Single-double glass decommissioned photovoltaic module integrated pyrolysis device and method

Abstract

The application discloses a single-double-glass decommissioned photovoltaic module integrated pyrolysis device and method, and relates to the field of photovoltaic module recycling.The pyrolysis device comprises an automatic feeding system, a module identification system, a tunnel-type pyrolysis furnace, a gas delivery pump and a control unit.The tunnel-type pyrolysis furnace comprises a natural gas heated preheating section and an electrically heated pyrolysis section.The two ends of the tunnel-type pyrolysis furnace are open and connected with dynamic sealing structures.The pyrolysis gas generated by the tunnel-type pyrolysis furnace is collected and combusted with natural gas to provide heat for the preheating section.The control unit automatically sets the pyrolysis temperature according to the identification result and automatically adjusts the recycling ratio according to the pyrolysis gas concentration and the preheating section temperature.The application solves the technical problem of unorganized discharge of pyrolysis gas in the prior art through the dynamic sealing structure and the micro-negative pressure pyrolysis cavity.Meanwhile, the single-glass photovoltaic module and the double-glass photovoltaic module are efficiently and compatibly processed through batch precise temperature control, and the application has the advantages of high automation, environmental protection and energy saving.

Description

Technical Field

[0001] This application belongs to the field of recycling and processing technology of decommissioned photovoltaic modules, specifically relating to an integrated pyrolysis device and method for single and double glass decommissioned photovoltaic modules. Background Technology

[0002] With the rapid development of the photovoltaic industry, the environmentally friendly recycling and disposal of retired photovoltaic modules has become an urgent technical challenge. Retired photovoltaic modules mainly include outer aluminum frames, laminated photovoltaic modules, and junction boxes. Laminated photovoltaic modules are further divided into single-glass and double-glass photovoltaic modules. Single-glass photovoltaic modules consist of adhesive backing (mainly polyvinyl fluoride PVF), EVA, solar cells, busbars, and glass, while double-glass photovoltaic modules consist of glass, solar cells, and EVA.

[0003] Pyrolysis is used to process laminated optoelectronic components, effectively removing organic encapsulation materials such as EVA and adhesive, and achieving efficient dissociation and recycling of glass, silicon wafers, and metal wires. However, existing pyrolysis equipment has the following technical problems: (1) Unorganized emission of pyrolysis gas: Most existing tunnel pyrolysis devices have an open structure at both ends. During the pyrolysis process, especially when processing single-glass photovoltaic modules, a large amount of fluorine-containing organic gas will be generated and emitted along both ends of the furnace body, causing serious pollution and environmental risks at the work site. (2) Single-glass photovoltaic modules and double-glass photovoltaic modules are difficult to process in the same pyrolysis conditions: Double-glass photovoltaic modules contain only EVA organic layer, and the amount of pyrolysis gas generated is small and the rate is slow. Existing two-stage open tunnel furnaces can still be used with difficulty; however, single-glass photovoltaic modules contain polyvinyl fluoride backing layer, and the organic carbon chain is long. Pyrolysis requires higher temperature and more precise temperature control, and a large amount of high-flow-rate fluorine-containing pyrolysis gas will be generated. Existing open equipment cannot effectively seal and control the temperature, resulting in incomplete pyrolysis, difficulty in separating glass from silicon wafers, and serious leakage of fluorine-containing tail gas. Therefore, they are difficult to process in a compatible manner. Summary of the Invention

[0004] The present invention aims to provide an integrated pyrolysis device and method for decommissioned single and double glass photovoltaic modules based on the coordinated supply of pyrolysis gas and heat source, in order to solve the technical problems existing in the above-mentioned open tunnel furnace.

[0005] To achieve the above objectives, the present invention provides an integrated pyrolysis device for single and double-glass decommissioned photovoltaic modules, comprising: Automatic feeding system: used for automatic feeding of single and double glass decommissioned photovoltaic modules, removal of junction boxes, and disassembly of aluminum frames; Component identification system: It is installed in the automatic feeding system and is used to identify the type of single- or double-glass decommissioned photovoltaic modules; Tunnel-type pyrolysis furnace: It is connected to the output end of the automatic feeding system. The tunnel-type pyrolysis furnace is divided into a preheating section and a pyrolysis section along the material conveying direction. The preheating section is equipped with a natural gas heating device for heating the preheating section, and the pyrolysis section is equipped with an electric heating device for controlling the temperature of the pyrolysis section. The two ends of the tunnel-type pyrolysis furnace are open and connected with a dynamic sealing structure. Gas transfer pump: used to collect pyrolysis gas produced by the tunnel pyrolysis furnace. The inlet end of the gas transfer pump is connected to the pyrolysis gas outlet of the tunnel pyrolysis furnace, and the outlet end of the gas transfer pump is connected to the natural gas heating device. It is used to co-combust the collected pyrolysis gas with external natural gas to provide heat for the preheating section. The cooling discharge system is connected to the output end of the tunnel pyrolysis furnace and is used to cool the pyrolyzed material to a set temperature before discharging it. Control unit: It is connected to the automatic feeding system, component identification system, natural gas heating device, electric heating device, gas delivery pump and cooling discharge system respectively.

[0006] This pyrolysis device integrates automatic feeding, component identification, tunnel pyrolysis furnace, gas delivery pump, cooling discharge system and control unit into a single system, realizing fully automatic, sealed and energy-saving pyrolysis of single-glass photovoltaic modules and double-glass photovoltaic modules in the same pyrolysis furnace. It solves the dual technical problems of incompatible processing of the two types of photovoltaic modules and fugitive emission of pyrolysis gas in the existing technology.

[0007] Preferably, the outlet end of the gas delivery pump is connected to a burner coupling interface, and the gas delivery pump is connected to the natural gas heating device through the burner coupling interface. By setting the burner coupling interface, stable co-combustion of pyrolysis gas and natural gas is achieved.

[0008] Preferably, the system further includes a purification system and a gas storage tank connected in series. The inlet of the purification system is connected to the outlet of the tunnel pyrolysis furnace to purify the pyrolysis gas discharged from the furnace. The inlet of the gas storage tank is connected to the outlet of the purification system to store the purified pyrolysis gas. A control unit is connected to the gas storage tank to adjust the reuse ratio of the pyrolysis gas in the tank according to the concentration of the gas in the tank and the heating load of the tunnel pyrolysis furnace. By setting up the purification system and the gas storage tank, combined with the control unit, the buffer storage and automatic adjustment of the reuse ratio of the pyrolysis gas are achieved, effectively reducing the consumption of external natural gas.

[0009] Preferably, the control unit adjusts the reuse ratio of pyrolysis gas in the storage tank as follows: when the concentration of organic components in the pyrolysis gas in the storage tank is below 8%, the reuse of pyrolysis gas in the storage tank is shut off; when the concentration of organic components in the pyrolysis gas in the storage tank is between 8% and 20%, the control unit dynamically adjusts the reuse ratio according to the temperature deviation of the preheating section, that is, the reuse ratio increases by 5% for every 1°C decrease in the preheating section temperature, and decreases by 5% for every 1°C increase in the preheating section temperature; when the concentration of organic components in the pyrolysis gas in the storage tank is above 20%, the control unit limits the maximum reuse ratio of pyrolysis gas in the storage tank to 80%, and the excess pyrolysis gas is stored in the storage tank. By specifically defining the quantitative rules for automatically adjusting the reuse ratio, the stability of the preheating section temperature under different operating conditions is ensured.

[0010] Preferably, the dynamic sealing structure includes a main seal, an annular buffer chamber, and a secondary seal connected in series. The main seal is made of graphite filler resistant to high temperatures and fluorine corrosion, or filled with polytetrafluoroethylene material. The secondary seal uses an inert gas seal. The annular buffer chamber is equipped with a negative pressure suction port and a fluoride concentration sensor. By setting up a main seal, an annular buffer chamber, and a secondary seal connected in series, combined with online monitoring of fluorine content, the problem of corrosion leakage of fluorine-containing pyrolysis gas is solved.

[0011] Preferably, in the tunnel-type pyrolysis furnace, the preheating section temperature is 300-400℃, and the pyrolysis section temperature is 400-480℃. Single-glass photovoltaic modules and double-glass photovoltaic modules undergo pyrolysis simultaneously in the pyrolysis section. Within this temperature range, the EVA in the double-glass photovoltaic module is completely pyrolyzed and vaporized, while the polyvinyl fluoride backing adhesive in the single-glass photovoltaic module is also fully pyrolyzed, achieving efficient and compatible processing of the two types of photovoltaic modules under the same pyrolysis conditions.

[0012] Preferably, the bottom of the automatic feeding system is connected to an anti-clogging vibration device, and the bottom of the tunnel pyrolysis furnace is equipped with a chain-type flexible scraper conveyor. By setting up the anti-clogging vibration device and the flexible scraper conveyor, continuous and reliable material conveying is ensured.

[0013] Preferably, the system also includes a bag filter unit and an alkaline scrubbing tower for deep treatment of the exhaust gas from the tunnel pyrolysis furnace, wherein the bag filter unit and the alkaline scrubbing tower are connected in series. This structure enables the exhaust gas to meet emission standards.

[0014] Preferably, the cooling discharge system includes a cooling kiln and a discharge conveyor chain. The cooling kiln is installed on the discharge conveyor chain to cool the material on the chain. This structure enables safe and continuous cooling and discharge of pyrolysis products.

[0015] This invention also provides a method for integrated pyrolysis of single and double glass photovoltaic modules, the method comprising the following steps: S100, the control unit controls the automatic feeding system to automatically feed single and double glass decommissioned photovoltaic modules, remove junction boxes and aluminum frames; at the same time, based on the module identification system, it identifies the specific type of materials in the automatic feeding system; S200, the control unit controls the temperature of the pyrolysis section of the tunnel pyrolysis furnace to be set to 400-480℃, so that single-glass photovoltaic modules and double-glass photovoltaic modules can be pyrolyzed simultaneously in the pyrolysis section; S300: The dynamic sealing structure set at both ends of the tunnel pyrolysis furnace enables the pyrolysis chamber of the tunnel pyrolysis furnace to maintain a slight negative pressure, thereby controlling the gas delivery pump to collect the pyrolysis gas generated during the pyrolysis process in a directional manner. S400: Based on the concentration of collected pyrolysis gas and the temperature of the preheating section, the control unit controls the gas delivery pump to adjust the recovery ratio of the collected pyrolysis gas delivered to the preheating section. The S500 control unit controls the cooling discharge system to cool the pyrolyzed material to a set temperature before discharging it.

[0016] This method organically links the functions of each part of the device, forming a complete process chain of "disassembly—identification—simultaneous pyrolysis—gas recovery—co-combustion—cooling and discharge". Compared with batch processing methods, this method eliminates the temperature adjustment and furnace cooling waiting time when changing materials, increases the effective operating time of the equipment by more than 30%, and significantly improves the processing capacity.

[0017] Compared with the prior art, the present invention has the following beneficial technical effects: (1) By setting dynamic sealing structures at both ends of the tunnel pyrolysis furnace, the present invention achieves a slight negative pressure in the inner cavity of the tunnel pyrolysis furnace, realizes the directional collection of pyrolysis gas, effectively reduces the leakage of pyrolysis gas, and realizes the safe handling of single-glass photovoltaic modules by the tunnel pyrolysis furnace.

[0018] (2) The present invention reduces the consumption of external natural gas and saves costs by using pyrolysis gas recycling in conjunction with external natural gas combustion for heating.

[0019] (3) By uniformly controlling the pyrolysis section temperature at 400-480℃, this invention enables the simultaneous processing of single-glass photovoltaic modules and double-glass photovoltaic modules in the same pyrolysis furnace. Within this temperature range, both the EVA layer of the double-glass photovoltaic module and the polyvinyl fluoride backing layer of the single-glass photovoltaic module can be fully pyrolyzed, and the two types of modules do not interfere with each other, overcoming the technical bias in the prior art that the two types of modules cannot be processed simultaneously in the same equipment due to their different pyrolysis temperature requirements.

[0020] (4) The present invention realizes the identification and recording of material types through the component identification system, which facilitates production management and process traceability. At the same time, it provides a material ratio reference for the control unit to adjust the pyrolysis gas recycling ratio, so that the entire pyrolysis system can automatically adjust the combustion parameters according to the ratio of the mixed materials, further improving the intelligence level and processing efficiency of the system. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of an integrated pyrolysis device for single and double glass decommissioned photovoltaic modules in this invention.

[0023] Figure 2 This is a structural block diagram of the dynamic sealing structure in this invention.

[0024] Figure 3 This is a top view of the integrated pyrolysis device for single and double-glass decommissioned photovoltaic modules.

[0025] Figure 4 This is a flowchart of an integrated pyrolysis method for single and double-glass decommissioned photovoltaic modules according to the present invention.

[0026] In the diagram: 1. Automatic feeding system, 2. Component identification system, 3. Tunnel pyrolysis furnace, 31. Preheating section, 32. Pyrolysis section, 33. Dynamic sealing structure, 331. Main seal, 332. Annular buffer chamber, 333. Secondary seal, 334. Negative pressure suction port, 335. Fluoride concentration sensor, 4. Gas delivery pump, 5. Cooling discharge system, 51. Cooling kiln, 52. Discharge conveyor chain, 6. Purification system, 7. Gas storage tank. Detailed Implementation

[0027] To make the objectives, technical solutions, and technical effects of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings, multiple embodiments, and comparative examples. In the following description, the same components are referred to by the same reference numerals.

[0028] Traditionally, single-glass and double-glass photovoltaic modules are considered difficult to achieve the same treatment effect under the same pyrolysis conditions due to differences in the composition and content of organic matter. However, by controlling the temperature of pyrolysis section 32 within the range of 400-480℃, both types of modules can achieve complete pyrolysis. The specific analysis is as follows: The main organic component of double-glass photovoltaic modules is EVA (ethylene-vinyl acetate copolymer), which has a pyrolysis temperature range of 350-450℃. At 400-450℃, EVA can be completely pyrolyzed and vaporized without residue.

[0029] In addition to the EVA layer, single-glass photovoltaic modules also contain a polyvinyl fluoride (PVF) backing layer. PVF has a higher decomposition temperature than EVA, requiring a temperature range of 430-480℃ for complete decomposition. However, PVF accounts for a relatively small percentage of the mass of a single-glass photovoltaic module (typically 2-4% of the total module mass). When the temperature in the pyrolysis section 32 reaches above 430℃, PVF begins to decompose significantly; when the temperature reaches 460℃, PVF can decompose completely.

[0030] Fluorine-containing pyrolysis gas (mainly hydrogen fluoride, fluoromethane, etc.) generated by the pyrolysis of single-glass photovoltaic modules and hydrocarbon pyrolysis gas generated by double-glass photovoltaic modules can both be effectively collected and transported to the preheating section 31 for co-combustion within the same temperature range of 400-480℃. After the pyrolysis gases of the two types of modules are mixed in the collection pipeline, their calorific values ​​can complement each other (the calorific value of single-glass pyrolysis gas is about 45MJ / Nm³, and the calorific value of double-glass pyrolysis gas is about 50MJ / Nm³). The calorific value fluctuation range of the mixed pyrolysis gas is narrower than that of single-type modules, which is beneficial to the stable operation of the combustion system.

[0031] Therefore, by controlling the temperature of the pyrolysis section 32 within the range of 400-480℃, and in conjunction with the dynamic sealing structure 33 and the micro-negative pressure environment, single-glass and double-glass photovoltaic modules can be processed simultaneously in the same pyrolysis furnace, and both can achieve ideal separation results.

[0032] In this invention, the component identification system 2, in addition to identifying material types, can also count the quantity or weight ratio of single-glass and double-glass photovoltaic modules and transmit this ratio information to the control unit. Based on the single / double-glass ratio in the mixture and combined with real-time data from the pyrolysis gas concentration sensor, the control unit automatically adjusts the following combustion parameters: When the proportion of double-glass photovoltaic modules is high (>60%), the hydrocarbon content in the pyrolysis gas is high and the calorific value is relatively stable. The control unit appropriately reduces the response speed of the pyrolysis gas reuse ratio adjustment and mainly supplies gas from the gas storage tank 7. When the proportion of single-glass photovoltaic modules is high (>60%), the fluoride content in the pyrolysis gas increases and the gas production rate fluctuates greatly. The control unit increases the response speed of the pyrolysis gas recycling ratio adjustment and increases the negative pressure suction power of the annular buffer chamber 332. When the proportions of the two types of components are close (each accounting for about 50%), the composition of the pyrolysis gas is the most complex and the calorific value fluctuates the most. The control unit activates the large-capacity buffer mode of the gas storage tank 7 to suppress the concentration fluctuation of the pyrolysis gas to the greatest extent.

[0033] Through the aforementioned adaptive adjustment mechanism, this invention achieves stable operation under varying material ratios.

[0034] Example 1 Example 1 provides an integrated pyrolysis device for single and double-glass decommissioned photovoltaic modules, such as... Figures 1-3 As shown, the specific structure is as follows: Automatic feeding system 1 and component identification system 2, wherein: The automatic feeding system 1 includes a buffer silo, a feeding conveyor belt and a six-axis robot. The bottom of the buffer silo is equipped with an anti-clogging vibration device (electromagnetic vibrator, periodic vibration). The six-axis robot is used to remove the junction box and aluminum frame. The disassembled laminated parts are laid in a single layer and enter the tunnel pyrolysis furnace 3. The component identification system 2 uses a visual recognition camera or weight recognition sensor, which is installed above the feeding conveyor belt to distinguish between single-glass photovoltaic modules and double-glass photovoltaic modules and to count their respective quantities or weight ratios. The identification signal of the component identification system 2 is transmitted to the control unit (such as a PLC controller). The control unit automatically adjusts the gas supply strategy of the gas storage tank 7 and the air distribution parameters of the burner coupling interface based on the ratio of single-glass to double-glass components in the mixture and the real-time data fed back by the pyrolysis gas concentration sensor.

[0035] Tunnel pyrolysis furnace 3: The pyrolysis furnace has a total length of 12m, including a 3m preheating section 31, a 7m pyrolysis section 32, and a 2m transition section. The preheating section 31 is equipped with four gas burners (each with a power of 50kW). The gas burners are connected to external natural gas pipelines and pyrolysis gas recycling pipelines through burner coupling interfaces. The pyrolysis section 32 is equipped with electric heating tubes (independently controlled in three zones). The temperature of the pyrolysis section 32 is controlled within the range of 400-480℃ to allow single-glass and double-glass photovoltaic modules entering the pyrolysis furnace to undergo pyrolysis simultaneously.

[0036] The furnace chamber of the pyrolysis furnace is made of 310S heat-resistant stainless steel. Dynamic sealing structures 33 are set at the openings at both ends. A chain-type flexible scraper conveyor (chain drives nylon scraper) is set at the bottom of the furnace chamber. The conveying speed of the conveyor is adjustable in the range of 0.1-0.5m / min. The pyrolysis chamber of the pyrolysis furnace is connected to the gas delivery pump 4 through the gas collection pipe, thereby maintaining a slightly negative pressure state in the pyrolysis chamber (such as -50Pa, -80Pa or -150Pa).

[0037] The dynamic sealing structure 33 includes a main seal 331, an annular buffer chamber 332, and a secondary seal 333 connected in series. The main seal 331 is made of graphite filler or polytetrafluoroethylene (PTFE) material that is resistant to high temperature and fluorine corrosion and is in close contact with the outer wall of the furnace. The annular buffer chamber 332 is equipped with a negative pressure suction port 334 and a fluoride concentration sensor 335. The secondary seal 333 adopts an inert gas (nitrogen) gas seal to form a gas curtain barrier. Based on the dynamic sealing structure 33, the problem of fugitive emission of fluorine-containing gas is completely solved.

[0038] Gas delivery pump 4 and burner coupling interface: The gas delivery pump 4 uses a high-temperature centrifugal fan (temperature resistant up to 450℃), and the burner coupling interface is a specially designed three-channel low-NOx burner for natural gas / pyrolysis gas / air, which allows pyrolysis gas and external natural gas to be premixed or mixed and burned in the same burner, avoiding the risk of flameout or deflagration caused by concentration fluctuations when pyrolysis gas is burned alone.

[0039] Purification system 6 and gas storage tank 7: Purification system 6 includes a cyclone dust collector and an activated carbon adsorption tank connected in series to remove particulate matter and some tar from the pyrolysis gas, preventing blockage of valves and burners. The purified pyrolysis gas enters the gas storage tank 7 (gas storage tank 7 has a volume of 5-10 m³). 3 The gas storage tank (with an inner fluoroplastic anti-corrosion lining) stores excess pyrolysis gas when the pyrolysis gas production exceeds the reuse demand, and replenishes the released amount when the pyrolysis gas production is insufficient. The outlet end of the gas storage tank 7 is connected to the burner coupling interface through pipes and valves.

[0040] The control unit automatically adjusts the opening of the gas supply valve of the gas storage tank 7 based on the pressure inside the gas storage tank 7, the pyrolysis gas concentration (detected by an online infrared calorimeter), the temperature feedback of the preheating section 31, and the single-glass / double-glass ratio information provided by the component identification system 2, thereby realizing the adjustment of the pyrolysis gas reuse ratio. The specific adjustment of the pyrolysis gas reuse ratio is as follows: When the concentration of organic components in the pyrolysis gas in storage tank 7 is below 8% (the calorific value is too low to burn stably), the reuse is shut off, and 100% external natural gas is used. When the concentration of organic components in the pyrolysis gas in the gas storage tank 7 is between 8% and 20%, the temperature deviation of the preheating section 31 is dynamically adjusted. For every 1°C undertemperature, the reuse ratio increases by 5%, and for every 1°C overtemperature, the reuse ratio decreases by 5%. When the concentration of organic components in the pyrolysis gas in the gas storage tank 7 is higher than 20%, the maximum reuse ratio of the pyrolysis gas is limited to 80%, and the excess gas is stored in the gas storage tank 7.

[0041] By setting up a gas storage tank 7 and combining it with the material ratio information provided by the component identification system 2, the present invention can automatically adjust the energy management strategy according to the change of the single-glass / double-glass mixing ratio, thus solving the problem of energy supply and demand imbalance caused by the fluctuation of gas production rate and composition during the pyrolysis of mixed materials.

[0042] Cooling discharge system 5: The cooling discharge system 5 includes a cooling kiln 51 and a discharge conveyor chain 52. The cooling kiln 51 adopts a rotary indirect water-cooled structure (cooling water is circulated through the jacket) and is installed at the front end of the discharge conveyor chain 52. The pyrolyzed material falls from the discharge end of the tunnel pyrolysis furnace 3 onto the discharge conveyor chain 52. During the conveying process of the clinker conveyor chain, the cooling kiln 51 cools the pyrolyzed material to a set temperature (such as below 60°C) and then the material is sent to the subsequent sorting system by the discharge conveyor chain 52.

[0043] Exhaust gas deep treatment system: It includes a series-connected bag filter unit (metal membrane filter bags, filtration accuracy 0.1μm, used to remove particulate matter) and an alkaline scrubbing tower (two-stage countercurrent packed tower, liquid-to-gas ratio 4-6L / m³). 3 The absorbent is a 5% NaOH solution, used to absorb acidic gases such as HF and HCl.

[0044] Control unit: The control unit adopts a Siemens S7-1200 PLC with a built-in fuzzy PID algorithm. It is connected to the automatic feeding system 1, component identification system 2, natural gas heating device, electric heating device, gas transfer pump 4, gas storage tank 7 valve, and cooling discharge system 5 to realize full-process automatic control.

[0045] In the above embodiment, the pyrolysis device first completes the disassembly and feeding through the automatic feeding system 1, and distinguishes the material type and calculates the proportion based on the component identification system 2 during the feeding process; then, it adopts a partitioned structure of preheating section 31 and pyrolysis section 32, and controls the temperature of pyrolysis section 32 at 400-480℃, so that single-glass and double-glass photovoltaic modules are pyrolyzed simultaneously in the same pyrolysis furnace, and the combustion parameters are automatically adjusted based on the material proportion information; finally, the pyrolysis products are cooled and discharged through the cooling discharge system 5.

[0046] This pyrolysis device enables the simultaneous and safe processing of single-glass and double-glass photovoltaic modules in the same tunnel-type pyrolysis furnace 3. Based on the dynamic sealing structure 33 and the slight negative pressure of the tunnel-type pyrolysis furnace 3, the leakage rate of pyrolysis gas is reduced from 15-25% in the prior art to below 0.5%. By reusing pyrolysis gas in conjunction with external natural gas combustion for heating, natural gas consumption is effectively reduced by 15%-20%. Utilizing a unified pyrolysis temperature range of 400-480℃, both types of modules achieve ideal separation results (separation rate ≥98.8%), realizing efficient integrated and compatible processing of single-glass and double-glass photovoltaic modules.

[0047] Example 2 Example 2 provides a method for integrated pyrolysis of single and double glass photovoltaic modules using the pyrolysis device described above, such as... Figure 4 As shown, the method includes the following steps: S100, the control unit controls the automatic feeding system 1 to automatically feed single and double glass decommissioned photovoltaic modules, remove junction boxes and aluminum frames; at the same time, based on the module identification system, the specific type of materials in the automatic feeding system 1 is identified and the ratio of single glass / double glass is calculated; S200, the control unit controls the temperature of the pyrolysis section 32 of the tunnel pyrolysis furnace 3 to be set to 400-480℃, so that single-glass photovoltaic modules and double-glass photovoltaic modules are pyrolyzed simultaneously in the pyrolysis section 32; at the same time, the control unit presets the initial reference ratio of pyrolysis gas recycling according to the single-glass / double-glass ratio information in the material. S300, the dynamic sealing structure 33 set at both ends of the tunnel pyrolysis furnace 3 makes the pyrolysis chamber of the tunnel pyrolysis furnace 3 maintain a slight negative pressure, thereby controlling the gas delivery pump 4 to collect the pyrolysis gas generated during the pyrolysis process in a directional manner. S400. Based on the collected pyrolysis gas concentration and the temperature of the preheating section 31, and combined with the single-glass / double-glass ratio information identified in step S100, the control unit controls the gas delivery pump 4 and the valve of the gas storage tank 7 to adjust the recovery ratio of the collected pyrolysis gas delivered to the preheating section 31. S500, the control unit controls the cooling discharge system 5 to cool the pyrolyzed material to the set temperature before discharging it.

[0048] The above embodiments describe a complete control process from material feeding for single- and double-glass photovoltaic modules to the completion of pyrolysis. Specifically, step S100 achieves automatic material feeding, disassembly, identification, and proportion statistics; step S200 sets the temperature of the pyrolysis section 32 uniformly at 400-480℃, enabling simultaneous processing of single-glass and double-glass photovoltaic modules under the same pyrolysis conditions; step S300 achieves directional collection of pyrolysis gas through a dynamic sealing structure 33 and micro-negative pressure; step S400 automatically adjusts the recycling ratio based on material proportion information and pyrolysis gas concentration information; and step S500 achieves cooled discharge of the pyrolysis material.

[0049] This pyrolysis method organically links the functions of each part of the device, forming a complete process chain of "material feeding and dismantling - material identification and proportion statistics - simultaneous pyrolysis of materials - pyrolysis gas recovery - synergistic combustion of pyrolysis gas and natural gas - cooling and discharge of pyrolysis materials". It has excellent technical effects in terms of environmental protection, energy consumption, processing efficiency and separation effect.

[0050] To further illustrate the technical effects and principles of the present invention, a comparative experiment and the pyrolysis apparatus and pyrolysis method provided by the present invention are presented below.

[0051] Comparative Experiment 1 This comparative experiment verifies the effect of the dynamic sealing structure 33 of the present invention on controlling the leakage rate of pyrolysis gas in the tunnel pyrolysis furnace 3, and its influence on the fluoride concentration and pyrolysis separation effect in the working environment. The experimental material is a mixture of single-glass and double-glass decommissioned photovoltaic modules from the same batch (single-glass:double-glass = 1:1, total processing capacity 1 ton).

[0052] The experimental group used the pyrolysis apparatus of Example 1, wherein the main seal 331 of the tunnel pyrolysis furnace 3 is filled with PTFE / graphite packing, the secondary seal 333 is a nitrogen gas seal, the annular buffer chamber 332 is equipped with negative pressure suction, the temperature of the preheating section 31 is set to 350℃, and the temperature of the pyrolysis section 32 is set to 450℃.

[0053] The difference between the control group and the experimental group is that the pyrolysis furnace is a traditional open tunnel furnace with no dynamic sealing structure 33, and the gap between the furnace liner and the outer shell is naturally sealed. The other configurations are the same as those of the experimental group. The results of the comparative experiment 1 are shown in Table 1.

[0054]

[0055] As shown in Table 1, the pyrolysis device provided by this invention can control the pyrolysis gas leakage rate to below 0.5% by setting the dynamic sealing structure 33, and the fluoride concentration at the working site is only 0.09 mg / m³, with an average separation rate as high as 99.0%. Compared with the control group, the pyrolysis gas leakage rate is reduced by 98.2%, the fluoride concentration at the working site is reduced by 98.0%, and the pyrolysis separation rate is increased by 53.5%. Therefore, by setting the dynamic sealing structure 33 at both ends of the tunnel pyrolysis furnace 3, this invention successfully solves the technical problem of fugitive emission of pyrolysis gas in existing tunnel pyrolysis furnace 3, and realizes safe, efficient, and environmentally friendly treatment of single-glass and double-glass photovoltaic modules in the same tunnel pyrolysis furnace 3.

[0056] Comparative Experiment 2 This comparative experiment was conducted to verify the control effect of the present invention on the temperature stability and natural gas consumption of the preheating section 31 by automatically adjusting the pyrolysis gas recycling ratio through the control unit. The experimental material was a mixture of decommissioned photovoltaic modules (60% single-glass photovoltaic modules and 40% double-glass photovoltaic modules, with a total processing capacity of 5 tons), which was fed in 10 batches of 0.5 tons each.

[0057] The experimental group used the pyrolysis device of Example 1 and the pyrolysis method of Example 2 to pyrolyze the experimental materials; the difference between the control group and the experimental group was that the control unit controlled the pyrolysis gas reuse ratio to be fixed at 50% and the natural gas replenishment amount to be fixed.

[0058] The experimental procedure is as follows: 1. Equipment preparation, including: In the control group, the automatic adjustment function was turned off in the control unit, the fixed reuse ratio of pyrolysis gas was set to 50%, and the opening of the natural gas valve was fixed to a preset value that matched the 50% pyrolysis gas reuse ratio. In the experimental group, the automatic adjustment function was enabled in the control unit, that is, the control algorithm for automatically adjusting the recycling ratio was loaded. The threshold values ​​for the concentration of organic components in the pyrolysis gas were 8% and 20%, the temperature feedback coefficient was 5% / ℃, and the upper limit of the recycling ratio was 80%. 2. Three temperature measuring points are set along the axial direction in the preheating section 31 of the two pyrolysis furnaces, namely the inlet, middle and outlet. A thermocouple (accuracy ±0.5℃) is installed at each temperature measuring point and connected to the data acquisition system. The sampling frequency is 1 time / 10 seconds. 3. Both sets of pyrolysis furnaces continuously feed 5 tons of mixed components, and run for about 5 hours. Record the temperature, natural gas consumption and pyrolysis gas concentration at each measuring point in the preheating section 31. The experimental group also needs to record the gas inlet and outlet of the gas storage tank 7 and the valve opening. 4. Calculate the average temperature, standard deviation, and overall temperature fluctuation range of each measuring point in the two sets of experiments during the stable operation phase. 5. Record the cumulative natural gas consumption of the two sets of experiments, and calculate the natural gas consumption per unit of the two sets of experiments.

[0059] The results of the comparative experiment 1 are shown in Table 2.

[0060]

[0061] As can be seen from Table 2, compared with the control group, the present invention can reduce the temperature fluctuation range of the preheating section 31 from 73°C to 12°C by setting an automatic adjustment mechanism for the pyrolysis gas reuse ratio, thereby reducing natural gas consumption by 18.7%.

[0062] Comparative Experiment 3 This comparative experiment was conducted to verify the feasibility and effectiveness of the present invention in simultaneously performing pyrolysis treatment on single-glass and double-glass photovoltaic modules within a temperature range of 400-480℃.

[0063] The experiment consisted of three groups, all using the pyrolysis apparatus of Example 1 and the pyrolysis method of Example 2, with the temperature of pyrolysis section 32 set to 450℃ in all groups. The materials used in the three experiments were as follows: Experimental Group A: Pure Double-Glass Photovoltaic Modules (1 ton) Experimental Group B: Pure Single-Glass Photovoltaic Modules (1 ton) Experimental Group C: Mixture of single-glass and double-glass materials (1:1 weight ratio, total weight 1 ton) The temperature of the pyrolysis section 32 in all three experiments was set to 450℃. The results of the comparative experiment 3 are shown in Table 3.

[0064]

[0065] As can be seen from Table 3: Experimental Group A (Pure Double Glass): At 450℃, the EVA of the double-glass photovoltaic module was completely pyrolyzed, and the glass remained intact with a separation rate of up to 99.5%.

[0066] Experimental Group B (Pure Single Glass): At 450℃, the polyvinyl fluoride backing adhesive of the single glass photovoltaic module was fully pyrolyzed, and the glass and silicon wafer separated naturally, with a separation rate of up to 98.8%.

[0067] Experimental Group C (mixed materials): At 450℃, the separation rate of double-glass photovoltaic modules reached 99.2% and the breakage rate was only 0.6%; the separation rate of single-glass photovoltaic modules reached 98.5% and the breakage rate was only 1.0%, which was basically equivalent to the effect of individual treatments.

[0068] The above results demonstrate that when the temperature of pyrolysis section 32 is controlled at 450℃, both single-glass and double-glass photovoltaic modules achieve ideal separation effects, whether processed individually or in combination. This fully verifies the feasibility and superiority of the technical solution of controlling the temperature of pyrolysis section 32 within the range of 400-480℃, enabling simultaneous processing of single-glass and double-glass photovoltaic modules in the same pyrolysis furnace, and overcomes the technical prejudice in this field that "single-glass and double-glass modules must be processed in batches."

[0069] Comparative Experiment 4 This comparative experiment was conducted to verify the separation effect of single-glass and double-glass photovoltaic modules under different temperature conditions (400℃, 430℃, 450℃, 480℃) in order to determine the optimal unified pyrolysis temperature range.

[0070] The experiment used a mixture of materials (single-glass:double-glass = 1:1) and pyrolyzed them at four temperatures: 400℃, 430℃, 450℃, and 480℃, while keeping other conditions constant. The experimental results are shown in Table 4.

[0071]

[0072] As can be seen from Table 4: When the temperature of pyrolysis section 32 is 400℃, the separation rate of double-glass photovoltaic modules has reached 92.3%. However, due to insufficient temperature, the pyrolysis of polyvinyl fluoride backing adhesive in single-glass photovoltaic modules is incomplete, and the separation rate is only 71.5%, which cannot meet the requirements of industrial production.

[0073] When the temperature of pyrolysis section 32 is 430℃, the separation rate of double-glass photovoltaic modules increases to 98.6%, and the separation rate of single-glass photovoltaic modules also increases to 90.2%, but about 10% of single-glass photovoltaic modules are still not completely separated.

[0074] When the temperature of pyrolysis section 32 is 450℃, the separation rates of double-glass photovoltaic modules and single-glass photovoltaic modules reach 99.2% and 98.5% respectively, both achieving ideal separation effects.

[0075] When the temperature of pyrolysis section 32 is 480℃, the separation rate of single-glass photovoltaic modules is further improved to 99.0%, but the glass breakage rate of double-glass photovoltaic modules increases significantly to 3.8% due to the excessively high temperature, which affects the quality of the recycled products.

[0076] Based on the above results, controlling the temperature of pyrolysis section 32 within the range of 430-480℃ can effectively process both types of modules. 450℃ is the optimal temperature point, ensuring sufficient pyrolysis of the adhesive in single-glass photovoltaic modules (separation rate ≥98.5%) while preventing double-glass photovoltaic modules from cracking due to excessive temperature (breakage rate ≤1.0%). This fully verifies the rationality and feasibility of the technical solution of setting the temperature of pyrolysis section 32 to 400-480℃ in this invention.

[0077] The above provides a detailed description of the integrated pyrolysis apparatus and method for single- and double-glass decommissioned photovoltaic modules provided in this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are merely for the purpose of helping to understand the core ideas of this application. It should be noted that those skilled in the art can make various improvements and modifications to this application without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of this application.

Claims

1. An integrated pyrolysis device for single and double-glass decommissioned photovoltaic modules, characterized in that, include: An automated feeding system is used for the automatic feeding of single and double glass decommissioned photovoltaic modules, removal of junction boxes, and disassembly of aluminum frames. The component identification system, which is installed in the automatic feeding system, is used to identify the type of single- or double-glass decommissioned photovoltaic modules; The tunnel pyrolysis furnace is connected to the output end of the automatic feeding system. The tunnel pyrolysis furnace is divided into a preheating section and a pyrolysis section along the material conveying direction. The preheating section is equipped with a natural gas heating device for heating the preheating section, and the pyrolysis section is equipped with an electric heating device for controlling the temperature of the pyrolysis section. The tunnel pyrolysis furnace has openings at both ends and is connected with a dynamic sealing structure. A gas transfer pump is used to collect pyrolysis gas generated by the tunnel pyrolysis furnace. The inlet end of the gas transfer pump is connected to the pyrolysis gas outlet of the tunnel pyrolysis furnace, and the outlet end of the gas transfer pump is connected to a natural gas heating device to co-combust the collected pyrolysis gas with external natural gas to provide heat for the preheating section. The cooling discharge system is connected to the output end of the tunnel pyrolysis furnace and is used to cool the pyrolyzed material to a set temperature before discharging it. The control unit is connected to the automatic feeding system, the component identification system, the natural gas heating device, the electric heating device, the gas delivery pump, and the cooling discharge system.

2. The integrated pyrolysis device for single and double-glass decommissioned photovoltaic modules according to claim 1, characterized in that, The outlet end of the gas delivery pump is connected to a burner coupling interface, and the gas delivery pump is connected to the natural gas heating device through the burner coupling interface.

3. The integrated pyrolysis device for single and double-glass decommissioned photovoltaic modules according to claim 1, characterized in that, It also includes a purification system and a gas storage tank connected in series. The inlet end of the purification system is connected to the outlet end of the tunnel pyrolysis furnace to purify the pyrolysis gas discharged from the tunnel pyrolysis furnace. The inlet end of the gas storage tank is connected to the outlet end of the purification system to store the purified pyrolysis gas. The control unit is connected to the gas storage tank to adjust the reuse ratio of the pyrolysis gas in the gas storage tank according to the concentration of the pyrolysis gas in the gas storage tank and the heating load of the tunnel pyrolysis furnace.

4. The integrated pyrolysis device for single and double-glass decommissioned photovoltaic modules according to claim 3, characterized in that, The control unit adjusts the reuse ratio of pyrolysis gas in the storage tank as follows: when the concentration of organic components in the pyrolysis gas in the storage tank is below 8%, the reuse of pyrolysis gas in the storage tank is turned off; when the concentration of organic components in the pyrolysis gas in the storage tank is between 8% and 20%, the control unit dynamically adjusts the reuse ratio according to the temperature deviation of the preheating section, that is, the reuse ratio increases by 5% for every 1°C decrease in the preheating section temperature and decreases by 5% for every 1°C increase in the preheating section temperature; when the concentration of organic components in the pyrolysis gas in the storage tank is above 20%, the control unit limits the maximum reuse ratio of pyrolysis gas in the storage tank to 80%, and the excess pyrolysis gas is stored in the storage tank.

5. The integrated pyrolysis device for single and double-glass decommissioned photovoltaic modules according to claim 1, characterized in that, The dynamic sealing structure includes a main seal, an annular buffer chamber, and a secondary seal connected in series. The main seal is made of graphite filler that is resistant to high temperature and fluorine corrosion or filled with polytetrafluoroethylene material. The secondary seal adopts an inert gas seal. The annular buffer chamber is equipped with a negative pressure suction port and a fluoride concentration sensor.

6. The integrated pyrolysis device for single and double-glass decommissioned photovoltaic modules according to claim 1, characterized in that, In the tunnel-type pyrolysis furnace, the preheating section temperature is 300-400℃, the pyrolysis section temperature is 400-480℃, and single-glass photovoltaic modules and double-glass photovoltaic modules are pyrolyzed simultaneously in the pyrolysis section.

7. The integrated pyrolysis device for single and double-glass decommissioned photovoltaic modules according to claim 1, characterized in that, The bottom of the automatic feeding system is connected to an anti-clogging vibration device, and the bottom of the tunnel pyrolysis furnace is equipped with a chain-type flexible scraper conveyor.

8. The integrated pyrolysis device for single and double-glass decommissioned photovoltaic modules according to claim 1, characterized in that, It also includes a bag filter dust collection unit and an alkaline scrubbing tower for deep treatment of the exhaust gas discharged from the tunnel pyrolysis furnace, wherein the bag filter dust collection unit and the alkaline scrubbing tower are connected in series.

9. The integrated pyrolysis device for single and double-glass decommissioned photovoltaic modules according to claim 1, characterized in that, The cooling discharge system includes a cooling kiln and a discharge conveyor chain. The cooling kiln is installed on the discharge conveyor chain to cool and reduce the temperature of the material on the discharge conveyor chain.

10. A method for integrated pyrolysis of single- and double-glass photovoltaic modules using the pyrolysis apparatus described in any one of claims 1-9, characterized in that, Includes the following steps: S100, the control unit controls the automatic feeding system to automatically feed single and double glass decommissioned photovoltaic modules, remove junction boxes and aluminum frames; at the same time, based on the module identification system, it identifies the specific type of materials in the automatic feeding system; S200, the control unit controls the temperature of the pyrolysis section of the tunnel pyrolysis furnace to be set to 400-480℃, so that single-glass photovoltaic modules and double-glass photovoltaic modules can be pyrolyzed simultaneously in the pyrolysis section; S300: The dynamic sealing structure set at both ends of the tunnel pyrolysis furnace enables the pyrolysis chamber of the tunnel pyrolysis furnace to maintain a slight negative pressure. The control unit then controls the gas delivery pump to collect the pyrolysis gas generated during the pyrolysis process in a directional manner. The slight negative pressure is -50Pa to -150Pa. S400: Based on the concentration of collected pyrolysis gas and the temperature of the preheating section, the control unit controls the gas delivery pump to adjust the recovery ratio of the collected pyrolysis gas delivered to the preheating section. The S500 control unit controls the cooling discharge system to cool the pyrolyzed material to a set temperature before discharging it.

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