The gas-solids two-phase flow in the superfine classifier with two different feeding types was studied by numerical simulation.The pressure difference

air velocity and solids concentration distribution were analyzed.The performance superfine classifier with two feeding types was studied by experiments

and the characteristic particle size and size distribution of fine powder of under and upper feeding type were compared and analyzed.The results showed that compared with the under feeding type

the pressure drop between inlet and outlet of the superfine classifier of the upper feeding type was bigger due to adding the mechanical spreading plate.For the upper feeding type

the tangential and radial velocities of cylindrical surface along the rotor were distributed more uniformly

which helped to reduce the fluctuation of classification size and obtain fine powder with narrow particle size distribution.Particle concentration was distributed uniformly with the upper feeding type

but was affected heavily by rotor speed.According to the experiment

both under feeding and upper feeding types could obtain good classification performance.After classification

the size of fine powder was small

with narrow distribution

mainly in the range of 1-30 μm.The percentage of particle less than 30 μm of fine powder was above 90%.The study results could provide guidance to designing the feeding type and optimizing the geometry of the superfine classifier.