EP0242773B1 - Method for the continuous separation of magnetizable particles, and device therefor - Google Patents

Description

The invention relates to a method for the continuous separation of magnetizable paramagnetic and / or diamagnetic particles from a fluid stream loaded with the particles, which is passed through a separation region penetrated by a high gradient magnetic field along a main flow path, according to the preamble of claim 1.

A non-generic method, which is mainly used for kaolin cleaning, is known, which does not work continuously, but cyclically with high gradient magnetic separators, the magnetizable particles being deposited on the steel wool filling and the latter therefore having to be rinsed cyclically. The processing of substances with a high proportion of magnetizable particles becomes uneconomical due to the short cycle times.

Furthermore, according to a non-generic method, i.e. discontinuous, working high gradient magnetic separators in carousel construction known, which have a complex coil construction and use the volume filled by the magnetic field relatively poorly; In addition, large masses have to be moved through the magnetic coils.

Finally, magnetic separators (OGMS = Open Gradient Magnetic Separation) which do not work according to the generic type (OGMS), which work continuously and in which the field gradients are generated by oppositely excited superconducting coils. However, due to the force densities that are about two orders of magnitude smaller than in a generic method, they are only suitable for separating larger, strongly paramagnetic particles.

A generic method is known from US Pat. No. 4,261,815, which works for continuous magnetic separation with high field gradients. The device of a magnetic separator specified for its implementation consists of a first matrix of wires perpendicular to the magnetic field for generating field gradients and particle deflection and a second grid matrix for separating the particle streams flowing in the wire direction. The first and second matrix form the flow guide matrix, the main problem with this known device in the difficult manufacture of the plurality of thin wires arranged parallel to the axis, the diameter of which is e.g. Is 0.2 mm and their distances from each other e.g. Amount to 2 mm. The high-performance magnetic field passes through the tubular magnetic separator in the transverse direction, the housing of which is accordingly made of non-magnetic material. Due to the difficult arrangement in its interior, a method operating with such a magnetic separator is relatively dirt-prone and therefore susceptible to failure in continuous operation.

A second variant of a flow guide matrix for the deposition process according to the aforementioned US PS is published in the magazine "IEEE Trans. Magn. MAG 19, 2127 (1983) and also consists of a wire grid matrix, the magnetic field being applied perpendicular to the wire direction and In this second variant, the separation of the particles is also mentioned by means of repulsive magnetic forces. The range of attractive forces is covered by plates made of non-magnetizable material. This system, which has been tried and tested on a laboratory scale, meets the requirements of the first variant according to the mentioned US-PS problems mentioned analogously.

Proceeding from the generic method, the object of the invention is to design it in such a way that the problem of the continuous concentration of magnetizable particles in the range of forces of the high gradient magnetic separators can be realized in a more robust and less prone to clogging manner and therefore overall with a better efficiency.

According to the invention, the object is achieved in a generic method according to claim 1 by the features specified in the characterizing part of claim 1.

The advantages that can be achieved with this method can be seen primarily in the fact that relatively robust perforated plates can be used for its implementation for the perforated fields. The introduction of the high gradient magnetic field with its lines of force aligned with the direction of the main flow path or in the axial direction of the polar body orifices enables the use of cylindrical high-performance solenoid coils with an extremely favorable field introduction into the interior of the separation region. The process can be carried out continuously with high throughput and significantly reduced risk of clogging.

The invention also relates to a device for carrying out the method according to claim 1, as described in the preamble of claim 2 and known in principle by the aforementioned US Pat. No. 4,261,815. With this device defined in the preamble of claim 1, the object of creating a particularly advantageous, process- and production-friendly and robust device for carrying out the method according to the invention is achieved according to the invention by the features specified in the characterizing part of claim 2. Advantageous developments of the subject matter of claim 2 are specified in subclaims 3 to 20.

The method according to the invention and the device for carrying it out are explained in more detail below with reference to the drawing, in which several exemplary embodiments are shown.

• Fig. 1 einen vergrößerten Ausschnitt der im Innern eines Trennrohres angeordneten Trennstruktur mit einer aus Polkörper-Mündungen, Polkörper-Wandteilen sowie verbindenden Lochblech-Wandteilen bestehenden Strömungsleit-Matrix und mit korrespondierenden Zufuhr-Lochfeldern;
• Fig. 2 ein zweites Ausführungsbeispiel in einer Fig. 1 entsprechenden Darstellungsweise, wobei die Polkörper-Mündungen nicht als Düsenkörper, sondern als Öffnungen in ebenen Lochblechen ausgeführt sind;
• Fig. 3 perspektivisch und in verkürzter Darstellung ein Trennrohr, welches eine Trennstruktur nach Fig.1 aufweist;
• Fig. 4 einen Querschnitt durch das Trennrohr nach Fig.3 mit eingetragenen Maßangaben zur Verdeutlichung der Größenverhältnisse;
• Fig. 5 ein aus einer Vielzahl von Trennrohren nach Fig. 3 und 4 aufgebauten Trenn-Kanister, perspektivisch, mit zum Teil weggebrochenen Wandteilen;
• Fig. 6 in entsprechender Darstellung zu Fig. 5, jedoch vergrößert eine geringfügig modifizierte Ausführung des Trenn-Kanisters nach Fig. 5;
• Fig. 7 einen vergrößerten Querschnitt durch den Trenn-Kanister nach Fig. 6 und
• Fig. 8 eine Kaskadenschaltung für kontinuierlich arbeitende Hochgradienten-Magnetscheider unter Verwendung dreier unterschiedlich langer Trenn- Kanister nach Fig. 5 bzw. 6.

It shows in a partially simplified, schematic representation:

• 1 shows an enlarged section of the separating structure arranged in the interior of a separating tube with a flow guide matrix consisting of pole body openings, pole body wall parts and connecting perforated plate wall parts and with corresponding feed perforated fields;
• FIG. 2 shows a second exemplary embodiment in a representation corresponding to FIG. 1, the pole body orifices not being designed as a nozzle body but as openings in flat perforated plates;
• 3 is a perspective and shortened representation of a separating tube which has a separating structure according to FIG. 1;
• 4 shows a cross section through the separating tube according to FIG. 3 with entered dimensions to clarify the size relationships;
• 5 shows a separating canister constructed from a plurality of separating pipes according to FIGS. 3 and 4, in perspective, with wall parts broken away in part;
• FIG. 6 in a representation corresponding to FIG. 5, but enlarged a slightly modified embodiment of the separating canister according to FIG. 5;
• Fig. 7 is an enlarged cross section through the separating canister according to Fig. 6 and
• 8 shows a cascade circuit for continuously operating high gradient magnetic separators using three separating canisters of different lengths according to FIGS. 5 and 6.

The device shown in Figures 1 to 8 realizes a method according to claim 1. The core of this device of a continuous magnetic separator is a perforated plate-like fine structure, which serves both for the formation of the magnetic field gradients required for the separation and also leads the partial currents enriched and depleted in magnetizable material.

1, the fine structure of the flow guide matrix has separating perforated fields designated as a whole and feed perforated fields ZL arranged therebetween in the direction of the main flow path z. The pole body orifices 1 and the pole body wall parts 2 delimiting them are formed by a perforated plate-like fine structure with hollow-cone-shaped, projecting nozzles in the hole area. The pole body wall parts 2 consist of ferromagnetic material, the remaining wall parts 3 of the perforated sheet-like fine structure made of non-magnetizable or diamagnetic or weakly paramagnetic material. Another perforated plate-like fine structure for the feed perforated fields ZL has pairs of perforated plates 5 spaced plane-parallel to one another and arranged with their feed openings 4 congruent to the pole body orifices 1, the space 6 between the paired perforated plates 5, 5 serving as the feed zone for the particle-laden fluid flow A.

Also in the flow guide matrix from the separating perforated fields TL, the perforated plates 3 are stacked in pairs, in particular mirror images of one another, so that the pole body openings 1 and the pole body wall parts 2 each lie on a common axis. In the left upper pole body arrangement, the field constriction of the magnetic field, denoted as a whole by H, whose main flow direction points in the direction of the arrow fi, is generated schematically by the pole body designated as a whole by PK. Because of the local rotational symmetry, the field narrowing takes place even more strongly than shown in FIG. 1, namely in two dimensions. To the right of the schematically represented field course, the flow direction of the incoming particle-laden fluid stream A is shown schematically by broken lines. The magnetic forces acting on paramagnetic particles are indicated by arrows Fm and cause a concentration of the paramagnetic particles in the core current flowing into the pole body orifices, while that remaining between the perforated plate 5 and the separating perforated field TL or the associated pole bodies PK and perforated plates 3 Partial stream d depleted of paramagnetic particles. This partial stream d is referred to as the second branch stream and the branch stream p directed into the pole body orifices 1 is referred to as the first branch stream. For diamagnetic particles, the magnetic forces (see arrows Fm), which coincide with the corresponding gradient field, act in the opposite direction, so that there is a depletion of diamagnetic particles in the core stream or first branch stream p.

The perforated plates 5 of the feed perforated fields ZL, like the perforated plate wall parts 3, consist of non-magnetic or diamagnetic or weakly paramagnetic material. They are arranged at a distance a1 from one another and form the feed zone A1 between them. The perforated plates 3 of the flow guide matrix, designated as a whole by PK / 3, are likewise arranged at a distance from one another, which is designated by a2. This spacing gap forms the first collection chamber SK1 for the first branch flows p, which are designated M in the collected form. The flow zone arranged between the perforated plate 5 and the flow guide matrix PK / 3 is a second collecting chamber SK2 for the fraction d (second branch flow) depleted of paramagnetic particles p, and the second branch flows give the total flow NM in the second collecting chamber SK2.

1 shows a variant of the fine structure shown in FIG. 1, which does not work with attractive forces for paramagnetic particles, but with repulsive forces. It consists of two perforated plate pairs 3 ', 3' stacked one above the other, the particle-laden fluid flow A between the thin perforated plate pairs 5 ', 5' of non-magnetizable material is fed and the fraction d depleted of paramagnetic particles is discharged between the thicker perforated plates 3 ', 3' made of ferromagnetic material (collection chamber SK1), whereas the fraction enriched in paramagnetic particles is discharged inside the SK2 collection chamber.

For separation, the magnetic field lines are locally greatly diluted, which leads to repulsive forces on paramagnetic particles, which are correspondingly depleted in the core current d. In contrast, diamagnetic particles are enriched in the core stream. The advantage of this separation structure is the even lower risk of clogging if a certain proportion of ferro- or strongly paramagneti is present in the incoming fluid stream A. This separation structure is also easier to manufacture.

According to FIG. 3, the perforated plates 3 provided with the pole bodies PK or PK 'and the perforated plates 5 having the feed openings 4 can be combined to form modules and stacked to form a separating tube TR. The separating pipe TR is slotted in segments to supply the incoming particle-laden fluid streams (fluid streams can in principle be understood not only as liquid streams but also as gas streams) and to discharge the magnetic and non-magnetic fractions. The feed openings 4 and the polar body orifices 1 or nozzles are each one above the other in a hexagonal grid arrangement.

FIG 4 shows, for example, favorable dimensions for a single separating tube (in millimeters).

A large number of separation tubes of the type shown in FIG. 3 can be combined to form a separation canister, as is shown in perspective in FIG. 5 or in FIG. 6, which together with the solenoid surrounding the separation canister and the (not shown in more detail) Supply units forms the magnetic separator.

According to FIG. 5, the particle-laden fluid stream is fed to the separating canister TK via the pipe socket 11 of a main feed line and fed to each separating pipe TR from three sides via a flow inlet plate 10 and the pipe spaces 20, while the non-magnetic fraction is discharged separately from one another via the other pipe spaces. The intermediate plate 30 (flow guide plate) separates the two fractions in such a way that the channels leading the magnetic fraction end above and the channels leading the non-magnetic fraction below the intermediate plate 30. The first and second main collecting lines 60 and 70 for discharging the two fractions are welded into the intermediate plate 30 and into the base plate 40 with their corresponding pipe connections.

The six packing elements 50 resulting from the hexagonal arrangement of the separating tubes TR can be used as a pipeline in a cascade connection, compare FIG. 8, the magnetic separator consisting of several separating canisters in the magnetic field of a solenoid S.

The cross section according to FIG. 7 shows the separating pipes TR arranged in a hexagonal grid within the separating canister, an individual separating pipe being shown in more detail.

Both the separating pipe TR shown in FIGS. 3 and 4 and the separating canister TK shown in FIGS. 5 to 7 with their main flow paths z can be regarded as separator containers in the sense of the invention. 1, 3 and 4. The slots formed by the stacking in the direction z of the modules M01 and M02 (see FIG. 1) are formed by the radially-axially extending bulkheads 9 on the outer circumference 7 of the separating tube TR divided into three groups of slots: first slots 8.1 for supplying the fluid flow to the feed zones AO of the modules from a feed line. The feed line function is performed by the line volumes vi, v ₂ and vs, which have the shape of columns with a ring-sector-shaped cross section and are each delimited between two bulkhead walls 9 which follow one another in the circumferential direction. In the exemplary embodiment shown, the bulkhead walls 9 are arranged hexagonally, ie they lie on radii which span sectors with a sector angle of 60 _° between them. The three line volumes vi, v ₂ and v ₃ are evenly distributed over the circumference of the separating tube. Between the line volumes v _i and v ₂ , the line volume v _{4 is} directly adjacent and communicating with or with the second slots 8.2 for discharging the first branch flows M collected in the first collecting chambers SK1 of the modules (FIG. 1). In the case of the second exemplary embodiment According to FIG. 2, the first branch streams are designated NM by definition, but this will still be discussed. The dashed line indicates within the line _{volume V4} the exit of the first partial flows M collected in the respective modules. Seen in the clockwise direction, the line volume v _{2 is} followed by the line volume vs, followed by the line volume v ₃ and then the line volume vε. The line volumes v ₅ and v ₆ are arranged adjacent to and communicating with the third slots 8.3, that is, they serve as a collecting line for the second partial flows NM radially emerging from the respective modules, as indicated by the dashed flow line in the right part of FIG. 3 . These manifolds vs and v ₆ therefore communicate with the second manifolds SK2 (see FIG. 1).

Returning to the detailed illustration according to FIG. 1, it can be seen that the incoming particle-laden fluid stream A per hole 4 is divided into the partial streams d + p, each of which contains para- and diamagnetic particles, via the feed zone AO and the respective feed hole field ZL. The main flow direction z and the main field direction of the high gradient magnetic field H coincide or run parallel to one another; The local gradient fields H1 already mentioned are then generated by the polar bodies PK because the magnetic field lines preferably enter these ferromagnetic bodies, so that the constrictions and field line densifications shown in FIG. 1 result. For the sake of simplicity, for the following considerations, the first paramagnetic particle group as well as the partial stream enriched with it are denoted by p and the second diamagnetic particle group as well as the partial stream enriched with it are designated by d. If the first particle group p is assigned a first magnetic susceptibility ic1 and the second particle group d is assigned a second magnetic susceptibility _K2 , which are different from one another and also with respect to the magnetic susceptibility _{KF of} the fluid or carrier fluid, then one can use the local gradient fields H1 the polar body PK is different for each of the two groups of particles exert strong magnetic deflection forces due to different magnetic dipole moments. To achieve this deflection process, which has already been explained, the flow guide matrix PK / 3 is now formed by at least one separating hole field TL over the cross section of the separating region of pole body orifices 1 and associated ferromagnetic pole body wall parts 2 of a flow guide body. The main magnetic flux H runs, as mentioned, in the axial direction 1.0 of the pole body orifices 1 and thus parallel to the main flow path or the main flow direction z. Upstream and at a distance a3 from the flow guide matrix PK / 3 there is at least one feed perforated plate ZL of another flow guide body, the feed openings 4 of which correspond to the pole body orifices 1 and in particular are arranged coaxially therewith. The perforated feed plate ZL, which acts as a flow guide body, divides the fluid stream A flowing in from the outer circumference of the separation region via feed zones vi, v ₂ , _V3 (compare (FIG. 3)) into the pole body orifices 1 and divides the partial streams p + d. The outlet side communicates at least one first collecting chamber SK1. The flow volume between the perforated feed plate ZL of the diamagnetic flow guide body and the separating perforated field TL of the pole body wall parts 3 serves as a second collecting chamber SK2. The first collecting chamber SK1 is connected to a collecting line v ₄ ( 3), and the second collecting chamber SK2 is connected to the other collecting line vs, v _6. At least two collecting lines, one for the first branch flow p and one for the second branch flow d, are required, as will be explained further below , are then in the context of the union of a plurality of separation tubes TR according to FIG 3 to a separation canister TK ten bus lines _{V4 connected} to the first main bus line 60 and the second bus lines v ₅ , v ₆ to the second main bus line 70 or communicate with these main lines.

It can be seen from FIG. 1 and FIG. 3 that the polar body orifices 1 and wall parts 3 of the respective separating perforated field TL are formed by a perforated plate-like fine structure with hollow-cone-shaped, projecting nozzles PK in the perforated area and the field line compression in the area of the nozzle orifices 1 local Gradient fields H1 result which exert attractive forces on paramagnetic particles flowing in the direction of the nozzle axis 1.0, see arrows F _m , and repulsive forces on correspondingly flowing diamagnetic particles d, so that the core branch flow p entering paramagnetic through the nozzles PK or pole body Particles is enriched, on the other hand, the other or second branch stream d flowing past the nozzles PK is depleted of paramagnetic particles and enriched on diamagnetic particles. The boundary edges 1.1 of the pole body or nozzle orifices 1 are, as shown, rounded, which is favorable in relation to the field line and the flow resistance and thus improves the degree of separation. The feed openings 4 of the feed perforated plate ZL are each arranged coaxially with the pole body openings 1 of the separating perforated field TL. In particular, a perforated sheet-like fine structure is provided for the pole body orifices 1 and the pole body wall parts 3 of the flow guide matrix PK / 3, each in pairs with a plane-parallel spaced apart (distance a2) and congruent arrangement of the two paired perforated sheets 3-3, the space between the paired perforated plates 3-3 serves as a collecting chamber SK1 of the first branch flows p and the space lying outside the perforated plates and adjacent to the feed perforated fields ZL serves as a second collecting chamber SK2 for the second branch flows d. According to FIG. 1, the flow guide body for the feed perforated field ZL is also designed as a perforated plate-like fine structure, specifically with a spaced plane-parallel spacing (distance a1) and congruent arrangement of the two paired perforated plates 5-5, the space between the paired perforated plates 5-5. 5 serves as the feed zone AO.

In itself, a separating effect can already be achieved if a feed perforated field ZL with a single perforated plate 5 is assigned to a separating perforated field TL with a single perforated plate 3 with pole bodies PK on its pole body side. Here as in the following, however, the separation module is to be understood as the smallest, satisfactorily functioning basic unit M01, which is arranged axially several times in the context of a separation tube TR in the main flow direction z. Each of these separating modules M01 consists of a perforated plate pair 3-3 for the flow guide matrix PK / 3 and a perforated plate 5 for the feed perforated fields ZL, which is arranged on both sides of this perforated plate pair at a distance a3 in mirror image. These modules M01, one of which can be seen in full in FIG. 1, are stacked at intervals a1 such that the feed-in zones AO are formed by the perforated plates 5 of the feed perforated fields ZL of the successive modules which are adjacent to one another. The separation module M02 can also be regarded as the smallest module unit that repeats itself several times or repeatedly in the stacking direction, each consisting of a perforated plate pair 5-5 for the feed zones AO and a perforated plate arranged in mirror image at a3 distance on both sides of this perforated plate pair 5 for the TL perforated panels. These modules M02 are stacked analogously to the modules M01 at intervals a2 such that the first collecting chambers SK1 are formed by the perforated plates 3-3 of the perforated panels TL of the successive modules which are adjacent to one another. This stacked arrangement of the individual modules M01 and M02 results in the double-flow inflow in direction z and in direction -z and also a double-flow outflow in these two directions, which results in very good utilization of the volume of a separating pipe TR (FIG. 3). Such a separating tube TR preferably has a circular cross section, so that the perforated fields or perforated plates ZL, TL, as can be seen from FIG. 3, also have a circular base have crack. 3, the separation modules M01 and M02 are stacked one above the other in the direction z and mechanically fixed to each other to form the separation tube TR (corresponding screw or weld connections are not shown in detail), the separation modules being separated from the tube wall 7 on their outer circumference are surrounded, this tube wall 7 being provided with the slots 8.1, 8.2, 8.3, as already explained.

The basic principle of the perforated plate arrangement explained with reference to FIG. 1 has also been retained in the second exemplary embodiment according to FIG. There, the pole body orifices 1 'and wall parts 3' of a separating perforated field TL are each formed by a perforated plate-like fine structure in such a way that the field line thinning in the perforated region results in local gradient fields H2 which repulsive to para-magnetic particles p flowing in the direction of the perforated axis 1.0 Forces and exert attractive forces on correspondingly flowing diamagnetic particles d, as symbolized by the arrows Frn, so that the core branch flow d 'flowing through the pole body orifices 1' is enriched in diamagnetic particles, whereas the one flowing past the pole body orifices 1 'is enriched Branch stream p is depleted in diamagnetic particles or enriched in paramagnetic particles. Analogously to the first exemplary embodiment according to FIG. 1, it is also advantageous in this case to round off the hole-delimiting edges 1.1 ', as shown, on the inflow and outflow sides. The isolating modules analogous to FIG. 1 are designated here with M01 'or M02'. A separation tube TR can then be constructed from these individual separation modules in a manner corresponding to the arrangement according to FIG. 3. The advantage of such a separating tube from the modules M01 'or M02' is, in particular, that the production of the flow guide matrix PK / 3 'is cheaper than that of the flow guide matrix according to FIG. 1, because as the polar body PK' only the parts that remain standing serve a ferromagnetic perforated plate and special nozzle bodies are not provided here.

As already indicated, a single separation tube TR is shown in FIG. 3 if it is provided with a suitable housing for supplying the particle-laden fluid streams A and for discharging the two fractions M (enriched in paramagnetic particles p) and NM (enriched in diamagnetic particles), already functional, but more for laboratory or experimental use. For commercial purposes, it is recommended, according to FIGS. 5 to 7, that a plurality of separating pipes TR are combined in an axially parallel arrangement to form a separating pipe field and together with a container 100 surrounding the separating pipe field, which has at least one common main feed line 11 on the top side and first and bottom side has second main manifolds 60, 70, is combined to form a separating canister TK. The designs according to FIG. 5 and FIG. 6 are almost identical except for the fact that the main feed line 11 in FIG. 5 is connected centrally to the separating canister, but according to FIG. 6 is eccentric to its axis of rotation. 5 to 7, a high-performance solenoid or magnet MM is not shown; it goes without saying that such a high-performance magnet, arranged separating canister, can also be arranged around a single separating canister according to FIGS. 5 to 7, so that its field lines the multiple arrangement of the separating tubes TR inside the separating Push the canister TK through essentially in the axial direction.

It can be seen in particular from FIGS. 6 and 7 that the separating pipes TR are arranged in a hexagonal grid and that the gusset alleys remaining free between these separating pipes are divided by the bulkhead walls 9 into feed or collecting pipes 20, the feed pipes being separated by the pipe _{volumes V1} to v _{3 are} formed and the first collecting lines through the line volumes v ₄ and the second collecting lines through the line volumes v ₅ , _V6 (cf. FIG. 3). The loaded fluid stream A is fed through the cover-side main feed line 11 of a prechamber 12 of the separating canister TK and from there via feed openings 10.1 provided in a correspondingly perforated flow guide plate 10, the outline of which corresponds to the cross section of the gusset spaces 20 between the separating pipes TR and bulkheads 9, all feed lines vi, v ₂ , _V3 fed in parallel. At the bottom of the separating canister TK, two further, axially adjacent downstream chambers 13, 14 are provided (FIG. 6), which via the gusset-shaped outlet openings 30.1 and 31.1 of the perforated flow deflection plates 30, 31 with the first and second manifolds v ₄ and vs, respectively, v ₆ communicate and open into the first and second main manifold 60 for the M fraction and 70 for the NM fraction.

The outer support structure for the separating canister TK according to FIG 5 to 7 has been omitted for reasons of clarity.

This also applies to the schematic representation according to FIG. 8 of a separator cascade with three separating canisters TK1, TK2 and TK3, which are arranged one above the other in axial alignment and are surrounded by a high-performance magnet MM with magnet coil S. In this fifth exemplary embodiment, the particle-laden, partial fluid stream A1 to be prepared is fed to the first canister TK1 as a mixture of the fresh fluid stream A and a fluid stream M2 + NM3 conveyed back from the outlet of the cascade. The collected second branch flows NM1 from this first canister TK1 are fed via line nm12 from the pump P12 as feed fluid stream A2 to the downstream second canister TK2. The collected first branch flows M1 from the first canister TK1, on the other hand, are fed to the third canister TK3 via line m13 through the pump P13 as feed fluid flow A3. The collected second branch streams NM2 from the second canister TK2 and the collected first partial streams M3 from the third canister TK3 are fed via the lines nm2 or m2 as waste stream NM or as useful stream M to their utilization. The collected first branch streams M2 from the second canister TK2 and the collected second branch currents NM3 from the third canister TK3 are brought together via the two lines m2 and nm3 and fed into the return line nmm31, and this feedback current is fed into the line 11 by the pump P31 as a mixed flow M2 + NM3 and mixed into the raw feed current A.

• - einen ersten Zweigstrom p (FIG 1) bzw. d (FIG 2), auf welchen von dem Gradientenfeld der Polkörper PK (FIG 1) bzw. PK' (FIG 2) attraktive Kräfte in Richtung auf die Polkörper-Mündungen 1 bzw. 1' ausgeübt werden,
• - und in einen zweiten Zweigstrom d (FIG 1) bzw. p (FIG 2), auf welchen von dem Gradientenfeld H1 der Polkörper PK (FIG 1) bzw. von dem Gradientenfeld H2 der Polkörper PK' (FIG 2) repulsive Kräfte in einer Richtung weg von der jeweiligen Polkörper-Mündung 1 bzw. 1' ausgeübt werden.

Returning to the two exemplary embodiments according to FIGS. 1 to 3, in which the essence of the invention is shown, it becomes clear that the invention realizes a method according to which the particle-laden fluid stream A of the separation region is supplied in each case via feed zones supplied from the outer periphery of the separation region AO and through the cross-section of the separation region in the form of at least one feed perforated field ZL, feed openings 4 of flow guide bodies are supplied as a plurality of particle streams d + p. The partial currents d + p are then within the separation region via at least one separation hole field TL of pole body orifices 1 and 1 'distributed over the cross section of the separation region and associated wall parts 2 and 3' of ferromagnetic pole bodies PK and PK 'as flow control Matrix directed. These pole bodies are penetrated by the main magnetic flux H in the direction of their outlet axes 1.0, and they divide the partial streams containing partial streams 1 and 1 ′, which correspond to the respective adjacent feed openings 4, into the at least two branch streams:

• a first branch flow p (FIG. 1) or d (FIG. 2), on which from the gradient field the pole body PK (FIG. 1) or PK '(FIG. 2) attractive forces in the direction of the pole body orifices 1 or 1 'are exercised
• - And in a second branch flow d (FIG. 1) or p (FIG. 2), on which of the gradient field H1 the pole body PK (FIG. 1) or of the gradient field H2 of the pole body PK '(FIG. 2) repulsive forces in one Direction away from the respective pole body mouth 1 or 1 'are exercised.

The first branch flows p (FIG. 1) or d (FIG. 2) flowing through the pole body orifices 1 or 1 'and enriched on the first group of particles become first collection chambers which communicate with the pole body orifices 1 and 1' on the outlet side SK1 forwarded. The second branch flows d (FIG. 1) and p (FIG. 2), deflected by the polar body orifices 1 and 1 'and enriched on the second group of particles, are each fed to second collection chambers SK2, which each contain the flow volume in the separation region between the Include feed hole field ZL and the separation hole field TL without the first branch flows p (FIG. 1) or d (FIG. 2) entering the pole body orifices 1 or 1 '. Finally, the first and second branch flows M and NM brought together in the first and second collecting chambers SK1, SK2 are fed to the at least one first and the at least one second collecting line v ₄ and vs, vε, respectively.

The method according to the invention and the device for its implementation are suitable, inter alia, for kaolin purification, ore processing, concentration of gold, uranium and cobalt from tailings heaps, pyrite separation from coal (also siderite and calcite), for coal cleaning during liquefaction, for the recovery of catalyst material in hydrogenation plants, for the recovery of steel particles from waste water and process dusts in steel plants, to name just a few applications.

The production of perforated plates 3, 5, 3 ', 5' for the separating perforated fields TL and feed perforated fields ZL is possible with very good precision through material processing using laser beams.

Claims (20)

1. Method for the continuous separation of magnetizable para- and/or diamagnetic particles from a fluid flow (A) laden with the particles, which fluid flow is guided through a separation region, penetrated by a high gradient magnetic field (H), along a main flow path (z), wherein the high gradient magnetic field (H) is generated by a plurality of ferromagnetic pole bodies (2) which are arranged inside the separation region in a flow guiding matrix and are penetrated by the magnetic flux of an external high power magnet, and which transform the main magnetic flux of the external high power magnet into a plurality of partial fluxes with non-homogeneous field distribution, corresponding to the number and arrangement of said ferromagnetic pole bodies, and wherein the fluid flow (A) contains at least two groups of particles whose respective magnetic susceptibilities _X1 or _X2, in relation to the magnetic susceptibility _XF of the fluid, differ from one another such that, due to differently sized magnetic dipole moments of the particles in the fluid flow of the separation region, one group of particles in a respective first branch flow (p or d) is deflected in the direction of increasing field gradients and the other group is deflected in a second respective branch flow (d or p) in the direction of decreasing field gradients or at least one group, as the first branch flow (p), is deflected to a greater extent than the other group, as the second branch flow (d), in the direction of increasing or decreasing field gradients, and wherein further both the at least two branch flows (p, d) are separated from one another and the first branch flow (p) enriched with the first group of particles is supplied to a first collecting line (60) and the second branch flow enriched with the second group of particles is supplied to a second collecting line (70), characterised

- in that the particle-laden fluid flow (A) is guided in the form of a plurality of partial flows (d + p) to the separation region, in each case via feed zones (AO) supplied from the outer periphery of the separation region and through feed openings (4) of flow guiding bodies distributed over the cross-section of the separation region in the form of at least one feed hole field (ZL),

- in that the partial flows (d + p) are then guided inside the separation region over at least one separation hole field (TL) of pole body orifices (1; 1') distributed over the cross-section of the separation region and associated wall parts (2) of ferromagnetic pole bodies (PK; PK') as a flow guiding matrix, penetrated by the main magnetic flux (H) in the direction of the axes (1.0) of their orifices and dividing each of the partial flows containing at least two groups of particles into the at least two branch flows with their pole body orifices (1; 1') corresponding to the respectively adjacent feed openings (4):

- a first branch flow (p or d) upon which attractive forces are exerted from the gradient field of the pole bodies (PK) in a direction towards the pole body orifices (1; 1'),

- and a second branch flow (d or p) upon which repulsive forces are exerted from the gradient field of the pole bodies (PK) in a direction away from the respective pole body orifice (1; 1'), and

- in that the first branch flows (p or d) flowing through the pole body orifices (1; 1' ) and enriched with the first group of particles are supplied to first collecting chambers (SK1) communicating on the outlet side with the pole body orifices (1; 1')

- and in that each of the second branch flows (d or p) deflected by the pole body orifices (1; 1') and enriched with the second group of particles are supplied to second collecting chambers (SK2) each of which enclose the flow volume in the separation region between the feed hole field (ZL) and the separation hole field (TL) without the first branch flows (p or d) entering in the pole body orifices(1;1'),

- and in that, finally, the first and second branch flows (M or NM), each reunited in the first and second collecting chambers (SK1, SK2), are supplied to at least one first or to at least one second collecting line (v₄ or v₅, vε).

2. Apparatus for implementing the method according to claim 1, comprising at least one separator vessel (TR, TK) through which the fluid flow Ptd) (sic) laden with particles at least of one first group and one second group may continuously flow along a main flow path (z), and which has at one end of the flow path at least one connection (11) for feeding the fluid flow and at the other end of the flow path a fluid flow outlet divided into at least two collecting lines (v₄ or vs, vs; 60 or 70), one collecting line (v4; 60) transporting the fluid flow fraction (M) enriched with one particle group and the other collecting line (vs, vε; 70) transporting the fluid flow fraction (NM) enriched with the other particle group, and comprising at least one separation region inside the vessel (TR; TK); comprising a plurality of ferromagnetic pole bodies (PK; PK') disposed inside the separation region in a flow guiding matrix (PK/3; PK'/3') to generate a high gradient magnetic field (H), and comprising an arrangement of flow guiding walls (3; 3') forming part of the flow guiding matrix along with the pole bodies (PK; PK') to divide the at least two branch flows (p or d) deflected to different extents at the gradient fields of the pole bodies (PK; PK') to the associated collecting lines, further comprising a high power magnet (MN) disposed at the outer periphery of the separator vessel (TR; TK), the main magnetic flux of which penetrates the separation region and the pole bodies (PK; PK') located therein, producing non-homogeneous partial flows at the individual pole bodies, the first particle group (p or d) having a first magnetic susceptibility _X1 and the second particle group (d or p) having a second magnetic susceptibility x₂, which susceptibilities _X1, _X2, in relation to the magnetic susceptibility x_F of the fluid, differ such that magnetic deflection forces of different strengths are exerted by the gradient fields (H) of the pole bodies (PK; PK') upon the two groups of particles, due to different magnetic dipole moments, characterised

- in that the flow guiding matrix (PK/3; PK'/3') is formed by at least one separation hole field (TL) of pole body orifices (1; 1') distributed over the cross-section of the separation region and associated ferromagnetic pole body wall parts (2; 3') of a flow guiding body,

- in that the main magnetic flux is oriented in the axial direction (1.0) of the pole body orifices (1; 1'),

- in that at least one feed hole plate (ZL) of a further flow guiding body is disposed upstream and at a distance (a3) from the flow guiding matrix, the feed openings (4) of which correspone with the pole body orifices (1; 1'), and which divides the fluid flow (A) flowing to it from the outer periphery of the separation region via feed zones into partial flows (p + d) flowing to the pole body orifices (1; 1'),

- in that at least one first collecting chamber (SK1) communicates with the pole body orifices (1; 1') on the outlet side,

- in that the flow volume between the feed hole plate (ZL) of the diamagnetic flow guiding body and the separation hole field (TL) of the pole body wall parts (3; 3') serves as a second collecting chamber (SK2),

- and in that the first collecting chamber (SK1) is connected to one, and the second collecting chamber (SK2) is connected to the other of the at least two collecting lines (v₄/60 or v₅, vε, 70).

3. Apparatus according to claim 2, characterised in that the pole body orifices (1') and pole body wall parts (3') of a separation hole field (TL) are in each case formed by a fine structure in the form of a perforated plate and the field line attenuation in the hole region produces local gradient fields (H2) which exert repulsive forces upon paramagnetic particles inflowing in the direction of the hole axis (1.0) and attractive forces onl correspondingly inflowing diamagnetic particles, so that the core branch flow (d) flowing through the pole body orifices (1') is enriched with diamagnetic particles, whereas the branch flow (p) bypassing the pole body orifices (1') is depleted of diamagnetic particles or is enriched with paramagnetic particles.

4. Apparatus according to claim 3, characterised in that the hole limiting edges (1. 1') are rounded on the inflow and outflow side.

5. Apparatus according to claim 2, characterised in that the pole body orifices (1) and pole body wall parts (3) of a separation hole field (TL) are formed by a fine structure, in the form of a perforated plate, with hollow conical protruding nozzles (PK) in the hole region and the field line concentration in the region of the nozzle orifices produces local gradient fields (H1) which exert attractive forces on paramagnetic particles inflowing in the direction of the nozzle axis (1.0) and repulsive forces on correspondingly inflowing diamagnetic particles, so that the core branch flow (p) entering through the nozzles (PK) is enriched with paramagnetic particles, whereas the other or second branch flow (d) bypassing the nozzles is depleted of paramagnetic particles and enriched with diamagnetic particles.

6. Apparatus according to claim 5, characterised in that the limiting edges (1.1) of the nozzle orifices (1) are rounded.

7. Apparatus according to one of claims 2 to 6, characterised in that the feed openings (4) of the feed hole plate (ZL) are arranged on the same axis as the pole body orifices (1; 1') of the separation hole field (TL).

8. Apparatus according to one of claims 2 to 6, characterised in that a fine structure in the fcrm of a perforated plate for the pole body orifices (1; 1') and pole body wall parts (3; 3_') of the flow guiding matrix (PK/7; PK') is provided in each case in pairs with the two paired perforated plates (3-3 or 3'-3') arranged so as to be mutually spaced apart in plane parallel manner and congruent, and in that the intervening space between the paired perforated plates serves as the collecting chamber (SK1) of the first branch flows (p or d) and the space lying outside the perforated plates and adjoining the feed hole fields (ZL) serves as the second collecting chamber (SK2) for the second partial flows (d or p).

9. Apparatus according to one of claims 2 to 8, characterised in that the flow guiding body for the feed hole field (ZL) is also a fine structure in the form of a perforated plate.

10. Apparatus according to claim 8 or 9, characterised in that a fine structure in the form of a perforated plate for the feed hole field (ZL) is provided in each case in pairs with the two paired perforated plates (5-5 or 5'-5') arranged so as to be mutually spaced apart in plane parallel manner and congruent, and in that the intervening space between the paired perforated plates serves as a feed zone (AO).

11. Apparatus according to one of claims 8 or 10, characterised in that a plurality of identical separation modules (Mo 1), each consisting of a perforated plate pair (3-3 or 3'-3') for the flow guiding matrix (PK/3 or PK'/3') and a perforated plate (5 or 5') disposed on each of the two sides of this perforated plate pair for the feed hole fields (ZL), are stacked one on top of the other at distances (a1) apart such that the feed zones (AO) are formed by the mutually adjacent perforated plates of the feed hole fields (ZL) of successive modules.

12. Apparatus according to one of claims 8 or 10, characterised in that a plurality of identical separation modules (Mo 2), each consisting of a perforated plate pair (5-5 or 5'-5_') for the feed zones (AO) and a perforated plate disposed on each of the two sides of this perforated plate pair for the separation hole fields, are stacked one on top of the other at distances (a2) apart such that the first collecting chambers (SK1) are formed by the mutually adjacent perforated plates (3 or 3') of the separation hole fields (TL) of successive modules.

13. Apparatus according to claim 11 or 12, characterised in that the outer periphery of the stacked separation modules is surrounded by a tubular wall (7), forming a separation tube (TR).

14. Apparatus according to one of claims 1 to 13, characterised in that the hole fields or perforated plates (ZL, TL) are circular in outline.

15. Apparatus according to claim 14, characterised in that the shell (7) of the separation tube (TR) is provided in segments with slits (8) located along peripheral lines, in accordance with the number and arrangement of the modules (Mo 1 or Mo 2) contained therein:

first slits (8.1) for feeding the fluid flow to the feed zones (AO) of the modules from a feed line,

second slits (8.2) for removing the first branch flows (M or NM) collected in the first collecting chambers (SK1) of the modules to the first collecting line and

third slits (8.3) for removing the second branch flows (NM or M) collected in the second collecting chambers (SK 2) of the modules to a second collecting line.

16. Apparatus according to claim 15, characterised in that the first to third slits (8.1, 8.2, 8.3) are disposed hexagonally and are in each case distributed in several slit groups over the periphery of the separation tube (TR), the slits of each slit group being located one above the other and extending over about one sixth of the periphery of the separation tube.

17. Apparatus according to claim 16, characterised in that three sector arc sections distributed over the periphery of the separation tube are associated with the first slits (8.1) in accordance with the inflowing or outflowing quantities of the fluid flow, and in that of the remaining sector arc sections, one sector arc section is associated with the second slits (8.2) and two sector arc sections are associated with the third slits (8.3).

18. Apparatus according to claim 16 or 17, characterised in that bulkhead partitions (9) which lie in radially-axially extending planes are secured at the outer periphery of the separation tube (TR), forming a seal, and these, in accordance with the hexagonal arrangement of the slits, divide an annular chamber volume at the outer periphery of the separation tube into six different line volumes (vi-v₆), three of which line volumes vi-vs) communicate with the first slits (8.1) and form feed lines, one line volume (v₄) communicates with the second slits (8.2) and forms a first collecting line and two further line volumes (vs, vs) communicate with the third slits (8.3) and form second collecting lines.

19. Apparatus according to one of claims 16 to 18, characterised in that a plurality of separation tubes (TR) is combined in axially parallel arrangement to form a separation tube field and together with a vessel (100) surrounding the separation tube field which has at least one common main feed line (11) at its top and first and second main collecting lines (60, 70) at its base, is combined to form a separation canister (TK) which is surrounded by a high power solenoid (MM) to generate the high gradient magnetic field (H), the narrowing gaps left clear between the separation tubes (TR) arranged in a hexagonal grid being divided by the bulkhead partitions (9) into feed or collecting lines (20) and the laden fluid flow (A) being supplied via the main feed line (11) at the top to a forechamber (12) of the canister and from there via a correspondingly perforated flow feed plate (10) in parallel to all the feed lines (v_i-v₃), while two further axially adjacent afterchambers (13, 14) are provided at the base of the canister, these communicating with the first or second collecting lines (v₄ (sic) or v₅, v₆) via perforated flow outlet guiding plates (30, 31) and opening into the first or second main collecting line (60 or 70).

20. Apparatus according to claim 19, characterised in that several separating canisters (TK) are connected together to form a separator cascade, wherein the collected second branch flows (NM 1) may be supplied from a first canister (TK 1) as a feed fluid flow (A2) to a second canister (TK 2), the collected first branch flows (M1) may be supplied from the first canister (TK 1) to a third canister (TK 3) as a feed fluid flow (A3), the collected second branch flows (NM 2) from the second canister and the collected first partial flows (M3) from the third canister may be utilized as a waste flow or as a useful flow, and wherein finally the collected first branch flows (M2) from the second canister (TK 2) and the collected second branch flows (NM3) from the third canister (TK3) may be united and supplied to the main feed line of the first canister (TK 1) again as a feed fluid flow (A1).

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