Production device of poly (1, 4-cyclohexanedimethanol terephthalate)

Abstract

The embodiment of the invention provides a production device of poly (1, 4-cyclohexylenedimethylene terephthalate), and relates to the technical field of high polymer materials. The production device of the poly (1, 4-cyclohexanedimethanol terephthalate) comprises: an esterification reactor; the first polycondensation reactor is communicated with the esterification reactor; the second polycondensation reactor comprises a reaction cylinder and at least two baffling assemblies, the reaction cylinder is communicated with the first polycondensation reactor, the baffling assemblies are arranged in the reaction cylinder, and the baffling assemblies are sequentially arranged at intervals in the axial direction of the reaction cylinder; the next baffling assembly in two adjacent baffling assemblies is used for receiving the prepolymer flowing down from the previous baffling assembly, and the baffling assemblies are used for guiding and heating the prepolymer. The baffling assembly can directly and uniformly heat the prepolymer, so that the heat transfer effect is improved, the heat transfer area is increased, the heating time is prolonged, and the reaction efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high polymer materials, and particularly relates to a production device of poly(1,4-cyclohexanedimethylene terephthalate). BACKGROUND

[0002] Poly(1,4-cyclohexanedimethylene terephthalate) is a high-performance polyester material, which has excellent heat resistance, mechanical strength, chemical stability and low moisture absorption, and is widely used in the fields of electronic appliances, automobile manufacturing, industrial equipment and the like. The poly(1,4-cyclohexanedimethylene terephthalate) can be obtained by mixing terephthalic acid and 1,4-cyclohexanedimethanol, and sequentially performing esterification and polycondensation reactions in an esterification reactor and a polycondensation reactor.

[0003] In the related art, a heating element is arranged outside the polycondensation reactor, the polycondensation reactor is heated by the heating element, heat is transmitted to the inner layer material through the polycondensation reactor wall, and the inner layer material is stirred by a stirring element in the polycondensation reactor, so that the material is heated and polycondensation reaction occurs in the polycondensation reactor.

[0004] However, when the polycondensation reaction is performed, the heating element heats the polycondensation reactor as a whole from the outer layer to the inner layer, the heat transfer effect is poor, and the reaction efficiency is low. SUMMARY

[0005] The embodiment of the present application provides a production device of poly(1,4-cyclohexanedimethylene terephthalate), which is used to overcome the problem that the heating element in the prior art heats the second polycondensation reactor as a whole from the outer layer to the inner layer, the heat transfer effect is poor, and the reaction efficiency is low.

[0006] The embodiment of the present application provides a production device of poly(1,4-cyclohexanedimethylene terephthalate), which comprises:

[0007] an esterification reactor, which is used for esterification of terephthalic acid and 1,4-cyclohexanedimethanol to obtain an esterification product;

[0008] a first polycondensation reactor, which is in communication with the esterification reactor, and is used for receiving the esterification product and performing a prepolymerization reaction on the esterification product to obtain a prepolymer;

[0009] a second polycondensation reactor for receiving the prepolymer and subjecting the prepolymer to a polycondensation reaction to obtain a final polymer, the second polycondensation reactor comprising a reaction cylinder and at least two baffle assemblies, the reaction cylinder being in communication with the first polycondensation reactor, the baffle assemblies being arranged in the reaction cylinder, the baffle assemblies being arranged in sequence and spaced apart along the reaction cylinder in an axial direction, a next baffle assembly of two adjacent baffle assemblies being arranged to receive the prepolymer flowing from a previous baffle assembly, the baffle assembly being arranged to guide and heat the prepolymer.

[0010] In one possible implementation, the baffle assembly comprises a baffle plate and a heating element connected to the baffle plate, the heating element being arranged to heat the baffle plate, the baffle plate being connected to an inner wall of the reaction cylinder, and two adjacent baffle plates being arranged in a staggered manner, each layer of the baffle plates having a downcomer in communication with an adjacent baffle plate.

[0011] In one possible implementation, the baffle plate has an opposite baffle surface and a backflow surface, the baffle surface being provided with a plurality of pits arranged in an array, the backflow surface being connected to the heating element, a plurality of flow guide fins being arranged in a spaced apart manner on an edge of the baffle surface, the plurality of flow guide fins being connected to the baffle plate to form the downcomer.

[0012] In one possible implementation, the baffle assembly is connected to the reaction cylinder in an inclined manner, and an inclination angle of the baffle assembly is greater than or equal to 3°.

[0013] In one possible implementation, the second polycondensation reactor further comprises at least one distributor arranged in the reaction cylinder and in communication with the first polycondensation reactor, the distributor being arranged to uniformly deliver the prepolymer generated in the first polycondensation reactor to the baffle plate.

[0014] In one possible implementation, the distributor comprises a distribution disc arranged above the baffle plate in the topmost layer, the distribution disc being uniformly provided with a plurality of openings, and the openings being aligned with the baffle plate in the topmost layer.

[0015] In one possible implementation, the first polycondensation reactor comprises a reaction tank and a spiral partition plate arranged in the reaction tank, the spiral partition plate in the outermost layer and an inner wall of the reaction tank together defining a flow guide channel, the reaction tank being provided with an esterification product feeding port in communication with the esterification reactor, a port of the flow guide channel being in communication with the esterification product feeding port, and the flow guide channel extending in a spiral shape along the reaction tank in an axial direction.

[0016] In a possible implementation, the inner part of the reaction tank forms a reaction chamber, which is in communication with another port of the flow guide channel, and a stirring member is arranged in the reaction chamber.

[0017] In a possible implementation, two vacuum units are further included, and the first polycondensation reactor and the second polycondensation reactor are respectively in communication with one of the vacuum units through corresponding gas-phase pipelines.

[0018] In a possible implementation, a slurry mixing tank, a granulation unit, and a post-processing unit are further included; the slurry mixing tank is used for uniformly stirring and mixing the terephthalic acid and the 1,4-cyclohexanedimethanol, and is in communication with an inlet of the esterification reactor;

[0019] The granulation unit includes a cutting granulator, a drying machine, and a crystallizer in sequence, the cutting granulator is in communication with the second polycondensation reactor, and the granulation unit is used for cutting and drying the final polymer output by the second polycondensation reactor; the post-processing unit includes a post-processing bin and a dedusting tower in sequence, the post-processing bin is in communication with the crystallizer, and the post-processing unit is used for increasing viscosity of the cut granules output by the granulation unit.

[0020] The production device for poly(1,4-cyclohexanedimethylene terephthalate) provided in the embodiments of the present application comprises at least two baffling components arranged in the reaction cylinder of the second polycondensation reactor, the reaction cylinder is in communication with the first polycondensation reactor, the reaction cylinder can receive the prepolymer output by the first polycondensation reactor, and the baffling components are arranged in the axial direction of the reaction cylinder. In addition, the next baffling component can receive the prepolymer flowing down from the previous baffling component, so that the final polymer transported into the second polycondensation reactor can flow down through the baffling components in sequence. The baffling components have a heating function, can directly and uniformly heat the prepolymer flowing through the baffling components, improve the heat transfer effect, increase the heat transfer area and heating time, and thus improve the reaction efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0021] The accompanying drawings, which are incorporated into and form a part of the specification, illustrate one embodiment consistent with the present application and, together with the description, serve to explain the principles of the application.

[0022] Figure 1 A structural schematic diagram of the production device for poly(1,4-cyclohexanedimethylene terephthalate) provided in the present application is shown in the figure.

[0023] Figure 2 A structural schematic diagram of the production device for poly(1,4-cyclohexanedimethylene terephthalate) provided in the present application is shown in the figure. Figure 1 A detailed enlarged view of position A in the production device for poly(1,4-cyclohexanedimethylene terephthalate) provided in the present application is shown in the figure.

[0024] Figure 3 A structural schematic diagram of the production device for poly(1,4-cyclohexanedimethylene terephthalate) provided in the present application is shown in the figure.Figure 2 A side view of a liquid distributor and a baffle in a production device of poly(1,4-cyclohexylenedimethylene terephthalate) provided in the present application;

[0025] Figure 4 For Figure 1 A structural schematic diagram of a baffle in a production device of poly(1,4-cyclohexylenedimethylene terephthalate) provided in the present application;

[0026] Figure 5 For Figure 1 A main perspective view of a first polycondensation reactor in a production device of poly(1,4-cyclohexylenedimethylene terephthalate) provided in the present application.

[0027] BRIEF DESCRIPTION OF DRAWINGS

[0028] 100 - slurry mixing tank;

[0029] 200 - esterification reactor;

[0030] 300 - first polycondensation reactor; 310 - reaction tank; 311 - esterification product feed port; 312 - reaction chamber; 313 - first by-product outlet; 320 - flow guide channel; 330 - spiral partition; 340 - heating jacket;

[0031] 400 - second polycondensation reactor; 410 - reaction cylinder; 411 - second by-product outlet; 420 - baffle assembly; 421 - baffle plate; 4211 - downcomer; 4212 - backflow surface; 4213 - pit; 4214 - flow guide fin; 430 - distributor; 431 - distribution disc; 432 - opening; 433 - discharge pipe;

[0032] 500 - granulation unit; 510 - granulator; 520 - dryer; 530 - crystallizer;

[0033] 600 - vacuum unit; 610 - gas phase pipeline;

[0034] 700 - pneumatic conveying unit; 710 - granulated material bin; 720 - transmitter;

[0035] 800 - post-treatment unit; 810 - post-treatment material bin; 820 - impurity removal tower;

[0036] 900 - tail gas treatment device.

[0037] The specific embodiments of the present application have been shown in the above-described drawings, and will be described in more detail hereinafter. These drawings and written descriptions are not intended to limit the scope of the concept of the present application by any means, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0038] The exemplary embodiments will be described in detail herein with reference to the attached drawings. In the following description, the same numbers are used to indicate the same or similar components. The following exemplary embodiments are not meant to represent the only embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with some aspects of the present application as detailed in the appended claims.

[0039] The terms "first", "second", "third", etc. (if any) in the description, claims, and drawings of the present application are used to distinguish similar objects, and do not necessarily indicate a particular order or sequence. It should be understood that the data thus used can be interchanged, where appropriate, so that the embodiments of the present application described herein can be carried out in other sequences than those illustrated or described herein.

[0040] Secondly, it should be noted that in the description of the present application, the terms "inner", "outer", "first direction", "second direction", etc. indicating the direction or positional relationship are based on the direction or positional relationship shown in the drawings, which is merely for the convenience of description, and does not indicate or imply that the device or member must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0041] In addition, it should be noted that in the description of the present application, unless otherwise explicitly specified and limited, the terms "connected", "connected" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication between the two components inside. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0042] As shown in the background, in the related art, a heating member is arranged outside the polycondensation reactor, the polycondensation reactor is heated by the heating member, the heat is transmitted to the inner layer material through the polycondensation reactor wall, and the inner layer material is stirred by the stirring member in the polycondensation reactor, so that the material is heated and polycondensation reaction occurs in the polycondensation reactor.

[0043] However, when polycondensation reaction is carried out, the heating member heats the polycondensation reactor as a whole from the outside to the inner layer, the heat transfer effect is poor, and the reaction efficiency is low.

[0044] To solve the above technical problems, the embodiment of the present application provides a production device of poly(1,4-cyclohexylenedimethylene terephthalate), which comprises: an esterification reactor, the esterification reactor is used for performing esterification reaction on terephthalic acid and 1,4-cyclohexylenedimethylene to obtain esterification product; a first polycondensation reactor, the first polycondensation reactor is communicated with the esterification reactor, the first polycondensation reactor is used for receiving the esterification product and performing prepolymerization reaction on the esterification product to obtain prepolymer; and a second polycondensation reactor, the second polycondensation reactor is used for receiving the prepolymer and performing polycondensation reaction on the prepolymer to obtain final polymer, the second polycondensation reactor comprises a reaction cylinder and at least two baffle assemblies, the reaction cylinder is communicated with the first polycondensation reactor, the baffle assemblies are arranged in the reaction cylinder, the baffle assemblies are sequentially and spacedly arranged along the axial direction of the reaction cylinder, a next baffle assembly in the adjacent two baffle assemblies is used for receiving the prepolymer flowed from a previous baffle assembly, and the baffle assemblies are used for guiding and heating the prepolymer. The baffle assemblies can directly and uniformly heat the prepolymer, the heat transfer effect is improved, the heat transfer area and heating time are increased, and therefore the reaction efficiency is improved.

[0045] The technical solutions of the present application and how the technical solutions of the present application solve the above technical problems will be described in detail in specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes can not be described again in some embodiments. The embodiments of the present application will be described below with reference to the drawings.

[0046] The embodiment of the present application provides a production device of poly(1,4-cyclohexylenedimethylene terephthalate), which combines Figure 1 and Figure 2 As shown in the figure, the production device comprises: an esterification reactor 200, the esterification reactor 200 is used for performing esterification reaction on terephthalic acid and 1,4-cyclohexylenedimethylene to obtain esterification product.

[0047] A first polycondensation reactor 300, the first polycondensation reactor 300 is communicated with the esterification reactor 200, the first polycondensation reactor 300 is used for receiving the esterification product and performing prepolymerization reaction on the esterification product to obtain prepolymer.

[0048] A second polycondensation reactor 400, the second polycondensation reactor 400 is used for receiving the prepolymer and performing polycondensation reaction on the prepolymer to obtain final polymer, the second polycondensation reactor 400 comprises a reaction cylinder 410 and at least two baffle assemblies 420, the reaction cylinder 410 is communicated with the first polycondensation reactor 300, the baffle assemblies 420 are arranged in the reaction cylinder 410, the baffle assemblies 420 are sequentially and spacedly arranged along the axial direction of the reaction cylinder 410, a next baffle assembly 420 in the adjacent two baffle assemblies 420 is used for receiving the prepolymer flowed from a previous baffle assembly 420, and the baffle assemblies 420 are used for guiding and heating the prepolymer.

[0049] It can be understood that the process for preparing poly-1,4-cyclohexane dimethylene terephthalate includes esterification and polycondensation reactions. The esterification reaction is carried out by mixing terephthalic acid and 1,4-cyclohexane dimethanol with a catalyst to generate esterification products, which are then subjected to polycondensation reaction to obtain poly-1,4-cyclohexane dimethylene terephthalate. Throughout the preparation process, sufficient heating is required to facilitate the movement of the equilibrium towards the polycondensation direction, increase the viscosity and obtain poly-1,4-cyclohexane dimethylene terephthalate with high degree of polymerization.

[0050] Specifically, at least two baffle assemblies 420 are arranged in the reaction cylinder 410 of the second polycondensation reactor 400, the reaction cylinder 410 is in communication with the first polycondensation reactor 300, the reaction cylinder 410 is capable of receiving the prepolymer generated in the first polycondensation reactor 300, the baffle assemblies 420 are arranged axially along the reaction cylinder 410, and the next baffle assembly 420 is capable of receiving the prepolymer flowing down from the previous baffle assembly 420, so that the final polymer transported into the second polycondensation reactor can flow down the prepolymer in sequence through the baffle assemblies. The baffle assembly 420 has a heating function and can directly and uniformly heat the prepolymer flowing through the baffle assembly 420, thereby improving the heat transfer effect, increasing the heat transfer area and heating time, and thus improving the reaction efficiency.

[0051] In one possible implementation, as shown in Figure 2 The baffle assembly 420 includes a baffle plate 421 and a heating element connected to the baffle plate 421, the heating element is used to heat the baffle plate 421, the baffle plate 421 is connected to the inner wall of the reaction cylinder 410, and the adjacent two baffle plates 421 are arranged in a staggered manner, and each layer of baffle plate 421 has a downcomer 4211 which is in communication with the adjacent baffle plate 421.

[0052] As shown in Figure 2 The adjacent two baffle plates 421 are arranged axially along the reaction cylinder 410, and the adjacent two baffle plates 421 are arranged in a staggered manner in a stepped shape, the downcomer 4211 of the baffle plate 421 in the upper layer is in communication with the baffle plate 421 in the lower layer, so that the prepolymer transported into the reaction cylinder 410 can flow down in sequence through the baffle plate 421, and fully react during the flow process to form the final polymer.

[0053] The heating element can be a heating plate which is in close contact with the baffle plate 421 to fully heat the baffle plate 421 and improve the heat transfer effect. Of course, the heating element can also be a serpentine heating coil which is in close contact with the surface of the baffle plate 421, that is, the heating element is not limited as long as it can be in close contact with the baffle plate 421 for heating and enhancing the heat transfer effect to fully react the prepolymer.

[0054] Further, in combination with Figure 2 andFigure 4 As shown in the figure, the baffle plate 421 has oppositely arranged baffle surface and backflow surface 4212, the baffle surface is provided with a plurality of pits 4213 arranged in an array, the backflow surface 4212 is connected with the heating element, and a plurality of flow guide fins 4214 are arranged at intervals on the edge of the baffle surface, and the plurality of flow guide fins 4214 are connected with the baffle plate 421 to form a downcomer 4211.

[0055] Specifically, referring to Figure 2 and Figure 4 As shown in the figure, the baffle surface and the backflow surface 4212 are oppositely arranged, the baffle surface is provided with a plurality of pits 4213, the plurality of pits 4213 can be arranged in an array, and the baffle surface of the baffle plate 421 at the top layer is arranged opposite to the distributor 430 (to be introduced below), and the heating element is arranged on the backflow surface 4212.

[0056] Among them, the prepolymer transported into the reaction cylinder 410 can flow down layer by layer through the baffle surface, and the plurality of pits 4213 can not only increase the residence time of the prepolymer, but also increase the turbulence of the prepolymer, and the heat transfer coefficient is significantly improved, so that the output heat of the heating element is effectively transmitted to the prepolymer, and the reaction efficiency is high.

[0057] In addition, as shown in Figure 4 The edge of the baffle plate 421 is provided with a plurality of flow guide fins 4214, the plurality of flow guide fins 4214 extend towards the baffle surface and protrude from the baffle surface, the plurality of flow guide fins 4214 are arranged at intervals along the width direction of the baffle surface, the flow guide fin 4214 is connected with the baffle surface to form a downcomer 4211, and the downcomer 4211 composed of a plurality of flow guide fins 4214 can disperse the flowing down prepolymer, avoid converging to the next baffle plate 421, and affect the heat transfer effect.

[0058] And the downcomer 4211 is located at the lowest position in each baffle plate 421, the prepolymer on the baffle plate 421 can flow to the lowest position through the downcomer 4211, and then flow smoothly to the next baffle plate 421, the flow state of the prepolymer is always in a flat flow state, ensuring that the properties of the prepolymer are uniform and stable, so as to occur polycondensation reaction and improve the reaction efficiency.

[0059] Among them, in a possible implementation, in combination with Figure 1 and Figure 2 As shown in the figure, the baffle assembly 420 is connected with the reaction cylinder 410 at an inclination, and the inclination angle of the baffle assembly 420 is greater than or equal to 3°.

[0060] Specifically, in combination with Figure 1 and Figure 2As shown, the baffle plates 421 in the baffle assembly 420 are inclinedly connected with the inner wall of the reaction cylinder 410, and the baffle plates 421 extend along the axial direction of the reaction cylinder 410 from top to bottom in an inclined manner, and the inclination angle of the baffle plates 421 is greater than or equal to 3°, so that the prepolymer transported into the reaction cylinder 410 can flow from the highest point of the baffle plates 421 to the lowest point in sequence, and then flow to the next baffle plate 421, that is, the prepolymer can flow down layer by layer along the baffle plates 421 of the top layer from top to bottom without the need of additional power driving.

[0061] In one possible implementation, with reference to Figure 2 As shown, the second polycondensation reactor 400 further comprises at least one distributor 430, the distributor 430 is arranged in the reaction cylinder 410, and the distributor 430 is in communication with the first polycondensation reactor 300, and the distributor 430 is used to uniformly transport the prepolymer generated in the first polycondensation reactor 300 to the baffle plates 421.

[0062] As shown in Figure 2 The reaction cylinder 410 further comprises at least one distributor 430, the baffle plates 421 can be arranged correspondingly with the distributors 430, the input end of the distributor 430 is in communication with the first polycondensation reactor 300, and the output end of the distributor 430 corresponds to the baffle surface of the baffle plates 421, so that the prepolymer generated in the first polycondensation reactor 300 can be uniformly transported to the baffle surface of the baffle plates 421 through the distributor 430, avoiding the accumulation of the prepolymer on the baffle plates 421, not only affecting the heat transfer effect, but also needing additional flow pushing tools, increasing the cost.

[0063] Further, in combination with Figure 2 and Figure 3 As shown, the distributor 430 comprises a distribution disc 431, the distribution disc 431 is arranged above the topmost baffle plate 421, and a plurality of openings 432 are uniformly arranged on the distribution disc 431, and the openings 432 are aligned with the topmost baffle plate 421.

[0064] Specifically, in combination with Figure 2 and Figure 3 As shown, the distribution disc 431 is located above the topmost baffle plate 421, and a plurality of openings 432 are uniformly arranged on the surface of the distribution disc 431 facing the topmost baffle plate 421, and the other surface of the distribution disc 431 is in vertical communication with a downcomer 433, and the downcomer 433 is in communication with the first polycondensation reactor 300 through a pipeline.

[0065] Prepolymer flows into the distribution disc 431 through the downcomer 433, and then uniformly disperses onto the baffle surface of the baffle plates 421 through the openings 432 of the distribution disc 431, so that the prepolymer is more uniformly distributed, the heat transfer efficiency is enhanced, and the reaction efficiency is improved.

[0066] In one possible implementation, combining Figure 1 and Figure 5 As shown, the first polycondensation reactor 300 includes a reaction vessel 310 and a spiral baffle 330 disposed inside the reaction vessel 310. The outermost spiral baffle 330 and the inner wall of the reaction vessel 310 enclose a flow channel 320. An esterification feed inlet 311 communicating with the esterification reactor 200 is provided on the side wall of the reaction vessel 310. The port of the flow channel 320 is connected to the esterification feed inlet 311. The flow channel 320 extends spirally along the axial direction of the reaction vessel 310.

[0067] Specifically, in combination Figure 1 and Figure 5 As shown, the reaction vessel 310 is provided with an esterification inlet 311, which is located on the side of the reaction vessel 310 and near the top. The esterification inlet 311 is used to transport esterification into the reaction vessel 310.

[0068] Among them, combined Figure 5 As shown, the outermost spiral baffle 330 forms a flow channel 320 with the inner wall of the reaction vessel 310. The port of the flow channel 320 is connected to the ester feed inlet 311, ensuring that the ester can flow smoothly into the flow channel 320 after being transported to the reaction vessel 310. The ester can spirally flow from the ester feed inlet 311 toward the inside of the reaction vessel 310 along the extension direction of the spiral baffle 330, and generate spin under the action of inertia, pushing the ester in the flow channel 320 to continuously flow downward, avoiding back mixing, and achieving uniform mixing without the need for external power. While ensuring the mixing of the ester, it reduces energy consumption during the reaction process.

[0069] Furthermore, refer to Figure 5 As shown, a portion of the space inside the reaction vessel 310 forms a reaction chamber 312, which is connected to the other end of the flow channel 320. A stirring element is installed inside the reaction chamber 312.

[0070] Specifically, such as Figure 5 As shown, the reaction chamber 312 is connected to the other end of the flow channel 320, away from the ester feed inlet 311. That is, one end of the flow channel 320 is connected to the ester feed inlet 311, and the other end is connected to the reaction chamber 312. The ester flows into the reaction chamber 312 through the flow channel 320. Furthermore, a first by-product outlet 313 is provided at the top of the reaction vessel 310, through which the gas generated during the reaction can be output. Figure 1 As shown, the first by-product outlet 313 can be connected to the vacuum unit 600 (described below) to regulate the vacuum level inside the reaction vessel 310.

[0071] It can be understood that the reaction tank 310 is provided with a prepolymer outlet, and the reaction chamber 312 communicates with the prepolymer outlet. The reaction chamber 312 is provided with a stirring piece, which can be a down-pumping stirring piece. The stirring piece can not only fully stir and mix the materials in the reaction tank 310 to avoid stratification, but also facilitate the output of the formed prepolymer through the prepolymer outlet.

[0072] It should be noted that a heating piece can also be provided on the reaction tank 310. The heating piece can be a heating coil and a heating jacket 340. That is, the heating jacket 340 can be provided on the outer peripheral wall of the reaction tank 310, and the heating coil can extend into the reaction chamber 312 through the prepolymer outlet. The heating piece is used to heat the lactate in the reaction tank 310 to perform the polycondensation reaction and form the prepolymer.

[0073] In one possible implementation, as shown in Figure 1 two vacuum units 600 are further included. The first polycondensation reactor 300 and the second polycondensation reactor 400 respectively communicate with one of the vacuum units 600 through corresponding gas phase pipelines 610.

[0074] Specifically, as shown in Figure 1 the two vacuum units 600 are a prepolymerization vacuum unit and a polycondensation vacuum unit. The top of the first polycondensation reactor 300 is provided with a first by-product outlet 313, and the top of the second polycondensation reactor 400 is provided with a second by-product outlet 411.

[0075] The prepolymerization vacuum unit communicates with the first by-product outlet 313 through the gas phase pipeline 610, and is used to regulate the vacuum degree in the first polycondensation reactor 300. The polycondensation vacuum unit communicates with the second by-product outlet 411 through the gas phase pipeline 610, and is used to regulate the vacuum degree in the second polycondensation reactor 400.

[0076] It can be understood that small molecule by-products are generated during the prepolymerization reaction. The small molecule by-products are sucked away by the prepolymerization vacuum unit through the first by-product outlet 313, thereby indirectly providing a vacuum negative pressure environment for the first polycondensation reactor 300.

[0077] In addition, the prepolymerization vacuum unit can regulate the vacuum degree in the first polycondensation reactor 300, so that the lactate received in the first polycondensation reactor 300 is heated and stirred in a vacuum environment, thereby promoting the balance to move in the polycondensation direction, increasing the viscosity to obtain the prepolymer.

[0078] Similarly, the macromolecular by-products generated during the polycondensation reaction are discharged through the second by-product outlet 411, and the polycondensation vacuum unit is further used to increase the vacuum degree in the second polycondensation reactor 400. In a high vacuum environment, deep devolatilization is realized to obtain a final polymer with a higher degree of polymerization.

[0079] In one possible implementation, such as Figure 1 As shown, it also includes a slurry mixing tank 100, a granulation unit 500, and a post-processing unit 800.

[0080] The slurry mixing tank 100 is used to stir and mix terephthalic acid and 1,4-cyclohexanediethanol evenly. The slurry mixing tank 100 is connected to the inlet of the esterification reactor 200.

[0081] The granulation unit 500 includes a pelletizer 510, a dryer 520 and a crystallizer 530 connected in sequence. The pelletizer 510 is connected to the second polycondensation reactor 400. The granulation unit 500 is used to pelletize and dry the final polymer produced by the second polycondensation reactor 400.

[0082] The post-processing unit 800 includes a post-processing hopper 810 and a purification tower 820 connected in sequence. The post-processing hopper 810 is connected to the crystallizer 530. The post-processing unit 800 is used to thicken the pellets output from the granulation unit 500.

[0083] Specifically, refer to Figure 1 As shown, the slurry mixing tank 100 is equipped with a preparation tank, which can mix terephthalic acid and 1,4-cyclohexanediethanol in a certain proportion to obtain a mixed slurry. The esterification reactor 200 is connected to the slurry mixing tank 100, and the mixed slurry can be transported to the esterification reactor 200. In the esterification reactor 200, the esterification reaction is carried out by heating and stirring to obtain the esterified product.

[0084] The slurry mixing tank 100 is also equipped with an air outlet, which is connected to the tail gas treatment device 900. When terephthalic acid and 1,4-cyclohexanediethanol are mixed evenly in the mixing tank, the generated tail gas can be transported to the tail gas treatment device 900 through the air outlet, so as to avoid the tail gas from flowing directly into the air and causing air pollution.

[0085] Combination Figure 1 As shown, the pelletizer 510 is connected to the second polycondensation reactor 400. A rotary cutter is installed inside the pelletizer 510. The final polymer produced in the second polycondensation reactor 400 can be transported to the pelletizer 510, and the rotary cutter of the pelletizer 510 is used to pelletize the final polymer.

[0086] Understandably, the pellets are fed from the pelletizer 510 through the dryer 520 into the crystallizer 530. The dryer 520 first dries the pellets before they enter the crystallizer 530, where hot nitrogen is introduced to crystallize the surface of the pellets, thereby preventing the pellets from sticking together at high temperatures.

[0087] It should be noted that the final polymer produced in the second polycondensation reactor 400 is cooled in water free of impurities and is extruded from the grinding head of the pelletizer 510 while being cut into elliptical particles by the rotating cutter.

[0088] As shown in Figure 1 The production device further comprises an air conveying unit 700, which comprises a pellet bin 710 and a sender 720. The pellet bin 710 is in communication with the crystallizer 530, and the cut pellets after the crystallization process can be collected and stored in the pellet bin 710. One end of the sender 720 is in communication with the pellet bin 710, and the other end is in communication with the post-processing unit 800. The cut pellets are blown into the post-processing unit 800 by introducing gas into the sender 720, and subsequent viscosity increase is performed.

[0089] It can be understood that, in order to enhance the degree of polymerization of the final polymer, the crystallized cut pellets after the crystallization process in the crystallizer 530 can be transported to the post-processing bin 810 for viscosity increase of the cut pellets by the post-processing bin 810.

[0090] As shown in Figure 1 The post-processing bin 810 is in communication with the sender 720. The post-processing bin 810 is provided with a gas inlet and a gas outlet. The gas inlet is used to transport heated nitrogen, and the gas outlet is in communication with the impurity removal tower 820. The cut pellets enter the post-processing bin 810 and further undergo polycondensation reaction under the heating of nitrogen, so as to obtain the shaped poly-l,4-cyclohexanedimethylene terephthalate product.

[0091] It should be noted that the by-products produced in the polycondensation reaction are transported into the impurity removal tower 820 by the nitrogen through the gas outlet. The adsorbent in the impurity removal tower 820 adsorbs the by-products and other impurities in the nitrogen, so that the nitrogen is purified, and the subsequent nitrogen can be recycled.

[0092] Finally, it should be noted that other embodiments of the present application will occur to those skilled in the art upon consideration of the specification and practice of the application disclosed herein. The present application is intended to cover any variations, uses or adaptive changes of the present application following the general principles of the present application and including known or customary technical means in the art not disclosed by the present application, and is not limited to the precise structures described above and shown in the drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A production apparatus for poly(1,4-cyclohexanediethanol) terephthalate, characterized in that, include: Esterification reactor (200), said esterification reactor (200) is used to esterify terephthalic acid and 1,4-cyclohexanediethanol to obtain esterified products; A first polycondensation reactor (300) is connected to the esterification reactor (200). The first polycondensation reactor (300) is used to receive the esterified material and to prepolymerize the esterified material to obtain a prepolymer. The second polycondensation reactor (400) is used to receive the prepolymer and perform a polycondensation reaction on the prepolymer to obtain the final polymer. The second polycondensation reactor (400) includes a reaction cylinder (410) and at least two baffle components (420). The reaction cylinder (410) is connected to the first polycondensation reactor (300). The baffle components (420) are disposed inside the reaction cylinder (410). The baffle components (420) are arranged sequentially at intervals along the axial direction of the reaction cylinder (410). In two adjacent baffle components (420), the next baffle component (420) is used to receive the prepolymer flowing down from the previous baffle component (420). The baffle component (420) is used to guide and heat the prepolymer.

2. The production apparatus for poly(1,4-cyclohexanediethanol) terephthalate according to claim 1, characterized in that, The baffle assembly (420) includes a baffle plate (421) and a heating element connected to the baffle plate (421). The heating element is used to heat the baffle plate (421). The baffle plate (421) is connected to the inner wall of the reaction cylinder (410), and two adjacent baffle plates (421) are staggered. Each layer of the baffle plate (421) has a downcomer (4211), and the downcomer (4211) is connected to the adjacent baffle plate (421).

3. The production apparatus for poly(1,4-cyclohexanediethanol) terephthalate according to claim 2, characterized in that, The baffle plate (421) has a baffle surface and a backflow surface (4212) arranged opposite to each other. The baffle surface is provided with a plurality of pits (4213) arranged in an array. The backflow surface (4212) is connected to the heating element. A plurality of guide fins (4214) are arranged at intervals on the edge of the baffle surface. The plurality of guide fins (4214) are connected to the baffle plate (421) to form the liquid discharge port (4211).

4. The production apparatus for poly(1,4-cyclohexanediethanol) terephthalate according to claim 1, characterized in that, The baffle assembly (420) is inclinedly connected to the reaction cylinder (410), and the inclination angle of the baffle assembly (420) is greater than or equal to 3°.

5. The production apparatus for poly(1,4-cyclohexanediethanol) terephthalate according to claim 2, characterized in that, The second polycondensation reactor (400) further includes at least one distributor (430), which is disposed inside the reaction cylinder (410) and is connected to the first polycondensation reactor (300). The distributor (430) is used to uniformly transport the prepolymer generated in the first polycondensation reactor (300) to the baffle plate (421).

6. The apparatus for producing poly(1,4-cyclohexanediethanol) terephthalate according to claim 5, characterized in that, The distributor (430) includes a distribution disk (431) which is disposed above the top baffle plate (421). The distribution disk (431) is provided with a plurality of openings (432) which are evenly arranged on the distribution disk (431) and are aligned with the top baffle plate (421).

7. The production apparatus for poly(1,4-cyclohexanediethanol) terephthalate according to claim 1, characterized in that, The first polycondensation reactor (300) includes a reaction vessel (310) and a spiral baffle (330) disposed inside the reaction vessel (310). The outermost spiral baffle (330) and the inner wall of the reaction vessel (310) enclose a flow channel (320). An esterification inlet (311) communicating with the esterification reactor (200) is provided on the side wall of the reaction vessel (310). The port of the flow channel (320) is connected to the esterification inlet (311). The flow channel (320) extends spirally along the axial direction of the reaction vessel (310).

8. The apparatus for producing poly(1,4-cyclohexanediethanol) terephthalate according to claim 7, characterized in that, The reaction vessel (310) has a portion of its space forming a reaction chamber (312), which is connected to the other end of the flow channel (320). A stirring element is provided inside the reaction chamber (312).

9. The apparatus for producing poly(1,4-cyclohexanediethanol) terephthalate according to any one of claims 1-8, characterized in that, It also includes two vacuum units (600), the first polycondensation reactor (300) and the second polycondensation reactor (400) being connected to one of the vacuum units (600) via corresponding gas phase pipes (610).

10. The apparatus for producing poly(1,4-cyclohexanediethanol) terephthalate according to any one of claims 1-8, characterized in that, It also includes a slurry mixing tank (100), a granulation unit (500), and a post-processing unit (800). The slurry mixing tank (100) is used to stir and mix the terephthalic acid and the 1,4-cyclohexanediethanol evenly, and the slurry mixing tank (100) is connected to the inlet of the esterification reactor (200); The granulation unit (500) includes a pelletizer (510), a dryer (520) and a crystallizer (530) connected in sequence. The pelletizer (510) is connected to the second polycondensation reactor (400). The granulation unit (500) is used to pelletize and dry the final polymer produced by the second polycondensation reactor (400). The post-processing unit (800) includes a post-processing hopper (810) and a cleaning tower (820) connected in sequence. The post-processing hopper (810) is connected to the crystallizer (530). The post-processing unit (800) is used to thicken the pellets output by the granulation unit (500).

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