Abstract: A solid-bowl centrifuge has a rotatable drum having an interior and a space adjacent to the interior of the drum for receiving separated off liquid conveyed from the drum. A weir disk is disposed between the interior of the drum and the chamber and is rotatable with the drum. Liquid is conveyed past an inner diameter of the weir disk to the space and that determines a level of the liquid in the interior of the drum. Two barrier disks on opposite sides of flat surfaces of the weir disk are gas-tightly joined together by a cylinder extending through the inner diameter of the weir disk. One barrier disk is immersible in the liquid in the interior of the drum and the other barrier disk is immersible in the liquid in the space. The barrier disks and cylinder define a chamber and a gas-supply channel supplies gas to the chamber to vary the pressure therein and thereby vary the level of the liquid in the interior of the drum.

Abstract: A continuous, completely jacketed countercurrent centrifugal extractor of the type utilized to mix and separate two liquids that have different specific gravities and enter through separate inlets. The extractor has at least one overflow weir in a mixing zone between the inlet for the specifically lighter and the inlet for the specifically heavier liquid phase and a division of the mixing zone into mixing-and-separation compartments. Access channels empty into the vicinity of the inner surface of a drum jacket and into that of the heavier phase, to conduct the lighter phase out of the compartment inside the hub of a conveyor worm into the initial mixing-and-separation compartment. One or more overflow channels also empty into the vicinity of the heavier phase, in the overflow weir to divert the lighter phase separated in the initial mixing-and-separation compartment into another and subsequent mixing-and-separation compartment.

Abstract: Centrifuge for separation of a mixture of solid particles, a specifically heavier liquid, and a specifically lighter liquid into the three component parts, having a conveyor helix 3 for moving the solid particles to one end of the drum 1, and, at the other end of the drum, a paring system, i.e. a centripetal pump 18, for removing one of the liquids under pressure and a catchment 24 for the removal of the other liquid without pressure. In order to permit removal of either the heavier phase (FIG. 1) or the lighter phase (FIG. 2) by the paring system a separating disk 6, 7 is disposed adjacent each end of the drum. The separator disks project radially outwardly from the helix and extend through the lighter liquid and partially through the heavier liquid. Each disk is provided with a closable opening at the level of the zone of separation. A weir for the overflow of liquid to go to the catchment 24 is provided by a conduit 21 having an open end disposed adjacent the solids discharge end of the drum.