Abstract: An apparatus for the centrifugal separation of a solid-liquid mixture including an elongate centrifuge drum rotatable about a central axis, a coaxially located conveyor worm within the drum having worm helix flights on a worm drum therein, an opening for the discharge of a light fraction and an opening for the discharge of a heavy fraction, the opening for the discharge of the light fraction located in a radius from the drum axis less than the radius of the worm drum and the opening for the heavy fraction being located at a radius relative to the axis of the drum less than the radius of the worm drum.

Abstract: When a screw-conveyor centrifuge is turned off and its rotation speed diminishes to the point where the centrifugal force is smaller than the force of gravitation, the liquid ring formed inside the centrifuge bowl under the centrifugal force collapses, and a detrimental discharge of liquid takes place at the solids discharge of the centrifuge. In accordance with the method of this invention, the rotation speed of the centrifuge bowl (2) and/or of the screw conveyor (4) is briefly abruptly changed immediately before this critical rotation speed is reached, so that the liquid ring is caused to spiral toward the liquid discharge openings (5) at the other end of the centrifuge (1) by the screw helices (3) of the screw conveyor (4).

Abstract: An apparatus for separating solids and liquid mixtures such as to form concentrated sludge including a solid bowl worm centrifuge which has a slurry admission inlet and outlets for a liquid fraction and for concentrated sludge. A detector for detecting the consistency of the sludge leaving the centrifuge, a conduit for bypassing slurry being supplied from a source to the centrifuge and a control valve for controlling the amount bypassed as a function of the consistency of the sludge fraction and in some instances also a conduit for feeding a dilution liquid to the sludge leaving the centrifuge.

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.

Abstract: A method and apparatus for separating mixtures of different densities into a lighter phase and a heavier phase including a rotary drum providing a cylindrical settling sump at the outer wall, a displacement member rotatably located within the drum forming a settling sump between the displacement member and the drum wall, a discharge element for lighter phase material spaced radially inwardly from the settling sump, a discharge conductor for heavier phase material leading from the settling sump at the deepest location at the outer circumference of the drum, and a compressed air conduit connected to the discharge for heavier phase material aiding in the removal thereof, and vanes on the displacement member aiding in movement of the material through the drum.

Abstract: A first container for receiving fine-grained material to be dewatered with a concentric outer second container for receiving material from the first container and separating liquid, means for driving the containers in unison, circumferentially separated radial first and second plates connected to the first and second containers respectively, rubber blocks between the plates, and means for separately imparting vibration motion to the first and second containers with the vibrations being accommodated by the rubber blocks.

Abstract: An apparatus for partial dehydration of a sludge in the centrifugal field of a centrifuge wherein the residual moisture of the sludge is substantially reduced with a comparatively low compression of the sludge, and the non-effective cone length of the centrifuge is reduced without shortening the sludge dwell time. The invention includes an arrangement of agitator elements within the centrifugal drum, coupled with a following shearing centrifuge and decanter, the shearing centrifuge being connected at the discharge of the centrifugal drum.

Abstract: A device for attaching a filter mesh to the drum of a rotary vacuum drum filter has a number of support elements uniformly disposed about the circumference of the drum and extending along the axial length thereof for carrying the filter mesh and forming individual cells beneath the mesh. At least one filter mesh clamping element is provided between adjacent support elements which includes a spacing body attached to the exterior drum wall and a strip disposed thereabove on the filter mesh and a retainer joining the strip and the spacing body. The spacing body has approximately the same height as the support elements so that the filter mesh is not deformed by the attachment.

Abstract: A jacketed centrifuge for exchanging material between liquids, usually a heavier liquid containing suspended solids and a lighter liquid, including a housing in which there is a drum mounted for rotation, and a conveyor worm mounted for rotation coaxially therewith. Inlet and outlet means are provided for introducing a relatively light liquid into the drum, as well as introducing the heavier liquid containing the solids suspended therein. Many of the elements of novelty are centered around the discharge means which are used for discharging solids from the drum. Basically, the drum is enlarged radially in the vicinity of the discharge means and is provided with various types of devices for discharging the solids into the discharge zone in a controlled manner.

Abstract: A process is disclosed separating solids from phosphoric acid produced by the wet process. This is accomplished by relatively simple means but with a high degree of efficiency with reference to the P.sub.2 O.sub.5 content of the phosphoric acid product.

Abstract: A solid sleeve worm centrifuge having a cylindrical separating portion and a conical discharge portion is provided with a static plate attached to the rotating worm in the area of transition from the cylindrical portion to the conical portion. The static plate prevents the backflow of solids already precipitated from the conical portion to the cylindrical portion of the centrifuge. Intensive dehydration of the separated solids is thus achieved, so that the solids may be stored directly or processed further without additional liquid removal treatment. A liquid withdrawal conduit is provided in the cylindrical portion of the centrifuge to continuously remove liquid separated from a solid-liquid mixture.

Abstract: A rotary separator has a separation vessel comprised of opposed conical sections and has an annular gap between the sections for discharge of solid material. A sleeve surrounds the separation vessel and is attached to the lower conical section thereof by a flexible member allowing axial sleeve movement. The sleeve carries a ring for comovement therewith displaceable to open and close the gap. When the pressure of material in the vessel is sufficient to overcome the flexibility characteristics of the material supporting the sleeve, discharge occurs. The flexible member may be pre-stressed to control the pressure required for discharge to occur, or a chamber communicating with the sleeve and flexible member may be pressurized to selectively displace the sleeve and ring and thereby control discharge.

Abstract: In the dynamic concentration of a suspension, in which the suspension is fed into a filter which has a driven stirring device, and in which the suspension forms a filter cake which is continually remixed by stirring with the suspension being dehydrated and maintained in a liquid state up to a desired degree of concentration, the power consumption of the stirring device is measured, in particular the torque is measured, and the intensity of the stirring motion is controlled in accordance with the measured torque by causing a change in the number of revolutions per minute of the stirring device in response to the torque transgressing an upper limit or a lower limit.

Abstract: A rotary vacuum filter for the separation of solids-liquid mixtures has a rotatably supported filter drum having a stationary hollow conduit extending through the interior of the drum which is attached to a vacuum pump. The drum is rotated in a tank containing a mixture to be separated, so that the vacuum action draws the mixture through a filter disposed on the surface of the drum into the interior thereof, where an interior pump removes the filtered liquid and discharges same through the hollow conduit. At no time during the filtration process is air mixed with the filtered liquid, so that subsequent processing to remove air from the liquid is not required.