Motor runs under the condition that speed reducer drives Nether millstone. The materials fall into the center of device through lock air feeder, and hot air comes into mill through air inlet under the function of centrifugal force, the materials when they come by the annular chute. The grinded materials will be taken up by air circulation and the bigger powder will fall down for regrinding. Qualified powders will be collected by collecting device as to be final product. Materials containing water will be dried when they contact with the hot air. Different humidify materials can be dried to the requirement through adjusting the temperature of hot air. Adjusting the separator can get the required fineness powders.