Abstract: The heavy medium separation system originally used by Lvjiatuo Mine Coal Preparation Plant was complicated in process flowsheet and low in separation efficiency, severely restricting the normal operation of the plant. To deal with the situation, work is made on technical transformation of the system through the use of the S-3GHMC1100/910/660 super H.M. cyclones as the primary separation equipment to wash unsized and undislimed raw coal. As demonstrated by test with a stand-alone cyclone, for washing the 200~0.5 mm raw coal, the E values of the cyclone′s first and second stages are 0.023 g/cm³ and 0.031 g/cm³, respectively, and the cyclone can wash down to a lower size limit of 0.25 mm. Through technical transformation, a remarkably economic result is obtained as evidenced by the simplification of heavy medium separation process, improved separation efficiency and the rise of yield of total clean coal by 1.78 percentage point. The application of the super cyclone provides a reference for plants to make similar upgrading.