EP0167653B1 - Soupape pour couvercle de décanteuse centrifuge - Google Patents

Soupape pour couvercle de décanteuse centrifuge Download PDF

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Publication number
EP0167653B1
EP0167653B1 EP19840108192 EP84108192A EP0167653B1 EP 0167653 B1 EP0167653 B1 EP 0167653B1 EP 19840108192 EP19840108192 EP 19840108192 EP 84108192 A EP84108192 A EP 84108192A EP 0167653 B1 EP0167653 B1 EP 0167653B1
Authority
EP
European Patent Office
Prior art keywords
drum
ring
lid
overflow
liquid
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.)
Expired
Application number
EP19840108192
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German (de)
English (en)
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EP0167653A1 (fr
Inventor
Volkmar Hentschel
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BMA Braunschweigische Maschinenbauanstalt AG
Original Assignee
BMA Braunschweigische Maschinenbauanstalt AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by BMA Braunschweigische Maschinenbauanstalt AG filed Critical BMA Braunschweigische Maschinenbauanstalt AG
Priority to EP19840108192 priority Critical patent/EP0167653B1/fr
Priority to DE8484108192T priority patent/DE3465892D1/de
Publication of EP0167653A1 publication Critical patent/EP0167653A1/fr
Application granted granted Critical
Publication of EP0167653B1 publication Critical patent/EP0167653B1/fr
Expired legal-status Critical Current

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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
    • B04B1/02—Centrifuges with rotary bowls provided with solid jackets for separating predominantly liquid mixtures with or without solid particles without inserted separating walls
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
    • B04B—CENTRIFUGES
    • B04B11/00—Feeding, charging, or discharging bowls
    • B04B11/04—Periodical feeding or discharging; Control arrangements therefor

Definitions

  • the invention relates to an overflow separation centrifuge for separating suspensions, in particular sludge, in solid and liquid, in which a rotatingly driven centrifugal drum with a horizontally extending axis of rotation is arranged at all sides from the housing in a stationary housing, the centrifugal drum being essentially cylindrical , has a closed, flat drum bottom and a flat circular cover, which extends radially from the drum casing to a circular overflow edge lying between the axis of rotation and the drum casing, and a filling device for supplying suspension through the opening of the cover delimited by the overflow edge extends into the vicinity of the drum base and a clearing device for discharging the separated solid is passed through (see US Pat. No. 1,896,806).
  • the suspension In centrifuges of the type mentioned at the beginning, the suspension is separated into solid and liquid under the influence of the gravitational field, which produces a drum speed of about 500 to 800 rpm.
  • the solid sediments or accumulates on the drum jacket because it is specifically heavier than the liquid.
  • the liquid flows out of the centrifugal drum at the overflow edge. As soon as the solid layer is thick enough, the supply of suspension is interrupted and the solid is discharged from the clearing device.
  • the drum As a rotating body, the drum is subject to the gyroscopic laws and is exposed to certain imbalances during the filling and overflow of separated liquid and during the deposition of solid matter, which are compensated for by the fact that the drum axis of rotation performs certain movements in space, which are made possible by appropriate storage. If one assumes that these movements of the axis of rotation of the drum are particularly large in the vicinity of the cover, are very small in the area of the center and are somewhat larger again near the bottom of the drum, then one has an explanation for the formation of the liquid rings. Since these phenomena are specific properties of the centrifuges described, they cannot be avoided; the improvement of the achievable dry content of the solid and the solid Material yield must therefore be done in a different way.
  • the invention is therefore based on the object to provide a centrifuge of the type mentioned for a suitable for draining unwanted liquid, controlled actuated valve system that works reliably both at the operating speed of the drum and in the event of imbalance-induced vibrations of the drum, which also against heavy dirt accumulation is insensitive, generates no imbalance through its actuation and does not adversely affect the gyro behavior of the drum.
  • the leaf springs have no difficulty. precisely balance the ring with the U-section and the hose inside, as well as the support plates attached to the ring with the rubber plates, so that there is gyroscopic symmetry.
  • the ring which is U-shaped in cross section, needs only a very small axial stroke in order to open the liquid outlet openings by lifting the rubber plates from the outer surface of the cover. Therefore, this lifting movement does not cause any disturbance in the gyro behavior of the drum. It helps that the total weight of the moving parts is very low compared to the drum and the drum content.
  • the elastically stretchable hose in the ring as a pneumatic working member acting against the leaf springs. Since this hose is received in the ring with the U-cross section, it only has one degree of freedom for expansion when pressure is applied, because the ring is rigid. A simple type of axial stroke is thus realized, which takes place under a gaseous pressure medium. Tightly tolerated sliding surfaces, as are required with the usual working members consisting of pistons and cylinders, are no longer necessary. It is also avoided that sliding surfaces between the piston and the cylinder have to be moved at high pressures under the influences of the centrifugal forces or imbalance-induced vibrations of the drum, which is known to impair both the operational reliability and the service life. Thus, the liquid outlet openings can be reliably opened and closed in all operating states of the drum, without the need for expensive devices, such as pneumatic working members.
  • control can be carried out by control valves outside the centrifuge.
  • a particular advantage according to claim 3 is that the stretchable hose is designed as a commercially available pressurizable seal, so it does not have to be bought or manufactured as an expensive custom-made product.
  • the opening stroke can be adjusted as desired and can be kept as small as possible.
  • the hexagon head cap screws also provide a simple and reliable centering of the rubber plates to the liquid outlet openings.
  • overflow edge according to claim 6 is formed by one end of a sleeve which is inserted into the central lid opening and extends in the axial direction outwards over the ring and the heads of the screws which limit the opening stroke, then a particularly reliable shielding is Movable devices guaranteed against contamination.
  • FIG. 1 shows an overflow separation centrifuge (1) in which a centrifugal drum (3) is accommodated in a housing (2).
  • the centrifugal drum (3) has a hollow cylindrical drum casing (4) which is closed at one end by means of a closed drum base (5) and is provided with an annular drum cover (6) at the other end.
  • a connecting sleeve (7) is attached, which is used for connection to a drive shaft, not shown.
  • the drum (3) is set in rotation about 500 to 800 rpm by the drive shaft around the axis of the hollow cylinder.
  • the connecting sleeve (7) or alternatively the drive shaft are elastically mounted so that the centrifugal drum (3) can perform compensatory gyroscopic movements due to unbalance during rotation.
  • the elastically damped mounting can be arranged on the connecting sleeve (7) or on the drive shaft, not shown.
  • Housing (2) and drum cover (6) have a circular hole concentric with the drum axis of rotation, an opening (8) through which a filling device, not shown, for feeding the suspension to be separated extends into the vicinity of the drum base (5), and a removal device, also not shown, for discharging the separated solid projects into the interior of the drum.
  • the centrifuge (1) suspension is fed near the drum base (5) while the drum (3) rotates.
  • the suspension is carried along by the contact with the drum wall, accelerated, and begins to flow in the longitudinal direction of the drum (3) under the influence of gravity due to the horizontal course of the drum axis of rotation as well as under the influence of the rotational centrifugal acceleration.
  • the centrifugal acceleration has a separating effect, so that the specifically heavier fraction of the suspension, the solid, adheres to the drum wall, i.e. the H. attached to the inside of the drum casing (4).
  • the specifically lighter liquid accumulates radially inside the solid and becomes' less or less solids-free with increasing solids exposure to centrifugal acceleration, while the solids become increasingly drier.
  • the summit of this curve which is also the point of greatest proximity to the axis of rotation of the centrifugal drum (3) and the location of the greatest thickness of the solid layer, lies on the length of the drum shell (4) at a distance from the drum base (5) and near the center of the Drum length. From this summit, the curve drops both in the direction of the drum base (5) and in the direction of the drum cover (6) in the direction of the drum casing (4) and undercuts the level of the overflow edge (9). Above these areas of the curve which forms the solid surface, which are below the level of the overflow edge (9), areas arise which are filled with liquid and which cannot be removed by further suspension addition. If the separation work were removed at this stage, the degree of dryness of the solid would be due to the Liquid components impaired.
  • liquid outlet openings (11) are arranged in the drum cover (6) at equal distances from one another and from the drum axis of rotation. Their distance from the drum casing is selected so that the outer areas of the liquid outlet openings (11) protrude slightly from the inside just below the surface of the solid layer, or the curve that defines its course. This ensures that any liquid film, no matter how thin, can flow off on the surface of the solid. Before, however, a sufficiently high solid layer has not yet accumulated, there must be no drainage possibility through the liquid outlet openings, because liquid which has not been sufficiently freed of solids and enriched with suspension would exit.
  • rubber plates (12) rest on the outside of the drum cover (6), which are each centered with the associated liquid outlet opening (11).
  • the rubber sheets (12) can be square, e.g. B. be square and are substantially larger than the liquid outlet openings (11). This ensures a good seal.
  • the rubber plates (12) are fastened to support plates (14) by means of screws (13).
  • the support plates (14) are fastened to the outer leg (15) of a circular ring (16) which has a U cross section and faces the outside of the drum cover (6) with the open side of the U cross section.
  • Leaf springs (19) are screwed to the blocks (18) and project radially inwards and rest on the back (20) of the U-cross section of the ring (16).
  • the leaf springs (19) transmit a pressure force on the rubber plates (12) via the ring (16) and the support plates (14) and ensure the secure sealing of the liquid outlet openings (11).
  • An elastically stretchable hose (21) is arranged in the interior of the ring, the cross section of which is identical to the inner cross section of the ring (16).
  • the hose (21) is slightly shorter than the circumference of the ring (16) and closed at both ends.
  • a pressure hose (23) is connected to one of these closed ends via fittings (22), FIG. 4, which pass through the outer U-leg (15) of the ring (16).
  • This runs radially and through the edge (17) by means of at least one further fitting (22) which is designed as an angled fitting and merges into a pipeline (24) which runs along the outside of the drum shell (4) to the drum base (5), is angled again in the direction of the drum axis of rotation and ends in a rotary transmitter, not shown, which is connected to a controllable compressed air source which is arranged outside the housing (2).
  • a commercially available seal that can be subjected to compressed air is advantageously used as the hose (21), which has a profiled side (25) which faces the drum cover (6).
  • the U-legs of the ring (16) protrude the side (25) of the hose (21).
  • a flat, flat ring (26) is attached to the outside of the drum cover (6) and lies with lateral play between the U-legs. If compressed air is fed into the hose (21) towards the end of the separation process, the hose (21) within the ring (16) can only expand elastically in the direction of the open end of the U cross section; the side (25) lies against the flat ring (26) and the ring (16) together with the support plates (14) and the rubber plates (12) are moved away from the drum cover (6) in the drum axis direction against the action of the leaf springs (19) . This clears the liquid outlet openings (11) and the liquid flows below the level of the overflow edge (9).
  • the rubber plates (12) When the hose (21) is relieved of pressure again, the rubber plates (12) again lie under the action of the leaf springs (19) against the surface of the drum cover (6) and close the liquid outlet openings (11) tightly. Since the hose (21) can be pressurized with several bars, the leaf springs (19) can also be designed to be sufficiently strong, so that there is a good sealing pressure.
  • This type of centering has the particular advantage that the ring (16) is reliably held in its position on the one hand, but on the other hand during its axial lifting movements when opening and closing the liquid outlet openings (11) only point-like or linear sliding contact with the heads (30 ) Has. It can therefore not build up strong frictional forces even under the strongest unbalanced vibration loads of the ring (16) could hinder the function. If the centering set screws (29) or at least the heads (30) are made of high quality material or hardened steel, wear is countered. You can also readjust when closing. If the centrifugal behavior of the centrifugal drum (3) should not change during the working strokes of the ring (16), then this stroke must be limited so that no large masses are moved axially. Due to the design of the ring, the use of the hose (21) and the low cost of materials for support plates (14) and rubber plates (12), a low weight is achieved, so that no large masses are moved during the working stroke.
  • tabs (32) are fastened to the radially outer U-leg (15) of the ring (16) (FIG. 3) and have bores (33) running parallel to the axis of rotation of the drum.
  • the tabs (32) are distributed at regular intervals over the circumference of the ring (16).
  • Hexagon head cap screws (34) with their shafts are accommodated with play in the bores (33).
  • the threaded ends of the hexagon head cap screws (34) are screwed into the drum cover (6); the desired screw-in depth, which limits the working stroke of the ring (16), is fixed by lock nuts (35).
  • the ring (16) can only be removed from the drum cover as far as the tabs (32) can slide on the hexagon socket head cap screws (34) as far as the stop on the screw head.
  • the hexagon head cap screws (34) and the tabs cause the ring (16) to rotate when the centrifugal drum (3) rotates.
  • a sleeve (36) is inserted into the opening (8) of the drum cover (6).
  • this sleeve (36) forms the overflow edge (9), at the other end it extends in the axial direction to such an extent that the ring (16) and the leaf springs are protected from liquid and dirt, which are thrown off radially at this end .
  • the design of the liquid outlet openings (11) to be opened and closed in the manner of a valve, as described for the drum cover (6), can also be provided on the drum base (5) in order to drain off the liquid accumulations that occur there.
  • the liquid outlet openings (11) When arranged on the drum base (5), only the liquid outlet openings (11) have to be arranged at a greater radial distance from the axis of rotation of the drum because the liquid pockets reach deeper into the drum casing (5).
  • the described design makes it possible to remove residual liquid and thus increase the degree of dryness of the solid. It may also be refilled after the residual liquid has been drained off, so that a thicker solid layer is obtained. Thus, the capacity of the centrifuge 1 is increased. The material and cost involved in achieving this result is low, especially since comparative primitive devices are used, the manufacture of which does not require high precision.
  • An annular sliding seal (37) between the sleeve (36) and the inner leg of the ring (16) serves to further protect against contamination.

Landscapes

  • Centrifugal Separators (AREA)

Claims (6)

1. Séparateur centrifuge à débordement (1) pour séparer des suspensions, notamment de la boue, en matière solide et en liquide, dans lequel un panier centrifuge (3) entraîné en rotation est disposé dans un carter fixe (2), avec un axe de rotation horizontal éloigné de tous côtés du carter, le panier centrifuge (3) est de forme sensiblement cylindrique, comporte un fond de panier (5) plan fermé ainsi qu'un couvercle (6) annulaire plan, qui s'étend radialement de l'enveloppe (4) du panier jusqu'à une arête de débordement (9) annulaire située entre l'axe de rotation et l'enveloppe du panier, un dispositif de remplissage saille à travers l'ouverture du couvercle délimitée par l'arête de débordement (9) pour amener les suspensions jusqu'à proximité du fond du panier, de même qu'y saille un dispositif d'évacuation pour évacuer la matière solide séparée, caractérisé en ce qu'au moins le couvercle (6) du panier comporte plusieurs orifices de sortie de liquide (11) répartis à intervalles réguliers sur un cercle s'étendant entre l'arête de débordement (9) et l'enveloppe (4) du panier, en ce qu'une bague (16) est maintenue, coaxialement à l'axe de rotation du panier, sur le côté extérieur du couvercle (6) dans la zone comprise entre les orifices de sortie de liquide (11) et l'arête de débordement (9), laquelle bague a une section transversale en U ouverte vers le couvercle (6) et est munie, sur l'aile radialement extérieure (15) de la section en U, de plaques supports (14) sur lesquelles sont fixées des plaques de caoutchouc (12), lesquelles sont respectivement centrées sur un orifice de sortie de liquide (11) et appuient de façon étanche sur le côté extérieur du couvercle de panier (6), en obturant l'orifice de sortie de liquide correspondant (11), par des zones situées à l'extérieur de l'orifice de sortie de liquide correspondant sous l'influence de plusieurs ressorts à lame (19) répartis régulièrement sur la périphérie du panier. s'étendant radialement par rapport à l'axe de rotation du panier et appuyant de l'extérieur sur le dos du U (20) par les extrémités radialement intérieures, et en ce que dans la bague (16) de section en U est disposé un tuyau souple (21) de section transversale adaptée à la section transversale du U, élastiquement dilatable, lequel tuyau peut être relié par commande à une source d'air ou de gaz comprimé au moyen d'une canalisation souple ou dure (23, 24) et d'un dispositif transmettant la rotation, grâce à quoi les plaques de caoutchouc (12) peuvent être soulevées du couvercle de panier (6) contre l'action des ressorts à lame (19) et les orifices de sortie de liquide (11) sont ouverts pour évacuer du liquide résiduel enrichi au voisinage du couvercle.
2. Séparateur centrifuge à débordement selon la revendication 1, caractérisé en ce qu'on fixe sur le côté extérieur du couvercle de panier (6) une bague plate (26) de section transversale rectangulaire, disposée avec un jeu latéral entre les ailes du U de la bague (16), en tant que butée de pression pour le tuyau souple (21).
3. Séparateur centrifuge à débordement selon la revendication 1 et/ou 2, caractérisé en ce que le tuyau souple (21) est réalisé sous forme d'un joint d'étanchéité du commerce pouvant être soumis à la pression.
4. Séparateur centrifuge à débordement selon l'une ou plusieurs des revendications 1 à 3, caractérisé en ce qu'on fixe sur le côté extérieur du couvercle de panier (6) plusieurs blocs régulièrement répartis (27) qui reçoivent des vis de réglage de centrage (29), lesquelles s'étendent radialement par rapport à l'axe de rotation du panier et présentent leurs têtes plates (30) face, avec très peu de jeu, à la branche radialement extérieure (15) de la bague (16).
5. Séparateur centrifuge à débordement selon l'une ou plusieurs des revendications 1 à 4, caractérisé en ce que plusieurs pattes (32) alésées parallèlement à l'axe du panier sont fixées sur l'aile radialement extérieure (15) du U de la bague (16), que les fûts de vis partiellement filetés (34) à tête à six pans sont guidés dans les alésages (33) des pattes (32), lesquelles vis sont vissées dans le couvercle de panier (6) pour limiter la course d'ouverture de la bague (16), et que les pattes (32) sont réparties à intervalles réguliers.
6. Séparateur centrifuge à débordement selon l'une ou plusieurs des revendications 1 à 5, caractérisé en ce que l'arête de débordement (9) est prévue sur l'arête intérieure d'une douille (36) introduite dans le couvercle de panier (6), laquelle douille s'étend parallèlement à l'axe du panier vers l'extérieur jusqu'au delà de la bague (16), et qu'un joint d'étanchéité glissant (37) est disposé entre la périphérie extérieure de la douille (36) de forme cylindrique et la branche radialement intérieure du U de la bague (16).
EP19840108192 1984-07-12 1984-07-12 Soupape pour couvercle de décanteuse centrifuge Expired EP0167653B1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP19840108192 EP0167653B1 (fr) 1984-07-12 1984-07-12 Soupape pour couvercle de décanteuse centrifuge
DE8484108192T DE3465892D1 (en) 1984-07-12 1984-07-12 Valve for the lid of a decanter centrifuge

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP19840108192 EP0167653B1 (fr) 1984-07-12 1984-07-12 Soupape pour couvercle de décanteuse centrifuge

Publications (2)

Publication Number Publication Date
EP0167653A1 EP0167653A1 (fr) 1986-01-15
EP0167653B1 true EP0167653B1 (fr) 1987-09-09

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ID=8192050

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19840108192 Expired EP0167653B1 (fr) 1984-07-12 1984-07-12 Soupape pour couvercle de décanteuse centrifuge

Country Status (2)

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EP (1) EP0167653B1 (fr)
DE (1) DE3465892D1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI106873B (fi) * 1998-05-26 2001-04-30 Outokumpu Oy Menetelmä uuttolaitteiston tiivistämiseksi

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1896806A (en) * 1930-01-10 1933-02-07 Albert T Otto & Sons Centrifugal machine
US2748788A (en) * 1951-04-28 1956-06-05 Maytag Co Centrifugally operated valve
US3377019A (en) * 1965-09-15 1968-04-09 Baker Perkins Inc Methods and apparatus for maintaining a liquid head in a centrifuge
GB2077632B (en) * 1980-06-13 1984-08-30 Chan Kean Cheong Separation of mixtures of solids and liquids

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Publication number Publication date
DE3465892D1 (en) 1987-10-15
EP0167653A1 (fr) 1986-01-15

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