Pulping raw material impurity removing device and using method

Abstract

The invention discloses a pulping raw material impurity removal device and a use method. The device comprises a gap pressurization area and a separation treatment area, the gap pressurizing area comprises a driving motor and a gap pressurizing device; the separation treatment area comprises an air knife system, a high-pressure water spraying device and a net-shaped conveying belt; the gap pressurizing device comprises a pair of grinding roller bodies, a pair of gap digital display meters and a pair of gap adjusting components. By means of the device, the raw materials can be subjected to the uniform linear pressure effect by accurately controlling application of pressure, and large impurities such as black skin layers on the surfaces of the bast raw materials and cotton seed hulls in fabric are effectively broken. Then the bast raw material or the cotton material subjected to impurity crushing enters a separation treatment area, and black skin of the bast raw material is removed through an air knife and compressed air; and the high-pressure water spraying device can deeply remove dirt and fine impurities in the raw materials, so that the cleanliness and the overall quality of the raw materials are remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of removing impurities from pulping raw materials, and relates to an apparatus and a method for removing impurities from pulping raw materials, specifically to an apparatus and a method for removing large impurities such as the outer epidermis black skin of pulping bast raw materials or cottonseed hulls in cotton materials. Background Art

[0002] Bast raw materials and cotton materials are high-quality papermaking fiber materials. However, compared with raw materials such as wood, bamboo, and grasses, plant barks contain a bark surface layer (i.e., black skin) and an inner bark layer. The bark surface layer in plant barks contains almost no fibers or cellulose. The presence of black skin in the pulp preparation process will consume a large amount of chemicals and is difficult to remove after pulping, which not only leads to a decrease in pulp yield and whiteness, but also results in low pulp cleanliness; large impurities such as cottonseed hulls in cotton materials will also consume a large amount of chemicals during the cooking process. Therefore, in the pulping process of bast or cotton papermaking raw materials, the removal of raw material impurities has a great impact on the subsequent pulping process and pulp quality. In order to achieve the purpose of making full use of plant barks and cotton materials, raw material impurity removal treatment needs to be carried out at the front end of pulp preparation.

[0003] The prior art for removing black skin from bast raw materials basically adopts the following two methods to separate the black skin from the inner bark layer: The first is the manual removal method: for the outer black skin, a tool such as a scraper is used to scrape the surface black skin during stock preparation. The second is the chemical removal method: Chinese Patent Application No. 200910114339.3 discloses a method for quickly separating the mulberry bark surface layer. In this method, the raw materials are first immersed in a raw material immersion solution at 20 - 80°C for 0.5 - 48 hours and then cooked. The chemical auxiliary agent added during cooking is one of soda ash, sodium silicate, or trisodium phosphate. The cooking is carried out at a temperature of 85 - 100°C under normal pressure for 0.5 - 1.5 hours. Finally, a rotary cage washing machine is used for washing, a press for pressing, and a sieve filter for sieving to remove the bark surface impurities. The first method has a large manual labor intensity, low efficiency, and causes more fiber loss in the inner layer of the bast raw materials during the peeling process; the second method uses more chemical raw materials and has a complex operation. Although this method can remove the black skin on the bark surface, it will produce a large amount of waste, resulting in environmental pollution and high production costs. The quality of the obtained inner bark layer is not high and has a degradation effect on the fibers in the inner bark layer.

[0004] The most widely used method for removing impurities in cotton materials is mechanical impurity removal. Common mechanical equipment includes sieves, vibrating screens, air suction dust collectors, etc. Although the mechanical impurity removal method for cotton materials can effectively improve the purity and cleaning efficiency of cotton seeds, there are also some disadvantages that cannot be ignored. For example, after the cotton materials are mechanically decontaminated, although some of the original impurities are removed, large impurities may be broken into many small impurities, fine white stars (cotton knots) and other impurities and defects that are difficult to remove. These small impurities and small defects will consume a large amount of chemicals in the subsequent pulping process.

[0005] At present, separating the outer black skin of the phloem and removing impurities in cotton materials are difficult problems in the field of pulp and paper making. Therefore, there is an urgent need to provide a device for effectively removing impurities in pulping raw materials. Summary of the Invention

[0006] Aiming at the above-mentioned disadvantages and deficiencies of the prior art, the primary object of the present invention is to design and introduce a device for removing impurities in pulping raw materials, which not only realizes the mechanization of the raw material impurity removal operation, but also greatly improves the production efficiency and large-scale production capacity.

[0007] Another object of the present invention is to provide a method for using the above device, which can minimize the damage to the inner layer fibers, thereby retaining the high-quality fiber characteristics of the raw materials.

[0008] In order to achieve the above object, the present invention is realized through the following technical solutions:

[0009] A device for removing impurities in pulping raw materials, characterized in that it includes a gap pressurization area and a separation and treatment area; the gap pressurization area includes a driving motor and a gap pressurization device; the separation and treatment area includes an air knife system, a high-pressure water spraying device, and a mesh conveyor belt;

[0010] The gap pressurization device includes a pair of rolling rollers, a pair of gap digital displays, and a pair of gap adjustment components; the pair of rolling rollers includes an upper roller and a lower roller, the upper roller is a fixed roller, and the lower roller is a movable roller; the gap adjustment component includes a positive and reverse screw, a wedge block, and a fixing plate. The positive and reverse screw passes through the fixing plate in front of the wedge block to keep it horizontal. The tail of the positive and reverse screw is threadedly connected to the wedge block, and the bearing of the lower roller is above the wedge block;

[0011] The outlet of the gap pressurization area is connected to the mesh conveyor belt, and the air knife system and the high-pressure water spraying device are located above the mesh conveyor belt.

[0012] Preferably, the linear pressure between the upper roller and the lower roller ≥ 100 KN / m, the rotational speed of the upper roller is greater than that of the lower roller, and the speed difference between the upper and lower rollers is 4-7%; the roller surface is processed by diagonal knurling, and the knurling modulus is 0.2-0.4 mm.

[0013] Preferably, the gap adjustment range of the gap adjustment member is 0.5 - 25 mm, and the adjustment accuracy is 0.1 mm; the gap digital display is used to measure and display the gap data between the upper and lower rollers.

[0014] Preferably, the drive motor is electrically connected to the rolling roller body, and the motor speed is 5 - 25 m / min.

[0015] Preferably, the air knife system includes an air knife and a gas supply device. The air knife system is close to the outlet of the gap pressurization area. The angle between the air knife and the mesh conveyor belt is 30° - 45°, and the width of the air knife surface is 250 mm; the gas supply device provides a pressure of not less than 0.6 MPa, and the exhaust volume is 1 m 3 / min.

[0016] Preferably, the high-pressure water spraying device is located behind the air knife system. The spraying width is the same as the width of the roller surface, and the water pressure is not less than 10 bar.

[0017] Preferably, the pulping raw material is one or more of Broussonetia papyrifera bark, Morus alba bark, Pteroceltis tatarinowii bark, grade-three cotton, and cotton linter.

[0018] The usage method of the pulping raw material impurity removal device of the present invention is characterized by including the following steps:

[0019] (1) Select the knurling modulus of the upper and lower roller surfaces, set the rotation speeds of the upper and lower rollers, set the pressurization gap, verify the air knife angle and the working parameters of the gas supply device, start the high-pressure water spraying device, and feed the pulping raw material into the gap pressurization area;

[0020] (2) After the treatment is completed, the pulping raw material with impurities removed is obtained at the end of the mesh conveyor belt.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] (1) The present invention first feeds the pulping raw material into the gap pressurization device. By precisely controlling the application of pressure, the raw material is subjected to a uniform linear pressure, which can effectively break the black cortex on the surface of the bast raw material and large impurities such as cottonseed hulls in the fabric.

[0023] (2) After the bast raw material or cotton material with impurities broken enters the separation treatment area, the air knife stripping system removes the black skin of the bast raw material through the air knife and compressed air; the high-pressure water spraying device precisely sprays high-pressure water on the surface of the bast raw material or cotton material, and the powerful water flow impact force deeply removes the dirt and fine impurities in the raw material, significantly improving the cleanliness and overall quality of the raw material.

[0024] (3) The advantages of the present invention lie in its ingenious operation process design, which not only simplifies the operation steps but also greatly improves the processing efficiency and ensures the high quality of raw materials. In addition, the device also has good adaptability and scalability, and is very suitable for application in large-scale industrial production, which helps to improve production efficiency, reduce production costs, and bring significant economic benefits and technological progress to the pulp and paper industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 FIG. is a front view schematic diagram of the device for removing impurities from pulp raw materials of the present invention.

[0026] Figure 2 FIG. is a side view schematic diagram of the device for removing impurities from pulp raw materials of the present invention.

[0027] Figure 3 FIG. is a schematic diagram of the principle of the gap adjustment member of the device for removing impurities from pulp raw materials of the present invention.

[0028] Figure 4 FIG. is a comparison diagram of the effect of removing the outer epidermis black skin of Broussonetia papyrifera raw materials in Example 1.

[0029] Figure 5 FIG. is a comparison diagram of the effect of removing the outer epidermis black skin of Morus alba raw materials in Example 2.

[0030] Figure 6 FIG. is a comparison diagram of the effect of removing the outer epidermis black skin of Pteroceltis tatarinowii raw materials in Example 3.

[0031] Reference numerals: 1 - driving motor; 201 - upper roller; 202 - lower roller; 3 - gap digital display; 4 - gap adjustment member; 401 - handle, 402 - right - hand and left - hand screw rod, 403 - wedge - shaped block, 404 - lower roller bearing, 405 - fixing plate; 5 - mesh conveyor belt; 6 - air knife system; 7 - high - pressure water spraying device. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] The present invention will be further described in detail below with reference to the embodiments, but the embodiments of the present invention are not limited thereto.

[0033] As Figures 1 to 3As shown in the figure, it is a schematic diagram of an impurity removal device for pulping raw materials according to the present invention. The device includes an intermittent pressure zone and a separation and treatment zone; the intermittent pressure zone includes a driving motor 1 and an intermittent pressure device; the separation and treatment zone includes an air knife system 6, a high-pressure water spraying device 7, and a mesh conveyor belt 5; the intermittent pressure device includes a pair of rolling rollers, a pair of gap digital displays 3, and a pair of gap adjusting members 4; the pair of rolling rollers includes an upper roller 201 and a lower roller 202. The upper roller 201 is a fixed roller, and the lower roller 202 is a movable roller; the gap adjusting member includes a right and left threaded screw 402, a wedge block 403, and a fixing plate 405. The right and left threaded screw 402 passes through the fixing plate 405 in front of the wedge block 403 to keep it horizontal. The tail of the right and left threaded screw 402 is threadedly connected to the wedge block 403. Above the wedge block 403 is the bearing 404 of the lower roller; the outlet of the intermittent pressure zone is connected to the mesh conveyor belt 5, and the air knife system 6 and the high-pressure water spraying device 7 are located above the mesh conveyor belt 5.

[0034] The principle of the gap adjusting member of this device for adjusting the gap between the upper and lower rollers is as follows: the upper roller is in a fixed position, and the position of the lower roller can be adjusted up and down; the bearings on both the left and right sides of the lower roller are respectively matched with a pair of gap adjusting members, so that the height can be adjusted separately on both the left and right sides. Combined Figure 3 with the figure, in the gap adjusting member, a handle 401 is provided at the end of the right and left threaded screw. The right-handed thread at one end of the right and left threaded screw is matched with the internal thread of the fixed block, and the left-handed thread at the other end is matched with the internal thread of the wedge block; when the handle is rotated clockwise, the right and left threaded screw drives the wedge block to move forward. Under the push of the inclined surface of the wedge block, the position of the bearing of the lower roller moves upward, reducing the gap between the upper and lower rollers to achieve pressurization; when decompressing, the handle is rotated counterclockwise, the right and left threaded screw drives the inclined surface of the wedge block to move backward, and the lower roller descends under the action of gravity, increasing the gap between the upper and lower rollers to achieve decompression.

[0035] The linear pressure between the upper and lower rollers of the rolling rollers is ≥100 KN / m. The rotational speed of the upper roller is greater than that of the lower roller, and the speed difference between the upper and lower rollers is 4-6%; the roller surface is processed by diagonal knurling, and the knurling modulus is 0.2-0.4 mm. The gap adjustment range of the gap adjusting member is 0.5-25 mm, and the adjustment accuracy is 0.1 mm. The gap digital display 3 is used to measure and display the gap data between the upper and lower rollers. The driving motor 1 is electrically connected to the pair of rolling rollers, and the motor speed is 5-25 m / min.

[0036] The air knife system 6 includes an air knife and a gas supply device. The air knife system is located near the outlet of the intermittent pressure zone. The angle between the air knife and the mesh conveyor belt 5 is 30°-45°, and the width of the air knife surface is 250 mm; the gas supply device provides a pressure of not less than 0.6 MPa, and the exhaust volume is 1 m 3 / min. The high-pressure water spraying device 7 is located behind the air knife system, and the spraying width is the same as the width of the roller surface, and the water pressure is not less than 10 bar.

[0037] The main operation steps of the impurity removal device of the present invention are as follows:

[0038] Step 1: Select the knurling module of the upper and lower roller surfaces

[0039] Step 2: Set the rotational speeds of the upper and lower rollers

[0040] Step 3: Set the pressure gap

[0041] Step 4: Verify the air knife angle and the air supply working parameters

[0042] Step 5: Start the high-pressure water spraying device

[0043] Step 6: Start the device to carry out impurity removal work

[0044] Example 1

[0045] Taking Broussonetia papyrifera bark as the raw material, when the knurling module of this device is set to 0.4 mm, the rotational speed of the lower roller is 20 m / min, and the rotational speed of the upper roller is 21 m / min; the gap between the upper roller and the lower roller is 1.5 mm and the pressure applied by the air knife is 0.6 MPa, and the pressure of the high-pressure water is set to 10 bar, the outer black bark of Broussonetia papyrifera bark is significantly removed under these process parameters.

[0046] Example 2

[0047] Taking Morus alba bark as the raw material, when the knurling module of this device is set to 0.4 mm, the rotational speed of the lower roller is 18 m / min, and the rotational speed of the upper roller is 19 m / min; the gap between the upper roller and the lower roller is 1.2 mm and the pressure applied by the air knife is 0.7 MPa, and the pressure of the high-pressure water is set to 12 bar, the outer black bark of Morus alba bark is significantly removed under these process parameters.

[0048] Example 3

[0049] Taking Pteroceltis tatarinowii bark as the raw material, when the knurling module of this device is set to 0.2 mm, the rotational speed of the lower roller is 20 m / min, and the rotational speed of the upper roller is 21 m / min; the gap between the upper roller and the lower roller is 1.5 mm and the pressure applied by the air knife is 0.6 MPa, and the pressure of the high-pressure water is set to 10 bar, the black bark of Pteroceltis tatarinowii bark is significantly removed under these process parameters.

[0050] Example 4

[0051] Taking tertiary cotton as the raw material, the knurling module of this device is set to 0.2 mm, the rotational speed of the lower roller is 22 m / min, and the rotational speed of the upper roller is 23 m / min; the gap between the upper roller and the lower roller is 1.5 mm. In addition, the pressure applied by the air knife is 0.6 MPa, and the pressure of the high-pressure water is set to 10 bar. Most of the fine impurities in the tertiary cotton and cotton linter raw materials are removed under these process parameters.

[0052] Example 5

[0053] Using cotton linter as raw material, the knurling modulus of the device is set to 0.4 mm, the rotational speed of the lower roller is 20 m / min, and the rotational speed of the upper roller is 21 m / min; the gap between the upper roller and the lower roller is 1.5 mm. In addition, the pressure applied by the air knife is 0.6 MPa, and the pressure of the high-pressure water is set to 10 bar. Most of the fine impurities in the raw materials of tertiary cotton and cotton linter are removed under these process parameters.

[0054] From Figures 4 to 6 It can be seen that the effect of the peeling off of the black skin on the epidermal layer of the raw materials of Broussonetia papyrifera, mulberry bark, and Pteroceltis tatarinowii is obvious after treatment; Table 1 shows the comparison of the data of the peeling off of fine impurities in the raw materials of tertiary cotton and cotton linter before and after.

[0055] Table 1: Comparison of the data of the peeling off of fine impurities in the raw materials of tertiary cotton and cotton linter before and after

[0056] raw material impurity content before treatment impurity content after treatment grade 3 cotton ～1.5％ ～0.8％ cotton linter ～6.0％ ～3.0％

[0057] The above embodiments are the preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. A pulping raw material impurity removal device, characterized in that: It includes a gap pressurizing area and a separation processing area; the gap pressurizing area includes a driving motor and a gap pressurizing device; the separation processing area includes an air knife system, a high-pressure water spraying device, and a mesh conveyor belt; The gap pressure device comprises a pair of rolling roller bodies, a pair of gap digital display meters and a pair of gap adjustment components; the pair of rolling roller bodies comprises an upper roller and a lower roller, the upper roller is a fixed roller, and the lower roller is a movable roller; the gap adjustment component comprises a positive and negative thread screw, a wedge block and a fixed plate, the positive and negative thread screw passes through the fixed plate located in front of the wedge block to keep it horizontal, the tail of the positive and negative thread screw is threadedly connected to the wedge block, and the bearing of the lower roller is located above the wedge block; The outlet of the gap pressurizing zone is connected to the mesh conveyor belt, and the air knife system and the high-pressure water spray device are located above the mesh conveyor belt.

2. The pulping raw material impurity removal device according to claim 1, characterized in that: The line pressure between the upper roller and the lower roller is ≥100KN / m, the upper roller speed is greater than the lower roller speed and the speed difference between the upper and lower rollers is 4-7%; the roller surface is processed by twill knurling, and the knurling modulus is 0.2-0.4mm.

3. The pulping raw material impurity removal device according to claim 2, characterized in that: The gap adjustment range of the gap adjustment component is 0.5-25 mm, and the adjustment accuracy is 0.1 mm; the gap digital display is used to measure and display the gap data between the upper and lower rollers.

4. The pulping raw material impurity removal device according to claim 3, characterized in that: The driving motor is electrically connected to the rolling roller body, and the motor speed is 5-25 m / min.

5. The pulping raw material impurity removal device according to claim 4, characterized in that: The wind knife system includes a wind knife and an air supply device. The wind knife system is close to the outlet of the gap pressurization zone. The angle between the wind knife and the mesh conveyor belt is 30° to 45°, and the wind knife surface width is 250mm. The air supply device provides a pressure of not less than 0.6MPa, and the exhaust volume is 1m 3 / min.

6. The pulping raw material impurity removal device according to claim 5, characterized in that: The high-pressure water spray device is located behind the air knife system, the spray width is the same as the roller surface width, and the water pressure is not less than 10 bar.

7. The pulping raw material impurity removal device according to claim 6, characterized in that: The pulping raw materials are one or more of mulberry bark, mulberry bark, euphorbia cerasifera bark, third-grade cotton and cotton linters.

8. A method for using the pulping raw material impurity removal device according to any one of claims 1 to 7, characterized in that: The following steps are involved: (1) Select the knurling modulus of the upper and lower rollers, set the upper and lower roller speeds, set the pressurized gap, check the air knife angle and the working parameters of the air supply device, start the high-pressure water spray device, and send the pulping raw materials into the gap pressurized area; (2) After the treatment is completed, the pulping raw material with impurities removed is obtained at the end of the mesh conveyor belt.

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