The air classifier can accurately classify metal powder
The rapid development of 3D printing has been widely used in our real life. The production of metal powder is a very critical part, but it is often overlooked. For high-quality special metals with superior mechanical properties required in the industry, alloy metal powders are showing an increasing trend. Airflow classifier is a common equipment in metal powder processing, and it is also a more important equipment. Only qualified finished metal powders screened by the airflow classifier can be put into application.
The metal powder air classifier is a classifying system composed of a classifier, a dust collector, and an induced draft fan. Under the action of fan suction, the material moves at high speed from the lower end of the classifier to the classification area with the updraft. Under the action of the strong centrifugal force generated by the high-speed rotating classification vortex, the coarse and fine materials are separated, and the fine particles that meet the particle size requirements are classified. The gap between the wheel blades enters the cyclone separator or the dust collector to collect, the coarse particles entrained by the part of the fine particles hit the wall and the speed disappears, and they descend along the cylinder wall to the secondary air outlet. After the strong elutriation of the secondary air, the coarse and fine particles are separated. The particles rise to the classification zone for secondary classification, and the coarse particles fall to the discharge port for discharge.
Equipment performance characteristics of metal powder air classifier:
1. It does not need to be washed with water or water, and it is produced by completely dry method, which can obtain a narrower particle size distribution and non-polluting abrasive powder; one grade can be processed into products of any brand according to the current domestic and foreign standards (such as: national standard W63～W3.5, Japanese standard 240#～3000# and European standard F230/53～F1200/3). The single number finished product rate reaches more than 75%.
2. The classification accuracy is high, the cutting particle size is more accurate, the required speed is lower, and the service life is long.
3. Independent casting bearing seat, never deformed, and long service life.
4. Optimized transmission design, small bearing force and long service life.
5. Unique piping design helps powder flow, helps reduce abrasion, and easy-to-wear parts are easy to replace and handle.
6. The unique frequency conversion feeding system is helpful for the dispersion of materials, can ensure the continuous uniformity and stability of the feeding, and is helpful for the control of product particle size.
7. Unique internal circulation secondary air design, adjustable grading cone gap, greatly reduced air consumption, lower grading energy consumption, and thorough extraction of fine powder.
8. The separation of the flow path helps to slow down the abrasion at the bottom of the classification wheel and is more conducive to the control of large particles.
9. Fully enclosed negative pressure operation, no dust pollution.
10. Good stability, stable production after adjusting the fixed parameters once;
11. In particular, the core competitive advantage of more thorough extraction of fine powder and good stability has been widely recognized by the industry.
12. The whole system adopts automatic control, which can realize one-button start and stop, and the operation is simple and convenient. The connection with the central control can realize remote control.
- General application:
It can classify materials that cannot be classified on ordinary sorting equipment. It is especially suitable for processing products that strictly limit the largest particle size and require a narrow particle size distribution, such as heavy calcium, kaolin, talcum powder, barite powder, copier toner, paint, Mica, graphite, auxin, aluminum hydroxide, etc.
- High-purity applications:
It can classify materials with extremely strict impurity content or materials that are extremely sensitive to iron, while meeting the requirements of particle size and particle size distribution. Typical materials are: fluorescent powder, titanium dioxide, starch, silica gel, aluminum, copper, luminescent powder and various high-purity pigments.
- Abrasive and hard materials:
The application of the vertical eddy current classifier can exceed the subdivision level of hard materials with a Mohs hardness level of seven or more, so that the wear of the equipment is extremely small. The rotating speed of the grading wheel can be adjusted, and the crushing parameters can be optimized. The combination of multiple classifiers can complete narrow-band classification of several particle sizes at one time. Typical products are: diamond, silicon carbide, boron carbide, tungsten carbide, special ceramics, emery and so on.
- Food, health products, medicine:
It can superfinely process the raw materials of medicine, food and health care products. Its low-temperature pulverization, high-purity operation, high processing finish and easy cleaning of the machine are ideal for use in the pharmaceutical, health care and food industries, which not only improves the bioavailability of medicines. And curative effect, and reduce production cost. Typical products are: pollen, hawthorn, shiitake mushroom, pearl powder, stomach medicine, nimodipine, antibiotic medicine, contrast medicine, Ganoderma lucidum, gallnut, fleece-flower root, etc.
Analysis of Principle and Characteristics of Quartz Ultrafine Jet Mill
Quartz sand is an important industrial mineral raw material, widely used in glass, casting, ceramics and refractory materials, metallurgy, construction, chemical industry, plastics, rubber, abrasives and other industries. Quartz sand is a kind of quartz particles produced by crushing quartz stone, which is a difficult raw material to process in non-metallic minerals. The strong representative material in mineral crushing is quartz, which has a density of 2.6g/cm3 and a Mohs hardness of 6.5-7.5, which is a natural high-hardness and wear-resistant material. Quartz sand grinding requires low iron content, good grain shape, concentrated particle size, less fine powder, and no dust flying. It is a relatively difficult raw material to process in non-metallic minerals.
The ultra-fine jet mill is a compressed air that is frozen, filtered and dried, and then forms a supersonic airflow through the nozzles to be injected into the grinding chamber to fluidize the material. The accelerated material merges at the intersection of the jet airflows of several nozzles to produce Violent collision, friction, and shearing can achieve ultra-fine pulverization of particles. The pulverized material is transported to the impeller classification area by the rising airflow. Under the action of the centrifugal force of the grading wheel and the suction force of the fan, the coarse and fine powder are separated. The airflow enters the cyclone collector, the fine dust is collected by the bag filter, and the purified gas is discharged by the induced draft fan.
Features of superfine jet mill:
(1) This machine is the latest combination of fluidized bed and high-precision vertical turbine classifier.
(2) High efficiency: The full use of jet energy greatly improves the crushing efficiency.
(3) Low abrasion: "Fluidized bed + vertical turbine classifier" can process ultra-fine powder with high purity and ultra-narrow, avoiding the abrasion of the crushing part of the "spray + vertical classifier" and "fluidization" Wear of the “bed + horizontal classifier” classification part. Under the same material, the service life of equipment wearing parts is equivalent to 8 times that of similar international products.
(4) High classification accuracy: stable and complete classification flow field and special sealing measures can effectively avoid the leakage of coarse particles. The vertical turbine classifier and the fluidized bed form an internal circulation to ensure the qualified product particle size d97=2 -74µm.
(5) Less over-crushing: The unique classification flow field reduces the gas-solid concentration in the classification zone and avoids over-crushing.
(6) Variable combination structure: It can be used as a machine for two purposes. It can be used as a crushing classifier or a separate classifier.
(7) Fully enclosed negative pressure operation, no dust pollution, dust removal rate above 99.9%.
(8) The equipment is easy to operate and maintain, easy to disassemble and wash, and has low noise.
(9) The equipment has particle shape control technology, which can maintain the material characteristics.
Jet mills are also widely used in ultra-fine grinding of low-temperature, high-purity and high-hardness dry materials such as chemicals, abrasives, ceramics, environmental protection, new materials, new energy, non-metallic minerals, medicine and food, powder metallurgy, battery materials, etc.
The use of jet mills to process APIs is the mainstream of the market
Raw material drug powder generally refers to products with a product particle size of less than 20μm. Airflow pulverization of micropowder is an operation process of pulverizing larger particles or powders into smaller particles or powders. Generally, the product size after pulverization is required to be less than 20μm. Its purpose is to reduce the particle size, increase the specific surface area, and increase the distribution range of the required particle size.
Jet mills are mainly divided into two types: collision type and cyclone type. Its working principle is to use compressed air (or nitrogen) as power, the material is accelerated in the pulverizer for high-speed movement, and the material particles collide with the inner chamber of the pulverizer to achieve pulverization. The main purpose is to change the particle size and Its surface activity and so on. The particle size of the material can be crushed to between 1μm and 100μm.
The characteristics of the API jet mill are:
1. This equipment is made of stainless steel 316 and stainless steel 304.
2. The inside of the equipment is finely polished 0.25-0.5 microns to meet the polishing requirements of different parts.
3. All equipment adopts quick pipe clamp interface connection, which is easy to disassemble and install, and easy to clean.
4. The equipment adopts movable casters, which is easy to move.
5. Except for the feeder, this equipment does not require electricity for other parts, and can be produced only by providing compressed air.
6. The equipment processing capacity is 0.5-30kg/h.
7. The finest pulverization fineness d100<3 microns.
8. It can solve the problems of sticking and blocking of viscous materials and strong static materials.
9. The equipment is airtight, there is almost no loss of raw materials, and the collection rate is high; the equipment has good airtightness, no leakage, and little damage to operators.
10. The equipment has low operating noise. Under normal production conditions, the equipment noise is very low, less than 63dB.
11. The raw materials produced can be directly connected to the packaging bag according to the requirements, which can avoid the leakage caused by the transfer process of the raw materials from the tank to the packaging bag, and avoid the damage to the human body and the leakage loss of the sticky wall of the material.
12. Compared with other equipment, the jet mill has lower energy consumption and smaller nozzle aperture.
13. It can provide a crushing cavity with a very narrow particle size distribution.
14. According to requirements, different Laval nozzles can be provided with different spray angles.
15. The crushing pressure can be up to 1.6Mpa.
16. There is no back-blowing phenomenon, our crushing disc pressure and feeding pressure, no matter which pressure is high, there will be no back-blowing phenomenon.
The jet mill classifier strictly controls the morphology, particle size and purity of the carbon powder
Toner, also called toner, is a powdery substance used to fix images on paper. In response to different needs, the production of toner is developing in the direction of refinement, colorization and high speed. Toner powder manufacturing mainly adopts pulverization method and polymerization method, and the pulverization method is widely used in the carbon powder processing industry. Compared with other crushing equipment, the product morphology, particle size distribution, purity, etc. obtained by using the jet mill has obvious advantages. It is one of the few domestic equipment that can process color consumable powder.
The standard configuration of the jet pulverization and classification production line is a combination of a fluidized bed jet pulverization host and a turbo classifier (an additional classifier will be added when high requirements are required). The particle size distribution is strictly controlled to ensure a qualified collection rate and yield. The complete production line has mature technology, stable equipment performance, constant operating parameters and reliable quality.
Features
- The jet pulverizer classifier can efficiently and accurately process high-quality toner for laser printer copiers.
- The complete and stable flow field established by multiple high-efficiency and high-precision classifiers in series strictly limits the generation of large particles, obtains an excellent particle size distribution and a very narrow particle size range, and can control the particle size of the product within a specific range.
- The control of pulverization strength and the technology of high-efficiency grading ensure a higher yield. The yield of black powder is more than 80%, and the yield of color powder is more than 70%.
- The effective application of particle shape control technology can obtain a better product shape.
- Once the operating parameters of the equipment are adjusted and fixed, the operation is stable, and there is no difference or change in the long-term continuous startup.
- Fully enclosed negative pressure operation, low-temperature crushing, high-purity operation, no dust pollution, system emission <5mg/m3.
- Equipped with a cyclone collector, the separated waste can be reused, reducing production costs.
Laboratory jet mill runs under full negative pressure, no dust pollution
The laboratory jet mill is a kind of small crushing equipment developed and produced for universities, research institutes, and small processing companies. The laboratory jet mill has the characteristics of high crushing accuracy, accurate classification, and the whole machine is small and easy to operate.
The laboratory jet pulverizer is composed of a pulverizing host, a classifier, a cyclone separator, and a pulse dust box. The materials enter the crushing chamber from the feeding hopper, and the materials are blown by high-speed airflow to make them collide and rub each other to be crushed. The distance between the grading knife and the grading disc is adjusted to achieve the required fineness. The crushed material enters the cyclone separator under the action of centrifugal force and the induced draft fan, and then is discharged through the fan induced air, and the dust enters the pulse dust collector, and is recycled after being filtered by an anti-static dust bag. The machine is designed according to the "GMP" standard. The whole machine is made of 304 stainless steel. It runs under full negative pressure, and there is no dust during the crushing process.
The laboratory jet mill also has the following performance advantages:
- It is used for small batch processing in the laboratory, the minimum feeding amount is about 500g;
- The granularity of crushing and classification can be adjusted arbitrarily from D50:1~45μm;
- Frequency conversion control, stable fineness and continuous work;
- Quick installation connection, easy to disassemble, easy to clean, no dead angle;
- The crushing process does not heat up, no impurities are mixed, and the noise is low;
- Small footprint and beautiful appearance;
- Good sealing, no dust, and small loss;
- It can flexibly realize the integration of jet smashing, jet grading, and mechanical smashing;
- The rotor of the horizontal high-efficiency classifier can reach 18,000 rpm;
- The mobile mechanical crusher unit is extremely convenient to disassemble and assemble;
- The mechanical pulverizer can realize full ceramicization;
- It can realize inert gas circulating atmosphere and powder classification of flammable and explosive materials;
- The sintered plate filter and dust removal unit can be selected, and the filter accuracy can reach 0.1μm99.9.
Jet mill achieves a breakthrough in the grinding of lithium battery materials
Lithium iron phosphate is a new type of lithium-ion battery electrode material. The ultrafine jet mill can pulverize lithium iron phosphate to 1-5 microns and achieve precise classification.
The lithium iron phosphate ultra-fine jet pulverization production line is a special production line specially developed for lithium iron phosphate pulverization according to the needs of the manufacturer and the problems encountered in the production and treatment of lithium iron phosphate. This production line is a closed cycle system that uses high-temperature dry nitrogen. , A device for simultaneous ultra-fine grinding and drying of lithium iron phosphate; the sintering system, crushing system, and packaging system for producing lithium iron phosphate are fully enclosed. Lithium iron phosphate is enclosed and transported during the sintering, crushing, packaging and other processes; the crushing system uses high-temperature dry nitrogen as the crushing gas source to dry the lithium iron phosphate instantaneously, and the lithium iron phosphate crushing and drying are carried out at the same time. This system solves the problem of continuous drying of phased products in the production process of lithium iron phosphate, saves energy and reduces production costs.
The new type of lithium iron phosphate ultrafine jet pulverization production line is a dedicated production line system that integrates high-temperature nitrogen protective jet pulverization and drying systems. Using high-temperature dry gas, while ultra-fine grinding of lithium iron phosphate cathode material for lithium batteries, supersonic airflow rotary jet flow field is used to conduct heat and mass transfer and instantaneous drying of the surface water of the material to achieve ultra-fine grinding of lithium iron phosphate. +Integration of trace moisture drying. When the feed moisture is 3000PPM and the feed particle size d50=20-30μm, the finished product particle size d50=0.6-2μm, d100=4-10μm, and the finished product moisture 200-500PPM after the integration of crushing and drying. Taking the production line with an annual output of 3000T as an example, the energy consumption per ton is 650-900 yuan/T, and the nitrogen consumption is 410-600Nm3/h. Compared with the traditional double-cone drying or roller furnace drying and ultra-fine grinding process, it saves 4.5-5.5 million yuan in energy consumption every year. At the same time, the ultra-fine pulverization and drying process realizes a fully closed-circuit air conveying system, which produces no dust pollution throughout the process. This process realizes the effective combination of lithium iron phosphate ultrafine grinding technology and ultrafine particle surface trace moisture control technology, and effectively solves the current problems that restrict the service life and safety of lithium batteries. It is lithium iron phosphate ultrafine powder for lithium battery cathode materials. A major breakthrough in the field of body preparation.
Various types and models of ultra-fine jet mills, classifiers, and crushing production lines are suitable for rare earth, mining and metallurgy, chemical, energy, medicine, feed, food and other industries. Whether the processed materials are ore, rare earths, non-ferrous metals, plastics, medicinal materials, agricultural products, or flammable, explosive, and oxidizable materials, it can meet your requirements on the particle size, output, and energy consumption of the finished product.
Air classifier can classify particles of various shapes
Air classifier is a kind of fine powder screening equipment, it is a kind of non-screen type classification equipment. Compared with screen type, air classifier is more in line with the requirements of today's environmental protection, and can be dust-free and stain-free during processing. And because it has no screen, it can effectively avoid the phenomenon of material blocking and adhesion, and can also ensure the purity of the raw materials.
The airflow classifier can classify spherical, flake, and needle-shaped particles, and can also classify particles of different densities. It has a wide range of applications, covering almost all areas of dry fine powder, such as metal powder, alloy powder, mineral powder, battery materials, ceramic powder, rare earth, etc. The wide application range of the air classifier benefits from its following performance advantages:
- It is suitable for the fine classification of dry micron products. It can classify spherical, flake, and needle-shaped particles, and can also classify particles of different densities.
- The particle size of the classified products can reach D97: 2～45 microns, the product particle size is adjustable, and the variety is extremely convenient to change.
- The classification efficiency (extraction rate) is 60% to 90%, and the classification efficiency of materials with good fluidity is high, otherwise the efficiency is reduced.
- The vertical grading turbine device is adopted, which has low speed, wear resistance and low system power configuration.
- It adopts horizontal grading turbine device with high speed and accurate apex cutting.
- Multi-stage classifiers can be used in series to produce products with multiple particle sizes at the same time.
- It can be used in series with ball mills, vibration mills, Raymond mills and other grinding equipment to form a closed loop.
- The control system adopts program control, the running status is displayed in real time, and the operation is simple and convenient.
- The system operates under negative pressure, and the dust emission does not exceed 40mg/m³, and the equipment noise is not higher than 75dB(A) through the use of silencer measures.
The performance advantages of jet mills can replace most mechanical pulverizers
Due to the widespread nature of industrial production, with the rapid economic development, jet mills have developed rapidly. In the scientific research and development process of powder production, application and equipment manufacturing, new equipment and new products are constantly appearing on the market. Jet mill is one of many crushing equipment.
Jet mill is different from other pulverizers. It is under the action of high-speed airflow, the material is crushed by the impact between the particles of the material, the airflow impacts the material and the impact, friction, and shear of the material and other parts. Therefore, the average particle size of the material after airflow pulverization is fine, the particle size distribution is narrow, the particle surface is smooth, the particle shape is regular, the purity is high, the activity is high, and the dispersibility is good; With compressed air as the power, the adiabatic expansion of the compressed gas at the nozzle will reduce the temperature of the system). And if N2, CO2 and other gases are used, it can be crushed in an inert atmosphere under special occasions.
Jet pulverization can be operated under aseptic conditions; the production process is continuous, the production capacity is large, and the degree of self-control and automation is high. However, the production cycle of crushing equipment such as mechanical impact mills, vibration mills, and stirring mills is often long, resulting in low production efficiency; a large amount of heat is generated when the materials are crushed, which causes the deterioration of heat-sensitive materials; and the wear of the equipment will contaminate the products. . Therefore, these mechanical pulverizers can no longer fully meet people's increasingly high requirements for ultra-fine powder materials. Jet pulverization equipment has a tendency to replace mechanical pulverizers in the production of ultra-fine powder. Since the advent of the jet mill in the 1930s, through the efforts of many researchers, its structure has been continuously updated and the types have continued to increase. Fluidized bed jet mill, target jet mill, supersonic jet mill, etc.
There are many types of ultra-fine jet mills with different structures, and each model has its advantages and disadvantages. In recent years, the crushing equipment has been greatly improved on the basis of the previous, its structure has been continuously improved, and the crushing performance has been continuously improved. In order to meet the higher requirements of the development of information technology, biotechnology and new material technology on the particle size, purity and particle size distribution of powder products, the research of ultrafine jet pulverization technology should focus on the development of the following aspects: To improve and optimize ultra-fine jet mill equipment, develop new equipment, and pay attention to the matching design of pulverization and classification systems; there are not many large-scale equipment. In the above-mentioned ultra-fine jet mill, in comparison, the fluidized bed collision type Jet mill has obvious advantages, so theoretical research should be strengthened to guide the design of crushing equipment; since the biggest disadvantage of jet mill is low energy utilization rate, ways to reduce energy consumption and increase energy utilization rate should be sought.
The particle size of the air classifier can be adjusted freely, with high precision and high efficiency
The particle size distribution of ternary materials will affect the specific surface area, compaction density, pole piece processing performance and electrical performance of the battery. The grinding equipment can only control the particle size of the material, but it cannot control the particle size distribution of the material. If you want to control the particle size distribution of the material, you must use a grading device. The classification of ternary materials is generally followed by the airflow pulverizer with an airflow classification device to directly classify the crushed products. The airflow classifier is related to the quality of the final product of the ternary material.
The classifier, cyclone separator, dust collector, and induced draft fan form a set of classification system. Under the action of fan suction, the material moves to the classification area at high speed from the lower inlet of the classifier along with the updraft. Under the strong centrifugal force generated by the high-speed rotating classification turbine, the coarse and fine materials are separated, and the fine particles that meet the particle size requirements are classified. The gap between the wheel blades enters the cyclone separator or the dust collector to collect, the coarse particles entrained by the part of the fine particles hit the wall and the speed disappears, and they descend along the cylinder wall to the secondary air outlet. After the strong elutriation of the secondary air, the coarse and fine particles are separated. The particles rise to the classification zone for secondary classification, and the coarse particles fall to the discharge port for discharge.
The structural characteristics of the ternary material air classifier:
(1) Under the action of the high-speed rotating impeller, the pressure of the gas flowing through the impeller increases. After the high-pressure airflow flows out of the impeller, it passes through the injection fine-particle ring. Because the blades of the rotating guide vane are designed to be curved, the cross-sectional area of the inlet is Larger, the outlet cross-sectional area is small, so the airflow pressure at the outlet decreases, the speed increases, and it flows out in a rotating direction, which is conducive to classification.
(2) The grading point adjustment mechanism is equipped with three adjustment rods, and a chain is used to keep it moving in sync. The adjustment lever moves upward. The fine powder increases; when the adjusting lever moves down, the fine powder decreases. The classification point can be continuously adjusted steplessly. The particle size of the air classifier with better performance is steplessly adjustable. The particle size of the classified product can reach D97: 3 ~ 150 microns, which is suitable for the fine classification of dry micron products.
(3) Control ring setting: The control ring is to ensure that a suitable cross section is formed between the control ring and the injection fine particle ring, and the flow rate of the control air flow is stable.
(4) The residual air vent will inevitably bring in excess gas from the dry materials, and the temperature in the classification room is higher, and the air will expand. Therefore, a residual air vent is designed to maintain a stable and balanced air flow in the classification room.
The performance of lithium iron phosphate jet mill meets user needs
The material is fed into the crushing chamber between the machine body and the splitter ring by the screw feeder through the feed port, and is driven by the high-speed rotating hammer disk in the room, thrown to the stator gear ring fixed on the machine body, and is impacted and crushed. Under the pulling force of the negative pressure airflow, the crushed materials have small particles that overcome the weight of the powder particles and make them exceed the split ring and enter the classification chamber between the split ring and the grading impeller. The grading impeller is composed of blades, which are driven to rotate by a motor to generate an internal circulating air flow. When the powder passes through the gap between the grading impeller blades, it is subjected to three forces at the same time, namely the centrifugal force, gravity and the pulling force generated by the negative pressure airflow. Only the fine particles with negative pressure greater than the centrifugal force and gravity can pass the classification smoothly. The impeller enters the cyclone separator. Large powder particles are thrown to the shunt ring due to their large centrifugal force and return to the crushing chamber to be crushed again.
Technical characteristics of lithium iron phosphate jet mill
- The grading adopts horizontal grading wheel, which has more accurate cutting accuracy and higher grading efficiency than vertical grading wheel.
- The use of high-speed, small grading wheels to ensure grading accuracy, which is more than twice as accurate as the use of large wheels and low-speed jet mills.
- After a special flow field design and high-precision mechanical processing, the energy consumption is reduced by 30% compared with the disc and cyclone jet mills under the same output.
- Production serialization: 2～5000 kg/h; high fineness: d97=1～180μm;
- Good particle shape, narrow particle size distribution range;
- Program control, imported components; good man-machine interface, easy to operate;
- Infinitely adjustable, stable operation, thorough cleaning, easy to change varieties;
- Wide application range: various soft and hard materials with Mohs hardness below 9.5;
- It has a wear-resistant protection device, and the life of the silicon carbide graded wheel is 1000H.