Device for improving reaction activity of fibers

Abstract

The utility model relates to a device for improving fiber reaction activity. The device comprises a pulping machine and a grinding disc body arranged in the pulping machine, a cutting area, a crushing area, a coarse grinding area and a fine grinding area are sequentially arranged on the grinding disc body; wherein the cutting area, the crushing area, the coarse grinding area and the fine grinding area are respectively arranged on the grinding disc body from the root to the outer edge, and the grinding disc has the advantages that roll-shaped cellulose is ground into fluffy fibers after being pre-crushed and ground, so that the fluffy fibers are formed, and the cutting area, the crushing area, the coarse grinding area and the fine grinding area are arranged on the grinding disc body; the device is favorable for improving the permeation of a reaction reagent, improving the reaction activity of cellulose, improving the evenness and grinding quality of a cellulose material, and improving the grinding efficiency.

Description

Technical Field

[0001] The utility model belongs to the technical field of cellulose grinding and relates to a device for improving the reaction activity of fibers. Background Art

[0002] Acetate-grade cellulose is the primary raw material for producing cellulose acetate products. Common commercial cellulose acetate grades are in coiled form. Because cellulose acetate conversion is a heterogeneous reaction, to enhance the reactivity of cellulose, the coiled cellulose needs to be pre-crushed and ground into fluffy fibers. This facilitates the penetration of reagents and increases the reactivity of the cellulose.

[0003] Existing cellulose grinding equipment is typically developed based on the characteristics of hardwood pulp fibers. However, in actual production, different fiber types, such as softwood pulp, cotton, and hemp, need to be ground. This is typically accomplished using a refiner, where the refining discs are a key component affecting the quality and yield of the refined pulp. Refining discs are composed of a single unit or a combination of individual units. These discs come in a variety of configurations, including disc-type, conical-type, and cylindrical-type. However, they all utilize one, a set of two, or both sets of moving discs fixed to a rotating disc and a fixed disc fixed to a mounting disc. The rotating disc is driven by a power source and can move axially or radially to adjust the gap between the moving and fixed discs. Materials containing wood or similar fibers are primarily processed and separated within this gap. However, conventional refining discs are not fully suitable for grinding acetate-grade cellulose, which is made from long, coarse fibers such as softwood and cotton. In the process of grinding cotton fibers, problems such as insufficient grinding of bulk solids, fiber knotting, blockage of fiber conveying after grinding, and low grinding efficiency often occur.

[0004] Compared with traditional hardwood pulp, softwood fiber and cotton pulp fiber have the characteristics of long fibers, thick walls, and high crystallinity. The average length of hardwood pulp fibers is between 0.74-0.76mm, and the average fiber width is between 15.8-16.3μm. The morphological characteristics of softwood fiber and cotton pulp fibers are significantly different, with an average fiber length between 2.45-3.75mm and an average fiber width between 18.3-19.6μm. Compared with softwood fiber and cotton fiber, grinding is more difficult, less effective, and less efficient. Therefore, designing an acetate-grade cellulose grinding device suitable for softwood fiber and cotton fiber as raw materials is of great significance to the development and industrialization of new pulp raw materials. Utility Model Content

[0005] The purpose of the utility model is to solve the above problems existing in the prior art and to provide a device for improving the reactivity of fibers.

[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0007] A device for improving fiber reactivity comprises a pulping machine and a grinding disc body installed in the pulping machine; the grinding disc body is sequentially provided with a cutting area, a crushing area, a coarse grinding area and a fine grinding area; wherein the cutting area, the crushing area, the coarse grinding area and the fine grinding area are respectively arranged on the grinding disc body from the root to the outer edge.

[0008] Preferably, the grinding disc body is in a disc structure or a square structure.

[0009] Preferably, a plurality of irregular conical heads are provided on the cutting area; wherein the plurality of conical heads are combined together and arranged in a ring shape.

[0010] Preferably, the surface of the conical head is smooth, the edges and corners are sharp, and the top is an inverted triangle structure; wherein, the angle formed by two adjacent conical heads with the grinding disc body as the center is 15-30 degrees.

[0011] Preferably, a plurality of annular grinding groups are provided on the crushing zone; wherein each annular grinding group is provided with a plurality of grinding protrusions.

[0012] Preferably, the grinding protrusions are in the shape of a three-dimensional inverted triangle with sharp edges and corners; preferably, each group of grinding protrusions is arranged crosswise and at an angle of 15-30 degrees; the spacing between grinding protrusions in the same group is 0.6-0.8 mm, and the spacing between grinding protrusions between adjacent groups is 1-1.5 cm.

[0013] Preferably, the coarse grinding area is composed of two groups of three-dimensional small triangular pyramid rings, and the small triangular pyramid rings include multiple small triangular pyramids and multiple first baffles, wherein the small triangular pyramids and the first baffles are connected end to end to form a circular track.

[0014] Preferably, the small triangular pyramids on the two groups of small triangular pyramid rings are arranged in a cross-arrangement with a cross-arrangement angle of 15 degrees; the distance between the rings is 0.2-0.5 mm; preferably, the spacing between adjacent small triangular pyramids is 0.6-0.8 mm.

[0015] Preferably, the fine grinding area is composed of three groups of three-dimensional large triangular pyramid rings, and the large triangular pyramid rings include multiple large triangular pyramids and multiple second baffles, wherein the large triangular pyramids and the second baffles are connected end to end to form a circular track.

[0016] Preferably, the distance between adjacent large triangular pyramid rings is 0.1-0.3 mm; wherein, the spacing between adjacent large triangular pyramids on the large triangular pyramid ring is 0.2-0.6 mm.

[0017] Due to the adoption of the above technical solution, the beneficial effects obtained by the utility model include:

[0018] The utility model grinds the rolled cellulose into fluffy fibers by pre-crushing and grinding the rolled cellulose, which is beneficial to improving the penetration of reaction reagents and the reaction activity of cellulose, improving the evenness and grinding quality of the cellulose material, and improving the grinding efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of an embodiment of a device for improving fiber reactivity according to the present invention.

[0020] Figure 2 It is a partial cross-sectional view of an embodiment of the device for improving fiber reactivity of the present invention.

[0021] The reference numerals are as follows:

[0022] 1. Grinding disc body; 2. Cutting area; 21. Conical head;

[0023] 3. Crushing area; 31. Ring grinding group; 32. Grinding protrusion;

[0024] 4. Rough grinding area; 41. Small triangular pyramid ring; 42. Small triangular pyramid; 43. First stop bar;

[0025] 5. Fine grinding area; 51. Large triangular cone ring; 52. Large triangular cone; 53. Second stop bar;

[0026] 6. Channel. DETAILED DESCRIPTION

[0027] Please attend Figure 1 、 Figure 2 As shown, the utility model mainly provides a device for improving the reactivity of fibers, which includes a refiner and a refiner body installed in the refiner; wherein, the refiner body 1 can grind acetate-grade cellulose made of cotton fibers as raw materials under the action of the refiner.

[0028] In this embodiment, the grinding disc body 1 is a disc structure, and a cutting area 2, a crushing area 3, a coarse grinding area 4 and a fine grinding area 5 are sequentially arranged on the grinding disc body 1; wherein, the cutting area 2, the crushing area 3, the coarse grinding area 4 and the fine grinding area 5 are respectively arranged from the root to the outer edge of the grinding disc body 1. This arrangement can well facilitate the acetate-grade cellulose from the initial strip cutting to the subsequent fine grinding, thereby regularly improving the reactivity of the cotton fiber and improving the quality and effect of grinding.

[0029] In this embodiment, the cutting area 2 is provided with a plurality of irregularly shaped conical heads 21; preferably, there are 18 of these heads 21, which are arranged in a ring. The surfaces of the conical heads 21 are smooth and sharp, with their tips forming inverted triangles and oriented in the same direction. The angle formed by two adjacent conical heads with the grinding disc as the center is 15-30 degrees. This arrangement is primarily used to further shorten the initially cut cellulose strips (by utilizing the sharp edges of the conical heads) to facilitate subsequent grinding.

[0030] After the cellulose strip material is cut in the cutting area 2, it will enter the crushing area 3 for preliminary crushing; in this embodiment, preferably, four annular grinding groups 31 are provided on the crushing area 3; wherein, each annular grinding group 31 is provided with multiple grinding protrusions 32; the grinding protrusions 32 are three-dimensional inverted triangles with sharp edges and corners; preferably, each group of grinding protrusions 32 is arranged in a cross-arrangement and at an angle of 15-30 degrees; the spacing between the grinding protrusions 32 in the same group is 0.6-0.8mm, and the spacing between the grinding protrusions between adjacent groups is 1-1.5cm; this setting can crush the cellulose strip material (the grinding protrusions 32 cooperate with each other and use their own edges and corners to crush it, and the crushed fiber material enters the next coarse grinding area).

[0031] In this embodiment, the coarse grinding zone 4 is composed of two sets of three-dimensional small triangular pyramid rings 41. The small triangular pyramid rings 41 include multiple small triangular pyramids 42 and multiple first bars 43. The small triangular pyramids 42 and the first bars 43 are connected end to end to form a circular track. The small triangular pyramids 42 on the two sets of small triangular pyramid rings 41 are arranged in a cross-arrangement with a cross-arrangement angle of 15 degrees. The distance between the rings is 0.3 mm. Preferably, the spacing between adjacent small triangular pyramids 42 is 0.6-0.8 mm. This arrangement can coarsely grind the crushed fiber material (by utilizing the vertical collision between the small triangular pyramids 42 of the grinding disc), and the provision of the first bars 43 can prevent the fiber from being sucked out before it is fully ground.

[0032] In this embodiment, the fine grinding area 5 is composed of three groups of three-dimensional large triangular pyramid rings 51, and the large triangular pyramid rings 51 include multiple large triangular pyramids 52 and multiple second baffles 53, wherein the large triangular pyramids 52 and the second baffles 53 are connected end to end to form a circular track; preferably, the distance between adjacent large triangular pyramid rings 51 is 0.2 mm; wherein, the spacing between adjacent large triangular pyramids 52 on the large triangular pyramid ring 51 is 0.4 mm. This setting is mainly used for secondary grinding of the fiber material in the coarse grinding area, thereby improving the grinding effect, which is beneficial to improving the penetration of the reaction reagents and improving the reaction activity of cellulose (because the fibers are subjected to mechanical forces during the beating process, the microfibrils at a certain position in the middle layer of the secondary wall are bent and deformed, and the gaps between the microfibrils are increased, which creates conditions for the fibers to absorb more water. The fibers without the primary wall removed appear smooth, stiff, and not easy to absorb water and swell. This is because the primary wall contains more lignin and has a network structure. Although it can absorb water, its swelling degree is very low. The outer layer of the primary wall is very thin, and it tightly surrounds the middle layer of the primary wall that can swell well. Therefore, it must also be removed during beating to separate the fine fibers in the middle layer of the secondary wall to achieve full swelling and fibrillation of the fibers).

[0033] In this embodiment, the conical head 21 on the cutting area 2, the grinding protrusion 31 on the crushing area 3, the small triangular pyramid 42 on the coarse grinding area 4 and the large triangular pyramid 52 on the fine grinding area 5 are all arranged on the same arc line, and a gap "channel 6" can be formed between adjacent "arc lines". During the process, through cutting-crushing-coarse grinding-fine grinding layer by layer, the material can be gradually discharged along the "channel 6" (the operation of the entire process is high-speed flow under the action of centrifugal force, and gradually overflows).

[0034] The following table compares the effects of the grinding disc of the present invention and the existing grinding disc (taking the grinding effects of cork fiber and cotton fiber before and after the improvement of the grinding disc as an example):

[0035]

[0036] The following methods are used for HAZE evaluation of acetification process:

[0037] (1) Weigh 6 g of ground fiber and place it in a sealed container;

[0038] (2) Weigh 300 g of mixed acid (mass production sampling) and 6 g of sulfuric acid (analytical grade), mix them, and pour them into the above container;

[0039] (3) After vibrating on an oscillator for 30 minutes, take a sample and test the HAZE using a Hunter Lab colorimeter.

[0040] During this period, the cellulose grinding effect can be tested using a JOHSON wood pulp cyclone classifier to obtain the ratio of flakes and nap.

[0041] Therefore, based on the above analysis, the grinding disc in the present invention has better cutting effect and better grinding effect than the traditional grinding disc.

[0042] It should be noted that: the utility model grinds the rolled cellulose into fluffy fibers through pre-crushing and grinding, which is beneficial to improving the penetration of reaction reagents and the reaction activity of cellulose, improving the uniformity and grinding quality of the cellulose material, and improving the grinding efficiency; at the same time, in the process, from the coarse grinding area to the fine grinding area, the spacing between adjacent small triangular pyramids changes from 0.6-0.8mm to 0.4mm between adjacent large triangular pyramids, and the friction between the fiber materials is increased by continuously reducing the effective space retained by the fiber material in the grinding plate body, so that the coarse-fine grinding can be more sufficient and the grinding effect is improved; the setting of the first gear bar and the second gear bar can block the fiber materials located in the two areas, delay the passing speed of the fiber materials in the upper area, increase the residence time of the fiber materials in the grinding area, and increase the refining effect.

[0043] The above descriptions and embodiments are intended to facilitate understanding and application of the present invention by those skilled in the art. Those skilled in the art will readily be able to make various modifications to these disclosures and apply the general principles described herein to other embodiments without requiring inventive effort. Therefore, the present invention is not limited to the above descriptions and embodiments. Improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A device for improving fiber reactivity, comprising a refiner and a refiner body installed in the refiner; characterized in that: The grinding disc body is sequentially provided with a cutting area, a crushing area, a coarse grinding area and a fine grinding area; wherein the cutting area, the crushing area, the coarse grinding area and the fine grinding area are respectively arranged from the root to the outer edge of the grinding disc body.

2. The device for improving fiber reactivity according to claim 1, characterized in that: The grinding plate body is in a disc structure or a square structure.

3. The device for improving fiber reactivity according to claim 1, characterized in that: The cutting area is provided with a plurality of irregular conical heads; wherein the plurality of conical heads are combined together and arranged in a ring shape.

4. The device for improving fiber reactivity according to claim 3, characterized in that: The surface of the conical head is smooth, the edges and corners are sharp, and the top is an inverted triangle structure; the angle formed by two adjacent conical heads with the grinding plate body as the center is 15-30 degrees.

5. The device for improving fiber reactivity according to claim 1, characterized in that: The crushing zone is provided with a plurality of annular grinding groups, wherein each annular grinding group is provided with a plurality of grinding protrusions.

6. The device for improving fiber reactivity according to claim 5, characterized in that: The grinding protrusions are in the shape of a three-dimensional inverted triangle with sharp edges and corners; preferably, each group of grinding protrusions is arranged crosswise and at an angle of 15-30 degrees; the spacing between grinding protrusions in the same group is 0.6-0.8mm, and the spacing between grinding protrusions in adjacent groups is 1-1.5cm.

7. The device for improving fiber reactivity according to claim 1, characterized in that: The coarse grinding area is composed of two groups of three-dimensional small triangular pyramid rings, and the small triangular pyramid rings include multiple small triangular pyramids and multiple first baffles, wherein the small triangular pyramids and the first baffles are connected end to end to form a circular track.

8. The device for improving fiber reactivity according to claim 7, characterized in that: The small triangular pyramids on the two groups of small triangular pyramid rings are arranged in a cross-arrangement with a cross-arrangement angle of 15 degrees; the distance between the rings is 0.2-0.5 mm; preferably, the spacing between adjacent small triangular pyramids is 0.6-0.8 mm.

9. The device for improving fiber reactivity according to claim 1, characterized in that: The fine grinding area is composed of three groups of three-dimensional large triangular pyramid rings, and the large triangular pyramid rings include multiple large triangular pyramids and multiple second baffles, wherein the large triangular pyramids and the second baffles are connected end to end to form a circular track.

10. The device for improving fiber reactivity according to claim 9, characterized in that: The distance between adjacent large triangular pyramid rings is 0.1-0.3 mm; wherein, the distance between adjacent large triangular pyramids on the large triangular pyramid ring is 0.2-0.6 mm.

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