A kind of waste photovoltaic broken glass cleaning agent and preparation method thereof

Abstract

The invention discloses a cleaning agent for waste photovoltaic broken glass and a preparation method thereof, and relates to the field of glass cleaning agents. The cleaning agent of the invention is mainly used to remove dust, stains and EVA residual glue attached to the surface of photovoltaic broken glass after recycling and disassembly; the preparation method of the cleaning agent comprises the following steps: weighing each component according to the formula of the cleaning agent for waste photovoltaic broken glass, adding the components except water into water, stirring evenly, fully dissolving, and obtaining the glass cleaning agent; in terms of mass percentage, the cleaning agent for waste photovoltaic broken glass comprises: surfactant: 5% to 10%, alkaline solvent: 6% to 14%, co-solvent: 2% to 6%, corrosion inhibitor: 0.5% to 1%, pH regulator: 1% to 3%, water: 66% to 85.5%. When the cleaning agent for waste photovoltaic broken glass provided by the invention is used to soak and clean the broken glass after disassembly of waste photovoltaic, the cleaning rate of both sides of the broken glass can reach more than 98%.

Description

Technical Field

[0001] The invention belongs to the field of glass cleaning agents, and in particular relates to a cleaning agent for waste photovoltaic broken glass and a preparation method thereof. Background Art

[0002] With the rapid development of the photovoltaic power generation industry, the service life of photovoltaic modules is gradually approaching the end, and the recycling and reuse of discarded photovoltaic modules has become an important issue facing the global photovoltaic industry. During the disassembly of photovoltaic modules, materials such as glass, aluminum frames, silicon wafers, and EVA films will be separated and recycled. Among them, photovoltaic glass, as an important component of photovoltaic modules, has high transparency and good mechanical properties. After recycling, it is widely used in remanufacturing and other related industries. However, during the disassembly process, the surface of photovoltaic glass is often attached with a large amount of dust, stains, and EVA film and other pollutants remaining on the back. These pollutants have caused significant obstacles to the subsequent use, remanufacturing and resource recycling of photovoltaic glass.

[0003] EVA film (ethylene-vinyl acetate copolymer film) is the main packaging material in photovoltaic modules. It has strong adhesion and high temperature and UV resistance, and can protect photovoltaic cells from environmental influences. However, during the recycling process of photovoltaic modules, some EVA film may remain on the surface of photovoltaic glass, especially for photovoltaic modules used for a long time in high temperature environment. EVA film may adhere tightly to the glass surface, forming glue marks that are difficult to remove. In addition, a large amount of dust, stains and other pollutants will accumulate during the use of photovoltaic modules. The adhesion of these pollutants not only affects the appearance of photovoltaic glass, but also may affect the processing performance during the subsequent recycling process.

[0004] Existing photovoltaic glass cleaning technologies are mainly concentrated in the production process and on-site cleaning and maintenance of photovoltaic modules. Common cleaning methods include physical wiping, water spraying, and the use of ordinary detergents or solvents. However, for photovoltaic broken glass that is attached with EVA film and stubborn stains after recycling and disassembly, the existing cleaning methods are often ineffective and cannot effectively remove the film residues and accumulated dust and stains. Traditional cleaning agents are usually difficult to dissolve and remove EVA glue residues without damaging the glass surface, and some chemical solvents may corrode or scratch the surface of photovoltaic glass, reducing the utilization value of recycled glass. In addition, there is currently a lack of innovative cleaning agents specifically for the cleaning of photovoltaic broken glass. Most of the existing technologies use general-purpose solvents or cleaning agents, which fail to take into account the special needs faced by photovoltaic broken glass during recycling and reuse.

[0005] Therefore, there is an urgent need for a cleaning agent for dust and EVA adhesive residues attached to the surface of photovoltaic broken glass after recycling and disassembly. The cleaning agent should not only have the ability to efficiently remove EVA adhesive film residues, dust and other pollutants, but also ensure that it does not damage the photovoltaic glass, and can improve the quality of recycled photovoltaic glass, and promote its value maximization in subsequent production or reuse. Developing an efficient cleaning agent for this specific demand will not only help promote the recycling of photovoltaic waste, but also have important significance for environmental protection and resource conservation. Summary of the invention

[0006] The present invention provides a cleaning agent for waste photovoltaic broken glass, which is mainly used to remove dust, stains and EVA residual glue attached to the surface of photovoltaic broken glass after recycling and disassembly. The cleaning agent adopts a series of formulas such as specific surfactants, alkaline solvents, co-solvents, corrosion inhibitors, pH regulators, etc., and by adjusting its chemical composition, concentration and pH, it can efficiently dissolve and remove the difficult-to-remove glue film residues on the surface of photovoltaic broken glass, while avoiding damage to the glass surface. The cleaning agent has strong decontamination ability, mild cleaning effect and good environmental friendliness, can improve the recycling efficiency of waste photovoltaic glass, improve the quality of recycled glass, and thus promote resource reuse and sustainable development in the photovoltaic industry. When the waste photovoltaic broken glass cleaning agent provided by the present invention is used to soak and clean the broken glass after the waste photovoltaic dismantling, the cleaning rate of the front and back sides of the broken glass can reach more than 98%; the preparation method includes mixing surfactants, solvents and other additives in a specific proportion, and obtaining the final product through processes such as dissolution and stirring; the cleaning agent can not only effectively remove EVA glue residues and dust stains during the application process, but also ensure the surface finish and mechanical properties of the photovoltaic broken glass, and avoid the glass surface damage or corrosion problems that may be caused by traditional cleaning methods. The cleaning agent of the present invention can significantly improve the reuse value of waste photovoltaic glass, reduce the waste of resources in the recycling process of photovoltaic modules, and promote the green development of the photovoltaic industry; in summary, the problems in the background technology are solved.

[0007] To solve the above technical problems, the present invention is achieved through the following technical solutions:

[0008] The waste photovoltaic broken glass cleaning agent of the present invention comprises the following components in percentage by mass:

[0009] Surfactant: fatty alcohol polyoxyethylene ether 5.0% to 10.0%;

[0010] Alkaline solvent 1: sodium hydroxide 3.0% to 7.0%;

[0011] Alkaline solvent 2: potassium hydroxide 3.0% to 7.0%;

[0012] Cosolvent: ethanol 2.0% to 6.0%;

[0013] Corrosion inhibitor: sodium nitrate 0.5%~1.0%;

[0014] pH adjuster: citric acid 0.1% to 3.0%;

[0015] Water: 66.0%~86.4%.

[0016] A method for preparing a waste photovoltaic broken glass cleaning agent, which is used to prepare the above-mentioned waste photovoltaic broken glass cleaning agent, comprises the following steps:

[0017] S1. Slowly add sodium hydroxide in small amounts to the potassium hydroxide solution several times according to the corresponding mass percentage, and continue stirring to dissolve it;

[0018] S2. After the mixed solution of sodium hydroxide and potassium hydroxide is fully cooled, some water evaporated due to the heat release of the chemical reaction is added, and then the fatty alcohol polyoxyethylene ether is slowly added to the mixed solution of sodium hydroxide and potassium hydroxide in small amounts and multiple times, and continuously stirred to dissolve it;

[0019] S3, slowly add ethanol in batches and continue stirring to dissolve it;

[0020] S4. Add sodium nitrate while stirring, stirring thoroughly to dissolve;

[0021] S5. Add citric acid to adjust the pH value and stir thoroughly to dissolve;

[0022] S6. Finally, the mixture is allowed to stand and cool to obtain a cleaning agent for waste photovoltaic broken glass.

[0023] Furthermore, after the step S1 is completed, the obtained mixed solution is stirred for more than 30 minutes before the step S2 is performed.

[0024] Furthermore, after the step S2 is completed, the obtained mixed solution is stirred for more than 30 minutes before the step S3 is performed.

[0025] Further, after the step S3 is completed, the obtained mixed solution is stirred for more than 30 minutes and then the step S4 is performed.

[0026] Furthermore, after the step S4 is completed, the obtained mixed solution is stirred for more than 1 hour and then the step S5 is performed.

[0027] Furthermore, the standing time in step S6 is at least 12 hours.

[0028] Furthermore, the steps of preparing the potassium hydroxide mixed solution in step S1 are as follows:

[0029] S11, put the weighed water into a container and start stirring;

[0030] S12. Slowly add potassium hydroxide in small amounts to the aforementioned container several times and continue stirring to dissolve it.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] (1) By selecting raw materials such as sodium hydroxide, potassium hydroxide, ethanol, sodium nitrate, citric acid and water, and accurately controlling the ratio of each component, the prepared cleaning agent exhibits moderate alkalinity. The cleaning agent exhibits excellent performance in effectively removing stains and residues on the surface of photovoltaic broken glass. In addition, the pH adjuster, as one of the core ingredients, can adjust the alkalinity of the cleaning agent as needed to keep it within an optimal pH range, thereby effectively removing EVA film, oil stains and other types of organic pollutants on the surface of photovoltaic broken glass. By adjusting the pH value, the cleaning agent's decontamination ability is significantly improved, thereby optimizing the overall cleaning effect;

[0033] (2) When cleaning recycled photovoltaic broken glass, the mechanism of action of the cleaning agent is to quickly wet and disperse the stains and pollutants attached to the glass surface through a local acid-base reaction with the glass surface. This acid-base reaction can effectively destroy the structure of the EVA film, causing it to quickly dissolve and detach from the glass surface. At the same time, the surfactant in the cleaning agent further helps disperse and emulsify other types of stains and dust by reducing the surface tension of the glass;

[0034] (3) As the molecules in the cleaning agent move violently in the liquid and generate strong impact force, the attached stains and colloidal substances are quickly wetted, dispersed and emulsified, and finally fall off the glass surface. This process allows all kinds of attachments to be completely removed from both sides of the waste photovoltaic broken glass, whether it is organic film, grease, or dust and other pollutants, ensuring that the cleanliness of the photovoltaic glass surface reaches more than 98%;

[0035] (4) The cleaning agent for waste photovoltaic glass of the present invention not only has excellent cleaning effect, but also can protect the glass surface during the cleaning process, avoiding corrosion or damage to the glass that may be caused by traditional cleaning agents. At the same time, the use process of the cleaning agent is simple and convenient, which can effectively improve the efficiency of recycling waste photovoltaic glass, reduce environmental pollution, and help promote the sustainable development of the photovoltaic industry.

[0036] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] A waste photovoltaic broken glass cleaning agent, comprising the following components by mass percentage:

[0039] Surfactant or detergent: fatty alcohol polyoxyethylene ether 5.0% to 10.0%;

[0040] Alkaline solvent 1: sodium hydroxide 3.0% to 7.0%;

[0041] Alkaline solvent 2: potassium hydroxide 3.0% to 7.0%;

[0042] Cosolvent: ethanol 2.0% to 6.0%;

[0043] Corrosion inhibitor: sodium nitrate 0.5%~1.0%;

[0044] pH adjuster: citric acid 0.1% to 3.0%;

[0045] Water: 66.0%~86.4%.

[0046] A method for preparing a waste photovoltaic broken glass cleaning agent, which is used to prepare the above-mentioned waste photovoltaic broken glass cleaning agent, comprises the following steps:

[0047] S1. Slowly add sodium hydroxide in small amounts to the potassium hydroxide solution several times according to the corresponding mass percentage, and continue stirring to dissolve it; after step S1, stir the obtained mixed solution for more than 30 minutes before performing step S2;

[0048] The steps for preparing potassium hydroxide mixed solution are as follows:

[0049] S11, put the weighed water into a container and start stirring;

[0050] S12, slowly adding potassium hydroxide in small amounts to the aforementioned container several times, and continuously stirring to dissolve it;

[0051] S2, after the mixed solution of sodium hydroxide and potassium hydroxide is fully cooled, add part of the water evaporated due to the heat release of the chemical reaction, and then slowly add the fatty alcohol polyoxyethylene ether to the mixed solution of sodium hydroxide and potassium hydroxide in small amounts and multiple times, and continue to stir to dissolve it; after the end of step S2, stir the obtained mixed solution for more than 30 minutes and then proceed to step S3;

[0052] S3, slowly adding ethanol in batches and continuously stirring to dissolve it; after step S3, stirring the obtained mixed solution for more than 30 minutes and then proceeding to step S4;

[0053] S4, adding sodium nitrate while stirring, stirring thoroughly to dissolve; after step S4, stirring the resulting mixed solution for more than 1 hour and then proceeding to step S5;

[0054] S5. Add citric acid to adjust the pH value and stir thoroughly to dissolve;

[0055] S6. Finally, the solution is allowed to stand and cool to obtain a cleaning agent for waste photovoltaic broken glass. The standing time is at least 12 hours.

[0056] Embodiment 1:

[0057] This embodiment provides a waste photovoltaic broken glass cleaning agent and a preparation method thereof.

[0058] The formula of the waste photovoltaic broken glass cleaning agent provided in this embodiment is shown in Table 1, and the content of each component is expressed in mass percentage.

[0059] The method for producing 100 kg of the above-mentioned waste photovoltaic broken glass cleaning agent is as follows:

[0060] (1) Weigh 85.5 kg of tap water and place it in a stirring reaction vessel, and stir it;

[0061] (2) Weigh 3 kg of potassium hydroxide and slowly add it into the reaction container in small amounts and multiple times, while stirring;

[0062] (3) Weigh 3 kg of sodium hydroxide and slowly add it into the reaction container in small amounts and multiple times, and stir;

[0063] (4) replenishing some of the water evaporated due to heat release from chemical reactions;

[0064] (5) Weigh 5 kg of fatty alcohol polyoxyethylene ether, slowly add it into the alkaline solution, and continue stirring to fully dissolve it;

[0065] (6) Weigh 2 kg of ethanol and slowly add it to the liquid alkali solution, stirring continuously to fully dissolve it;

[0066] (7) Add 0.5 kg of sodium nitrate slowly in batches while stirring, and continue stirring to fully dissolve;

[0067] (8) Add 1 kg of citric acid while stirring and stir thoroughly to dissolve for 1 hour;

[0068] (9) After standing for 12 hours and cooling, the waste photovoltaic broken glass cleaning agent is obtained.

[0069] Take some of the prepared waste photovoltaic cullet cleaning agent, and use the cleaning solution to clean the disassembled and recycled waste photovoltaic cullet according to the specified soaking and cleaning process, and soak for 6 hours. After soaking and cleaning, the waste photovoltaic cullet is observed to have no corrosion, no spots, no detergent residue on the surface, and a good cleaning effect. The water droplet is measured to be 45°. By counting the proportion of qualified waste photovoltaic cullet, it can be concluded that the cleaning rate of both sides of the cullet reaches 98%.

[0070] Element content Fatty alcohol polyoxyethylene ether 5.0％ Sodium hydroxide 3.0％ Potassium hydroxide 3.0％ Ethanol 2.0％ Sodium nitrate 0.5％ Citric Acid 1.0％ water 85.5％

[0071] Table 1: Formula of the waste photovoltaic broken glass cleaning agent in Example 1

[0072] Embodiment 2:

[0073] This embodiment provides a waste photovoltaic broken glass cleaning agent and a preparation method and application thereof.

[0074] The formula of the waste photovoltaic broken glass cleaning agent provided in this embodiment is shown in Table 2, and the content of each component is expressed in mass percentage.

[0075] The method for producing 100 kg of the above-mentioned waste photovoltaic broken glass cleaning agent is as follows:

[0076] (1) Weigh 76.3 kg of tap water and place it in a stirring reaction vessel, and stir it;

[0077] (2) Weigh 5 kg of potassium hydroxide and slowly add it into the reaction container in small amounts and multiple times, while stirring;

[0078] (3) Weigh 5 kg of sodium hydroxide and slowly add it into the reaction container in small amounts and multiple times, and stir;

[0079] (4) replenishing some of the water evaporated due to heat release from chemical reactions;

[0080] (5) Weigh 7 kg of fatty alcohol polyoxyethylene ether, slowly add it into the alkaline solution, and continue stirring to fully dissolve it;

[0081] (6) Weigh 4 kg of ethanol and slowly add it to the liquid alkali solution, stirring continuously to fully dissolve it;

[0082] (7) Add 0.7 kg of sodium nitrate slowly in batches while stirring, and continue stirring to fully dissolve;

[0083] (8) Add 2.0 kg of citric acid while stirring and stir thoroughly to dissolve for 1 hour;

[0084] (9) After standing for 12 hours and cooling, the waste photovoltaic broken glass cleaning agent is obtained.

[0085] Take some of the prepared waste photovoltaic cullet cleaning agent, and use the cleaning solution to clean the disassembled and recycled waste photovoltaic cullet according to the specified soaking and cleaning process, and soak for 6 hours. After soaking and cleaning, the waste photovoltaic cullet is observed to have no corrosion, no spots, no detergent residue on the surface, and a good cleaning effect. The water droplet is measured to be 45°. By counting the proportion of qualified waste photovoltaic cullet, it can be concluded that the cleaning rate of both sides of the cullet reaches 99%.

[0086] Element content Fatty alcohol polyoxyethylene ether 7.0％ Sodium hydroxide 5.0％ Potassium hydroxide 5.0％ Ethanol 4.0％ Sodium nitrate 0.7％ Citric Acid 2.0％ water 76.3％

[0087] Table 2: Formula of the waste photovoltaic broken glass cleaning agent in Example 2

[0088] Embodiment 3:

[0089] This embodiment provides a waste photovoltaic broken glass cleaning agent and a preparation method and application thereof.

[0090] The formula of the waste photovoltaic broken glass cleaning agent provided in this embodiment is shown in Table 3, and the content of each component is expressed in mass percentage.

[0091] The method for producing 100 kg of the above-mentioned waste photovoltaic broken glass cleaning agent is as follows:

[0092] (1) Weigh 66.0 kg of tap water and place it in a stirring reaction vessel, and stir it;

[0093] (2) Weigh 7 kg of potassium hydroxide and slowly add it into the reaction container in small amounts and multiple times, while stirring;

[0094] (3) Weigh 7 kg of sodium hydroxide and slowly add it into the reaction container in small amounts and multiple times, and stir;

[0095] (4) replenishing some of the water evaporated due to heat release from chemical reactions;

[0096] (5) Weigh 10 kg of fatty alcohol polyoxyethylene ether, slowly add it into the alkaline solution, and continue stirring to fully dissolve it;

[0097] (6) Weigh 6 kg of ethanol and slowly add it to the liquid alkali solution, stirring continuously to fully dissolve it;

[0098] (7) Add 1 kg of sodium nitrate slowly in batches while stirring, and continue stirring to fully dissolve;

[0099] (8) Add 3 kg of citric acid while stirring and stir thoroughly to dissolve for 1 hour;

[0100] (9) After standing for 12 hours and cooling, the waste photovoltaic broken glass cleaning agent is obtained.

[0101] Take some of the prepared waste photovoltaic cullet cleaning agent, and use the cleaning solution to clean the disassembled and recycled waste photovoltaic cullet according to the specified soaking and cleaning process, and soak for 6 hours. After soaking and cleaning, the waste photovoltaic cullet is observed to have no corrosion, no spots, no detergent residue on the surface, and a good cleaning effect. The water droplet is measured to be 45°. By counting the proportion of qualified waste photovoltaic cullet, it can be concluded that the cleaning rate of both sides of the cullet reaches 98%.

[0102] Element content Fatty alcohol polyoxyethylene ether 10.0％ Sodium hydroxide 7.0％ Potassium hydroxide 7.0％ Ethanol 6.0％ Sodium nitrate 1.0％ Citric Acid 3.0％ water 66.0％

[0103] Table 3: Formula of the waste photovoltaic broken glass cleaning agent in Example 3

[0104] The present invention selects raw materials such as sodium hydroxide, potassium hydroxide, ethanol, sodium nitrate, citric acid and water, and accurately controls the ratio of each component, so that the prepared cleaning agent exhibits moderate alkalinity. The cleaning agent shows excellent performance in effectively removing stains and residues on the surface of photovoltaic broken glass. In addition, the pH regulator, which is one of the core components, can adjust the alkalinity of the cleaning agent according to demand to keep it within an optimal pH value range, thereby effectively removing EVA film, oil stains and other types of organic pollutants on the surface of photovoltaic broken glass. By adjusting the pH value, the decontamination ability of the cleaning agent is significantly improved, thereby optimizing the overall cleaning effect;

[0105] When cleaning recycled photovoltaic broken glass, the mechanism of action of the cleaning agent is to quickly wet and disperse the stains and pollutants attached to the glass surface through a local acid-base reaction with the glass surface. This acid-base reaction can effectively destroy the structure of the EVA film, causing it to quickly dissolve and detach from the glass surface. At the same time, the surfactant in the cleaning agent further helps disperse and emulsify other types of stains and dust by reducing the surface tension of the glass;

[0106] Because the molecules in the cleaning agent will move violently in the liquid, generating a strong impact force, these attached stains and colloidal substances are quickly wetted, dispersed and emulsified, and finally fall off the glass surface. This process allows the front and back sides of the waste photovoltaic broken glass to be completely free of various attachments, whether organic film, grease, or dust and other pollutants, ensuring that the cleanliness of the photovoltaic glass surface reaches more than 98%;

[0107] The cleaning agent for waste photovoltaic broken glass of the present invention not only has excellent cleaning effect, but also can protect the glass surface during the cleaning process, avoiding corrosion or damage to the glass caused by traditional cleaning agents. At the same time, the cleaning agent is simple and convenient to use, can effectively improve the efficiency of recycling waste photovoltaic glass, reduce environmental pollution, and help promote the sustainable development of the photovoltaic industry.

[0108] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A waste photovoltaic broken glass cleaning agent, characterized in that: In terms of mass percentage, it includes the following components: Surfactant: fatty alcohol polyoxyethylene ether 5.0% to 10.0%; Alkaline solvent 1: sodium hydroxide 3.0% to 7.0%; Alkaline solvent 2: potassium hydroxide 3.0% to 7.0%; Cosolvent: ethanol 2.0% to 6.0%; Corrosion inhibitor: sodium nitrate 0.5%~1.0%; pH regulator: citric acid 0.1% to 3.0%; Water: 66.0%~86.4%.

2. A method for preparing a waste photovoltaic cullet cleaning agent, which is used to prepare the waste photovoltaic cullet cleaning agent according to claim 1, characterized in that: The steps include: S1. Slowly add sodium hydroxide in small amounts to the potassium hydroxide solution several times according to the corresponding mass percentage, and continue stirring to dissolve it; S2. After the mixed solution of sodium hydroxide and potassium hydroxide is fully cooled, some water evaporated due to the heat release of the chemical reaction is added, and then the fatty alcohol polyoxyethylene ether is slowly added to the mixed solution of sodium hydroxide and potassium hydroxide in small amounts and multiple times, and continuously stirred to dissolve it; S3, slowly add ethanol in batches and continue stirring to dissolve it; S4. Add sodium nitrate while stirring, stirring thoroughly to dissolve; S5. Add citric acid to adjust the pH value and stir thoroughly to dissolve; S6. Finally, the mixture is allowed to stand and cool to obtain a cleaning agent for waste photovoltaic broken glass.

3. The method for preparing a waste photovoltaic broken glass cleaning agent according to claim 2, characterized in that: After the step S1 is completed, the obtained mixed solution is stirred for more than 30 minutes and then the step S2 is performed.

4. The method for preparing a waste photovoltaic broken glass cleaning agent according to claim 2, characterized in that: After the step S2 is completed, the obtained mixed solution is stirred for more than 30 minutes and then the step S3 is performed.

5. The method for preparing a waste photovoltaic broken glass cleaning agent according to claim 2, characterized in that: After the step S3 is completed, the obtained mixed solution is stirred for more than 30 minutes and then the step S4 is performed.

6. The method for preparing a waste photovoltaic broken glass cleaning agent according to claim 2, characterized in that: After the step S4 is completed, the obtained mixed solution is stirred for more than 1 hour and then the step S5 is performed.

7. The method for preparing a waste photovoltaic broken glass cleaning agent according to claim 2, characterized in that: The standing time in step S6 is at least 12 hours.

8. The method for preparing a waste photovoltaic broken glass cleaning agent according to claim 2, characterized in that: The steps for preparing the potassium hydroxide mixed solution in step S1 are as follows: S11, put the weighed water into a container and start stirring; S12. Slowly add potassium hydroxide in small amounts to the aforementioned container several times and continue stirring to dissolve it.