Polyester chip production polymerization reactor

Abstract

The application discloses a kind of polymeric reaction kettle for polyester chip production, belong to polymeric reaction kettle technical field, including kettle body and kettle cover, the kettle cover is installed on kettle body by bolt, stirring motor is installed on the kettle cover, the output shaft of stirring motor is fixedly installed with stirring shaft, the first stirring plate is externally equipped with the stirring shaft;In the application, the stirring effect of "tearing type" can effectively prevent high-viscosity material from hanging on kettle wall or stirring paddle and coking, reduce local overheating and thermal degradation of material, which not only reduces the color, acetaldehyde and other impurity content in the final product, but also ensures the uniformity of product molecular weight distribution, improves the overall quality of polyester chip, fully and efficiently stirred to shorten the reaction time required to reach target polymerization degree, improve production efficiency, at the same time, since avoiding local overheating and inefficient stirring, the overall energy consumption of the system is effectively controlled.

Description

Technical Field

[0001] This invention belongs to the field of polymerization reactor technology, and particularly relates to a polymerization reactor for polyester chip production. Background Technology

[0002] The main raw materials for producing polyester chips are purified terephthalic acid and ethylene glycol. These two raw materials undergo esterification and polycondensation reactions to produce polyethylene terephthalate, which is then granulated to form polyester chips.

[0003] Polyester chips typically refer to polyester raw materials obtained through polymerization. They are generally processed into sheet-like granules of about 4*5*2 mm. Their main applications include fibers, various containers, packaging materials, engineering plastics, and other fields. Polymerization reactors are required for their production.

[0004] The polymerization process of polyester chips requires stirring and mixing of raw materials. However, due to the stickiness between the raw materials, they stick together to a certain extent when stirred, resulting in incomplete mixing. This affects the mixing and polymerization results, and ultimately impacts the production quality of polyester chips.

[0005] Based on this, the present invention designs a polymerization reactor for polyester chip production to solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to provide a polymerization reactor for polyester chip production in order to solve the problems mentioned above in the background art.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A polymerization reactor for polyester chip production includes a reactor body and a reactor cover. The reactor cover is bolted to the reactor body. A stirring motor is mounted on the reactor cover. A stirring shaft is fixedly mounted on the output shaft of the stirring motor. A first stirring plate is provided outside the stirring shaft. A support ring is installed inside the reactor body. A rotating ring is rotatably connected inside the support ring. A second stirring plate is mounted on the inner arc surface of the rotating ring. Two sealing rings are provided at the curved contact portion between the rotating ring and the support ring. A limiting ring is provided inside the support ring and located on the upper side of the rotating ring. The outer arc surface of the rotating ring is provided with a toothed groove. Connection holes are opened on the support ring and the side of the reactor body corresponding to the toothed groove. A first motor is mounted on the side of the reactor body. A connecting shaft is mounted on the output shaft of the first motor. A gear is mounted outside the connecting shaft. The gear is located in the connection hole and meshes with the toothed groove. A feed pipe is provided on the reactor cover, and a discharge pipe is provided at the bottom of the reactor body.

[0009] As a further description of the above technical solution:

[0010] Both the first stirring plate and the second stirring plate are arc-shaped, and both the first stirring plate and the second stirring plate rotate along the radial direction of the concave surface.

[0011] As a further description of the above technical solution:

[0012] Both the first and second stirring plates have conical holes. The conical holes are arranged radially along the arc surfaces of the first and second stirring plates. The end of the conical hole near the concave arc surface is the larger opening, and the diameter of the smaller opening is set to 0.5-2mm.

[0013] As a further description of the above technical solution:

[0014] The polymerization reactor also includes a circulation pump connected to the side of the reactor body. A heat exchange tube is connected to the side of the circulation pump. A heating box is installed outside the heat exchange tube. A water inlet pipe is installed below the heating box. A water outlet pipe is installed on the heating box. The portion of the heat exchange tube inside the heating box is spiral-shaped. One end of the heat exchange tube is connected to the reactor body.

[0015] As a further description of the above technical solution:

[0016] The heat exchange tube is fitted with a spiral plate on its inner wall.

[0017] As a further description of the above technical solution:

[0018] Two connecting seats are installed on the inner wall of the heat exchange tube by a fixing rod. A first spring is installed on the right side of the connecting seat. A connecting ball is fixedly connected to the end of the first spring. A connecting rope is fixedly connected to the outside of the two connecting balls. A hollow float is installed outside the connecting rope. The hollow float is located in the interval of the spiral plate.

[0019] As a further description of the above technical solution:

[0020] The heating box is equipped with a shaking mechanism, which includes a drive assembly mounted on the heating box and a connecting clip mounted outside the heat exchange tube. The connecting clip is mounted at the bottom of the drive assembly. The drive assembly includes a second motor and a vertical rod. The vertical rod is mounted on the connecting clip. The second motor is mounted on the heating box. The output shaft of the second motor is fixedly connected to a cam. A contact plate is mounted at the top of the vertical rod and is located below the cam. A sliding sleeve is slidably connected to the outside of the vertical rod and passes through the heating box. A second spring is fitted over the vertical rod and is fixedly connected to the sliding sleeve and the contact plate.

[0021] As a further description of the above technical solution:

[0022] A rotating connecting cylinder is installed at the bottom end of the stirring shaft, and a rotating plate is installed below the rotating connecting cylinder. The lower half of the rotating plate is located inside the discharge pipe.

[0023] As a further description of the above technical solution:

[0024] Two guide ridges are installed on both the front and rear sides of the rotating plate, and a notch is opened on the guide ridge located on the lower side.

[0025] As a further description of the above technical solution:

[0026] The rotating connecting cylinder includes a connecting column fixedly connected to the bottom end of the stirring shaft and a rotating cylinder fixedly connected to the outside of the rotating plate. The connecting column is rotatably connected inside the rotating cylinder. A ratchet is fixedly connected to the outside of the connecting column. A pawl is provided outside the ratchet. A pin is installed outside the pawl inside the rotating cylinder. A third spring is installed outside the pawl and connected to the inside of the rotating cylinder.

[0027] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0028] 1. In this invention, a stirring motor drives a first stirring shaft, and simultaneously, the first motor independently drives the rotating ring containing the second stirring plate through a gear and tooth meshing mechanism. Because the first and second stirring plates have opposite concave orientations, they form a reverse and interlaced composite motion in the radial plane. This motion mode generates highly efficient shearing, tearing, and tumbling effects on the molten material. The reverse and interlaced stirring flow field breaks the laminar boundary of traditional unidirectional stirring, forcing the material to undergo multi-dimensional and intense mixing within the reactor. This greatly promotes the escape of small molecule byproducts and makes the temperature distribution within the reactor more uniform. This significantly improves the polycondensation reaction rate and the uniformity of product viscosity. The "tearing" stirring effect effectively prevents high-viscosity materials from sticking and coking on the reactor wall or stirring paddle, reducing local overheating and thermal degradation of the materials. This not only reduces the content of impurities such as color and acetaldehyde in the final product, but also ensures the uniformity of the product's molecular weight distribution, improving the overall quality of polyester chips. The thorough and efficient stirring shortens the reaction time required to reach the target degree of polymerization, improving production efficiency. At the same time, by avoiding local overheating and ineffective stirring, the overall energy consumption of the system is effectively controlled.

[0029] 2. In this invention, by setting up an external circulating heating water tank and heat exchange tubes, and using a circulating pump to continuously extract the material from the vessel, allowing it to fully exchange heat with hot water in the heat exchange tubes before being injected back into the vessel from the top, this "forced external heat exchange + internal circulation" mode greatly increases the effective heat exchange area per unit time, making the material heated instantly and uniformly, significantly improving the overall heating efficiency and shortening the heating time. The stirring system of this invention provides efficient shearing and tearing mixing in the horizontal direction, while the circulating heating system forcibly pushes the material to flow from bottom to top in the vertical direction. The synergistic effect of horizontal stirring and vertical circulation creates a three-dimensional circulating flow field without dead angles within the reactor, ensuring that all materials receive equal heating and mixing opportunities. This effectively avoids local overheating or uneven reaction. The thorough and uniform heating and stirring greatly promotes surface renewal and mass transfer efficiency of the materials, accelerating the removal of small molecule byproducts in the polycondensation reaction. This not only directly improves the reaction rate and production efficiency but also makes the final product have a more uniform molecular weight distribution, more stable viscosity, and lower color, thereby comprehensively improving the product quality of polyester chips.

[0030] 3. In this invention, the spiral plate inside the heat exchange tube not only guides the material to flow along the length of the tube, but also forces it to generate spiral motion. This motion causes continuous radial position exchange between the high-temperature material near the tube wall and the low-temperature material in the center of the tube, breaking the temperature gradient under laminar flow. At the same time, the spiral plate itself greatly increases the effective contact area between the material and the heat exchange wall. The two work together to significantly improve the overall heat transfer coefficient and temperature uniformity inside the tube. Based on the spiral guidance, this invention innovatively adds a hollow float supported by a spring. Under the impact of the material, the float moves in a high-frequency, small-volume motion within a confined space. The reciprocating motion of the spiral plate causes dynamic changes in the gap between the spiral plate and the material, resulting in periodic compression, shearing, and disturbance of the flowing material. This induces strong turbulence at the microscale, which greatly promotes the micro-mixing of the material and ensures rapid diffusion and uniformity of heat and components at the molecular level. This invention, through the organic combination of "macroscopic spiral guidance" and "microscopic dynamic disturbance," ensures that the material is not only rapidly and uniformly heated during its flow through the heat exchange tube, but also fully mixed, thus guaranteeing that the material entering the reactor has extremely high temperature and compositional uniformity from the source.

[0031] 4. In this invention, the power of the main stirring shaft is extended to the end of the discharge pipe. While driving the stirring plate inside the reactor, the stirring shaft also drives the rotating plate to rotate. The rotating plate utilizes the principle of centrifugal force to effectively "throw" materials that may accumulate at the end of the discharge pipe or on the pipe wall back into the main reaction zone of the reactor. This design completely eliminates the common "dead zone" of the discharge pipe, ensuring that all materials in the reactor participate in the stirring, mixing and reaction process without any omissions. It avoids over-reaction, degradation or carbonization of some materials due to long-term retention in the discharge pipe. If these "dead materials" are mixed into the product in the next discharge, they will seriously affect the quality uniformity and stability of the product batch. The anti-accumulation design of this invention eliminates this hidden danger from the source, ensuring that each batch of polyester chips has consistent high quality. This structure does not require an additional power source and can achieve its function simply through linkage with the main stirring shaft. It is ingeniously designed and highly reliable. At the same time, it effectively prevents the risk of blockage in the discharge pipe, reduces the frequency of equipment downtime for cleaning and maintenance costs, and improves the continuity of production and the overall utilization rate of the equipment. Attached Figure Description

[0032] Figure 1 This is a three-dimensional structural schematic diagram of a polymerization reactor for polyester chip production proposed in this invention;

[0033] Figure 2 This is a schematic diagram of the three-dimensional cross-sectional structure of a polymerization reactor for polyester chip production proposed in this invention.

[0034] Figure 3 This is a schematic diagram of the three-dimensional cross-sectional structure of the rotating ring of a polymerization reactor for polyester chip production proposed in this invention.

[0035] Figure 4 This invention provides a polymerization reactor for polyester chip production. Figure 3 Enlarged structural diagram of section A;

[0036] Figure 5 This is a three-dimensional cross-sectional view of the second stirring plate of a polymerization reactor for polyester chip production proposed in this invention.

[0037] Figure 6 This is a partial three-dimensional cross-sectional view of the heat exchange tube structure of a polymerization reactor for polyester chip production proposed in this invention.

[0038] Figure 7 This invention provides a polymerization reactor for polyester chip production. Figure 6 Enlarged structural diagram of section B;

[0039] Figure 8 This is a three-dimensional cross-sectional view of the heating box of a polymerization reactor for polyester chip production proposed in this invention.

[0040] Figure 9 This is a three-dimensional structural diagram of the shaking mechanism of a polymerization reactor for polyester chip production proposed in this invention;

[0041] Figure 10 This is a schematic diagram of the three-dimensional structure of the rotating plate of a polymerization reactor for polyester chip production proposed in this invention;

[0042] Figure 11 This is a top view schematic diagram of the rotating connecting cylinder structure of a polymerization reactor for polyester chip production proposed in this invention.

[0043] Legend:

[0044] 1. Vessel body; 2. Vessel lid; 3. Stirring motor; 4. Stirring shaft; 5. First stirring plate; 6. Support ring; 7. Rotating ring; 8. Gear groove; 9. Limiting ring; 10. Sealing ring; 11. Connecting hole; 12. Second stirring plate; 13. Gear; 14. Connecting shaft; 15. First motor; 16. Feed pipe; 17. Discharge pipe; 18. Circulating pump; 19. Heat exchange tube; 20. Heating box; 21. Water inlet pipe; 22. Water outlet pipe; 23. Spiral plate; 24. Fixing rod; 25. Connecting seat; 26. First spring; 27. Connecting ball; 28. Connecting rope; 29. ​​Hollow float; 30. Shaking mechanism; 301. Drive assembly; 3011. Vertical rod; 3012. Second motor; 3013. Cam; 3014. Contact plate; 3015. Sliding sleeve; 3016. Second spring; 302. Connecting clip; 31. Rotating connecting cylinder; 311. Connecting column; 312. Rotating cylinder; 313. Ratchet; 314. Pawl; 315. Pin; 316. Third spring; 32. Rotating plate; 33. Guide rib; 34. Tapered hole. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] Please see the appendix Figure 1 -Appendix Figure 11This invention provides a technical solution: a polymerization reactor for polyester chip production, comprising a reactor body 1 and a reactor cover 2. The reactor cover 2 is bolted to the reactor body 1. A stirring motor 3 is mounted on the reactor cover 2. A stirring shaft 4 is fixedly mounted on the output shaft of the stirring motor 3. A first stirring plate 5 is provided outside the stirring shaft 4. A support ring 6 is installed inside the reactor body 1. A rotating ring 7 is rotatably connected inside the support ring 6. A second stirring plate 12 is mounted on the inner arc surface of the rotating ring 7. Two stirring plates 12 are provided on the outer curved surface of the rotating ring 7 in contact with the support ring 6. A sealing ring 10 is provided. A limiting ring 9 is provided inside the support ring 6, located on the upper side of the rotating ring 7. The outer arc surface of the rotating ring 7 is provided with a toothed groove 8. The support ring 6 and the side of the vessel body 1 are provided with connecting holes 11 corresponding to the toothed groove 8. A first motor 15 is installed on the side of the vessel body 1. A connecting shaft 14 is installed on the output shaft of the first motor 15. A gear 13 is installed on the outside of the connecting shaft 14. The gear 13 is located in the connecting hole 11 and meshes with the toothed groove 8. A feed pipe 16 is provided on the vessel cover 2, and a discharge pipe 17 is provided at the bottom of the vessel body 1.

[0047] The stirring motor 3 controls the stirring shaft 4 and the first stirring plate 5 to rotate. At the same time, the first motor 15 controls the gear 13 to rotate through the connecting shaft 14. Since the gear 13 meshes with the tooth groove 8, the gear 13 controls the tooth groove 8, the rotating ring 7 and the second stirring plate 12 to rotate. The first stirring plate 5 and the second stirring plate 12 rotate in opposite directions, which achieves a tearing effect on the raw materials. The stirring process of the raw materials is more thorough, and the contact between the raw materials in the polymerization reaction process is more uniform and sufficient, which reduces the time required for the polymerization reaction and increases the efficiency of polyester chip production.

[0048] Both the first stirring plate 5 and the second stirring plate 12 are arc-shaped, and both the first stirring plate 5 and the second stirring plate 12 rotate along the radial direction of the concave surface.

[0049] Because both the first stirring plate 5 and the second stirring plate 12 are set to be arc-shaped, the arc-shaped plates can support more raw materials when rotating. The raw materials on the surface of the arc-shaped plates are less likely to detach than the raw materials on the surface of the flat plates. Furthermore, due to the stickiness between the raw materials, the first stirring plate 5 and the second stirring plate 12 support more raw materials during rotation, resulting in a more ideal tearing and mixing effect between the raw materials. This ensures sufficient mixing and contact between the raw materials, making the contact between the raw materials more uniform and sufficient during the polymerization reaction, reducing the time required for the polymerization reaction, and increasing the efficiency of polyester chip production.

[0050] The operating parameters of the two counter-rotating stirring plates are as follows: the rotation speed of the first stirring plate 5 is usually set to 50-200 rpm, and the rotation speed of the second stirring plate 12 is set to 30-150 rpm. The speed ratio between the two plates is maintained between 1:0.6 and 1:1.2 to avoid flow field cancellation.

[0051] Both the first stirring plate 5 and the second stirring plate 12 have conical holes 34. The conical holes 34 are arranged in the radial direction along the arc surface of the first stirring plate 5 and the second stirring plate 12. The end of the conical hole 34 near the concave arc surface is the larger opening, and the diameter of the smaller opening end of the conical hole 34 is set to 0.5-2mm.

[0052] More raw materials can enter the conical hole 34, and when the raw materials are pushed by the first stirring plate 5 and the second stirring plate 12, the gas inside the conical hole 34 can be squeezed out. At the same time, since the raw materials have a certain viscosity, they cannot pass through the small-diameter conical hole 34. The first stirring plate 5 and the second stirring plate 12 can normally push the raw materials to rotate. The raw materials entering the conical hole 34 increase the resistance between the raw materials supported by the surfaces of the first stirring plate 5 and the second stirring plate 12 and the stirring plates, making it difficult for the raw materials to detach radially from the rotation direction of the first stirring plate 5 and the second stirring plate 12. More raw materials can be supported to participate in the stirring and mixing process, making the contact between the raw materials in the polymerization reaction process more uniform and sufficient, reducing the time required for the polymerization reaction, and increasing the efficiency of polyester chip production. In addition, water can flow smoothly inside the conical hole 34, which facilitates the rinsing and cleaning of the first stirring plate 5 and the second stirring plate 12.

[0053] The polymerization reactor also includes a circulation pump 18 connected to the side of the reactor body 1. A heat exchange tube 19 is connected to the side of the circulation pump 18. A heating box 20 is installed outside the heat exchange tube 19. A water inlet pipe 21 is installed below the heating box 20. A water outlet pipe 22 is installed on the heating box 20. The part of the heat exchange tube 19 located inside the heating box 20 is spiral-shaped. One end of the heat exchange tube 19 is connected to the reactor body 1.

[0054] The conventional heating method for reactors involves installing heating plates inside the reactor to heat the raw materials inside the reactor body 1. However, the limited contact area between the raw materials and the heating plates results in slow heating efficiency. During the polymerization reaction, the stirring motor 3 and the first motor 15 drive the first stirring plate 5 and the second stirring plate 12 to rotate and mix the raw materials. At this time, the inlet pipe 21 and outlet pipe 22 are connected to a circulating heating water tank. When the heating water tank is running, hot water is introduced into the heating tank 20 from the bottom through the inlet pipe 21. After the heating tank 20 is full, the hot water circulates out of the heating tank 20 through the outlet pipe 22. Simultaneously, the circulating pump 18 operates. The raw material in the reactor body 1 is drawn into the heat exchange tube 19 using a circulating pump 18. The raw material in the heat exchange tube 19 is heated by the heating box 20, which efficiently and fully completes the heating treatment of the raw material. At the same time, the raw material is drawn out from the bottom of the reactor body 1 and injected from the top of the reactor body 1, realizing the circulation of the raw material in the vertical direction within the reactor body 1. The raw material is stirred horizontally by the first stirring plate 5 and the second stirring plate 12, while flowing vertically. The horizontal and vertical stirring makes the stirring process more thorough. Thorough stirring can significantly increase the contact area between materials, promote surface renewal, and improve the reaction efficiency of polyester chips.

[0055] The phased operation process of the polymerization reactor used for polyester chip production is as follows:

[0056] Esterification stage (lower viscosity): mainly using medium-speed stirring (80-120 rpm for the first stirring plate and 60-100 rpm for the second stirring plate), with the circulating pump running at full speed to ensure rapid heating and mixing.

[0057] Polycondensation stage (viscosity increases): reduce stirring speed (50-80 rpm for the first stirring plate, 30-60 rpm for the second stirring plate), reduce the speed of the circulating pump to 50%-70%, and start the shaking mechanism intermittently (running for 1 minute every 10 minutes) to avoid material degradation.

[0058] Control logic: Technical personnel in the relevant field can implement the above-mentioned stage control through PLC programming.

[0059] Spiral plates 23 are installed on the inner wall of heat exchange tube 19.

[0060] The flowing raw material flows along the spiral tube inside the heat exchange tube 19. Since the heat exchange tube 19 is spiral in the heating box 20, the raw material in the heat exchange tube 19 is guided by the spiral plate 23. At the same time, the raw material changes direction to a certain extent due to the spiral shape of the heat exchange tube 19, allowing the raw material in the middle of the heat exchange tube 19 and the raw material attached to the wall to randomly exchange positions, making the mixing and exchange between the raw materials more complete. The positional exchange of the raw material itself can increase the heat exchange efficiency between it and the heat exchange tube 19. In addition, the spiral plate 23 increases the contact area between the heat exchange tube 19 and the raw material. The heat in the heating box 20 is conducted to the raw material through the heat exchange tube 19 and the spiral plate 23. The heat is transferred to the raw material in the heat exchange tube 19 more efficiently, further increasing the heating efficiency of the raw material. The raw material is heated quickly and the mixing efficiency is more complete and thorough, thus ensuring a higher efficiency in the polymerization reaction process of polyester chips.

[0061] Two connecting seats 25 are installed on the inner wall of the heat exchange tube 19 via a fixing rod 24. A first spring 26 is installed on the right side of the connecting seat 25. A connecting ball 27 is fixedly connected to the end of the first spring 26. A connecting rope 28 is fixedly connected to the outside of the two connecting balls 27. A hollow float 29 is installed outside the connecting rope 28. The hollow float 29 is located in the interval of the spiral plate 23.

[0062] When the circulating pump 18 is running, it draws the raw material into the heat exchange tube 19. The raw material then flows back into the vessel body 1. As the raw material flows through the heat exchange tube 19, it impacts the hollow float 29. Due to the spherical structure of the hollow float 29, when impacted by the flowing raw material, the hollow float 29 is positioned in the middle of the heat exchange tube 19. Supported by the elastic force of the first spring 26 and impacted by the raw material, the hollow float 29's swaying is limited to a certain range. The hollow float 29 impacts the raw material as it flows... The elastic force between the first springs 26 causes a slight back-and-forth swaying, which makes the gap between the hollow float 29 and the spiral plate 23 change as the hollow float 29 moves. The continuous change of the gap will squeeze the raw material flowing in the middle of the heat exchange tube 19, so that the raw material is squeezed and guided when flowing in the heat exchange tube 19, making the raw material flow in the heat exchange tube 19 turbulent. The flow rate and direction of the raw material are more variable, and the exchange between the raw materials flowing in the heat exchange tube 19 is more complete, ensuring the heating efficiency and mixing effect of the raw material.

[0063] A swaying mechanism 30 is installed on the heating box 20. The swaying mechanism 30 includes a drive assembly 301 installed on the heating box 20 and a connecting card 302 installed outside the heat exchange tube 19. The connecting card 302 is installed at the bottom of the drive assembly 301. The drive assembly 301 includes a second motor 3012 and a vertical rod 3011. The vertical rod 3011 is installed on the connecting card 302. The second motor 3012 is installed on the heating box 20. The output shaft of the second motor 3012 is fixedly connected to a cam 3013. A contact plate 3014 is installed at the top of the vertical rod 3011. The contact plate 3014 is located below the cam 3013. A sliding sleeve 3015 is slidably connected to the outside of the vertical rod 3011. The sliding sleeve 3015 passes through and is connected to the heating box 20. A second spring 3016 is sleeved on the vertical rod 3011. The second spring 3016 is fixedly connected to the outside of the sliding sleeve 3015 and the contact plate 3014.

[0064] When the circulating pump 18 is working, it draws the raw material into the heat exchange tube 19 to achieve circulation and heating of the raw material. At the same time, it controls the operation of the second motor 3012, which drives the cam 3013 to rotate. When the cam 3013 rotates, it squeezes the contact plate 3014, the vertical rod 3011 and the connecting clip 302 to move downward. When the protruding part of the cam 3013 rotates away from the contact plate 3014, the elastic force of the second spring 3016 drives the vertical rod 3011 and the connecting clip 302 to move upward. The connecting clip 302 causes the heat exchange tube 19 to shake inside the heating box 20, so that the outside of the heat exchange tube 19 can contact the hot water inside the heating box 20 more evenly and fully. At the same time, the raw material inside the heat exchange tube 19 is shaken, which increases the turbulent flow of the raw material inside the heat exchange tube 19, so that the mixing between the raw materials is more thorough and uniform. The heating box 20 heats the raw material in the shaking heat exchange tube 19 more efficiently, and at the same time increases the mixing effect of the raw material in the heat exchange tube 19.

[0065] The core function of the swaying mechanism 30 is not to drive the hollow float 29 to make large-amplitude displacements, but to transmit vibrations to the hollow float 29. In high-viscosity material environments (such as the polycondensation stage, with a viscosity of 2000-5000 mPa·s), the movement of the hollow float 29 is characterized by high-frequency micro-vibrations (amplitude of about 1-3 mm), rather than the large-amplitude swaying in a free-flowing state. This micro-vibration interacts with the viscous resistance of the material itself, generating small pressure fluctuations and velocity gradient changes in a local area around the float, thereby creating a "piercing" disturbance to the originally stable laminar boundary layer.

[0066] Regarding the effectiveness of the hollow float 29, its density is specially designed (0.6-0.9 g / cm³), slightly lower than that of high-viscosity polyester melt (approximately 1.0-1.1 g / cm³), thus placing it near the material surface when static. This induces minute eddies and shear deformations around the hollow float 29, effectively breaking up the agglomeration and deposition tendencies of the material, especially in areas prone to stagnant layers near the reactor wall.

[0067] A rotating connecting cylinder 31 is installed at the bottom of the stirring shaft 4, and a rotating plate 32 is installed below the rotating connecting cylinder 31. The lower half of the rotating plate 32 is located inside the discharge pipe 17.

[0068] When the stirring motor 3 is running, it controls the first stirring plate 5 to rotate through the stirring shaft 4, thereby agitating and mixing the raw materials. At the same time, the stirring shaft 4 drives the rotating plate 32 to rotate. When the rotating plate 32 rotates, it pushes the raw materials in the discharge pipe 17 to rotate. The centrifugal force generated when the raw materials rotate throws the raw materials in the discharge pipe 17 out, so that the raw materials accumulated in the discharge pipe 17 are thrown out into the vessel body 1. This ensures that the raw materials fully participate in the stirring and mixing reaction process, avoids the situation where there are any missed raw materials that cannot participate in the stirring and mixing, and ensures that the mixing of the raw materials is more thorough and complete, without any omissions.

[0069] Two guide ridges 33 are installed on both the front and rear sides of the rotating plate 32, and a notch is opened on the guide ridge 33 located on the lower side.

[0070] The stirring motor 3 controls the rotation of the first stirring plate 5 through the stirring shaft 4 to agitate and mix the raw materials. At the same time, the stirring shaft 4 drives the rotating plate 32 to rotate. When the rotating plate 32 rotates, it pushes the raw materials in the discharge pipe 17 to rotate. The centrifugal force generated by the rotating raw materials throws them out in all directions. The arc-shaped setting of the guide protrusion 33 can block and guide the process of the raw materials being thrown out centrifugally. The guide protrusion 33 also blocks the raw materials falling from above, slowing down the falling of the raw materials into the discharge pipe 17. The raw materials in the discharge pipe 17 can be continuously thrown out. The raw materials are drawn upward and flow upward through the gap of the lower guide protrusion 33, ensuring that a lot of raw materials do not accumulate in the discharge pipe 17 and cannot participate in the stirring. This ensures that the stirring and mixing is more thorough and uniform, and the polymerization reaction efficiency is higher.

[0071] The rotating connecting cylinder 31 includes a connecting column 311 fixedly connected to the bottom end of the stirring shaft 4 and a rotating cylinder 312 fixedly connected to the outside of the rotating plate 32. The connecting column 311 is rotatably connected inside the rotating cylinder 312. A ratchet 313 is fixedly connected to the outside of the connecting column 311. A pawl 314 is provided outside the ratchet 313. A pin 315 installed inside the rotating cylinder 312 is provided outside the pawl 314. A third spring 316 connected inside the rotating cylinder 312 is installed outside the pawl 314.

[0072] The stirring motor 3 controls the rotation of the first stirring plate 5 via the stirring shaft 4. The first stirring plate 5 agitates and mixes the raw materials. At this time, the pawl 314 abuts against the surface of the ratchet 313. The connecting column 311 controls the rotation of the rotating cylinder 312 and the rotating plate 32 via the ratchet 313 and the pawl 314. When the rotating plate 32 rotates, it pushes the raw materials in the discharge pipe 17 to rotate. After the agitation, mixing and reaction of the raw materials are completed, the raw materials need to be discharged through the discharge pipe 17. If the rotating plate 32 continues to rotate, it will throw out the raw materials in the discharge pipe 17, affecting the raw materials. In terms of discharge efficiency, at this time, the stirring motor 3 controls the first stirring plate 5 to reverse, the ratchet 313 rotates and squeezes the pawl 314 to rotate around the pin 315. At this time, the third spring 316 is compressed, and the connecting column 311 rotates but cannot drive the rotating cylinder 312 and the rotating plate 32 to rotate, so that the raw material can flow out smoothly through the discharge pipe 17, ensuring the smooth progress of the discharge process. In this scheme, the forward rotation stirring process can throw the raw material out, and the rotating plate 32 reverses to discharge the raw material normally, so as to ensure the production efficiency of polyester chip polymerization.

[0073] Example 1:

[0074] In the esterification reaction stage, efficient mixing and shearing effects are achieved under optimized parameters.

[0075] 1. Experimental conditions:

[0076] Reactants: Purified terephthalic acid (PTA) and ethylene glycol (EG) are used as raw materials in a molar ratio of 1:1.15.

[0077] Reaction equipment: The reaction vessel described in this invention is used.

[0078] Reaction stage: Esterification reaction stage (material viscosity is low, about 50-200 mPa·s).

[0079] 2. Key parameter settings:

[0080] First stirring plate (5) speed: set to 120 rpm (clockwise rotation).

[0081] Second stirring plate (12) speed: set to 100 rpm (counterclockwise rotation).

[0082] Speed ​​ratio: The speed ratio of the second stirring plate to the first stirring plate is 1:0.83, which falls within the recommended range of 1:0.6 to 1:1.2.

[0083] Other conditions: The temperature inside the reactor is controlled at 250°C, and the pressure is atmospheric pressure.

[0084] 3. Implementation process and effect verification:

[0085] When the reactor is operated under the specified parameters, the following can be observed:

[0086] Flow field visualization verification: Through the sight glass of the vessel or computational fluid dynamics (CFD) simulation, it can be seen that the flow fields generated by the first stirring plate (5) and the second stirring plate (12) do not cancel each other out due to their opposite concave surfaces and opposite rotation, but instead form staggered convection and shear zones. The material is "held up" in the concave surface of the arc-shaped stirring plate and is strongly stretched and torn in the opposite direction of motion, realizing the claimed "tearing" stirring.

[0087] Supporting data: Under these stirring conditions, the esterification reaction water removal time was reduced by approximately 15% compared to traditional unidirectional stirring (single impeller, 100 rpm). Analysis of samples taken after the reaction showed that the temperature difference between different points in the reactor was less than 2°C, demonstrating the uniformity of heating and mixing. This example verifies that within the recommended parameter range, an effective shear flow field can be formed, significantly improving mixing efficiency.

[0088] Example 2:

[0089] During the polycondensation reaction stage, parameter adjustments in the high viscosity stage are offset by the anti-flow field.

[0090] 1. Experimental conditions:

[0091] Reactants: The prepolymer after esterification enters the polycondensation stage (the viscosity of the material increases significantly, about 2000-5000 mPa·s).

[0092] Reaction equipment: Same as in Example 1.

[0093] 2. Key parameter adjustments:

[0094] First stirring plate (5) speed: In order to avoid excessive shear force under high viscosity leading to material degradation, the speed is adjusted to 60 rpm (counterclockwise rotation).

[0095] Second stirring plate (12) speed: adjust to 50 rpm (clockwise rotation).

[0096] Speed ​​ratio: The speed ratio of the second stirring plate to the first stirring plate is 1:0.83, which remains unchanged and is still within the optimization range.

[0097] Other conditions: The temperature inside the vessel is raised to 275°C, and the pressure is gradually evacuated to below 100Pa.

[0098] 3. Implementation process and effect verification:

[0099] Cooperative operation: During this stage, the speed of the circulating pump (18) is synchronously reduced to 60% of the rated power to reduce the strong shearing of high viscosity materials; the swaying mechanism (30) is started intermittently (running for 2 minutes every 15 minutes) to help break the flow boundary layer.

[0100] Supporting data: Under this parameter combination, the stirring motor operated smoothly without any abnormal torque fluctuations caused by flow field cancellation. The final polyester chips exhibited an intrinsic viscosity (IV) deviation of less than 0.01 dL / g and a narrow molecular weight distribution (PDI), indicating uniform material mixing and sufficient reaction throughout the polycondensation process, effectively avoiding localized overheating or insufficient reaction. This example demonstrates that adjusting the rotation speed within the recommended parameter range at different reaction stages can maintain effective shear mixing while adapting to changes in material properties and avoiding flow field cancellation.

[0101] Example 3:

[0102] 1. Experimental objective:

[0103] The test verifies whether the conical hole 34 on the stirring plate of the present invention can work stably for a long time without clogging in a high viscosity environment (viscosity of about 2000 mPa·s) simulating the polyester polycondensation stage.

[0104] 2. Experimental conditions and methods:

[0105] Test material: A polyethylene glycol (PEG) aqueous solution with a viscosity of approximately 2000±100 mPa·s was prepared to simulate the material characteristics of the polyester polycondensation stage.

[0106] Experimental equipment: The reaction vessel described in this invention was used. The focus was on observing the first stirring plate 5 and the second stirring plate 12, which are equipped with conical holes 34.

[0107] Tapered hole parameters: The small diameter of the tapered hole 34 is set to 1.0 mm (take the midpoint value).

[0108] Operating parameters:

[0109] First stirring plate 5 rotation speed: 70 rpm (clockwise);

[0110] Second stirring plate 12 rotation speed: 60 rpm (counterclockwise);

[0111] Reactor temperature: 50°C (to maintain stable material viscosity);

[0112] Experiment duration: 120 minutes of continuous operation to simulate the reaction time of one batch.

[0113] 3. Experimental Results and Data Recording:

[0114] During and after the experiment, the state of the conical hole was observed and recorded. Key data are shown in the table below:

[0115]

[0116] Post-experiment inspection: After stopping operation and discharging the material, the mixing plate was rinsed with a high-pressure water gun. The inspection revealed that there was no residual material in any of the cone holes 34, and the rinsing water flowed smoothly, confirming that there were no permanent blockages or dead spots where material could accumulate.

[0117] 4. Analysis of Experimental Conclusions:

[0118] Anti-clogging mechanism verification: Experimental data shows that at a high viscosity of 2000 mPa·s, the conical orifice 34 did not become clogged. The key reason lies in the dynamic cleaning effect: the conical orifice 34 of this invention is formed on a high-speed rotating arc-shaped stirring plate. When the stirring plate rotates, the material is continuously "thrown" through the conical orifice under the action of centrifugal force and shear force. In particular, the large opening design of the conical orifice facilitates the entry of material, while the small opening generates a strong shearing effect under high-speed motion, effectively preventing the retention and accumulation of viscous materials. This dynamic design based on motion is fundamentally different from static filter orifices.

[0119] Furthermore, during the continuous operation for 120 minutes, the torque value of the drive motor and the system pressure difference remained stable, with fluctuations within ±5%, which is within the normal operating range of the equipment. This indicates that the flow channel remained unobstructed and no additional resistance was generated due to the conical orifice issue. Visual observation further confirmed the unobstructed state of the conical orifice.

[0120] Conclusion: This experimental example fully demonstrates that under the working conditions described in this invention (stirring plate movement + specific conical hole structure), even when facing high-viscosity materials of 2000 mPa·s, the conical hole 34 can effectively avoid clogging, and its design is reasonable and feasible.

[0121] Working principle and usage:

[0122] The raw materials required for the polymerization reaction of polyester chips are injected into the reactor body 1 through the feed pipe 16. The stirring motor 3 and the first motor 15 are controlled to run. The stirring motor 3 controls the stirring shaft 4 and the first stirring plate 5 to rotate. At the same time, the first motor 15 controls the gear 13 to rotate through the connecting shaft 14. Since the gear 13 meshes with the tooth groove 8, the gear 13 controls the tooth groove 8, the rotating ring 7 and the second stirring plate 12 to rotate. The first stirring plate 5 and the second stirring plate 12 both rotate in the radial direction of their concave direction. Since the concave directions of the first stirring plate 5 and the second stirring plate 12 are opposite, the first stirring plate 5 and the second stirring plate 12 rotate in opposite directions, which achieves a tearing effect on the raw materials and makes the mixing process of the raw materials more thorough.

[0123] At the same time as the stirring begins, the circulating pump 18 and the second motor 3012 are started, and the inlet pipe 21 and outlet pipe 22 are connected to the circulating heating water tank. When the heating water tank is running, hot water is introduced into the heating tank 20 from the bottom through the inlet pipe 21. After the heating tank 20 is full, the hot water flows out of the heating tank 20 through the outlet pipe 22. At the same time as the circulating pump 18 is working, the raw material in the vessel 1 is drawn into the heat exchange tube 19. As the raw material flows in the heat exchange tube 19, it impacts the hollow float 29. Due to the spherical structure of the hollow float 29, when impacted by the flowing raw material, the hollow float 29 is positioned in the middle of the heat exchange tube 19. The flowing raw material flows along the spiral tube inside the heat exchange tube 19. Since the heat exchange tube 19 is spiral-shaped within the heating chamber 20, the raw material in the heat exchange tube 19 is guided by the spiral plate 23 while undergoing a certain degree of reversal. This allows for a cyclical exchange of position between the raw material in the middle of the heat exchange tube 19 and the raw material attached to the wall, resulting in more thorough mixing and exchange. Furthermore, the repositioning of the raw material itself increases the heat exchange efficiency with the heat exchange tube 19. The spiral plate 23 also increases the contact area between the heat exchange tube 19 and the raw material, further increasing the heating efficiency of the raw material. The hollow float 29, supported by the elastic force of the first spring 26, is confined to a certain range. Within a certain range, the hollow float 29 oscillates back and forth slightly due to the impact of the flowing raw material and the elastic force between it and the first spring 26. This causes the gap between the hollow float 29 and the spiral plate 23 to change as the hollow float 29 moves. The continuous change in the gap compresses the raw material flowing in the middle of the heat exchange tube 19, causing the raw material to be squeezed and guided as it flows in the heat exchange tube 19, resulting in a turbulent flow. The second motor 3012 drives the cam 3013 to rotate. When the cam 3013 rotates, it compresses the contact plate 3014, the vertical rod 3011, and the connecting clip 302, causing them to move downwards. When the protruding part of the cam 3013 moves away from the contact plate... When 3014 rotates, the elastic force of the second spring 3016 drives the vertical rod 3011 and the connecting card 302 to move upward. The connecting card 302 drives the heat exchange tube 19 to shake inside the heating box 20, so that the outside of the heat exchange tube 19 can contact the hot water inside the heating box 20 more evenly and fully. The raw material inside the heat exchange tube 19 is shaken, increasing the turbulent flow of the raw material inside the heat exchange tube 19, so as to achieve more thorough and uniform mixing between the raw materials. The raw material is drawn by the circulating pump 18, heated and circulated into the pump body through the heat exchange tube 19, so as to realize the up and down flow of the raw material in the vessel 1. The horizontal stirring and vertical flow of the raw material are combined to make the mixing of the raw material more thorough.

[0124] While the stirring shaft 4 rotates, the rotating cylinder 312 and the rotating plate 32 are controlled to rotate through the connecting column 311, ratchet 313 and pawl 314. When the rotating plate 32 rotates, it pushes the raw material in the discharge pipe 17 to rotate. The centrifugal force generated during the rotation throws the raw material in the discharge pipe 17 out. The guide convex strip 33 guides the direction of the raw material thrown out by the centrifugal force and blocks the raw material falling from above to prevent the raw material from falling back into the discharge pipe 17. The raw material thrown out by the centrifugal force is circulated and stirred by the first stirring plate 5, the second stirring plate 12 and the circulating pump 18 to fully realize the mixing treatment between the raw materials.

[0125] After the raw material mixing and polymerization reaction is completed, the circulating pump 18 is stopped and the stirring motor 3 is reversed. The stirring motor 3 controls the stirring shaft 4 and the first stirring plate 5 to stir the raw material in the reactor body 1. At the same time, the ratchet 313 squeezes the pawl 314 to rotate. At this time, the third spring 316 is compressed, and the connecting column 311 cannot drive the rotating cylinder 312 and the rotating plate 32 to rotate, so that the raw material can flow out smoothly through the discharge pipe 17.

[0126] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A polymerization reactor for producing polyester chips, comprising a reactor body (1) and a reactor lid (2), characterized in that, The lid (2) is bolted to the body (1). A stirring motor (3) is mounted on the lid (2). A stirring shaft (4) is fixedly mounted on the output shaft of the stirring motor (3). A first stirring plate (5) is provided outside the stirring shaft (4). A support ring (6) is installed inside the body (1). A rotating ring (7) is rotatably connected inside the support ring (6). A second stirring plate (12) is installed on the inner arc surface of the rotating ring (7). Two sealing rings (10) are provided on the curved contact part between the outer surface of the rotating ring (7) and the support ring (6). A sealing ring (10) is provided inside the support ring (6) located on the rotating ring (7). The upper limit ring (9) is provided with a toothed groove (8) on the outer arc surface of the rotating ring (7). The support ring (6) and the side of the vessel body (1) are provided with a connecting hole (11) corresponding to the toothed groove (8). The side of the vessel body (1) is equipped with a first motor (15). The output shaft of the first motor (15) is equipped with a connecting shaft (14). A gear (13) is installed on the outside of the connecting shaft (14). The gear (13) is located in the connecting hole (11) and meshes with the toothed groove (8). The vessel cover (2) is provided with a feed pipe (16). The vessel body (1) is provided with a discharge pipe (17). The first stirring plate (5) and the second stirring plate (12) are both arc-shaped, and the first stirring plate (5) and the second stirring plate (12) rotate along the radial direction of the concave surface; the concave directions of the first stirring plate (5) and the second stirring plate (12) are opposite, and the first stirring plate (5) and the second stirring plate (12) rotate alternately in opposite directions; Both the first stirring plate (5) and the second stirring plate (12) are provided with conical holes (34). The conical holes (34) are arranged in the radial direction along the arc surface of the first stirring plate (5) and the second stirring plate (12). The end of the conical hole (34) near the concave arc surface is the large opening, and the diameter of the small opening end of the conical hole (34) is set to 0.5-2mm.

2. The polymerization reactor for polyester chip production according to claim 1, characterized in that, The polymerization reactor also includes a circulation pump (18) connected to the side of the reactor body (1). A heat exchange tube (19) is connected to the side of the circulation pump (18). A heating box (20) is installed outside the heat exchange tube (19). A water inlet pipe (21) is installed below the heating box (20). A water outlet pipe (22) is installed on the heating box (20). The part of the heat exchange tube (19) located inside the heating box (20) is spiral. One end of the heat exchange tube (19) is connected to the reactor body (1).

3. The polymerization reactor for polyester chip production according to claim 2, characterized in that, The inner wall of the heat exchange tube (19) is fitted with a spiral plate (23).

4. The polymerization reactor for polyester chip production according to claim 3, characterized in that, The inner wall of the heat exchange tube (19) is equipped with two connecting seats (25) by a fixing rod (24). A first spring (26) is installed on the right side of the connecting seat (25). A connecting ball (27) is fixedly connected to the end of the first spring (26). A connecting rope (28) is fixedly connected to the outside of the two connecting balls (27). A hollow float (29) is installed outside the connecting rope (28). The hollow float (29) is located in the interval of the spiral plate (23).

5. The polymerization reactor for polyester chip production according to claim 4, characterized in that, A swaying mechanism (30) is installed on the heating box (20). The swaying mechanism (30) includes a drive assembly (301) installed on the heating box (20) and a connecting clip (302) installed outside the heat exchange tube (19). The connecting clip (302) is installed at the bottom of the drive assembly (301). The drive assembly (301) includes a second motor (3012) and a vertical rod (3011). The vertical rod (3011) is installed on the connecting clip (302). The second motor (3012) is installed on the heating box (20). The output shaft of the second motor (3012) is fixedly connected to a cam (3013). A contact plate (3014) is installed at the top of the vertical rod (3011). The contact plate (3014) is located under the cam (3013). A sliding sleeve (3015) is slidably connected to the outside of the vertical rod (3011). The sliding sleeve (3015) is connected through the heating box (20). A second spring (3016) is provided on the outer sleeve of the vertical rod (3011). The second spring (3016) is fixedly connected to the outside of the sliding sleeve (3015) and the contact plate (3014).

6. The polymerization reactor for polyester chip production according to claim 1, characterized in that, A rotating connecting cylinder (31) is installed at the bottom end of the stirring shaft (4), and a rotating plate (32) is installed below the rotating connecting cylinder (31). The lower half of the rotating plate (32) is located inside the discharge pipe (17).

7. A polymerization reactor for polyester chip production according to claim 6, characterized in that, Two guide ridges (33) are installed on both the front and rear sides of the rotating plate (32), and a notch is provided on the guide ridge (33) located on the lower side.

8. The polymerization reactor for polyester chip production according to claim 7, characterized in that, The rotating connecting cylinder (31) includes a connecting column (311) fixedly connected to the bottom end of the stirring shaft (4) and a rotating cylinder (312) fixedly connected to the outside of the rotating plate (32). The connecting column (311) is rotatably connected inside the rotating cylinder (312). A ratchet (313) is fixedly connected to the outside of the connecting column (311). A pawl (314) is provided outside the ratchet (313). A pin (315) installed inside the rotating cylinder (312) is provided outside the pawl (314). A third spring (316) connected inside the rotating cylinder (312) is installed outside the pawl (314).

Images