Patent ID: 6258282
Filing Date: 2001-07-10
Classification: B01D,D21F

Abstract:
A rotating filter system for filtration of a flowing substance, comprising:a container containing a liquid so that the liquid fills the container up to a liquid level;a rotor having a filter element attached thereto, the rotor being rotatable in a rotational direction;a filtrate discharge device in operative engagement with the rotor for discharging filtrate having passed through the filter element, the filtrate discharge device comprising a disc having first, second and third openings defined therein, the first and second openings being in fluid communication with a prefiltrate arrangement for discharging a cloudy filtrate and the third opening being in fluid communication with a clear filtrate arrangement for discharging a clear filtrate, the disc, the prefiltrate arrangement and the clear filtrate arrangement being disposed below the liquid level;the prefiltrate arrangement and the clear filtrate arrangement being disposed so that the filter element, during rotation of the rotor, passes a first filtration region (FF), formed by the prefiltrate arrangement, and then reaches a second filtration region (KF) formed by the clear filtrate arrangement, the second filtration region (KF) being disposed downstream of the first filtration region (FF), the clear filtrate arrangement comprising vacuum means for applying a vacuum in the second filtration region (KF) to promote a clear filtrate discharge; andthe prefiltrate arrangement having a first means for establishing, in the first filtration region (FF), a first filtration zone (FF1) and a second means for establishing a second filtration zone (FF2), the first filtration zone (FF1) having a first pressure and the second filtration zone (FF2) having a second pressure that is lower than the first pressure, the second filtration zone (FF2) being disposed downstream of the first filtration zone (FF1) in the rotational direction of the rotor, the second filtration zone (FF2) being disposed upstream from the second filtration region (KF).