The main types of airflow mills used in my country's industry are: flat airflow mill, fluidized bed counter-jet airflow mill, circulating tube airflow mill, counter-jet airflow mill, target type Airflow mill. Among these types of jet mills, flat jet mills, fluidized bed spray jet mills, and circulating tube jet mills are most widely used.
Opposite-jet airflow mill
After the material enters the crushing chamber through the spiral feeder, the impact energy of high-speed airflow is sprayed out by several oppositely arranged nozzles, and the rapid expansion of the airflow forms a The collision and friction generated by the suspended boiling of the fluidized bed crush the materials. The coarse and fine mixed powder passes through the turbine classification device set on the top under the driving of negative pressure airflow. The fine powder is forced to pass through the classification device and is captured by the cyclone collector and bag dust collector. The coarse powder is thrown away by gravity and the centrifugal force generated by the high-speed rotating classification device. It moves toward the four walls and settles back into the crushing chamber to continue crushing.
Flat airflow mill
The high-pressure airflow as the kinetic energy of the crushing enters the stable pressure air storage bag on the periphery of the crushing chamber as an airflow distribution station. The airflow is accelerated into a supersonic airflow through the Laval nozzle Then it enters the crushing grinding chamber, and at the same time, the material is accelerated and introduced into the crushing grinding chamber through the Venturi nozzle for simultaneous crushing. Since the Laval nozzle and the crushing chamber are installed at an acute angle, the high-speed jet flow drives the material to circulate in the crushing chamber, causing mutual impact, collision, and friction between the particles and the wall surface of the fixed target plate to cause crushing. The fine particles are driven by the centripetal air flow into the center outlet pipe of the crusher and enter the cyclone separator for collection. The coarse powder is thrown towards the peripheral wall of the crushing chamber under the action of centrifugal force and continues to be crushed.
Circulating tube airflow mill
The raw materials are added to the crushing chamber through a Venturi nozzle, and the high-pressure airflow is sprayed into the racetrack-shaped circulating tube crushing chamber with unequal diameters and curvatures through a set of nozzles. Accelerate the particles so that they impact, collide, and rub against each other to crush them. At the same time, the swirling flow also drives the crushed particles upward along the pipe into the classification area. Under the action of the centrifugal force field in the classification area, the dense material flow is diverted. The fine particles are classified in the inner layer and discharged after being classified by the louver-type inertial classifier. Coarse particles return along the down tube in the outer layer to continue cyclic crushing.
Fluidized bed airflow mill
Jetflow mill (fluidized bed airflow mill) is a machine in which compressed air is accelerated into a supersonic airflow through a Laval nozzle and then injected into the crushing area. The materials are fluidized (the air flow expands to cause fluidized bed suspension boiling and collision with each other), so each particle has the same state of motion. In the crushing zone, the accelerated particles collide and crush each other at the intersection point of each nozzle. The crushed materials are transported to the classification area by the rising airflow, and the fine powder that meets the particle size requirements is screened out by the horizontally arranged classification wheel. The coarse powder that does not meet the particle size requirements is returned to the crushing area to continue crushing. Qualified fine powder enters the high-efficiency cyclone separator with the air flow and is collected. The dust-containing gas is filtered and purified by the dust collector and then discharged into the atmosphere.