Abstract: In view of the importance of the prewetting of feed coal before its separation, a more efficient wetting mode using toothed mixing plates plus swirl jetting is developed through optimum selection of wetting liquid and comparative analysis of different wetting methods, and by reference to the practical coal preparation plant engineering experience. The use of this method can ensure thorough mixing of feed coal and qualified medium suspension and provide stable density field and centrifugal force field, thus creating a favorable condition for high-precision separation of coal.