Circulating pulping system and pulping method

Abstract

This invention discloses a circulating pulping system and method, comprising a circulating tank, a dispersing device, a powder tank, and a liquid tank. The dispersing device is connected to the circulating tank via a circulating pipeline, the powder tank is connected to the circulating tank via a powder inlet pipeline, and the liquid tank is connected to the circulating tank via a liquid inlet pipeline. The circulating tank has several liquid inlets and several spray nozzles, which are connected to the liquid inlet pipeline via inlet branch pipes. The liquid inlets are connected to the inner cavity of the circulating tank, and the spray nozzles are equipped with spray devices. During pulping, the solution in the liquid tank is injected into the circulating tank in stages, and the solution is injected into the circulating tank in a single stage through the liquid inlet and / or the spray device. This invention uses a high-pressure spray device to flush and recover floating powder, improving the effective utilization rate of the powder, ensuring the mixing effect of the pulp, and improving the precision and quality of the pulp.

Description

Technical Field

[0001] This invention relates to the field of pulping equipment technology, specifically a circulating pulping system and pulping method. Background Technology

[0002] The circulating high-efficiency pulping system is used for powder-liquid mixing and pulp dispersion to meet the production needs of high-quality pulp with low viscosity, high solid content, and high stability.

[0003] In conventional circulating pulping systems, powder is typically fed into a dispersion unit, where it is mixed with the solution before being circulated for pulping. This production process frequently encounters issues such as material blockage, backflow, and material adhesion. Material blockage requires shutdown for cleaning, impacting production efficiency and cycle time. Backflow can lead to pulp overflow, which may pose safety risks. Material adhesion can affect the accuracy of the material formulation, resulting in a decline in product quality. Summary of the Invention

[0004] In response to the shortcomings of existing circulating pulping processes, the applicant provides a reasonably structured circulating pulping system and pulping method, which optimizes the pulping process, avoids material blockage, backflow, and sticking, improves the stability and reliability of system operation, and ensures product quality and pulping efficiency.

[0005] The technical solution adopted in this invention is as follows: A circulating pulping system includes a circulating tank device, a dispersing device, a powder tank device, and a liquid tank; the dispersing device is connected to the circulating tank device through a circulating pipeline, the powder tank device is connected to the circulating tank device through a powder inlet pipeline, and the liquid tank is connected to the circulating tank device through a liquid inlet pipeline. The circulating tank device is equipped with several liquid inlets and several spray nozzles. The liquid inlets and spray nozzles are connected to the liquid inlet pipeline through liquid inlet branch pipes. The liquid inlets are connected to the inner cavity of the circulating tank device, and the spray nozzles are equipped with spray devices. During pulping, the solution in the liquid tank is injected into the circulating tank device in several batches. The solution is injected into the circulating tank device once through the liquid inlet and / or the spray device.

[0006] As a further improvement to the above technical solution: The spray system can be adjusted by lifting and / or rotating.

[0007] The dispersing device is equipped with a dispersing assembly, which includes a dispersing rotor and a dispersing stator. The dispersing rotor is sleeved on the main shaft, and the dispersing stator is fixed on the housing assembly. A dispersion ring is provided on both the dispersion rotor and the dispersion stator, and several flow holes are provided on the dispersion ring; Alternatively, several blades are provided on the dispersed rotor and dispersed stator respectively. The blades are divided into several levels, with several blades in each level. The blades of the several levels are distributed at intervals from top to bottom along the axial direction. The rotor blades and stator blades are inclined downwards respectively, and the inclination direction of the stator blades is opposite to that of the rotor blades. Alternatively, the dispersed rotor may have several convex ridges and concave valleys arranged circumferentially, with the convex ridges and concave valleys interspersed alternately, and the dispersed stator may have several convex ridges and concave valleys arranged circumferentially, with the convex ridges and concave valleys interspersed alternately; there may be a gap between the convex ridges of the dispersed rotor and the convex ridges of the dispersed stator; and several rotor flow holes may be opened on the dispersed rotor.

[0008] A guide plate is installed inside the slurry inlet of the dispersion device. The guide plate is sleeved on the main shaft and has several guide blades. The ratio of the flow channel area S1 formed between the guide plate and the side wall of the slurry inlet to the flow channel area S2 of the slurry inlet is: 0.6≤S1 / S2<1.0.

[0009] The circulating tank device has a vertically installed stirring mechanism and a dispersing mechanism inside the circulating tank, and a cooling jacket is installed on the wall of the circulating tank; the powder tank device is equipped with a mixing mechanism and a quantitative feeding device.

[0010] The circulation pipeline is equipped with a circulation pump and a cooling device; the liquid inlet pipeline is equipped with a liquid inlet pump; and control valves are installed on the circulation pipeline and the powder inlet pipeline respectively.

[0011] A pulping method using the above-mentioned circulating pulping system includes, Step 1: Add a certain amount of solution to the circulation tank device; Step 2: Disperse and circulate the injected solution; Step 3: Add powder to the circulating tank device; Step 4: Spray the remaining solution into the circulation tank device; Step 5: High-speed circulation to complete pulping.

[0012] As a further improvement to the above technical solution: In step one, the ratio of the amount of solution added (a) to the total amount of solution required (b) is 1 > a / b ≥ 0.7. In step four, the remaining amount of solution sprayed is c, and a + c = b.

[0013] The remaining solution in step four is sprayed into the circulation tank in several batches, with a certain time interval between the two sprays.

[0014] In step one, the volume of the solution added to the circulation tank accounts for 30% of the circulation tank's volume; in step three, the total volume of the powder added to the solution and the powder accounts for 80% of the circulation tank's volume.

[0015] The present invention has at least the following beneficial effects: (1) The present invention uses a high-pressure spraying device to flush and recover floating powder, which avoids powder waste and quality deviation caused by powder adhering to the tank wall and tank top, improves the effective utilization rate of powder, ensures the mixing effect of slurry, and improves the precision and quality of slurry.

[0016] (2) The solution of the present invention is added in stages, which not only ensures the uniform mixing of solution components, but also utilizes the fluidity of the solution to realize the spraying and recovery of floating powder, thereby improving the rationality and economy of the process and reducing the waste of powder.

[0017] (3) The process of the present invention is highly controllable. The parameters such as solution addition, powder metering, spraying times and dispersion speed of each step can be precisely controlled, which can adapt to the preparation needs of different types of slurry. The process is highly adaptable and easy to promote and apply on a large scale in the industry.

[0018] (4) The present invention uses a large-space circulating tank, which enables various powders to be added quickly. Combined with the disturbance effect of the solution vortex, the powder is quickly wetted, which effectively solves the problems of slow powder addition, insufficient wettability and easy agglomeration in conventional pulping processes.

[0019] (5) The present invention further improves the dispersion uniformity of the slurry by high-speed circulation dispersion, ensuring that the quality and precision of the finished slurry meet the requirements. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the pulping system architecture of the present invention.

[0021] Figure 2 This is a schematic diagram of the circulating tank device.

[0022] Figure 3 This is the first embodiment of the dispersion device.

[0023] Figure 4 The diagram shows the structure of the guide plate. (a) is the right view and (b) is the front view.

[0024] Figures 5 to 8 This is a second embodiment of the dispersing device. Figure 5 This is a schematic diagram of the overall dispersing device in this embodiment. Figure 6 This is a schematic diagram of the dispersed rotor in this embodiment. Figure 7 This is a schematic diagram of the distributed stator in this embodiment. Figure 8 This is a cross-sectional view of the axial section of the dispersion component.

[0025] Figures 9 to 12 This is a third embodiment of the dispersion device. Figure 9 This is a schematic diagram of the overall dispersing device in this embodiment. Figure 10This is a schematic diagram of the dispersed rotor in this embodiment. Figure 11 This is a schematic diagram of the distributed stator in this embodiment. Figure 12 This is a radial cross-sectional view of the dispersed component.

[0026] In the picture: 1. Circulating tank device; 11. Circulating tank body; 111. Powder inlet; 112. Liquid inlet; 113. Mixing inlet; 114. Mixing outlet; 115. Cooling jacket; 116. Spray nozzle; 12. Agitator; 121. Agitator paddle; 122. Agitator shaft; 123. Agitator motor; 13. Dispersion mechanism; 131. Dispersion disc; 132. Dispersion shaft; 133. Dispersion motor; 14. Spray device; 2. Dispersion device; 21. Shell assembly; 211. Dispersion chamber; 212. Output chamber; 213. Slurry inlet; 2131. Feed port; 214. Slurry outlet; 22. Main shaft; 23. Dispersion rotor; 231. Rotor base plate; 232. Rotor dispersion ring; 2321. Rotor flow hole; 233. Sleeve; 234. Rotor blade; 235. Outer convex ridge; 236. Outer concave valley; 24. Dispersion stator; 241. Stator base plate; 2411. Liquid passage; 242. Stator dispersion ring; 2421. Stator flow hole; 243. Stator cylinder; 244. Stator blade; 245. Inner convex ridge; 246. Inner concave valley; 25. Conveying impeller; 26. Guide plate; 261. Conical plate; 262. Guide vane; 3. Powder tank device; 31. Powder tank body; 32. Mixing mechanism; 33. Mixing motor; 34. Quantitative feeding device; 4. Liquid tank; 5. Circulation pump; 6. Cooling device; 7. Inlet pump; 8. Control valve; 100. Circulation pipeline; 101. Discharge pipeline; 102. Feed pipeline; 200. Powder inlet pipeline; 300. Liquid inlet pipeline; 301. Liquid inlet branch pipeline. Detailed Implementation

[0027] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0028] like Figure 1 As shown, the circulating pulping system of the present invention includes a circulating tank device 1, a dispersing device 2, a powder tank device 3, and a liquid tank 4. The dispersing device 2 is connected to the circulating tank device 1 via a circulating pipeline 100, the powder tank device 3 is connected to the circulating tank device 1 via a powder inlet pipeline 200, and the liquid tank 4 is connected to the circulating tank device 1 via a liquid inlet pipeline 300. A circulating pump 5 and a cooling device 6 are installed on the circulating pipeline 100; a liquid inlet pump 7 is installed on the liquid inlet pipeline 300; and control valves 8 are respectively installed on the circulating pipeline 100 and the powder inlet pipeline 200.

[0029] like Figure 2As shown, the top of the circulating tank 11 of the circulating tank device 1 is provided with a powder inlet 111, several liquid inlets 112, several spray nozzles 116, and a mixing inlet 113, and the bottom is provided with a mixing outlet 114. The discharge pipe 101 of the circulating pipeline 100 is connected to the mixing outlet 114, the feed pipe 102 is connected to the mixing inlet 113, the powder inlet pipe 200 is connected to the powder inlet 111, and the several liquid inlets 112 and several spray nozzles 116 are respectively connected to the liquid inlet pipe 300 through the liquid inlet branch pipe 301. A control valve 8 is provided on the liquid inlet branch pipe 301. The liquid inlet 112 is directly connected to the inner cavity of the circulation tank 11. A spray device 14 is connected to the spray port 116 and is installed inside the circulation tank 11. The spray device 14 can be adjusted in angle and direction by lifting and / or rotating to thoroughly flush the tank cavity, tank wall, tank top, inlet and outlet ports, and pipe interfaces of the circulation tank 11. A cooling jacket 115 is installed on the wall of the circulation tank 11. Cooling medium is circulated through the cooling jacket 115 to cool the material inside the tank. A stirring mechanism 12 and a dispersing mechanism 13 are vertically installed inside the circulation tank 11. The stirring mechanism 12 and the dispersing mechanism 13 stir, mix, and disperse the material inside the tank. The stirring mechanism 12 includes a stirring paddle 121, a stirring shaft 122, and a stirring motor 123. The stirring paddle 121 is connected to the bottom of the stirring shaft 122, which is vertically inserted into the circulation tank 11 with its upper end extending out of the circulation tank 11. The stirring motor 123 is connected to the top of the stirring shaft 122. The dispersing mechanism 13 includes several dispersing discs 131, a dispersing shaft 132, and a dispersing motor 133. The several dispersing discs 131 are installed at the lower part of the dispersing shaft 132, which is vertically inserted into the circulation tank 11 with its upper end extending out of the circulation tank 11. The dispersing motor 133 is connected to the top of the dispersing shaft 132.

[0030] like Figure 1 As shown, the powder tank device 3 has a mixing mechanism 32 inside the powder tank body 31. The mixing mechanism 32 is connected to a mixing motor 33, which can drive the mixing mechanism 32 to mix the powder fed into the powder tank body 31. The powder outlet of the powder tank body 31 is connected to the powder inlet pipe 200, and a quantitative feeding device 34 is provided at the powder outlet.

[0031] The dispersing device 2 applicable to the circulating pulping system of the present invention can have many different implementations. The structures of several different dispersing devices 2 are further described below.

[0032] The first embodiment of the dispersing device 2 is described in detail below. Figure 3 , Figure 4 As shown.

[0033] The housing assembly 21 of the dispersion device 2 is provided with a dispersion chamber 211 and an output chamber 212. The housing assembly 21 is provided with an axial slurry inlet 213 that communicates with the dispersion chamber 211 and a radial slurry outlet 214 that communicates with the output chamber 212.

[0034] The dispersion device 2 has a dispersion assembly inside its dispersion chamber 211. The dispersion assembly includes a dispersion rotor 23 and a dispersion stator 24. The dispersion rotor 23 is mounted on the main shaft 22, and the dispersion stator 24 is fixed to the housing assembly 21. The dispersion rotor 23 has a rotor base plate 231 arranged radially, and at least one rotor dispersion ring 232 extends axially from the rotor base plate 231. The rotor dispersion ring 232 has several rotor flow holes 2321. The dispersion stator 24 has a stator base plate 241 arranged radially, and a liquid passage 2411 is formed on the stator base plate 241. The liquid passage 2411 connects the dispersion chamber 211 with the output chamber 212 or the slurry inlet 213. At least one stator dispersion ring 242 extends axially from the stator base plate 241, and the stator dispersion ring 242 has several stator flow holes 2421. The rotor dispersion ring 232 of the dispersion rotor 23 and the stator dispersion ring 242 of the dispersion stator 24 are distributed radially in an alternating pattern.

[0035] The output chamber 212 of the dispersing device 2 is provided with a conveying impeller 25, which is sleeved on the main shaft 22.

[0036] A guide plate 26 is provided inside the slurry inlet 213 of the dispersing device 2, near the dispersing chamber 211. The guide plate 26 is sleeved on the end of the main shaft 22. The guide plate 26 includes a conical plate 261 and several guide vanes 262. The conical plate 261 is conical, with the apex facing the feed port 2131 of the slurry inlet 213 and the base facing the dispersing chamber 211. Several guide vanes 262 are evenly arranged circumferentially on the conical surface of the conical plate 261. The guide vanes 262 are arc-shaped, with the arc convex forward in the direction of rotation of the guide plate 26. When the guide plate 26 rotates, it generates a suction force on the slurry, causing the slurry to enter the dispersing chamber 211 at an accelerated speed. The ratio of the flow channel area S1 formed between the guide plate 26 and the side wall of the slurry inlet 213 to the flow channel area S2 of the slurry inlet 213 is: 0.6 ≤ S1 / S2 < 1.0, where S1 is less than S2. When the slurry flows to the outer part of the guide plate 26, due to the smaller flow channel area, a certain back pressure is generated at this point. The back pressure will further accelerate the slurry into the dispersion chamber 211. Under the action of the guide plate 26, the slurry accelerates into the dispersion chamber 211, and the slurry will flow through the dispersion component at a higher initial velocity for dispersion, which is beneficial to improving the dispersion effect and dispersion efficiency of the slurry.

[0037] The second embodiment of the dispersing device 2 is described in detail below. Figures 5 to 8 As shown.

[0038] Unlike the first embodiment, the dispersion device 2 in this embodiment uses a different dispersion component, which includes a dispersion rotor 23 and a dispersion stator 24.

[0039] The dispersed rotor 23 includes a sleeve 233 and several rotor blades 234. The sleeve 233 is fitted onto the main shaft 22, and the rotor blades 234 extend radially outward and are disposed on the outer wall of the sleeve 233. The rotor blades 234 are divided into several stages, with several blades in each stage. The stages of rotor blades 234 are distributed axially from top to bottom at intervals, and the blades 234 in each stage are evenly distributed circumferentially. The number of rotor blades 234 in each stage is the same, and the circumferential positions of the rotor blades 234 in each stage are the same. The rotor blades 234 are straight blades, and their surfaces are inclined downward from left to right at an angle of α, where α = 20–80°.

[0040] The distributed stator 24 includes a stator cylinder 243 and a plurality of stator blades 244. The stator cylinder 243 is fixed to the housing assembly 21, and the plurality of stator blades 244 extend radially inward and are disposed on the inner wall surface of the stator cylinder 243. The plurality of stator blades 244 are divided into several stages, with a plurality of blades in each stage. The stator blades 244 in the stages are distributed at intervals from top to bottom along the axial direction, and the plurality of stator blades 244 in each stage are evenly distributed circumferentially. The number of stator blades 244 in each stage is the same, and the circumferential positions of the stator blades 244 in each stage are the same. The number of stator blades 244 in each stage is the same as the number of rotor blades 234 in each stage. The stator blades 244 are straight blades, and their blade surfaces are inclined downward from right to left. The inclination direction of the stator blades 244 is opposite to the inclination direction of the rotor blades 234. The inclination angle of the stator blades 244 is β, where β = -80° to -20°, and α ≥ -β.

[0041] The rotor blades 234 of the distributed rotor 23 and the stator blades 244 of the distributed stator 24 are distributed along the axial direction at alternating intervals, with the minimum clearance d between each rotor blade 234 and the stator blades 244 of the adjacent stage. 1min =0.5~5mm, while ensuring the impact and backflow effect of the blade on the slurry, the mechanical shearing damage of the blade on the slurry is minimized as much as possible, ensuring the particle size integrity of the material and ensuring the performance of the material.

[0042] In this embodiment, the dispersion component of the dispersion device 2 disperses the slurry by impacting it with radially extending blades. The blades are inclined downwards, and the inclination direction of the stator blades 244 is opposite to that of the rotor blades 234. On the one hand, after the slurry accelerates into the dispersion chamber 211, it will repeatedly impact several stages of blades, generating repeated backflow. The slurry is fully dispersed through repeated impact and backflow. On the other hand, since the inclination directions of the stator blades 244 and the rotor blades 234 are opposite, the space between the stator blades 244 and the adjacent stage rotor blades 234 is larger, which reduces the mechanical shearing effect of the blades on the slurry, reduces the mechanical shearing damage of the slurry, ensures the particle size integrity of the material, and ensures the performance of the material. Furthermore, since the mechanical shearing effect of the blades on the slurry is less, the temperature rise of the slurry is slower, which helps to reduce energy consumption.

[0043] The dispersion device 2 in this embodiment is suitable for the preparation of slurries of high-nickel ternary materials, silicon-carbon anode materials, etc., which have large particle size and small specific surface area.

[0044] The third embodiment of the dispersing device 2 is described in detail below. Figures 9 to 12 As shown.

[0045] Unlike the two embodiments described above, the dispersion device 2 in this embodiment uses a dispersion component with a different structure, which includes a dispersion rotor 23 and a dispersion stator 24.

[0046] The dispersing rotor 23 includes a rotor base plate 231, a rotor dispersing ring 232, and a sleeve 233. The rotor base plate 231 is radially arranged, the rotor dispersing ring 232 is arranged on the radially outer side of the rotor base plate 231, and the sleeve 233 is arranged on the radially inner side of the rotor base plate 231. The sleeve 233 is sleeved on the main shaft 22. The rotor dispersing ring 232 has a radially through rotor flow hole 2321. On the outer circumferential surface of the rotor dispersing ring 232, there are several radially outwardly protruding ridges 235 and several radially inwardly concave valleys 236 evenly arranged along the circumferential direction. The ridges 235 and valleys 236 are alternately distributed, and the rotor flow hole 2321 is opened on the valley 236. The ridges 235 and valleys 236 extend along the entire axial length of the rotor dispersing ring 232. The ridges 235 have an arc-shaped convex surface, and the valleys 236 have an arc-shaped concave surface.

[0047] The dispersion stator 24 is a cylindrical component fixed to the housing assembly 21. The inner circumferential surface of the dispersion stator 24 is uniformly provided with a plurality of radially inwardly protruding inner ridges 245 and a plurality of radially outwardly concave inner valleys 246, spaced alternately. The inner ridges 245 and inner valleys 246 extend along the entire axial length of the dispersion stator 24. The inner ridges 245 have an arc-shaped inner convex surface, and the inner valleys 246 have an arc-shaped outer concave surface.

[0048] The distributed stator 24 is sleeved on the outer periphery of the rotor distributed ring 232 of the distributed rotor 23, and the minimum distance d between the outer convex rib 235 of the rotor distributed ring 232 and the inner convex rib 245 of the distributed stator 24 is... 2min =0.5~5mm, which is beneficial to improve local extrusion pressure and kneading and dispersing ability. While promoting dispersion, it also avoids excessive temperature rise and resistance.

[0049] In this embodiment, the dispersion component of the dispersion device 2 disperses the slurry through alternating concave and convex kneading. After the slurry enters the dispersion chamber 211, it enters the area between the dispersion stator 24 and the rotor dispersion ring 232 through the rotor flow hole 2321 of the rotor dispersion ring 232 under the action of centrifugal force. When the slurry flows through the convex surface of the dispersion stator 24 and / or the rotor dispersion ring 232, it is subjected to increased compression, and when it flows through the concave surface of the dispersion stator 24 and / or the rotor dispersion ring 232, the pressure is released, thereby achieving repeated kneading of the slurry. Under the repeated kneading action, the slurry is uniformly dispersed. The dispersion component of this embodiment performs kneading dispersion of the slurry through the alternating action of concave and convex surfaces, resulting in more concentrated high-shear dispersion energy, higher dispersion uniformity, and higher dispersion efficiency.

[0050] The dispersion device 2 in this embodiment is suitable for the preparation of slurries with high / ultra-high solids content.

[0051] The pulp preparation using the circulating pulping system described in this invention mainly includes the following steps: Step 1: Add liquid material. Add a certain amount of solution to the circulation tank device 1.

[0052] Start the inlet pump 7 of the inlet pipeline 300 and open the control valve 8 on the inlet branch pipe 301 connected to the liquid inlet 112. The solution in the liquid tank 4 is quantitatively added to the circulation tank device 1 through the inlet pipeline 300 and the liquid inlet 112. The solution added to the circulation tank device 1 is a liquid of multiple different media added in different batches. Each batch is a single-media solution. The various media solutions are not mixed before addition. The medium X solution with the lowest viscosity and / or the largest total amount is added in batches. The total amount of medium X solution required is b (kg). When the liquid is started, the solution added in the start-up stage is a (kg). The ratio of the solution added a to the total amount b is 1>a / b≥0.7. The remaining solution (total solution - solution added in the start-up stage) is reserved in the liquid tank 4 for subsequent spraying steps into the circulation tank device 1. After the solution is filled to the required level during the start-up phase, the inlet pump 7 and the control valve 8 on the corresponding inlet manifold 301 are turned off to stop the liquid filling. In this step, the volume of the solution added to the circulation tank 11 accounts for about 30% of the volume of the circulation tank 11, leaving about 70% of the space inside the circulation tank 11.

[0053] The amount of solution added during the start-up phase ensures that the solution in the circulating tank device 1 has sufficient liquid level and fluidity, laying the foundation for the subsequent formation of a stable solution vortex and the rapid wetting of powder.

[0054] Step 2: Disperse and circulate the injected solution.

[0055] Start the stirring mechanism 12 and the dispersing mechanism 13 of the circulation tank device 1, and then start the dispersing device 2 and the circulation pump 5 on the circulation pipeline 100. The solution in the circulation tank device 1 circulates through the circulation pipeline 100 until a stable solution vortex is formed in the circulation tank 11.

[0056] Under the power of the circulating pump 5 and the assistance of the stirring mechanism 12 and the dispersing mechanism 13, a stable solution vortex will be formed in the circulating tank 11. The centrifugal force and shear force generated by the vortex can provide power for the rapid wetting and dispersion of the powder, so that the various powders put in can be quickly wrapped and wetted by the solution, effectively reducing the occurrence of powder agglomeration and improving the initial mixing effect of powder and solution.

[0057] Step 3: Add powder to the circulating tank device 1.

[0058] The metered powder is fed into the powder tank device 3, and the mixing motor 33 is started to drive the mixing mechanism 32 to mix the powder fed into the powder tank 31. After the powder is mixed, the quantitative feeding device 34 is started to gradually and evenly add the powder in the powder tank 31 into the solution vortex in the circulation tank device 1. Since about 70% of the space volume is still left inside the circulation tank 11, the large space volume can avoid the accumulation and blockage of powder when it is added, so that the powder can dissolve into the solution and quickly wet the solution. In this step, the powder is added gradually until the total amount of solution and powder in the circulation tank 11 accounts for about 80% of the volume of the circulation tank 11.

[0059] Step 4: Spray the remaining solution into the circulation tank device 1.

[0060] Start the inlet pump 7 of the inlet pipeline 300 and open the control valve 8 on the inlet branch pipe 301 connected to the spray device 14. The remaining solution in the liquid tank 4 is sprayed into the circulation tank device 1 through the inlet pipeline 300 and the spray device 14. Under the high-pressure jet action of the spray device 14, the solution forms a uniform spray mist, which thoroughly washes the tank wall, tank top, and air in the cavity above the liquid surface of the circulation tank 11. This washes away all the powder adhering to the tank wall and tank top, as well as the powder particles suspended in the air, into the slurry in the circulation tank 11, so that the powder is fully recycled and utilized, avoiding powder waste, improving the effective utilization rate of powder, ensuring the mixing effect of the slurry, and improving the precision and quality of the slurry. To improve the washing effect, depending on the floating of the powder, the remaining solution in the liquid tank 4 can be sprayed into the circulation tank 11 in several times (e.g., 1-3 times). The remaining solution volume in liquid tank 4 is c (kg), a+c=b, and the total liquid inflow is precisely controlled according to the solid-liquid ratio requirements of the slurry.

[0061] In steps two through four, the stirring mechanism 12, the dispersing mechanism 13, the dispersing device 2, and the circulating pump 5 of the circulating tank device 1 are always kept on. The dispersing speed of the dispersing mechanism 13 is at a medium-low speed, with a linear velocity of about 8 to 15 m / s. The dispersing speed of the dispersing device 2 is at a medium-high speed, with a linear velocity of 15 to 35 m / s.

[0062] Step 5: High-speed circulation to complete pulping.

[0063] After the remaining solution in liquid tank 4 is sprayed, the inlet pump 7 and the control valve 8 on the corresponding inlet pipe 301 are turned off. The stirring mechanism 12, the dispersing mechanism 13, the dispersing device 2, and the circulating pump 5 of the circulating tank device 1 remain on. The dispersing speed of the dispersing mechanism 13 is adjusted to medium-high speed, with a linear velocity of approximately 15-30 m / s. The dispersing speed of the dispersing device 2 is maintained at medium-high speed, with a linear velocity of 15-35 m / s. The slurry is continuously circulated and dispersed at high speed until the slurry preparation is completed, resulting in the finished slurry. The dispersing mechanism 13 and the dispersing device 2, through the shearing force and impact force generated by the high-speed circulation, as well as the stirring and dispersing action of the stirring mechanism 12 and the dispersing mechanism 13, further disperse the powder particles in the slurry evenly, eliminate residual powder agglomerates, and ensure that the powder and solution components are fully integrated, ultimately obtaining a finished slurry with qualified quality, uniform dispersion, and meeting the precision requirements.

[0064] A specific example of pulping using the circulating pulping system described in this invention: (1) Add 35 kg of deionized water (solution) from liquid tank 4 to circulation tank device 1. The total amount of solution is 70% of the total solution. The total amount of solution is 50 kg. The remaining amount of solution in liquid tank 4 is 15 kg.

[0065] (2) Start the stirring mechanism 12 and the dispersing mechanism 13 (rotation speed of 10m / s), the circulating pump 5 (flow rate of 8m³ / h), and the dispersing device 2 (shearing speed of 25m / s) of the circulating tank device 1, and heat them at a constant temperature of 45℃ to form a stable circulating flow field.

[0066] (3) Slowly add 1.2 kg of CMC (sodium carboxymethyl cellulose) powder to the circulating tank device 1 and stir for 30 min until it is initially dissolved; then add 0.3 kg of SA (sodium alginate) powder in two batches (0.15 kg each time) with an interval of 15 min each time, and continue stirring for 60 min to make the CMC powder and SA powder fully mixed to form a synergistic thickening network.

[0067] (4) Add 0.2 kg of PEG-2000 (polyethylene glycol-2000) to the circulating tank device 1 and stir continuously for 10 min to reduce the interfacial tension between solid and liquid.

[0068] (5) Keep the rotation speed of the stirring mechanism 12 and the dispersing mechanism 13 in the circulating tank device 1 at 10 m / s, the rotation speed of the dispersing device 2 at 25 m / s, and adjust the flow rate of the circulating pump 5 to 18 m³ / h so that the thickener solution forms a strong shear vortex.

[0069] (6) Add 0.8 kg of Super P (conductive carbon black) to the circulating tank device 1 and stir continuously for 10 min; then slowly inject 0.4 kg of CNT (carbon nanotubes) into the center of the vortex and stir continuously for 15 min.

[0070] (7) 95.0 kg of silicon-carbon composite material is fed into the powder tank device 3 and added to the vortex center of the circulating tank device 1 in three batches through the sealed quantitative feeding device 34, with an interval of 15 min between each batch and the feeding speed controlled at 3 kg / min.

[0071] (8) Adjust the stirring speed of the stirring mechanism 12 and the dispersing mechanism 13 of the circulating tank device 1 to 15 m / s, increase the flow rate of the circulating pump 5 to 25 m³ / h, and the shearing speed of the dispersing device 2 to 25 m / s. Stir continuously for 60 min at 25°C.

[0072] (9) Turn on the spray system for the remaining solution and spray the remaining 15 kg of deionized water in the liquid tank 4 into the circulating tank device 1 through several spray devices 14. The shear speed of the dispersion device 2 is 25 m / s. The deionized water is sprayed three times through the spray devices 14, with an interval of 5 min between the two sprays: First time: Add 5kg of deionized water, spray the tank wall and top of the circulating tank 11 under high pressure to rinse the floating powder, and stir the stirring mechanism 12 and the dispersing mechanism 13 at a stirring speed of 15m / s for 5 minutes. Second step: Add 5kg of deionized water and spray it on all inlet and outlet ports and pipe joints of the circulating tank 11 to avoid powder residue, for 5 minutes. Third step: Add 5 kg of deionized water and spray it thoroughly over the suspended particles above the liquid surface for 5 minutes.

[0073] (10) Keep the circulating pump 5 (flow rate 22 m³ / h), the stirring mechanism 12 and the dispersing mechanism 13 (speed 18 m / s) running, increase the shear speed of the dispersing device 2 to 30 m / s, first slowly add 1.5 kg of SBR (styrene-butadiene rubber) emulsion, shear and stir for 15 min; then inject 0.8 kg of PI (polyimide) solution through the metering pump, and continue stirring for 30 min to obtain a finished slurry with qualified quality, uniform dispersion and high precision.

[0074] The above description is an explanation of the present invention and not a limitation thereof. The present invention can be modified in any form without departing from its spirit.

Claims

1. A circulating pulping system, comprising a circulating tank device (1), a dispersing device (2), a powder tank device (3), and a liquid tank (4); characterized in that: The dispersing device (2) is connected to the circulating tank device (1) through the circulating pipeline (100), the powder tank device (3) is connected to the circulating tank device (1) through the powder inlet pipeline (200), and the liquid tank (4) is connected to the circulating tank device (1) through the liquid inlet pipeline (300). The circulating tank device (1) is provided with several liquid inlets (112) and several spray nozzles (116). The liquid inlets (112) and several spray nozzles (116) are respectively connected to the liquid inlet pipeline (300) through the liquid inlet branch pipe (301). The liquid inlet (112) is connected to the inner cavity of the circulating tank device (1). The spray nozzle (116) is equipped with a spray device (14). During pulping, the solution in the liquid tank (4) is injected into the circulating tank device (1) in batches. The solution is injected into the circulating tank device (1) once through the liquid inlet (112) and / or the spray device (14).

2. The circulating pulping system according to claim 1, characterized in that: The spray device (14) can be adjusted by lifting and / or rotating.

3. The circulating pulping system according to claim 1, characterized in that: The dispersing device (2) is provided with a dispersing assembly, which includes a dispersing rotor (23) and a dispersing stator (24). The dispersing rotor (23) is sleeved on the main shaft (22), and the dispersing stator (24) is fixed on the housing assembly (21). Dispersion rings are provided on the dispersion rotor (23) and dispersion stator (24), and several flow holes are provided on the dispersion rings; Alternatively, several blades are provided on the dispersed rotor (23) and dispersed stator (24), and the blades are divided into several levels, with several blades in each level. The blades of the several levels are distributed from top to bottom along the axial direction. The rotor blades (234) and stator blades (244) are inclined downwards, and the inclination direction of the stator blades (244) is opposite to the inclination direction of the rotor blades (234). Alternatively, the dispersed rotor (23) is provided with several external convex ridges (235) and external concave valleys (236) along the circumferential direction, with the external convex ridges (235) and external concave valleys (236) interspersed one after another, and the dispersed stator (24) is provided with several internal convex ridges (245) and internal concave valleys (246) along the circumferential direction, with the internal convex ridges (245) and internal concave valleys (246) interspersed one after another; there is a gap between the external convex ridges (235) of the dispersed rotor (23) and the internal convex ridges (245) of the dispersed stator (24); and several rotor flow holes (2321) are opened on the dispersed rotor (23).

4. The circulating pulping system according to claim 1, characterized in that: A guide plate (26) is provided inside the slurry inlet (213) of the dispersion device (2). The guide plate (26) is sleeved on the main shaft (22). Several guide blades (262) are provided on the guide plate (26). The ratio of the flow channel area S1 formed between the guide plate (26) and the side wall of the slurry inlet (213) to the flow channel area S2 of the slurry inlet (213) is: 0.6≤S1 / S2<1.

0.

5. The circulating pulping system according to claim 1, characterized in that: The circulating tank device (1) has a stirring mechanism (12) and a dispersing mechanism (13) vertically arranged inside the circulating tank body (11), and a cooling jacket (115) is provided on the wall of the circulating tank body (11); the powder tank device (3) is provided with a mixing mechanism (32) and a quantitative feeding device (34).

6. The circulating pulping system according to claim 1, characterized in that: A circulation pump (5) and a cooling device (6) are installed on the circulation pipeline (100); an inlet pump (7) is installed on the liquid inlet pipeline (300); and control valves (8) are installed on the circulation pipeline (100) and the powder inlet pipeline (200).

7. A pulping method using the circulating pulping system of claim 1, characterized in that: include, Step 1: Add a certain amount of solution into the circulation tank device (1); Step 2: Disperse and circulate the injected solution; Step 3: Add powder to the circulating tank device (1); Step 4: Spray the remaining solution into the circulation tank device (1); Step 5: High-speed circulation to complete pulping.

8. The pulping method according to claim 7, characterized in that: In step one, the ratio of the amount of solution added (a) to the total amount of solution required (b) is 1 > a / b ≥ 0.

7. In step four, the remaining amount of solution sprayed is c, and a + c = b.

9. The pulping method according to claim 7, characterized in that: The remaining solution in step four is sprayed into the circulating tank (11) in several times, with a certain time interval between the two sprays.

10. The pulping method according to claim 7, characterized in that: In step one, the volume of the solution added to the circulation tank (11) accounts for 30% of the volume of the circulation tank (11); in step three, the total volume of the powder added to the solution and the powder accounts for 80% of the volume of the circulation tank (11).

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