Inert gas shielding jet milling system

Abstract

The utility model discloses an inert gas shielding air jet pulverization system, which relates to the technical field of air jet pulverization and comprises a raw material conveying system, a feeding control system for controlling feeding speed, a charging control system for controlling material conveying speed and an air source device for controlling gas medium circulation. The crushing system is used for crushing particles, the grader is used for screening the crushed material particles, the unloading and packaging system is used for packaging the material particles, the pulse bag type dust collector is used for separating materials from gas media, and the gas compressor is used for recovering inert gas. The device further comprises an electric control system used for controlling the system, the materials are driven by inert gas to collide at a high speed to achieve the crushing effect, the materials collide and are crushed under the driving of gas flow, media are not brought in, meanwhile, the materials are located in the inert gas during crushing, and therefore the materials cannot be polluted in the crushing process.

Description

Technical Field

[0001] This utility model relates to the field of airflow pulverization technology, specifically an inert gas-protected airflow pulverization system. Background Technology

[0002] Airflow pulverizers and classifiers use airflow to pulverize materials. The materials enter the pulverizer through the feed port and are pulverized by collisions and friction in the middle of the pulverizing chamber under the influence of the airflow. Meanwhile, the compressed air is filtered and dried and then injected into the pulverizing chamber at high speed through a Laval nozzle. At the intersection of multiple high-pressure airflows, the materials are repeatedly pulverized by collisions, friction, and shearing. The pulverized materials are then moved to the classification zone by the upward airflow under the suction of the fan. Under the strong centrifugal force generated by the high-speed rotating classification turbine, the coarse and fine materials are separated.

[0003] Traditional classifiers can control particle size through labyrinth control, but due to processing precision and other reasons, they are often not ideal for controlling large particles, especially for particles larger than 10 micrometers. These particles can easily enter the finished product through the gaps in the labyrinth, resulting in unqualified finished products.

[0004] Meanwhile, the production of battery-grade lithium hydroxide raw materials cannot be separated from the crushing process. Due to the special properties of lithium hydroxide, it is necessary to pay attention to the strong alkalinity of the material and prevent the absorption of carbon dioxide during the processing. In addition, lithium hydroxide monohydrate contains water of crystallization, so the powder requires extremely high purity, and the powder has extremely poor flowability. Therefore, ordinary crushing equipment cannot meet the production requirements. Utility Model Content

[0005] To address the aforementioned technical problems, this utility model proposes the following technical solution:

[0006] An inert gas-protected airflow pulverizing system includes a raw material conveying system, a feeding control system for controlling the feeding speed, a feeding control system for controlling the material conveying speed, an air source device for controlling the circulation of the gas medium, a pulverizing system for crushing particles, a classifier for screening the crushed material particles, a packaging and unloading system for packaging the material particles, a pulse bag filter for separating the material from the gas medium, a gas compressor for recovering the inert gas, and an electrical control system for controlling the system.

[0007] Furthermore, the pulverizing system includes a pulverizing chamber, a supersonic nozzle, an air source distribution chamber, and a high-pressure hose. One end of the high-pressure hose is connected to the air source distribution chamber, and the other end of the high-pressure hose is connected to the pulverizing chamber. A supersonic nozzle is provided at the connection between the high-pressure hose and the pulverizing chamber. The air source distribution chamber is connected to an air source device through a pipeline.

[0008] Furthermore, the feeding control system comprises a star-shaped feeding valve, a level gauge, and a feeding hopper. The continuous and uniform feeding speed is controlled by adjusting the star-shaped feeding valve, while the level gauge reflects the material height in the feeding hopper. The feeding hopper is connected to a buffer hopper.

[0009] Furthermore, the classifier includes a classifier motor, a classifier head, a classifier cylinder, a high-precision turbine, a classifier wheel, and a frequency converter. The frequency converter adjusts the rotation speed of the classifier wheel to control the particle size of the material; the higher the rotation speed, the finer the material after classification.

[0010] Furthermore, the pulse bag filter includes a bag collection device, a pulse cleaning device, and a pneumatic control device, wherein the pulse filter bag in the bag collection device is made of PTFE material.

[0011] Furthermore, the gas source device includes an air compressor for compressed air or inert gas, a precision filter, a refrigerated dryer for reducing the temperature of the compressed gas and removing moisture, a precision filter between the air compressor and the refrigerated dryer for filtering the gas, and the gas outlet end of the refrigerated dryer is connected to the gas source distribution chamber in the pulverizing system.

[0012] Furthermore, the gas source device also includes a nitrogen compressor, a nitrogen generator, and a gas storage tank, with the nitrogen compressor connected to the nitrogen generator via a pipeline.

[0013] The beneficial effects of this utility model are as follows: (1) This device achieves the crushing effect by driving the material to collide at high speed with inert gas. The material is crushed by collision under the drive of the airflow without introducing the medium. At the same time, the material is in an inert gas during crushing, so the material will not be contaminated during the crushing process; (2) By connecting the classifier host to the crushing system, this device can complete the two processes of material crushing and powder classification at the same time. At the same time, the speed of the classifier impeller and the suction volume can be frequency-controlled to adjust the fineness of crushing without stopping the machine; (3) This device can be used to crush materials with a Mohs hardness of 7 or above by driving the material to collide at high speed with the airflow. It can also minimize wear and extend the life of the device; (4) Since the material is crushed in the state of gas adiabatic expansion, the temperature inside the crushing chamber is at room temperature or low temperature and the temperature will not rise. Therefore, the system can be used for crushing heat-sensitive materials and can be used for special crushing work. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0015] Figure 2 This is a schematic diagram of the manual butterfly valve structure of this utility model.

[0016] Figure 3 This is a schematic diagram of the crushing chamber structure of this utility model.

[0017] Attached reference numerals: 1-Air compressor; 2-Refrigerated dryer; 3-Precision filter; 4-Main pneumatic ball valve; 5-Main digital pressure gauge; 6-Finished product silo; 7-Mixing chamber; 8-Feeder; 9-Pneumatic butterfly valve; 10-Pulse bag filter; 11-Nitrogen compressor; 12-Nitrogen generator; 13-Air storage tank; 14-Auxiliary pneumatic ball valve; 15-Auxiliary digital pressure gauge; 16-Manual butterfly valve; 17-Grinding chamber; 18-High-pressure hose; 19-Grinding system; 20-Classifier; 21-Star feeder; 22-Level gauge; 23-Feeding silo; 24-Buffer silo; 25-High-pressure blower; 26-Remote discharge valve. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0019] like Figure 1 and Figure 2 As shown, an inert gas protective airflow pulverizing system 19 includes a raw material conveying system, a feeding control system for controlling the feeding speed, a feeding control system for controlling the material conveying speed, an air source device for controlling the circulation of the gas medium, a pulverizing system 19 for crushing particles, a classifier 20 for screening the crushed material particles, a unloading and packaging system for packaging the material particles, a pulse bag dust collector for separating the material from the gas medium, a gas air compressor 1 for recovering the inert gas, and an electrical control system for controlling the system.

[0020] like Figure 1 and Figure 2 As shown, the raw material conveying system consists of a high-pressure blower 25, a buffer chamber 24, four polymer filter cartridges, a level gauge 22 (divided into a high level gauge and a low level gauge), a remote discharge valve 26, etc. The high-pressure blower 25 generates negative pressure in the buffer chamber 24, allowing the material to enter the buffer chamber 24 through the material conveying pipe.

[0021] like Figure 1 and Figure 2 As shown, the feeding control system comprises a star-shaped feeding valve 21, a level gauge 22, and a feeding bin 23. The continuous and uniform feeding speed is controlled by adjusting the star-shaped feeding valve 21, while the level gauge 22 reflects the material height in the feeding bin 23. The feeding bin 23 is connected to the buffer bin 24.

[0022] like Figure 1 and Figure 2As shown, the classifier 20 includes a classifier motor, a classifier head, a classifier cylinder, a high-precision turbine, a classifying wheel, and a frequency converter. The frequency converter adjusts the rotation speed of the classifying wheel to control the particle size of the material. The higher the rotation speed, the finer the material after classification; the lower the rotation speed, the coarser the particle size. The classifying wheel of the classifier 20 is adjusted by the frequency converter. The classifier 20 is also designed with protection measures such as undervoltage protection, overcurrent protection, material level control, operating status monitoring, and alarm system to protect the classifier 20. In addition, the classifier 20 in this application can also work using the technical solutions adopted in patents with application numbers CN201920611883.8 or CN201721536044.1.

[0023] like Figures 1 to 3 As shown, the pulverizing system 19 includes a pulverizing chamber 17, a supersonic nozzle, an air source distribution chamber, and a high-pressure hose 18. One end of the high-pressure hose 18 is connected to the air source distribution chamber, and the other end is connected to the pulverizing chamber 17. A supersonic nozzle is installed at the connection between the high-pressure hose 18 and the pulverizing chamber 17. Multiple high-pressure hoses 18 and supersonic nozzles are evenly distributed within the pulverizing chamber 17. The air source distribution chamber is connected to an air source device via a pipe. The end of the pulverizing chamber 17 furthest from the air source distribution chamber is connected to the classifier 20. A handpiece is installed at the end of the pulverizing chamber 17 furthest from the separator. The butterfly valve 16 is used to clean the airflow mill chamber. Inert gas enters the gas source distribution chamber and then enters the high-pressure hose 18. After that, the supersonic jet ejected through the supersonic nozzle carries the material in the crushing chamber and accelerates it. At the center point of convergence, the material collides, impacts, and rubs against each other, achieving the effect of crushing the particles. The crushed particles and inert gas then enter the classifier 20. Its crushing system 19 can work using the technical solution adopted in the patent application number: CN202223127812.1. In specific applications, it is necessary to replace the steam with nitrogen and change the materials involved in this technical solution.

[0024] like Figure 1 and Figure 2As shown, the pulse bag filter 10 includes a bag collection device, a pulse cleaning device, and a pneumatic control device. The pulse filter bags in the bag collection device are made of PTFE material. The volume, time, and interval of the pulse air in the bag collection system are controlled by a pulse solenoid valve and a PLC. The material outlet of the classifier 20 is located on one side of the bag collection device. The material after being screened by the classifier 20 enters the pulse bag filter 10. When the inert gas here is filtered by the bag collection device, the filtered inert gas will return to the air source device through the pipeline. The material particles intercepted by the pulse filter bags in the bag collection device will remain in the pulse bag filter 10. Then, the pulse cleaning device will make the material particles fall to the bottom of the pulse bag filter 10. The pulse cleaning device is controlled by a pneumatic control device.

[0025] like Figure 1 and Figure 2 As shown, the unloading and packaging system includes a finished product silo 6, a uniform speed feeder 8, a mixing chamber 7, and a feeder 8. The finished product silo 6 is connected to a pulse bag filter 10. A pneumatic butterfly valve 9 is installed in the connecting pipe between the finished product silo 6 and the pulse bag filter 10 to control the opening and closing of the pipe. A mixer and a vibrating hammer are installed in the finished product silo 6 to prevent material accumulation. The bottom of the finished product silo 6 is connected to the mixing chamber 7. The uniform speed feeder 8 is installed in the connecting pipe between the finished product silo 6 and the mixing chamber 7 to control the falling speed of the material particles. A mixing device is installed in the mixing chamber 7 to accelerate the falling of the material. The feeder 8 is located at the bottom of the mixing chamber 7, and the feeding device can be a screw conveyor or a conveyor belt.

[0026] like Figure 1 and Figure 2 As shown, the electrical control system consists of a PLC and a touch screen, and a one-button start and stop button is set next to the touch screen to make the equipment more intelligent and the operation of the complete set of equipment simpler.

[0027] like Figure 1 As shown, the air source device includes an air compressor 1 for compressed air or inert gas, a precision filter 3, a refrigerated dryer 2 for reducing the temperature of the compressed gas and removing moisture, and a precision filter 3 is installed between the air compressor 1 and the refrigerated dryer 2 to filter the gas. The gas outlet end of the refrigerated dryer 2 is connected to the air source distribution chamber in the pulverizing system 19. Two precision filters 3 are installed in series on the pipeline between the refrigerated dryer 2 and the pulverizing system 19. At the same time, a pneumatic ball valve and a digital pressure gauge are also installed on the pipeline between the refrigerated dryer 2 and the pulverizing system 19. When the high-pressure gas flows from the refrigerated dryer 2 to the pulverizing system 19, it will pass through the precision filter 3, the pneumatic ball valve, and the digital pressure gauge in sequence, and finally the high-pressure gas enters the pulverizing system 19. This pipeline mainly provides high-pressure gas for the pulverizing system 19.

[0028] like Figure 1 As shown, the gas source device also includes a nitrogen compressor 11, a nitrogen generator 12, and a gas storage tank. The nitrogen compressor 11 is connected to the nitrogen generator 12 through a pipeline. A precision filter 3 is installed on the pipeline between the nitrogen compressor 11 and the nitrogen generator 12. The nitrogen generator 12 is connected to the gas storage tank through a pipeline. The gas storage tank is connected to the pulverizing system 19. When the pulverizing system 19 is working, nitrogen is also introduced into the pulverizing system 19 as an inert protective gas to prevent the material from oxidizing or exploding.

[0029] When this device is working, high-purity nitrogen is first continuously injected into the entire system to replace the air in the system until the entire system reaches the value set by the oxygen detector. Then, the star-shaped feeding valve 21 in the feeding control system will be automatically activated, allowing the raw materials in the feeding bin 23 to be evenly added into the crushing chamber 17 in the crushing system 19. The compressed nitrogen is then injected into the crushing chamber 17 at high speed through a specially configured supersonic nozzle, causing the material to accelerate in the supersonic jet flow and repeatedly impact and collide at the nozzle intersection to achieve the crushing effect. The crushed material rises with the airflow and enters the classifier 20. When the classifier wheel rotates at high speed, the particles are subjected to both the centrifugal force generated by the classifier wheel and the centripetal force generated by the viscosity of the rising airflow. That is, coarse particles that are larger than the required classification particle size cannot enter the inner cavity of the classifier wheel and return to the crushing chamber to continue to be crushed. Fine particles that meet the requirements enter the high-precision turbine. Afterward, the fine particles are collected by the pulse bag filter in the pulse bag dust collector 10 with the airflow. The nitrogen in the process is filtered by the precision filter 3 and returned to the air compressor 1 intake port, compressed again and recycled.

[0030] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the scope of protection of the present utility model.

Claims

1. An inert gas-protected airflow pulverizing system, characterized in that: It includes a raw material conveying system, a feeding control system for controlling the feeding speed, a feeding control system for controlling the material conveying speed, an air source device for controlling the circulation of gas medium, a crushing system (19) for crushing particles, a classifier (20) for screening the crushed material particles, a packaging system for unloading and packaging the material particles, a pulse bag dust collector (10) for separating the material from the gas medium, a gas air compressor (1) for recovering inert gas, and an electrical control system for controlling the system. The pulverizing system (19) includes a pulverizing chamber (17), a supersonic nozzle, an air source distribution chamber, and a high-pressure hose (18). One end of the high-pressure hose (18) is connected to the air source distribution chamber, and the other end of the high-pressure hose (18) is connected to the pulverizing chamber (17). A supersonic nozzle is provided at the connection between the high-pressure hose (18) and the pulverizing chamber (17). The air source distribution chamber is connected to an air source device through a pipe.

2. The inert gas protective airflow pulverizing system according to claim 1, characterized in that: The feeding control system consists of a star-shaped feeding valve (21), a level gauge (22), and a feeding bin (23). The continuous and uniform speed control of the feeding is achieved by adjusting the star-shaped feeding valve (21), while the level gauge (22) can reflect the material height in the feeding bin (23). The feeding bin (23) is connected to the buffer bin (24).

3. The inert gas-protected airflow pulverizing system according to claim 1, characterized in that: The classifier (20) includes a classifier motor, a classifier head, a classifier cylinder, a high-precision turbine, a classifier wheel, and a frequency converter. The frequency converter adjusts the rotation speed of the classifier wheel to control the particle size of the material. The higher the rotation speed, the finer the material after classification.

4. The inert gas protective airflow pulverizing system according to claim 1, characterized in that: The pulse bag filter (10) includes a bag collection device, a pulse cleaning device and a pneumatic control device. The pulse filter bag in the bag collection device is made of PTFE material.

5. The inert gas protective airflow pulverizing system according to claim 1, characterized in that: The air source device includes an air compressor (1) for compressed air or inert gas, a precision filter (3), a refrigerated dryer (2) for reducing the temperature of compressed gas and removing moisture, and a precision filter (3) is provided between the air compressor (1) and the refrigerated dryer (2) to filter the gas. The gas outlet end of the refrigerated dryer (2) is connected to the air source distribution chamber in the pulverizing system (19).

6. The inert gas-protected airflow pulverizing system according to claim 5, characterized in that: The gas source device also includes a nitrogen compressor (11), a nitrogen generator (12), and a gas storage tank. The nitrogen compressor (11) is connected to the nitrogen generator (12) through a pipeline.

Images