Abstract: An introduction is made in the paper of the structure,working principle and technical features of the PAD gravity-flow type flotation pulp preprocessor as well as the result of its application at a coal preparation plant in Xinjiang Mining Area,Linfeng,Shanci Province.Under the conditions of treating a raw coal with the same property and basically identical product indices,as compared with the impelleragitated type of pulp processor,the use of the gravity-flow version can lead to an increase of flotation perfection index by 1.43 percentage points,a drop of the cost of agents per ton of raw coal treated by 48.53 percentage points and a save of power by 25 000 k W·h per year,effectively reducing,as a result,the operating cost of the plant.