Standardized preparation method of regenerative cycle material

Abstract

The invention belongs to the technical field of waste plastic recovery, and particularly relates to a standardized preparation method of a regenerative cycle material. The sand blasting stripping machine is used for efficiently removing attached layers such as labels, glue, paint and electroplated coatings on the surface of the waste plastic, then the shredder and the crusher are used for treating materials into crushed pieces with the diameter of 5-30 mm, continuous crushing operation is formed, the size uniformity is ensured, the sand blasting stripping machine adopts the physical impact principle, use of chemical reagents is avoided, and the production cost is reduced. The environmental pollution is reduced, and the high responsibility to the environment is reflected. Through density difference, effective recovery and reutilization of the grinding material are realized by utilizing a solution density sedimentation method, so that the cost is reduced, the resource consumption is reduced, and the concepts of circular economy and low-carbon economy are met.

Description

Technical Field

[0001] The invention belongs to the technical field of waste plastic recycling, and in particular relates to a standardized preparation method for recycled recycling materials. Background Art

[0002] While the popularity of plastics has improved the convenience of life, it has also caused serious environmental problems, especially plastic pollution, which poses a major threat to the global ecological environment. In China, more than 30 million tons of waste plastics are generated each year. Although the recycling rate has reached more than 70%, during the recycling process, the labels, glue, paint, electroplating and other attachments on the waste plastics have become a thorny problem. If these impurities are not completely removed, the quality of the recycled plastics will be greatly reduced, and even because of heavy metal pollution, it will not pass the environmental protection standards, limiting its possibility of reuse.

[0003] The current methods for dealing with waste plastic attachments each have their own drawbacks. First, directly mixing attachments for recycling will lead to a decline in the quality of recycled plastics, and harmful substances such as heavy metals will remain, making the material no longer suitable for use. Secondly, although acid and alkali cleaning can effectively remove the surface attachment layer, this process not only consumes a large amount of water resources, but also generates acidic and alkaline waste liquids. If not handled properly, it will cause new environmental pollution. Finally, although manual polishing avoids the wastewater problem, its inefficiency and non-automatic characteristics make it incapable of large-scale operations.

[0004] In view of this, the plastics industry urgently needs a recycling technology that can not only efficiently treat the surface adhesion layer of waste plastics, but also ensure pollution-free. The ideal solution should be able to improve recycling efficiency and material quality, while meeting environmental protection requirements and avoiding secondary pollution. This is not only related to the sustainable development of the plastics industry, but also an important measure to maintain the ecological balance of the earth.

[0005] A Chinese patent application document (publication number CN113787646A) discloses a method and processing equipment for preparing environmentally friendly plastic materials for recycling and reuse. The invention first clamps a water bucket on a water bucket skin removal machine, peels the water bucket, cuts the water bucket into thin and long plastic strips, and then uses a water bucket crusher to crush it into particles. Through the coordinated use of a primary water pool, a first auger conveyor and a secondary water pool, the plastic particles can be cleaned twice. The plastic particles are then transported to a drying device for drying through a second auger conveyor. While drying, an appropriate amount of a permeability enhancer is added. The plastic particles are then transported to a mixing tank through a third auger conveyor to mix the plastic particles and the permeability enhancer in a certain proportion. The plastic particles are finally transported to an extruder for melting and extrusion molding, and then cut through a cutting granulator. Through the coordinated use of the above equipment, the processes of water bucket recycling, crushing, cleaning, drying, extrusion, granulation, etc. are realized, greatly improving production efficiency. However, this patent can only be applied to bucket cleaning and cannot be used for other waste plastic processing. In addition, the invention uses primary and secondary water pools for cleaning. The cleaning process requires a large amount of water, which can easily cause secondary pollution.

[0006] A Chinese patent application document (publication number CN1464075A) discloses a method for recovering polycarbonate substrates from discarded optical discs. The invention is to place the discarded optical discs in an acid or alkaline cleaning solution, and then use the acid or alkaline cleaning solution to break the UV protective layer into pieces and separate it from the metal film under high temperature and / or ultrasonic action. The metal film is dissolved in the acid or alkaline cleaning solution to obtain the optical disc substrate, and the concentration of the acid or alkaline cleaning solution is above 1wt%. The invention not only solves the environmental pollution problem caused by crushing, landfilling or incinerating optical discs, but also recovers available resources. However, it uses a large amount of acid and alkali solution as a cleaning solvent, which will produce a large amount of acid and alkali waste liquid, which is not conducive to environmental protection.

[0007] The Chinese patent application document (publication number CN105835262A) discloses a dry cleaning system and method for waste plastics. The invented system includes: a solid medium cleaning device, a sorting device, an air medium cleaning device and a dust removal device. The cleaning method includes the following steps: using sand and gravel to remove the attachments on the surface of the waste plastics, separating the sand and gravel from the cleaned waste plastics through the sorting device, recycling the sand and gravel, and the cleaned waste plastics enter the air medium cleaning device to clean the floating dust on the surface of the waste plastics; finally, the gas discharged from the air medium cleaning device is dusted in the dust removal device. However, the dry friction cleaning described therein generates heat, especially when removing foreign matter adhered to adhesives, which requires high speed and long friction time to remove, which will cause softening and agglomeration of the waste plastics.

[0008] The Chinese patent application document (CN117047938A) discloses a method and process for preparing waste recycled plastics, which includes the following steps: crushing and sorting, dry sorting, waterless cleaning, wet sorting, plastic enrichment purification, and modified granulation; the crushing and sorting includes: crushing the plastic parts and removing the iron therein by magnetic separation, and then performing eddy current sorting to obtain copper, aluminum, and an adhesive of insulating plastic sheets and foam cotton. However, the sorting process uses multiple flotation treatments, which wastes and pollutes a large amount of water resources, and the hard inorganic particles cannot be recycled after friction. Summary of the invention

[0009] The purpose of the present invention is to address the deficiencies in the prior art. The present invention provides a standardized preparation method for recycled recycling materials, which realizes the continuous operation of cleaning and processing of waste plastics, and can efficiently remove the adhesion layer to obtain high-quality recycled waste plastics.

[0010] The above-mentioned object of the present invention is achieved by the following scheme: a standardized preparation method of recycled recycling materials, the method comprising the following steps:

[0011] S1, sandblasting and stripping the waste plastic, and then tearing and crushing the waste plastic to obtain waste plastic fragments;

[0012] S2, putting the waste plastic fragments into a vibrating screen for vibration separation;

[0013] S3, friction dehydration and cleaning of the waste plastic fragments separated by vibration;

[0014] S4, drying the waste plastic fragments and then homogenizing them;

[0015] S5, uniformly mixing the homogenized waste plastic fragments and antioxidant, and finally extruding and granulating them using an extruder.

[0016] In the above-mentioned standardized preparation method of recycled and recyclable materials, the waste plastic contains an adhesion layer, including at least one of waste drinking water barrels, household appliance casings, pipes, electroplated parts, and painted parts.

[0017] Preferably, the adhesive layer is at least one of a label, glue, paint and an electroplating layer.

[0018] In the above-mentioned standardized preparation method of recycled materials, the sandblasting stripping in step S1 is performed by a sandblasting stripping machine, and the sandblasting stripping machine comprises:

[0019] A rotating motor, wherein the output end of the rotating motor is connected to a fixing fixture, and the fixing fixture is used to fix the waste plastic, wherein the waste plastic is driven to rotate in a circumferential direction by the rotating motor;

[0020] A plurality of sandblasting moving tracks are arranged in a ring shape along the rotation direction of the waste plastics, and a sandblasting device is arranged on each sandblasting moving track, wherein the sandblasting port of each sandblasting device is aimed at the surface of the waste plastics, and the sandblasting device can reciprocate along the sandblasting moving track.

[0021] In the above-mentioned standardized preparation method of recycled materials, the sandblasting stripping time of the sandblasting stripping machine is 3-30s, and the abrasive of the sandblasting machine is at least one of steel sand, steel shot, wire cut shot, brown corundum, white corundum, black corundum, zirconium corundum, chrome corundum, green silicon carbide, black silicon carbide, corundum, glass sand, quartz sand, walnut sand and resin sand.

[0022] Preferably, the powder of the adhesion layer after sandblasting is separated by a solution density sedimentation method to obtain the abrasive.

[0023] The present invention uses a carefully designed three-sandblasting port layout, combined with a rotating motor and a mobile sandblasting port, to ensure that the abrasive can evenly and densely cover the surface of the waste plastic, achieve grinding without dead angles, effectively peel off various attachment layers, such as labels, glue, spray paint or electroplating layers, significantly improve the removal effect and quality, and adopt the physical impact principle for grinding, completely abandoning the traditional acid and alkali washing process, avoiding the use of chemical reagents, thereby reducing wastewater discharge and environmental pollution, reflecting a high degree of responsibility for environmental protection, and is a preferred solution under the sustainable development strategy. The present invention takes into account the density difference between the abrasive and the attachment layer (polymer material), and cleverly uses the density separation method to achieve effective recovery and reuse of the abrasive, which not only reduces production costs, but also reduces resource consumption, conforms to the development concept of low-carbon economy, and demonstrates the advantages of the circular economy model. However, the present invention uses mechanical automation technology to replace the inefficient manual grinding method, greatly improves the processing speed of the attachment layer on the surface of the waste plastic, realizes the possibility of batch operation, and meets the strict requirements of modern industry for efficiency and cost control.

[0024] In the above-mentioned standardized preparation method of recycled materials, the diameter of the waste plastic fragments after crushing in step S1 is 5-30 mm. The present invention utilizes a shredder and a crusher to perform shredding and crushing processing in sequence. After the shredder shreds the large plastic into blocks, it directly enters the crusher for further refinement, forming a continuous crushing operation line, which improves the fluency and efficiency of the overall processing flow. The shredder is used for coarse crushing first, and then the crusher is used for fine crushing. This two-stage crushing ensures that the size of the final crushed product is more uniform, which is convenient for subsequent sorting, cleaning and melting processes, and improves the quality of the recycled materials. Compared with a single crushing method, the shredding and crushing mode can reasonably allocate energy consumption while ensuring the crushing effect, avoiding energy waste caused by excessive crushing.

[0025] In the above-mentioned standardized preparation method of recycled materials, the vibrating screen includes filter screens distributed in an upper and lower manner, which are respectively a first filter screen and a second filter screen, and the middle of the first filter screen is provided with first mesh holes with a larger aperture, and the edge of the first filter screen is provided with second mesh holes with a smaller aperture, wherein the aperture of the mesh holes on the second filter screen is the same as the aperture of the second mesh holes, and the projection area of ​​the first filter screen in a horizontal plane is larger than the projection area of ​​the second filter screen in the same horizontal plane;

[0026] The edge of the second filter mesh plate is connected to the first filter mesh plate through a transition mesh plate, and the first mesh hole is located on the outside of the position where the transition mesh plate is connected to the first filter mesh plate, and the second mesh hole is located on the inside of the position where the transition mesh plate is connected to the first filter mesh plate, wherein the second mesh hole is arranged on the transition mesh plate.

[0027] In the above-mentioned standardized preparation method of recycled materials, the aperture of the second mesh is 1-30 mm, the aperture of the first mesh is 5-35 mm, and the aperture of the first mesh is larger than the second mesh.

[0028] In the process of crushing waste plastics, a certain amount of powdery impurities are often produced. If these powders are not removed in advance, they will dissolve or suspend in water in the subsequent wet friction cleaning process, increasing the turbidity and pollutant concentration of the water body. The present invention utilizes a special vibrating screen to not only optimize the size and shape of the waste plastic fragments, but also effectively remove the powdery impurities therein, creating favorable conditions for subsequent wet friction cleaning and other processes; the present invention can screen out waste plastic fragments of uniform size by controlling the screen specifications. This process ensures the consistency of the particle size of the final product, improves the overall quality and market acceptance of the recycled materials, and waste plastic fragments of uniform size are easier to be efficiently transported through transmission systems such as conveyor belts and pipelines, reducing the risk of blockage or jamming due to different sizes, and improving the fluency and efficiency of the entire recycling production line.

[0029] In the above-mentioned standardized preparation method of recycled materials, the rotation speed of friction dehydration cleaning in step S3 is completed by a friction cleaning machine, which has a spiral rotating shaft and a screen cylinder, wherein the rotation speed of the spiral rotating shaft is 1000-1500rpm, and the mesh aperture of the screen cylinder is 1-5mm.

[0030] The friction cleaning machine used in the present invention integrates a centrifugal separation design of a spiral rotating shaft and a screen drum, and its operating speed is set in the range of 1000 to 1500rpm. It is intended to efficiently remove foreign matter attached to the surface of waste plastics through the dual effects of centrifugal force and high-speed friction. The mesh aperture of the screen drum is finely adjusted between 1 and 5mm, which not only ensures effective interception of larger particles of foreign matter, but also allows smaller impurities and cleaned plastic fragments to pass smoothly, thereby achieving preliminary material classification and purification.

[0031] In the above-mentioned standardized preparation method of recycled materials, the homogenization treatment in step S4 is completed in a circulating stirring tank, wherein the temperature is 50-100° C. and the time is 0.5-5.0 hours. The present invention ensures the full removal of moisture in the material and the homogenization of the material components by controlling the homogenization temperature and time. This process not only eliminates the residual moisture in the material and prevents bubbles and quality defects that may occur during granulation, but also achieves full mixing of waste plastic fragments from different sources through long-term circulating stirring, thereby improving the stability and performance of the final product.

[0032] In the above-mentioned standardized preparation method of recycled materials, the extruder in step S5 is one of a single-screw extruder, a twin-screw extruder, a two-stage extruder, and a three-stage extruder.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. The present invention uses a sandblasting stripping machine to efficiently remove the labels, glue, paint, electroplating and other attachment layers on the surface of waste plastics, and then uses a shredder and a crusher to process the material into broken pieces with a diameter of 5-30mm, forming a continuous crushing operation to ensure uniform size. The sandblasting stripping machine adopts the principle of physical impact, avoids the use of chemical reagents, reduces environmental pollution, and reflects a high sense of responsibility for the environment. Through density differences, the solution density sedimentation method is used to achieve effective recovery and reuse of abrasives, reducing costs and resource consumption, which is in line with the concepts of circular economy and low-carbon economy.

[0035] 2. The present invention uses a specially made vibrating screen, including a first filter screen and a second filter screen, to size grade the broken pieces and remove powder, thereby optimizing the material size and reducing water pollution in subsequent cleaning processes. In addition, through a combination of shredding, crushing and vibrating screening, the uniformity and purity of the size of the recycled materials are ensured, thereby improving the applicability of subsequent processing and the market value of the recycled materials.

[0036] 3. The present invention utilizes a friction cleaning machine with a spiral rotating shaft and a screen cylinder to achieve deep cleaning and dehydration of foreign matter on the surface of waste plastics at a rotation speed of 1000-1500rpm. The screen aperture is designed to be 1-5mm to ensure effective separation of impurities.

[0037] 4. The present invention dries the washed broken pieces, and then performs a homogenization treatment at a temperature of 50-100° C. for 0.5-5.0 hours to improve the consistency and processing performance of the material. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1This is a schematic diagram of the sandblasting stripping machine of Example 1; 1. Sandblasting device; 2. Sandblasting port moving track; 3. Fixed fixture; 4. Rotating motor.

[0039] Figure 2 It is a schematic diagram of the working principle of the vibrating screen in Example 1.

[0040] Figure 3 This is a schematic diagram of the friction cleaning machine of Example 1; 1. spiral rotating shaft; 2. screen cylinder. DETAILED DESCRIPTION

[0041] The following are specific embodiments of the present invention, which further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0042] Embodiment 1:

[0043] S1. Recycling: According to Figure 1 As shown, the waste plastic drinking water barrel with attached labels is put into a sandblasting stripping machine for sandblasting stripping for 3 seconds, and the adhesive layer on the surface of the waste plastic product is stripped by the diamond abrasive of the sandblasting machine hitting the surface of the waste plastic product at high speed, thereby obtaining a clean waste plastic product with the attached layer removed, and an abrasive containing the attached layer powder;

[0044] The sandblasting stripping machine comprises:

[0045] A rotating motor, wherein the output end of the rotating motor is connected to a fixing fixture, and the fixing fixture is used to fix the waste plastic, wherein the waste plastic is driven to rotate in a circumferential direction by the rotating motor;

[0046] A plurality of sandblasting moving tracks are arranged in a ring shape along the rotation direction of the waste plastics, and a sandblasting device is arranged on each sandblasting moving track, wherein the sandblasting port of each sandblasting device is aimed at the surface of the waste plastics, and the sandblasting device can reciprocate along the sandblasting moving track.

[0047] S2, crushing treatment: the waste plastic parts after the attachment layer is peeled off are shredded by a shredder through a conveyor belt to obtain waste plastic blocks, and the waste plastic blocks are sent to a crusher with an inner screen mesh diameter of 5 mm through a conveyor belt to be crushed to obtain pure waste plastic shreds;

[0048] S3, dry vibration separation: according to Figure 2 As shown, the crushed waste plastic pieces are placed in a vibrating screen to perform vibration separation to remove powder from the waste plastic pieces;

[0049] The vibrating screen includes filter screen plates distributed in an upper and lower manner, which are respectively a first filter screen plate and a second filter screen plate, and a first mesh hole with a larger aperture is distributed in the middle of the first filter screen plate, and a second mesh hole with a smaller aperture is distributed at the edge of the first filter screen plate, wherein the aperture of the mesh hole on the second filter screen plate is the same as the aperture of the second mesh hole, and the projection area of ​​the first filter screen plate in a horizontal plane is larger than the projection area of ​​the second filter screen plate in the same horizontal plane;

[0050] The edge of the second filter mesh plate is connected to the first filter mesh plate through a transition mesh plate, and the first mesh hole is located on the outside of the position where the transition mesh plate is connected to the first filter mesh plate, and the second mesh hole is located on the inside of the position where the transition mesh plate is connected to the first filter mesh plate, wherein the second mesh hole is arranged on the transition mesh plate.

[0051] The aperture of the first mesh is larger than that of the second mesh, the aperture of the second mesh is 1 mm, and the aperture of the first mesh is 8 mm.

[0052] S4, wet friction cleaning: put the waste plastic fragments separated by vibration into Figure 3 The rotation speed shown is 1000 rpm, and the mesh size of the screen drum is 1 mm. The friction cleaning machine performs friction dehydration cleaning to further remove micron-sized impurities;

[0053] S5, drying and homogenization: the washed waste plastic fragments are blown with hot air to remove surface moisture, and blown into a circulating stirring tank for homogenization at 50°C for 0.5h;

[0054] S6 extrusion granulation: The homogenized waste plastic fragments and 0.3wt% antioxidant 1076 are mixed evenly, and melt-extruded and granulated at 250°C using a twin-screw extruder to obtain 100% recycled high-quality plastic particles.

[0055] Embodiment 2:

[0056] S1. Recycling: According to Figure 1 As shown, the waste plastic drinking water barrel with attached labels is put into a sandblasting stripping machine for sandblasting and stripping for 15 seconds, and the adhesive layer on the surface of the waste plastic product is stripped by the diamond abrasive of the sandblasting machine hitting the surface of the waste plastic product at high speed, thereby obtaining a clean waste plastic product with the attached layer removed, and an abrasive containing the attached layer powder;

[0057] The sandblasting stripping machine comprises:

[0058] A rotating motor, wherein the output end of the rotating motor is connected to a fixing fixture, and the fixing fixture is used to fix the waste plastic, wherein the waste plastic is driven to rotate in a circumferential direction by the rotating motor;

[0059] A plurality of sandblasting moving tracks are arranged in a ring shape along the rotation direction of the waste plastics, and a sandblasting device is arranged on each sandblasting moving track, wherein the sandblasting port of each sandblasting device is aimed at the surface of the waste plastics, and the sandblasting device can reciprocate along the sandblasting moving track.

[0060] S2, crushing treatment: the waste plastic parts after the attachment layer is peeled off are shredded by a shredder through a conveyor belt to obtain waste plastic blocks, and the waste plastic blocks are sent to a crusher with an inner screen mesh diameter of 15 mm through a conveyor belt to be crushed to obtain pure waste plastic fragments;

[0061] S3, dry vibration separation: according to Figure 2 As shown, the crushed waste plastic pieces are placed in a vibrating screen to perform vibration separation to remove powder from the waste plastic pieces;

[0062] The vibrating screen includes filter screen plates distributed in an upper and lower manner, which are respectively a first filter screen plate and a second filter screen plate, and a first mesh hole with a larger aperture is distributed in the middle of the first filter screen plate, and a second mesh hole with a smaller aperture is distributed at the edge of the first filter screen plate, wherein the aperture of the mesh hole on the second filter screen plate is the same as the aperture of the second mesh hole, and the projection area of ​​the first filter screen plate in a horizontal plane is larger than the projection area of ​​the second filter screen plate in the same horizontal plane;

[0063] The edge of the second filter mesh plate is connected to the first filter mesh plate through a transition mesh plate, and the first mesh hole is located on the outside of the position where the transition mesh plate is connected to the first filter mesh plate, and the second mesh hole is located on the inside of the position where the transition mesh plate is connected to the first filter mesh plate, wherein the second mesh hole is arranged on the transition mesh plate.

[0064] The aperture of the first mesh is larger than that of the second mesh, the aperture of the second mesh is 12 mm, and the aperture of the first mesh is 18 mm.

[0065] S4, wet friction cleaning: put the waste plastic fragments separated by vibration into Figure 3 The rotation speed shown is 1200 rpm, and the mesh size of the screen drum is 2 mm. The friction cleaning machine performs friction dehydration cleaning to further remove micron-sized impurities;

[0066] S5, drying and homogenization: the washed waste plastic fragments are blown with hot air to remove surface moisture, and then blown into a circulating stirring tank for homogenization at 80°C for 3 hours;

[0067] S6 extrusion granulation: The homogenized waste plastic fragments and 0.3wt% antioxidant 264 were mixed evenly, and melt-extruded and granulated at 245°C by a twin-screw extruder to obtain 100% recycled high-quality plastic particles.

[0068] Embodiment 3:

[0069] S1. Recycling: According to Figure 1 As shown, the waste plastic drinking water barrel with attached labels is put into a sandblasting stripping machine for sandblasting stripping for 30 seconds, and the adhesive layer on the surface of the waste plastic product is stripped by the diamond abrasive of the sandblasting machine hitting the surface of the waste plastic product at high speed, thereby obtaining a clean waste plastic product with the attached layer removed, and an abrasive containing the attached layer powder;

[0070] The sandblasting stripping machine comprises:

[0071] A rotating motor, wherein the output end of the rotating motor is connected to a fixing fixture, and the fixing fixture is used to fix the waste plastic, wherein the waste plastic is driven to rotate in a circumferential direction by the rotating motor;

[0072] A plurality of sandblasting moving tracks are arranged in a ring shape along the rotation direction of the waste plastics, and a sandblasting device is arranged on each sandblasting moving track, wherein the sandblasting port of each sandblasting device is aimed at the surface of the waste plastics, and the sandblasting device can reciprocate along the sandblasting moving track.

[0073] S2, crushing treatment: the waste plastic parts after the attachment layer is peeled off are shredded by a shredder through a conveyor belt to obtain waste plastic blocks, and the waste plastic blocks are sent to a crusher with an inner screen mesh diameter of 30 mm through a conveyor belt to be crushed to obtain pure waste plastic shreds;

[0074] S3, dry vibration separation: according to Figure 2 As shown, the crushed waste plastic pieces are placed in a vibrating screen to perform vibration separation to remove powder from the waste plastic pieces;

[0075] The vibrating screen includes filter screen plates distributed in an upper and lower manner, which are respectively a first filter screen plate and a second filter screen plate, and a first mesh hole with a larger aperture is distributed in the middle of the first filter screen plate, and a second mesh hole with a smaller aperture is distributed at the edge of the first filter screen plate, wherein the aperture of the mesh hole on the second filter screen plate is the same as the aperture of the second mesh hole, and the projection area of ​​the first filter screen plate in a horizontal plane is larger than the projection area of ​​the second filter screen plate in the same horizontal plane;

[0076] The edge of the second filter mesh plate is connected to the first filter mesh plate through a transition mesh plate, and the first mesh hole is located on the outside of the position where the transition mesh plate is connected to the first filter mesh plate, and the second mesh hole is located on the inside of the position where the transition mesh plate is connected to the first filter mesh plate, wherein the second mesh hole is arranged on the transition mesh plate.

[0077] The aperture of the first mesh is larger than that of the second mesh, the aperture of the second mesh is 25 mm, and the aperture of the first mesh is 35 mm.

[0078] S4, wet friction cleaning: put the waste plastic fragments separated by vibration into Figure 3The rotation speed shown is 1500 rpm, and the mesh size of the screen drum is 5 mm. The friction cleaning machine performs friction dehydration cleaning to further remove micron-sized impurities;

[0079] S5, drying and homogenization: the washed waste plastic fragments are blown with hot air to remove surface moisture, and then blown into a circulating stirring tank for homogenization at 100°C for 5 hours;

[0080] S6 extrusion granulation: The homogenized waste plastic fragments and 0.3wt% antioxidant 1076 are mixed evenly, and melt-extruded and granulated at 260°C using a twin-screw extruder to obtain 100% recycled high-quality plastic particles.

[0081] Embodiment 4:

[0082] S1. Recycling: Put the ABS pipe with attached labels into a sandblasting stripping machine and perform sandblasting stripping for 5 seconds. The diamond abrasive of the sandblasting machine will impact the surface of the waste plastic parts at high speed to strip the attached layer on the surface, and obtain a clean waste plastic part with the attached layer removed, and an abrasive containing the attached layer powder;

[0083] The sandblasting stripping machine comprises:

[0084] A rotating motor, wherein the output end of the rotating motor is connected to a fixing fixture, and the fixing fixture is used to fix the waste plastic, wherein the waste plastic is driven to rotate in a circumferential direction by the rotating motor;

[0085] A plurality of sandblasting moving tracks are arranged in a ring shape along the rotation direction of the waste plastics, and a sandblasting device is arranged on each sandblasting moving track, wherein the sandblasting port of each sandblasting device is aimed at the surface of the waste plastics, and the sandblasting device can reciprocate along the sandblasting moving track.

[0086] S2, crushing treatment: the waste plastic parts after the attachment layer is peeled off are shredded by a shredder through a conveyor belt to obtain waste plastic blocks, and the waste plastic blocks are sent to a crusher with an inner screen mesh diameter of 13 mm through a conveyor belt to be crushed to obtain pure waste plastic fragments;

[0087] S3, dry vibration separation: according to Figure 2 As shown, the crushed waste plastic pieces are placed in a vibrating screen to perform vibration separation to remove powder from the waste plastic pieces;

[0088] The vibrating screen includes filter screen plates distributed in an upper and lower manner, which are respectively a first filter screen plate and a second filter screen plate, and a first mesh hole with a larger aperture is distributed in the middle of the first filter screen plate, and a second mesh hole with a smaller aperture is distributed at the edge of the first filter screen plate, wherein the aperture of the mesh hole on the second filter screen plate is the same as the aperture of the second mesh hole, and the projection area of ​​the first filter screen plate in a horizontal plane is larger than the projection area of ​​the second filter screen plate in the same horizontal plane;

[0089] The edge of the second filter mesh plate is connected to the first filter mesh plate through a transition mesh plate, and the first mesh hole is located on the outside of the position where the transition mesh plate is connected to the first filter mesh plate, and the second mesh hole is located on the inside of the position where the transition mesh plate is connected to the first filter mesh plate, wherein the second mesh hole is arranged on the transition mesh plate.

[0090] The aperture of the first mesh is larger than that of the second mesh, the aperture of the second mesh is 5 mm, and the aperture of the first mesh is 16 mm.

[0091] S4, wet friction cleaning: put the waste plastic fragments separated by vibration into Figure 3 The rotation speed shown is 1500 rpm, and the mesh size of the screen drum is 1 mm. The friction cleaning machine performs friction dehydration cleaning to further remove micron-sized impurities;

[0092] S5, drying and homogenization: the washed waste plastic fragments are blown with hot air to remove surface moisture, and blown into a circulating stirring tank for homogenization at 70°C for 2h;

[0093] S6 extrusion granulation: The homogenized waste plastic fragments and 0.3% antioxidant 225 are mixed evenly, and melt-extruded and granulated at 180°C using a twin-screw extruder to obtain 100% recycled high-quality plastic particles.

[0094] Embodiment 5:

[0095] S1. Recycling: Put the ABS TV housing with attached labels into a sandblasting stripping machine and sandblast for 5 seconds. The diamond abrasive of the sandblasting machine hits the surface of the waste plastic parts at high speed to strip the attached layer on the surface, thereby obtaining a clean waste plastic part without the attached layer, and an abrasive containing the attached layer powder;

[0096] The sandblasting stripping machine comprises:

[0097] A rotating motor, wherein the output end of the rotating motor is connected to a fixing fixture, and the fixing fixture is used to fix the waste plastic, wherein the waste plastic is driven to rotate in a circumferential direction by the rotating motor;

[0098] A plurality of sandblasting moving tracks are arranged in a ring shape along the rotation direction of the waste plastics, and a sandblasting device is arranged on each sandblasting moving track, wherein the sandblasting port of each sandblasting device is aimed at the surface of the waste plastics, and the sandblasting device can reciprocate along the sandblasting moving track.

[0099] S2, crushing treatment: the waste plastic parts after the attachment layer is peeled off are shredded by a shredder through a conveyor belt to obtain waste plastic blocks, and the waste plastic blocks are sent to a crusher with an inner screen mesh diameter of 13 mm through a conveyor belt to be crushed to obtain pure waste plastic fragments;

[0100] S3, dry vibration separation: according to Figure 2 As shown, the crushed waste plastic pieces are placed in a vibrating screen to perform vibration separation to remove powder from the waste plastic pieces;

[0101] The vibrating screen includes filter screen plates distributed in an upper and lower manner, which are respectively a first filter screen plate and a second filter screen plate, and a first mesh hole with a larger aperture is distributed in the middle of the first filter screen plate, and a second mesh hole with a smaller aperture is distributed at the edge of the first filter screen plate, wherein the aperture of the mesh hole on the second filter screen plate is the same as the aperture of the second mesh hole, and the projection area of ​​the first filter screen plate in a horizontal plane is larger than the projection area of ​​the second filter screen plate in the same horizontal plane;

[0102] The edge of the second filter mesh plate is connected to the first filter mesh plate through a transition mesh plate, and the first mesh hole is located on the outside of the position where the transition mesh plate is connected to the first filter mesh plate, and the second mesh hole is located on the inside of the position where the transition mesh plate is connected to the first filter mesh plate, wherein the second mesh hole is arranged on the transition mesh plate.

[0103] The aperture of the first mesh is larger than that of the second mesh, the aperture of the second mesh is 5 mm, and the aperture of the first mesh is 16 mm.

[0104] S4, wet friction cleaning: put the waste plastic fragments separated by vibration into Figure 3 The rotation speed shown is 1500 rpm, and the mesh size of the screen drum is 1 mm. The friction cleaning machine performs friction dehydration cleaning to further remove micron-sized impurities;

[0105] S5, drying and homogenization: the washed waste plastic fragments are blown with hot air to remove surface moisture, and blown into a circulating stirring tank for homogenization at 70°C for 2h;

[0106] S6 extrusion granulation: The homogenized waste plastic fragments and 0.3% antioxidant 225 are mixed evenly, and melt-extruded and granulated at 200°C by a twin-screw extruder to obtain 100% recycled high-quality plastic particles.

[0107] Embodiment 6:

[0108] S1. Recycling: Put the ABS electroplated parts containing the electroplated layer into a sandblasting stripping machine and sandblast for 5 seconds. The diamond abrasive of the sandblasting machine hits the surface of the waste plastic parts at high speed to strip the adhesion layer on the surface, and obtain a clean waste plastic part without the adhesion layer, and an abrasive containing the adhesion layer powder;

[0109] The sandblasting stripping machine comprises:

[0110] A rotating motor, wherein the output end of the rotating motor is connected to a fixing fixture, and the fixing fixture is used to fix the waste plastic, wherein the waste plastic is driven to rotate in a circumferential direction by the rotating motor;

[0111] A plurality of sandblasting moving tracks are arranged in a ring shape along the rotation direction of the waste plastics, and a sandblasting device is arranged on each sandblasting moving track, wherein the sandblasting port of each sandblasting device is aimed at the surface of the waste plastics, and the sandblasting device can reciprocate along the sandblasting moving track.

[0112] S2, crushing treatment: the waste plastic parts after the attachment layer is peeled off are shredded by a shredder through a conveyor belt to obtain waste plastic blocks, and the waste plastic blocks are sent to a crusher with an inner screen mesh diameter of 13 mm through a conveyor belt to be crushed to obtain pure waste plastic fragments;

[0113] S3, dry vibration separation: according to Figure 2 As shown, the crushed waste plastic pieces are placed in a vibrating screen to perform vibration separation to remove powder from the waste plastic pieces;

[0114] The vibrating screen includes filter screen plates distributed in an upper and lower manner, which are respectively a first filter screen plate and a second filter screen plate, and a first mesh hole with a larger aperture is distributed in the middle of the first filter screen plate, and a second mesh hole with a smaller aperture is distributed at the edge of the first filter screen plate, wherein the aperture of the mesh hole on the second filter screen plate is the same as the aperture of the second mesh hole, and the projection area of ​​the first filter screen plate in a horizontal plane is larger than the projection area of ​​the second filter screen plate in the same horizontal plane;

[0115] The edge of the second filter mesh plate is connected to the first filter mesh plate through a transition mesh plate, and the first mesh hole is located on the outside of the position where the transition mesh plate is connected to the first filter mesh plate, and the second mesh hole is located on the inside of the position where the transition mesh plate is connected to the first filter mesh plate, wherein the second mesh hole is arranged on the transition mesh plate.

[0116] The aperture of the first mesh is larger than that of the second mesh, the aperture of the second mesh is 5 mm, and the aperture of the first mesh is 16 mm.

[0117] S4, wet friction cleaning: put the waste plastic fragments separated by vibration into Figure 3 The rotation speed shown is 1500 rpm, and the mesh size of the screen drum is 1 mm. The friction cleaning machine performs friction dehydration cleaning to further remove micron-sized impurities;

[0118] S5, drying and homogenization: the washed waste plastic fragments are blown with hot air to remove surface moisture, and blown into a circulating stirring tank for homogenization at 70°C for 2h;

[0119] S6 extrusion granulation: The homogenized waste plastic fragments and 0.3% antioxidant 225 are mixed evenly, and melt-extruded and granulated at 210°C using a twin-screw extruder to obtain 100% recycled high-quality plastic particles.

[0120] Comparative Example 1:

[0121] The only difference from Example 1 is that no sandblasting was performed.

[0122] Comparative Example 2:

[0123] The only difference from Example 1 is that no shredding or crushing is performed.

[0124] Comparative Example 3:

[0125] The only difference from Example 1 is that vibration separation is not performed.

[0126] Comparative Example 4:

[0127] The only difference from Example 1 is that no friction dehydration cleaning is performed.

[0128] Comparative Example 5:

[0129] The only difference from Example 1 is that no homogenization treatment is performed.

[0130] Table 1: Performance test results of recycled materials prepared in Examples 1-6 and Comparative Examples 1-5

[0131]

[0132]

[0133] In summary, the present invention uses a sandblasting process to remove labels, glue, paint, electroplating and other attachments on the surface of waste plastics, and further improves the recycling quality through processes such as shredding and crushing, vibrating screens and friction cleaning. It can not only achieve efficient and environmentally friendly removal of attachments on the surface of waste plastics, but also achieve standardized, continuous and automated preparation of recycled materials. In addition, a large number of dry treatment processes greatly reduce water use and pollution, and very well achieve environmentally friendly, efficient and standard waste plastic recycling.

[0134] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0135] Although the present invention has been described in detail and some specific embodiments have been cited, it is obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention.

Claims

1. A standardized preparation method for recycled materials, characterized in that: The method comprises the following steps: S1, sandblasting and stripping the waste plastic, and then tearing and crushing the waste plastic to obtain waste plastic fragments; S2, putting the waste plastic fragments into a vibrating screen for vibration separation; S3, friction dehydration and cleaning of the waste plastic fragments separated by vibration; S4, drying the waste plastic fragments and then homogenizing them; S5, uniformly mixing the homogenized waste plastic fragments and antioxidant, and finally extruding and granulating them using an extruder.

2. A standardized preparation method for recycled materials according to claim 1, characterized in that: The waste plastic contains an adhesion layer, including at least one of waste drinking water barrels, household appliance shells, pipes, electroplated parts, and painted parts.

3. A standardized preparation method for recycled materials according to claim 1, characterized in that: The sandblasting stripping in step S1 is performed by using a sandblasting stripping machine, and the sandblasting stripping machine comprises: A rotating motor, wherein the output end of the rotating motor is connected to a fixing fixture, and the fixing fixture is used to fix the waste plastic, wherein the waste plastic is driven to rotate in a circumferential direction by the rotating motor; A plurality of sandblasting moving tracks are arranged in a ring shape along the rotation direction of the waste plastics, and a sandblasting device is arranged on each sandblasting moving track, wherein the sandblasting port of each sandblasting device is aimed at the surface of the waste plastics, and the sandblasting device can reciprocate along the sandblasting moving track.

4. A standardized preparation method for recycled materials according to claim 3, characterized in that: The sandblasting stripping time of the sandblasting stripping machine is 3-30s, and the abrasive of the sandblasting machine is at least one of steel sand, steel shot, wire cut shot, brown corundum, white corundum, black corundum, zirconium corundum, chrome corundum, green silicon carbide, black silicon carbide, corundum, glass sand, quartz sand, walnut sand and resin sand.

5. The standardized preparation method of recycled materials according to claim 1, characterized in that: The diameter of the waste plastic fragments after crushing in step S1 is 5-30 mm.

6. A standardized preparation method for recycled materials according to claim 1, characterized in that: The vibrating screen includes filter screen plates distributed in an upper and lower manner, which are respectively a first filter screen plate and a second filter screen plate, and a first mesh hole with a larger aperture is distributed in the middle of the first filter screen plate, and a second mesh hole with a smaller aperture is distributed at the edge of the first filter screen plate, wherein the aperture of the mesh hole on the second filter screen plate is the same as the aperture of the second mesh hole, and the projection area of ​​the first filter screen plate in a horizontal plane is larger than the projection area of ​​the second filter screen plate in the same horizontal plane; The edge of the second filter mesh plate is connected to the first filter mesh plate through a transition mesh plate, and the first mesh hole is located on the outside of the position where the transition mesh plate is connected to the first filter mesh plate, and the second mesh hole is located on the inside of the position where the transition mesh plate is connected to the first filter mesh plate, wherein the second mesh hole is arranged on the transition mesh plate.

7. A standardized preparation method for recycled materials according to claim 6, characterized in that: The aperture of the second mesh is 1-30 mm, the aperture of the first mesh is 5-35 mm, and the aperture of the first mesh is larger than that of the second mesh.

8. The standardized preparation method of recycled materials according to claim 1, characterized in that: The rotation speed of the friction dehydration cleaning in step S3 is completed by using a friction cleaning machine, which has a spiral rotating shaft and a screen cylinder, wherein the rotation speed of the spiral rotating shaft is 1000-1500rpm, and the mesh aperture of the screen cylinder is 1-5mm.

9. The standardized preparation method of recycled materials according to claim 1, characterized in that: The homogenization treatment in step S4 is completed in a circulating stirring tank, wherein the temperature is 50-100° C. and the time is 0.5-5.0 h.

10. The standardized preparation method of recycled materials according to claim 1, characterized in that: In step S5, the extruder is one of a single-screw extruder, a twin-screw extruder, a two-stage extruder, and a three-stage extruder.

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