EP0162834B1 - Magnetic separator - Google Patents

Magnetic separator Download PDF

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Publication number
EP0162834B1
EP0162834B1 EP19850890117 EP85890117A EP0162834B1 EP 0162834 B1 EP0162834 B1 EP 0162834B1 EP 19850890117 EP19850890117 EP 19850890117 EP 85890117 A EP85890117 A EP 85890117A EP 0162834 B1 EP0162834 B1 EP 0162834B1
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EP
European Patent Office
Prior art keywords
magnetic
force
coils
magnetic field
magnetic separator
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EP19850890117
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German (de)
French (fr)
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EP0162834A2 (en
EP0162834A3 (en
Inventor
Harald Dipl.-Ing. Fillunger
Stephan Dr. Gründorfer
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Andritz Hydro GmbH Austria
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Andritz Hydro GmbH Austria
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    • 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
    • B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C1/00—Magnetic separation
    • B03C1/02—Magnetic separation acting directly on the substance being separated
    • B03C1/035—Open gradient magnetic separators, i.e. separators in which the gap is unobstructed, characterised by the configuration of the gap

Definitions

  • the invention relates to a magnetic separator, preferably for separating materials with small differences in magnetic susceptibility, consisting of excitation coils to create a magnetic field in the separating volume in which the particles to be separated are exposed to a counterforce and a component of the magnetic force.
  • the magnetic separators used industrially today are generally well suited to separating materials with ferromagnetic or strongly paramagnetic properties from other materials with diamagnetic or weakly paramagnetic properties. A separation of materials with only slight differences in their paramagnetic properties is only possible in some magnetic separators that are suitable for laboratory purposes.
  • gravity is used as counterforce, which is why it is required that the cutting force density f should be constant over the cutting volume.
  • the magnetic field that meets these conditions is referred to in this document as an isodynamic magnetic field.
  • Such a magnetic field is approximated by a specially shaped magnetic pole contour of an electromagnet with an iron yoke. If you want a different size as a counterforce, e.g. B. use the centrifugal force, the separation force density f must have the same spatial distribution as the counterforce.
  • the level of magnetic induction is essentially limited to the saturation induction of the iron yoke.
  • the greatest possible density of the cutting force is defined.
  • the maximum magnetic induction must be increased if the geometry remains the same, or the geometric dimension must be reduced if the maximum induction remains the same.
  • a method for separating magnetic from non-magnetic particles is known.
  • a magnet that can be used for magnetic separation is described, which, due to its arrangement, generates a mainly radial and a weak axial magnetic field in the separation volume.
  • the particles to be separated move perpendicular to the magnetic field and to the magnetic field gradient under the influence of gravity.
  • the magnetic fields and magnetic field gradients arising in this magnetic separator are therefore not matched to the counterforces created by gravity.
  • the object of the invention is to provide a magnetic separator which avoids the disadvantages of the above-mentioned magnetic fields and generates a magnetic field in which, for a certain volume sensitivity, the generated separating force is adapted to a corresponding counterforce, without being limited by the saturation induction of an iron yoke.
  • the magnetic separator according to the invention is characterized in that an equilibrium of forces is generated between the magnetic force and the opposing counterforce on the particles located in the separating volume, the magnetic field being largely induced by the shape and position of the excitation coils.
  • the magnetic field is induced by rotationally symmetrical coils, which are arranged symmetrically to the cutting volume and flow through in opposite directions with respect to the plane of symmetry and comprise the cutting volume and the Radius of the center of the vaginal volume is smaller than the largest radius of the excitation coils, but larger than the smallest radius of the excitation coils.
  • the magnetic field is induced by elongated coils, the long sides of the coil being arranged symmetrically to a plane of symmetry and comprising the sheath volume arranged symmetrically to the plane of symmetry.
  • excitation coils are made of normally conductive material. This version is sufficient for certain vaginal problems. It is an economically viable solution.
  • the excitation coils are made from superconductors. Weakly magnetic materials can only be separated using magnetic fields that can be generated from superconductors.
  • one or more iron cores or iron yokes are provided to increase the magnetic induction or to reduce the number of ampere turns.
  • one or more iron yokes or a normally conducting or a superconducting surface are provided for shielding the magnetic field.
  • a rotationally symmetrical excitation coil arrangement is shown in the figure, 1 denoting the axis of rotation and 2 denoting the plane of symmetry.
  • the excitation coils 3 and 5, which are arranged above the plane of symmetry 2, are, for. B. flowed through in a positive sense, the excitation coils 4 and 6, which are arranged below the plane of symmetry 2, are accordingly flowed through in a negative sense.
  • the counterforce is the centrifugal force which acts in the annular channel-shaped partition volume 7 on the particles moving at the transport speed.
  • the magnetic separating force density exerts a different force on the different material particles due to the different volume sensitivities of the materials to be separated. This magnetic force competes with the counterforce, which is approximately the same for all particles. For particulates of greater than Ks Volumssuszeptibiltician outweighs the magnetic force, while for particulates smaller than Ks Volumssuszeptibiltician outweighs the counterforce.
  • the counterforce is a superimposition of the drag forces in the carrier fluid with the force of gravity.
  • the volume of the sheath generally lies between the excitation coils. Assuming constant current density across the cross sections of the excitation coils, the desired constancy of the cutting force density over the cutting volume or the desired adaptation to the spatially variable counterforce can be achieved with a coil pair with a non-rectangular cross section or with several coil pairs with a rectangular cross section. When using pairs of coils with different current densities in the individual coil cross-sections of any shape, the desired constancy of the cutting force density over the cutting volume or the desired adaptation to the spatially variable counterforce can be achieved.

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  • Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
  • Soft Magnetic Materials (AREA)

Description

Die Erfindung betrifft einen Magnetscheider, vorzugsweise zur Trennung von Materialien mit geringen Unterschieden in der magnetischen Suszeptibilität, bestehend aus Erregerspulen zur Schaffung eines Magnetfeldes im Scheidevolumen, in dem die zu trennenden Teilchen einer Gegenkraft und einer Komponente der Magnetkraft ausgesetzt werden.The invention relates to a magnetic separator, preferably for separating materials with small differences in magnetic susceptibility, consisting of excitation coils to create a magnetic field in the separating volume in which the particles to be separated are exposed to a counterforce and a component of the magnetic force.

Die heute industriell verwendeten Magnetscheider sind im allgemeinen gut geeignet, Materialien mit ferromagnetischen oder stark paramagnetischen Eigenschaften von anderen Materialien mit diamagnetischen oder schwach paramagnetischen Eigenschaften zu trennen. Eine Trennung von Materialien mit nur geringen Unterschieden in ihren paramagnetischen Eigenschaften gelingt nur in einigen für Laboratoriumszwecke geeigneten Magnetscheidern.The magnetic separators used industrially today are generally well suited to separating materials with ferromagnetic or strongly paramagnetic properties from other materials with diamagnetic or weakly paramagnetic properties. A separation of materials with only slight differences in their paramagnetic properties is only possible in some magnetic separators that are suitable for laboratory purposes.

Aus der US-PS Nr. 2.056.426 über ein derartiges Gerät ist bekannt, daß zur weitgehenden Trennung von Materialien mit geringen Unterschieden in ihren paramagnetischen Eigenschaften ein Magnetfeld notwendig ist, bei den die Kräfte auf Teilchen mit einer bestimmten Volumssuszeptibilität Ks unabhängig sind vom Ort im betrachtetem Scheidevolumen. Dazu muß ein Gleichgewicht herrschen zwischen der magnetischen Kraft und einer entgegengesetzt gerichteten Gegenkraft auf die Teilchen. Die magnetische Kraft auf ein Teilchen mit der Volumssuszeptibilität K und dem Teilchenvolumen V ist:

Figure imgb0001
From US Pat. No. 2,056,426 on such a device it is known that a magnetic field is necessary for the extensive separation of materials with small differences in their paramagnetic properties, in which the forces on particles with a certain volume sensitivity Ks are independent of the location in the considered vaginal volume. To do this, there must be a balance between the magnetic force and an opposing counterforce on the particles. The magnetic force on a particle with the volume susceptibility K and the particle volume V is:
Figure imgb0001

Die Feldgröße f = /B/ - grad H ist eine Beschreibung des Magnetfeldes, sie hat die Dimension einer Kraftdichte (N/m3) und wird als Scheidekraftdichte bezeichnet. Bei dem in der genannten US-PS beschriebenen Magnetscheider wird die Schwerkraft als Gegenkraft benützt, weshalb gefordert wird, daß die Scheidekraftdichte f über das Scheidevolumen konstant sein soll. Das Magnetfeld, das diese Bedingungen erfüllt, wird in dieser Druckschrift als isodynamisches Magnetfeld bezeichnet. Ein solches Magnetfeld wird durch speziell geformte Magnetpolkontur eines Elektromagneten mit Eisenjoch angenähert. Will man als Gegenkraft eine andere Größe wie z. B. die Fliehkraft heranziehen, so muß die Scheidekraftdichte f die gleiche räumliche Verteilung wie die Gegenkraft haben.The field size f = / B / - degree H is a description of the magnetic field, it has the dimension of a force density (N / m 3 ) and is called the separation force density. In the magnetic separator described in the aforementioned US patent, gravity is used as counterforce, which is why it is required that the cutting force density f should be constant over the cutting volume. The magnetic field that meets these conditions is referred to in this document as an isodynamic magnetic field. Such a magnetic field is approximated by a specially shaped magnetic pole contour of an electromagnet with an iron yoke. If you want a different size as a counterforce, e.g. B. use the centrifugal force, the separation force density f must have the same spatial distribution as the counterforce.

Bei Magnetscheidern mit Magnetflußführung durch ein Eisenjoch ist zur Formung des notwendigen Magnetfeldes eine entsprechende Kontur des Eisenjoches notwendig. Bei solchen Magnetscheidern ist die Höhe der magnetischen Induktion im wesentlichen auf die Sättigungsinduktion des Eisenjoches beschränkt. Im Verein mit einer gewünschten Geometrie des Volumens, in dem die Materialien getrennt werden sollen, ist somit die größtmögliche Scheidekraftdichte definiert.In magnetic separators with magnetic flux guidance through an iron yoke, a corresponding contour of the iron yoke is necessary to form the necessary magnetic field. In such magnetic separators, the level of magnetic induction is essentially limited to the saturation induction of the iron yoke. In combination with a desired geometry of the volume in which the materials are to be separated, the greatest possible density of the cutting force is defined.

Sind größere Scheidekraftdichten notwendig, so muß bei gleichbleibender Geometrie die maximale magnetische Induktion erhöht werden oder bei gleichbleibender maximaler Induktion die geometrische Abmessung verringert werden.If greater cutting force densities are necessary, the maximum magnetic induction must be increased if the geometry remains the same, or the geometric dimension must be reduced if the maximum induction remains the same.

Eine Vergrößerung der geometrischen Abmessungen zum Zwecke eines größeren Durchsatzes und/oder der Scheidung größerer Kornklassen bedingt eine Erhöhung der maximalen Induktion, wenn die Scheidekraftdichte unverändert bleiben soll. Das hat zur Folge, daß zur Formung des Magnetfeldes nicht mehr ausschließlich das Eisenjoch verwendet werden kann. Die Form des Magnetfeldes wird mit zunehmender Stärke der magnetischen Induktion mehr und mehr von der Lage und der Form der Erregerspulen bestimmt. Die Erhöhung der Induktion erfordert hohe Amperewindungszahlen.An increase in the geometric dimensions for the purpose of a larger throughput and / or the separation of larger grain classes requires an increase in the maximum induction if the density of the separation force is to remain unchanged. As a result, the iron yoke can no longer be used exclusively to form the magnetic field. The shape of the magnetic field is increasingly determined by the position and shape of the excitation coils as the strength of the magnetic induction increases. Increasing induction requires high ampere turns.

Aus der FR-A-2 467 020 ist ein Verfahren zur Trennung magnetischen von unmagnetischen Teilchen bekannt. Bei diesem Verfahren wird ein zur Magnetscheidung verwendbarer Magnet beschrieben, der durch seine Anordnung ein hauptsächlich radiales und ein schwaches axiales Magnetfeld im Scheidevolumen erzeugt. Die zu trennenden Teilchen bewegen sich dabei senkrecht zum Magnetfeld und zum Magnetfeldgradienten unter dem Einfluß der Schwerkraft. Die in diesem Magnetscheider entstehenden Magnetfelder und Magnetfeldgradienten sind daher nicht auf die von der Schwerkraft gebildeten Gegenkräfte abgestimmt.From FR-A-2 467 020 a method for separating magnetic from non-magnetic particles is known. In this method, a magnet that can be used for magnetic separation is described, which, due to its arrangement, generates a mainly radial and a weak axial magnetic field in the separation volume. The particles to be separated move perpendicular to the magnetic field and to the magnetic field gradient under the influence of gravity. The magnetic fields and magnetic field gradients arising in this magnetic separator are therefore not matched to the counterforces created by gravity.

Aufgabe der Erfindung ist es, einen Magnetscheider zu schaffen, der die Nachteile der obengenannten Magnetfelder vermeidet und ein Magnetfeld erzeugt, bei dem für eine bestimmte Volumssuszeptibilität die hervorgerufene Scheidekraft einer entsprechenden Gegenkraft angepaßt ist, ohne dabei durch die Sättigungsinduktion eines Eisenjoches beschränkt zu sein.The object of the invention is to provide a magnetic separator which avoids the disadvantages of the above-mentioned magnetic fields and generates a magnetic field in which, for a certain volume sensitivity, the generated separating force is adapted to a corresponding counterforce, without being limited by the saturation induction of an iron yoke.

Der erfindungsgemäße Magnetscheider ist dadurch gekennzeichnet, daß ein Kräftegleichgewicht zwischen der magnetischen Kraft und der entgegengesetzt gerichteten Gegenkraft auf die im Scheidevolumen befindlichen Teilchen erzeugt wird, wobei das Magnetfeld im überwiegenden Ausmaß durch die Form und Lage der Erregerspulen induziert ist.The magnetic separator according to the invention is characterized in that an equilibrium of forces is generated between the magnetic force and the opposing counterforce on the particles located in the separating volume, the magnetic field being largely induced by the shape and position of the excitation coils.

Mit der Erfindung ist es erstmals möglich, die der Erfindung gestellte Aufgabe optimal einer Lösung zuzuführen. Eine kontinuierliche Scheidemöglichkeit für unterschiedlich paramagnetische Materialien ist dadurch gegeben. Darüberhinaus wird eine hohe Trennschärfe bei industriell benötigtem großem Durchsatz erzielt.With the invention, it is possible for the first time to optimally solve the object of the invention. This enables continuous cutting of different paramagnetic materials. In addition, a high degree of selectivity is achieved with a high throughput required industrially.

Gemäß einer besonderen Ausgestaltung der Erfindung ist das Magnetfeld durch rotationssymmetrische Spulen induziert, die symmetrisch zum Scheidevolumen angeordnet und in Bezug auf die Symmetrieebene gegensinnig stromdurchflossen sind und das Scheidevolumen umfassen und der Radius des Zentrums des Scheidevolumens kleiner ist, als der größte Radius der Erregerspulen, jedoch größer als der kleinste Radius der Erregerspulen. Dadurch ist eine einfache Lösung des Problems gegeben, die Geometrie der Magnetspulen festzulegen.According to a special embodiment of the invention, the magnetic field is induced by rotationally symmetrical coils, which are arranged symmetrically to the cutting volume and flow through in opposite directions with respect to the plane of symmetry and comprise the cutting volume and the Radius of the center of the vaginal volume is smaller than the largest radius of the excitation coils, but larger than the smallest radius of the excitation coils. This provides a simple solution to the problem of determining the geometry of the magnet coils.

Nach einer Weiterbildung der Erfindung ist das Magnetfeld durch langgestreckte Spulen induziert, wobei die Spulenlängsseiten symmetrisch zu einer Symmetrieebene angeordnet sind und das symmetrisch zur Symmetrieebene angeordnete Scheidevolumen umfassen. Diese Merkmale beziehen sich auf eine Scheidekanalanordnung in nicht rotationssymmetrischer Geometrie. Für diese Bedingungen liefert die Spulenanordnung optimale Konstanz der Scheidekraftdichte.According to a further development of the invention, the magnetic field is induced by elongated coils, the long sides of the coil being arranged symmetrically to a plane of symmetry and comprising the sheath volume arranged symmetrically to the plane of symmetry. These features relate to a separating channel arrangement with a non-rotationally symmetrical geometry. For these conditions, the coil arrangement provides optimum consistency in the density of the cutting force.

Entsprechend einer weiteren Ausgestaltung der Erfindung sind Erregerspulen aus normalleitendem Material hergestellt. Für gewisse Scheideprobleme ist diese Ausführung ausreichend. Sie ist eine wirtschaftlich vertretbare Lösung.According to a further embodiment of the invention, excitation coils are made of normally conductive material. This version is sufficient for certain vaginal problems. It is an economically viable solution.

Nach einem weiteren Merkmal der Erfindung sind die Erregerspulen aus Supraleitern hergestellt. Schwach magnetische Materialien lassen sich nur mit aus Supraleitern erzeugbaren Magnetfeldern trennen.According to a further feature of the invention, the excitation coils are made from superconductors. Weakly magnetic materials can only be separated using magnetic fields that can be generated from superconductors.

Gemäß einer Ausgestaltung der Erfindung sind zur Erhöhung der magnetischen Induktion oder zur Verringerung der Amperewindungszahl ein oder mehrere Eisenkerne oder Eisenjoche vorgesehen. Ebenso sind zur Abschirmung des magnetischen Feldes ein oder mehrere Eisenjoche oder eine normalleitende oder ein supraleitende Fläche vorgesehen. Der Vorteil dieser beiden Merkmale liegt darin, daß eine Verminderung des Streufeldes und eine Erhöhung des Nutzfeldes dadurch gegeben ist.According to one embodiment of the invention, one or more iron cores or iron yokes are provided to increase the magnetic induction or to reduce the number of ampere turns. Likewise, one or more iron yokes or a normally conducting or a superconducting surface are provided for shielding the magnetic field. The advantage of these two features is that there is a reduction in the stray field and an increase in the useful field.

In der Zeichnung ist an Hand eines Ausführungsbeispieles die Erfindung näher erläutert.In the drawing, the invention is explained in more detail using an exemplary embodiment.

In der Fig. ist eine rotationssymmetrische Erregerspulenanordnung dargestellt, wobei mit 1 die Rotationsachse und mit 2 die Symmetrieebene bezeichnet ist.A rotationally symmetrical excitation coil arrangement is shown in the figure, 1 denoting the axis of rotation and 2 denoting the plane of symmetry.

Die Erregerspulen 3 und 5, die oberhalb der Symmetrieebene 2 angeordnet sind, sind z. B. im positivem Sinn stromdurchflossen, die Erregerspulen 4 und 6, die unterhalb der Symmetrieebene 2 angeordnet sind, sind dementsprechend im negativen Sinn stromdurchflossen. Durch diese gegensinnige Durchflutungsanordnung wird der gesamte magnetische Fluß der oberen bzw. der unteren beiden Spulen zwischen den Spulenpaaren 3, 5 und 4, 6 hindurchgedrückt und erzeugt dadurch im ringkanalförmigen Scheidevolumen 7 eine annähernd konstante Scheidekraftdichte. Die Gegenkraft ist in diesem Beispiel die Fliehkraft, die im ringkanalförmigen Scheidevolumen 7 auf die mit der Transportgeschwindigkeit bewegten Teilchen wirkt. Die Überlagerung der Fliehkraft mit den Schleppkräften in der Trägerflüssigkeit, gemeinsam mit der kleinen radialen Ausdehnung des Scheidevolumens, ergeben eine annähernd räumlich konstante Gegenkraft, sodaß sich für Teilchen einer bestimmten Volumssuszeptibilität Ks durch Einstellung der Durchflußgeschwindigkeit vo (damit der Fliehkraft) und der Größe der magnetischen Induktion (damit der magnetischen Scheidekraft) ein Kräftegleichgewicht unabhängig vom Ort innerhalb des Scheidevolumens erreichen läßt.The excitation coils 3 and 5, which are arranged above the plane of symmetry 2, are, for. B. flowed through in a positive sense, the excitation coils 4 and 6, which are arranged below the plane of symmetry 2, are accordingly flowed through in a negative sense. Through this opposing flow arrangement, the entire magnetic flux of the upper and the lower two coils between the coil pairs 3, 5 and 4, 6 is pushed through and thereby generates an approximately constant cutting force density in the annular channel-shaped cutting volume 7. In this example, the counterforce is the centrifugal force which acts in the annular channel-shaped partition volume 7 on the particles moving at the transport speed. The superimposition of the centrifugal force with the drag forces in the carrier liquid, together with the small radial expansion of the cutting volume, result in an approximately spatially constant counterforce, so that for particles of a certain volume sensitivity Ks by adjusting the flow velocity v o (hence the centrifugal force) and the size of the magnetic induction (thus the magnetic cutting force) can achieve a balance of forces regardless of the location within the cutting volume.

Die magnetische Scheidekraftdichte übt infolge der unterschiedlichen Volumssuszeptibilitäten der zu scheidenden Materialien auf die unterschiedlichen Materialteilchen eine unterschiedliche Kraft aus. Diese magnetische Kraft steht in Konkurrenz zu der für alle Teilchen annähernd gleichen Gegenkraft. Für Materialteilchen mit größerer Volumssuszeptibilität als Ks überwiegt die magnetische Kraft, während für Materialteilchen mit kleinerer Volumssuszeptibilität als Ks die Gegenkraft überwiegt.The magnetic separating force density exerts a different force on the different material particles due to the different volume sensitivities of the materials to be separated. This magnetic force competes with the counterforce, which is approximately the same for all particles. For particulates of greater than Ks Volumssuszeptibilität outweighs the magnetic force, while for particulates smaller than Ks Volumssuszeptibilität outweighs the counterforce.

Wird die Erregerspulenanordnung von der Fig. nicht als rotationssymmetrisches Gebilde betrachtet, sondern als langgestrecktes Gebilde, so ist die Gegenkraft eine Überlagerung der Schleppkräfte im Trägerfluid mit der Schwerkraft.If the excitation coil arrangement is not considered by the figure as a rotationally symmetrical structure, but rather as an elongated structure, the counterforce is a superimposition of the drag forces in the carrier fluid with the force of gravity.

Aus der Fig. ist weiters ersichtlich, daß im allgemeinen das Scheidevolumen zwischen die Erregerspulen zu liegen kommt. Setzt man konstante Stromdichte über die Querschnitte der Erregerspulen voraus, so läßt sich mit einem Spulenpaar mit nicht rechteckigem Querschnitt bzw. mit mehreren Spulenpaaren mit rechteckigem Querschnitt die gewünschte Konstanz der Scheidekraftdichte über das Scheidevolumen bzw. die gewünschte Anpassung an die räumlich veränderliche Gegenkraft erreichen. Bei verwendung von Spulenpaaren mit unterschiedlichen Stromdichten in den einzelnen beliebig geformten Spulenteilquerschnitten läßt sich die gewünschte Konstanz der Scheidekraftdichte über das Scheidevolumen bzw. die gewünschte Anpassung an die räumlich veränderliche Gegenkraft erreichen.It can also be seen from the figure that the volume of the sheath generally lies between the excitation coils. Assuming constant current density across the cross sections of the excitation coils, the desired constancy of the cutting force density over the cutting volume or the desired adaptation to the spatially variable counterforce can be achieved with a coil pair with a non-rectangular cross section or with several coil pairs with a rectangular cross section. When using pairs of coils with different current densities in the individual coil cross-sections of any shape, the desired constancy of the cutting force density over the cutting volume or the desired adaptation to the spatially variable counterforce can be achieved.

Claims (7)

1. A magnetic separator, preferably for the separation of materials having slight differences in magnetic susceptibility, consisting of exciting coils (3, 5 and 4, 6) for producing a magnetic field in the separation volume (7) in which the particles to be separated are exposed to a counter-force and a component of the magnetic force, characterised in that a force equilibrium is produced between the magnetic force and the opposingly directed counter-force on the particles located in the separation volume (7) wherein the magnetic field is induced predominantly by the form and position of the exciting coils (3, 5 and 4, 6).
2. A magnetic separator according to Claim 1, characterised in that the magnetic field is induced by rotationally symmetrical coils (3, 5 and 4, 6) which are arranged symmetrically about the separation volume (7) and are permeated by current in opposing directions with respect to the plane of symmetry (2) and enclose the separation volume (7), and the radius of the centre of the separation volume (7) is smaller than the greatest radius of the exciting coils (5, 6) but greater than the smallest radius of the exciting coils (3,4).
3. A magnetic separator according to Claim 1, characterised in that the magnetic field is induced by elongate coils, the long sides of the coils being arranged symmetrically about a plane of symmetry and enclosing the separation volume arranged symmetrically about the plane of symmetry.
4. A magnetic separator according to at least one of Claims 1 to 3, characterised in that the exciting coils (3, 4, 5, 6) are produced from normally conducting materials.
5. A magnetic separator according to at least one of Claims 1 to 3, characterised in that the exciting coils (3, 4, 5, 6) are produced from superconductors.
6. A magnetic separator according to at least one of Claims 1 to 5, characterised in that one or more iron cores or iron yokes are provided for increasing the magnetic induction or for reducing the number of ampere windings.
7. A magnetic separator according to at least one of Claims 1 to 5, characterised in that one or more iron yokes or a normally conducting or a superconducting area are provided for screening the magnetic field.
EP19850890117 1984-05-22 1985-05-21 Magnetic separator Expired EP0162834B1 (en)

Applications Claiming Priority (2)

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AT1684/84 1984-05-22
AT0168484A AT379525B (en) 1984-05-22 1984-05-22 MAGNETIC CUTTER

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EP0162834A2 EP0162834A2 (en) 1985-11-27
EP0162834A3 EP0162834A3 (en) 1986-02-19
EP0162834B1 true EP0162834B1 (en) 1988-07-27

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WO1990004458A1 (en) * 1988-10-25 1990-05-03 Elin Energieanwendung Gesellschaft M.B.H. An open-gradient magnetic separator
AT400779B (en) * 1989-07-19 1996-03-25 Gerhold Juergen Dipl Ing Dr Te Magnet system
AT393463B (en) * 1990-07-13 1991-10-25 Elin Energieanwendung Isodynamic separating-channel magnetic separator

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DE2157217A1 (en) * 1971-11-18 1973-05-24 Preussag Ag Magnetic separator - utilising supraconducting coil magnet
DE2650528A1 (en) * 1976-11-04 1978-05-18 Kloeckner Humboldt Deutz Ag MAGNETIC CUTTER
GB2064377B (en) * 1979-10-12 1984-03-21 Imperial College Magnetic separators
US4340468A (en) * 1980-11-06 1982-07-20 The United States Of America As Represented By The United States Department Of Energy Method and apparatus for separating materials magnetically

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DE3563916D1 (en) 1988-09-01
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EP0162834A3 (en) 1986-02-19

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