Abstract: In order to separate solid-liquid mixtures in a solid bowl centrifuge containing a simply designed, adjustable weir for draining the liquid which makes it possible to control or adjust the level of the liquid in the centrifuge basket (10) during the operation of the centrifuge with the least possible expenditure of energy, the invention proposes to realize the adjustable weir in the form of a stationary, i.e., non-rotating, annular cup (20) that is connected to the centrifuge housing (18) and covers the liquid drain openings (13) of the basket (10) from the outside at a certain distance, wherein the annular cup contains at least one through-opening on its circumference, the size of which can be varied, and where the liquid drains into the liquid collection chamber (15) of the centrifuge housing through the aforementioned through-opening.

Abstract: An apparatus for controlling the level of liquid in a centrifugal separator drum by regulating the flow of liquid out of the drum. The drum includes a plurality of circumferentially spaced openings in a radial end wall of the drum. The openings have movable weir plates in one form controlling the openings with the weir plates movable and positionable in a radial direction by axially movable linkage. In another form, a conduit passage leads from an end opening. By controlling the flow through the openings in the end wall, the liquid level is functionally controlled within the drum. The control mechanisms are situated externally of the drum for ease of repair and to provide control which can be continually monitored.

Abstract: A centrifugal solid bowl worm separator having an outer cylindrical drum and an inner rotatable worm with helical flights on the outer surface with the drum arranged to receive a material to be separated in light and heavy fractions or phases and the mechanism provides for a method of injecting and mixing a fluidizing substance into the heavy fraction material within the drum before it leaves the drum to mix with the heavy fraction within the drum. The fluidizing substance lowers the density of the heavy fraction to enable its discharge by the worm flights. The hydraulic pressure of the liquid helps push the heavy fraction out of the separator which prevents a reverse flow and intermixing of the heavy fraction with the liquid fraction.

Abstract: A rotary centrifuge for the separation of substances at different density having an outer cylindrical housing and a worm within the housing and the worm and housing driven at different rotational speeds, the housing having an opening for the discharge of the heavier fraction with the opening controlled by an external control element preferably stationarily supported and connected by a linkage to a movable valve member for controlling the opening, preferably a ring which moves axially to change the size of an annular discharge gap between the ring and a circular discharge opening in the end wall of the drum, but the opening can also be in the form of axial radial facing openings controlled by a movable valve member.