Photovoltaic module recovery carbon emission reduction potential analysis method based on recovery path

Abstract

The invention provides a photovoltaic module recovered carbon emission reduction potential analysis method based on a recovery path, and the method carries out the quantitative calculation of the carbon revenue and expenditure in the decommissioning and recovery stage of a photovoltaic module through constructing a whole-process evaluation system integrating treatment, recycling and substitution effect. The method comprises the following steps: firstly, distinguishing three recovery paths of a physical method, a heat treatment method and a chemical method, and establishing respective carbon emission accounting models; secondly, respectively establishing recycling emission and native substitution emission reduction models for five recoverable materials, namely aluminum, copper, glass, polycrystalline silicon and silver; and the net carbon emission reduction benefit of component recovery is comprehensively evaluated in combination with landfill emission data of the retired component. According to the method, the difference between the accounting boundary and the path is defined, the defects of an existing method in the aspects of path adaptability, accounting integrity and emission reduction potential prediction are overcome, and decision support can be provided for low-carbon path optimization of the photovoltaic recovery industry.

Description

Technical Field

[0001] This invention belongs to the field of photovoltaics, and specifically relates to a method for analyzing the carbon emission reduction potential of photovoltaic modules based on recycling pathways. Background Technology

[0002] Currently, existing research on carbon emissions and recycling of photovoltaic modules mainly focuses on the manufacturing and power generation stages, lacking a systematic assessment of the carbon reduction benefits of the decommissioning and recycling phases. Existing technologies have several shortcomings: First, they lack comprehensive modeling of multiple recycling pathways, failing to reflect the differences in carbon emissions and reduction capabilities under different technological routes. Second, existing carbon emission accounting methods often only cover the treatment and disposal stages, failing to form a complete accounting system for the entire process of dismantling, transportation, and recycling, and lacking a modular modeling approach, resulting in poor adaptability. Third, current methods generally remain at the static accounting level, making it difficult to respond to dynamic variables such as the growth of photovoltaic module decommissioning, changes in grid factors, and policy interventions, lacking the ability to predict emission reduction potential at the industry scale and in future scenarios. Summary of the Invention

[0003] To address the problems existing in the prior art, the purpose of this invention is to provide a method for analyzing the carbon emission reduction potential of photovoltaic module recycling based on the recycling path. This invention can realize the carbon emission reduction accounting of photovoltaic modules after treatment and reuse through different recycling paths, analyze their carbon emission reduction potential, and provide a methodological basis for the entire end-of-life photovoltaic module recycling industry to carry out carbon emission reduction potential analysis.

[0004] To achieve the above objectives, this application provides the following solution: A method for analyzing the carbon emission reduction potential of photovoltaic modules based on recycling paths includes the following steps: S1: Obtaining carbon emission accounting data for the treatment and disposal stage of scrapped photovoltaic modules; wherein, the carbon emission model for the treatment and disposal stage is classified according to the recycling path, including physical methods, thermal treatment methods, and chemical methods; that is, the carbon emission accounting data for the treatment and disposal stage of scrapped photovoltaic modules includes carbon accounting data for physical treatment and disposal processes, carbon accounting data for thermal treatment and disposal processes, and carbon accounting data for chemical treatment and disposal processes.

[0005] S2: Obtain carbon emission accounting data for the recycling stage of scrapped photovoltaic modules; the carbon emission model for the recycling stage is based on the classification of recycled materials, including recycled aluminum, recycled copper, glass, polysilicon, and silver; that is, the carbon emission accounting data for the recycling stage of scrapped photovoltaic modules includes carbon accounting data for the recycling process of recycled aluminum, recycled copper, glass, polysilicon, and silver.

[0006] S3: Obtain baseline emissions data for primary materials, which include aluminum, copper, glass, polysilicon, and silver; that is, baseline emissions for primary materials refer to the greenhouse gas emissions resulting from the energy consumed in producing aluminum, copper, glass, polysilicon, and silver using primary materials.

[0007] S4: Obtain carbon emission data generated by direct landfilling of decommissioned photovoltaic modules.

[0008] S5: Based on the carbon emission accounting data of the waste photovoltaic module treatment and disposal stage, the carbon emission accounting data of the waste photovoltaic module recycling stage, the baseline emission data of virgin materials, and the carbon emission data generated by the direct landfill of retired photovoltaic modules, the potential for carbon reduction through recycling is calculated.

[0009] This invention establishes a method for analyzing the carbon reduction potential of photovoltaic modules based on recycling pathways, such as... Figure 1 As shown, this invention includes carbon emissions during the disposal phase, carbon emissions during the recycling phase, and a model method for the carbon emission reduction potential of recycling. Through a unified evaluation framework, this invention calculates and compares the carbon emissions and emission reduction benefits of various recycling pathways at each stage. Combined with predicted data from decommissioned components and scenario settings, it outputs the evolution trend of emission reduction potential at an industry scale. This can help governments, enterprises, research institutions, and others identify the optimal recycling pathway, optimize resource allocation, and support the formulation of green policies and the promotion of low-carbon pathways.

[0010] Furthermore, in S1, the carbon emission model for the treatment and disposal stage can be selected from physical methods, thermal treatment methods, and chemical methods. Specifically: The physical method carbon emission accounting model uses mechanical crushing and sorting methods, primarily utilizing energy and consuming no water or other materials. The recovered components mainly consist of aluminum frames, glass, and junction boxes. The carbon emissions from the treatment and disposal process are solely due to the consumption of electricity. The carbon emission accounting model is as follows: CE DI-物理 =AD E ×EF E CE DI-物理 Carbon emissions generated during the physical treatment and disposal of components are expressed in tons of CO2 (tCO2). E The electricity used in the component processing and disposal process, in MWh; EF E The annual average power supply emission factor of the provincial power grid is expressed in units of (tCO2 / MWh).

[0011] The carbon emission accounting model for the thermal treatment method is as follows: This process primarily consumes energy, with no material consumption. Due to the presence of the pyrolysis furnace, the furnace's energy consumption mainly comes from different energy sources, including fossil fuels and electricity. The recovered materials primarily include aluminum frames, junction boxes, and welding strips. During the production process, carbon dioxide emissions occur because EVA is pyrolyzed. The carbon emission accounting model is as follows: CE DI-热法 Carbon emissions generated during the treatment and disposal of components using thermal treatment methods are expressed in tons of CO2 (tCO2). i The activity level data for the i-th fossil fuel is given in tons (t); EF i denoted as , where is the carbon emission factor of the i-th fossil fuel, expressed in tCO2 / t; i represents the type of fossil fuel used in the component's treatment and disposal process; AD E The electricity used in the component processing and disposal process, in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in (tCO2 / MWh); CE P The carbon emissions from plastic pyrolysis during the treatment process are expressed in tCO2.

[0012] The carbon emissions from plastic pyrolysis during thermal processing are shown in the following formula: CE P =N i ×B i ×12 / 44 CE P The carbon emissions from plastic pyrolysis during the treatment process are expressed in tons of CO2 (tCO2); N C The mass of pyrolytic plastics typically includes adhesives such as EVA, measured in tons (t); B i Carbon content in pyrolytic plastics, expressed as a percentage.

[0013] Carbon emission calculation model for chemical methods: Based on the technology of chemical recovery, the process includes mechanical crushing and reagent swelling and dissolution, primarily utilizing energy and separation solvents. The recovered materials mainly consist of aluminum frames, glass, and junction boxes. Carbon emissions from the treatment and disposal process include the consumption of electricity for equipment and the consumption of dissolved and swollen substances. The calculation model is as follows: CE DI-化学 Carbon emissions from the chemical treatment and disposal of components are measured in tons of CO2 (tCO2); M i F represents the amount of material consumed in the i-th method of processing decommissioned photovoltaic modules, in tons (t). iThe carbon emission factor of the i-th main consumed material is expressed in tCO2e / t material; i represents the type of material consumed during the component processing and disposal; AD E The electricity used during component resource utilization is measured in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in (tCO2 / MWh); CE P Carbon emissions during the process, measured in tons of CO2 (tCO2); CE WD Carbon emissions during waste disposal are expressed in tons of CO2 (tCO2).

[0014] In S2, the carbon emission accounting method for the recycling stage selects recycled aluminum, recycled copper, glass, polysilicon, and silver. Specifically: The production process of recycled aluminum typically includes: removal of impurities (such as adhesive strips and coatings); smelting; and aluminum ingot casting and cooling. The formula for calculating the carbon emissions from the recycled aluminum process is as follows: CE RM-再生铝 Carbon emissions during the recycling of recycled aluminum, expressed in tons of CO2 (tCO2); AD i The activity level data for the i-th fossil fuel is given in tons (t); EF i AD represents the carbon emission factor of the i-th fossil fuel, expressed in tCO2 / t; i represents the type of fossil fuel used in the recycling process; E The electricity used in the recycling process, measured in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in tCO2 / MWh; CE WD Carbon emissions during the waste disposal process in the recycling stage are expressed in tCO2.

[0015] Accordingly, in S3, the formula for calculating the baseline carbon emissions of primary aluminum materials of equal mass is: CE Su b st-再生铝 =M 再生铝 ×EF 原生铝 M 再生铝 The mass of aluminum recovered is expressed in tons (t); EF 原生铝 This represents the carbon emission factor during the primary production process of aluminum, expressed in tCO2e / t aluminum.

[0016] The processing of recycled copper mainly includes: impurity removal and pretreatment (such as removing the insulating layer); smelting and refining (pyrometallurgical or hydrometallurgical processes); and casting copper ingots or copper wires for further processing. The formula for calculating the process carbon emissions of recycled copper is as follows: CE RM-再生铜Carbon emissions during the recycling of recycled aluminum, expressed in tons of CO2 (tCO2); AD i The activity level data for the i-th fossil fuel is given in tons (t); EF i AD represents the carbon emission factor of the i-th fossil fuel, expressed in tCO2 / t; i represents the type of fossil fuel used in the recycling process; E The electricity used in the recycling process, measured in MWhεEF E The annual average power supply emission factor of the provincial power grid, expressed in tCO2 / MWh; CE WD Carbon emissions during the waste disposal process in the recycling stage are expressed in tCO2.

[0017] Accordingly, in S3, the formula for calculating the baseline carbon emissions of primary copper materials of equal mass is: CE Subst-再生铜 =M 再生钢 ×EF 原生钢 M 再生铜 The mass of copper recovered is expressed in tons (t); EF 原生铜 This represents the carbon emission factor during the primary production process of copper, expressed in tCO2e / t copper.

[0018] Carbon emission accounting for glass recycling: When using physical methods and other processes for recycling, some components can retain large, intact pieces of glass with clean surfaces and intact structures, making them suitable for direct reuse. This type of glass is often used in architectural glass, remanufactured mirrors, or non-structural materials, eliminating the need for high-temperature remelting. Its carbon emissions mainly come from cleaning, cutting, and transportation processes, which have relatively low energy consumption and can be ignored in terms of process carbon emissions.

[0019] In recycling processes such as heat treatment, glass is typically crushed into granules and can only be used as raw material in glass reprocessing systems. This process requires high-temperature melting (usually around 1400℃) to reprocess it into flat glass or other industrial glass products. Its energy consumption is mainly concentrated in furnace operation, and its carbon emission intensity is significantly higher than that of whole glass recycling. The formula for calculating the process carbon emissions of broken glass recycling is: CE RM-玻璃 Carbon emissions during glass recycling, expressed in tons of CO2 (tCO2); AD i The activity level data for the i-th fossil fuel is given in tons (t); EF i AD represents the carbon emission factor of the i-th fossil fuel, expressed in tCO2 / t; i represents the type of fossil fuel used in the recycling process; E The electricity used in the recycling process, measured in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in tCO2 / MWh; CE WDCarbon emissions during the waste disposal process in the recycling stage are expressed in tCO2.

[0020] Accordingly, in S3, the formula for calculating the baseline carbon emissions of virgin glass material of equal mass is: CE Subst-玻璃 =M 玻璃 ×EF 平板玻璃 M 玻璃 The total mass of recycled glass, in tons (t); EF 平安玻璃 This represents the carbon emission factor during the production of flat glass, expressed in t CO2e / t glass.

[0021] In the process of recycling polycrystalline silicon and silver, the solar cells are pretreated and repeatedly acid-leached to obtain elemental silicon and silver nitrate solution, and then elemental silver can be obtained through reduction.

[0022] The formula for calculating the carbon emissions from the recycling process of polysilicon is as follows: CE RM-多晶硅 Carbon emissions during the recycling of polysilicon, expressed in tons of CO2 (tCO2); M i F represents the material consumption of the i-th type of battery cell, in tons (t). i The carbon emission factor of the i-th main consumed material is expressed in tCO2e / t material; i represents the type of material consumed during the component processing and disposal; AD E The electricity used in the polysilicon recycling process is expressed in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in (tCO2 / MWh); CE p Carbon emissions during the process, measured in tons of CO2 (tCO2); CE WD Carbon emissions during waste disposal are expressed in tons of CO2 (tCO2); m 多晶硅 This refers to the proportion of polycrystalline silicon mass to the total mass of the solar cells.

[0023] Accordingly, in S3, the formula for calculating the baseline carbon emissions of high-purity polycrystalline silicon materials of equal quality is: CE Subst-多晶硅 =M 多晶硅 ×EF 高纯多晶硅 M 多晶硅 The total recovered mass of polysilicon is expressed in tons (t); EF 高纯多晶硅 This represents the carbon emission factor during the production of high-purity polysilicon, expressed in tCO2e / tpolysilicon.

[0024] The formula for calculating the carbon emissions from the recycling process of silver is as follows: CE RM-银 Carbon emissions during silver recycling are expressed in tons of CO2 (tCO2); M i F represents the material consumption of the i-th type of battery cell, in tons (t). i The carbon emission factor of the i-th main consumed material is expressed in tCO2e / t material; i represents the type of material consumed during the component processing and disposal; AD E The electricity used in the silver recycling process is expressed in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in (tCO2 / MWh); CE P Carbon emissions during the process, measured in tons of CO2 (tCO2); CE WD Carbon emissions during waste disposal are expressed in tons of CO2 (tCO2); m 银 This refers to the proportion of elemental silver mass to the total mass of the solar cell.

[0025] Accordingly, in S3, the formula for calculating the baseline carbon emissions of elemental silver materials of equal mass is: CE Subst-银 =M 银 ×EF 年质银 M 银 The total recovered mass of silver, in tons (t); EF 单质银 This represents the carbon emission factor of elemental silver during the production process, expressed in tCO2e / tsilver.

[0026] In S4, carbon emission data for retired photovoltaic modules directly landfilled is obtained. When photovoltaic modules are sent directly to landfills due to inadequate recycling systems or high processing costs, this process inevitably generates certain carbon emissions, mainly including carbon emissions from landfill operations and carbon emissions released during material degradation.

[0027] Furthermore, the carbon emission reduction potential of photovoltaic module recycling includes three parts: carbon emissions from the photovoltaic module recycling process, carbon emissions indirectly offsetting the primary carbon emissions of the recycled materials, and carbon emission reductions generated by shifting photovoltaic modules from direct landfill to recycling. Among them, carbon emissions from the photovoltaic module recycling process include two processes: module processing and disposal, and recycling.

[0028] Therefore, the formula for calculating the carbon emission reduction potential of photovoltaic modules is: E = CE DI +CE RM -CE Subst -CE LF Among them, CE DI This refers to the carbon emissions generated during the recycling of photovoltaic modules, encompassing three different recycling pathways: physical methods, thermal treatment methods, and chemical methods; CERM This indicates carbon emissions generated during the recycling phase, encompassing five main recyclable materials: aluminum, copper, glass, polysilicon, and silver; CE Subst This indicates that the recycling of recycled materials indirectly offsets the primary carbon emissions of those materials; CE LF This refers to the carbon emissions generated by directly landfilling photovoltaic modules.

[0029] The advantages of this invention compared to the prior art are as follows: (1) Based on different recycling paths, regeneration paths, and virgin material manufacturing accounting data for waste photovoltaic modules, this invention first calculates the project's emissions based on the recycling and regeneration paths, then calculates the baseline emissions of the materials based on the virgin material manufacturing accounting data, and the carbon emissions from direct landfilling of waste photovoltaic modules. Finally, based on the baseline emissions, landfill carbon emissions, and project emissions, the emission reduction can be calculated. This invention targets waste photovoltaic modules, conducting carbon emission reduction accounting based on different recycling paths. It uses the virgin paths of different recycled materials and the carbon emission method of this project as a benchmark, while also considering the hidden carbon emissions from direct landfilling of materials. From a full life cycle perspective, the final accounting result is closer to the actual carbon emission situation, ensuring the accuracy of carbon emission reduction through the recycling of waste modules, achieving precise accounting for carbon emission reduction of waste photovoltaic modules, and providing a methodological basis for carbon emission reduction accounting work in the waste photovoltaic industry. Attached Figure Description

[0030] Figure 1 This is a flowchart illustrating a method for analyzing the carbon emission reduction potential of photovoltaic modules based on recycling paths, as provided in Embodiment 1 of the present invention. Figure 2 A process flow diagram for the treatment and disposal stage in the analysis method of carbon emission reduction potential of photovoltaic modules; Figure 3 This is a process flow diagram of the recycling stage in the method for analyzing the carbon emission reduction potential of photovoltaic modules. Detailed Implementation

[0031] To better understand the purpose, technical solution, and advantages of this application, the application is described and explained below in conjunction with the accompanying drawings and embodiments.

[0032] Example 1 This embodiment selects the thermal treatment method for recycling as an evaluation case to assess the carbon emission potential of photovoltaic module recycling, referring to... Figure 1 As shown, the specific steps include: Step S1: Determine the system boundary for analyzing the carbon reduction potential of photovoltaic modules.

[0033] The system boundaries include carbon emission accounting for the disposal and treatment of end-of-life photovoltaic (PV) modules, carbon emission accounting for the recycling and reuse of end-of-life PV modules, baseline emissions from virgin materials, and carbon emissions from direct landfilling of decommissioned PV modules. In this embodiment, carbon emission accounting for the disposal and treatment of end-of-life PV modules refers to carbon accounting data for the thermal treatment process; carbon emission accounting data for the recycling and reuse of end-of-life PV modules includes carbon accounting data for the recycling and reuse of recycled aluminum, recycled copper, recycled glass, recycled polysilicon, and recycled silver; baseline emissions data for virgin materials, where virgin materials include aluminum, copper, glass, polysilicon, and silver.

[0034] Step S2: Obtain data from the photovoltaic module recycling carbon reduction potential analysis model, including carbon emission accounting data during the treatment and disposal stage. Figure 2 Carbon emission accounting data during the recycling stage ( Figure 3 ), baseline emissions data for virgin materials and carbon emissions data from direct landfill.

[0035] In this embodiment, the carbon emissions in each part are obtained through methods such as installing data collection equipment, reading from public databases, investigating work logs and reports, and conducting on-site surveys.

[0036] The heat treatment process involves removing the junction box and aluminum frame, performing heat treatment on the back panel, using a corresponding pyrolysis waste gas treatment device, recovering the complete glass, copper wires, and solar cells from the laminate, and carrying out a hydrometallurgical recycling process for polycrystalline silicon and silver in the solar cells.

[0037] For example, the relevant data that need to be analyzed and statistically analyzed in the heat treatment process include: the types and amounts of materials used and consumed during the treatment, the types and amounts of energy used and consumed during the treatment, the carbon emission factors of various energy sources, and the quality and carbon content of plastics in photovoltaic modules.

[0038] Furthermore, to refine the calculation method for carbon emissions generated by the thermal treatment method, the following formula for calculating carbon emissions generated by the treatment module is summarized in this embodiment: CE DI-热法 Carbon emissions generated during the treatment and disposal of components using thermal treatment methods are expressed in tons of CO2 (tCO2). i The activity level data for the i-th fossil fuel is given in tons (t); EF i denoted as , where is the carbon emission factor of the i-th fossil fuel, expressed in tCO2 / t; i represents the type of fossil fuel used in the component's treatment and disposal process; AD EThe electricity used in the component processing and disposal process, in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in (tCO2 / MWh); CE P The carbon emissions from plastic pyrolysis during the treatment process are expressed in tCO2.

[0039] The carbon emissions from plastic pyrolysis during further thermal treatment are shown in the following formula: CE P =N i ×B i ×12 / 44 CE P The carbon emissions from plastic pyrolysis during the treatment process are expressed in tons of CO2 (tCO2); N C The mass of pyrolytic plastics typically includes adhesives such as EVA, measured in tons (t); B i Carbon content in pyrolytic plastics, expressed as a percentage.

[0040] Furthermore, the relevant data that needs to be analyzed and statistically analyzed for the heat treatment recycling method include: the types and amounts of materials used and consumed during recycling, the types and amounts of energy used and consumed during recycling, and the carbon emission factors of various energy sources.

[0041] Further recycled aluminum production processes typically include: impurity removal (such as adhesive strips and coatings); smelting; and aluminum ingot casting and cooling. The formula for calculating the process carbon emissions of recycled aluminum is: CE RM-再生铝 Carbon emissions during the recycling of recycled aluminum, expressed in tons of CO2 (tCO2); AD i The activity level data for the i-th fossil fuel is given in tons (t); EF i AD represents the carbon emission factor of the i-th fossil fuel, expressed in tCO2 / t; i represents the type of fossil fuel used in the recycling process; E The electricity used in the recycling process, measured in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in tCO2 / MWh; CE WD Carbon emissions during the waste disposal process in the recycling stage are expressed in tCO2.

[0042] The formula for calculating the carbon emissions of a baseline of equivalent mass of primary aluminum materials is as follows: CE Subst-再生铝 =M 再生铝 ×EF 原生铝 M 再生铝 The mass of aluminum recovered is expressed in tons (t); EF 原生铝This represents the carbon emission factor during the primary production process of aluminum, expressed in tCO2e / t aluminum.

[0043] Further processing of recycled copper mainly includes: impurity removal and pretreatment (such as removing the insulating layer); smelting and refining (pyrometallurgical or hydrometallurgical processes); and reprocessing of cast copper ingots or copper wires. The formula for calculating the process carbon emissions of recycled copper is as follows: CE RM-再生铜 Carbon emissions during the recycling of recycled aluminum, expressed in tons of CO2 (tCO2); AD i The activity level data for the i-th fossil fuel is given in tons (t); EF i AD represents the carbon emission factor of the i-th fossil fuel, expressed in tCO2 / t; i represents the type of fossil fuel used in the recycling process; E The electricity used in the recycling process, measured in MWh; EF E The annual average power supply emission factor of the provincial power grid, in units of tCO2 / MWhεCE WD Carbon emissions during the waste disposal process in the recycling stage are expressed in tCO2.

[0044] The formula for calculating the carbon emissions of a baseline of equivalent mass of primary copper materials is as follows: CE Subst-再生铜 =M 再生铜 ×EF 原生铜 M 再生铜 The mass of copper recovered is expressed in tons (t); EF 原生铜 This represents the carbon emission factor during the primary production process of copper, expressed in tCO2e / t copper.

[0045] Further carbon emission accounting for glass recycling reveals that in processes such as heat treatment, glass is typically crushed into granules and can only be used as raw material in the glass reprocessing system. This process requires high-temperature melting (usually around 1400℃) to reprocess it into flat glass or other industrial glass products. Its energy consumption is mainly concentrated in furnace operation, and its carbon emission intensity is significantly higher than that of whole glass recycling. The formula for calculating the process carbon emissions of broken glass recycling is as follows: CE RM-玻璃 Carbon emissions during glass recycling, expressed in tons of CO2 (tCO2); AD i The activity level data for the i-th fossil fuel is given in tons (t); EF i AD represents the carbon emission factor of the i-th fossil fuel, expressed in tCO2 / t; i represents the type of fossil fuel used in the recycling process; E The electricity used in the recycling process, measured in MWh; EFE The annual average power supply emission factor of the provincial power grid, expressed in tCO2 / MWh; CE WD Carbon emissions during the waste disposal process in the recycling stage are expressed in tCO2.

[0046] The formula for calculating the carbon emissions of a baseline of equivalent quality virgin glass material is as follows: CE Subst-玻璃 =M 玻璃 ×EF 平板玻璃 M 玻璃 The total mass of recycled glass, in tons (t); EF 平安玻璃 This represents the carbon emission factor during the production of flat glass, expressed in tCO2e / t glass.

[0047] In the further recycling of polycrystalline silicon and silver, the solar cells are pretreated and subjected to multiple acid leaching processes to obtain elemental silicon and silver nitrate solution, which can then be reduced to obtain elemental silver.

[0048] The formula for calculating the carbon emissions from the recycling process of polysilicon is as follows: CE RM-多晶硅 Carbon emissions during the recycling of polysilicon, expressed in tons of CO2 (tCO2); M i F represents the material consumption of the i-th type of battery cell, in tons (t). i The carbon emission factor of the i-th main consumed material is expressed in tCO2e / t material; i represents the type of material consumed during the component processing and disposal; AD E The electricity used in the polysilicon recycling process is expressed in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in (tCO2 / MWh); CE P Carbon emissions during the process, measured in tons of CO2 (tCO2); CE WD Carbon emissions during waste disposal are expressed in tons of CO2 (tCO2); m 多晶硅 This refers to the proportion of polycrystalline silicon mass to the total mass of the solar cells.

[0049] The formula for calculating the baseline carbon emissions of high-purity polycrystalline silicon materials of equivalent quality is as follows: CE Subst-多晶硅 =M 多晶硅 ×EF 高纯多晶硅 M 多晶硅 The total recovered mass of polysilicon is expressed in tons (t); EF 高纯多晶硅 This represents the carbon emission factor during the production of high-purity polysilicon, expressed in tCO2e / t polysilicon.

[0050] The formula for calculating the carbon emissions from the recycling process of silver is as follows: CE RM-银 Carbon emissions during silver recycling are expressed in tons of CO2 (tCO2); M i F represents the material consumption of the i-th type of battery cell, in tons (t). i The carbon emission factor of the i-th main consumed material is expressed in tCO2e / t material; i represents the type of material consumed during the component processing and disposal; AD E The electricity used in the silver recycling process is expressed in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in (tCO2 / MWh); CE P Carbon emissions during the process, measured in tons of CO2 (tCO2); CE WD Carbon emissions during waste disposal are expressed in tons of CO2 (tCO2); m 银 This refers to the proportion of elemental silver mass to the total mass of the solar cell.

[0051] The formula for calculating the carbon emissions of a baseline of equivalent mass of elemental silver is as follows: CE Subst-银 =M 银 ×EF 单银银 M 银 The total recovered mass of silver, in tons (t); EF 单质银 This represents the carbon emission factor of elemental silver during the production process, expressed in tCO2e / tsilver.

[0052] Further data on carbon emissions from the direct landfilling of decommissioned photovoltaic modules is needed. When photovoltaic modules are sent directly to landfills due to inadequate recycling systems or high processing costs, this process inevitably generates carbon emissions, primarily from landfill operations and material degradation.

[0053] Step S3: Based on the data, calculate the potential model for carbon recycling and emission reduction.

[0054] For example, the formula for calculating the carbon emission reduction potential of photovoltaic modules through heat treatment is as follows: E = CE DI +CE RM -CE Subst -CE LF Where E represents the carbon reduction potential of photovoltaic modules through thermal treatment; CE DI This indicates that the carbon emissions generated during the heat treatment process of photovoltaic modules are being handled; CE RMThis indicates carbon emissions generated during the recycling phase, encompassing five main recyclable materials: aluminum, copper, glass, polysilicon, and silver; CE Subst This indicates that the recycling of recycled materials indirectly offsets the primary carbon emissions of those materials; CE LF This refers to the carbon emissions generated by directly landfilling photovoltaic modules.

[0055] Example 2 This embodiment uses the thermal treatment recycling method as an evaluation case to analyze the carbon emission reduction potential of the recycling process of scrapped photovoltaic modules. The following calculation and analysis are based on 50 tons of scrapped photovoltaic modules. The specific calculation steps are as follows: In this embodiment, the data required for the photovoltaic module recycling carbon reduction potential analysis model includes: carbon emission accounting data during the thermal treatment disposal stage, carbon emission accounting data during the recycling stage, baseline emission data of virgin materials, and carbon emission data generated by direct landfill.

[0056] For example, the relevant data that needs to be analyzed and statistically analyzed in the heat treatment process include: the types and quantities of materials used and consumed during the treatment, the types and quantities of energy used and consumed during the treatment, the carbon emission factors of various energy sources, and the mass and carbon content of the plastics in the photovoltaic modules. In this embodiment, it is assumed that only electricity and natural gas are consumed in the treatment stage.

[0057] The relevant data that needs to be analyzed and statistically analyzed for the recycling portion of the heat treatment method includes: the types and quantities of materials used and consumed during recycling, the types and quantities of energy used and consumed during recycling, and the carbon emission factors of various energy sources. The heat treatment method requires the recycling of waste aluminum, waste copper, broken glass, and waste battery cells. In this embodiment, the carbon footprints of existing recycled aluminum, recycled copper, flat glass, metallurgical silicon, and recycled silver products are used to replace the carbon emissions from their recycling process.

[0058] Data on baseline carbon emissions for materials of equivalent quality. This primarily includes baseline carbon emissions for primary aluminum, primary copper, flat glass, metallurgical silicon, and primary silver.

[0059] Carbon emissions from the direct landfilling of decommissioned photovoltaic modules. When photovoltaic modules are sent directly to landfills due to inadequate recycling systems or high processing costs, this process inevitably generates carbon emissions, primarily from landfill operations and the release of carbon from material degradation.

[0060] Table 1: Detailed Indicators and Values ​​for Component Recovery via Heat Treatment Table 2: Analysis of the carbon emission reduction potential of photovoltaic modules based on heat treatment method part Carbon emission accounting <![CDATA[Treatment and Disposal of CE DI > 21.389 <![CDATA[Recycling CE RM > 25.916 <![CDATA[Baseline carbon emissions CE Subst > 149.526 <![CDATA[Direct landfill CE LF > 11 Carbon emission reduction potential E -113.221 As shown in Table 1-2, referring to step S3, the carbon emission reduction potential E of 50t of scrapped photovoltaic modules is -113.221t, and the average carbon emission reduction potential E per ton of scrapped photovoltaic modules is... 均 It is -2.26442t.

Claims

1. A method for analyzing the carbon emission reduction potential of photovoltaic modules based on recycling pathways, characterized in that: include: S1: Obtain carbon emission accounting data for the processing and disposal of scrapped photovoltaic modules, including carbon accounting data for physical processing, thermal processing, and chemical processing. S2: Obtain carbon emission accounting data for the recycling stage of scrapped photovoltaic modules, including carbon accounting data for recycled aluminum, recycled copper, recycled glass, recycled polysilicon, and recycled silver. S3: Obtain baseline emissions data for virgin materials, including greenhouse gas emissions from the energy consumed in producing aluminum, copper, glass, polysilicon, and silver using virgin materials; S4: Obtain carbon emission data from the direct landfilling of decommissioned photovoltaic modules; S5: Based on the data obtained from S1-S4, calculate the potential for carbon reduction through recycling.

2. The method according to claim 1, characterized in that: In S1, the calculation model for obtaining carbon accounting data from the physical treatment and disposal process is as follows: WHAT DI-物理 =AD E ×EF E CE DI-物理 Carbon emissions generated during the physical treatment and disposal process are expressed in tons of CO2 (tCO2). E The electricity used in the component processing and disposal process, in MWh; EF E The annual average power supply emission factor of the provincial power grid is expressed in tCO2 / MWh.

3. The method according to claim 1, characterized in that: In S1, the calculation model for obtaining carbon accounting data from the thermal treatment process is as follows: CE DI-热法 Carbon emissions generated during the treatment and disposal process using thermal treatment methods are expressed in tons of CO2 (tCO2). i The activity level data for the i-th fossil fuel is given in tons (t); EF i denoted as , where is the carbon emission factor of the i-th fossil fuel, expressed in tCO2 / t; i represents the type of fossil fuel used in the component's treatment and disposal process; AD E The electricity used in the component processing and disposal process, in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in tCO2 / MWh; CE P The carbon emissions from plastic pyrolysis during the treatment process are expressed in tCO2. WHAT P =N i ×B i ×12 / 44 N i The mass of the pyrolytic plastic entering the process is expressed in tons (t); B i The carbon content in pyrolytic plastics is expressed as a percentage.

4. The method according to claim 1, characterized in that: In S1, the accounting model for obtaining carbon accounting data from the chemical treatment and disposal process is as follows: CE DI-化学 Carbon emissions from the chemical treatment and disposal of components are measured in tons of CO2 (tCO2); M i F represents the amount of material consumed in the i-th method of processing decommissioned photovoltaic modules, in tons (t). i , where is the carbon emission factor of the i-th major consumed material, expressed in tCO2e / t material; i represents the type of material consumed during the component processing and disposal; AD E The electricity used during component resource utilization is measured in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in tCO2 / MWh; CE P Carbon emissions during the process, measured in tons of CO2 (tCO2); CE WD Carbon emissions during waste disposal are expressed in tons of CO2 (tCO2).

5. The method according to claim 1, characterized in that: In S2, the formula for calculating carbon accounting data in the recycled aluminum recycling process is as follows: CE RM-再生铝 Carbon emissions during the recycling of recycled aluminum, expressed in tons of CO2 (tCO2); AD i The activity level data for the i-th fossil fuel is given in tons (t); EF i AD represents the carbon emission factor of the i-th fossil fuel, expressed in tCO2 / t; i represents the type of fossil fuel used in the recycling process; E The electricity used in the recycling process, measured in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in tCO2 / MWh; CE WD Carbon emissions during waste disposal in the recycling phase are expressed in tCO2. In S3, the formula for calculating the baseline carbon emissions of primary aluminum materials of equal mass is: WHAT Subst-再生铝 =M 再生铝 ×EF 原生铝 M 再生铝 The mass of aluminum recovered is expressed in tons (t); EF 原生铝 This represents the carbon emission factor during the primary production process of aluminum, expressed in tCO2e / t aluminum.

6. The method according to claim 1, characterized in that: In S2, the formula for calculating carbon accounting data in the recycled copper recycling process is: CE RM-再生铜 Carbon emissions during the recycling of recycled aluminum, expressed in tons of CO2 (tCO2); AD i The activity level data for the i-th fossil fuel is given in tons (t); EF i AD represents the carbon emission factor of the i-th fossil fuel, expressed in tCO2 / t; i represents the type of fossil fuel used in the recycling process; E The electricity used in the recycling process, measured in MWhcEF. E The annual average power supply emission factor of the provincial power grid, expressed in tCO2 / MWh; CE WD Carbon emissions during waste disposal in the recycling phase are expressed in tCO2. In S3, the formula for calculating the baseline carbon emissions of primary copper materials of equal mass is: WHAT Subst-再生铜 =M 再生铜 ×EF 原生铜 M 再生铜 The mass of copper recovered is expressed in tons (t); EF 原生铜 This represents the carbon emission factor during the primary production process of copper, expressed in tCO2e / t copper.

7. The method according to claim 1, characterized in that: In S2, the formula for calculating carbon accounting data in the glass recycling process is: CE RM-玻璃 Carbon emissions during glass recycling, expressed in tons of CO2 (tCO2); AD i The activity level data for the i-th fossil fuel is given in tons (t); EF i AD represents the carbon emission factor of the i-th fossil fuel, expressed in tCO2 / t; i represents the type of fossil fuel used in the recycling process; E The electricity used in the recycling process, measured in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in tCO2 / MWh; CE WD Carbon emissions during waste disposal in the recycling phase are expressed in tCO2. In S3, the formula for calculating the baseline carbon emissions of virgin glass material of equal mass is: WHAT Subst-玻璃 =M 玻璃 ×EF 平板玻璃 M 玻璃 The total mass of recycled glass, in tons (t); EF 平安玻璃 This represents the carbon emission factor during the production of flat glass, expressed in t CO2e / t glass.

8. The method according to claim 1, characterized in that: In S2, the formula for calculating carbon accounting data in the polysilicon recycling process is: CE RM-多晶硅 Carbon emissions during the recycling of polysilicon, expressed in tons of CO2 (tCO2); M i F represents the material consumption of the i-th type of battery cell, in tons (t). i The carbon emission factor of the i-th main consumed material is expressed in tCO2e / t material; i represents the type of material consumed during the component processing and disposal; AD E The electricity used in the polysilicon recycling process is expressed in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in (tCO2 / MWh); CE P Carbon emissions during the process, measured in tons of CO2 (tCO2); CE WD Carbon emissions during waste disposal are expressed in tons of CO2 (tCO2); m 多晶硅 The proportion of polycrystalline silicon mass to the total mass of the solar cells; In S3, the formula for calculating the baseline carbon emissions of high-purity polycrystalline silicon materials of equal quality is: WHAT Subst-多晶硅 =M 多晶硅 ×EF 高纯多晶硅 M 多晶硅 The total recovered mass of polysilicon is expressed in tons (t); EF 高纯多晶硅 This represents the carbon emission factor during the production of high-purity polysilicon, expressed in tCO2e / tpolysilicon.

9. The method according to claim 1, characterized in that: In S2, the formula for calculating carbon accounting data in the silver recycling process is: CE RM-银 Carbon emissions during silver recycling are expressed in tons of CO2 (tCO2); M i F represents the material consumption of the i-th type of battery cell, in tons (t). i The carbon emission factor of the i-th main consumed material is expressed in tCO2e / t material; i represents the type of material consumed during the component processing and disposal; AD E The electricity used in the silver recycling process is expressed in MWh; EF E The annual average power supply emission factor of the provincial power grid, expressed in tCO2 / MWh; CE P Carbon emissions during the process, tCO2; CE WD Carbon emissions during waste disposal are expressed in tons of CO2 (tCO2); m 银 The proportion of elemental silver to the total mass of the solar cell; In S3, the formula for calculating the baseline carbon emissions of elemental silver of equal mass is: WHAT Subst-银 =M 银 ×EF 单质银 M 银 The total recovered mass of silver, in tons (t); EF 单质银 This represents the carbon emission factor of elemental silver during the production process, expressed in tCO2e / tsilver.

10. The method according to claim 1, characterized in that: In S4, the formula for calculating carbon emission data generated by direct landfilling of decommissioned photovoltaic modules is as follows: E=CE DI +CE RM -WHAT Subst -WHAT LF WHAT DI =EC DI-物理 +CE DI-热法 +CE DI-化学 ; WHAT RM =EC RM-再生铝 +CE RM-再生铜 +CE RM-玻璃 +CE RM-多晶硅 +CE RM-银 ; WHAT Subst =EC Subst-再生铝 +CE Subst-再生铜 +CE Subst-再生玻璃 +CE Subst-再生多晶硅 +CE Subst-再生银 ; CE LF This refers to the carbon emissions generated by directly landfilling photovoltaic modules.

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