After being crushed, material are carried into comminuting chamber by feeding system, the material will be impacted, abrasivesed, cutted,compressed among the high speed rotating parts and grains to realize the superfine grinding. The ground material will be transported to the classifying- sections by the updraft airflow and the coarse particles and fine powders will be separated by centrifugal force of classifing wheels and draft fan. The unqualified powders will be returned to the grinding chamber . The qualified powders will enter the cyclone and the bag collector for collection. The purified gas will be discharged from the fan.