Patent ID: 7473376
Filing Date: 2009-01-06
Classification: B01D,C01F,C22B,Y02P

Abstract:
1. Apparatus for separating components of slurries by gravity settling thereby forming a thickened slurry and a clarified liquid, comprising a vessel for decanting a volume of slurry, said vessel having a top and an interior formed by a side wall and a bottom wall for holding said slurry, a slurry inlet, an outlet for the clarified liquid near the top of the vessel, a raking device extending into said interior of said vessel and operable to form a raked region within said vessel where said thickened slurry is formed, and a slurry withdrawal apparatus beneath said raked region for removal of said thickened slurry from the vessel at or near the bottom wall thereof; said slurry withdrawal apparatus comprising an elongated, rotatable, open-spiral-shaped element extending or extendable for a distance into said vessel through an opening near the bottom wall of the vessel, said open spiral-shaped element being in direct and unconfined communication with said interior of the vessel over a maiority of said distance when said element is fully extending into said interior of said vessel, and a drive mechanism for said open-spiral-shaped element for operating said element to withdraw thickened slurry from the vessel.