Waste photovoltaic panel pyrolysis chain panel kiln with waste gas recycling
Patent Information
- Application Number
- CN202522770737.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-26
- Publication Date
- 2026-10-09
- Estimated Expiration
- 2035-12-26
AI Technical Summary
[0003]现有热解设备存在两大痛点：一是能耗高热解需要持续供热，而可燃废气通常直接点燃排放或经复杂净化后排放，其蕴含的化学能和热能未被有效利用
[0009]本实用新型的有益效果在于：通过在加热段下部设置的隔焰板将炉膛分隔为两个独立的空间，上部通过电加热管加热，下部则引入焚烧炉回流烟气，共同构成废光伏板热解的热源。由于采用了“废气焚烧，能量回用”的内循环系统，通过焚烧炉将热解产生的胶气进行焚烧，焚烧后的高温烟气又作为热解的部分热源，实现了废气的无害化处理与能量的闭环利用；同时在进料口和出料口分别设置一套气幕装置，并将窑炉系统本身排放的部分低温废气作为气幕气源，喷入形成气幕。该气幕能有效隔绝外部空气渗入和内部气氛外泄，且气源本身为低氧烟气，所以能维持热解段低氧环境，同时实现了废气的二次利用。具有节能降耗、环保高效、运行成本低、热解效果好的显著优点，为废旧光伏板热解回收有用成分提供了优质高效的热工设备，市场前景十分广阔。
Smart Images
Figure CN224837406U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to waste photovoltaic module recycling and processing technology, specifically to a waste photovoltaic panel pyrolysis chain kiln with waste gas recycling function. Background Technology
[0002] Pyrolysis is a key pretreatment technology for recycling valuable components (metals) from waste photovoltaic panels. It involves heating the encapsulation materials, such as EVA, to pyrolyze them, thus separating the layers. Ideally, pyrolysis should be carried out in an oxygen-free or low-oxygen environment to prevent the combustion of organic matter and the oxidation of metals, which would affect the quality of the recycled product.
[0003] Existing pyrolysis equipment suffers from two major drawbacks: First, it is energy-intensive, requiring continuous heating for pyrolysis. Combustible waste gases are typically either directly ignited or released after complex purification processes, resulting in the ineffective utilization of their chemical and thermal energy. Second, atmosphere control is difficult and costly. The uncontrolled inert atmosphere within the kiln often leads to open flames, significantly impacting the quality of the recovered products.
[0004] Therefore, developing a pyrolysis equipment that can achieve energy self-circulation and low-cost precise control of oxygen content is crucial for reducing the cost of photovoltaic panel recycling and promoting industrialization. Utility Model Content
[0005] The present invention aims to overcome the above-mentioned defects and provide an energy-saving, environmentally friendly waste photovoltaic panel pyrolysis chain kiln and method that can stably maintain a low-oxygen environment.
[0006] The technical solution of this utility model is as follows: a waste photovoltaic panel pyrolysis chain kiln for waste gas recycling includes a kiln body, a chain conveyor system, a heating system, and a pyrolysis gas treatment system, etc. The kiln body is divided into a heating section, a heat preservation section, and a cooling section. Flame baffles are installed below the chain conveyors in the heating and heat preservation sections of the kiln body. Electric heating tubes are installed at the top of the furnace, and a pyrolysis gas treatment system is installed on the kiln body. This pyrolysis gas treatment system includes an incinerator, a combustion fan, a plate heat exchanger, a high-temperature circulating fan, and ductwork, etc. A heat extraction duct is installed on the top of the kiln in the heat preservation section and connected to the incinerator. The gel gas generated after the waste photovoltaic panels in the furnace are pyrolyzed is drawn into the incinerator for combustion by the high-temperature circulating fan. The plate heat exchanger is located below the kiln roof in the front half of the cooling section. The air inlet is connected to the combustion fan via a duct. The hot air outlet is divided into two paths via a duct: one path is connected to the combustion air inlet of the incinerator burner, and the other path is sent in groups to the upper space of the flame baffle (6) in the heating section and the insulation section. The exhaust port of the high-temperature circulating fan is connected to the exhaust port of the incinerator via a duct. The high-temperature flue gas after combustion is sent in groups to the lower space of the flame baffle in the insulation section as a supplementary heat source. A waste exhaust duct is also installed on the kiln roof in front of the heating section and connected to the waste exhaust fan.
[0007] Furthermore, air curtain devices are installed at the feed and discharge ends of the kiln body. These air curtain devices are annular ducts arranged circumferentially along the cross-section of the feed or discharge port. Multiple injection holes facing inwards are opened on the annular ducts. The air source is introduced through a pipeline connected to the exhaust fan, allowing a portion of the low-temperature waste gas emitted by the kiln system itself to form an isolation air curtain at the feed and discharge ports. This system innovatively utilizes the system's own waste gas as a sealing medium. Annular air curtain nozzles are installed at the kiln head (feed end) and kiln tail (discharge end). The low-temperature waste gas generated within the kiln system, which has no further utilization value, is injected as the air source for the air curtain, forming a stable gas curtain. This air curtain effectively blocks the free exchange of gases inside and outside the kiln, preventing external air from entering and disrupting the pyrolysis atmosphere, while also reducing the escape of gases from inside the kiln. This solution achieves two goals: firstly, it achieves efficient dynamic sealing; secondly, it reuses the waste gas to be discharged, eliminating the need for fresh nitrogen and significantly reducing the cost of protective gas.
[0008] Furthermore, a plate heat exchanger is installed at the upper part of the front section of the cooling section, and finned water-cooled pipes are installed above and below the chain conveyor device at the rear section.
[0009] The beneficial effects of this invention are as follows: By dividing the furnace into two independent spaces through a flame-insulating plate installed at the bottom of the heating section, the upper space is heated by electric heating tubes, while the lower space introduces flue gas from the incinerator, together forming the heat source for the pyrolysis of waste photovoltaic panels. Due to the adoption of an internal circulation system of "waste gas incineration and energy recovery," the incinerator incinerates the gel-like gases produced during pyrolysis, and the high-temperature flue gas after incineration serves as part of the heat source for pyrolysis, achieving harmless treatment of waste gas and closed-loop utilization of energy. Simultaneously, an air curtain device is installed at both the inlet and outlet, using a portion of the low-temperature waste gas emitted by the kiln system itself as the air source for the air curtain. This air curtain effectively isolates external air infiltration and internal atmosphere leakage, and since the air source itself is low-oxygen flue gas, it maintains a low-oxygen environment in the pyrolysis section, while also achieving secondary utilization of waste gas. It has significant advantages such as energy saving and consumption reduction, environmental friendliness and high efficiency, low operating costs, and good pyrolysis effect, providing high-quality and efficient thermal equipment for the pyrolysis recovery of useful components from waste photovoltaic panels, with a very broad market prospect.
[0010] The following structural drawings further illustrate this utility model. Attached Figure Description
[0011] Figure 1 This is a schematic diagram of the system structure of the chain plate kiln of this utility model; Figure 2 This is a schematic diagram of the cross-section of the chain plate kiln insulation section of this utility model; Figure 3 This is a schematic diagram of the cross-section of the cooling section of the chain plate kiln of this utility model; Figure 4This is a schematic diagram of the air curtain device at the inlet and outlet ends of the chain plate kiln of this utility model.
[0012] In the diagram: 1. Feeding end, 2. Discharge end, 3. Heating section, 4. Insulation section, 5. Cooling section, 6. Flame baffle, 7. Electric heating tube, 8. Incinerator, 9. Air curtain device, 10. Chain plate, 11. Combustion fan, 12. Waste exhaust fan, 13. Finned water-cooled tube, 14. Plate heat exchanger, 15. High-temperature circulating fan. Detailed Implementation
[0013] like Figure 1As shown, the waste photovoltaic panel pyrolysis chain kiln for waste gas recycling consists of a kiln body, a chain conveyor system, a heating system, and a pyrolysis gas treatment system. The kiln body is typically divided into a heating section 3, a heat preservation section 4, and a cooling section 5. Flame baffles 6 are installed below the chain plates 10 of the chain conveyor system in the heating section 3 and heat preservation section 4. Electric heating tubes 7 are installed at the top of the furnace, and a pyrolysis gas treatment system is installed on the kiln body. This pyrolysis gas treatment system includes an incinerator 8, a combustion fan 11, a plate heat exchanger 14, a high-temperature circulating fan 15, and ductwork. A heat extraction duct is installed on the top of the heat preservation section 4 and connected to the incinerator 8. The plate heat exchanger 14 is located below the top of the kiln in the first half of the cooling section 5. Its air inlet is connected to the combustion fan 11 via a duct, and the hot air outlet is divided into two paths via a duct: one path connects to the combustion air inlet of the burner in the incinerator 8, and the other path is sent in groups to the space above the flame baffles 6 in the heat preservation section 4. The exhaust port of the high-temperature circulating fan 15 is connected to the exhaust port of the incinerator 8 via a duct. The high-temperature flue gas after combustion is grouped and sent into the space below the flame baffle 6 of the insulation section 4 as a supplementary heat source. A waste exhaust duct is also installed on the kiln top in front of the heating section 3 and connected to the waste exhaust fan 12. In order to prevent external air from entering the furnace and disrupting the pyrolysis atmosphere, and to reduce the escape of gas inside the kiln, air curtain devices 9 are respectively installed at the feed end 1 and the discharge end 2 of the kiln body. The air curtain device 9 is an annular duct arranged circumferentially along the cross-section of the feed inlet or discharge outlet. The annular duct has multiple injection holes facing the inside of the channel. The air source is introduced through a pipe connected to the waste exhaust fan 12, so that some of the low-temperature waste gas emitted by the kiln system itself forms an isolation air curtain at the feed inlet and discharge outlet. This air curtain can effectively prevent external air from seeping in and internal atmosphere from leaking out. Moreover, the air source itself is low-oxygen flue gas, so it can maintain a low-oxygen environment in the pyrolysis section and realize the secondary utilization of waste gas. A plate heat exchanger 14 is installed at the upper part of the front section of the cooling section 5, and finned water-cooled pipes 13 are installed above and below the conveying device of the chain plate 10 at the rear section. In implementing this invention, nitrogen is first introduced into the kiln, and the air curtain device 9 is activated. The exhaust fan 12 draws out the exhaust gas below the flame-insulating plate 6, and part of it is transported to the air curtain devices 9 at the kiln head and tail, where it is sprayed towards the inlet and outlet to form a stable air curtain. The combustion fan 11 sends the combustion air through the plate heat exchanger 14 to the incinerator 8, and another part is sent in groups to the upper space of the flame-insulating plate 6 in the heating section (heating section 3 and heat preservation section 4). Waste photovoltaic panels are continuously fed from the kiln head 1 and conveyed by the chain plate 10. In the heating section 3 and heat preservation section 4, the electric heating pipes 7 above the flame-insulating plate 6 provide the main heat source, while the high-temperature flue gas provided by the incinerator 8 below the flame-insulating plate 6 serves as the heat source. The high-temperature viscous gas generated in the upper part of the insulation section 4 enters the incinerator 8 through the furnace top exhaust pipe for incineration to produce high-temperature flue gas, which is then introduced to the area below the flame baffle 6 in the constant temperature section by the high-temperature circulating fan 15 as a supplementary heat source. After pyrolysis, the solid residue is cooled in the cooling section 5 by the plate heat exchanger 14 and the finned water-cooled pipe 13 and then discharged from the kiln tail 2.
[0014] The above embodiments fully demonstrate the feasibility and superiority of this utility model. Through ingenious system integration, this utility model combines environmental protection treatment, energy recovery, and process assurance, providing an innovative solution for the large-scale, low-cost recycling of waste photovoltaic panels.
Claims
1. A waste photovoltaic panel pyrolysis chain kiln for waste gas recycling, comprising a kiln body, a chain conveying system, a heating system, and a pyrolysis gas treatment system, wherein the kiln body is divided into a heating section (3), a heat preservation section (4), and a cooling section (5), characterized in that: Flame baffles (6) are installed below the chain conveyor system (10) of the heating section (3) and insulation section (4) of the kiln body. Electric heating tubes (7) are installed at the top of the furnace. A pyrolysis gas treatment system is installed on the kiln body. The pyrolysis gas treatment system includes an incinerator (8), a combustion blower (11), a plate heat exchanger (14), a high-temperature circulating blower (15), and air ducts. A heat extraction air duct is installed on the top of the kiln body insulation section (4) and connected to the incinerator (8). The plate heat exchanger (14) is installed below the top of the kiln body in the first half of the cooling section (5). The air inlet is connected to the combustion blower (11) through the air duct. The hot air outlet is divided into two paths through the air duct: one path is connected to the combustion air inlet of the burner of the incinerator (8), and the other path is sent in groups to the upper space of the flame baffles (6) of the heating section (3) and insulation section (4). The exhaust port of the high-temperature circulating fan (15) is connected to the exhaust port of the incinerator (8) through the air duct. The high-temperature flue gas after combustion is sent in groups to the lower space of the flame baffle (6) of the heat preservation section (4) as a supplementary heat source. A waste exhaust duct is also installed on the kiln top in front of the heating section (3) and connected to the waste exhaust fan (12).
2. The waste photovoltaic panel pyrolysis chain kiln for waste gas recycling according to claim 1, characterized in that: An air curtain device (9) is provided at the feed end (1) and discharge end (2) of the kiln body. The air curtain device (9) is an annular air duct arranged circumferentially along the cross section of the feed inlet or discharge outlet. Multiple injection holes facing the inside of the channel are opened on the annular air duct. The air source is introduced through a pipeline connected to the exhaust fan (12) so that some of the low-temperature exhaust gas emitted by the kiln system itself forms an isolation air curtain at the feed inlet and discharge outlet.
3. The waste photovoltaic panel pyrolysis chain kiln for waste gas recycling according to claim 1 or 2, characterized in that: The cooling section (5) has a plate heat exchanger (14) installed at the upper part of the front section and finned water cooling pipes (13) installed above and below the chain plate (10) conveying device at the rear section.