Big stone is crushed by rock crusher into proper size, then bucket elevator will take them into hopper. Through vibrating feeder, send them averagely, quantificationally and continuously into grinder mill plant. The grinded powder is raised with the fan airflow and classified by classifier. The fine powder conforms with airflow and enters into cyclone, discharged through the powder discharge valve as production. The air flow is drawn into blower from the upper return air duct of the large cyclone collector, and the above cycle is repeated. The whole airflow system is closed loop and negative pressure conditions.
