A new jet mill

Abstract

The utility model relates to the technical field of airflow crushing device, more particularly, disclose a kind of novel airflow pulverizer, it includes: pulverizer main body;Smashing cavity, the rotation body formed by the rotation of double curve L1 around the central axis L2 of pulverizer main body, in pulverizer main body;Several air inlets, along the tangential direction of smashing cavity are set on pulverizer main body;Several nozzles, corresponding each air inlet, are installed in air inlet;Feeding component, in the upper of nozzle, is connected smashing cavity, for conveying material;Discharge port, with the central axis L2 of pulverizer main body as center, is set in the upper of pulverizer main body;Smashing cavity is the rotation body, compared with traditional cylindrical or flat cavity, can effectively improve material crushing uniformity, prevent local accumulation of material, improve the crushing processing efficiency of material.

Description

Technical Field

[0001] This utility model relates to the technical field of airflow pulverizing devices, and in particular to a novel airflow pulverizer. Background Technology

[0002] An air jet mill is a device used for pulverizing materials. Compressed air, after being filtered and dried, is injected at high speed into the pulverizing chamber through a Laval nozzle. At the confluence of multiple high-pressure airflows, the material is repeatedly pulverized by collision, friction, and shearing. The pulverized material moves to the grading zone with the rising airflow under the suction of the fan. Under the strong centrifugal force generated by the high-speed rotating grading turbine, coarse and fine materials are separated. Fine particles that meet the particle size requirements enter the cyclone separator and dust collector for collection through the grading wheel, while coarse particles fall back to the pulverizing zone for further pulverization until the material processing is completed.

[0003] In existing technologies, the grinding chamber inside air jet mills is mostly cylindrical or flat. In traditional cylindrical grinding chambers, the airflow tends to form areas with large velocity gradients near the cylinder wall and the center, resulting in uneven material grinding. Flat grinding chambers, on the other hand, suffer from uneven airflow distribution, causing materials to accumulate in localized areas. Both of these factors reduce the efficiency of material grinding and affect production progress. Utility Model Content

[0004] In view of the above problems, this utility model provides a new type of airflow pulverizer, the purpose of which is to improve the pulverization and processing efficiency of materials.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A novel airflow pulverizer is provided, comprising: a pulverizer body; a pulverizing chamber, which is a rotating body formed by a hyperbola L1 rotating around the central axis L2 of the pulverizer body and located inside the pulverizer body; a plurality of air inlets, which are arranged tangentially to the pulverizing chamber on the pulverizer body; a plurality of nozzles, which are installed inside each air inlet corresponding to each air inlet; a feeding component, which is located above the nozzles and connects to the pulverizing chamber for conveying materials; and a discharge port, which is opened above the pulverizer body with the central axis L2 of the pulverizer body as the center.

[0006] Furthermore, the expression for the hyperbola L1 is: y = a / x, where y is the length of the crushing chamber in meters; x is the diameter of the crushing chamber in meters; a is a constant; and 2.5 ≤ y / x ≤ 3.5.

[0007] Furthermore, y = 1.5m, x = 0.5m.

[0008] Furthermore, 6-8 nozzles are arranged in a circumferential array on the main body of the crusher; the angle between the central axis L3 of the nozzle and the central axis L2 of the main body of the crusher is α, 45°≤α≤60°.

[0009] Furthermore, on the horizontal plane of the crushing chamber at x=0.8m, six nozzles are arranged in a circular array on the main body of the crusher, with an air inlet diameter of 0.1m and α=50°.

[0010] Furthermore, the nozzle is a Laval nozzle.

[0011] Furthermore, the feeding component is a screw feeder or a vibrating feeder.

[0012] The beneficial effects of this invention are as follows: In this invention, the crushing chamber is in the shape of a rotating body. Compared with traditional cylindrical or flat chambers, the rotating crushing chamber formed by a hyperbola around the central axis L2 of the crusher body can guide the airflow to form a stable and uniform annular rotating flow field within the crushing chamber. It can optimize the internal structure and airflow path of the crushing chamber, allowing the material to come into more full contact with the supersonic airflow within the crushing chamber, increasing the probability and intensity of collisions between particles and between particles and airflow, thereby significantly shortening the crushing time and processing more material per unit time. Compared with traditional chambers, it can effectively improve the uniformity of material crushing, prevent local accumulation of material, and improve the crushing efficiency of the material. Attached Figure Description

[0013] Figure 1 This is a front view of the overall structure of the pulverizer provided in this application.

[0014] Figure 2 This is a top view of the nozzle installation provided in an embodiment of this application.

[0015] Among them, 1. Crusher body; 11. Crushing chamber; 12. Nozzle; 13. Feed inlet; 14. Discharge outlet. Detailed Implementation

[0016] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0017] Example 1 This application discloses a novel airflow pulverizer, comprising: a pulverizer body 1; a pulverizing chamber 11, which is a rotating body formed by a hyperbola L1 rotating around the central axis L2 of the pulverizer body 1, and located inside the pulverizer body 1; a plurality of air inlets, which are arranged tangentially on the pulverizer body 1 along the pulverizing chamber 11; a plurality of nozzles 12, which are installed inside each air inlet corresponding to the air inlet; a feeding component, which is located above the nozzles 12 and communicates with the pulverizing chamber 11 for conveying materials; and a discharge port 14, which is opened above the pulverizer body 1 with the central axis L2 of the pulverizer body 1 as the center.

[0018] In practical use, the material to be processed is conveyed by the feeding component and enters the crushing chamber 11 through the feeding port 13; superheated steam is injected into the crushing chamber 11 through the nozzle 12 to crush the material in the crushing chamber 11.

[0019] In this invention, the crushing chamber 11 is in the shape of a rotating body. Compared with traditional cylindrical or flat chambers, the rotating crushing chamber formed by a hyperbola around the central axis L2 of the crusher body 1 can guide the airflow to form a stable and uniform annular rotating flow field within the crushing chamber 11. It can optimize the internal structure and airflow path of the crushing chamber, allowing the material to come into more full contact with the supersonic airflow within the crushing chamber 11, increasing the probability and intensity of collisions between particles and between particles and airflow, thereby significantly shortening the crushing time and processing more material per unit time. Compared with traditional chambers, it can effectively improve the uniformity of material crushing, prevent local accumulation of material, and improve the crushing efficiency of the material.

[0020] In some embodiments, the pulverization efficiency of this invention can be increased by more than 30%. For example, for silicon carbide materials with high hardness, the pulverization capacity in a conventional cylindrical or flat cavity of the same volume is 50 kg per hour, while the pulverization capacity in the pulverization cavity 11 of the same volume in this invention can reach more than 80 kg per hour.

[0021] In this embodiment, the installation angle of the nozzle 12 can be flexibly adjusted to further regulate the airflow distribution and velocity field, ensuring that the movement trajectory of the material in the crushing chamber 11 is regular and stable, and that each particle undergoes a similar crushing process under the same crushing conditions, thereby obtaining a narrower particle size distribution and ensuring the consistency of product particle size. Compared with traditional cylindrical or flat chambers, this invention can reduce the standard deviation of product particle size distribution by more than 30%.

[0022] For example, in the pharmaceutical field, for some drug powders that require strict control of particle size uniformity, the standard deviation of particle size distribution of products produced in traditional cylindrical or flat cavities is basically maintained at 1.5, while this invention can reduce the standard deviation of particle size distribution to below 1.05.

[0023] Preferably, the expression for the hyperbola L1 is: y = a / x, where y is the length of the crushing chamber 11 in meters; x is the diameter of the crushing chamber 11 in meters; a is a constant; and 2.5 ≤ y / x ≤ 3.5.

[0024] It is worth mentioning that, in this embodiment, the central axis L2 of the crusher body 1 coincides with the y-axis in the expression of the hyperbola L1.

[0025] It is understandable that the specific value of 'a' can be determined based on actual working conditions and design requirements.

[0026] Preferably, 6-8 nozzles 12 are arranged in a circumferential array on the main body 1 of the crusher; the angle between the central axis L3 of the nozzle 12 and the central axis L2 of the main body 1 of the crusher is α, 45°≤α≤60°.

[0027] In this embodiment of the invention, the air inlet is opened tangentially along the crushing chamber 11, and the nozzle 12 is also installed tangentially along the crushing chamber 11. Compared with the conventional single air inlet or axial air inlet method, the tangentially set nozzle 12 can make the airflow fill the entire crushing chamber 11 more quickly, reduce the initial energy loss of the airflow, and improve the crushing efficiency.

[0028] Furthermore, by adjusting the position and angle of the nozzle 12, the distribution and velocity field of the airflow can be flexibly adjusted and optimized to meet the needs of different materials and crushing processes.

[0029] Specifically, the nozzle 12 is a Laval nozzle 12, which consists of a contraction section, a throat, and an expansion section, with a contraction ratio of 3–5; the contraction ratio is the ratio of the cross-sectional area of ​​the inlet contraction section of the nozzle to the cross-sectional area of ​​the throat.

[0030] Preferably, the contraction ratio is 4, which enables the airflow to accelerate rapidly during the contraction process, converting pressure energy into kinetic energy.

[0031] It is worth mentioning that the throat diameter can be flexibly designed according to the processing capacity of the equipment and the required supersonic airflow velocity; for example, for a device with a processing capacity of 200 kg per hour, the throat diameter is set to 15 mm; the expansion ratio of the expansion section is 2-3, which is the ratio of the cross-sectional area of ​​the expansion section outlet to the cross-sectional area of ​​the throat, which can ensure that the airflow is further accelerated to a supersonic state in the expansion section, and the outlet Mach number can reach 2.5-3.0.

[0032] Preferably, the multiple nozzles 12 are arranged in a multi-layer nested, multi-angle spraying layout. The inner nozzles 12 spray the main airflow at high speed to provide the main crushing power for the material; while the outer nozzles 12 spray auxiliary airflow at different angles and speeds.

[0033] Reference Figure 2 As shown in the view, the central axis of the nozzle 12 is L4, and the angle between L4 and the tangent L5 of the crushing chamber 11 is β, which is 30°≤β≤45°, so that the material is more evenly distributed in the crushing chamber 11 and the turbulence and vortex of the airflow are reduced.

[0034] Through the above-mentioned nozzle 12 installation design, this nozzle 12 layout can reduce the energy loss of the main airflow by about 15% and increase the dispersion of materials in the crushing chamber 11 by more than 20%, effectively improving the crushing effect and product quality.

[0035] It is worth mentioning that the nozzle 12 is made of high-temperature resistant and high-strength alloy materials, such as nickel-based superalloys, which can maintain good mechanical properties and corrosion resistance at high temperatures, ensuring the stability and reliability of the nozzle 12 under long-term high-speed airflow scouring. In actual operation, superheated steam enters the Laval nozzle 12 and is accelerated to supersonic speed before being sent into the crushing chamber 11 for crushing. The superheated steam can be provided by steam generated from heating water in an existing industrial boiler.

[0036] Specifically, the feeding component is a screw feeder or a vibrating feeder; any existing models of screw feeders and vibrating feeders on the market can be selected.

[0037] During operation, the material is evenly fed into the crushing chamber 11 through the feed inlet 13 by a screw feeder or vibrating feeder, and is fully mixed with the supersonic airflow ejected from the nozzle. Driven by the high-speed airflow, the material particles obtain extremely high speeds, reaching 300-500 m / s, forming a high-speed particle flow within the crushing chamber 11.

[0038] During their movement, these particles collide violently with each other at speeds reaching hundreds of meters per second. The immense impact force breaks the chemical bonds on the particle surface, resulting in particle fragmentation and refinement. Furthermore, guide vanes and baffles can be added inside the crushing chamber 11, causing frequent impacts and friction between the particles and the inner wall of the chamber, as well as the guide vanes and baffles. For example, when a particle strikes the guide vane at high speed, the instantaneous impact force can reach thousands of Newtons. Under the combined action of impact and friction, the particles are continuously crushed.

[0039] Furthermore, the guide vanes and baffles can change the direction of airflow and particle movement, increasing the chances of collisions between particles and between particles and components, thus further improving the pulverization efficiency. Throughout the pulverization process, the material particles undergo multiple collisions, impacts, and frictions, gradually being pulverized into fine particles, completing the pulverization operation and obtaining powder products with the required particle size distribution.

[0040] It is understandable that the main body of the crusher 1 can be made of stainless steel.

[0041] Example 2 In this embodiment, y = 1.5m and x = 0.5m.

[0042] In this embodiment, the main body of the crusher 1 processes 100 kg of material per hour. By designing y to be 1.5 m and x to be 0.5 m, it can be ensured that the material has sufficient residence time and a suitable movement trajectory in the crushing chamber 11, so that the material can fully contact the supersonic airflow and increase the probability and intensity of collisions between particles and between particles and airflow.

[0043] This design also reduces airflow turbulence by more than 20%, making the material's crushing path within the crushing chamber 11 more fixed and forming a regular motion path. This reduces ineffective movement and energy loss, thereby significantly improving crushing efficiency and product particle size uniformity.

[0044] Example 3 In this embodiment, on the horizontal plane of the crushing chamber 11 with x=0.8m, six nozzles 12 are arranged in a circular array on the main body 1 of the crusher. The diameter of the air inlet is 0.1m and α=50°.

[0045] Through the above design, a uniform airflow is formed in the pulverizing chamber 11, which can reduce the standard deviation of velocity distribution to below 15m / s, effectively avoiding the problem of uneven pulverization caused by excessively high or low local airflow velocities.

[0046] Those skilled in the art will understand that although preferred embodiments of the present invention have been described, those skilled in the art, once they learn the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the present invention. Clearly, those skilled in the art can make various alterations and modifications to the present invention without departing from its spirit and scope. Thus, if these modifications and modifications of the present invention fall within the scope of the machine equivalents of the claims of the present invention, the present invention also intends to include these modifications and modifications.

Claims

1. A novel airflow pulverizer, characterized in that, include: Crusher body (1); The crushing chamber (11) is a rotating body formed by the hyperbola L1 rotating around the central axis L2 of the crusher body (1), and is located inside the crusher body (1); Several air inlets are arranged on the main body (1) of the crusher along the tangential direction of the crushing chamber (11); Several nozzles (12) are installed inside each air inlet, corresponding to each air inlet; The feeding component is located above the nozzle (12) and is connected to the crushing chamber (11) for conveying materials; The discharge port (14) is located above the main body of the crusher (1), with the central axis L2 of the crusher body (1) as the center.

2. The novel airflow pulverizer according to claim 1, characterized in that, The expression for hyperbola L1 is: y = a / x, where y is the length of the crushing chamber (11) in m; x is the diameter of the crushing chamber (11) in m; a is a constant; and 2.5 ≤ y / x ≤ 3.

5.

3. The novel airflow pulverizer according to claim 2, characterized in that, y=1.5m, x=0.5m.

4. The novel airflow pulverizer according to claim 3, characterized in that, On the main body (1) of the crusher, there are 6-8 nozzles (12) arranged in a circular array; the angle between the central axis L3 of the nozzle (12) and the central axis L2 of the main body (1) of the crusher is α, 45°≤α≤60°.

5. The novel airflow pulverizer according to claim 4, characterized in that, On the horizontal plane of the crushing chamber (11) with x=0.8m, there are 6 nozzles (12) arranged in a circular array on the main body (1) of the crusher. The diameter of the air inlet is 0.1m and α=50°.

6. The novel airflow pulverizer according to claim 1, characterized in that, The nozzle (12) is a Laval nozzle (12).

7. The novel airflow pulverizer according to claim 1, characterized in that, The feeding device is a screw feeder or a vibrating feeder.

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