Patent ID: 7140494

Claim:
A centrifugal separator ( 10 , 10 A, 10 B) which comprises a screw conveyor ( 40 ) inside of a bowl ( 20 ), supports them so as to be relatively rotatable, separates the object to be treated from a feed stock supplied to the inside of said bowl ( 20 ), and carries out cleaning and deliquidization of said object to be treated with a screen part ( 30 ) provided along the inner circumferential surface at one end of the bowl ( 20 ), a hub ( 41 ) of said screw conveyor ( 40 ) having a cleaning liquid receiving part ( 43 ) for receiving the cleaning liquid supplied to the inside of the hub ( 41 ) and a cleaning nozzle ( 45 ) which jet spouts the cleaning liquid from the inside of the cleaning liquid receiving part ( 43 ) toward said screen part ( 30 ), wherein a liquid conduction part for jet spouting at least a part of the cleaning liquid directly toward the residual layer crystals formed in the clearance between the outer circumferential edge of the flight ( 42 ) of said screw conveyor ( 40 ) and the inner circumferential surface of said screen part ( 30 ) is provided; and the tip of at least a part of the cleaning liquid conduction part is located within 10 mm from the inner surface of the screen part ( 30 ).