A pyrolysis method for battery recycling

Abstract

The application relates to a battery recycling pyrolysis method based on a battery pyrolysis device, which comprises a pyrolysis kiln containing a casing and a pyrolysis furnace body; a front exhaust assembly containing an exhaust pipe connected to a feeding channel of the pyrolysis furnace body, the exhaust pipe being sequentially connected with a physical filtering device, a fire-retardant container and a pyrolysis gas combustion furnace; a closing plate is arranged outside the gas inlet end of the fire-retardant container through an elastic element, and the closing plate is fixed by a pull assembly made of combustible materials; the battery recycling pyrolysis method comprises the following specific steps: S1, after the broken battery scraps are subjected to high-temperature anaerobic pyrolysis through the pyrolysis furnace body, the pyrolysis tail gas is collected and discharged; S2, the high-temperature pyrolysis tail gas enters the physical filtering device through the exhaust pipe; S3, after the tail gas filtered through the physical filtering device is discharged into the fire-retardant container, the tail gas is burned in the pyrolysis gas combustion furnace. The application can realize front discharge of the pyrolysis tail gas, thereby effectively reducing the doping amount of volatile substances in the pyrolysis material.

Description

Technical Field

[0001] This invention relates to the technical field of equipment for battery crushing and recycling, specifically to a pyrolysis method for battery recycling, which can pyrolyze crushed battery materials while ensuring safety. Background Technology

[0002] Waste lithium batteries contain electrolytes (such as lithium hexafluorophosphate), separators (polyolefins), and binders (PVDF). These organic components remain attached to the electrode material surface even after crushing. Therefore, the crushed battery fragments need to undergo pyrolysis treatment to lay the foundation for the subsequent high-purity recovery of metal resources.

[0003] Currently, the pyrolysis process of crushed battery fragments mainly involves completely breaking down organic matter into combustible gases (methane, hydrogen, etc.) in a high-temperature, oxygen-free environment (500–650℃). These combustible gases are then purified through secondary combustion before being released, avoiding environmental pollution. Existing battery pyrolysis equipment primarily concentrates its exhaust gas emissions at the discharge end. During this concentrated emission, some volatile substances in the exhaust gas can easily become mixed with the material and enter the discharge. In the subsequent cooling process, these substances will re-condense and adhere to the battery fragments, thus affecting the purity of the recovered metal resources.

[0004] To improve the purity of subsequently recycled metal resources, some waste battery recycling and processing plants have begun to try moving the emission location of battery pyrolysis exhaust gas forward to the front of the battery pyrolysis equipment, i.e., the feed end side. However, since the pyrolysis process of the battery fragments located on the feed end side of the battery pyrolysis equipment has only just begun, when the pyrolysis exhaust gas is discharged from the feed end side of the battery pyrolysis equipment, it is easy to carry some incompletely pyrolyzed small particles (dust and grease) along with it. This not only greatly increases the difficulty of exhaust gas treatment, but may also cause open flames during secondary combustion to ignite at the exhaust end, resulting in safety accidents. As a result, the battery recycling pyrolysis process set up for pre-emission of pyrolysis exhaust gas is difficult to implement effectively.

[0005] Therefore, the research objective of this invention is to design a battery recycling pyrolysis method that can achieve pre-emission of pyrolysis exhaust gas while effectively ensuring the safety of exhaust gas treatment, thereby effectively reducing the amount of volatile substances in the pyrolysis material and helping to improve the purity of subsequent metal resource recovery. Summary of the Invention

[0006] In view of the technical problems existing in the prior art, the present invention provides a pyrolysis method for battery recycling, which can effectively solve the technical problems existing in the prior art.

[0007] The technical solution of this invention is: A battery recycling pyrolysis method, based on a battery pyrolysis apparatus, the battery pyrolysis apparatus comprising: A pyrolysis kiln includes a casing and a pyrolysis furnace body rotatably installed inside the casing. A feed channel extending to the feed end of the pyrolysis furnace body is installed on one side of the casing. The feed channel is provided with feed inlets and exhaust outlets at intervals. A collection container connected to the discharge end of the pyrolysis furnace body is installed on the other side of the casing. A corresponding discharge outlet is provided at the lower end of the collection container. The front exhaust assembly includes an exhaust pipe connected to the exhaust port of the feed channel, the exhaust pipe being connected to the inlet of a corresponding physical filter, the outlet of the physical filter being connected to the inlet of a corresponding flame-retardant container, and the outlet of the flame-retardant container being connected to the inlet of a corresponding pyrolysis gas combustion furnace; a corresponding closing plate is provided on the outside of the inlet of the flame-retardant container by a corresponding elastic element, and the side of the closing plate not connected to the elastic element is fixed by a traction assembly made of combustible material, so that the elastic element is set in a tensioned state, and the traction assembly is fixedly connected to the outlet of the flame-retardant container. The battery recycling pyrolysis method includes the following specific steps: S1, the crushed battery fragments are transported by an external lifting mechanism and enter the pyrolysis furnace through the feeding channel. The material is conveyed from the feeding end to the discharge end of the pyrolysis furnace for high-temperature oxygen-free pyrolysis, and then collected and discharged through the pyrolysis furnace. S2, the exhaust gas generated by high-temperature pyrolysis enters the physical filtration device through the exhaust pipe of the front exhaust assembly for particulate matter filtration. S3, the exhaust gas filtered by the physical filtration device is discharged into the pyrolysis gas combustion furnace after passing through the flame-retardant container for combustion. When the combustion flame of the pyrolysis gas combustion furnace extends in the opposite direction into the interior of the flame-retardant container, the pulling component is burned off, and the closing plate forms a seal on the air inlet of the flame-retardant container under the elastic force of the elastic element.

[0008] The pulling assembly includes several pulling ropes arranged in a ring array. One end of each pulling rope is fixed to the back of the closing plate, and the other end of each pulling rope is fixed to the gas outlet of the flame-retardant container. The middle part of each pulling rope passes through a fixing hole on the outer side of the corresponding ring plate.

[0009] The pulling rope is made of one of nylon rope, polyester rope, or polypropylene rope, and the annular plate is fixed to the flame-retardant container by a corresponding connecting rod.

[0010] A pressure sensor is installed on the exhaust pipe. In step S3, when the combustion flame of the pyrolysis gas combustion furnace extends in the opposite direction into the flame-retardant container, the pulling rope of the pulling assembly is burned off. The closing plate forms a seal on the air inlet of the flame-retardant container under the elastic force of the elastic element. At this time, the pressure sensor detects the increase in gas pressure in the exhaust pipe and sends a signal to the corresponding electrical controller to issue an alarm.

[0011] The battery pyrolysis equipment also includes an explosion-proof component, which includes a pressure relief pipe connected to the upper end of the collection container. The exhaust end of the pressure relief pipe is connected to a corresponding water-containing cavity. The water-containing cavity is filled with water-sealing liquid at a level higher than the exhaust end of the pressure relief pipe. A corresponding liquid distribution groove is fitted around the periphery of the water-containing cavity. Several guide holes are provided on the water-containing cavity facing the bottom side of the liquid distribution groove. Isolation ceramic plates are sealed and installed at the guide holes respectively. The liquid distribution groove is filled with corresponding spare water-sealing liquid. In step S1, when an explosion occurs in the pyrolysis furnace due to excessive accumulation of electrolyte solvent volatiles, the explosion shock wave is discharged along the pressure relief pipe. The explosion shock wave shatters the isolation ceramic plates, making the guide holes open, so that the spare water-sealing liquid can be promptly introduced into the water-containing cavity after the explosion to re-seal the pressure relief pipe.

[0012] An oil trap is installed on the exhaust pipe. The exhaust pipe includes a horizontal exhaust section, and the two ends of the horizontal exhaust section are respectively connected to the exhaust port of the feed channel and the air inlet of the physical filter through corresponding conduits. The oil trap includes an oil trapping spiral plate rotatably installed on the horizontal exhaust section of the exhaust pipe. The oil trapping spiral plate is driven to the output shaft of a corresponding oil trapping drive motor through a corresponding transmission shaft. In step S2, the oil trapping drive motor drives the oil trapping spiral plate to rotate to capture oil particles in the exhaust gas flowing through the exhaust pipe and transport the captured oil back to the feed channel for further pyrolysis.

[0013] The pyrolysis furnace body is evenly equipped with multiple inclined tipping plates for pushing materials from the feed end to the discharge end, and the pyrolysis furnace body is driven by a corresponding furnace body drive mechanism.

[0014] The furnace body drive mechanism includes an external gear ring rotatably disposed at the end of the pyrolysis furnace body, and a drive gear meshing with the external gear ring. The drive gear is connected to the output shaft end of the corresponding furnace body drive motor through a corresponding connecting shaft.

[0015] The casing is equipped with a heater for heating the pyrolysis furnace body, and the heater is an electric heater.

[0016] The physical filtration device uses a bag filter dust collector.

[0017] Compared with the prior art, the advantages and positive effects of the present invention are as follows: 1) In the pre-exhaust assembly of this invention, in addition to the physical filtration device and the pyrolysis gas combustion furnace, a flame-retardant container is also added. Most importantly, this invention further provides a closing plate on the outside of the gas inlet end of the flame-retardant container via an elastic element. The side of the closing plate not connected to the elastic element is fixed by a flammable tensioning component, keeping the elastic element in a tensioned state. During the pyrolysis process, the crushed battery fragments are collected and discharged after high-temperature anaerobic pyrolysis in the pyrolysis furnace. The exhaust gas generated by the high-temperature pyrolysis enters the physical filtration device through the exhaust pipe of the pre-exhaust assembly for particulate matter filtration, then passes through the flame-retardant container and is discharged into the pyrolysis gas combustion furnace for combustion. When the combustion flame of the pyrolysis gas combustion furnace extends in the opposite direction into the interior of the flame-retardant container, the tensioning component is burned off, causing the closing plate to seal the gas inlet end of the flame-retardant container under the elastic force of the elastic element. In this way, the backflow of open flame can be completely isolated, achieving pre-emission of pyrolysis exhaust gas while ensuring the safety of exhaust gas treatment. This effectively reduces the amount of volatile substances mixed in with the pyrolysis material, thus helping to improve the purity of subsequent metal resource recovery.

[0018] 2) The pulling assembly of the present invention includes a plurality of pulling ropes arranged in a ring array. One end of each pulling rope is fixed to the back of the closing plate and the other end is fixed to the gas outlet of the flame-retardant container. The middle part of each pulling rope passes through the fixing hole on the outer side of the corresponding ring plate. With the intervention of the ring plate, the pulling ropes arranged in a ring array are dispersed, so as to effectively increase the burn-off probability of the pulling assembly while maintaining sufficient pulling force. This ensures both the pulling effect on the closing plate and the timely burn-off of the pulling assembly when an open flame enters the flame-retardant container, thus ensuring the practical effect of the present invention.

[0019] 3) The exhaust pipe of the present invention is equipped with a corresponding pressure sensor. When the pull rope is burned off and the closing plate forms a seal on the air inlet of the flame-retardant container under the elastic force of the elastic element, the pressure sensor can detect the increase in air pressure in the exhaust pipe in time and transmit the signal to the corresponding electric controller to issue an alarm, thereby further assisting in improving the operational safety of pre-emission of pyrolysis tail gas.

[0020] 4) This invention also includes an explosion-proof component, comprising a pressure relief pipe connected to the upper end of the collection container. The vent end of the pressure relief pipe is connected to a corresponding water-containing cavity, and the water-containing cavity is filled with a water-sealing liquid at a level higher than the vent end of the pressure relief pipe. Most importantly, a corresponding liquid distribution groove is fitted around the periphery of the water-containing cavity. Several guide holes are provided on the water-containing cavity facing the bottom of the liquid distribution groove, and isolation ceramic plates are sealed and installed at each guide hole. The liquid distribution groove is filled with a corresponding spare water-sealing liquid. This is because the volatile solvents from the electrolyte produced by pyrolysis are flammable and explosive. If an explosion occurs due to excessive accumulation of volatile electrolyte solvents, the explosion shock wave can be discharged along the pressure relief pipe to reduce explosion losses. The shock wave generated by the explosion is effectively dissipated when it impacts the water seal liquid, and the shock wave will shatter the isolation ceramic plate, thereby keeping the guide hole in a connected state so that the spare water seal liquid can be introduced into the water containment cavity in time after the explosion, to prevent the continuous large-scale discharge of pyrolysis tail gas after the explosion, which would exacerbate the severity of the safety accident.

[0021] 5) The exhaust pipe of the present invention is equipped with an oil trap. The horizontal exhaust section of the exhaust pipe allows the pyrolysis tail gas to flow smoothly. Then, the rotation of the oil trap spiral plate increases the contact rate between the airflow and the oil trap spiral plate, so that small oil particles in the airflow can be effectively attached to the oil trap spiral plate and enriched. Under the transmission action of the oil trap spiral plate, the enriched oil is reversed and transported back into the feed channel and re-enters the pyrolysis furnace for pyrolysis. This effectively reduces the amount of small dust and grease entrained in the front exhaust, further enhancing the safety of the front exhaust system. Attached Figure Description

[0022] Figure 1 This is a flow chart of the pyrolysis process of the present invention.

[0023] Figure 2 This is a schematic diagram of the battery pyrolysis device of the present invention.

[0024] Figure 3 This is a diagram showing the usage state of the battery pyrolysis device of the present invention.

[0025] Figure 4 This is a schematic diagram of the pyrolysis kiln of the present invention.

[0026] Figure 5 This is a schematic diagram of the explosion-proof component of the present invention.

[0027] Figure 6 This is a schematic diagram of the structure of the flame-retardant container of the present invention.

[0028] Figure 7 This is a schematic diagram of the oil sludge collector of the present invention.

[0029] In the attached diagram: 1. Cracking kiln; 101. Casing; 102. Cracking furnace body; 103. Feed channel; 104. Collection container; 2. Explosion-proof component; 201. Pressure relief pipe; 202. Water container; 203. Water seal liquid; 204. Liquid distribution tank; 205. Isolation ceramic plate; 206. Backup water seal liquid; 3. Front exhaust component; 301. Exhaust pipe; 301. Horizontal exhaust section; 3012. Conduit; 302. Physical filtration device; 303. Flame retardant container; 4. Cracking gas combustion furnace; 5. Elastic component; 6. Closing plate; 7. Pulling component; 701. Pulling rope; 702. Ring plate; 8. Pressure sensor; 9. Oil trap; 901. Oil trap spiral plate; 902. Drive shaft; 903. Oil trap drive motor; 10. Inclined tipping plate; 1101. External gear ring; 1102. Drive gear; 1103. Drive shaft; 1104. Furnace body drive motor; 12. Heater. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0031] refer to Figure 1-7 A battery recycling pyrolysis method, based on a battery pyrolysis apparatus comprising: The pyrolysis kiln 1 includes a casing 101 and a pyrolysis furnace body 102 rotatably installed inside the casing 101. A feed channel 103 extending to the feed end of the pyrolysis furnace body 102 is installed on one side of the casing 101 (in this embodiment, a corresponding feeding auger is provided in the feed channel 103). The feed channel 103 is provided with feed inlets and exhaust outlets at intervals. A collection container 104 connected to the discharge end of the pyrolysis furnace body 102 is installed on the other side of the casing 101. A corresponding discharge outlet is provided at the lower end of the collection container 104. The front exhaust assembly 3 includes an exhaust pipe 301 connected to the exhaust port of the feed channel 103. The exhaust pipe 301 is connected to the air inlet of the corresponding physical filter 302. The air outlet of the physical filter 302 is connected to the air inlet of the corresponding flame-retardant container 303. The air outlet of the flame-retardant container 303 is connected to the air inlet of the corresponding pyrolysis gas combustion furnace 4. A corresponding closing plate 6 is provided on the outside of the air inlet of the flame-retardant container 303 by a corresponding elastic member 5. The side of the closing plate 6 not connected to the elastic member 5 is fixed by a flammable tensioning assembly 7, so that the elastic member 5 is set in a tensioned state. The tensioning assembly 7 is fixedly connected to the air outlet of the flame-retardant container 303. The battery recycling pyrolysis method includes the following specific steps: S1, the crushed battery fragments are transported by an external lifting mechanism (auger lifting machine) through the feeding channel 103 into the pyrolysis furnace body 102. The material is conveyed from the feeding end to the discharge end of the pyrolysis furnace body 102 for high-temperature oxygen-free pyrolysis, and then collected and discharged through the pyrolysis furnace body 102. S2, the exhaust gas generated by high-temperature pyrolysis enters the physical filter device 302 through the exhaust pipe 301 of the front exhaust assembly 3 for particulate matter filtration. S3, the exhaust gas filtered by the physical filter device 302 passes through the flame-retardant container 303 and is then discharged into the pyrolysis gas combustion furnace 4 for combustion. When the combustion flame of the pyrolysis gas combustion furnace 4 extends in the opposite direction into the interior of the flame-retardant container 303, the pulling component 7 is burned off, and the closing plate 6 forms a seal on the air inlet end of the flame-retardant container 303 under the elastic force of the elastic element 5.

[0032] In the front exhaust assembly of this invention, in addition to the physical filter device 302 and the pyrolysis gas combustion furnace 4, a flame-retardant container 303 is also provided. Most importantly, this invention further provides a closing plate 6 on the outside of the air inlet end of the flame-retardant container 303 by means of an elastic member 5. The side of the closing plate 6 not connected to the elastic member 5 is fixed by a flammable tensioning component 7, so that the elastic member 5 is set in a tensioned state. During the pyrolysis process, the broken battery fragments are collected and discharged after being subjected to high-temperature anaerobic pyrolysis in the pyrolysis furnace body 102. The exhaust gas generated by the high-temperature pyrolysis enters the physical filter device 302 through the exhaust pipe 301 of the front exhaust assembly 3 for particulate matter filtration, and then passes through the flame-retardant container 303 before being discharged into the pyrolysis gas combustion furnace 4 for combustion. When the combustion flame of the pyrolysis gas combustion furnace 4 extends in the opposite direction into the interior of the flame-retardant container 303, the tensioning component 7 is burned off, so that the closing plate 6, driven by the elastic force of the elastic member 5, seals the air inlet end of the flame-retardant container 303. In this way, the backflow of open flame can be completely isolated, so as to achieve the pre-emission of pyrolysis tail gas while ensuring the safety of tail gas treatment. This effectively reduces the amount of volatile substances in the pyrolysis material, thereby helping to improve the purity of subsequent metal resource recovery.

[0033] The pulling assembly 7 includes a plurality of pulling ropes 701 arranged in a ring array. One end of each pulling rope 701 is fixed to the back of the closing plate 6, and the other end of each pulling rope 701 is fixed to the gas outlet of the flame-retardant container 303. The middle part of each pulling rope 701 is installed through a fixing hole on the outer side of the corresponding ring plate 702.

[0034] The pulling rope 701 is made of nylon, polyester, or polypropylene, and the annular plate 702 is fixed to the flame-retardant container 303 via a corresponding connecting rod. In this embodiment, the pulling rope 701 is made of nylon.

[0035] The pulling component 7 of the present invention includes a plurality of pulling ropes 701 arranged in a ring array. With the intervention of the ring plate 702, the pulling ropes 701 arranged in a ring array are dispersed, so as to effectively increase the burn-off probability of the pulling component 7 while maintaining sufficient pulling force. This ensures both the pulling effect on the closing plate 6 and the timely burn-off of the pulling component 7 when an open flame enters the flame-retardant container 303, thus ensuring the practical effect of the present invention.

[0036] A pressure sensor 8 is installed on the exhaust pipe 301. In step S3, when the combustion flame of the pyrolysis gas combustion furnace 4 extends in the opposite direction into the flame-retardant container 303, the pulling rope 701 of the pulling assembly 7 is burned off. The closing plate 6 forms a seal on the air inlet of the flame-retardant container 303 under the elastic force of the elastic element 5. At this time, the pressure sensor 8 detects the increase in gas pressure inside the exhaust pipe 301 and sends a signal to the corresponding electric controller to issue an alarm, thereby further assisting in improving the operational safety of the pre-emission of pyrolysis tail gas.

[0037] The battery pyrolysis equipment also includes an explosion-proof component 2, which includes a pressure relief pipe 201 connected to the upper end of the collection container 104. The vent end of the pressure relief pipe 201 is connected to a corresponding water-containing cavity 202. The water-containing cavity 202 is filled with a water-sealing liquid 203 at a level higher than the vent end of the pressure relief pipe 201. A corresponding liquid distribution groove 204 is fitted around the periphery of the water-containing cavity 202. The water-containing cavity 202 is provided with several guide holes facing the bottom side of the liquid distribution groove 204. Each of the guide holes is sealed with an isolation ceramic plate 205, and the liquid distribution tank 204 is filled with a corresponding spare water seal liquid 206. In step S1, when an explosion occurs in the pyrolysis furnace body 102 due to excessive accumulation of electrolyte solvent volatiles, the explosion shock wave is discharged along the pressure relief pipe 201, and the explosion shock wave shatters the isolation ceramic plate 205 to keep the guide hole in a connected state, so that the spare water seal liquid 206 can be introduced into the water containing cavity 202 in time after the explosion to re-seal the pressure relief pipe 201.

[0038] Because the electrolyte solvent volatiles produced by pyrolysis are flammable and explosive, if an explosion occurs due to excessive accumulation of electrolyte solvent volatiles, the explosion shock wave can be discharged along the pressure relief pipe 201 to reduce the explosion loss. When the shock wave generated by the explosion impacts the water seal liquid 203, it is effectively dissipated, and the shock wave will shatter the isolation ceramic plate 205, thereby keeping the guide hole in a connected state so that the spare water seal liquid 206 can be introduced into the water container cavity 202 in time after the explosion, so as to prevent the continuous large-scale discharge of pyrolysis tail gas after the explosion, which would aggravate the severity of the safety accident.

[0039] An oil trap 9 is installed on the exhaust pipe 301. The exhaust pipe 301 includes a horizontal exhaust section 3011, and both ends of the horizontal exhaust section 3011 are connected to the exhaust port of the feed channel 103 and the air inlet of the physical filter device 302 respectively through corresponding conduits 3012. The oil trap 9 includes an oil trapping spiral plate 901 rotatably disposed on the horizontal exhaust section 3011 of the exhaust pipe 301. The oil trapping spiral plate 901 is driven to the output shaft of a corresponding oil trapping drive motor 903 through a corresponding drive shaft 902. In step S2, the oil trapping drive motor 903 drives the oil trapping spiral plate 901 to rotate to trap oil particles in the exhaust gas flowing through the exhaust pipe 301 and transfer the trapped oil back into the feed channel 103 for further pyrolysis. This effectively reduces the amount of small particulate dust and grease entrained in the front exhaust, further enhancing the safety of the front exhaust system.

[0040] The pyrolysis furnace body 102 is provided with a plurality of inclined tipping plates 10 evenly distributed inside, which are used to push the material from the feed end to the discharge end. The pyrolysis furnace body 102 is driven by a corresponding furnace body drive mechanism.

[0041] The furnace body drive mechanism includes an outer gear ring 1101 rotatably disposed at the end of the pyrolysis furnace body 102, and a drive gear 1102 meshing with the outer gear ring 1101. The drive gear 1102 is transmitted to the output shaft end of the corresponding furnace body drive motor 1104 through a corresponding connecting shaft 1103.

[0042] The casing 101 is equipped with a heater 12 for heating the pyrolysis furnace body 102, and the heater 12 is an electric heater.

[0043] The physical filtration device 302 adopts a bag filter dust collector. Since the bag filter dust collector is an existing device, its specific structure will not be described in detail here.

[0044] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A pyrolysis method for battery recycling, characterized in that, The battery pyrolysis device includes the following components: The pyrolysis kiln (1) includes a casing (101) and a pyrolysis furnace body (102) rotatably installed inside the casing (101). A feed channel (103) extending to the feed end of the pyrolysis furnace body (102) is installed on one side of the casing (101). The feed channel (103) is provided with feed inlets and exhaust outlets at intervals. A collection container (104) connected to the discharge end of the pyrolysis furnace body (102) is installed on the other side of the casing (101). A corresponding discharge outlet is provided at the lower end of the collection container (104). The front exhaust assembly (3) includes an exhaust pipe (301) connected to the exhaust port of the feed channel (103), the exhaust pipe (301) being connected to the inlet end of the corresponding physical filter (302), the outlet end of the physical filter (302) being connected to the inlet end of the corresponding flame-retardant container (303), and the outlet end of the flame-retardant container (303) being connected to the inlet end of the corresponding pyrolysis gas combustion furnace (4); a corresponding closing plate (6) is provided on the outside of the inlet end of the flame-retardant container (303) by a corresponding elastic element (5), and the side of the closing plate (6) not connected to the elastic element (5) is fixed by a fusible tensioning assembly (7) so that the elastic element (5) is in a tensioned state, and the tensioning assembly (7) is fixedly connected to the outlet end of the flame-retardant container (303); The battery recycling pyrolysis method includes the following specific steps: S1, the crushed battery fragments are transported by the external feeding mechanism and enter the pyrolysis furnace body (102) through the feeding channel (103). The material is conveyed from the feeding end of the pyrolysis furnace body (102) to the discharge end for high-temperature oxygen-free pyrolysis, and then collected and discharged through the pyrolysis furnace body (102). S2, the exhaust gas generated by high-temperature pyrolysis enters the physical filter device (302) through the exhaust pipe (301) of the front exhaust assembly (3) for particulate matter filtration; S3, the exhaust gas filtered by the physical filtration device (302) is discharged into the pyrolysis gas combustion furnace (4) after passing through the flame-retardant container (303) for combustion. When the combustion flame of the pyrolysis gas combustion furnace (4) extends in the opposite direction into the interior of the flame-retardant container (303), the pulling component (7) is burned off, and the closing plate (6) forms a seal on the air inlet of the flame-retardant container (303) under the elastic force of the elastic element (5).

2. The pyrolysis method for battery recycling according to claim 1, characterized in that, The pulling assembly (7) includes a plurality of pulling ropes (701) arranged in a ring array. One end of each pulling rope (701) is fixed to the back of the closing plate (6), and the other end of each pulling rope (701) is fixed to the gas outlet of the flame-retardant container (303). The middle part of each pulling rope (701) is installed through a fixing hole on the outside of the corresponding ring plate (702).

3. The pyrolysis method for battery recycling according to claim 2, characterized in that, The pulling rope (701) is made of one of nylon rope, polyester rope, or polypropylene rope, and the annular plate (702) is fixed to the flame-retardant container (303) by a corresponding connecting rod.

4. The pyrolysis method for battery recycling according to claim 3, characterized in that, A pressure sensor (8) is installed on the exhaust pipe (301). In step S3, when the combustion flame of the pyrolysis gas combustion furnace (4) extends in the opposite direction into the flame-retardant container (303), the pulling rope (701) of the pulling assembly (7) is burned off, and the closing plate (6) forms a seal on the air inlet of the flame-retardant container (303) under the elastic force of the elastic element (5). At this time, the pressure sensor (8) detects the increase in air pressure in the exhaust pipe (301) and sends a signal to the corresponding electric controller to issue an alarm.

5. The pyrolysis method for battery recycling according to claim 1, characterized in that, The battery pyrolysis equipment also includes an explosion-proof component (2), which includes a pressure relief pipe (201) connected to the upper end of the collection container (104). The exhaust end of the pressure relief pipe (201) is connected to a corresponding water-containing cavity (202). The water-containing cavity (202) is filled with a water-sealing liquid (203) with a liquid level higher than the exhaust end of the pressure relief pipe (201). A corresponding liquid distribution trough (204) is fitted around the periphery of the water-containing cavity (202). Several liquid distribution troughs (204) are provided on the water-containing cavity (202) facing the bottom of the liquid distribution trough (204). The guide hole on the side is sealed with an isolation ceramic plate (205), and the liquid distribution tank (204) is filled with a corresponding spare water seal liquid (206). In step S1, when an explosion occurs in the pyrolysis furnace body (102) due to excessive accumulation of electrolyte solvent volatiles, the explosion shock wave is discharged along the pressure relief pipe (201), and the explosion shock wave shatters the isolation ceramic plate (205) to make the guide hole in a connected state, so that the spare water seal liquid (206) can be introduced into the water container cavity (202) in time after the explosion to re-seal the pressure relief pipe (201).

6. The pyrolysis method for battery recycling according to claim 1, characterized in that, An oil trap (9) is provided on the exhaust pipe (301). The exhaust pipe (301) includes a horizontal exhaust section (3011). The two ends of the horizontal exhaust section (3011) are respectively connected to the exhaust port of the feed channel (103) and the air inlet of the physical filter device (302) through corresponding conduits (3012). The oil trap (9) includes an oil trapping spiral that is rotatably disposed on the horizontal exhaust section (3011) of the exhaust pipe (301). The oil-collecting spiral plate (901) is connected to the output shaft of the corresponding oil-collecting drive motor (903) via a corresponding drive shaft (902); in step S2, the oil-collecting drive motor (903) drives the oil-collecting spiral plate (901) to rotate so as to collect oil particles in the exhaust gas flowing through the exhaust pipe (301) and transfer the collected oil back to the feed channel (103) for pyrolysis again.

7. The pyrolysis method for battery recycling according to claim 1, characterized in that, The pyrolysis furnace body (102) is provided with a plurality of inclined tipping plates (10) for pushing materials from the feed end to the discharge end. The pyrolysis furnace body (102) is driven by a corresponding furnace body drive mechanism.

8. The pyrolysis method for battery recycling according to claim 7, characterized in that, The furnace body drive mechanism includes an outer gear ring (1101) rotatably disposed at the end of the pyrolysis furnace body (102) and a drive gear (1102) meshing with the outer gear ring (1101). The drive gear (1102) is driven to the output shaft end of the corresponding furnace body drive motor (1104) through a corresponding connecting shaft (1103).

9. The pyrolysis method for battery recycling according to claim 1, characterized in that, The casing (101) is equipped with a heater (12) for heating the pyrolysis furnace body (102), and the heater (12) is an electric heater.

10. The pyrolysis method for battery recycling according to claim 1, characterized in that, The physical filtration device (302) adopts a bag filter dust collector.

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