Continuous production plant for polyesters

Abstract

This application provides a continuous polyester production apparatus, relating to the field of polyester synthesis technology. The continuous polyester production apparatus includes an esterification reactor, a pre-polymerization reactor, and a final polymerization reactor. The pre-polymerization reactor includes a first pre-polymerization reactor and a second pre-polymerization reactor. The second pre-polymerization reactor includes a second reactor body, a drive unit, a first stirring assembly, a second stirring assembly, and a third stirring assembly. The second reactor body has a second inlet and a second outlet. The drive unit is inserted into the second reactor body. The first, second, and third stirring assemblies are all mounted on the drive unit and are arranged sequentially at intervals along the direction from the second inlet to the second outlet. The final polymerization reactor is connected to the second outlet. This arrangement improves heat and mass transfer under high temperature and high viscosity conditions, enhances the continuous production capacity of the apparatus, and ensures stable molecular weight distribution and performance of the product.

Description

Technical Field

[0001] This application relates to the field of polyester synthesis technology, and more particularly to a continuous polyester production apparatus. Background Technology

[0002] Poly(1,4-cyclohexanediethanol) terephthalate (PCT) and its copolyesters exhibit good heat resistance, low moisture absorption, and chemical resistance. The synthesis of the polyester mainly involves two steps: esterification and polycondensation. The reactants are esterified to form esterified products, which are then subjected to polycondensation to form polycondensates reaching the target degree of polymerization.

[0003] In related technologies, patent application number 202010428516.1 discloses a reaction system and method for producing high molecular weight polyester through continuous melt polycondensation. The reaction system includes an esterification reactor, a pre-polycondensation reactor, and a final polycondensation reactor connected in sequence. The reactants are transported to the esterification reactor for esterification to obtain esterified products. The esterified products are then passed into the pre-polycondensation reactor and the final polycondensation reactor for polycondensation to obtain polycondensed products.

[0004] However, the high viscosity of reactants during the polycondensation reaction stage leads to a decrease in the mass transfer efficiency of the pre-polycondensation reactor, resulting in a wide molecular weight distribution and unstable performance of the product. Summary of the Invention

[0005] This application provides a continuous polyester production apparatus to overcome the problems in the prior art where the reactant viscosity is high during the polycondensation reaction stage, the mass transfer efficiency of the pre-polycondensation reactor decreases, resulting in a wide molecular weight distribution and unstable performance of the product.

[0006] This application provides a continuous polyester production apparatus, including an esterification reactor.

[0007] A prepolymerization reactor, comprising a first prepolymerization reactor and a second prepolymerization reactor, wherein the second prepolymerization reactor comprises a second reactor body, a drive unit, a first stirring assembly, a second stirring assembly, and a third stirring assembly, the second reactor body having a second inlet and a second outlet, the second inlet being connected to the first prepolymerization reactor, the first prepolymerization reactor being connected to the esterification reactor, the drive unit being inserted into the second reactor body, and the first stirring assembly, the second stirring assembly, and the third stirring assembly being disposed on the drive unit and arranged sequentially at intervals along the direction from the second inlet to the second outlet.

[0008] A final polycondensation reactor, which is connected to the second discharge port.

[0009] In one possible implementation, the first stirring assembly is a cage-type disc with multiple through holes.

[0010] The second stirring assembly includes multiple disc groups, which are spaced apart along the extension direction of the drive member. Each disc group includes a connector and at least two discs, which are disposed on the drive member. At least two discs are connected by the connector.

[0011] The third stirring component comprises multiple discs, which are spaced apart along the extension direction of the driving member, and each disc has a groove.

[0012] In one possible implementation, a scraper is also included, one end of which is fixed to the second reactor body, and the other end of which extends toward the drive member, and the scraper is located between two adjacent third stirring components, wherein the scraper located between two adjacent third stirring components is pointed.

[0013] In one possible implementation, the tip of the scraper is located on one side of the drive member, the other end of the scraper is located on the other side of the drive member and connected to the second reactor body, the scraper portion covers the drive member, and there is a gap between the scraper and the covered portion of the drive member.

[0014] In one possible implementation, the drive unit includes a first spindle and a second spindle, both of which are located on the axis of the second reactor body. The first spindle is inserted at one end of the second reactor body, and the second spindle is inserted at the other end of the second reactor body. The first stirring assembly is disposed on the first spindle, and the second stirring assembly and the third stirring assembly are disposed on the second spindle.

[0015] In one possible implementation, the first prepolymerization reactor has a first inlet and a first outlet. The first prepolymerization reactor includes a first cylinder and a second cylinder disposed outside the first cylinder. The first cylinder has a reaction chamber, and an annular cavity is formed between the second cylinder and the first cylinder. An overflow port is provided on the first cylinder for connecting the reaction chamber and the annular cavity. The first inlet is for connecting the reaction chamber and the esterification reactor, and the first outlet is for connecting the annular cavity and the second inlet.

[0016] In one possible implementation, the ratio of the diameter of the second cylinder to the diameter of the first cylinder is greater than or equal to 1.5 and less than or equal to 2.2.

[0017] The second cylindrical body includes a straight cylindrical section and a conical cylindrical section connected to the straight cylindrical section. The diameter of the conical cylindrical section gradually decreases in the direction away from the straight cylindrical section. The ratio of the diameter of the straight cylindrical section to the diameter of the conical cylindrical section is greater than or equal to 1.2 and less than or equal to 2.

[0018] In one possible implementation, the final polycondensation reactor includes a horizontal cylindrical body, a drive shaft, a plurality of cleaning discs, and a plurality of cleaning blade assemblies. The drive shaft is inserted into the horizontal cylindrical body along its extension direction. The plurality of cleaning discs are disposed on the drive shaft and are spaced apart along the extension direction of the drive shaft. The plurality of cleaning blade assemblies are disposed at the edges of the cleaning discs and are used to conform to the inner wall of the horizontal cylindrical body to clean the horizontal cylindrical body and the cleaning discs.

[0019] In one possible implementation, two drive shafts are arranged in parallel. The cleaning disc includes a disc body and a hub. The hub is located at the center of the disc body and is sleeved on the drive shaft. The cleaning discs on the two drive shafts are arranged alternately. The two drive shafts are configured to rotate synchronously in opposite directions or in the same direction.

[0020] In one possible implementation, the cleaning disc is a round disc, a willow leaf disc, or a crescent-shaped shovel disc.

[0021] In one possible implementation, a plurality of nozzles are also included, each disposed within both the second prepolymerization reactor and the final polymerization reactor. The nozzles are spaced apart along the axial direction of the second prepolymerization reactor and the final polymerization reactor, and are used to spray diol vapor toward the inner walls of the second prepolymerization reactor and the final polymerization reactor for cleaning.

[0022] In one possible implementation, the esterification reactor includes a first esterification reactor and a second esterification reactor connected in sequence, the second esterification reactor being connected to the first feed inlet.

[0023] The second esterification reactor includes a reaction vessel body and multiple agitators. The reaction vessel body has multiple chambers, which are arranged sequentially along the extension direction of the reaction vessel body. Each chamber is provided with a corresponding agitator.

[0024] This application provides a continuous polyester production apparatus. By setting up an esterification reactor, a second prepolymerization reactor connected to the esterification reactor and having a second inlet and a second outlet, and a final polymerization reactor connected to the second outlet, and by sequentially arranging a first stirring component, a second stirring component, and a third stirring component at intervals along the material flow direction on the drive unit in the second prepolymerization reactor, the esterified material can be continuously propelled and fully mixed in the prepolymerization stage, improving the heat and mass transfer effect under high temperature and high viscosity conditions, thereby improving the continuous production capacity, reaction stability, raw material utilization rate, and ensuring the molecular weight distribution and performance stability of the product. Attached Figure Description

[0025] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0026] Figure 1 A schematic diagram of the continuous polyester production apparatus provided in this application;

[0027] Figure 2 for Figure 1 A schematic diagram of the structure of the second prepolymerization reactor in the continuous polyester production unit provided in the document;

[0028] Figure 3 for Figure 2 A side view of the second prepolymerization reactor provided in the image;

[0029] Figure 4 for Figure 2 A schematic diagram of the structure of the third stirring assembly in the second prepolymerization reactor provided in the diagram;

[0030] Figure 5 for Figure 1 A schematic diagram of the structure of the first prepolymerization reactor in the continuous polyester production unit provided in the document;

[0031] Figure 6 for Figure 1 A schematic diagram of the final polycondensation reactor in a continuous polyester production unit provided in the document.

[0032] Figure 7 for Figure 6 The diagram shows the structure of the cleaning disc in the final polycondensation reactor provided in the image.

[0033] Explanation of reference numerals in the attached figures:

[0034] 100 - Esterification reactor; 110 - First esterification reactor; 120 - Second esterification reactor; 121 - Reactor body; 122 - Stirring component;

[0035] 200 - Prepolymerization reactor;

[0036] 210 - First prepolymerization reactor; 211 - First feed inlet; 212 - First discharge outlet; 213 - First cylinder; 2131 - Overflow outlet; 214 - Second cylinder; 2141 - Straight cylinder section; 2142 - Conical cylinder section; 215 - Reaction chamber; 216 - Annular cavity;

[0037] 220 - Second prepolymerization reactor; 221 - Second reactor body; 2211 - Second feed inlet; 2212 - Second discharge outlet; 222 - Drive component; 2221 - First main shaft; 2222 - Second main shaft; 223 - First stirring assembly; 2231 - Through hole; 224 - Second stirring assembly; 2241 - Connector; 2242 - Disc; 225 - Third stirring assembly; 2251 - Groove; 226 - Scraper; 227 - Gap;

[0038] 300 - Final polycondensation reactor; 310 - Horizontal cylindrical body; 320 - Drive shaft; 330 - Cleaning disc; 331 - Disc body; 332 - Hub; 340 - Cleaning blade assembly;

[0039] 400-nozzle;

[0040] 500 - Slurry preparation structure;

[0041] 600-Pelletizing Unit;

[0042] 700-Viscosity sensor.

[0043] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0044] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application.

[0045] The terms "first," "second," "third," etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein.

[0046] Secondly, it should be noted that in the description of this 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. This is only for the convenience of description and does not indicate or imply that the device or component must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this application.

[0047] Furthermore, it should be noted that, in the description of this application, unless otherwise expressly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0048] The preparation of polyethylene terephthalate (PET) 1,4-cyclohexanediethanol ester and its copolyesters generally adopts a combination of esterification and polycondensation processes. First, the monomers are converted into oligomers in the esterification equipment, and then small molecules are further removed and the molecular weight is increased in the pre-polycondensation and final polycondensation equipment to obtain polyester products that meet the requirements of use.

[0049] In related technologies, an esterification reactor combined with a series of polycondensation devices is typically used to achieve the reaction requirements and obtain polyester products. Specifically, after the reactants complete the esterification reaction in the esterification reactor, the materials are transferred to a subsequent polycondensation reactor, where they continue to devolatilize and promote the polymerization reaction under heating and depressurization conditions, thereby gradually forming high molecular weight polyester.

[0050] However, during the polycondensation reaction, the viscosity of the material continuously increases, and the heat and mass transfer conditions inside traditional equipment deteriorate, easily leading to problems such as incomplete local reactions, unstable removal of volatile components, and uneven material residence. Especially during the transition from the pre-polymerization stage to the polycondensation reaction stage, if the stirring and conveying conditions cannot be effectively matched with changes in material characteristics, the utilization rate of unreacted monomers will be limited, resulting in low heat and mass transfer efficiency. This further makes it difficult to stably control the molecular weight distribution and batch performance consistency of the product, and affects the continuous operation capability and overall production efficiency of the equipment.

[0051] Therefore, how to balance continuous conveying, stable reaction progress, and ensuring heat and mass transfer efficiency in the polyester production process has become a key issue that urgently needs to be addressed for this type of equipment.

[0052] To address the aforementioned problems, this application provides a continuous polyester production apparatus, comprising: an esterification reactor, a pre-polymerization reactor, and a final polymerization reactor. The pre-polymerization reactor includes a first pre-polymerization reactor and a second pre-polymerization reactor. The second pre-polymerization reactor includes a second reactor body, a drive unit, a first stirring assembly, a second stirring assembly, and a third stirring assembly. The second reactor body has a second inlet and a second outlet. The second inlet is connected to the first pre-polymerization reactor, and the first pre-polymerization reactor is connected to the esterification reactor. The drive unit is inserted into the second reactor body. The first, second, and third stirring assemblies are all mounted on the drive unit and are arranged sequentially at intervals along the direction from the second inlet to the second outlet. The final polymerization reactor is connected to the second outlet.

[0053] By setting up an esterification reactor, a second prepolymerization reactor connected to the esterification reactor and having a second inlet and a second outlet, and a final polymerization reactor connected to the second outlet, and by sequentially and intermittently arranging a first stirring component, a second stirring component, and a third stirring component on the drive unit in the second prepolymerization reactor along the material flow direction, the esterified material can be continuously propelled and fully mixed in the prepolymerization stage, improving the heat and mass transfer effect under high temperature and high viscosity conditions, thereby improving the continuous production capacity, reaction stability, raw material utilization rate, and ensuring the molecular weight distribution and performance stability of the product.

[0054] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0055] This application provides a continuous polyester production apparatus, referring to... Figure 1 As shown, it includes: esterification reactor 100, prepolymerization reactor 200 and final polymerization reactor 300.

[0056] The prepolymerization reactor 200 includes a first prepolymerization reactor 210 and a second prepolymerization reactor 220. The second prepolymerization reactor 220 includes a second reactor body 221, a drive unit 222, a first stirring assembly 223, a second stirring assembly 224, and a third stirring assembly 225. The second reactor body 221 has a second inlet 2211 and a second outlet 2212. The second inlet 2211 is connected to the first prepolymerization reactor 210, and the first prepolymerization reactor 210 is connected to the esterification reactor 100. The drive unit 222 is inserted into the second reactor body 221. The first stirring assembly 223, the second stirring assembly 224, and the third stirring assembly 225 are all disposed on the drive unit 222 and are arranged sequentially at intervals along the direction from the second inlet 2211 to the second outlet 2212.

[0057] The final polycondensation reactor 300 is connected to the second discharge port 2212.

[0058] The esterification reactor 100 is a reaction device used to complete the esterification reaction of polyester raw materials and form materials suitable for subsequent polycondensation. The esterification reactor 100 can be connected to the pre-polycondensation reactor 200 as a feed source for the subsequent pre-polycondensation reactor 200.

[0059] The prepolymerization reactor 200 is an intermediate reaction device used to further polymerize the material from the esterification reactor 100. It is located after the esterification reactor 100 and connected to the final polymerization reactor 300, and serves as a transition from the front-end reaction to the back-end reaction.

[0060] like Figure 1 As shown, the prepolymerization reactor 200 includes a first prepolymerization reactor 210 and a second prepolymerization reactor 220. The second inlet 2211 of the second prepolymerization reactor 220 is connected to the first prepolymerization reactor 210. The first prepolymerization reactor 210 is connected to the esterification reactor 100. The second outlet 2212 is connected to the final polymerization reactor 300 to ensure continuous transition of materials between different reaction stages.

[0061] Specifically, the second prepolymerization reactor 220 is used to receive the esterified material and to mix and transport it under the combined action of the drive unit 222 and the stirring assembly, so that the material reaches the state required for further reaction before entering the final polymerization reactor 300.

[0062] The second reactor body 221 refers to the main body structure that constitutes the main containment space of the second prepolymerization reactor 220. It is used to form a cavity for material reaction and flow, and to provide an installation base for the drive unit 222 and the stirring assembly.

[0063] The second reactor body 221 is provided with a second inlet 2211 and a second outlet 2212. The second inlet 2211 is used to communicate with the esterification reactor 100 to receive the esterified products formed in the esterification reactor 100, and the second outlet 2212 is connected to the final polycondensation reactor 300 to output the pre-polycondensed material. The two are distributed along the material flow direction to form a channel.

[0064] The driving component 222 refers to the transmission component installed inside the second reactor body 221 and used to drive the stirring assembly. The driving component 222 is used to drive the material to regenerate and propel it axially during the pre-condensation stage, thereby cooperating with the reaction process to achieve mixing and conveying.

[0065] like Figure 2 As shown, the drive unit 222 can be inserted into the second reactor body 221 and arranged along its extension direction to transmit power to the interior of the body.

[0066] The first stirring component 223, the second stirring component 224, and the third stirring component 225 all refer to stirring or conveying components installed on the drive component 222, and the three are arranged at intervals along the material flow direction.

[0067] The final polycondensation reactor 300 refers to the subsequent reaction equipment used to continue the polycondensation reaction of the pre-polycondensation material from the second discharge port 2212. The final polycondensation reactor 300 is connected to the second discharge port 2212 and is used to further increase the degree of polymerization of the material and form the target polyester product.

[0068] Understandably, when the continuous production unit starts up, the material that has completed preliminary esterification in the esterification reactor 100 continuously enters the second reactor body 221 through the second feed inlet 2211. The drive unit 222 drives the first stirring component 223, the second stirring component 224, and the third stirring component 225, which are arranged sequentially and at intervals along the direction from the second feed inlet 2211 to the second discharge outlet 2212, to continuously process and transport the material. Subsequently, the material enters the final polycondensation reactor 300 through the second discharge outlet 2212 to continue the polycondensation reaction. Since the first stirring component 223, the second stirring component 224, and the third stirring component 225 are arranged sequentially and at intervals along the material flow direction, the material can pass through the action of different blade areas in the continuous flow process, thereby continuously stirring the pre-polymerized material, ensuring that the reactants are fully mixed and reacted, improving reaction efficiency, reducing raw material loss, and the formed prepolymer enters the final polycondensation reactor 300, realizing the continuous connection between the esterification reaction, the pre-polycondensation reaction, and the final polycondensation reaction.

[0069] It should be understood that the above examples are merely illustrative and not limiting, and can be adjusted accordingly without departing from the concept of this application.

[0070] In one possible implementation, reference is made to Figure 2 As shown, the first stirring component 223 is a cage-type disc with multiple through holes 2231.

[0071] The second stirring assembly 224 includes multiple disc groups, which are spaced apart along the extension direction of the drive member 222. Each disc group includes a connector 2241 and at least two discs 2242, which are disposed on the drive member 222. At least two discs 2242 are connected by the connector 2241.

[0072] Combination Figure 2 and Figure 4 As shown, the third stirring component 225 consists of multiple discs, which are spaced apart along the extension direction of the drive component 222, and each disc has a groove 2251.

[0073] Understandably, the cage-like disc in the first stirring assembly 223 is a disc-shaped mass transfer component installed on the drive component 222. It is mainly used to agitate and disperse the material and enhance gas-liquid contact in the pre-condensation stage to promote material homogenization and volatilization of small molecules.

[0074] The cage-like disc can be fixedly connected to the outer periphery of the drive component 222, or it can be installed on the drive component 222 via a detachable connector 2241 and arranged in the second prepolymerization reactor 220 on the side near the second feed inlet 2211, so that the oligomers entering from the esterification reactor 100 are first subjected to the action of the cage-like disc.

[0075] like Figure 2 As shown, multiple through holes 2231 penetrate the cage disc to form a fluid channel. When the drive unit 222 drives the cage disc to rotate, the material can pass through the through holes 2231 and form local shear at the edge of the hole, thereby improving the distribution of the material in the reactor.

[0076] In one possible implementation, the cage tray can be a circular cage tray, an elliptical cage tray, or a frame-type cage tray with reinforcing ribs. The through hole 2231 can be set as a round hole, an oblong hole, or an irregular hole. The material can be stainless steel, corrosion-resistant alloy, or high-strength metal with a polished surface, to adapt to the use environment of the polyester system under high temperature and reduced pressure conditions. No specific restrictions are imposed.

[0077] The outer diameter of the cage-type disc is usually fitted with a clearance fit to the inner diameter of the second reactor body 221 to avoid interference with the cylinder wall.

[0078] Of course, based on the above structure, the cage plate can also be replaced with a grid plate, frame plate or perforated plate according to process requirements, and the through hole 2231 can also be set as a variable aperture structure. It should be understood that the above examples are only for demonstration and are not limited.

[0079] Reference Figure 2 As shown, the second stirring assembly 224 includes multiple disc groups, which are spaced apart along the extension direction of the drive member 222. Each disc group includes a connector 2241 and at least two discs 2242. The discs 2242 are disposed on the drive member 222, and at least two discs 2242 are connected by the connector 2241. This structure forms a grouped stirring component for performing multi-stage shearing, film turning and renewal on the material in the middle pre-condensation zone, thereby enhancing the devolatilization efficiency and improving the uniformity of material heating.

[0080] The disk 2242 can be a round disk, a sector disk, or an irregularly shaped disk with an opening. The connector 2241 can be a rod, a bridging plate, or an annular connecting ring. The disk 2242 and the connector 2241 can be assembled by welding, screwing, or snapping. Adjacent disks 2242 in the disk assembly can form a fixed angle or be arranged in parallel, without any specific restrictions.

[0081] It is understood that the third stirring component 225 can be multiple discs, which are spaced apart along the extension direction of the drive component 222. The discs have grooves 2251. The third stirring component 225 is used to perform film pulling, confluence and reversal guidance on high viscosity materials in the later pre-condensation stage to enhance material surface renewal and promote the removal of residual volatile components.

[0082] Combination Figure 2 and Figure 4 As shown, multiple discs are arranged on the side of the drive unit 222 near the second discharge port 2212 and spaced apart along the axial direction, so that after the material enters the high viscosity area, it passes through the repeated action of multiple discs in sequence, gradually forming a thinner flow layer and a more sufficient contact interface.

[0083] The groove 2251 is provided on the surface of the disk to locally retain and guide the material during rotation, so that the material forms a thin film flow along the path of the groove 2251 and is deflected and redistributed between adjacent disks.

[0084] The disk can be a solid disk or a disk with an arc edge, and the groove 2251 can be a corrugated groove, a toothed groove or a composite groove. It should be understood that the above examples are for demonstration purposes only and are not limiting.

[0085] Specifically, a cage-type disc, multiple disc groups, and a disc with grooves 2251 are sequentially arranged in the opposite direction of the material flow. After the material enters the second prepolymerization reactor 220, it is first dispersed and initially agitated at the cage-type disc through multiple through holes 2231, achieving homogenization and initial removal of volatile components by means of the shearing effect at the hole edge.

[0086] Subsequently, when the material enters the middle section area composed of multiple disc groups, the spacing between the disc groups and the combined structure formed by the disc 2242 and the connector 2241 can continuously divide, stretch and fold the material, so that the surface of the fresh material is continuously renewed and the devolatilization process is enhanced.

[0087] As the material viscosity increases further and moves toward the second discharge port 2212, the grooves 2251 on the multiple discs guide and thin the material, enabling it to maintain effective flow and a large mass transfer interface even under high viscosity conditions.

[0088] With this setup, through a progressive action consisting of front-end dispersion, mid-stage enhanced shearing, and rear-stage film drawing and guiding, the material can achieve a more uniform temperature distribution and reaction process in the pre-polymerization stage. Unreacted monomers and small molecule volatiles can be removed more stably, resulting in a more consistent state of the material entering the final polymerization reactor 300. This, in turn, helps to improve the stability and batch consistency of polyester molecular weight, and enhances the adaptability and production efficiency of the unit during continuous operation.

[0089] It should be understood that the above examples are for illustrative purposes only and are not intended to be limiting.

[0090] In one possible implementation, such as Figure 2 As shown, it also includes a scraper 226. One end of the scraper 226 is fixed to the second reactor body 221, and the other end of the scraper 226 extends toward the drive member 222. This end of the scraper 226 is located between two adjacent third stirring components 225. The scraper 226 located between two adjacent third stirring components 225 has a pointed tip.

[0091] Among them, such as Figure 2 As shown, one end of the scraper 226 can be fixed to the second reactor body 221, and the other end can extend into the space between two adjacent third stirring components 225. When the third stirring component 225 rotates with the drive component 222, the third stirring component 225 carries fluid and solid particles to continuously impact the pointed scraper 226; the pointed structure can form a high shear flow field, cut and break up agglomerated materials, reduce mass transfer distance, and improve material mixing and reaction efficiency.

[0092] Specifically, as the viscosity of the material increases, the resistance to pushing the material increases in the area where the third stirring component 225 is located. At this time, the scraper 226 fixed in the second reactor body 221 constrains the flow field between the adjacent third stirring components 225. The material is diverted to both sides of the scraper 226 under the guidance of the tip and continuously updates the interface in the circulating flow formed by the rotation of the third stirring component 225, thereby reducing local retention and back mixing.

[0093] Furthermore, the scraper 226 has a pointed end, which can cut and break up agglomerated materials as they pass through, making them less prone to accumulation. This reduces the probability of dead zone formation and improves mass transfer conditions, allowing the esterified material to complete further polycondensation and volatile component removal more uniformly in the pre-polymerization stage, thereby improving the consistency of the material state before entering the final polycondensation reactor 300.

[0094] This configuration helps to enhance the flow field stability and material throughput inside the second prepolymerization reactor 220, and provides more uniform feeding conditions for the subsequent final polymerization process, thereby improving the operational stability of the continuous production unit, the consistency of polyester products, and the overall continuous production effect.

[0095] It should be understood that the above examples are for illustrative purposes only and are not intended to be limiting.

[0096] Furthermore, in combination Figure 2 and Figure 3 As shown, the tip of the scraper 226 is located on one side of the drive member 222, and the other end of the scraper 226 is located on the other side of the drive member 222 and connected to the second reactor body 221. The scraper 226 partially covers the drive member 222, and there is a gap 227 between the scraper 226 and the covered part of the drive member 222.

[0097] Combination Figure 2 and Figure 3 As shown, the scraper 226 extends radially across both sides of the drive member 222 along the second reactor body 221. The scraper 226 can be divided into a fixed section, a middle covering section, and a pointed section.

[0098] Specifically, the fixed section is located on one side of the drive component 222 and is fixedly connected to the inner wall of the second reactor body 221, so as to realize the overall static limitation of the scraper 226. During the operation, the scraper 226 remains stationary and does not rotate synchronously with the drive component 222 and the third stirring component 225.

[0099] like Figure 3 As shown, during the extension of the scraper 226 from the second reactor body 221 to the drive member 222, the middle covering section is laid on the outside of the drive member 222, forming a partial covering relationship; the covered area of ​​the scraper 226 does not fit with the outer wall of the drive member 222, and the gap 227 between the two forms an annular or strip-shaped gap 227; the gap 227 is circumferential or axial along the outer periphery of the drive member 222, leaving a fluid flow area.

[0100] The scraper 226 passes through the outside of the drive member 222, crosses the gap 227, and extends to the side of the drive member 222 facing the third stirring assembly 225. This end can be processed into a pointed tip, which is inserted between two adjacent third stirring assemblies 225.

[0101] With this configuration, the scraper 226 can cut and break up agglomerated materials near the third stirring component 225 without participating in rotation, reducing mass transfer distance and improving material mixing and reaction efficiency. Furthermore, the gap 227 maintained between the scraper 226 and the covered part of the drive component 222 allows the drive component 222 to rotate smoothly even under conditions of temperature rise, vibration, or manufacturing errors, avoiding wear, heat generation, or stalling caused by hard contact.

[0102] In addition, the material can maintain a relatively stable residence time distribution and a more uniform small molecule removal environment during the pre-condensation stage, which is conducive to improving the sufficiency of the pre-condensation reaction and providing intermediate materials with a more consistent state for the subsequent final condensation process. This improves the stability of the continuous production process, reduces local material accumulation and mechanical interference problems, and enhances the reliability of the long-term continuous operation of the equipment.

[0103] It should be understood that the above embodiments are only used to illustrate the technical concept of this application. The specific structural parameters and material selection can be adjusted according to the equipment specifications, material characteristics and working conditions, and are not intended to limit the scope of protection of this application.

[0104] In one possible implementation, such as Figure 2 As shown, the drive unit 222 includes a first main shaft 2221 and a second main shaft 2222. Both the first main shaft 2221 and the second main shaft 2222 are located on the axis of the second reactor body 221. The first main shaft 2221 is inserted into one end of the second reactor body 221, and the second main shaft 2222 is inserted into the other end of the second reactor body 221. The first stirring assembly 223 is disposed on the first main shaft 2221, and the second stirring assembly 224 and the third stirring assembly 225 are disposed on the second main shaft 2222.

[0105] The first main shaft 2221 and the second main shaft 2222 constitute a double-ended drive shaft system for supporting and driving the rotation of the blades inside the first prepolymerization reactor 210.

[0106] The first main shaft 2221 carries the first stirring assembly 223 near the second feed inlet 2211, and the second main shaft 2222 carries the second stirring assembly 224 and the third stirring assembly 225 near the second discharge outlet 2212. Both the first and second main shafts 2221 are arranged along the axis of the second reactor body 221, ensuring that their rotation centers align with the material flow direction inside the second reactor body 221. This facilitates the axial transport, agitation, and devolatilization of the reactants by the blades.

[0107] The first main shaft 2221 is inserted at one end of the second reactor body 221, and the second main shaft 2222 is inserted at the other end of the second reactor body 221. The two are supported by bearing seats, sealing structures or end cap assemblies respectively and connected to an external drive source to form a symmetrically arranged power input structure to adapt to the working condition of the material gradually changing from low viscosity to high viscosity in the pre-condensation stage.

[0108] It is understandable that the first stirring component 223 is set on the first main shaft 2221, and the second stirring component 224 and the third stirring component 225 are set on the second main shaft 2222. The rotation speed of the first main shaft 2221 and the second main shaft 2222 can be divided according to the reaction zone. The area of ​​the first stirring component 223 is more suitable for the initial stirring and homogenization of the oligomers entering the second reactor body 221, while the areas of the second stirring component 224 and the third stirring component 225 are more suitable for the forced agitation of the thickened material, the renewal of the heat transfer interface and the promotion of the removal of small molecule volatile components.

[0109] Specifically, by setting the first main shaft 2221 and the second main shaft 2222, the rotation speed can be controlled synchronously or slightly differently according to the rheological characteristics of the material. This allows the first stirring component 223, the second stirring component 224, and the third stirring component 225 to maintain a relatively stable posture and movement trajectory throughout the entire reaction area. This enhances the material tumbling frequency and contact uniformity, improves the stirring uniformity and heat and mass transfer efficiency under high viscosity material conditions, and helps reduce local stagnation and incomplete reaction, thereby improving the stability of the continuous production process and product consistency.

[0110] In addition, it should be noted that a viscosity sensor 700 can be installed inside the second reactor body 221. The viscosity sensor 700 can detect the viscosity of the material inside the second reactor body 221. The first main shaft 2221 and the second main shaft 2222 can adjust their rotation speed according to the viscosity data fed back by the viscosity sensor 700, so as to fully stir the material, fully mix the reaction, improve the utilization rate of raw materials, and avoid incomplete reaction.

[0111] It should be understood that the above examples are merely illustrative and not limiting. Without departing from the technical concept of this application, the support form, drive connection method, and installation structure with the blades of the first main shaft 2221 and the second main shaft 2222 can be adapted.

[0112] In one possible implementation, such as Figure 1 and Figure 5As shown, the first prepolymerization reactor 210 has a first inlet 211 and a first outlet 212. The first prepolymerization reactor 210 includes a first cylinder 213 and a second cylinder 214 disposed outside the first cylinder 213. The first cylinder 213 has a reaction chamber 215. An annular cavity 216 is formed between the second cylinder 214 and the first cylinder 213. An overflow port 2131 is provided on the first cylinder 213. The overflow port 2131 is used to connect the reaction chamber 215 and the annular cavity 216. The first inlet 211 is used to connect the reaction chamber 215 and the esterification reactor 100. The first outlet 212 is used to connect the annular cavity 216 and the second inlet 211.

[0113] The first prepolymerization reactor 210 is a reaction unit used for prepolymerization and intermediate conditioning of esterified materials.

[0114] like Figure 5 As shown, the first prepolymerization reactor 210 is formed by a first inner cylinder 213 and a second outer cylinder 214 coaxially or nearly coaxially fitted together. The first cylinder 213 defines the main reaction space, namely the reaction chamber 215. An annular cavity 216 for material transfer, devolatilization and buffering is formed between the second cylinder 214 and the first cylinder 213. An overflow port 2131 is located at the upper or upper middle part of the first cylinder 213 and connects the reaction chamber 215 and the annular cavity 216.

[0115] The first cylinder 213 can be understood as an inner cylinder structure that carries the main reaction process. Its function is to provide a relatively concentrated reaction space for the prepolymerization material and form a controllable flow path.

[0116] The second cylinder 214 is an outer cylinder structure that covers the outer periphery of the first cylinder 213. Its function is to form an annular cavity 216 together with the first cylinder 213 in order to realize material transfer, heat compensation or further volatilization.

[0117] The first cylinder 213 and the second cylinder 214 can be arranged coaxially, eccentrically, or partially covered to achieve a fit. The first cylinder 213 is fixed to the equipment support or adjacent pipelines by means of flanges, welding, or detachable connection. The second cylinder 214 forms an external enclosure structure around the first cylinder 213 and can be used in conjunction with insulation layers, jackets, or external heat exchange systems to enhance thermal management capabilities.

[0118] Overflow port 2131 is used to establish a communication channel between reaction chamber 215 and annular cavity 216. It can automatically realize overflow and displacement when the material liquid level reaches the position of overflow port 2131 or under the action of internal pressure difference, thereby avoiding the material from staying in a single cavity for a long time.

[0119] like Figure 5As shown, the overflow port 2131 can be located on the upper side wall of the first cylinder 213, in the adjacent area of ​​the top, or at multiple height positions arranged at intervals along the axial direction. The overflow port 2131 can be a round hole, an elongated hole, a slot, a connecting pipe, or an adjustable diameter structure with throttling characteristics, so as to control the material transfer speed and the residence time in the reaction chamber 215.

[0120] In one possible implementation, a guide plate, a straightening arc surface, or an anti-clogging mesh can be provided around the overflow port 2131 to reduce the accumulation of highly viscous materials at the opening.

[0121] Combination Figure 5 As shown, the first inlet 211 can be arranged on the lower side or end of the first cylinder 213 so that the material can be quickly distributed in the reaction chamber 215 under the action of gravity, pumping pressure or internal stirring of the cylinder after entering. The first outlet 212 is located on the downstream side of the annular cavity 216 or near the connection end of the first prepolymerization reactor 210, and is used to output the material after overflow transfer to the second inlet 2211, thereby forming a series passage between the second prepolymerization reactor 220 and the first prepolymerization reactor 210.

[0122] Specifically, the esterified material in the esterification reactor 100 first enters the reaction chamber 215 of the first prepolymerization reactor 210 through the first feed port 211. In the reaction chamber 215, it undergoes further heating and initial removal of small molecules. As the liquid level in the reaction chamber 215 rises or under the action of internal fluid pressure, it enters the annular cavity 216 through the overflow port 2131 to continue to stay and undergo secondary prepolymerization and devolatilization within the space defined by the second cylinder 214. Then, it is output from the first discharge port 212 to the second feed port 2211 and enters the second prepolymerization reactor 220.

[0123] It is understandable that by setting up a first cylinder 213 and a second cylinder 214 with inner and outer double layers, the material can obtain a more reasonable residence time distribution and heat transfer conditions in different cavities, thereby making the viscosity rise of the material more gradual, the volatile components more fully removed, and back mixing avoided.

[0124] It should be understood that the above examples are for demonstration purposes only and are not limiting. Without departing from the concept of this application, the cylindrical form of the first prepolymerization reactor 210, the structure of the overflow port 2131, the position of the inlet and outlet interfaces, and the size ratio can all be adjusted according to the equipment scale and process conditions.

[0125] Furthermore, the ratio of the diameter of the second cylinder 214 to the diameter of the first cylinder 213 is greater than or equal to 1.5 and less than or equal to 2.2.

[0126] The second cylinder 214 is a pressure-bearing cylinder outside the first prepolymerization reactor 210, used to cover the first cylinder 213 and together with the first cylinder 213 define the annular cavity 216. The ratio of the diameter of the second cylinder 214 to the diameter of the first cylinder 213 is usually controlled within the range of greater than or equal to 1.5 and less than or equal to 2.2, so that the cross-sectional dimensions of the annular cavity 216 take into account both the flow capacity and the uniformity of residence distribution.

[0127] In one possible implementation, the second cylinder 214 includes a straight cylinder section 2141 and a conical cylinder section 2142 connected to the straight cylinder section 2141. The diameter of the conical cylinder section 2142 gradually decreases in the direction away from the straight cylinder section 2141, and the ratio of the diameter of the straight cylinder section 2141 to the diameter of the conical cylinder section 2142 is greater than or equal to 1.2 and less than or equal to 2.

[0128] The second cylinder 214 also includes a straight section 2141 and a conical section 2142 connected to the straight section 2141. The straight section 2141 constitutes the main stable flow and buffer volume area, while the conical section 2142 is used to gradually contract and guide the material in the annular cavity 216, so that the material converges, pressurizes and redistributes the flow rate during the geometric transition process, thereby improving the continuity of discharge of high-viscosity materials.

[0129] Furthermore, the ratio of the diameter of the straight section 2141 to the diameter of the conical section 2142 can be greater than or equal to 1.2 and less than or equal to 2. This setting helps to ensure that the conical section 2142 has sufficient flow guiding effect while avoiding excessive contraction angle that could cause local stagnation or material backflow.

[0130] In one possible implementation, such as Figure 6 and Figure 7 As shown, the final polycondensation reactor 300 includes a horizontal cylindrical body 310, a drive shaft 320, multiple cleaning discs 330, and multiple cleaning blade assemblies 340. The drive shaft 320 is inserted into the horizontal cylindrical body 310 along its extension direction. The multiple cleaning discs 330 are disposed on the drive shaft 320 and are spaced apart along the extension direction of the drive shaft 320. The multiple cleaning blade assemblies 340 are disposed at the edges of the cleaning discs 330 and are used to adhere to the inner wall of the horizontal cylindrical body 310 to clean the horizontal cylindrical body 310 and the cleaning discs 330.

[0131] The drive shaft 320 is a transmission component that is located inside the horizontal cylinder 310 and can rotate around its own axis. The drive shaft 320 can be a solid shaft, a hollow shaft, or a shaft with internal cooling medium to improve transmission stability and thermal management capability.

[0132] The horizontal cylinder 310 can be configured as a cylindrical shell, a jacketed heating cylinder, or a sealed cylinder with a vacuum extraction port; there are no specific restrictions.

[0133] Multiple cleaning discs 330 are fixed on the drive shaft 320 and rotate synchronously with the drive shaft 320. Multiple cleaning blade sets 340 are installed at the edge of the cleaning discs 330 and extend toward the inner wall of the horizontal cylinder 310, thereby forming a continuous scraping of the inner wall of the cylinder during rotation, reducing dead corner retention and local wall hanging phenomenon.

[0134] The cleaning disc 330 can be a disc-shaped structure, a reinforcing disc-shaped structure, or a ring-shaped structure with openings; the cleaning blade assembly 340 can be a plate-shaped cleaning blade assembly 340, an arc-shaped cleaning blade assembly 340, or an elastic scraper.

[0135] In addition, the number of cleaning discs 330 and cleaning blades 340 can be configured according to the length of the cylinder, the viscosity of the material and the target residence time. In a longer cylinder, multiple cleaning discs 330 can be set to form a continuous cleaning band, while in a shorter cylinder, the cleaning effect can be ensured by reducing the disc spacing or increasing the coverage of the cleaning blades 340.

[0136] It should be understood that the above-mentioned shapes, materials, connection methods and size proportions are for illustrative purposes only and are not limitations.

[0137] In one possible implementation, reference is made to Figure 6 As shown, two drive shafts 320 are arranged in parallel. The cleaning disc 330 includes a disc body 331 and a hub 332. The hub 332 is located at the center of the disc body 331 and is sleeved on the drive shaft 320. The cleaning discs 330 on the two drive shafts 320 are arranged alternately. The two drive shafts 320 are configured to rotate synchronously in opposite directions or in the same direction.

[0138] like Figure 6 As shown, two drive shafts 320 can be arranged in parallel. Both drive shafts 320 extend axially along the horizontal cylinder 310, respectively carrying the corresponding cleaning discs 330 and coordinating the movement of materials. The two drive shafts 320 are spaced apart, so that adjacent cleaning discs 330 can effectively cover each other when rotating without mechanical interference.

[0139] This configuration enhances the kneading, tumbling, and renewal of contact of high-viscosity polyester materials during the final polycondensation stage, thereby improving heat and mass transfer conditions and enhancing the self-cleaning ability of the inner wall of the cylinder.

[0140] like Figure 7 As shown, the cleaning disc 330 is the main working component in the final polycondensation reactor 300. The disc body 331 is used to scrape, roll and disperse the material, while the hub 332 can realize the reliable connection and torque transmission between the disc body 331 and the drive shaft 320.

[0141] The disc body 331 can be made into a disc-shaped, willow-leaf-shaped, crescent-shaped, or perforated split-flow structure, and the hub 332 can adopt a metal sleeve-shaped, keyway sleeve-shaped, or fastening flange-shaped structure, without any specific restrictions.

[0142] Specifically, two parallel drive shafts 320 operate synchronously at a set speed under the drive of a power mechanism, and can rotate in opposite directions or in the same direction as required by the process. The cleaning discs 330 mounted on the two drive shafts 320 rotate accordingly. During the rotation of the adjacent discs 331, they alternately push, roll, and switch the flow direction of the high-viscosity polyester melt in the final polycondensation reactor 300. The material is continuously divided and renewed between the two shafts and conveyed to the middle of the cylinder and the discharge end, thereby reducing local stagnation and dead zone accumulation.

[0143] Meanwhile, the cleaning blade assembly 340 on the outer edge of the disc 331 can sweep the inner wall of the horizontal cylinder 310, which can promptly peel off the material adhering to or deposited on the wall and reintroduce it into the main flow area. This configuration enables conveying, mixing, and wall scraping cleaning, thereby improving heat and mass exchange conditions, reducing the probability of cylinder scaling and local overheating, and improving reaction uniformity and product batch consistency.

[0144] It should be understood that the above examples are for illustrative purposes only and are not intended to be limiting.

[0145] In one possible implementation, the cleaning disc 330 is a disc, a willow leaf disc, or a crescent-shaped shovel disc.

[0146] Understandably, a disc is suitable for forming a relatively uniform radial pushing flow field; a willow leaf disc can be a disc body 331 with an arc-shaped edge and an overall profile similar to a blade, which can enhance the tangential shearing and axial conveying of highly viscous materials when rotating; a crescent-shaped shovel disc can be a disc body 331 with a crescent-shaped arc edge and a shovel edge, and its local openings or arc-shaped cuts are conducive to forming a stronger material turning and shoveling effect.

[0147] Specifically, the selection of discs, willow leaf discs, and crescent-shaped shovel discs can be matched according to the material state, equipment scale, and expected residence time in the final polycondensation stage. In addition, the disc body 331 of the cleaning disc 330 can be further extended into other equivalent structures such as plum blossom discs, fan-shaped discs, or combined discs according to the actual process, without specific limitations.

[0148] In one possible implementation, such as Figure 2 and Figure 6As shown, it also includes multiple nozzles 400. Both the second prepolymerization reactor 220 and the final polymerization reactor 300 are equipped with nozzles 400. The nozzles 400 are spaced apart along the axial direction of the second prepolymerization reactor 220 and the final polymerization reactor 300. The nozzles 400 are used to spray diol vapor toward the inner wall of the second prepolymerization reactor 220 and the final polymerization reactor 300 for cleaning treatment.

[0149] Among them, multiple nozzles 400 are spraying components used to directionally spray cleaning media into the reactor. Their main function is to use diol vapor to clean the inner walls of the second prepolymerization reactor 220 and the final polymerization reactor 300 online. Together with the cleaning blade assembly 340, they further remove polymer deposits, oligomer deposits, and wall-mounted materials that may affect heat and mass transfer efficiency formed or remaining during the polyester polycondensation process, thereby maintaining the stability of heat exchange conditions and material flow state inside the reactor.

[0150] The nozzle 400 can be installed on the inner wall, end wall, or cleaning interface connected to the cylinder of the second prepolymerization reactor 220 and the final polymerization reactor 300, and arranged at intervals along the axial direction of the corresponding reactor, so that the diol vapor can cover different axial areas and avoid cleaning dead corners due to insufficient local spray range.

[0151] In one possible implementation, the nozzle 400 may be an atomizing nozzle 400, a fan-shaped nozzle 400, or a directional nozzle; the orifice diameter, spray angle, and nozzle spacing of the nozzle 400 are typically matched and set according to the reactor cylinder diameter, axial length, and target cleaning range.

[0152] It should be understood that the structure, material selection, and arrangement of the above-mentioned nozzle 400 can be adjusted according to the specific equipment structure and cleaning requirements. The nozzle 400 can also be replaced by a nozzle assembly, spray pipe, or rotatable spray arm. The cleaning medium can also be other suitable steam or cleaning gas if the process conditions are met. The above examples are for demonstration purposes only and are not limited.

[0153] Understandably, the nozzle 400 can be used to deliver diol vapor into the second prepolymerization reactor 220 and the final polymerization reactor 300. Under high temperature conditions, the vapor softens and dissolves the polymer residues adhering to the cylinder wall, end wall, and local dead corners. The vapor also peels off the loose adhering layer with the help of jet momentum, reducing the probability of residues adhering to the wall surface. This restores the inner surface of the reactor to a better smooth state, and the heat transfer resistance and local flow resistance are reduced accordingly. This improves the heating uniformity, devolatilization efficiency, and polymerization stability of the subsequent polyester materials in the prepolymerization and final polymerization stages. It is beneficial to maintain stable operation in the continuous production process and reduce product fluctuations and downtime cleaning frequency caused by fouling.

[0154] In one possible implementation, such as Figure 1 As shown, the esterification reactor 100 includes a first esterification reactor 110 and a second esterification reactor 120 connected in sequence, with the second esterification reactor 120 connected to the first feed inlet 211.

[0155] The second esterification reactor 120 includes a reactor body 121 and a plurality of agitators 122. The reactor body 121 has a plurality of chambers arranged sequentially along the extension direction of the reactor body 121, and agitator 122 is provided in each chamber.

[0156] The first esterification reactor 110 and the second esterification reactor 120 constitute a series reaction unit in the esterification stage. The first esterification reactor 110 is used for preliminary heating, mixing and esterification of polyester raw materials, while the second esterification reactor 120 is used to receive the products from the previous reaction and continue to complete the subsequent esterification process, so that the material has reached a suitable degree of reaction before entering the first feed inlet 211 of the prepolymerization reactor 200.

[0157] The second esterification reactor 120 can be a multi-chamber reactor for staged esterification reactions. Its interior is axially divided into multiple chambers, allowing the material to remain and react segmentally along the extension direction of the reactor body 121. Multiple agitators 122 are respectively disposed in corresponding chambers to stir, agitate, and homogenize the material within their respective chambers, thereby enhancing heat and mass transfer and reducing local concentration and temperature gradients.

[0158] like Figure 1 As shown, the first esterification reactor 110 can be connected to the second esterification reactor 120 through pipelines, valve groups or overflow channels, and the discharge end of the second esterification reactor 120 is connected to the first feed port 211 so that the material after the first esterification is continuously fed into the subsequent prepolymerization system.

[0159] In one possible implementation, the first esterification reactor 110 and the second esterification reactor 120 can respectively adopt a jacketed cylindrical body or a horizontal vessel structure. The chambers of the reactor body 121 can be formed by built-in baffles or by modular segmented cylindrical bodies spliced ​​together. The number of chambers can be set according to the production capacity requirements and reaction residence time, and is usually two, three or more chambers.

[0160] Understandably, by arranging multiple chambers along the material flow direction within the reactor body 121, the stirring element 122 in each chamber further mixes and renews the interface of the material, thereby advancing the reaction step by step and improving the removal efficiency of small molecules. Furthermore, the chambers are spatially separated, allowing the material to obtain a residence environment adapted to its viscosity and degree of reaction at different stages, avoiding problems such as local stagnation, uneven heat transfer, and incomplete reaction that are prone to occur in reactors.

[0161] It should be understood that the above examples are for illustrative purposes only and are not intended to be limiting.

[0162] In one possible implementation, the continuous production apparatus for the polyester further includes a slurry preparation structure 500, which is connected to the inlet of the esterification reactor 100.

[0163] Understandably, the liquid and solid raw materials for polyester preparation can be first transported to the slurry mixing structure 500 to precisely control the solid-liquid ratio and slurry concentration. This allows for early homogenization and mixing before the materials enter the esterification reactor 100, thus avoiding an imbalance in the raw material ratio.

[0164] In one possible implementation, the continuous polyester production apparatus further includes a pelletizing unit 600, which is connected to the outlet of the final polymer reactor. The material produced by the final polymer reactor can be conveyed to the pelletizing unit 600, where pelleting is completed to ensure the quality and appearance of the output.

[0165] Finally, it should be noted that other embodiments of this application will readily conceive of by those skilled in the art upon consideration of the specification and practice of the application disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from its scope.

Claims

1. A continuous production apparatus for polyester, characterized in that, include: Esterification reactor (100); A prepolymerization reactor (200) includes a first prepolymerization reactor (210) and a second prepolymerization reactor (220). The second prepolymerization reactor (220) includes a second reactor body (221), a drive unit (222), a first stirring assembly (223), a second stirring assembly (224), and a third stirring assembly (225). The second reactor body (221) has a second inlet (2211) and a second outlet (2212). (2211) is connected to the first prepolymerization reactor (210), the first prepolymerization reactor (210) is connected to the esterification reactor (100), the drive (222) is inserted into the second reactor body (221), the first stirring assembly (223), the second stirring assembly (224) and the third stirring assembly (225) are all disposed on the drive (222), and are arranged at intervals along the direction from the second feed inlet (2211) to the second discharge outlet (2212); A final polycondensation reactor (300) is connected to the second discharge port (2212).

2. The continuous polyester production apparatus according to claim 1, characterized in that, The first stirring assembly (223) is a cage-type disc, and the cage-type disc has multiple through holes (2231). The second stirring assembly (224) includes a plurality of disc groups, which are spaced apart along the extending direction of the drive member (222). Each disc group includes a connector (2241) and at least two discs (2242). The discs (2242) are disposed on the drive member (222), and at least two discs (2242) are connected by the connector (2241). The third stirring assembly (225) consists of multiple discs, which are spaced apart along the extension direction of the drive member (222), and each disc has a groove (2251).

3. The continuous polyester production apparatus according to claim 2, characterized in that, It also includes a scraper (226), one end of which is fixed to the second reactor body (221), and the other end of which extends toward the drive member (222). The scraper (226) is located between two adjacent third stirring components (225), and the scraper (226) located between two adjacent third stirring components (225) is pointed.

4. The continuous polyester production apparatus according to claim 3, characterized in that, The tip of the scraper (226) is located on one side of the drive member (222), and the other end of the scraper (226) is located on the other side of the drive member (222) and connected to the second reactor body (221). The scraper (226) partially covers the drive member (222), and there is a gap (227) between the scraper (226) and the covered part of the drive member (222).

5. The continuous polyester production apparatus according to claim 1, characterized in that, The drive unit (222) includes a first main shaft (2221) and a second main shaft (2222). The first main shaft (2221) and the second main shaft (2222) are both located on the axis of the second reactor body (221). The first main shaft (2221) is inserted into one end of the second reactor body (221), and the second main shaft (2222) is inserted into the other end of the second reactor body (221). The first stirring assembly (223) is disposed on the first main shaft (2221), and the second stirring assembly (224) and the third stirring assembly (225) are disposed on the second main shaft (2222).

6. The continuous polyester production apparatus according to claim 1, characterized in that, The first prepolymerization reactor (210) has a first inlet (211) and a first outlet (212). The first prepolymerization reactor (210) includes a first cylinder (213) and a second cylinder (214) disposed outside the first cylinder (213). The first cylinder (213) has a reaction chamber (215). An annular cavity (216) is formed between the second cylinder (214) and the first cylinder (213). An overflow port (2131) is provided on the first cylinder (213). The overflow port (2131) is used to connect the reaction chamber (215) and the annular cavity (216). The first inlet (211) is used to connect the reaction chamber (215) and the esterification reactor (100). The first outlet (212) is used to connect the annular cavity (216) and the second inlet (2211).

7. The continuous polyester production apparatus according to claim 6, characterized in that, The ratio of the diameter of the second cylinder (214) to the diameter of the first cylinder (213) is greater than or equal to 1.5 and less than or equal to 2.2; The second cylindrical body (214) includes a straight cylindrical section (2141) and a conical cylindrical section (2142) connected to the straight cylindrical section (2141). The diameter of the conical cylindrical section (2142) gradually decreases in the direction away from the straight cylindrical section (2141). The ratio of the diameter of the straight cylindrical section (2141) to the diameter of the conical cylindrical section (2142) is greater than or equal to 1.2 and less than or equal to 2.

8. The continuous production apparatus for polyester according to any one of claims 1-7, characterized in that, The final polycondensation reactor (300) includes a horizontal cylindrical body (310), a drive shaft (320), a plurality of cleaning discs (330), and a plurality of cleaning blade assemblies (340). The drive shaft (320) is inserted into the horizontal cylindrical body (310) along the extension direction of the horizontal cylindrical body (310). The plurality of cleaning discs (330) are disposed on the drive shaft (320) and are spaced apart along the extension direction of the drive shaft (320). The plurality of cleaning blade assemblies (340) are disposed at the edges of the cleaning discs (330) and are used to conform to the inner wall of the horizontal cylindrical body (310) to clean the horizontal cylindrical body (310) and the cleaning discs (330).

9. The continuous polyester production apparatus according to claim 8, characterized in that, Two drive shafts (320) are arranged in parallel. Each cleaning disc (330) includes a disc body (331) and a hub (332). The hub (332) is located at the center of the disc body (331) and is sleeved on the drive shaft (320). The cleaning discs (330) on the two drive shafts (320) are arranged alternately. The two drive shafts (320) are configured to rotate synchronously in opposite directions or in the same direction.

10. The continuous polyester production apparatus according to claim 9, characterized in that, The cleaning disc (330) is a round disc, a willow leaf disc, or a crescent-shaped shovel disc.

11. The continuous production apparatus for polyester according to any one of claims 1-7, characterized in that, It also includes multiple nozzles (400), which are provided in both the second prepolymerization reactor (220) and the final polymerization reactor (300). The nozzles (400) are spaced apart along the axial direction of the second prepolymerization reactor (220) and the final polymerization reactor (300). The nozzles (400) are used to spray diol vapor toward the inner wall of the second prepolymerization reactor (220) and the final polymerization reactor (300) for cleaning.

12. The continuous polyester production apparatus according to claim 6, characterized in that, The esterification reactor (100) includes a first esterification reactor (110) and a second esterification reactor (120) connected in sequence, and the second esterification reactor (120) is connected to the first feed inlet (211); The second esterification reactor (120) includes a reactor body (121) and a plurality of agitators (122). The reactor body (121) has a plurality of chambers, which are arranged sequentially along the extension direction of the reactor body (121), and each chamber is provided with a corresponding agitator (122).

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