Full component recycling process for decommissioned photovoltaic modules

Abstract

The present application relates to a kind of full-component recycling process of decommissioned photovoltaic module, belong to decommissioned photovoltaic module processing recycling field.The application comprises: S1, decompose decommissioned photovoltaic module, obtain mixed solid;S2, the mixed solid is torn and is carried out primary screening;S3, the product on primary screen is pyrolyzed, and the pyrolysis solid is recycled and is broken and is carried out secondary screening, and pyrolysis gas is carried out deacidification treatment;S4, mixed secondary screening product and primary screening product, and carry out tertiary screening;S5, after the tertiary screening product is mixed with acid liquor, by ultrasonic stirring, primary solid-liquid separation obtains primary solid and primary liquid, and the primary solid is dried, and the drying solid is carried out electrostatic separation;S6, in primary liquid, add soluble chlorides, and then carry out secondary solid-liquid separation;S7, tertiary screening product is recycled and is ground and is carried out quaternary screening, and tertiary screening product is mixed with condensed water, and is carried out flotation.The present application improves energy utilization efficiency, and energy saving, economy and environmental protection are considered.

Description

Technical Field

[0001] This invention relates to the field of processing and recycling retired photovoltaic modules, and particularly to a process for recycling all components of retired photovoltaic modules. Background Technology

[0002] In the process of promoting the green and low-carbon transformation of the energy structure and implementing the national "dual-carbon" goals, solar photovoltaic (PV) has become an important component of my country's energy system due to its cleanliness and renewability. With the continuous expansion of the PV industry, my country's installed PV power generation capacity has firmly established itself among the world's leading positions. However, as early PV projects gradually age, the number of retired PV modules is expected to reach millions within the next decade, exhibiting explosive growth. These retired modules contain a large amount of recyclable resources, such as panel glass, metal frames, semiconductor silicon, and conductive metals. Efficient and environmentally friendly recycling of these valuable resources not only helps reduce environmental pollution risks but also reintegrates these "urban mines" into the industrial chain, alleviating the demand for and pressure on primary resources.

[0003] Current technologies for processing retired photovoltaic modules generally face severe challenges such as low processing efficiency, low resource recycling rates, and potential environmental pollution. Traditional physical methods rely on applying mechanical force to break the adhesiveness of the EVA film, thereby separating the layers. However, this method has low separation efficiency, and the mechanical action is often insufficient, resulting in significant EVA film residue still adhering to the surface of the separated modules, requiring further processing and increasing the overall complexity and cost. Chemical methods use chemical solvents or reagents to dissolve the EVA film to recover relatively intact solar cells, glass, and other components. This method often requires large amounts of corrosive or toxic chemicals, resulting in high processing costs. Furthermore, the use of chemical reagents significantly increases the risk of environmental pollution. Traditional pyrolysis methods soften and decompose the EVA film through high-temperature heating, thereby separating the modules. This process consumes enormous amounts of energy, requires extremely strict emission temperature control, and easily releases toxic gases, seriously threatening environmental safety.

[0004] Existing technical solutions: A method for recovering glass and silicon powder from waste photovoltaic modules is disclosed in patent application number CN202511336760.4. The method includes: crushing the waste photovoltaic modules and mixing the resulting powder with water to form a slurry; adjusting the pH of the slurry to alkaline to obtain an alkaline slurry; mixing the alkaline slurry with a collector, inhibitor, and foaming agent, followed by flotation separation to obtain coarse silicon powder and a glass foam layer; washing the coarse silicon powder to obtain a silicon powder product; and sequentially defoaming, solid-liquid separation, and washing the glass foam layer to obtain a glass product. This method completely ignores the recovery of high-value components such as metallic silver, resulting in incomplete resource utilization; it lacks pre-screening and targeted enrichment of components, leading to low flotation efficiency and high reagent consumption.

[0005] The invention patent application with application number CN202510882058.1 discloses a high-value recycling process for waste photovoltaic modules based on pyrolysis and wet purification, including: pyrolyzing and decarbonizing waste photovoltaic modules to obtain glass plates, crystalline silicon solar cells, and copper-tin solder strips; obtaining dealuminized crystalline silicon wafers through alkaline leaching, acid washing the dealuminized crystalline silicon wafers to obtain desilvered crystalline silicon wafers and silver leaching solution, and extracting elemental silver from the silver leaching solution; removing impurities from the desilvered crystalline silicon wafers with hydrofluoric acid solution to obtain high-purity crystalline silicon wafers; recovering copper strips through high-temperature melting reduction; and removing hydrogen fluoride from the fluorine-containing pyrolysis gas generated during the pyrolysis process through combustion and heat exchange, followed by two-stage alkaline absorption, and then water washing, with the final flue gas being emitted. The proposed scheme has high pyrolysis energy consumption, large reagent consumption in the wet recovery process, and high environmental risks; it does not achieve component pre-separation, resulting in high pyrolysis energy consumption and low efficiency; it relies on highly corrosive chemicals, which poses high environmental risks and costs; and the precious metal recovery path is limited, with silver recovery rate restricted.

[0006] Therefore, this invention aims to solve the technical challenges existing in the current recycling process of retired photovoltaic modules, providing a comprehensive recycling process that is efficient, low-energy, and environmentally friendly. This process utilizes multiple innovative methods, including multi-stage screening, pyrolysis energy-saving optimization, acid washing-ultrasonic surface activation, electrostatic separation, and flotation, to achieve refined processing throughout the entire process from dismantling to final resource recovery. This significantly improves the resource recovery rate, reduces environmental impact, and provides solid technical support for promoting the sustainable development of the photovoltaic industry. This is not only an urgent task for achieving green and low-carbon development but also a strategic measure to safeguard national resource security and build a circular economy system. Summary of the Invention

[0007] The technical problem to be solved by the present invention is: in order to overcome at least one technical problem existing in the prior art, the present invention provides a process for the full-component recycling of retired photovoltaic modules.

[0008] The technical solution adopted by this invention to solve its technical problem is: This invention provides a process for the complete recycling of components from decommissioned photovoltaic modules, comprising: S1. Disassemble retired photovoltaic modules to obtain a mixed solid including glass, silicon wafers and electrode materials; S2. Shred and screen the mixed solid to obtain the product over the first sieve and the product under the first sieve. S3. Pyrolyze the product on the primary sieve to produce pyrolysis solids and pyrolysis gas. The pyrolysis solids are recycled for crushing and secondary screening until all the pyrolysis solids are converted into products under the secondary sieve. The pyrolysis gas is deacidified to obtain deacidified hot gas. S4. Mix the secondary sieve undersize product and the primary sieve undersize product, and perform tertiary sieve separation to obtain the tertiary sieve oversize product and the tertiary sieve undersize product; S5. After mixing the product on the three-stage sieve with acid, the mixture is stirred by ultrasound and separated into a first-stage solid and a first-stage liquid. The first-stage solid is dried using deacidification hot gas to obtain dried solid and condensate. The dried solid is then electrostatically separated to obtain silicon powder and metallic silver. S6. Add soluble chloride salt to the primary liquid and then perform secondary solid-liquid separation to obtain silver chloride and filtrate; S7. The undersize product of the third-stage screen is recycled for grinding and fourth-stage screening until all the undersize product of the third-stage screen is converted into the undersize product of the fourth-stage screen. The undersize product of the fourth-stage screen is mixed with condensate and subjected to flotation to obtain tailings and silver-containing concentrate.

[0009] Furthermore, the distance between the moving blade and the fixed blade of the shredder used for shredding is 1~2mm.

[0010] Furthermore, the sieve aperture of the first-stage sieve is 3mm, the sieve aperture of the second-stage sieve is 3mm, the sieve aperture of the third-stage sieve is 0.25mm, and the sieve aperture of the fourth-stage sieve is 0.1mm.

[0011] Furthermore, the acid solution is at least one of citric acid, nitric acid, and sulfuric acid.

[0012] Furthermore, the soluble chloride salt is at least one of sodium chloride, potassium chloride, calcium chloride, magnesium chloride, ammonium chloride, aluminum chloride, ferric chloride, ferrous chloride, zinc chloride, and copper chloride.

[0013] Furthermore, the concentration of the acid solution is 2% to 15%.

[0014] Furthermore, in step S3, the pyrolysis solids are recycled for crushing and secondary sieving until all pyrolysis solids are converted into secondary sieve products, including: The pyrolysis solids are crushed and screened in two stages to obtain the product above the secondary sieve and the product below the secondary sieve. The product above the secondary sieve is then returned to be crushed and screened again until all the pyrolysis solids are converted into the product below the secondary sieve.

[0015] Furthermore, in step S7, the undersize product from the third-stage screening is circulated through grinding and fourth-stage screening until all the undersize product from the third-stage screening is converted into undersize product from the fourth-stage screening, including: The undersize product of the third-stage screen is ground and screened in four stages to obtain the oversize product of the fourth-stage screen and the undersize product of the fourth-stage screen. The oversize product of the fourth-stage screen is then returned to be ground and screened in four stages again until all the undersize products of the third-stage screen are converted into undersize products of the fourth-stage screen.

[0016] Furthermore, the pyrolysis temperature is 450℃~600℃, and the time is 30min~120min.

[0017] Furthermore, the shredder used for shredding is at least one of a single-shaft shredder, a dual-shaft shredder, and a four-shaft shredder.

[0018] The beneficial effects of this invention are: 1. Significantly reduces pyrolysis energy consumption and improves energy utilization efficiency: Through shredding and primary sieving (3mm sieve aperture), fine powder materials with a particle size of 3mm or less are effectively separated. The product on the primary sieve is mainly enriched with EVA film, residual glass, and metallic silver, with a significantly reduced glass content. Since glass absorbs a large amount of heat during pyrolysis but does not participate in the pyrolysis reaction, reducing glass significantly reduces ineffective heat consumption, thereby greatly saving energy consumption in the pyrolysis process and improving the overall energy efficiency of the process.

[0019] 2. Efficient removal of silver oxide layer and significant improvement of precious metal recovery rate: Introducing acid solution into the product of the three-stage sieve and combining it with ultrasonic stirring treatment can quickly and effectively etch away the oxide film and organic pollutants on the surface of silver particles in retired photovoltaic modules, making the surface of silver particles clean and restoring conductivity. This significantly improves the separation efficiency and recovery yield of silver and silicon powder in the subsequent electrostatic separation process, and achieves efficient recovery of high-value silver.

[0020] 3. A refined, closed-loop process balancing high purity and economy: This process achieves precise separation of different particle sizes and phases through multi-stage synergistic treatment including four-stage screening, grinding return, flotation, and chloride precipitation. Simultaneously, the high-temperature gas generated by pyrolysis is used to dry solid products, realizing waste heat recovery, while coarse particles on the screen are returned to crushing or grinding, thus forming a closed-loop control. This not only ensures the high purity of products such as silicon powder, silver, and silver chloride, but also reduces raw material loss and operating costs, improving the resource utilization efficiency and economic benefits of the entire recovery system. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0022] Figure 1 This is a flowchart of the process for recycling all components of retired photovoltaic modules according to the present invention; Figure 2 This is a schematic diagram of the full-component recycling process for retired photovoltaic modules according to the present invention. Detailed Implementation

[0023] Before discussing the exemplary embodiments in more detail, it should be noted that some exemplary embodiments are described as processes or methods depicted as flowcharts. Although the flowcharts describe the operations as sequential processes, many of these operations can be performed in parallel, concurrently, or simultaneously. Furthermore, the order of the operations can be rearranged. The process can be terminated when its operation is completed, but may also have additional steps not included in the figures. The process can correspond to a method, function, procedure, subroutine, subroutine, etc.

[0024] It should be understood that although the terms "first," "second," etc., may be used herein to describe various units, these units should not be limited by these terms. These terms are used merely to distinguish one unit from another. For example, without departing from the scope of the exemplary embodiments, a first unit may be referred to as a second unit, and similarly, a second unit may be referred to as a first unit. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0025] The present invention will now be described in detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0026] For ease of understanding, the inventive concept will be described in its entirety before a detailed description of the embodiments of the present invention: This invention addresses the problems of high energy consumption, low recovery rate, and incomplete separation in the recycling of decommissioned photovoltaic modules. It proposes an innovative process that combines multi-stage screening pretreatment, pyrolysis energy saving, acid washing and ultrasonic surface activation, dual-path recovery via electrostatic separation and flotation, and chloride precipitation. The core of this process is to use screening to separate glass in advance to reduce pyrolysis energy consumption, use acid combined with ultrasonic stirring to remove the oxide film on the silver surface to improve sorting efficiency, and combine electrostatic separation to recover coarse silver, flotation to recover fine silver, and chloride precipitation to recover dissolved silver in a closed-loop recovery strategy covering all particle sizes. Ultimately, this achieves efficient separation and recovery of high-value components such as silver, silicon, and glass.

[0027] like Figure 1 and 2 As shown, this invention provides a process for the complete recycling of all components of retired photovoltaic modules, including: S1. Disassemble the retired photovoltaic modules, remove their aluminum frames, junction boxes and back panels, etc., to obtain a mixed solid including glass, silicon wafers and electrode materials.

[0028] S2. Shred and screen the mixed solids to obtain the product above the first sieve and the product below the first sieve.

[0029] The shredder used for shredding has a moving blade and a fixed blade spacing of 1-2 mm. The shredder is at least one of a single-shaft shredder, a double-shaft shredder, or a four-shaft shredder. The screen aperture of the primary screening is 3 mm.

[0030] It should be noted that shredding and primary sieving can effectively separate fine powder materials with a particle size of 3 mm or less. The product on the primary sieve with a particle size greater than 3 mm is mainly enriched with EVA film, residual glass, and metallic silver, with the glass content significantly reduced. Since glass absorbs a large amount of heat during pyrolysis but does not participate in the pyrolysis reaction, reducing the glass content can significantly reduce ineffective heat consumption, thereby greatly saving energy consumption in the pyrolysis process and improving the overall energy efficiency of the process.

[0031] S3. The product over the primary sieve is pyrolyzed at a temperature of 450℃~600℃ for 30min~120min, producing pyrolysis solids and pyrolysis gases. The pyrolysis solids are then recycled for crushing and secondary sieving until all pyrolysis solids are converted into products under the secondary sieve. The pyrolysis gases are then deacidified to remove acidic gases such as hydrogen fluoride produced during pyrolysis, yielding deacidified hot gas. The sieve aperture for the secondary sieve is 3mm.

[0032] Specifically, the pyrolysis solids are crushed and subjected to secondary sieving to obtain products above and below the secondary sieve. The products above the secondary sieve are then returned for further crushing and secondary sieving until all the pyrolysis solids are converted into products below the secondary sieve.

[0033] S4. Mix the products under the secondary sieve and the products under the primary sieve, and then perform tertiary sieve separation to obtain the products over the tertiary sieve and the products under the tertiary sieve. The sieve aperture of the tertiary sieve is 0.25 mm.

[0034] S5. After mixing the product from the three-stage sieve with acid, ultrasonic stirring and primary solid-liquid separation are performed to obtain primary solid and primary liquid. This can quickly and effectively etch away the oxide film and organic pollutants on the surface of silver particles in decommissioned photovoltaic modules, making the surface of silver particles clean and restoring conductivity. This significantly improves the separation efficiency and recovery yield of silver and silicon powder in the subsequent electrostatic separation process, achieving efficient recovery of high-value silver.

[0035] Then, the primary solid is dried using the deacidification heat gas to obtain dried solid and condensate. The dried solid is then electrostatically separated to obtain silicon powder and metallic silver. The high-temperature gas generated by pyrolysis is used to dry the primary solid, realizing waste heat recovery. The acid solution is at least one of citric acid, nitric acid, and sulfuric acid, and the concentration of the acid solution is 2% to 15%.

[0036] S6. Add soluble chloride salt to the primary liquid, followed by secondary solid-liquid separation to obtain silver chloride and filtrate. Converting dissolved silver into solid silver chloride precipitate for recovery ensures the integrity of silver recovery and significantly reduces the heavy metal silver content in the waste liquid.

[0037] The soluble chloride salt is at least one of sodium chloride, potassium chloride, calcium chloride, magnesium chloride, ammonium chloride, aluminum chloride, ferric chloride, ferrous chloride, zinc chloride, and copper chloride.

[0038] S7. The product undersize from the third-stage screening is recycled through grinding and fourth-stage screening until all the product undersize from the third-stage screening is converted into product undersize from the fourth-stage screening. The product undersize from the fourth-stage screening is mixed with condensate and subjected to flotation to obtain tailings and silver-containing concentrate. The sieve aperture of the fourth-stage screening is 0.1 mm.

[0039] Specifically, the undersize product of the third-stage screen is ground and screened in four stages to obtain the oversize product of the fourth-stage screen and the undersize product of the fourth-stage screen. The oversize product of the fourth-stage screen is then returned to be ground and screened in four stages again until all the undersize products of the third-stage screen are converted into undersize products of the fourth-stage screen.

[0040] Example 1 Take a retired crystalline silicon photovoltaic module (approximately 280 W power), first remove its aluminum frame, junction box, and backsheet, obtaining a mixed solid mainly composed of glass, EVA film, silicon wafer, and silver electrodes. Feed this mixed solid into a shredder for shredding, controlling the distance between the moving and stationary blades to 1.5 mm, to obtain a powder product with a relatively wide particle size distribution.

[0041] The powdered product is fed into a vibrating screen for primary sieving (3mm aperture) to obtain primary sieve oversize product (>3mm) and primary sieve undersize product (≤3mm). The primary sieve oversize product is placed in a tubular pyrolysis furnace to pyrolyze EVA at 500℃ for 40 minutes, yielding pyrolysis solids and high-temperature pyrolysis gas. The pyrolysis gas is then treated with an alkaline agent to remove acidic gases such as HF before being used in subsequent drying processes.

[0042] The pyrolysis solids are crushed by a hammer crusher and then subjected to secondary screening (3mm sieve aperture) to obtain secondary oversize product (returned to crushing and secondary screening) and secondary undersize product (≤3mm). The primary undersize product is mixed with the secondary undersize product and subjected to tertiary screening (0.25mm sieve aperture) to obtain tertiary oversize product (>0.25mm) and tertiary undersize product (≤0.25mm).

[0043] The product from the three-stage sieve was mixed with a "5% sulfuric acid + 2% citric acid mixed solution" at a solid-liquid ratio of 1:4, and then added to an ultrasonically stirred tank. The mixture was ultrasonically stirred for 40 minutes at a frequency of 40 kHz and a power of 300 W. Subsequently, the mixture was separated into a primary solid and a primary liquid by a vacuum filter.

[0044] The primary solid is dried using the high-temperature gas (approximately 150-250 °C) generated by the aforementioned pyrolysis, yielding dried solid and condensate (i.e., drying water). The dried solid is then fed into a high-voltage electrostatic separator (30 kV) to separate high-purity silicon powder and metallic silver particles with a purity of 98.5%.

[0045] Sodium chloride was added to the primary liquid, and the mixture was stirred and reacted for 30 minutes. The mixture was then filtered using a plate and frame filter press to obtain the secondary solid product, silver chloride, and the filtrate.

[0046] The product under the third-stage sieve (≤0.25mm) is fed into a ball mill for grinding. After grinding, it is subjected to a fourth-stage sieve (sieve aperture 0.1mm). The product over the fourth-stage sieve is returned to the grinding mill. The product under the fourth-stage sieve (≤0.1mm) is mixed with the aforementioned condensate, and an appropriate amount of butyl ammonium black reagent collector and MIBC frother are added. The mixture is then floated in a flotation cell to obtain a concentrate rich in fine silver and fine silica tailings.

[0047] According to calculations, in this embodiment, the total silver recovery rate is 93.6%, the silicon powder recovery rate is 95.3%, the pyrolysis energy consumption is reduced by about 38% compared with the traditional whole plate pyrolysis, and there is no emission of toxic gases throughout the process.

[0048] Example 2 The difference from Example 1 is that: a 10% nitric acid solution was used as the acid solution, and the ultrasonic stirring time was 30 min; potassium chloride was used as the chloride salt; and a two-stage flotation process was adopted to improve the silver enrichment ratio. All other conditions were the same.

[0049] The results showed that the total silver recovery rate was 94.5%, silver chloride precipitation was complete, and the silicon powder recovery rate was 95.8%, with the overall resource utilization efficiency still better than that of conventional processes.

[0050] Example 3 The difference from Example 1 is that the distance between the shredder motor blade and the fixed blade is adjusted to 1.0 mm, the primary sieve aperture is still 3 mm, ensuring that the glass content in the primary sieve is less than 15%; the pyrolysis temperature is reduced to 480 ℃, and the time is maintained at 40 min; the acid solution is 8% citric acid.

[0051] Compared to Example 1, this scheme further reduces pyrolysis energy consumption by 12%, balances oxide film removal and environmental friendliness with the use of acid, but is weaker, and achieves a silver recovery rate of 92.8%, verifying the adjustability of process parameters.

[0052] Comparative Example 1 The difference from Example 1 is that the first-stage sieving step is omitted, and all the shredded powder is directly pyrolyzed (i.e., no fine powder ≤3mm is separated). The remaining steps are the same.

[0053] Because a large amount of fine glass powder (≤3 mm) entered the pyrolysis furnace, the heat absorption increased significantly, and the pyrolysis energy consumption increased by about 45%. Moreover, the fine powder was prone to sintering and agglomeration during pyrolysis, making subsequent crushing difficult and causing severe silver particle encapsulation. Ultimately, the silver recovery rate was only 68.3%, and the silicon powder purity also decreased to 92%.

[0054] Comparative Example 2 The difference from Example 1 is that the acid washing and ultrasonic steps are omitted, and the product on the three-stage sieve is directly dried and then electrostatically separated.

[0055] Because the silver particles are still covered with EVA carbonization residue and oxide film, their conductivity is poor, resulting in a significant reduction in electrostatic separation efficiency and a large amount of silver being mixed into the silicon powder product. Testing showed that the silver recovery rate was only 57.9%, and the silicon powder product contained excessive amounts of silver, affecting its reuse value as an industrial silicon raw material.

[0056] Comparative Example 3 The difference from Example 1 is that the step of "adding soluble chloride salt to the primary liquid" is omitted, meaning that the dissolved silver in the pickling solution is not precipitated and recovered; solid silver is recovered solely through electrostatic separation and flotation. All other process conditions remain the same.

[0057] The results showed that although the solid silver recovery was good, some silver was lost as Ag during the acid washing process. + The silver entered the solution in ionic form and was not recovered, causing the total silver recovery rate of the system to drop to 85.4%. ICP analysis revealed a residual silver concentration of 6.7 mg / L in the filtrate, resulting not only in resource waste but also increased burden on wastewater treatment. This comparative example illustrates that the chloride precipitation step is crucial for achieving closed-loop recovery of silver in all its forms.

[0058] Comparative Example 4 The difference from Example 1 is that the step of "mixing the product undersize from the fourth sieve with condensate and then performing flotation" is omitted. That is, ultrafine particles ≤0.1 mm are not subjected to flotation treatment, and silver is recovered solely by electrostatic separation. The remaining steps are the same.

[0059] Because the ≤0.1mm particle size contains fine silver particles resulting from broken or ground-off silver grid lines, these particles have poor conductivity and are lightweight, making them difficult to capture effectively through electrostatic separation. Testing revealed that the silver content in this portion of the tailings was still as high as 28%, reducing the overall silver recovery rate to 82.1%. This comparative example verifies that the dual-path recovery method of "coarse-grained electrostatic separation + fine-grained flotation" plays an irreplaceable role in improving the overall silver recovery rate.

[0060] The above descriptions are merely embodiments of the present invention. Common knowledge such as specific structures and characteristics known in the solutions are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the technical field to which the invention pertains before the application date or priority date, are able to obtain all prior art in the field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can improve and implement the solution based on the inspiration given in this application and their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application.

Claims

1. A process for the complete recycling of components from decommissioned photovoltaic modules, characterized in that, include: S1. Disassemble retired photovoltaic modules to obtain a mixed solid including glass, silicon wafers and electrode materials; S2. Shred and screen the mixed solid to obtain the product over the first sieve and the product under the first sieve. S3. Pyrolyze the product on the primary sieve to produce pyrolysis solids and pyrolysis gas. The pyrolysis solids are recycled for crushing and secondary screening until all the pyrolysis solids are converted into products under the secondary sieve. The pyrolysis gas is deacidified to obtain deacidified hot gas. S4. Mix the secondary sieve undersize product and the primary sieve undersize product, and perform tertiary sieve separation to obtain the tertiary sieve oversize product and the tertiary sieve undersize product; S5. After mixing the product on the three-stage sieve with acid, the mixture is stirred by ultrasound and separated into a first-stage solid and a first-stage liquid. The first-stage solid is dried using deacidification hot gas to obtain dried solid and condensate. The dried solid is then electrostatically separated to obtain silicon powder and metallic silver. S6. Add soluble chloride salt to the primary liquid and then perform secondary solid-liquid separation to obtain silver chloride and filtrate; S7. The undersize product of the third-stage screen is recycled for grinding and fourth-stage screening until all the undersize product of the third-stage screen is converted into the undersize product of the fourth-stage screen. The undersize product of the fourth-stage screen is mixed with condensate and subjected to flotation to obtain tailings and silver-containing concentrate.

2. The process for full-component recycling of decommissioned photovoltaic modules according to claim 1, characterized in that, The distance between the moving blade and the fixed blade of the shredder used for shredding is 1~2mm.

3. The process for recycling all components of decommissioned photovoltaic modules according to claim 1, characterized in that, The sieve aperture of the first-stage sieve is 3mm, the sieve aperture of the second-stage sieve is 3mm, the sieve aperture of the third-stage sieve is 0.25mm, and the sieve aperture of the fourth-stage sieve is 0.1mm.

4. The process for recycling all components of decommissioned photovoltaic modules according to claim 1, characterized in that, The acid solution is at least one of citric acid, nitric acid, and sulfuric acid.

5. The process for full-component recycling of decommissioned photovoltaic modules according to claim 1, characterized in that, The soluble chloride salt is at least one of sodium chloride, potassium chloride, calcium chloride, magnesium chloride, ammonium chloride, aluminum chloride, ferric chloride, ferrous chloride, zinc chloride, and copper chloride.

6. The process for full-component recycling of decommissioned photovoltaic modules according to claim 1, characterized in that, The concentration of the acid solution is 2% to 15%.

7. The process for full-component recycling of decommissioned photovoltaic modules according to claim 1, characterized in that, In step S3, the pyrolysis solids are recycled for crushing and secondary sieving until all pyrolysis solids are converted into secondary sieve products, including: The pyrolysis solids are crushed and screened in two stages to obtain the product above the secondary sieve and the product below the secondary sieve. The product above the secondary sieve is then returned to be crushed and screened again until all the pyrolysis solids are converted into the product below the secondary sieve.

8. The process for recycling all components of decommissioned photovoltaic modules according to claim 1, characterized in that, In step S7, the undersize product from the third-stage screening is circulated through grinding and quaternary screening until all the undersize product from the third-stage screening is converted into undersize product from the fourth-stage screening, including: The undersize product of the third-stage screen is ground and screened in four stages to obtain the oversize product of the fourth-stage screen and the undersize product of the fourth-stage screen. The oversize product of the fourth-stage screen is then returned to be ground and screened in four stages again until all the undersize products of the third-stage screen are converted into undersize products of the fourth-stage screen.

9. The process for full-component recycling of decommissioned photovoltaic modules according to claim 1, characterized in that, The pyrolysis temperature is 450℃~600℃, and the time is 30min~120min.

10. The process for recycling all components of decommissioned photovoltaic modules according to claim 1, characterized in that, The shredder used for shredding is at least one of a single-shaft shredder, a dual-shaft shredder, or a four-shaft shredder.

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