Wet crushing and swelling equipment for pulp and preparation system of fiber spinning solution

Abstract

The utility model relates to wet crushing swelling equipment for pulp and a preparation system of fiber spinning dope, which comprises a reaction tank, a motor and a stirring mechanism, the stirring mechanism comprises a stirring shaft, a guide cylinder, a moving cutter component and a static cutter component, and the stirring shaft is in transmission connection with the motor; the static cutter assembly comprises a center block and a plurality of static cutter parts, the center block sleeves the outer side of the stirring shaft, and the two ends of each static cutter part are connected to the center block and the guide cylinder respectively; the movable cutter assembly comprises a mounting block and a plurality of movable cutter parts connected to the mounting block; the moving cutter assembly is used for rotating relative to the static cutter assembly under the driving of the stirring shaft, so that the moving cutter assembly and the adjacent static cutter assembly form shearing fit in the guide cylinder; the equipment can synchronously realize wet crushing and swelling of pulp, has the advantages of lower cost, higher efficiency and the like, not only can eliminate potential safety hazards existing in the pulp crushing process, but also can promote cellulose to be more uniformly dispersed in a solvent, and achieves the effect of more sufficient and more uniform swelling.

Description

Technical Field

[0001] The utility model relates to the technical field of novel cellulose fiber production, in particular to a wet crushing and swelling device for pulp and a preparation system for fiber spinning solution. Background Art

[0002] Lyocell is a new green fiber produced through a physical dissolution-regeneration process using an aqueous solution of NMMO as a solvent. Compared to viscose, Lyocell boasts a greener and more environmentally friendly production process, higher fiber strength, and better dyeing properties. In recent years, an increasing number of viscose fiber manufacturers have been transitioning to Lyocell, leading to increasingly fierce market competition.

[0003] In the industrial production process, lyocell fiber spinning solution is prepared by mixing pulp raw material with solvent to prepare cellulose suspension. After the cellulose in the suspension is fully swollen, it enters a dissolving device (e.g., a thin film evaporator) for dissolution to obtain spinning solution. At present, the industrial preparation of lyocell fiber spinning solution is mainly divided into two routes: wet process and dry process. The wet process route is to first mix pulp and water to a certain concentration, squeeze to obtain a material with a certain dryness, then crush it, and then add a solvent (such as NMMO aqueous solution) for premixing, and finally enter a reactor to prepare the spinning solution; the dry process route is to first crush the pulp, then add a solvent (such as NMMO aqueous solution) for premixing, and finally enter a reactor to prepare the spinning solution. Whether it is a dry process or a wet process, the crushed pulp raw material needs to be pre-mixed with a solvent to swell the cellulose through pre-mixing. In practice, corresponding crushing equipment and pre-mixing equipment need to be configured. On the one hand, the cost is higher, and the pulp raw material needs to go through the crushing process and the pre-mixing process in succession, which takes a longer process and leads to lower efficiency. On the other hand, during the crushing of dry pulp in the existing crushing equipment, dust is easily generated, which poses a safety hazard. In addition, the process of pre-mixing the pulp raw material and the solvent in the pre-mixing equipment also has the problems of insufficient contact and uneven swelling, which need to be solved urgently. Summary of the Invention

[0004] The first aspect of the present invention aims to solve the above-mentioned technical problems and provides a wet crushing and swelling device suitable for the industrial preparation of lyocell fiber spinning solution. The device can simultaneously realize wet crushing and swelling of pulp, has the advantages of lower cost and higher efficiency, and can not only eliminate the hidden danger of dust generated during the pulp crushing process, but also improve the swelling efficiency and uniformity. The main concepts are:

[0005] A wet crushing and swelling device for pulp comprises a reaction tank, a motor and a stirring mechanism, wherein a reaction chamber is constructed in the reaction tank, the stirring mechanism comprises a stirring shaft, a guide tube, a moving knife assembly arranged in the guide tube and a stationary knife assembly arranged in the guide tube, wherein the guide tube is arranged in the reaction chamber through a bracket; the stirring shaft is arranged vertically, the upper end of the stirring shaft is connected to the motor transmission, the lower end of the stirring shaft extends into the reaction chamber, and the lower end of the stirring shaft is at least inserted into the guide tube; the stationary knife assembly comprises a central block and a plurality of stationary knife components, the central block is sleeved on the outer surface of the stirring shaft On the other side, one end of the stationary knife component is connected to the central block, and the other end is connected to the guide tube, and the stationary knife components are evenly distributed along the circumferential direction of the stirring shaft; the moving knife assembly is constructed to adapt to the stationary knife assembly and is located at the position adapted to the stationary knife assembly, the moving knife assembly includes a mounting block for connecting the stirring shaft and a plurality of moving knife components connected to the mounting block, and the moving knife components are evenly distributed along the circumferential direction of the stirring shaft; the moving knife assembly is used to rotate relative to the stationary knife assembly under the drive of the stirring shaft, so that the moving knife assembly and the adjacent stationary knife assembly form a shear fit in the guide tube. In this solution, by arranging a stationary blade assembly and a movable blade assembly within a guide tube, the movable blade assembly and the adjacent stationary blade assembly form a shearing engagement zone within the guide tube. Simultaneously, the guide tube and the movable blade assembly cooperate to guide the liquid within the reaction tank to circulate, with the circulating liquid continuously passing through the shearing engagement zone. This not only simultaneously achieves wet pulverization and swelling of the pulp, eliminating the potential risk of dust generation during the pulp pulverization process, but also promotes full pulp pulverization and more uniform dispersion of cellulose in the solvent, thereby achieving a more complete and uniform swelling effect. Compared to existing technologies, this wet pulverization and swelling equipment is an integrated device that can simultaneously achieve wet pulverization of the pulp feedstock and swelling of the cellulose in the pulp feedstock, eliminating the potential risk of dust generation during the pulp pulverization process and improving swelling efficiency and uniformity. In practical applications, this wet pulverization and swelling equipment can replace existing pulverization and premixing equipment, achieving not only lower costs, but also a shorter process flow and higher efficiency.

[0006] To prevent jamming, the stationary blade assembly is positioned in the middle and / or lower portion of the guide tube, and the movable blade assembly is also positioned in the middle and / or lower portion of the guide tube. In these locations, the pulp is fully exposed to the solvent and swells, significantly reducing its toughness. This not only makes it easier to crush the pulp, but also reduces the risk of jamming during the shearing process between the movable and stationary blade assemblies.

[0007] Furthermore, at least the upper end of the stationary blade component is constructed with a sawtooth structure, and the sawtooth structure is arranged along the length direction of the stationary blade component, so as to utilize the sawtooth structure to more efficiently crush the pulp.

[0008] Furthermore, a sawtooth structure is constructed along the length direction of the movable blade component so as to utilize the sawtooth structure to more efficiently crush the pulp.

[0009] To further improve swelling uniformity, the movable blade assembly is tilted relative to the horizontal to provide downward thrust. Because the movable blade assembly is in a rotating state, it can provide downward thrust to the liquid in the guide tube during rotation, pushing the liquid in the guide tube to flow from top to bottom. This can not only prevent blockage within the guide tube, but also drive the liquid to circulate along the height of the guide tube, which is more conducive to uniform swelling.

[0010] Furthermore, the stirring mechanism is configured with multiple moving blade assemblies and multiple stationary blade assemblies, which are staggered along the height of the guide tube. This allows each stationary blade assembly to form a shearing coordination with two adjacent moving blade assemblies, achieving not only better shearing effect and higher efficiency but also further dispersing the cellulose, thereby improving swelling uniformity.

[0011] Furthermore, the stirring mechanism also includes an impeller, which is mounted on the stirring shaft and located below the guide tube. The impeller rotates synchronously with the stirring shaft. In this embodiment, by disposing the impeller below the guide tube, the liquid in the guide tube, which flows downward from the top, is forced to flow upward between the guide tube and the tank body. The impeller can assist the downward flow of the liquid in the guide tube, further facilitating the formation of a circulation flow inside and outside the barrel, thereby further promoting the full comminution and uniform swelling of the pulp.

[0012] Furthermore, the reaction tank is also constructed with a feeding port for adding pulp raw materials, a solvent inlet for adding solvent, an assembly port and a discharge port. The feeding port, solvent inlet, assembly port and discharge port are respectively connected to the reaction chamber, and the stirring shaft extends into the reaction chamber through the assembly port.

[0013] In order to solve the problem of easy manufacturing and assembly, the reaction tank further includes a tank body, a tank cover and a frame, the reaction chamber is constructed on the tank body, the tank cover is detachably installed on the tank body and closes the reaction chamber, the feeding port, solvent inlet and assembly port are respectively constructed on the tank cover, and the discharge port is constructed on the tank body.

[0014] Preferably, the guide tube is constructed as a cylindrical structure, which is more conducive to guiding the circulation of liquid.

[0015] Furthermore, the outer side of the reaction tank is also provided with a heat-insulating structure.

[0016] The second aspect of the present invention aims to solve the problem that during actual operation, the load of the motor increases significantly, and the movable blade assembly and the static blade assembly are very likely to get stuck, resulting in the system being unable to operate stably. Furthermore, the stirring mechanism also includes a first crushing assembly, which is installed on the stirring shaft. The first crushing assembly is located in the guide tube and above the movable blade assembly. The first crushing assembly is arranged at a position corresponding to the middle or upper part of the guide tube. The pulp entering the guide tube can be crushed by the first crushing assembly alone. On the one hand, the pulp can be crushed into smaller pieces by the first crushing assembly, which is more convenient for the pulp to contact with the solvent more quickly and be soaked and swelled. On the other hand, it can slow down the pulp falling from the guide tube, increase the time for the pulp to fall into the matching shear zone below, which is more conducive to the pulp fully contacting with the solvent and swelling, so that the toughness of the pulp falling into the matching shear zone is greatly reduced, making it easier to be crushed, and effectively avoiding the problem of getting stuck.

[0017] Preferably, the first crushing assembly includes a mounting block for connecting to the stirring shaft and a plurality of first blades connected to the mounting block, and the first blades are evenly distributed along the circumferential direction of the stirring shaft; the first blades are arranged obliquely to the horizontal direction to provide downward thrust.

[0018] Preferably, the first blade is also constructed with a serration structure distributed along its length.

[0019] The third aspect of the present invention aims to solve the problem that during actual operation, the pulp put into the reaction tank is easily hung on the bracket of the guide tube and is not easy to enter the guide tube, which seriously affects the crushing and swelling process. Furthermore, the stirring mechanism also includes a second crushing assembly, which is installed on the stirring shaft and is located above the guide tube. The second crushing assembly rotates synchronously with the stirring shaft, and the rotation range of the second crushing assembly covers the feeding port;

[0020] The second crushing assembly includes a mounting block for connecting to the agitator shaft and multiple second paddles connected to the mounting block. The second paddles are evenly distributed along the circumference of the agitator shaft. This design, on the one hand, allows the second crushing assembly to crush pulp that has not been exposed to the solvent during feeding, allowing the pulp to more quickly and thoroughly come into contact with the solvent and swell. On the other hand, it also ensures that the pulp enters the guide tube as much as possible during feeding, greatly reducing the possibility of pulp falling between the guide tube and the tank body, making the crushing and swelling process smoother and more efficient.

[0021] Furthermore, the second blade is also constructed with a serration structure distributed along its length.

[0022] A system for preparing fiber spinning solution includes an extrusion device, a crushing and grinding device, a dissolving device and the wet crushing and swelling device, wherein the wet crushing and swelling device is connected to the extrusion device, the extrusion device is connected to the crushing and grinding device, and the crushing and grinding device is connected to the dissolving device.

[0023] Furthermore, the invention also includes a screw conveyor, the crushing and grinding equipment is connected to the screw conveyor, and the screw conveyor is connected to the dissolving device through a pipeline, so that the crushed and ground materials can be transported to the dissolving device by the screw conveyor.

[0024] To improve solvent utilization, the system further includes a solvent recovery tank, a delivery pump, and a filter. The extrusion device is configured with a reflux port for discharging the solvent, the reflux port being connected to the solvent recovery tank, which is in communication with the filter via the delivery pump, and the filter being in communication with the feed port via a pipeline. The solvent recovery tank is used to store recovered solvent, the delivery pump is used to provide delivery power, and the filter is used to filter the recovered solvent, removing residual pulp impurities to obtain a relatively pure solvent. The solvent can then be re-delivered to the reaction tank of the wet pulverization and swelling device, thereby fully utilizing the solvent and effectively improving solvent utilization.

[0025] Preferably, the extrusion device adopts a variable pitch spiral extrusion separator, which includes an extrusion barrel and a drive motor. The extrusion barrel is constructed as a cylindrical structure, and the outer sides of the two ends of the extrusion barrel are respectively constructed with an inlet and an outlet, and the middle part of the extrusion barrel is constructed with a reflux port. A rotating shaft is provided in the extrusion barrel, and one end of the rotating shaft is connected to the drive motor for transmission. A spiral blade adapted to the extrusion barrel is provided on the rotating shaft in the extrusion barrel, and the pitch of the spiral blade gradually decreases from the inlet to the middle of the extrusion barrel; and the pitch of the spiral blade gradually increases from the middle of the extrusion barrel to the outlet.

[0026] Compared with the existing technology, the wet crushing and swelling equipment for pulp and the preparation system of fiber spinning solution provided by the utility model are used in the process of industrially preparing lyocell fiber spinning solution, which can simultaneously realize the wet crushing and swelling of pulp, and has the advantages of lower cost and higher efficiency. It can not only eliminate the hidden danger of dust generated during the crushing process of pulp, but also promote more uniform dispersion of cellulose in the solvent, thereby achieving a more sufficient and uniform swelling effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 This is a structural schematic diagram of a wet crushing and swelling device provided in an embodiment of the utility model.

[0029] Figure 2 for Figure 1 Cross-sectional view at AA in the middle.

[0030] Figure 3 for Figure 1 A local enlarged schematic diagram of point I in the middle.

[0031] Figure 4 This is a structural schematic diagram of a preparation system provided in Example 4 of the present utility model.

[0032] Explanation of the marks in the figure: wet crushing and swelling equipment 1, reaction tank 11, insulation structure 12, motor 13, reducer 14, coupling 15, support frame 16, support 17; tank body 21, tank cover 22, frame 23, feeding port 24, solvent inlet 25, discharge port 26, valve 27; stirring shaft 31, mounting block 32, moving knife component 33, center block 34, static knife component 35, serrated structure 36, guide tube 37, bracket 38, impeller 39; first paddle 4; second paddle 5; hopper 61, extrusion device 62, crushing and grinding equipment 63, screw conveyor 64, dissolving device 65; driving motor 71, extrusion cylinder 72, inlet 73, outlet 74, reflux port 75, rotating shaft 76, spiral blade 77; solvent recovery tank 81, delivery pump 82, filter 83, pipeline 84. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the utility model for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0034] Example 1

[0035] This embodiment provides a wet crushing and swelling device for pulp, which is used to simultaneously wet crush and swell the pulp raw material, and includes a reaction tank 11, a motor 13, a stirring mechanism, and a heat insulation structure 12.

[0036] like Figure 1As shown, the reaction tank 11 includes a tank body 21 with a reaction chamber, a tank cover 22 that closes the top of the tank body 21, and a frame 23 that supports the tank body 21. The tank cover 22 is installed on the top of the tank body 21. During implementation, the tank cover 22 can be detachably installed on the tank body 21 by fasteners such as bolts or screws to facilitate assembly and subsequent maintenance.

[0037] like Figure 1 As shown, the tank cover 22 is constructed with a feeding port 24 for adding pulp raw materials, a solvent inlet 25 for adding solvent, and an assembly port adapted for the stirring mechanism; accordingly, the bottom of the tank body 21 is provided with a discharge port 26, as shown in the figure, and a valve 27 is provided at the discharge port 26. The valve 27 can preferably adopt a gate valve, a ball valve, etc., so that the valve 27 can be used to control the opening and closing of the discharge port 26.

[0038] like Figure 1 As shown, the heat-insulating structure 12 is disposed outside the tank body 21 and is primarily used to provide a stable temperature condition for the reaction tank 11. In practice, the heat-insulating structure 12 may employ an existing jacket structure so as to precisely control the temperature within the reaction tank 11, thereby ensuring that the wet pulverization and swelling apparatus 1 achieves a better swelling effect. Of course, in other embodiments, the heat-insulating structure 12 may further include a heat-insulating layer, and the material of the heat-insulating layer may include heat-insulating cotton, etc., which merely serves the purpose of heat preservation.

[0039] like Figure 1 As shown, in this embodiment, the stirring mechanism includes a stirring shaft 31, a moving blade assembly, a stationary blade assembly, a guide tube 37 and an impeller 39. The motor 13 can be installed on the support frame 16. The support frame 16 can be installed on the top of the tank cover 22 or on the frame 23. The stirring shaft 31 is arranged vertically, and the upper end of the stirring shaft 31 is connected to the output shaft of the motor 13. During implementation, the motor 13 can be connected to the stirring shaft 31 through a transmission mechanism, which can be a coupling 15, a reducer 14, a belt transmission mechanism or a chain transmission mechanism. For example, Figure 1 As shown, the output shaft of the motor 13 is connected to the reducer 14, and the reducer 14 is fixed to the tank cover 22 through the support frame 16. The output shaft of the reducer 14 is connected to the upper end of the stirring shaft 31 through the coupling 15, and the reducer 14 plays a role in reducing the speed and increasing the torque.

[0040] like Figure 1 As shown, the lower end of the stirring shaft 31 extends into the reaction chamber of the tank body 21 through the assembly port. During implementation, a sealing structure is also configured at the assembly port, and the sealing structure can be implemented using existing technology. Figure 1As shown, the guide tube 37 is fixedly arranged in the reaction chamber of the reaction tank 11, and the lower end of the stirring shaft 31 is at least inserted into the guide tube 37. In implementation, the guide tube 37 can be constructed as a cylindrical structure, and the central axis of the guide tube 37 can coincide with the central axis of the stirring shaft 31; in implementation, the guide tube 37 can be fixed to the side wall of the tank body 21 by the bracket 38, as shown in FIG. Figure 1 As shown, multiple groups of brackets 38 can be arranged along the height direction of the guide tube 37, which not only can be more firmly fixed to the guide tube 37, avoiding shaking or deformation of the upper end of the guide tube 37, and improving reliability, but also the brackets 38 are arranged between the guide tube 37 and the side wall of the tank body 21, and will not occupy the space between the guide tube 37 and the bottom of the tank body 21, and will neither interfere with the installation and operation of the impeller 39 nor form turbulence between the guide tube 37 and the bottom of the tank body 21, which is more conducive to driving the material to circulate in the vertical direction.

[0041] In this embodiment, the static knife assembly is arranged in the guide cylinder 37. The static knife assembly includes a center block 34 and a plurality of static knife components 35. The center block 34 is configured with a center hole for passing the stirring shaft 31. The inner diameter of the center hole is larger than the outer diameter of the stirring shaft 31. Figure 1 and Figure 2 As shown, the center block 34 is sleeved on the outside of the stirring shaft 31, so that the stirring shaft 31 can rotate relative to the center block 34; one end of the static blade component 35 is connected to the center block 34, and the other end is connected to the guide tube 37. In practice, the static blade components 35 can be evenly distributed along the circumferential direction of the stirring shaft 31, and the static blade components 35 can be arranged along the radial direction of the stirring shaft 31. The upper end of the static blade component 35 is constructed with a sawtooth structure 36, as shown in FIG. Figure 1 and Figure 2 As shown, the serration structure 36 is arranged along the length direction of the stationary knife component 35, which is more conducive to crushing the pulp. On this basis, the lower end of the stationary knife component 35 is further constructed as a serration structure 36, or the side of the stationary knife component 35 is further constructed as a serration structure 36, which is also conducive to crushing the pulp.

[0042] In this embodiment, the moving knife assembly is also arranged in the guide tube 37. The moving knife assembly is constructed to adapt to the static knife assembly. The moving knife assembly includes a mounting block 32 for connecting to the stirring shaft 31 and a moving knife component 33 connected to the mounting block 32. During implementation, the mounting block 32 can be constructed as a cylindrical structure. The mounting block 32 is sleeved on the stirring shaft 31. The mounting block 32 can be fixed to the stirring shaft 31 by welding, or can be detachably installed on the stirring shaft 31 by fasteners such as bolts or screws. The number of moving knife components 33 can be one, two, three, four, etc. For example, the mounting block 32 of the moving knife assembly is provided with at least three moving knife components 33, and each moving knife component 33 is evenly distributed along the circumferential direction of the mounting block 32, so that each moving knife component 33 can be evenly distributed along the circumferential direction of the stirring shaft 31, which is conducive to achieving a better stirring and crushing effect. During implementation, a serrated structure 36 is also constructed along the length direction of the moving knife component 33, such as Figure 1 and Figure 2 As shown, it is more conducive to breaking the pulp.

[0043] When implementing, Figure 1 and Figure 2 As shown, the movable knife assembly is arranged at a position adapted to the stationary knife assembly, and the movable knife assembly can rotate relative to the stationary knife assembly under the drive of the stirring shaft 31, so that the movable knife assembly and the adjacent stationary knife assembly can form a shear fit in the guide tube 37 (specifically, the movable knife component 33 in the movable knife assembly and the stationary knife component 35 in the stationary knife assembly form a shear fit), and form a shear fit area, which can not only further crush the pulp by shear fit and eliminate the hidden danger of dust generated by the pulp during the crushing process, but also promote a more uniform dispersion of cellulose in the solvent, thereby achieving a more sufficient and uniform swelling effect.

[0044] like Figure 1 and Figure 2 As shown, during implementation, the stationary knife assembly is arranged at the middle and / or lower position of the corresponding guide cylinder 37, and correspondingly, the movable knife assembly is also arranged at the middle and / or lower position of the corresponding guide cylinder 37; at these positions, the pulp has been fully in contact with the solvent and has swelled, and the toughness is greatly reduced, which not only makes it easier to crush the pulp, but also makes the shear cooperation between the movable knife assembly and the stationary knife assembly less likely to get stuck.

[0045] In practice, the serration structure 36 on the moving blade component 33 can be configured to match the serration structure 36 on the stationary blade component 35 to achieve a more efficient shearing fit. Figure 1-Figure 3As shown, specifically, the width direction of the movable blade component 33 is inclined to the horizontal direction, so that the serrated structure 36 constructed on the movable blade component 33 is also inclined to the horizontal direction, so that the movable blade component 33 can provide a downward thrust for the liquid in the guide tube 37 during the rotation process (playing the role of a propeller), pushing the liquid in the guide tube 37 to flow from top to bottom, which can avoid blockage in the guide tube 37 and drive the liquid to circulate along the height direction of the guide tube 37, which is more conducive to uniform swelling.

[0046] like Figure 1-Figure 3 As shown, in this embodiment, the movable blade component 33 is arranged tilted to the horizontal direction, and the stationary blade component 35 is also arranged tilted to the horizontal direction, and the tilt direction of the movable blade component 33 is opposite to the tilt direction of the movable blade component 33, as shown in FIG. Figure 1-Figure 3 As shown, it is conducive to achieving better shearing coordination and more effective dispersion of cellulose in the liquid, which is conducive to achieving more uniform swelling. In implementation, the movable blade component 33 can adopt a flat plate, an arc plate, a spiral plate or other structures, and correspondingly, the stationary blade component 35 can also adopt a flat plate, an arc plate, a spiral plate or other structures.

[0047] During implementation, at least one moving knife assembly and one stationary knife assembly are required. In a more preferred embodiment, the stirring mechanism is configured with multiple moving knife assemblies and multiple stationary knife assemblies, and the multiple moving knife assemblies and the multiple stationary knife assemblies are staggered along the height direction of the guide cylinder 37, such as Figure 1-Figure 3 As shown, the static knife assembly is provided with movable knife assemblies above and below it, and the static knife assembly and the two adjacent movable knife assemblies can rotate relative to each other, which can not only achieve better shearing effect and higher efficiency, but also help to further improve the uniformity of swelling.

[0048] like Figure 1 As shown, the impeller 39 is arranged on the stirring shaft 31 and is located below the guide tube 37. The impeller 39 rotates synchronously with the stirring shaft 31. The centrifugal force generated by the rotation of the impeller 39 forces the liquid in the guide tube 37 flowing from top to bottom to flow upward between the guide tube 37 and the tank body 21, so that the impeller 39 can assist the liquid in the guide tube 37 to flow from top to bottom, which is more conducive to forming a circulating flow inside and outside the barrel, thereby being more conducive to the full crushing and fully uniform swelling of the pulp.

[0049] In order to improve the stability of the stirring shaft 31, during implementation, the stirring shaft 31 can be connected to the tank body 21 through a bearing. For example, the upper end of the stirring shaft 31 can be connected to the tank cover 22 through a bearing. In order to prevent the lower end of the stirring shaft 31 from swinging, during implementation, a support 17 adapted to the stirring shaft 31 is further provided at the bottom of the tank body 21. The lower end of the stirring shaft 31 can be rotatably constrained to the support 17. Figure 1As shown, the support 17 can be used to effectively constrain the lower end of the stirring shaft 31 to prevent the lower end of the stirring shaft 31 from swinging significantly during rotation, thereby improving the stability of the stirring shaft 31 during rotation.

[0050] Example 2

[0051] During the implementation and use, the pulp raw material is usually flaky dry pulp. The pulp raw material is added to the reaction tank 11 from the feed port 24 above the reaction tank 11, and driven by the liquid in the reaction tank 11, it enters the guide tube 37 from the upper end of the guide tube 37. At this time, the contact time between the pulp and the solvent is relatively short, the pulp is not completely in contact with and soaked in the solvent, and the pulp toughness is relatively high. If this pulp directly enters the shearing area of ​​the moving knife assembly and the static knife assembly for shearing, it will not only cause a significant increase in the load of the motor 13, but also easily cause jamming, which is not conducive to the stable operation of the system. In order to solve this technical problem, in the wet crushing and swelling equipment 1 provided in this embodiment, the stirring mechanism also includes a first crushing assembly, the first crushing assembly is installed on the stirring shaft 31, the first crushing assembly is located in the guide tube 37, and is located above the moving knife assembly, such as Figure 1 As shown, in practice, the first crushing assembly can be positioned at a position corresponding to the middle or upper portion of the guide tube 37 to individually crush the pulp entering the guide tube 37. First, the first crushing assembly breaks the pulp into smaller pieces, making it easier for the pulp to contact the solvent more quickly and thoroughly, soaking and swelling. Second, it can slow down the falling pulp, increasing the time it takes to fall into the matching shear zone below, further facilitating full contact and swelling of the pulp with the solvent. This significantly reduces the toughness of the pulp that falls into the matching shear zone, making it easier to crush and effectively avoiding the problem of sticking.

[0052] In implementation, the structure of the first crushing assembly can be the same as that of the moving blade assembly. For example, in implementation, the first crushing assembly can include a mounting block 32 for connecting to the stirring shaft 31 and a first blade 4 connected to the mounting block 32. The number of the first blades 4 can be multiple, and each first blade 4 is evenly distributed along the circumferential direction of the stirring shaft 31. Similarly, the first blade 4 can be constructed with a serrated structure 36 distributed along its length, such as Figure 1 As shown, this is more conducive to pulp crushing. Similarly, the first blades 4 can also be arranged obliquely to the horizontal direction, which not only further facilitates pulp crushing, but also helps to push the liquid in the guide tube 37 from top to bottom, allowing the crushed pulp to flow to the matching shearing zone below. The number of first crushing components can be determined according to actual needs and will not be detailed here.

[0053] Example 3

[0054] like Figure 1As shown, since the stirring shaft 31 is usually set at the center of the reaction tank 11, the feeding port 24 can only be set at a position deviated from the center of the reaction tank 11, and the pulp raw material is flaky dry pulp, which makes it difficult for the pulp raw material fed from the feeding port 24 to enter the guide tube 37; if the pulp does not enter the guide tube 37 or most of it is between the guide tube 37 and the tank body 21 during feeding, the pulp will easily hang on the bracket 38 of the guide tube 37, making it more difficult for the pulp to enter the guide tube 37, seriously affecting the crushing and swelling. In order to solve this technical problem, the main difference between this embodiment 3 and the above-mentioned embodiment 1 is that in the wet crushing and swelling equipment 1 provided in this embodiment, the stirring mechanism also includes a second crushing component, which is installed on the stirring shaft 31 and is located above the guide tube 37, as shown in FIG. Figure 1 As shown, the second crushing assembly rotates synchronously with the stirring shaft 31. Not only can the second crushing assembly be used to crush the pulp that has not been exposed to the solvent when feeding, but it can also make it easier for the pulp to be thoroughly exposed to the solvent and soaked and swelled more quickly. Moreover, when feeding, the pulp can be allowed to enter the guide tube 37 as much as possible, greatly reducing the possibility of the pulp falling between the guide tube 37 and the tank body 21.

[0055] In practice, the second crushing assembly includes a mounting block 32 for connecting to the stirring shaft 31 and a second blade 5 connected to the mounting block 32. The number of the second blades 5 can be multiple, and each second blade 5 is evenly distributed along the circumferential direction of the stirring shaft 31, such as Figure 1 As shown; in practice, the structure of the second blade 5 can be the same as or different from that of the movable blade member 33 in the movable blade assembly. For example, in this embodiment, the second blade 5 can be arranged horizontally, and the side of the second blade 5 can also be provided with a serrated structure 36 distributed along its length, which is conducive to achieving a better crushing effect on the falling pulp.

[0056] In practice, the second blade 5 should have a sufficient length to cover the feed port 24. Figure 1 As shown, the pulp fed from the feed port 24 can directly fall onto the rotating second crushing assembly, so that the second crushing assembly can be used to crush the fed pulp for the first time. After the pulp enters the guide tube 37, the first crushing assembly can be used to crush the pulp for the second time, so that the pulp falling into the coordinated shearing zone is fully in contact with the solvent and swells, and its toughness is greatly reduced, so that it can be crushed by the shearing coordination of the moving knife assembly and the static knife assembly in the coordinated shearing zone, which is more conducive to the pulp to achieve more complete and uniform swelling in the wet crushing swelling equipment 1; finally, the liquid in the reaction tank 11 is discharged from the discharge port 26 at the bottom of the tank body 21 to obtain a uniformly swollen cellulose suspension.

[0057] Example 4

[0058] This embodiment provides a system for industrially preparing lyocell fiber spinning solution, which includes the aforementioned wet crushing and swelling device 1, an extrusion device 62, a crushing and grinding device 63, and a dissolving device 65. The wet crushing and swelling device 1, the extrusion device 62, the crushing and grinding device 63, and the dissolving device 65 are connected in sequence. Figure 4 As shown, the main function of the wet crushing and swelling device 1 is to wet crush and swell the pulp raw material, so that the wet crushing and swelling are completed simultaneously in the same device. Specifically, in actual use, the pulp raw material is directly added into the wet crushing and swelling device 1. The wet crushing and swelling device 1 can realize the wet crushing and swelling of the pulp simultaneously. It is an integrated device that can simultaneously realize the wet crushing of the pulp raw material and the swelling of the cellulose in the pulp raw material, ensuring that a low-concentration cellulose suspension is obtained.

[0059] like Figure 4 As shown, a receiving hopper 61 is further provided at the inlet 73 of the extrusion device 62 to receive the cellulose suspension discharged from the wet crushing and swelling device 1 , thereby achieving communication between the wet crushing and swelling device 1 and the extrusion device 62 .

[0060] In this embodiment, the main function of the extrusion device 62 is to extrude the uniformly swollen cellulose suspension, and to separate part of the solvent in the cellulose suspension by extrusion, thereby achieving the purpose of increasing the cellulose concentration in the suspension. In this embodiment, the extrusion device 62 can preferably adopt a variable pitch spiral extrusion separator, such as Figure 4 As shown, the screw extrusion separator includes an extrusion barrel 72 and a drive motor 7113. The extrusion barrel 72 is constructed as a cylindrical structure. The outer sides of the two ends of the extrusion barrel 72 are respectively constructed with an inlet 73 and an outlet 74. The middle part of the extrusion barrel 72 is constructed with a reflux port 75. A rotating shaft 76 is provided in the extrusion barrel 72. One end of the rotating shaft 76 is transmission-connected to the drive motor 7113. A spiral blade 77 adapted to the extrusion barrel 72 is provided on the rotating shaft 76 in the extrusion barrel 72 so as to transport the cellulose suspension in the direction from the inlet 73 to the outlet 74; the pitch of the spiral blade 77 gradually decreases from the inlet 73 to the middle of the extrusion barrel 72; the pitch of the spiral blade 77 gradually increases from the middle of the extrusion barrel 72 to the outlet 74, so as to separate part of the solvent in the cellulose suspension by extrusion and increase the concentration of cellulose in the suspension to within a preset range; the separated solvent is discharged from the screw extrusion separator via the reflux port 75.

[0061] like Figure 4As shown, the preparation system further includes a solvent recovery tank 81, a delivery pump 82, and a filter 83. The discharge port is connected to the solvent recovery tank 81, which is connected to the filter 83 via the delivery pump 82. The filter 83 is connected to the solvent inlet 25 of the wet pulverization and swelling apparatus 1 via a pipeline 84. The solvent recovery tank 81 is used to store the recovered solvent, the delivery pump 82 is used to provide delivery power, and the filter 83 is used to filter the recovered solvent to remove residual pulp impurities, thereby obtaining a relatively pure solvent. The solvent can then be re-delivered to the reaction tank 11 of the wet pulverization and swelling apparatus 1 to fully utilize the solvent and effectively improve the solvent utilization rate.

[0062] In this embodiment, the crushing and grinding device 63 primarily grinds the high-concentration cellulose suspension exiting the screw extruder. This crushing and grinding not only makes the swollen high-concentration cellulose suspension more uniform, but also significantly improves the dissolution efficiency and uniformity of the spinning solution, thereby enhancing spinnability and facilitating subsequent spinning. In practice, the crushing and grinding device 63 can be implemented using existing technologies, and detailed examples are not provided here.

[0063] During implementation, the crushing and grinding equipment 63 and the dissolving device 65 can be connected through a screw conveyor 64, such as Figure 4 As shown, the outlet 74 of the crushing and grinding device 63 is connected to the screw conveyor 64, and the screw conveyor 64 can be connected to the dissolving device 65 through the pipeline 84, as shown in FIG. Figure 4 As shown, a screw conveyor 64 is used to transport the crushed and ground high-concentration cellulose suspension to a dissolving device 65.

[0064] In this embodiment, the main function of the dissolving device 65 is to heat and evaporate the solvent in the high-concentration cellulose suspension under vacuum and negative pressure conditions to dissolve the cellulose and obtain a lyocell fiber spinning solution. In practice, the dissolving device 65 uses a vertical thin film evaporator, such as Figure 4 shown.

[0065] Compared to existing technologies, this preparation system, on the one hand, by configuring the wet pulverization and swelling device 1 at the front end, not only avoids the hidden danger of dust generation during the pulp pulverization process, but also solves the problem of poor pulp swelling performance at high solvent concentrations and high pulp concentrations, achieving more uniform and sufficient swelling of the pulp raw material in a simple manner. On the other hand, after using the extrusion device 62 to increase the cellulose concentration in the cellulose suspension, the pulverization and grinding further improves the swelling uniformity of the pulp raw material, effectively preventing the occurrence of "white core" during the swelling process and uneven dissolution.

[0066] The above is only a specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A wet crushing and swelling device for pulp, comprising a reaction tank, a motor and a stirring mechanism, wherein a reaction chamber is constructed in the reaction tank, characterized in that: The stirring mechanism includes a stirring shaft, a guide tube, a moving knife assembly arranged in the guide tube, and a stationary knife assembly arranged in the guide tube, wherein: The guide tube is arranged in the reaction chamber through a bracket; The stirring shaft is arranged vertically, the upper end of the stirring shaft is connected to the motor, the lower end of the stirring shaft extends into the reaction chamber, and the lower end of the stirring shaft is at least inserted into the guide cylinder; The static blade assembly includes a center block and multiple static blade components. The center block is sleeved on the outside of the agitator shaft. One end of the static blade component is connected to the center block and the other end is connected to the guide tube. The static blade components are evenly distributed along the circumference of the agitator shaft. The moving knife assembly is constructed to adapt to the static knife assembly and is located at the position adapted to the static knife assembly. The moving knife assembly includes a mounting block for connecting to the stirring shaft and a plurality of moving knife components connected to the mounting block. The moving knife components are evenly distributed along the circumferential direction of the stirring shaft; the moving knife assembly is used to rotate relative to the static knife assembly under the drive of the stirring shaft, so that the moving knife assembly and the adjacent static knife assembly form a shear fit in the guide tube.

2. The wet crushing and swelling device for pulp according to claim 1, characterized in that: The stirring mechanism is equipped with a plurality of movable knife assemblies and a plurality of stationary knife assemblies, and the plurality of movable knife assemblies and the plurality of stationary knife assemblies are respectively arranged in a staggered manner along the height direction of the guide tube.

3. The wet crushing and swelling device for pulp according to claim 1, characterized in that: The stationary blade assembly is arranged at a position corresponding to the middle and / or lower portion of the guide cylinder; the movable blade assembly is also arranged at a position corresponding to the middle and / or lower portion of the guide cylinder; And / or, the movable blade component is arranged obliquely with respect to the horizontal direction to provide a downward thrust. And / or, the stirring mechanism further includes an impeller, which is arranged on the stirring shaft and located below the guide cylinder, and the impeller rotates synchronously with the stirring shaft.

4. The wet crushing and swelling device for pulp according to claim 1, characterized in that: At least the upper end of the static blade component is configured with a sawtooth structure, and the sawtooth structure is arranged along the length direction of the static blade component; And / or, a serration structure is constructed along the length direction of the movable blade component.

5. The wet crushing and swelling device for pulp according to any one of claims 1 to 4, characterized in that: The reaction tank is also constructed with a feeding port for adding pulp raw materials, a solvent inlet for adding solvent, an assembly port and a discharge port. The feeding port, solvent inlet, assembly port and discharge port are respectively connected to the reaction chamber, and the stirring shaft extends into the reaction chamber through the assembly port.

6. The wet crushing and swelling device for pulp according to claim 1, characterized in that: The stirring mechanism also includes a first crushing assembly, which is installed on the stirring shaft. The first crushing assembly is located in the guide tube and above the movable knife assembly. The first crushing assembly is arranged at a position corresponding to the middle or upper part of the guide tube.

7. The wet crushing and swelling device for pulp according to claim 6, characterized in that: The first crushing assembly includes a mounting block for connecting to a stirring shaft and a plurality of first blades connected to the mounting block, wherein the first blades are evenly distributed along the circumferential direction of the stirring shaft; the first blades are arranged obliquely to the horizontal direction to provide downward thrust; the first blades are also constructed with a serrated structure distributed along their length.

8. The wet crushing and swelling device for pulp according to claim 5, characterized in that: The stirring mechanism further includes a second crushing assembly, which is mounted on the stirring shaft and located above the guide cylinder. The second crushing assembly rotates synchronously with the stirring shaft, and the rotation range of the second crushing assembly covers the feeding port. The second crushing assembly includes a mounting block for connecting to the stirring shaft and a plurality of second blades connected to the mounting block, and the second blades are evenly distributed along the circumferential direction of the stirring shaft.

9. A system for preparing fiber spinning solution, characterized in that: It comprises an extrusion device, a crushing and grinding device, a dissolving device and the wet crushing and swelling device according to any one of claims 1 to 8, wherein the wet crushing and swelling device is connected to the extrusion device, the extrusion device is connected to the crushing and grinding device, and the crushing and grinding device is connected to the dissolving device.

10. The fiber spinning solution preparation system according to claim 9, characterized in that: It also includes a screw conveyor, the crushing and grinding equipment is connected to the screw conveyor, and the screw conveyor is connected to the dissolving device through a pipeline; It also includes a solvent recovery tank, a delivery pump, and a filter, wherein the extrusion device is constructed with a reflux port for discharging the solvent, the reflux port is connected to the solvent recovery tank, the solvent recovery tank is connected to the filter through the delivery pump, and the filter is connected to the feeding port through a pipeline.

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