EP0631820A2 - Process for operating a screw centrifuge - Google Patents
Process for operating a screw centrifuge Download PDFInfo
- Publication number
- EP0631820A2 EP0631820A2 EP94107900A EP94107900A EP0631820A2 EP 0631820 A2 EP0631820 A2 EP 0631820A2 EP 94107900 A EP94107900 A EP 94107900A EP 94107900 A EP94107900 A EP 94107900A EP 0631820 A2 EP0631820 A2 EP 0631820A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- centrifuge
- screw
- speed
- centrifuge drum
- screw conveyor
- Prior art date
- 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.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims description 8
- 239000007788 liquid Substances 0.000 claims abstract description 31
- 239000000126 substance Substances 0.000 claims description 19
- 238000000926 separation method Methods 0.000 claims description 6
- 239000000463 material Substances 0.000 claims description 5
- 239000008247 solid mixture Substances 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 3
- 239000007787 solid Substances 0.000 abstract description 3
- 230000005484 gravity Effects 0.000 abstract 1
- 230000000694 effects Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
Images
Classifications
-
- 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
- B04B1/20—Centrifuges with rotary bowls provided with solid jackets for separating predominantly liquid mixtures with or without solid particles discharging solid particles from the bowl by a conveying screw coaxial with the bowl axis and rotating relatively to the bowl
- B04B1/2016—Driving control or mechanisms; Arrangement of transmission gearing
Definitions
- the invention is directed to a method for operating screw centrifuges for the separation of liquid-solid mixtures, consisting of a centrifuge drum which is rotatably mounted about its longitudinal axis and which surrounds a coaxially arranged screw conveyor rotating at a different speed (leading or lagging) Screw spirals are attached to a screw drum, whereby means for feeding the mixture to be separated into the centrifuge drum along its axis and at opposite ends of the centrifuge drum are provided openings for the discharge of the separated light and heavy materials, the radial distance of which from the centrifuge drum shaft axis is less than that Distance of the centrifuge drum wall from the centrifuge drum axis, so that a liquid ring forms within the centrifuge drum during operation of the screw centrifuge under the influence of the centrifugal force.
- the heavy materials are gripped by the screw spirals of the screw conveyor, which, depending on the direction of rotation of the centrifuge, is set behind or ahead of the speed of the centrifuge drum in the same direction of rotation, and transported to one end of the centrifuge, where they emerge from the centrifuge through corresponding openings .
- the light substances flow to the opposite end of the centrifuge to the discharge openings arranged there, and at least partially flow through the channels formed from the screw spirals of the screw conveyor counter to the conveying direction of the screw conveyor.
- the object is achieved by the measures of the characterizing part of claim 1.
- Advantageous embodiments of the invention are specified in the subclaims.
- the conveying effect of screw conveyors is based on a speed difference between the screw conveyor and the material to be conveyed, the conveying direction being determined by the direction of rotation and by the direction of the spiral of the screw conveyor.
- the speed of the screw conveyor is greater than the speed of the material to be conveyed, which is rotating with the centrifuge drum, the heavy substances, whereby these are conveyed by the screw conveyor to the end of the centrifuge in accordance with the direction of the spiral.
- the speed of the screw conveyor is lower than the speed of the centrifuge drum (the direction of rotation of the centrifuge bowl and screw conveyor or the direction of the spiral of the screw conveyor is reversed to the screw centrifuge with a leading screw conveyor), so that there is also a transport in this direction to the discharge openings for the heavy substances.
- a known full-shell screw centrifuge (1) in countercurrent design with a leading screw conveyor (4) is shown.
- the liquid-solid mixture to be separated is introduced through the feed device (14) along the axis of rotation into the screw centrifuge (1) and passes through the openings (7) into the separation space formed by the centrifuge drum (2) and the screw drum (13). Due to the centrifugal force acting on the introduced mixture and the separation taking place, a liquid ring is formed, the outer diameter of which corresponds to the inner diameter of the centrifuge drum (2) and the inner diameter of which is determined by the position of the weir (8) of the discharge opening (5) for the light substances ( Liquid) is given and corresponds to the broken line (9) in the drawing.
- the measure according to the invention thus successfully prevents liquid from also being discharged at the discharge opening (6) for the heavy substances (10) when the liquid ring collapses.
- the invention is not only limited to the embodiment of a countercurrent screw centrifuge shown in the drawing figure, but also to other screw centrifuges, e.g. B. DC screw centrifuges, screen screw centrifuges etc. applicable, the conveyor screws of which are driven at a leading or lagging speed.
- screw centrifuges e.g. B. DC screw centrifuges, screen screw centrifuges etc. applicable, the conveyor screws of which are driven at a leading or lagging speed.
Landscapes
- Centrifugal Separators (AREA)
Abstract
Description
Die Erfindung ist auf ein Verfahren zum Betrieb von Schneckenzentrifugen für die Trennung von Flüssigkeit-Feststoffgemische gerichtet, bestehend aus einer Zentrifugentrommel, die um ihre Längsachse drehbar gelagert ist und die eine koaxial angeordnete, mit abweichender Drehzahl (voreilend oder nacheilend) umlaufende Förderschnecke umschließt, deren Schneckenwendeln auf einer Schneckentrommel befestigt sind, wobei Einrichtungen zum Zuführen des zu trennenden Gemisches in die Zentrifugentrommel längs deren Achse sowie an entgegengesetzten Enden der Zentrifugentrommel Öffnungen für den Austrag der getrennten leichten und schweren Stoffe vorgesehen sind, deren radialer Abstand von der Zentrifugentrommelwellenachse geringer ist als der Abstand der Zentrifugentrommelwand von der Zentrifugentrommelachse, so daß sich beim Betrieb der Schneckenzentrifuge unter dem Einfluß der Zentrifugalkraft innerhalb der Zentrifugentrommel ein Flüssigkeitsring ausbildet.The invention is directed to a method for operating screw centrifuges for the separation of liquid-solid mixtures, consisting of a centrifuge drum which is rotatably mounted about its longitudinal axis and which surrounds a coaxially arranged screw conveyor rotating at a different speed (leading or lagging) Screw spirals are attached to a screw drum, whereby means for feeding the mixture to be separated into the centrifuge drum along its axis and at opposite ends of the centrifuge drum are provided openings for the discharge of the separated light and heavy materials, the radial distance of which from the centrifuge drum shaft axis is less than that Distance of the centrifuge drum wall from the centrifuge drum axis, so that a liquid ring forms within the centrifuge drum during operation of the screw centrifuge under the influence of the centrifugal force.
Bei der Trennung von Flüssigkeit-Feststoffgemische in Schneckenzentrifugen bildet sich unter dem Einfluß der durch die Drehung der Schneckenzentrifuge hervorgerufenen Zentrifugalkraft, die ein mehrfaches der Gravitationskraft ist, innerhalb der Zentrifugentrommel ein Ring aus dem zu trennenden Flüssigkeit-Feststoffgemisch aus, der vorwiegend aus bereits abgetrennter Flüssigkeit besteht und dessen Innendurchmesser durch die radiale Anordnung der Austragsöffnungen für die leichten Stoffe (z. B. der abgetrennten Flüssigkeit) bestimmt ist.When separating liquid-solid mixtures in screw centrifuges, under the influence of the centrifugal force caused by the rotation of the screw centrifuge, which is a multiple of the gravitational force, a ring is formed within the centrifuge drum from the liquid-solid mixture to be separated, which mainly consists of liquid that has already been separated exists and whose inner diameter is determined by the radial arrangement of the discharge openings for the light substances (e.g. the separated liquid).
In diesem Flüssigkeitsring findet unter dem Einfluß der Zentrifugalkraft die Trennung in spezifisch schwere und in spezifisch leichte Stoffe statt, wobei sich die spezifisch schweren Stoffe (die Feststoffe) am äußeren Rand des Ringes, also an der Zentrifugentrommelwand anordnen und die spezifisch leichten Stoffe (die Flüssigkeit) im inneren Bereich des Ringes sich darüber schichten.In this liquid ring, under the influence of the centrifugal force, the separation into specifically heavy and into specifically light substances takes place, whereby the Place specifically heavy substances (the solids) on the outer edge of the ring, i.e. on the centrifuge drum wall and layer the specifically light substances (the liquid) in the inner area of the ring.
Von den Schneckenwendeln der Förderschnecke, die je nach Drehrichtung der Zentrifuge gegenüber der Drehzahl der Zentrifugentrommel nacheilend oder voreilend in gleicher Drehrichtung in Drehung versetzt ist, werden die schweren Stoffe erfaßt und zu einem Ende der Zentrifuge transportiert, wo sie durch entsprechende Öffnungen aus der Zentrifuge austreten. Die leichten Stoffe fließen zum entgegengesetzten Ende der Zentrifuge zu den dort angeordneten Austragsöffnungen, wobei sie durch die aus den Schneckenwendeln der Förderschnecke gebildeten Kanäle zumindest teilweise entgegen der Förderrichtung der Förderschnecke fließen.The heavy materials are gripped by the screw spirals of the screw conveyor, which, depending on the direction of rotation of the centrifuge, is set behind or ahead of the speed of the centrifuge drum in the same direction of rotation, and transported to one end of the centrifuge, where they emerge from the centrifuge through corresponding openings . The light substances flow to the opposite end of the centrifuge to the discharge openings arranged there, and at least partially flow through the channels formed from the screw spirals of the screw conveyor counter to the conveying direction of the screw conveyor.
Beim Abstellen der Zentrifuge verringert sich die Drehzahl der Zentrifuge bis zum Stillstand und damit verringert sich auch die Zentrifugalkraft. Es wird dabei eine Drehzahl erreicht, bei der die Zentrifugalkraft niedriger wird als die Gravitationskraft mit der Folge, daß der in der Zentrifuge sich ausgebildete Flüssigkeitsring "zusammenbricht" und der Füllstand innerhalb der Zentrifuge über die Austragsöffnungen für die schweren Stoffe (Feststoffe) hinausreicht, so daß an diesen Öffnungen - wenn auch nur kurzfristig - schwallartig auch die leichten Stoffe austreten. Hierdurch wird nicht nur das Trennergebnis verschlechtert, sondern es sind auch verfahrenstechnische Störungen bei der weiteren Verarbeitung der schweren Stoffe zu erwarten.When the centrifuge is switched off, the speed of the centrifuge is reduced to a standstill and thus the centrifugal force is also reduced. A speed is reached at which the centrifugal force becomes lower than the gravitational force with the result that the liquid ring formed in the centrifuge "breaks down" and the level inside the centrifuge extends beyond the discharge openings for the heavy substances (solids), so that at these openings - even if only for a short time - the light substances also gush out. This not only worsens the separation result, but also procedural disturbances in the further processing of the heavy substances are to be expected.
Es ist Aufgabe der Erfindung, ein Verfahren zum Betrieb von Schneckenzentrifugen zu schaffen, mit dem ein Abstellen der Zentrifugen bei Vermeidung der oben geschilderten Nachteile ermöglicht wird.It is an object of the invention to provide a method for operating screw centrifuges with which the centrifuges can be switched off while avoiding the disadvantages described above.
Die gestellte Aufgabe wird gelöst durch die Maßnahmen des Kennzeichnungsteils des Anspruchs 1. Vorteilhafte Ausgestaltungen der Erfindung sind in den Unteransprüchen angegeben. Die Förderwirkung von Förderschnecken beruht auf einen Drehzahlunterschied zwischen der Förderschnecke und dem zu fördernden Gut, wobei die Förderrichtung durch die Drehrichtung und durch die Richtung der Wendelung der Förderschnecke bestimmt ist.The object is achieved by the measures of the characterizing part of claim 1. Advantageous embodiments of the invention are specified in the subclaims. The conveying effect of screw conveyors is based on a speed difference between the screw conveyor and the material to be conveyed, the conveying direction being determined by the direction of rotation and by the direction of the spiral of the screw conveyor.
Beim Betrieb von Schneckenzentrifugen mit voreilender Förderschnecke ist die Drehzahl der Förderschnecke größer als die Drehzahl des mit der Zentrifugentrommel umlaufenden Fördergutes, den schweren Stoffen, wodurch diese von der Förderschnecke entsprechend der Richtung der Wendelung zu einem Ende der Zentrifuge gefördert werden.When operating screw centrifuges with a leading screw conveyor, the speed of the screw conveyor is greater than the speed of the material to be conveyed, which is rotating with the centrifuge drum, the heavy substances, whereby these are conveyed by the screw conveyor to the end of the centrifuge in accordance with the direction of the spiral.
Wenn nun beim Abstellen der Zentrifuge, und zwar dann, wenn die Drehzahl der Zentrifugentrommel soweit abgesunken ist, daß das Zusammenbrechen des Flüssigkeitsringes unmittelbar bevorsteht, erfindungsgemäß die Drehzahl der Zentrifugentrommel und/oder der Förderschnecke durch Abbremsen schlagartig verändert wird, d. h. die Zentrifuge wird möglichst schnell stillgesetzt, spielt sich folgender Vorgang innerhalb der Zentrifuge ab:
Der mit der Zentrifugentrommel umlaufende Flüssigkeitsring behält infolge seiner Trägheit zunächst seine Geschwindigkeit bei, ist aber nun schneller als die abgebremste Förderschnecke, wodurch sich die Förderrichtung in Richtung zum anderen Ende der Zentrifuge hin umkehrt.If now when the centrifuge is switched off, specifically when the speed of the centrifuge drum has dropped so far that the collapse of the liquid ring is imminent, the speed of the centrifuge drum and / or the screw conveyor is suddenly changed by braking, that is to say the centrifuge becomes as fast as possible stopped, the following process takes place within the centrifuge:
The liquid ring rotating with the centrifuge drum initially maintains its speed due to its inertia, but is now faster than the decelerated screw conveyor, which reverses the conveying direction towards the other end of the centrifuge.
Wenn der FIüssigkeitsring nun zusammenbricht, "schraubt" sich die Flüssigkeit zu dem Ende der Zentrifuge, an dem die Austragsöffnungen für die leichten Stoffe angeordnet sind, und an den Austragsöffnungen für die schweren Stoffe tritt keine Flüssigkeit aus.If the liquid ring now collapses, the liquid "screws" to the end of the centrifuge at which the discharge openings for the light substances are arranged, and no liquid escapes from the discharge openings for the heavy substances.
Beim Betrieb der Schneckenzentrifuge mit nacheilender Förderschnecke ist die Drehzahl der Förderschnecke kleiner als die Drehzahl der Zentrifugentrommel (die Drehrichtung von Zentrifugentrommel und Förderschnecke oder die Richtung der Wendelung der Förderschnecke verlaufen umgekehrt zur Schneckenzentrifuge mit voreilender Förderschnecke), so daß sich auch hier ein Transport in Richtung zu den Austragsöffnungen für die schweren Stoffe ergibt.When the screw centrifuge is operated with a trailing screw conveyor, the speed of the screw conveyor is lower than the speed of the centrifuge drum (the direction of rotation of the centrifuge bowl and screw conveyor or the direction of the spiral of the screw conveyor is reversed to the screw centrifuge with a leading screw conveyor), so that there is also a transport in this direction to the discharge openings for the heavy substances.
Um die Transportrichtung der Förderschnecke beim Abstellen der Zentrifuge so umzukehren, daß beim Zusammenbrechen des Flüssigkeitsrings auch hier kein Austrag aus den Austragsöffnungen für die schweren Stoffe erfolgt, ist es nun erforderlich, daß der Flüssigkeitsring langsamer umläuft als die Förderschnecke. Erfindungsgemäß wird dies dadurch erreicht, daß die Drehzahl der Zentrifugentrommel und/oder der Förderschnecke kurzfristig nochmals schlagartig erhöht wird, wodurch sich nun auch hier der zusammenbrechende Flüssigkeitsring zu den Austragsöffnungen für die leichten Stoffe "schraubt", da der Flüssigkeitsring aufgrund seiner Trägheit vorerst seine langsame Geschwindigkeit beibehält.In order to reverse the direction of transport of the screw conveyor when the centrifuge is switched off so that when the liquid ring collapses, there is no discharge from the discharge openings for the heavy substances, it is now necessary for the liquid ring to rotate more slowly than the screw conveyor. According to the invention this is achieved in that the speed of the centrifuge drum and / or the screw conveyor is suddenly increased again briefly, as a result of which the collapsing liquid ring now "screws" to the discharge openings for the light substances, since the liquid ring is initially slow due to its inertia Maintains speed.
Weitere Einzelheiten und Merkmale der Erfindung werden anhand eines Anwendungsbeispiels in einer Zeichnungsfigur näher erläutert.Further details and features of the invention are explained in more detail using an application example in a drawing figure.
In der Zeichnungsfigur ist eine an sich bekannte Vollmantelschneckenzentrifuge (1) in Gegenstromausführung mit voreilender Förderschnecke (4) dargestellt. Das zu trennende Flüssigkeit-Feststoffgemisch wird durch die Zuführeinrichtung (14) längs der Drehachse in die Schneckenzentrifuge (1) eingebracht und gelangt durch die Öffnungen (7) in den aus der Zentrifugentrommel (2) und der Schneckentrommel (13) gebildeten Trennraum. Aufgrund der auf das eingebrachte Gemisch wirkenden Zentrifugalkraft und der stattfindender Trennung bildet sich ein Flüssigkeitsring aus, dessen äußerer Durchmesser dem Innendurchmesser der Zentrifugentrommel (2) entspricht und dessen Innendurchmesser durch die Stellung des Wehrs (8) der Austragsöffnung (5) für die leichten Stoffe (Flüssigkeit) gegeben ist und in der Zeichnungsfigur der gestrichelten Linie (9) entspricht.In the drawing figure, a known full-shell screw centrifuge (1) in countercurrent design with a leading screw conveyor (4) is shown. The liquid-solid mixture to be separated is introduced through the feed device (14) along the axis of rotation into the screw centrifuge (1) and passes through the openings (7) into the separation space formed by the centrifuge drum (2) and the screw drum (13). Due to the centrifugal force acting on the introduced mixture and the separation taking place, a liquid ring is formed, the outer diameter of which corresponds to the inner diameter of the centrifuge drum (2) and the inner diameter of which is determined by the position of the weir (8) of the discharge opening (5) for the light substances ( Liquid) is given and corresponds to the broken line (9) in the drawing.
Bei der erfindungsgemäßen schlagartigen Drehzahländerung durch Abbremsen der Zentrifugentrommel (2) und/oder der Förderschnecke (4), der der Flüssigkeitsring infolge einer Trägheit zunächst nicht folgt, "schraubt" sich der Flüssigkeitsring in-folge seiner nun relativ zur Förderschnecke (4) schnelleren Drehzahl entgegen der Förderrichtung (in der Zeichnungsfigur nach rechts) in Richtung zu den Austragsöffnungen (5) für die leichten Stoffe hin (in der Zeichnungsfigur nach links).In the case of the sudden change in speed according to the invention by braking the centrifuge drum (2) and / or the screw conveyor (4), which the liquid ring does not initially follow due to inertia, the liquid ring "screws" as a result of its now faster speed relative to the screw conveyor (4) against the conveying direction (to the right in the figure) towards the discharge openings (5) for the light fabrics (to the left in the figure).
Da wegen der begrenzten Kapazität der Austragsöffnungen (5) für die auszutragenden leichten Stoffe (11) nicht sofort alle Flüssigkeit ausgetragen werden kann, ergibt sich zunächst (bis der größte Teil der Flüssigkeit ausgetragen ist) ein neuer Flüssigkeitsring mit der Innenfläche (12), der sich gegen die linke Stirnwand der Zentrifugentrommel (2) drängt und sich somit von den Austragsöffnungen (6) für die schweren Stoffe (10) zurückzieht.Since, due to the limited capacity of the discharge openings (5) for the light substances (11) to be discharged, not all of the liquid can be discharged immediately, a new liquid ring with the inner surface (12) results first (until most of the liquid has been discharged) pushes against the left end wall of the centrifuge drum (2) and thus withdraws from the discharge openings (6) for the heavy substances (10).
Durch die erfindungsgemäße Maßnahme wird somit erfolgreich verhindert, daß beim Zusammenbrechen des Flüssigkeitsrings auch Flüssigkeit an der Austragsöffnung (6) für die schweren Stoffe (10) mit ausgetragen wird.The measure according to the invention thus successfully prevents liquid from also being discharged at the discharge opening (6) for the heavy substances (10) when the liquid ring collapses.
Die Erfindung ist nicht nur auf das in der Zeichnungsfigur dargestellte Ausführungsbeispiel einer Gegenstromschneckenzentrifuge beschränkt, sondern auch auf andere Schneckenzentrifugen, so z. B. Gleichstromschneckenzentrifugen, Siebschneckenzentrifugen etc. anwendbar, deren Förderschnecken mit voreilender oder nacheilender Drehzahl angetrieben sind.The invention is not only limited to the embodiment of a countercurrent screw centrifuge shown in the drawing figure, but also to other screw centrifuges, e.g. B. DC screw centrifuges, screen screw centrifuges etc. applicable, the conveyor screws of which are driven at a leading or lagging speed.
Claims (3)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE4321964 | 1993-07-01 | ||
| DE4321964A DE4321964A1 (en) | 1993-07-01 | 1993-07-01 | Process for operating screw centrifuges |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| EP0631820A2 true EP0631820A2 (en) | 1995-01-04 |
| EP0631820A3 EP0631820A3 (en) | 1995-05-31 |
| EP0631820B1 EP0631820B1 (en) | 1999-10-27 |
Family
ID=6491739
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP94107900A Expired - Lifetime EP0631820B1 (en) | 1993-07-01 | 1994-05-21 | Process for operating a screw centrifuge |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US5474515A (en) |
| EP (1) | EP0631820B1 (en) |
| DE (2) | DE4321964A1 (en) |
| DK (1) | DK0631820T3 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4439938A1 (en) | 1994-11-09 | 1996-05-15 | Kloeckner Humboldt Deutz Ag | Process for operating screw centrifuges |
| DE19952804C2 (en) * | 1999-11-02 | 2003-07-03 | Westfalia Separator Ind Gmbh | Solid bowl screw centrifuge for processing a centrifugal material that tends to foam |
| DE10220757B4 (en) * | 2002-05-08 | 2004-06-24 | Westfalia Separator Ag | Centrifuge, especially separator |
| DE10223802B4 (en) * | 2002-05-29 | 2005-06-09 | Westfalia Separator Ag | Solid bowl centrifuge |
| US6972411B2 (en) * | 2002-10-03 | 2005-12-06 | Schick Technologies, Inc. | Method of event detection for intraoral image sensor |
| KR100920449B1 (en) | 2007-10-04 | 2009-10-08 | 이강찬 | Centrifugal separator |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2551788A1 (en) * | 1975-11-18 | 1977-06-02 | Flottweg Werk Bruckmayer | FULLY-SLEEVED SCREW CENTRIFUGE WITH DIFFERENTIAL SPEED-VARIABLE COUPLING BETWEEN SHEATH PART AND SCREW PART |
| US4978331A (en) * | 1989-07-11 | 1990-12-18 | Alfa-Laval Ab | Method and apparatus for cleaning in place of a decanter centrifuge |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1632325B1 (en) * | 1967-06-02 | 1970-05-27 | Turbo Separator Ag | Continuously working, screenless screw centrifuge |
| US3494542A (en) * | 1968-05-27 | 1970-02-10 | Pennwalt Corp | Centrifuging process and apparatus |
| DE2063063C3 (en) * | 1970-12-22 | 1975-10-16 | Amberger Kaolinwerke Gmbh, 8452 Hirschau | Process for separating the solids from a suspension, as well as for promoting the internal transport and discharge of the thickened sludge in solid bowl centrifuges, as well as centrifuges serving to carry out the process |
| DE2125522A1 (en) * | 1971-05-22 | 1972-12-07 | Mse Holdings Ltd | Centrifugal separator - with by-pass chamber esp for machine tool coolant with swarf |
| SU582001A1 (en) * | 1976-06-23 | 1977-11-30 | Всесоюзный научно-исследовательский и проектный институт галургии | Method of automatic control of suspension separating process in screw-type settling centrifuge |
| DE2835108A1 (en) * | 1978-08-10 | 1980-02-14 | Lacher Jorge Halder | Releasing compacted sugar crystals from centrifuge screen - using sudden applied braking force to screen (BR 26.9.78) |
| DE3044797A1 (en) * | 1980-11-28 | 1982-07-01 | Fluormatic GmbH, 7407 Rottenburg | Removing solids from liq. using two centrifuges - superimposed in common casing and operated independently |
| US5176616A (en) * | 1989-06-29 | 1993-01-05 | Kloeckner-Humboldt-Deutz Aktiengesellschaft | Method and apparatus for the after-treatment of the thick material in the thick material discharge region of a solid bowl worm centrifuge |
| DE4104752A1 (en) * | 1990-02-15 | 1991-08-22 | Krauss Maffei Ag | Dislodging deepening cake residue from centrifugal filter - by flooding surface before abrupt rotary speed change |
-
1993
- 1993-07-01 DE DE4321964A patent/DE4321964A1/en not_active Withdrawn
-
1994
- 1994-05-21 DE DE59408853T patent/DE59408853D1/en not_active Expired - Fee Related
- 1994-05-21 DK DK94107900T patent/DK0631820T3/en active
- 1994-05-21 EP EP94107900A patent/EP0631820B1/en not_active Expired - Lifetime
- 1994-06-28 US US08/267,561 patent/US5474515A/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2551788A1 (en) * | 1975-11-18 | 1977-06-02 | Flottweg Werk Bruckmayer | FULLY-SLEEVED SCREW CENTRIFUGE WITH DIFFERENTIAL SPEED-VARIABLE COUPLING BETWEEN SHEATH PART AND SCREW PART |
| US4978331A (en) * | 1989-07-11 | 1990-12-18 | Alfa-Laval Ab | Method and apparatus for cleaning in place of a decanter centrifuge |
Also Published As
| Publication number | Publication date |
|---|---|
| DE4321964A1 (en) | 1995-01-12 |
| EP0631820B1 (en) | 1999-10-27 |
| DK0631820T3 (en) | 2000-01-17 |
| DE59408853D1 (en) | 1999-12-02 |
| EP0631820A3 (en) | 1995-05-31 |
| US5474515A (en) | 1995-12-12 |
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