Magnetic separation unit, system and method
Patent Information
- Application Number
- PCT/AU2026/050353
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-04-14
- Filing Date
- 2026-04-13
- Publication Date
- 2026-10-22
Smart Images
Figure AU2026050353_22102026_PF_FP_ABST
Abstract
Description
Magnetic Separation Unit, System and Method Related Applications
[0001] The invention claims priority from Australian provisional patent application no.2025901278 filed on 14 April 2025, the contents of which are incorporated by reference.Technical Field
[0002] The invention relates to a magnetic separation unit, system and method. In particular, the invention relates to a magnetic separation unit, system and method for the separation of bulk material that includes magnetic and non-magnetic constituents.Background
[0003] The separation of magnetic and non-magnetic constituents from a bulk material such as a bulk mined material may be conducted using a magnetic separator. Such magnetic separators may take various forms such as being in the form of a drum or ring arranged vertically or horizontally. However, fundamentally, such magnetic separators all use magnets to selectively magnetise a substate to which magnetic constituents are selectively attracted or released to achieve material separation.
[0004] For separating minerals from a bulk mined material such as mineral sands, magnetic separators such as high-intensity types like wet high-intensity magnetic separators (WHIMS) and rare earth roll magnetic separators may be used to extract weakly magnetic minerals like ilmenite, hematite, and garnet, enhancing recovery and purity.
[0005] A WHIMS separator may be generally ring-shaped with a series of coils spaced apart generally about an outer circumference of the ring. A magnetisable substate in the form of a series of magnetisable plates may be arranged to rotate inwardly of the series of coils which are selectively magnetised and demagnetised to attract and release magnetic constituents fed to the plates.
[0006] The arrangement is adapted to create null zones, with magnetic material washes, in which the plates are relatively demagnetised allowing separation of magnetic constituents, and active zones, with non-magnetic material washes, in which the plates are relatively magnetised to allow separation of the non-magnetic constituents.
[0007] Problems with magnetic separators such as the WHIMS separator may include scalability, footprint, weight, and associated costs.
[0008] The invention disclosed herein seeks to overcome one or more of the above identified problems or at least provide a useful alternative.Summary
[0009] In accordance with a first aspect there is provided, a magnetic separation unit for separating a material having magnetic constituents and non-magnetic constituents, the unit including a matrix adapted to receive the material, a shield arrangement associated with a passage through which the matrix may pass, and a coil arrangement having at least one coil arranged to extend at least partially around the shield arrangement to generate a magnetic field generally along the passage in a direction of travel of the matrix, wherein the coil arrangement and the shield arrangement are configured to provide the unit with an active zone, outside the shield arrangement, in which a portion of the matrix is magnetisable so as to attract the magnetic constituents thereto, and a null zone adjacent the active zone, in which the portion of the matrix is magnetically shielded by the shield arrangement, the shield arrangement creating a bypass for the magnetic field around the portion of the matrix such that the portion of the matrix becomes relatively demagnetised to allow release of the magnetic constituents.
[0010] In an aspect, the matrix is provided in the form of a carriage arrangement adapted to receive and transport the material.
[0011] In a further aspect, the at least one coil extends around the shield arrangement.
[0012] In a further aspect, the at least one coil is arranged generally perpendicularly to the direction of travel of the matrix.
[0013] In a further aspect, the magnetic field is generated generally in line with the direction of travel of the matrix.
[0014] In a further aspect, the null zone is at least partially defined within the shield arrangement.
[0015] In a further aspect, the active zone is located immediately adjacent and outside the shield arrangement.
[0016] In a further aspect, wherein the shield arrangement is provided in the form of a hollow core block.
[0017] In a further aspect, the hollow core block may be comprised of one or more plates.
[0018] In a further aspect, the unit includes a plurality of block arrangements, each of the block arrangements including a hollow core block adapted to provide the null zone.
[0019] In a further aspect, the shield arrangement includes spaced apart walls between which the matrix passes so as to define the passage.
[0020] In a further aspect, the walls are formed of a magnetisable material so as to preferentially direct the magnetic field around the portion of the matrix in the null zone.
[0021] In a further aspect, the shield arrangement is arranged to enhance the magnetic field in the direction of travel of the matrix.
[0022] In a further aspect, the coil arrangement includes two or more spaced apart coils with a gap therebetween.
[0023] In a further aspect, the shield arrangement bridges the gap and extends between the two or more spaced apart coils.
[0024] In a further aspect, the unit includes a magnetic material collector located at or proximate the null zone.
[0025] In a further aspect, the null zone includes a magnetic wash arrangement that produces a stream of water or air that assists the dislodgement of the magnetisable material from the matrix.
[0026] In a further aspect, the unit includes a non-magnetic material collector located at or proximate the active zone.
[0027] In a further aspect, the non-magnetic material collector is located immediately prior to the shield arrangement.
[0028] In a further aspect, the active zone includes a non-magnetic wash arrangement that produces a stream of water or air to assist the dislodgement of the non-magnetisable material from the matrix.
[0029] In a further aspect, the matrix includes a continuous or discontinuous carriage structure supporting magnetisable elements.
[0030] In a further aspect, the carriage structure includes a housing, and the magnetisable elements include collection plates supported by the housing.
[0031] In a further aspect, the collection plates are vertically orientated and spaced apart from one another.
[0032] In a further aspect, the collection plates are vertically orientated or angled at an acute angle relative to the vertical, and are spaced apart from one another.
[0033] In a further aspect, the collection plates include a non-flat surface feature.
[0034] In a further aspect, the collection plates are corrugated.
[0035] In a further aspect, the housing is substantially non-magnetic.
[0036] In a further aspect, the unit further includes a yoke arranged to complete a magnetic circuit associated with the coil arrangement and the shield arrangement.
[0037] In a further aspect, the yoke is arranged to contact the shield arrangement to complete the magnetic circuit.
[0038] In a second main aspect, the present disclosure provides a system of magnetic separation units, the system including a plurality of magnetic separation units according to the first main aspect, with the matrix being configured to pass through each of the magnetic separation units.
[0039] In an aspect, at least some of the magnetic separation units are arranged side-by-side, in series, around a track, in a circular arrangement, or in a stacked arrangement.
[0040] In a third main aspect, the present disclosure provides a method of magnetic separation for a material having magnetic constituents and non-magnetic constituents, the method including creating a magnetic field with a coil in which the magnetic field generally extends in a direction of travel of a matrix adapted to receive the material, guiding the magnetic field with a shield arrangement so as to create a magnetic bypass of at least a portion of the matrix and thereby create a null zone and an active zone adjacent the null zone, at the active zone, magnetising the matrix by the magnetic field so that the magnetic constituents are attached to the matrix and non-magnetic constituents are passed, and at the null zone, relatively demagnetising the matrix by said magnetic bypass so that the magnetic constituents are detached from the matrix and passed.
[0041] In a fourth main aspect, the present disclosure provides a method of magnetic separation for a material having magnetic constituents and non-magnetic constituents, the method including, at an active zone, magnetising a portion of a matrix using a coil arrangement configured to generate a magnetic field generally in line with a direction of travel of the matrix, the magnetic constituents being attached to the portion of the matrix, and at a null zone adjacent the active zone, magnetically bypassing the portion of the matrix using a shield arrangement located between the coil arrangement and the portion of the matrix, the portion of the matrix being relatively demagnetised such that magnetic constituents are removable from the matrix.
[0042] In a fifth main aspect, the present disclosure provides a method of controlling a magnetic field generated by a coil arrangement for material separation of magnetic constituents and non-magnetic constituents, the method including locating a shield arrangement between the coil arrangement and a matrix adapted to travel in thedirection of the magnetic field such that the magnetic field within the shield arrangement is guided around the matrix to create a magnetic bypass of a portion of the matrix and thereby create a null zone in which the matrix is relatively demagnetised, allowing magnetic constituents attracted to the matrix in a prior active zone to be released in the null zone.
[0043] In a sixth main aspect, the present disclosure provides a magnetic separation unit for separating a material having magnetic constituents and non-magnetic constituents, including: a matrix adapted to receive the material; a passage through which the matrix may pass; a magnetic control arrangement associated with the passage; and, a coil arrangement having at least one coil arranged to extend at least partially around the passage to generate a magnetic field generally along the passage in a direction of travel of the matrix; wherein the coil arrangement and the magnetic control arrangement are configured to provide the unit with: an active zone, outside the magnetic control arrangement, in which a portion of the matrix is magnetisable so as to attract the magnetic constituents thereto; and, a null zone adjacent the active zone, in which the magnetic control arrangement provides a bypass for the magnetic field around the portion of the matrix such that the portion of the matrix becomes relatively demagnetised to allow release of the magnetic constituents.Brief Description of the Figures
[0044] The invention is described, by way of non-limiting example only, by reference to the accompanying figures, in which;
[0045] Figure 1 is a side perspective view illustrating a magnetic separation unit including three block arrangements;
[0046] Figure 2 is a part side perspective view illustrating the magnetic separation unit and indicating a path of the magnetic field;
[0047] Figure 3 is a side perspective view illustrating an example of a single block arrangement of the magnetic separation unit, the configuration and function of which is similar to that used in Figures 1 and 2;
[0048] Figure 4 is a top view illustrating the single block arrangement of the magnetic separation unit showing section A-A;
[0049] Figure 5 is a side view illustrating section A-A of the single block arrangement of the magnetic separation unit;
[0050] Figure 6 is a side view illustrating the single block arrangement of the magnetic separation unit showing section B-B and section C-C.
[0051] Figures 7a, 7b and 7c respectively illustrate a front view of the unit, section B-B of the unit and section C-C of the unit;
[0052] Figure 8 is a side perspective view illustrating the single block arrangement with the coil arrangement removed;
[0053] Figure 9 is a side perspective exploded parts view illustrating the single block arrangement with the coil arrangement removed;
[0054] Figure 10 is a perspective exploded parts view illustrating a housing of a material carriage of the magnetic separation unit;
[0055] Figure 11 is another perspective exploded parts view parts of the material carriage of the magnetic separation unit;
[0056] Figure 12 is a top view illustrating a housing of the material carriage of the magnetic separation unit;
[0057] Figure 13 is an end view illustrating the housing of the material carriage of the magnetic separation unit;
[0058] Figure 14 is a side perspective view illustrating a plurality of the magnetic separation units formed into a first example of a magnetic separation system;
[0059] Figure 15 is a side perspective view illustrating a plurality of the magnetic separation units formed into a second “stacked” example of a magnetic separation system;
[0060] Figure 16 is a side view illustrating a plurality of the magnetic separation units formed into the second “stacked” example of the magnetic separation system;
[0061] Figure 17 is a perspective view illustrating a second embodiment of a magnetic separation unit including a single block arrangement;
[0062] Figure 18 is a top sectional view illustrating the single block arrangement and the flow of the magnetic field;
[0063] Figure 19 is a perspective view illustrating a third embodiment of a magnetic separation unit including two block arrangements arranged with an oblong track;
[0064] Figure 20 is a perspective view illustrating a fourth embodiment of a magnetic separation unit including a plurality of block arrangements arranged with a longer oblong track;
[0065] Figure 21 is a perspective view illustrating a fifth embodiment of the magnetic separation unit including two block arrangements arranged with a track, with additional coils fitted to each unit block;
[0066] Figure 22 is a perspective view illustrating a sixth embodiment of the magnetic separation unit including a plurality of block arrangements arranged with a track, with additional coils fitted to each unit block, which is an extension of the fifth embodiment;
[0067] Figure 23 is a perspective view illustrating a seventh embodiment of the magnetic separation unit including a plurality of block arrangements arranged in a square track with rounded corners that have yokes fitted;
[0068] Figure 24 is a perspective view illustrating an eighth embodiment of the magnetic separation unit including a plurality of block arrangements arranged with a rectangular track with rounded corners that have yokes fitted, which is an extension of the seventh embodiment;
[0069] Figure 25 is a perspective view illustrating a ninth embodiment of the magnetic separation unit including two block arrangements arranged with a generally vertical oblong track;
[0070] Figure 26 is a perspective view illustrating a tenth embodiment of the magnetic separation unit including a plurality of block arrangements arranged with a generally vertical longer oblong track, which is an extension of the ninth embodiment;
[0071] Figure 27 is a perspective view illustrating an eleventh embodiment of the magnetic separation unit in which the plurality of core blocks are arranged with a circular track without yokes;
[0072] Figure 28 is a perspective view illustrating a twelfth embodiment of the magnetic separation unit in which the plurality of core blocks are arranged with a circular track with yokes;
[0073] Figure 29 is a perspective view illustrating a thirteenth embodiment of the magnetic separation unit having reciprocating matrices; and,
[0074] Figure 30 is a perspective view illustrating a fourteenth embodiment of the magnetic separation unit having parallel arranged matrices in the form of conveyors.Detailed DescriptionFirst embodiment
[0075] Referring to Figures 1 to 9, there is disclosed a magnetic separation unit or apparatus 10 for separating a material having magnetic constituents and non-magnetic or less magnetic constituents. Such a material may be, but not limited to, mineral sands that may including magnetic constituents such as ilmenite, magnetite, garnet, and monazite, and non-magnetic constituents such rutile and zircon. In other examples, it is contemplated the feed material could include, but not limited to, crushed coal or crushed iron ore.
[0076] In some examples, the magnetic separation unit 10 and associated system may also be applied in industries other than mineral processing. For example, the unit 10 may be used in recycling or waste processing applications, such as scrap metal recycling, to separate magnetic or relatively more magnetic metallic particles from a feed stream including shredded waste, comminuted scrap, construction and demolitionwaste, automotive shredder residue, electronic waste, or other mixed recyclable or discard material. In such embodiments, the feed material may include ferrous particles and other magnetically susceptible metallic constituents together with non-magnetic constituents such as plastics, glass, rubber, wood, fabric, soil, or other waste components, the unit 10 being operable to attract and retain the magnetic constituents in the active zone and to release those constituents in the null zone in the manner described above.
[0077] Referring initially to Figures 1 and 2, the unit 10 includes or receives a matrix 11 that is provided in the form of, but not limited to, a carriage arrangement 12 adapted to receive and convey the material, a passage 13 through which the carriage arrangement 12 may pass, a coil arrangement 14 having at least a first coil 15 adapted to generate a uniform magnetic field generally about the passage 13 and aligned with the direction of travel of the carriage arrangement 12, and a shield or field control arrangement 16 adapted to control or direct the magnetic field relative to the passage 13 and also enhance the magnetic field generated by the coil arrangement 14.
[0078] More specifically, the unit 10 is shown including three block arrangements 5 arranged in a linear or end to end fashion. Each block arrangement 5 of the unit 10 includes a hollow core block 7 which may comprise the shield or field control arrangement 16.
[0079] The hollow core block 7 may be formed of one or multiple parts. The hollow core block 7 includes or provides the shield or field control arrangement 16 which preferably includes magnetic field conductor elements 67 (shown in Figure 8) that may be provided in the form of, but not limited to, plates 69, as is further detailed below. Accordingly, the hollow core block 7 may be formed of one or more parts.
[0080] Conceptually, the magnetic field generated by the coils 15, 24 is boosted by the plates 69 of the core block 7, which are placed inside the coils 15, 24, while still allowing the passage 13 for the carriage arrangement 12 to pass through the coils 15, 24. These may in some forms be integrally formed or formed in parts, as shown in this embodiment.
[0081] A second function of each hollow core block 7, in addition to enhancing the magnetic field, is to divert the magnetic field away from its hollow centre being the passage 13. This then creates a zone of low magnetic field intensity inside each hollow core block 7. In effect, the core block 7 has a dual function, boosting the magnetic field generated by the coils 15, 24, and shielding its centre from the magnetic field.
[0082] As the carriage arrangement 12 passes through each hollow core block 7 of the block arrangement 5, it also passes through this region of low magnetic field intensity. The matrix will thus enter and exit a zone of low magnetic field intensity, referred to as the null zone 20, along its direction of motion.
[0083] The hollow core blocks 7 have a finite length and as the carriage arrangement 12 travels beyond the length of each core block 7, the magnetic field that was previously flowing in the hollow core block 7 is now forced to flow through the carriage arrangement 12. This creates a zone of high magnetic field intensity, referred to as the active zone 18, which the carriage arrangement 12 enters and exits.
[0084] The result is a magnetic field design where the null zone 20 and the active zone 18 are directly adjacent to each other. The carriage arrangement 12 travels into an active zone 18, followed directly by a null zone 20. The path of the magnetic field is illustrated in Figure 2 and indicated as “M”.
[0085] Referring now additionally to Figures 3 to 9, the coil arrangement 14 and shield arrangement 16 are configured to provide an active zone “A” generally followed by a null zone “N”. The null zone is generally intermediate the opposing ends 29 of the shield arrangement 16 of the hollow core block 7, with the active zone “A” immediately prior to the shield arrangement 16. As such, the carriage arrangement 12, more specifically the section or portion of the carriage arrangement 12 within the bounds of the shield arrangement 16, is shielded, which relatively demagnetises the section or portion of the carriage arrangement 12.
[0086] In the active zone, an activated portion 17 of the carriage arrangement 12 is outside of the hollow core block 7 and magnetisable by the magnetic field so as to attract the magnetic constituents, and in the null zone “N” the carriage arrangement 12is magnetically shielded so as to provide a null portion 19 which becomes relatively demagnetised to allow for the release of the magnetic constituents.
[0087] Each of the block arrangements 5 thereby provides a respective active zone and a respective null zone from which larger systems can be built or adapted as described below in relation to Figures 14 to 16.
[0088] In more detail, the at least one coil 15 extends generally around or wraps about the passage 13 and is provided with an electrically generated current to generate a magnetic field concentric to the at least one coil 15 and generally in a direction in line with and parallel to the passage 13 through which the carriage arrangement 12 passes. It is noted that whilst in this embodiment two coils 15, 24 are used for each block arrangement 5, in further examples below a single coil may also be used. Accordingly, embodiments in which a single coil is used for each block arrangement 5 are contemplated herein.
[0089] The shield arrangement 16 may include a body or shell 21 that is located between the least one coil 15 and the passage 13. The body or shell 21 may define the hollow core block 7 with the passage 13 therethrough. The coil 15 wraps or extends around the hollow core block 7 as best shown in Figure 5.
[0090] The body or shell 21 may be comprised of one or more of the field conductor elements 67 which may be the plates 69. The plates may be a metal with high magnetic permeability or at least higher high magnetic permeability relative to the passage 13 or carriage arrangement 12 therein. The body or shell 21 may pass partly or entirely around the passage 13.
[0091] Such magnetically permeable material could include solid steel plates 69 which form at least a first wall 30 and an opposing second wall 32 of the shield arrangement 16 with the passage 13 defined thereby. As such, the shield arrangement 16 may be thought of as a magnetic control arrangement or guide which bypasses the carriage arrangement 12 and ultimately shields the carriage arrangement 12 from the magnetic field and allows direction of the magnetic field.
[0092] It is noted that use of a material with higher magnetic permeability in the shield arrangement 16 enhances the magnetic field properties the coil arrangement 14 createswhich essentially turns the shield arrangement 16 and coil arrangement 14 into an electromagnet where the high magnetic permeability of the shield arrangement 16 focuses and boosts the magnetic field properties generated by the surrounding coil arrangement 14. The shield arrangement 16 of the hollow core block 7 thus performs two duties: to enhance the magnetic field properties generated by the coil arrangement 14 and shield the carriage arrangement 12 from the magnetic field to create the null zone.
[0093] Since the shield arrangement 16 has high magnetic permeability, the magnetic field preferentially travels through the shield arrangement 16 rather than the passage 13 or carriage arrangement 12 therein. This causes the carriage arrangement 12 within the shield arrangement 16 to become relatively demagnetised in the null zone.
[0094] A null zone separation feature 23 is placed at or proximate the null zone which may be a magnetic material separator 34 such as, but not limited to, a magnetic material wash arrangement 36 which is arranged to wash collected magnetic constituents from the null portion 19 of the carriage arrangement 12 as the magnetic field holding the magnetic constituents has been relatively weakened.
[0095] Prior to the shield arrangement 16, the generated magnetic field magnetises the activated portion 17 of the carriage arrangement 12 and provides the active zone in which magnetic constituents are preferentially attached to the active portion 17 of the carriage arrangement 12.
[0096] An active zone separation feature 25 is placed at or proximate the active zone which may be a non-magnetic material separator 38 such as, but not limited to, a nonmagnetic material wash arrangement 40 which is arranged to wash non-magnetic constituents from the active portion 17 of the carriage arrangement 12 as the magnetic field is holding the magnetic constituents to the active portion 17 of the carriage arrangement 12.
[0097] A material feed point 27 may be located just prior to or proximate to the active zone and more specifically prior to the active zone separation feature 25. The feed material contains the magnetic and non-magnetic constituents. Preferably, the material feed point 27 and the active zone separation feature 25 are immediately adjacent oneanother. The active zone separation feature 25 is located between and adjacent to the material feed point 27 and the shield arrangement 16.
[0098] In this first embodiment, the coil arrangement 14 includes the second coil 24 spaced apart from the first coil 15 with a gap 26 between the spaced apart coils 15, 24. It is noted that the coils 15 and 24 are spaced apart to allow room in the gap 26 for the null zone separation feature 23.
[0099] Each of the spaced coils 15, 24 includes respective first and second coil housings 35, 37 which each house one or more, and typically a plurality of coil wires 39 wrapped about the respective coil housings 35, 37. The plurality of coil wires 39 are connected to a power source (not shown) and control system (not shown) to provide the desired electro-magnetic field. The embodiments described herein may all utilise a similar electromagnetic coil arrangement with a power source and associated control system.Carriage Arrangement
[0100] Turning now to the carriage arrangement 12 in more detail and referring to Figures 8 to 11, the carriage arrangement 12 includes a continuous or discontinuous carriage structure or cartridge 42 supporting a plurality of magnetisable elements 44. Various forms of the carriage arrangement 12 are possible. However, in this example, the carriage structure 42 includes a housing 46 and a series of collection plates 48 mounted to the housing 46. Such plates 48 may be referred to as “salient plates”.
[0101] The collection plates 48 are preferably vertically oriented or could also be angled and spaced apart to define gaps 52 therebetween. The collection plates 48 may include non-flat surface features, such as corrugations, to enhance magnetic field gradients across the plate gaps and increase the effectiveness of magnetic particle capture.
[0102] The collection plates 48 are preferably formed from a material with high magnetic permeability that can handle the effects of an abrasive slurry flow or similar such as a magnetic stainless steel. However, the housing 46 is made preferably from a material with relatively less magnetic permeability such as a non-magnetic stainless steel. However, it is noted a non-metallic material could be used.
[0103] The housing 46 may include side walls 54 adapted to capture and retain the collection plates 48. The side walls 54 may include shaped slots 56 to receive and retain each of the collection plates 48 which extend between the side walls 54. One or both of the side walls 54 may support a drive part such as a rack or gear 57 which is driven by motor 60 shown below in Figures 14 to 16 and wheels 63 which engage and slide along the rails 62 shown in Figures 9, 15 and 16.System including First Embodiment
[0104] Referring now to Figures 14 to 16, magnetic separation unit 10 may be incorporated into a system 100 of magnetic separation units configured in various forms such as, but not limited to, a linear series, in a round circuit, parallel sets of units, or stacked. As may be appreciated from the Figures, the units 10 may be fitted in a compact arrangement which increases processing capacity in a smaller overall area. The system may be a single continuous system 102 as shown in Figure 14 or a stacked system 104 as shown in Figures 15 and 16.
[0105] In such a system, multiple magnetic separation units 10 are positioned along a path such that the carriage arrangement 12 sequentially or simultaneously passes through each unit 10. A motor 60 may be used to drive the carriage arrangement 12 and each carriage structure 42 may be movably coupled to adjacent ones of the carriage structures 42 in a chain to form the carriage arrangement 12. This allows, for example, a continuous loop to be formed by the carriage arrangement 12 sequentially.
[0106] This modular arrangement allows for staged magnetic separation, higher processing capacity, and increased throughput. Each unit may be independently controlled or operated in coordination to allow for optimised separation at different stages based on particle composition or magnetic susceptibility.
[0107] The carriage arrangement 12 may be driven along a guide rail 62 by a chain, rack and pinion system, or other mechanical or electromagnetic drive systems. Carriage structures 42 forming the carriage arrangement 12 may be removable from the guide rail 62, allowing for maintenance or replacement. Wash and collection systemsmay be integrated into each unit to remove and transport separated materials for downstream processing.Method of use including First Embodiment
[0108] Turning to method of use, a method of magnetic separation for a material having magnetic constituents and non-magnetic constituents may include the steps of:a. generating a magnetic field with at least one coil 15 in which at least part of the magnetic field is generally aligned with the direction of travel of a carriage arrangement 12 adapted to receive the material.b. providing an active zone 18 in which the magnetic field magnetises at least a portion of the carriage arrangement 12 to attract and retain magnetic constituents while allowing non-magnetic constituents to fall away or be washed off;c. providing a null zone 20 downstream of the active zone 18, in which the carriage arrangement 12 is magnetically shielded by a shield arrangement 16, thereby becoming relatively demagnetised to allow magnetic constituents to be released from the carriage arrangement 12, the shield arrangement 16 defining the length and position of the null zone and also functioning to boost the magnetic field;d. collecting the non-magnetic constituents via a non-magnetic wash arrangement 40 and collecting the released magnetic constituents via a magnetic wash arrangement 36, noting that the non-magnetic wash arrangement 40 and magnetic wash arrangement 36 may each comprise one or multiple parts; and,e. optionally repeating the steps of magnetisation and demagnetisation through additional active and null zones by passing the carriage arrangement 12 through successive magnetic separation units in a modular system.
[0109] This method allows for compact, efficient, continuous, and scalable separation of magnetically susceptible materials using alternating zones of magneticactivation and release, thereby enhancing recovery and throughput in processing applications. The further embodiments below are operated in a similar manner and the method of use is not again described.Second Embodiment
[0110] Referring now to Figures 17 and 18, there is shown a second embodiment of a magnetic separation unit 110. The second embodiment is a simplified implementation of the first embodiment and operates on the same underlying magnetic circuit principles. Accordingly, like sequences of numerals (i.e. 10, 110) are used, where appropriate, to denote like or corresponding parts.
[0111] Like the first embodiment, the magnetic separation unit 110 is adapted to separate a material having magnetic constituents and non-magnetic or less magnetic constituents. By way of example, the material may comprise mineral sands containing ilmenite, magnetite, garnet and monazite as magnetic constituents, and rutile and zircon as non-magnetic constituents. In other examples, the feed material may comprise crushed coal, crushed iron ore, tailings, recycled process streams, or other particulate or slurry feed materials containing constituents of differing magnetic susceptibility
[0112] In this embodiment, the magnetic separation unit 110 includes a single block arrangement 105 with a hollow core block 107, a matrix 111 which provides a carriage arrangement 112, a passage 113 through which the carriage arrangement 112 may pass, a coil arrangement 114 including a single coil 115, and one or more yokes 128 for closing the magnetic circuit. The hollow core block 107 provides a shield arrangement 116, also referred to herein as a magnetic control arrangement 116 or magnetic guide arrangement 116. The hollow core block 107 sits inside the coil 115 and defines the passage 113.
[0113] The coil 115 is arranged about the hollow core block 107 with a coil axis generally transverse to the direction of travel of the carriage arrangement 112, such that the hollow core block 107 is received within the interior of the coil 115 and the magnetic field is directed generally along the passage 113.
[0114] The shield arrangement 116 includes magnetic field conductor elements 167 in the form of plates 169 arranged so as to allow the passage 113 to extend through the core block 107. Accordingly, the core block 107 may not be a “block” per se, and may simply comprise one or more plates 169 formed of a material suitable to allow propagation of the magnetic field. The core block 107 may also take various shapes, such as being circular.
[0115] In this embodiment, the matrix 111 is itself the carriage arrangement 112, or provides the carriage arrangement 112, and is adapted to receive, support and transport feed material through the core block 107.
[0116] The second embodiment provides a simplified magnetic circuit relative to the first embodiment. In particular, instead of using a pair of spaced coils associated with a given core block, the embodiment of Figures 17 and 18 uses the single coil 115 arranged about the core block 107 and the passage 113, with the yoke or yokes 128 completing the magnetic circuit externally of the core block 107. This provides a mechanically simpler arrangement whilst maintaining the functional relationship between an active zone 118 and a null zone 120, as best indicated in Figure 18.
[0117] The coil 115 is arranged generally perpendicularly to the direction of travel of the matrix 111. When energised, the coil 115 generates a magnetic field which is guided by the magnetically permeable structure of the core block 107, including the shield arrangement 116, and returned through the yoke 128. The magnetic circuit is thereby established such that magnetic flux preferentially travels through the core block 107 and yoke 128 rather than through the passage 113.
[0118] The core block 107 accordingly performs a dual function. First, the core block 107 concentrates, boosts and directs the magnetic field generated by the single coil 115. Secondly, the shield arrangement 116, including the magnetic field conductor elements 167 in the form of plates 169, diverts or guides the magnetic field away from the hollow centre of the core block 107 defined by the passage 113 thus bypassing the passage 113 within the core block 107. In this way, the passage 113 and the portion of the carriage arrangement 112 passing therethrough are relatively magnetically shielded.
[0119] This shielding effect creates, within the core block 107, a region of relatively low magnetic field intensity defining a null zone 120. As the matrix 111 passes through the passage 113 and through the core block 107, the matrix 111 correspondingly passes through the null zone 120.
[0120] The core block 107 has a finite length in the direction of travel of the carriage arrangement 112. At locations beyond the extent of the core block 107, magnetic flux which had previously been guided preferentially through the core block 107 is forced to pass through the carriage arrangement 112 and matrix 111. This produces a region of relatively high magnetic field intensity in the active zone 118, immediately adjacent the null zone 120.
[0121] The result is a magnetic field configuration in which the active zone 118 and the null zone 120 are directly adjacent one another in the direction of travel of the matrix 111. Thus, in use, the carriage arrangement 112 passes into the active zone 118 and then directly into the null zone 120, thereby allowing magnetic capture to occur in the active zone 118 and magnetic release to occur in the null zone 120.
[0122] A feed point 127 may be located at or proximate the active zone 118. Feed material introduced at the feed point 127 is delivered onto or into the matrix 111 in the active zone 118. In the active zone 118, the magnetic field magnetises at least a portion of the matrix 111 and / or carriage arrangement 112 sufficiently to attract and retain magnetically susceptible particles. The matrix 111 then moves into the null zone 120.
[0123] A non-magnetic separator arrangement 125 may be located at or proximate the active zone 118. The non-magnetic separator arrangement 125 may include a non-magnetic material separator 138 and a non-magnetic wash arrangement 140 which discharges to a non-magnetic material outlet 172.
[0124] Non-magnetically susceptible particles are not materially retained by the magnetic field in the active zone 118 and may therefore pass through, fall from, or be washed from the matrix 111. The non-magnetic wash arrangement 140 may comprise a relatively gentle wash stream which assists release of the non-magnetic constituents whilst magnetic constituents remain magnetically retained on the matrix 111.
[0125] As the matrix 111 moves from the active zone 118 into the null zone 120, the magnetic holding force acting on retained magnetic constituents is reduced substantially due to the shielding effect produced by the core block 107, and in particular the shield arrangement 116 thereof, within the magnetic circuit. The retained magnetic constituents are thereby released from the matrix 111 in the null zone 120.
[0126] A null zone separator arrangement 123 may be located at or proximate the null zone 120. The null zone separator arrangement 123 includes a magnetic wash arrangement inlet 136, and a magnetic wash arrangement outlet 174. In some forms, the block arrangement 105 may include an internal chute, guide or discharge passage to direct released magnetic constituents from the matrix 111 into a magnetic collection region (not shown) therebelow. The magnetic wash is located inside the block and the bottom of the block forms a chute that transfers the now released magnetic particles towards a drain (not shown).
[0127] In the second embodiment, the matrix 111 is preferably a single component and may oscillate linearly along its length through the core block 107. By this oscillating movement, magnetic particles retained in the active zone 118 are conveyed into the null zone 120 and released therefrom, thereby separating the magnetic particles from the non-magnetic particles in a compact single-block arrangement.
[0128] The matrix 111 may comprise a magnetisable matrix having openings, apertures, ribs, corrugations, mesh, plates, slats or other particle receiving structures adapted to increase magnetic field gradients and particle capture area. The precise matrix structure may vary according to the material being treated and the desired separation characteristics.
[0129] In this embodiment, the single coil 115 and a yoke 128 provide a simplified magnetic circuit arrangement for the core block 107. The yoke 128 returns magnetic flux from one end region of the core block 107 to the other, thereby completing the magnetic loop externally of the matrix 111.
[0130] In the illustrated embodiment, the yoke 128 is shown arranged generally in a horizontal plane relative to the matrix 111. However, the yoke 128 may be disposedin another plane or orientation provided the magnetic circuit remains closed and the desired magnetic field path is maintained. The yoke 128 may be generally made of the same material as the shielding arrangement 116 which is a material with a relatively high magnetic permeability such as, but not limited to, steel.
[0131] The yoke 128 ensures the magnetic field generated by the coil 115 forms a loop. Thus, the field is generated by the coil 115, is boosted and guided by the shield arrangement 116 until it is forced to transition into the matrix 111 in the active zone 118. After the active zone 118, the magnetic field then transitions into the yoke 128 which allows it to reach the start of the magnetic loop again. The active zone 118 is generally located before the yoke 128 and the null zone 120 is generally located after the yoke 128.
[0132] Figure 18 illustrates, in sectional form, the path of the magnetic field through the second embodiment. As shown, magnetic flux is guided by the core block 107, including the shield arrangement 116 and its magnetic field conductor elements 167 in the form of plates 169, and is returned by the yoke 128 such that the passage 113 through the core block 107 defines the null zone 120, while the region immediately beyond the core block 107 defines the active zone 118 in which the magnetic field is forced through the matrix 111.
[0133] In Figure 18 it can be seen that the shield arrangement 116 which includes the magnetic field conductor elements 167 in the form of plates 169 functions to control, direct and enhance the magnetic field generated by the coil 115, and to divert or bypass that magnetic field around the passage 113 so as to establish the null zone 120 within the core block 107.Third Embodiment
[0134] Referring now to Figure 19, there is shown a third embodiment of a magnetic separation system 201. In this embodiment, the system 201 includes a plurality of magnetic separation units 210 arranged side-by-side, a matrix 211 providing a carriage arrangement 212, an oblong track 233, and one or more yokes 228 adapted to complete the magnetic circuit between adjacent block arrangements 205. Eachmagnetic separation unit 210 is associated with a respective block arrangement 205 including a hollow core block 207.
[0135] In the third embodiment, the matrix 211 preferably comprises a plurality of interlinked carriage structures or cartridges coupled together to form the carriage arrangement 212. The carriage arrangement 212 follows the oblong track 233 and travels substantially linearly through the two block arrangements 205 on opposed straight sections of the track 233.
[0136] Each block arrangement 205 may include a coil arrangement 214, at least one coil 215, and a shield or field control arrangement 216. The shield or field control arrangement 216 may include magnetic field conductor elements 267, such as core block plates 269, arranged to define a hollow core region through which the carriage arrangement 212 passes. Each block arrangement 205 thereby provides a respective active zone 218 and an adjacent null zone 220 functioning generally in the manner described in relation to the second embodiment.
[0137] The yokes 228 may be provided in the form of generally flat plates extending between end regions of the two block arrangements 205 so as to complete the magnetic flux path. This yoke arrangement is particularly suited to the side-by-side configuration and allows the oblong track 233 to be accommodated in a compact and mechanically practical layout.
[0138] In operation, the interlinked carriage structures of the matrix 211 circulate continuously around the oblong track 233. As the carriage arrangement 212 passes through each block arrangement 205, magnetic constituents may be captured in the respective active zone 218 and then released in the respective null zone 220. The use of two block arrangements 205 therefore provides a modular increase in capacity and / or a further stage of magnetic treatment relative to the second embodiment.
[0139] The two block arrangements 205 may be operated identically, or may be operated under different conditions. For example, while the matrix 211 may circulate around the oblong track 233 at a common speed through both block arrangements 205, the magnetic field intensity, wash flow, feed position, or other process conditionsassociated with each of the block arrangements 205 may differ so as to provide staged separation or upgrading.Fourth Embodiment
[0140] Referring now to Figure 20, there is shown a fourth embodiment of a magnetic separation system 301. The fourth embodiment may be regarded as an extension of the third embodiment. In this embodiment, the system 301 includes a plurality of magnetic separation units 310, a matrix 311 providing a carriage arrangement 312, and a longer oblong track 333 adapted to accommodate a greater number of block arrangements 305 along the straight sides of the track 333.
[0141] As in the third embodiment, the matrix 311 preferably comprises a plurality of interlinked carriage structures or cartridges. The carriage arrangement 312 circulates around the longer oblong track 333 and passes linearly through successive block arrangements 305 along the straight sections of the track 333.
[0142] Each block arrangement 305 may be substantially the same as the block arrangement 205 of the third embodiment and may include a coil arrangement 314, at least one coil 315, and a shield or field control arrangement 316 formed by magnetic field conductor elements 367, such as core block plates 369. Each block arrangement 305 thereby provides a respective active zone 318 and an adjacent null zone 320. The shield or field control arrangement 316 may be provided in the form of a hollow core block 307.
[0143] By increasing the number of block arrangements 305 arranged along the track 333, the fourth embodiment provides additional active / null stages. This may increase throughput, improve recovery, enhance cleaning efficiency, or permit staged separation of particles having different magnetic susceptibilities. The fourth embodiment is therefore particularly suited to higher capacity or more demanding industrial installations.
[0144] The longer oblong track 333 may be selected according to desired residence time, desired number of separation stages, throughput requirements,installation footprint, or other process design considerations. The modular nature of the arrangement also facilitates scaling by the addition or removal of block arrangements 305.Fifth Embodiment
[0145] Referring now to Figure 21, there is shown a fifth embodiment of a magnetic separation system 401. The fifth embodiment is generally similar to the third embodiment in that the system 401 includes a plurality of magnetic separation units 410 arranged side-by-side with a track 433 therebetween. However, in the fifth embodiment, each magnetic separation unit 410 is additionally provided with an extra coil 424.
[0146] The system 401 includes a matrix 411 providing a carriage arrangement 412, one or more yokes 428, and, for each magnetic separation unit 410, a respective block arrangement 405 having a primary coil arrangement 414 including at least one primary coil 415, together with the additional coil 424. The track 433 may be an oblong track and the matrix 411 may comprise a series of interlinked carriage structures moving around the track 433.
[0147] The additional coil 424 is preferably positioned on an opposite side of the active zone 418 relative to the primary coil 415. In this way, the magnetic field in the active zone 418 may be increased where a higher field strength, higher flux density, or stronger magnetic retention force is required.
[0148] Each block arrangement 405 nevertheless retains or includes a hollow core block 407 with a shield or field control arrangement 416 formed by magnetic field conductor elements 467, such as core block plates 469, so as to define a null zone 420 by diverting magnetic flux around the hollow centre through which the carriage arrangement 412 passes. Thus, the essential functional relationship of adjacent active and null zones is retained, but with increased capability for field intensification in the active zone 418.
[0149] The fifth embodiment may be advantageous where the feed contains relatively weakly magnetic particles, coarser particles, higher solids loading, or othermaterial requiring a stronger magnetic capture stage prior to entry into the null zone 420.Sixth Embodiment
[0150] Referring now to Figure 22, there is shown a sixth embodiment of a magnetic separation system 501. The sixth embodiment is an extension of the fifth embodiment and includes a plurality of magnetic separation units 510 arranged along a track 533, each magnetic separation unit 510 being associated with a respective block arrangement 505 provided with one or more additional coils 524.
[0151] A matrix 511 provides the carriage arrangement 512 and may again comprise interlinked carriage structures or cartridges circulating around the track 533. The track 533 may be an extended oblong track having opposed straight sections on which multiple block arrangements 505 are positioned.
[0152] Each block arrangement 505 includes a primary coil arrangement 514 having at least one primary coil 515, and a shield or field control arrangement 516 for providing an active zone 518 and an adjacent null zone 520. Again, the shield or field control arrangement 516 includes, or is provided in the form of, a hollow core block 507 within each block arrangement 505.
[0153] The additional coils 524 supplement the magnetic field generated in the active zone 518. A yoke 528 is provided at an end of the block arrangement 505 to complete the magnetic circuit and direct magnetic flux toward the next magnetic separation unit. The addition of the coils 524 does not alter the function of the yoke 528, although the yoke 528 may experience a higher internal magnetic field strength. The yoke 528 also ensures that the carriage arrangement 512 at the U-turn is outside of the magnetic circuit and is therefore not magnetically energised.
[0154] By combining a plurality of block arrangements 505 with the additional coils 524, the sixth embodiment provides both increased machine scale and increased magnetic field capability. This may permit higher throughput, staged magnetic upgrading, or treatment of feed materials requiring more aggressive magnetic capture conditions.Seventh Embodiment
[0155] Referring now to Figure 23, there is shown a seventh embodiment of a magnetic separation system 601. In this embodiment, the system 601 includes a plurality of magnetic separation units 610 arranged around a square track with rounded comers 633, and one or more yokes 628 are fitted to these comers so as to close the magnetic circuit around the track layout.
[0156] A matrix 611 may be provided in the form of a carriage arrangement 612 and preferably comprises a plurality of interlinked carriage structures following the square track with rounded corners 633. The straight sections of the track are preferably of sufficient length to accommodate the respective block arrangements 605.
[0157] Each block arrangement 605 includes a coil arrangement 614, at least one coil 615, and a shield or field control arrangement 616 thereby defining an active zone 618 and an adjacent null zone 620. The shield or field control arrangement 616 includes, or is provided in the form of, a hollow core block 607 within each block arrangement 605.
[0158] The yokes 628 may be located at comer or transition regions of the track 633 and may take the form of shaped yoke pieces suited to the geometry of the track. The yokes 628 transfer the magnetic field from one block arrangement 605 to the next, thereby ensuring that the carriages 612 in the comers are outside the magnetic circuit.
[0159] The seventh embodiment demonstrates that the track geometry need not be oblong for the invention to function effectively. Rather, other track geometries may be adopted, provided sufficient linear extent is available for the block arrangements 605 and the magnetic circuit is appropriately closed.Eighth Embodiment
[0160] Referring now to Figure 24, there is shown an eighth embodiment of a magnetic separation system 701. The eighth embodiment may be regarded as anextension of the seventh embodiment and includes a plurality of magnetic separation units 710, a matrix 711 providing a carriage arrangement 712, a square track with rounded comers 733, and one or more yokes 728.
[0161] Relative to the seventh embodiment, the square track with rounded comers 733 is elongated so as to accommodate more block arrangements 705 along one or both sides of the track 733. Each block arrangement 705 includes a coil arrangement 714, at least one coil 715, and a shield or field control arrangement 716 having magnetic field conductor elements 767, such as core block plates 769, for forming an active zone 718 and an adjacent null zone 720. The shield or field control arrangement 716 includes, or is provided in the form of, a hollow core block 707 within each block arrangement 705.
[0162] The matrix 711 circulates around the square track with rounded corners 733 and sequentially passes through the plurality of block arrangements 705. The elongated geometry provides an extended process path and increased machine capacity while retaining the modular active / null magnetic separation principles described above.Ninth Embodiment
[0163] Referring now to Figure 25, there is shown a ninth embodiment of a magnetic separation system 801. In this embodiment, the system 801 includes a plurality of magnetic separation units 810 arranged with a generally vertical oblong track 833. A matrix 811 provides a carriage arrangement 812 and travels around the track 833 in a generally vertical plane. One or more yokes 828 close the magnetic circuit between the block arrangements 805.
[0164] Each block arrangement 805 includes a coil arrangement 814, at least one coil 815, and a shield or field control arrangement 816 thereby providing an active zone 818 and an adjacent null zone 820. The matrix 811 preferably comprises interlinked carriage structures or cartridges. The shield or field control arrangement 816 includes, or is provided in the form of, a hollow core block 807 within each block arrangement 805.
[0165] An advantage of arranging the track 833 in a generally vertical plane is that the matrix 811 is inverted during a portion of its travel. That inversion may naturally assist in the release of oversized particles or particles unable to pass through the matrix 811. The ninth embodiment may therefore improve tolerance to oversize or tramp material in the feed.Tenth Embodiment
[0166] Referring now to Figure 26, there is shown a tenth embodiment of a magnetic separation system 901. The tenth embodiment is an extension of the ninth embodiment and includes a plurality of magnetic separation units 910 arranged with a generally vertical oblong track 933. A matrix 911 provides a carriage arrangement 912, and a yoke arrangement 928 closes the magnetic circuit.
[0167] Each block arrangement 905 includes a coil arrangement 914, at least one coil 915, and a shield or field control arrangement 916 so as to provide active zones 918 and adjacent null zones 920 at multiple locations around the track 933. The shield or field control arrangement 916 includes, or is provided in the form of, a hollow core block 907 within each block arrangement 905.
[0168] By extending the vertical track arrangement to include a plurality of block arrangements 905, the tenth embodiment increases processing capacity whilst retaining the inversion advantages described in relation to the ninth embodiment. The tenth embodiment may therefore be suited to compact vertically developed plant arrangements.Eleventh Embodiment
[0169] Referring now to Figure 27, there is shown an eleventh embodiment of a magnetic separation system 1001 in which a plurality of magnetic separation units 1010 are arranged in a circle without separate yokes. In this embodiment, a ring-shaped matrix 1011 provides a carriage arrangement 1012.
[0170] The matrix 1011 is preferably a single continuous ring-shaped component rather than a series of interlinked cartridges. A plurality of blockarrangements 1005 are positioned circumferentially around the matrix 1011. Each block arrangement 1005 may include a coil arrangement 1014, at least one coil 1015, and a shield or field control arrangement 1016 thereby defining active zones 1018 and adjacent null zones 1020 around the circumference. The shield or field control arrangement 1016 includes, or is provided in the form of, a hollow core block 1007 within each block arrangement 1005.
[0171] In this embodiment, separate yokes are not required because the circular arrangement of the block arrangements 1005 and associated magnetic circuit components itself completes the magnetic circuit. The ring-shaped matrix 1011 continuously passes through successive active and null zones as it rotates or indexes relative to the circumferentially arranged block arrangements 1005. A benefit of this embodiment is that the circular nature of the system is similar to the circular nature of older WHIMS separators, thereby making the replacement of such systems with this newer embodiment easier.Twelfth Embodiment
[0172] Referring now to Figure 28, there is shown a twelfth embodiment of a magnetic separation system 1101. The twelfth embodiment is generally similar to the eleventh embodiment, but includes one or more yoke pieces 1128 around the circular arrangement of magnetic separation units 1110. A ring-shaped matrix 1111 provides a carriage arrangement 1112.
[0173] In this embodiment, one or more positions otherwise occupied by block arrangements 1105 are instead occupied by yoke pieces 1128. The yoke pieces 1128 create a magnetic bypass region around the matrix 1111 and thereby provide locations at which substantially no magnetic field passes through the carriage arrangement 1112. Such locations may facilitate inspection, maintenance, cleaning, or replacement of the matrix 1111.
[0174] The remaining block arrangements 1105 each include a coil arrangement 1114, at least one coil 1115, and a shield or field control arrangement 1116 formed by magnetic field conductor elements 1167, such as core block plates 1169, thereby providing active zones 1118 and adjacent null zones 1120 at circumferentially spacedlocations. The shield or field control arrangement 1116 includes, or is provided in the form of, a hollow core block 1107 within each block arrangement 1105.
[0175] In addition to replicating the benefits of the previous embodiment, a benefit of including a yoke piece 1128 is easier access to the matrix 1111 to facilitate inspection, maintenance, cleaning, or replacement.Thirteenth Embodiment
[0176] Referring now to Figure 29, there is shown a thirteenth embodiment of a magnetic separation system 1201 having reciprocating matrices. In this embodiment, the system 1201 includes a plurality of magnetic separation units 1210 provided together with a plurality of matrices 1211 providing respective carriage arrangements 1212. The matrices 1211 are not necessarily interlinked with one another.
[0177] Each block arrangement 1205 may include a coil arrangement 1214, at least one coil 1215, and a shield or field control arrangement 1216 thereby defining an active zone 1218 and an adjacent null zone 1220. The shield or field control arrangement 1216 includes, or is provided in the form of, a hollow core block 1207 within each block arrangement 1205.
[0178] In this embodiment, the matrices 1211 may reciprocate through the block arrangements 1205, or may otherwise be advanced and withdrawn relative to the block arrangements 1205 in a non-continuous manner. A transfer system 1228, such as a conveyor, shuttle, pusher, or linear transfer mechanism, may transfer individual matrices 1211 from one block arrangement 1205 to the next. This allows discrete matrices 1211 to undergo magnetic capture and release operations without requiring an endless interlinked carriage arrangement.
[0179] The thirteenth embodiment may be advantageous where the use of discrete matrix modules provides benefits in maintenance, replacement, cleaning, or process flexibility. Different matrices 1211 may, if desired, be configured differently for different stages of treatment.Fourteenth embodiment
[0180] Referring now to Figure 30, there is shown a fourteenth embodiment of a magnetic separation system 1301 having parallel arranged matrices in the form of conveyors. In this embodiment, the system 1301 includes a plurality of magnetic separation units 1310, and the matrix 1311 is provided in the form of a plurality of conveyors 1312 which, in effect, provide a form of the carriage arrangement arranged generally in parallel.
[0181] Each block arrangement 1305 may include a coil arrangement 1314, at least one coil 1315, and a shield or field control arrangement 1316 thereby defining an active zone 1318 and an adj acent null zone 1320 for one or more of the conveyors 1311. A yoke 1328 is used to close the magnetic circuit. The shield or field control arrangement 1316 includes, or is provided in the form of, a hollow core block 1307 within each block arrangement 1305.
[0182] The conveyors 1311 are preferably perforated, apertured, or mesh-like such that non-magnetically susceptible particles may pass through the conveyors 1311 under gravity in the active zone 1318, whilst magnetically susceptible particles are retained on the conveyors 1311 under the influence of the magnetic field and then released in the null zone 1320. The conveyors 1311 may be arranged in stacked parallel relation to provide a relatively high-throughput machine architecture.
[0183] In the fourteenth embodiment, the use of multiple conveyors 1311 allows simultaneous treatment of multiple material streams or a larger overall material flow. The conveyor format may also simplify continuous feed and wash arrangements and may be particularly suited to larger industrial installations.General Statement Regarding Further Embodiments
[0184] In each of the embodiments described above, the coil arrangements and core block or field control arrangements may have a generally rectangular cross-section. However, other cross-sectional forms are also contemplated. By way of example, the coils and / or core blocks may have circular, oval, polygonal, or other suitable cross-sectional forms whilst still providing a magnetic circuit in which an active zone is positioned adjacent a null zone.
[0185] It will be appreciated from the foregoing that the concept underlying the later embodiments lies in the design of the magnetic circuit. In particular, the magnetic field is guided by relatively high permeability field conductor elements so as to create an active zone in which magnetic flux is forced through the matrix and an adjacent null zone in which the matrix is magnetically shielded by diversion or bypass of flux around the passage through which the matrix travels. This permits sequential magnetic capture and release of particles as the carriage arrangement moves through the respective block arrangements.Advantages of the Invention
[0186] In one advantage, the invention provides a magnetic circuit in which the magnetic field is arranged generally in line with the direction of travel of the matrix. A shield or field control arrangement, which may be a hollow core block, directs or bypasses the magnetic field around a selected passage region so as to create a null zone, including by creating a magnetic bypass of the portion of the matrix located in that region, whilst magnetic flux is forced through the matrix immediately beyond that region so as to create an active zone. This allows magnetic capture and magnetic release to occur sequentially along the travel path of the matrix.
[0187] In another advantage, the invention permits the null zone and the active zone to be positioned in close proximity to one another, and preferably directly adjacent one another, in the direction of travel of the matrix. This close active-zone / null-zone relationship enables a compact unit structure in which magnetic field intensification and magnetic shielding are integrated, thereby allowing efficient separation within a relatively short travel distance.
[0188] In another advantage, because the invention may be implemented as compact unit block arrangements, those block arrangements may be configured in a range of machine layouts, including side-by-side, in series, around oblong or circular tracks, in vertical arrangements, or with reciprocating or conveyor-type matrices. The invention therefore provides a magnetic separation architecture that is compact, modular and readily scalable while retaining the same underlying magnetic field control principle.
[0189] Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.
[0190] The reference in this specification to any known matter or any prior publication is not, and should not be taken to be, an acknowledgment or admission or suggestion that the known matter or prior art publication forms part of the common general knowledge in the field to which this specification relates.
[0191] While specific examples of the invention have been described, it will be understood that the invention extends to alternative combinations of the features disclosed or evident from the disclosure provided herein.
[0192] Many and various modifications will be apparent to those skilled in the art without departing from the scope of the invention disclosed or evident from the disclosure provided herein.
Claims
The claims defining the Invention are as follows:
1. A magnetic separation unit for separating a material having magnetic constituents and non-magnetic constituents, including:a matrix adapted to receive the material;a shield arrangement associated with a passage through which the matrix may pass; and,a coil arrangement having at least one coil arranged to extend at least partially around the shield arrangement to generate a magnetic field generally along the passage in a direction of travel of the matrix;wherein the coil arrangement and the shield arrangement are configured to provide the unit with:an active zone, outside the shield arrangement, in which a portion of the matrix is magnetisable so as to attract the magnetic constituents thereto; and, a null zone adjacent the active zone, in which the portion of the matrix is magnetically shielded by the shield arrangement, the shield arrangement creating a bypass for the magnetic field around the portion of the matrix such that the portion of the matrix becomes relatively demagnetised to allow release of the magnetic constituents.
2. The magnetic separation unit according to claim 1, wherein the matrix is provided in the form of a carriage arrangement adapted to receive and transport the material.
3. The magnetic separation unit according to claim 1 or claim 2, wherein the at least one coil extends around the shield arrangement.
4. The magnetic separation unit according to any one of the preceding claims, wherein the at least one coil is arranged generally perpendicularly to a direction of travel of the matrix.
5. The magnetic separation unit according to any one of the preceding claims, wherein the magnetic field is generated generally in line with a direction of travel of the matrix.
6. The magnetic separation unit according to any one of the preceding claims, wherein the null zone is at least partially defined within the shield arrangement.
7. The magnetic separation unit according to any one of the preceding claims, wherein the active zone is located immediately adjacent and outside the shield arrangement.
8. The magnetic separation unit according to any one of the preceding claims, wherein the shield arrangement includes spaced apart walls between which the matrix passes so as to define the passage.
9. The magnetic separation unit according to claim 8, wherein the walls are formed of a magnetisable material so as to preferentially direct the magnetic field around the portion of the matrix in the null zone.
10. The magnetic separation unit according to any one of the preceding claims, wherein the shield arrangement is arranged to enhance the magnetic field in the direction of travel of the matrix.
11. The magnetic separation unit according to any one of the preceding claims, wherein the coil arrangement includes two or more spaced apart coils with a gap therebetween.
12. The magnetic separation unit according to claim 11, wherein the shield arrangement bridges the gap and extends between the two or more spaced apart coils.
13. The magnetic separation unit according to any one of the preceding claims, wherein the unit includes a magnetic material collector located at or proximate the null zone.
14. The magnetic separation unit according to any one of the preceding claims, wherein the unit includes a magnetic wash arrangement located at or proximate the null zone.
15. The magnetic separation unit according to any one of the preceding claims, wherein the unit includes a non-magnetic material collector located at or proximate the active zone.
16. The magnetic separation unit according to claim 15, wherein the non-magnetic material collector is located immediately prior to the shield arrangement.
17. The magnetic separation unit according to claim 15 or claim 16, wherein the unit includes a non-magnetic wash arrangement located at or proximate the active zone.
18. The magnetic separation unit according to any one of the preceding claims, wherein the matrix includes a continuous or discontinuous carriage structure supporting magnetisable elements.
19. The magnetic separation unit according to claim 18, wherein the carriage structure includes a housing, and the magnetisable elements include collection plates supported by the housing.
20. The magnetic separation unit according to claim 19, wherein the collection plates are vertically or near vertically orientated and spaced apart from one another.
21. The magnetic separation unit according to claim 19 or claim 20, wherein the collection plates include a non-flat surface feature.
22. The magnetic separation unit according to claim 21, wherein the collection plates are corrugated.
23. The magnetic separation unit according to any one of claims 19 to 22, wherein the housing is substantially non-magnetic.
24. The magnetic separation unit according to any one of the preceding claims, further including a yoke arranged to complete a magnetic circuit associated with the coil arrangement and the shield arrangement.
25. The magnetic separation unit according to claim 24, wherein the yoke is arranged to contact the shield arrangement to complete the magnetic circuit.
26. A system of magnetic separation units, the system including a plurality of the magnetic separation units according to any one of claims 1 to 25, with the matrix being configured to pass through each of the magnetic separation units27. The system according to claim 26, wherein at least some of the magnetic separation units are arranged side-by-side, in series, around a track, in a circular arrangement, or in a stacked arrangement.
28. A method of magnetic separation for a material having magnetic constituents and non-magnetic constituents, the method including:creating a magnetic field with a coil in which the magnetic field generally extends in a direction of travel of a matrix adapted to receive the material;guiding the magnetic field with a shield arrangement so as to create a magnetic bypass of at least a portion of the matrix and thereby create a null zone and an active zone adjacent the null zone;at the active zone, magnetising the matrix by the magnetic field so that the magnetic constituents are attached to the matrix and non-magnetic constituents are passed; and,at the null zone, relatively demagnetising the matrix by said magnetic bypass so that the magnetic constituents are detached from the matrix and passed.
29. A method of magnetic separation for a material having magnetic constituents and non-magnetic constituents, the method including:at an active zone, magnetising a portion of a matrix using a coil arrangement configured to generate a magnetic field generally in line with a direction of travel of the matrix, the magnetic constituents being attached to the portion of the matrix; and at a null zone, adjacent the active zone, magnetically bypassing the portion of the matrix using a shield arrangement located between the coil arrangement and the portion of the matrix, the portion of the matrix being relatively demagnetised such that magnetic constituents are removable from the matrix.
30. A method of controlling a magnetic field generated by a coil arrangement for material separation of magnetic constituents and non-magnetic constituents, the method including locating a shield arrangement between the coil arrangement and a matrix adapted to travel in the direction of the magnetic field such that the magnetic field within the shield arrangement is guided around the matrix to create a magnetic bypass of a portion of the matrix and thereby create a null zone in which the matrix is relatively demagnetised, allowing magnetic constituents attracted to the matrix in a prior active zone to be released in the null zone.
31. A magnetic separation unit for separating a material having magnetic constituents and non-magnetic constituents, including:a matrix adapted to receive the material;a passage through which the matrix may pass;a magnetic control arrangement associated with the passage; and, a coil arrangement having at least one coil arranged to extend at least partially around the passage to generate a magnetic field generally along the passage in a direction of travel of the matrix;wherein the coil arrangement and the magnetic control arrangement are configured to provide the unit with:an active zone, outside the magnetic control arrangement, in which a portion of the matrix is magnetisable so as to attract the magnetic constituents thereto; and,a null zone adjacent the active zone, in which the magnetic control arrangement provides a bypass for the magnetic field around the portion of the matrix such that the portion of the matrix becomes relatively demagnetised to allow release of the magnetic constituents.