A fully automatic processing farmland waste plastic film regeneration production system

Abstract

The application relates to the technical field of waste land film regeneration, and particularly discloses a full-automatic farmland waste land film regeneration production system, which comprises a crushing mechanism, a cleaning mechanism, a sorting mechanism and a granulating mechanism, the cleaning mechanism is arranged on one side of the crushing mechanism, the sorting mechanism is arranged on the side, away from the crushing mechanism, of the cleaning mechanism, and the granulating mechanism is arranged on one side of the sorting mechanism; the sorting mechanism comprises a sorting pool and a detection assembly, a control module is arranged on one side of the sorting pool, a partition plate and a liquid discharge pipe are arranged in the sorting pool, a spray head is arranged on the liquid discharge pipe, a containing groove is formed through the partition plate, the spray head is movably connected with the containing groove, the spray head can inject a sorting liquid into the sorting pool, and waste land films with different aging degrees can be naturally layered in the sorting liquid; the detection assembly is arranged on the inner wall of the sorting pool, and the detection assembly can detect the positions of different aging waste land films in the sorting pool. The application has the effects of improving the quality and recovery efficiency of regenerated granules.

Description

Technical Field

[0001] This application relates to the field of waste plastic film recycling technology, and in particular to a fully automated system for processing and recycling farmland waste plastic film. Background Technology

[0002] Agricultural mulch film, widely used in modern agricultural production, serves multiple functions, including heat preservation, moisture retention, insect prevention, increasing soil temperature, and promoting early maturity and yield increases in crops. Its application is particularly prevalent in field crop cultivation. After the crop growth cycle, mulch film becomes agricultural waste. If not recycled and disposed of in a timely manner, it not only wastes resources but also causes long-term pollution to the soil environment and ecosystem, becoming one of the main sources of "white pollution." Therefore, the state and relevant agricultural production departments attach great importance to the recycling and reuse of waste mulch film and are continuously promoting the development of fully automated, large-scale mulch film recycling and processing systems.

[0003] Currently, most waste plastic film recycling and processing systems on the market mainly use mechanical crushing, washing, and melt extrusion processes. Existing farmland waste plastic film recycling and processing systems mainly include mechanized recycling devices, crushing and washing equipment, and melt granulation equipment, realizing the overall process from waste film recycling to recycled granules. These systems usually use specialized recycling equipment to collect waste plastic film in the field, collecting the waste plastic film along with the mixed soil and plant residues. Subsequently, impurities are removed through high-pressure water washing, centrifugal dehydration, and hot air drying, and then high-temperature melt extrusion granulation is performed. For example, Chinese patent CN201610676955.8, in the relevant technology, proposes a fully automatic pure physical and mechanical processing production line for the recycling of farmland waste plastic film, which includes: a twin-screw extruder for crushing impurities in the recycled film material; a crushing system for cutting and crushing the recycled film material mixed with crushed impurities to obtain fragmented impurities and sheet-like film; a high-speed centrifugal separation device for separating the fragmented impurities; a residual impurity separation system for mechanically rubbing the film after the fragmented impurities have been separated; and a high-speed centrifugal impurity separation system for centrifugally rubbing the film after mechanical friction.

[0004] However, in practical applications, the sources of recycled waste plastic film are complex. They include film material that has been exposed to the surface for a long time, severely aged and broken by ultraviolet radiation and natural wind and rain, as well as film material buried in the soil that is relatively less aged and has less residual pollution. Severely aged, broken, and mixed with impurities, waste plastic film is prone to causing equipment wear and blockage during processing, and it is difficult to obtain high-quality recycled materials. On the other hand, less polluted and more intact waste plastic film has higher recycling value. Current technologies, however, indiscriminately mix the two types of waste film after recycling, failing to effectively classify them according to their aging degree and pollution level, resulting in increased processing burden and reduced recycling efficiency. Summary of the Invention

[0005] This application provides a fully automated system for processing and recycling waste agricultural film. This system can classify and recycle waste agricultural film of different aging levels based on density differences, thereby improving the overall operating efficiency and stability of the agricultural film recycling system and promoting the efficient recycling and high-quality regeneration of waste agricultural film.

[0006] The fully automated system for processing and recycling waste agricultural film provided in this application adopts the following technical solution:

[0007] A fully automated system for processing and recycling agricultural waste plastic film includes:

[0008] The system includes a crushing mechanism for uniformly crushing waste plastic film, a cleaning mechanism for cleaning the crushed waste plastic film, a sorting mechanism for sorting waste plastic film of different aging degrees, and a granulation mechanism for granulating waste plastic film slag. The cleaning mechanism is located on one side of the crushing mechanism, the sorting mechanism is located on the side of the cleaning mechanism away from the crushing mechanism, and the granulation mechanism is located on one side of the sorting mechanism.

[0009] The sorting mechanism includes a sorting pool and a detection component. A control module is provided on one side of the sorting pool. A drain pipe is provided inside the sorting pool. A partition plate is provided inside the sorting pool. The partition plate is located above the drain pipe. A nozzle is provided on the drain pipe. A receiving groove is provided through the partition plate. The nozzle is movably connected to the receiving groove. The nozzle can inject sorting liquid into the sorting pool at a certain critical flow rate. Waste plastic film with different aging degrees will naturally separate into layers in the sorting liquid.

[0010] The detection component is installed on the inner wall of the sorting tank, and the detection component is able to detect the position of different aged waste plastic film in the sorting tank.

[0011] By adopting the above technical solution, a crushing mechanism, a washing mechanism, a sorting mechanism, and a granulation mechanism are sequentially set in the production system, constructing a farmland waste plastic film recycling system with continuous process, integrated functions, and a high degree of automation. The sorting mechanism introduces a differentiated treatment mechanism based on the natural stratification principle of the sorting liquid. By setting up partition plates, nozzles, and drain pipes in the sorting tank, when the sorting liquid flows upward through the plastic film fragments at a certain critical velocity, the drag force generated by the fluid on the plastic film fragments gradually offsets the weight of the plastic film fragments, thereby promoting the natural stratification of waste film of different densities within the sorting tank. The initial screening process requires no manual intervention. Simultaneously, a detection component monitors the sorting status in real time, identifying the floating / settling positions of various waste films. This provides a basis for subsequent control modules to schedule material discharge or diversion, ensuring an intelligent, efficient, and precise sorting process. The overall solution, by classifying and processing waste agricultural film of different properties, not only reduces the risk of damage and clogging to system equipment from highly polluting films but also improves the homogeneity and stability of raw materials in the subsequent granulation stage. This significantly enhances the quality and recycling efficiency of recycled granules, driving the development of agricultural film recycling towards intelligent sorting, clean recycling, and automated closed-loop systems.

[0012] Optionally, the sorting mechanism includes a magnetic separation component, which includes a lifting drive, a frequency converter, and a coil. The sorting liquid in the sorting tank is a suspension prepared by mixing deionized water and MnFe2O4. The lifting drive and the frequency converter are both disposed on the outer wall of the sorting tank. The lifting drive is electrically connected to the control module. The frequency converter can output high-frequency alternating current and direct current. The frequency converter is electrically connected to the control module. The coil is electrically connected to the frequency converter. The coil is slidably disposed on the outer wall of the sorting tank. The output end of the lifting drive is fixedly connected to the coil. The lifting drive can drive the coil to slide back and forth on the outer wall of the sorting tank in a vertical direction.

[0013] By adopting the above technical solution, a magnetic suspension made of deionized water and MnFe2O4 is introduced into the sorting mechanism. The technical purpose is to create a fluidized environment through this liquid medium and utilize the differences in density, adsorption characteristics and magnetic response exhibited by different waste plastic film due to differences in aging degree to achieve higher precision automatic sorting. Among them, deionized water provides a stable and uniform suspended fluid environment, which allows film materials of different densities to stratify in the pool.

[0014] The introduction of MnFe2O4 particles is based on the following two key mechanisms: Firstly, waste plastic film exposed to the ground for a long time has a rougher surface structure and a large number of microcracks and pores due to environmental factors such as ultraviolet radiation, oxidation, and mechanical friction. It is also easy for impurities such as plant residues to adhere to it, thus providing a large number of adsorption sites for MnFe2O4 nanoparticles. In contrast, waste film buried underground has a dense structure, fewer surface defects, and a weaker ability to adsorb nanoparticles. Therefore, in magnetic suspensions, severely aged film material will adsorb more magnetic particles, significantly enhancing its responsiveness to changes in magnetic field. On the other hand, the sorting system is equipped with a frequency converter and a sliding coil device. The control module drives the frequency converter to output a high-frequency alternating current to the coil, forming an alternating magnetic field in the sorting pool. MnFe2O4 particles undergo superparamagnetic rotation and magnetic moment reversal behavior in the magnetic field, which induces hysteresis loss and efficiently releases heat energy. The local temperature rises rapidly, causing the liquid around the particles to vaporize rapidly and generate micron-sized bubbles. Under the continuous action of the magnetic field, these bubbles undergo rapid expansion-compression-implosion, generating strong cavitation shock waves and high-speed microjets, thereby accurately peeling off and cleaning the adhering substances (such as plant residues) on the surface of the aged film.

[0015] In summary, by constructing an intelligent identification and precise sorting system through the dual means of physical density difference and magnetic response difference, the accuracy of aging membrane identification can be improved. Furthermore, the magnetic response difference can be used to assist in the stratification of the membrane in the sorting solution, and the membrane surface can be purified simultaneously during the sorting process. This solves the problems of inaccurate sorting and severe stratification interference in the existing technology, significantly improves sorting efficiency and subsequent regeneration quality, reduces energy consumption, and reduces manual intervention.

[0016] Optionally, the detection component includes a light curtain and a photosensitive plate. The light curtain and the photosensitive plate are respectively fixedly embedded on the inner wall of the long side of the sorting pool, and the light curtain and the photosensitive plate are symmetrically arranged along the width direction of the sorting pool. The light-emitting surface of the light curtain is flush with the inner wall of the sorting pool. Several sets of photosensitive sensors are integrated on the photosensitive plate. The photosensitive plate is electrically connected to the control module, and the photosensitive surface on the photosensitive plate is flush with the inner wall of the sorting pool.

[0017] By adopting the above technical solution, the detection component is a non-contact photoelectric detection structure composed of a light curtain and a photosensitive plate. By arranging through-beam light paths on both sides of the sorting tank, it can realize real-time detection of the vertical distribution of waste plastic film at different heights within the sorting tank. The light beam emitted by the light curtain is blocked when plastic film fragments pass through. The degree of light blocking varies at different locations, and the signal strength and layer identification can be judged by multiple photosensitive sensor arrays set on the photosensitive plate. This structure has high detection accuracy and fast response speed, and can dynamically collect the actual floating and sinking state of waste plastic film in the sorting liquid, providing accurate position data for the control module. This assists the system in judging the degree of aging of waste plastic film and subsequent discharge path. Compared with the traditional sorting method that relies on manual observation or simple floating and sinking judgment, the photoelectric detection structure provided by this technical solution significantly improves the degree of automation and intelligent decision-making ability, reduces the human error rate, and helps to achieve the purpose of graded treatment and differentiated recycling of waste plastic film, further optimizing the resource allocation efficiency of the entire processing chain.

[0018] Optionally, the sorting mechanism further includes a mixing component, which includes a support beam, a displacement drive, a first motor, a stirring rod, a rack, and a gear. The support beam is mounted on the open end of the sorting tank, and the displacement drive is located on one side of the open end of the sorting tank. A rotating shaft is fixed to one end of the support beam, and a first connecting block is rotatably mounted on the rotating shaft. The first connecting block is slidably mounted on the open end of the sorting tank. The output end of the displacement drive is connected to the first connecting block. A second connecting block is rotatably mounted on the other end of the support beam, and the second connecting block is slidably mounted on the open end of the sorting tank. The first connecting block and the second connecting block are symmetrically arranged along the width direction of the sorting pool. The first motor is fixed on the support beam and electrically connected to the control module. One end of the stirring rod is provided with a stirring part, and the other end of the stirring rod is connected to the output end of the first motor. The gear is fixed on the rotating shaft, and the rack is fixed on the opening end of the sorting pool. The gear meshes with the rack. When the displacement driving member drives the support beam to slide along the length direction of the sorting pool, the support beam deflects to one side under the action of the gear, thereby causing the stirring rod to extend into the sorting pool for stirring.

[0019] By adopting the above technical solution, the mixing component, through the coordinated operation of the support beam, stirring rod, and displacement drive mechanism, achieves directional stirring inside the sorting liquid, resulting in two significant technical effects: Firstly, addressing the problem that waste plastic film fragments have low density and light volume, often floating on the surface of the sorting liquid and struggling to participate in effective stratification, the mixing component can press the floating lightweight film fragments into the sorting liquid after feeding, ensuring they are fully submerged and interact with the sorting medium, thereby improving sorting accuracy. Secondly, the powerful stirring allows the MnFe2O4 magnetic particles in the sorting liquid to fully contact and encapsulate the waste plastic film with varying degrees of aging, especially causing the surface of the more aged film to adsorb more magnetic particles, providing a good pretreatment foundation for the subsequent magnetic sorting process and significantly improving magnetic response differences and sorting efficiency. In addition, the gear-rack linkage structure in the component allows for synchronous deflection and insertion of the stirring rod during the drive displacement process, avoiding mechanical interference, ensuring stable and efficient stirring, and further improving the overall automation level and operational continuity of the system.

[0020] Optionally, the mixing assembly further includes a pressure screen and an elastic element. The pressure screen is configured as a rectangular plate. A feeding port is provided on the sorting tank. The pressure screen is lifted and slidably disposed in the sorting tank. The pressure screen is disposed between the support beam and the partition plate. The pressure screen is located above the feeding port. An avoidance groove is provided through the pressure screen. A shielding curtain is provided in the avoidance groove. An abutment part is fixed on one side of the pressure screen near the support beam. An abutment seat is rotatably disposed on the stirring rod. The elastic element is disposed on the pressure screen. One end of the elastic element is fixedly connected to the pressure screen, and the other end of the elastic element is fixedly connected to the inner wall of the sorting tank. When the stirring rod extends into the sorting tank for stirring, the abutment seat squeezes the abutment part, thereby causing the pressure screen to press the waste film floating on the surface into the sorting liquid.

[0021] By adopting the above technical solution, and by setting a pressure net that can rise and fall in tandem with the stirring rod in the sorting tank, supplemented by a shielding curtain and an elastic limiting structure, the waste mulch film can be effectively pressed down on the surface of the sorting liquid after it is fed in. This allows the film fragments to fully immerse in the sorting liquid and participate in natural stratification. Compared with the problem of light film floating and difficulty in stratification in the prior art, this device achieves passive film pressing into the liquid without adding independent power components by linking the rotation and displacement of the stirring rod with the lifting and lowering of the pressure net. This avoids sorting errors caused by film floating and improves the accuracy of identifying mulch film of different aging grades and the intelligent decision-making ability of subsequent sorting paths. At the same time, the setting of the avoidance trough and the shielding curtain effectively prevents the floating waste mulch film fragments from being carried out of the sorting tank by the stirring rod during the stirring process, reducing the overflow and loss of film material. This solves the technical problems of light film floating and film overflow during stirring, and improves the accuracy of waste mulch film sorting and the reliability of system operation.

[0022] Optionally, a connecting groove is provided on the end face of the stirring rod away from the stirring part. A transmission block is fixed on the output end of the first motor. The transmission block is movably inserted into the connecting groove. A limiting block is fixed on the end of the stirring rod with the connecting groove. The limiting block is an arc-shaped block, and both ends of the limiting block along the axis of the stirring rod are set as inclined surfaces. Two sets of limiting blocks are arranged on the circumference of the stirring rod, and a limiting groove is formed between the two sets of limiting blocks. The limiting groove is directly opposite the stirring part. A limiting sleeve is provided on the support beam. The limiting sleeve is coaxially sleeved on the stirring rod. The limiting block and the limiting sleeve are slidably connected. One end of the limiting sleeve is fixedly connected to the support beam. An anti-detachment ring is fixed on the other end of the limiting sleeve. Two sets of limiting rods are arranged on the circumference of the inner wall of the end of the limiting sleeve with the anti-detachment ring, and the limiting rods are slidably connected to the limiting groove.

[0023] By adopting the above technical solution, and utilizing the combination of the limiting block and the limiting sleeve, the posture and movement trajectory of the stirring rod when it extends into and out of the sorting tank can be strictly limited, ensuring that the stirring rod's posture is consistent and stable during each operation. Since the purpose of the screen pressing is to fully immerse the mulch film fragments in the sorting liquid, the extent to which the clearance trough is opened is limited. The combination of the limiting block and the limiting sleeve effectively prevents the floating waste mulch film fragments from being carried out of the sorting tank by the stirring rod during the stirring process, reducing film spillage and loss, and improving the waste film recovery rate. At the same time, it avoids interference between the stirring rod and the screen pressing clearance trough due to unstable posture, ensuring the safe and reliable operation of the equipment and improving the overall processing efficiency and economic benefits of the system.

[0024] Optionally, the sorting mechanism further includes a discharge assembly, which includes a blocking drive, a blocking plate, a discharge hopper, a baffle, and a third motor. A discharge port is provided on the wide side of the sorting pool, and a clearance groove is provided on the inner wall of the discharge port. One end of the blocking plate is slidably disposed within the clearance groove. The blocking drive is disposed on the opening end of the sorting pool and is electrically connected to the control module. The output end of the blocking drive is fixedly connected to the blocking plate. The discharge hopper is fixedly disposed on the outer wall of the sorting pool, located below the discharge port, and facing away from the sorting pool. Two sets of feed pipes are fixedly provided at one end of the discharge hopper. The two sets of feed pipes are symmetrically arranged along the width direction of the discharge hopper. The baffle is rotatably disposed at the end of the discharge hopper away from the sorting tank. One end of the baffle rotatably abuts against the inner wall of the discharge hopper. The baffle is located between the two sets of feed pipes and can selectively block one of the two sets of feed pipes. The third motor is fixed on the discharge hopper and is electrically connected to the control module. The output end of the third motor is connected to the end of the baffle that abuts against the inner wall of the discharge hopper. The third motor can drive the baffle to rotate inside the discharge hopper.

[0025] By adopting the above technical solution and setting up a discharge assembly consisting of a blocking drive, a blocking plate, a discharge hopper, a baffle, and a motor, the automatic diversion and precise discharge of waste agricultural film with different aging levels in the sorting tank are realized. This structure can automatically control the opening and closing of the blocking plate and the rotation of the baffle according to the detected distribution of waste film, so as to realize the batch discharge of waste film according to sorting grade, avoid the mixing of waste film of different grades, and significantly improve the targeting and efficiency of the recycling process. Specifically, the blocking drive and the blocking plate work together to quickly and accurately block or open the discharge port, ensuring the smoothness and stability of the discharge process of agricultural film fragments floating on the liquid surface. The coordinated action of the discharge hopper and the baffle realizes the flexible blocking and opening of the distribution pipe, so that the waste film can be guided to different recycling channels, preventing cross-contamination of recycled materials, improving the overall operating efficiency and stability of the system, and promoting the efficient recycling and high-quality regeneration of waste agricultural film.

[0026] Optionally, the sorting mechanism further includes a discharge assembly, which includes a screening screen and a lifting drive. The screening screen is disposed on the side of the partition plate opposite to the drain pipe. A scraper is fixedly disposed on one side of the screening screen, and the scraper slides against the inner wall of the sorting tank where the light curtain is embedded. Two sets of scrapers are provided, and the two sets of scrapers are symmetrically arranged along the width direction of the sorting tank. The lifting drive is fixedly disposed on the outer wall of the sorting tank, and the output end of the lifting drive is fixedly connected to the screening screen. The lifting drive can drive the screening screen to reciprocate vertically within the sorting tank.

[0027] By adopting the above technical solution, the discharge assembly is mainly used to extract the lightly aged waste plastic film that has settled to the bottom of the sorting liquid. During the sorting process, the lightly aged waste plastic film sinks to the bottom of the sorting tank due to its higher density, while the severely aged waste plastic film floats to the upper or middle layer. After the system removes the severely aged waste plastic film, the discharge assembly further processes the sediment through a screening screen. The screening screen can effectively distinguish between the waste plastic film and plant residues deposited at the bottom of the sorting tank, separating the attached plant residues from the plastic film and preventing the plant residues from entering the subsequent melting and granulation stage with the waste film, thus avoiding contamination of the quality of the recycled material. This discharge assembly achieves effective separation and automatic conveying of waste plastic film and plant residues, improving the purity of the recycled plastic film and the automation level of the system, and reducing the difficulty of subsequent processing and equipment maintenance costs. In addition, the reciprocating motion of the scraper in conjunction with the lifting drive can continuously clean the surface of the photosensitive plate and the light curtain, preventing impurities from adhering to the surface and affecting the detection accuracy.

[0028] In summary, this application includes at least one of the following beneficial technical effects:

[0029] 1. A production system is constructed by sequentially setting up a crushing mechanism, a washing mechanism, a sorting mechanism, and a granulation mechanism, thus creating a continuous process, integrated functions, and a high degree of automation in the recycling of agricultural waste plastic film. The sorting mechanism incorporates a differentiated treatment mechanism based on the natural stratification principle of the sorting liquid, promoting the natural stratification of waste films of different densities within the sorting tank, achieving preliminary screening without manual intervention. Simultaneously, a detection component monitors the sorting status in real time, identifying the floating / settling positions of various types of waste films, providing a basis for subsequent control modules to schedule discharge or diversion, ensuring the sorting process is intelligent, efficient, and precise. By classifying and treating waste plastic film of different properties, the overall solution not only reduces the risk of damage and clogging to system equipment from highly polluting films but also improves the homogeneity and stability of raw materials in the subsequent granulation stage, thereby significantly improving the quality and recycling efficiency of the recycled granules and promoting the development of agricultural plastic film recycling towards intelligent sorting, clean recycling, and automated closed-loop systems.

[0030] 2. A magnetic suspension composed of deionized water and MnFe2O4 is introduced into the sorting mechanism. This liquid medium creates a fluidized environment, utilizing the differences in density, adsorption characteristics, and magnetic response exhibited by different waste mulch films due to varying degrees of aging to achieve higher precision automatic sorting. Deionized water provides a stable and uniform suspended fluid environment, allowing membrane materials of different densities to stratify in the pool. The introduction of MnFe2O4 particles significantly enhances the responsiveness of severely aged mulch films to changes in the magnetic field. Furthermore, the special properties of MnFe2O4 particles in a magnetic field allow for precise peeling and cleaning of plant residues from the surface of the aged membrane. In summary, by constructing an intelligent identification and precise sorting system through a dual approach of physical density difference and magnetic response difference, the accuracy of aged membrane identification is improved. The magnetic response difference also assists in stratification in the sorting liquid, and membrane surface purification is completed simultaneously during the sorting process. This solves the problems of inaccurate sorting and severe stratification interference in existing technologies, significantly improving sorting efficiency and subsequent regeneration quality, reducing energy consumption, and minimizing manual intervention.

[0031] 3. The mixing component, through the coordinated operation of the support beam, stirring rod, and displacement drive mechanism, achieves directional stirring within the sorting liquid. On one hand, addressing the issue that waste plastic film fragments have low density and light volume, often floating on the surface of the sorting liquid and struggling to participate in effective stratification, the mixing component can press the floating lightweight film fragments into the sorting liquid after feeding, ensuring they are fully submerged and interact with the sorting medium, thereby improving sorting accuracy. On the other hand, the powerful stirring ensures that the MnFe2O4 magnetic particles in the sorting liquid fully contact and coat the waste plastic film with varying degrees of aging, especially allowing the surface of the more aged film to adsorb more magnetic particles, providing a good pretreatment foundation for the subsequent magnetic sorting process and significantly improving magnetic response differences and sorting efficiency. In addition, the linkage structure between the limiting block and the limiting sleeve in the component allows for synchronous deflection and insertion of the stirring rod during the drive displacement process, avoiding mechanical interference and ensuring a stable and efficient stirring process, further enhancing the overall automation level and operational continuity of the system. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the overall structure of the waste plastic film recycling production system in the embodiments of this application.

[0033] Figure 2 This is a partial cross-sectional view of the sorting pool in an embodiment of this application.

[0034] Figure 3 This is a schematic diagram of the overall structure of the sorting mechanism in the embodiments of this application.

[0035] Figure 4 This is a schematic diagram of the overall structure of the stirring rod in an embodiment of this application.

[0036] Figure 5 This is a schematic diagram of the overall structure of the mixing component and the granulation component in the embodiments of this application.

[0037] Reference numerals: 1. Crushing mechanism; 11. Hydraulic slitting machine; 12. Shredder; 13. Crusher; 14. Transfer conveyor belt; 141. First conveyor belt; 142. Second conveyor belt;

[0038] 2. Cleaning mechanism; 21. Friction washing machine; 22. Cleaning tank; 23. Elevator;

[0039] 3. Sorting mechanism; 31. Sorting tank; 311. Drain pipe; 3111. Nozzle; 312. Divider plate; 3121. Receiving tank; 313. Feeding port; 314. Discharge port; 315. Clearing trough; 32. Detection assembly; 321. Light curtain; 322. Photosensitive plate; 33. Magnetic separation assembly; 331. Lifting drive component; 332. Variable frequency power supply; 333. Coil;

[0040] 34. Mixing component; 341. Support beam; 3411. Rotating shaft; 3412. First connecting block; 3413. Second connecting block; 342. Displacement drive component; 343. First motor; 3431. Transmission block; 345. Stirring rod; 3451. Stirring part; 3452. Abutment seat; 3453. Connecting groove; 3454. Limiting block; 3455. Limiting groove; 3456. Limiting sleeve; 3457. Anti-detachment ring; 3458. Limiting rod; 346. Rack; 347. Gear; 348. Pressure net; 3481. Clearance groove; 3482. Shielding curtain; 3483. Abutment part; 349. Elastic component;

[0041] 35. Discharge assembly; 351. Blocking drive component; 352. Blocking plate; 353. Discharge hopper; 354. Baffle; 355. Third motor; 356. Distributor pipe; 36. Discharge assembly; 361. Screening screen; 362. Lifting drive component; 363. Scraper;

[0042] 4. Granulation mechanism; 41. Washing conveyor belt; 42. Granulation extruder;

[0043] 5. Control module. Detailed Implementation

[0044] The following is in conjunction with the appendix Figure 1-5 This application will be described in further detail.

[0045] This application discloses a fully automated system for processing and regenerating waste agricultural film.

[0046] Reference Figure 1 The fully automated agricultural waste film recycling production system includes a crushing mechanism 1, a washing mechanism 2, a sorting mechanism 3, a granulation mechanism 4, and a control module 5. The washing mechanism 2 is installed on the left side of the crushing mechanism 1, the sorting mechanism 3 is installed on the right side of the crushing mechanism 1, the granulation mechanism 4 is installed on the right side of the sorting mechanism 3, and the control module 5 is installed in front of the sorting mechanism 3.

[0047] The crushing mechanism 1 can uniformly crush waste plastic film, while the washing mechanism 2 can wash the crushed waste plastic film fragments in stages to remove larger solid impurities and pesticide residues. The sorting mechanism 3 can sort waste plastic film fragments of different aging degrees, and can also remove plant residues from the sorted waste plastic film fragments with severe aging degrees. The granulation mechanism 4 can granulate the waste plastic film fragments with molten slag. The control module 5 can uniformly control the electrical components in the crushing mechanism 1, washing mechanism 2, sorting mechanism 3 and granulation mechanism 4.

[0048] Reference Figure 1In the implementation of this application, before being crushed by the crushing mechanism 1, all waste plastic film will undergo a uniform pre-cleaning treatment to remove most of the soil gravel and most of the solid impurities mixed on it. The crushing mechanism 1 includes a hydraulic slitter 11, a shredder 12, a crusher 13, and a transfer conveyor belt 14. The transfer conveyor belt 14 is provided in two sets, which are respectively designated as a first conveyor belt 141 and a second conveyor belt 142. A mounting frame is installed at one end of the first conveyor belt 141, and the hydraulic slitter 11 is mounted on the mounting frame. The hydraulic slitter 11 is positioned above the first conveyor belt 141. The hydraulic slitter 11 can compress and cut the pre-cleaned waste plastic film into pieces of similar size. The hydraulic slitter 11 is provided with a first feed inlet and a first discharge outlet. The end of the first conveyor belt 141 near the mounting frame is designated as the first feed end, and the other end of the first conveyor belt 141 is designated as the first discharge end. The first discharge outlet of the hydraulic slitter 11 is connected to the first feed end of the first conveyor belt 141.

[0049] A shredder 12 is installed on the side of the first conveyor belt 141 away from the hydraulic slitter 11. The shredder 12 can initially break up the fragments cut by the hydraulic slitter 11. The shredder 12 is provided with a second feed inlet and a second discharge outlet. The first discharge end of the first conveyor belt 141 is connected to the second feed inlet. A second conveyor belt 142 is installed on the side of the shredder 12 away from the first conveyor belt 141. One end of the second conveyor belt 142 is set as the second feed end, and the other end of the second conveyor belt 142 is set as the second discharge end. The second discharge outlet is connected to the second discharge end.

[0050] The crusher 13 is installed on the side of the second conveyor belt 142 away from the shredder 12. The crusher 13 can further crush the waste film into film fragments of uniform size. The crusher 13 is provided with a third feed port and a third discharge port. The second discharge end on the second conveyor belt 142 is connected to the third feed port.

[0051] Reference Figure 1 In this embodiment, the cleaning mechanism 2 includes a friction washing machine 21, a cleaning tank 22, and a hoist 23. The friction washing machine 21 includes a support, a washing cylinder, a spiral feeding rod, and a second motor. The support is installed on the side of the crusher 13 away from the second conveyor belt 142. The washing cylinder is inclined and fixed on the support. A first feed pipe is fixed at one end of the washing cylinder, and a first discharge pipe is fixed at the other end of the washing cylinder. Both the first feed pipe and the first discharge pipe are connected to the washing cylinder. The first feed pipe is connected to the third discharge port.

[0052] A spray pipe is installed at one end of the washing cylinder near the first feed pipe, and several sets of nozzles are installed on the spray pipe. The nozzles are fixedly embedded in the washing cylinder. Multiple sets of drain holes are opened at the end of the washing cylinder with the first discharge pipe. The drain holes and the first discharge pipe are both located on the side of the washing cylinder facing the support, and the multiple sets of drain holes are arranged in an array at equal intervals on the washing cylinder.

[0053] The spiral feed tube is coaxially rotated inside the washing cylinder. The second motor is fixed at the end of the washing cylinder where the first discharge tube is located. The second motor can be a servo motor, and the output end of the second motor is fixedly connected to one end of the spiral feed rod.

[0054] In this embodiment, three sets of friction washing machines 21 are arranged in sequence. After the mulch film fragments crushed by the crusher 13 pass through the three sets of friction washing machines 21, most of the soil gravel and plant residues can be effectively removed.

[0055] The cleaning tank 22 includes a tank body and a material-removing roller. The material-removing roller is cylindrical and has multiple sets of material-removing rods fixed on it. The multiple sets of material-removing rods are arranged in a circumferentially spaced manner on the material-removing roller. The material-removing roller is mounted on the tank body and has multiple sets of material-removing rollers. The multiple sets of material-removing rollers are arranged at equal intervals along the length of the tank body.

[0056] In this embodiment, three sets of cleaning water tanks 22 are arranged in sequence, and three sets of elevators 23 are also provided. Each set of elevators 23 is located at the end of each set of cleaning water tanks 22 away from the friction washing machine 21. The elevators can be used to transfer the plastic film fragments.

[0057] More specifically, the pre-cleaned waste plastic film is fed into a hydraulic slitting machine 11, which cuts it into plastic film fragments of similar size. The plastic film fragments are then crushed into uniformly sized plastic film pieces by a tearing machine 12 and a crusher 13. After being cleaned by three sets of friction washing machines 21, the cleaned plastic film pieces are fed into a cleaning tank 22. In the cleaning tank 22, since the plastic film pieces float on the water surface, most of the solid impurities and plant residues are separated.

[0058] Reference Figure 2 and Figure 3In this embodiment, the sorting mechanism 3 includes a sorting pool 31, a detection component 32, a discharge component 36, a magnetic separation component 33, a mixing component 34, and a discharge component 35. The sorting pool 31 is located on one side of a set of lifting members away from the crusher 13, and is located on the side of the set of lifting members 23 away from the crusher 13. A feeding port 313 is provided on the side wall of the sorting pool 31. The feeding port 313 is connected to the output end of the set of lifting members 23 near the sorting pool 31. An electrically controlled valve is also installed on the feeding port 313. The electrically controlled valve is electrically connected to the control module 5. A drain pipe 311 is provided on the bottom wall of the sorting tank 31. Several sets of nozzles 3111 are fixed on the drain pipe 311. A partition plate 312 is fixed above the drain pipe 311. The size of the partition plate 312 is the same as the size of the bottom wall of the sorting tank 31. The output end of the nozzle 3111 points vertically to the partition plate 312. One end of the drain pipe 311 extends through the side wall of the sorting tank 31 to the outside of the sorting tank 31. The drain pipe 311 and the sorting tank 31 are sealed together. There are multiple sets of drain pipes 311. The multiple sets of drain pipes 311 are arranged at equal intervals along the length of the sorting tank 31. A receiving groove 3121 is opened through the partition plate 312. The nozzles 3111 and the receiving groove 3121 are movably inserted and matched.

[0059] Waste liquid tank and storage tank are respectively provided on the outside of the sorting tank 31. The storage tank is filled with sorting liquid. A liquid injection pump is installed on the storage tank. The liquid injection pump is electrically connected to the control module 5. The liquid injection pump is provided with an input end and an output end. A first liquid delivery pipe is installed on the input end of the liquid injection pump. The liquid injection pump is connected to the storage tank through the first liquid delivery pipe. A second liquid delivery pipe is installed on the output end of the liquid injection pump. The second liquid delivery pipe is connected to one end of each set of drain pipes 311 that extends to the outside of the sorting tank 31.

[0060] In this embodiment, the sorting liquid is a suspension prepared by mixing deionized water and MnFe2O4, and the waste liquid tank is not shown in the accompanying drawings of this embodiment.

[0061] The detection component 32 includes a light curtain 321 and a photosensitive plate 322. Both the light curtain 321 and the photosensitive plate 322 are fixedly embedded in the inner wall of the sorting pool 31, and the light curtain 321 and the photosensitive plate 322 are symmetrically arranged along the width direction of the sorting pool 31. The light-emitting surface of the light curtain 321 is flush with the inner wall of the sorting pool 31. Several sets of photosensitive sensors are integrated on the photosensitive plate 322. The photosensitive plate 322 is electrically connected to the control module 5, and the photosensitive surface on the photosensitive plate 322 is also flush with the inner wall of the sorting pool 31.

[0062] The discharge assembly 36 includes a screening screen plate 361 and a lifting drive component 362. The screening screen plate 361 is disposed on the side of the partition plate 312 facing away from the drain pipe 311. The two sides of the screening screen plate 361 in the length direction abut against the inner wall of the separation tank 31. Scrapers 363 are fixedly provided on both sides of the screening screen plate 361 in the width direction. The scrapers 363 abut against the inner wall of the separation tank 31, where the light curtain 321 and the photosensitive plate 322 are embedded. The lifting drive component 362 is fixedly disposed on the outer bottom wall of the separation tank 31. The lifting drive component 362 can be configured as an electric telescopic cylinder. The output end of the lifting drive component 362 is fixedly connected to the screening screen plate 361, and the output end of the lifting drive component 362 is slidably sealed to the bottom wall of the separation tank 31.

[0063] The magnetic separation component 33 includes a lifting drive 331, a frequency converter 332, and a coil 333. The lifting drive 331 is installed on the outer wall of the sorting pool 31. In this embodiment, the lifting drive 331 can be configured as an electric telescopic cylinder. The lifting drive 331 is electrically connected to the control module 5. The frequency converter 332 is fixed on the outer wall of the sorting pool 31. The frequency converter 332 can output high-frequency alternating current and direct current. The frequency converter 332 is electrically connected to the control module 5. The coil 333 is rectangular and electrically connected to the frequency converter 332. The coil 333 is slidably disposed on the outer wall of the sorting pool 31. The output end of the lifting drive 331 is fixedly connected to the coil 333. The lifting drive 331 can drive the coil 333 to slide back and forth on the outer wall of the sorting pool 31 in the vertical direction.

[0064] Of course, in other embodiments of this application, the lifting drive 331 can also be configured as other forms of linear drive or linear drive mechanism. For example, the lifting drive 331 can also be configured as a hydraulic cylinder or a motor screw mechanism, as long as it can be connected to the coil 333 and can slide back and forth on the outer wall of the sorting pool 31 in the vertical direction.

[0065] There are two sets of lifting drive components 331 and coils 333, which are symmetrically arranged along the width direction of the sorting pool 31.

[0066] Reference Figure 3 , Figure 4 and Figure 5In this embodiment, the mixing component 34 includes a support beam 341, a rack 346, a gear 347, a displacement drive component 342, a first motor 343, a stirring rod 345, a pressure screen 348, and an elastic component 349. The support beam 341 is disposed on the open end of the sorting tank 31. A rotating shaft 3411 is fixedly disposed on one end of the support beam 341, and a first connecting block 3412 is rotatably disposed on the rotating shaft 3411. A slide rail is fixedly disposed on the open end of the sorting tank 31, and the first connecting block 3412 is slidably connected to the slide rail. A second connecting block 3413 is rotatably disposed on the other end of the support beam 341. The features of the second connecting block 3413 are the same as those of the first connecting block 3412, and the first connecting block 3412 and the second connecting block 3413 are symmetrically disposed along the width direction of the sorting tank 31. The support beam 341 is slidably disposed on the open end of the sorting tank 31 through the first connecting block 3412 and the second connecting block 3413.

[0067] Gear 347 is coaxially fixed on rotating shaft 3411. Gear 347 is located between first connecting block 3412 and support beam 341. Rack 346 is fixed on the open end of sorting pool 31. Rack 346 is located on the side of slide rail near support beam 341. Gear 347 meshes with rack 346.

[0068] The displacement drive 342 is also provided on the opening end of the sorting pool 31. In this embodiment, the displacement drive 342 can also be provided as an electric telescopic cylinder. The output end of the displacement drive 342 is fixedly connected to the first connecting block 3412. The displacement drive 342 can drive the support beam 341 to slide back and forth along the length of the sorting pool 31.

[0069] The first motor 343 is fixed on the support beam 341. The first motor 343 can be configured as a servo motor. The first motor 343 is electrically connected to the control module 5. One end of the stirring rod 345 is provided with a stirring part 3451, and the other end of the stirring rod 345 is connected to the output end of the first motor 343. A limiting block 3454 is fixed on the end of the stirring rod 345 away from the stirring part 3451. The limiting block 3454 is configured as an arc-shaped block, and both ends of the limiting block 3454 along the axial direction of the stirring rod 345 are configured as inclined surfaces, and the two sets of inclined surfaces are arranged in parallel. Two sets of limiting blocks 3454 are arranged circumferentially on the stirring rod 345. A limiting groove 3455 is formed between the two sets of limiting blocks 3454. The limiting groove 3455 and the stirring part 3451 are located on the same horizontal line. The limiting groove 3455 is directly opposite the stirring part 3451. There are also two sets of corresponding limiting grooves 3455 on the stirring rod 345. The two sets of limiting grooves 3455 are arranged circumferentially on the stirring rod 345.

[0070] A limiting sleeve 3456 is provided on the side of the support beam 341 near the separation tank 31. The limiting sleeve 3456 is coaxially sleeved on the stirring rod 345. The diameter of the limiting sleeve 3456 is larger than the diameter of the limiting block 3454. One end of the limiting sleeve 3456 is fixedly connected to the support beam 341. An anti-detachment ring 3457 is fixedly provided at the other end of the limiting sleeve 3456. Two sets of limiting rods 3458 are fixedly provided on the inner wall of the end of the limiting sleeve 3456 with the anti-detachment ring 3457. The two sets of limiting rods 3458 are arranged in a circle on the stirring rod 345. One set of limiting rods 3458 is slidably connected to one set of limiting grooves 3455.

[0071] A connecting groove 3453 is provided at the end of the stirring rod 345 away from the stirring section 3451. A transmission block 3431 is fixedly mounted on the output end of the first motor 343. The transmission block 3431 is hexagonal prism shaped. The connecting groove 3453 is adapted to the shape of the transmission block 3431, and the transmission block 3431 and the connecting groove 3453 are slidably inserted into each other. In addition, a return spring is provided at the end of the stirring rod 345 with the connecting groove 3453. The return spring is located inside the limiting sleeve 3456. One end of the return spring is connected to the output end of the first motor 343, and the other end of the return spring is connected to the end of the stirring rod 345 with the connecting groove 3453.

[0072] The pressure screen 348 is a rectangular plate. The pressure screen 348 is lifted and slidably disposed in the sorting tank 31. The pressure screen 348 is disposed between the support beam 341 and the partition plate 312, and is located above the feeding port 313. A clearance groove 3481 is provided through the pressure screen 348. A shielding curtain 3482 is fixed in the clearance groove 3481. An abutment part 3483 is fixed on the side of the pressure screen 348 near the support beam 341. An abutment seat 3452 is provided on the stirring rod 345. The abutment seat 3452 is rotatably connected to the stirring rod 345, and is located between the limiting block 3454 and the stirring part 3451. The abutment seat 3452 is truncated cone-shaped.

[0073] In this embodiment, the shielding curtain 3482 is made of a flexible material, such as hard rubber, and multiple sets of bristles are fixed to the ground and top surfaces of the shielding curtain 3482. Elastic members 349 are located at the corners of the pressure screen 348. The elastic members 349 can be tension springs. One end of the elastic member 349 is fixedly connected to the pressure screen 348, and the other end is fixedly connected to the inner wall of the sorting tank 31. Four sets of elastic members 349 are provided, each located at one of the four corners of the pressure screen 348.

[0074] In this embodiment, the initial position of the pressure screen 348 is set at three-quarters of the height of the sorting tank 31, the initial state of the stirring rod 345 is horizontal, that is, the axial direction of the stirring rod 345 is parallel to the horizontal direction, and the stirring part 3451 on the stirring rod 345 is also vertical. The initial position of the support beam 341 is also close to one side of the length direction of the sorting tank 31.

[0075] Reference Figure 3 In this embodiment, the discharge assembly 35 includes a blocking drive 351, a blocking plate 352, a discharge hopper 353, a baffle 354, and a third motor 355. A discharge port 314 is provided on the wide side of the sorting pool 31, and a relief groove 315 is provided on the inner bottom wall of the discharge port 314. One end of the blocking plate 352 is slidably disposed in the relief groove 315. The blocking drive 351 is fixedly disposed on the sorting pool 31. The blocking drive 351 can also be configured as an electric telescopic cylinder. The blocking drive 351 is electrically connected to the control module 5. The output end of the blocking drive 351 is fixedly connected to the end of the blocking plate 352 away from the relief groove 315.

[0076] The discharge hopper 353 is fixed on the outer wall of the sorting tank 31. The discharge hopper 353 is located below the discharge port. Two sets of feed pipes 356 are fixed at one end of the discharge hopper 353 away from the sorting tank 31. The two sets of feed pipes 356 are symmetrically arranged along the width direction of the discharge hopper 353.

[0077] A baffle 354 is rotatably mounted at the end of the discharge hopper 353 away from the sorting tank 31. One end of the baffle 354 rotatably abuts against the inner wall of the discharge hopper 353. The baffle 354 is located between the two sets of feed pipes 356 and can selectively block one of the two sets of feed pipes 356. A third motor 355 is fixedly mounted on the discharge hopper 353. The third motor 355 can be configured as a servo motor. The third motor 355 is electrically connected to the control module 5. The output end of the third motor 355 is fixedly connected to the baffle 354, and the third motor 355 can drive the baffle 354 to rotate inside the discharge hopper 353.

[0078] More specifically, a batch of plastic film fragments, cleaned by the cleaning mechanism 2, are fed into the sorting tank 31 through the feeding port 313. At this time, the lifting drive 362 is in a retracted state, and the screening screen 361 is located on the partition plate 312. After the plastic film fragments are completely fed into the sorting tank 31, the control module 5 controls the electronic control valve to close. Then, the control module 5 starts the injection pump to inject sorting liquid into the sorting tank 31. As the sorting liquid is continuously injected, most of the plastic film fragments float on the liquid surface until this part of waste plastic film reaches the position of the pressure screen 348. The controller closes the injection pump and controls the displacement drive 342 to drive the first connecting block 3412 to slide on the opening end of the sorting tank 31. The support beam 341 gradually approaches the center line position in the length direction of the sorting tank 31. Since the gear 347 meshes with the rack 346, the support beam 341 will continuously deflect to one side during the movement, so that the stirring rod 345 gradually changes from a horizontal state to a vertical state.

[0079] During the deflection of the stirring rod 345, the abutment seat 3452 on the stirring rod 345 will gradually abut against the abutment part 3483 on the pressing screen 348. As the stirring rod 345 continues to deflect, the abutment seat 3452 will gradually press the pressing screen 348 downward. At the same time, the connecting groove 3453 and the transmission block 3431, which were originally separated from each other, are inserted into the connecting groove 3453 due to the mutual abutment action between the abutment seat 3452 and the abutment part 3483. When the stirring rod 345 is completely vertical, the pressing screen 348 will press all the plastic film fragments into the sorting liquid, and the stirring rod 345 will also extend into the sorting liquid through the clearance groove 3481.

[0080] Subsequently, the control module 5 controls the lifting drive 331 to move the coil 333 to the lower part of the sorting tank 31, starts the first motor 343, and the stirring rod 345 stirs the film fragments in the sorting tank 31. At the same time, the frequency converter 332 is started to output high-frequency voltage, and the coil 333 applies a high-frequency alternating magnetic field to the inside of the sorting tank 31. Since the sorting liquid contains a certain amount of MnFe2O4, and MnFe2O4 is a magnetic ferrite nanoparticle, it is insoluble in water and will be induced to produce a magnetocaloric effect in the high-frequency alternating magnetic field.

[0081] The magnetocaloric effect refers to the phenomenon where, in a high-frequency alternating magnetic field, the magnetic moment inside a particle attempts to rotate to follow the rapidly reversing direction of the external magnetic field. Meanwhile, the particle's physical rotation in a viscous medium attempts to align with the magnetic field, but due to environmental resistance, it lags behind the changes in the magnetic field. This lag results in hysteresis loss, efficiently converting electromagnetic energy into heat.

[0082] Meanwhile, some plastic film is severely aged due to long-term exposure to the ground, resulting in numerous micropores, cracks, and rough surfaces. This part of the film is also in direct contact with crops, and a large amount of plant residues are attached to it, providing more adsorption sites for nanoparticles. In contrast, some plastic film buried in the soil is not directly exposed to the ground surface, so it is less aged, has a dense surface structure, and fewer adsorption sites. Therefore, during the stirring process of the stirring rod 345, the plastic film exposed to the ground surface will adsorb a large number of nanoparticles compared to the plastic film buried in the soil.

[0083] At this time, with the continuous stirring of the mulch film fragments and the high-frequency alternating magnetic field applied to the sorting tank 31, the liquid around the nanoparticles on the severely aged mulch film fragments is heated extremely quickly to above its boiling point, forming micron-sized steam bubbles near the particles. Under the continuous action of the high-frequency magnetic field, these microbubbles will undergo rapid expansion and contraction. When the bubbles contract to their limit, they will violently implode and collapse, producing cavitation. At the moment of collapse, these bubbles will release strong shock waves, forming high-speed microjet streams, thereby peeling off the plant residues attached to the mulch film. Macroscopically, this manifests as strong mechanical vibration and noise.

[0084] Once the photosensitive plate 322 installed in the sorting tank 31 detects that the mixing in the sorting tank 31 is complete, the specific mixing time is adaptively set according to the total amount of plastic film fragments actually put into the sorting tank 31. The control module 5 controls the first motor 343 to turn off. Then, the displacement drive component 342 drives the support beam 341 to slide to one side of the sorting tank 31, the stirring rod 345 deflects upward, and the transmission block 3431 gradually disengages from the connecting groove 3453. During this process, due to the avoidance groove 3481 on the pressing mesh 348, The opening width is limited, allowing the stirring part 3451 to pass through only when it is in a vertical position. However, it cannot be guaranteed that the first motor 343 will stop in the same position each time it stops. Therefore, as the transmission block 3431 gradually separates from the connecting groove 3453, the limiting rod 3458 will abut against the inclined surface of one end of the limiting block 3454 first, so that the limiting rod 3458 slides into the limiting groove 3455, thereby forcibly adjusting the state of the stirring part 3451 to a vertical state to ensure that the stirring rod 345 can be reset smoothly.

[0085] Next, the injection pump is started to continue injecting the sorting liquid into the sorting tank 31. At this time, the output power of the injection pump is much smaller than the previous output power. The purpose of this setting in this embodiment is to adjust the water outlet speed of the nozzle 3111 on the drain pipe 311 to the minimum fluidization speed suitable for sorting the film fragments.

[0086] The sorting principle is based on the fact that, within the same usage time, the degree of aging of plastic film varies at different locations, resulting in changes in its density. Plastic film exposed to the surface is severely aged, and its density decreases accordingly. In contrast, plastic film buried in the soil has a limited degree of aging, and its density changes less. Similarly, in a flowing fluid, when the fluid passes upwards through stationary solid particles at a certain critical velocity, the drag force of the fluid on the particles gradually counteracts the particles' own weight. Therefore, the minimum fluidization velocity of the corresponding intact plastic film fragments can be calculated based on the initial density of the recovered plastic film, combined with the Ogun equation used to calculate the minimum fluidization velocity.

[0087] Of course, considering that actual plastic film fragments are not three-dimensional particles, the equivalent diameter is selected instead of the particle size in actual operation. For example, in this implementation, the waste plastic film is finally broken into fragments of 5mm×5mm×0.02mm, at which point the actual volume is 0.5mm³, and the equivalent diameter is 1mm. Under this premise, the film fragments with a density lower than the initial density of the plastic film will be more easily affected by the fluid and float, while those with a density similar to the initial density of the plastic film are less likely to sink with the fluid movement.

[0088] Furthermore, the lifting drive 331 will cause the coil 333 to move upward, and the control module 5 will control the DC power of the frequency converter 332. At this time, the coil 333 will transform into an electromagnet. Since the aged film is more likely to adsorb magnetic ferrite nanoparticles, and the magnetic ferrite nanoparticles will be affected by the magnetism of the coil 333, coupled with the large amount of magnetic ferrite nanoparticles adsorbed by the aged film, it will be easier to float. On the contrary, since the density of the plant residue itself is much greater than that of the mulch film, and the plant residue is extremely easy to absorb water, even if it adsorbs magnetic ferrite nanoparticles, it is not easy to float. Instead, it will settle at the bottom of the sorting tank 31 along with the lightly aged mulch film fragments.

[0089] When the photosensitive sensor in a certain area of ​​the photosensitive plate 322 stably detects the light emitted by the light curtain 321 in the sorting liquid, it means that the stratification is completed. Based on the area of ​​the light curtain 321 detected by the photosensitive plate 322, the thickness and position of the floating mulch film fragments can be detected. Then, the control module 5 controls the output end of the individual blocking drive 351 to extend downward, and the discharge port 314 opens. The severely aged mulch film fragments floating upward are discharged from the discharge pipe on one side. Then, the lifting drive 362 drives the screening screen plate 361 to lift upward, sending the mulch film fragments that were originally at the bottom to the discharge port 314 and discharged through the discharge pipe on the other side. Since the screening screen plate 361 restricts the passage of mulch film fragments, and the plant residues after cavitation peeling and stirring are all smaller than mulch film fragments and are filtered out by the screening screen plate 361, thus settling at the bottom of the sorting tank 31. Finally, after each sorting is completed, the sorting liquid and the sediment at the bottom of the sorting tank 31 are discharged into the waste liquid tank for subsequent processing.

[0090] In this embodiment, a pusher plate for assisting in the discharge of plastic film fragments is also installed in the sorting tank. The pusher plate is driven by a linear drive unit installed on the sorting tank, and the pusher plate moves back and forth along the length of the sorting tank. The linear drive unit can be set as a long-stroke hydraulic cylinder. The pusher plate and the linear drive unit are not shown in the attached drawings of this embodiment.

[0091] Reference Figure 5 In this embodiment, the granulation mechanism 4 is provided in two sets, and the two sets of granulation mechanisms 4 are arranged in a one-to-one correspondence with the two sets of discharge pipes. The granulation mechanism 4 includes a washing conveyor belt 41 and a granulation extruder 42. The washing conveyor belt 41 is located on the side of the sorting tank 31 away from the washing water tank 22, and one end of the washing conveyor belt 41 is set as the third feeding end, and the other end of the washing conveyor belt 41 is set as the third discharge end. The third feeding end of the washing conveyor belt 41 is located below the discharge pipe. The mulch film fragments sorted by the sorting tank 31 are conveyed into the granulation extruder 42 through the washing conveyor belt 41 for melt granulation.

[0092] The washing conveyor belt 41 is equipped with a washing pipe, which can spray dilute hydrochloric acid solution onto the plastic film fragments on the washing conveyor belt 41 to remove residual MnFe2O4 on the plastic film fragments. The hydrochloric acid and water will be directly evaporated at high temperature in the granulation extruder 42.

[0093] The implementation principle of the fully automated agricultural waste plastic film recycling system in this application embodiment is as follows: The agricultural waste plastic film is first pre-cleaned to remove surface impurities, then enters the crushing mechanism 1: the hydraulic slitting machine 11 cuts the film into uniform fragments, which are then initially crushed by the tearing machine 12, and finally finely pulverized into uniformly sized film fragments by the crusher 13. The fragments are sequentially sprayed and rubbed by three sets of friction washing machines 21, and the sediment is separated by buoyancy in the series-connected washing tank 22. Residual plant debris is removed by the scraping roller. The cleaned fragments are then placed in the sorting tank 31, where a suspension containing MnFe2O4 nanoparticles is injected. The pressing screen 348 presses the fragments below the liquid surface, and the stirring rod 345 moves at high speed in a magnetic field. Agitation—A high-frequency alternating magnetic field excites nanoparticles to generate a magnetocaloric effect, forming microbubbles on the surface of the aged film. The cavitation shock waves generated by the collapse of these bubbles peel off the attached plant residues. Subsequently, a sorting liquid is injected at a low speed. The injection of the sorting liquid at a fluidized state causes the aged film (low density) that adsorbs nanoparticles to float to the surface, while the intact film and residues sink to the bottom. The photosensitive plate 322 monitors the stratification status in real time. The floating aged film is discharged through the discharge pipe on one side of the discharge hopper 353, while the sinking material is separated by a screen, and the intact film fragments are output from the discharge pipe on the other side. Finally, the two types of fragments are washed with dilute hydrochloric acid to remove magnetic particles and then sent to the granulation extruder 42 for melting and regeneration into pure plastic granules, realizing the fully automated resource recycling of waste plastic film.

[0094] This application also discloses an application method for a fully automated system for processing and recycling agricultural waste plastic film, which includes the following steps:

[0095] S1. Pre-cleaning treatment: All waste plastic film is pre-cleaned before entering the crushing unit 1.

[0096] S2. Crushing process: The pre-cleaned waste plastic film is cut into pieces of similar size by a hydraulic slitting machine 11. These plastic film pieces are then fed into a tearing machine 12 for preliminary crushing. The torn fragments are then fed into a crusher 13 to be crushed into uniformly sized fragments.

[0097] S3. Deep cleaning: The fragments enter three sets of friction washing machines 21 connected in series. The spiral feeding rod in the inclined washing cylinder pushes the fragments to roll. The spray pipe sprays water to wash them, and the drain hole discharges the sewage, removing residual soil, gravel and plant residues.

[0098] Subsequently, the plastic film fragments enter three sets of connected washing water tanks 22. The fragments float on the water surface, while solid impurities sink to the bottom. The elevator 23 then transfers the fragments.

[0099] S4. Sorting process: The cleaned fragments enter the sorting tank 31 through the feeding port 313, and the nozzle 3111 injects a suspension containing MnFe2O4 nanoparticles into the sorting tank 31.

[0100] The control module 5 drives the support beam 341 to move, the stirring rod 345 deflects and extends into the sorting tank 31, and the pressure screen 348 is pressed down simultaneously to immerse the fragments into the sorting liquid. The stirring rod 345 starts to stir the fragments, and the coil 333 applies a high-frequency alternating magnetic field to the sorting liquid. The MnFe2O4 particles generate a magnetothermal effect, forming microbubbles on the surface of the aging film and cavitating and bursting to peel off the plant residues.

[0101] S5. Layered sorting: Continue to inject sorting liquid at a low speed and adjust to the minimum fluidization rate: severely aged fragments float to the top; slightly aged fragments sink to the bottom; plant residues sink to the bottom; switch the DC current of coil 333 to an electromagnet to enhance the magnetic adsorption of floating fragments.

[0102] S6. Layer detection and discharge: The light curtain 321 and photosensitive plate 322 detect the layer position. First, open the discharge port 314. Severely aged fragments are discharged through the discharge hopper 353 and the distribution pipe 356 on one side. Lift the screening screen plate 361. The third motor 355 drives the baffle 354 to deflect. Slightly aged fragments are discharged through the distribution pipe 356 on the other side.

[0103] S7. Granulation process: The sorted fragments are transferred by the washing conveyor belt 41, during which dilute hydrochloric acid solution is sprayed to dissolve the residual MnFe2O4 nanoparticles; then the fragments are put into the granulation extruder 42, melted into a melt at high temperature, and the melt is extruded, cooled and granulated to form recycled granules.

[0104] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A fully automated system for processing and recycling waste agricultural film, characterized in that, include: The system includes a crushing mechanism for uniformly crushing waste plastic film, a cleaning mechanism for cleaning the crushed waste plastic film, a sorting mechanism for sorting waste plastic film of different aging degrees, and a granulation mechanism for granulating waste plastic film slag. The cleaning mechanism is located on one side of the crushing mechanism, the sorting mechanism is located on the side of the cleaning mechanism away from the crushing mechanism, and the granulation mechanism is located on one side of the sorting mechanism. The sorting mechanism includes a sorting pool and a detection component. A control module is provided on one side of the sorting pool. A drain pipe is provided inside the sorting pool. A partition plate is provided inside the sorting pool. The partition plate is located above the drain pipe. A nozzle is provided on the drain pipe. A receiving groove is provided through the partition plate. The nozzle is movably connected to the receiving groove. The nozzle can inject sorting liquid into the sorting pool at a certain critical flow rate. Waste plastic film with different aging degrees will naturally separate into layers in the sorting liquid. The detection component is disposed on the inner wall of the sorting tank, and the detection component is capable of detecting the position of different aged waste plastic film in the sorting tank; The sorting mechanism includes a magnetic separation component, which includes a lifting drive, a frequency converter, and a coil. The sorting liquid in the sorting tank is a suspension prepared by mixing deionized water and MnFe2O4. The lifting drive and the frequency converter are both located on the outer wall of the sorting tank. The lifting drive is electrically connected to the control module. The frequency converter can output high-frequency alternating current and direct current. The coil is electrically connected to the frequency converter and slides on the outer wall of the sorting tank. The output end of the lifting drive is fixedly connected to the coil. The lifting drive can drive the coil to slide back and forth on the outer wall of the sorting tank in a vertical direction.

2. The fully automated system for processing and recycling farmland waste plastic film according to claim 1, characterized in that: The detection component includes a light curtain and a photosensitive plate. The light curtain and the photosensitive plate are respectively fixedly embedded in the inner wall of the long side of the sorting pool, and the light curtain and the photosensitive plate are symmetrically arranged along the width direction of the sorting pool. The light-emitting surface of the light curtain is flush with the inner wall of the sorting pool. Several sets of photosensitive sensors are integrated on the photosensitive plate. The photosensitive plate is electrically connected to the control module, and the photosensitive surface on the photosensitive plate is flush with the inner wall of the sorting pool.

3. The fully automated system for processing and recycling farmland waste plastic film according to claim 2, characterized in that: The sorting mechanism further includes a mixing component, which comprises a support beam, a displacement drive, a first motor, a stirring rod, a rack, and a gear. The support beam is disposed on the open end of the sorting tank, and the displacement drive is disposed on one side of the open end of the sorting tank. A rotating shaft is fixedly mounted on one end of the support beam, and a first connecting block is rotatably mounted on the rotating shaft. The first connecting block is slidably disposed on the open end of the sorting tank, and the output end of the displacement drive is connected to the first connecting block. A second connecting block is rotatably mounted on the other end of the support beam, and the second connecting block is slidably disposed on the open end of the sorting tank. The connecting block and the second connecting block are symmetrically arranged along the width direction of the sorting pool. The first motor is fixed on the support beam and is electrically connected to the control module. One end of the stirring rod is provided with a stirring part, and the other end of the stirring rod is connected to the output end of the first motor. The gear is fixed on the rotating shaft, and the rack is fixed on the opening end of the sorting pool. The gear meshes with the rack. When the displacement driving member drives the support beam to slide along the length direction of the sorting pool, the support beam deflects to one side under the action of the gear, thereby causing the stirring rod to extend into the sorting pool for stirring.

4. The fully automated system for processing and recycling farmland waste plastic film according to claim 3, characterized in that: The mixing assembly also includes a pressure screen and an elastic element. The pressure screen is rectangular in shape. A feeding port is provided on the sorting tank. The pressure screen is lifted and slidably disposed in the sorting tank. The pressure screen is disposed between the support beam and the partition plate. The pressure screen is located above the feeding port. An avoidance groove is provided through the pressure screen. A shielding curtain is provided in the avoidance groove. An abutment part is fixed on the side of the pressure screen near the support beam. An abutment seat is rotatably disposed on the stirring rod. The elastic element is disposed on the pressure screen. One end of the elastic element is fixedly connected to the pressure screen, and the other end of the elastic element is fixedly connected to the inner wall of the sorting tank. When the stirring rod extends into the sorting tank for stirring, the abutment seat squeezes the abutment part, thereby causing the pressure screen to press the waste film floating on the surface into the sorting liquid.

5. The fully automated system for processing and recycling farmland waste plastic film according to claim 4, characterized in that: A connecting groove is formed on the end face of the stirring rod away from the stirring part. A transmission block is fixed on the output end of the first motor. The transmission block is movably inserted into the connecting groove. A limiting block is fixed on the end of the stirring rod with the connecting groove. The limiting block is an arc-shaped block, and both ends of the limiting block along the axis of the stirring rod are set as inclined surfaces. Two sets of limiting blocks are arranged on the circumference of the stirring rod, and a limiting groove is formed between the two sets of limiting blocks. The limiting groove is directly opposite the stirring part. A limiting sleeve is provided on the support beam. The limiting sleeve is coaxially sleeved on the stirring rod. The limiting block and the limiting sleeve are slidably connected. One end of the limiting sleeve is fixedly connected to the support beam. An anti-detachment ring is fixed at the other end of the limiting sleeve. Two sets of limiting rods are arranged on the circumference of the inner wall of the end of the limiting sleeve with the anti-detachment ring, and the limiting rods are slidably connected to the limiting groove.

6. The fully automated system for processing and recycling farmland waste plastic film according to claim 5, characterized in that: The sorting mechanism further includes a discharge assembly, which comprises a blocking drive, a blocking plate, a discharge hopper, a baffle, and a third motor. A discharge port is provided on the wide side of the sorting pool, and a clearance groove is provided on the inner wall of the discharge port. One end of the blocking plate is slidably disposed within the clearance groove. The blocking drive is disposed on the opening end of the sorting pool and is electrically connected to the control module. The output end of the blocking drive is fixedly connected to the blocking plate. The discharge hopper is fixedly disposed on the outer wall of the sorting pool, located below the discharge port, and facing away from one side of the sorting pool. Two sets of feed pipes are fixedly provided at one end of the discharge hopper. The two sets of feed pipes are symmetrically arranged along the width direction of the discharge hopper. A baffle is rotatably disposed at the end of the discharge hopper away from the sorting tank. One end of the baffle rotatably abuts against the inner wall of the discharge hopper. The baffle is located between the two sets of feed pipes and can selectively block one of the two sets of feed pipes. A third motor is fixedly disposed on the discharge hopper and electrically connected to the control module. The output end of the third motor is connected to the end of the baffle that abuts against the inner wall of the discharge hopper. The third motor can drive the baffle to rotate inside the discharge hopper.

7. The fully automated system for processing and recycling farmland waste plastic film according to claim 6, characterized in that: The sorting mechanism further includes a discharge assembly, which includes a screening screen and a lifting drive. The screening screen is disposed on the side of the partition plate opposite to the drain pipe. A scraper is fixedly disposed on one side of the screening screen, and the scraper slides against the inner wall of the sorting tank where the light curtain is embedded. Two sets of scrapers are provided, and the two sets of scrapers are symmetrically arranged along the width direction of the sorting tank. The lifting drive is fixedly disposed on the outer wall of the sorting tank, and the output end of the lifting drive is fixedly connected to the screening screen. The lifting drive can drive the screening screen to reciprocate vertically within the sorting tank.

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