Apparatus for production, withdrawal and transfer of highly viscous slurry

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 liguid near the top of the vessel, and a slurry withdrawal apparatus 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 throuah 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 part of said distance when said element is fully extending into said vessel, and a drive mechanism for said open-spiral-shaped element for operating said element to withdraw thickened slurry from the vessel, and wherein said open-spiral-shaped element is insertable into and removable from said vessel through said opening, and wherein said drive mechanism intermittently rotates said element about a longitudinal axis, and also reciprocates said element back and forth along said axis into and out of said vessel.

Apparatus for separating components of slurries by gravity settling thereby forming a thickened slurry in the form of a paste slurry or a solid paste 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 means, an outlet for the clarified liquid near the top of the vessel, a ranking 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 for a distance directly into said interior of the vessel through an opening near said bottom wall, said open spiral-shaped element being in direct and unconfined communication with said interior of the vessel over a majority of said distance, and drive means for rotating the element about a longitudinal axis thereof in a direction to remove thickened slurry from said vessel through said opening.

Apparatus for separating components of slurries by gravity settling thereby forming a thickened slurry in the form of a paste slurry or solid paste and a clarified liquid, said apparatus 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 means, an outlet for the clarified liquid near the top of the vessel, and a slurry withdrawal apparatus 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 slidably mounted for selective insertion into and withdrawal from the interior of the vessel at or near the bottom wall, means for slidably moving said element into and out of the interior of the vessel, and means for rotating said element at least when said means for slidably moving the element moves said element into said interior of the vessel.

A method of withdrawing a slurry of high solids content from a vessel, which comprises introducing into a vessel containing a slurry of high solids content an elongated open-spiral-shaped element in open and unconfined exposure to said slurry over at least a part of the length of the element, said spiral-shaped element being introduced through an outlet in a wall of the vessel, and operating said spiral-shaped element to withdraw said slurry from said vessel through said outlet, wherein said open-spiral-shaped element is reciprocated longitudinally into and out of said vessel to remove said slurry, and wherein movement of said spiral-shaped element into said vessel is accompanied by rotation of said element to cause said element to drill into said slurry, and wherein said spiral-shaped element is fixed against rotation when said element is moved out of said vessel.

Apparatus for separating components of a slurry by gravity settling, comprising:

• a vessel having an interior in which separation of said slurry takes place to form a thickened slurry at a bottom of said vessel and a clarified liquid at a top of said vessel, said vessel having an outlet for said clarified liquid near said top of said vessel and an outlet for said thickened slurry at or near said bottom of said vessel;
• a raking device extending into said interior of said vessel and operable to form a raked region within said vessel above said outlet for thickened slurry where said thickened slurry is formed:
• an elongated, rotatable, open-spiral-shaped element extending permanently or intermittently for a distance in said interior of said vessel, said element being in direct and unconfined communication with said interior of the vessel over a majority of said distance when said element extends fully into said interior of said vessel, and said element being operable to engage physically with a portion of said thickened slurry in said interior of said vessel and to transport said portion of said thickened slurry through said outlet of said vessel.