Abstract: Handan Coal Preparation Plant has two heavy medium cyclone systems, i.e. the north system and the south system. They are both gravity-fed 3-product cyclones of traditional structure. As part of the technical transformation work, the south system is replaced by a cyclone featuring a novel structural design because the use of the former system would entail high loss of clean coal in both middling and refuse products. Comparison with the north system which remains unchanged shows that after transformation, the south system can operate with a rise of organic efficiency by 3.44 percentage points, a notable drop of probable error, an increase of up-to-standard rate of ash of clean coal by 5.59 percentage points, a decrease of consumption of media solids by 0.11 kg/t, and the overall clean coal yield was expected to increase by 0.61 percentage points. The use of cyclone brings about a favorable economic result for the plant, and also provides a reliable basis for making technical upgrading of the other system.