Equipment and method for intelligently sorting waste photovoltaic module and recovering silicon wafers

Abstract

The invention discloses a device and method for intelligently sorting waste photovoltaic modules and recovering silicon wafers, the device comprises a box taking device, a frame dismantling mechanism, a sorting device, a hot knife device, a tunnel kiln, a screening device, a silver extracting machine and a master control unit, and the master control unit is provided with ResNet-18; the sorting device comprises an annular infrared light source, an area-array camera, a telecentric lens, a pneumatic push rod and a flow guide pipeline, wherein the pneumatic push rod and the flow guide pipeline are arranged on the two sides of the conveying belt respectively. The hot knife device comprises an upper driving roller, a lower driving roller, a vacuum chuck and a double-layer electric heating knife head, the conveying belt penetrates through a gap between the two driving rollers and is connected with the conveying belt at the tail end of the sorting device, and an air cooling fan and a copper solder strip absorbing device which are opposite in position are arranged behind the driving rollers; the tunnel kiln is connected with the screening device through a conveying belt, and discharging ports of the screening device and the hot knife device are connected with the silver extracting machine through conveying belts. Intelligent sorting of the waste photovoltaic modules is achieved, and high-value recovery and conversion of effective components of the waste photovoltaic modules are promoted.

Description

Technical Field

[0001] The present invention relates to a waste photovoltaic module recycling device, in particular to a device and method for intelligently sorting waste photovoltaic modules and recycling silicon wafers. Background Art

[0002] As the global energy transition accelerates, the scale of photovoltaic power generation installations continues to climb. According to data from the International Energy Agency (IEA), China will contribute 57.7% of the global share with 216.3GW of new installed capacity in 2023, and its cumulative installed capacity will exceed 600GW. However, due to the approximately 25-30 year life cycle of photovoltaic modules, it is estimated that by 2030, my country's discarded photovoltaic modules will reach 1.4 million tons, including over 168,000 tons of recyclable silicon materials and over 1.05 million tons of glass. Furthermore, discarded photovoltaic modules also contain valuable components such as aluminum and silver, which have extremely high resource utilization value. If discarded photovoltaic modules are not effectively recycled and utilized, it will cause significant resource waste and environmental pollution. Therefore, the recycling and treatment of waste solar silicon cells is imminent.

[0003] Given the immense demand for high-purity silicon wafers within the silicon-carbon anode industry chain, recycling high-purity silicon wafers from used solar cells for use in silicon-carbon anode manufacturing is the most common technology for recycling used solar cells. However, traditional recycling processes use thermal decomposition to recycle used solar panels, where the glass is recovered as small fragments. Compared to intact glass, broken glass is used in low-value-added building materials and can only replace 30% of ore consumption. Its recycling value is only 20% of that of intact glass, resulting in low-value glass recycling. Therefore, intelligent disassembly and sorting of used solar panels to recover intact glass is key to improving glass resource utilization.

[0004] In recent years, the intelligent manufacturing revolution, supported by new-generation information technology, has accelerated, driving the industrial production system to evolve in depth towards digitalization and autonomy. As an important pillar of national economic development, the manufacturing industry is taking cutting-edge scientific and technological applications as a starting point to fully grasp the opportunities for industrial upgrading driven by intelligent technology. This new production model, constructed by intelligent sensing devices, industrial Internet of Things and adaptive control systems, is reshaping the value creation model of the global manufacturing industry.

[0005] Therefore, it is expected to build a new intelligent sorting equipment for discarded photovoltaic modules to effectively realize the high-value utilization of valuable components in discarded photovoltaic modules. Summary of the Invention

[0006] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide an apparatus and method for intelligently sorting waste photovoltaic modules and recycling silicon wafers, thereby realizing the intelligent sorting of waste photovoltaic modules and promoting the high-value recovery of effective components of waste photovoltaic modules.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] An intelligent device for sorting discarded photovoltaic modules and recycling silicon wafers, comprising a box removal device, a frame removal mechanism, a sorting device, a hot knife device, a tunnel kiln, a screening device, a silver extractor, and a general control unit;

[0009] The box removal device, frame removal mechanism, sorting device and hot knife device are connected in sequence through a conveyor belt. The sorting device includes a support frame and a pneumatic push rod. An annular infrared light source is fixedly installed on the support frame, and an area array camera is fixedly installed below the annular infrared light source. The area array camera is connected to a telecentric lens via a C-Mount interface. The telecentric lens is connected to the main control unit, and the main control unit is deployed with a ResNet-18 model. The pneumatic push rod is installed on one side of the conveyor belt and connected to the main control unit. An inclined diversion pipe is provided on the other side of the conveyor belt, and the diversion pipe is connected to the feed port of the tunnel kiln.

[0010] The hot knife device includes a shell, a support fixedly arranged inside the shell, and two sets of upper and lower transmission rollers. The support is fixedly connected to a pair of ceramic heat insulation plates. The transmission roller is located between the pair of ceramic heat insulation plates. A gap is left between the upper and lower transmission rollers to form a feed port. The conveyor belt passes through the gap and connects with the conveyor belt at the tail end of the sorting device. A pressure sensor is fixedly embedded on the surface of the transmission roller; a movable and retractable connecting rod is installed on the top of the support, and a vacuum suction cup is fixedly connected to the lower end of the connecting rod. A double-layer electric heating knife head and a laser sensor are installed below the support. The double-layer electric heating knife head is connected to the heating device and fixedly installed with a temperature sensor. The pressure sensor, laser sensor, heating device and temperature sensor are all connected to the main control unit;

[0011] The support is also equipped with a back plate collection bin and a glass collection bin, as well as an air-cooling fan and a copper welding strip absorption device positioned opposite to each other, wherein: the back plate collection bin is located at the rear and lower part of the transmission roller, the glass collection bin is located on the side of the transmission roller, and an infrared imager for measuring temperature connected to the main control unit is installed on the top of the air-cooling fan;

[0012] The discharge port of the tunnel kiln is connected to the screening device through a conveyor belt. The screening device includes an upper screen for intercepting silicon cell fragments and a lower screen for intercepting copper welding strips. The end outlet of the upper screen is connected to the silver extractor through a conveyor belt. The silver extractor is also connected to the discharge port of the hot knife device through a conveyor belt.

[0013] Furthermore, it also includes a pulse dust collector, a TO furnace, an activated carbon adsorption box and an induced draft fan connected in sequence through pipelines;

[0014] The hot knife device and the tunnel kiln smoke exhaust port are both connected to the pulse dust collector through pipelines.

[0015] Furthermore, the box-taking device includes a box-taking platform and a three-axis truss manipulator. The width of the box-taking platform is greater than the width of the conveyor belt. The box-taking platform is provided with a groove for the conveyor belt to pass through. The plane where the conveyor belt is located coincides with the plane where the box-taking platform is located.

[0016] The three-axis truss manipulator is connected to the main control unit, which includes a manipulator and a three-axis truss for controlling the manipulator to move along the X, Y and Z directions. The manipulator is located above the box-picking platform, and the end effector of the manipulator is a scraper, and the blades of the two scrapers are set facing each other.

[0017] Furthermore, the frame removal mechanism includes a mounting frame and a support platform, the width of the support platform is greater than the width of the conveyor belt, and the support platform is provided with a groove for the conveyor belt to pass through, the plane where the conveyor belt is located coincides with the plane where the support platform is located, a light source is installed on the support platform, and the mounting frame is provided with a photosensor directly opposite to the light source position, and the photosensor is connected to the main control unit;

[0018] The mounting frame is also fixedly installed with a hydraulic power head connected to the main control unit, a mounting plate is fixedly installed under the hydraulic power head, a clamping spring is fixedly installed under the mounting plate, the lower end of the clamping spring is fixedly connected to a clamping plate, and four obliquely arranged mounting rods are hinged around the mounting plate, a reset spring is fixedly connected between each adjacent mounting rod, and a push rod perpendicular to the mounting rod is fixedly installed at the lower end of the mounting rod.

[0019] Furthermore, the tunnel kiln includes a preheating zone, a core reaction zone, and a cooling zone connected in sequence by a conveyor belt, wherein: the preheating zone is lined with 310S stainless steel, with a temperature range of 100-600°C; the core reaction zone is lined with silicon carbide ceramic, with a temperature range of 600-800°C, and is connected to a temperature detector and an air conditioning device; the cooling zone is provided with a water-cooling jacket, and the water inlet temperature of the water-cooling jacket is 20°C;

[0020] The temperature detector is a K-type thermocouple arranged at intervals of 1m along the axial direction of the tunnel kiln, and the K-type thermocouple is connected to the main control unit; the air conditioning device includes an electric air valve connected to the air supply pipe of the core reaction zone, and the electric air valve is connected to the air inlet of the centrifugal fan arranged outside the tunnel kiln.

[0021] Furthermore, the screening device also includes an air shock screening module, which includes an shock gas generator and an inert atmosphere gas supply bottle. The shock gas generator is located between the upper screen and the lower screen. The inert atmosphere gas supply bottle provides an shock inert atmosphere for the shock gas generator, thereby forming a pulsed high-pressure airflow between the upper screen and the lower screen.

[0022] Furthermore, the screening device is connected to a collection system via a conveyor belt, and the collection system includes a brazing belt collection box located at the end outlet of the lower screen and a glass fragment collection box located at the bottom of the lower screen.

[0023] Furthermore, the pulse dust collector includes a bracket, a purification box is fixedly installed on the bracket, a pulse trigger device is fixedly installed on the purification box, an ash hopper is fixedly connected to the lower part of the purification box, and a dust collection box is provided below the ash hopper;

[0024] A plurality of purification bags are arranged inside the purification box, and the purification box is connected to the smoke exhaust port of the tunnel kiln and the hot knife device through a pipeline.

[0025] Furthermore, the TO furnace includes a furnace shell, an independent combustion chamber is provided inside the furnace shell, a burner is installed at the end of the combustion chamber, and fins are arranged on the outer wall of the combustion chamber;

[0026] A ceramic fiber insulation layer is fixedly installed on the outer wall of the furnace shell, and a thermoelectric power generation chip is also provided inside the furnace shell. The hot end of the thermoelectric power generation chip is connected to the outer wall of the combustion chamber through a flexible thermal conductive material, and the cold end of the thermoelectric power generation chip is connected to the furnace shell through a flexible thermal conductive material. Electricity is generated through the temperature difference between the hot end and the cold end of the thermoelectric power generation chip.

[0027] A method for intelligently sorting waste photovoltaic modules and recycling silicon wafers comprises the following steps:

[0028] Step 1: Remove the junction box and aluminum frame of the waste photovoltaic module in sequence through the box removal device and the frame removal mechanism, and convey the waste photovoltaic module with the junction box and aluminum frame removed to the sorting device through the conveyor belt;

[0029] Step 2: A ring-shaped infrared light source is illuminated with an 80% duty cycle. The infrared light emitted transmits through the photovoltaic modules to be sorted. A high-resolution area array camera equipped with a telecentric lens triggers the image capture. The telecentric lens converts the transmitted infrared light signal into a digital image signal, which serves as the input of the ResNet-18 model deployed in the main control unit. Based on the output of the ResNet-18 model, the crack probability value is calculated. If the probability value for three consecutive frames is ≥0.98, the main control unit determines that the photovoltaic module is broken; otherwise, it is determined to be intact.

[0030] Step 3: Recycling silicon wafers, glass and copper soldering tapes from discarded photovoltaic modules. The specific process is as follows:

[0031] When the photovoltaic module is judged to be a complete photovoltaic module, the main control unit drives the conveyor belt to transport the complete photovoltaic module to the conveyor belt. As the conveyor belt runs, it enters the hot knife device from the feed port. Then two sets of transmission rollers clamp it firmly, start the double-layer electric hot knife head, preheat the double-layer hot knife head to 200-300℃, and slowly advance the hot knife head along the laminated interface of the photovoltaic panel at the set advancement speed to soften the EVA film and separate the glass and backboard from the silicon solar cell. During the cutting process, the temperature, advancement speed and force of the double-layer electric hot knife head are monitored in real time through the data fed back by the temperature sensor, laser sensor and pressure sensor. The operating parameters are automatically adjusted by the main control unit or appropriate human intervention is given. The operation intervention is determined; at the same time, a laser sensor is used to locate the double-layer electric heating blade in contact with the copper welding tape, and local heating is performed for 5 to 10 seconds to soften the connection between the copper welding tape and the silicon wafer; the vacuum suction cup array absorbs the peeled glass and moves it to the glass collection bin, and the backplane falls into the backplane collection bin under the transmission roller. The copper welding tape is attached to the silicon cell and is conveyed forward by the conveyor belt. The air-cooling fan is started to generate forced convection dry air, which completely peels the copper welding tape from the silicon wafer and is blown into the copper welding tape absorption device by air. The copper welding tape, silicon cell and complete glass in the recycled photovoltaic module are detected by the infrared imager. When the temperature of the silicon cell drops to room temperature, it is conveyed to the silver extractor via the conveyor belt;

[0032] When a photovoltaic module is determined to be a broken photovoltaic module, the main control unit drives the conveyor belt to transport the broken photovoltaic module to the front of the pneumatic push rod, which pushes the broken photovoltaic module to the entrance of the inclined diversion pipe. The broken photovoltaic module enters the tunnel kiln along the inclined diversion pipe for pyrolysis reaction. It undergoes preheating, pyrolysis and cooling in the tunnel kiln in sequence, removes the EVA adhesive layer and backboard, and obtains a mixture of silicon cell fragments, copper welding tape and glass, wherein: the preheating temperature is 100-600°C, the pyrolysis temperature is 600-800°C, and the pyrolysis time is 20 minutes. During the pyrolysis process, the oxygen content in the combustion zone is dynamically adjusted according to the real-time temperature; the cooled silicon cell fragments, copper welding tape and glass mixture are transported to the screening device via the conveyor belt. After vibration screening, the upper screen intercepts the silicon cell fragments, which are then transported to the silver extractor via the conveyor belt, while the lower screen intercepts the copper welding tape and the separated glass fragments and are collected separately;

[0033] Use the silver extraction machine to extract the silver electrode sheets from the silicon cell to obtain high-purity silicon wafers;

[0034] Step 4: Under the negative pressure generated by the induced draft fan, the organic waste gas generated during the operation of the hot knife device and the tunnel kiln is sent to the pulse dust collector, TO furnace and activated carbon adsorption box in sequence. The pollution in the waste gas is removed through dust removal, thermal decomposition and adsorption.

[0035] Compared with the prior art, the present invention has the following technical effects:

[0036] The present invention uses an annular infrared light source to trigger an area array camera to take pictures of the discarded photovoltaic modules to be sorted. The telecentric lens converts the projected light signals of the discarded photovoltaic modules into digital image signals, which serve as the input of the ResNet-18 model deployed in the main control unit. The main control unit calculates the crack probability value based on the features output by the ResNet-18 model to sort out the complete photovoltaic modules and the broken photovoltaic modules. For the complete photovoltaic modules, the EVA glue and copper welding tape are softened by a hot knife device to separate the glass, copper welding tape and silicon cell sheets; for the broken photovoltaic modules, the broken photovoltaic modules are pyrolyzed in a tunnel kiln to obtain a mixture of silicon cell fragments, copper welding tape and glass, which is then separated by a screening device. Separate silicon cell fragments, copper welding strips and broken glass; compared with traditional equipment that subject all photovoltaic modules to pyrolysis treatment, the present invention uses a sorting device to intelligently sort photovoltaic modules, thereby improving the recycling quality and value of discarded photovoltaic modules, reducing carbon emissions, and achieving high-value recovery of glass resources. At the same time, the silver in silicon cell fragments and silicon cell wafers is extracted by a silver extraction machine to recover high-purity silicon wafers, which can be used to prepare silicon-carbon negative electrodes, reducing silicon ore consumption; in addition, the sorting device of the present invention is not only simple in structure, but also uses the mature ResNet-18 model to extract the features of digital image signals, with low requirements on the amount of training data and computing resources, low maintenance costs, and high industrial value.

[0037] The present invention uses the negative pressure generated by the induced draft fan to make the exhaust gas generated by the hot knife device and the tunnel kiln flow through the pulse dust collector, the TO furnace and the activated carbon adsorption box in sequence, and removes dust, organic matter and other harmful gases in the exhaust gas through filtration, pyrolysis and adsorption, thereby solving the problems of "inefficient disassembly - waste of resources - secondary pollution" faced by the waste photovoltaic recycling field, and laying a good foundation for building a zero-waste photovoltaic industry chain.

[0038] The present invention arranges a temperature detector and an air regulating device inside the tunnel kiln to obtain the combustion temperature inside the core reaction zone in real time, and controls the air regulating device to supply oxygen to the core reaction zone according to the temperature, so that the pyrolysis reaction is carried out at the optimal temperature and optimal oxygen content, thereby fully removing the EVA glue and the backboard.

[0039] The present invention integrates an air-oscillation screening module into the screening device, thereby utilizing vibration-air-oscillation collaborative screening technology to shorten the screening time, improve the double-layer screen screening efficiency, and provide an inert atmosphere for the photovoltaic modules to prevent them from being oxidized during the screening process, thereby further improving the recovery quality of the effective components.

[0040] The present invention arranges fins on the outer wall of the combustion chamber to increase the heat exchange between the combustion chamber and the furnace shell, facilitates the preheating of the exhaust gas entering the furnace shell, and improves the combustion efficiency of the exhaust gas in the combustion chamber. At the same time, the cold end and hot end of the thermoelectric power generation chip are respectively connected to the furnace shell and the outer wall of the combustion chamber, and the temperature difference power generation is used to further achieve the effect of energy saving and efficiency improvement. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 : Schematic diagram of the overall structure of the present invention;

[0042] Figure 2 : A schematic structural diagram of the box removal device of the present invention;

[0043] Figure 3 : A schematic structural diagram of the frame removal mechanism of the present invention;

[0044] Figure 4 : A schematic structural diagram of a sorting device according to the present invention;

[0045] Figure 5 : A schematic top view of the pneumatic push rod of the present invention;

[0046] Figure 6 : A side view of the hot knife device of the present invention;

[0047] Figure 7 : Schematic diagram of the overall structure of the hot knife device of the present invention;

[0048] Figure 8 : A schematic structural diagram of a pulse dust collector according to the present invention;

[0049] Figure 9 : The structural schematic diagram of the TO furnace of the present invention;

[0050] Figure 10 : A schematic structural diagram of an activated carbon adsorption box of the present invention;

[0051] Figure 11 : A schematic structural diagram of a tunnel kiln according to the present invention;

[0052] Figure 12 : Flowchart of the present invention for recycling discarded photovoltaic modules;

[0053] Figure 13 : Process flow chart of the present invention;

[0054] Figure 14 : Flowchart of the ResNet-18 algorithm.

[0055] In the figure: 1. Box removal device; 2. Frame removal device; 3. Sorting device; 4. Hot knife device; 5. Tunnel kiln; 6. Screening device; 7. Silver extractor; 8. Pulse dust collector; 9. TO furnace; 10. Activated carbon adsorption box; 11. Induced draft fan; 12. Three-axis truss; 13. Manipulator; 14. Shovel; 15. Box removal platform; 16. Mounting frame; 17. Support platform; 18. Hydraulic power head; 19. Mounting plate; 20. Clamping spring; 21. Push rod; 22. Pressing plate; 23. Area array camera; 24. Annular infrared light source; 25. Telecentric lens; 26. Pneumatic push rod; 27. Preheating zone; 28. Core reaction zone; 29. Cooling zone; 30. Diversion duct; 31 , upper screen; 32. Lower screen; 33. Aggregation system; 34. Feed port; 35. Conveyor belt; 36. Drive roller; 37. Vacuum suction cup; 38. Double-layer electric heating blade; 39. Pressure sensor; 40. Laser sensor; 41. Temperature sensor; 42. Back plate collection bin; 43. Air-cooled fan; 44. Copper welding belt absorption device; 45. Glass collection bin; 46. Ceramic insulation board; 47. Support; 48. Infrared imager; 49. Discharge port; 50. Purification bag; 51. Ash hopper; 52. Pulse trigger device; 53. Bracket; 54. Purification box; 55. Burner; 56. Furnace shell; 57. Combustion chamber; 58. Activated carbon adsorption net; 59. Photosensor. DETAILED DESCRIPTION

[0056] The specific contents of the present invention are further explained in detail below with reference to the embodiments.

[0057] like Figure 1 As shown, an intelligent device for sorting waste photovoltaic modules and recycling silicon wafers includes a box removal device 1, a frame removal mechanism 2, a sorting device 3, a hot knife device 4, a tunnel kiln 5, a screening device 6, a silver extractor 7, a pulse dust collector 8, a TO furnace 9, an activated carbon adsorption box 10, an induced draft fan 11 and a main control unit;

[0058] like Figure 2 As shown, the box-removing device 1 includes a box-removing platform 15 and a three-axis truss manipulator. The three-axis truss manipulator includes a three-axis truss 12 and a group of manipulators 13 mounted on the three-axis truss 12. The displacement of the manipulator 13 in the X, Y and Z directions is controlled by the three-axis truss 12. The end effector of the manipulator 13 is a scraper 14. The blades of the two scrapers 14 are arranged facing each other. The manipulator 13 is located above the box-removing platform 15, and the three-axis truss manipulator is connected to the main control unit.

[0059] The width of the box-taking platform 15 is greater than the width of the conveyor belt, and the box-taking platform 15 is provided with a groove for the conveyor belt to pass through. The plane where the conveyor belt is located coincides with the plane where the box-taking platform 15 is located. The waste photovoltaic component junction boxes to be recycled are transported face up via the conveyor belt to the bottom of the manipulator 13; a laser locator is provided on the three-axis truss 12, and the laser locator is connected to the main control unit. Since the distance from the junction box to the laser locator is smaller than the distance from other positions of the photovoltaic panel to the laser locator, different junction boxes are located by measuring the distance from the laser locator to the junction box. When the laser locator is When the distance from the optical locator to the junction box is the same as the set distance, the main control unit controls the conveyor belt to stop transmission according to the signal uploaded by the laser locator, and drives the manipulator 13 to move along the three-axis truss 12 to the top of the waste photovoltaic module junction box and move downward. The two scrapers 14 move towards each other to remove the junction box. Then the manipulator 13 drives the scrapers 14 to move upward, so that the junction box under the scraping moves upward together, so that the junction box is separated from the photovoltaic panel. Then the manipulator 13 drives the scrapers 14 to move forward and backward, and puts the junction box into the storage box located on the side of the box removal platform 15.

[0060] like Figure 3 As shown, the frame removal mechanism 2 includes a mounting frame 16 and a support platform 17. The width of the support platform 17 is greater than the width of the conveyor belt, and the support platform 17 is provided with a groove for the conveyor belt to pass through. The plane where the conveyor belt is located coincides with the plane where the support platform 17 is located. A light source is installed on the support platform 17, and a photosensitive sensor 59 is installed on the mounting frame 16, which is directly opposite to the light source. The photosensitive sensor 59 is connected to the main control unit.

[0061] A hydraulic power head 18 is fixedly installed in the middle of the mounting frame 16, and the hydraulic power head 18 is connected to the main control unit. A mounting plate 19 is fixedly installed below the hydraulic power head 18, and a tightening spring 20 is fixedly installed below the mounting plate 19. The lower end of the tightening spring 20 is fixedly connected to a pressing plate 22. Four obliquely arranged mounting rods are hinged around the mounting plate 19, and a return spring is fixedly connected between each adjacent two mounting rods. A push rod 21 perpendicular to the mounting rod is fixedly installed at the lower end of the mounting rod. The length of the push rod 21 can be designed according to the different sizes of photovoltaic panels on the market so as to remove the aluminum frame.

[0062] When the photovoltaic panel is conveyed to the bottom of the photosensor 59 by the conveyor belt, the photovoltaic panel blocks the light source, and the photosensor 59 cannot detect the light source signal. The main control unit drives the hydraulic power head 18 to move downward and push the mounting plate 19, so that the pressing plate 22 is pressed against the surface of the photovoltaic panel. The downward pressure is continued, and the push rod 21 pushes the aluminum frame outward. The reset spring is in a stretched state until it is removed. Then the hydraulic power head 18 moves upward and no longer applies downward thrust to the mounting rod. The elastic restoring force of the reset spring drives the four mounting rods to gather together.

[0063] like Figure 1 and 4 As shown, the sorting device 3 includes a support frame, on which an annular infrared light source 24 is fixedly mounted, and below the annular infrared light source 24 a high-resolution area array camera 23 is fixedly mounted. The area array camera 23 is connected to a telecentric lens 25 via a C-Mount interface, and the telecentric lens 25 is connected to the main control unit. When the photovoltaic panel with the frame removed is transported to the bottom of the annular infrared light source 24 via a conveyor belt, the annular infrared light source 24 is illuminated with a duty cycle of 80%, and the high-resolution area array camera 23 triggers shooting with an exposure time of 0.5ms. The telecentric lens 25 converts the transmitted light signal into a digital image signal with an image distortion rate of 0.01% to 0.03%. The digital image signal is input to the main control unit, and the industrial-grade embedded computing unit of the main control unit is deployed with a ResNet-18 model; as shown Figure 14 As shown in the figure, after Gaussian filtering and histogram equalization, the digital image is used as the input of the ResNet-18 model. Because the glass crack causes the local infrared signal transmittance to drop sharply from over 85% to below 70%, the industrial-grade embedded computing unit can calculate the crack probability value based on the transmittance. If the crack probability value of three consecutive frames is ≥0.98, the photovoltaic module is judged as a broken photovoltaic module; otherwise, the photovoltaic module is judged as a complete photovoltaic module.

[0064] Preferably, the model of the area array camera 23 is Basler ace 2Pro, and the area array camera 23 is fixedly installed directly above the conveyor belt through an aluminum alloy support frame;

[0065] Preferably, the wavelength of the annular infrared light source 24 is 850±10 nm, and the annular infrared light source 24 is coaxially sleeved on the periphery of the high-resolution area array camera 23 through a three-point cantilever adjustable bracket;

[0066] Preferably, the depth of field of the telecentric lens 25 is 15 mm;

[0067] like Figure 1 and Figure 5 As shown, the sorting device 3 further includes a pneumatic push rod 26, which is connected to the main control unit. The pneumatic push rod 26 is located on one side of the conveyor belt, and an inclined diversion pipe 30 is provided on the other side of the conveyor belt. One end of the diversion pipe 30 is connected to the feed pipe of the tunnel kiln 5. When the photovoltaic module is determined to be a broken photovoltaic module, it is conveyed forward by the conveyor belt to the diversion pipe 30. The main control unit drives the pneumatic push rod 26 to push the broken photovoltaic module into the diversion pipe 30.

[0068] Preferably, the pneumatic push rod 26 has a thrust of 600-1000N and a response time of 20-100ms, and a polyurethane buffer head is provided at the end thereof;

[0069] Compared to existing sorting technologies for retired photovoltaic modules, the sorting device 3 of this embodiment relies on infrared signal transmittance to sort photovoltaic modules. The ResNet-18 model requires a small amount of training data and low demand for computing resources. In addition, the pneumatic push rod 26 is used in conjunction with the diversion pipe 30 to separate the broken photovoltaic modules, resulting in a simple structure and low maintenance costs.

[0070] like Figure 1 、 Figure 6 and Figure 7 As shown, the hot knife device 4 includes a shell and a support 47 fixedly installed inside the shell and two sets of transmission rollers 36. A gap is left between the two sets of transmission rollers 36 to form a feed port 34. The conveyor belt 35 passes through the gap and is aligned with the conveyor belt at the tail end of the sorting device 3. The conveyor belt transports the complete photovoltaic component to the conveyor belt 35. When the complete photovoltaic component is located between the two sets of transmission rollers 36, the two sets of transmission rollers 36 clamp the complete photovoltaic component to prevent it from shifting on the conveyor belt 35. A pressure sensor 39 is embedded on the surface of the transmission roller 36 for measuring the pressure of the transmission roller 36 on the surface of the complete photovoltaic component. The pressure sensor 39 is connected to the main control unit; the support 47 is equipped with a double-layer electric heating knife head 38 and a laser sensor 40. The double-layer electric heating knife head 38 is made of high thermal conductivity material. The double-layer electric heating knife head 38 is connected to the heating device and is fixedly installed. There is a temperature sensor 41. The heating device and the temperature sensor 41 are both connected to the main control unit. The main control unit controls the heating power of the heating device according to the signal uploaded by the temperature sensor 41, so that the temperature of the double-layer electric heating blade 38 is maintained at 200-300°C to avoid damaging the silicon wafer during the softening of the EVA film and the copper welding tape. In the process of the conveyor belt 35 transporting the complete photovoltaic module forward, the double-layer electric heating blade 38 softens the EVA film between the upper glass and the silicon wafer and between the silicon cell and the back plate, thereby smoothly separating the upper glass and the lower back plate from the middle silicon cell. At the same time, the laser sensor 40 is used to position the copper welding tape. The main control unit controls the double-layer electric heating blade 40 to contact the copper welding tape and perform local heating according to the signal uploaded by the laser sensor 40. The heating time is 5-10 seconds, so that the softened copper welding tape is separated from the silicon cell.

[0071] The discharge port 49 of the hot knife device 4 is connected to the silver extractor 7 via a conveyor belt. The silicon cell is transported to the inside of the silver extractor 7 via a conveyor belt 35 to extract the silver electrode to obtain the silicon wafer.

[0072] The support 47 is equipped with a pair of ceramic insulation plates 46 made of ceramic material with low thermal conductivity. The drive roller 36, the conveyor belt 35 and the double-layer electric heating blade head 38 are located between the pair of ceramic insulation plates 46. The ceramic insulation plates 46 can reduce heat loss and maintain a relatively stable temperature. The top of the support 47 is slidably connected to a linear motor that can slide along it. The linear motor is connected to the main control unit. The output shaft of the linear motor is fixedly equipped with a connecting rod. The lower end of the connecting rod is fixedly connected to a vacuum suction cup 37. When the double-layer electric heating blade head 38 cuts into the upper glass, the lower back plate and the middle silicon battery cell, the main control unit starts the linear motor to drive the vacuum suction cup 37 to descend until it is stably adsorbed on the surface of the upper glass. The vacuum suction cup 37 is made of flexible material and can fit tightly to the glass surface to ensure the stability and reliability of the adsorption process.

[0073] The support 47 is equipped with a backboard collection bin 42 and a glass collection bin 45. The backboard collection bin 42 is located behind and below the transmission roller 36. The separated backboard falls into the backboard collection bin 42 under the action of gravity. The glass collection bin 45 is located on the side of the transmission roller 36. The linear motor moves along the support 47 and drives the vacuum suction cup 37 to move, thereby placing the glass into the glass collection bin 45.

[0074] The tail end of the support 47 is equipped with an air-cooling fan 43 and a copper soldering strip absorption device 44 in opposite positions, and an infrared imager 48 is fixedly installed on the top of the air-cooling fan 43. The infrared imager 48 is connected to the main control unit. The infrared imager 48 monitors the temperature of the silicon cell in real time and transmits the temperature to the main control unit. The main control unit adjusts the wind speed according to the temperature signal to quickly cool the copper soldering strip. At the same time, under the action of air blowing, the copper soldering strip is blown and stored in the copper soldering strip absorption device 44.

[0075] The support 47 supports the entire hot knife device 4, supporting the weight of the device and ensuring stability and safety during operation. The support 47 must have sufficient strength to withstand dynamic loads and adapt to different installation environments to prevent damage due to uneven ground or corrosive substances.

[0076] like Figure 1 and Figure 11As shown, the lower end of the guide pipe 30 is connected to the feed port of the tunnel kiln 5. After the crushed photovoltaic modules are pushed into the guide pipe 30, they enter the tunnel kiln 5 along the guide pipe 30. The interior of the tunnel kiln 5 is divided into a preheating zone 27, a core reaction zone 28 and a cooling zone 29 from front to back, and the preheating zone 27, the core reaction zone 28 and the cooling zone 29 are connected in sequence by conveyor belts, wherein: the preheating zone 27 is 10m long, lined with 310S stainless steel, and has a temperature range of 100-600°C; the core reaction zone 28 is 15m long, lined with silicon carbide ceramic The temperature range is 600-800°C, with the peak temperature maintained at 800±5°C. The conveyor belt residence time is 20 minutes. The core reaction zone 28 is connected to a temperature detector and an air conditioning device. The temperature detectors are K-type thermocouples installed inside the core reaction zone 28, with one set every 1 meter along the axial direction of the kiln body. They monitor the reaction temperature in real time and feed the temperature signal back to the main control unit. The air conditioning device includes an electric damper connected to the air supply duct of the core reaction zone 28, which is connected to the air inlet of the centrifugal fan installed outside the tunnel kiln 5. The main control unit dynamically adjusts the opening of the electric damper based on the feedback temperature signal, thereby regulating the oxygen content entering the core reaction zone, ensuring that the pyrolysis reaction proceeds at the optimal temperature and oxygen content. The pyrolysis reaction removes the EVA glue and backsheet from the broken photovoltaic modules. The cooling zone 29 is 8 meters long and equipped with a water-cooling jacket. The water inlet temperature of the water cooling jacket is 20°C, and the flow rate is adjustable between 2 and 10 m / s. 3 / h, lowering the discharge port temperature of tunnel kiln 5 to 80°C;

[0077] The core reaction zone 28 is provided with a smoke exhaust port, which is connected to the pulse dust collector 8 through a 316L stainless steel pipe;

[0078] Broken photovoltaic modules after unpacking and unframing. After the photovoltaic modules undergo pyrolysis inside the tunnel kiln 5 to remove the backsheet and EVA adhesive layer, there is no EVA adhesive layer between the glass and the silicon wafer, and the thin and long copper welding strips are separated from the fragmented silicon wafers. At the same time, the glass and silicon solar cells are pyrolyzed and shattered in the tunnel kiln 5. The high temperature causes uneven stress inside the glass, increasing cracks and making it easy to break into small particles. The silicon and metal components in the silicon solar cells make them more resistant to high temperatures and have strong toughness. The average diameter of the broken pieces is larger than the average diameter of the glass fragments, and the thin and long copper welding strips are separated from the fragmented solar cells.

[0079] The discharge port of the tunnel kiln 5 is connected to the feed port of the screening device 6 through a conveyor belt. The screening device 6 is a linear screen. The linear screen adopts a 304 stainless steel welded frame and has a vibration frequency range of 10 to 50 Hz. The upper screen 31 of the linear screen is made of 65Mn spring steel. Its screen holes are long strips, the screen hole size is 15 mm × 2 mm, the hole spacing between the screen holes is 5 mm, the dimensional error between the screen hole size and the hole spacing is 0.1 mm, the hole spacing is 5 ± 0.1 mm, and the diameter of the screen wire is 3 ± 0.05 mm, which is used to intercept silicon battery fragments; the lower screen 32 of the linear screen is made of 316L stainless steel, the screen holes are circular, the hole diameter is 5 ± 0.05 mm, the hole spacing is 3 ± 0.05 mm, and the screen wire diameter is 2 ± 0.05 mm, which is used to intercept copper welding strips. Glass fragments fall to the bottom through the screen holes;

[0080] The screening device 6 also includes a gas shock screening module, which includes a shock gas generator and an inert atmosphere gas supply bottle. The shock gas generator is fixedly mounted on the housing of the screening device 6 and is located between the upper screen 31 and the lower screen 32. The inert atmosphere gas supply bottle is connected to the shock gas generator through a gas pipeline. The inert atmosphere gas supply bottle supplies shock air to the shock gas generator, generating a pulsed high-pressure airflow between the upper screen 31 and the lower screen 32. Compared with the existing single vibration screening technology, the vibration-gas shock collaborative screening technology can shorten the screening time, improve the screening efficiency of the double-layer screen, screen materials in an inert atmosphere, and improve the recovery quality of each material.

[0081] The screening device 6 is connected to the collection system 33 through a conveyor belt. The collection system 33 includes a brazing belt collection box and a glass fragment collection box. The brazing belt collection box is located at the end outlet of the lower screen 32 and has a volume of 1m 3 The glass fragments collection box is located at the bottom of the screen body, with a capacity of 2m 3 ;

[0082] The mixed material at the discharge port of the tunnel kiln 5 is evenly spread to the top of the linear screen by a conveyor belt. The upper screen 31 intercepts the silicon solar cells under the action of vibration, and the mixture of copper welding strips and glass fragments enters the lower screen 32. The lower screen 32 intercepts the copper welding strips under the action of vibration. The copper welding strips are collected by the copper welding strip collection box, and the glass fragments pass through the lower screen 32 and are collected by the glass fragment collection box.

[0083] The end outlet of the upper screen 31 is connected to the silver extractor 7 via a conveyor belt. The silicon cell is conveyed to the silver extractor 7 via the conveyor belt to extract the silver electrodes from the silicon fragments. The silicon wafers obtained after silver extraction are discharged from the outlet of the silver extractor 7 and collected.

[0084] like Figure 1 and Figure 8As shown, the pulse dust collector 8 includes a bracket 53, on which a purification box 54 is fixedly mounted. An ash hopper 51 is fixedly connected to the lower part of the purification box 54. A dust collection box is provided below the ash hopper 51. A plurality of purification bags 50 are provided inside the purification box 54. The purification box 54 is connected to the exhaust port of the tunnel kiln 5 and the exhaust port of the hot knife device 4 through an air intake pipe. The exhaust gas enters the purification box 54 through the air intake channel and is filtered by the purification bag 50.

[0085] A pulse trigger device 52 is fixedly mounted on the purification box 54. The pulse trigger device 52 generates a pulse airflow to drop the dust in the purification bag 50 into the ash hopper 51. The dust in the ash hopper 51 falls into the dust collection box.

[0086] like Figure 1 and Figure 9 As shown, the top of the pulse dust collector 8 is connected to the TO furnace 9 through a pipeline. The TO furnace 9 includes a furnace shell 56. An independent combustion chamber 57 is provided inside the furnace shell 56. The combustion chamber 57 is equipped with a burner 55. The exhaust gas after dust removal enters the TO furnace 9 and first enters the furnace shell 56, then enters the combustion chamber 57 and is fully mixed with oxygen. It is oxidized and decomposed by the high temperature generated by the burner 55 when it is working, completing the expected purification treatment.

[0087] The outer wall of the combustion chamber 57 is provided with fins to enhance heat exchange and utilize the heat released during combustion in the combustion chamber 57 to preheat the exhaust gas entering the furnace shell 56;

[0088] The furnace shell 56 is further provided with a thermoelectric power generation chip, which is a single-stage semiconductor refrigeration chip, a double-stage semiconductor refrigeration chip, or a multi-stage semiconductor refrigeration chip. The hot end of the thermoelectric power generation chip is connected to the outer wall of the combustion chamber 57 through a flexible thermal conductive material, and the cold end of the thermoelectric power generation chip is connected to the furnace shell 56 through a flexible thermal conductive material. The temperature difference at both ends of the thermoelectric power generation chip is used to generate electricity. The generated DC electricity is boosted by a transformer and used for lighting the TO furnace 9.

[0089] The outer wall of the furnace shell 56 is equipped with a ceramic fiber insulation layer to reduce heat radiation from the hot end to the cold end. Compared with the existing exhaust gas treatment technology, the exhaust gas waste heat is used to generate electricity through the thermoelectric power generation chip, which plays a role in energy saving and efficiency improvement.

[0090] The gas outlet of the TO furnace 9 is connected to the activated carbon adsorption box 10 through a pipeline, and the gas after combustion and purification is connected to the activated carbon adsorption box 10 through a pipeline. Figure 10 , an activated carbon adsorption net 58 is provided inside the activated carbon adsorption box 10, and the activated carbon adsorption net 58 is used to adsorb and purify the gas after combustion purification;

[0091] The activated carbon adsorption net 58 is connected to the air inlet of the induced draft fan 11 through a pipeline. The negative pressure generated by the induced draft fan 11 drives the exhaust gas to enter the pulse dust collector 8, the TO furnace 9 and the activated carbon adsorption box 10 in sequence for purification treatment.

[0092] Preferably, the pulse dust collector 8, TO furnace 8 and activated carbon adsorption box 10 are connected in sequence through steel pipes. The pipeline steel is a seamless national standard steel pipe made of carbon steel, low alloy steel, stainless steel, etc. The steel pipe is connected to the pulse dust collector 8, TO furnace 8 and activated carbon adsorption box 10 through flanges. The flange connection can be achieved by flat welding, butt welding, socket welding and threaded flanges.

[0093] like Figure 1 、 Figure 12 and Figure 13 As shown, a method for intelligently sorting waste photovoltaic modules and recycling silicon wafers using the device as described in claim 2 comprises the following steps:

[0094] Step 1: The technicians put the complete set of waste photovoltaic modules into the process line, and remove the junction box and aluminum frame in turn through the box removal device 1 and the frame removal mechanism 2;

[0095] Step 2: The pre-treated waste photovoltaic modules are transported to the sorting device 3 via a conveyor belt. The annular infrared light source 24 is illuminated with a duty cycle of 80%. The infrared light emitted is transmitted through the photovoltaic modules to be sorted. The high-resolution area array camera 23 equipped with a telecentric lens 25 triggers the image capture. The telecentric lens 25 converts the transmitted infrared light signal into a digital image signal and transmits it to an industrial-grade embedded computing unit, which outputs a crack probability value. If the probability value for three consecutive frames is ≥0.98, the photovoltaic module is judged to be broken; otherwise, the photovoltaic module is judged to be intact.

[0096] Step 3: Recycling silicon wafers, glass and copper soldering tapes from discarded photovoltaic modules. The specific process is as follows:

[0097] When the photovoltaic module is judged to be a complete photovoltaic module, the main control unit drives the conveyor belt to convey the complete photovoltaic module to the conveyor belt 35. As the conveyor belt 35 runs, it enters the hot knife device 4 from the feed port 34. Then two sets of transmission rollers 36 firmly clamp it so that the photovoltaic panel will not be displaced during the disassembly process. The double-layer electric hot knife head 38 is started and preheated to 200-300°C. The hot knife head is slowly pushed along the laminated interface of the photovoltaic panel at a set pushing speed to soften the EVA film and separate the glass and back panel from the silicon cell. During the cutting process, the temperature, pushing speed and stress of the double-layer electric hot knife head 38 are monitored in real time through the data fed back by the temperature sensor 41, the laser sensor 40 and the pressure sensor 39. The operating parameters are automatically adjusted by the main control unit or appropriate human intervention is given to make the cutting process more accurate and stable. At the same time, the laser is used to The sensor 40 positions the double-layer electric heating blade 38 in contact with the copper soldering tape, locally heating it for 5 to 10 seconds to soften the connection between the copper soldering tape and the silicon wafer; the vacuum suction cup array 37 absorbs the peeled glass and moves it to the glass collection bin 45, and the backplane falls into the backplane collection bin 42 under the transmission roller 36. The copper soldering tape is attached to the silicon cell and is conveyed forward by the conveyor belt 35. The technician starts the air-cooling fan 43 to generate forced convection dry air to quickly reduce the temperature of the silicon cell. Under the blowing of the airflow, the softened copper soldering tape is completely peeled off from the silicon wafer and is blown into the copper soldering tape absorption device 44 opposite the air-cooling fan 43. The copper soldering tape, silicon cell and intact glass are recovered from the waste photovoltaic modules. The silicon cell is inspected by an infrared imager until it cools down to normal temperature. It is then conveyed to the silver extractor 7 via the conveyor belt 35 to extract the silver electrode to obtain high-purity silicon for the preparation of silicon-carbon negative electrode.

[0098] When a photovoltaic module is determined to be a broken photovoltaic module, the main control unit drives the conveyor belt to convey the broken photovoltaic module to the front of the pneumatic push rod 26, and the pneumatic push rod 26 pushes the broken photovoltaic module to the entrance of the inclined diversion pipe 30. The broken photovoltaic module enters the tunnel kiln 5 along the inclined diversion pipe 30 for pyrolysis reaction. The specific process is: the preheating zone 27 preheats the broken photovoltaic module in the temperature range of 100-600°C. The preheating temperature rises in a step-by-step manner to prevent the photovoltaic module from bursting due to excessive temperature changes. The preheated photovoltaic module enters the core reaction zone 28, is heated to 600-800°C and maintained for 20 minutes, and the EVA glue layer in the broken photovoltaic module is cracked at 600°C into CO2, H2O and short-chain hydrocarbons. The glass plate is broken into fragments with an average diameter of less than 5mm due to thermal stress, and the battery cell is broken into flaky particles with a diameter range of 10-20 mm, the copper welding strip is kept longer than 50 mm due to the difference in ductility. During this process, the K-type thermocouple feeds back the temperature inside the core reaction zone 28 to the main control unit in real time. The main control unit dynamically adjusts the oxygen content in the combustion zone according to the temperature to ensure that the photovoltaic module undergoes pyrolysis reaction under the conditions of optimal temperature and optimal oxygen content. The photovoltaic module after pyrolysis reaction is conveyed to the cooling belt 29 along the conveyor belt to reduce the temperature to below 80°C. The photovoltaic module after pyrolysis includes a mixture of silicon cell fragments, copper welding strips and glass. The mixture is conveyed to the screening device 6 by the conveyor belt. After vibration screening, the upper screen 31 intercepts the silicon cell fragments, and the silicon cell fragments are conveyed to the silver extractor 7 through the conveyor belt. The lower screen 32 intercepts the copper welding strips and collects the copper welding strips in the copper welding strip aggregate box in the aggregate system 33. The glass fragments are collected in the glass aggregate box in the aggregate system 33 through the lower screen 32.

[0099] The silicon cell fragments conveyed by the hot knife device 4 and the screening device 6 can be collected on the same conveyor belt and enter the same silver extractor 7 to extract the silver electrodes and obtain high-purity silicon wafers;

[0100] Step 4: Under the negative pressure generated by the induced draft fan 11, the organic waste gas generated during the operation of the hot knife device 4 and the tunnel kiln 5 is sent to the pulse dust collector 8. After the dust is filtered by the purification bag 50, the waste gas enters the TO furnace 9. The fins arranged on the outside of the combustion chamber 57 of the TO furnace 9 are used to enhance heat exchange, and the organic waste gas including VOCs is preheated to 700-800°C. It is oxidized and decomposed into carbon dioxide and water vapor at high temperature, and the gas generated in the TO furnace 9 is passed into the activated carbon adsorption box 10 to remove residual pollutants.

[0101] This embodiment can intelligently sort out complete photovoltaic modules and broken photovoltaic modules, and adopts the hot knife device 4 and the tunnel kiln 5 to separate the silicon cells, copper welding strips and glass in the complete photovoltaic modules and the broken photovoltaic modules respectively. Compared with the uniform pyrolysis treatment of photovoltaic modules, the emission of pollutants is reduced, the intelligent sorting and targeted recycling of photovoltaic modules are realized, and the recycling quality and economic value of photovoltaic modules are improved. At the same time, the waste discharged by the knife device 4 and the tunnel kiln 5 is purified, further improving the environmental friendliness.

Claims

1. An intelligent device for sorting waste photovoltaic modules and recycling silicon wafers, characterized in that: It comprises a box taking device (1), a frame removing mechanism (2), a sorting device (3), a hot knife device (4), a tunnel kiln (5), a screening device (6), a silver extracting machine (7) and a general control unit; The box taking device (1), the frame removal mechanism (2), the sorting device (3) and the hot knife device (4) are connected in sequence through a conveyor belt. The sorting device (3) includes a support frame and a pneumatic push rod (26). An annular infrared light source (24) is fixedly installed on the support frame. An area array camera (23) is fixedly installed below the annular infrared light source (24). The area array camera (23) is connected to a telecentric lens (25) through a C-Mount interface. The telecentric lens (25) is connected to a general control unit. The general control unit is equipped with a ResNet-18 model. The pneumatic push rod (26) is installed on one side of the conveyor belt and connected to the general control unit. An inclined guide pipe (30) is provided on the other side of the conveyor belt. The guide pipe (30) is connected to the feed port of the tunnel kiln (5). The hot knife device (4) comprises a shell and a support (47) fixedly installed inside the shell and two sets of upper and lower transmission rollers (36), the support (47) is fixedly connected to a pair of ceramic heat insulation plates (46), the transmission rollers (36) are located between the pair of ceramic heat insulation plates (46), a gap is left between the upper and lower sets of transmission rollers (36), forming a feed port (34), the conveyor belt (35) passes through the gap and connects with the conveyor belt at the tail end of the sorting device (3), and a pressure sensor (39) is fixedly embedded on the surface of the transmission roller (36); a movable and retractable connecting rod is installed on the top of the support (47), and a vacuum suction cup (37) is fixedly connected to the lower end of the connecting rod; a double-layer electric heating knife head (38) and a laser sensor (40) are installed below the support (47), the double-layer electric heating knife head (38) is connected to the heating device and fixedly installed with a temperature sensor (41), and the pressure sensor (39), the laser sensor (40), the heating device and the temperature sensor (41) are all connected to the main control unit; The support (47) is further equipped with a back plate collection bin (42) and a glass collection bin (45), as well as an air-cooling fan (43) and a brazing strip absorption device (44) located opposite to each other, wherein: the back plate collection bin (42) is located at the rear and lower part of the transmission roller (36), the glass collection bin (45) is located at the side of the transmission roller (36), and an infrared imager (48) for measuring temperature connected to the main control unit is installed on the top of the air-cooling fan (43); The discharge port of the tunnel kiln (5) is connected to a screening device (6) via a conveyor belt. The screening device (6) comprises an upper screen (31) for intercepting silicon cell fragments and a lower screen (32) for intercepting copper welding strips. The terminal outlet of the upper screen (31) is connected to a silver extractor (7) via a conveyor belt. The silver extractor (7) is also connected to the discharge port of the hot knife device (4) via a conveyor belt.

2. The intelligent sorting and recycling equipment for waste photovoltaic modules and silicon wafers according to claim 1 is characterized in that: It also includes a pulse dust collector (8), a TO furnace (9), an activated carbon adsorption box (10) and an induced draft fan (11) which are sequentially connected through pipelines; The hot knife device (4) and the smoke exhaust port of the tunnel kiln (5) are both connected to the pulse dust collector (8) through a pipeline.

3. The intelligent sorting and recycling equipment for waste photovoltaic modules and silicon wafers according to claim 2 is characterized in that: The box-taking device (1) comprises a box-taking platform (15) and a three-axis truss manipulator. The width of the box-taking platform (15) is greater than the width of the conveyor belt. The box-taking platform (15) is provided with a groove for the conveyor belt to pass through. The plane where the conveyor belt is located coincides with the plane where the box-taking platform (15) is located. The three-axis truss manipulator is connected to a general control unit and comprises a manipulator (13) and a three-axis truss (12) for controlling the manipulator (13) to move along the X, Y and Z directions. The manipulator (13) is located above a box-taking platform (15), and the end effector of the manipulator (13) is a scraper (14), and the blades of the two scrapers (14) are arranged facing each other.

4. The intelligent sorting and recycling equipment for waste photovoltaic modules and silicon wafers according to claim 2 or 3, characterized in that: The frame removal mechanism (2) includes a mounting frame (16) and a support platform (17). The width of the support platform (17) is greater than the width of the conveyor belt, and the support platform (17) is provided with a groove for the conveyor belt to pass through. The plane where the conveyor belt is located coincides with the plane where the support platform (17) is located. A light source is installed on the support platform (17). The mounting frame (16) is provided with a photosensitive sensor (59) that is directly opposite to the position of the light source. The photosensitive sensor (59) is connected to the main control unit. The mounting frame (16) is also fixedly mounted with a hydraulic power head (18) connected to the general control unit, a mounting plate (19) is fixedly mounted below the hydraulic power head (18), a pressing spring (20) is fixedly mounted below the mounting plate (19), a pressing plate (22) is fixedly connected to the lower end of the pressing spring (20), and four obliquely arranged mounting rods are hinged around the mounting plate (19), a reset spring is fixedly connected between each two adjacent mounting rods, and a push rod (21) perpendicular to the mounting rod is fixedly mounted at the lower end of the mounting rod.

5. The intelligent sorting and recycling equipment for waste photovoltaic modules and silicon wafers according to any one of claims 1 to 3, characterized in that: The tunnel kiln (5) comprises a preheating zone (27), a core reaction zone (28) and a cooling zone (29) which are sequentially connected by a conveyor belt, wherein: The preheating zone (27) is lined with 310S stainless steel, and the temperature range is 100-600°C; the core reaction zone (28) is lined with silicon carbide ceramics, and the temperature range is 600-800°C, and the core reaction zone (28) is connected to a temperature detector and an air conditioning device; the cooling zone (29) is provided with a water cooling jacket, and the water inlet temperature of the water cooling jacket is 20°C; The temperature detectors are K-type thermocouples arranged at intervals of 1 m along the axial direction of the tunnel kiln (5), and the K-type thermocouples are connected to a general control unit; the air conditioning device comprises an electric air valve connected to an air supply duct of the core reaction zone (28), and the electric air valve is connected to an air inlet of a centrifugal fan arranged outside the tunnel kiln (5).

6. The intelligent sorting and recycling equipment for waste photovoltaic modules and silicon wafers according to any one of claims 1 to 3, characterized in that: The screening device (6) further includes an air oscillation screening module, which includes an oscillation gas generator and an inert atmosphere gas supply bottle. The oscillation gas generator is located between the upper screen (31) and the lower screen (32). The inert atmosphere gas supply bottle provides an oscillating inert atmosphere for the oscillation gas generator, thereby forming a pulsed high-pressure airflow between the upper screen (31) and the lower screen (32).

7. The intelligent sorting and recycling equipment for waste photovoltaic modules and silicon wafers according to any one of claims 1 to 3, characterized in that: The screening device (6) is connected to a collection system (33) via a conveyor belt. The collection system (33) comprises a brazing belt collection box located at the end outlet of the lower screen (32) and a glass fragment collection box located at the bottom of the lower screen (32).

8. The intelligent sorting and recycling equipment for waste photovoltaic modules and silicon wafers according to claim 2 or 3, characterized in that: The pulse dust collector (8) includes a bracket (53), a purification box (54) is fixedly mounted on the bracket (53), a pulse trigger device (52) is fixedly mounted on the purification box (54), an ash hopper (51) is fixedly connected to the lower part of the purification box (54), and a dust collection box is provided below the ash hopper (51); A plurality of purification bags (50) are arranged inside the purification box (54), and the purification box (54) is connected to the smoke exhaust ports of the tunnel kiln (5) and the hot knife device (4) through pipelines.

9. The intelligent sorting and recycling equipment for waste photovoltaic modules and silicon wafers according to claim 2 or 3, characterized in that: The TO furnace (9) includes a furnace shell (56), an independent combustion chamber (57) is provided inside the furnace shell (56), a burner (55) is installed at the end of the combustion chamber (57), and fins are arranged on the outer wall of the combustion chamber (57); A ceramic fiber insulation layer is fixedly installed on the outer wall of the furnace shell (56), and a thermoelectric power generation chip is also provided inside the furnace shell (56). The hot end of the thermoelectric power generation chip is connected to the outer wall of the combustion chamber (57) through a flexible heat-conducting material, and the cold end of the thermoelectric power generation chip is connected to the furnace shell (56) through a flexible heat-conducting material. Power is generated by the temperature difference between the hot end and the cold end of the thermoelectric power generation chip.

10. A method for intelligently sorting waste photovoltaic modules and recycling silicon wafers using the device as claimed in claim 2, characterized in that: The steps include: Step 1: Remove the junction box and aluminum frame of the waste photovoltaic module in sequence through the box removal device (1) and the frame removal mechanism (2), and convey the waste photovoltaic module with the junction box and aluminum frame removed to the sorting device (3) through the conveyor belt; Step 2: The annular infrared light source (24) is lit with a duty cycle of 80%, and the infrared light emitted is transmitted through the photovoltaic module to be sorted. The high-resolution area array camera (23) equipped with a telecentric lens (25) triggers the shooting. The telecentric lens (25) converts the transmitted infrared light signal into a digital image signal, which is used as the input of the ResNet-18 model deployed in the main control unit. The crack probability value is calculated based on the output of the ResNet-18 model. When the probability value of three consecutive frames is ≥0.98, the main control unit determines that the photovoltaic module is a broken photovoltaic module; otherwise, the photovoltaic module is determined to be a complete photovoltaic module. Step 3: Recycling silicon wafers, glass and copper soldering tapes from discarded photovoltaic modules. The specific process is as follows: When the photovoltaic module is judged to be a complete photovoltaic module, the main control unit drives the conveyor belt to convey the complete photovoltaic module to the conveyor belt (35). As the conveyor belt (35) runs, it enters the hot knife device (4) from the feed port (34). Then, two sets of transmission rollers (36) firmly clamp it, start the double-layer electric hot knife head (38), preheat the double-layer hot knife head (38) to 200-300°C, and slowly advance the hot knife head along the laminated interface of the photovoltaic panel at a set advancement speed to soften the EVA film and separate the glass and backboard from the silicon cell. During the cutting process, the temperature, advancement speed and force of the double-layer electric hot knife head (38) are monitored in real time through the data fed back by the temperature sensor (41), the laser sensor (40) and the pressure sensor (39). The operating parameters are automatically adjusted by the main control unit or appropriate human intervention is given. Operation intervention; at the same time, a laser sensor (40) is used to position the double-layer electric heating blade (38) in contact with the copper soldering tape, and local heating is performed for 5 to 10 seconds to soften the connection between the copper soldering tape and the silicon wafer; the vacuum suction cup array (37) absorbs the peeled glass and moves it to the glass collection bin (45), and the backplane falls into the backplane collection bin (42) below the transmission roller (36). The copper soldering tape is attached to the silicon cell and is transported forward by the conveyor belt (35). The air-cooling fan (43) is started to generate forced convection dry air, and the copper soldering tape is completely peeled off from the silicon wafer and blown into the copper soldering tape absorption device (44) by air. The copper soldering tape, silicon cell and complete glass in the recycled photovoltaic module are detected by the infrared imager (48). When the temperature of the silicon cell drops to room temperature, it is transported to the silver extractor (7) via the conveyor belt (35); When the photovoltaic module is determined to be a broken photovoltaic module, the main control unit drives the conveyor belt to convey the broken photovoltaic module to the front of the pneumatic push rod (26), and the pneumatic push rod (26) pushes the broken photovoltaic module to the entrance of the inclined diversion pipe (30). The broken photovoltaic module enters the tunnel kiln (5) along the inclined diversion pipe (30) for pyrolysis reaction, and undergoes preheating, pyrolysis and cooling in the tunnel kiln (5) in sequence to remove the EVA adhesive layer and the back plate to obtain a mixture of silicon cell fragments, copper welding tape and glass, wherein: the preheating temperature is The temperature is 100-600°C, the pyrolysis temperature is 600-800°C, and the pyrolysis time is 20 minutes. During the pyrolysis process, the oxygen content in the combustion zone is dynamically adjusted according to the real-time temperature. The cooled silicon battery fragments, the brazing strips and the glass mixture are transported to a screening device (6) via a conveyor belt. After vibratory screening, the upper screen (31) intercepts the silicon battery fragments, which are then transported to a silver extractor (7) via a conveyor belt. The lower screen (32) intercepts the brazing strips and the separated glass fragments and collects them separately. A silver extraction machine (7) is used to extract the silver electrode sheet from the silicon cell sheet to obtain a high-purity silicon sheet; Step 4: Under the negative pressure generated by the induced draft fan (11), the organic waste gas generated during the operation of the hot knife device (4) and the tunnel kiln (5) is sequentially sent to the pulse dust collector (8), the TO furnace (9) and the activated carbon adsorption box (10), and the pollution in the waste gas is removed through dust removal, thermal decomposition and adsorption.

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