Safe and environment-friendly waste plastic degradation system

Abstract

The utility model provides a safe and environment-friendly waste plastic degradation system which is characterized in that a reaction device is arranged on an integrated stirring and heating device, a temperature measuring device is arranged in the reaction device, a first inlet of the reaction device is communicated with an outlet of a nitrogen device, and a second inlet of the reaction device is connected with a condensing device; a third inlet of the reaction device is used for introducing reaction raw materials, an outlet of the reaction device is communicated with an inlet of the suction filtration device, and an outlet of the suction filtration device is communicated with an inlet of the degradation product collecting device. According to the reaction device, the problems of difficulty in temperature control and low stirring efficiency of the existing reaction system are solved, the whole degradation reaction is complete in one-time reaction in the reaction device, the product quality is controllable, ethylene glycol in reaction byproducts is recovered, and the problem that the byproducts are difficult to recover in the traditional reaction device is solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of modified asphalt test sample preparation, in particular to a safe and environmentally friendly waste plastic degradation system. Background Art

[0002] With the substantial increase in the use of plastic products, waste plastic PET has accumulated in large quantities. Plastic itself is not a pollutant, but plastic waste leaks into the natural environment such as soil and water and is difficult to degrade, which will cause visual pollution, soil damage, microplastics and other environmental hazards. Therefore, how to recycle and reuse PET has become a key issue for sustainable development.

[0003] In the PET alcoholysis process, the commonly used PET alcoholysis devices currently mostly use traditional heating, stirring devices, step-by-step reactions, etc., which have the following problems:

[0004] (1) Traditional devices do not have sensitive temperature control devices and cannot measure temperature in a timely and accurate manner. Temperature control is not accurate enough, which affects the reaction rate and product quality.

[0005] (2) The stirring efficiency of the stirring equipment is low, making it difficult to stir evenly so that the raw materials can fully contact and react;

[0006] (3) The operation of traditional devices is relatively complicated, and the reaction is carried out in batches. The step-by-step reaction will reduce efficiency and yield, and it is difficult to control the product quality during the process;

[0007] (4) The by-products produced during the experimental process of traditional devices cannot be recycled, resulting in negative factors such as by-product accumulation, environmental pollution, and waste of resources.

[0008] Therefore, a new PET degradation system needs to be provided. Utility Model Content

[0009] In order to solve the problems existing in the prior art, the utility model provides a safe and environmentally friendly waste plastic degradation system, which solves the problems of difficult temperature control and low stirring efficiency in the existing reaction system, and the entire degradation reaction is completed in one reaction device, the product quality is controllable, and ethylene glycol in the reaction by-product is recovered, solving the problem of by-products that are difficult to recover in traditional reaction devices.

[0010] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a safe and environmentally friendly waste plastic degradation system, wherein a reaction device is arranged on an integrated stirring and heating device, a temperature measuring device is arranged in the reaction device, a first inlet of the reaction device is connected to an outlet of a nitrogen device, a second inlet of the reaction device is connected to a condensing device, a third inlet of the reaction device is used to introduce reaction raw materials, the outlet of the reaction device is connected to an inlet of a suction filtration device, and the outlet of the suction filtration device is connected to an inlet of a degradation product collection device.

[0011] Furthermore, it also includes a drying device for drying the degradation products in the degradation product collecting device.

[0012] Furthermore, the filtration device comprises a boiling water filtration part and a vacuum filtration part, and the filter residue outlets of the boiling water filtration part and the vacuum filtration part are both connected to the inlet of the degradation product collection device.

[0013] Furthermore, the temperature adjustment range of the integrated stirring and heating device is 180°C to 200°C.

[0014] Furthermore, a temperature measuring device is arranged in the third inlet of the reaction device for detecting the reaction temperature in the reaction device.

[0015] Furthermore, the outlet of the reaction device is connected to the first inlet of the suction filtration device, the first outlet of the suction filtration device is connected to the inlet of the filtrate collecting device, the outlet of the filtrate collecting device is connected to the second inlet of the suction filtration device, the second outlet of the suction filtration device is connected to the inlet of the by-product collecting device, and the third outlet of the suction filtration device is connected to the inlet of the degradation product collecting device.

[0016] Furthermore, the filtration device includes a boiling water filtration part and a vacuum filtration part. The boiling water filtration part is between the first inlet and the first outlet of the filtration device, and the vacuum filtration part is between the second inlet and the second outlet of the filtration device.

[0017] Furthermore, the second outlet of the suction filtration device is connected to the inlet of the vacuum distillation device, and the outlet of the vacuum distillation device is connected to the inlet of the by-product collection device.

[0018] Furthermore, it also includes a low-temperature cooling device for reducing the filtrate temperature in the filtrate collecting device to 4°C to 6°C.

[0019] Compared with the prior art, the utility model has at least the following beneficial effects:

[0020] The utility model provides a safe and environmentally friendly waste plastic degradation system. By arranging an integrated stirring and heating device and a temperature measuring device, uniform stirring of materials in a reaction device and precise temperature control are achieved, and the problems of difficult temperature control and low stirring efficiency in the existing reaction system are solved. Furthermore, in the system, a degradation reaction is carried out in a reaction device at one time to obtain a degradation product, a condensing device is used to reflux the gaseous substances produced in the reaction device, and finally a suction filtration device is used to obtain a PET degradation product. The reaction efficiency and output are high, and because the amount of raw materials added to the reaction device has been determined, the product quality is also easy to control.

[0021] Furthermore, the utility model realizes the recovery of by-products by cooperating the vacuum filtration part of the filtration device with the filtrate collecting device, the by-product collecting device, the low-temperature cooling device, and the vacuum distillation device, thereby effectively solving the problem that by-products produced by the reaction of traditional devices are difficult to recover.

[0022] In summary, the PET degradation system can alcoholyze PET under relatively mild conditions, reduce the loss of raw materials and waste of fuel, and obtain relatively pure degradation products. It is simple to operate, has accurate temperature control, and uniform stirring. It is a safe and environmentally friendly PET degradation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of a safe and environmentally friendly waste plastic degradation system;

[0024] Figure 2 Example 1 Experimental setup diagram. DETAILED DESCRIPTION

[0025] The utility model is further described below in conjunction with the accompanying drawings and specific implementation methods.

[0026] like Figure 1 As shown, the utility model provides a safe and environmentally friendly waste plastic degradation system, including: a reaction device 1, an integrated stirring and heating device 2, a nitrogen device 3, a temperature measuring device 4, a condensing device 5, a suction filtration device 6, a drying device 7, a degradation product collection device 8, a by-product collection device 9, a filtrate collection device 10, and a low-temperature cooling device 11, wherein:

[0027] The reaction device 1 is arranged on the integrated stirring and heating device 2, which is used to stir and control the temperature of the reaction solution in the reaction device 1, so as to achieve sufficient mixing of the reaction raw materials and improve the degree of reaction, wherein the temperature adjustment range of the integrated stirring and heating device 2 is 180°C to 200°C;

[0028] The first inlet of the reaction device 1 is connected to the outlet of the nitrogen device 3 for introducing nitrogen into the reaction device 1, the second inlet of the reaction device 1 is connected to the condensing device 5 for realizing the reflux of the reaction steam, and the third inlet of the reaction device 1 is used for introducing the reaction raw materials;

[0029] The temperature measuring device 4 is used to monitor the reaction temperature in the reaction device 1, which solves the problem that traditional devices cannot measure temperature sensitively, and can transmit temperature data to the integrated stirring and heating device 2. The temperature of the integrated stirring and heating device 2 is gently adjusted according to the temperature data of the temperature measuring device 4, thereby ensuring the safety of the degradation system.

[0030] The outlet of the reaction device 1 is connected to the first inlet of the suction filtration device 6 to pass the degradation product of PET into the suction filtration device 6 and perform boiling water filtration to obtain a first filtrate and a first filter residue (degradation product R-PET);

[0031] The filtration device 6 includes a boiling water filtration part and a vacuum filtration part. The boiling water filtration part is between the first inlet and the first outlet of the filtration device 6, and the vacuum filtration part is between the second inlet and the second outlet of the filtration device 6. The filter residues obtained from the boiling water filtration part and the vacuum filtration part are both sent to the degradation product collection device 8 through the third outlet.

[0032] The first outlet of the suction filtration device 6 is connected to the inlet of the filtrate collecting device 10 for passing the first suction filtrate into the filtrate collecting device 10 for low temperature sedimentation at 4°C to 6°C for 9 to 11 hours, and the outlet of the filtrate collecting device 10 is connected to the second inlet of the suction filtration device 6 for passing the filtrate after low temperature sedimentation into the suction filtration device 6 for secondary suction filtration to obtain the second filtrate and the second filter residue (degradation product R-PET);

[0033] The second outlet of the suction filtration device 6 is connected to the inlet of the by-product collection device 9 for collecting the second suction filtration filtrate, and performing reduced pressure distillation to obtain ethylene glycol as a by-product.

[0034] The third outlet of the filtration device 6 is connected to the inlet of the degradation product collecting device 8, and is used to collect the first filtration residue and the second filtration residue. The degradation product collecting device 8 is placed in the drying device 7 to dry the residue at a temperature of 50 to 70° C. for 5 to 7 hours to obtain the product after PET alcoholysis (R-PET).

[0035] It also includes a low-temperature cooling device 11 for low-temperature precipitation of the filtrate in the filtrate collecting device 10 .

[0036] When the system of the utility model is used, the devices are connected according to the connection relationship of the above devices:

[0037] PET and alcoholysis reactants are introduced into the reaction device 1 through the third inlet of the reaction device 1, and the nitrogen device 3 purges nitrogen into the reaction device 1 to remove oxygen in the reaction device 1 and prevent oxidation and decomposition of the reaction alcohol; at the same time, the second inlet of the reaction device 1 is connected to the inlet of the condensation device 5. This connection method makes the reaction easy, the instrument operation is simple, and the product quality is easy to control during the process, thereby improving efficiency and output, and solving the problem of cumbersome operation of traditional devices;

[0038] The integrated stirring and heating device 2 is turned on to heat and stir the PET and the alcoholysis reactants in the reaction device 1. After reaching the set temperature, the PET and the alcoholysis reactants in the reaction device 1 are degraded, and the steam generated by the degradation reaction flows back into the reaction device 1 under the action of the condensing device 5;

[0039] The temperature measuring device 4 detects the temperature in the reaction device 1 in real time, and adjusts the temperature of the integrated stirring and heating device 2 according to the temperature displayed by the temperature measuring device 4;

[0040] After the first degradation is completed, the nitrogen device 3 and the condensation device 5 are closed; the reaction product is sent to the suction filtration device 6 through the outlet of the reaction device 1, and the first suction filtration is performed with boiling water. After the first suction filtration, the first suction filtration filtrate and the first suction filtration residue (degradation product R-PET) are obtained:

[0041] The first suction filtration filtrate is sent to the filtrate collecting device 10, and the low temperature cooling device 11 adjusts the temperature of the filtrate collecting device 10 to 4-6°C for 9-11 hours of low temperature precipitation; a large amount of white flocculent crystals are precipitated in the filtrate, and after the solid and the liquid are separated, the filtrate separated after the crystals are precipitated is sent to the suction filtration device 6 for suction filtration again, and the second suction filtration filtrate and the second suction filtration residue are sent to the degradation product collecting device 8 after suction filtration, and the drying device 7 dries the second suction filtration residue in the degradation product collecting device 8 to obtain the product (R-PET) after PET alcoholysis;

[0042] The second filtration filtrate is sent to the by-product collection device 9, and the second filtration filtrate is subjected to reduced pressure distillation to obtain ethylene glycol in the by-product, thereby collecting the by-product. This process solves the problem that the traditional experimental device cannot recycle the by-product, and can avoid the accumulation of by-products, environmental pollution and waste of resources.

[0043] The final degradation product is pure, and the by-product can be reused, which increases the added value of the experiment and meets the requirements of environmental protection. The system can alcoholyze PET under mild conditions, reduce the loss of raw materials and waste of fuel, and obtain purer degradation products. The instrument is easy to operate, has accurate temperature control, and even stirring. It is a safe and environmentally friendly PET alcoholysis instrument.

[0044] Example 1

[0045] like Figure 2 As shown, the utility model provides a safe and environmentally friendly waste plastic degradation system, wherein:

[0046] The reaction device 1 uses a three-necked flask, the content of the three-necked flask is 500ml, and the material is glass; the reaction raw materials are put into the three-necked flask from the inlet of any three-necked flask;

[0047] The integrated stirring and heating device 2 adopts an electric heating jacket integrating temperature control, magnetic stirring and heating, and the magnetic stirring adopts a polytetrafluoroethylene magnetic stirring bar;

[0048] Nitrogen device 3 selects HPT-8 quantitative nitrogen blowing concentrator;

[0049] The temperature measuring device 4 uses a mercury thermometer. The electric heating jacket that integrates temperature control, magnetic stirring and heating can accurately measure the temperature with the help of the mercury thermometer, making the entire experimental device safer.

[0050] The condensing device 5 selects a spherical condensing tube;

[0051] The filtration device 6 uses SHZ-D ABS corrosion-resistant circulating water vacuum pump, with a water tank capacity of 15L and a product size of 400*280*420mm;

[0052] The drying device 7 is a vacuum drying oven;

[0053] The degradation product collecting device 8 adopts a wide-mouth bottle;

[0054] The by-product collecting device 9 adopts a conical flask;

[0055] The filtrate collecting device 10 adopts a suction filtration bottle;

[0056] The low temperature cooling device 11 is a refrigerator;

[0057] Among them, the use of a three-necked flask is to control the order in which the reactants are introduced so that the reaction proceeds in a set order.

[0058] When degrading:

[0059] A polytetrafluoroethylene magnetic stirring bar is placed in a three-necked flask, and the cut PET fragments, a certain amount of zinc acetate, and a certain amount of ethylene glycol EG are added into the three-necked flask in sequence. The three ports of the three-necked flask are connected to a condenser, a thermometer, and a nitrogen device from left to right in sequence. After nitrogen is introduced into the three-necked flask for a period of time, the integrated stirring and heating device 2 heats the three-necked flask, and adjusts the rotation speed of the polytetrafluoroethylene magnetic stirring bar until the reaction is completed. The polytetrafluoroethylene magnetic stirring bar stirs the bottom of the three-necked flask, thereby making the reaction more complete.

[0060] The optimal process parameters for alcoholysis of recycled PET determined through research are that the amount of EG is 6 times the mass of PET, the reaction temperature is 190°C, and the reaction time is 3h.

[0061] After the reaction is completed, the reaction product is filtered with boiling water using a vacuum pump to obtain a filtrate and a filter residue after the first filtration. The filter residue is placed on filter paper, which is placed in a vacuum drying oven to dry the filter paper and the surface residue to remove moisture, and then weighed to obtain the product after PET alcoholysis (R-PET).

[0062] The filtrate after the first filtration was all introduced into a conical flask. After refrigeration at 5°C for about 10 hours, sedimentation occurred in the filtrate and a large amount of white flocculent crystals were precipitated. The solid and liquid were separated by a funnel, and the filtrate separated after the crystals were precipitated was filtered again with a vacuum pump to obtain solid and liquid. The solid obtained after the second filtration was the product after PET alcoholysis (R-PET).

[0063] Then the product after alcoholysis of PET is dried in a vacuum drying oven at 60°C for 6 hours to obtain a solid substance, which is the degradation product;

[0064] The liquid obtained by the second filtration is distilled under reduced pressure to obtain ethylene glycol as a by-product.

[0065] In this embodiment, the reaction vessel is selected to be a three-necked flask. Since it has a narrow mouth, it has the function of preventing the solution from splashing or volatilizing. At the same time, the use of a rubber stopper can be coordinated to connect other glass equipment such as a thermometer and a glass tube, so as to achieve the function of measuring the material temperature at any time and controlling the reaction at any time. When PET is degraded, only the reactants need to be added to the three-necked flask in sequence, and the degradation product can be obtained after the operation is performed according to the steps, so the device can achieve the purpose of completing the alcoholysis of PET in one experiment, and the accuracy of the experimental scheme is guaranteed to a certain extent. The device is simple to operate, and the temperature control is accurate, and the reaction time can be accurately controlled. It is a highly efficient and practical device for alcoholysis of PET.

Claims

1. A safe and environmentally friendly waste plastic degradation system, characterized in that: The reaction device (1) is arranged on the integrated stirring and heating device (2), the temperature measuring device (4) is arranged in the reaction device (1), the first inlet of the reaction device (1) is connected to the outlet of the nitrogen device (3), the second inlet of the reaction device (1) is connected to the condensing device (5), the third inlet of the reaction device (1) is used to introduce reaction raw materials, the outlet of the reaction device (1) is connected to the inlet of the suction filtration device (6), the suction filtration device (6) comprises a boiling water suction filtration part and a vacuum suction filtration part, and the filter residue outlets of the boiling water suction filtration part and the vacuum suction filtration part are both connected to the inlet of the degradation product collection device (8).

2. A safe and environmentally friendly waste plastic degradation system according to claim 1, characterized in that: It also includes a drying device (7) for drying the degradation products in the degradation product collecting device (8).

3. A safe and environmentally friendly waste plastic degradation system according to claim 1, characterized in that: The temperature adjustment range of the integrated stirring and heating device (2) is 180°C to 200°C.

4. A safe and environmentally friendly waste plastic degradation system according to claim 1, characterized in that: The temperature measuring device (4) is arranged in the third inlet of the reaction device (1) and is used to detect the reaction temperature in the reaction device (1).

5. A safe and environmentally friendly waste plastic degradation system according to claim 1, characterized in that: The outlet of the reaction device (1) is connected to the first inlet of the suction filtration device (6), the first outlet of the suction filtration device (6) is connected to the inlet of the filtrate collection device (10), the outlet of the filtrate collection device (10) is connected to the second inlet of the suction filtration device (6), the second outlet of the suction filtration device (6) is connected to the inlet of the by-product collection device (9), and the third outlet of the suction filtration device (6) is connected to the inlet of the degradation product collection device (8).

6. A safe and environmentally friendly waste plastic degradation system according to claim 5, characterized in that: A boiling water filtration section is located between the first inlet and the first outlet of the filtration device (6), and a vacuum filtration section is located between the second inlet and the second outlet of the filtration device (6).

7. A safe and environmentally friendly waste plastic degradation system according to claim 5, characterized in that: The second outlet of the suction filtration device (6) is connected to the inlet of the vacuum distillation device, and the outlet of the vacuum distillation device is connected to the inlet of the by-product collection device (9).

8. A safe and environmentally friendly waste plastic degradation system according to claim 5, characterized in that: It also includes a low-temperature cooling device (11) for reducing the temperature of the filtrate in the filtrate collecting device (10) to 4°C to 6°C.

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