removing the aluminum frame and junction box of the waste photovoltaic modules.

[0030] As a preferred solution, in step S3, the soaking temperature is 40-60° C., and the soaking time is 1-3 hours.

[0031] As a preferred solution, in step S4, the mass concentration of the reaction enzyme in the reaction system is 1-5%.

[0032] As a preferred solution, in step S4, the reaction enzyme is lipase.

[0033] As a preferred solution, in step S4, the soaking temperature is 40-60° C., and the reaction time is 2 to 10 hours.

[0034] As a preferred solution, in step S4, the pH of the reaction system is 5-7, and during the reaction of step S4, the pH value of the reaction system is adjusted by using a phosphate or citric acid buffer.

[0035] As a preferred scheme, in step S5, the operation of separating the photovoltaic module laminate sample processed in step S4 includes: separating the EVA film 2, the battery cell 3, the glass layer 1 and the back panel 4 by mechanical means, and using ethanol to clean the separated battery cell 3 and glass 1 to remove residual vegetable oil, reaction enzyme and film.

[0036] The technical principle of the present invention is based on the synergistic effect of multiple factors, and aims to provide an efficient, green and low-cost method for separating waste photovoltaic modules through the combined action of vegetable oil and reaction enzyme. Specifically, the present invention utilizes the interaction between vegetable oil and reaction enzyme at different reaction stages, thereby significantly improving the efficiency and accuracy of the recycling process. The following is an analysis of each step of the present invention:

[0037] First, as a natural solvent, the vegetable oil molecules can penetrate and soften the fat and non-polar components in the EVA film 2. The vegetable oil destroys the adhesion between the EVA film 2 and the battery cell 3 and the glass 1 through dissolution, laying the foundation for subsequent separation. The role of vegetable oil is to soften the film, making it brittle or loose, providing a more favorable environment for the catalytic action of the reaction enzyme;

[0038] Subsequently, the reaction enzyme (such as lipase, cellulase, etc.) further accelerates the softening and dissolution of the EVA film 2 by catalyzing the decomposition of fat and oil components in the film. Lipase is particularly suitable for decomposing the fat components in the film, and it has high selectivity and efficiency in the hydrolysis process of the film, avoiding the generation of excessive by-products. The catalytic effect of the enzyme and the dissolution effect of the vegetable oil are highly synergistic. The reaction enzyme enhances the permeability of the vegetable oil through the catalytic reaction, so that the components in the film are decomposed faster and more thoroughly, thereby making the separation of the EVA film 2 more efficient and accurate. Based on the synergistic effect of the above two methods, the separation process uses mechanical means to physically separate the EVA film 2, the battery cell 3, the glass 1 and the back panel 4. This physical separation process can ensure that the bonding force between the film and other materials is fully weakened, and can effectively avoid the damage to the recycled materials that may be caused by traditional methods. In addition, the residues of vegetable oil, reaction enzyme and film are removed by ethanol washing, which further ensures the purity of the recycled materials. Finally, the combined effect of vegetable oil, reaction enzyme and mechanical separation makes the entire separation process not only efficient, but also maintains the integrity and purity of the recycled materials. The method of the present invention avoids the use of high temperature and strong acid and alkali chemicals, thereby significantly reducing energy consumption and environmental pollution, conforming to the concept of green environmental protection recycling, and the synergistic effect of each link makes the recycling process more efficient, environmentally friendly and economical, thereby improving the recycling efficiency and reuse value of waste photovoltaic modules as a whole.

[0039] The following is a further explanation of the above technical solution of the present invention in combination with actual data: Embodiment 1: This embodiment provides a method for green separation of waste photovoltaic modules, and the specific operations are as follows: S1: Pre-treatment of waste photovoltaic modules First, the aluminum frame and the junction box of the waste photovoltaic module are removed to obtain the waste photovoltaic module laminate. In this step, the aluminum frame and the junction box are removed from the photovoltaic module by physical means, and the obtained waste photovoltaic module laminate includes EVA film 2, battery cell 3, glass layer 1 and back plate 4. S2: Cutting of waste photovoltaic module laminates Cutting the waste photovoltaic module laminate obtained in step S1 into photovoltaic module laminate samples of 2 cm×2 cm in size, the obtained photovoltaic module laminate samples include EVA film 2, battery cell 3, glass layer 1 and back sheet 4. The composition of each sample ensures the effective separation of each material in the subsequent processing process;

[0040] S3: Soaking of waste photovoltaic module samples The photovoltaic module laminate sample obtained in step S2 is immersed in vegetable oil; the vegetable oil used is rapeseed oil, and the mass ratio of vegetable oil to photovoltaic module sample is 3:1. The immersion temperature is 45°C and the duration is 1 hour. During the immersion process, the vegetable oil softens the EVA film 2 through dissolution and penetration, and effectively reduces the adhesion between the film and the battery cell 3 and the glass layer 1, preparing for the subsequent separation step;

[0041] S4: Add enzyme and react In step S3, lipase is added, and the mass concentration of lipase is 2%. The pH of the reaction system is adjusted to 6 by citric acid buffer. The immersion reaction lasts for 6 hours, and the reaction temperature is maintained at 45°C. Under the catalytic action of the enzyme, the EVA film 2 is further softened, which promotes the separation of the film from the battery cell 3, the glass layer 1 and the back plate 4.

[0042] S5: Separation and cleaning of waste photovoltaic module materials The sample after processing in step S4 is separated by mechanical means, and the EVA film 2, the battery cell 3, the glass layer 1 and the back plate 4 are separated by appropriate physical tools (such as an ultrasonic cleaning device). The separated battery cell 3 and the glass 1 are cleaned with ethanol to remove the residual vegetable oil, the reaction enzyme and the film. There is almost no residue on the surface of the battery cell 3 and the glass 1 after cleaning, and the purity of the material is high, which ensures the smooth progress of the subsequent recycling process.

[0043] Through the method in this embodiment, the recovery rate of waste photovoltaic modules reaches 96.62%, and there is almost no adhesive film residue on the recovered cells 3 and glass 1, indicating that the green separation method provided by the present invention has high recovery efficiency and material purity.

[0044] Example 2 This embodiment provides a method for green separation of waste photovoltaic modules, and the specific operations are as follows: S1: Pre-treatment of waste photovoltaic modules First, the aluminum frame and the junction box of the waste photovoltaic module are removed to obtain the waste photovoltaic module laminate. In this step, the aluminum frame and the junction box are removed from the photovoltaic module by physical means, and the obtained waste photovoltaic module laminate includes EVA film 2, battery cell 3, glass layer 1 and back plate 4. Figure 1 As shown, it includes a glass layer 1, an EVA film 2, a battery cell 3, an EVA film 2, and a back panel stacked in sequence from top to bottom.

[0045] S2: Cutting of waste photovoltaic module laminates The waste photovoltaic module laminate obtained in step S1 is cut into photovoltaic module laminate samples of 2 cm×2 cm in size, and the obtained photovoltaic module laminate samples include EVA film 2, battery cell 3, glass layer 1 and back sheet 4. The composition of each sample ensures the effective separation of each material in the subsequent processing process.

[0046] S3: Soaking of waste photovoltaic module samples The photovoltaic module laminate sample obtained in step S2 is immersed in vegetable oil; the vegetable oil used is rapeseed oil, and the mass ratio of vegetable oil to photovoltaic module sample is 2:1. The immersion temperature is 40°C and the duration is 1 hour. During the immersion process, the vegetable oil softens the EVA film 2 through dissolution and penetration, and effectively reduces the adhesion between the film and the battery cell 3 and the glass layer 1, preparing for the subsequent separation step.

[0047] S4: Add enzyme and react In step S3, lipase is added, and the mass concentration of lipase is 1%. The pH of the reaction system is adjusted to 5 by citric acid buffer, and the immersion reaction is continued for 2 hours. The reaction temperature is maintained at 40°C. Under the catalytic action of the enzyme, the EVA film 2 is further softened, which promotes the separation of the film from the battery cell 3, the glass layer 1 and the back panel 4.

[0048] S5: Separation and cleaning of waste photovoltaic module materials The sample after processing in step S4 is separated by mechanical means, and the EVA film 2, the battery cell 3, the glass layer 1 and the back plate 4 are separated by appropriate physical tools (such as an ultrasonic cleaning device). The separated battery cell 3 and the glass 1 are cleaned with ethanol to remove the residual vegetable oil, the reaction enzyme and the film. There is almost no residue on the surface of the battery cell 3 and the glass 1 after cleaning, and the purity of the material is high, which ensures the smooth progress of the subsequent recycling process.

[0049] Through the method in this embodiment, the recovery rate of waste photovoltaic modules reaches 94.88%, and there is almost no adhesive film residue on the recovered cells 3 and glass 1, indicating that the green separation method provided by the present invention has high recovery efficiency and material purity.

[0050] Example 3 This embodiment provides a method for green separation of waste photovoltaic modules, and the specific operations are as follows: S1: Pre-treatment of waste photovoltaic modules First, the aluminum frame and junction box of the waste photovoltaic module are removed to obtain the waste photovoltaic module laminate. This step removes the aluminum frame and junction box from the photovoltaic module by physical means. The obtained waste photovoltaic module laminate includes EVA film 2, battery cell 3, glass layer 1 and back panel 4.

[0051] S2: Cutting of waste photovoltaic module laminates The waste photovoltaic module laminate obtained in step S1 is cut into photovoltaic module laminate samples of 2 cm×2 cm in size, and the obtained photovoltaic module laminate samples include EVA film 2, battery cell 3, glass layer 1 and back sheet 4. The composition of each sample ensures the effective separation of each material in the subsequent processing process.

[0052] S3: Soaking of waste photovoltaic module samples The photovoltaic module laminate sample obtained in step S2 is immersed in vegetable oil; the vegetable oil used is rapeseed oil, and the mass ratio of vegetable oil to photovoltaic module sample is 5:1. The immersion temperature is 60°C and the duration is 3 hours. During the immersion process, the vegetable oil softens the EVA film 2 through dissolution and penetration, and effectively reduces the adhesion between the film and the battery cell 3 and the glass layer 1, preparing for the subsequent separation step.

[0053] S4: Add enzyme and react In step S3, lipase is added, and the mass concentration of lipase is 5%. The pH of the reaction system is adjusted to 7 by citric acid buffer. The immersion reaction lasts for 10 hours, and the reaction temperature is maintained at 60°C. Under the catalytic action of the enzyme, the EVA film 2 is further softened, which promotes the separation of the film from the battery cell 3, the glass layer 1 and the back plate 4.

[0054] S5: Separation and cleaning of waste photovoltaic module materials The sample after processing in step S4 is separated by mechanical means, and the EVA film 2, the battery cell 3, the glass layer 1 and the back plate 4 are separated by appropriate physical tools (such as an ultrasonic cleaning device). The separated battery cell 3 and the glass 1 are cleaned with ethanol to remove residual vegetable oil, enzymes and film. There is almost no residue on the surface of the cleaned battery cell 3 and the glass 1, and the purity of the material is high, which ensures the smooth progress of the subsequent recycling process.

[0055] Through the method in this embodiment, the recycling rate of waste photovoltaic modules reaches 96.15%, and there is almost no residual film on the recycled battery cells 3 and glass 1, which proves that the green separation method provided by the present invention can also efficiently separate and recycle materials under different operating conditions.

[0056] Embodiment 4: Example 4 is similar to Example 1, except that the reaction enzyme in step S4 is replaced by cellulase; Through the method of Example 4, the recovery rate of waste photovoltaic modules is 95.15%, and there is almost no adhesive film residue on the recovered cells 3 and glass 1.

[0057] Embodiment 5: Example 5 is similar to Example 1, except that the reaction enzyme in step S4 is replaced by protease; Through the method of Example 5, the recovery rate of waste photovoltaic modules is 95.67%, and there is almost no adhesive film residue on the recovered cells 3 and glass 1.

[0058] Through the above embodiments, it is also further proved that the present invention provides a method for green separation of waste photovoltaic modules, which uses the synergistic effect of vegetable oil and reaction enzyme to successfully solve the problems of low recovery efficiency, high energy consumption and environmental pollution in the prior art; vegetable oil softens the EVA film by dissolution and penetration, reduces the adhesion between the film and the battery sheet and the glass layer, and the addition of the reaction enzyme further accelerates the softening and decomposition of the film, thereby effectively improving the recovery efficiency; in particular, by optimizing the reaction conditions and using lipase as a catalyst, the recovery rate is further improved. Lipase can specifically decompose the fat component in the film, has a higher catalytic efficiency than other reaction enzymes, and can effectively avoid the generation of by-products, ensuring the purity of the recycled material. In addition, by controlling parameters such as immersion temperature, reaction time and pH value, the method of the present invention shows a higher recovery rate under different conditions.

[0059] Therefore, the present invention not only significantly improves the recycling rate of waste photovoltaic modules, but also realizes a low-energy consumption and environmentally friendly recycling process, providing a new and efficient technical solution for the green recycling of waste photovoltaic modules.

[0060] In the description of the embodiments of the present invention, it should be noted that in the description of the present invention, the terms "inside", "outside" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and does not indicate or imply that the device or component must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0061] In the description of the present invention, the description with reference to the terms "one embodiment", "some embodiments", "in the present embodiment", "specific example", or "some examples" etc. means that the specific features, mechanisms, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, mechanisms, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0062] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method for green separation of waste photovoltaic modules, characterized in that: The following steps are involved: S1: pre-treating waste photovoltaic modules to obtain waste photovoltaic module laminates; S2: cutting the waste photovoltaic module laminate to obtain a photovoltaic module laminate sample, wherein the photovoltaic module laminate sample consists of an EVA film, a battery cell, a glass layer and a back sheet; S3: Soaking the photovoltaic module laminate sample in vegetable oil, wherein the mass ratio of the vegetable oil to the photovoltaic module laminate sample is (2-5):1, and the vegetable oil softens the EVA film of the sample through dissolution and penetration, thereby reducing the adhesion between the film and the cell sheet and the glass layer; S4: adding a reaction enzyme to the vegetable oil to obtain a reaction system of the reaction enzyme and the vegetable oil, wherein the reaction enzyme includes one or more of lipase, cellulase, and protease, and the softening of the EVA film is further accelerated by the catalytic action of the reaction enzyme, and the separation of the EVA film from other materials is promoted after soaking; S5: Separating the photovoltaic module laminate sample processed in step S4 to complete the separation of waste photovoltaic modules.

2. The method for green separation of waste photovoltaic modules according to claim 1, characterized in that: In the step S1, the pretreatment includes: removing the aluminum frame and junction box of the waste photovoltaic modules.

3. The method for green separation of waste photovoltaic modules according to claim 1, characterized in that: In step S3, the soaking temperature is 40-60° C., and the soaking time is 1-3 hours.

4. The method for green separation of waste photovoltaic modules according to claim 1, characterized in that: In the step S4, the mass concentration of the reaction enzyme in the reaction system is 1-5%.

5. The method for green separation of waste photovoltaic modules according to claim 1, characterized in that: In the step S4, the reaction enzyme is lipase.

6. The method for green separation of waste photovoltaic modules according to claim 1, characterized in that: In step S4, the soaking temperature is 40-60° C., and the reaction time is 2 to 10 hours.

7. The method for green separation of waste photovoltaic modules according to claim 1, characterized in that: In the step S4, the pH of the reaction system is 5-7, and during the reaction of the step S4, the pH of the reaction system is adjusted by using a phosphate or citric acid buffer.

8. The method for green separation of waste photovoltaic modules according to claim 1, characterized in that: In step S5, the operation of separating the photovoltaic module laminate sample processed in step S4 includes: separating the EVA film, the battery cell, the glass layer and the backplane by mechanical means, and washing the separated battery cell and glass with ethanol to remove residual vegetable oil, reaction enzyme and film.

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