Integrated equipment suitable for ionic liquid fiber pulping and swelling and process thereof

Abstract

The invention discloses integrated equipment suitable for ionic liquid fiber pulping and swelling and a process thereof, and relates to the field of ionic liquid fiber production. According to the invention, the advantages of dry-method pulping and wet-method pulping are fused, i.e., pulp and ionic liquid are contacted in the repulping barrel and then are stirred, and the pulp is crushed and swelled while being stirred, so that the two procedures of pulp crushing and swelling are simultaneously completed through one device, the input-output ratio of the device is greatly improved, the device investment is saved, and the production efficiency is improved. And the advantages of wet-method pulping and dry-method pulping are considered, so that a large amount of dust and explosion danger are prevented from being generated when the pulp is crushed, and the technological process is greatly shortened. Meanwhile, the crushing rotor of a pagoda-shaped structure rotates at a high speed and is matched with the impact plate for increasing the stirring friction force and the sawtooth surface of the turntable, so that the crushing effect of the pulp can be remarkably improved, sufficient swelling of the ionic liquid in the pulp is ensured, sufficient dissolution of the pulp is facilitated, and the quality of the spinning solution is further improved. In addition, the method has the advantage of reducing the cost.

Description

Technical Field

[0001] This invention relates to the technical field of ionic liquid fiber production, specifically to an integrated equipment and process for pulping and swelling ionic liquid fibers. Background Technology

[0002] Ion-liquid fiber is an abbreviation for regenerated ionic liquid cellulose fiber, a type of chemical fiber. Ion-liquid fiber belongs to regenerated cellulose fiber. It is made from natural cellulose as raw material, through physical methods to dissolve the natural cellulose into a spinnable solution, which is then used to generate cellulose fibers via a spinning machine. Compared to traditional petroleum-based synthetic fibers, ionic liquid fiber is a hydrophilic fiber, possessing the advantage of good affinity with human skin and being the closest to cotton in properties among all chemical fibers. Because the raw materials for ionic liquid fiber are natural cellulose—including wood, bamboo, hemp, and cotton linters—it is biodegradable after disposal, making it an environmentally friendly chemical fiber.

[0003] The main process flow for producing ionic liquid fibers generally consists of two steps: the first step is the dosing process—converting cellulose into a solution suitable for spinning; the second step is the spinning process—converting the spinning dosing into finished fibers. The dosing process typically involves: pulp crushing → swelling → dissolving → filtration → degassing → spinning dosing. Currently, pulp crushing mainly involves two processes: dry crushing and wet crushing. Dry crushing uses mechanical methods to crush rolls or bags of pulp into pulp flakes approximately 10mm in diameter before proceeding to the swelling step with the ionic liquid. Wet crushing uses a hydraulverizer, common in paper and viscose industries, where a rotor drives water flow to crush bags of pulp. After crushing, mechanical pressing is used to reduce the moisture content of the pulp to below 50% before proceeding to the swelling step with the ionic liquid. The dry and wet pulverization processes mentioned above each have their advantages and disadvantages: the dry pulverization process has a short process flow and requires less equipment investment, but dust is generated during the pulverization process, and there is a risk of explosion if not handled properly; the wet pulverization process is mature, but the process flow is long and the equipment investment is large. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of the existing technology by providing an integrated device and process for ionic liquid fiber pulping and swelling. This invention not only allows for the simultaneous completion of pulping and swelling processes in a single device, significantly improving the input-output ratio and saving on equipment investment, but also combines the advantages of both wet and dry pulping. It avoids the large amounts of dust and explosion hazards generated during pulping, greatly shortens the process flow, and significantly improves the pulping effect, ensures sufficient swelling of the ionic liquid within the pulp, and facilitates complete dissolution of the pulp, thereby improving the quality of the spinning solution. Furthermore, this invention also has the advantage of cost reduction.

[0005] The objective of this invention can be achieved through the following technical measures: This invention provides an integrated device for ionic liquid fiber pulping and swelling, comprising, arranged sequentially from top to bottom according to the material flow direction, a weighing and conveying system, a pulping tank, a crushing rotor, a discharge valve, a high-consistency pump (the weighing and conveying system is used to weigh the mass of each batch of pulp to be added and to convey the weighed pulp to the feed inlet at the top of the pulping tank for feeding. The pulping tank serves not only to hold the ionic liquid but also to provide installation space for the crushing rotor, and also as a stirring space, pulping, and swelling space. The crushing rotor rotates at high speed to crush the pulp. The discharge valve controls the opening and closing of the discharge port, opening when discharge is needed and closing at other times. The high-consistency pump is used to transport the swollen pulp to subsequent work stations), and a rotor drive system (providing rotational power to the crushing rotor); wherein, the crushing rotor is installed in the lower part of the inner cavity of the pulping tank, and the two are arranged coaxially (for balanced force); the crushing rotor is driven by a rotor... The structure comprises a pagoda-shaped structure consisting of a shaft, several propeller blades fixed to the surface of the shaft, and a rotating disk encircling the bottom of the shaft. The shaft rotates at high speed under the drive of the rotor transmission system, causing the propeller blades and rotating disk to rotate synchronously. The ionic liquid near the propeller blades and rotating disk, along with the pulp encased in the ionic liquid, rotates together under centrifugal force. During rotation, the pulp is gradually pulverized by impacts from the high-speed rotating propeller blades, the walls of the pulping tank and the impact plates fixed to the tank walls, and the serrated surface of the rotating disk. Therefore, the high-speed rotation of the pagoda-shaped pulverizing rotor, combined with the impact plates and the serrated surface of the rotating disk that increase stirring friction, significantly improves the pulp pulverization effect, ensures sufficient swelling of the ionic liquid within the pulp, facilitates complete dissolution of the pulp, and thus greatly improves the quality of the spinning solution. The shaft extends downwards from the bottom of the rotating disk, processed into a tapered shaft section, and is connected to the transmission shaft driven by the rotor transmission system.

[0006] In this invention, several impact plates are fixed on the wall of the pulping tank to increase the stirring friction; the upper surface of the turntable is a serrated surface (both the impact plates and the serrated surface can increase the stirring friction, and when combined with the pagoda-shaped crushing rotor to rotate at high speed, it can significantly improve the crushing effect of the pulp, ensure that the ionic liquid swells fully in the pulp, facilitate the full dissolution of the pulp, and thus improve the quality of the spinning solution).

[0007] The high-concentration conveying pump described in this invention is a screw-type conveying pump (capable of conveying high-concentration porridge).

[0008] The rotor transmission system described in this invention is composed of either a drive motor or a V-belt or a reducer (which can be selected according to the power transmitted, and has the advantage of reducing costs).

[0009] The discharge valve described in this invention is either a ball valve or a gate valve (which can be flexibly selected as needed, and has the advantages of flexible use and easy maintenance).

[0010] The steps of an integrated process for ionic liquid fiber pulping and swelling according to the present invention are as follows: A. Calculate the ingredients: Calculate the required mass of ionic liquid based on the desired mass concentration of the porridge to be produced and the mass of pulp to be added for each batch of porridge; B. Injecting ionic liquid: Add the required mass of ionic liquid calculated in step A into the inner cavity of the pulping tank. C. Start the crushing rotor: Turn on the crushing rotor drive system to drive the crushing rotor to rotate; D. Weighing and feeding pulp: Start the weighing and conveying system, automatically weigh the mass of each batch of pulp to be added in step A, and then convey it to the top feed inlet of the pulping tank for feeding. E. Crushing and swelling: The crushing rotor rotates at high speed to crush the pulp fed into the inner cavity of the pulping tank; at the same time, the ionic liquid penetrates evenly into the pulp, completing the pulp swelling process simultaneously. F. Discharge: After pulping and swelling are completed, the high-concentration conveying pump and discharge valve are opened in sequence to transport the swollen pulp to the subsequent work station.

[0011] The mass concentration of the porridge produced in this invention is 8-15%.

[0012] The mass range of each batch of pulp to be added in this invention is 100-3000 kg.

[0013] The rotational speed of the crushing rotor described in this invention is 100 to 300 rpm.

[0014] The total volume of the pulping tank body described in this invention is 2.5 to 40 cubic meters.

[0015] The design principle of this invention is as follows: This invention combines the advantages of dry and wet pulping processes—namely, contacting the pulp with the ionic liquid within the pulping tank before stirring, simultaneously crushing and swelling. This allows for the simultaneous completion of pulp crushing and swelling in a single unit, significantly improving the equipment's return on investment and saving on equipment costs. Furthermore, it combines the advantages of both wet and dry pulping, avoiding the large amounts of dust and explosion hazards generated during pulp crushing, and greatly shortening the process flow. Simultaneously, the high-speed rotation of the pagoda-shaped crushing rotor, combined with the impact plates and serrated surfaces of the turntable to increase stirring friction, significantly enhances the pulp crushing effect, ensures sufficient swelling of the ionic liquid within the pulp, and facilitates complete dissolution of the pulp, thereby improving the quality of the spinning solution. In addition, this invention allows for the selection of either a V-belt or a reducer for power transmission, depending on the required power, thus reducing costs.

[0016] The beneficial technical effects of the present invention are as follows: This invention enables the simultaneous completion of pulp crushing and swelling processes with a single device, significantly improving the equipment's input-output ratio and saving on investment. It also combines the advantages of both wet and dry pulping processes, avoiding the large amounts of dust and explosion hazards generated during pulp crushing, greatly shortening the process flow, and significantly improving pulp crushing efficiency, ensuring sufficient swelling of the ionic liquid within the pulp, and facilitating complete pulp dissolution, thereby enhancing the quality of the spinning solution. Furthermore, this invention also offers the advantage of cost reduction. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the layout of the integrated ionic liquid fiber pulping and swelling equipment in this invention.

[0018] Figure 2 This is a schematic diagram of the crushing rotor.

[0019] The parts numbered in the diagram are as follows: 1. Weighing and conveying system; 2. Pulping tank body; 2-1. Impact plate; 3. Crushing rotor; 3-1. Shaft; 3-1-1. Conical shaft section; 3-2. Propeller blade; 3-3. Turntable; 4. Rotor drive system; 5. Discharge valve; 6. High-concentration conveying pump. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments: like Figure 1 , Figure 2As shown, an integrated device for ionic liquid fiber pulping and swelling according to the present invention includes a weighing and conveying system 1, a pulping tank body 2, a crushing rotor 3, a discharge valve 5, a high-consistency conveying pump 6 (the weighing and conveying system 1 is used to weigh the mass of each batch of pulp to be added and to convey the weighed pulp to the top inlet of the pulping tank body 2 for feeding. The pulping tank body 2 is used to hold the ionic liquid, provide installation space for the crushing rotor 3, and also serve as a stirring space, pulping and swelling space. The crushing rotor 3 rotates at high speed to crush the pulp. The discharge valve 5 is used to control the opening and closing of the discharge port, opening when discharge is needed and closing at other times. The high-consistency conveying pump 6 is used to transport the swollen pulp to the subsequent work station), and a rotor transmission system 4 (to provide rotational power for the crushing rotor 3); wherein, the crushing rotor 3 is installed in the lower part of the inner cavity of the pulping tank body 2, and the two are arranged coaxially (with balanced force); the crushing rotor 3 is fixed to the rotating shaft 3-1. The pagoda-shaped structure consists of several spiral blades 3-2 and a rotating disk 3-3 ringed at the bottom of the shaft. The shaft 3-1 rotates at high speed under the drive of the rotor transmission system 4, causing the spiral blades 3-2 and the rotating disk 3-3 to rotate synchronously. The ionic liquid near the spiral blades 3-2 and the rotating disk 3-3, and the pulp encased in the ionic liquid, rotate together under centrifugal force. During rotation, the pulp is impacted by the high-speed rotating spiral blades 3-2, the wall of the pulping tank 2, and objects fixed to the tank wall. After being impacted by the plate 2-1 and the serrated surface of the turntable 3-3, the pulp is gradually crushed. Therefore, the high-speed rotation of the pagoda-shaped crushing rotor, combined with the impact plate and the serrated surface of the turntable which increase the stirring friction, can significantly improve the crushing effect of the pulp, ensure that the ionic liquid swells fully in the pulp, facilitate the full dissolution of the pulp, and thus improve the quality of the spinning solution. The shaft 3-1 extends downward from the bottom end of the turntable and is processed into a tapered shaft section 3-1-1, which is connected to the drive shaft driven by the rotor transmission system 4.

[0021] In this invention, several impact plates 2-1 are fixed on the wall of the pulping tank 2 to increase the stirring friction; the upper surface of the turntable 3-3 is a serrated surface (both the impact plates 2-1 and the serrated surface can increase the stirring friction, and when combined with the pagoda-shaped crushing rotor 3 to rotate at high speed, it can significantly improve the crushing effect of pulp, ensure that the ionic liquid swells fully in the pulp, facilitate the full dissolution of pulp, and thus improve the quality of spinning solution).

[0022] The high-concentration conveying pump 6 described in this invention is a screw-type conveying pump (capable of conveying high-concentration porridge). Example 1

[0023] The steps of an integrated process for ionic liquid fiber pulping and swelling in Example 1 are as follows: A. Calculate the ingredients: Based on the required mass concentration of the porridge to be produced being 8%, and considering the mass of pulp to be added to each batch of porridge being 100Kg, the corresponding mass of ionic liquid required is calculated to be 1150Kg. B. Injecting ionic liquid: Add 1150 kg of ionic liquid into the inner cavity of the pulping tank 2 with a total volume of 2.5 cubic meters; C. Start the crushing rotor: Turn on the crushing rotor transmission system 4, which is composed of a drive motor and a V-belt, and select the speed of the crushing rotor 3 as 300 rpm to drive the crushing rotor 3 to rotate. D. Weighing and feeding pulp: Start the weighing and conveying system 1, automatically weigh the mass of each batch of pulp to be added in step A, and then convey it to the top feed port of the pulping tank 2 for feeding. E. Crushing and swelling: The crushing rotor 3 rotates at high speed to crush the pulp fed into the inner cavity of the pulping tank; at the same time, the ionic liquid penetrates evenly into the pulp, and the pulp swelling process is completed simultaneously. F. Discharge: After pulping and swelling are completed, the high-concentration conveying pump 6 and the ball valve discharge valve 5 are opened in sequence to transport the swollen pulp to the subsequent work station. Example 2

[0024] The steps of an integrated process for ionic liquid fiber pulping and swelling in Example 2 are as follows: A. Calculate the ingredients: Based on the required mass concentration of the porridge to be produced being 15%, and considering the mass of pulp to be added to each batch of porridge being 3000 kg, the corresponding mass of ionic liquid required is calculated to be 17000 kg. B. Injecting ionic liquid: Add 17,000 kg of ionic liquid into the inner cavity of the pulping tank 2 with a total volume of 40 cubic meters. C. Start the crushing rotor: Turn on the crushing rotor transmission system 4, which is composed of a drive motor and a reducer, and select the speed of the crushing rotor 3 as 100 rpm to drive the crushing rotor 3 to rotate. D. Weighing and feeding pulp: Start the weighing and conveying system 1, automatically weigh the mass of each batch of pulp to be added in step A, and then convey it to the top feed port of the pulping tank 2 for feeding. E. Crushing and swelling: The crushing rotor 3 rotates at high speed to crush the pulp fed into the inner cavity of the pulping tank; at the same time, the ionic liquid penetrates evenly into the pulp, and the pulp swelling process is completed simultaneously. F. Discharge: After pulping and swelling are completed, the high-concentration conveying pump 6 and the discharge valve 5 with gate valve structure are opened in sequence to transport the swollen pulp to the subsequent work station. Example 3

[0025] The steps of an integrated process for ionic liquid fiber pulping and swelling in Example 3 are as follows: A. Calculate the ingredients: Based on the required mass concentration of the porridge to be produced being 12%, and considering the mass of pulp to be added to each batch of porridge being 1500Kg, the corresponding mass of ionic liquid required is calculated to be 11000Kg. B. Injecting ionic liquid: Add 11,000 kg of ionic liquid into the inner cavity of the pulping tank 2 with a total volume of 26 cubic meters. C. Start the crushing rotor: Turn on the crushing rotor transmission system 4, which is composed of a drive motor and a reducer, and select the speed of the crushing rotor 3 as 200 rpm to drive the crushing rotor 3 to rotate. D. Weighing and feeding pulp: Start the weighing and conveying system 1, automatically weigh the mass of each batch of pulp to be added in step A, and then convey it to the top feed port of the pulping tank 2 for feeding. E. Crushing and swelling: The crushing rotor 3 rotates at high speed to crush the pulp fed into the inner cavity of the pulping tank; at the same time, the ionic liquid penetrates evenly into the pulp, and the pulp swelling process is completed simultaneously. F. Discharge: After pulping and swelling are completed, the high-concentration conveying pump 6 and the ball valve discharge valve 5 are opened in sequence to transport the swollen pulp to the subsequent work station.

Claims

1. An integrated device suitable for ionic liquid fiber pulping and swelling, characterized in that: The integrated equipment includes a weighing and conveying system (1), a pulping barrel body (2), a crushing rotor (3), a discharge valve (5), a high-concentration conveying pump (6), and a rotor transmission system (4) arranged sequentially from top to bottom according to the material flow direction; wherein, the crushing rotor (3) is installed in the lower part of the inner cavity of the pulping barrel body (2), and the two are arranged coaxially; the crushing rotor (3) is a pagoda-shaped structure composed of a rotating shaft (3-1), several spiral blades (3-2) fixed on the surface of the rotating shaft, and a turntable (3-3) ringed around the bottom of the rotating shaft. The rotating shaft (3-1) extends downward to the bottom end of the turntable and is processed into a tapered shaft section (3-1-1), and is connected and used with the transmission shaft driven by the rotor transmission system (4).

2. The integrated equipment for ionic liquid fiber pulping and swelling according to claim 1, characterized in that: Several impact plates (2-1) are fixed on the wall of the pulping barrel (2) to increase the stirring friction; the upper surface of the turntable (3-3) is a serrated surface.

3. The integrated equipment for ionic liquid fiber pulping and swelling according to claim 1, characterized in that: The high-concentration transfer pump (6) is a screw-type transfer pump.

4. The integrated equipment for ionic liquid fiber pulping and swelling according to claim 1, characterized in that: The rotor transmission system (4) is composed of either a drive motor or a V-belt or a reducer.

5. The integrated equipment for ionic liquid fiber pulping and swelling according to claim 1, characterized in that: The discharge valve (5) is either a ball valve or a gate valve.

6. An integrated process for pulping and swelling ionic liquid fibers using the equipment of claim 1, characterized in that: The process steps are as follows: A. Calculate the ingredients: Calculate the required mass of ionic liquid based on the desired mass concentration of the porridge to be produced and the mass of pulp to be added for each batch of porridge; B. Injecting ionic liquid: Add the required mass of ionic liquid calculated in step A into the inner cavity of the pulping tank (2); C. Start the crushing rotor: Turn on the crushing rotor transmission system (4) to drive the crushing rotor (3) to rotate; D. Weighing and feeding pulp: Start the weighing and conveying system (1), automatically weigh the mass of each batch of pulp to be added in step A, and then convey it to the top feed port of the pulping tank (2) for feeding. E. Crushing and swelling: The crushing rotor (3) rotates at high speed to crush the pulp fed into the inner cavity of the pulping tank; at the same time, the ionic liquid penetrates evenly into the pulp and completes the pulp swelling process simultaneously. F. Discharge: After the pulping and swelling are completed, the high-concentration conveying pump (6) and the discharge valve (5) are opened in sequence to transport the swollen pulp to the subsequent work station.

7. The integrated process for pulping and swelling of ionic liquid fibers according to claim 1, characterized in that: The mass concentration of the porridge produced is 8-15%.

8. The integrated process for pulping and swelling of ionic liquid fibers according to claim 1, characterized in that: The mass range of each batch of pulp to be added is 100-3000 kg.

9. The integrated process for ionic liquid fiber pulping and swelling according to claim 1, characterized in that: The rotational speed of the crushing rotor (3) is 100 to 300 rpm.

10. The integrated process for pulping and swelling of ionic liquid fibers according to claim 1, characterized in that: The total volume of the pulping barrel (2) is 2.5 to 40 cubic meters.

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