After the material is put into the main machine by the feeding system, the coarse and fine powder is separated under the action of strong grading vortex force. Reaching the particle size requirements of fine powder through the horizontal classification wheel into the fine powder collection system. Coarse powder and a small amount of agglomerated fine powder are lowered to the secondary air inlet, where the coarse powder disperser generates spiral centrifugal updraft to wash the material strongly, and the coarse and fine powder are separated. Fine powder with the updraft into the classification area; Coarse powder down to a inlet air again to accept a strong air inlet flow washing, pure coarse powder through the main motor discharge valve discharge.