Condensing reflux device and polyester synthesis production equipment

Abstract

The application discloses a condensing reflux device and a polyester synthesis production device, and relates to the technical field of polyester synthesis. The condensing reflux device comprises a cylinder, a jacket and a porcelain ring array. The cylinder has an inner cavity for accommodating a polyester synthesis process medium. The jacket is arranged on the outer periphery of the cylinder. The jacket and the cylinder form an outer cavity which is separated from the inner cavity. The outer cavity is used for passing in a refrigerating medium or a heating medium. The porcelain ring array is arranged in the inner cavity and is distributed along the axial direction of the cylinder. The porcelain ring array is configured to condense and accumulate the polyester synthesis process medium when the outer cavity passes in the refrigerating medium, and to heat and reflux the polyester synthesis process medium when the outer cavity passes in the heating medium. The condensing reflux device can realize online anti-blocking, ensure the accuracy of material proportioning and not introduce secondary pollution in the whole polyester synthesis process.

Description

Technical Field

[0001] This application relates to the field of polyester synthesis technology, and in particular to a condensation reflux device and polyester synthesis production equipment. Background Technology

[0002] Currently, during polyester synthesis, some acids or anhydrides (such as maleic anhydride and phthalic anhydride) and oligomers have high vapor pressures under high-temperature conditions, making them prone to sublimation and migration with the process gas flow. These substances crystallize upon cooling in the fractionation tanks or condensers of the polyester synthesis equipment, gradually depositing and growing. Due to stage-specific differences in reaction temperature, pressure, catalyst, and material properties, the volatilization rate fluctuates significantly, leading to the adhesion of large amounts of crystals or resinous oligomers to the tank walls. As the operating cycle lengthens, the deposit layer thickens, eventually completely blocking the channels. This blockage not only poses significant obstacles to subsequent synthesis, such as preventing the polymerization reaction from reaching its endpoint, causing polymer imbalances and structural distortions due to raw material loss, but also risks equipment corrosion due to long-term blockage by large amounts of acidic substances, resulting in equipment damage, production safety accidents, and increased maintenance costs. Existing technologies generally employ methods such as manual unblocking, mechanical scraping, or solvent rinsing. However, during implementation, it has been found that current methods cannot be used for continuous online processing, requiring shutdown for maintenance. Furthermore, manual or mechanical intervention increases labor intensity and safety hazards. In addition, cleaning wastewater can easily pollute water bodies, and leaked solvents may contaminate products, affecting product quality stability.

[0003] Therefore, the challenge lies in how to achieve online anti-clogging throughout the polyester synthesis process, ensure the accuracy of material proportions, and avoid introducing secondary pollution through a condensation reflux device. Utility Model Content

[0004] The purpose of this application is to provide a condensation reflux device and polyester synthesis production equipment that can achieve online anti-clogging and ensure the accuracy of material ratio throughout the polyester synthesis process, without introducing secondary pollution.

[0005] To achieve the above objectives, this application provides a condensation reflux device, comprising:

[0006] The cylindrical body has an inner cavity for containing the medium used in the polyester synthesis process;

[0007] A jacket is located on the outer periphery of the cylinder, forming an outer cavity that is separated from the inner cavity. The outer cavity is used to introduce a cooling medium or a heating medium.

[0008] The ceramic ring array, located in the inner cavity and distributed along the axial direction of the cylinder, is configured to: cause the polyester synthesis process medium to condense and accumulate when a cooling medium is introduced into the outer cavity, and cause the polyester synthesis process medium to be heated and refluxed when a heating medium is introduced into the outer cavity.

[0009] In some embodiments, the ceramic ring array includes several layers of ceramic ring units distributed along the axial direction of the cylinder, and any one of the ceramic ring units has a honeycomb structure.

[0010] In some embodiments, any two adjacent ceramic ring units are arranged in an alternating pattern.

[0011] In some embodiments, any ceramic ring unit includes a plurality of ceramic ring bodies, the inner surface of the ceramic ring body is provided with a rough layer, and the outer surface of the ceramic ring body is provided with a smooth layer.

[0012] In some embodiments, the aspect ratio of the ceramic ring body ranges from 1:2 to 1:3.

[0013] In some embodiments, one end of the cylinder is connected to an inlet flange and the other end is connected to an outlet flange. Both the inlet flange and the outlet flange include a flange body and a central orifice plate located at the center of the flange body.

[0014] In some embodiments, the condensation reflux device further includes an orifice plate septum disposed in the cylinder and in contact with the ceramic ring array for positioning the ceramic ring array.

[0015] In some embodiments, the orifice plate septum is spaced apart from the center orifice plate of the inlet flange, and a condensation reflux space is formed between the orifice plate septum and the center orifice plate of the inlet flange for condensation reflux of the polyester synthesis process medium.

[0016] In some embodiments, a first connector is provided at one end of the jacket near the inlet flange, and a second connector is provided at one end of the jacket near the outlet flange. Both the first and second connectors are connected to the outer cavity. The first connector is used to introduce the refrigerant and discharge the heating medium, and the second connector is used to introduce the heating medium and discharge the refrigerant.

[0017] This application also provides a polyester synthesis production apparatus, including the condenser reflux device described in any of the above claims.

[0018] Compared to the aforementioned background technology, the condensation reflux device provided in this application includes a cylinder, a jacket, and a ceramic ring array. The cylinder has an inner cavity for containing the polyester synthesis process medium. The jacket is located on the outer periphery of the cylinder, forming an outer cavity separated from the inner cavity. The outer cavity is used to introduce a cooling medium or a heating medium. The ceramic ring array is located in the inner cavity and distributed along the axial direction of the cylinder. The ceramic ring array is configured to: cause the polyester synthesis process medium to condense and accumulate when a cooling medium is introduced into the outer cavity; and cause the polyester synthesis process medium to be heated and refluxed when a heating medium is introduced into the outer cavity.

[0019] The beneficial effects of this condensation reflux device mainly include:

[0020] Firstly, by introducing a refrigerant into the outer cavity, which is located around the outer periphery of the cylinder, the cooling capacity of the refrigerant rapidly and uniformly cools the vapor of the polyester synthesis process medium through the ceramic ring array. This causes the polyester synthesis process medium, such as phthalic anhydride or oligomers, to condense on the ceramic ring array, and then crystallize and accumulate. This method of uniformly cooling the polyester synthesis process medium along the cylinder axis avoids the blockage caused by excessive local crystallization and accumulation in traditional cylinders.

[0021] Secondly, by introducing a heating medium into the external cavity, the heat from the heating medium is rapidly and evenly transferred to the crystallizing polyester synthesis process medium through the ceramic ring array. This maximizes the heating of any escaped polyester synthesis process medium, such as phthalic anhydride or oligomers, causing them to evaporate and flow back, thus achieving continuous online cleaning and ensuring the accuracy of material proportioning. Simultaneously, the cleaning process requires no shutdown for maintenance, significantly reducing manual labor intensity and safety hazards.

[0022] Third, the aforementioned cooling or heating medium is introduced into the outer cavity, which is separated from the inner cavity. In other words, the outer cavity and the inner cavity are independent cavities. The cooling or heating medium will not affect the polyester synthesis process medium in the inner cavity. This allows for online cleaning without introducing secondary pollution, ensuring the quality stability of the subsequently generated products. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the overall structure of the condensation reflux device in the embodiments of this application.

[0025] Figure 2 for Figure 1 Side view of the condenser reflux device shown.

[0026] Figure 3 for Figure 2 Sectional view of AA.

[0027] Figure 4 for Figure 1 Top view of the condenser reflux device shown.

[0028] Figure 5 for Figure 1 The diagram shows the structure of the ceramic ring array in the condenser reflux device.

[0029] Figure 6 for Figure 5 The diagram shows the structure of a single-layer ceramic ring unit in the ceramic ring array.

[0030] Figure 7 for Figure 5 The top view of the ceramic ring array shown.

[0031] Figure 8 This is a schematic diagram of the connection of the polyester synthesis production equipment in the embodiments of this application.

[0032] in:

[0033] 10-Cylinder body, 11-Inner cavity;

[0034] 20 - Jacket, 21 - External cavity;

[0035] 30 - Ceramic ring array, 31 - Ceramic ring unit, 311 - Ceramic ring body;

[0036] 40 - Inlet flange, 41 - Flange body, 42 - Center orifice plate;

[0037] 50 - Outlet flange;

[0038] 60-hole plate septum;

[0039] 70 - First connector;

[0040] 80 - Second connector;

[0041] 100-Reaction vessel;

[0042] 200-Shrinkage Unit;

[0043] 300-Condenser;

[0044] 400-Water collector. Detailed Implementation

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

[0046] To enable those skilled in the art to better understand the present application, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0047] It should be noted that the directional terms such as "upper end," "lower end," "left side," and "right side" mentioned below are defined based on the accompanying drawings in the instruction manual.

[0048] Please refer to Figures 1 to 8 , Figure 1 This is a schematic diagram of the overall structure of the condensation reflux device in the embodiments of this application. Figure 2 for Figure 1 Side view of the condenser reflux device shown. Figure 3 for Figure 2 Sectional view of AA. Figure 4 for Figure 1 Top view of the condenser reflux device shown. Figure 5 for Figure 1 The diagram shows the structure of the ceramic ring array in the condenser reflux device. Figure 6 for Figure 5 The diagram shows the structure of a single-layer ceramic ring unit in the ceramic ring array. Figure 7 for Figure 5 The top view of the ceramic ring array shown. Figure 8 This is a schematic diagram of the connection of the polyester synthesis production equipment in the embodiments of this application.

[0049] The condensation reflux device provided in this application includes a cylinder 10, a jacket 20, and a ceramic ring array 30. This condensation reflux device can be a distributor 200 or a condenser 300.

[0050] The cylinder 10 has an inner cavity 11 for containing the polyester synthesis process medium. Flanges are welded to both ends of the cylinder 10 and are tightly connected to the pipeline. The cylinder 10 includes, but is not limited to, straight cylinder or spiral cylinder structures.

[0051] The jacket 20 is located on the outer periphery of the cylinder 10. The jacket 20 can withstand a vapor pressure of more than 0.5 MPa. The jacket 20 and the cylinder 10 form an outer cavity 21 that is separated from the inner cavity 11. The outer cavity 21 is used to introduce a cooling medium or a heating medium.

[0052] The ceramic ring array 30 is disposed in the inner cavity 11 and distributed along the axial direction of the cylinder 10. The ceramic ring array 30 is configured to: cause the polyester synthesis process medium to condense and accumulate when the cooling medium is introduced into the outer cavity 21, and cause the polyester synthesis process medium to be heated and refluxed when the heating medium is introduced into the outer cavity 21.

[0053] By introducing a refrigerant into the outer cavity 21, which is located around the outer periphery of the cylinder 10, the cooling capacity of the refrigerant rapidly and uniformly cools the vapor of the polyester synthesis process medium through the ceramic ring array 30. This causes the polyester synthesis process medium, such as phthalic anhydride or oligomers, to condense on the ceramic ring array 30, and then crystallize and accumulate. This method of uniformly cooling the polyester synthesis process medium along the axial direction of the cylinder 10 avoids the blockage caused by excessive local crystallization and accumulation in traditional cylinders 10.

[0054] By introducing a heating medium into the external cavity 21, the heat from the heating medium is rapidly and uniformly transferred to the crystallizing polyester synthesis process medium through the ceramic ring array 30. This maximizes the heating of the polyester synthesis process medium that has escaped, such as phthalic anhydride or oligomers, causing them to evaporate and flow back. This achieves continuous online cleaning and ensures accurate material proportioning. Simultaneously, the cleaning process requires no shutdown for maintenance, significantly reducing manual labor intensity and safety hazards.

[0055] The aforementioned cooling or heating medium is introduced into the outer cavity 21, which is separated from the inner cavity 11. In other words, the outer cavity 21 and the inner cavity 11 are independent cavities. The cooling or heating medium will not affect the polyester synthesis process medium in the inner cavity 11. In this way, the purpose of online cleaning can be achieved without introducing secondary pollution, ensuring the quality stability of the subsequently generated products.

[0056] It should be noted that the media in the polyester synthesis process include phthalic anhydride and polyester oligomers. Based on literature review and practical experience, the melting point of phthalic anhydride and polyester oligomers is approximately 135℃, while the saturation temperature of water vapor at 0.5 MPa is approximately 151.83℃. Therefore, the jacket 20 is designed to be made of 316L stainless steel to withstand water vapor pressures greater than 0.8 MPa. Furthermore, water vapor is more environmentally friendly, economical, and applicable than the commonly used solvent ethylene glycol.

[0057] In some embodiments, the ceramic ring array 30 includes several layers of ceramic ring units 31 distributed along the axial direction of the cylinder 10, and any one of the ceramic ring units 31 has a honeycomb structure.

[0058] In this embodiment, any two adjacent ceramic ring units 31 are arranged in an alternating manner, and any ceramic ring unit 31 includes a plurality of ceramic ring bodies 311.

[0059] The ceramic ring array 30 is arranged as neatly and closely as possible within the cylinder 10, with adjacent ceramic ring bodies 311 in contact with each other (e.g., Figure 6 (Single-layer state shown). For example, two adjacent ceramic ring units 31 are staggered by 30° and arranged in multiple overlapping layers.

[0060] This design allows for the placement of up to approximately 450 ceramic ring bodies 311 within the cylinder 10, and maximizes the surface area through which steam flows, approximately 742203 mm². 2 This significantly increases the total contact area between the steam and the ceramic ring array 30, allowing more phthalic anhydride to be captured and crystallized on the ceramic ring array 30. During heating, the excellent thermal conductivity of the ceramic material enables the phthalic anhydride to melt and reflux quickly and uniformly, effectively solving the problem of phthalic anhydride sublimation clogging the pipes and ensuring the smooth progress of the polyester synthesis process.

[0061] It is important to emphasize that by setting up axial multilayer honeycomb ceramic ring units 31 to form a continuous and tortuous flow channel network, the gas phase is cut and turned multiple times in both the radial and axial directions, which significantly increases the degree of turbulence and prolongs the residence time. This increases the contact frequency between the steam and the cold wall surface of the ceramic ring unit 31, improves the condensation / capture efficiency, and at the same time, sublimable acid anhydrides and oligomers are more easily adsorbed and solidified by the cold surface of the ceramic ring unit 31, reducing the escape with the airflow.

[0062] In some embodiments, the ceramic ring body 311 is made of ceramic material, which can prevent the packing from leaking into the reactor 100 due to corrosion of the structural components by acid anhydrides, solvents and oligomers; the outer surface of the ceramic ring body 311 is designed to be smooth and the inner surface to be rough. Specifically, a rough layer is provided on the inner surface of the ceramic ring body 311 and a smooth layer is provided on the outer surface of the ceramic ring body 311.

[0063] A roughened layer is provided on the inner surface of the ceramic ring body 311, which is more conducive to providing a larger specific surface area, increasing the contact area between the ceramic ring and the vapor, and giving phthalic anhydride or other oligomers more opportunities to contact and crystallize on the ceramic ring surface. Due to the good thermal conductivity of ceramics, the smooth layer on the outer surface of the ceramic ring body 311 facilitates liquid flow and achieves reflux after heating.

[0064] In some embodiments, the aspect ratio of the ceramic ring body 311 ranges from 1:2 to 1:3.

[0065] For example, the outer diameter of the ceramic ring body 311 can be 37mm, the aperture of the ceramic ring body 311 can be 35mm, and the length of the ceramic ring body 311 can be 15mm. The preferred aspect ratio of the ceramic ring is about 1:2.5.

[0066] The above-mentioned aspect ratio design helps to form a good airflow channel inside the cylinder 10, and will not cause excessive airflow resistance due to excessively long ceramic rings, which would affect the flow of steam in the cylinder 10. This ensures that the steam containing phthalic anhydride can flow smoothly between the ceramic rings, thereby improving the efficiency of capturing phthalic anhydride.

[0067] Furthermore, the thickness of the ceramic ring body 311 is designed to be relatively thin (generally not exceeding 2mm). On the one hand, the inner diameter of 35mm provides sufficient space for phthalic anhydride vapor to enter the interior of the ceramic ring body 311. Additionally, due to the excellent heat transfer properties of ceramics, the interior of the ceramic ring body 311 can cool rapidly, providing a suitable crystallization environment for the phthalic anhydride, which is beneficial for its crystallization and growth on the inner wall of the ceramic ring. On the other hand, when the ceramic ring body 311 needs to be heated to allow the crystallized phthalic anhydride to flow back to the reactor 100, the 35mm inner diameter ensures that heat is evenly transferred to the interior of the ceramic ring body 311. This allows the crystallized phthalic anhydride to smoothly detach from the inner wall of the ceramic ring body 311 at a suitable temperature and flow back to the polyester reactor 100 along the internal channels of the ceramic ring body 311.

[0068] In some embodiments, one end of the cylinder 10 is connected to an inlet flange 40 and the other end is connected to an outlet flange 50. Both the inlet flange 40 and the outlet flange 50 include a flange body 41 and a central orifice plate 42 located at the center of the flange body 41.

[0069] As can be seen, the integrated flange + center orifice plate structure combines the traditional flange and flow limiting element into one, eliminating the need for additional blind plate or orifice plate installation, shortening the axial dimension, and reducing the number of leakage points; at the same time, the center orifice plate 42 forms a uniformly distributed initial flow field at the inlet end, weakening the direct impact of high-speed steam on the ceramic ring array 30, reducing local blockage and wear of the ceramic ring body 311, and forming back pressure at the outlet end, allowing the gas phase to remain fully in the ceramic ring layer, improving condensation / capture efficiency.

[0070] In addition, during maintenance, only the flange needs to be removed to replace or clean the ceramic ring unit 31. The orifice plate is removed simultaneously with the flange, without the need to remove the bolts or gaskets separately, thus shortening maintenance time and reducing labor intensity.

[0071] In some embodiments, the condensation reflux device further includes an orifice plate septum 60, which is made of polytetrafluoroethylene. The orifice plate septum 60 is disposed in the cylinder 10 and contacts the ceramic ring array 30 for positioning the ceramic ring array 30.

[0072] Meanwhile, the orifice plate septum 60 and the center orifice plate 42 of the inlet flange 40 are spaced apart, and a condensation reflux space is formed between the orifice plate septum 60 and the center orifice plate 42 of the inlet flange 40 for the condensation reflux of the polyester synthesis process medium.

[0073] Specifically, the orifice plate diaphragm 60 is installed in the pipe, with a 30mm space between it and the center orifice plate 42 of the inlet flange 40. This space is used for steam condensation and reflux.

[0074] In this way, an orifice plate septum 60 is added 30mm downstream of the central orifice plate 42 at the inlet flange 40, forming a fixed-volume condensation reflux chamber between the septum 60 and the central orifice plate 42. High-temperature vapor containing sublimates is throttled by the central orifice plate 42, then suddenly expands and decelerates within the chamber, making full contact with the cold wall surface, achieving the first efficient condensation. The condensate flows back to the reaction system along the chamber wall under gravity, recovering the acid anhydride / alcohol raw materials and preventing them from continuing to rise and clogging the ceramic ring array 30. The narrow 30mm spacing ensures minimal chamber volume, sufficient steam residence time for one condensation without stagnation or accumulation, a significant temperature gradient within the chamber, and higher condensation efficiency than traditional long straight cylinder sections. Simultaneously, this size accommodates assembly and disassembly space without increasing the overall structural length. The orifice plate septum 60 itself has a throttling effect, and after secondary rectification, it can further homogenize the airflow distribution entering the ceramic ring layer, reducing local high-speed scouring and channeling phenomena, and extending the service life of the ceramic ring array 30. The cavity and the ceramic ring layer are spatially separated, and the condensate return path is short and independent, which avoids the condensate from carrying solid particles into the ceramic ring array 30 again, keeps the surface of the ceramic ring array 30 clean, and the overall pressure drop increases slowly, enabling long-term online operation.

[0075] In some embodiments, the jacket 20 is provided with a first connector 70 at one end near the inlet flange 40 and a second connector 80 at one end near the outlet flange 50. Both the first connector 70 and the second connector 80 are connected to the outer cavity 21. The first connector 70 is used to introduce the refrigerant and discharge the heating medium, and the second connector 80 is used to introduce the heating medium and discharge the refrigerant.

[0076] Specifically, the first connector 70 and the second connector 80 are welded to the jacket 20, and the first connector 70 and the second connector 80 are tightly connected to the pipeline through flanges. In this way, the opening and closing of the valves can be remotely controlled by the DCS process, which effectively reduces the accumulation of acid and anhydride crystals inside the cylinder 10 and ensures the smooth flow of the condenser 300 or the distributor 200.

[0077] For example, in a polyester synthesis production equipment, the condenser 300 is turned on to heat water vapor, causing the solid phthalic anhydride or reactants in the condenser 300 to sublimate (from solid to gas). At the same time, the fractionator 200 is turned on to cool down. When the gaseous phthalic anhydride or reactants flow to the fractionator 200, they are liquefied upon cooling and flow into the reactor 100.

[0078] If the above effect is not satisfactory, an independent jacket can be added to the pipeline between the condenser 300 and the distributor 200. By controlling the temperature of the water vapor in the jacket, the gaseous phthalic anhydride or reactant that escapes to the condenser 300 can flow to the distributor 200.

[0079] It should be noted that this application primarily addresses the issue of acid and anhydride crystals in the fractionator 200 and condenser 300 by introducing a heat medium based on the melting points of the acid and anhydride. Furthermore, steam was chosen as the heat medium after considering environmental friendliness, economy, and applicability. A reasonable reaction process was designed, and the opening and closing of valves were remotely controlled via a DCS system to effectively reduce the accumulation of acid and anhydride crystals, ensuring unobstructed flow in the condenser 300 and fractionator 200. In the initial stage of the reaction, when phthalic anhydride and oligomers need to condense in the fractionator 200, cold water is introduced through the first connector 70 of the jacket 20 and discharged through the second connector 80 via the DCS system. In the middle and later stages of the reaction, when phthalic anhydride and oligomers need to exit the fractionator 200, steam is introduced through the second connector 80 and discharged through the first connector 70 via the DCS system.

[0080] As can be seen from the above, existing technologies offer various solutions to the blockage problem of the fractionating coil 200 or condenser 300 in polyester synthesis production equipment. However, most of these solutions have limitations, such as the inability to achieve complete online processing, the need for manual or mechanical intervention, and the reliance on methods like ethylene glycol thermal dissolution, physical crushing, or scraping for cleaning and unblocking. This application modifies the structure of the fractionating coil 200 or condenser 300 to achieve anhydride crystallization and oligomer enrichment. Simultaneously, it incorporates DCS remote control, introducing steam to melt the anhydride oligomers, which then flow into the reaction vessel 100. This not only ensures accurate material proportioning and unrestricted reaction extent but also provides higher targeting, automation, and intelligence.

[0081] Specifically, the condensation reflux device of this application not only completely solves the clogging problem of the fractionator 200 / condenser 300, ensuring the accuracy of material proportioning and the sufficiency of reaction, and avoiding the drawbacks of polymer imbalance and structural distortion caused by raw material loss, but also achieves full automation and intelligence in the processing, improving production efficiency and safety. At the same time, this application also emphasizes environmental protection, ensuring that the medium switching process does not cause pollution to the environment or water bodies, and that in the event of a puncture in the condensation equipment, leaked substances will not contaminate the synthesized product, or can be effectively separated after entering the synthesized product, thereby comprehensively improving the sustainability, stability, and environmental friendliness of the polyester synthesis production process.

[0082] This application provides a polyester synthesis production equipment, including the condenser reflux device described in the above specific embodiments. The polyester synthesis production equipment also includes a reactor 100 and a water collector 400. The condenser reflux device can be a separator 200, which is mainly used to separate the water and oligomers generated in the reaction. The separator 200 controls the condensation temperature to condense water vapor into liquid water and discharge it, while the oligomers are condensed and refluxed back to the reactor 100 to continue participating in the reaction, reducing raw material loss. Alternatively, the condenser reflux device can be a condenser 300, which is mainly used to collect the oligomers escaping during the polycondensation reaction stage. Both the separator 200 and the condenser 300 work together to ensure the smooth progress of the polyester synthesis reaction. Other parts of the polyester synthesis production equipment can be referred to in related technologies, and will not be elaborated upon here.

[0083] During polyester synthesis in the polyester reactor 100, in the initial stage of the reaction, excessively high local or heating temperatures may cause phthalic anhydride and oligomers to reach their boiling points. This results in volatiles entering the fractionating condenser 200 and condenser 300, leading to an imbalance in the material ratio and affecting the final product or product quality. At this point, the cooling water supply to the fractionating condenser 200 is activated using a DSC controller. The cooling water enters through the first connector 70 and flows out through the second connector 80, rapidly cooling the steam through the ceramic ring array 30. This allows the phthalic anhydride or oligomers to condense on the inner surface of the ceramic ring array 30, subsequently crystallizing and accumulating.

[0084] When condenser 300 needs to be cleaned, use the DSC controller to turn on the steam in condenser 300, let it enter from the second connector 80 and flow out from the first connector 70, and heat the phthalic anhydride or oligomers that escape from the separator 200 as much as possible, and let them evaporate back into the separator 200, thereby achieving online cleaning of condenser 300.

[0085] Once the phthalic anhydride in the reactor 100 is completely consumed, or the ceramic ring of the separator 200 is blocked, the steam in the separator 200 is turned on using the DSC controller. Steam is introduced through the second connector 80 and flows out through the first connector 70, allowing the phthalic anhydride or oligomer in the separator 200 to flow back into the reactor 100, thereby achieving online cleaning of the separator 200, while the steam in the jacket 20 of the condenser 300 remains unchanged.

[0086] After the phthalic anhydride or oligomer in the fractionator 200 has finished refluxing, use the DSC controller to shut off the water vapor in the jacket 20 of the fractionator 200, while the water vapor in the jacket 20 of the condenser 300 remains unchanged.

[0087] When the reaction reaches the middle and late stages, the reactor 100 is evacuated, and the cooling water in the jacket 20 of the condenser 300 is turned on using the DSC controller. The cooling water is introduced from the first connector 70 and flows out from the second connector 80, so that the product water in the polyester reaction process is condensed and flows into the water collector 400 until the reaction ends.

[0088] The beneficial effects of adopting the above settings include at least the following:

[0089] 1. Significantly Improved Corrosion Resistance: During polyester synthesis, the volatilization of acids and anhydrides can corrode the bottom orifice plate of the shrinkage unit 200 and the inner layer of the cylinder 10, easily leading to perforation and leakage. The shrinkage unit 200 of this application adopts a packed structure, directly connected to the reactor body, effectively preventing shell-side leakage after the bottom orifice plate is perforated. Simultaneously, the added PTFE orifice plate septum 60 reduces direct contact between metal components, preventing packing material from leaking into the reactor 100 even if the metal orifice plate is perforated, thus significantly enhancing the acid and anhydride corrosion resistance of the shrinkage unit 200.

[0090] 2. Environmentally Friendly and Economical Heat Treatment Medium: This application uses steam as the heat treatment medium, which is a very common heat medium in chemical production. Experiments have verified that acid anhydride mixed crystals can melt at 100-140℃, while the saturation temperature of steam at 0.5MPa is approximately 151.83℃, fully meeting the melting requirements. Compared with the commonly used solvent ethylene glycol, steam is more environmentally friendly, economical, and has wider applicability.

[0091] 3. Improve reaction efficiency: By introducing hot steam, the volatile acid anhydride crystals can be remelted and re-participated in the polyester synthesis reaction, which effectively improves the utilization rate of raw materials and thus enhances reaction efficiency.

[0092] 4. Ensuring Production Safety and Efficiency: This application can solve the pressure buildup problem caused by blockage in the reactor 100 equipment under closed conditions without shutting down the machine, effectively preventing safety accidents during the reaction process. Simultaneously, it precisely controls the reaction process, keeping the reaction time within a reasonable range, shortening the overall reaction time and improving production efficiency.

[0093] 5. Reduced Cleaning Difficulty: Traditional methods make cleaning cumbersome and difficult after blockages in the distributor 200 and condenser 300. This application, through online cleaning technology, significantly reduces the difficulty of post-cleaning, decreases the workload of manual disassembly and maintenance, and improves the convenience of equipment maintenance.

[0094] 6. Achieve Efficient Online Cleaning: This application enables online cleaning of the fractionating condenser 200 and condenser 300 without interrupting the production process. At different stages of the polyester synthesis reaction, valves can be remotely controlled via DCS to flexibly switch the heat medium (cold water or steam) according to actual needs. In the initial stage of the reaction, cold water is used to condense and crystallize the phthalic anhydride and oligomers on the ceramic rings; in the middle and later stages of the reaction, steam is introduced to melt the crystals and return them to the reactor 100. This online cleaning method not only promptly resolves blockage issues but also avoids production stoppages caused by equipment cleaning, greatly improving the continuity and stability of production.

[0095] It should be noted that in this specification, relational terms such as first and second are used only to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities.

[0096] The condensation reflux device and polyester synthesis production equipment provided in this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the solution and core ideas of this application. It should be noted that those skilled in the art can make several improvements and modifications to this application without departing from the principles of this application, and these improvements and modifications also fall within the protection scope of this application.

Claims

1. A condensation reflux device, characterized in that, include: The cylindrical body has an inner cavity for containing the medium used in the polyester synthesis process; A jacket is provided on the outer periphery of the cylinder, forming an outer cavity that is separated from the inner cavity. The outer cavity is used to introduce a cooling medium or a heating medium. The ceramic ring array, located in the inner cavity and distributed along the axial direction of the cylinder, is configured to: cause the polyester synthesis process medium to condense and accumulate when a cooling medium is introduced into the outer cavity, and cause the polyester synthesis process medium to be heated and refluxed when a heating medium is introduced into the outer cavity.

2. The condensation reflux device as described in claim 1, characterized in that, The ceramic ring array comprises several layers of ceramic ring units distributed along the axial direction of the cylinder, and any one of the ceramic ring units has a honeycomb structure.

3. The condensation reflux device as described in claim 2, characterized in that, The ceramic ring units in any two adjacent layers are arranged in an alternating pattern.

4. The condensation reflux device as described in claim 2, characterized in that, Each of the ceramic ring units includes a plurality of ceramic ring bodies, the inner surface of the ceramic ring body is provided with a rough layer, and the outer surface of the ceramic ring body is provided with a smooth layer.

5. The condensation reflux device as described in claim 4, characterized in that, The aspect ratio of the ceramic ring body is in the range of 1:2 to 1:

3.

6. The condensation reflux device as described in claim 1, characterized in that, One end of the cylinder is connected to an inlet flange, and the other end is connected to an outlet flange. Both the inlet flange and the outlet flange include a flange body and a central hole plate located at the center of the flange body.

7. The condensation reflux device as described in claim 6, characterized in that, The condensation reflux device also includes an orifice plate septum, which is disposed in the cylinder and contacts the ceramic ring array to position the ceramic ring array.

8. The condensation reflux device as described in claim 7, characterized in that, The orifice plate septum is spaced apart from the central orifice plate of the inlet flange, and a condensation reflux space is formed between the orifice plate septum and the central orifice plate of the inlet flange for condensation reflux of the polyester synthesis process medium.

9. The condensation reflux device as described in claim 6, characterized in that, The jacket is provided with a first connector at the end near the inlet flange and a second connector at the end near the outlet flange. Both the first connector and the second connector are connected to the outer cavity. The first connector is used to introduce the refrigerant and discharge the heating medium, and the second connector is used to introduce the heating medium and discharge the refrigerant.

10. A polyester synthesis production equipment, characterized in that, Includes the condensation reflux device as described in any one of claims 1-9.

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