Safe production is greater than the sky, and the responsibility for safety is more important than the mountain. At present, the use of jet mills to produce ultra-fine powder is a relatively common method, but there are many safety problems in the use process, which have not attracted enough attention, which is not conducive to the personal health and safety of operators. Therefore, it is necessary to understand its working principle, identify potential safety hazards, and conduct in-depth safety protection and management work.

Jet pulverization technology has the advantages of high strength, regular particles, smooth surface, narrow particle size distribution, less pollution, high purity, pulverization of low melting point and heat-sensitive materials, and is an effective method for ultrafine and ultrafine pulverization. In jet pulverization, it is important to make the airflow reach a considerable speed, so that the material can obtain sufficient energy, and the design of the nozzle, which is the key component required by the airflow, is particularly important.

The quality of the nozzle design determines the overall performance of jet pulverization. The structure design of the nozzle of the jet mill is analyzed and researched. According to the characteristics of the nozzle, the design method of the three-dimensional axisymmetric nozzle is proposed.

Working principle of jet mill

Through the nozzles installed around the crushing chamber, the pressure energy of compressed air is used to form a high-speed airflow trajectory in the crushing chamber. This jet flow causes the powder to be subjected to impact, shearing, compression and other forces, and the powders are intensely generated between each other. Friction, when the external stress is greater than the internal stress of the particle itself, the purpose of crushing can be achieved.

Due to the centrifugal force in the crushing chamber, it can achieve the function of powder classification. According to the working principle of the crushing sample of the jet mill and the actual operating experience, it is found that the main safety problem involved in the sample crushing process is the hazard of dust.