Patent ID: 8021289

Claim:
A decanter centrifuge for processing a combined liquid and solid material to separate the liquid from the solid material, the centrifuge comprising: a drive housing having an exterior wall and an interior surface bounding a contained volume within the housing and means to drive the centrifuge, said exterior wall including an end wall; a discharge housing mounted to the drive housing, said discharge housing having an exterior wall including a front wall, a peripheral wall disposed between the front wall and the exterior wall of the drive housing, and an interior surface bounding a contained volume within the housing; a bowl and scroll assembly mounted in the discharge housing to rotate about an axis of rotation, said bowl and scroll assembly having an outer wall cooperating with the peripheral wall to form an enclosure therebetween, said enclosure receiving liquid that is separated from the solid material, the peripheral wall of said discharge housing cooperating with the end wall of said drive housing to form a cavity therebetween; a first non-contacting seal means for separating said enclosure from said cavity, thereby inhibiting a flow of liquid between said enclosure and said cavity; a second non-contacting seal means for separating said cavity from the contained volume within the drive housing, thereby inhibiting a flow of fluid between said contained volume and said cavity; and means connected to the discharge housing for injecting a fluid into the first non-contacting seal means between said discharge housing and said bowl and scroll assembly for cleaning said non-contacting seal means; wherein there are no metal-to-metal contact areas within the interior of the bowl and scroll assembly, and the outer wall of the bowl and scroll assembly comprises a plurality of drain ports located in the rear wall section of the bowl to allow essentially all liquid to drain from the bowl and scroll assembly.