A large amount of powder enters into the mixing chamber through the solid inlet and the atomized liquid enters into the mixing chamber from the liquid inlet. With the high-speed rotating impeller, the powder and liquid droplets are fully mixed in a few seconds. The droplets will evenly adhere to the surface of the powder or be absorbed by the powder. Since both powder and liquid are fed quantitatively, the ratio of powder and liquid droplets shall be strictly controlled. Because residence time in the mixing chamber is very short, the stickiness situation has also been greatly improved.