Melting, homogenizing and regenerating processing system for clean bottle flakes

Abstract

An outlet of a screw feeding hopper is connected with an inlet of a forced feeding machine, an outlet of the forced feeding machine is connected with a feeding port of a double-screw extruder, a bottle-cleaning-piece articulated chute is connected with an inlet of a fluidized bed, an outlet of the fluidized bed is connected with an air conveying pipeline through a rotary feeding valve, and the air conveying pipeline is connected with an air outlet of the double-screw extruder. An outlet of the air conveying pipeline is connected with an inlet of the drying tower, and the fluidized bed and the drying tower are internally and respectively provided with a hot air drying circulating system for drying the clean bottle flakes; an outlet of the drying tower is connected with an inlet of the bottle chip surge bin through an inlet stop valve, and an outlet of the bottle chip surge bin is connected with an inlet of the screw feeding hopper through an outlet stop valve; and the bottle flake buffer bin and the screw feeding hopper are respectively connected with a suction port of the feeding vacuum unit through a corresponding vacuum separator. According to the melting, homogenizing and regenerating processing system for the clean bottle flakes, the water content of the clean bottle flakes can be reduced, degradation after melt extrusion is reduced, the product quality is improved, and finally, the melt can be directly sliced or spun.

Description

Technical Field

[0001] The utility model relates to a polyester production system, in particular to a bottle cleaning flake melting homogenization regeneration processing system, belonging to the technical field of polyester production equipment. Background Art

[0002] Polyester materials are used in large quantities in the production of packaging containers for beverages, foods, etc., especially beverage bottles and mineral water bottles, which are increasing year by year. Used beverage bottles and mineral water bottles will cause a large amount of waste plastics, and the natural degradation of plastics is very slow. Recycling and reusing waste polyester materials can not only effectively avoid environmental pollution, but also avoid the waste of resources. It is a good way to solve the pollution of waste plastics, which is of great significance to protecting the environment and alleviating the world's resource crisis. Usually, waste polyester materials are sorted, crushed, cleaned, and dehydrated to obtain clean bottle flakes, and then the clean bottle flakes are melted in a twin-screw extruder at normal pressure and temperature, and then directly pelletized after pressurization and filtration.

[0003] The Chinese invention patent application with publication number CN 111235649A discloses a process for spinning regenerated polyester filaments using recycled polyester bottle flakes, which includes the following steps: cleaning, mixing, pretreatment, melting, primary filtration, homogenization and viscosity enhancement, fine filtration, spinning, cooling and forming, bundling and oiling, stretching and shaping, winding and packaging.

[0004] The technical solution and the prior art have the following deficiencies: 1. The clean bottle flakes are not dried and dehydrated before entering the twin-screw extruder, but are only dehydrated by the vacuum system after the twin-screw extruder, which requires high air extraction capacity of the vacuum system, and the high water content affects the production capacity of the twin-screw extruder and the B value, viscosity and spinnability of the final product;

[0005] 2. The melt outlet temperature of the twin-screw extruder is unstable. When the melt temperature is too high, it will cause melt degradation;

[0006] 3. The melt at the outlet of the twin-screw extruder is directly pelletized, and the quality of the slices is poor. Utility Model Content

[0007] The purpose of this section is to summarize some aspects of the embodiments of the utility model and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract of the specification and the name of the utility model of this application to avoid ambiguity in the abstract of the specification or the utility model, and such simplifications or omissions cannot be used to limit the scope of the utility model.

[0008] In view of the above problems and / or the problems existing in the prior art, the present utility model is proposed.

[0009] The purpose of the utility model is to overcome the problems existing in the prior art and provide a bottle cleaning flake melting homogenization regeneration processing system, which can reduce the water content of the bottle cleaning flakes, reduce the degradation of the melt after extrusion, and improve the product quality.

[0010] In order to solve the above technical problems, the utility model provides a bottle-cleaning flake melting homogenization regeneration processing system, comprising a screw feed hopper, the outlet of the screw feed hopper is connected to the inlet of a forced feeder, the outlet of the forced feeder is connected to the feed port of a twin-screw extruder, the bottle-cleaning flake chute is connected to the inlet of a fluidized bed, the outlet of the fluidized bed is connected to an air delivery duct through a rotary feeding valve, the outlet of the air delivery duct is connected to the inlet of a drying tower, and the fluidized bed and the drying tower are respectively provided with a hot air drying circulation system for drying the bottle-cleaning flakes;

[0011] The outlet of the drying tower is connected to the inlet of the bottle flake buffer bin through an inlet cut-off valve, and the outlet of the bottle flake buffer bin is connected to the inlet of the screw feed hopper through an outlet cut-off valve; the bottle flake buffer bin and the screw feed hopper are respectively connected to the suction port of the feeding vacuum unit through corresponding vacuum separators.

[0012] As an improvement of the utility model, a buffer bin material level meter is provided on the side wall of the bottle flake buffer bin, and the buffer bin material level meter is interlocked with the inlet cut-off valve.

[0013] As a further improvement of the utility model, a screw feed hopper level meter is provided on the side wall of the screw feed hopper, and the screw feed hopper level meter is interlocked with the outlet shut-off valve.

[0014] As a further improvement of the utility model, the top gas phase outlet of the twin-screw extruder is connected to the inlet of the vacuum buffer tank, and the exhaust port of the vacuum buffer tank is connected to the suction port of the screw vacuum unit through a corresponding vacuum separator.

[0015] As a further improvement of the utility model, the melt outlet of the twin-screw extruder is connected to the inlet of the booster pump, the outlet of the booster pump is connected to the feed port of the melt cooler through a melt pre-filter, the discharge port of the melt cooler is connected to the inlet of the homogenization reactor, the outlet of the homogenization reactor is connected to the inlet of the melt filter through a melt pump, and the outlet of the melt filter is connected to a pelletizing device and / or a spinning device.

[0016] As a further improvement of the utility model, the heat medium outlet of the melt cooler is connected to the inlet of the fin heat exchanger, the outlet of the fin heat exchanger is connected to the inlet of the heat medium circulation pump, and the outlet of the heat medium circulation pump is connected to the heat medium inlet of the melt cooler.

[0017] As a further improvement of the present invention, the top gas phase outlet of the homogenization reactor is connected to the inlet of the condenser, and the outlet of the condenser is connected to the suction port of the homogenization vacuum unit through a corresponding vacuum separator.

[0018] Compared with the prior art, the utility model has achieved the following beneficial effects: 1. The bottle cleaning flakes are fully dried and dehydrated by a fluidized bed and a drying tower before the twin-screw extruder, and a feeding vacuum system is provided to reduce the water content of the bottle cleaning flakes. The bottle cleaning flakes enter the twin-screw extruder under a vacuum state, and while isolating the air, the moisture on the surface of the bottle cleaning flakes is effectively removed. The quality of the melt can be ensured due to low oxygen and low moisture during the screw melting stage.

[0019] 2. It can reduce the vacuum capacity of the twin-screw extruder vacuum system, and select a vacuum unit with smaller power, which can reduce investment and operating energy consumption, while increasing the production capacity of the twin-screw extruder and ensuring the B value, viscosity and spinnability of the melt.

[0020] 3. A melt cooler is set at the outlet of the twin-screw extruder to cool and control the melt by controlling the temperature of the circulating heat medium, stabilize the melt temperature after the twin-screw extruder, and avoid excessive melt temperature. After cooling and temperature control, the melt can effectively reduce the degradation of the melt and the possibility of product deterioration. It also adjusts the temperature before entering the kettle, which is conducive to the realization of the subsequent melt homogenization function.

[0021] 4. A homogenizing reactor and a homogenizing vacuum unit are set after the twin-screw extruder to improve product quality after homogenizing the melt. It can be directly pelletized, reducing the energy consumption of bottle flake recycling and carbon emissions, and can also be spun. It not only meets the production requirements of clean bottle flakes to food-grade basic slices, but also meets the requirements of high spinning fineness and full roll rate, realizing the whole process from clean bottle flake drying to screw melting to melt homogenization, pelletizing or spinning. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. The drawings are only provided for reference and explanation, not for limiting the present utility model. Among them:

[0023] Figure 1 This is a flow chart of the bottle cleaning flake melting homogenization regeneration processing system of the utility model;

[0024] In the figure: 1. fluidized bed; 2. rotary feed valve; 3. air filter; 4. Roots blower; 5. air delivery tee; 6. drying tower; 7. bottle flake buffer bin; 8. vacuum separator one; 9. screw feed hopper; 10. vacuum separator two; 11. feeding vacuum unit; 12. forced feeder; 13. twin-screw extruder; 14. vacuum buffer tank; 15. vacuum separator three; 16. screw vacuum unit; 17. booster pump; 18. melt primary filter; 19. melt cooler; 20. heat medium circulation pump; 21. fin heat exchanger; 22. homogenization reactor; 23. melt pump; 24. melt filter; 25. condenser; 26. vacuum separator four; 27. homogenization vacuum unit; 28. pelletizing equipment; 29. ​​spinning equipment. DETAILED DESCRIPTION

[0025] In the following description of the utility model, the terms "upper", "lower", "front", "back", "left", "right", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the utility model and simplifying the description, and do not mean that the device must have a specific direction.

[0026] In order to make the technical means, creative features, objectives and effects of the present invention easier to understand, the present invention is further described below with reference to specific figures. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0028] like Figure 1 As shown, the clean bottle flakes melting homogenization regeneration processing system of the utility model comprises a fluidized bed 1, a drying tower 6, a bottle flakes buffer bin 7, a forced feeder 12 and a twin-screw extruder 13, the clean bottle flakes chute is connected to the inlet of the fluidized bed 1, a hot air drying circulation system for drying the clean bottle flakes is provided in the fluidized bed 1, the outlet of the fluidized bed 1 is connected to the feed port of the air delivery tee 5 through a rotary feeding valve 2, the main inlet of the air delivery tee 5 is connected to the outlet of the Roots blower 4, the inlet of the Roots blower 4 is provided with an air filter 3, the outlet of the air delivery tee 5 is connected to the inlet of the drying tower 6 through an air delivery pipeline, the outlet of the drying tower 6 is connected to the inlet of the bottle flakes buffer bin 7 through an inlet cut-off valve, and the outlet of the bottle flakes buffer bin 7 is connected to the inlet of the screw feed hopper 9 through an outlet cut-off valve.

[0029] The bottle flake buffer bin 7 is connected to the suction port of the feeding vacuum unit 11 through a vacuum separator 1 8 , and the screw feeding hopper 9 is connected to the suction port of the feeding vacuum unit 11 through a vacuum separator 2 10 .

[0030] The top gas phase outlet of the twin-screw extruder 13 is connected to the inlet of the vacuum buffer tank 14 , and the exhaust port of the vacuum buffer tank 14 is connected to the suction port of the screw vacuum unit 16 through the vacuum separator 3 15 .

[0031] The outlet of the screw feed hopper 9 is connected to the inlet of the forced feeder 12, and the outlet of the forced feeder 12 is connected to the feed port of the twin-screw extruder 13. The melt outlet of the twin-screw extruder 13 is connected to the inlet of the booster pump 17, and the outlet of the booster pump 17 is connected to the inlet of the melt pre-filter 18. Two groups of melt pre-filters 18 are provided in parallel, and the outlets of the two melt pre-filters 18 are connected to the feed port of the melt cooler 19. The heat medium outlet of the melt cooler 19 is connected to the inlet of the fin heat exchanger 21, and the outlet of the fin heat exchanger 21 is connected to the inlet of the heat medium circulation pump 20, and the outlet of the heat medium circulation pump 20 is connected to the heat medium inlet of the melt cooler 19.

[0032] The discharge port of the melt cooler 19 is connected to the inlet of the homogenizing reactor 22, the gas phase outlet at the top of the homogenizing reactor 22 is connected to the inlet of the condenser 25, and the outlet of the condenser 25 is connected to the suction port of the homogenizing vacuum unit 27 through the vacuum separator 26. The outlet of the homogenizing reactor 22 is connected to the inlet of the melt filter 24 through the melt pump 23, and two groups of melt filters 24 are provided in parallel, and the outlets of the two melt filters 24 are connected to the pelletizing device 28, or connected to the spinning device 29, or connected to the pelletizing device 28 and the spinning device 29 at the same time.

[0033] The clean bottle flakes after screening are quantitatively fed into the fluidized bed 1, and the fluidized bed 1 is provided with a hot air drying circulation system, which removes the surface moisture of the clean bottle flakes, improves the crystallinity, and prevents the clean bottle flakes from sticking and agglomerating. The rotary feeding valve 2 provided at the outlet of the fluidized bed 1 realizes the air shut-off function while feeding; the preliminary dried clean bottle flakes discharged by the rotary feeding valve 2 enter the drying tower 6 under air flow transportation, and the drying tower 6 is provided with a hot air drying circulation system to further remove moisture.

[0034] After being dried again, the clean bottle flakes enter the bottle flake buffer bin 7 through the inlet cut-off valve for buffering, and then enter the screw feed hopper 9 through the outlet cut-off valve. The material level of the bottle flake buffer bin 7 is interlocked with the inlet cut-off valve, and the outlet cut-off valve is interlocked with the material level of the screw feed hopper 9. The bottle flake buffer bin 7 and the screw feed hopper 9 are equipped with an independent vacuum unit to further extract the moisture and air in the clean bottle flakes.

[0035] The dried clean bottle flakes in the screw feed hopper 9 are fed into the twin-screw extruder 13 through the forced feeder 12 for melting. Most of the low-component substances such as water, oil, short-chain polymers, PVC and polyolefin degradation products generated during the melting process enter the vacuum buffer tank 14 through the vacuum exhaust port for buffering, and are then removed by the vacuum separator 15 and extracted by the screw vacuum unit 16. The vacuum pressure is controlled by the screw vacuum unit 16.

[0036] The outlet melt of the twin-screw extruder 13 is pressurized by the booster pump 17 and then enters the melt primary filter 18 for filtration. After filtering out the metal, PVC and polyolefin carbides and other impurities in the clean bottle slices, the quality of the recycled polyester low-viscosity slices is improved. The clean melt enters the melt cooler 19 for cooling. The melt cooler 19 is equipped with a heat medium circulation pump 20 and a fin heat exchanger 21 to cool the melt by low-temperature heat transfer oil.

[0037] The cooled melt enters the horizontal homogenization reactor 22 for homogenization and viscosity increase, and is then pressurized by the melt pump 23 and filtered by the melt filter 24 before being fed to the pelletizing device 28 or the spinning device 29. The by-products produced by the homogenization reaction are condensed by the condenser 25 and separated by the vacuum separator 26 before being removed, and the vacuum pressure of the reactor is controlled by the homogenization vacuum unit 27.

[0038] The above description is only the preferred feasible embodiment of the utility model, which shows and describes the basic principle, main features and advantages of the utility model, but does not limit the scope of patent protection of the utility model. The technicians in this industry should understand that the utility model is not limited by the above embodiments. In addition to the above embodiments, the utility model can also have other implementation modes without departing from the spirit and scope of the utility model. The utility model will also have various changes and improvements. All technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the utility model. The scope of protection required by the utility model is defined by the attached claims and their equivalents. The technical features not described in the utility model can be achieved by or using existing technologies, which will not be repeated here.

Claims

1. A system for melting and homogenizing bottle clean flakes for regeneration, comprising a screw feed hopper, the outlet of which is connected to the inlet of a forced feeder, the outlet of which is connected to the feed port of a twin-screw extruder, characterized in that: The bottle cleaning flakes slide pipe is connected to the inlet of the fluidized bed, the outlet of the fluidized bed is connected to the air delivery pipe through a rotary feeding valve, the outlet of the air delivery pipe is connected to the inlet of the drying tower, and the fluidized bed and the drying tower are respectively provided with a hot air drying circulation system for drying the bottle cleaning flakes; The outlet of the drying tower is connected to the inlet of the bottle flake buffer bin through an inlet cut-off valve, and the outlet of the bottle flake buffer bin is connected to the inlet of the screw feed hopper through an outlet cut-off valve; the bottle flake buffer bin and the screw feed hopper are respectively connected to the suction port of the feeding vacuum unit through corresponding vacuum separators.

2. The bottle cleaning flakes melting homogenization regeneration processing system according to claim 1 is characterized by: A buffer bin material level meter is provided on the side wall of the bottle flake buffer bin, and the buffer bin material level meter is interlocked with the inlet cut-off valve.

3. The bottle cleaning flakes melting homogenization regeneration processing system according to claim 1, characterized in that: A screw feed hopper material level meter is provided on the side wall of the screw feed hopper, and the screw feed hopper material level meter is interlocked with the outlet cut-off valve.

4. The bottle cleaning flakes melting homogenization regeneration processing system according to claim 1, characterized in that: The top gas phase outlet of the twin-screw extruder is connected to the inlet of the vacuum buffer tank, and the exhaust port of the vacuum buffer tank is connected to the suction port of the screw vacuum unit through a corresponding vacuum separator.

5. The bottle cleaning flakes melting homogenization regeneration processing system according to claim 1, characterized in that: The melt outlet of the twin-screw extruder is connected to the inlet of a booster pump, the outlet of the booster pump is connected to the feed port of a melt cooler through a melt pre-filter, the discharge port of the melt cooler is connected to the inlet of a homogenizing reactor, the outlet of the homogenizing reactor is connected to the inlet of a melt filter through a melt pump, and the outlet of the melt filter is connected to a pelletizing device and / or a spinning device.

6. The bottle cleaning flakes melting homogenization regeneration processing system according to claim 5, characterized in that: The heat medium outlet of the melt cooler is connected to the inlet of the fin heat exchanger, the outlet of the fin heat exchanger is connected to the inlet of the heat medium circulation pump, and the outlet of the heat medium circulation pump is connected to the heat medium inlet of the melt cooler.

7. The bottle cleaning flakes melting homogenization regeneration processing system according to claim 5, characterized in that: The top gas phase outlet of the homogenization reactor is connected to the inlet of the condenser, and the outlet of the condenser is connected to the suction port of the homogenization vacuum unit through a corresponding vacuum separator.

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