Method for recycling a photovoltaic module and system used in the method

Abstract

Method for recycling a photovoltaic module and system used in the method. A recycling method and system for a photovoltaic module are disclosed. The photovoltaic module includes a battery component, glass, a frame, and a junction box. The recycling method includes the following steps: identifying frame sizes, positioning the frame and junction box, disassembling the junction box, removing the frame, removing the glass, breaking down the battery component under heating conditions to obtain a gaseous and a solid component, condensing the gaseous component to produce oil for use in the decomposition stage, and vibrating the solid component to distinguish the sizes and / or weights of different materials.

Description

Method for recycling a photovoltaic module and system used in the method Field of invention This application relates to a photovoltaic module, and more particularly to a recycling method for the photovoltaic module, as well as the system used in the same method. Background of the invention Photovoltaic modules have been widely used around the world, especially in areas with vast, open, rural regions. Due to the gradual depletion of existing energy sources caused by the excessive exploitation of natural resources, people are beginning to seek alternative solutions to this dilemma. Devices that utilize hydropower and wind energy are constantly being developed in an attempt to reduce dependence on fossil fuels. Therefore, large dams and wind turbines are being built to generate green energy for the benefit of humanity. However, another alternative solution to reduce fossil fuel use is to use solar energy to continuously generate clean and unlimited energy. Because solar energy is clean and a reusable energy source, and doesn't require the high costs of dams or wind turbines, solar energy devices and modules are increasingly popular today. To address the growing trend of using solar energy as the primary clean / green alternative energy source, users are making every effort to build as many solar power plants as possible. As is known, a solar power plant consists of a set of photovoltaic modules, which primarily comprise a silicon-based battery, an organic film mounted or permanently attached on top of the silicon-based battery, a glass panel mounted on top of the organic film, a frame enclosing the silicon-based battery, the organic film, and the glass, and a junction box attached to one side of the frame. Furthermore, once the photovoltaic module is activated, it is installed in an open area exposed to all kinds of environmental factors, including, but not limited to, wind, rain, and sunlight.Under such circumstances, the photovoltaic module gradually ages, causing the organic film to yellow. Consequently, the energy transfer rate of the silicon-based battery deteriorates. As a result of this deterioration, the photovoltaic module is then destined to be recycled and dismantled when it no longer meets the minimum energy transfer rate. When the photovoltaic module is dismantled, a variety of materials, such as the silver lines printed on one side of the battery or the organic film on top of the battery, can be collected, modified, and reused for various purposes. Currently, the recycling method for aged photovoltaic modules is divided into a dry method and a wet method. The dry method primarily relies on a furnace filled with shredded photovoltaic modules to achieve the recycling process. The wet method uses an acidic solution to separate the organic film from the glass, thus recycling the glass and the organic film separately. When using the dry method, the output is a mixture of shredded glass and silicon fragments. Sieving and separating the different materials from the mixture requires significant additional time and effort, and a large amount of waste is generated during the separation process, making it unprofitable. The wet method takes approximately one week to complete. However, the disposal of the used acidic solution still poses environmental problems. Due to concerns about current recycling technology, it is urgent to develop a new recycling technology that is faster, easier, and more cost-effective. Summary of the invention The main objective of this disclosure is to provide a method for recycling a photovoltaic module that includes a battery component, glass, a frame, and a junction box. The method comprises the following steps: remove the frame and the glass; break down the battery component under heating conditions to have a gaseous part and a solid part; condense the gaseous part to feed the shredding stage; and vibrate the solid part based on the sizes and / or weight of different materials. A different disclosure objective is that the battery component consists of an encapsulation film and a battery component having the encapsulation film permanently applied on top of the battery component. A different objective of the disclosure is to use a visual aid device to identify the frame size and position the frame. A different disclosure objective is that the visual aid device be a CCD device. A different objective of the disclosure is to have the glass crushed in situ after removal. A different disclosure objective is that before removing the glass, the glass, as well as the battery component, is preheated to decrease the adhesion resistance between the glass and the encapsulation film. A different objective of disclosure is to provide an anaerobic environment in the battery component shredding stage. A different objective of the disclosure is that the temperature in the anaerobic environment is 300~450 ºC. A different objective of the disclosure is that after breaking down the battery component into pieces, the size of the pieces is less than 5 cm×5 cm. A different disclosure objective is that the preheating temperature for the battery component be no less than 120°C. A different disclosure objective is that before removing the glass, the glass, as well as the battery component, are preheated to decrease the adhesion resistance between the glass and the encapsulation film applied permanently on top of the battery component; the preheating temperature for the battery component is not less than 120°C. A different objective of the disclosure is that after the gaseous part condenses, bio-oil is obtained. A different disclosure objective is that after the battery component shredding stage, the solid part is composed of carbon black, silicon pieces, metal, and glass residue. A different objective of diffusion is to have an agitation stage mixed with the vibration stage to divide the materials into large mass and small mass. A different objective of the disclosure is that the method includes a stage of identifying frame sizes and positioning the frame. A recycling system for a photovoltaic module having a battery component, glass, a frame, and a junction box comprises an anaerobic oven to provide an anaerobic environment; and vibrating elements and screens to distinguish the sizes and / or weight of different materials conveyed from the anaerobic oven. A different objective of the disclosure is that the system also includes a visual aid device to identify the frame size and position the frame. A different objective of the disclosure is that the system also includes robotic arms to remove the junction box, frame, and glass. A different disclosure objective is that the system also includes robotic arms to remove the junction box, frame and glass, and conveyor belts to transport the battery component after it has been shredded to and from the anaerobic oven. A different objective of the disclosure is that the system also includes a condenser to condense the different materials outside the anaerobic oven. A different disclosure objective is that the condenser is a slag cooler and / or a condensation device. Brief description of the attached drawings N / A Detailed description of the invention The preferred embodiment of the present invention relates to a recycling method for a photovoltaic module comprising a backboard, a silicon-based battery mounted on one side of the backboard, an organic film fixedly mounted on free sides of the battery to enclose the battery, a glass mounted on one or two opposite sides of the organic film, a frame fixedly mounted on sides of the glass to fix the position of the glass, and a mixture of the organic film and the battery on top of the backboard. When a photovoltaic module begins to show signs of aging, it is necessary to replace the aging module with a new one. The replaced or obsolete photovoltaic module is then sent to a recycling plant for off-site recycling, or, in some embodiments, the replaced photovoltaic module is recycled at a location where the recycling plant is situated (in-situ). It should be noted that in the detailed description of the preferred embodiment of the present invention below, no emphasis will be placed on whether the steps or measures taken in the preferred embodiment are performed in-situ or off-site because each step of the preferred embodiment of the present invention thus implied can be performed in either manner.In other words, the device or module involved in carrying out the preferred embodiment of the present invention can be manufactured to be small, portable, and lightweight in order to meet the requirement of being easily and quickly transported to the necessary location. On the other hand, considering various circumstances, some of the devices involved can be manufactured to be large and heavy in order to meet the high volume of recycling demands. The method for recycling a photovoltaic module, which has a battery component, glass, a frame, and a junction box, involved in the preferred embodiment of the present invention includes the following steps: remove the junction box, frame and glass; break down the battery component under heating conditions to have a gaseous part and a solid part; condense the gaseous part to feed the shredding stage; and vibrate the solid part based on the sizes and / or weight of different materials. In some embodiments, a visual aid device, such as a CCD, is used to identify the frame size and position it. The junction box is also blocked by the visual aid device. Robotic arms are then used to remove the junction box and frame. To facilitate glass removal, the photovoltaic module, with the junction box and frame removed, is preheated to at least 120°C to reduce the adhesion between the battery component and the glass. This decreases the adhesion of an organic film permanently applied over the battery to the glass. After the adhesion between the glass and the battery component has been reduced, the glass is removed from the battery component and crushed either on-site or off-site for collection.It is worth noting that the glass can be applied to one side or two opposite sides of the battery component depending on the different requirements. After the casing and glass are removed, an anaerobic environment, i.e., an anaerobic furnace, is heated to an internal temperature ranging from 300 to 450 °C. The battery component, consisting of a silicon-based battery and a backplate permanently attached to the bottom of the battery opposite an encapsulation film on top, is first broken down into pieces smaller than 5 cm × 5 cm and fed into the anaerobic furnace using, for example, a conveyor belt or commercially available conveyors. The purpose of placing the battery component inside the anaerobic furnace is to incinerate both the organic and inorganic materials within the furnace. When the organic and inorganic materials carried by the battery component are incinerated inside the anaerobic furnace, the resulting product will be both gaseous and solid.The macromolecules within the organic film on top of the battery break down to form pyrolysis gas and carbon black. As for the inorganic material, after incineration, it is first cooled, using a device such as a slag cooler or condenser, to a temperature of 75°C or lower. The pyrolysis gas is then condensed to form bio-oil for collection and / or recyclable fuel, which is fed back into the anaerobic furnace. The solid portion can then be separated into carbon black, metal, silicon fragments, and perhaps some glass residue that was originally left on the organic film surfaces. When the solid fraction is produced in the anaerobic furnace, several sieves, each fitted with different mesh sizes, are used to separate particles of varying sizes. For example, metals such as copper, due to their mass and large size, are first sieved and collected. The remaining material is reprocessed to produce silicon fragments and ash slag. This output also contains a mixture of powder. During the process for the silicon fragments, ash slag, and powder mixture, vibratory elements and conveyor belts are used, and sieves of different sizes are positioned appropriately so that the powder mixture, with the smallest particle size, exits at one end, and the silicon fragments and ash slag exit at the other. The powder mixture is sieved again by vibration and / or agitation via conveyor belts to obtain carbon black and silicon mixture. The silicon particles and ash slag, as well as the silicon mixture, are then passed through vibration and / or agitation, respectively, to obtain a final product: ash slag and silica powder slag.

Claims

1. A method for recycling a photovoltaic module comprising a battery component, glass, a frame, and a junction box, comprising the steps of: disassembling the junction box; removing the frame and glass; crumbling the battery component under heating conditions to obtain a gaseous and a solid portion; condensing the gaseous portion to feed into the crumbling stage; and vibrating the solid portion based on the sizes and / or weight of the different materials.

2. The method of claim 1, wherein the battery component comprises a battery and a backplate fixed to one side of the battery.

3. The method of claim 1, wherein a visual aid device is used to identify the size of the frame and position the frame.

4. The method of claim 3, wherein the visual aid device is a CCD device. 5.Method according to claim 3, wherein the glass is crushed in situ after removal.

6. Method according to claim 2, wherein prior to glass removal, the glass and the battery component are preheated to reduce the adhesion resistance between the glass and an encapsulation film permanently applied to one side of the battery component opposite the backplate.

7. Method according to claim 1, wherein an anaerobic environment is provided during the battery component crushing stage.

8. Method according to claim 7, wherein the temperature in the anaerobic environment is 300–450 °C.

9. Method according to claim 7, wherein after crushing the battery component to produce pieces, the size of the pieces is less than 5 cm × 5 cm.

10. Method according to claim 6, wherein the preheating temperature for the battery component is not less than 120 °C. 11.A method according to claim 8, wherein, prior to glass removal, the glass and the battery component are preheated to reduce the adhesion resistance between the glass and an encapsulation film permanently applied to one side of the battery component opposite the back panel, the preheating temperature for the battery component being not less than 120°C.

12. A method according to claim 8, wherein the gaseous portion is condensed to obtain bio-oil.

13. A method according to claim 8, wherein, after the battery component shredding stage, the solid portion consists of carbon black, silicon fragments, metal, and glass residue.

14. A method according to claim 7, wherein the stirring stage is combined with the vibration stage to separate the materials into large and small masses. 15.Method according to claim 7, further comprising a step of identifying the frame sizes and positioning the frame.

16. Recycling system for a photovoltaic module having a battery component, glass, a frame, and a junction box, the system comprising: an anaerobic oven for providing an anaerobic environment having a temperature ranging from 300 to 450 °C; and vibrating elements and screens for distinguishing the sizes and / or weight of different materials conveyed from the anaerobic oven.

17. System according to claim 16, further comprising a visual aid device for identifying the frame size and positioning the frame.

18. System according to claim 16, further comprising robotic arms for removing the junction box, the frame, and the glass. 19.A system according to claim 17, further comprising robotic arms for removing the junction box, frame, and glass, and conveyor belts for transporting the shredded battery component to and from the anaerobic furnace.

20. A system according to claim 16, further comprising a condenser for condensing the different materials outside the anaerobic furnace.

21. A system according to claim 20, wherein the condenser is a slag cooler and / or a condensation device.