EP0161995A1 - Verfahren zur Behandlung von Giessereisänden zum Wiedererlangen von Chromit und Vorrichtung dazu - Google Patents

Verfahren zur Behandlung von Giessereisänden zum Wiedererlangen von Chromit und Vorrichtung dazu Download PDF

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Publication number
EP0161995A1
EP0161995A1 EP85420051A EP85420051A EP0161995A1 EP 0161995 A1 EP0161995 A1 EP 0161995A1 EP 85420051 A EP85420051 A EP 85420051A EP 85420051 A EP85420051 A EP 85420051A EP 0161995 A1 EP0161995 A1 EP 0161995A1
Authority
EP
European Patent Office
Prior art keywords
mixture
plate
chromite
silica
support
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
Application number
EP85420051A
Other languages
English (en)
French (fr)
Other versions
EP0161995B1 (de
Inventor
Gabriel Battie
Yves Bonnel
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.)
Centre Stephanois de Recherches Mecaniques Hydromecanique et Frottement SA
Original Assignee
Centre Stephanois de Recherches Mecaniques Hydromecanique et Frottement SA
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 Centre Stephanois de Recherches Mecaniques Hydromecanique et Frottement SA filed Critical Centre Stephanois de Recherches Mecaniques Hydromecanique et Frottement SA
Publication of EP0161995A1 publication Critical patent/EP0161995A1/de
Application granted granted Critical
Publication of EP0161995B1 publication Critical patent/EP0161995B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03B—SEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS
    • B03B4/00—Separating by pneumatic tables or by pneumatic jigs
    • B03B4/02—Separating by pneumatic tables or by pneumatic jigs using swinging or shaking tables
    • 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 subject of the invention relates, in particular, to the technical sectors of foundry, the manufacture of parts by casting of metal in molds, the recovery of materials or components of molds and in particular chromite and silica, and also the separation in general of the components of a mixture which have different densities.
  • the object of the process for treating foundry sands according to the invention is to separate and recover, after casting, the silica, the chromite and the metallic shot, so as to be able to reuse the sand and the chromite which can be thus implement in repetitive cycles subject to replacing losses due to various causes.
  • This sand treatment process according to the invention is characterized in that, after the molding of the parts and their extraction from the molds which have been broken, the mixture resulting from the release is recovered in a first cycle, this mixture being stored in a silo ; the mixture is conveyed from the storage silo to an intermediate silo, for example and preferably by a pneumatic blower; the mixture contained in the silo is passed, for example by gravity and with a flow rate controlled by a regulating valve, to a sieve size sorting device to separate grains or particles into several batches of different sizes.
  • Each batch of grains is conveyed to a separating table operating according to a method and means making it possible to separate the chromite from the silica; it is recovered in containers or by means of transporters or otherwise, on the one hand the chromite and on the other hand the silica.
  • the treatment process is characterized in that, after the shot peening of the parts extracted from the molds, the mixture resulting from the peening is recovered, this mixture being stored in a silo; the mixture is conveyed from the storage silo to an intermediate silo, for example and preferably using a pneumatic blower; the mixture contained in the intermediate silo is passed, for example by gravity and with a flow rate controlled by a regulating valve, through a magnetic drum sorter which separates the particles or metallic grains which are recovered and discharged, for example at by means of a conveyor belt, the mixture without particles or metallic grains is passed, for example by gravity and with a flow rate regulated by a valve, from the magnetic sorter to a fluidized bed sorter device, allowing grains to be separated or particles in several categories of different densities; concerning categories taken in order of increasing densities: fines and dust are collected in a general dust collector; the pure silica is collected by evacuating it, for example by means of a conveyor belt; the
  • a process of separation of the components (grains, particles for example) of a mixture, which have different densities is implemented, this process of separation being characterized in that the mixture is subjected to combined and simultaneous effects according to which, on the one hand, the components are fluidized by the effect of air or a gaseous fluid or pressure through a plane or plate ensuring microsuperficial diffusion , while, on the other hand, vibrations, of amplitude, frequency, intensity and adjustable directional effect are applied to the plate or support, combined with an adjustable torque effect, which ensure the separate evacuation out of of the plan or plate of each component of the mixture.
  • the mixture is brought with a suitable flow rate onto an inclined support or plate of the porous type; air or other gaseous fluid under pressure is sent in an adjustable manner as regards the flow rate and the speed, in a closed volume, under the plate or support which ensures regular microsuperficial diffusion and the fluidization of the components, the most dense remain in contact with the plate or support, while the less dense are suspended in the air or diffused gaseous fluid; is applied to the support or plate, in its plane, vibrations of adjustable frequency and amplitude and these vibrations are combined with the effects of at least one mass adjustable in intensity and position relative to the plate or support, said mass being linked to the upper part of said tray or support by communicating to the latter a tilting effect tending to raise the lower part of the tray, said tray is mounted on its frame or other support assembly by means of elastic supports giving the plate spatial freedom in all directions; an effect is thus obtained at all points on the plate
  • the mixture to be sorted passes by gravity for example in the example shown, on a particle classifier (3) separating the grains or particles of the mixture in several batches of different grain sizes, for exam- pl e five different batches (+ 800f + 400 ⁇ + 250 ⁇ + 140Y - 140 t)
  • a special separating table (4) Figures 3, 4 and 5 .
  • these separating tables (4) could be produced in any way and according to any known method, for example using grids or sieves having suitably calibrated openings, or else according to the characteristic arrangements which have been the subject of French Patents N ° 73.29274, 74.28510, 78.20580.
  • FIG. 1 also illustrates this installation in a schematic manner, and we see the storage silo (7) which receives the mixture resulting from shot peening and from which said mixture is conveyed to an intermediate silo (8) by any known means and using for example a pneumatic blower.
  • the flow rate of the mixture to be sorted is controlled by a regulating valve to pass by gravity effect, from the silo (8) to a magnetic drum sorter (9) of the type known per se, which eliminates the magnetic particles contained in the mixture, particles which are removed for example by means of a conveyor belt (10).
  • the mixture without particles or metallic grains is then directed to a sorting device (11) with a fluidized bed.
  • a process is used for preparing the components (chromite and silica) which have different densities.
  • the mixture is subjected to combined and simultaneous effects according to which, on the one hand, the components are fluidized by the effect of air or a gaseous fluid under pressure through an inclined plane or plate ( 16) of the separating table (4), said plate being shaped to ensure, in a known manner, a microsuperficial diffusion.
  • One of the transverse ends of the plate (16), on the lowest side, is controlled by a vibrating device (17), while the other end is controlled by a set of adjustable masses (18).
  • the masses (18) are mounted projecting from the active part of the plate, being supported by arms (18a) mounted in the extension and beyond the lateral sides of said plate.
  • the plate is liable to be subjected to vibrations of adjustable amplitude, frequency, intensity and directional effect combined with an adjustable torque effect, to ensure separate evacuation.
  • plate, of each component, chromite and silica, of the mixture are fluidized by the effect of air or a gaseous fluid under pressure through an inclined plane or plate ( 16) of the separating table (4), said
  • the diffuser plate (16) is mounted by any known and appropriate means, in an inclined and adjustable manner on the support frame (19) of the table (4) while being secured, at each of its upper and lower transverse ends, in particular to blocks or elements (20) with elastic deformation capacity.
  • Under the plate (16) is formed a volume closed by a flexible membrane (22).
  • An air generator (23) or other means opens into the bottom of the sealed volume (22), to send air under pressure inside said volume, to fluidize the components, chromite and silica, placed on the tray.
  • FIGS. 3, 4 and 5 Illustrated in FIGS. 3, 4 and 5, an embodiment of the separating table corresponding to the operating principle shown in FIG. 2.
  • the mixture is brought with a suitable flow rate on the inclined plate (16) of the porous type.
  • chromite constitutes the dense products
  • silica constitutes the light or less dense products.
  • the vibrator device (17) subjects, in its plane, the plate (16) to adjustable frequency and amplitude vibrations. These vibrations are combined with the effects of adjustable masses (18), in intensity, and in position relative to the plate (16).
  • the masses can be adjusted in height on a vertical element (18b) of support arm (18a) and / or moved in length relative to said arms.
  • the set of masses (18) being linked to the upper part of the plate (16), communicates to the latter, in combination with the amplitudes of the vibrator (17), a tilting effect which tends to cause the elevation of the lower part of the tray.
  • the elastic supports (20) give the tray a spatial freedom in all directions, the flexible membrane (22) ensuring air tightness between the tray (16) and the separating table support housing (4).
  • the plate (16) due to its conformation, fluidizes the products to be separated, such so that the dense products (chromite) remain in contact with the bottom of the diffuser plate (16) while the lighter products (silica) remain in suspension.
  • the vibratory movements subjected to the plate (16), in combination with the masses (18) tend to cause the rise of the dense components which overflow in the upper part of the plate, the less dense components in suspension, not subjected to the vibratory movements, descend by gravity to come overflowing at the other end, in the lower part of the plate (16) ( Figure 2).
  • the longitudinal tilting torque created by the adjustable masses is also capable of advancing the heavy products in contact with the table, by ballistic phenomenon. Indeed, under a very strong acceleration following very substantially the resultant R, the grain of and falling back into chromite must take off from the plate / at the moment when said plate has made its return movement and so on

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Molds, Cores, And Manufacturing Methods Thereof (AREA)
  • Combined Means For Separation Of Solids (AREA)
  • Mold Materials And Core Materials (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Processing Of Solid Wastes (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)
  • Glanulating (AREA)
EP85420051A 1984-03-21 1985-03-19 Verfahren zur Behandlung von Giessereisänden zum Wiedererlangen von Chromit und Vorrichtung dazu Expired - Lifetime EP0161995B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8404696A FR2561554B1 (fr) 1984-03-21 1984-03-21 Procede de traitement des sables de fonderie pour, notamment, recuperer la chromite, ainsi que l'installation et les moyens de mise en oeuvre du procede
FR8404696 1984-03-21

Publications (2)

Publication Number Publication Date
EP0161995A1 true EP0161995A1 (de) 1985-11-21
EP0161995B1 EP0161995B1 (de) 1991-06-12

Family

ID=9302473

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85420051A Expired - Lifetime EP0161995B1 (de) 1984-03-21 1985-03-19 Verfahren zur Behandlung von Giessereisänden zum Wiedererlangen von Chromit und Vorrichtung dazu

Country Status (10)

Country Link
US (1) US4671867A (de)
EP (1) EP0161995B1 (de)
KR (1) KR850007011A (de)
AT (1) ATE64332T1 (de)
DE (2) DE3583184D1 (de)
ES (2) ES8801592A1 (de)
FR (1) FR2561554B1 (de)
IL (1) IL74588A (de)
RO (1) RO93730B (de)
YU (1) YU45085A (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0504747A3 (en) * 1991-03-22 1993-09-08 Alb. Klein Gmbh & Co. Kg Method and device for sifting sand or similar free-flowing material
CN106424542A (zh) * 2016-08-29 2017-02-22 山西永益铸管股份有限公司 铸管废砂回收装置

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3719288A1 (de) * 1987-06-10 1988-12-22 Foerder & Anlagentechnik Gmbh Verfahren und anordnung zum trennen von schuettguetern unterschiedlichen spezifischen gewichtes
US5071541A (en) * 1988-09-30 1991-12-10 The Boeing Company Method and apparatus for sorting a mixture of particles
US4943368A (en) * 1988-11-15 1990-07-24 Pittsburgh Mineral & Environmental Technology, Inc. Nonmetallic abrasive blasting material recovery process including an electrostatic separation step
CH689202A5 (de) * 1993-12-10 1998-12-15 Fischer Georg Giessereianlagen Verfahren zum Regenerieren von Giesserei-Altsand mit Anteilen von schwach magnetischen Stoffen.
US6277128B1 (en) 1998-07-11 2001-08-21 J. Scott Muldner Skin abrasion treatment device
US6631808B2 (en) 2001-08-07 2003-10-14 Particle And Coating Technologies, Inc. Air classifier system for the separation of particles
US6691765B2 (en) 2001-08-07 2004-02-17 Noram Technology, Ltd. Products for the manufacture of molds and cores used in metal casting and a method for their manufacture and recycle from crushed rock
KR20040009290A (ko) * 2002-07-23 2004-01-31 아이앤아이스틸 주식회사 주물사의 분리시스템
US8764350B2 (en) * 2008-06-05 2014-07-01 Alstom Technology Ltd Conveyor for transporting powder, and a method for conveying powder
CN109641263B (zh) * 2016-08-22 2021-04-06 艾莫考国际公司 用于从铸造废料回收砂和活性粘土的工艺过程
DE102020004891A1 (de) * 2020-08-11 2022-02-17 Allgaier Werke Gmbh System und Verfahren zur gravimetrischen Sortierung eines Stoffgemischs

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR763365A (fr) * 1933-01-21 1934-04-30 Manche Atel Chantiers Procédé et appareil pour la séparation à sec de produits de densités différentes
DE2252259A1 (de) * 1972-10-25 1974-05-09 Halbergerhuette Gmbh Einrichtung zum rueckgewinnen von giesserei-formgrundstoff
DE2448333A1 (de) * 1974-10-10 1976-04-22 Escher Wyss Gmbh Formsandreiniger
FR2425279A1 (fr) * 1978-05-11 1979-12-07 Sosson Guy Procede et dispositif pour trier et classer des particules solides de matieres diverses de densites relativement voisines

Family Cites Families (12)

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Publication number Priority date Publication date Assignee Title
US2348344A (en) * 1941-11-25 1944-05-09 Birtley Co Ltd Process of separating intermixed divided materials
US2452362A (en) * 1944-12-19 1948-10-26 Link Belt Co Apparatus for treating flowable solids
US2635753A (en) * 1948-06-01 1953-04-21 Lyle G Mclean Air stratifier
US2698086A (en) * 1952-01-10 1954-12-28 Vogel Walter Arrangement for removing dust from granular material
FR1477593A (fr) * 1966-03-02 1967-04-21 Siderurgie Fse Inst Rech Procédé de classement pneumatique d'un produit pulvérulent
US3764078A (en) * 1970-12-01 1973-10-09 Applic Prod Ind Apparatus for regenerating foundry sand
US4144088A (en) * 1977-01-19 1979-03-13 Kenzler Engineering Company, Inc. Process of reclaiming used foundry sand
US4354641A (en) * 1979-02-26 1982-10-19 Weatherly Foundry & Manufacturing Co. Apparatus for removing no-bake coatings from foundry sand and classifying the reclaimed sand
US4449566A (en) * 1979-04-09 1984-05-22 Ford Motor Company Foundry sand reclamation
SU933178A1 (ru) * 1980-10-09 1982-06-07 Научно-Исследовательский И Проектно-Конструкторский Институт Стройматериалов Им.Дадашева Способ регенерации отработанных формовочных песчано-глинистых смесей
JPS5897462A (ja) * 1981-12-07 1983-06-09 Mazda Motor Corp 鋳型バツクアツプ用シヨツトの分離回収装置
JPH109542A (ja) * 1996-06-24 1998-01-16 Babcock Hitachi Kk ごみ焼却方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR763365A (fr) * 1933-01-21 1934-04-30 Manche Atel Chantiers Procédé et appareil pour la séparation à sec de produits de densités différentes
DE2252259A1 (de) * 1972-10-25 1974-05-09 Halbergerhuette Gmbh Einrichtung zum rueckgewinnen von giesserei-formgrundstoff
DE2448333A1 (de) * 1974-10-10 1976-04-22 Escher Wyss Gmbh Formsandreiniger
FR2425279A1 (fr) * 1978-05-11 1979-12-07 Sosson Guy Procede et dispositif pour trier et classer des particules solides de matieres diverses de densites relativement voisines

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0504747A3 (en) * 1991-03-22 1993-09-08 Alb. Klein Gmbh & Co. Kg Method and device for sifting sand or similar free-flowing material
CN106424542A (zh) * 2016-08-29 2017-02-22 山西永益铸管股份有限公司 铸管废砂回收装置

Also Published As

Publication number Publication date
ES541470A0 (es) 1988-02-16
YU45085A (en) 1988-10-31
ES557767A0 (es) 1988-10-01
FR2561554B1 (fr) 1986-08-14
KR850007011A (ko) 1985-10-30
ES8900269A1 (es) 1988-10-01
EP0161995B1 (de) 1991-06-12
US4671867A (en) 1987-06-09
IL74588A (en) 1987-10-20
ES8801592A1 (es) 1988-02-16
DE3583184D1 (de) 1991-07-18
RO93730A (ro) 1988-06-30
FR2561554A1 (fr) 1985-09-27
DE161995T1 (de) 1987-03-19
RO93730B (ro) 1988-07-02
ATE64332T1 (de) 1991-06-15
IL74588A0 (en) 1985-06-30

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