Abstract: In order to solve the problems of poor separation caused by hydraulic moving sieve jig for raw coal,including high content of coal in reject,poor separation of raw coal easy degradation in water etc.,dense medium vessel is employed instead of the jig. The application shows that the content of coal in reject is reduced to below 0. 6%,and then the content of reject in lump clean coal keeps in 0. 75%,which improve clean coal quality.