Dynamic mixer and application thereof

Abstract

The invention provides a dynamic mixer and application thereof. The dynamic mixer comprises a shell, a stirring paddle, a motor, a feeding hole and a discharging hole, a plurality of annular baffles are arranged on the inner wall of the shell; the stirring paddle is arranged in the shell, the stirring paddle is provided with a plurality of paddle blades, and the paddle blades and the annular baffles are alternately arranged; the motor is arranged at the top of the shell and drives the stirring paddle to rotate; wherein the rotating speed of the stirring paddle is 1,500 rpm to 2,500 rpm. Through the application of the dynamic mixer, the mixing effect of water / glue is remarkably improved, the size of oil-phase liquid beads is reduced, the dispersity of the oil-phase liquid beads in water is improved, refining and homogenization of the size of the glue particles are facilitated, the phenomenon of glue hanging during concentration of the glue particle water is avoided, and conveying of the glue particle water is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical equipment, in particular to a dynamic mixer and application thereof. Background Art

[0002] Styrene butadiene rubber is one of the earliest synthetic rubber varieties to achieve industrial production and has the largest production capacity. It is a random copolymer of styrene and butadiene and is widely used in vulcanized rubber products such as tires, plastic modification, and shoe materials. Styrene butadiene rubber has excellent heat resistance, wear resistance, and aging resistance. Its processing performance and product performance are close to those of natural rubber, and its vulcanization performance is better than that of natural rubber. Its main production processes are emulsion polymerization and solution polymerization.

[0003] Emulsion polymerization adopts a free radical polymerization mechanism, but it has disadvantages such as wide molecular weight distribution and uncontrollable structure. In addition, more additives are added during the emulsion polymerization process, and the emulsifier residue in the product is high, resulting in certain quality defects, and the production process produces more sewage, which is easy to pollute the environment. In contrast, solution polymerization uses alkyl lithium to initiate the random copolymerization of butadiene and styrene, which can accurately control the monomer ratio, sequence distribution, microstructure and molecular weight, with a narrow molecular weight distribution, high product purity, excellent performance, and no pollution in the production process, with little impact on the environment. The technical innovation of the present invention is mainly focused on the optimization of the coagulation process of solution-polymerized styrene-butadiene rubber.

[0004] As greenhouse gas emissions increase, climate change becomes increasingly serious, and countries around the world are stepping up efforts to promote environmental protection measures and carbon emission regulations. These measures not only help mitigate global warming and protect the ecological environment, but also save energy and reduce costs by optimizing production processes and improving energy efficiency, and respond to market demand for green products. Implementing carbon reduction measures not only helps companies achieve economic benefits, but also contributes to sustainable development.

[0005] The prior art proposes a carbon reduction technology solution for the stripping unit of solution polystyrene butadiene rubber. During the stripping process, a large amount of high-temperature steam needs to be sprayed into the coagulation kettle to separate volatile components (such as cyclohexane and n-hexane solvents) from the rubber solution. This process consumes a lot of heat energy, and because the dilution degree of the rubber water is large and the water content is high, the coagulation kettle needs to consume more steam to ensure the effective separation of the solvent. In order to reduce steam energy consumption and achieve carbon reduction, the concentration of the rubber water must be increased. However, increasing the concentration may cause the size of the rubber particles to increase and become uneven, and too much oil is locked inside the large rubber particles, which is not conducive to solvent separation and is also prone to causing problems such as rubber hanging, kettle lumps, and even pipeline blockage in the coagulation kettle. Summary of the invention

[0006] The present invention proposes a scheme of installing a dynamic mixer in the coagulation and stripping unit of solution-polymerized styrene-butadiene rubber to improve the mixing effect of the water phase and the rubber particles, so that the size of the oil phase liquid droplets is smaller and the dispersion effect in water is better. This measure can effectively refine and homogenize the size of the rubber particles, thereby ensuring that even when the concentration of the rubber particle water is increased, the rubber particle water can be transported more smoothly, and the continuous operation of the post-processing unit can be ensured. Through this technology, not only can steam consumption be reduced and carbon reduction goals be achieved, but also production capacity can be increased.

[0007] To achieve the above-mentioned purpose, the present invention provides a dynamic mixer, which includes a shell, a stirring paddle, a motor, a feed port and a discharge port; the shell, the inner wall of the shell is provided with a plurality of annular baffles; the stirring paddle is arranged inside the shell, the stirring paddle is provided with a plurality of blades, and the blades and the annular baffles are arranged alternately; the motor is arranged at the top of the shell and drives the stirring paddle to rotate; wherein the rotation speed of the stirring paddle is 1500rpm-2500rpm.

[0008] Furthermore, the shell includes a cylinder, an upper head and a lower head, the cylinder is a hollow cylindrical structure, the upper head is an arc structure, and the lower head is a conical structure.

[0009] Furthermore, the height-to-diameter ratio of the cylinder is 2.0 / 1-20.0 / 1; and / or the taper of the lower head is 1.0-12.0.

[0010] Furthermore, the number of layers of the annular baffles is 4-6; and / or the annular baffles are evenly distributed longitudinally along the inner wall of the shell; and / or the plane of the annular baffles is perpendicular to the inner wall of the shell; and / or the hollow inner diameter of the annular baffles is 1 / 4-1 / 2 of the inner diameter of the shell.

[0011] Furthermore, the stirring impeller includes at least one of a paddle-type stirring impeller, a propeller-type stirring impeller, an open-type turbine impeller or a disc-type turbine impeller.

[0012] Furthermore, the spacing between the outer edge of the blade close to the inner wall of the shell and the inner wall of the shell is a first spacing, and the ratio of the first spacing to the inner diameter of the shell is less than 5%; and / or the blade tip linear velocity of the blade is greater than 10m / s.

[0013] Furthermore, the cavity volume of the shell is φ450m×650m.

[0014] Furthermore, the feed port is arranged at the bottom of the shell, and the discharge port is arranged at the top of the shell.

[0015] The present invention also provides an application of the dynamic mixer as described above, wherein the dynamic mixer is applied to a coagulation unit of a solution-polymerized styrene-butadiene rubber production device to disperse and refine the rubber particle water.

[0016] Furthermore, the dynamic mixer is arranged on the water gel feed pipeline of the coagulation kettle.

[0017] After adopting the technical solution of the present invention, the following technical effects can be achieved: (1) Improve the mixing effect and promote the refinement of colloid particles: Through the use of dynamic mixers, the water / colloid mixing effect is significantly improved, the size of oil phase liquid droplets is reduced, and its dispersibility in water is improved, which helps to refine and homogenize the size of colloid particles, ensure that there is no glue hanging when the colloid water is concentrated, and facilitate the transportation of colloid water; (2) Ensure the colloid water transport capacity and reduce energy consumption: The mixer adopts a high-power, high-speed motor and a precise blade design to effectively break up the oil phase droplets and improve the oil-water dispersion efficiency. While the colloid water is concentrated, the colloid water transport capacity is ensured while reducing steam consumption, achieving carbon reduction and energy efficiency improvement; (3) Enhance the uniformity of water-gel mixing and improve production capacity: The multi-layer annular baffle design forces the water-gel mixture flowing along the inner wall of the shell to change its flow direction from longitudinal to transverse, promoting uniform dispersion and mixing of the water-gel, enhancing the mixing effect, and further improving the continuous operation capacity and production capacity of the post-processing unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 A schematic diagram of the structure of a dynamic mixer provided by an embodiment of the present invention; Figure 2 A schematic structural diagram of a dynamic mixer provided in an embodiment of the present invention.

[0019] Description of reference numerals: 10-shell; 11-annular baffle; 12-cylinder; 13-upper head; 14-lower head; 20-stirring paddle; 21-paddle; 30-motor; 40-feed port; 50-discharge port. DETAILED DESCRIPTION

[0020] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] An embodiment of the present invention provides a dynamic mixer, which includes a shell 10, a stirring paddle 20, a motor 30, a feed port 40 and a discharge port 50; the shell 10, the inner wall of the shell 10 is provided with a plurality of annular baffles 11; the stirring paddle 20, the stirring paddle 20 is arranged inside the shell 10, the stirring paddle 20 is provided with a plurality of blades 21, and the blades 21 and the annular baffles 11 are arranged alternately; the motor 30, the motor 30 is arranged at the top of the shell 10, and drives the stirring paddle 20 to rotate; wherein, the rotation speed of the stirring paddle 20 is 1500rpm-2500rpm.

[0022] like Figure 1 and Figure 2 As shown, the present invention relates to a dynamic mixer, in which the annular baffle 11 on the inner wall of the shell 10 plays a role in limiting and guiding the flow of fluid, thereby enhancing the uniformity of the material during the mixing process. This design can prevent the material from being separated into layers or insufficiently stirred due to uneven mixing. The blades 21 of the stirring paddle 20 are alternately arranged with the annular baffle 11, which can effectively change the flow direction of the fluid and prevent the material from flowing along a single path, thereby further improving the mixing efficiency. The dynamic mixer adopts a high-power motor 30, the power of the motor 30 is 30kW, and the speed can be as high as 2000rpm. The high-speed motor 30 helps to break up the oil phase droplets, making the droplets smaller in size, thereby promoting the uniform dispersion of the oil phase in water, and ultimately helping to refine and homogenize the oil phase droplets.

[0023] The design of the annular baffle 11 and the alternately arranged blades 21 can increase the flow path and contact surface of the material, reduce dead angles and unevenness, and improve the mixing effect of the material. The higher the speed of the stirring paddle 20 and the power setting of the motor 30, the dynamic mixer of this embodiment has a better mixing effect than the traditional mixer. The structural design of the housing 10 and the stirring paddle 20 takes into account the stability of long-term use, which can reduce failures caused by frequent operation and extend the service life of the equipment.

[0024] In some embodiments of the present application, the shell 10 includes a cylinder 12, an upper head 13 and a lower head 14, the cylinder 12 is a hollow cylindrical structure, the upper head 13 is an arc structure, and the lower head 14 is a conical structure.

[0025] like Figure 2 As shown, the structure of the shell 10 consists of three parts: a cylinder 12, an upper head 13 and a lower head 14. Among them, the cylinder 12 is a hollow cylindrical structure with certain strength and stability. The upper head 13 adopts an arc-shaped structure and is located at the upper end of the shell 10. Its arc-shaped design can enhance the strength and pressure resistance of the shell 10, and can also avoid material accumulation at the top of the cavity. The lower head 14 is located at the lower end of the shell 10. Its conical shape helps the smoothness of fluid flow, reduces retention and uneven flow, and makes it more efficient during the processing of the internal cavity.

[0026] In some embodiments of the present application, the height-to-diameter ratio of the cylinder 12 is 2.0 / 1-20.0 / 1; and / or the taper of the lower head 14 is 1.0-12.0.

[0027] By adjusting the height-to-diameter ratio of the cylinder 12 and the taper of the lower head 14, the flow pattern of the fluid inside the shell 10 can be accurately controlled to optimize the mixing process. Especially in dynamic mixers, these designs can effectively improve the mixing efficiency, promote the uniform dispersion of the oil-water phase, reduce the particle size, and make the final product more uniform. A reasonable height-to-diameter ratio can enhance the mechanical strength of the shell 10 and ensure that it is not easily deformed under high pressure or high load. At the same time, the optimization of the taper can also enable the lower head 14 to withstand more pressure without cracking or deformation, thereby improving the reliability and durability of the overall structure.

[0028] The cavity of the dynamic mixer is designed to be conical at the bottom, cylindrical in the middle, and arc-shaped at the top. The taper of the bottom ranges from 1.0 to 12.0, and the height-to-diameter ratio of the cylindrical part can be adjusted between 2.0 / 1 and 20.0 / 1. This design helps promote the longitudinal mixing of materials.

[0029] In some embodiments of the present application, the number of layers of the annular baffle 11 is 4-6; and / or the annular baffle 11 is evenly distributed longitudinally along the inner wall of the shell 10; and / or the plane where the annular baffle 11 is located is perpendicular to the inner wall of the shell 10; and / or the hollow inner diameter of the annular baffle 11 is 1 / 4-1 / 2 of the inner diameter of the shell 10.

[0030] like Figure 2 As shown, the resistance and disturbance of fluid flow are increased by setting up multiple layers of baffles, thereby optimizing the mixing and mass transfer effects of the fluid; the multiple layers of annular baffles 11 can increase the residence time of the fluid in the shell 10, and promote more thorough mixing of the fluid. The uniform longitudinal distribution of the annular baffles 11 along the inner wall of the shell 10 helps the fluid to flow evenly throughout the cylinder 12, avoids excessively high or low local flow rates, and ensures that each part of the fluid can fully contact with other components, thereby achieving a more uniform mixing effect. By designing the plane of the baffle to be perpendicular to the inner wall of the shell 10, the flow direction of the fluid can be effectively changed, forcing the fluid to bypass each layer of the baffle. This design helps to enhance the disturbance of the fluid, make the mixing effect more uniform, and prevent radial flow of the fluid and the formation of dead zones. The range setting of the hollow inner diameter of the annular baffle 11 helps the fluid to be constrained to a certain extent when passing through these hollow areas, avoiding uneven flow of the fluid due to excessively large or small diameters.

[0031] The six layers of annular baffles 11 of the dynamic mixer are evenly distributed longitudinally along the inner wall of the cavity, the inner diameter of the annular baffles 11 is between 1 / 4 and 1 / 2 of the inner diameter of the cavity, and its plane is perpendicular to the inner wall of the cavity. This design can make the water / glue mixture between the outer edge of the blade 21 and the inner wall of the cavity change from longitudinal flow to lateral flow, thereby promoting more uniform dispersion and mixing of water and glue.

[0032] It should also be noted that the number of layers of blades 21 in the dynamic mixer is one more than the number of layers of the annular baffle 11, so that each layer of blades 21 is located in the baffle compartment, ensuring that each layer of blades 21 can fully stir the fluid during the mixing process. This design optimizes the mixing path of the fluid, so that the fluid can be effectively disturbed and stirred between each layer, thereby improving the overall mixing effect.

[0033] In some embodiments of the present application, the stirring impeller 20 includes at least one of a paddle-type stirring impeller, a propeller-type stirring impeller, an open-type turbine impeller, or a disc-type turbine impeller.

[0034] The design of the stirring paddle 20 in the dynamic mixer can be various. By combining different types of stirring paddles 20, such as paddle type, propeller type, open turbine paddle and disc turbine paddle, the stirring effect can be optimized according to the properties of the fluid, the mixing requirements and the characteristics of the production process. For example, the use of an open turbine paddle can enhance the shearing effect of the fluid, thereby better completing high shear tasks such as dispersion and emulsification; while the use of a paddle type stirring paddle can effectively promote the flow of the fluid, which is suitable for low shear and efficient mixing.

[0035] Different types of impellers 20 can be flexibly selected and adjusted according to the viscosity, particle size, flow characteristics, etc. of the mixture, so as to ensure that the mixer has a wide range of applications and can meet different material and process requirements. For example, a push-type impeller can be used for large-scale production, while an open turbine impeller can meet the dispersion requirements of fine particles.

[0036] Reasonable selection and combination of different types of impellers 20 can improve the mixing efficiency and reduce energy consumption while ensuring the mixing effect. For example, the paddle impeller 20 can push large-scale fluids under low shear conditions, reducing the power demand during operation; while the disc-type turbine impeller is suitable for high shear and rapid mixing, reducing the energy waste caused by long-term mixing.

[0037] The dynamic mixer can adopt various blade 21 designs according to needs, such as three-blade, four-blade, six-blade paddle stirring paddles; three-blade, four-blade, six-blade propulsion stirring paddles; straight-blade, curved-blade, folding-blade open-type turbine paddles; straight-blade, curved-blade, folding-blade disc-type turbine paddles.

[0038] In some embodiments of the present application, the spacing between the outer edge of the blade 21 close to the inner wall of the shell 10 and the inner wall of the shell 10 is a first spacing, and the ratio of the first spacing to the inner diameter of the shell 10 is less than 5%; and / or the blade tip linear velocity of the blade 21 is greater than 10 m / s.

[0039] The first spacing refers to the distance between the outer edge of the blade 21 and the inner wall of the housing 10, which is set to be less than 5% of the inner diameter of the housing 10, so as to ensure that the distance between the blade 21 and the inner wall of the housing 10 is small enough, thereby enhancing the stirring effect of the blade 21 and improving the disturbance degree of the fluid. The smaller spacing enables the blade 21 to better control the flow of the fluid, avoid the formation of a dead zone between the fluid and the cavity wall, and promote more effective material mixing and fluid shearing.

[0040] The blade tip linear velocity refers to the movement speed of the edge of the blade 21. When set to be greater than 10 m / s, it can provide strong shear force and fluid disturbance, and enhance the dispersion and emulsification effect of the material. A higher blade tip linear velocity can effectively break up the oil phase droplets and decompose large droplets into smaller droplets, thereby improving the uniformity of the oil-water mixture, especially when dealing with emulsified or dispersed oil phases, which can significantly improve the mixing efficiency.

[0041] In some embodiments of the present application, the cavity volume of the shell 10 is φ450m×650m.

[0042] The cavity volume refers to the spatial capacity inside the mixer, that is, the volume of fluid that the mixer housing 10 can accommodate. The volume is φ450mm×650mm, which means that the diameter of the cavity is 450mm and the length is 650mm. This design provides a specific processing capacity for the dynamic mixer, which can accommodate a certain volume of material for mixing, dispersion and emulsification operations. By properly selecting the size of the cavity, the mixing effect can be optimized, ensuring that the agitator 20 can effectively interact with the fluid, avoiding uneven material flow due to too small a cavity volume or energy waste due to too large a volume.

[0043] In some embodiments of the present application, the feed port 40 is disposed at the bottom of the shell 10 , and the discharge port 50 is disposed at the top of the shell 10 .

[0044] like Figure 1As shown, the design of the feed port 40 being arranged at the bottom and the discharge port 50 being arranged at the top facilitates the natural flow of materials in the mixer. This layout utilizes the principle of fluid mechanics and can promote the upward flow of materials in the mixer to avoid stagnation or retention of materials. When the feed port 40 is located at the bottom, the material is introduced into the bottom layer of the mixer and discharged through the top discharge port 50 after stirring, so that the fluid can flow more smoothly during the mixing process and avoid the retention of fluid in certain areas. During the rising process, the material passes through the action of the stirring paddle 20 blades, thereby fully realizing the operations of mixing, dispersing, and emulsifying, and improving the overall mixing efficiency and dispersion effect. This design can ensure that the contact time and contact area of ​​the material inside the mixer are maximized, thereby achieving better processing effects.

[0045] An embodiment of the present invention further provides an application of the dynamic mixer as described above, wherein the dynamic mixer is applied to a coagulation unit of a solution-polymerized styrene-butadiene rubber production device to disperse and refine the rubber particle water.

[0046] The present embodiment provides an application of a dynamic mixer, in particular, the dynamic mixer is applied to the coagulation unit of a solution-polymerized styrene-butadiene rubber production device, for dispersing and refining the colloid water. The dynamic mixer is used here to process the colloid water, that is, the aqueous phase material containing colloids produced during the solution polymerization process. Solution-polymerized styrene-butadiene rubber is a rubber obtained by solvent polymerization, wherein the polymerization process of styrene-butadiene rubber occurs in a solvent. During the production process, the coagulation unit is used to coagulate and separate the polymerization product (colloid) from the solution. The colloid water is a mixture of the colloids, solvents, and dispersion media after coagulation during the production process. The goal of this unit is to process and optimize the properties of the colloid water.

[0047] Dispersion and refinement refers to further dispersing the solid particles in the colloid water through a dynamic mixer, reducing the size of the particles and keeping them evenly distributed in the water phase. By dispersing and refinement of the colloid water, the aggregation and precipitation of the particles are avoided and the dispersion stability of the particles is improved, which is crucial for subsequent production steps (such as dehydration, drying or reprocessing of the rubber).

[0048] In some embodiments of the present application, the dynamic mixer is provided on the water gel feed line of the coagulation kettle.

[0049] The dynamic mixer can dynamically mix different materials, especially when processing materials with high viscosity or uneven particle size. In this embodiment, the dynamic mixer is installed on the water-gel feed pipeline of the bottom side line of the coagulation kettle, and is installed vertically with the agitator installed downwards. It is mainly used to fully mix and refine the gel water entering the coagulation kettle, so that the gel is dispersed more evenly in the water phase.

[0050] The coagulation reactor is an important equipment in the production process of solution polystyrene butadiene rubber. It is used to separate rubber particles from the solution, remove solvents, and coagulate rubber. In the production process, the water-gel feed pipeline is used to feed the aqueous phase material containing rubber particles into the coagulation reactor. The properties of the rubber water will directly affect the efficiency of the coagulation process and the quality of the final rubber product. The design of arranging the dynamic mixer in the water-gel feed pipeline aims to refine and disperse the rubber particles through the dynamic mixer before the rubber water enters the coagulation reactor to ensure the uniformity of the rubber water. This configuration can effectively avoid the phenomenon of aggregation, precipitation or uneven distribution of rubber particles, ensuring that they can smoothly enter the coagulation reactor for subsequent treatment.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dynamic mixer, characterized in that: The dynamic mixer comprises: A housing (10), wherein the inner wall of the housing (10) is provided with a plurality of annular baffles (11); A stirring paddle (20), the stirring paddle (20) being arranged inside the housing (10), the stirring paddle (20) being provided with a plurality of blades (21), the blades (21) and the annular baffle (11) being arranged alternately; a motor (30), the motor (30) being disposed on the top of the housing (10) and driving the stirring paddle (20) to rotate; Wherein, the rotation speed of the stirring paddle (20) is 1500 rpm-2500 rpm.

2. The dynamic mixer according to claim 1, characterized in that The shell (10) comprises a cylinder (12), an upper head (13) and a lower head (14); the cylinder (12) is a hollow cylindrical structure, the upper head (13) is an arc-shaped structure, and the lower head (14) is a conical structure.

3. The dynamic mixer according to claim 2, characterized in that The height-to-diameter ratio of the cylinder (12) is 2.0 / 1-20.0 / 1; and / or The taper of the lower head (14) is 1.0-12.

0.

4. The dynamic mixer according to claim 1, characterized in that The number of layers of the annular baffles (11) is 4 to 6; and / or The annular baffles (11) are evenly distributed longitudinally along the inner wall of the housing (10); and / or The plane on which the annular baffle (11) is located is perpendicular to the inner wall of the housing (10); and / or The hollow inner diameter of the annular baffle (11) is 1 / 4 to 1 / 2 of the inner diameter of the shell (10).

5. The dynamic mixer according to claim 1, characterized in that The stirring impeller (20) comprises at least one of a paddle-type stirring impeller, a propeller-type stirring impeller, an open-type turbine impeller or a disc-type turbine impeller.

6. The dynamic mixer according to claim 1, characterized in that The distance between the outer edge of the blade (21) close to the inner wall of the shell (10) and the inner wall of the shell (10) is a first distance, and the ratio of the first distance to the inner diameter of the shell (10) is less than 5%; and / or The blade tip linear speed of the blade (21) is greater than 10 m / s.

7. The dynamic mixer according to claim 1, characterized in that The cavity volume of the shell (10) is φ450m×650m.

8. The dynamic mixer according to claim 1, characterized in that The dynamic mixer further comprises a feed port (40) and a discharge port (50), wherein the feed port (40) is arranged at the bottom of the shell (10), and the discharge port (50) is arranged at the top of the shell (10).

9. Use of a dynamic mixer as claimed in any one of claims 1 to 8, characterized in that: The dynamic mixer is applied to a coagulation unit of a solution-polymerized styrene-butadiene rubber production device to disperse and refine the rubber particle water.

10. The use according to claim 9, characterized in that: The dynamic mixer is arranged on the water gel feed pipeline of the coagulation kettle.

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