Abstract: To solve the problems of poor reliability and difficult to control in lump raw coal separation system and bad separation result of small coal in Tianzhuang coal preparation plant,the coarse slime separation process added into the original three stage separation process,so formed the four stage separation process which consisted of inclined lifting wheel separating lump coal,the dense medium cyclone separation small coal,the teetered bed separator separating coarse slime and the slurry separation by flotation.With the utilization of the four stage separation process,the clean coal yield steadily increased and medium consumption dramatically decreased in Tianzhuang coal preparation plant.