Solar panel recycling system and method

Abstract

The recycling of solar panels has been solved by the structural arrangement of the units of the solar panel recycling system, which is characterized in that it comprises a unit for storing solar panels, a preliminary disassembly unit, a unit for storing the aluminum frame, a unit for storing the j unction box, a washing and drying unit, a secondary disassembly unit, a disc mill, a separator, a unit for storing the fine fraction, a unit for storing the coarse fraction, a pyrolysis reactor vessel, a primary technological pipeline outlet, a secondary technological pipeline outlet, a primary technological pipeline, a secondary technological pipeline, a thermal treatment zone, a reactor vessel cooling zone, a primary dust separating cyclone, a primary condenser, a primary technological liquid pipeline, a primary liquid storage tank, a primary gas storage tank, a secondary dust separating cyclone, a dehalogenator, a secondary condenser, a secondary technological liquid pipeline, a secondary liquid storage tank, a gas separator unit, a secondary gas storage tank, a secondary technological gas pipeline, a count er- cur rent plate dust separating unit, a wet chemical processing unit, a collection vessel, a gas mixing unit, an ex-situ catalyst bed, and an electric power generating unit. The present invention further relates to the process for recycling solar panels.

Description

[0001] Solar panel recycling system and method

[0002] Field of the Invention

[0003] The present patent relates to a system for recycling solar panels, which is specifically suitable for processing different types of intact, defective, or damaged photovoltaic solar panels, for the separation and recycling of their subunits. The invention further relates to a procedure comprising the preparation of the solar panels, their grinding, their primary mechanical separation, their thermolysis, the proper purification of the gas product formed, and the wet-chemical processing of the solid waste generated.

[0004] Background of the Invention

[0005] By the end of 2021, the annual global electricity generation of silicon-based photovoltaic systems exceeded 1,000 TWh. This was in line with the guidelines set in the 2015 Paris Agreement on climate change. However, the large-scale deployment of silicon- based photovoltaic (PV) panels poses a societal and environmental threat to the biosphere, as the amount of electronic waste (e-waste) originating from such panels is expected to reach approximately 78 million tons by 2050 [Kant, N., Singh, P., 2022. Review of next generation photovoltaic solar cell technology and comparative materialistic development. Materials Today: Proceedings 56, 3460-3470] .

[0006] The processing of end-of-life PV panels is of high priority, as the most common current treatment method is disposal in landfills, due to the absence of an optimal solution for large- scale industrial processing. Improper handling presents numerous environmental and health risks; therefore, adequate management of this issue is essential.

[0007] The primary source of the various risks lies in the presence of hazardous substances within the panel materials and their potential release into the biosphere. Among the different types of solar panels, those containing polycrystalline silicon cells represent the most widespread category among panels requiring processing. A typical panel of this kind has a mass of approximately 20.0 kg, which, referenced to 1,000.0 kg of product, consists of the following components: junction box: 20.0 kg; tempered glass: 680.0 kg; aluminum frame: 180.9 kg; cell backsheet: 5.0 kg; copper cable: 3.3 kg; copper cable covering: 6.6 kg; conductor ribbon: 1.1 kg; polymer (e.g. EVA) : 51.0 kg; backsheet (e.g. Tedlar, Kynar) : 15.0 kg; silicon: 36.5 kg; silver: 0.3 kg; other metals (e.g. Sn, Pb) : 0.29 kg. [Rong D., Nathan L., Chang Z. Q. , Chee M. C . , A techno-economic review of silicon photovoltaic module recycling, Renewable and Sustainable Energy Reviews, 2019, 109, 532-550] . The listed proportions represent a typical composition of a photovoltaic panel. From the perspective of processing and recycling, the most critical and environmentally harmful constituents are the halogen-containing polymers (PVF - polyvinyl fluoride; PVDF - polyvinylidene fluoride) forming the panel backsheet, as well as the tin and lead present as coatings on the conductive copper ribbons. During processing, the proper handling of these components and the neutralization of harmful substances are therefore of particular importance.

[0008] In view of the value of the raw materials constituting photovoltaic panels, it is of particular importance that, in addition to the safe disposal and processing of the resulting waste, the highest possible proportion of these raw materials be recovered. At the current rate of waste generation, the disposal of solar panels will pose a significant environmental problem over the next two decades [M. Marwede, W. Berger, M. Schlummer, A. Maurer, A. Reller, Recycling paths for thin- film chalcogenide photovoltaic waste - Current feasible processes, Renewable Energy 55 (2013) 220.] . According to the state of the art, several photovoltaic panel recycling devices , as well as various physical , thermal and / or wet-chemical processes , are known .

[0009] Physical methods include the mechanical treatment of PV panels , such as cutting, shredding, and grinding . The process disclosed in patent application US20240304745A1 employs control and measurement techniques by which the separation of the materials constituting the panels is optimi zed, thereby improving recycling ef ficiency and reducing the amount of waste requiring disposal . According to the procedure recorded in the patent , the glass and the backsheet are removed from the front and rear sides of the panels by cutting / milling .

[0010] According to patent application US20240293952A1 , layers are removed from the rear surface of the solar panel using high- pressure water without damaging the cover glass situated beneath . The process , however, generates a signi ficant amount of wastewater .

[0011] In the thermal method for recycling solar panels , high temperature is applied for the removal of the adhesive material and the backsheet in order that the valuable raw materials can be recovered . The patent filed by J . Weinfurtner in 1996 under registration number DE4418573C1 concerns the recycling of laminated solar panels , in which the laminated solar panels are first heat-treated at a temperature of 500 ° C for 1 hour in an oxygen atmosphere . After the departure of the organic material , the panels are cooled with the help of water spraying . Following the cooling, the glass forming the panel and other metals are separately separated .

[0012] Bohland and Anisimov patented a silicon solar cell recycling process for First Solar Company (US6063995A) . In this process , the photovoltaic panels are heated to 500 ° C, after which the intact silicon cells are recovered . According to the disclosure , the recycled cells exhibited 80% of the electrical ef ficiency of non-recycled cells . The process is suitable for treating panels having a speci fic structural configuration .

[0013] The delamination of the EVA layer by wet-chemical methods involves the partial or complete dissolution of the adhesive material . During the procedure, the adhesion between the glass and the adhesive material decreases , which makes possible the separation of the components forming the solar panel . Patent application No . WO2022123444A1 applies a two-step grinding process , during which the units forming the solar panel are fractionated according to si ze, and then the individual parts are treated with di f ferent wet-chemical procedures in order to recover the valuable raw materials .

[0014] Patent application WO2024216338 proposes the use of an ionic liquid and an organic solvent for the appropriate treatment of the halogens present in the backsheet of photovoltaic panels .

[0015] Further solutions that combine various processing methods (physical , thermal , and wet-chemical ) also form part of the relevant state of the art for the purposes of the present invention .

[0016] In patent application WO2023239296A1 , the backsheet of the photovoltaic panel and the EVA layer are removed by heating in an oxygen atmosphere in such a manner that the glass portion remains intact . The process also includes selective and rapid silver extraction; however, the nitric acid employed likewise dissolves the conductive ribbons . At the end of the process , the recovered tempered glass is ground to a particle si ze suitable for various applications .

[0017] According to the procedure disclosed in US11712682B2 , a method is proposed for performing pyrolysis in the presence of a catalyst . The application of a mica-based catalyst is demonstrated in two distinct processes . In one embodiment , the thermolysis of polymer-based waste is conducted in a continuous reactor, whereas the other method describes the pyrolysis of photovoltaic modules . The thermal decomposition of the photovoltaic panels is carried out in a batch operation, wherein the solar panels and the catalyst are placed, without prior preparation, onto a tray-type loading unit .

[0018] In the state of the art , the sub-units of solar panel recycling apparatuses are intended to carry out individual steps of recycling and / or processing . Thus , for the implementation of complete recycling and / or process ing, several apparatuses are required, which must follow one another in the appropriate sequence . Since complete recycling and / or processing is not achieved in the solutions according to the current state of the art , it may occur that the panels are not properly prepared, valuable raw materials end up as waste, and furthermore the environmentally harmful compounds generated are not neutrali zed . Partial processing and / or recycling of a solar panel currently results in a greater environmental burden than expected .

[0019] It has further been recogni zed that the compounds generated during the processing and / or recycling of solar panels have high price and energy value , and by re-using them the energy demand of the apparatus can be reduced . In the system according to the present invention, organic and inorganic solvents are applied exclusively in the final step of processing and / or recycling, thereby reducing the environmental damage caused by solvents , lowering the safety risks arising during the process , and furthermore requiring the storage and regeneration of a smaller quantity of solvents .

[0020] It has also been recognized that the disadvantages of the solutions belonging to the state o f the art , as mentioned in the introduction, can be eliminated by creating a system and process suitable for the complete recycling and / or processing of solar panels , which includes a unit for optimal crushing of solar panels, a unit for separating the granulate, and proper handling of the high-value and high-energy products generated during processing .

[0021] Brief description of the drawings

[0022] Figure 1: shows a block diagram of the photovoltaic panel recycling system according to the present patent.

[0023] Brief summary of the invention

[0024] On the basis of the above recognitions, the set task has been solved by the structural arrangement of the units of a solar panel recycling system, which is characterised by comprising a unit for storing solar panels, a preliminary disassembly unit, a unit for storing aluminum frame, a unit for storing junction box, a washing and drying unit, a secondary disassembly unit, a disc mill, a separator, a unit for storing fine fraction, a unit for storing coarse fraction, a pyrolysis reactor vessel, a primary technological pipeline outlet, a secondary technological pipeline outlet, a primary technological pipeline, a secondary technological pipeline, a thermal treatment zone, a reactor vessel cooling zone, a primary dust-separating cyclone, a primary condenser, a primary technological liquid pipeline, a primary liquid tank, a primary gas tank, a secondary dust-separating cyclone, a halogen remover, a secondary condenser, a secondary technological liquid pipeline, a secondary liquid tank, a gas separator unit, a secondary gas tank, a secondary technological gas pipeline, a counter-current plate dust-separating unit, a wet-chemical processing unit, a collecting vessel, a gas mixing unit, an ex-situ catalyst charge, and an electric power generating unit.

[0025] The invention preferably relates to a system for recycling solar panels, wherein in the disc mill the distance between the cutting edges is in the range of 2.0 - 0.5 mm, and most preferably between 1.0 - 0.5 mm. The invention further relates to a solar panel recycling system, in which the rotational speed of the grinding elements in the disc mill is 200- 600 rpm, more preferably between 300-500 rpm, and most preferably 400 rpm .

[0026] According to another advantageous embodiment of the solar panel recycling system, the material of the grinding elements in the disc mill is selected from the following list : aluminum oxide , tungsten carbide / cobalt cermet , most preferably the material of the grinding elements is tungsten carbide / cobalt cermet .

[0027] According to a further advantageous embodiment of the solar panel recycling system, the metal mesh of the separator is made of wear-resistant metal and has a lattice constant between 2- 6 mm, more preferably between 2-3 mm, and most preferably 2 mm . According to another advantageous embodiment of the solar panel recycling system, the metal mesh of the counter-current plate dust-separating unit is wear-res istant metal , with a lattice constant between 20-1 mm, more preferably between 10-1 mm, and most preferably 5 mm .

[0028] The present invention further relates to a process for recycling solar panels .

[0029] In the course of recycling solar panels , we proceed in such a way that , as a first step, the solar panels to be recycled are placed into a unit for storing solar panels ; from which, in a preliminary disassembly unit , the aluminum frames and j unction boxes of the panels are removed; thereafter, the panels obtained without frames and j unction boxes are placed into a washing and drying unit ; from which the washed and dried panels are trans ferred into a secondary disassembly unit and cut to a predetermined width; subsequently, the panels are crushed in a disc mill ; the crushed material is conveyed to a separator, where coarse and fine fractions are separated from one another and these fractions are stored in dedicated storage units ; then, the coarse fraction, together with the unit for storing coarse fraction, is placed into a pyrolysis reactor vessel with the help of a apparatus moving unit ; then the pyrolysis reactor vessel is placed into a thermal treatment zone , where the coarse fraction undergoes thermal treatment in one or two steps under given heat-treatment parameters ; then, the vaporous product formed in the first stage of thermal treatment is conducted through the primary technological pipeline to a primary dust-separating cyclone ; from there the gas formed in the previous step is directed to a primary condenser, where it is separated into liquid and gaseous substances ; then the liquid obtained is stored in the respective liquid tank, while the gas is conducted through a pipeline into the primary gas tank; in the case when the thermolysis temperature exceeds 450 ° C, the vaporous product formed is conducted through a secondary technological pipeline to a secondary dust-separating cyclone ; from there , the gas is conducted into the gas mixing unit , into which the gas stored in the primary gas tank is also introduced, in the case when it is necessary to carry out the first step as well ; then, in the next step, the particles and halogen- free vapor are conducted to the secondary condenser, where the liquid and gaseous components present in the vaporous product are separated; then the liquid product formed in the previous step is conducted into and stored in the secondary liquid storage unit , and the gaseous product is conducted through the gas separator unit into and stored in the secondary gas tank; then the liquid and gas formed during the secondary condensation process are conducted into the electric power generating unit ; furthermore , at the end of the thermal treatment process , the pyrolysis reactor vessel is placed into the cooling zone , then the unit for storing the coarse fraction is removed, which contains the solid fraction remaining during the thermolysis , which is placed into the counter-current plate dust-separating unit ; from there , the dust- free solid fraction is conducted into the wet-chemical processing unit , where the final recovery of the elements forming the solar panels takes place .

[0030] Detailed description of the invention

[0031] In the description of the present patent , the recycling of solar panels is defined as processing solar panels (whether aged, defective , or damaged panels ) in such a way that the products and by-products obtained are marketable , i . e . , reusable , losses minimi zed, and any harmful substances that may be generated, i f they have high energy content , are recycled, otherwise they are disposed of f . Furthermore , the term recycling equally encompasses mechanical , thermal , and chemical processing methods , as well as combinations thereof . In the present patent speci fication, the term processing is understood to mean a procedure involving one or more operational steps , the totality of which constitutes recycling in the case where the recovered products and by-products are reused and / or marketed . The system in which the recycling of solar panels takes place is hereinafter referred to as 100 solar panel recycling system .

[0032] It is noted that within the scope of the present description, whenever a range is defined, the speci fic numerical values indicated as the boundary values of the range are to be considered as forming part of the range .

[0033] The first element of the solar panel recycling system is the 1 unit for storing solar panels . In placing the panels to be processed, it is important to maintain constant temperature and humidity, and furthermore that the storage takes place in an enclosed space in order to prevent possible delamination, degradation, and the release of hazardous substances into the environment . Protection from sunl ight and other high-intensity arti ficial light sources is likewise an essential feature of the 1 unit for storing solar panels , since waste solar panels may still retain functionality and are capable of generating electric current in the presence of light , which poses a risk of inflammation .

[0034] From the 1 unit for storing solar panels , the photovoltaic panels are trans ferred into the 2 preliminary disassembly unit with the help of a apparatus moving unit . A conveyor-type material-trans fer unit of similar construction is employed between several processing devices during the recycling process , although it is not indicated in Figure 1 . In the 2 preliminary disassembly unit , the aluminum frame and the j unction box are mechanically removed . These sub-units , following disassembly, are placed into the 3 aluminum frame storage unit and the 4 j unction box storage unit , respectively, until further processing or sale .

[0035] The solar panels without frames and j unction boxes are preferably cleaned after disassembly, since during thermolysis undesired substances may enter the reaction chamber, which at high temperature may lead to the formation of unexpected by-products . Cleaning is advantageously carried out by repeated washing with distilled / contaminant- f ree water in the 5 washing and drying unit . During drying, the solar panels are dried to constant mass by heat removal from the cooling zone of reactor vessel 13 . By this method, even in the case of delaminated or heavily contaminated panels , the introduction of contaminants into the reaction chamber and the contamination of the products recovered during recycling can be minimi zed .

[0036] The cleaned solar panels must be cut to appropriate si ze depending on the configuration of the 7 disc mill . The cutting is carried out by a blade-cutting method in the 6 secondary disassembly unit , where the solar panels are placed on a conveyor belt such that the front surface on the tempered glass side is in contact with the conveyor belt . Following positioning, blades made of wear-resistant steel or other hard metal are applied to the backsheet of the solar panels , where , under the force generated by the movement of the conveyor belt , the blades cut through those layers of the solar panel which are located above the glass side . The maximum spacing of the blades is preferably equal to the minimum diameter of the feed opening of the 7 disc mill . During the process , and as a final step, the glass sheet preferably breaks , thereby enabling separation of the cut pieces produced during the process . By means of this step, the 100 solar panel recycling system is adaptable to the processing of di f ferent panel constructions . Due to the material properties of the typically thermally tempered glass sheet , it fractures into splinters , and owing to the adhesion between the adhesive material and the glass , it does not separate from the polymer layers .

[0037] The product generated in the 6 secondary disassembly unit is stored in a specially designed 26 collection vessel , and subsequently fed through the inlet opening of the 7 disc mill . During feeding, the material to be ground enters between the discs arranged vertically relative to each other, where one disc is in a fixed position, and relative to this , the counter-disc attached to the motor rotates . Following feeding, under the centri fugal force developed in the 7 disc mill , the solar panel fragments are directed between the shredding lamellae , where , under the action of shear force , the tempered glass is separated from the adhesive containing the silicon wafer, conductor ribbon, and backsheet . In order to reduce the energy demand of the grinding process , it is advantageous to pre-cut the solar panels , since thereby less energy is required to introduce the fragments between the cutting and separating edges .

[0038] Tokoro et al . [ C . Tokoro , M . Ni shi , Y . Tsunazawa, Selective grinding of glass to remove resin for silicon-based photovoltaic panel recycling, Adv . Powder Technol . 32 ( 2021 ) 841 - 849 ] demonstrated that the constituent elements of solar panels can also be separated by means of a batch-operated eccentric mixing mill. Particle-size analysis revealed that the fraction smaller than 2 mm contained exclusively glass. Granata et al. [G. Granata, F. Pagnanelli, E. Moscardini, T. Havlik, L. Toro, Recycling of photovoltaic panels by physical operations, Sol. Energy Mater. Sol. 123 (2014) 239-248] employed a twin-blade shredder and a jaw crusher in combination for the mechanical processing of photovoltaic panels. They showed that each fraction of different size ranges contained glass. The highest glass content (85 wt%) was in the fraction between 1-8 mm. It has thus been demonstrated by the aforementioned researchers that, by means of grinding techniques, the sub-units constituting the solar panels can be separated from one another. In the case of an eccentric mill, cutting is primarily the separating mechanism, whereas in the twin-blade rotor shredder and aw crusher, shear and impact forces dominate. The advantage of the 7 disc mill compared to these is that it is capable of selectively separating the individual components of photovoltaic panels in continuous operation, in a single step, wherein under the shear force arising between the discs, the glass particles detach from the surface of the adhesive.

[0039] Our experiments with the 7 disc mill demonstrated that within a maximum of 4 minutes a significant portion of the glass can be removed, and the fine fraction thus obtained contains less than 3 wt% polymer. The glass granulate obtained during the grinding process can advantageously be separated into two fractions. In one case, the particle size is smaller than 2 mm and consists predominantly of glass (greater than 97 wt%) . In the other case, the fraction contains particles larger than 2 mm, where our measurements confirmed that this phase contains more than 70 wt% polymer. Further investigations of grinding processes carried out with the 7 disc mill revealed that the relative spacing of the discs can advantageously be used to vary the efficiency of the 7 disc mill process. When the distance between the discs is greater than 3 mm, more than 90 wt% of the mass of the solar panels subj ected to cutting falls into the fraction larger than 2 mm, meaning that the material to be processed passes between the discs without interaction . However, when the distance between the discs is at most 2 mm, then depending on the type of solar panel , the fraction smaller than 2 mm is expected to contain less than 2 wt% polymer . In order to carry out selective mechanical separation with the aid of the disc mill , the rotational speed of the moving disc must be at most 600 revolutions per minute , at least 300 revolutions per minute , and most preferably 400 revolutions per minute .

[0040] Since the hardness of the components forming the photovoltaic solar panels is high and signi ficant shear forces prevail in the space between the discs , a material with such properties is required for the construction of the 7 disc mill whose mechanical resistance is outstanding against the abrasive and shear stresses arising on the surfaces of the discs . Therefore , the discs forming the 7 disc mill , which are the grinding elements resistant to mechanical stresses , are preferably made of tungsten carbide-cobalt / cobalt composite , aluminum oxide , or zirconium oxide .

[0041] The grinding mechanisms in the 7 disc mill are suitable for separating the heterogeneous fraction leaving the 7 disc mill according to particle si ze . When the glass is separated from the high-polymer-content fraction, the ef ficiency of thermolysis can be increased . In the industry, it sometimes occurs that solar panels are heated together with the glass ; however, under high temperature the glass may soften and / or fracture , which complicates the further treatment of the solid phase remaining after the reaction . This problem can be addressed by placing an 8 separator beneath the outlet opening of the disc mill , the metallic mesh of which is preferably made of wear-resistant steel . The lattice constant of the metallic mesh is at most 4 mm, preferably 2 mm . In the latter case , from the homogeneous granulate deposited on one side of the mesh, the glass waste smaller than 2 mm falls by gravitational force into the 9 unit for storing fine fraction. The fraction larger than 2 mm, having high polymer content, remains on the mesh and continues onward, falling into a specially designed 10 unit for storing coarse fraction at the opposite end of the mesh. During the process, the continuous metallic mesh rotates in the clockwise direction and vibrates with appropriate amplitude, thereby enhancing the efficiency of size-based separation. The fine fraction smaller than 2 mm generated during the grinding process is by itself suitable for use in the construction industry as an additive, since it does not contain significant contamination. In cases of necessity, it occurs in the industry that possible contamination adhered to the surface of the glass particles is removed with organic solvents or mixtures thereof. In this dissolution procedure requires a significant amount of organic solvent, which typically dissolves unreacted monomers and thereby only reduces adhesion between the glass surface and the adhesive material. Thus, the result of the dissolution process is contaminated organic solvent and plastic waste. However, the contaminant polymer layer on the surface of the fine fraction can also be removed thermally, thereby producing high-purity glass, which can be further utilized in numerous industries.

[0042] The 10 unit for storing coarse fraction / containing the coarse fraction, is in itself suitable to be placed into the 11 pyrolysis reactor vessel specifically designed for this purpose. In the case of processing polycrystalline solar panels, 1000 kg of coarse fraction contains the following components (the quantities given herein are merely illustrative) : 10 kg copper conductor ribbon; 466 kg adhesive material (e.g., EVA) ; 138 kg backsheet (e.g., PVF) ; 333 kg silicon cells; 27 kg silver; 26 kg other metals (e.g., Sn, Pb) . One of the central elements of the 100 solar panel recycling system is the 11 pyrolysis reactor vessel , where the thermolysis of the coarse fraction takes place . Among these raw materials , the adhesive material is present in the largest amount , and its thermal decomposition produces energy-rich products in the form of oil and gas . The most commonly used adhesive is the ethylene-vinyl acetate (EVA) copolymer, the thermal decomposition of which occurs in two stages . The mechanism of the first decomposition stage can be approximated by a three-dimensional di f fusion reaction based on the Anti-Jander equation, with a temperature range of 280-380 ° C in the case of EVA. In this phase , the main reaction product is acetic acid, alongside which, depending on the heating rate , varying amounts of carbon monoxide , carbon dioxide, and methane are formed . When the heating rate is 25 ° C / min, the maximum formation of acetic acid falls within the temperature range of 310-330 ° C, and the amount of acetic acid produced exceeds that of the carbon dioxide formed . At this treatment peak temperature , the mass of the EVA adhesive typically decreases by 19-22 % by weight . In addition to the decomposition of the adhes ive , the thermal degradation of the backsheet also begins in the temperature range of 280- 380 ° C .

[0043] Among the types of backsheets , two principal characteristic types are distinguished . One such material is the Tedlar ( TPT ) type composite , which contains a 260-270 micrometer polyethylene terephthalate ( PET ) layer sandwiched between two 30-40 micrometer polyvinyl fluoride ( PVF) layers . The other is the Kynar (KPK) type film, in which a 260-270 micrometer PET film has on each side a 30-40 micrometer polyvinylidene fluoride ( PVDF) film . The white color of these backsheets is imparted by titanium dioxide present in the f ilm material , typically in an amount of 16-20 wt% . In the first stage of the decomposition process , the backsheets exhibit a mass loss of 1-3 wt% , resulting from the thermal degradation of PVF and PVDF; thus, halogen formation must be considered even in the initial stage of the reaction. During thermolysis of 1000 kg of PVF / PVDF-based backsheet, 100-200 grams of elemental fluorine may be generated. The decomposition of PET film at a heating rate of 25 °C / min occurs in the temperature range of 390-530 °C, meaning that the principal components of the gaseous products formed in the first stage of decomposition are acetic acid and carbon dioxide, with minor amounts of carbon monoxide, methane, nitrogen, and traces of fluorocarbons. Other components of the coarse fraction obtained by grinding (copper conductor ribbon, silicon, silver, and other metals) do not exhibit significant physico-chemical changes at this temperature.

[0044] The second stage of EVA decomposition can be described according to the Valensi model, typically occurring in the temperature range of 450-650 °C. In this range, complete thermal decomposition of the adhesive material present in the coarse fraction takes place, with the main reaction products being hydrogen, carbon monoxide, carbon dioxide, methane, and short- and long-chain hydrocarbons (e.g., alkenes, olefins, and aromatic compounds) . For EVA, at a heating rate of 25 °C / min, the mass loss is an additional 78-81 wt%.

[0045] At a temperature of 540-560 °C, the complete thermal decomposition of PVF / PVDF-type backsheets and PET film also occurs, where the amount of halogen formation, calculated for 1000 kg of backsheet, is 0.9-1.0 kg. During thermal degradation of the backsheet, the principal products are carbon dioxide, hydrogen, methane, and short- and long-chain compounds (e.g., acetaldehyde, propane, fluorocarbon, methyl acetate) .

[0046] Among different solar panel constructions, there are solutions in which the adhesive material is polyvinyl butyral (PVB) . In this case, the acetic acid formation mechanism is similar to the models described above, but the formation temperature is higher, 360-380 °C depending on heating rate, and the amount of acetic acid generated is lower. Among different backsheet configurations, processes are also known in which isotactic polypropylene (PP) is used as an alternative to PVF and PVDF-based backsheets. These polymers, under heat treatment at 550-600 °C in an inert atmosphere, undergo complete degradation with the formation of hydrogen, methane, carbon dioxide, carbon monoxide, and short- and long-chain hydrocarbons. Therefore, during thermolysis of the various polymers constituting solar panels, a reactor configuration and gas-cleaning system are required that are capable of handling the different types of by-products. For the reaction, it is important to separate any solid particles, to separate liquid and gaseous substances, and to ensure proper treatment of halogens.

[0047] Prior to commencing thermal decomposition of the coarse fraction, the 11 pyrolysis reactor vessel is positioned in the specially designed 12 thermal treatment zone. In Figure 1, for clarity, the 11 pyrolysis reactor vessel is depicted within the 12 thermal treatment zone. The 12 thermal treatment zone is a sleeve made of special thermal-insulating material, in the wall of which units suitable for heating the reactor are arranged. In the 100 solar panel processing system, multiple thermal treatment zones may be constructed simultaneously, in which several 11 pyrolysis reactor vessels can be heated, thereby ensuring continuous processing of photovoltaic panels depending on the capacity of the 7 disc mill and the saturation of the 10 unit for storing coarse fraction.

[0048] In the thermal treatment zone (12) , the coarse fraction storage unit (10) is lifted into the pyrolysis reactor vessel (11) with the aid of the apparatus moving unit, after which the lid of the pyrolysis reactor vessel (11) is secured. Once the lid of the pyrolysis reactor vessel (11) has been fastened, the necessary gas pipelines are connected to the pyrolysis reactor vessel (11) through the fittings.

[0049] Following charging and lid fixation of the 11 pyrolysis reactor vessel, its entire volume is preferably placed under a pressure of 0.025-0.1 MPa by means of vacuum pumps, in order to ensure an oxygen-free environment. For this purpose, nitrogen gas is preferably introduced into the lower part of the 11 pyrolysis reactor vessel, where the nitrogen gas flow is preferably 3.0 - 9.5 1 / min.

[0050] When the pressure inside the 11 pyrolysis reactor vessel is appropriate, the thermal treatment process may optionally be divided into two parts (pyrolysis carried out in one or two steps) , depending on the quality of the feedstock. In the following, the thermal treatment process and the processing of the various liquid and gaseous products generated are illustrated in the 100 solar panel recycling system by the example of ethylene-vinyl acetate thermolysis.

[0051] After establishing the oxygen-free environment, the 11 pyrolysis reactor vessel is heated to a peak treatment temperature of 280- 380 °C at a heating rate of 15-25 °C / min, in accordance with the decomposition mechanisms described above. The holding time is 10-50 minutes, referred to as the first stage of the thermal reaction, during which the vapor stream mainly contains acetic acid, carbon dioxide, carbon monoxide, as well as small amounts of methane, halogen compounds, and nitrogen. The gaseous product generated in the first stage is conveyed through the Ila primary technological pipeline. Through the Ila primary technological pipeline, the vapor is directed to the 14 primary dust-separating cyclone equipped with a ceramic insert, where solid particles larger than 2-10 micrometers possibly present in the gas stream are filtered out. Subsequently, the particle- and dust-free vapor is directed to the 15 primary condenser for separating liquid and gaseous substances, where the product is cooled to 80-150 ° C . At this point , condensation of acetic acid and the small amount of water present occurs , which, following separation, is conveyed through the 15a primary technological liquid pipeline into a suitable 16 primary liquid tank for further use . The gas generated in the first stage , freed from liquid and solid phases , is subsequently stored in a 17 primary gas tank, from which it is conveyed into the 27 gas-mixing unit by means of a pressure-regulating valve . This gas-mixing unit is designed so as to be capable of j ointly handling the product discharged through the I la primary technological pipeline and the 11b secondary technological pipeline , which are generated in the first and second stages of pyrolysis , respectively .

[0052] When the first stage of coarse fraction pyrolysis has been completed, under the previously described heating rate , pressure value , and nitrogen flow rate , the 11 pyrolysis reactor vessel is heated in the 12 thermal treatment zone to a temperature of 450- 650 ° C . In order for the conversion of the coarse fraction to occur to the desired extent and quality, the reactor is maintained at the peak treatment temperature for 10-50 minutes . This process is referred to as the second stage of pyrolysis , and the vapor product generated therein is conveyed through the 11b secondary technological pipeline . The gases formed during the reaction are first directed to the 18 secondary dust-separating cyclone containing a ceramic filter insert , where particles larger than 2- 10 micrometers , i . e . , solid contaminants , are filtered out . During the process , the temperature is maintained at least at 450 ° C to avoid condensation of short- and long-chain hydrocarbons present in the vapor stream . The vapor, freed from solid particles , is subsequently directed to the previously mentioned 27 gas-mixing unit , followed by a 28 ex-situ catalyst charge . As a result of the temperature conditions established in the 27 gas-mixing unit , the palladium-doped activated carbon or zeolite-based catalyst contained in the 28 ex-s itu catalyst charge promotes the further decomposition of halogen compounds at the gas temperature close to 300 ° C . Thereafter, the vapor is conveyed through the 11b secondary technological pipeline to a 19 halogen remover . The 19 halogen remover, which contains calcium, sodium, or potassium ions , is equipped with ceramic filter inserts at its inlet and outlet units . During the process , the temperature of the gas and the bed is preferably 200-300 ° C . In this stage of the process , the dissociated halogens present in the vapor stream react with the cations to form alkali-halogenide complexes , and thereby can be removed from the system . The vapor, freed from solid phases and halogens , is subsequently puri fied in the 20 secondary condenser from condensation-prone phases present in the vapor stream . The mixture separated in this process , mainly containing long carbon chains , is conveyed through the 20a secondary technological liquid pipeline into the 21 secondary liquid storage tank and stored until use . Subsequently, the puri fied gas is directed through a pressure-regulating valve into a membrane 22 gas separator, the function of which is , on the one hand, the further puri fication of the gas , as well as the separation of nitrogen present in the gas stream from the other constituents formed during the process . The permeate is conveyed through a pressure-regulating valve into the 23 secondary gas tank until further use .

[0053] The technological units described above , the 11 pyrolysis reactor vessel , the 18 secondary dust-separating cyclone , the 27 gas-mixing unit , the 28 ex-situ catalyst charge , the 19 halogen remover, the 20 secondary condenser, the 22 gas separator unit , and the 23 secondary gas tank, are interconnected through the 11b secondary technological pipeline .

[0054] I f the coarse fraction consists of polymer components whose degradation does not produce acetic acid, its thermolysis takes place in a single step, or i f processing of vapor through the I la primary technological pipel ine is not technologically j usti fied, the 100 solar panel recycling system is suitable for processing the coarse fraction generated during grinding and separation in a single stage . In this case , the vapor formed is processed through the 11b secondary technological pipeline .

[0055] In the second stage of the process illustrated, the 21 secondary liquid tank and the 23 secondary gas tank are each connected to a specially designed 20a secondary technological liquid pipeline and 23a secondary technological gas pipeline , respectively, through which these products are conveyed into the 29 electric power generating unit . In this unit , a motor capable of processing oil- and gas-phase materials is installed, which is capable of generating electric current .

[0056] Once the gaseous and liquid products generated during the previously described process have been conveyed into the appropriate storage units , thermolysis is considered complete . At this point , the connections on the reactor lid are disengaged so that the lid can be removed from the upper part of the 11 pyrolysis reactor vessel . The apparatus moving unit of the apparatus is fitted into the lugs located on the lid, and the 11 pyrolysis reactor vessel together with the lid is placed into the 13 reactor vessel cooling zone . Cooling of the 11 pyrolysis reactor vessel is assisted by unidirectional flow of ambient air . The 13 reactor vessel cooling zone is preferably designed such that the circular cross-section of the 11 pyrolysis reactor vessel fits into its interior, and the inward flow of external air is assisted by a fan installed in the lower part of the cooling zone . Once the temperature of the 11 pyrolysis reactor vessel has reached the desired 80 ° C or below, the reactor lid is dismantled through releasable screw connections , li fted of f , and placed in its designated position . Following the removal of the lid, the solid fraction remaining after thermolysis in the 10 unit for storing coarse fraction is extracted with the aid of the apparatus moving unit and poured into the storage section located at the upper part of the 24 counter-current plate dust-separating unit .

[0057] The role of the 24 counter-current plate dust-separating unit is the removal and separation of the ash, carbon formed during the pyrolysis , and the titanium dioxide remaining from the backsheet pyrolysis from the valuable raw materials in the solid phase . The solid fraction remaining after pyrolysis is fed into the upper part of the 24 counter-current plate dust-separating unit from the previously mentioned 10 unit for storing coarse fraction, and air is introduced counter-currently into the lower part of the 24 counter-current plate dust-separating unit at a flow rate preferably of 1-15 m / s . A plate mesh is inserted into the lower part of the 24 counter-current plate dust-separating unit in order to facilitate separation of fine dust fractions , where the plate spacing is 1-20 mm . The ef ficiency and quality of separation can be controlled by the plate spacing and the air flow rate .

[0058] The solid fraction separated in the 24 counter-current plate dust-separating unit is treated in the 25 wet-chemical processing unit , thereby recovering valuable raw materials . In the industry, various procedures are applied for clean and ef ficient recovery of individual elements . The illustration presented in this patent specification is one embodiment example . The first step of the wet-chemical processing process is treatment with a 1-10 wt% hydrofluoric acid solution . Treatment with hydrofluoric acid (HF) solution is suitable for selectively dissolving glass particles possibly remaining in the solid fraction, as well as the antiref lective coating on the surface of silicon cells . The use of hydrofluoric acid is further advantageous for removing the aluminum-containing layer on the rear side of the cells . The wet-chemical processing process is carried out at room temperature or at most 50 ° C, with ultrasonic agitation, which assists selective dissolution of individual raw materials . Following treatment with HF solution, the possible contaminants present in the remaining solid fraction are removed by washing with distilled water . The washing is preferably carried out three times , each time with pure distilled water, likewise with ultrasonic stirring . The cleaned solid phase , which preferably contains partially puri fied silicon cells and copper conductor ribbons , is then placed into a nitric acid solution of preferably 1-5 M concentration . As a result of the treatment with nitric acid, the silver on the surface of the cells , as well as the base materials of the conductor ribbons ( copper, tin, and lead) , enter into the solution, and at the end of the wet-chemical processing procedure the silicon cells remain, together with the aluminum-containing coating on their surface . The temperature applied during nitric acid treatment is preferably between 20-100 ° C, and ultrasonic agitation is preferably employed to facilitate the separation process . Following the treatment with the nitric acid solution, the remaining cells are cleaned by washing three times with distilled water, likewise with ultrasonic agitation . From the surface of the silicon cells , the aluminum-containing residual layer can be removed with a preferably 40-50 mass percent potassium hydroxide solution . The nitric acid solution thus contains silver, copper, tin, and lead ions , which can be recovered by selective precipitation reactions . As the first step of the recovery process , the copper is selectively dissolved from the solution with preferably 15-25 mass percent hydroxy-5-nonyl-acetophenone oxime , then, by treating with a nitric acid solution of preferably 120-150 g / 1 concentration, the copper present in the conductor ribbons can be recovered as copper sul fate . The treatment with hydroxy-5-nonyl-acetophenone oxime is advantageous because it selectively dissolves the copper and does not mix with water . In the nitric acid solution, after the removal of the copper, the silver, tin, and lead ions remain . The silver ions present in the solution can be reacted with a hydrochloric acid solution of preferably 1-5 M concentration to be separated as silver chloride . After filtering out the silver chloride , only the tin and lead ions are then present in the remaining solution, which are reacted with a sodium hydroxide solution of preferably 1-5 M concentration to be separated in the form of tin and lead hydroxide precipitate . The temperature applied during the precipitation reactions is advantageously between 20 and 100 ° C .

[0059] The further treatment of the solid-phase precipitate formed during the individual precipitation reactions may become necessary i f the metals are to be recovered in elemental form .

[0060] During the wet-chemical treatment , silicon remains in elemental form, which, through subsequent processing, can be used to produce new photovoltaic cells .

[0061] Dynamic Description of the Solar Panel Recycling System According to the Present Invention

[0062] The 100 solar panel recycling system according to the present patent operates as follows :

[0063] Solar panels of arbitrary si ze and structure are placed into the 1 solar panel storage unit , where the raw material to be processed is stored at controlled temperature . The panels are conveyed into the 2 primary disassembly unit depending on its capacity, where the aluminum frame and j unction box present on the solar panels are removed . These components are collected into the designated 3 aluminum frame storage unit and 4 j unction box storage unit . Following preliminary disassembly, the solar panels are conveyed into the 5 washing and drying unit , where they are washed and then dried . The cleaned photovoltaic panels are conveyed into the 6 secondary disassembly unit , where the panels are placed on the conveyor belt with their tempered glass side facing downward . During processing, the backsheet is cut , with the spacing of the blades determined by the diameter of the inlet opening of the 7 disc mill . In the course of secondary disassembly, the tempered glass sheet on the front side of the panels is mechanically fractured ( i f the solar panel is not already damaged) , and the cut product obtained, with a width of at least 20 mm, is collected into the 26 collection vessel . The solar panel fragments are conveyed from the 26 collection vessel through the inlet opening of the 7 disc mill into the space between the discs . The rotational speed and relative spacing of the discs are adj usted and maintained at constant values during operation . During the grinding process , the ground material falls by gravity from the lower part of the 7 disc mill onto the 8 separator, the lattice constant of which is at least 2 mm . The ground material is separated by si ze , i . e . , sieved . In the separation step, the coarse fraction ( >2 mm) —typically about 30 wt% of the initial ground amount— remaining on the mesh of the 8 separator is conveyed into the 10 unit for storing coarse fraction for further use . The particles smaller than 2 mm passing through the mesh are stored in the designated 9 unit for storing fine fraction ( the fine fraction mainly contains tempered glass ) . The 10 unit for storing course fraction containing ground material larger than 2 mm is placed into the 11 reactor vessel , which is positioned in the 12 thermal treatment zone . As a result of thermal treatment , the vapor products formed from the coarse fraction in the 11 pyrolysis reactor vessel are conveyed through the I la primary and 11b secondary technological pipelines to the respective cleaning and separation systems . The 11 pyrolysis reactor vessel together with the 10 coarse fraction storage unit is placed into the 13 reactor vessel cooling zone . In the first stage of thermal treatment (up to 330 ° C ) , the vapor formed is conveyed through the I la primary technological pipeline to the 14 primary dust-separating cyclone , from where it proceeds to the 15 primary condenser . The liquid-phase product separated in the 15 primary condenser is conveyed through the 15a primary technological liquid pipeline into the 16 primary liquid tank and stored . The gaseous product separated in the 15 primary condenser is conveyed through the I la primary technological pipeline into the 17 primary gas storage tank and stored . In the possible secondary stage of the reaction (up to 560 ° C ) , the vapor formed is conveyed through the 11b secondary technological pipeline to the 18 secondary dust-separating cyclone , from where it proceeds to the 27 gas-mixing unit . Into the 27 gas-mixing unit , the gas stored in the 17 primary gas storage tank is introduced through the I la primary technological pipeline , so that the vapor and gaseous products formed in the first and second stages of the reaction proceed together to the 28 ex-situ catalyst charge . Thereafter, the gas is conveyed to the 19 halogen remover, from where it proceeds to the 20 secondary condenser . The liquid-phase product formed in the 20 secondary condenser is conveyed through the 20a secondary technological liquid pipeline into the 21 secondary liquid tank and stored, while the gaseous product formed therein is conveyed through the 11b secondary technological pipeline into the 23 secondary gas tank and stored . The liquid stored in the 21 secondary liquid tank is conveyed through the 20a secondary technological liquid pipeline , while the gas stored in the 23 secondary gas tank is conveyed through the 23a secondary technological gas pipeline into the 29 electric power generating unit . In the 13 reactor vessel cooling zone , the 10 coarse fraction storage unit is removed from the 11 pyrolysis reactor vessel . The solid fraction contained in the 10 unit for storing coarse fraction is placed into the 24 counter-current plate dust-separating unit , from where the dust- free fraction is conveyed into the 25 wet-chemical processing unit .

[0064] Example 1. Example: recycling of a solar panel implemented with the 100 solar panel recycling system according to the invention

[0065] The operation of the 100 solar panel recycling system took place as described above with the following parameters.

[0066] Type, size, and characteristic of the subunits of the solar panel to be recycled:

[0067] - encapsulating material: ethylene-vinyl acetate copolymer (average 8.50 mass percent, in the case of one panel on average 57.80 g)

[0068] - backsheet: isotactic polypropylene (average 4.70 mass percent, in the case of one panel on average 31.96 g) front sheet: 3.20 mm thick, thermally tempered soda-lime glass (average 67.30 mass percent, in the case of one panel on average 457.64 g)

[0069] - aluminum frame (average 11.25 mass percent, in the case of one panel on average 74.90 g)

[0070] - monocrystalline silicon cell (average 2.70 mass percent, in the case of one panel on average 18.36 g)

[0071] - copper cable (average 0.78 mass percent, in the case of one panel on average 3.30 g)

[0072] - silver (average 0.04 mass percent, in the case of one panel on average 2.72 g)

[0073] - other metals (e.g. Sn, Pb) (average 0.02 mass percent, in the case of one panel on average 1.36 g)

[0074] - junction box (average 4.70 mass percent, in the case of one panel on average 31.96 g)

[0075] From the solar panel, the aluminum frame and the junction box are removed in the 2 preliminary disassembly unit, where the removal time is 3 minutes per unit.

[0076] In the 5 washing and drying unit, the washing medium is distilled water, with a washing time of at least 5 minutes. During drying, the temperature of the hot air applied is 50 ° C, with a drying time of 10 minutes .

[0077] In the 6 secondary disassembly unit , the blades used for cutting the solar panels are made of wear-resistant steel , the spacing of the blades is 20 mm, and the cutting depth from the backsheet side is 0 . 3 mm .

[0078] The 26 collection container is made of high-density polyethylene , with a volume of 550 L, in which the cut solar panels are stored .

[0079] The crushing of the cut solar panels takes place in the 7 disc mill , with the following parameters : tungsten carbide / cobalt cermet discs spaced 1 mm apart , disc rotational speed 400 revolutions per minute , grinding time 2 minutes .

[0080] In the 8 separator, the crushed material is separated into fine and coarse fractions , with the following settings of this unit : lattice constant 2 mm, separation step was carried out for 10 minutes with a vibration amplitude of 1 mm, and the metal mesh of the 8 separator was made of wear-resistant steel .

[0081] The 9 unit for storing fine fraction is made of high-density polyethylene , with a volume of 550 L ; the ignition loss of the fine fraction is 3 . 1 wt% .

[0082] The 10 unit for storing coarse fraction is made of stainless steel , with a volume of 10 L ; the ignition loss of the coarse fraction is 72 . 7 wt% .

[0083] I f 5 panels of the type presented in the example are processed, the mass of the coarse fraction conveyed into the 10 unit for storing coarse fraction is 1 kg .

[0084] The 11 pyrolysis reactor vessel has a volume of 15 L and is made of stainless steel .

[0085] The material of the 12 thermal treatment zone is a high aluminum-oxide content insulating insert , the heating insert is a wire heating element, and the set reaction temperature is 350 °C in the first step of the reaction and 550 °C in the second step of the reaction.

[0086] When the 11 pyrolysis reactor vessel is placed into the 12 thermal treatment zone, thermal treatment of the coarse fraction takes place at the above-indicated temperatures in two steps, with a reaction duration of 20 minutes in the first step and 20 minutes in the second step.

[0087] The mass of the solid fraction remaining in the 10 unit for storing coarse fraction after the first step of the reaction is 0.86 kg, and after the second step of the reaction is 0.27 kg.

[0088] The elemental composition by weight percent of the solid fraction remaining in the 10 unit for storing coarse fraction before being placed into the 24 counter-current plate dust-separating unit is as follows: carbon: 55.2%; oxygen: 29.5%; aluminum: 0.9%; silicon: 12.3%; lead: 0.1%; tin: 0.1%; titanium: 1.7%; copper: 0.2%.

[0089] The temperature of the 14 primary dust-separating cyclone is 235 °C, with a ceramic filter insert lattice constant of 20 micrometers, into which the vapor product formed in the first stage of thermal treatment is conveyed.

[0090] In the 15 primary condenser, the condensate temperature is 90 °C, where the vapor is separated into liquid and gaseous materials .

[0091] The 16 primary liquid tank is made of polytetrafluoroethylene, with a volume of 20 L, where the liquid-phase product from the separation is stored.

[0092] The 17 primary gas storage tank is made of stainless steel, with a volume of 4.5 m3, in which the gas obtained during separation is stored. The temperature of the 18 secondary dust-separating cyclone is 445 °C, with a ceramic filter insert lattice constant of 20 micrometers. Into this unit the vapor formed in the second stage of thermal treatment is conveyed.

[0093] The 27 gas-mixing unit is made of stainless steel, into which the gaseous product after separation is conveyed.

[0094] The 28 ex-situ catalyst charge has a temperature of 310 °C, the bed material being palladium-doped zeolite, through which the vapor from the 27 gas-mixing unit is passed.

[0095] That which enters the 19 halogen remover, the temperature of which is 270 °C, the reaction medium material is calcium carbonate .

[0096] The particle- and halogen-free vapor is conveyed into the 20 secondary condenser, which has a temperature of 70 °C, where the liquid and gaseous components present in the vapor are separated .

[0097] From this, the liquid-phase product is conveyed into the 21 secondary liquid tank, made of stainless steel, with a volume of 20 L .

[0098] The gaseous product is conveyed into the 22 gas separator, which has a temperature of 25 °C.

[0099] The gas is stored in the 23 secondary gas tank, made of stainless steel, with a volume of 4.5 m3.

[0100] The volumetric composition of the gas stored in the 23 secondary gas storage tank was as follows: hydrogen: 16.1%; carbon monoxide: 33.8%; methane: 16.4%; carbon dioxide: 5.6%; longer-chain hydrocarbons: 28.1%.

[0101] At the end of the thermal treatment process, the 11 pyrolysis reactor vessel is cooled in the cooling zone. The solid fraction contained in the 10 unit for storing coarse fraction is placed into the 24 counter-current plate dust-separating unit and dedusted with air at 5 m / s .

[0102] The dedusted solid fraction is conveyed into the 25 wet-chemical processing unit , where the final recovery of the elements constituting the solar panels takes place .

[0103] Reference numerals :

[0104] 1 - unit for storing solar panels

[0105] 2 - preliminary disassembly unit

[0106] 3 - unit for storing aluminum frame

[0107] 4 - unit for storing j unction box

[0108] 5 - washing and drying unit

[0109] 6 - secondary disassembly unit

[0110] 7 - disc mill

[0111] 8 - separator

[0112] 9 - unit for storing fine fraction

[0113] 10 - unit for storing coarse fraction

[0114] 11 - pyrolysis reactor vessel

[0115] I la' - primary technological pipeline outlet l ib' - secondary technological pipeline outlet

[0116] I la - primary technological pipeline

[0117] 11b - secondary technological pipeline

[0118] 12 - thermal treatment zone

[0119] 13 - reactor vessel cooling zone

[0120] 14 - primary dust-separating cyclone

[0121] 15 - primary condenser 15a - primary technological liquid pipeline

[0122] 16 - primary liquid tank

[0123] 17 - primary gas tank

[0124] 18 - secondary dust-separating cyclone 19 - halogen remover

[0125] 20 - secondary condenser

[0126] 20a - secondary technological liquid pipeline

[0127] 21 - secondary liquid tank

[0128] 22 - gas separator unit 23 - secondary gas tank

[0129] 23a - secondary technological gas pipeline

[0130] 24 - counter-current plate dust-separating unit

[0131] 25 - wet-chemical processing unit

[0132] 26 - collecting vessel 27 - gas mixing unit

[0133] 28 - ex-situ catalyst charge

[0134] 29 - electric power generating unit

[0135] 100 - solar panel recycling system

Claims

Patent Claims l. A solar panel recycling system (100) , which comprises: a unit for storing solar panels (1) ;- which is followed by a preliminary disassembly unit (2) connected with a material conveying unit, which is positioned laterally relative to the unit for storing solar panels (1) arranged at the same level; a unit for storing aluminum frame (3) , which is located below the preliminary disassembly unit (2) ; a unit for storing junction box (4) , which is positioned laterally relative to the unit for storing aluminum frame (3) ; a thermal treatment zone (12) , which is positioned laterally relative to the unit for storing coarse fraction (10) ; a reactor vessel cooling zone (13) which is located beneath the thermal treatment zone (12) ; an electric power-generating unit (29) , which is located below the secondary gas tank (23) and is connected via the secondary technological liquid pipeline (20a) with the said secondary liquid tank (21) , and through the secondary technological gas pipeline (23a) is connected to the secondary gas storage tank (23) . characterized in that the said solar panel recycling system (100) , in addition to the above, also comprises: a washing and drying unit (5) , which is positioned laterally relative to the said preliminary disassembly unit (2) and is connected thereto through a material-transfer unit ;- which is followed by a secondary disassembly unit (6) , connected with a material conveying unit, which is positioned laterally relative to the said washing and drying unit (5) ; a disc mill (7) , which is positioned laterally relative to the said secondary disassembly unit (6) ; a collection vessel (26) , which is located between the secondary disassembly unit (6) and the disc mill (7) ; a separator (8) , which is located below the disc mill (7) ; a unit for storing fine fraction (9) , which is located below the separator (8) ; unit for storing coarse fraction (10) , which is positioned in the same plane and laterally relative to the said unit for storing fine fraction (9) ; a pyrolysis reactor vessel (11) , which has a primary technological pipeline outlet (Ila' ) connected with the primary technological pipeline (Ila) , and a secondary technological pipeline outlet (lib' ) connected with the secondary technological pipeline (lib) ; a primary technological pipeline (Ila) and a secondary technological pipeline (lib) ; a primary dust-separating cyclone (14) , which is connected through the primary technological pipeline (Ila) with the said pyrolysis reactor vessel (11) and is positioned laterally relative thereto;- a primary condenser (15) , which follows the primary dust-separating cyclone (14) , is positioned laterally relative thereto, and is connected with the primary technological pipeline (Ila) ;- a primary liquid tank (16) , which is located below the primary condenser (15) and is connected thereto through the primary technological liquid pipeline (15a) ;- a primary gas tank (17) , which is positioned laterally relative to the said primary condenser (15) and connected thereto through the primary technological pipeline (Ila) ;- a secondary dust-separating cyclone (18) , which is connected through the secondary technological pipeline (11b) to the laterally positioned pyrolysis reactor vessel (11) ;- a gas-mixing unit (27) , which is connected through the secondary technological pipeline (11b) to the secondary dust-separating cyclone (18) ;- an ex-situ catalyst charge (28) , which is positioned laterally relative to the gas mixing unit (27) ;- a halogen remover (19) , which is connected through the secondary technological pipeline (11b) with the ex-situ catalyst charge (28) positioned laterally relative thereto ;- a secondary condenser (20) , which is connected through the secondary technological pipeline (11b) with the halogen remover (19) positioned laterally relative thereto;- a secondary liquid tank (21) , which is located below the secondary condenser (20) and is connected thereto through the secondary technological liquid pipeline (20a) ;- a gas separator unit (22) , positioned laterally relative to the secondary condenser (20) and connected thereto through the secondary technological pipeline (lib) ;- a secondary gas tank (23) , which is connected through the secondary technological pipeline (11b) with the gas separator unit (22) positioned laterally;- a counter-current plate dust-separating unit (24) , which follows the reactor vessel cooling zone (13) ;- which is followed by a solid fraction wet-chemical processing unit (25) , which is positioned laterally relative to the counter-current plate dust-separating unit (24) .

2. The solar panel recycling system (100) according to claim1, wherein the disc mill (7) the distance of the cutting edges exerting the shear force is between 2.0 - 0.5 mm, more preferably between 1.0 - 0.5 mm.

3. The solar panel recycling system (100) according to any of claims 1-2, wherein in the disc mill (7) the rotational speed of the grinding elements is between 200-600 rpm, more preferably between 300-500 rpm, most preferably 400 rpm.

4. The solar panel recycling system (100) according to any of claims 1-3, wherein in the disc mill (7) the material of the grinding elements is selected from the following list: aluminum oxide, tungsten carbide / cobalt cermet, most preferably the material of the grinding elements is tungsten carbide / cobalt cermet .

5. The solar panel recycling system (100) according to any of claims 1-4, wherein the metal mesh of the separator (8) is made of wear-resistant metal and has a lattice constant between 2-6 mm, preferably between 2-3 mm, most preferably 2 mm.

6. The solar panel recycling system (100) according to any of claims 1-5, wherein the mesh of the counter-current plate dust-separating unit (24) is made of wear-resistant metal and has a lattice constant between 20-1 mm, preferably between 10- 1 mm, most preferably 5 mm.

7. A process for recycling solar panels, characterized in that it comprises the following steps: a) the solar panels to be recycled are placed into the solar panel storage unit (1) ; from whereb) in the preliminary disassembly unit (2) , first the aluminum frames of the solar panels are removed, and in the second step the junction boxes located on the rear side of the panels; c) the solar panels obtained in step b) , without frame and junction box are placed into the washing and drying unit (5) , where the solar panels are cleaned and dried to constant mass; from where d) the washed and dried panels are conveyed into the secondary disassembly unit (6) , cut to a given width, the maximum distance of the cutting edges being smaller than the smallest diameter of the inlet opening of the disc mill (7) ; then e) the solar panels cut to the appropriate width are crushed in the disc mill (7) ; then f) the crushed material obtained in step e) is conveyed to the separator (8) , where the coarse and fine fractions are separated from each other and these fractions are stored in the respective units for storing the fine (9) and coarse fraction (10) ; g) from step f ) , the coarse fraction, which contains at least 50 wt% polymer, together with the unit for storing coarse fraction (10) , is placed into the pyrolysis reactor vessel (11) with the aid of an apparatus moving unit; then h) the pyrolysis reactor vessel (11) is placed into the thermal treatment zone (12) likewise with the aid of the apparatus moving unit, where the thermal treatment of the coarse fraction takes place in one step, or if necessary in two steps, wherein in the case of one step the pyrolysis temperature is between 280-380 °C, more preferably between 300-350 °C, most preferably between 310-330 °C, and in the case where pyrolysis is carried out in two steps, the thermolysis temperature is between 450-650 °C, more preferably between 500-600 °C, most preferably between 540- 560 °C, and the total duration of the heat treatment is 10-50minutes, more preferably 10-30 minutes, most preferably 10-20 minutes . i) in the first stage of the thermal treatment of step h) , the vaporous product formed is conveyed through the primary technological pipeline (Ila) to the primary dust-separating cyclone (14) ; from where j) from step i) , the vapor is separated in the primary condenser (15) into liquid and gaseous substances, where the temperature of the primary condenser is between 80-150 °C, more preferably between 80-120 °C, most preferably between 80-110 °C; then j' ) the liquid formed during separation of step j) is stored in the designated primary liquid tank (16) , while the gas formed during step j ) is conveyed through a pipeline into the primary gas storage tank (17) ; or j") in the case where the thermolysis temperature exceeds 450 °C, the vaporous product formed is conveyed through the secondary technological pipeline (11b) to the secondary dust-separating cyclone (18) , from where the gas is conveyed to the gas mixing unit (27) , into which the gas stored in the primary gas tank (17) is introduced through the primary technological pipeline (Ila) , in the case when it is necessary to carry out the first step as well; from where k) the particle- and halogen-free vapor is conveyed to the secondary condenser (20) , where the liquid and gaseous components present in the vaporous product are separated; l) then the liquid-phase product formed in step k) is conveyed into the secondary liquid tank (21) and stored; m) the gaseous-phase product separated during step k) is conveyed to the gas separator unit (22) ; then conveyed into the secondary gas tank (23) and stored;n) during the condensation process of step k) , the liquid present in the secondary liquid storage tank (21) (step 1) ) through the secondary technological liquid pipeline (20a) and the gas stored in the secondary gas storage tank (23) (step m) through the secondary technological gas pipeline (23a) are conveyed into the electric power generating unit (29) ; o) upon completion of the thermal treatment process of step h) , the pyrolysis reactor vessel (11) is placed into the reactor vessel cooling zone (13) with the aid of the apparatus moving unit, where the pyrolysis reactor vessel (11) is cooled to 80 °C or below; then p) after cooling of the pyrolysis reactor vessel (11) , the reactor cover is removed and with the aid of the device moving unit the unit for storing coarse fraction (10) is lifted out, which contains the solid fraction remaining after the thermolysis; from where q) the solid fraction contained in the unit for storing coarse fraction (10) is placed into the counter-current plate dust-separating unit (24) , where the air flow velocity is between 1-15 m / s, more preferably between 1-10 m / s, most preferably between 1-5 m / s; from where r) the dust-free solid fraction obtained in step q) is conveyed into the wet chemical processing unit (25) , where the final recovery of the elements constituting the solar panels takes place .

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