Abstract: A method and an apparatus for centrifugally separating and classifying a liquid slurry into a solids heavy phase and a light phase fraction with a rotary mounted centrifugal drum having a cylindrical section extending from a first end and completed by a conical section extending toward a second end, a rotary auger within the drum moving slurry from the first to the second end, a slurry inlet at the first end; outlet nozzles extending at an oblique angle opposite the rotational direction of the drum in the cylindrical section for discharge of the heavy phase material, and light phase openings at the second end in the conical section close to the drum axis.

Abstract: Centrifuge for the separation of a suspension into a solids phase and at least one liquid phase, especially decantering centrifuge with separator following in alignment, full-jacket screw centrifuge or the like with screw (2) rotating at differential speed of rotation from its jacket (1), the helices (4) of which fit close against the course of the inner surface of the jacket, which narrows conically over at least some of its axial section looking toward the solids outlet (13) in particular, and between which, the hub (3) of the screw, and the jacket (1) is left the separation section (6), into which the suspension is injected, especially through a cavity (10 & 11 or 10 & 12) in the hub (3) of the screw.

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 decanter centrifuge includes a control system for receiving input AC power and outputting a variable voltage and frequency for controlling the speed of the backdrive and the main drive motor. The control system includes a first controller for converting AC power into DC power and then converting the DC power to AC power at a variable voltage and frequency to the main drive motor. A second controller is connected to the first conversion unit through a common DC bus. The second controller converts DC power to AC power and supplies AC power at a variable frequency to the backdrive motor. The braking force created by the backdrive motor during operation of the decanter centrifuge creates electricity which is passed through the second controller and through the common DC bus to the first controller. Thus, the generated power from the backdrive motor is converted into power for use by the main drive motor.

Abstract: The decanter centrifuge comprises a bowl and conveyor screw rotatably journalled within the bowl and a reduction gear providing a relative rotation of the screw relative to the bowl. The gear is journalled separately relative to the bowl in separate bearings. The housing and the driven shaft of the gear are by means of flexural but torsionally stiff couplings connected with the bowl and conveyor, respectively. The flexural couplings result in that the gear is dynamically insulated from the bowl and does not influence the critical number of revolutions thereof. As a result of this the number of revolutions of the bowl, and thus maximum allowable number of revolutions of the entire centrifuge, may be increased, thereby offering substantially improved separating properties of the centrifuge as a whole.

Abstract: A centrifuge, for example a decanter type centrifuge, comprises a bowl (10) rotatable about a longitudinal rotational axis (Y), an inlet (14) for feeding into the bowl a slurry to be separated, and a helical scroll conveyor (12) rotatably mounted about the rotational axis and adapted to be rotated within the bowl at a different speed from that of the bowl in order to scroll particles adjacent to the bowl wall to a solids discharge end of the bowl. The decanter further comprises a plurality of walls (23) at least partly submerged in the centrate and defining passages therebetween. By providing a plurality of passages, through which the centrate to be clarified can travel, particles (e.g. solids) to be separated from the centrate have a short distance to travel under centrifugal force before entering the boundary layer at the walls of the passages. This enables more of the fine particles in the centrate to be separated out.

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: The present invention is a method for using a horizontal, continuous process auger centrifuge to separate the granulated material of a container from whatever liquid residue remains within the container. Though this technology is suitable for many diverse applications, a primary objective is the continuous separation of the recyclable plastic of a motor oil container from the remaining reusable motor oil within the container after the container has ostensibly been emptied. It is an objective of the method to accomplish this separation in an economically advantageous manner which uses neither a solvent nor a wash process, and which reclaims the oil in a suitable state for reprocessing. In a second method, a rinsing mechanism is employed by which a residual liquid waste, such as soap, may be concentrated and separated in a first rinse stage without introducing the residual liquid waste in dilute form into the waste water treatment process.

Abstract: A three stage centrifuge especially adapted to the separation of oil, water, and solid particles in an emulsion. As an example, the centrifuge may be used to separate sediment and water from a petroleum product such as crude oil. The three stage centrifuge includes a rotatable bowl that spins the emulsion to separate the fluid oil and water into separate pools within the bowl. The solid particles are also moved radially outward within the rotatable bowl by centrifugal force. A conveyor auger contacts the solid particles and discharges the solids from the rotatable bowl through a solids discharge port. Oil discharge tubes contact the oil pool confined between oil baffle plates on the conveyor auger and allow the oil to be discharged from the rotatable bowl. Water weirs contact the water pool and allow the water to be discharged from the rotatable bowl.

Abstract: This invention relates to an improved particulate receiving chamber within a centrifugal separation device and more particularly within a decanter centrifuge. The improved receiving chamber reduces particle disintegration of the particulates which is particularly advantageous if the particulates are subjected to a further centrifugal separation step because particle disintegration compromises the clarification achievable by successive centrifugal separators. The preferred embodiment of the particulate receiving chamber includes a plurality of spray nozzles for spraying fluid in the chamber whereby the fluid absorbs the impact forces of the particulates which impact against surfaces within the chamber.

Abstract: A power-efficient liquid-solid separating centrifuge is disclosed which has power recovery apparatus on the bowl-head of a rotary bowl including a plurality of liquid flow passageways in fluid communication with transfer ports in the bowlhead of the rotary bowl for receiving liquid separated from the slurry introduced into the rotary bowl. These passageways are configured and arranged to direct the flow pattern of the liquid exiting the liquid transfer port to discharge at a radially inward position relative to the liquid transfer port and to flow in a direction with a reduced velocity component in the direction of the rotation of the rotary bowl, thereby recovering power previously expended to accelerate the feed slurry.

Abstract: A decanter for separating a suspension into a solid space and one or more liquid phases, in which a rotatable drum with a screw inside, rests on a machine bed. The screw is rotatable at a speed that is different from the speed of the drum. A transmission is provided between the drum and the screw, and a motor on the bed is connected to the transmission through a torque-transmitter. Intake and outlet lines communicate with the drum to connect the solids and liquid phases. An elastic bearing disengages at least one of the drum, screw, motor, and transmission in at least one direction having a vector component parallel to the axis of rotation of the decanter. The elastic bearing engages the drum, screw and transmission through the attenuator or damper.

Abstract: An axial flow-type pump for separating immiscible fluids having different specific gravities and a discharge manifold fluid connected to the fluid pump for drawing of the fluid having the heavier specific gravity. The fluid pump employs a rotatable impeller mechanism having a hollow core and a decreasing axial pitch in the direction of fluid flow. The fluid interface between the pump and the discharge manifold is adjustable, so that the discharge of the fluid having the heavier specific gravity can be adjusted. The fluids are introduced into the inlet end of the rotatable impeller to produce a high velocity swirling action in the fluids and a low pressure area along the longitudinal axis of the flow line, to generate a high centrifugal force as the fluids move axially and cause the fluid having the heavier specific gravity to migrate to the perimeter. The discharge manifold is then used to draw off the fluid having a heavier specific gravity.

Abstract: A rotating bowl decanter centrifuge including a clarifier section and a beach section for separating a lighter phase from a heavier phase. The beach section includes a conveyor for conveying the heavier phase toward the exterior of the centrifuge. The centrifuge is without a conveyor in the effluent discharge end of the clarifier section. In a preferred embodiment, the clarifier section has an outward incline angle so that the clarifier wall bends away from the bowl's rotational axis. The beach section includes an inwardly inclined outer wall which bends towards the rotational axis of the bowl. It is preferred that the outward incline angle in the clarifier section be on the order of 5.degree. or less.

Abstract: The stator 3 of a low speed, high torque hydraulic motor I is coupled to the drum 2 of a decanting centrifuge, and the rotor 20 of the motor is coupled to a worm 1 within the drum to provide relative or differential rotation between the drum and worm. A light weight, high speed hydraulic motor II is coupled to an end disk extension 14 of the motor I rotor or stator in an overhanging, coaxial position, and its housing 16 is elastically braced against rotation. The speeds of both motors are independently controlled.

Abstract: A decanter centrifuge typically includes a bowl which is rotatable about its longitudinal axis and an independently rotatable screw conveyor mounted coaxially therein. A drive motor is provided to rotate the conveyor at a differential speed from that of the bowl, which has a separate drive motor. An engagement element, in the form of an indexing clutch, an over-running clutch or a selectively controllable clutching element, is provided between the conveyor drive motor and the bowl to simultaneously rotate the bowl and the conveyor during a cleaning in place operation of the centrifuge.

Abstract: Solid-bowl helical centrifuge for separating a suspension, with a stationarily secured intake pipe (31) for supplying the suspension from a stationary infeed point outside the centrifuge to a separation space (3) left between the screw (2) and the bowl (1), whereby, to prevent obstructions due to centrifugal force and malfunctions due to radial displacements and ensure low-maintenance operation, the intake pipe (31) extends into an intake space (32) inside the screw and the end (34) at that location rests against a component (36 and 35, 36 and 38, 36, or 43), which is secured to the screw, by way of a friction bearing (12) with two halves (14 and 15) that are made of a ceramic material where they contact each other.

Abstract: A centrifuge apparatus having an adjustable weir surface for adjusting the depth of an annular pool of a light and heavy phase material mixture therein. A first annular plate is positioned over a discharge outlet and includes a plurality of notches, each defining a generally arcuate opening and in the periphery thereof. A second annular plate is positioned in coaxial parallel juxtaposition with said first annular plate and also includes an identical amount of notches, each defining a generally arcuate opening. The annular plates are angularly positioned with respect to each other such that the generally arcuate openings are placed in overlapping relationship. Therefore, depending upon the relative angular position of the annular plates with respect to each other, the weir length can be increased and decreased.

Abstract: The decanter centrifuge (1) comprises a conveyor screw (5) constructed as a hollow body with a lower average density than the lighter liquid phase of the surrounding slurry. The conveyor (5) thus flows in said liquid phase which is utilized in that the one traditional radial bearing of the conveyor is replaced by a radial support bearing (22) which only during starting and stopping of the centrifuge cooperates with the conveyor (5) in order to prevent it from contacting the bowl (2). In operation, the conveyor is thus only supported in the radial direction at the one end, entailing that the flexural rigidity of the conveyor becomes less important to the maximum allowable number of revolutions of the centrifuge which may then be increased for a given centrifuge, thereby obtaining an improved separating effect.

Abstract: A decanter centrifuge which includes an annular bowl, a hollow tube on the axis of the bowl, and means for discharging from the bowl a first phase of an input sludge, the centrifuge being characterized by a fluid-activated airlift device which includes a discharge line radially supported from the hollow tube, and a fluid supply line for conveying fluid from within the hollow tube to an outer end portion of the discharge line to effect removal from the bowl through said line of another phase of the sludge.

Abstract: Decanter pond level or radius is adjusted incrementally by means of an annular retainer plate having an eccentric recess formed in the surface thereof which faces hub openings. The recess receives a plate dam slidably therewithin. Each retainer plate or retainer, typically 6 in number, is mounted over a hub opening. The dam is mounted over the hub opening such that its weir surface substantially coincides with the rotating pond level. By rotating the retainer around the prepositioned dam in increments preset in the retainer, the dam moves radially inwardly or outwardly depending upon the position of the recess eccentricity with respect to the hub opening. The dam is provided with two different weir surfaces, each usable with a different side of the dam, thus permitting the number of adjustments to the pond level to be doubled. A modification discloses infinite or stepless pond level adjustments.

Abstract: A high capacity continuous solid bowl centrifuge is disclosed having longitudinal vanes which cooperate with helical flights to form longitudinal channels. The longitudinal vanes may be curved vanes or they may be planar vanes disposed either radially or at an acute angle relative to a radius from the longitudinal axis of the centrifuge. In operation, the solids/liquid mixture fed into the centrifuge is separated, and the liquids move in a "plug-flow" manner in the longitudinal channels parallel to the axis of rotation, toward effluent discharge ports disposed at one end of the centrifuge. The separated heavier solids are moved by the flights toward the opposite end of the centrifuge where they exit through a solids discharge port.

Abstract: A solid-and-liquid separation device revolving at high speed, comprising a bowl having a screw therein, said bowl being formed with cylindrical and canted sections, thereby permitting separation of a fluid containing solids into light and heavy liquids and solids.

Abstract: The solid bowl screw centrifuge consists of a housing (1) in which a drum (2) is rotatable. A rotatably mounted conveyor screw (3) is situated inside the drum (2). The drum (2) and screw (3) rotate at slightly differing speeds of rotation when in operation. The housing (1) is cylindrical in the region of the clarifying part (I) and conical in the region of the demoisturizing part (II). The suspension inflow (5,6) opens into the hollow screw core (12) at a location between the clarifying part (I) and the demoisturizing part (II). The liquid discharge consists of an overflow weir (16) or stripping pipe (9) on the clarifying part (I). The solids discharge (4) is situated at the end of the demoisturizing part (II). The screw (3) is arranged within the clarifying part (I) on the cylindrical hollow screw core (12) whose peripheral surface is partly or completely equipped with an after-clarifying device through which fluid flows in a radial direction.

Abstract: Separating elements (14) arranged about a central shaft (1a) rotate in common about the main axis (A) and individually about their longitudinal axes (B). A centrifugal distributor (6) distributes fine-grain mineral mixture mixed with fluid uniformly to the separating elements (14). In each separating element (14) the partial material flow (2a) is set in rotation about the longitudinal axis (B) by entrainment vanes (18) arranged in a first separating element section (15a) and the heavy fraction is centrifuged on to the separator wall (16a). In the second section (15b), formed as conical tubular worm conveyor, which contains no entrainment vanes, the heavy fraction is transported to the collecting chamber (21) and discharged through first discharge openings (22), the fine-grain mineral mixture being fluidized in pulsation on the separating wall (16b) by the combined rotating movements and the heavy fraction being concentrated.

Abstract: A method and apparatus for controlling a worm centrifuge wherein the centrifuge drum is driven by a first hydraulic motor and the screw conveyor is driven by a second hydraulic motor and first and second valves are connected to control the flow of hydraulic fluid to the motors and the valves receive the full output of a constant delivery pump. Control of the valves is obtained by a torque measuring device measuring the torque input to the screw conveyor and the torque measuring device has a control which opens the valve to a motor for the screw conveyor with increase in torque and simultaneously closes the valve to the motor to the centrifuged drum proportionately so that the total flow of the pump is utilized by the motors.

Abstract: A mechanism and method for treating sludge material for separating the material into solid and liquid phases in a centrifugal separator having a rotating drum and an advancing screw driven at a speed differential relative to the drum, conveying a solid phase of the sludge to a digester tower for generating a biogas, delivering the biogas to a collection chamber and feeding the biogas to a gas powered prime mover connected to drive the centrifugal separator through a hydraulic pump and motor drive with the biogas generated and supplied to the motor commensurate with the speed of operation of the separator.

Abstract: Dam members are provided with an upper discharge weir surface permitting flow of separated liquid thereover during normal or stable centrifuge operations, and a notch or the like interrupting said weir surface or disposed immediately therebelow to provide a lower discharge weir surface permitting flow of separated liquid therethrough to insure an absence of liquid being discharged at solid discharge ports during start-up.

Abstract: An improved screw decanter type centrifugal concentrating machine for the type including a bowl and a screw conveyor rotatably supported within the bowl in the coaxial relation is disclosed. The screw conveyor is rotated at a different rotational speed from that of the bowl and an arrangement is made such that liquid initially supplied prior to separating, concentrated liquid and residual liquid after completion of separation are continuously supplied and discharged through the hollow space in the hollow shafts of the bowl and the screw conveyor. To properly adjust discharge rate of concentrated liquid and residual liquid from the machine or concentration of solid material in both liquids, throttle valves are disposed at the position located midway of discharge passages extending from the hollow shafts. The throttle valves are preferably designed in the form of an automatically controlled valve. Suspension to be treated is introduced into the bowl by way of guide vanes on the side wall of the bowl.

Abstract: Decanter-type separating apparatus comprising within a rotatably mounted tapered and cylindrical barrel a solids-transporting screw rotating at a speed different from the barrel speed, the aforesaid apparatus being characterized by the screw having in an intensive clarification region a pitch substantially greater than used in the past, to stabilize the flow as far as possible and to obtain particularly effective and efficient clarification. In the intensive clarification region, the pitch is much greater than ten degrees and preferrably is within a range of forty to fifty degrees, in certain cases on the order of up to sixty degrees.

Abstract: A fully jacketed centrifuge with a helical conveyor for separating mixtures of solids and liquid has apertures below the surface of the liquid in the jacket of the drum. Some of the centrifuges solids are let off through the apertures. Inside the helical conveyor is, in addition to one inlet space for the mixture of solids and liquids, another inlet space that has an access and that communicates with channels that extend in the vicinity of the apertures into the vicinity of the jacket. The apertures are positioned in interchangeable mouthpieces. The concentration of solids flowing off out of the apertures is controlled by constantly returning part of the solids that emerge from the flowoff through the access, the second inlet space, and the channels into the vicinity of the apertures.

Abstract: At each end the bowl of the centrifuge is journalled for rotation in a bearing housing from which the prevailing bearing loads are transmitted to a support means through a system of springs, the spring rate of which is so low that the natural frequency of the centrifuge is substantially below its normal rpm, preferably lower than 15 percent thereof. The bowl can then rotate at a high rate of rotation without concomitant vibration problems.In order to avoid undesirable transverse forces acting on the bowl a pulley mounted on its protruding shaft end may be pre-loaded in diametrically opposed directions by means of two pretensioned belt drives each of which is trained over a stationarily mounted pulley. At least one of the last mentioned pulleys is driven by a motor.

Abstract: The screw centrifuge has a cylindrical clarifying part and a conical desiccating part which is provided with axial supply pipes for a washing liquid and with openings for the passage of the washing liquid into the chamber between the drum and the screw core. A substantial improvement in the washing effect is achieved in that the openings are connected to a liquid distributor which is positioned along a cylindrical helix and which charges the washing liquid regularly along the screw flank over at least one turn in the vicinity of the screw core. The liquid distributor either comprises an overflow channel which is positioned in or directly upstream of the screw flank, or it is formed from a compact series of nozzles which are directed at the screw flank. It is an essential feature of this arrangement that the solids which are pushed up by the screw flanks are covered and saturated regularly with the washing liquid.

Abstract: A centrifugal separator having a rotary bowl for receiving feed which forms a pool within the bowl a skimmer movably mounted to fixed structure within the bowl for removing liquid from the pool to a discharge system with an outlet external to the bowl, and adjustment means operable from outside the bowl for adjustably moving the skimmer oppositely toward and away from the bowl axis to vary the pool depth. However, in accordance with the invention, the skimmer adjustment means includes skimmer mounting means movably connecting the skimmer to the fixed structure within the bowl so as to enable adjustment movements thereof by the adjustment means and so that the hydraulic thrust of the pool liquid against the skimmer is applied by the mounting means substantially entirely to the fixed structure. Preferably, the adjustment movement of the skimmer enabled by the mounting means are essentially radial only to the axis of the bowl, thus greatly reducing the amount of adjustment movement required.

Abstract: A decanting type centrifuge having a main bowl which is adapted to be rotated about its longitudinal axis and which contains a helical scroll conveyor which is arranged to rotate about the main bowl axis at a slightly different speed to the main bowl for scrolling separated solids to a solids discharge end of the bowl. The centrifuge includes a means which acts to isolate a gas volume radially inwardly of the inner liquid surface within the bowl and also a passage arrangement which enables gas to be extracted continuously from the isolated gas volume to a location external to the main bowl.

Abstract: A method and mechanism for controlling the operation of a centrifugal separator having a relatively rotating drum and screw conveyor whereby the speed of each is measured and the torque for driving the screw is measured and the speed differential control is in a predetermined functional relationship to the torque and at a particular maximum and minimum value of torque, the speed differential being changed independently of torque and when a predetermined change in torque is obtained, the predetermined functional relationship between the torque and speed differential being changed to a different characteristic step-wise with the characteristic or relationship being shifted step-wise.

Abstract: A worm centrifuge with a rotatable drum and a rotatable screw therein and separate drives with a speed governable clutch between the drives to provide for a start-up by one of the drives, preferably a speed governable drive, and arranged so that the clutch can be released for independent driving of the drum and screw during normal operation.

Abstract: The apparatus for separating a solid-liquid mixture has a housing with a metal screw conveyor adapted to rotate relative to the housing on a common longitudinal axis. The conveyor has helically-formed flights about its axis. Replaceable inserts are mounted on the entire circumference of the flanks of the flights with each insert having metal secured to the flights and integral wear-resistant material adapted to function as the working surface.The inserts are formed by first making a metal annular member of the same material as the conveyor flight. The wear-resistant, hard-facing material is then deposited on one radial surface of the metal annular member in a manner to simultaneously form and fuse the wear-resistant, hard-facing material to the annular member. The metal part of the annular member is then machined to proper dimensions and the annular member cut into segmental inserts. The segmental inserts are then mounted on the conveyor flights.

Abstract: A centrifuge conveyor is provided with improved hard surfacing wherein assemblies of backing members and wear-resistant members are welded by the backing member to the conveyor. An assembly may be made unitary by providing a hole in either or both of the wear-resistant member and the backing member and securing them with means extending through the hole or holes. In the event that repair is necessary, an individual assembly may be replaced by welding technique, or the backing tile may be left in place and only the wear-resistant member replaced by removing and replacing the securing means. Each fragile wear-resistant member is braced against deflection at its outer portion through its backing member to the conveyor. The embodiments employ a plurality of wear-resistant members, each such member being accurately pressed from sintered tungsten carbide.

Abstract: A decanter centrifuge has a drum driven by a main driving motor via belts and a worm gear located in the drum so that it can rotate. The worm gear is driven by a hydraulic motor with a differential rate of rotation which rotates with the drum, thus providing a slip drive unit. A hydrostatic coupling is connected between the main drive motor and the belt drive of the drum. A pressure line of the pump of the hydrostatic coupling is connected hydraulically with the feed line of the hydraulic motor of the worm gear through a flow-control valve. With this arrangement, only a single pump, that is, the pump of the hydrostatic coupling is required to accelerate the drum and regulate the rate of rotation of the drum on the one hand, and simultaneously to feed the slip drive unit, on the other.

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 method and apparatus for regulating the differential rpm of two rotating parts, such as the external drum and internal worm conveyor of a worm centrifuge, undertakes an electronic measurement and sampling of the rotational during the course of operation of a particular device under speeds of each part and supplies this information to a microprocessor which calculates the respective rotational speeds of the parts and relays a signal to the drive device for one of the parts in order to maintain a preselected rpm differential between the rotational speeds of the two parts. Different characteristic curves are stored in the microprocessor for optimum rpm differential during the course of operation of a particular device under different conditions, such as for different sludge consistencies in the case of use with a centrifuge. If deviation of the actual rotational speed of one of the parts from the optimum value is detected, the microprocessor operates to return operation to the optimum values.