A polypropylene carbonate pellet conveying device

Abstract

The utility model belongs to polypropylene carbonate production technical field relates to a kind of polypropylene carbonate granular material conveying devices, including buffer hopper, outlet pipeline has first plug-in valve, first rotary valve and first valve;Blending bin, first import is connected with the outlet pipeline of buffer hopper by blending feeding pipeline, second import is connected with the internal circulation pipeline of its outlet pipeline communication, outlet pipeline is equipped with second plug-in valve and second rotary valve;Elutriator, import connection and blending bin outlet pipeline intercommunication blending feeding pipeline;Packaging bin, with elutriator outlet communication;Low-temperature air supply unit, compressor and heat exchanger, the air of compressor delivery is formed low-temperature cold air after heat exchange, low-temperature cold air and blending feeding pipeline, internal circulation pipeline, elutriation feeding pipeline communication.It has the advantages that material sticking is avoided, impact damage is reduced, and the performance of PPC granular material is stable.

Description

Technical Field

[0001] This utility model belongs to the field of polypropylene carbonate production technology, and in particular relates to a polypropylene carbonate granule conveying device. Background Technology

[0002] Polypropylene carbonate (PPC), as an environmentally friendly and biodegradable polymer material, is increasingly widely used in packaging, injection molding, and other fields. In the industrial production of PPC, the conveying of granules is a crucial step connecting granulation, storage, and processing. Currently, the industry mostly uses traditional pneumatic conveying technology for granule transfer, that is, using ambient temperature air as the conveying medium.

[0003] However, polypropylene carbonate granules have strong molecular chain polarity and poor heat resistance. In traditional pneumatic conveying processes, the high-speed friction between the granules and the inner wall of the pipe, as well as between the granules themselves, generates significant heat. This causes the local temperature inside the pneumatic conveying pipe to rise above 40°C, exceeding the glass transition temperature of polypropylene carbonate. This leads to softening of the granule surface, increased stickiness, and problems such as adhesion to the inner wall of the pipe and granule agglomeration. In severe cases, this can cause pipe blockage and affect production efficiency. At the same time, frictional heating can also degrade the mechanical properties of polypropylene carbonate granules, reducing the product qualification rate.

[0004] Therefore, it is urgent to solve the problem of conveying polypropylene carbonate granules. Utility Model Content

[0005] This utility model provides a polypropylene carbonate granule conveying device that uses low-temperature pneumatic conveying to avoid material sticking, reduce collision damage, and ensure the stable performance of PPC granules.

[0006] The technical solution of this utility model includes: a polypropylene carbonate granular material conveying device, comprising: a buffer hopper, the discharge pipeline of which is equipped with a first gate valve, a first rotary valve, and a first valve; and a mixing silo, the first inlet of which is connected to the discharge pipeline of the buffer hopper via a mixing feed pipeline, the second inlet of which is connected to an internal circulation pipeline, the internal circulation pipeline being connected to the discharge pipeline of the mixing silo, and the discharge pipeline of the mixing silo being equipped with a second gate valve and a second rotary valve. The washing device includes an inlet connected to a washing feed pipeline, which is connected to the outlet pipeline of the mixing silo; a packaging silo, the inlet of which is connected to the outlet of the washing device via a pipeline; and a low-temperature air supply unit, which includes a compressor and a heat exchanger connected to the compressor. The air supplied by the compressor is heated by the heat exchanger to form low-temperature cold air, which is connected to the mixing feed pipeline, the internal circulation pipeline, and the washing feed pipeline.

[0007] Preferably, the corners of the mixing feed pipeline, the internal circulation pipeline, and the washing feed pipeline are provided with elbow structures.

[0008] Preferably, the elbow structure includes straight pipe sections at both ends and a transition section connecting the two ends of the straight pipe sections, the two ends of the straight pipe sections are perpendicular to each other, and the outer wall of the transition section is provided with an inclined plate.

[0009] Preferably, the two ends of the inclined plate are connected to the outer wall of the straight pipe section, and the inclination angle of the inclined plate is 40° to 50°.

[0010] Preferably, the mixing and feeding pipeline is equipped with a mixing and feeding shoe, the first interface of the mixing and feeding shoe is connected to the discharge pipeline of the buffer hopper, the second interface of the mixing and feeding shoe is connected to the low-temperature cold air, and the third interface of the mixing and feeding shoe is connected to the mixing and feeding pipeline.

[0011] Preferably, the internal circulation pipeline is equipped with an internal circulation feeding shoe, the first interface of the internal circulation feeding shoe is connected to the discharge pipeline of the mixing silo, the second interface of the internal circulation feeding shoe is connected to the low-temperature cold air, and the third interface of the internal circulation feeding shoe is connected to the internal circulation pipeline.

[0012] Preferably, the washing and feeding pipeline is equipped with a washing and feeding shoe, the first interface of the washing and feeding shoe is connected to the discharge pipeline of the mixing silo, the second interface of the washing and feeding shoe is connected to the low-temperature cold air, and the third interface of the washing and feeding shoe is connected to the washing and feeding pipeline.

[0013] Preferably, the blending feed line and the washing feed line are equipped with reversing valves, and the discharge line of the blending silo includes a first branch discharge line and a second branch discharge line. The first branch discharge line is connected to the internal circulation line, and the second branch discharge line is connected to the washing feed line. The first branch discharge line and the second branch discharge line are equipped with reversing valves.

[0014] Preferably, the heat exchanger is connected to a low-temperature water inlet pipe and a low-temperature water outlet pipe, and the water temperature in the low-temperature water outlet pipe is not higher than 10°C.

[0015] The beneficial effects of this utility model are as follows: By designing a low-temperature air supply unit, a heat exchanger is used to cool the air supplied by the compressor, forming low-temperature cold air for conveying PPC granules. This avoids the problem of material sticking caused by conveying PPC granules with room-temperature air. Simultaneously, a first gate valve, a first rotary valve, and a first valve are designed in the discharge pipeline of the buffer hopper. The first gate valve and the first rotary valve control the discharge load of PPC granules from the buffer hopper, enabling coordination between the feeding amount and airflow of the low-temperature cold air to avoid excessive collisions between PPC granules during cold air feeding. This design aims to prevent damage to PPC granules and thus avoid performance degradation caused by particle collisions. Simultaneously, a blending silo and a washing machine are designed to perform self-blending, purification, degassing, and dust removal on the PPC granules. An internal circulation pipeline is designed in the blending silo, and washing and feeding pipelines are designed in both the blending silo and the washing machine. Furthermore, both the internal circulation pipeline and the washing and feeding pipeline are connected to low-temperature cold air, which is used to transport the PPC granules during their self-blending, purification, degassing, and dust removal processes, thereby improving the overall conveying efficiency of the PPC granules. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of this embodiment;

[0018] Figure 2 This is a schematic diagram of the elbow structure in this embodiment.

[0019] in:

[0020] 1. Vibrating screen; 2. Buffer hopper; 21. First slide gate valve; 22. First rotary valve; 23. First valve; 3. Blending feed pipeline; 31. Blending feed shoe; 4. Blending silo; 41. Second slide gate valve; 42. Second rotary valve; 5. Internal circulation pipeline; 51. Internal circulation feed shoe; 52. Internal circulation valve; 6. Washing feed pipeline; 61. Washing feed shoe; 62. Washing valve; 7. Washer; 71. Third rotary valve; 8. Packaging silo; 9. Compressor; 10. Heat exchanger; 11. Low-temperature water inlet pipe; 12. Low-temperature water outlet pipe; 20. Reversing valve; 30. Elbow structure; 301. Inclined plate. Detailed Implementation

[0021] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] In this document, terms such as "above," "below," "left," "right," "inner," and "outer" are established based on the positional relationships shown in the accompanying drawings. Depending on the drawings, these positional relationships may change; therefore, they should not be construed as absolute limitations on the scope of protection. Furthermore, relational terms such as "first" and "second" are merely used to distinguish one component from another with the same name, and do not necessarily require or imply any actual relationship or order between these components. In addition, in embodiments of this utility model, "above," "below," etc., include the stated number.

[0023] The PPC granule conveying device and method of this embodiment addresses the issue that existing PPC granule conveying methods often employ ambient temperature conveying. However, ambient temperature conveying can easily lead to pipe overheating due to friction during the conveying process, resulting in PPC granule sticking. To address this, this embodiment seeks a solution to prevent PPC granule sticking during conveying and to avoid performance degradation caused by material sticking.

[0024] It is also noted that low-temperature pneumatic conveying processes are currently used in the conveying of heat-sensitive granular materials such as ethylene-vinyl acetate copolymer (EVA). However, PPC and EVA have many differences. For example, their molecular structures, heat resistance, and surface properties are significantly different. PPC is more polar and has a lower softening temperature. If the low-temperature pneumatic conveying process for EVA is directly applied, the problems of adhesion and low efficiency in conveying PPC granules will still not be solved.

[0025] Based on the above practical difficulties, this embodiment provides a conveying device and method for PPC granules.

[0026] On the one hand, this embodiment provides a polypropylene carbonate granule conveying device.

[0027] Reference Figure 1 and Figure 2 The polypropylene carbonate granule conveying device of this embodiment includes a buffer hopper 2, a mixing hopper 4, a washing machine 7, a packaging hopper 8, and a low-temperature air supply unit.

[0028] The discharge pipeline of the buffer hopper 2 is equipped with a first gate valve 21, a first rotary valve 22, and a first valve 23. By designing the first gate valve 21 and the first rotary valve 22 in the discharge pipeline of the buffer hopper 2, the discharge load of the PPC granules in the buffer hopper 2 can be precisely controlled by adjusting both synchronously. This facilitates coordination with the low-temperature cold air volume used for conveying the granules, avoiding damage caused by excessive collisions during conveying due to excessive air volume, and also avoiding insufficient conveying power due to insufficient air volume. Specifically, the first gate valve 21, the first rotary valve 22, and the first valve 23 can adopt conventional valve structures. The specific valve structure is not the focus of improvement in this embodiment and will not be elaborated here.

[0029] The first inlet of the blending silo 4 is connected to the discharge pipeline of the buffer hopper 2 via the blending feed pipeline 3, thereby conveying the PPC granules discharged from the buffer hopper 2 to the blending silo 4 through the blending feed pipeline 3. The second inlet of the blending silo 4 is connected to an internal circulation pipeline 5, which is connected to the discharge pipeline of the blending silo 4. That is, the blending silo 4 is also designed with an internal circulation pipeline 5, which allows the PPC granules discharged from the blending silo 4 to re-enter the blending silo 4, thereby achieving self-blending and purification degassing of the PPC granules and improving the uniformity and quality of the PPC granules. The discharge pipeline of the mixing silo 4 is designed with a second gate valve 41 and a second rotary valve 42. The synchronous adjustment of the two can accurately control the discharge load of the PPC granules discharged from the mixing silo 4, so as to improve the coordination with the air volume of the low temperature cold air conveying it, so as to avoid damage caused by excessive collision of PPC granules during conveying due to excessive air volume, and also to avoid insufficient conveying power of PPC granules due to insufficient air volume.

[0030] The inlet of the washing machine 7 is connected to a washing and feeding pipeline 6, which is connected to the outlet pipeline of the mixing silo 4. This allows the PPC granules discharged from the mixing silo 4 to be transported to the washing machine 7 via the washing and feeding pipeline 6. The washing machine 7 performs dust removal and purification on the PPC granules. The inlet of the packaging silo 8 is connected to the outlet of the washing machine 7 via a pipeline, allowing the dust-removed and purified PPC granules to be transported to the packaging silo 8 for storage, awaiting subsequent packaging and storage.

[0031] The low-temperature air supply unit includes a compressor 9 and a heat exchanger 10 connected to the compressor 9. The air supplied by the compressor is heated in the heat exchanger 10 to form low-temperature cold air. This low-temperature cold air is connected to the blending feed line 3, the internal circulation line 5, and the washing feed line 6. This allows for the use of low-temperature cold air to transport PPC granules. Low-temperature cold air is used in multiple transport processes: from the buffer hopper 2 to the blending silo 4, through internal circulation in the blending silo 4 for blending and purification / degassing, and from the blending silo 4 to the washing machine 6. This ensures the performance of the PPC granules during transport and improves transport efficiency.

[0032] The PPC granule conveying device in this embodiment uses low-temperature cold air to convey PPC granules, which can avoid the problem of material sticking caused by friction heating during conveying. Furthermore, the coordinated control of the conveying air volume and the amount of PPC material can avoid particle damage caused by excessive collision of PPC granules during conveying. This can avoid the adverse effects of material sticking and collision damage on the performance of PPC granules, ensuring the material performance of PPC granules in low-temperature pneumatic conveying. Moreover, the use of low-temperature pneumatic conveying at multiple conveying and transfer nodes can improve the overall device's ability to ensure the performance of PPC granules and also improve the feeding efficiency of PPC granules.

[0033] In this specific implementation, elbow structures 30 are provided at the corners of the mixing and feeding pipeline 3, the internal circulation pipeline 5, and the washing and feeding pipeline 6. The elbow structure 30 can reduce the friction coefficient between PPC particles and the pipeline, reduce local frictional heating and particle accumulation, and further reduce the risk of adhesion.

[0034] Specifically, the elbow structure 30 includes straight pipe sections at both ends and a transition section connecting the two straight pipe sections. The straight pipe sections at both ends are perpendicular to each other to achieve a smooth connection at the corner of the pipeline. The outer wall of the transition section is provided with an inclined plate 301, where the outer wall refers to the outward side of the corner. The inclined plate 301 enables tangential conveying of PPC granules when passing through the corner elbow, reducing friction between the material and the pipeline and reducing the generation of stringy material. More specifically, the two ends of the inclined plate 301 are connected to the outer wall of the straight pipe section. The inclination angle of the inclined plate 301 is 40° to 50°, preferably 45°, so as to achieve 90° tangential conveying of the material when passing through the elbow, further improving the effect of reducing friction between the material and the pipeline and reducing the generation of stringy material.

[0035] The mixing and feeding pipeline 3 is equipped with a mixing feed shoe 31. The first interface of the mixing feed shoe 31 is connected to the discharge pipeline of the buffer hopper 2, the second interface of the mixing feed shoe 31 is connected to the low-temperature cold air, and the third interface of the mixing feed shoe 31 is connected to the mixing and feeding pipeline 3. By using the mixing feed shoe 31, the discharge pipeline of the buffer hopper 2, the conveyed low-temperature cold air, and the mixing and feeding pipeline 3 can be connected.

[0036] Similarly, the internal circulation pipeline 5 is equipped with an internal circulation feeding shoe 51. The first interface of the internal circulation feeding shoe 51 is connected to the discharge pipeline of the mixing silo 4, the second interface of the internal circulation feeding shoe 51 is connected to the low-temperature cold air, and the third interface of the internal circulation feeding shoe 51 is connected to the internal circulation pipeline 5. The washing and feeding pipeline 6 is equipped with a washing feeding shoe 61. The first interface of the washing feeding shoe 61 is connected to the discharge pipeline of the mixing silo 4, the second interface of the washing feeding shoe 61 is connected to the low-temperature cold air, and the third interface of the washing feeding shoe 61 is connected to the washing and feeding pipeline 6.

[0037] The blending feed line 3 and the washing feed line 6 are equipped with reversing valves 20 to switch the direction of PPC granular material conveying. The discharge lines of the blending silo 4 include a first branch discharge line and a second branch discharge line. The first branch discharge line is connected to the internal circulation line 5, and the second branch discharge line is connected to the washing feed line 6. Both the first and second branch discharge lines are equipped with reversing valves 20. By designing two branch discharge lines, independent conveying with the internal circulation line 5 and the washing feed line 6 can be achieved, improving the precise control of PPC granular material conveying. Specifically, the discharge lines of the blending silo 4 have a main discharge line connected to its discharge port, which is connected to both the first and second branch discharge lines. A second gate valve 41 and a second rotary valve 42 are installed on the main discharge line. An internal circulation valve 52 is installed on the first branch discharge line, and a washing valve 62 is installed on the second branch discharge line.

[0038] The heat exchanger 10 is connected to a low-temperature water inlet pipe 11 and a low-temperature water outlet pipe 12. The water temperature in the low-temperature water outlet pipe 12 does not exceed 10°C. That is, the low-temperature water in the heat exchanger 10 is used to cool the air in the compressor 9 to about 10°C to achieve a suitable temperature for conveying PPC granules. For example, the low-temperature water in the low-temperature water inlet pipe 11 can be controlled at about 5°C, and the low-temperature water in the low-temperature water outlet pipe 12 can be controlled at about 10°C to keep the low-temperature cold air at about 10°C.

[0039] On the other hand, this embodiment also provides a method for conveying polypropylene carbonate granules, including the above-mentioned polypropylene carbonate granule conveying device, wherein the conveying steps of the polypropylene carbonate granules include:

[0040] The first gate valve 21 and the first rotary valve 22 of the discharge pipeline of the buffer hopper 2 are adjusted synchronously to control the discharge load of polypropylene carbonate granules in the buffer hopper 2.

[0041] The low-temperature cold air generated by the low-temperature air supply unit is used to transport the polypropylene carbonate granules discharged from the buffer hopper 2 to the blending silo 4 through the blending and feeding pipeline 3.

[0042] The second gate valve 41 and the second rotary valve 42 of the discharge pipeline of the blending silo 4 are adjusted synchronously to control the discharge load of polypropylene carbonate granules in the blending silo 4. The polypropylene carbonate granules discharged from the blending silo 4 are re-entered into the blending silo 4 through the internal circulation pipeline 5 using low temperature cold air to perform self-blending and purification degassing of the polypropylene carbonate granules.

[0043] The second gate valve 41 and the second rotary valve 42 of the discharge pipeline of the blending silo 4 are adjusted synchronously to control the discharge load of polypropylene carbonate granules in the blending silo 4. The polypropylene carbonate granules discharged from the blending silo 4 are sent into the washing machine 7 through the washing and feeding pipeline 6 using low-temperature cold air. The polypropylene carbonate granules are then cleaned and dust removed in the washing machine 7. After being cleaned and dust removed, the polypropylene carbonate granules are discharged from the washing machine 7 and enter the packaging silo 8.

[0044] Specifically, the PPC granules in the buffer hopper 2 originate from the vibrating screen 1. After being extruded and pelletized by a twin-screw extruder, the PPC granules are first fed into the vibrating screen 1 for screening. Under the action of the vibrating screen 1, the qualified PPC granules pass smoothly through the screen and fall into the buffer hopper 2. A third rotary valve 71 is designed in the connecting pipeline between the washing machine 7 and the packaging hopper 8 to ensure that the PPC granules are stably transported from the washing machine 7 to the packaging hopper 8, where they await subsequent packaging and storage.

[0045] The polypropylene carbonate (PPC) granule conveying device and method of this embodiment can solve the problem of PPC granule adhesion during conveying. Through the coordinated control of low-temperature medium and gradient airflow, the temperature of the conveying medium can be precisely controlled at ≤20℃, and the flow rate can be matched with 1000-3000 Nm depending on the conveying distance (10-100m). 3With a gradient airflow rate of / h, the maximum temperature of polypropylene carbonate granules inside the pipeline during pneumatic conveying is ≤30℃, far below its softening temperature. After pneumatic conveying, the granule adhesion rate is ≤1.5%, and the pipeline blockage rate is reduced to below 0.1%, a significant improvement over traditional ambient temperature pneumatic conveying processes (adhesion rate 15-20%). Furthermore, it ensures stable performance of the conveyed PPC granules; there is no significant temperature rise during low-temperature pneumatic conveying, and the retention rate of mechanical properties (tensile strength, elongation at break) is ≥98%, avoiding material deterioration caused by frictional heating in traditional pneumatic conveying. The product qualification rate is increased to over 99.5%. In addition, it boasts high conveying efficiency and wide adaptability, enabling continuous conveying over long distances of 10-100m. A single unit can convey 5-50t per hour, adapting to polypropylene carbonate granules of different particle sizes to meet the conveying needs of large-scale production. Furthermore, the elbow structure reduces the friction coefficient between particles and the pipe. Arc-shaped buffer structures are set at pipe elbows, inlets, and outlets to reduce local frictional heat generation and particle accumulation, further reducing the risk of adhesion.

[0046] Where the embodiments do not contradict each other, at least some of the technical solutions in each embodiment can be recombine to form the essential technical solution of this utility model. Of course, the embodiments can also reference or include each other. Furthermore, it should be noted that adaptive adjustments and modifications made by those skilled in the art when recombinating the technical means described in the embodiments will also fall within the protection scope of this utility model.

[0047] The technical principles of this utility model have been described above in conjunction with specific embodiments. However, it should be noted that these descriptions are merely for explaining the principles of this utility model and should not be construed as limiting the scope of protection of this utility model in any way. Based on this explanation, other specific embodiments or equivalent substitutions of this utility model that can be conceived by those skilled in the art without creative effort will all fall within the scope of protection of this utility model.

Claims

1. A polypropylene carbonate granule conveying device, characterized in that, include: The buffer hopper (2) has a discharge pipeline equipped with a first slide gate valve (21), a first rotary valve (22) and a first valve (23); The mixing silo (4) has a first inlet connected to the discharge pipeline of the buffer hopper (2) via a mixing feed pipeline (3), and a second inlet connected to an internal circulation pipeline (5) connected to the discharge pipeline of the mixing silo (4). The discharge pipeline of the mixing silo (4) is equipped with a second gate valve (41) and a second rotary valve (42). Washer (7), the inlet of which is connected to a washing feed line (6), which is connected to the discharge line of the mixing silo (4); Packaging hopper (8), the inlet of which is connected to the outlet of the washing machine (7) via a pipeline; The low-temperature air supply unit includes a compressor (9) and a heat exchanger (10) connected to the compressor (9). The air supplied by the compressor (9) is heated by the heat exchanger (10) to form low-temperature cold air. The low-temperature cold air is connected to the mixing feed line (3), the internal circulation line (5) and the washing feed line (6).

2. The polypropylene carbonate granule conveying device according to claim 1, characterized in that: The corners of the mixing and feeding pipeline (3), the internal circulation pipeline (5) and the washing and feeding pipeline (6) are provided with elbow structures (30).

3. The polypropylene carbonate granule conveying device according to claim 2, characterized in that: The elbow structure (30) includes straight pipe sections at both ends and a transition section connecting the straight pipe sections at both ends. The straight pipe sections at both ends are perpendicular to each other, and the outer wall of the transition section is provided with an inclined plate (301).

4. The polypropylene carbonate granule conveying device according to claim 3, characterized in that: The two ends of the inclined plate (301) are connected to the outer wall of the straight pipe section, and the inclination angle of the inclined plate (301) is 40° to 50°.

5. The polypropylene carbonate granule conveying device according to claim 1, characterized in that: The mixing and feeding pipeline (3) is equipped with a mixing and feeding shoe (31). The first interface of the mixing and feeding shoe (31) is connected to the discharge pipeline of the buffer hopper (2), the second interface of the mixing and feeding shoe (31) is connected to the low temperature cold air, and the third interface of the mixing and feeding shoe (31) is connected to the mixing and feeding pipeline (3).

6. The polypropylene carbonate granule conveying device according to claim 1, characterized in that: The internal circulation pipeline (5) is equipped with an internal circulation feeding shoe (51). The first interface of the internal circulation feeding shoe (51) is connected to the discharge pipeline of the mixing silo (4). The second interface of the internal circulation feeding shoe (51) is connected to the low temperature cold air. The third interface of the internal circulation feeding shoe (51) is connected to the internal circulation pipeline (5).

7. The polypropylene carbonate granule conveying device according to claim 1, characterized in that: The washing and feeding pipeline (6) is equipped with a washing and feeding shoe (61). The first interface of the washing and feeding shoe (61) is connected to the discharge pipeline of the mixing silo (4). The second interface of the washing and feeding shoe (61) is connected to the low temperature cold air. The third interface of the washing and feeding shoe (61) is connected to the washing and feeding pipeline (6).

8. The polypropylene carbonate granule conveying device according to claim 1, characterized in that: The mixing and feeding pipeline (3) and the washing and feeding pipeline (6) are equipped with reversing valves (20). The discharge pipeline of the mixing silo (4) includes a first branch discharge pipeline and a second branch discharge pipeline. The first branch discharge pipeline is connected to the internal circulation pipeline (5), and the second branch discharge pipeline is connected to the washing and feeding pipeline (6). The first branch discharge pipeline and the second branch discharge pipeline are equipped with reversing valves (20).

9. A polypropylene carbonate granule conveying device according to claim 1, characterized in that: The heat exchanger (10) is connected to a low-temperature water inlet pipe (11) and a low-temperature water outlet pipe (12), and the water temperature in the low-temperature water outlet pipe (12) is not higher than 10°C.

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