Abstract: A disc stack separator and an accelerator disc for a disc stack separator, especially a centrifugal nozzle separator, has curved blades mounted on a cone-shaped shell. The blade configuration assists in directing flow to space for the nozzles in the centrifugal separator bowl in an optimal manner, thus reducing the power consumption of the separator.

Abstract: This invention is for a centrifugal separator comprised of a group formed by: a central feed chamber (10) fed by a feed pipe (20); a separation chamber (30) including a number of frustoconical disks (3); a first recovery chamber (11) in communication with a first liquid phase recovery pipe (21) and a gaseous phase recovery pipe (23); and a second recovery chamber (12) communicating with a second liquid phase recovery pipe (22), where the group is encompassed by a rotating envelope (1), where the central feed chamber (10) is in liquid fluid communication with the separation chamber (30), and in gaseous fluid communication with the first recovery chamber (11), where the separation chamber (30) is in fluid communication with the first and second recovery chambers where the centrifugal separator is encompassed by pressurizable stationary casing (4a, 4b).

Abstract: A blood washing system including a rotor defining an internal chamber and a skimmer assembly configured to move a withdrawal needle within the internal chamber. A multi-component fluid, such as a whole blood sample, can be fed into the internal chamber via a feed tube, where the rotor can be rotated to fractionate the multi-component fluid. A brake can be applied to the rotor to cease rotation or rotated at a slower speed to allow the fractions of the multi-component to settle on a bottom wall of the rotor. The withdrawal needle is moveable within the internal chamber to align an orifice of the withdrawal needle for withdrawing the liquid fractions and isolate the solid fractions. Wash fluids can be added to the internal chamber to repeat the wash cycle without removing the solid fractions. The washed solid fractions can be withdrawn via the feed tube and collected.

Abstract: The invention relates to a device for separating blood into its components and a method for the same and use of such a device. The device comprises a magnetic drive device, which causes a container to rotate about its own axis, wherein the container has at least one open end and at least one inlet therein and is suspended in a magnetically floating manner.

Abstract: The invention refers to a centrifuge for separating whole blood into its blood components and a method for extracting a highly enriched thrombocyte concentrate out of whole blood. For this purpose, the centrifuge comprises a closed loop and/or open-loop control unit as well as a drive unit coupled to the closed loop and/or open-loop control unit, a rotor (12) having at least two container receptacles (14a, 14b; 16a, 16) for removably holding containers (18, 20, 22, 24) being in fluid communication with each other, at least one sensor arranged between the container receptacles (14a, 14b; 16a, 16b) and coupled with the closed loop and/or open-loop control unit for detecting a separation layer. Herein, a motor/gear unit (30a, 30b, 32a, 32b) coupled to the closed loop and/or open-loop control unit is associated with each of the container receptacles (14a, 14b; 16a, 16b).

Abstract: A blood component separation device includes a centrifuge bowl for separating a blood component from blood, a plasma bag for storing a plasma component, a platelet intermediate bag for storing high-concentration platelet liquid having high-concentration of platelets, and a temporary storage bag (also used as a buffy coat bag) for storing low-concentration platelet liquid having low-concentration of platelets. The blood component separation device performs control, from the second cycle onward, to mix the low-concentration platelet liquid stored in the temporary storage bag in the immediately preceding cycle with whole blood to supply the mixed liquid to the centrifuge bowl. An amount of high-concentration platelet liquid to be collected in the platelet intermediate bag in the first cycle is set to be smallest among all cycles, and an amount of high-concentration platelet liquid to be collected in a last cycle is set to be greatest among all the cycles.

Abstract: A centrifugal separator includes a separation barrel with an upper end, a lower end, a central axis, and a cylindrical wall defining a separation chamber. A spin plate extends substantially across the separation chamber adjacent to the lower end thereof. A post including a central passage extends from the spin plate along the central axis of the separation barrel. The post includes at least one opening for fluid to flow from the central passage of the post to the separation chamber. An inlet in fluid communication with the separation chamber allows solids-laden fluid to flow into the separation chamber. An outlet in fluid communication with the separation chamber allows substantially-clean fluid to flow out of the separation chamber and out of the device.

Abstract: A continuous centrifuge including: a rotor configured to separate a sample; a centrifuge chamber configured to accommodate the rotor; a driving part configured to rotate the rotor; a sample line configured to continuously supply and discharge the sample to and from the rotor during rotation of the rotor; and an air detecting sensor provided to a supply side and a discharge side of the sample line.

Abstract: A continuous self-cleaning centrifuge assembly having a feed inlet for unclarified liquid and first and second outlets for clarified liquid. Solids are discharged out of a solids holding space in the centrifuge in response to comparison of a measured turbidity to a predetermined turbidity parameter of clarified liquid bled in a detection line in communication with the centrifuge at the second outlet. The turbidity is affected by the degree of build up of solids in the centrifuge. A method of optimizing the clarified liquid outflowing from the centrifuge includes the steps of controlling the flow rate of unclarified liquid into the centrifuge in response to the turbidity of the clarified liquid flowing out of the centrifuge and discharging solids out of a solids holding space in the centrifuge in response to the turbidity measurement.

Abstract: Blood separation methods are provided for mid-processing calculation of blood composition. Blood is conveyed into a device having an outlet line and the device is spun to separate platelets from the blood. A flow of platelets is conveyed from the device by the outlet line and the platelets in the outlet line are optically measured. With said optical measurement, a current platelet yield, a platelet pre-count, the volume of blood to process to collect a target amount of platelets, and/or the processing time required to collect a target amount of platelets is calculated. The optical measurement can also be used to calculate an amount of storage fluid to convey into a collection container with the platelets.

Abstract: A system and method for supplying clean dry gas to gas seals of a compressor. The system uses a rotary separator magnetically coupled to a source of rotational power, along with a gas stream cooling unit configured to condensate liquids out of a wet gas stream before the wet gas stream is supplied to the rotating separator. The system may further include a gas stream pressure booster, a heating unit to heat a dry gas stream generated by the rotary separator, and a controlled recirculation loop configured to continually recirculate the wet gas through the driven rotary separator until a desired amount of condensates are removed from the wet gas stream.

Abstract: The PRP separator-concentrator of this invention is suitable for office use or emergency use for trauma victims. The PRP separator comprises a motorized centrifugal separation assembly, and a concentrator assembly. The centrifugal separator assembly comprises a centrifugal drum separator that includes an erythrocyte capture module and a motor having a drive axis connected to the centrifugal drum separator. The concentrator assembly comprises a water-removal module for preparing PRP concentrate. The centrifugal drum separator has an erythrocyte trap. The water removal module can be a syringe device with water absorbing beads or it can be a pump-hollow fiber cartridge assembly. The hollow fibers are membranes with pores that allow the flow of water through the fiber membrane while excluding flow of clotting factors useful for sealing and adhering tissue and growth factors helpful for healing while avoiding activation of platelets and disruption of any trace erythrocytes present in the PRP.

Abstract: A centrifugal separator includes devices for light matter extraction and for heavy matter extraction. Each embodiment provides for a plurality, e.g., two or more stacked or layered chambers, and connected to a central compartment of the chambers is a rotating drive shaft. In the light matter extraction, a central conduit feeds fluid input into the lower chamber. An upper portion of the lower chamber communicates with the lower portion of a mid chamber via a port formed in a plate dividing the chambers. The upper portion of the mid chamber communicates with the lower portion of an upper chamber via a port formed in a plate dividing the chambers. The chambers can be fixably connected to one another. In the heavy matter extraction an initial feed conduit feeds fluid into the upper chamber.

Abstract: A separator and method according to which substances having relatively high densities are separated from a pressurized flow stream.

Abstract: A method and an apparatus for continuous processing of intra- or postoperative blood loss for autotransfusion. According to the present invention, certain cells of the cell suspension to be processed, mainly the red blood cells, are concentrated by centrifuging in a separation unit and removed from the separation unit without being rinsed or washed in the separation unit. The concentrated cell fraction is diluted with a physiological solution, preferably a Ringer's solution, after being removed from the separation unit.

Abstract: A centrifugal method, and corresponding system, for processing blood to collect platelet rich plasma. A separation chamber is filled with blood from a fill syringe by rotating the separation chamber at a fill rotation rate and pumping the blood from the fill syringe. A soft spin is used to initially separate red blood cells from platelets by spinning the separation chamber at a soft spin rate. A percentage of the blood is drawn from the separation chamber back into the fill syringe to remove separated red blood cells. A second portion of the separated blood is drawn from the separation chamber until a red blood cell/platelet interface is detected. A hard spin is performed by spinning the separation chamber at a higher rate and connecting tubing is cleared of red blood cells by drawing a predetermined clearing volume. The platelet rich plasma is then collected in the collection syringe.

Abstract: An extracorporeal blood processing system is disclosed which includes a variety of novel components and which may be operated in accordance with a variety of novel methodologies. For instance, the system includes a graphical operator interface which directs the operator through various aspects of the apheresis procedure. Moreover, the system also includes a variety of features relating to loading a blood processing vessel into a blood processing channel and removing the same after completion of the procedure. Furthermore, the system also includes a variety of features relating to utilizing a blood priming of at least portions of the apheresis system in preparation for the procedure. In addition, the system includes a variety of features enhancing the performance of the apheresis system, including the interrelationship between the blood processing vessel and the blood processing vessel and the utilization of high packing factors for the procedure.

Abstract: A centrifugal blood separator for separating whole blood into at least two blood fractions such as a plasma fraction and a blood cell fraction is disclosed. The blood separator has a centrifuge vessel with a separation chamber having at least two sections with different diametric sizes. The large diameter section collects the heavier blood cell fraction during centrifugation. The smaller diameter section collects the lighter plasma fraction. Fluid communication subassemblies preferably have a feed conduit, a product or an outflow conduit and a vent which are mounted in a non-rotatable part and positioned in an extending or extendible manner into the separation chamber to allow blood fractions to be removed while the centrifuge vessel is rotating or after rotation has stopped depending upon specifics of the particular embodiment.

Abstract: An extracorporeal blood processing system is disclosed which includes a variety of novel components and which may be operated in accordance with a variety of novel methodologies. For instance, the system includes a graphical operator interface which directs the operator through various aspects of the apheresis procedure. Moreover, the system also includes a variety of features relating to loading a blood processing vessel into a blood processing channel and removing the same after completion of the procedure. Furthermore, the system also includes a variety of features relating to utilizing a blood priming of at least portions of the apheresis system in preparation for the procedure. In addition, the system includes a variety of features enhancing the performance of the apheresis system, including the interrelationship between the blood processing vessel and the blood processing vessel and the utilization of high packing factors for the procedure.

Abstract: A method and apparatus for controlling the density of the solids separated from a feed slurry by selectively recirculating the separated liquid component of the feed slurry to change the feed slurry's density when an unwanted density of the separated solids is detected. Further, the efficiency of the separation is increased by recirculating and recharging unused catalyst into the feed slurry where it is used to assist in the separation of the solids.

Abstract: Blood processing systems and methods establish on line communication between a container and a source of blood containing leukocytes and platelets, such as a human donor. The systems and methods create a centrifugal field between the source of blood and the container that separates from the blood an unfinished suspension of platelets having a first physiologic characteristic different than the desired physiologic characteristic. The systems and methods pump the unfinished platelet suspension outside the centrifugal field through a finishing device. The finishing device changes the first physiologic characteristic to the desired physiological characteristic, thereby creating the finished platelet suspension. The systems and methods convey the finished platelet suspension from the finishing device directly into the container. The systems and methods function without interrupting the on line communication between the container and the source of blood.

Abstract: An extracorporeal blood processing system is disclosed which includes a variety of novel components and which may be operated in accordance with a variety of novel methodologies. For instance, the system includes a graphical operator interface which directs the operator through various aspects of the apheresis procedure. Moreover, the system also includes a variety of features relating to loading a blood processing vessel into a blood processing channel and removing the same after completion of the procedure. Furthermore, the system also includes a variety of features relating to utilizing a blood priming of at least portions of the apheresis system in preparation for the procedure. In addition, the system includes a variety of features enhancing the performance of the apheresis system, including the interrelationship between the blood processing vessel and the blood processing vessel and the utilization of high packing factors for the procedure.

Abstract: A method and a device for separating a component, such as fibrin monomer from blood, by centrifugation, involve feeding of blood admixed an anticoagulant to a first annular chamber in a device, where the annular chamber is defined by a cylindrical outer wall and a cylindrical inner wall, both walls extending coaxially about a common axis, as well as by a top wall and a bottom wall. The top wall or the bottom wall is formed by a piston body displaceable within the first chamber. This method involves furthermore a centrifugation of the device about the said common axis to substantially separate blood into a cell fraction and a plasma fraction followed by the resulting plasma fraction being transferred while influenced by the piston body to a second chamber defined by an outer cylindrical wall. The outer cylindrical wall extends coaxially with the said common axis, whereby a fraction with fibrin I is caused to be separated in the second chamber while a suitable enzyme is being added.

Abstract: An apheresis apparatus for increasing the purity and yield of platelets separated from donated whole blood by centrifugation incorporates a centrifuge for separating whole blood into lower, intermediate, and higher density components. The centrifuge has inlet and outlet ports in selective fluid communication with a container for receiving lower density blood component from the outlet port. A pump is coupled to the container and the inlet port for recirculating lower density blood component from the first container through the inlet port into the centrifuge at a first, substantially constant, rate so as to widen the region of the centrifuge occupied by the intermediate density component without causing the intermediate density component to exit the centrifuge, and subsequently at a second rate, so as to displace intermediate density component from the centrifuge.

Abstract: A centrifuge bowl is used for separating particulate materials of different specific gravity and has a first generally frusto-conical portion of the peripheral wall of the bowl over which the materials are caused to flow, and two axially spaced annular recesses downstream of the first portion and prior to an open mouth of the bowl. The feed materials pass over the peripheral wall causing heavier material to collect within the recesses and the lighter material to discharge through the open mouth. Each recess has a series of angularly spaced discharge ports controlled by pulsed valves. In front of each discharge port is provided a spherical body which directs the material to all sides around the body as it moves towards the discharge port in a generally conical shape. The conical shapes of adjacent discharge ports overlap to provide full discharge of all the material. The first recess acts as a main concentrate collector.

Abstract: Upper and lower bowl members are mounted on a common linear cylindrical member and a relief valve provides controlled gas pressure within a centrifuge housing in a low speed decanting centrifuge for separating relatively large particulate material (e.g. yeast) from a feedstock. The centrifuge may be clamped to a container and a pressure differential is created between the centrifuge housing and the container to, in turn, force feedstock upwardly into the lower bowl of the centrifuge. A stack of frustonconical discs carry supernatant downwardly and inwardly for vertical transfer to a discharge chamber, Particulate matter is centrifugally discharged continuously between engageable surfaces of the lower bowl member and the upper bowl member. Hydraulic forces generated within the bowl are isolated from a thrust bearing supporting the bowl and transferring drive forces to an intake.

Abstract: A separator including a full-casing centrifuge and detachably mounted settler tank for solids which run off under action of gravity after centrifuge phase. An inlet for mixture to be separated is located in top of settler tank. A pump with suction tube which extends into settler tank is connected by a line to centrifuge inlet port and conveys all liquid arising, from which at least great particles have already settled out into centrifuge.

Abstract: An apparatus and method for the separation of a predetermined type of microscopic unit (e.g., islets of Langerhans) from a given medium (e.g., pancreatic digest) by centrifuging in a substantially continuous density gradient. In one embodiment, a substantially continuous density gradient solution is provided to a flexible processing bag appropriately positioned within an upper chamber of a rotating variable volume centrifuge. The solution having a plurality of the desired microscopic units therein is loaded onto the gradient and such units migrate to a particular radial position within the gradient based upon the density of such units. Once appropriately separated by the formation of regions, a fluid is provided to a lower chamber of the centrifuge bowl during continued rotation thereof to sequentially remove fractions from the processing bag from an inward location to an outward location, at least one of which fractions includes the band of the desired microscopic units.

Abstract: An apparatus and method for the separation of a predetermined type of microscopic unit (e.g., islets of Langerhans) from a given medium (e.g., pancreatic digest) by centrifuging in a substantially continuous density gradient. In one embodiment, a substantially continuous density gradient solution is provided to a flexible processing bag appropriately positioned within an upper chamber of a rotating variable volume centrifuge. The solution having a plurality of the desired microscopic units therein is loaded onto the gradient and such units migrate to a particular radial position within the gradient based upon the density of such units. Once appropriately separated by the formation of regions, a fluid is provided to a lower chamber of the centrifuge bowl during continued rotation thereof to sequentially remove fractions from the processing bag from an inward location to an outward location, at least one of which fractions includes the band of the desired microscopic units.

Abstract: In a centrifuge for the separation of solids from liquid in which concentrated solids are discharged from radial nozzles at the periphery, there is provided an concentrated solids underflow discharge control apparatus which senses an increased concentration of solids in the underflow and adjusts the flow of the recycle stream as a result thereof to prevent solids from spilling over into the effluent overflow. A sensing chamber and a control module having a flow interference device is utilized to measure a set level backup. Any alteration of said level is detected by a level sensor which sends a signal to a level indicator control and in turn controls the opening and closing of a recycle line valve which controls underflow.

Abstract: A method of processing a highly viscous material comprises the steps of spinning the material in a homogenizer to reduce it to a creamy fluent consistency, flowing the creamy material wholly by gravity down into an upper centrifuge stage, centrifuging the creamy material in the upper centrifuge stage into a solids fraction and a liquid fraction, flowing the solids fraction wholly by gravity down into a lower centrifuge stage, and centrifuging the solids fraction in the lower centrifuge stage. These steps can all take continuously with the material being fed in at one end and the solid and liquid fractions obtained at the opposite lower end. Prior to spinning the material a liquid is added to it to reduce its viscosity and increase its homogeneity. This liquid can be the recirculated liquid fraction obtained in the first centrifuge stage. In accordance with this invention the recirculated liquid fraction is heated to 40.degree. C. to 70.degree. C. before introducing it into the homogenizer.

Abstract: Multi-Stage centrifugal extractors for separating two liquids of differing densities wherein each stage includes a decantation chamber which surrounds and receives liquids from a mixing chamber and wherein a portion of at least one of the separated liquids is recycled from the decantation chamber to the mixing chamber at each stage.

Abstract: A centrifugal extractor for making liquid-liquid extraction by bringing an organic phase and an aqueous phase into mutual contact and utilizing centrifugal force. A rotor rotating at a high speed is disposed inside a cylindrical casing having inlets for both phases. Draw ports for both phases are disposed at an upper portion of the rotor. An organic phase/aqueous phase mixture mixed at the bottom of the casing enters the rotor from the bottom of the rotor, and is subjected to phase separation by centrifugal force. The separated phases are withdrawn from respective draw ports. Part of the organic phase discharged from the organic phase draw port is refluxed to the bottom of the casing by a reflux cover fitted to the upper part of the rotor. The flow rate of the organic phase thus refluxed is added to the flow rate of the organic phase introduced from outside into the casing.

Abstract: A centrifuge drum for concentrating suspended solids, which are conveyed through channels out of an outer solids space in the drum and into a radially inner peeling chamber, whence they are diverted by a peeler and by an associated concentrate line. A separated clear phase is continuously extracted from the interior of the drum by another peeler and by an associated clear-phase line. The object is to prevent the concentrated solids from heating up undesirably even when their volume is small. There is an opening-and-closing communicating line between the concentrate line and the clear-phase line and an opening-and-closing recirculation line extending into the first peeling chamber from the clear-phase line. The communicating line and the recirculation line are closed to divert the solids and opened to discontinue the diversion.

Abstract: Red blood cells being salvaged are centrifuged into a liquid layer, mixed with a wash solution, and thereafter separated therefrom.

Abstract: A system for continuously esparating lighter and intermediate density matter, such as plasma rich in platelets from whole blood moves blood through a diverging centrifugation gap between inner and outer walls of a rotor rotating about a central axis within an outer housing. The centrifugation action creates layered flow along an intermediate section. However by crating trailing wakes in the gap between the rotor and housing, localized remixing patterns tending to move in the opposite direction are induced in the layered matter. Platelet rich plasma may then be extracted through adjacent platelet concentrate ports on the inner wall of the rotor. An interior passageway system passes the platelet rich plasma to a platelet concentrate reservoir. Recirculation of blood in the rotor-housing gap between the output and input, and pumping action provided by the diverging centrifugation gap, aid in enhancing throughput and concentration levels.

Abstract: A liguid separation system includes a first separator unit, a second separator unit and means including a pump for flowing a liquid mixture from a system inlet to the inlet of the first separator unit. A first outlet of the first separator unit is connected to the inlet of the second separator unit, a second outlet of said second separator unit is connected to the inlet of the first separator unit, a first outlet of the second separator unit is connected to a system outlet, and feedback means is adapted to provide continuous flow during system operation of at least about 0.01 gallon per minute from a second outlet of the second separator unit to the inlet of the first separator unit.

Abstract: A system for continuously separating lighter and intermediate density matter, such as plasma rich in platelets from whole blood moves blood through a diverging centrifugation gap between inner and outer walls of a rotor rotating about a central axis within an outer housing. The centrifugation action creates layered flow along an intermediate section. However by crating trailing wakes in the gap between the rotor and housing, localized remixing patterns tending to move in the opposite direction are induced in the layered matter. Platelet rich plasm may then be extracted through adjacent platelet concentrate ports on the inner wall of the rotor. An interior passageway system passes the platelet rich plasma to a platelet concentrate reservoir. Recirculation of blood in the rotor-housing gap between the output and input, and pumping action provided by the diverging centrifugation gap, aid in enhancing throughput and concentration levels.

Abstract: A cascade formed of a plurality of centrifugal contactors useful for countercurrent solvent extraction processes such as utilizable for the reprocessing of nuclear reactor fuels is modified to permit operation in the event one or both end stages of the cascade become inoperative. Weir assemblies are connected to each of the two end stages by suitable conduits for separating liquids discharged from an inoperative end stage based upon the weight of the liquid phases uses in the solvent extraction process. The weir assembly at one end stage is constructed to separate and discharge the heaviest liquid phase while the weir assembly at the other end stage is constructed to separate and discharge the lightest liquid phase. These weir assemblies function to keep the liquid discharge from an inoperative end stages on the same weight phase a would occur from an operating end stage.

Abstract: A self-contained liquid vapor purging system for use in such electromotive apparatus as integrated drive generators, or the like, which include a casing and a rotatable shaft extending into the casing. A charge pump circuit communicates with the casing for circulating liquid from the casing and charging liquid back to the casing. An aspirator is located in the charge pump circuit between a charge pump and an inlet to the casing for mixing fresh air with the liquid to deliver an air-liquid mixture to the casing. A centrifugal separator and check valve are incorporated in the rotatable shaft for separating liquid and vapor. The separator includes a vapor-liquid inlet from the casing, a liquid outlet to the casing, and a vapor outlet draining outside the casing. The centrifugal separator includes a centrifugal valve in communication with the vapor outlet for opening only at a predetermined rotary speed of the shaft.

Abstract: In a previously known centrifugal separator the separation chamber (4) of the centrifuge rotor has an inlet (9) for a mixture of two liquids and relatively heavy solids, a central outlet (23a) for separated light liquid and a periphery outlet (12) for separated solids. A third outlet (35) from the separation chamber (4), situated radially between the first said two outlets (23a, 12), communicates with a recirculation channel, which extends partly through a stationary structure and through which liquid may be conducted from the separation chamber (4) through a sensing device (38) and back to said inlet (9) for mixture. The sensing device (38) is arranged to initiate opening of the periphery outlet (12), when a certain amount of heavy liquid has been separated in the separation chamber (4). A throttle is arranged for limiting of the flow through the recirculation channel.

Abstract: A fuel cell power system for use in a weightless environment, such as in space, includes a device for removing water from a water-hydrogen mixture condensed from the exhaust from the fuel cell power section of the system. Water is removed from the mixture in a centrifugal separator, and is fed into a holding, pressure operated water discharge valve via a Pitot tube. Entrained nondissolved hydrogen is removed from the Pitot tube by a bleed orifice in the Pitot tube before the water reaches the water discharge valve. Water discharged from the valve thus has a substantially reduced hydrogen content.

Abstract: Commercial wide size distribution powders are size classified into precise size fractions by means of a controlled, semi-continuous, multi-stage centrifugal classification system. The system has utility for a wide range of colloidal materials. The throughput of the semi-continuous process is higher than that of batch processes, and the semi-continuous process produces narrow size ranges and optimum yields.

Abstract: A centrifuge system for removing impurities from metal working coolant. The centrifuge of the system includes a liquid inlet, a first liquid outlet for high density liquid, a second liquid outlet for low density liquid, a discharge means for a shoot of particulate material, and a pressure port for receiving liquid under pressure to cause the shoot. A line receives high density liquid from the first liquid outlet. The line discharges into a tank. A branch line connects the line to the pressure port. A valve in the line can stop flow to the tank. When the valve is closed, pressure at the pressure port is increased to cause the shoot.

Abstract: A decanter centrifuge is equipped with a conventional screw conveyor which advances separated solids or heavy phase material toward a solids discharge zone, and it is also equipped with discharge nozzles mounted on the bowl wall for discharging concentrated solids therethrough from the solids discharge zone. In addition to light phase or liquid discharge means, the centrifuge is further provided with a recycle system which returns at least a portion of the discharged solids to the solids discharge zone via a conduit. At the end of the conduit are recycle tubes mounted on the hub of the screw conveyor. The effect of feeding recycled solids to the discharge zone, to which newly separated solids is also being advanced, is to increase the solids concentration of the solids being discharged by the discharge nozzles.

Abstract: In connection with recirculation of separated sludge to the separation chamber of a centrifuge separator there are normally flow restricting nozzles in the sludge outlets of the separation chamber. Only after all separated sludge has passed through these nozzles it is divided into one discharge flow and one recirculation flow.The invention concerns a centrifugal separator with a recirculation circuit (27, 28, 33, 39, 41, 43, 32, 30, 29) for separated sludge, which is completely free of flow restricting nozzles. The amount of separated sludge, that is allowed to leave the centrifugal separator through the outlet conduit (39) without being recirculated, is determined by setting of valves (22, 40) in the stationary outlet conduits (21, 39) for sludge and clarified liquid, respectively.

Abstract: A process and apparatus for infinitely variably setting the U.sup.235 tails concentration in the operation of centrifuge cascades for the separation of the uranium isotopes in a gaseous uranium isotope mixture, comprising introducing a cascade feed comprising a mixture of gaseous uranium isotopes containing U.sup.235 into a feed header of an intermediate stage, equalizing the pressure in the feed header of each stage to the pressure of the cascade feed, and maintaining a predetermined U.sup.235 product concentration by manipulating a choke valve on product or tails streams from each stage, or a choke valve on the cascade feed stream to vary the ratio between the cascade feed and the cascade product stream to adjust the U.sup.235 concentration and the tails.

Abstract: A centrifugal separator comprising a circular centrifuge separation channel having an inlet for receiving a liquid to be separated and an outlet for providing components of the liquid in separated layers at different radial locations, a collection chamber for receiving the separated layers, the chamber having first, second and third outlets in the collection chamber for removing components at different radial locations in the chamber, the first and second collection tubes being joined together so that the combined flow of the two tubes flows in a combined collection tube, and pumps connected to receive liquid streams from the combined collection tube and the third collection tube, the pumps being located externally of, and not rotating with, the channel and collection chamber.

Abstract: In centrifuges for separating solids-liquid slurries and which discharge concentrated solids through nozzles at the periphery of the centrifugal bowl or rotor, it is necessary to maintain a feed or influent rate at least as great as the nozzle discharge rate. According to the present invention, this is accomplished by driving from the centrifuge drive train a pumping means for returning concentrated solids from the nozzles to the centrifuge for recycling through the bowl.

Abstract: An improved desludging device for basket centrifuges facilitates the automatic withdrawal of hard sludge from the centrifuge. The device includes a sludge discharge tube and a sludge re-slurrying tube, the tubes being connected in a loop, so that fluid exiting the centrifuge through the discharge tube reenters the centrifuge through the re-slurrying tube. The re-slurrying tube terminates in one or more nozzles or slots, pointed in the general direction of the discharge tube. This continual recirculation of fluid causes the hard sludge in the centrifuge to return to the form of a slurry, and the slurry is periodically withdrawn from the centrifuge. The re-slurrying effect may be enhanced by the occasional introduction of some process liquid, or other liquid, into the centrifuge. The sludge discharge tube and re-slurrying tube are mechanically linked, and are programmed to move towards the rim of the centrifuge until substantially all the sludge is removed.