EP0512236B1 - Procédé de récupération mécanique de sable de fonderie décoché - Google Patents

Procédé de récupération mécanique de sable de fonderie décoché Download PDF

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Publication number
EP0512236B1
EP0512236B1 EP92105216A EP92105216A EP0512236B1 EP 0512236 B1 EP0512236 B1 EP 0512236B1 EP 92105216 A EP92105216 A EP 92105216A EP 92105216 A EP92105216 A EP 92105216A EP 0512236 B1 EP0512236 B1 EP 0512236B1
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EP
European Patent Office
Prior art keywords
cleaning
foundry sand
sand
process according
container
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 - Lifetime
Application number
EP92105216A
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German (de)
English (en)
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EP0512236A1 (fr
Inventor
Volker Dipl.-Ing. Godderidge
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.)
Kgt Giessereitechnik GmbH
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Kgt Giessereitechnik GmbH
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Publication of EP0512236A1 publication Critical patent/EP0512236A1/fr
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C5/00—Machines or devices specially designed for dressing or handling the mould material so far as specially adapted for that purpose
    • B22C5/18—Plants for preparing mould materials
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S241/00—Solid material comminution or disintegration
    • Y10S241/10—Foundry sand treatment

Definitions

  • the invention relates to a method for the mechanical cleaning of foundry sand by means of thermo-mechanical regeneration, the foundry sand being blown pneumatically against a deflection hood.
  • EP-A1 0 343 272 A batch-wise treatment of used sands occurring in foundries is proposed in EP-A1 0 343 272.
  • the sand in a container is treated by friction elements that rotate about an axis and are moved by the batch.
  • the object of the invention is to clean foundry sand thermo-mechanically so that it has a constant quality that comes close to that of new sand.
  • this object is achieved in that the foundry sand is subjected to batches of mechanical-pneumatic cleaning in a separate apparatus before and / or after thermal regeneration.
  • the foundry sand is sucked into the blower tube above a sheet which is arranged at a distance from its bottom and provided with openings (preferably nozzle screws), with an air stream emerging from a blower nozzle at a distance from its vertical blow tube.
  • the old sand accelerated by the air flow passes through the blow pipe to a deflection hood attached above the blow pipe and is flung against its inner surface.
  • the parallel connection of at least two such cleaning containers ensures quasi-continuous operation of a foundry sand cleaning system.
  • the cleaning effect of the foundry sand can be easily regulated by varying the air delivery pressure, changing the distance at the end of the blowpipe and on the deflection hood, as well as adjusting the angle of impact of the foundry sand on the deflection hood and the duration of the cleaning process.
  • the deflection hood attached to the upper part of the container can be fixed by simple mechanical means at different distances from the end of the blowpipe and possibly be pivoted through certain angles. This makes it possible to achieve greater cleaning effects at the beginning of the cleaning process and to achieve a gentler treatment of the grains towards the end of the cycle.
  • hot air can advantageously be used to convey and fluidize the old sand.
  • the air is advantageously heated using the waste heat from the thermal regeneration. At temperatures of the hot air above 350 ° C, it is possible to dry the inorganic contaminants safely and quickly.
  • the mechanical pre-cleaning of bentonite-bound used sand is made more difficult by the residual moisture that is necessarily present.
  • the still active bentonite absorbs a lot of water and acts like a "lubricant". This reduces the cleaning effect caused by Kornan-Korn friction.
  • the hot conveying and fluidizing air flowing around the old sand on all sides dries and embrittles the bentonite layer adhering to it very quickly, making it easier to remove mechanically.
  • the valve on the container is opened and the now preheated and pre-cleaned old sand is fed to a thermal regeneration stage, such as a fluidized bed oven.
  • a thermal regeneration stage such as a fluidized bed oven.
  • the old sand is then cleaned of the organic binders adhering to it and the "dead burning" of the bentonites which are also still adhering.
  • a similar pneumatic-mechanical cleaning can follow the thermal regeneration stage. It proves to be advantageous to provide a heat exchanger in the interior of the container above the plate provided with holes, which cools the old sand falling from the deflection hood. Of the thermally regenerated used sand reaches the container at a temperature of approx. 650 ° C. The fireclay shells of the quartz grains are softer in this state than after cooling to approx. 50 ° C. This results in a gentler cleaning of the fireclay shells than at comparatively low temperatures, so that less grain destruction can be expected. Due to the cooling to be carried out in the container, the bentonites become brittle and thermal stresses arise, which enables easier separation. The invention is to be explained below using two exemplary embodiments.
  • the foundry sand arrives from a pre-container 1 into the cleaning container 2.
  • An air flow is generated by a fan 6, which flows through the heat exchanger 7 and is heated therein by the heat of the fluidized bed furnace 10.
  • the air heats up in the heat exchanger 7 to values of 400-500 ° C (at least 350 ° C).
  • the now hot air passes through the air duct 3 into the cleaning container 2 and conveys the old sand through the blow pipe 4.
  • the old sand accelerated with the air flow impinges against the deflection hood 5 and impurities adhering to it, particularly inorganic binders, burst off in the process. Due to the very hot medium air, which flows around the old sand on all sides, the bentonite dries very quickly. This embrittles and is therefore easier to remove from the old sand.
  • the old sand falls onto a perforated plate 19 which is attached above the bottom of the cleaning container.
  • nozzle screws preferably cross-drilled hollow screws, through which the air flows into the cleaning container 2 and fluidizes the foundry sand.
  • the foundry sand on the bottom plate 19 of the cleaning container in turn reaches the blow pipe 4 and is sucked into it by means of the air flow.
  • the used sand runs through this cycle until a certain drying and cleaning effect or a certain preheating temperature is reached, in order then to be removed from the cleaning container 2 via the line 17.
  • a shut-off device not shown, which opens or closes the line 17. From the line 17, the pre-cleaned old sand reaches an intermediate container 8 and is fed via a vibration conveyor 9 to a fluidized bed furnace 10, in which the old sand is subjected to thermal regeneration.
  • the residues and valuable substances removed in a cyclone have a high concentration of bentonite and whole carbon, which are immediately returned to the green sand processing.
  • the proportion of undersize quartz in the dust increases, the dust separated in the cyclone is fed to the fluidized bed furnace 10 for combustion of the organic constituents and inerting of the residues.
  • FIG. 2 shows the cleaning tank 2, which is basically of the same design, following a thermal regeneration stage, in the form of a fluidized bed oven 10.
  • the hot used sand passes through an intermediate container 11 into the cleaning container 2, in which there is a heat exchanger 12 for cooling the hot used sand above the plate 19 provided with holes.
  • the pneumatic-mechanical post-cleaning works like the corresponding pre-cleaning.
  • cold air is conveyed into the cleaning container 2 by a fan 14 through the air duct 3. This, in cooperation with the heat exchanger 12, ensures rapid cooling of the old sand, which was hot up to that point.
  • the favorable control options and the possibility of predetermining the cleaning time ensure that a lower proportion of grain destruction occurs.
  • the foundry sand that has been cleaned in this way can at most be returned to the mold or core production, such as new sand.
  • the combination of several operations in one part of the plant ensures economic operation of a foundry sand cleaning plant.
  • the foundry sand can be dried, preheated, pre-cleaned in a pre-cleaning stage and simultaneously cooled, post-cleaned and sifted during the pneumatic-mechanical post-cleaning. This eliminates the need for additional facilities such as Intermediate conveyors that are required for other types of systems.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Molds, Cores, And Manufacturing Methods Thereof (AREA)
  • Mold Materials And Core Materials (AREA)
  • Casting Devices For Molds (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)

Claims (11)

  1. Procédé de nettoyage mécanique de sable de fonderie souillé par régénération thermomécanique, le sable souillé étant soufflé par voie pneumatique d'une cuve (2) contre une hotte de renvoi (5) à l'aide d'un courant d'air passant par un tube de soufflage (4), caractérisé en ce que le sable souillé acheminé dans la cuve avant et/ou après un traitement thermique est fluidisé sur une tôle perforée (19) à l'aide d'air froid ou chaud en fonction de l'humidité et/ou de la température et en ce qu'il est soufflé de manière répétée, à l'intérieur d'une charge, contre la hotte de renvoi (5) jusqu'à atteindre un nettoyage suffisant, après quoi le sable souillé est évacué de la cuve (2).
  2. Procédé selon la revendication 1, caractérisé en ce qu'on règle la distance entre l'extrémité du tube de soufflage et la hotte de renvoi.
  3. Procédé selon les revendications 1 et 2, caractérisé en ce qu'on règle l'angle d'impact du sable souillé sur la hotte de renvoi.
  4. Procédé selon les revendications 1 à 3, caractérisé en ce qu'on règle la pression d'acheminement pneumatique.
  5. Procédé selon les revendications 1 à 4, caractérisé en ce que les substances résiduaires et les substances valables de moindre masse que le sable souillé sont évacuées par une ouverture prévue dans la zone supérieure de la cuve et recyclées.
  6. Procédé selon les revendications 1 à 5, caractérisé en ce qu'au début du courant d'air, on effectue un réglage tel que ce courant s'écoule seulement par des ouvertures d'une tôle de fond et fluidise le sable souillé en le préséchant et en le réchauffant ou en le refroidissant de la sorte, sans qu'il ne soit aspiré par le tube de soufflage.
  7. Procédé selon les revendications 1 à 6, caractérisé en ce que le sable souillé, après la régénération thermique, tombe, lors de son post-nettoyage dans la cuve, sur un échangeur de chaleur et est refroidi au cours de son séjour dans la cuve.
  8. Procédé selon les revendications 1 à 7, caractérisé en ce que, lors du pré-nettoyage mécanico-pneumatique, le sable souillé est soufflé contre la hotte de renvoi par de l'air chaud.
  9. Procédé selon les revendications 1 à 5 et 7, caractérisé en ce que le sable souillé est soufflé contre la hotte de renvoi par de l'air chaud provenant de la régénération thermique à une température d'au moins 350°C.
  10. Procédé selon les revendications 1 à 5 et 8 et 9, caractérisé en ce que, lors du pré-nettoyage mécanique, depuis son début jusqu'à un point où la fraction de déclassés inférieurs de quartz dans la poussière a atteint une certaine valeur, la fraction de bentonite et de carbone total, qui est retirée par l'ouverture ménagée dans la zone supérieure et un cyclone monté en aval, est acheminée immédiatement à la zone de préparation de sable vert.
  11. Procédé selon les revendications 1 à 5, et 8 et 9, caractérisé en ce que, après avoir atteint le point où la fraction de déclassés inférieurs de quartz dans la poussière augmente, la poussière séparée est acheminée au four à lit fluidisé pour brûler les composants organiques et rendre inertes les matières résiduaires.
EP92105216A 1991-04-10 1992-03-26 Procédé de récupération mécanique de sable de fonderie décoché Expired - Lifetime EP0512236B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4111726 1991-04-10
DE4111726A DE4111726C2 (de) 1991-04-10 1991-04-10 Verfahren zur mechanischen Reinigung von Gießereialtsand

Publications (2)

Publication Number Publication Date
EP0512236A1 EP0512236A1 (fr) 1992-11-11
EP0512236B1 true EP0512236B1 (fr) 1995-12-06

Family

ID=6429302

Family Applications (1)

Application Number Title Priority Date Filing Date
EP92105216A Expired - Lifetime EP0512236B1 (fr) 1991-04-10 1992-03-26 Procédé de récupération mécanique de sable de fonderie décoché

Country Status (6)

Country Link
US (1) US5291935A (fr)
EP (1) EP0512236B1 (fr)
AT (1) ATE131091T1 (fr)
DE (2) DE4111726C2 (fr)
DK (1) DK0512236T3 (fr)
ZA (1) ZA922356B (fr)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2696367B1 (fr) * 1992-10-07 1994-12-23 Fm Ind Procédé et installation de régénération de sables de fonderies hétérogènes.
DE4237838A1 (de) * 1992-11-10 1994-05-11 Badische Maschf Gmbh Verfahren und Vorrichtung zum Regenerieren von Gießereialtsand
DE4322947B4 (de) * 1992-11-27 2006-02-02 Förder- und Anlagentechnik GmbH Anordnung zur Verbesserung der Verarbeitungsgeigenschaften von Sanden
DE4316610A1 (de) * 1993-05-18 1994-11-24 Gut Gieserei Umwelt Technik Gm Öko-Sandregenerierung mech./pneum. im Chargenbetrieb
DE4434115C1 (de) * 1994-09-23 1995-11-23 Kgt Giessereitechnik Gmbh Verfahren zur pneumatisch-mechanischen Reinigung von in Gießereien anfallenden Altsanden
JP3355325B2 (ja) * 2000-05-18 2002-12-09 旭有機材工業株式会社 原料鋳物砂又はシェルモールド用レジンコーテッドサンドの温度調節ユニット及びこれを用いた温度調節装置
DE10346062B4 (de) * 2003-10-04 2006-03-23 Daimlerchrysler Ag Verfahren zur Herstellung eines Gussteils
CA2916810A1 (fr) * 2015-01-12 2016-07-12 Russell Wynn Driver Raffinage de sable en vue de retirer les impuretes
JP6687400B2 (ja) * 2016-01-26 2020-04-22 リグナイト株式会社 鋳型製造装置
JP6687399B2 (ja) * 2016-01-26 2020-04-22 株式会社大阪シェル 鋳物砂の加熱装置
IT201800004618A1 (it) * 2018-04-17 2019-10-17 Procedimento per la rigenerazione di sabbie di fonderia.
CN108705030B (zh) * 2018-07-04 2024-03-29 柳晶（溧阳）环保科技有限公司 一种铸造废砂处理设备

Family Cites Families (19)

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Publication number Priority date Publication date Assignee Title
US2478461A (en) * 1946-03-16 1949-08-09 Nichols Eng & Res Corp Apparatus and method for treating foundry sand
US3230635A (en) * 1962-07-09 1966-01-25 Dietert Co Harry W Dryer and heater for granular material
DE1806842A1 (de) * 1968-11-04 1970-05-27 Wilhelm Schwiese Verfahren und Vorrichtung,um Giesserei-Altsande zu regenerieren
US3825190A (en) * 1973-02-14 1974-07-23 Nat Eng Co Apparatus for treating granular material
SE7505070L (sv) * 1974-05-02 1975-11-03 Simpson Ag Maschinen Reningsanleggning.
FR2278424A1 (fr) * 1974-06-10 1976-02-13 Sapic Procede et appareil pour le nettoyage mecanique et pneumatique et le depoussierage d'une substance granuleuse et/ou pulverulente
US4144088A (en) * 1977-01-19 1979-03-13 Kenzler Engineering Company, Inc. Process of reclaiming used foundry sand
CH631643A5 (de) * 1978-04-14 1982-08-31 Fischer Ag Georg Verfahren zur regenerierung von giesserei-altsand sowie einrichtung zur durchfuehrung des verfahrens und erzeugnis des verfahrens.
DE3110578A1 (de) * 1981-03-18 1982-09-30 Hermann 2105 Seevetal Jacob Vorrichtung zur reinigung von giessereialtsand
DE3561928D1 (en) * 1984-01-11 1988-04-28 Gsr Sandregenerierungsgesellsc Process and machine for regenerating used foundry sand
DE3400648A1 (de) * 1984-01-11 1985-07-18 Delta Engineering Beratung und Vermittlung Gesellschaft mbH, Irdning Vorrichtung und verfahren zur regeneration von giesserei-schuttsand
EP0149876A1 (fr) * 1984-01-20 1985-07-31 Wheelabrator-Frye Inc. Procédé et appareil pour la récupération de sable de fonderie
US4636168A (en) * 1984-08-10 1987-01-13 Institute Of Gas Technology Apparatus for thermal and pneumatic treatment of granular solids
DE3636479A1 (de) * 1986-10-27 1988-05-05 Foerder & Anlagentechnik Gmbh Verfahren und anordnung zur thermo-mechanischen regenerierung von schuettguetern, insbesondere von giesserei-altsand
ATE79062T1 (de) * 1988-05-26 1992-08-15 Pohl Giessereitechnik Verfahren und vorrichtung zum regenieren von giessereialtsanden.
DE3825361A1 (de) * 1988-07-26 1990-02-08 Hermann Jacob Verfahren und anlage zur regenerierung von giessereialtsandgemischen
DE3929178A1 (de) * 1989-09-02 1991-03-21 Balcke Duerr Ag Wirbelschichtreaktor und zugehoeriges betriebsverfahren
CH680498A5 (fr) * 1989-11-28 1992-09-15 Fischer Ag Georg
CH682641A5 (de) * 1990-11-23 1993-10-29 Fischer Ag Georg Verfahren zum Trennen der Bentonit- und Kohlenstoffträgerpartikel von dem bei der Altsandregenerierung auf mechanischem Wege gewonnenen Staub.

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Metal Handbook 9th Edition, Vol. 15, Casting, 1988, Metals Park, S. 352-354 *

Also Published As

Publication number Publication date
DE4111726A1 (de) 1992-10-15
ATE131091T1 (de) 1995-12-15
EP0512236A1 (fr) 1992-11-11
DE4111726C2 (de) 1994-02-24
DK0512236T3 (da) 1996-01-22
ZA922356B (en) 1992-11-25
DE59204541D1 (de) 1996-01-18
US5291935A (en) 1994-03-08

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