Application of air flow pulverizer in the production of silicon carbide powder

The production principle of the air flow crusher is to crush the object by the impact of high-speed air flow The crushing forms are mainly collision type, target type, fluidized bed type and so on Widely used in chemical, mineral, metallurgy, abrasive, ceramics, refractory, medicine, pesticide, food, health products, new materials and other industries Compared with the ordinary mechanical ultra-fine pulverization, the air flow pulverization can pulverize the product very fine, and the particle size distribution range is narrow, that is, the particle size is more uniform Because the gas expands at the nozzle and can cool down, there is no heat associated with the pulverizing process, so the pulverizing temperature rise is very low This characteristic is very important for the ultrafine grinding of materials with low melting point and heat sensitivity Experts said that the air flow comminution technology is an advanced comminution technology, which is just in the beginning of the research on the fine processing of traditional Chinese medicine, and there are many problems Air flow comminution and classification technology is an ultra-fine comminution technology developed rapidly in recent years It has been widely used in the preparation of medicine, chemical raw materials and special powders due to its advantages of large comminution intensity, fine comminution particle size, narrow distribution and small product pollution The application of air flow comminution and classification in the production of silicon carbide powder (1) the principle of air flow comminution is that under the action of high-speed air flow, particles are crushed by impact, collision, friction and shear between particles or between particles and targets Air flow comminution has the following characteristics: ① high speed air flow will produce high speed to particles, and the impact strength of particles is large, and ultrafine powder of micron or even submicron level can be obtained; ② the purity of particle products is high, and the pollution is small; ③ the particle size distribution of the products is narrow, the particle morphology is smooth, and the particle dispersion is good; ④ Because the temperature of throttling effect will decrease, the air flow from the nozzle can be used to crush heat sensitive materials (2) Air flow classification Principle of air flow classification: under the action of fan suction, materials move to the classification area at high speed from the lower inlet of the classifier along with the rising air flow Under the strong centrifugal force generated by the high-speed rotating classification turbine, the coarse and fine materials are separated The fine particles that meet the requirements of particle size enter the cyclone separator or dust collector through the clearance of the classification wheel blades, and some of the fine particles in the coarse particles collide with the wall After that, the speed disappears and drops down to the secondary air outlet along the cylinder wall Through the strong washing effect of the secondary air, the coarse and fine particles are separated, the fine particles rise to the secondary classification in the classification area, and the coarse particles fall to the discharge port for discharge What are the important factors that should be taken into consideration when selecting the ultra micro pulverizer of traditional Chinese medicine?