Method for synergistically recovering all elements of crystal silicon battery piece of retired photovoltaic module

Abstract

The invention provides a method for synergistically recovering all elements of crystal silicon cells of a decommissioned photovoltaic module, which comprises the following steps of: collecting large-particle waste crystal silicon cells and grinding the large-particle waste crystal silicon cells to obtain powder; the powder is leached with nitric acid, and leach liquor and impurity-removed silicon powder are obtained; leaching the silicon powder subjected to impurity removal by using an HF solution to remove a silicon nitride layer, and filtering, washing and drying to obtain the silicon powder meeting the industrial standard; the leaching solution is subjected to chlorination precipitation to obtain silver chloride and a leaching solution with silver removed, and after the silver chloride is filtered, the silver chloride is subjected to acid pickling and water washing to obtain silver chloride; sodium sulfide is added into the leaching solution after silver removal, metal in the leaching solution is precipitated, and a solution containing Al < 3 + > can be obtained after filtering; the method comprises the following steps: adding an alkaline substance into a solution containing Al < 3 + >, filtering to obtain an aluminum hydroxide precipitate, and washing the aluminum hydroxide precipitate to remove foreign ions adsorbed on the surface; one technical effect of the invention is that collaborative recovery and treatment of each element in the waste crystal silicon battery piece are realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of resource utilization of waste photovoltaic modules, and particularly relates to a method for co-recovering all elements of crystalline silicon solar cells in retired photovoltaic modules. Background Art

[0002] Generally, the service life of photovoltaic modules is 20 - 25 years. With the replacement and expiration of the service life of photovoltaic modules, the problem of a sharp increase in the scrapped amount of photovoltaic modules is becoming increasingly serious, and its recycling problem cannot be underestimated. The photovoltaic cell market is dominated by crystalline silicon cells, with a market share of more than 90%. Therefore, the recycling and disposal market for waste crystalline silicon photovoltaic modules has great prospects.

[0003] The aluminum frame and junction box in waste crystalline silicon photovoltaic modules can be recycled by mechanical disassembly. The organic binder (EVA) can be delaminated from the laminate by methods such as physical crushing separation, high-temperature thermal decomposition, and chemical dissolution. Glass, welding rods, and waste crystalline silicon solar cells can be separated and enriched by methods such as screening and color sorting. The glass and welding rods separated from the laminate can be directly sold and utilized, but the solar cells still need to be further recycled by wet chemical methods. The middle of the waste crystalline silicon solar cell is a silicon matrix, and the surface contains silver grid lines, aluminum electrodes, a passivation layer, Si 3 N 4 anti-reflection coating, etc. It has a complex structure and numerous components. Since it contains Al, Al 2 O 3 , Si, Si 3 N 4 , Ag, Cu, Pb, Fe and other substances, this is the reason for its difficult resource recycling.

[0004] Currently, for the resource recycling of waste crystalline silicon photovoltaic cells, most attention is paid to the recycling of silver and silicon with high value, and there are problems such as complex recycling steps and low product purity. In the aspect of silicon element recycling, the purification of silicon is usually achieved by the method of removing aluminum - removing silver - removing silicon nitride. In the aspect of aluminum removal and aluminum resource application, according to the amphoteric characteristics of aluminum, there are usually two paths. One is to leach aluminum with alkaline (NaOH and KOH) solutions, and the other is to leach aluminum with acidic (HCl, H 2 SO 4 and HNO 3 ) solutions, and then neutralize and precipitate to form Al(OH) 3 , thus realizing the recycling of aluminum resources. However, in the process of aluminum removal by the alkali method, a side reaction of silicon dissolution will occur, which will cause a large amount of silicon impurities in the aluminum hydroxide product directly obtained by acid neutralization, making it difficult for aluminum hydroxide to meet the chemical grade standard; while in the process of aluminum removal by the acid method, co-dissolution of co-existing metals (Fe, Cu, Pb, etc.) in the solar cells is likely to occur, and direct alkali neutralization will cause a co-precipitation reaction, resulting in the prepared Al(OH) 3contains other metal precipitates, resulting in low purity. There are few reports on the high-purity recovery of aluminum resources in silicon wafers. After removing aluminum, silver is further removed, usually using nitric acid solution, followed by adding OH - 、Cl - 、S 2- etc. to precipitate silver ions, and there is also the problem of low purity of silver products. In addition, since there will inevitably be other inclusions, such as solder tapes, iron filings, etc. after the silicon wafers are sorted, these substances will inevitably affect the high-purity recycling of silicon wafers. At the same time, silicon solar cells contain heavy metals such as lead and copper, which will cause harm to the environment if not treated.

[0005] Therefore, there is an urgent need for a method for the collaborative recovery and treatment of all elements of crystalline silicon solar cells in retired photovoltaic modules to solve the above technical problems. Summary of the Invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art, and provides a new technical solution for a method for the collaborative recovery of all elements of crystalline silicon solar cells in retired photovoltaic modules.

[0007] According to a first aspect of the present invention, there is provided a method for the collaborative recovery of all elements of crystalline silicon solar cells in retired photovoltaic modules, including the following steps:

[0008] Step S1, collecting large-particle waste crystalline silicon solar cells and grinding them to obtain powder;

[0009] Step S2, leaching the powder with nitric acid, and after filtration, obtaining a leaching solution and silicon powder after impurity removal; wherein, the leaching solution contains silver, aluminum, copper, lead and iron;

[0010] Step S3, leaching the silicon powder after impurity removal with an HF solution to remove the silicon nitride layer, and after filtration, washing and drying, obtaining silicon powder meeting industrial standards;

[0011] Step S4, obtaining silver chloride and the leaching solution after silver removal by chloride precipitation of the leaching solution, filtering the silver chloride, and then obtaining secondary industrial silver chloride meeting the standards after pickling-rinsing with water;

[0012] Step S5, adding sodium sulfide to the leaching solution after silver removal to precipitate the metals therein, and after filtration, a solution containing Al 3+ can be obtained; wherein, the metals include copper, lead and iron;

[0013] Step S6, adding an alkaline substance to the solution containing Al 3+ to neutralize and precipitate to form aluminum hydroxide, filtering to obtain an aluminum hydroxide precipitate, and then slurry-washing the aluminum hydroxide precipitate to remove the impurity ions adsorbed on the surface, and drying to obtain an aluminum hydroxide product.

[0014] Optionally, in step S1, the maximum size of the powder material is less than 200 μm.

[0015] Optionally, in step S2, the nitric acid leaching conditions are as follows: the leaching concentration of nitric acid is 3 mol / L - 8 mol / L, the leaching time is 1 h - 3 h, the leaching temperature is 40°C - 90°C, the leaching liquid-solid ratio is 5:1 - 20:1, and the stirring speed is 50 r / min - 500 r / min.

[0016] Optionally, in step S2, ultrasonic waves are used during the leaching process to promote the leaching of soluble metals; among them, the ultrasonic power is 20 W - 100 W.

[0017] Optionally, in step S3, the HF solution leaching conditions are as follows: the concentration of the HF solution is 5% - 30%, the reaction time is 5 min - 30 min, the reaction temperature is room temperature, the leaching liquid-solid ratio is 5:1 - 20:1, and the stirring speed is 50 r / min - 500 r / min.

[0018] Optionally, in step S4, during the chloride precipitation process, the chlorides used include at least one of sodium chloride, potassium chloride, and concentrated hydrochloric acid.

[0019] Optionally, in step S4, the obtained silver chloride is first washed with dilute nitric acid, and the pH of the dilute nitric acid is 0.8 - 2.5; then, it is washed with pure water, and the liquid-solid ratio during the washing process is 5:1 - 10:1, and the washing temperature is 20°C - 80°C.

[0020] Optionally, in step S5, first use NaOH to adjust the pH of the leaching solution after silver removal to 1 - 2.5; then, add sodium sulfide, and the addition amount of sodium sulfide is 0.5 g / L - 5 g / L, and the precipitation time is 5 min - 20 min.

[0021] Optionally, in step S6, the alkaline substance includes at least one of sodium hydroxide, potassium hydroxide, ammonia water, sodium carbonate, potassium carbonate, and sodium bicarbonate.

[0022] Optionally, in step S6, the liquid-solid ratio of the aluminum hydroxide precipitate slurry washing is 5:1 - 10:1, the washing temperature is 20°C - 80°C, and the number of slurry washing times is at least 3 times.

[0023] One technical effect of the present invention is that:

[0024] In the embodiment of the present application, the method for co-recovering all elements of crystalline silicon solar cells in retired photovoltaic modules aims at the resource utilization of elements in crystalline silicon solar cells of retired photovoltaic modules. It adopts a fully wet process, mainly including steps such as nitric acid leaching - silver chloride precipitation - sulfide precipitation - aluminum hydroxide precipitation, etc. Silicon purification can be achieved through two-step acid treatment. In terms of aluminum resource utilization, other metal ions are removed by sulfide precipitation, which not only ensures the purity of silver chloride and aluminum hydroxide products, both of which can meet industrial standards, but also realizes the enrichment and solidification of heavy metals in the solution, and realizes the co-recovery and treatment of various elements in waste crystalline silicon solar cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 FIG. is a schematic flow chart of a method for co-recovering all elements of crystalline silicon solar cells in a retired photovoltaic module according to an embodiment of the present invention;

[0026] Figure 2 FIG. is a schematic flow chart of a method for co-recovering all elements of crystalline silicon solar cells in a retired photovoltaic module according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] Now, various exemplary embodiments of the present application will be described in detail with reference to the accompanying drawings. It should be noted that: Unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and values set forth in these embodiments do not limit the scope of the present application.

[0028] The embodiments of the present application will be described in detail below. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary only for explaining the present application and should not be construed as limiting the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the scope of protection of the present application.

[0029] According to the first aspect of the present invention, referring to Figure 1 and Figure 2 , a method for co-recovering all elements of crystalline silicon solar cells in a retired photovoltaic module is provided to specifically solve problems such as complex process flow, low purity of aluminum and silver products, and environmental pollution of other heavy metals in the existing recovery of waste photovoltaic silicon solar cells.

[0030] Specifically, the method for co-recovering all elements of crystalline silicon solar cells in a retired photovoltaic module

[0031] includes the following steps:

[0032] Step S1, collecting large-particle waste crystalline silicon solar cells and grinding them to obtain powder;

[0033] Step S2: Leach the powder with nitric acid. After filtration, a leachate and silicon powder after impurity removal are obtained. Among them, the leachate contains silver, aluminum, copper, lead, and iron. Nitric acid is used to leach soluble metals in the powder.

[0034] Step S3: Leach the silicon powder after impurity removal with an HF solution to remove the silicon nitride layer. After filtration, washing, and drying, silicon powder meeting industrial standards is obtained.

[0035] Step S4: Obtain silver chloride and the leachate after silver removal by chlorination precipitation of the leachate. After filtering the silver chloride, secondary industrial silver chloride meeting the standards is obtained after pickling - water washing.

[0036] Step S5: Add sodium sulfide to the leachate after silver removal to precipitate the metals therein and obtain a heavy metal sulfide enrichment slag. After filtration, a solution containing Al 3+ can be obtained, thereby removing heavy metal ions in the leachate after silver removal. Among them, the metals include copper, lead, and iron.

[0037] Step S6: Add an alkaline substance to the solution containing Al 3+ to neutralize and precipitate aluminum hydroxide. After filtration, an aluminum hydroxide precipitate is obtained. Then, the aluminum hydroxide precipitate is slurried and washed to remove adsorbed impurity ions on the surface, and an aluminum hydroxide product is obtained after drying.

[0038] In the embodiment of the present application, the method for co - recycling all elements of crystalline silicon solar cell wafers from retired photovoltaic modules aims at the resource utilization of elements in crystalline silicon solar cell wafers of retired photovoltaic modules. A fully wet process is adopted, mainly including steps such as nitric acid leaching - silver chloride precipitation - sulfide precipitation - aluminum hydroxide precipitation. Silicon purification can be achieved through two - step acid treatment. In terms of aluminum resource utilization, other metal ions are removed by sulfide precipitation, which not only ensures the purity of silver chloride and aluminum hydroxide products to meet industrial standards, but also realizes the enrichment and solidification of heavy metals in the solution, achieving the co - recycling and treatment of various elements in waste crystalline silicon solar cell wafers.

[0039] Optionally, in step S1, the maximum size of the powder is less than 200 μm. This helps with subsequent processing of the powder. For example, it significantly improves the efficiency of nitric acid leaching.

[0040] Optionally, in step S2, the conditions for nitric acid leaching are as follows: the leaching concentration of nitric acid is 3 mol / L - 8 mol / L, the leaching time is 1 h - 3 h, the leaching temperature is 40°C - 90°C, the leachate - to - solid ratio is 5:1 - 20:1, and the stirring speed is 50 r / min - 500 r / min.

[0041] In the above - mentioned embodiment, the efficiency of nitric acid solution leaching is preferably ensured, which helps to obtain silicon powder after impurity removal.

[0042] Optionally, in step S2, ultrasonic waves are applied during the leaching process to promote the leaching of soluble metals; among them, the ultrasonic power is 20W - 100W. This can further improve the leaching effect of the nitric acid solution.

[0043] Optionally, in step S3, the leaching conditions of the HF solution are as follows: the concentration of the HF solution is 5% - 30%, the reaction time is 5min - 30min, the reaction temperature is room temperature, the leaching liquid-solid ratio is 5:1 - 20:1, and the stirring speed is 50r / min - 500r / min.

[0044] In the above embodiment, the leaching conditions of the HF solution are relatively reasonable and can better remove the silicon nitride layer.

[0045] Exemplarily, in step S3, the silicon wafer after removing the silicon nitride layer is washed three times with pure water, the liquid-solid ratio during the washing process is 5:1, and the water temperature is room temperature.

[0046] Optionally, in step S4, during the chloride precipitation process, the chlorides used include at least one of sodium chloride, potassium chloride, and concentrated hydrochloric acid. This can better ensure the effect of chloride precipitation.

[0047] Exemplarily, the added molar amount of the chloride is n(Cl - ): n(Ag + ) = 1:5, the chloride precipitation time is 10min - 60min, and the precipitation temperature is room temperature.

[0048] Optionally, in step S4, the obtained silver chloride is first washed with dilute nitric acid, and the pH of the dilute nitric acid is 0.8 - 2.5; then, it is washed with pure water again, the liquid-solid ratio during the washing process is 5:1 - 10:1, and the washing temperature is 20°C - 80°C. This helps to obtain secondary industrial silver chloride that meets the standards.

[0049] Optionally, in step S5, first use NaOH to adjust the pH of the leaching solution after silver removal to 1 - 2.5; then, add sodium sulfide, and the added amount of sodium sulfide is 0.5g / L - 5g / L, and the precipitation time is 5min - 20min.

[0050] In the above embodiment, the metals in the leaching solution after silver removal can be precipitated to obtain heavy metal sulfide enrichment slag.

[0051] Optionally, in step S6, the alkaline substance includes at least one of sodium hydroxide, potassium hydroxide, ammonia water, sodium carbonate, potassium carbonate, and sodium bicarbonate, that is, the alkaline substance includes hydroxides and carbonates. This can effectively neutralize the solution containing Al 3+ and form aluminum hydroxide precipitate.

[0052] Optionally, in step S6, the liquid-solid ratio of the washing of the aluminum hydroxide precipitate is 5:1 - 10:1, the washing temperature is 20°C - 80°C, and the number of washing times is at least 3 times. This can better ensure the purity of the obtained aluminum hydroxide product.

[0053] Exemplarily, in step S6, the end point pH of the solution neutralization is 7 - 9, and the aging time is 1 h - 3 h.

[0054] Example 1

[0055] First, grind large-sized waste crystalline silicon solar cells to less than 200 μm, leach the cell powder sample with 8 mol / L nitric acid, the leaching temperature is 60°C, the liquid-solid mass ratio of the leaching is 10:1, the leaching time is 2 h, the stirring speed is 400 r / min, the ultrasonic power during the leaching process is 100 W, and filter to obtain a leaching solution containing silver, aluminum, copper and other ions.

[0056] Next, further treat the above silicon powder sample with 20% HF solution, the reaction time is 10 min, the reaction temperature is room temperature, the liquid-solid ratio of the leaching is 10:1, the stirring speed is 300 r / min, then wash the powder sample three times with pure water, the liquid-solid ratio during the washing process is 5:1, the water temperature is room temperature, and the purity of silicon in the dried silicon powder is 99.4%, meeting the requirements of industrial silicon powder.

[0057] Then, add concentrated hydrochloric acid to the leaching solution, the added molar amount n(Cl - ):n(Ag + ) is 5, after reacting for 10 min, filter to obtain silver chloride precipitate, the precipitation rate of silver in the leaching solution is 99.6%, first wash the obtained silver chloride precipitate with nitric acid solution with a pH of 0.8, and then wash it with pure water, the liquid-solid ratio during the washing process is 5:1, the washing temperature is 60°C, and the purity of the obtained silver chloride after drying is 99.3%.

[0058] Then, adjust the pH of the leaching solution after removing silver to about 2, add sodium sulfide, the added amount is 5 g / L, the precipitation time is 20 min, to obtain metal sulfide precipitate, and this metal sulfide precipitate can be further used for metal extraction as enriched slag.

[0059] Finally, add sodium hydroxide to neutralize the Al 3+ -containing solution after impurity removal, the end point pH of the neutralization is 9, the aging time is 2 h, to obtain aluminum hydroxide precipitate. Further wash the aluminum hydroxide precipitate with pure water to remove adsorbed impurity ions, the liquid-solid ratio of the washing solution is 10:1, the washing temperature is 80°C, the number of washing times is 3 times, and the purity of the obtained aluminum hydroxide after drying is 99.2%.

[0060] Example 2

[0061] First, grind large-sized waste crystalline silicon solar cells to less than 200 μm, leach the powdered cell samples with 3 mol / L nitric acid at a leaching temperature of 40 °C, a leaching liquid-solid mass ratio of 5:1, a leaching time of 3 h, a stirring speed of 400 r / min, an ultrasonic power of 20 W during the leaching process, and filter to obtain a leaching solution containing silver, aluminum, copper and other ions.

[0062] Next, further treat the above-mentioned silicon powder samples with 30% HF solution for 5 min at room temperature, with a leaching liquid-solid ratio of 5:1 and a stirring speed of 300 r / min. Then wash the powder samples three times with pure water, with a liquid-solid ratio of 5:1 during the washing process and room temperature water. After drying, the purity of silicon in the silicon powder is 96.3%, which is difficult to meet the requirements of industrial silicon powder.

[0063] Then, add concentrated hydrochloric acid to the leaching solution, with the molar amount n(Cl - ):n(Ag + ) being 1. After reacting for 10 min, filter to obtain silver chloride precipitate. The precipitation rate of silver in the leaching solution is 99.2%. First wash the obtained silver chloride precipitate with a nitric acid solution with a pH of 2.5, and then wash it with pure water. The liquid-solid ratio during the washing process is 5:1, the washing temperature is 20 °C, and the purity of the dried silver chloride is 98.6%.

[0064] Then, adjust the pH of the leaching solution after removing silver to about 1, add sodium sulfide with an addition amount of 0.5 g / L, and precipitate for 5 min to obtain metal sulfide precipitate, which can be used as enrichment slag for further metal extraction.

[0065] Finally, add sodium hydroxide to neutralize the Al 3+ -containing solution after impurity removal until the end point pH is 7 and the aging time is 1 h to obtain aluminum hydroxide precipitate. Further wash the aluminum hydroxide precipitate with pure water to remove adsorbed impurity ions, with a washing liquid-solid ratio of 5:1, a washing temperature of 20 °C, and 3 slurry washing times. The purity of the dried aluminum hydroxide is 96.8%.

[0066] Example 3

[0067] First, grind large-sized waste crystalline silicon solar cells to less than 200 μm, leach the powdered cell samples with 6 mol / L nitric acid at a leaching temperature of 80 °C, a leaching liquid-solid mass ratio of 20:1, a leaching time of 3 h, a stirring speed of 400 r / min, an ultrasonic power of 100 W during the leaching process, and filter to obtain a leaching solution containing silver, aluminum, copper and other ions.

[0068] Next, the above-mentioned silicon powder sample was further treated with a 10% HF solution. The reaction time was 20 min, the reaction temperature was room temperature, the leaching liquid-solid ratio was 20:1, and the stirring speed was 300 r / min. Then, the powder sample was washed three times with pure water. The liquid-solid ratio during the washing process was 5:1, the water temperature was room temperature, and the purity of silicon in the dried silicon powder was 99.6%, meeting the requirements of industrial silicon powder.

[0069] Next, sodium chloride was added to the leaching solution, and the molar ratio n(Cl - ):n(Ag + ) was 3. After reacting for 5 min, silver chloride precipitate was obtained by filtration. The precipitation rate of silver in the leaching solution was 99.5%. The obtained silver chloride precipitate was first washed with a nitric acid solution with a pH of 2, and then washed with pure water. The liquid-solid ratio during the washing process was 5:1, the washing temperature was 60 °C, and the purity of the dried silver chloride was 99.4%.

[0070] Then, the pH of the leaching solution after removing silver was adjusted to about 1.5, sodium sulfide was added, and the addition amount was 2 g / L. The precipitation time was 20 min, and metal sulfide precipitate was obtained. This precipitate can be used as enriched slag for further metal extraction.

[0071] Finally, a mixture of sodium hydroxide and sodium carbonate was added to the Al 3+ -containing solution after impurity removal for neutralization. The mass ratio of sodium hydroxide to sodium carbonate was 8:1, the end-point pH of neutralization was 9, and the aging time was 1 h to obtain aluminum hydroxide precipitate. The aluminum hydroxide precipitate was further washed with pure water to remove adsorbed impurity ions. The washing liquid-solid ratio was 10:1, the washing temperature was 80 °C, and the number of slurry washing times was 3 times. The purity of the dried aluminum hydroxide was 99.1%.

[0072] It can be understood that the above embodiments are merely exemplary embodiments adopted to illustrate the principle of the present invention. However, the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also regarded as the protection scope of the present invention.

Claims

1. A method for the coordinated recovery of all elements of crystalline silicon cells of retired photovoltaic modules, characterized in that: The steps include: Step S1, collecting large particles of waste crystalline silicon cells and grinding them into powder; Step S2, leaching the powder with nitric acid, filtering, and obtaining a leachate and impurity-removed silicon powder; wherein the leachate contains silver, aluminum, copper, lead and iron; Step S3, leaching the impurity-removed silicon powder with an HF solution to remove the silicon nitride layer, and filtering, washing, and drying to obtain silicon powder that meets industrial standards; Step S4, subjecting the leachate to chlorination precipitation to obtain silver chloride and the leachate after silver removal, filtering the silver chloride, and then acid-washing-water washing to obtain secondary industrial silver chloride that meets the standards; Step S5, adding sodium sulfide to the leaching solution after silver removal to precipitate the metal therein, and filtering to obtain Al 3+ A solution of; wherein the metals include copper, lead and iron; Step S6, adding Al 3+ Alkaline substances are added to the solution to neutralize and precipitate to form aluminum hydroxide. The aluminum hydroxide precipitate is obtained after filtration. The aluminum hydroxide precipitate is then slurried to remove impurity ions adsorbed on the surface, and the aluminum hydroxide product is obtained after drying.

2. The method for the coordinated recovery of all elements of retired photovoltaic module crystalline silicon cells according to claim 1, characterized in that: In step S1 , the maximum size of the powder is less than 200 μm.

3. The method for the coordinated recovery of all elements of retired photovoltaic module crystalline silicon cells according to claim 1, characterized in that: In step S2, the nitric acid leaching conditions are: the leaching concentration of nitric acid is 3 mol / L-8 mol / L, the leaching time is 1 h-3 h, the leaching temperature is 40° C.-90° C., the leaching liquid-solid ratio is 5:1-20:1, and the stirring speed is 50 r / min-500 r / min.

4. The method for the coordinated recovery of all elements of retired photovoltaic module crystalline silicon cells according to claim 1, characterized in that: In step S2, ultrasound is used during the leaching process to promote the leaching of soluble metals; wherein the ultrasound power is 20W-100W.

5. The method for the coordinated recovery of all elements of retired photovoltaic module crystalline silicon cells according to claim 1, characterized in that: In step S3, the HF solution leaching conditions are: the concentration of the HF solution is 5%-30%, the reaction time is 5min-30min, the reaction temperature is room temperature, the leaching liquid-solid ratio is 5:1-20:1, and the stirring speed is 50r / min-500r / min.

6. The method for the coordinated recovery of all elements of retired photovoltaic module crystalline silicon cells according to claim 1, characterized in that: In step S4, during the chlorination precipitation process, the chloride used includes at least one of sodium chloride, potassium chloride and concentrated hydrochloric acid.

7. The method for the coordinated recovery of all elements of retired photovoltaic module crystalline silicon cells according to claim 1, characterized in that: In step S4, the obtained silver chloride is first washed with dilute nitric acid, and the pH of the dilute nitric acid is 0.8-2.5; then, it is washed with pure water, and the liquid-to-solid ratio during the washing process is 5:1-10:1, and the washing temperature is 20°C-80°C.

8. The method for the coordinated recovery of all elements of retired photovoltaic module crystalline silicon cells according to claim 1, characterized in that: In step S5, the pH of the leaching solution after silver removal is first adjusted to 1-2.5 with NaOH; then, sodium sulfide is added, the amount of sodium sulfide added is 0.5g / L-5g / L, and the precipitation time is 5min-20min.

9. The method for the coordinated recovery of all elements of retired photovoltaic module crystalline silicon cells according to claim 1, characterized in that: In step S6, the alkaline substance includes at least one of sodium hydroxide, potassium hydroxide, ammonia water, sodium carbonate, potassium carbonate, and sodium bicarbonate.

10. The method for full-element synergistic recovery of retired photovoltaic module crystalline silicon cells according to claim 1, characterized in that: In step S6, the liquid-solid ratio of the aluminum hydroxide precipitation slurry washing is 5:1-10:1, the washing temperature is 20°C-80°C, and the slurry washing times are at least 3 times.

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