TWI682555B - Recovery method of solar cell module (1) - Google Patents

Abstract

The invention provides a method for recycling a solar cell module. The solar cell module includes a solar cell panel, a cover plate provided on one surface of the solar cell panel, and a cover plate provided on the solar cell panel to reverse the cover plate The back sheet on the other surface of the two, and two are sandwiched between the solar panel and the cover panel, and the adhesive layer between the solar panel and the back panel. The method includes a first disassembling step and a second disassembling step. The first disassembling step utilizes the solar module in a non-polar solvent under the condition of pressure between 1~5Kg/cm ² Next, the solar panel is separated from the back sheet to obtain a first dismantling object. The second disassembling step places the first dismantling object in a water vapor environment with a temperature of not less than 100°C or a non-polar solvent. In at least one, the cover plate is separated from the solar cell panel.

Description

Recovery method of solar cell module (1)

The invention relates to a recycling method, in particular to a recycling method of a solar cell module.

Solar power generation is a kind of green energy, especially in modern times where energy is scarce, the development of solar power generation is an important technology. At present, solar cell modules that use photoelectric conversion to generate electrical energy have been quite popular and have a long service life. They are one of the green energy vigorously promoted by government agencies. However, although solar cell modules are a fairly environmentally friendly energy system, they contain a large number of Heavy metals, therefore, if the abandoned solar cell modules are discarded at will without relevant recycling procedures, it will cause serious environmental pollution.

At present, there are many ways to recover solar cell modules, such as high-temperature heat treatment, burning the adhesive layer (such as EVA, ethylene vinyl acetate) sandwiched between the back sheet and the glass plate, or using chemical solvents to remove EVA The adhesive layer dissolves, so that the back sheet and the glass sheet can be separated from the battery panel for the subsequent recycling process. However, when the solar cell module is decomposed by heat treatment, it is difficult to burn the EVA adhesive layer clean, and the temperature will be too high. As a result, the battery plate or the back plate is damaged, and the method of using a solvent to dissolve the EVA adhesive layer must subsequently deal with the solvent that dissolves the EVA adhesive layer, and the above method cannot recycle and reuse the EVA adhesive layer.

Therefore, the purpose of the present invention is to provide a method for recycling solar cell modules.

Therefore, the recycling method of the solar cell module of the present invention includes a first disassembly step and a second disassembly step.

The first disassembling step provides a solar module including a solar cell panel, a light-transmissive cover plate disposed on one surface of the solar cell, and a solar panel reverse the cover A back sheet on the other surface of the panel, and two sandwiched between the solar panel and the cover panel, and the glue layer between the solar panel and the back panel, placing the solar module in a non-polar solvent And, under the condition of pressure between 1~5Kg/cm ² , the solar cell panel and the back panel are separated to obtain a first dismantling object.

The second disassembling step is to place the first dismantling object in at least one of a water vapor environment with a temperature of not less than 100°C or a non-polar solvent to separate the cover plate from the solar cell panel.

The effect of the present invention is to use the conditions of non-polar solvent or non-polar steam and water vapor to make the glued layers can reduce the viscosity with different materials without dissolving, but can The separation and recycling of the glass plate and the solar cell panel, the overall recycling process is relatively simple and is beneficial to the subsequent recycling of the glued layers, so that the entire solar module can be recycled.

With reference to FIGS. 1 and 2, the method for recovering solar cell modules of the present invention is suitable for disassembling and recovering a solar module 2.

The solar module 2 includes a solar cell panel 21, a cover plate 22 disposed on one surface of the solar cell panel 21 and transmitting light, and another one disposed on the solar cell panel 21 to reverse the cover panel 22 The back sheet 23 on the surface and two are sandwiched between the solar cell panel 21 and the back panel 23, and the adhesive layer 24 between the solar cell panel 21 and the cover panel 22, respectively. The solar cell panel 21 includes a photoelectric conversion layer (not shown), and a conductive circuit layer (not shown) formed on the photoelectric conversion layer. The photoelectric conversion layer may include single crystal, polycrystalline, non-crystalline Silicon or other silicon crystal materials, or other materials that can be used for photoelectric conversion, the conductive circuit layer can be metal, conductive metal oxide and other conductive materials with good conductivity; the material of the glue layer 24 is a solar cell Commonly used glue materials, such as polyethylene vinyl acetate (Ethylene-vinyl acetate, EVA), polyvinyl butyral (Polyvinyl butyral, PVB), or polyolefin elastomer (Polyolefin elastomer, POE).

The cover plate 22 is selected from materials that can transmit light and is not easily affected by light, such as glass; the back plate 23 can be made of polymer materials, such as polyester (PET), polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), polyolefin (POE), or glass. In this embodiment, the cover plate 22 of the solar module 2 is glass, and the back plate 23 is a polyvinyl fluoride (PVDF) polymer material For example.

Specifically, a first embodiment of the solar cell module recycling method includes a first disassembly step 31 and a second disassembly step 32.

The first disassembly step 31 is to provide the aforementioned solar module 2 and place the solar module 2 in a non-polar solvent under a pressure between 1 and 5 kg/cm ² to make the solar cell The plate 21 is separated from the back plate 23 to obtain a first dismantling object 300 including at least the solar cell panel 21 and at least one glue layer 24.

In detail, in the first disassembling step 31, the solar module 2 is placed in a closed tank containing a non-polar solvent, and heated to a temperature greater than the boiling point of the non-polar solvent by an oil bath or electric heating, etc. The non-polar solvent is evaporated to form steam and maintained at a predetermined vapor pressure (1~5Kg/cm ² ) for about 2~3 hours.

The non-polar solvent may be selected from alkanes or alkenes having a boiling point of not more than 150°C, wherein the alkanes may be selected from but not limited to pentane, octane, hexane, and the alkenes may be selected from but not limited to cyclohexene , Octene, nonene. The non-polar vapor molecules penetrate into the glue layers 24 by high pressure to break the bond between the glue layer 24 and the polymer material, so that the adhesion between the glue layer 24 and the back plate 23 is reduced, so the solar module The back plate 23 in group 2 will first be separated from the adjacent glue layer 24.

Preferably, the non-polar solvent is selected from alkane or alkene with a boiling point between 30°C and 120°C, and the pressure is between 1 and 4 kg/cm ² .

In the first embodiment, the non-polar solvent is hexane as an example, which is heated to about 70-80°C by an oil bath heating method, the vapor pressure is about 2~4kg/cm ² and the temperature is maintained for 2.5 hours to obtain Including the back sheet 23, and the adhesive layer 24 adhered to the two opposite surfaces of the solar cell panel 21 and the cover plate 22 adhered to one of the adhesive layers 24 (cover plate 22/adhesive layer 24/solar panel 21/adhesive layer 24) Combination of the first dismantling object 300.

The second disassembly step 32 is to place the combination of the cover plate 22/glue layer 24/solar panel 21/glue layer 24 of the first demolition object 300 in a water vapor environment or a non-polar solvent with a temperature not less than 100°C In at least one of them, the cover plate 22 is separated from the solar cell panel 21.

Specifically, the second disassembly step 32 includes two sub-steps. The first step is to detach the cover plate 22 using high-pressure steam, and the second step is to perform the process with microwave in a non-polar solvent The separation of the solar panel 21 and the glue layer 24.

Specifically, the first step is to place the cover plate 22/glue layer 24/solar panel 21/glue layer 24 combination at 120 to 190° C. and a vapor pressure between 1 and 10 kg/cm ² of water In a steam environment for about 1 to 12 hours, the bonding between the adhesive layer 24 and the glass is broken by high-pressure water vapor to reduce the adhesion between the adhesive layer 24 and the cover plate 22, and the cover plate 22 and the phase The adjacent adhesive layer 24 is separated to obtain the detached cover plate 22 and the adhesive layer 24 (adhesive layer 24/solar panel 21/adhesive layer 24) bonded to the two opposite surfaces of the solar panel 21 )'S combined second dismantling object 301.

Next, a second step is performed, and the combination of the adhesive layer 24/solar panel 21/adhesive layer 24 of the second dismantling object 301 is placed in a non-polar solvent with a boiling temperature greater than 150°C and heated by microwave To make the temperature of the conductive circuit layer of the solar panel 21 not less than the cracking temperature of the glue layer 24 (about 450~500°C), and continue microwave heating for about 1~5 minutes, so that the glue layer 24 and the The bonding interface of the conductive circuit layer loses its viscosity due to high temperature cracking, so that the solar cell panel 21 is separated from the adhesive layers 24, and the adhesive layers 24 can be recovered. The microwave can be used to quickly separate the glue layers 24 from the solar cell panel 21, so the disassembly time of the solar module 2 can be shortened, and the overall recycling process can be made more efficient.

It should be noted that the first step and the second step mentioned above are only different steps, and there is no order separation. In actual implementation, the second step may be performed first, and then the composition containing the cover plate 22 and the adhesive layer 24 may be disassembled using the first step.

The microwave will not heat the non-polar solvent, but when the conductive circuit layer of the solar cell panel 21 is exposed to microwaves, it will generate high temperature due to the arc. Therefore, the present invention uses microwaves to act on the conductive circuit layer to make the conductive circuit The temperature of the layer can reach the cracking temperature of the glue layer 24 (approximately 450-500°C), so that the interface between the glue layer 24 and the conductive circuit layer loses its viscosity due to high-temperature cracking, so that the solar panel 21 Separated from the glue layers 24, and at the same time using the non-polar solvent as a heat dissipation medium, the high temperature of the conductive circuit layer can be dissipated by the non-polar solvent to avoid the problem of excessive temperature caused by continuous microwaves.

Preferably, the non-polar solvent may be selected from alkanes or alkenes having a boiling point greater than 150°C. The alkanes may be selected from but not limited to octane, nonane, decane, and the alkenes may be selected from but not limited to octene , Nonene, octadecene and other non-polar solvents.

In this embodiment, the non-polar solvent in the second step is octadecene (Octadecene, ODE, boiling point 314°C) as an example, and the combination of the adhesive layer 24/solar panel 21/adhesive layer 24 is set. In the octadecene solution, the microwave power is set to 200W for about 2 minutes for disassembly, and the solar panel 21 can be separated from the adhesive layers 24.

This embodiment of the recycling method of the solar cell module of the present invention utilizes the characteristics of the non-polar solvent vapor to penetrate the glue layer 24 with good permeability and low solubility, and is supplemented by pressure to allow the non-polar solvent molecules to penetrate into the glue layer 24 and Between the back plates 23, the bonding between the adhesive layer 24 and the polymer back plate 23 is broken to reduce the viscosity and the back plate 23 can be detached; then, water vapor is used to make polar water molecules penetrate into the adhesive layers 24 and The bonding interface of the polar materials (cover plate 22, solar cell panel 21) destroys the affinity between the adhesive layer 24 and the polar material to reduce the viscosity and separate the cover plate 22 from the solar cell panel 21, using microwave and non- The combination of polar solvents allows the microwave to directly act on the conductive circuit layer of the solar cell panel 21 to generate a high temperature of the cleavable adhesive layer 24, which separates the adhesive layer 24 from the solar cell panel 21, therefore, the overall disassembly separation process will not After dissolving the adhesive layers 24, the solar modules 2 can be disassembled to obtain more complete adhesive layers 24, which is beneficial for subsequent recycling. In addition, since the glue layers 24 will not dissolve in the non-polar solvent or water vapor, the used solvent does not need to undergo additional procedures to remove the dissolved glue material, which can reduce the recycling process of the solar module and can To achieve the effect of environmental protection.

It should be further explained that each embodiment of the solar cell module recycling method of the present invention may further include at least one of a back sheet recycling step, a glass sheet recycling step, and a battery recycling step to further The detached back plate 23, cover plate 22, and solar cell panel 21 are recovered.

The back sheet recycling step is to disassemble the back sheet 23 obtained by disassembling the solar module 2 by using an organic alkali solvent to decompose and recover. The organic alkali solvent may be selected from, but not limited to, octylamine (Octylamine) or Oleylamine.

In the glass plate recovery step, the cover plate 22 obtained by disassembling the solar module 2 is used to remove residual adhesive on the surface by liquid olefins, and washed with water to recover the glass plate 22. Wherein, the liquid olefin can be selected from but not limited to octene, nonene and octadecene.

In the battery recovery step, the solar cell panel 21 obtained by disassembling the solar module 2 is immersed in an acid solution by removing residual surface glue using liquid olefins, so that the conductive circuit in the solar cell panel 21 The layer is dissolved in the acid solution, and the silicon crystal layer is separated from the conductive circuit layer for the subsequent silicon crystal layer recovery process, wherein the acid solution may be selected from but not limited to sulfuric acid or nitric acid.

It should be noted that the above-mentioned glass recycling step, the back plate recycling step, and the battery recycling step recycling procedure and related drugs are known to those skilled in the art, so they will not be repeated here.

In summary, the recycling method of the solar cell module of the present invention utilizes pressure supplemented by non-polar steam and water vapor, so that non-polar molecules and water vapor molecules can penetrate into the back plate 23 and the cover plate 22 and the glue layer 24 The interface between the adhesive layer 24 and the polymer back plate 23 and the adhesive layer 24 and the glass cover plate 22, which can separate the back plate 23 and the cover plate 22 from the solar cell panel 21, in addition, The microwave is used in conjunction with the non-polar solvent, and the high temperature generated by the microwave acting on the conductive circuit layer causes the interface between the glue layer 24 and the conductive circuit layer to lose its viscosity due to high temperature cracking, and further the solar cell panel 21 and These separate the glued layers 24. Since the glue layer 24 will not be dissolved during the disassembly process, the more complete glue layer 24 can be obtained after the solar module 2 is disassembled, which is beneficial for subsequent recycling. In addition, since the glue layers 24 will not dissolve in the non-polar solvent or water vapor, the used solvent does not need to undergo additional procedures to remove the dissolved glue material, which can reduce the recycling process of the solar module and can To achieve the effect of environmental protection, and to facilitate the recycling of the glue layer 24, so it can indeed achieve the purpose of cost invention.

However, the above are only examples of the present invention, and should not be used to limit the scope of the present invention. Any simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the content of the patent specification are still classified as This invention covers the patent.

31‧‧‧The first disassembly step

23‧‧‧Backboard

32‧‧‧Second dismantling step

24‧‧‧Glue layer

2‧‧‧Solar Module

300‧‧‧The first dismantling object

21‧‧‧Solar Panel

301‧‧‧Second dismantling object

22‧‧‧Cover

Other features and functions of the present invention will be clearly presented in the embodiment with reference to the drawings, in which: FIG. 1 is a text flow diagram illustrating the method of recycling the solar cell module of the present invention; an embodiment; and FIG. 2 It is a schematic diagram of the flow, which assists in explaining FIG. 1.

31‧‧‧The first disassembly step

32‧‧‧Second dismantling step

Claims (8)

A method for recycling a solar cell module, including: a first disassembly step to provide a solar module including a solar cell panel and a light-transmittable cover provided on one surface of the solar cell Plate, a back plate provided on the other surface of the solar cell opposite to the cover plate, and two respectively sandwiched between the solar cell plate and the cover plate, and the adhesive layer between the solar cell plate and the back plate , Where the solar cell panel includes a silicon crystal layer and a metal circuit layer formed on the silicon crystal layer, and the backplane is made of a polymer material, the solar module is placed in a non-polar solvent, and in Under the condition of pressure between 1~5Kg/cm ² , the solar panel is separated from the back sheet to obtain a first dismantling object; a second disassembling step, the first dismantling object is placed at a temperature not less than In at least one of a water vapor environment of 100°C or a non-polar solvent, the cover plate is separated from the solar cell panel; and a step of recovering the battery will utilize the liquid olefins for the solar cell panel after removing the glue layers After removing the residual glue on the surface, it is immersed in an acid solution to dissolve the conductive circuit layer in the acid solution, and the silicon crystal layer is separated from the conductive circuit layer and recovered separately. The method for recovering a solar cell module according to claim 1, wherein the first disassembling step is to heat the solar module in a closed tank containing a non-polar solvent with a boiling point of not more than 150°C, and The pressure is between 1 and 4 Kg/cm ² , and the back sheet is separated from the solar panel. The method for recycling a solar cell module according to claim 2, wherein the non- The polar solvent is selected from alkanes or alkenes with boiling points between 30 and 120°C. The method for recycling a solar cell module according to claim 1, wherein the solar cell panel includes a silicon crystal layer and a conductive circuit layer formed on the silicon crystal layer, the second disassembly step is to replace the first The dismantled product is placed in a non-polar solvent with a boiling temperature greater than 120°C, and the microwave heating method is used to make the temperature of the conductive circuit layer not less than the cracking temperature of the glue layer, so that the solar panel and the adjacent The glue layer is separated, and the cover plate is separated from the solar panel. The method for recovering a solar cell module according to claim 4, wherein the non-polar solvent is selected from alkanes or alkenes having a boiling point greater than 150°C. The method for recovering a solar cell module according to claim 1, wherein the second disassembling step is to place the first dismantling object in a closed container containing high-temperature water vapor, and the water vapor temperature is between 120 and 190 ℃, and the vapor pressure is between 1~10Kg/cm ² , so that the cover plate is separated from the solar panel. The method for recovering a solar cell module according to claim 1, further comprising a step of recovering the back sheet, and the separated back sheet is decomposed and recovered by organic alkalis. The method for recovering a solar cell module according to claim 1, further comprising a step of recovering a glass plate, and using the liquid olefins to remove the residual adhesive on the separated glass plate and washing with water to recover.

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