Polymerization reactor

Abstract

The invention relates to the field of chemical equipment, in particular to a polymerization reactor which comprises a reaction tube, and the reaction tube comprises a top cover, a tube body and a bottom cover. The polymerization reactor further comprises a plurality of cyclone separation tube bundles communicated with the top cover and the bottom cover, each cyclone separation tube bundle comprises a separation section and a conveying section from top to bottom, the separation sections and the conveying sections are connected with each other through tightening sections with the diameters gradually reduced, a material inlet tube communicated with the top cover is arranged at the end of each separation section, and a material outlet tube communicated with the bottom cover is arranged at the end of each conveying section. The material inlet pipe is communicated with the separation section in the tangential direction of the separation section, a separation pipe is further arranged on the separation section, and the center line of the separation pipe coincides with the center line of the separation section. According to the polymerization reactor, reaction heat can be quickly removed, so that the molecular weight of a polymer can be selectively regulated and controlled. In addition, the risk that solid polymer particles block the kettle is avoided, and the conversion rate of the monomer is improved while the dosage of the catalyst is reduced.

Description

Technical Field

[0001] The invention relates to the field of chemical equipment, in particular to a polymerization reactor. Background Art

[0002] Slurry polymerization is an important polymerization method. In this process, monomers are polymerized in a dispersion medium (usually an inert organic solvent or liquid hydrocarbon) under the action of a catalyst, and the resulting polymer is suspended in the dispersion medium in the form of tiny particles to form a slurry system. The polymerization process is generally carried out under appropriate temperature and pressure conditions, and continuous stirring is required to maintain the suspension state of the polymer particles, ensure reaction uniformity and effective heat transfer.

[0003] Butyl rubber is a slurry polymerization reaction of isobutylene and a small amount of isoprene (generally 1.5-4.5% mol) at low temperature (-98℃--80℃) with methyl chloride as a diluent under the action of aluminum chloride or alkyl aluminum catalyst. Isobutylene monomer undergoes polymerization reaction at the active center of the catalyst in the dispersion medium of methyl chloride. The generated butyl rubber exists in the form of suspended particles in the methyl chloride solution, forming a slurry state. The slurry polymerization process can accurately control the molecular weight of butyl rubber by adjusting reaction conditions such as catalyst concentration, reaction temperature, monomer concentration and other factors. At the same time, since the slurry polymerization reaction system is relatively stable and the temperature, pressure and other conditions are easy to control, the quality stability of butyl rubber can be guaranteed. In addition, the butyl rubber particles produced by slurry polymerization are more regular in shape, and the generated particles are more uniform in size, which is conducive to subsequent separation, drying and processing.

[0004] However, the existing equipment for slurry polymerization has the following technical problems: (1) Difficulty in removing heat from the polymerization reaction: The butyl rubber slurry polymerization reaction is an exothermic cationic polymerization reaction, which releases a large amount of heat at the moment of reaction. The amount of heat released during large-scale production is particularly huge. Due to the poor thermal conductivity of the polymer slurry system, it is difficult to dissipate the heat quickly and evenly. Existing polymerization reactors often have deficiencies in heat transfer design. For example, the traditional jacketed heat transfer structure has a limited heat transfer area. At high polymerization reaction rates, it is difficult to meet the demand for timely heat removal, which can easily lead to excessively high local temperatures in the reaction system. Excessive temperatures will not only affect the molecular weight distribution and product quality of the polymer, but may also trigger side reactions, reduce the performance of the polymer, and even cause safety accidents due to temperature runaway.

[0005] (2) Problems of uniform suspension and separation of polymer particles: In the slurry polymerization process, it is crucial to maintain uniform suspension of polymer particles in the dispersion medium. However, as the polymerization reaction proceeds, the particle size of the polymer particles gradually increases and their density also changes. The existing stirring device is difficult to ensure that the particles are always uniformly dispersed throughout the entire reaction cycle, and particle agglomeration or sedimentation is prone to occur. In the separation stage after the reaction, it is also a major challenge to efficiently separate the polymer particles from the slurry system. Existing separation equipment, such as simple filtration devices or sedimentation separators, has problems such as low separation efficiency and large amount of residual polymer particles, which not only affects the yield of the product, but also the residual polymer particles may accumulate inside the equipment, affecting the normal operation of the equipment and increasing the cost and frequency of equipment cleaning and maintenance.

[0006] (3) Difficulties in catalyst dispersion and activity maintenance: Slurry polymerization relies on the action of the catalyst. The degree of uniform dispersion of the catalyst in the dispersion medium directly affects the activity and selectivity of the polymerization reaction. However, in actual operation, the catalyst tends to agglomerate easily, making it difficult to form a uniform distribution of active centers in the entire reaction system. Existing reactors are not perfect in the design of catalyst feed and dispersion systems, and cannot effectively solve this problem, resulting in the inability to fully exert the catalyst activity, increasing the amount of catalyst used and raising production costs.

[0007] For example, the patent with application number CN201310669715.1 discloses a butyl rubber polymerization reactor, including a cylinder, the upper end of the cylinder is connected to an upper pipe box, the lower end is connected to a lower pipe box, and a central cylinder is installed in the center of the cylinder, which is characterized in that a spiral guide plate is installed in the central cylinder, the upper end of the central cylinder is connected to an upper guide cone, and the lower end is connected to a lower guide cone; the lower pipe box is respectively connected to a feed port and a catalyst inlet, and the reaction raw materials enter the lower pipe box from the feed port and are mixed with the catalyst entering from the catalyst inlet, and then enter the lower guide cone and are driven by a stirring transmission system with blades located in the central tube to be fully mixed along the spiral guide plate, and then overflow from the upper guide cone into the heat exchange tube bundle around the central tube to exchange heat with the coolant filled on the outside of the heat exchange tube bundle. However, the patent does not propose a good solution to the above-mentioned technical problems such as the difficulty in removing heat from the polymerization reaction and the difficulty in separating polymer particles.

[0008] In summary, the existing slurry polymerization process has many defects in the polymerization reactor, which limits the further development and optimization of the slurry polymerization process. There is an urgent need for a new polymerization reactor design that can effectively overcome the above difficulties. Summary of the invention

[0009] The present invention aims to overcome the defects of the polymerization reactor in the prior art, such as difficulty in removing the polymerization reaction heat and difficulty in separating the polymer particles, and provides a polymerization reactor to overcome the above-mentioned shortcomings.

[0010] To achieve the above-mentioned purpose, the present invention is implemented by the following technical solutions: The present application first provides a polymerization reactor, comprising a reaction tube, wherein the reaction tube is provided with a material inlet for introducing reaction materials and a slurry outlet for discharging reaction materials, the reaction tube comprises a top cover, a tube body and a bottom cover, the three of which are separated from each other by a partition, and the bottom cover is provided with a turbine device for driving material mixing and flow, A guide cylinder connected to the bottom cover is arranged at the center of the tube body, and a plurality of central tube bundles arranged in an array and connected to the top cover are extended upward from the top of the guide cylinder. A refrigeration jacket is formed between the inner wall of the tube body, the central tube bundle and the guide cylinder to pass a cooling medium to remove the reaction heat inside the central tube bundle; The polymerization reactor further comprises a plurality of cyclone separation tube bundles connected to the top cover and the bottom cover, so that a circulation passage for the reaction material to flow is formed between the bottom cover, the guide tube, the central tube bundle, the top cover and the cyclone separation tube bundle; The cyclone separation tube bundle comprises a separation section and a conveying section from top to bottom, the separation section and the conveying section are connected to each other via a tightening section with a gradually decreasing diameter, a material inlet pipe connected to the top cover is provided at the end of the separation section, the material inlet pipe is connected to the separation section along the tangent direction of the separation section, and a separation tube connected to a storage device for storing solid colloid particles obtained by the reaction is also provided on the separation section, and the center lines of the separation tube and the separation section coincide with each other.

[0011] As described in the background technology, a large amount of heat is generated during the free radical polymerization or ionic polymerization of polymer monomers. Excessive heat accumulation will cause the local temperature of the reaction system to be too high, thereby affecting the molecular weight distribution and product quality of the polymer, and may even cause safety accidents due to temperature runaway. Therefore, the temperature control of the polymerization reactor seriously affects the performance and safe production of the polymer.

[0012] Therefore, compared with the polymerization reactor in the prior art, the polymerization reactor in the present application is characterized by targeted improvements in thermal management and thermal control during the polymerization reaction process. The main features include the following points: First, the polymerization reactor in the prior art is usually equipped with only one guide tube at the center, and the polymerization monomer and the catalyst contact in the guide tube to cause the polymerization reaction. However, due to the large diameter of the guide tube, its specific surface area is relatively small, so the contact area between the guide tube and the cooling medium is small, resulting in low efficiency of the cooling medium in removing the reaction heat.

[0013] In addition to a guide tube at the initial stage of the material, the present application also provides a plurality of central tube bundles arranged in an array and interconnected with the top cover at the top of the guide tube. Since the diameter of the central tube bundle is much smaller than the diameter of the guide tube, the specific surface area of ​​the central tube bundle is larger than that of the guide tube, so that the contact area between the central tube bundle and the cooling medium is greatly increased, thereby effectively improving the cooling effect of the cooling medium.

[0014] Secondly, after the materials in the polymerization reactor are polymerized, they can form small-sized solid polymer particles. These polymer particles are mixed in the polymerization reaction monomers and diluents, so that slurry is formed in the polymerization reactor. However, this process will bring the following risks: (1) These polymer particles are easy to adhere to the inner wall of the pipeline of the polymerization reactor, resulting in the risk of blockage of the polymerization reactor. (2) Due to the poor thermal conductivity of polymer particles, the heat dissipation effect of the materials inside the polymerization reactor will be significantly reduced as the reaction proceeds. (3) In addition, due to the presence of solid polymer particles, the monomer concentration and catalyst concentration inside the reactor will gradually decrease as the reaction proceeds, causing the polymerization reaction efficiency to drop significantly over time.

[0015] Therefore, another difference between the present application and the traditional polymerization reactor is that the present application also adds a group of cyclone separation tube bundles in the polymerization reactor, which can form a circulation path for the flow of reaction materials between the bottom cover, the guide tube, the central tube bundle, the top cover and the cyclone separation tube bundle. Therefore, after the material reacts from the guide tube and the central tube bundle, it will enter the cyclone separation tube bundle. Since the cyclone separation tube bundle contains a separation section, the solid polymer particles and the liquid phase system in the material enter the separation section along the tangent direction of the separation section. These materials can be separated under the separation effect of the cyclone separation tube bundle, and the solid polymer particles with a smaller density can be accumulated on the top of the separation section, and then enter the storage device along the separation tube on the top of the separation section for storage. The liquid phase system obtained by separation is transported downward to the bottom cover, the guide tube, and the central tube bundle in turn due to its large density, so that further polymerization reaction occurs.

[0016] After solid-liquid separation, large molecular weight solid polymer particles can be separated, effectively avoiding the risk of kettle blockage caused by large molecular weight and significantly improving the single kettle operation efficiency. At the same time, a large amount of diluent solution can be recycled, which not only reduces the energy consumption of the polymerization kettle system, but also effectively improves the monomer concentration and catalyst concentration of the polymerization reaction, thereby improving the single kettle production efficiency, achieving the effect of reducing the amount of catalyst and increasing the monomer conversion rate. In addition, solid-liquid separation can separate solid polymer particles with low thermal conductivity, greatly enhancing the thermal conductivity of the overall material, which is conducive to the selective regulation of molecular weight. By coordinating with polymerization temperature control, flexible adjustment of polymer molecular weight can be achieved to meet diverse production needs.

[0017] Preferably, the contraction section of the cyclone separation tube bundle is composed of a plurality of mutually connected frustum tubes, and the cone angles of the frustum tubes decrease in sequence from top to bottom.

[0018] In the present application, the contraction section is composed of a number of interconnected frustum tubes, and the cone angle decreases from top to bottom. This structure makes the channel gradually narrower when the material flows through the contraction section, and due to the change in the cone angle, the flow direction of the material will change more drastically. In the cyclone separation process, this structure will enhance the intensity of the cyclone. When the material enters the contraction section after generating a cyclone in the separation section, the cyclone will be further strengthened as the channel shrinks and the flow direction changes, thereby generating a greater centrifugal force. For solid-liquid separation, a greater centrifugal force is conducive to more effectively throwing solid particles (solid polymers) to the edge of the separation section. Under the action of the enhanced centrifugal force, they can gather faster to the wall of the separation section tube and be better separated from the liquid medium.

[0019] In addition, the structure with gradually decreasing cone angle can achieve finer separation of solid particles of different particle sizes. During the cyclone process, solid particles with larger particle sizes will first move toward the tube wall under the action of centrifugal force. As the channel further shrinks and the cyclone intensity increases, solid particles with smaller particle sizes will gradually be separated. This structure can separate particles by layer according to particle size, avoiding incomplete separation due to differences in particle size.

[0020] The connection structure of the truncated cone tube makes the flow of materials more orderly. Compared with a simple suddenly contracted channel, this gradual structure can reduce the disorder and turbulence of the flow. In cyclone separation, a stable flow state helps to maintain the stability of the cyclone, thereby ensuring the consistency of the separation effect. If the flow is too turbulent, it may cause the separated solid particles and liquid to remix, and this contraction section structure composed of truncated cone tubes can effectively avoid this situation, making the solid-liquid separation process more stable and reliable.

[0021] Preferably, the cyclone separation tube bundle is disposed inside the tube body of the reaction tube and is arranged in an array on the outer circumference.

[0022] Placing the cyclone separation tube bundle inside the tube of the reaction tube can make full use of the space inside the reaction tube. Compared with placing the separation device outside the reaction tube, this built-in method avoids occupying a large amount of additional external space, making the structure of the entire polymerization reactor more compact. In the chemical production process, a compact equipment layout helps to reduce the floor space, especially in large-scale production workshops or chemical plants with dense equipment. This advantage is particularly obvious.

[0023] The cyclone separation tube bundle arranged in an array on the inner periphery of the tube body can be easily integrated with other components in the reaction tube. For example, it can cooperate well with the circulation path of the reaction tube, so that the reaction materials can directly enter the cyclone separation tube bundle for separation after the reaction is completed, without the need for a complex pipeline transportation system to transfer the reaction materials to the external separation equipment. This integrated design simplifies the process flow, reduces the energy loss and possible leakage risk of materials during the transmission process, and also facilitates the operation and control of the entire polymerization reaction and separation process.

[0024] Since the cyclone separation bundle is located inside the reaction tube, it can work in conjunction with the temperature control mechanism inside the reaction tube. In the slurry polymerization process, the control of the reaction temperature is crucial, and this layout allows the cyclone separation bundle to be in a temperature environment close to the reaction area. When the reaction materials need to be separated, their temperature can be well connected with the reaction temperature, avoiding the change of material properties or adverse effects on the separation effect caused by sudden temperature changes. For example, some polymers may crystallize or change in viscosity when the temperature changes greatly, and this internal layout helps to maintain relatively stable temperature conditions, which is conducive to improving the effect of solid-liquid separation.

[0025] Preferably, a slurry interlayer for gathering solid colloid particles flowing out of the separation tube at the upper end of the cyclone separation tube bundle is provided on the top of the top cover, and the slurry interlayer is connected with the slurry outlet.

[0026] Preferably, the cyclone separation tube bundle is arranged outside the reaction tube and is arranged in parallel with each other to form a cyclone separation tube group.

[0027] When the cyclone separation tube bundle is arranged outside the reaction tube, maintenance and overhaul work will become more convenient. During the operation of the polymerization reactor, the cyclone separation tube bundle may be blocked, worn or otherwise malfunction due to long-term contact with the reaction material. By setting it outside, the operator can inspect, repair or replace parts more directly without going deep into the reaction tube for complicated operations. Secondly, the cyclone separation tube groups connected in parallel provide a more flexible operation mode. During the production process, part of the cyclone separation tube bundle can be flexibly selected to be enabled or disabled according to the actual reaction situation and separation requirements. Moreover, this parallel cyclone separation tube group forms a modular structure. In the design and manufacturing process of the reactor, the modular design is conducive to standardized production and assembly. Each cyclone separation tube bundle can be regarded as an independent module, which can be batch manufactured during the production process and then combined in parallel according to specific process requirements. This not only improves production efficiency, but also makes it easy to flexibly increase or decrease the number of cyclone separation tube bundles according to different production scales and process requirements, thereby enhancing the adaptability and scalability of the reactor. Finally, the cyclone separation tube bundle placed outside the reaction tube will not cause excessive interference to the reaction environment inside the reaction tube. During the reaction process, factors such as fluid mechanics and temperature distribution inside the reaction tube are crucial to the smooth progress of the polymerization reaction. Placing the cyclone separation device outside can avoid its structure from having an adverse effect on the material flow, mixing effect, and temperature field inside the reaction tube, thereby ensuring the stability and reliability of the reaction process.

[0028] Preferably, the exterior of the cyclone separation tube group is sheathed in a cooling jacket through which a cooling medium can flow to remove the reaction heat inside the cyclone separation tube bundle.

[0029] Preferably, a booster pump for conveying reaction materials is provided between the cyclone separation tube group and the reaction tube.

[0030] Preferably, a nose cone is provided at the center of the bottom cover for guiding the material to flow toward the guide tube, the nose cone extends upward to the inside of the guide tube, and the turbine device is provided at the top of the nose cone.

[0031] In the present application, the nose cone is located at the center of the bottom cover and extends upward to the inside of the guide tube. Its main function is to guide the material to flow in the guide tube. In a polymerization reactor, the flow path and method of the material have a great influence on the reaction efficiency and uniformity. The shape of the nose cone can make the material discharged from the turbine device converge more concentratedly to the guide tube, ensuring that the material enters the guide tube in an orderly manner, thereby forming a stable circulation flow in the reaction tube. This guiding effect can avoid disordered diffusion or local accumulation of materials in the bottom cover area, so that the material can participate in the reaction process more efficiently.

[0032] The turbine device is located at the top of the nose cone, which helps to enhance the efficiency of the turbine device. The main function of the turbine device is to drive the mixing and flow of materials. When it is located at the top of the nose cone, it can better use the power generated by its rotation to push the materials. The nose cone can serve as a guide structure to make the materials discharged from the turbine device flow in a specific direction, thereby increasing the flow rate and directionality of the materials.

[0033] This combination of nose cone and turbine device helps to improve the fluid mechanics performance in the reaction tube. In slurry polymerization, good fluid mechanics conditions are crucial for the reaction. By guiding the material into the guide tube through the nose cone, combined with the power of the turbine device, a relatively stable circulation flow pattern can be formed in the reaction tube, reducing the occurrence of turbulence and dead zones. Stable circulation flow can enable the reaction materials to fully contact in all areas, promote uniform mixing of monomers and catalysts, and facilitate the uniform progress of the polymerization reaction. It also helps the transfer and exchange of heat and has a positive effect on the control of the reaction temperature.

[0034] Preferably, a lower flow guide for enhancing the mixing effect of the reaction materials is further provided on the inner wall of the flow guide cylinder, and the fluid flow guide extends downward to the inner space of the bottom cover.

[0035] The lower deflector arranged on the inner wall of the deflector tube and extending downward to the inner space of the bottom cover has many important functions: First, further strengthen the mixing of materials. In the polymerization process, the full mixing of the reaction materials is a key factor to ensure the uniformity and efficiency of the reaction. The lower deflector can conduct secondary guidance and disturbance on the flow of materials, so as to improve the flow stratification or local stagnation that may have existed. For example, when the material flows from the turbine device to the flow guide tube through the nose cone, the lower deflector can change the flow direction and flow velocity distribution of the material, so as to promote more complete mixing of materials at different positions and in different states, so that the monomers and catalysts and other reaction components can contact each other more evenly, thereby improving the rate and uniformity of the polymerization reaction, which is conducive to the production of polymer products with more stable quality and more consistent performance.

[0036] Secondly, optimize heat transfer and distribution. Since slurry polymerization reactions are accompanied by heat generation, good heat transfer is essential for reaction control. The lower guide indirectly affects the heat transfer path and efficiency in the reaction system by adjusting the material flow. It enables the material to form a more complex and orderly flow circuit in the internal space of the guide tube and the bottom cover, enhances the heat exchange effect, avoids the formation of local overheating or overcooling areas, and makes the temperature distribution in the reaction system more uniform, which is conducive to the stable polymerization reaction under suitable temperature conditions, and reduces problems such as side reactions or product quality fluctuations caused by uneven temperature.

[0037] Furthermore, it promotes the recycling of materials in the bottom cover area. The lower deflector extends to the internal space of the bottom cover, which can effectively drive the materials in the bottom cover area to participate in the overall circulation flow. During the reaction process, some materials may be deposited or flow slowly near the bottom cover. The lower deflector can re-involve these materials into the main fluid, improve the utilization rate of the materials, reduce the residue and accumulation of materials at the bottom of the reactor, and reduce the adverse effects on subsequent reactions and equipment cleaning and maintenance. At the same time, it also helps to ensure the continuity and stability of the reaction process, and improve the overall operating performance and production efficiency of the polymerization reactor.

[0038] Preferably, the material inlet includes a catalyst inlet and a polymerization feed inlet arranged at the bottom cover; The bottom cover is also provided with a driving device for driving the turbine device to move; The tube body is provided with a coolant inlet and a coolant outlet for the cooling medium to enter and flow out; The top cover is also provided with an upper deflector for guiding the slurry obtained by the reaction.

[0039] Therefore, this application has the following beneficial effects: (1) In the present application, the flow channel of the material in the polymerization reactor is specifically designed, so that the reaction heat in the polymerization reactor can be effectively removed, thereby improving the product quality of the polymer and avoiding safety accidents caused by thermal runaway; (2) The present application sets a cyclone separation tube bundle capable of separating solid polymer particles in the polymerization reactor, thereby avoiding the risk of solid polymer particles blocking the reactor and improving the single reactor operation efficiency. At the same time, it can also effectively increase the polymerization reaction monomer concentration and catalyst concentration, thereby reducing the amount of catalyst used and improving the monomer conversion rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a structural diagram of embodiment 1 of the present invention.

[0041] Figure 2 It is a schematic diagram of the structure of the cyclone separation tube bundle in the present invention.

[0042] Figure 3 It is a schematic diagram of the specific structure of the separation section and the contraction section of the cyclone separation tube bundle in the present invention.

[0043] Figure 4 It is a top view of the cyclone separation tube bundle in the present invention.

[0044] Figure 5 This is a schematic diagram of the structure of Example 2 of the present invention.

[0045] Wherein: reaction tube 1, material inlet 10, slurry outlet 20, top cover 30, slurry interlayer 31, upper guide 32, tube body 40, guide tube 41, central tube bundle 42, refrigeration jacket 43, cyclone separation tube bundle 44, separation section 441, conveying section 442, contraction section 443, material inlet pipe 444, separation tube 445, frustum tube 446, booster pump 447, cyclone separation tube group 45, cooling jacket 46, lower guide 47, coolant inlet 48, coolant outlet 49, bottom cover 50, turbine device 60, nose cone 61, turbine 62, drive device 63, storage device 70. DETAILED DESCRIPTION

[0046] The present invention is further described below in conjunction with specific embodiments. Those of ordinary skill in the art will be able to implement the present invention based on these descriptions. In addition, the embodiments of the present invention involved in the following description are generally only embodiments of a part of the present invention, rather than all embodiments. Therefore, based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work should fall within the scope of protection of the present invention.

[0047] Example 1 like Figure 1 As shown, this embodiment provides a polymerization reactor, including a reaction tube 1, wherein the reaction tube includes a bottom cover 50, a tube body 40 and a top cover 30 from bottom to top.

[0048] Among them, the bottom cover 50 is provided with a material inlet 10 for introducing reaction materials, and the material inlet 10 includes a catalyst inlet 12 for introducing catalyst and a polymerization feed port 11 for introducing polymerization monomers. The catalyst introduced from the catalyst inlet 12 and the polymerization monomer introduced from the polymerization feed port 11 are mixed and transported through a turbine device 60 arranged at the bottom of the bottom cover.

[0049] A guide tube 41 connected to the bottom cover is provided at the center of the tube body 40. The catalyst and the polymerization monomer are mixed in the guide tube 41 under the impetus of the turbine device 60. In order to achieve a better mixing effect, in some preferred embodiments, a lower guide 47 for enhancing the mixing effect of the reaction materials is also provided in the guide tube 41. In order to ensure the full mixing of the reaction materials and the uniformity of the reaction, and to avoid the possible flow stratification or local stagnation, the lower guide 47 extends downward to the inner space of the bottom cover. The moment the reaction monomer contacts the catalyst, the reaction monomer can undergo a polymerization reaction, and a large amount of reaction heat will be generated in this process. In order to effectively remove this reaction heat, in this embodiment, a plurality of central tube bundles 42 arranged in an annular symmetrical array are extended upward from the top of the guide tube 41, and the central tube bundle 42 is connected to the top cover 30. Since the diameter of the central tube bundle 42 is much smaller than the diameter of the guide tube 41 , the specific surface area of ​​the central tube bundle 42 is larger than that of the guide tube 41 , so that the heat dissipation effect of the central tube bundle 42 is more excellent.

[0050] In order to help the central tube bundle 42 dissipate heat faster, a refrigeration jacket 43 is formed between the inner wall of the tube body 40, the central tube bundle 42 and the guide tube 41 for passing a cooling medium to remove the reaction heat inside the central tube bundle 42. The cooling medium used for heat conduction in the refrigeration jacket 43 can be ethylene at -98°C, so as to quickly remove the reaction heat inside the central tube bundle 42.

[0051] In some preferred embodiments, in order to conveniently introduce cooling medium into the refrigeration jacket 43, a coolant inlet 48 for introducing cooling medium is provided at the bottom of the tube body 40, and a coolant outlet 49 is provided at the top of the tube body 40. Therefore, when cooling medium, such as ethylene at -98°C, is introduced from the bottom, it can remove the reaction heat on the surface of the central tube bundle 42, and then the heated or vaporized cooling medium flows out from the coolant outlet 49 located at the top.

[0052] After the reaction material is polymerized in the central tube bundle 42, a large number of small-sized solid polymer particles will be formed. These small-sized solid polymer particles can be mixed with diluents such as methyl chloride and unreacted polymer monomers to form a slurry mixture. These mixtures enter the top cover 30 upward along the central tube bundle 42, and the top of the top cover 30 is provided with a slurry outlet 20 for discharging solid polymer particles in the reaction material. However, at this time, the material inside the top cover 30 also contains a large number of unreacted polymer monomers, so these polymer monomers must be refluxed to the central tube bundle 42 for further polymerization. Therefore, in this embodiment, a cyclone separation tube bundle 44 arranged in an annular shape is also provided around the outside of the central tube bundle 42, and the top and bottom of the cyclone separation tube bundle 44 are respectively connected to the top cover 30 and the bottom cover 50, so that a circulation passage for the flow of reaction materials is formed between the bottom cover 50, the guide tube 41, the central tube bundle 42, the top cover 30 and the cyclone separation tube bundle 44.

[0053] Further integration Figure 2 In order to prevent the small-sized solid polymer particles obtained by polymerization from flowing back into the central tube bundle 42 again, thereby adhering to the inner wall of the pipeline of the polymerization reactor and causing the polymerization reactor to be blocked. The cyclone separation tube bundle 44 includes a separation section 441 and a conveying section 442 from top to bottom. The separation section 441 is used to separate the solid polymer particles in the mixed material, and the conveying section 442 is used to convey the separated unreacted polymer monomers to the central tube bundle 42.

[0054] like Figure 3 as well as Figure 4 As shown, in order to achieve the separation of solid polymer particles in the mixed material, in a preferred scheme of the present embodiment, a material inlet pipe 444 connected to the top cover is provided at the end of the separation section 441, wherein the material inlet pipe 444 is connected to the separation section 441 along the tangential direction of the separation section 441, so that the material can generate centrifugal force when entering the separation section 441 of the cyclone separation tube bundle 44, thereby being separated under the action of the centrifugal force, wherein the solid polymer particles with a smaller density can be accumulated on the top of the separation section 441, and the liquid phase system obtained by separation has a larger density, so the liquid phase system will be transported downward to the bottom cover, the guide tube, and the central tube bundle in turn, so that further polymerization reaction occurs. The separation section 441 is also provided with a separation tube 445 which is connected to a storage device 70 for storing solid colloid particles obtained by the reaction. The separation tube 445 coincides with the center line of the separation section 441, so that the solid polymer particles accumulated on the top of the separation section 441 can enter the storage device 70 along the separation tube 445 on the top of the separation section 441 for storage.

[0055] In some preferred technical solutions, the separation section 441 and the conveying section 442 are interconnected by a constriction section 443 with a gradually decreasing diameter. Furthermore, the constriction section 443 of the cyclone separation tube bundle 44 is composed of a plurality of mutually connected truncated cone tubes 446, and the cone angles of the truncated cone tubes 446 decrease in sequence from top to bottom. This structure makes the passage gradually narrower when the material flows through the constriction section 443, and the flow direction of the material changes more dramatically due to the change in the cone angle. In the cyclone separation process, this structure enhances the intensity of the cyclone. When the material enters the constriction section 443 after generating a cyclone in the separation section 441, the cyclone will be further enhanced as the passage shrinks and the flow direction changes, thereby generating a greater centrifugal force. For solid-liquid separation, a greater centrifugal force is conducive to more effectively throwing solid particles and solid polymers to the edge of the separation section. Under the action of the enhanced centrifugal force, they can gather faster to the tube wall of the separation section 441 and be better separated from the liquid medium. In addition, the structure with gradually decreasing cone angle can achieve more delicate separation of solid particles of different particle sizes. During the cyclone process, solid particles with larger particle sizes will first move toward the tube wall under the action of centrifugal force. As the channel further shrinks and the cyclone intensity increases, solid particles with smaller particle sizes will gradually be separated. This structure can perform layered separation according to particle size, avoiding incomplete separation due to differences in particle size. The connection structure of the truncated cone tube 446 makes the flow of materials more orderly. Compared with a simple suddenly contracted channel, this gradual structure can reduce flow disorder and turbulence. In cyclone separation, a stable flow state helps to maintain the stability of the cyclone, thereby ensuring the consistency of the separation effect.

[0056] In order to allow the solid colloid particles flowing out of the separation tube 445 of the cyclone separation tube bundle 44 to flow out smoothly from the slurry outlet 20 instead of being mixed with the slurry, in some preferred schemes of this embodiment, a slurry interlayer 31 is also provided on the top of the top cover for gathering the solid colloid particles flowing out of the separation tube at the upper end of the cyclone separation tube bundle, and the slurry interlayer is connected to the slurry outlet.

[0057] In addition, in the preferred solution of this embodiment, in order to make the slurry enter the cyclone separation tube bundle 44 more smoothly, the top cover 30 is also provided with an upper deflector 32 for guiding the slurry obtained by the reaction.

[0058] In some preferred embodiments, in order to make the turbine device 60 more effective in conveying and mixing materials, the turbine device 60 in the present application includes a nose cone 61 arranged at the center of the bottom cover for guiding the material to flow toward the guide tube, a turbine 62 arranged at the top of the nose cone, and a driving device 63 arranged under the bottom cover 50 for driving the turbine 62 to move.

[0059] Among them, the nose cone extends upward to the inside of the guide tube, and its main function is to guide the material to flow into the guide tube 41. The shape of the nose cone 61 can make the material discharged from the turbine device 60 converge more concentratedly to the guide tube 41, ensuring that the material enters the guide tube 41 in an orderly manner, thereby forming a stable circulation flow in the reaction tube. This guiding effect can avoid the disordered diffusion or local accumulation of materials in the bottom cover 50 area, so that the material can participate in the reaction process more efficiently. The turbine 62 is arranged at the top of the nose cone 61, and this position helps to enhance the efficiency of the turbine 62. The main function of the turbine 62 is to drive the mixing and flow of materials. When it is located at the top of the nose cone 61, it can better utilize the power generated by its rotation to push the material. The nose cone 61 can be used as a guide structure to make the material discharged from the turbine 62 flow in a specific direction, thereby increasing the flow rate and directionality of the material. Therefore, in this embodiment, the material is guided into the guide tube 41 by the nose cone 61, and combined with the power of the turbine 62, a relatively stable circulation flow pattern can be formed in the reaction tube 1, reducing the occurrence of turbulence and dead zones. Stable circulation flow can make the reaction materials fully contact in all areas, promote the uniform mixing of monomers and catalysts, and is conducive to the uniform progress of the polymerization reaction. It also helps the transfer and exchange of heat and has a positive effect on the control of reaction temperature.

[0060] Example 2 like Figure 5 As shown, Example 2 is a variation of Example 1, and the difference between Example 2 and Example 1 is that the location of the cyclone separation tube bundle 44 is changed, and it is transferred from the inside of the reaction tube 1 to the outside of the reaction tube 1. When the cyclone separation tube bundle 44 is arranged outside the reaction tube 1, maintenance and overhaul work will become more convenient, and the operator can more directly inspect, repair or replace parts without going deep into the reaction tube to perform complicated operations.

[0061] The cyclone separation tube bundles 44 are connected in parallel to form a cyclone separation tube group 45. During the production process, part of the cyclone separation tube bundles can be flexibly selected to be activated or deactivated according to the actual reaction conditions and separation requirements. Since the cyclone separation tube group 45 is also reacting inside, the cyclone separation tube group 45 must also be cooled. Therefore, in the preferred solution of this embodiment, a cooling jacket 46 is also provided outside the cyclone separation tube group 45, into which a cooling medium can be passed to remove the reaction heat inside the cyclone separation tube bundle.

[0062] Since the cyclone separation tube bundle 44 is arranged outside the reaction tube 1, the slurry interlayer 31 arranged in the original embodiment 1 is necessarily cancelled, and at the same time, the space inside the tube body 40 is completely occupied by the central tube bundle 42. The slurry inside the top cover 30 is directly connected to the cyclone separation tube bundle 44 in the cyclone separation tube group 45 through a pipeline, so as to separate the slurry. The separated unreacted monomers flow back to the bottom cover 50 again through the conveying pipeline. However, due to the extension of the overall material flow path, the flow pressure of the internal material is reduced. Therefore, in this embodiment, a booster pump 447 for conveying the reaction material is also arranged between the cyclone separation tube group 45 and the reaction tube 1, so as to meet the flow requirements of the material between different devices.

[0063] The examples of the present invention are merely illustrative of the technical solutions of the present invention. Any modifications, supplements or equivalent substitutions made by technicians in the field of the present invention on the basis of the examples are within the scope of protection required by the claims of the present invention.

Claims

1. A polymerization reactor, comprising a reaction tube, wherein the reaction tube is provided with a material inlet for introducing a reaction material and a slurry outlet for discharging the reaction material, the reaction tube comprises a top cover, a tube body and a bottom cover, the three of which are separated from each other by a partition, and the bottom cover is provided with a turbine device for driving material mixing and flow, characterized in that: A guide cylinder connected to the bottom cover is arranged at the center of the tube body, and a plurality of central tube bundles arranged in an array and connected to the top cover are extended upward from the top of the guide cylinder. A refrigeration jacket is formed between the inner wall of the tube body, the central tube bundle and the guide cylinder to pass a cooling medium to remove the reaction heat inside the central tube bundle; The polymerization reactor further comprises a plurality of cyclone separation tube bundles connected to the top cover and the bottom cover, so that a circulation passage for the reaction material to flow is formed between the bottom cover, the guide tube, the central tube bundle, the top cover and the cyclone separation tube bundle; The cyclone separation tube bundle comprises a separation section and a conveying section from top to bottom, the separation section and the conveying section are connected to each other via a contraction section with a gradually decreasing diameter, a material inlet pipe connected to the top cover is provided at the end of the separation section, the material inlet pipe is connected to the separation section along the tangent direction of the separation section, and a separation tube connected to a storage device for storing solid colloid particles obtained by the reaction is also provided on the separation section, and the center lines of the separation tube and the separation section coincide with each other.

2. A polymerization reactor according to claim 1, characterized in that: The contraction section of the cyclone separation tube bundle is composed of a plurality of mutually connected frustum tubes, and the cone angles of the frustum tubes decrease in sequence from top to bottom.

3. A polymerization reactor according to claim 1 or 2, characterized in that: The cyclone separation tube bundle is arranged inside the tube body of the reaction tube and arranged in an array on the outer circumference.

4. A polymerization reactor according to claim 3, characterized in that: The top of the top cover is provided with a slurry interlayer for gathering solid colloid particles flowing out of the separation tube at the upper end of the cyclone separation tube bundle, and the slurry interlayer is connected with the slurry outlet.

5. A polymerization reactor according to claim 1 or 2, characterized in that: The cyclone separation tube bundle is arranged outside the reaction tube and is arranged in parallel with each other to form a cyclone separation tube group.

6. A polymerization reactor according to claim 5, characterized in that: The outer part of the cyclone separation tube group is sleeved inside a cooling jacket into which a cooling medium can be passed to remove the reaction heat inside the cyclone separation tube bundle.

7. A polymerization reactor according to claim 5, characterized in that: A booster pump for conveying reaction materials is also arranged between the cyclone separation tube group and the reaction tube.

8. A polymerization reactor according to claim 1, characterized in that: The turbine device includes a nose cone arranged at the center of the bottom cover for guiding the material to flow toward the guide tube, the nose cone extends upward to the inside of the guide tube, and the turbine device also includes a turbine arranged at the top of the nose cone.

9. A polymerization reactor according to claim 1 or 8, characterized in that: A lower flow guide for enhancing the mixing effect of the reaction materials is also arranged on the inner wall of the flow guide cylinder, and the lower flow guide extends downward to the inner space of the bottom cover.

10. A polymerization reactor according to claim 1, characterized in that: The material inlet includes a catalyst inlet and a polymerization feed inlet arranged at the bottom cover; The bottom cover is also provided with a driving device for driving the turbine device to move; The tube body is provided with a coolant inlet and a coolant outlet for the cooling medium to enter and flow out; The top cover is also provided with an upper deflector for guiding the slurry obtained by the reaction.

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