Centrifuge employing variable height discharge weir

Claim 2

Centrifuge apparatus for separating solids from liquids from feed comprising a solids-liquids mixture fed into a bowl of said centrifuge mounted for rotation about an axis of rotation and including screw means cooperating with means for rotating said bowl for conveying said solids from said mixture for discharge out a rear portion of said bowl and liquid for discharge out a front portion of said bowl, said centrifuge having a hub at a front portion thereof mounted for rotation with said bowl, said hub having a plurality of spaced openings therethrough communicating with said fed solids-liquids mixture, the improvement to said centrifuge apparatus comprising, a dam plate secured to each of said hub openings, each of said dam plates having variable height discharge weirs provided therein, one of said weirs having a curved upper weir surface for controlling level of separated liquid within said bowl during normal or stable centrifuge operation, and other of said weirs comprising a lower cut-out portion disposed along said upper weir surface and substantially immediately therebelow for permitting separated liquid to be discharged therethrough during centrifuge start-up operations wherein said separated liquid is discharged at a lower rate than during said stable centrifuge operation.

Claim 3

Centrifuge apparatus of claim 1 wherein said discharge weir surfaces are integral with said hub.

Claim 4

Centrifuge apparatus of claim 1 wherein said upper weir surfaces form a substantially straight line approximating surface shape of said separated liquid.

Claim 5

Centrifuge apparatus of claim 1 wherein said cut-out poriton is a notch interrupting said curved weir surface.

Claim 6

Centrifuge apparatus of claim 4 wherein said notch is rectangularly configured.

Claim 7

Centrifuge apparatus of claim 4 wherein said notch is V-shaped.

Claim 8

Centrifuge apparatus of claim 1 wherein said cut-out portion is circular or elliptical.

Claim 9

Centrifuge apparatus of claim 7 wherein said circular or elliptical cut-out portion interrupts said curved weir surface.

Claim 10

Centrifuge apparatus of claim 1 wherein distance between said axis of rotation and said cut-out portion is greater than distance between said axis of rotation and said rear portion of said bowl where said solids are discharged.

Claim 11

Centrifuge apparatus of claim 1 wherein said curved upper weir surface substantially coincides with level of liquid in said rotating bowl.

Claim 12

Centrifuge apparatus for separating solids from liquids from feed comprising a solids-liquids mixture fed into a bowl of said centrifuge mounted for rotation about an axis of rotation and including screw means cooperating with means for rotating said bowl for conveying said solids from said mixture for discharge out a rear portion of said bowl and liquid for discharge out a front portion of said bowl, said centrifuge having a hub at a front portion thereof mounted for rotation with said bowl, said hub having a plurality of spaced openings therethrough communicating with said fed solids-liquids mixture, the improvement to said centrifuge apparatus comprising, a dam plate secured to each of said hub openings, each of said dam plates having discharge weir surface for controlling level of separated liquid within said bowl during normal or stable centrifuge operation, a plurality of spaced liquid discharge holes provided in said hub wherein distance between said axis of rotation and said holes is greater than distance between said axis of rotation and said rear portion of said bowl where said solids are discharged, said holes permitting said separated liquid to be discharged therethrough during centrifuge start-up operations wherein said separated liquid is discharged at a lower rate than during said stable centrifuge operation.

Claim 13

Centrifuge apparatus for separating solids from liquids from feed comprising a solids-liquids mixture fed into a bowl of said centrifuge mounted for rotation about an axis of rotation and including screw means cooperating with means for rotating said bowl for conveying said solids from said mixture for discharge out a rear portion of said bowl and liquid for discharge out a front portion of said bowl, said centrifuge having a hub at a front portion thereof mounted for rotation with said bowl, said hub having a plurality of spaced openings therethrough communicating with said fed solids-liquids mixture, the improvement to said centrifuge apparatus comprising, a dam plate secured to each of said hub openings, each of said dam plates having discharge weir surface for controlling level of separated liquid within said bowl during normal or stable centrifuge operation, a plurality of spaced liquid discharge holes provided in said hub wherein distance between said axis of rotation and said holes is greater than distance between said axis of rotation and said rear portion of said bowl where said solids are discharged, said holes permitting said separated liquid to be discharged therethrough during centrifuge start-up operations wherein said separated liquid is discharged at a lower rate than during said stable centrifuge operation.

Claim 14

Centrifuge apparatus of claim 11 wherein said discharge weir surfaces for controlling level of separated liquid within said bowl during normal or stable centrifuge conditions are integral with said hub.