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.