PURPOSE: To prevent the clogging of a discharge port due to a solid by inserting a liquid supply pipe in a rotatable main body casing in a coaxial state and arranging the conc. slip discharge pipe communicating with the flow passage formed to the bottom part of the main body casing.

CONSTITUTION: A liquid supply pipe 13 is inserted in the upper end of a main body casing 11 formed in a freely rotatable manner in a coaxial state to form a clarified liquid discharge port 12. The concn. slip discharge pipe 15 communicating with the conc. slip flow passage 22 demarcated by a partition plate 21 is also inserted in the lower end of the main body casing 11. When a suspension is supplied in the main body casing 11 from the liquid supply pipe 13, the suspension is separated into a clarified liquid and conc. slip 27 by the centrifugal force due to the rotation of separation plates 17. The clarified liquid 26 is discharged to the outside from the clarified liquid emitting port 12 and the concn. slip 27 is extruded to the flow passage 22 and passes through the emitting pipe 15 to be discharged from a conc. slip emitting port 16 through a discharge pipe 24. By this method, the conc. slip continuously flows without being stagnated in the flow passage and the clogging of the discharge port due to a solid is prevented.