Production tower and production method for dry processing of wood fiber micro-nano powder

Abstract

The present invention discloses a dry processing production tower for wood fiber micro-nano powder and a method thereof, comprising a crushing device, a cylinder, a discharge pipe, an ascending separation pipe, a feeding pipe, an air inlet pipe and a bracket; the bottom of the cylinder is supported by the bracket, and the feeding pipe and the air inlet pipe feed and take in air from the bottom of the cylinder upwards, the crushing device is installed in the middle of the cylinder, a feeding port is provided at the bottom of the crushing device, and a dropping port is provided at the top; a ascending separation pipe is provided above the crushing device, and the ascending separation pipe is connected to the discharge pipe; the air inlet pipe supplies air intermittently, and wood fiber enters the crushing device during blowing, and raw materials with a diameter as small as a certain size after crushing enter the discharge pipe under the action of the wind force of the blowing air; raw materials that do not enter the discharge pipe during the air rest period fall back to the crushing device, are crushed again and blown again, and raw materials with a diameter as small as a certain size after crushing ascend the separation pipe under the action of the wind force of the blowing air and enter the discharge pipe, and so on.

Description

Technical Field

[0001] The invention belongs to the field of wood fiber processing devices, and particularly relates to a wood fiber micro-nano powder dry processing production tower and a production method. Background Art

[0002] Biomass resources produced by plant photosynthesis include natural polymers such as starch and wood fiber. Wood fiber is the most abundant biomass resource in nature, widely distributed in agricultural straw, trees, and grasses. It boasts diverse resources, is renewable, biodegradable, and non-food. Research on wood fiber has attracted widespread attention from researchers across multiple disciplines, including chemistry, physics, biology, and materials science, and has driven the large-scale application of wood fiber-based functional materials in areas such as papermaking, spinning, film production, and chemical production. The dense network of hydrogen bonds within wood fibers and the strong intermolecular bonding forces result in the high energy required to separate them. Currently, the micronization and nanofiberization of wood fibers is primarily achieved through wet processing, including chemical, biological, and mechanical methods. These methods involve immersing the wood fibers in a solution for micronization and nanofiberization. These methods are associated with environmental pollution, high energy consumption, and low production efficiency. Therefore, the development of dry mechanical processing equipment to efficiently and environmentally friendly prepare micronized wood fiber powder containing lignin is of great significance.

[0003] Patent application publication number JP2020199498A discloses a pulverization device, pulverization method, and method for producing free-radicalized lignocellulose micropowder. This patent relates to dry processing methods for wood fibers. The pulverization method uses a dry pulverizer to pulverize lignocellulose-derived biomass. Ozone gas is introduced from an external source, and the pulverized biomass is pulverized in an ozone atmosphere. The pulverization medium in the disclosed pulverization device comprises multiple disc-shaped or ring-shaped pulverization media stacked axially within a cylindrical pulverization container. The inflow port is the cylindrical pulverization medium. This nozzle, located on the end or outer surface of the container, injects or discharges ozone gas into the cylindrical grinding container. The rolling of the grinding media increases the impact force on the biomass. However, the device requires pulverization in an ozone-filled environment, which cannot be reused, increasing the pulverization cost. This device cannot directly control the size of the powder, making it difficult to achieve micro- and nano-scale sizes. The device is too small to be mass-produced, and during operation, the high-speed rolling of the grinding media increases its loss, and the replacement of the grinding media is difficult. Summary of the Invention

[0004] The present invention addresses the problems existing in the prior art in the process of wood fiber comminution. The present invention discloses a production tower and a production method for dry processing of wood fiber micro-nano powder, which enables wood fiber to be efficiently processed into micro-nano sized powder without solution infiltration.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] The present invention also provides a production tower for dry processing of wood fiber micro-nano powder, comprising a crushing device, a cylinder, a discharge pipe, an ascending separation pipe, a feed pipe, an air inlet pipe and a bracket;

[0007] The bottom of the cylinder is supported by a bracket, and the feed pipe and the air inlet pipe feed and intake air from the bottom of the cylinder upward. The crushing device is installed in the middle of the cylinder, and a feed port is set at the bottom of the crushing device, and a drop port is set at the top; a rising separation pipe is set above the crushing device, and the rising separation pipe is connected to the discharge pipe; the air inlet pipe supplies air intermittently, and the wind force of the air inlet pipe can make the wood fiber pass through the crushing device and rise to the rising separation pipe. Raw materials with small diameter enter the discharge pipe, and raw materials with large diameter fall back to the crushing device, and then rise to the rising separation pipe and enter the discharge pipe after being crushed again.

[0008] As a further technical solution, the upper part of the upper cylinder is conical, and its center is connected to the rising separation pipe. The bottom of the lower cylinder is conical, and its center is connected to the air intake pipe. The feed pipe is located on one side of the air intake pipe and is connected to the air intake pipe.

[0009] As a further technical solution, static eliminators are provided on both the cylinder and the rising separation pipe.

[0010] As a further technical solution, the wind force of the air inlet pipe can make the raw materials rise to the rising separation pipe, and the air inlet pipe is an intermittent air supply.

[0011] As a further technical solution, an electrostatic eliminator is also provided on the cylinder.

[0012] As a further technical solution, the crushing device is detachably mounted on the cylinder.

[0013] As a further technical solution, the crushing device is a magnetic crushing device, a rotating blade crushing device, a grinding disc crushing device or a spherical graphite crushing device.

[0014] As a further technical solution, the magnetic crushing device includes an annular crushing cavity, which is filled with magnets and wood fibers; multiple electromagnetic drive devices are installed on the circumferential direction of the annular crushing cavity, and a gravitational device is provided on the inner ring of the annular crushing cavity. The electromagnetic drive device drives the magnet to move in the annular crushing cavity at a set speed. The gravitational force generated by the gravitational device is used to offset the centrifugal force generated during the circular motion of the magnet, so that the magnet can move rapidly in a circular motion in the cavity and collide with the wood fiber particles.

[0015] As a further technical solution, the discharge pipe is arranged at an angle, with the top connected to the rising separation pipe and the bottom being the discharge port for the wood fiber particles.

[0016] In a second aspect, the present invention further discloses a dry processing method for wood fiber micro-nano powder, wherein the wood fiber is processed using the production tower as described above, specifically as follows:

[0017] Connect the air inlet pipe to the blower. First, control the wind force of the blower to lift the material to the separation port of the ascending separation pipe above the crushing device. Then, stop the blower, and the material that meets the particle size requirements will enter the discharge pipe. The material that does not meet the particle size requirements will fall freely to the crushing device due to gravity, and then be crushed again together with the new material coming from the feed pipe.

[0018] After the crushing device has been crushing for a period of time, the blower is started again. At this time, the wind force of the blower is controlled to be able to blow the material to the upper separation port of the rising separation tube. Then the blower is stopped, so that the material that meets the particle size requirements will enter the discharge pipe. The material that does not meet the particle size requirements will fall freely to the crushing device due to gravity and be crushed again together with the new material, and the cycle continues. The separation of different particle sizes can be well achieved through intermittent blowing.

[0019] The beneficial effects of the above embodiments of the present invention are as follows:

[0020] The air inlet pipe of the production tower proposed by the present invention adopts an intermittent blowing method to separate powders of different sizes. At the same time, the intermittent blowing method can use the effect of gravity to make the materials that do not meet the particle size requirements fall back to the crushing device for crushing, thereby realizing the separation and processing of particles of different particle sizes. The intermittent method can reduce the energy consumption of the equipment and is conducive to the realization of continuous processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0022] Figure 1 This is a schematic diagram of a production tower for dry processing of wood fiber micro-nano powders proposed in the present invention;

[0023] Figure 2 It is the pulverization principle and motion analysis diagram of the mechanical device for dry processing of wood fiber micro-nano powder;

[0024] Figure 3 、 Figure 4 is a schematic diagram of a magnetic pulverization device used in some embodiments of the present invention;

[0025] In the figure: 1, discharge port, 2, discharge pipe, 3, static eliminator, 4, rising separation pipe, 5, static eliminator, 6, upper cylinder, 7, crushing device, 8, lower cylinder, 9, feed pipe, 10, air inlet pipe, 11, lower end bracket;

[0026] 7-1. Condenser, 7-2. Upper condenser cover, 7-3. Upper conical cover, 7-4. Accelerating magnet, 7-5. Accelerating magnetic induction coil, 7-6. Top cover, 7-7. Lower condenser cover, 7-8. Bottom cover, 7-9. Gravitational magnet condenser, 7-10. Condenser water inlet, 7-11. Lower conical cover, 7-12. Condenser water outlet, 7-13. Grinding inner wall, 7-14. Grinding outer wall, 7-15. Equipment outer wall, 7-16. Equipment inner wall, 7-17. Static eliminator, 7-18. Tester, 7-19. Accelerating magnet condenser, 7-20. Gravitational magnetic induction coil, 7-21. Crushing cavity, 7-22. Gravitational magnet, 7-23. Discharge port. DETAILED DESCRIPTION

[0027] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0028] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless otherwise clearly indicated in the present invention, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "include" and / or "comprising" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations;

[0029] As introduced in the background technology, in the prior art, due to the densely distributed network hydrogen bond structure inside the wood fiber raw materials and the strong intermolecular binding force, the micro-nano separation of wood fibers requires a large amount of energy to separate them, and wood fibers contain a large amount of lignin, which is an important component of the cell wall and has the function of enhancing the hardness and stability of plants. That is, in order to prepare micro-nano fiber powder containing lignin, a grinder with a higher speed is required, which consumes more heat, and the addition of solvent is required to prevent gelatinization during the micro-nano grinding process of the wood fibers. This embodiment discloses a dry processing production tower and method for wood fiber micro-nano powder, which enables wood fibers to be efficiently processed into micro-nano sized powder substances without solution infiltration.

[0030] The present invention is described in detail below with reference to the accompanying drawings:

[0031] This embodiment discloses a detailed structure of a production tower for dry processing of wood fiber micro-nano powder, such as Figure 1 As shown, the production tower disclosed in this embodiment includes a crushing device 7, a discharge pipe 2, a first static eliminator 3, an ascending separation pipe 4, a second static eliminator 5, an upper cylinder 6, a lower cylinder 8, a feed pipe 9, an air inlet pipe 10, a lower end bracket 11, etc.;

[0032] A lower cylinder 8 is provided on the top of the lower end bracket 11, and a feed pipe 9 and an air inlet pipe 10 are provided inside the lower end bracket 11; the top of the lower cylinder 8 is a replaceable crushing device 7, the top of the replaceable crushing device 7 is the upper cylinder 6, the top of the upper cylinder 6 is the rising separation pipe 4, and the rising separation pipe 4 is connected to the discharge pipe 2; that is, the crushing device 7 is provided between the lower cylinder 8 and the upper cylinder 6, and is detachably connected to the lower cylinder 8 and the upper cylinder 6, and a feed port is provided at the bottom of the crushing device 7, a discharge port is provided at the top, and other positions are sealed; so that the particles entering from the lower feed pipe 9 can only enter the rising separation pipe 4 above from the crushing device 7;

[0033] The above-mentioned production tower adopts intermittent blowing. The raw materials enter the equipment through the feed pipe 9, and the air inlet pipe 10 is blown to blow the raw materials into the equipment. The raw materials can pass through the crushing device 7 and enter the ascending separation pipe 4. Then part of the raw materials reaches the discharge pipe 2 and exits from the discharge pipe 2. Part of the raw materials falls back to the crushing device 7, is crushed again, enters the ascending separation pipe 4 and then reaches the discharge pipe 2 and exits from the discharge pipe 2.

[0034] Specifically, the wind force is controlled to be able to lift the material to the upper separation port. At this time, the blower stops, allowing the raw materials to freely fall to the crushing area for crushing. Intermittent blowing can effectively separate particles of different sizes. According to the crushing situation, the blower is turned on again to blow air, and the wind force is still controlled at the level when it was stopped last time. At this time, smaller particles will be blown into the discharge pipe. Particles that have not reached the target size will freely fall to the crushing area for crushing again when the blower stops next time. When the air is blown again, the finer particles rise and separate into the discharge port. The larger particles continue to fall into the crushing device under the action of gravity and continue to be crushed. At the same time, new raw materials continue to enter the crushing device through the feed pipe and are crushed again together with the large particles that fall in. This process repeats again and again to prepare wood fibers with the required composite particle size and enter the next production tower for finer crushing.

[0035] Furthermore, the above-mentioned discharge pipe 2, rising separation pipe 4, upper cylinder 6, lower cylinder 8, and lower end bracket 11 are wrapped with carbon steel, wherein the discharge pipe 2 is set at an angle, its top is connected to the rising separation pipe 4, and the bottom is the discharge port 1 of the wood fiber particles.

[0036] Furthermore, the upper portion of the upper cylinder 6 in this embodiment is conical, and its center is connected to the ascending separation pipe 4. The bottom of the lower cylinder 8 is conical, and its center is connected to the air inlet pipe 10. The feed pipe 9 is located on one side of the air inlet pipe 10 and is connected to the air inlet pipe 10. That is, the wood fiber particles enter the air inlet pipe and, under the action of the gas, fill the lower cylinder. Then, under the action of the gas coming in from the air inlet pipe, the wood fiber particles move upward and reach the crushing device, and then are crushed.

[0037] Furthermore, the blower is a main intermittent blowing device, which can adjust the blowing force and blowing time. The blower is connected to the air inlet pipe 10.

[0038] Furthermore, the rising separation tube 4 has a certain height, which can fully separate large and small materials; materials that meet the target size are discharged through the discharge pipe 2, and materials that do not meet the target size fall back into the replaceable magnetic crushing device so that they can be fully crushed.

[0039] Furthermore, an electrostatic eliminator 5 is provided on the side wall of the upper cylinder 6, and an electrostatic eliminator 3 is also provided on the rising separation pipe 4; in this embodiment, the electrostatic eliminator 3 and the electrostatic eliminator 5 perform high-voltage discharge at the tip from time to time, so that the static electricity of the wood fiber raw materials adhering to the discharge pipe 2, the rising separation pipe 4, and the cavity wall of the upper cylinder 6 is eliminated, so that the wood fiber raw materials can be better crushed, and at the same time, the wood fiber raw materials are prevented from being excessively adhered to the discharge pipe 2, the rising separation pipe 4, and the upper cylinder 6, making it difficult to reduce the temperature and the material yield low.

[0040] Furthermore, the static eliminator 3 and the static eliminator 5 use air source DC electronic wind rods.

[0041] Furthermore, the above-mentioned discharge pipe 2, rising separation pipe 4, upper cylinder 6, lower cylinder 8, and lower end bracket 11 are made of high-quality carbon steel, such as No. 45 carbon steel, No. 60 carbon steel, 60M carbon steel, etc., but not limited to the above three types of carbon steel.

[0042] Furthermore, the thickness of the discharge pipe 2, the ascending separation pipe 4, the upper cylinder 6, and the lower cylinder 8 is 10-20 mm.

[0043] Furthermore, the crushing device in this embodiment can be a magnetic crushing device, a rotating blade crushing device, a grinding disc crushing device or a spherical graphite crushing device. This embodiment uses a magnetic crushing device, such as Figure 3 、 Figure 4 As shown, it mainly includes an annular crushing cavity, a driving device and a gravitational device; specifically, the annular crushing cavity is filled with magnets and wood fibers; multiple electromagnetic driving devices are mounted on the annular crushing cavity along its circumferential direction, and a gravitational device is provided on the inner ring of the annular crushing cavity. The electromagnetic driving device drives the magnet to move at a set speed in the annular crushing cavity, and the gravitational force generated by the gravitational device is used to offset the centrifugal force generated during the circular motion of the magnet, so that the magnet can quickly perform a circular motion in the cavity and collide with the wood fiber particles;

[0044] Specifically, the annular crushing cavity is composed of a grinding inner wall 7-13 and a grinding outer wall 7-14. The grinding inner wall 7-13 and the grinding outer wall 7-14 are combined to form an annular crushing cavity. An annular feed port is set at the top of the annular crushing cavity and an annular feed port is set at the bottom. After passing through the annular crushing cavity, the material moves upward;

[0045] The driving device includes a plurality of accelerating magnets 7-4 and accelerating magnetic induction coils 7-5. An accelerating magnetic induction coil 7-5 is wound around each accelerating magnet 7-4. The electromagnetic driving device drives the magnet to move in the annular crushing cavity at a set speed.

[0046] The gravitational device includes multiple gravitational magnets 7-22 arranged radially along the inner ring of the crushing cavity. Each gravitational magnet 7-22 is equipped with a gravitational magnetic induction coil 7-20. The gravitational force generated by the gravitational device is used to offset the centrifugal force generated during the circular motion of the magnet, allowing the magnet to rapidly move in a circular motion within the cavity and collide with the wood fiber particles. During the crushing process, the acceleration magnetic induction coil 7-5 drives the magnet, while the acceleration magnet 7-4 confines the magnet to the cavity formed by the annular crushing cavity, preventing it from colliding with the crushing cavity and reducing magnet wear. After the material is crushed, the gravitational device in the middle of the magnetic crushing generates a sufficient gravitational force to attract the magnet and firmly adhere it to the inner wall of the crushing cavity. The magnet is accelerated by the magnetic coil, giving it a certain speed. By changing the current flowing through the magnetic coil, the magnet's rotation speed is increased. The magnet is continuously accelerated in the magnetic field. Under the action of centrifugal force, the magnet will rotate closely against the outer wall, resulting in it being unable to collide with the wood fibers to crush them. This also consumes a lot of energy. Therefore, gravity is required to offset the centrifugal force generated by the magnet's circular motion, allowing the magnet to quickly move in a circular motion within the cavity and collide with the wood fiber particles to crush them. The magnet can also be measured by a tester 7-18 to measure the magnet's instantaneous speed or the distance from the inner and outer walls. The value is transmitted to the gravitational magnetic induction coil 7-20 through a control element. Based on the different instantaneous speeds transmitted, the generated centrifugal force is calculated, causing the gravitational magnetic induction coil 7-20 to generate a corresponding magnetic force, which is then confined to a designated area of ​​the crushing cavity 7-21, preventing the magnet from colliding with the crushing cavity 7-21, reducing magnet loss, and limiting the magnet's movement area.

[0047] Furthermore, the condensation device is located in the outer ring of the annular crushing cavity, which is formed by combining the outer wall 7-15 of the equipment, the inner wall 7-16 of the equipment, the upper condensation tube cover 7-2, the condensation tube 7-1 and the lower condensation tube cover 7-7.

[0048] Condensers are also provided on the accelerating magnet and the attracting magnet, the accelerating magnet condenser 7-19 and the attracting magnet condenser 7-9, which together cool down the wood fibers during the crushing process.

[0049] Furthermore, an upper conical cover 7-3 is provided above the annular crushing cavity, the driving device and the gravity device, and a lower conical cover 7-11 is provided below, mainly to scatter the wood fiber particles falling from above into the annular crushing cavity and to drain the wood fiber particles entering from below into the annular crushing cavity.

[0050] Example 2

[0051] This embodiment provides a production method based on the production tower for dry processing of wood fiber micro-nano powder disclosed in Example 1, as follows:

[0052] Connect the air inlet pipe 10 to the blower, and start feeding the material through the feed pipe 9. First, the wind force of the blower is controlled to be able to lift the material to the separation port of the ascending separation pipe 4 above the pulverizing device. Then, the blower is stopped, and the material that meets the particle size requirements will enter the discharge pipe 2. The material that does not meet the particle size requirements will fall freely to the pulverizing device 7 due to gravity, and then be pulverized again together with the new material coming in from the feed pipe 9.

[0053] After the crushing device has been crushing for a period of time, the blower is started again. At this time, the wind force of the blower is controlled to be able to blow the material to the upper separation port of the rising separation pipe 4, and then the blower is stopped, so that the material that meets the particle size requirements will enter the discharge pipe 2, and the material that does not meet the particle size requirements will freely fall to the crushing device due to gravity, and be crushed again together with the new material, and the cycle is repeated; the separation of different particle sizes can be well achieved through intermittent blowing.

[0054] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A production tower for dry processing of wood fiber micro-nano powder, characterized in that: It includes a crushing device, a cylinder, a discharge pipe, an ascending separation pipe, a feed pipe, an air inlet pipe and a bracket; The bottom of the cylinder is supported by a bracket, and the feed pipe and the air inlet pipe are used to feed and intake air upward from the bottom of the cylinder. The crushing device is installed in the middle of the cylinder, and the feed port is set at the bottom of the crushing device and the discharge port is set at the top; an ascending separation pipe is set above the crushing device, and the ascending separation pipe is connected to the discharge pipe; the air inlet pipe supplies air intermittently, and when blowing air, the wood fiber enters the crushing device, and the raw materials with a diameter of a certain size after crushing enter the discharge pipe; when the air is resting, the raw materials that have not entered the discharge pipe fall back to the crushing device to be crushed again, and after being crushed again, they rise to the separation pipe and enter the discharge pipe, and so on. The crushing device is a magnetic crushing device, which includes an annular crushing cavity filled with magnets; multiple electromagnetic driving devices are installed on the circumferential direction of the annular crushing cavity, and a gravitational device is provided on the inner circle of the annular crushing cavity. The electromagnetic driving device drives the magnet to move in the annular crushing cavity at a set speed. The gravitational force generated by the gravitational device is used to offset the centrifugal force generated during the circular motion of the magnet, so that the magnet can move rapidly in a circular motion in the cavity and collide with the wood fiber particles.

2. The production tower for dry processing of wood fiber micro-nano powder according to claim 1, characterized in that: The cylinder includes an upper cylinder and a lower cylinder. The upper part of the upper cylinder is conical, and its center is connected to the rising separation pipe. The bottom of the lower cylinder is conical, and its center is connected to the air intake pipe. The feed pipe is located on one side of the air intake pipe and is connected to the air intake pipe.

3. The production tower for dry processing of wood fiber micro-nano powder according to claim 1, characterized in that: An electrostatic eliminator is provided on the ascending separation pipe.

4. The production tower for dry processing of wood fiber micro-nano powder according to claim 1, characterized in that: An electrostatic eliminator is also provided on the cylinder.

5. The production tower for dry processing of wood fiber micro-nano powder according to claim 1, characterized in that: The magnetic crushing device is detachably mounted on the cylinder.

6. The production tower for dry processing of wood fiber micro-nano powder according to claim 1, characterized in that: The discharge pipe is arranged obliquely, with the top connected to the rising separation pipe and the bottom being the discharge port for the wood fiber particles.

7. A dry processing method for wood fiber micro-nano powder, characterized in that: The processing is carried out using the production tower described in any one of claims 1 to 6.

8. The dry processing method of wood fiber micro-nano powder according to claim 7, characterized in that: as follows: Connect the air inlet pipe to the blower and start feeding the material through the feed pipe; The blower's wind force is controlled to lift the material to the separation port of the ascending separation pipe above the pulverizing device. Then, the blower stops, and the material that meets the particle size requirements will enter the discharge pipe. The material that does not meet the particle size requirements will fall freely to the pulverizing device due to gravity, and then be pulverized again together with the new material coming from the feed pipe. After the crushing device has been crushing for a period of time, the blower is started again. At this time, the wind force of the blower is controlled to be able to blow the material to the upper separation port of the rising separation tube. Then the blower is stopped, so that the material that meets the particle size requirements will enter the discharge pipe. The material that does not meet the particle size requirements will fall freely to the crushing device due to gravity and be crushed again together with the new material, and the cycle continues. The separation of different particle sizes can be well achieved through intermittent blowing.

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