US3085743A - Sludge discharging centrifugal separators - Google Patents

Sludge discharging centrifugal separators Download PDF

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Publication number
US3085743A
US3085743A US787309A US78730959A US3085743A US 3085743 A US3085743 A US 3085743A US 787309 A US787309 A US 787309A US 78730959 A US78730959 A US 78730959A US 3085743 A US3085743 A US 3085743A
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United States
Prior art keywords
chamber
sleeve valve
closure
opening
bowl
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US787309A
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English (en)
Inventor
Steinacker Peter
Hemfort Heinrich
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WESTPHALIA SEPARATOR AG
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WESTPHALIA SEPARATOR AG
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
    • B04B—CENTRIFUGES
    • B04B1/00—Centrifuges with rotary bowls provided with solid jackets for separating predominantly liquid mixtures with or without solid particles
    • B04B1/10—Centrifuges with rotary bowls provided with solid jackets for separating predominantly liquid mixtures with or without solid particles with discharging outlets in the plane of the maximum diameter of the bowl
    • B04B1/14—Centrifuges with rotary bowls provided with solid jackets for separating predominantly liquid mixtures with or without solid particles with discharging outlets in the plane of the maximum diameter of the bowl with periodical discharge
    • B04B1/16—Centrifuges with rotary bowls provided with solid jackets for separating predominantly liquid mixtures with or without solid particles with discharging outlets in the plane of the maximum diameter of the bowl with periodical discharge with discharging outlets controlled by the rotational speed of the bowl
    • B04B1/18—Centrifuges with rotary bowls provided with solid jackets for separating predominantly liquid mixtures with or without solid particles with discharging outlets in the plane of the maximum diameter of the bowl with periodical discharge with discharging outlets controlled by the rotational speed of the bowl controlled by the centrifugal force of an auxiliary liquid

Definitions

  • Centrifugal separators which have bowls from which accumulated sludge may be periodically discharged are known. These separators may have a centrifugal bowl with peripheral sludge discharge openings which may be opened and closed by an axially movable sleeve valve.
  • the sleeve valve may be hydraulically operated in one or both directions.
  • the bowl may have a bottom insert which forms the bottom surface of the bowl interior.
  • This bottom insert has a lower surface positioned in spaced relationship to the upper surface of the bottom portion of the bowl casing.
  • the sleeve valve has an inwardly extending flange or plate which is positioned in this space and divides the same into an upper opening chamber and a lower closing chamber.
  • the control is effected by introducing a control liquid such as water into the opening chamber above the flange, or into the closure chamber below the flange. Due to the centrifugal force of the rotating bowl, the liquid acts under pressure in these chambers. There is, thus, produced in one of the two chambers an excess pressure which effects the downward or upward movement of the sleeve valve whereby the sludge discharge openings are exposed or closed.
  • both chambers are filled independently of each other with control liquid through channels or holes while in other embodiments, the chambers have a common feed channel.
  • the opening chamber may have small discharge conduits at its outer periphery through which the control liquid may leave the chamber.
  • more control liquid is introduced into the opening chamber than can be discharged through its peripheral conduits.
  • the liquid builds up in the opening chamber and a centrifugal pressure head is formed which forces the inwardly extending flange and the sleeve valve downward and displaces the control liquid present in the closure chamber.
  • the control liquid introduced into the opening chamber is throttled or interrupted so that the same may discharge through the peripheral conduits.
  • control liquid at the same time is allowed to build up in the closure chamber so that the pressure of the centrifugal head in this chamber exceeds that in the opening chamber and the sleeve valve is moved upwardly to close the sludge discharge openings.
  • water is used as the control liquid.
  • a further disadvantage of conventional sludge discharge centrifugal separators is the fact that the opening of the sludge discharge outlets often takes place too slowly. This occurs because the mass in the closure chamber is somewhat inwardly displaced upon moving the sleeve valve to opened position, increasing the working surface area of said sleeve valve as it so moves. Further more, an increase in countcrpressure results in the closure chamber acting to retard the opening of said valve, necessitating additional filling of the opening chamber and an increase in the filling time. These actions delay rapid opening of conventional sludge discharge outlets.
  • the rinsing liquid fed to the drum for removing the sludge may break through the cake of solids formed along the separator wall during sludge separation, thereby causing any advantageous pressure build-up to be lost. Under these conditions, the solids may be only partially expelled so that strong imbalances of the rotating drum may occur.
  • FIG. 1 shows an embodiment of a centrifuge in accordance with the invention, with the sleeve valve in the closed position, and
  • the centrifugal separator in accordance with the invention, has a closure chamber developed as a storage chamber which will not force all of the material used for effecting the closing actuation therefrom even when the sleeve valve is in the open position. At least a predetermined portion of the mass which is flowable or deformable under centrifugal force is permanently contained in the closure chamber.
  • This mass for example, may consist of a liquid which does not evaporate even at increased temperature or a plastic or elastic mass.
  • the closure chamber should be outwardly sealed, but may he provided with an opening in its end portion a predetermined distance from the axis of rotation of the centrifuge through which the centrifugally deformable closure material may be introduced and from which the excess of this material over the predetermined amount desired may be discharged upon the first sludge removal.
  • the inwardly extending flange which is connected to the sleeve valve preferably extends to adjacent the hub of the centrifugal bowl so that the opening liquid may exert a force on a larger area than in previously known embodiments.
  • the closure material furthermore, acts in the open position of the sleeve valve on a larger area than in the closed position. Thus, this material will exert a larger force at the beginning of the upward movement of the valve where it is needed to overcome the starting friction.
  • the effective surface area on which the closing deformable mass may exert its force is considerably diminished in the peripheral portion of the closure chamber farthest from the axis of rotation, that is, where the force of said mass is greatest, upon moving the sleeve valve to opened position, while the remaining effective surface area as aforesaid is only slightly increased in a direction towards the axis because of such annular e'xtension. Consequently, upon movement of the sleeve valve into opened position, as when liquid is conducted to the opening chamber in conventional manner, the counteracting force of the deformable or flowable mass in the closure chamber is considerably less than that exerted in conventional separators, permitting speedy movement of the sleeve valve from closed to opened position.
  • Constructions in accordance with the present invention therefore, favorably provide for the etlicient and rapid opening and closing of the sludge discharge openings, utilizing the centrifugal force of the separator to advantage. Specifically, the cake of solids deposited in the drum during separation of the sludge from the accompanying liquid will be completely discharged from the drum under the pressure of the rinsing liquid, eliminating any possible imbalancing of the drum, since the sleeve valve is quickly moved into opened position.
  • one or more limiting exit tubes or channels connecting said closure chamber with the outside are provided whereby a given quantity of said mass will always be present in said chamber.
  • These tubes project into said chamber a predetermined distance, or are positioned at a point in the chamber wall a given distance from the axis, so that a sufficient quantity of tlowable mass will always be present in said closure chamber.
  • deformable or flowable mass materials which may be used in accordance with the invention are any flowable plastic and elastic materials, any deformable plastic and elastic materials, water, and water-based deformable or llowable materials, all of said materials being capable of deforming or flowing under centrifugal force and preferably being liquid.
  • the present invention advantageously provides a closure chamber in centrifugal separators having a widened annular space portion into which the deformable or llowable mass may be directed during movement of the sleeve valve into opened position with only a slight increase in working surface area in a radially inward direction. Furthermore, the invention provides such a closure chamber having a varying volume peripheral portion in which the working surface area decreases during movement of the sleeve valve to opened position correspondingly decreasing the force of the flowable or deformable mass thereat, and increases during movement. of said valve to closed position correspondingly increasing the force of said mass thereat.
  • the closure chamber construction of the invention enables the sleeve valve to respond rapidly to open and close the sludge discharge openings, due to the immediate decrease in the force of the fiowable or deformable mass upon moving said sleeve valve to opened position and the immediate increase in the force of said mass upon moving said sleeve valve to closed position, respectively.
  • the centrifugal bowl' is composed of the lower casing part 1 and the upper casing part or cover part 2, which are connected to each other by means of the locking ring 3.
  • the bowl is mounted for rotation with the spindle 28 in the conventional manner.
  • the bowl casing is provided with peripheral sludge discharge openings or ports 20.
  • a sleeve valve 21 is axially movable within the bowl between a position shown in FIG. 1 of the drawing in which its upper edge contacts the gasket 22 and seals the discharge openings Ztl and a lower position shown in FIG. 2 of the drawing in which its upper edge is in spaced relationship to the gasket 22 opening the sludge discharge openings 20.
  • a bottom insert member 6 defines the lower surface of the bowl interior and is spaced from the bottom 5 of the bowl casing to define a free space therebetween.
  • the distributor 4 which extends axially upward to the central portion of the bowl is formed as an integral portion of the bottom insert member 6. This distributor distributes material introduced into the centrifuge through the conduit 19 in the bowl through the conduit 23.
  • the bottom insert member 6 has an outer annular guide surface 8 which acts as a sliding guide for the sleeve valve 21.
  • a flange 10 is connected to the lower portion of the sleeve valve 21 as an integral part thereof and moves therewith. This flange 10 extends inwardly and divides the free space between the member 6 and bottom 5 into an upper opening chamber 12 and a lower closure chamber 11. The inner end of the flange terminates as a guide surface 9, which slides in contact with the hub of the centrifugal drum.
  • the lower closure chamber 11 is formed as an outwardly confined storage space which is dimensioned for maintaining at least a given quantity of deformable or fiowable material such as liquid, plastic or elastic material therein at any position of movement of the sleeve valve 21 and the flange 10.
  • a control liquid such as water may be introduced into the upper opening chamber 12 through the conduits 16 and 17. Liquid may be removed from this chamber by centrifugal action through the outlet conduit 13 in the sleeve valve 21 and the port 14.
  • the centrifugal bowl is rotated with the spindle 28 in the conventional manner.
  • the material to be treated is introduced through the inlet pipe 19 and passes through the distributor 4 and conduit 23 into the interior of the bowl which contains the conventional disc inserts 24.
  • the lighter liquid passes inwardly over the disc insert and is discharged over the overflow lip 25.
  • the heavier liquid is forced by the centrifugal force outwardly and passes upward and is discharged over the overflow lip 26.
  • Solid materials or the like, designated as sludge accumulate at the peripheral portion 7 of the bowl interior.
  • a closure liquid having a high boiling point or a plastic or elastic material is introduced into the closure chamber 11 in amount at least suflicient to fill the chamber to the level 15 indicated in FIG. 1 of the drawing during the centrifuging with the sleeve valve 21 in the closed position.
  • the deformable material is forced outwardly by the centrifugal action and forces the flange 10 and the sleeve valve 21 upward in the closed position.
  • water or similar control liquid is introduced through the pipe 16 and conduit 17 into the opening chamber 12.
  • the amount of water introduced should exceed the amount which is forced out by the centrifugal action through the opening 13 and port 14.
  • a centrifugal head of water thus builds up in the opening chamber 12. When this head builds up so that a pressure is formed which exceeds the pressure in the closure chamber 11, the flange 10 and sleeve valve 21 are forced downwardly to the position indicated in FIG. 2 of the drawing. The centrifugal pressure within the bowl can then force the sludge out through the annular space between the upper edge of the valve 21 and the gasket 22 and through the discharge openings 20.
  • any excess of the deformable closure material which has been introduced into the closure chamber 11, as, for example, upon assembly thereof may discharge through the opening 18 or 180 upon the first opening actuation of sleeve valve 21.
  • the closure chamber 12 When the closure chamber 12 is filled with water, it is difficult to prevent small amounts of Water from leaking out along the guide surface 9.
  • a small ring chamber 29 is provided below the guide surface 9. Any water leaking through the guide surface will therefore accumulate in this ring chamber.
  • a drain conduit 27 is provided from the ring chamber through which the water may pass out.
  • the closure chamber 11 is formed as a storage space, and is closed off to prevent entrance of control liquid from the opening chamber, the deformable mass may remain as a substantially permanent part of the apparatus within the closure chamber without subsequent additions, etc.
  • the opening and closing are completely actuated by passing the control liquid into the opening chamber and by allowing the same to flow out therefrom.
  • closure chamber 11 is provided with a widened annular space 30, which receives a substantial portion of the deformable or fiowable mass which is displaced from the peripheral portion of chamber 11 upon movement of sleeve valve 21 to opened position as shown in FIG. 2.
  • a shift in the level of said mass from that indicated at 15 in H6. 1 to that indicated at 15:: in FIG. 2 therefore takes place.
  • pro jection tube 18 in the bottom surface of bowl casing S of FIG. 1, or channel tube 180 in sleeve valve 21 communicating with port 14 of P16. 2 with respect to the desired level of deformable or flowable mass disposed in closure chamber 11, said mass will not pass out of said chamber under centrifugal action except to the limit de fined by tube 18 or 18a.
  • the level of the flowablc material is shown radially outwardly at level 15, the flowable material occupying the peripheral portion of the closing chamber 11 when no control liquid is passed through conduits 16 and 17 to the opening chamber 12.
  • the level of the flowable material is determined radiullyinwardly by the presence of tube 18:: which allows excess flowable material to pass off from closing chamber 11 through tube 18a and port 14.
  • tube 18 which allows excess flowable material to pass off from closing chamber 11 through tube 18a and port 14.
  • the portion of Working surface increased by the radially inward displacement of the flowable material from the level 15 to the level will only insignificantly compensate for the loss of working surface due to the peripheral abutting engagement of the bottom surface of flange 10 and the corresponding surface of bottom 5 of the casing.
  • the movement of flange 10 from closing position to opening position will decrease the volume of closing chamber 11, at the same time decreasing the effective flowable material working surface area within closing chamber l1. Accordingly, since a decreased Working surface area is involved, the flange 10 will immediately respond to control liquid passed to opening chamber 12 and rapidly and abruptly open the discharge ports for the effective discharge of sludge from the drum.
  • a centrifugal separator having a centrifugal bowl with peripheral sludge discharge openings and an axially movable sleeve valve, movable between a position opening and a position closing said sludge discharge openings, the improvement which comprises an insert member defining an end surface of the bowl interior and positioned to define a free space between it and the adjacent wall portion of the how], a flange connected to said sleeve valve for movement therewith extending inwardly within said free space dividing the same into an opening chamber and a closure chamber, means for introducing liquid into said opening chamber during centrifugal operation to move said sleeve valve to opening position and means for the removal of liquid from said opening chamber, said closure chamber containing flowable material therewithin and having means for sealing said closure chamber against the flow and overflow of said material therefrom into said opening chamber and for sealing said closure chamber against the complete outward flow of said material therefrom both at standstill and under centrifugal action whereby a given mass of a flowable closure material
  • centrifugal separator having a centrifugal bowl with peripheral sludge discharge openings and an axially movable sleeve valve, movable between a position opening and a position closing said sludge discharge openings
  • the improvement which comprises an insert member defining an end surface of the bowl interior and positioned to define a free space between it and the adjacent wall portion of the bowl, a flange connected to said sleeve valve for movement therewith extending inwardly within said free space dividing the same into an upper opening chamber and a lower closure chamber, said closure chami361 defining by means of said flange and the bowl an outwardly confined adjustable volume storage space dimensioned thereby for the maintaining of a predetermined quantity of flowable material therein undzr centrifugal action and at standstill in any position of movement of said sleeve valve and in turn said flange, said flange substantially completely sealing said closure chamber from flow communication with said opening chamber, an elastic flowable material positioned in said closure chamber and means for introducing liquid into said opening chamber during centrifugal operation to move said sleeve valve to opening position and means for the removal of liquid from said opening chamber, said adjustable volume storage space having, when said sleeve valve is in closing position, a radi
  • a centrifugal separator having a centrifugal bowl with peripheral sludge discharge openings and an axially movable sleeve valve, movable between a position opening and a position closing said sludge discharge openings
  • the improvement which comprises an insert member defining an end surface of the bowl interior and positioned to define a free space between it and the adjacent wall portion of the bowl, a flange connected to said sleeve valve for movement therewith extending inwardly within said free space dividing the same into an opening chamber and a closure chamber, said closure chamber defining by means of said flange and the bowl an outwardly confined storage space adjustable in volume in dependence upon the movement of said flange, containing a flowable material therewithin and being peripherally and annularly dimensioned thereby for permanently maintaining at least a predetermined amount of said flowable material therein under centrifugal action and at standstill in any position of movement of said sleeve valve and in turn said flange, said flange substantially completely
  • a tubular extension communicating with the exterior of said separator projects a predetermined distance into said closure chamber a predetermined distance from the periphery of said closure chamber and axially above a predetermined level of said fiowable material in said closure chamber when said separator is at standstill, whereby complete outward fiow of said fiowable closure material will be prevented and a given mass of said material will be maintained therein in any said position of movement of said sleeve valve.
  • a tubular extension communicating with the exterior of said separator projects a predetermined distance into said closure chamber a predetermined distance from the periphery of said closure chamber and axially above a predetermined level of said fiowable material in said closure chamber when said separator is at standstill, whereby complete outward flow 0t said flowable closure material will be prevented and a given mass of said material will be maintained therein in any said position of movement of said sleeve valve.

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  • Centrifugal Separators (AREA)
US787309A 1954-02-11 1959-01-16 Sludge discharging centrifugal separators Expired - Lifetime US3085743A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DEW13231A DE1000292B (de) 1954-02-11 1954-02-11 Schleudertrommel mit Schlammaustrittoeffnungen
DEW23096A DE1055451B (de) 1954-02-11 1958-04-05 Schleudertrommel mit Schlammaustrittoeffnungen

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US3085743A true US3085743A (en) 1963-04-16

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US787309A Expired - Lifetime US3085743A (en) 1954-02-11 1959-01-16 Sludge discharging centrifugal separators

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US (1) US3085743A (xx)
CH (1) CH325206A (xx)
DE (2) DE1000292B (xx)
FR (1) FR1118616A (xx)
GB (2) GB764631A (xx)
NL (2) NL237164A (xx)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3167509A (en) * 1961-06-13 1965-01-26 Westfalia Separator Ag Centrifugal separator
US3189267A (en) * 1960-04-20 1965-06-15 Separator Ab Sludge centrifuge
US3193194A (en) * 1961-06-26 1965-07-06 Westfalia Separator Ag Centrifugal separator bowl with periodically operated sludge discharge means
US3360194A (en) * 1965-01-25 1967-12-26 Westfalia Separator Ag Apparatus and method for automatic overload protection in centrifuge equipment
US3415446A (en) * 1967-04-11 1968-12-10 Carl W. Weiland Hydraulically actuated valve plate for a centrifuge
US20040178127A1 (en) * 2003-03-12 2004-09-16 Westfalia Separator Ag Centrifugal drum for a separator
US11000859B2 (en) 2019-05-21 2021-05-11 Empirical Innovations, Inc. Drum and ejection control arrangements for centrifugal separators and separation methods employing multiple pistons to control separate intermittent ejection of heavy and intermediate material

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DK98680C (da) * 1958-04-05 1964-05-04 Westfalia Separator Ag Centrifugetromle med slamudløbsåbninger ved omkredsen.
GB1084599A (en) * 1964-10-15 1967-09-27 Asahi Chemical Ind Process for the preparation of unsaturated aliphatic nitriles
GB1591811A (en) * 1977-05-24 1981-06-24 Jackson J F Desludger type disc bowl centrifuges

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US878591A (en) * 1907-01-25 1908-02-11 Karl Abel Switch device.
US957347A (en) * 1909-09-02 1910-05-10 Nat Carbonated Liquid Co Combined stuffing-box, gasket, valve, and spring.
US2103822A (en) * 1936-01-14 1937-12-28 Ira D Perry Tire valve and the like
GB616442A (en) * 1945-09-15 1949-01-21 Separator Ab Improvements in centrifugal separators

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR715701A (fr) * 1931-04-20 1931-12-08 Separator Ab Séparateur avec évacuation intermittente des boues ou impuretés
GB492736A (en) * 1935-12-24 1938-09-26 Separator Ab Process and apparatus for the separation of solid matter from liquids

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US878591A (en) * 1907-01-25 1908-02-11 Karl Abel Switch device.
US957347A (en) * 1909-09-02 1910-05-10 Nat Carbonated Liquid Co Combined stuffing-box, gasket, valve, and spring.
US2103822A (en) * 1936-01-14 1937-12-28 Ira D Perry Tire valve and the like
GB616442A (en) * 1945-09-15 1949-01-21 Separator Ab Improvements in centrifugal separators

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3189267A (en) * 1960-04-20 1965-06-15 Separator Ab Sludge centrifuge
US3167509A (en) * 1961-06-13 1965-01-26 Westfalia Separator Ag Centrifugal separator
US3193194A (en) * 1961-06-26 1965-07-06 Westfalia Separator Ag Centrifugal separator bowl with periodically operated sludge discharge means
US3360194A (en) * 1965-01-25 1967-12-26 Westfalia Separator Ag Apparatus and method for automatic overload protection in centrifuge equipment
US3415446A (en) * 1967-04-11 1968-12-10 Carl W. Weiland Hydraulically actuated valve plate for a centrifuge
US20040178127A1 (en) * 2003-03-12 2004-09-16 Westfalia Separator Ag Centrifugal drum for a separator
US7331919B2 (en) * 2003-03-12 2008-02-19 Westfalia Separator Ag Centrifugal drum for a separator
US11000859B2 (en) 2019-05-21 2021-05-11 Empirical Innovations, Inc. Drum and ejection control arrangements for centrifugal separators and separation methods employing multiple pistons to control separate intermittent ejection of heavy and intermediate material

Also Published As

Publication number Publication date
GB764631A (en) 1956-12-28
CH325206A (de) 1957-10-31
DE1055451B (de) 1959-04-16
GB858617A (en) 1961-01-11
FR1118616A (fr) 1956-06-08
DE1000292B (de) 1957-01-03
NL237164A (xx)
NL103671C (xx)

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