Apparatus and method for sorting plastic film pieces from residue film

Abstract

The present application relates to the field of waste plastic sorting, and discloses an apparatus and method for sorting plastic film pieces from residual film. The apparatus comprises: a crushing device for crushing residual film material; a vibrating sieve separation device comprising a plurality of sieve plates arranged vertically at intervals, each sieve plate being arranged obliquely relative to the horizontal direction, the high end of the uppermost sieve plate forming a feed end in communication with the discharge port of the crushing device, and the sieve hole diameters of the plurality of sieve plates decreasing in turn from top to bottom; a plurality of plastic film separation devices corresponding to the plurality of sieve plates for separating plastic film pieces from the material on the corresponding sieve plate; and a plastic film refining device for separating and purifying the plastic film pieces from the plurality of plastic film separation devices. The apparatus and method of the present application can effectively solve the problems of recovering plastic film pieces from waste residual film and backfilling of lost soil and biomass in residual film.

Description

Technical Field

[0001] This invention relates to the field of waste plastic sorting, and more specifically to a device and method for sorting plastic film sheets from residual film. Background Technology

[0002] Cotton and other crops require a large amount of plastic film and greenhouse film during cultivation, but these materials cannot be completely recycled after use. Unrecycled film residue in the topsoil layer not only hinders water movement and reduces soil permeability, but also affects air permeability and the normal activity of soil microorganisms, leading to difficulties in nutrient transport and impacting seedling emergence and normal crop growth.

[0003] To reduce the residual plastic film content in the soil, it is currently mostly recycled using residual plastic film recycling machines. However, this also leads to the loss of a large amount of arable land soil. If the plastic film inside the residual film cannot be effectively separated, the disposal of the residual film is also a problem. In addition, plastic itself is a high-quality hydrocarbon resource. Separating the plastic from the residual film and reusing it effectively can alleviate the national energy crisis to some extent and ensure national energy security.

[0004] Currently, the sorting technology for recovering plastics from residual film is not mature. CN114474487A provides a residual film processing, sorting, and reuse production line, including the following process steps: S1, using a film shredder to break and shred the film; S2, screening through a vibrating screen; S3, introducing the mixture into an air-separation hopper; S4, performing air separation, where the cotton stalks and cotton fibers in the residual film mixture are discharged, and the mixture enters a straw-film separation device to extract the film; S5, conveying the mixture to a drum screen, where the air-separation machine sends the film extracted from the residual film mixture through the discharge port into the drum screen for processing, where the very small cotton stalk and wood chips on the film surface are screened out by rotating and falling within the drum screen. However, this production line uses a vibrating screen for separating small-sized materials and an air-separation machine to discharge cotton stalks and cotton fibers from the residual film mixture. The cotton stalks, wood chips, and other materials will contain a large number of small-sized plastic film flakes, which may be insufficient to meet the backfilling requirements of lost soil.

[0005] CN207022399U provides a method for separating residual film from impurities. This method utilizes the different physical properties of the components in the residual film mixed with impurities, combining screening and air separation to separate and collect the residual film. The residual film and impurities are poured into the upper part of an inclined vibrating screen. An air separation chamber is set directly above the lower part of the vibrating screen. When the vibrating screen and air separation chamber operate simultaneously, the heaviest stones and soil clods leak out through the gaps between the vibrating screen bars. Medium-heavy impurities undergo parabolic motion within the air separation chamber, eventually flowing to the lower edge of the vibrating screen. The lightest residual film and fine impurities flow along the air separation chamber into a mesh residual film frame. Due to the wind force, the residual film adheres to the mesh residual film frame, while the fine impurities are blown out, thus achieving the separation of residual film and impurities. However, apart from stones and soil, all other materials are separated by air separation chamber. A large number of plastic films and other impurities accumulate on the mesh residual film frame. Not only is the impurity content of the collected plastic films high, but the mesh residual film frame also needs to be replaced constantly to maintain continuous operation. At the same time, a large amount of airflow mixed with fine impurities flows into the air, causing air pollution. Summary of the Invention

[0006] The purpose of this invention is to solve the problems of high impurity content in plastic films recycled from waste film residues and the backfilling of soil and biomass lost from the residues in the existing technology.

[0007] To achieve the above objectives, the present invention provides an apparatus for sorting plastic film sheets from residual film, comprising:

[0008] Crushing device, the crushing device being used to crush residual film material;

[0009] A vibrating screening device includes multiple screen plates arranged at intervals along the vertical direction. Each screen plate is inclined relative to the horizontal direction. The uppermost screen plate forms a feed end that communicates with the discharge port of the crushing device. The screen aperture of the multiple screen plates decreases sequentially from top to bottom.

[0010] Multiple plastic film separation devices are provided, each corresponding to a set of screen plates, for separating plastic film sheets from the material on the respective screen plates; and

[0011] A plastic film refining device is used to separate and purify plastic films from a plurality of said plastic film separation devices.

[0012] The equipment of this invention uses a crushing device to crush residual film material, which not only facilitates the separation of plastic film sheets from the residual film but also loosens the compacted residual film mixture, making it easier for downstream processes to separate. By using multi-layer sieves to classify the residual film material according to size, and by incorporating corresponding plastic film separation devices to separate the plastic film sheets on each sieve layer, it enables the separation of materials of different sizes and compositions under differentiated operating conditions, thereby reducing the impurity content in the separated plastic film sheets and the plastic film content within the impurities. A plastic film refining device further separates and purifies the separated plastic film sheets, further reducing the impurity content. Therefore, the equipment of this invention effectively solves the problems of recovering plastic film sheets from waste residual film and the backfilling of soil and biomass lost within the residual film.

[0013] In some embodiments, the device further includes a feeding conveyor for conveying residual film material to the crushing device.

[0014] In some embodiments, the crushing device is configured to crush the residual film material to an average long side dimension of 2cm-10cm, preferably 3cm-8cm.

[0015] In some embodiments, the tilt angle of the sieve plate is 0.01-30°.

[0016] In some embodiments, the sieve aperture of the uppermost sieve plate is 0.2cm-6cm, and the sieve aperture of the remaining sieve plates is 0.01cm-3cm.

[0017] In some embodiments, the plastic film separation device includes a suction or blowing device, preferably, the gas linear velocity of the suction or blowing device is in the range of 5m / s-30m / s.

[0018] In some embodiments, the vibrating screening device further includes a first conveying section disposed at intervals below the plurality of screen plates, the first conveying section being used to receive and convey outward the material screened off by the lowest screen plate.

[0019] In some embodiments, the discharge port of the crushing device is located at the bottom of the crushing device, and the discharge port is positioned directly opposite the feed end.

[0020] In some embodiments, the device further includes a second conveying section for conveying material on the uppermost screen plate back to the crushing device.

[0021] In some embodiments, the device further includes a third conveying unit for conveying material outward from each of the screen plates except the uppermost screen plate.

[0022] Another aspect of the present invention provides a method for sorting plastic film sheets from residual film, comprising the following steps:

[0023] S1. Crush the residual film material to an average long side dimension of 2cm-10cm;

[0024] S2. The crushed residual film particles are classified according to size and screened in multiple stages.

[0025] S3. Separate the plastic film from the multi-stage materials after screening;

[0026] S4. The separated plastic membranes are further separated and purified.

[0027] The method of the present invention has the same advantages as the device, which will not be repeated here.

[0028] In some embodiments, the method further includes, after step S3, crushing and separating the primary material after the separation of the plastic film again according to steps S1-S4.

[0029] In some embodiments, the method further includes a step of discharging the remaining material after the separation of the plastic film following step S3.

[0030] In some embodiments, in step S1, the residual film material is crushed to an average long side dimension of 3cm-8cm.

[0031] In some embodiments, the plastic film is separated in step S3 by suction or blowing. Preferably, the linear velocity of the gas in the suction or blowing process is in the range of 5-30 m / s.

[0032] In some embodiments, the method is performed using the aforementioned equipment for sorting plastic film sheets from residual film.

[0033] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0034] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0035] Figure 1 This is a schematic diagram of one embodiment of the device for sorting plastic films from residual film in this invention.

[0036] Explanation of reference numerals in the attached figures

[0037] 1- Crushing device, 2- Vibrating screening device, 21- Screen plate, 22- First conveying unit, 3- Plastic film separation device, 4- Plastic film refining device. Detailed Implementation

[0038] The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. The following detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of the present invention by way of example, but should not be used to limit the scope of the present invention. The present invention can be implemented in many different forms and is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0039] These embodiments are provided to make the invention thorough and complete, and to fully express the scope of the invention to those skilled in the art. It should be noted that, unless otherwise specifically stated, the relative arrangement of components and steps, material composition, numerical expressions, and values ​​set forth in these embodiments should be interpreted as merely exemplary and not as limiting.

[0040] It should be noted that, in the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicating orientation or positional relationships, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0041] Furthermore, the terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. "Vertical" is not strictly vertical, but within the permissible range of error. "Parallel" is not strictly parallel, but within the permissible range of error. Terms such as "including" or "comprising" mean that the element preceding the word encompasses the element listed after the word, and do not exclude the possibility of encompassing other elements as well.

[0042] It should also be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention depending on the specific circumstances. When a specific device is described as being located between a first device and a second device, an intermediary device may or may not be present between the specific device and the first or second device.

[0043] All terms used in this invention have the same meaning as understood by one of ordinary skill in the art to which this invention pertains, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant art, and not as idealized or highly formalized, unless expressly defined herein.

[0044] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0045] This invention provides, in one aspect, a device for sorting plastic film sheets from residual film, see [link to device]. Figure 1 The device includes:

[0046] Crushing device 1 is used to crush residual film materials (including plastic film, soil and other impurities such as straw and cotton);

[0047] Vibrating screen device 2 includes multiple screen plates 21 arranged at intervals along the vertical direction. Each screen plate 21 is inclined relative to the horizontal direction. The uppermost screen plate 21 forms a feed end that is connected to the discharge port of the crushing device 1. The screen hole diameter of the multiple screen plates 21 decreases from top to bottom.

[0048] Multiple plastic film separation devices 3 are provided, each corresponding to a multiple sieve plate 21, for separating plastic film sheets from the material on the corresponding sieve plate 21; and

[0049] Plastic film refining device 4 is used to separate and purify plastic film sheets from multiple plastic film separation devices 3.

[0050] As described above, it should be noted that the screen plate 21 can vibrate in the vertical and / or horizontal directions. The vibrating screening device 2 may also include a drive mechanism (e.g., a motor) for driving the screen plate 21 to vibrate. The plastic film separation device 3 can separate plastic films over the entire range of the screen plate 21, or it can concentrate the separation of plastic films only at the lower end (i.e., the discharge end) of the screen plate 21. The correspondence between multiple plastic film separation devices 3 and multiple screen plates 21 can be understood as follows: multiple plastic film separation devices 3 and multiple screen plates 21 can be arranged in a one-to-one correspondence, or each screen plate 21 can be equipped with two or more plastic film separation devices 3.

[0051] In operation, the residual film material is first fed into the crushing device 1 for crushing. The crushed material then enters the feed end of the uppermost screen plate 21 of the vibrating screening device 2 through the discharge port of the crushing device 1. As the uppermost screen plate 21 vibrates, it undergoes primary screening, meaning that larger materials remain on the uppermost screen plate 21 and gradually move to the discharge end of the uppermost screen plate 21. Smaller materials fall through the screen holes of the uppermost screen plate 21 onto the lower screen plate 21 for secondary screening, meaning that larger materials remain on the second screen plate 21. The material gradually moves to the discharge end of the second screen plate 21. Smaller materials fall through the screen holes of the second screen plate 21 onto the lower screen plate 21 for three-stage screening, and so on. Then, the plastic film separation device 3 corresponding to each screen plate 21 is used to separate the plastic film from the material on the corresponding screen plate 21. Finally, the plastic film refining device 4 is used to further separate the plastic film separated by the multiple plastic film separation devices 3 (at this time, the plastic film still contains some soil particles) to obtain clean plastic film.

[0052] The equipment of this invention uses a crushing device 1 to crush the residual film material, which not only facilitates the separation of plastic film sheets from the residual film but also loosens the compacted residual film mixture, making it easier for downstream processes to separate. Multiple layers of sieve plates 21 are used to classify the residual film material according to size, and corresponding plastic film separation devices 3 separate the plastic film sheets on each sieve plate 21. This allows for differentiated separation of materials of different sizes and compositions under varying operating conditions, thereby reducing the impurity content in the separated plastic film sheets and the plastic film content within the impurities. A plastic film refining device 4 further separates and purifies the separated plastic film sheets, further reducing the impurity content. Therefore, the equipment of this invention effectively solves the problems of recovering plastic film sheets from waste residual film and the backfilling of soil and biomass lost within the residual film.

[0053] Through extensive research, the inventors discovered that when the size of the crushed residual film material is too large, effective separation of various substances cannot be achieved through vibrating screening and air separation, requiring repeated crushing and vibration separation operations, resulting in high costs and poor separation effects. Conversely, when the size of the crushed residual film material is too small, the plastic film will become entangled with impurities such as straw and cotton, making separation difficult. Therefore, as a preferred embodiment, the crushing device 1 is configured to crush the residual film material to an average long side size of 2cm-10cm (i.e., the average length range of the longest side of the material, which is also the average maximum size range), and more preferably 3cm-8cm.

[0054] In this invention, the discharge port of the crushing device 1 can be located at the bottom of the crushing device 1, and the discharge port of the crushing device 1 is set directly opposite the feed end of the uppermost screen plate. With this arrangement, the material can fall freely to the vibrating screening device 3 under the action of gravity.

[0055] In this invention, preferably, the inclination angle of the sieve plate 21 is 0.01-30°, that is, the angle between the surface of the sieve plate 21 and the horizontal plane is 0.01-30°.

[0056] In this invention, preferably, the sieve aperture of the uppermost sieve plate 21 is 0.2cm-6cm, and the sieve aperture of the remaining sieve plates 21 is 0.01cm-3cm. By setting the above sieve aperture size, and in conjunction with the crushed material size of 2cm-10cm, effective separation of plastic film, soil, and impurities can be achieved.

[0057] In this invention, the vibrating screening device 2 may further include a first conveying section 22 spaced below multiple screen plates 21. The first conveying section 22 is used to receive and convey the material screened off by the lowest screen plate 21. It is understood that the material screened onto the first conveying section 22 is primarily soil particles. The first conveying section 22 can output the soil particles to a fixed position to facilitate the backfilling of the soil particles.

[0058] The device of the present invention may further include a second conveying section and a third conveying section (not shown in the figure). The second conveying section is used to convey the material on the uppermost screen plate 21 back to the crushing device 1 for further crushing; the third conveying section is used to convey the material (mainly impurities) on the remaining screen plates 21 other than the uppermost screen plate 21 to the outside.

[0059] In this invention, the plastic film separation device 3 utilizes the characteristic that plastic films are more easily carried by airflow to separate the plastic films from other substances. For example, the plastic film separation device 3 may include a suction or blowing device. By utilizing the suction or blowing force provided by the suction or blowing device, the lightweight plastic films in the material can be separated. Preferably, the gas linear velocity of the suction or blowing device is in the range of 5 m / s to 30 m / s. It is understood that in the case of a suction device, the gas linear velocity at the inlet of the suction device is in the range of 5 m / s to 30 m / s; in the case of a blowing device, the gas linear velocity at the outlet of the blowing device is in the range of 5 m / s to 30 m / s, that is, the gas linear velocity acting on the material to be separated is in the range of 5 m / s to 30 m / s.

[0060] The device of the present invention may further include a feeding conveying device (not shown in the figure), which is used to convey the residual film material to the crushing device 1. Specifically, the feeding conveying device can be used to convey the residual film material to the crushing device 1 at a uniform speed and continuously to achieve continuous sorting operation, thereby improving separation efficiency. Of course, in other embodiments, the residual film material can be directly poured into the crushing device 1 through the feed inlet, or a feed funnel can be provided at the feed inlet.

[0061] In this invention, such as Figure 1As shown, the crushing device 1 can be located at the upper left of the vibrating screen device 2, and the plastic film separation device 3 can be located at the upper right of the vibrating screen device 2. This can reduce the space occupied by the equipment and achieve the separation of plastic film sheets from the residual film in a limited space.

[0062] In this invention, the crushing device 1 can be any crushing device in the prior art. The plastic film separation device 3 can be any suitable separation device in the prior art, such as a blower that can generate airflow or an exhaust fan that can generate negative pressure (see CN207022399U for details). The plastic film sorting device 4 can separate the plastic film and soil particles by utilizing the differences in density and size, and can be any suitable separation device in the prior art, such as a vibrating screen. The feeding conveying device, the first conveying section, the second conveying section, and the third conveying section can be any equipment or component in the prior art that has a solid conveying function, such as a conveyor belt.

[0063] Another aspect of the present invention provides a method for sorting plastic film sheets from residual film, comprising the following steps:

[0064] S1. Crush the residual film material to an average long side dimension of 2cm-10cm;

[0065] S2. The crushed residual film particles are classified according to size and screened in multiple stages.

[0066] S3. Separate the plastic film from the multi-stage materials after screening;

[0067] S4. The separated plastic membranes are further separated and purified.

[0068] The method may further include, after step S3, crushing and separating the primary material (corresponding to the material on the uppermost sieve plate) after the plastic film has been separated according to steps S1-S4.

[0069] The method may further include a step of discharging the remaining material (i.e., the material on the remaining screen plates excluding the upper screen plate) after separating the plastic film from step S3.

[0070] Preferably, in step S1, the residual film material is crushed to an average long side dimension of 3cm-8cm. In step S3, the plastic film is separated by suction or blowing, preferably with a gas linear velocity range of 5-30m / s.

[0071] The method of the present invention can be performed using the aforementioned equipment for sorting plastic films from residual film. The method of the present invention has the corresponding advantages of the aforementioned equipment, which will not be elaborated further here.

[0072] In this invention, the inventors discovered through extensive research that by controlling the size of the crushed material, the sieve aperture size of each sieve plate, and the gas linear velocity of the plastic film separation device, effective separation of plastic film sheets can be achieved while reducing separation costs. Specifically, the average long side dimension of the crushed material is 2cm-10cm, the sieve aperture of the uppermost sieve plate 21 is 0.2cm-6cm, the sieve aperture of the remaining sieve plates 21 is 0.01cm-3cm, and the gas linear velocity of the plastic film separation device is in the range of 5m / s-30m / s. This allows the impurity content in the plastic film to be less than 10%, and the content of plastic film sheets among other impurities to be less than 1%, enabling the backfilling of lost soil and biomass within the residual film.

[0073] The following examples further illustrate this point.

[0074] Example

[0075] Cotton post-planting film residue was used as raw material for sorting plastic film sheets. After sorting, other impurities and plastic film sheets were collected, and the impurity content was measured.

[0076] Method for measuring impurity content: First, weigh the material to obtain mass m0, then dry it at 60℃ for 8 hours and weigh it again to obtain the material mass m. 10 The material is washed to remove surface impurities and then weighed again to obtain the material mass m. 20 The impurity content of the material is (m 20 -m 10 ) / m0*100%.

[0077] Example 1

[0078] Experimental Method: 1000 kg of residual film raw material was taken, with a plastic film content of 5.26%. The material was crushed by crushing device 1, and the average long side dimension of the crushed material was 6 cm. The vibrating screening device included two layers of screen plates, with the upper screen plate having a screen aperture size of 2 cm and the lower screen plate having a screen aperture size of 0.1 cm. The gas linear velocity of the plastic film separation device was 12 m / s. After separation, the content of impurities (mainly soil particles) in the plastic film was 9.6%, the content of plastic film in other impurities was 0.3%, and the content of plastic film in soil particles was <0.1%.

[0079] Comparative Example 1

[0080] Experimental method: 1000 kg of residual film raw material was taken, with a plastic film content of 5.26%. The equipment and method described in Example 1 were used, the only difference being that the average long side dimension of the crushed material was 12 cm. After separation, the impurity content in the plastic film was 12.7%, the plastic film content in other impurities was 0.8%, and the plastic film content in soil particles was <0.1%.

[0081] Comparative Example 2

[0082] Experimental method: 1000 kg of residual film raw material was taken, with a plastic film content of 5.26%. The equipment and method described in Example 1 were used, the only difference being that the average long side dimension of the crushed material was 1 cm. After separation, the impurity content in the plastic film was 20.8%, the plastic film content in other impurities was 1.7%, and the plastic film content in soil particles was 0.2%.

[0083] Comparative Example 3

[0084] Experimental method: 1000 kg of residual film raw material was taken, with a plastic film content of 5.26%. The equipment and method described in Example 1 were used, the only difference being that the vibrating screening device had only one sieve plate with a sieve aperture size of 10 mm. After separation, the impurity content in the plastic film was 10.8%, the plastic film content in other impurities was 0.7%, and the plastic film content in soil particles was 1.2%.

[0085] Comparative Example 4

[0086] Experimental method: 1000 kg of residual film raw material was taken, with a plastic film content of 5.26%. The equipment and method described in Example 1 were used. The difference from Example 1 is that the vibrating screening device has only one sieve plate with a sieve aperture size of 10 mm; and it does not have a plastic film separation device. After separation, the impurity content in the plastic film was 39.4%, the plastic film content in other impurities was 0.7%, and the plastic film content in soil particles was 1.3%.

[0087] Comparative Example 5

[0088] Experimental method: 1000 kg of residual film raw material was taken, with a plastic film content of 5.26%. The equipment and method described in Example 1 were used, the only difference being that the gas linear velocity of the plastic film separation device was 32 m / s. After separation, the impurity content in the plastic film was 15.1%, the plastic film content in other impurities was 0.2%, and the plastic film content in soil particles was <0.1%.

[0089] Comparative Example 6

[0090] Experimental method: 1000 kg of residual film raw material was taken, with a plastic film content of 5.26%. The equipment and method described in Example 1 were used, the only difference being that the gas linear velocity of the plastic film separation device was 3.5 m / s. After separation, the impurity content in the plastic film was 10.1%, the plastic film content in other impurities was 2.3%, and the plastic film content in soil particles was <0.1%.

[0091] The various embodiments of the present invention have now been described in detail. To avoid obscuring the concept of the invention, some details known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description.

[0092] Although some specific embodiments of the present invention have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Those skilled in the art should understand that modifications can be made to the above embodiments or equivalent substitutions can be made to some technical features without departing from the scope and spirit of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way.

Claims

1. A device for sorting plastic films from residual film, characterized in that, include: Crushing device (1), the crushing device (1) is used to crush residual film material, and is set to crush the residual film material to an average long side size of 2cm-10cm; Vibrating screen device (2), the vibrating screen device (2) includes a plurality of screen plates (21) arranged at intervals along the vertical direction, each screen plate (21) is inclined relative to the horizontal direction, the uppermost screen plate (21) forms a feed end that communicates with the discharge port of the crushing device (1), the screen hole diameter of the plurality of screen plates (21) decreases from top to bottom, the screen hole diameter of the uppermost screen plate (21) is 0.2cm-6cm, and the screen hole diameter of the remaining screen plates (21) is 0.01cm-3cm; Multiple plastic film separation devices (3) are provided, and multiple plastic film separation devices (3) are correspondingly arranged with multiple screen plates (21) to separate plastic film sheets from the material on the corresponding screen plate (21). The plastic film separation device (3) includes a suction or blowing device, and the gas linear velocity of the suction or blowing device is in the range of 5m / s-30m / s. as well as Plastic film refining device (4) is used to separate and purify plastic films from multiple plastic film separation devices (3).

2. The device for sorting plastic films from residual film according to claim 1, characterized in that, The equipment also includes a feeding conveyor for feeding residual film material to the crushing device (1); and / or The crushing device (1) is configured to crush the residual film material to an average long side size of 3cm-8cm.

3. The device for sorting plastic films from residual film according to claim 1, characterized in that, The inclination angle of the sieve plate (21) is 0.01-30°.

4. The device for sorting plastic films from residual film according to claim 1, characterized in that, The vibrating screening device (2) further includes a first conveying section (22) spaced below the plurality of screen plates (21), the first conveying section (22) being used to receive and convey outward the material screened off by the lowest screen plate (21); and / or The discharge port of the crushing device (1) is located at the bottom of the crushing device (1), and the discharge port is set directly opposite the feed end.

5. The apparatus for sorting plastic films from residual film according to any one of claims 1-4, characterized in that, The equipment further includes a second conveying section for conveying material on the uppermost screen plate (21) back to the crushing device (1); and / or The device also includes a third conveying unit for conveying the material on each of the sieve plates (21) except for the uppermost sieve plate (21) to the outside.

6. A method for sorting plastic film sheets from residual film, characterized in that, The method is performed using the equipment for sorting plastic film sheets from residual film as described in any one of claims 1-5, and the method includes the following steps: S1. Crush the residual film material to an average long side dimension of 2cm-10cm; S2. The crushed residual film particles are classified according to size and screened in multiple stages. S3. Separate the plastic film from the multi-stage materials after screening; S4. The separated plastic membranes are further separated and purified.

7. The method for sorting plastic films from residual film according to claim 6, characterized in that, The method further includes, after step S3, crushing and separating the primary material after the separation of the plastic film again according to steps S1-S4, and / or The method further includes a step of discharging the remaining material after the plastic film has been separated following step S3.

8. The method for sorting plastic films from residual film according to claim 6, characterized in that, In step S1, the residual film material is crushed to an average long side size of 3cm-8cm.

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