Material criticality evaluation method for waste photovoltaic panel low-carbon recovery technology

Abstract

The invention provides a material criticality evaluation method for a waste photovoltaic panel low-carbon recovery technology, which comprises the following steps: collecting raw material information of waste photovoltaic panels, raw materials comprising at least one of metal, organic matters and inorganic non-metallic materials; evaluating key indexes of various types of raw materials in the waste photovoltaic panel; the production carbon emission factor and the recycling carbon emission factor of each type of raw materials are determined, and the material benefit and the carbon emission reduction benefit in the recycling process are determined in combination with the key index, the recycling rate, the production carbon emission factor and the recycling carbon emission factor of each type of raw materials; and key differences of different photovoltaic panel types are analyzed, and a quantitative basis is provided for selection of a recovery scheme. According to the invention, key analysis of various raw materials in different types of photovoltaic panels is realized; and meanwhile, calculation of material benefits and carbon emission reduction benefits is introduced, and collaborative development of resources and the environment is promoted by comparing the material benefits and the carbon emission reduction benefits in the recovery process of different types of photovoltaic panels.

Description

Technical Field

[0001] This invention relates to the field of waste photovoltaic panel recycling and evaluation technology, and more specifically, to a material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels. Background Technology

[0002] With the rapid development of the global photovoltaic industry, the amount of waste generated after the retirement of photovoltaic panels is increasing daily, making the research and application of waste photovoltaic panel treatment technologies increasingly important. However, photovoltaic panels typically have a lifespan of 25-30 years, resulting in a large amount of waste after retirement. Improper disposal of waste photovoltaic panels can pose environmental risks, such as the potential for hazardous substance leakage and soil and water pollution through landfilling.

[0003] Meanwhile, photovoltaic panels contain recyclable materials, and proper processing can achieve resource recycling, reduce environmental impact, and promote the sustainable development of the photovoltaic industry. Photovoltaic modules are composed of recyclable materials such as glass, aluminum, silicon, copper, and silver, possessing certain recycling value. Glass recycling can reduce energy consumption by 32%, recycled copper has carbon emissions only 25.7% of those of refined copper, and recycled aluminum has carbon dioxide emissions only 4.6% of those of virgin aluminum. Recycling used modules can achieve resource recycling, avoiding the land occupation and environmental pollution caused by traditional landfill or incineration methods, reducing carbon emissions from virgin material production, and effectively addressing the upcoming wave of module retirements in my country.

[0004] Recycling technologies mainly include physical, chemical, and pyrolysis methods. Physical processing can separate some components but may result in the loss of rare elements; chemical processing can further recover elements such as metals, but chemical solutions require proper handling; pyrolysis can reduce the carbon footprint, but it presents challenges such as high temperatures, high energy consumption, and difficulties in product processing. Different recycling technologies yield varying recovery rates for different types of photovoltaic panels, necessitating the establishment of an evaluation method to assess the material sustainability and carbon reduction benefits during the recycling process, promote the improvement of key material recovery rates, and drive the development of recycling technologies. Summary of the Invention

[0005] In view of this, the present invention proposes a material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels, aiming to solve the above-mentioned technical problems existing in the prior art.

[0006] This invention proposes a material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels, including:

[0007] Collect information on the raw materials of waste photovoltaic panels, wherein the raw materials include at least one of metals, organic matter and inorganic non-metallic materials;

[0008] Assess the key indicators of each type of raw material in the waste photovoltaic panels;

[0009] Determine the production carbon emission factor and recycling carbon emission factor for each type of raw material, and combine the key indicators, recovery rate, production carbon emission factor and recycling carbon emission factor for each type of raw material to determine the material benefits and carbon emission reduction benefits in the recycling process;

[0010] Based on the above assessment and calculation results, the key differences between different photovoltaic panel types and recycling technologies are analyzed to provide a quantitative basis for the selection of recycling solutions.

[0011] Furthermore, in the above-mentioned material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels, the total criticality index of the metal raw materials is determined by the following formula:

[0012] t i =CR mi ×m i In the formula, t i CR represents the total critical index of the i-th metal; mi This represents the key indicator for the i-th metal; m i Let i represent the mass of the metal, i be a natural number, and i ≥ 1, representing different types of metal raw materials.

[0013] Furthermore, in the aforementioned material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels, the comprehensive criticality index CR of the metal is... m Determined by the following formula:

[0014] CR m =SR×EI

[0015] EI=(∑S×GVA) / GVA est ×SI EI ×10

[0016]

[0017] Among them, CR m The overall criticality of a metal is indicated by: SR (Comprehensive Criticality); EI (Supply Risk); S (Economic Importance); GVA (Demand Share of Metal Raw Materials); SI (Market Value of Metals); and WGI (World Governance Index). (HHIWGI) GS The Herfindahl-Hirschman Index (HHIWGI) is a global index based on the World Governance Index. CN This refers to the Herfindahl-Hirschman Index for China, which is based on the World Governance Index.

[0018] Furthermore, in the aforementioned material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels, the key indicators of the organic matter are determined by the following formula:

[0019]

[0020] Among them, CR o For key indicators of organic matter, r1, r2, r3, r4, and r5 represent the potential hazard index, toxicity level index, bioaccumulation index, photochemical reactivity index, and environmental persistence index, respectively; d1, d2, d3, d4, and d5 represent the potential hazard, toxicity level, bioaccumulation, photochemical reactivity, and environmental persistence, respectively; parameter r i The requirements are Wherein: d1, d2, d3, d4, and d5 are 0.37, 0.18, 0.1, 0.2, and 0.15, respectively.

[0021] Furthermore, in the aforementioned material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels, r i Determined by the following formula:

[0022] P = 2b1b1′B1 + 4b2B2

[0023] AMEG AH =0.107×LD 50

[0024]

[0025] In the formula, P is the potential hazard index value, B1 is the environmental target value for general chemical substances across multiple media, B2 is the environmental target value for hazardous chemical substances across multiple media, and B1, b1′, and B2 are constant terms; if a B2 value can be found, then b1 = 1; if a B2 value cannot be found, then b1 = 2; b1′ = 1.25 is used for the accumulation or chronic toxicity of chemical substances, and b1′ = 1 is only used for acute toxicity; when B1 is found, b2 = 1; when B1 cannot be found, b2 = 1.5; LD 50 This represents the median lethal dose for oral toxicity in rats or imported mice.

[0026] Furthermore, in the above-mentioned material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels, among the inorganic non-metallic materials, the criticality index of glass is 1, the criticality index of air is 0.33, the criticality index of synthesis or processing gas is set to 0.67, and the criticality index of special gas is 1.

[0027] Furthermore, in the aforementioned material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels, the material benefits and emission reduction benefits during the recycling process of different types of photovoltaic panels are determined by the following formula:

[0028] t ri =∑CR mi ×m i×EOL Rmi +∑CR oi ×m i ×EOL Roi +∑CR ai ×m i ×EOL Rai

[0029] CE=∑(E vi -E ri )×m i ×EOL Ri

[0030] In the formula, t ri Indicates the benefits of recycling materials; CR mi Represents the key indicators of the i-th metallic material; CR oi Represents the key indicators of the i-th type of organic material; CR ai The key performance indicator for the i-th material is represented by CE; carbon emission reduction benefit is represented by Evi; carbon emission factor during the production process of the i-th raw material is represented by Eri; and m represents the carbon emission factor during the recycling process of the i-th raw material is represented by Eri. i Let EOL represent the quality of the i-th type of raw material, where i is the raw material, i is a natural number, and i≥1, representing different types of raw materials; Rmi EOL represents the recovery rate of the i-th metal material in the photovoltaic panel recycling process; Roi EOL represents the recovery rate of the i-th organic compound in the photovoltaic panel recycling process; Rai EOL represents the recovery rate of the i-th inorganic non-metallic material in the photovoltaic panel recycling process; Ri This represents the recovery rate of the i-th raw material in the photovoltaic panel recycling process.

[0031] This invention provides a material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels. Through quantitative formulas, it achieves precise assessment of the criticality of materials in different types of photovoltaic panels and recycling technologies. In the assessment of metallic materials, it integrates multi-dimensional indicators such as supply risk and economic importance, and incorporates parameters such as the World Governance Index to deeply analyze the supply stability of metals in global and domestic markets. For organic materials, it uses weighted calculations based on indices such as potential hazard and toxicity level to accurately measure their environmental impact, providing a reliable basis for recycling decisions. Simultaneously, it incorporates material recycling rates into the calculation of material benefits and carbon reduction benefits, promoting the coordinated development of resources and the environment by comparing the material benefits and carbon reduction benefits of different recycling technologies. Attached Figure Description

[0032] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0033] Figure 1 This is a schematic flowchart of a material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels provided in an embodiment of the present invention;

[0034] Figure 2 The result diagram of key indicators of metallic materials in the material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels provided in the embodiments of the present invention;

[0035] Figure 3 The key results of organic materials in the material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels provided in the embodiments of the present invention;

[0036] Figure 4 The key results diagram of inorganic non-metallic materials in the material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels provided in the embodiments of the present invention is shown.

[0037] Figure 5 The diagram shows the results of material benefits and carbon emission reduction benefits during the recycling process in the material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels provided in the embodiments of the present invention. Detailed Implementation

[0038] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0039] See Figure 1 The material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels according to embodiments of the present invention includes:

[0040] Step S1: Collect raw material information of waste photovoltaic panels, wherein the raw materials include at least one of metals, organic matter and inorganic non-metallic materials.

[0041] Specifically, the inorganic non-metallic material includes photovoltaic module encapsulation materials (e.g., glass) and functional gases (synthetic or processing gases or specialty gases).

[0042] Step S2: Evaluate the key indicators of each type of raw material in the waste photovoltaic panels.

[0043] (1) The total criticality of metallic raw materials is determined by the following formula:

[0044] t i =CR mi ×m i

[0045] In the formula, t i Represents the total key performance indicator (CR) for metal i; mi This represents the key indicator for the i-th metal; m i Let i represent the mass of the metal, i be a natural number, and i ≥ 1, representing different types of metal raw materials.

[0046] The comprehensive key indicators of metallic materials are determined by the following formula:

[0047] CR m =SR×EI

[0048] In the formula, CR m This represents the overall key performance indicator (KPI) for metallic materials; SR represents supply risk; and EI represents economic importance. Among these:

[0049] EI=(∑S×GVA) / GVA est ×SI EI ×10

[0050]

[0051] In the formula, S represents the demand share of metal raw materials, and GVA represents the market value of the metal. est SI represents the estimated market value of a metal within the entire market or economy; WGI represents the World Governance Index. WGI ) GS This refers to the global Herfindahl-Hirschman Index (HHI), which is based on the World Governance Index. WGI ) CN The Chinese Herfindahl-Hirschman Index is based on the World Governance Index; IR represents import dependence; EOL represents import dependence. RIR The recycling rate of metallic materials across the entire market.

[0052] ΣS×GVA represents the sum of the products of the demand (S) for the metal from all relevant industries or sectors and its market value (GVA).

[0053] GVA est It represents the estimated market value of the metal in the entire market or economy.

[0054] SI refers to the sustainability of metals; SI EI Indicates the sustainability of metals based on economic importance; SI SR This refers to the sustainability of metals based on supply risk.

[0055]

[0056] In the formula, WGI GS The World Governance Index (WGI) represents global supply. CN The World Governance Index (S) represents China's global governance index. GS Indicates global market share; S CN This indicates China's market share.

[0057] The key calculation results for metallic materials are as follows: Figure 2 (Table 1-4) shows that Si has the highest criticality in x-Si, while Cu has the highest criticality in CdTe and CIGS. Silicon, as a major component of photovoltaic panels, has a huge market demand, but due to its high recycling rate and low import dependence, the supply risk is only 0.09, making its overall criticality relatively controllable. Copper, as a conductive material, is widely used in photovoltaic panels, and its overall criticality is the highest (CR). m =3.40). In contrast, rare metals such as gallium and indium, due to their high dependence on imports and complex recycling processes, have supply risks of 1.66 and 2.50 respectively, highlighting the instability of resource supply. The results indicate that in promoting photovoltaic panel recycling, it is crucial to focus on the recycling efficiency of critical metals, while simultaneously reducing import dependence on rare metals through technological innovation to achieve the dual goals of resource security and environmental benefits. Furthermore, for metals with high supply risks such as cadmium and tellurium, it is necessary to continuously improve the recycling system and develop alternative materials to promote the long-term stable development of the photovoltaic industry.

[0058] Table 1 EI values ​​of metals

[0059]

[0060] Table 2 SR values ​​of metals

[0061]

[0062] Table 3 CR of metals m value

[0063]

[0064] Table 4. Critical t-values ​​for metallic materials

[0065]

[0066] As can be seen from Table 3, the CRm values ​​of each metal are the same during the recycling process of different types of photovoltaic panels; as can be seen from Table 4, the t value, as an indicator that comprehensively reflects the overall effect of the entire recycling process, can be compared.

[0067] (2) Key indicators of organic matter:

[0068]

[0069] In the formula, CR o For key indicators of organic matter, r1, r2, r3, r4, and r5 represent the potential hazard index, toxicity level index, bioaccumulation index, photochemical reactivity index, and environmental persistence index, respectively; d1, d2, d3, d4, and d5 represent the potential hazard, toxicity level, bioaccumulation, photochemical reactivity, and environmental persistence, respectively. In the above formula, the parameter r... i The requirements are Wherein: d1, d2, d3, d4, and d5 are 0.37, 0.18, 0.1, 0.2, and 0.15, respectively.

[0070] P = 2b1b1′B1 + 4b2B2

[0071] AMEG AH =0.107×LD 50

[0072]

[0073] In the formula, P is the potential hazard index value, and B1 is the AMEG (Advanced Mechanism of Chemical Substances). AH The environmental target values ​​for multiple media, B2 represents hazardous chemicals (AMEG). AC The environmental target values ​​for multiple media are defined as follows: b1, b1′, and b2 are constants. If a value for B2 is found, then b1 = 1; if a value for B2 is not found, then b1 = 2; b1′ = 1.25 is used for the accumulation or chronic toxicity of chemical substances, and b1′ = 1 is only used for acute toxicity; when B1 is found, b2 = 1; when B1 is not found, b2 = 1.5. Where LD... 50 This refers to the median lethal dose for oral toxicity in rats (or imported mice). ACGIH refers to the workplace air concentration standards established by the American Conference of American Industrial Hygiene Scientists (ACGIH).

[0074] In practice, the expression for the potential hazard index value P can be determined based on the known properties and toxicity types of B1 and B2. For example, the following situations:

[0075] If B2 is known, then b1 = 1; if the toxicity is chronic, then b1' = 1.25; in this case, if B1 is known, then b2 = 1, therefore: P = 2 × 1 × 1.25 × B1 + 4 × 1 × B2 = 2.5B1 + 4B2

[0076] If B2 is known, then b1 = 1; if the toxicity is chronic, then b1' = 1.25; in this case, if B1 is unknown, then b2 = 1.5. Therefore: P = 2 × 1 × 1.25 × B1 + 4 × 1.5 × B2 = 2.5B1 + 6B2

[0077] If B2 is known, then b1 = 1; if the toxicity is acute, then b1' = 1; in this case, if B1 is unknown, then b2 = 1.5. Therefore: P = 2 × 1 × 1 × B1 + 4 × 1.5 × B2 = 2B1 + 6B2

[0078] If B2 is known, then b1 = 1; if the toxicity is acute, then b1' = 1; in this case, if B1 is known, then b2 = 1, therefore: P = 2 × 1 × 1 × B1 + 4 × 1 × B2 = 2B1 + 4B2

[0079] If B2 is unknown, then b1 = 2; if the toxicity is chronic, then b1' = 1.25; in this case, if B1 is known, then b2 = 1; therefore: P = 2 × 2 × 1.25 × B1 + 4 × 1 × B2 = 5B1 + 4B2

[0080] If B2 is unknown, then b1 = 2; if the toxicity is chronic, then b1' = 1.25; in this case, if B1 is unknown, then b2 = 1.5; therefore: P = 2 × 2 × 1.25 × B1 + 4 × 1.5 × B2 = 5B1 + 6B2

[0081] If B2 is unknown, then b1 = 2; if the toxicity is acute, then b1' = 1; in this case, if B1 is known, then b2 = 1; therefore: P = 2 × 2 × 1 × B1 + 4 × 1 × B2 = 4B1 + 4B2

[0082] If B2 is unknown, then b1 = 2; if the toxicity is acute, then b1' = 1; in this case, if B1 is unknown, then b2 = 1.5; therefore: P = 2 × 2 × 1 × B1 + 4 × 1.5 × B2 = 4 B1 + 6 B2; if both B1 and B2 are unknown, then their values ​​are 0.

[0083] Based on the calculated P, determine the ranges for the potential hazard index r1, toxicity index r2, bioaccumulation index r3, photochemical reactivity index r4, and environmental persistence index r5 of the organic matter in Table 4 below:

[0084] Table 4 Potential Hazard Index, Toxicity Index, Bioaccumulation Index, Photochemical Reactivity Index, and Environmental Persistence Index

[0085]

[0086]

[0087] Among them: the range of potential hazard (P), the range of toxicity level (LD50), and the range of bioaccumulation (lgK). ow Range (Shang, Z., He, S., 2012. Comparative study on the prediction software of distribution coefficient of organic pollutants (N-octanol / water). Sci. Technol. Guide 30(19), 63 69.), range of photochemical reactivity as MIR (Wu, L., Wang, X., Yang, W., GUO, F., Liu, J., 2018. Ozone formation potential and optimal control species of VOCs in an industrial park. Environ. Sci. 39(02), 511-516.), range of environmental persistence as DT50 (list of organic half-lives).

[0088] Based on the above indices, the CRo of the following organic compounds was determined:

[0089] Table 5. CRo values ​​of organic compounds

[0090]

[0091] In this embodiment, by using key indicators such as the toxicity and bioaccumulation of organic matter, the hazards of various organic materials are identified, and they can be selectively and efficiently treated to achieve harmlessness.

[0092] Key results of organic materials, such as Figure 3(Table 5-6) The total organic material criticality of x-Si is significantly higher than that of CdTe and CIGS, while the total organic material criticality of CdTe and CIGS is similar. EVA has the highest criticality in x-Si, directly related to its widespread use as a primary encapsulation material. The criticality of PVDF, PET, PE, and PA decreases in that order, perfectly aligning with their functional roles and usage in modules. In CdTe and CIGS, the criticality of EVA is lower than in x-Si, reflecting the different encapsulation material requirements of thin-film technology. PVDF is significantly more critical than x-Si in CdTe and CIGS due to its specific application in the backsheet of thin-film modules. Material criticality analysis can provide a more precise basis for material selection for the sustainable development of the photovoltaic industry.

[0093] Table 6 Material Criticality t-values ​​of Organic Compounds

[0094]

[0095] (3) Key indicators of inorganic non-metallic materials

[0096] Inorganic non-metallic materials include photovoltaic module encapsulation materials (such as glass) and functional gases. Inorganic materials in waste photovoltaic panels, such as glass, have no significant resource or pollution effects, so their material criticality index (CR) is... ai Set to 1. For the CR (Cr Regulator) of air, synthesis or processing gases (such as nitrogen, carbon dioxide, etc.) and specialty gases (such as silane, nitrogen trifluoride, argon, etc.) involved in the photovoltaic panel recycling process... ai The values ​​were set to 0.33, 0.67, and 1, respectively. These settings remain relatively stable across different types of photovoltaic panels and recycling technologies, and are primarily used to comprehensively consider the overall criticality of all materials in the recycling process of waste photovoltaic panels.

[0097] Key results of inorganic non-metallic materials, such as Figure 4 (Table 7) shows that the criticality t-values ​​of glass in CdTe and CIGS are higher than those in x-Si. This indicates a difference in the criticality of glass among different types of photovoltaic modules. Although the criticality of glass itself is relatively low, its high content in modules implies a massive amount requiring recycling. Therefore, developing efficient glass separation and purification technologies is crucial for reducing overall recycling costs.

[0098] Table 7 Material Criticality t-values ​​for Inorganic Non-metallic Materials

[0099]

[0100] Step S3: Determine the production carbon emission factor and recycling carbon emission factor for each type of raw material, and combine the key indicators, recovery rate, production carbon emission factor and recycling carbon emission factor of each type of raw material to determine the material benefits and carbon emission reduction benefits in the recycling process.

[0101] Specifically, different recycling technologies recycle different types of photovoltaic panels, and the recovery rates of various materials vary significantly. By comparing the recovery rates of raw materials, a more detailed comparison of the benefits of material recycling and carbon reduction can be made. The calculation formula is as follows:

[0102] t ri =∑CR mi ×m i ×EOL Rmi +∑CR oi ×m i ×EOL Roi +∑CR ai ×m i ×EOL Rai

[0103] CE=∑(E vi -E ri )×m i ×EOL Ri

[0104] In the formula, t ri Indicates the benefits of recycling materials; CR mi Represents the key indicators of the i-th metallic material; CR oi Represents the key indicators of the i-th type of organic material; CR ai The key performance indicator for the i-th material is represented by CE; carbon emission reduction benefit is represented by Evi; carbon emission factor during the production process of the i-th raw material is represented by Eri; and m represents the carbon emission factor during the recycling process of the i-th raw material is represented by Eri. i Let EOL represent the quality of the i-th type of raw material, where i is the raw material, i is a natural number, and i≥1, representing different types of raw materials; Rmi EOL represents the recovery rate of the i-th metal material in the photovoltaic panel recycling process; Roi EOL represents the recovery rate of the i-th organic compound in the photovoltaic panel recycling process; Rai EOL represents the recovery rate of the i-th inorganic non-metallic material in the photovoltaic panel recycling process; Ri This represents the recovery rate of the i-th raw material in the photovoltaic panel recycling process.

[0105] Benefits of recycling materials ri It is by analyzing the key indicator CR of each raw material mi Its mass m i and material recycling rate (EOL) RiThe product is obtained by multiplying and then summing. This reflects the economic benefits brought about by the recycling process of different raw materials.

[0106] Carbon emission reduction benefit (CE) is calculated by multiplying the difference between the carbon emission factor (Evi) of each raw material during the production process and the carbon emission factor (Eri) during the recycling process by the mass (m) of that raw material. i and material recycling rate (EOL) Ri The summation is the final result. This represents the reduction in carbon emissions through recycling.

[0107] The benefits of recycling materials and carbon reduction are as follows: Figure 5 (Tables 8-9). The results show that different photovoltaic modules differ significantly in terms of material recycling value and carbon reduction. x-Si exhibits significant advantages in recycling and carbon reduction. The recycling benefits of CdTe and CIGS are relatively limited. Although rare elements such as tellurium in CdTe and indium in CIGS modules have special value, these materials account for a very low percentage of the module's mass.

[0108] By calculating and prioritizing evaluation methods, the study identified strategic materials such as copper and silicon that require priority protection, as well as high-risk rare metals such as gallium and indium that urgently need technological breakthroughs. At the same time, the environmental treatment priority of packaging materials such as EVA was quantitatively analyzed, providing a clear direction for optimizing recycling processes.

[0109] Table 8. Material benefits and emission reduction benefits of recycling different photovoltaic panel materials

[0110]

[0111] Table 9. Material benefits and emission reduction benefits of different recycling technologies for x-Si.

[0112]

[0113] Step S4: Based on the above assessment and calculation results, analyze the key differences between different photovoltaic panel types and recycling technologies to provide a quantitative basis for the selection of recycling solutions.

[0114] Specifically, the key differences between different types of photovoltaic panels mainly lie in the strategic value of metallic materials and the environmental risks of organic matter. x-Si uses silicon and copper as core materials. While silicon has high market demand, its supply risk is low. Copper, due to its widespread use in conductive components, has the highest overall criticality. Its high recycling rate and significant carbon reduction potential give x-Si a clear advantage in recycling efficiency. In contrast, cadmium and tellurium in CdTe, although facing extremely high supply risks, have lower economic importance, resulting in limited overall recycling value. Rare metals such as indium and gallium in CIGS are highly dependent on imports. Although their criticality scores are not high, their strategic significance is significant, and the complexity of the recycling process directly restricts the material's efficiency. Regarding organic matter, all types of photovoltaic panels rely heavily on EVA encapsulation materials, but their low toxicity makes environmental risks manageable. Inorganic non-metallic materials such as glass, although having the lowest criticality scores, constitute the largest portion of the recycled material due to their high mass. The key differences between different recycling technologies focus on the balance between material recycling efficiency and carbon emissions. Physical methods demonstrate certain advantages in processing x-Si modules, offering both high recycling efficiency and significant carbon reduction benefits. While pyrolysis provides moderate recycling efficiency, it offers the worst carbon reduction. These technological differences highlight the need to select different processes based on the key characteristics of the materials used in photovoltaic recycling, while simultaneously optimizing the recycling system for high-value materials through technological innovation and policy guidance.

[0115] In practical implementation, when determining a photovoltaic module recycling plan, it is necessary to comprehensively consider the criticality of materials, recycling efficiency, and carbon emission reduction benefits. For x-Si, its high recycling value mainly comes from copper and silicon, while glass and aluminum frames, although accounting for a large proportion, have lower economic efficiency. Therefore, a combination of physical and chemical methods can maximize efficiency: first, aluminum and glass are recovered through mechanical crushing and sorting, then EVA is removed through pyrolysis, and finally silicon is extracted through chemical leaching. The German company Geltz Umwelt-Technologie uses a process of mechanical crushing + pyrolysis + acid leaching to achieve a silicon recovery rate of 92% and a copper recovery rate of 98%. For CdTe, although the supply risks of its core materials tellurium and cadmium are high, market demand is limited, and the toxicity of cadmium means that the recycling process must meet strict environmental standards, making chemical (hydrometallurgical) recycling the preferred method. For example, the American company First Solar uses sulfuric acid-hydrogen peroxide leaching to recover tellurium. In summary, the criticality evaluation method for recycled materials from waste photovoltaic panels provided by this invention breaks through the limitations of traditional single-technology recycling research. It achieves precise assessment of the criticality of different types of photovoltaic panels and recycling technologies through quantitative formulas. In the assessment of metallic materials, it integrates multi-dimensional indicators such as supply risk and economic importance, and introduces parameters such as the World Governance Index to deeply analyze the supply stability of metals in global and domestic markets. For organic materials, it uses weighted calculations based on indices such as potential hazard and toxicity levels to accurately measure their environmental impact, providing a reliable basis for recycling decisions. Simultaneously, it incorporates material recovery rates into the calculation of material benefits and carbon reduction benefits, promoting the coordinated development of resources and the environment by comparing the material benefits and carbon reduction benefits of different recycling technologies. Furthermore, this system, based on data and formulas, ensures the objectivity and reliability of evaluation results, facilitating industry standardization and propelling the waste photovoltaic panel recycling industry towards a new level of standardization and scientific rigor.

[0116] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels, characterized in that, include: Collect information on the raw materials of waste photovoltaic panels, wherein the raw materials include at least one of metals, organic matter and inorganic non-metallic materials; Assess the key indicators of each type of raw material in the waste photovoltaic panels; Determine the production carbon emission factor and recycling carbon emission factor for each type of raw material, and combine the key indicators, recovery rate, production carbon emission factor and recycling carbon emission factor for each type of raw material to determine the material benefits and carbon emission reduction benefits in the recycling process; Based on the above assessment and calculation results, the key differences between different photovoltaic panel types and recycling technologies are analyzed to provide a quantitative basis for the selection of recycling solutions.

2. The material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels according to claim 1, characterized in that, The total key indicators of the metal raw materials are determined by the following formula: t i =CR mi ×m i In the formula, t i CR represents the total critical index of the i-th metal; mi This represents the key indicator for the i-th metal; m i Let i represent the mass of the metal, i be a natural number, and i ≥ 1, representing different types of metal raw materials.

3. The material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels according to claim 2, characterized in that, The comprehensive key indicator CR of the metal m Determined by the following formula: CR m =SR×EI EI=(∑S×GVA) / GVA est ×SI EI ×10 Among them, CR m The overall criticality of a metal is indicated by: SR (Comprehensive Criticality); EI (Supply Risk); S (Economic Importance); GVA (Demand Share of Metal Raw Materials); SI (Market Value of Metals); and WGI (World Governance Index). (HHIWGI) GS The Herfindahl-Hirschman Index (HHIWGI) is a global index based on the World Governance Index. CN This refers to the Herfindahl-Hirschman Index for China, which is based on the World Governance Index.

4. The material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels according to claim 1, characterized in that, The key indicators of the organic matter are determined by the following formula: Among them, CR o For key indicators of organic matter, r1, r2, r3, r4, and r5 represent the potential hazard index, toxicity level index, bioaccumulation index, photochemical reactivity index, and environmental persistence index, respectively; d1, d2, d3, d4, and d5 represent the potential hazard, toxicity level, bioaccumulation, photochemical reactivity, and environmental persistence, respectively; parameter r i The requirements are Wherein: d1, d2, d3, d4, and d5 are 0.37, 0.18, 0.1, 0.2, and 0.15, respectively.

5. The material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels according to claim 1, characterized in that, r i Determined by the following formula: P = 2b1b1′B1 + 4b2B2 AMEG AH 0.107×LD 50 In the formula, P is the potential hazard index value, B1 is the environmental target value for general chemical substances across multiple media, B2 is the environmental target value for hazardous chemical substances across multiple media, and B1, b1′, and B2 are constant terms; if a B2 value can be found, then b1 = 1; if a B2 value cannot be found, then b1 = 2; b1′ = 1.25 is used for the accumulation or chronic toxicity of chemical substances, and b1′ = 1 is only used for acute toxicity; when B1 is found, b2 = 1; when B1 cannot be found, b2 = 1.5; LD 50 This represents the median lethal dose for oral toxicity in rats or imported mice.

6. The material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels according to claim 1, characterized in that, In the inorganic non-metallic materials, the criticality index of glass is 1, the criticality index of air is 0.33, the criticality index of synthetic or processed gases is set at 0.67, and the criticality index of special gases is 1.

7. The material criticality evaluation method for low-carbon recycling technology of waste photovoltaic panels according to claim 1, characterized in that, The material benefits and emission reduction benefits during the recycling process of different types of photovoltaic panels are determined by the following formula: t ri =∑CR mi ×m i ×EOL Rmi +∑CR oi ×m i ×EOL Roi +∑CR ai ×m i ×EOL Rai CE=∑(E vi -E ri )×m i ×EOL Ri In the formula, t ri Indicates the benefits of recycling materials; CR mi Represents the key indicators of the i-th metallic material; CR oi Represents the key indicators of the i-th type of organic material; CR ai The key performance indicator for the i-th material is represented by CE; carbon emission reduction benefit is represented by Evi; carbon emission factor during the production process of the i-th raw material is represented by Eri; and m represents the carbon emission factor during the recycling process of the i-th raw material is represented by Eri. i Let EOL represent the quality of the i-th type of raw material, where i is the raw material, i is a natural number, and i≥1, representing different types of raw materials; Rmi EOL represents the recovery rate of the i-th metal material in the photovoltaic panel recycling process; Roi EOL represents the recovery rate of the i-th organic compound in the photovoltaic panel recycling process; Rai EOL represents the recovery rate of the i-th inorganic non-metallic material in the photovoltaic panel recycling process; Ri This represents the recovery rate of the i-th raw material in the photovoltaic panel recycling process.

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