WO2015183806A1

WO2015183806A1 - Disperser for self-aspirated flotation cells

Info

Publication number: WO2015183806A1
Application number: PCT/US2015/032423
Authority: WO
Inventors: Keri CALDWELL; Timothy J. Olson; Yihong Yang
Original assignee: Flsmidth A/S
Priority date: 2014-05-27
Filing date: 2015-05-26
Publication date: 2015-12-03
Also published as: CL2016002990A1

Abstract

Disclosed, is a retrofittable disperser apparatus [10] for a self-aspirated flotation cell. The retrofittable disperser apparatus [10] comprises a disperser assembly having a tubular portion [16C], a number of orifices [12] extending through the tubular portion [16C], and a number of blades [16A] extending radially-inwardly from the tubular portion [16C]. Also disclosed, is a self-aspirated flotation cell comprising a retrofittable disperser apparatus [10] and a method of flotation utilizing a retrofittable disperser apparatus [10] within a self-aspirated flotation cell.

Description

DISPERSER FOR SELF-ASPIRATED FLOTATION CELLS

Inventors: Keri Caldwell

Timothy J. Olson

Yihong Yang

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the following priority documents: U.S. Provisional Patent Application Serial No. 62/003,438 filed on 27 May 2014, titled "DISPERSER FOR SELF-ASPIRATED FLOTATION CELLS", and U.S. Provisional Patent Application Serial No. 62/111,382 filed on 3 Feb 2015, titled "DISPERSER FOR SELF- AS PIRATED FLOTATION CELLS". These documents are hereby incorporated by reference in their entirety for any and/or all purposes set forth herein.

FIELD OF THE INVENTION

This invention relates to flotation cells, and more particularly to disperser apparatus for self-aspirated flotation machines which are used to diffuse energy of slurry or pulp adjacent a rotor, and form bubbles for particle attachment.

BACKGROUND OF THE INVENTION

The current FLSmidth® Wemco® self-aspirated flotation machines have a rotor, a disperser surrounding the rotor, and a hood located above the disperser, in order to suspend particles, ingest air, and provide means for bubble-particle contact. As shown in FIGS. 1-3, various designs for dispersers have been used in the past. FIG. 1 shows a disperser 910 with half bars 914 secured thereto. A plurality of orifices 912 are provided within a tubular portion; however, no orifices are provided to the half bars 914. A rotor 900 is provided therein, and there is an extremely large clearance between the half bars 914 and the rotor 900 blades. FIG. 2 shows a disperser 1910 having a tubular portion with a plurality of orifices 1912 disposed therein. FIG. 3 suggests a disperser 2910 having a tubular portion having a plurality of orifices 2912 therein, a rotor 2900 disposed within the disperser 2910, and a frustoconical hood 2920 located above the disperser 2910 and rotor 2900.

It is desired to provide an improved disperser apparatus for flotation cells which overcomes problems associated with conventional dispersers, and improves overall recovery performance of self-aspirated flotation machines.

OBJECTS OF THE INVENTION

It is, therefore, an object of some embodiments of the invention to provide a robust disperser apparatus for flotation cells which overcomes problems seen with conventional disperser apparatus.

It is also an object of some embodiments of the invention to increase recovery in self- aspirated flotation cells while maintaining the ability to keep particles in suspension and ingest air.

It is further an object of some embodiments of the invention to provide a disperser apparatus which may advantageously incorporate a series of blades which may have radially- extending elongated slots for improved bubble sizing.

Moreover, it is an object of some embodiments of the invention to facilitate

manufacturing of a disperser for use in a self-aspirated flotation cell. Yet other objects of some embodiments of the invention include providing a disperser apparatus which exhibits a significantly improved ease of manufacture and installation.

It is yet another object of some embodiments of the invention to increase recovery by changing/altering the suspension of particles within the flotation cell, the air ingested by the cell, and/or the attachment between the particles and bubbles.

Another object of some embodiments of the invention is to go "better" rather than "bigger" in flotation cell design, i.e., to focus on mineral recovery efficiency rather than sizing.

It is yet another object of some embodiments of the invention to provide a retrofittable solution which may allow a customer to replace an existing disperser.

It is also an object of some embodiments of the invention to provide a better-performing disperser design in at least the sense of mineral recovery.

These and other objects of the invention will be apparent from the drawings and description herein. Although every object of the invention is believed to be attained by at least one embodiment of the invention, there is not necessarily any one embodiment of the invention that achieves all of the objects of the invention. While certain embodiments shown may not necessarily be cheaper to manufacture and/or operate than those shown in FIGS. 1-3, test work has revealed that overall recovery may be improved with the proposed designs disclosed herein, and this improved recovery may advantageously offset any increased costs that might be incurred with the proposed inventive designs.

SUMMARY OF THE INVENTION

A retrofittable disperser apparatus for a self- aspirated flotation cell is disclosed. The retrofittable disperser apparatus may comprise a disperser assembly having a tubular portion, a number of orifices extending through the tubular portion, and a number of blades extending radially- inwardly from the tubular portion. At least one of said number of blades extending radially- inwardly from the tubular portion may comprise a number of blade apertures. The number of blade apertures may comprise a number of elongated slots each having an axial length which is less than a radial length. The number of blade apertures may be arranged so as to be in axial alignment with each other at a similar radial location. However, in some embodiments, the number of blade apertures may be arranged so as to be staggered with at least two blade apertures sharing different radial locations. The number of blade apertures may comprise a number of rectangular- shaped or oval shaped blade apertures.

In some embodiments, the retrofittable disperser apparatus may further comprise a mounting ring for securing a hood thereto. In some embodiments, the retrofittable disperser apparatus may further comprise a radially-extending shelf extending between the mounting ring and the tubular portion. In some embodiments, the mounting ring may further comprise one or more mounting bosses. In some embodiments, the mounting ring may further comprise a first set of holes. In some embodiments, the tubular portion may further comprise a second set of holes. In some embodiments, said number of orifices may comprise one or more outer chamfers or one or more inner chamfers. In some embodiments, said number blades extending radially- inwardly from the tubular portion may comprise blades having a blade axial length, a blade radial width, and a blade circumferential thickness. In some embodiments, said blade axial length may be greater than said blade radial width and blade circumferential thickness. In some embodiments, said blade radial width may be greater than said blade circumferential thickness. In some embodiments, said number of blade apertures may be at least as long in a radial direction as said circumferential thickness. In some embodiments, said number of blades may be modular in nature and may be configured to be attached to the tubular portion via a number of blade fasteners. In some embodiments, said tubular portion may be modular and comprised of a number of segmented tubular portion segments. The number of segmented tubular portion segments may be configured to be attached to each other. In some embodiments, said segmented tubular portion segments may comprise at least one flange. In some embodiments, each segmented tubular portion segment may comprise two flanges. Each flange may comprise a number of flange fastener clearance holes for receiving a respective number of blade fasteners, or for welding together. Adjacent segmented tubular portion segments may be connected by virtue of said blade fasteners or welds.

A self-aspirated flotation cell is also disclosed. The self-aspirated flotation cell comprises a retrofittable disperser apparatus. The retrofittable disperser apparatus may comprise a disperser assembly having a tubular portion, a number of orifices extending through the tubular portion, and a number of blades extending radially-inwardly from the tubular portion.

A method of flotation is also disclosed. The method comprises providing a retrofittable disperser apparatus to a self-aspirated flotation cell, the retrofittable disperser apparatus comprising: a disperser assembly having a tubular portion, a number of orifices extending through the tubular portion, and a number of blades extending radially-inwardly from the tubular portion. The method may comprise the steps of providing a rotor within said retrofittable disperser apparatus; providing slurry containing mineral, gangue, and a reagent to the self- aspirated flotation cell; and, floating the mineral from the gangue by virtue of rotating the rotor. During operation, shear to the slurry may be substantially increased and/or bubble size controlled, thereby substantially increasing recovery. A retrofittable disperser apparatus [70] for a self-aspirated flotation cell comprising: a disperser assembly having a lower shelf [75'], a number of orifices [72'] extending through the lower shelf [75'] is further disclosed. According to some embodiments, the retrofittable disperser apparatus [70] may comprise a number of blades [76A] extending radially-inwardly; wherein the number of blades [76A] may extend upwards from the lower shelf [75'].

It will be appreciated from this disclosure, and the drawings, that various

features/components and method steps described herein may be altered without significantly departing from the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

To complement the description which is being made, and for the purpose of aiding to better understand the features of the invention, a set of drawings illustrating preferred sample preparation apparatus and methods of using the same is attached to the present specification as an integral part thereof, in which the following has been depicted with an illustrative and non- limiting character. It should be understood that like reference numbers used in the drawings may identify like components.

FIGS 1-3 suggest various types of conventional dispersers known in the art;

FIGS. 4 and 5 suggest a disperser according to some embodiments;

FIGS. 6 and 7 suggest a disperser according to some embodiments;

FIG. 8 suggests a disperser according to some embodiments comprising narrow width removable blades and/or an ability to easily disassemble the disperser; FIG. 9 suggests a disperser according to some embodiments comprising wider removable blades and/or an ability to easily disassemble the disperser, wherein the removable blades comprise a number of aligned radially-elongated openings;

FIG. 10 suggests a disperser according to some embodiments comprising yet even wider removable blades and/or an ability to easily disassemble the disperser, wherein the removable blades comprise a number of staggered radially-elongated openings;

FIG. 11 suggests one part of a multi-part disperser shell;

FIG. 12 suggests a narrow width removable blade shown in FIG. 8, according to some embodiments;

FIG. 13 suggests a wider removable blade shown in FIG. 9, according to some embodiments;

FIG. 14 suggests an even wider removable blade shown in FIG. 10, according to some embodiments; and

FIGS. 15 and 16 suggest a disperser according to some embodiments comprising a lower shelf having orifices (e.g., apertures, openings) extending therethrough, wherein blades may be welded to the shelves to form fastening welds as blade fasteners; and wherein no tubular portion may be provided.

FIGS. 17-22 suggest a disperser and components thereof, according to some

embodiments, comprising a framework surrounded by a tubular portion; wherein the framework surrounded by a tubular portion may be subsequently covered in a resistant material, such as a urethane material, without limitation.

FIGS. 23a-23b suggest a disperser and components thereof, according to some embodiments comprising a lower shelf which may be provided as a ring, and an upper shelf; wherein wide blades may be welded or fastened to the lower and/or upper shelves; and wherein a tubular portion may be provided, or may not be provided (as shown).

FIGS. 24a-24b suggest a disperser which is similar to the embodiment shown in FIGS. 23a-23b; however, which may be provided with narrower blades and/or with fewer orifices provided through the blades, without limitation.

In the following, the invention will be described in more detail with reference to

drawings in conjunction with exemplary embodiments.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention described herein and shown in the

accompanying figures have shown, at a laboratory scale, to increase flotation recovery and stabilize the vortex in the Wemco® standpipe. The new disperser designs found in FIGS. 4-14 were shown to increase recovery with a series of different rotor and hood combinations. Further investigation revealed that as the shear rate of the disperser was incrementally increased, recovery also increased. This discovery was backed up by computational fluid dynamic (CFD) modeling, which confirmed that by increasing shear, turbulence dissipation increased as well as particle attachment.

FIGS. 4 and 5 show a disperser 10 according to some embodiments. The disperser 10 comprises a mounting ring 11 having a number of mounting bosses 17, a first set of holes 18 through said number of mounting bosses 17, for mounting a hood (not shown) and/or for mounting the disperser 10 to a self-aspirating flotation cell (not shown). A second set of holes 19 may further be provided for further securement of a hood, other ancilliary feature, and/or to connect the disperser 10 to a self-aspirating flotation cell (not shown). The mounting ring 11 may comprise a radially-inwardly extending shelf 15 at a bottom portion thereof, which joins a axially-extending tubular portion 16C. The tubular portion 16C may comprise a number of orifices 12, such as round orifices 12 as shown, or non-round (e.g., square or slotted) orifices (not shown). Alternatively, orifices 12 may comprise elongated orifices, which may be axially (as depicted in FIGS. 8-11), or circumferentially-elongated (not shown). In some embodiments, one or more of the orifices 12 may comprise inner chamfers 14 on inside edge surfaces of the tubular portion 16C. In some embodiments, one or more of the orifices 12 may comprise outer chamfers 13 on outside edge surfaces of the tubular portion 16C. Extending radially-inwardly from an inside surface of the tubular portion 16C are a number of blades 16A having a blade axial length T, a blade

circumferential thickness 't', and a blade radial width 'w'. While blades 16A are shown to be rectangular prisms, one or more of the blades may comprise a taper or curved surface in any one or more of these directions to form various cross-sectional polygons or curved shapes.

One or more of the blades 16A may comprise one or more blade apertures 16B having a blade aperture axial length 'a' and a blade aperture radial length 'b'. In some instances, 'a' may be equal to 'b' or not equal to 'b' (as shown). In other words, the one or more blade apertures 16B may be elongated as shown, and may be represented as a radially-elongated slot, for example, wherein blade aperture radial length 'b' is greater than blade aperture axial length 'a'. Blades 16A may be positioned relative to the tubular portion 16C such that there is a blade axial offset 'd' from shelf 15 as shown. Blades 16A may be positioned relative to each other circumferentially around tubular portion 16C, and spaced from each other by a circumferential blade spacing 'c'. It should be understood that although disperser 10 is shown with even blade 16A spacing with consistent circumferential blade spacings 'c', circumferential blade spacings 'c' may vary about the

circumference of tubular portion 16C. FIGS. 6 and 7 show a disperser 20 according to some embodiments. The disperser 20 comprises a mounting ring 21 having a number of mounting bosses 27, a first set of holes 28 through said number of mounting bosses 27, for mounting a hood (not shown) and/or for mounting the disperser 20 to a self-aspirating flotation cell (not shown). A second set of holes 29 may further be provided for further securement of a hood, other ancilliary feature, and/or to connect the disperser 20 to a self-aspirating flotation cell (not shown). The mounting ring 21 may comprise a radially-inwardly extending shelf 25 at a bottom portion thereof, which joins an axially-extending tubular portion 26C. The tubular portion 26C may comprise a number of orifices 22, such as round orifices 22 as shown, or non-round (e.g., square or slotted) orifices (not shown). Alternatively, orifices 22 may comprise elongated orifices, which may be axially or circumferentially-elongated (not shown). In some embodiments, one or more of the orifices 22 may comprise inner chamfers 24 on inside edge surfaces of the tubular portion 26C. In some embodiments, one or more of the orifices 22 may comprise outer chamfers 23 on outside edge surfaces of the tubular portion 26C. Extending radially-inwardly from an inside surface of the tubular portion 26C are a number of blades 26A having a blade axial length T, a blade circumferential thickness 't', and a blade radial width 'w'. One or more of the blades 26 A may comprise one or more blade apertures 26B having a blade aperture axial length 'a' and a blade aperture radial length 'b'. In some instances, 'a' may be equal to 'b' or not equal to 'b' (as shown). In other words, the one or more blade apertures 26B may be elongated as shown, and may be represented as a radially-elongated slot, wherein blade aperture radial length 'b' is greater than blade aperture axial length 'a'. Blades 26A may be positioned relative to the tubular portion 26C such that there is a blade axial offset 'd' from shelf 25 as shown. Blades 26A may be positioned relative to each other circumferentially around tubular portion 26C, and spaced from each other by a circumferential blade spacing 'c'. FIG. 8 suggests a disperser 30 according to some embodiments, wherein one or more blades 36A are removably attached to a segmented tubular portion 36C via a number of blade fasteners 36F. The blades 36A are circumferentially-spaced by a circumferential blade spacing 'c', and extend radially-inwardly for a blade radial width 'w'. Each blade 36A comprises a blade axial length T and a blade circumferential thickness 't'. Blades 36A may be axially offset by a blade axial offset 'd' from an upper portion, surface, or edge of the segmented tubular portion 36C. The segmented tubular portion 36C may comprise a plurality of orifices 32, which may be circular (as shown in FIGS. 4-7), or non-circular, and which may have an orifice width 'χ' which is less than an orifice height 'y'. A second set of holes 39 may be provided for attachment of a mounting a hood (not shown) or securing the disperser 30 within a flotation cell. Each segment of the segmented tubular portion 36C may comprise one or more flanges 36D which are configured to abut respective adjacent flanges 36D. One or more flanges 36D may comprise flange fasteners 36E to secure adjacent adjoining segmented tubular portion 36C segments.

FIG. 9 suggests a disperser 40 according to some embodiments, wherein one or more blades 46A are removably attached to a segmented tubular portion 46C via a number of blade fasteners 46F. The blades 46A are preferably circumferentially-spaced by a uniform

circumferential blade spacing 'c', and extend radially-inwardly for a blade radial width 'w'. Each blade 46A comprises a blade axial length T and a blade circumferential thickness 't'. Blades 46A may also comprise one or more blade apertures 46B, such as radially-elongated slots as shown. In some preferred embodiments, the one or more blade apertures 46B are larger in a radially-extending direction than an axially-extending direction as shown. Also as shown, in some embodiments, the one or more blade apertures 46B may be aligned (e.g., so as to share a common radial location as shown). Blades 46A may be axially offset by a blade axial offset 'd' from an upper portion, surface, or edge of the segmented tubular portion 46C. In some non-illustrated embodiments, the blade axial offset 'd' may differ for different blades 46A, wherein blades are axially staggered, or are intermittently longer or shorter than one or more adjacent blades. The segmented tubular portion 46C may comprise a plurality of orifices 42, which may be circular, or non-circular, and which may have an orifice width Y which is less than an orifice height 'y' (as shown). A second set of holes 49 may be provided for attachment of a mounting a hood (not shown) or securing the disperser 40 within a flotation cell. Each segment of the segmented tubular portion 46C may comprise one or more flanges 46D which are configured to abut respective adjacent flanges 46D. One or more flanges 46D may comprise flange fasteners 46E to secure adjacent adjoining segmented tubular portion 46C segments.

FIG. 10 suggests a disperser 50 according to some embodiments, wherein one or more blades 56A are removably attached to a segmented tubular portion 56C via a number of blade fasteners 56F. The blades 56A are circumferentially-spaced by a circumferential blade spacing 'c', and extend radially-inwardly for a blade radial width 'w'. Each blade 56A comprises a blade axial length T and a blade circumferential thickness 't'. Blades 56A may also comprise one or more blade apertures 56B, such as radially-elongated slots as shown. In some preferred embodiments, the one or more blade apertures 56B are larger in a radially-extending direction than an axially-extending direction as shown. Also as shown, in some embodiments, the one or more blade apertures 56B may be staggered, spaced, or 'zig-zagged' (e.g., so as to be located at different radial and/or axial locations as shown). Blades 56A may be axially offset by a blade axial offset 'd' from an upper portion, surface, or edge of the segmented tubular portion 56C. The segmented tubular portion 56C may comprise a plurality of orifices 52, which may be circular, or non-circular, and which may have an orifice width Y which is less than an orifice height 'y' (as shown). A second set of holes 59 may be provided for attachment of a mounting a hood (not shown) or securing the disperser 50 within a flotation cell. Each segment of the segmented tubular portion 56C may comprise one or more flanges 56D which are configured to abut respective adjacent flanges 56D. One or more flanges 56D may comprise flange fasteners 56E to secure adjacent adjoining segmented tubular portion 56C segments.

FIG. 11 shows a segmented tubular portion segment 66C which may form a portion of a segmented tubular portion 36C, 46C, 56C. The segmented tubular portion segment 66C may comprise a plurality of orifices 62 therein, each orifice having an orifice width Y and orifice height 'y'. In some embodiments, Y may be greater than 'y'. In some embodiments, Y may be equal to 'y'. In some embodiments, Y may be less than 'y'. Orifices 62 may be circular, or non-circular shapes (e.g., square, ovals, rectangles, triangles, polygons, irregular shapes, or the like). A second set of holes 69 may be provided for various attachment purposes. For example, without limitation, the second set of holes 69 may be used to attach the disperser 30, 40, 50 to the flotation tank, or may be used to attach a hood (not shown) to the disperser 30, 40, 50. One or more flanges 66D may be provided to the segmented tubular portion segment 66C, for example at one or more distal arcuate ends, for easy assembly and disassembly with adjoining adjacent segmented tubular portion segments 66C. The segmented tubular portion segment 66C may comprise a plurality of blade fastener clearance holes 66G to accommodate blade fasteners 36F, 46F, 56F for attaching blades 36A, 46A, 56A to the segmented tubular portion segment 66C. Flange fastener clearance holes 66H may be provided to flanges 66D to accommodate flange fasteners 36E, 46E, 56E. Flanges may, in some embodiments, be welded together rather than bolted together.

FIGS. 12-14 are close up views of the modular blades 36A, 46A, 56A shown in FIGS. 8- 10. As shown in FIG. 12, a blade 36A may comprise a blade axial length T, a blade circumferential thickness 't', and a blade radial width 'w'. A number of blade fastener receiving holes 361 may be provided to the blade 36A, which are configured to receive blade fasteners 36F which extend through blade fastener clearance holes 66G. As shown in FIG. 13, a blade 46A may comprise a blade axial length T, a blade circumferential thickness 't', and a blade radial width 'w'. A number of blade fastener receiving holes 461 may be provided to the blade 46A, which are configured to receive blade fasteners 46F which extend through blade fastener clearance holes 66G. A number of blade apertures 46B (e.g., radially-elongated slots) may be provided to the blade. The blade apertures 46B may comprise a blade aperture axial length 'a' and a blade aperture radial length 'b'. The lengths 'a' and 'b' may differ between apertures 46B, or may be similar between different apertures 46B. Apertures 46B may be radially- aligned as shown, or may be staggered as will be shown in FIG. 14. As shown in FIG. 14, a blade 56A may comprise a blade axial length T, a blade circumferential thickness 't', and a blade radial width 'w'. A number of blade fastener receiving holes 561 may be provided to the blade 56A, which are configured to receive blade fasteners 56F which extend through blade fastener clearance holes 66G. A number of blade apertures 56B (e.g., radially-elongated slots) may be provided to the blade. The blade apertures 56B may comprise a blade aperture axial length 'a' and a blade aperture radial length 'b'. The lengths 'a' and 'b' may differ between apertures 56B, or may be similar between different apertures 56B. Apertures 56B may be radially- staggered as shown, or may be aligned as shown in FIG. 13. Rather than small staggered apertures 56B shown in FIG. 14, larger/longer apertures (not shown) may be provided and aligned. In other words, radial lengths 'b' of apertures 56B may be increased, or decreased from what is shown, radial lengths 'a' of apertures 56B may be increased, or decreased from what is shown, apertures 56B may be rotated in angle in any number of degrees of freedom within or outside of a plane of blade 56A, and/or shapes of apertures 56B may be different from what is shown (e.g., circular, rectangular, trapezoidal, triangular, polygonal, etc.), without limitation.

Moreover, in some embodiments, aperture 56B shapes, sizes, and/or orientations may change on the same blade 56A. Furthermore, in some embodiments, aperture 56B shapes, sizes, and/or orientations may change between blades (e.g., blade configurations may change according to circumferential position within disperser 10, 20, 30, 40, 50.

FIGS. 15 and 16 suggest a disperser 70 according to some embodiments, wherein one or more blades 76A may be welded at their upper ends and/or their lower ends, to one or more rings, for example, rings comprising a shelf 75, 75', as illustrated. It should be understood that the one or more rings may comprise forms other than what is shown, and may not comprise a shelf 75, 75'. Accordingly, in some embodiments, blade fasteners 76F may comprise welds, without limitation. Alternatively, the blade fasteners 76F may comprise other hardware shown and/or described herein, wherein the one or more blades 76A may be modular in nature. As shown in FIGS. 15 and 16, embodiments of a disperser 70 may not comprise blades 76A are which are attached to a segmented tubular portion, but are independently provided in a radial arrangement, and therefore, in some embodiments, a disperser 70 may not comprise a tubular portion 16C, 26C, 36C, 46C, 56C, 66C as with in other embodiments. The blades 76A are preferably circumferentially- spaced by a uniform circumferential blade spacing 'c', and extend radially-inwardly for a blade radial width 'w'. In some embodiments, the radial width 'w' of each blade 76A may vary. In some embodiments, the blades 76 may not extend exactly radially (e.g., may be curved and/or angled with respect to a radial direction, without limitation. Each blade 76A comprises a blade axial length T and a blade circumferential thickness 't'. Blades 76A may also comprise one or more blade apertures 76B, such as radially-elongated slots as shown. In some preferred embodiments, the one or more blade apertures 76B are larger in a radially-extending direction than an axially-extending direction as shown. Also as shown, in some embodiments, the one or more blade apertures 76B may be aligned (e.g., so as to share a common radial location as shown). In some embodiments, the one or more blade apertures 76B may be staggered within a particular blade 76A, for example, in a "packing" arrangement, without limitation. Blades 76A may be radially offset from an inner or outer surface or edge of a lower shelf 75'. Blades 76A may be radially offset relative to an inner or outer surface or edge of an upper shelf 75, without limitation. The disperser 70 may comprise a plurality of orifices 72, which may be rectangular or may comprise a trapezoidal polyhedron or three- dimensional "wedge" shape, and the plurality of orifices 72 may define one or more openings created between shelves 75, 75' and blades 76A. The orifices 72 may have an orifice width Y which is less than an orifice height 'y' (as shown). A second set of holes may be provided for attachment of a mounting a hood (not shown) or securing the disperser 70 within a flotation cell. According to some embodiments, orifices 72' may extend through the lower shelf 75', for example, in a vertical or "axial" direction, respective to the disperser 70. According to some embodiments, the lower shelf 75' may not extend across the entire width of the blades as shown, but may extend across various portions of the widths of the blades 76A, without limitation. According to some embodiments (not shown), the lower shelf 75' may be replaced with a ring welded to the lower inner diameter corners of the blades, and/or a ring welded to the lower outer diameter corners of the blades. According to some embodiments, a plurality of radially-aligned orifices 72' may extend radially along a lower shelf 75' as shown, however, it is envisaged that only one of a plurality of orifices 72' may be located at a particular radial location. The actual number of the plurality of orifices 72' may be greater than, or less than the number shown, for example, a single orifice 72' may be utilized, without limitation. It should be appreciated that the orifices 72' may be provided in shapes, sizes, orders, arrangements, or configurations other than what is shown. For example, the orifices 72' may be rectangular or square in shape. For example, the orifices may be provided in a "packing" arrangement. In some embodiments, the sizes of the orifices 72' may be varied throughout the lower shelf 75', or the sizes of the orifices 72' may be uniform throughout the lower shelf 75'. Moreover, in some embodiments, the orifices 72' may be rectangular and arranged with their longest side extending in a radial direction. In some embodiments, the orifices 72' may be rectangular and may be arranged with their longest side extending in a tangential or circumferential direction, without limitation.

FIGS. 17-22 suggest a disperser 80 and various components thereof, according to some embodiments. The disperser 80 may, as shown, comprise a framework 83 surrounded by a tubular portion 86C, which may be subsequently covered in a resistant layer 89 (e.g., polymer and/or an elastomer, such as urethane, without limitation). The framework 83 may comprise a number of blades 88A connected at their bottoms, to at least one lower shelf 85'. While a plurality of lower shelves 85' may be provided, only one lower shelf is shown. The at least one lower shelf 85' may comprise the form of an annular ring. The number of blades 88A may be connected at their tops, to an annular upper shelf 85, as shown. The framework 83 may be surrounded by the tubular portion 86C, and joined to it, for example, via tack welding, holding fasteners (e.g., clips), or via interference fit. The framework 83 and the tubular portion 86C may comprise a metal, a polymer, or a combination thereof; however, in some more preferred commercial embodiments, the framework 83 and/or tubular portion 86C may be formed of steel, without limitation. The framework 83 and/or tubular portion 86C assembly may be joined together and subsequently covered in a resistant material, such as a urethane material, without limitation. The tubular portion 86, if used, may comprise a number of orifices 82. The effective area of orifices 82 may shrink in size after resistant material is applied to the tubular portion 86C (e.g., via overmoulding, spraying application, bonding application, or the like, without limitation). One, some, or all of the number of blades 88A may comprise one or more blade apertures 86B, such as one or more openings (e.g., one or more rectangular openings as shown) which may be configured as radially-elongated slots, without limitation. Any number of blades 88A may comprise upper and/or lower blade shoulders 87; for example, to provide rigidity, provide support, improve strength, and/or to connect to upper and/or lower shelves 85, 85', without limitation.

FIGS. 23a-23b suggest a disperser 90 and components thereof, according to some embodiments, comprising a lower shelf 95' which may be provided as a ring, and an upper shelf 95, wherein wide blades may be welded or otherwise fastened (e.g., via fasteners and/or clips) to the lower 95' and/or upper 95 shelves. While a plurality of lower shelves 95' may be provided, only one lower shelf is shown. In some instances, reinforcing bars secured between blades may be utilized instead of the annular lower shelf 95' shown. Orifices 92, which may be defined by the spacings between blades 98A, may provide an area of ingress and/or egress of slurry which may be at least partially aerated. A tubular portion may be provided, or may not be provided with the disperser 90 (as shown). The disperser 90 may be covered (e.g., via applying, coating, spraying, dipping, molding, etc.) with a resilient material, such as a urethane material, without limitation. Other resilient materials known in the art, which have some resistance to wear and/or chemicals are anticipated.

FIGS. 24a-24b suggest an alternative disperser 100 and components thereof, according to some embodiments. The disperser 100 may be similar to the aforementioned disperser 90 embodiment of FIGS. 23a-23b, wherein narrower blades may be provided. In some instances, the blades may have fewer orifices therein, and/or the pattern of the orifices may differ or vary, without limitation. The disperser 100, according to some embodiments, may comprise a lower shelf 105' which may be provided as a ring, and an upper shelf 105, wherein narrow blades may be welded or fastened (e.g., via fasteners and/or clips) to the lower 105' and/or upper 105 shelves. While a plurality of lower shelves 105' may be provided, only one lower shelf is shown. In some instances, reinforcing bars secured between blades may be utilized instead of the annular lower shelf 105' shown. Orifices 102, which may be defined by the spacings between blades 108A, may provide an area of ingress and/or egress of slurry which may be at least partially aerated. A tubular portion may be provided, or may not be provided with the disperser 100 (as shown). The disperser 100 may be covered (e.g., via applying, coating, spraying, dipping, molding, etc.) with a resilient material, such as a urethane material, without limitation. Other resilient materials known in the art, which have some resistance to wear and/or chemicals are anticipated.

While not expressly shown, it should be understood that the disperser apparatus, disperser assemblies, and/or components thereof described and shown in the drawings may be provided in duplicates. For example, multiple blades may be provided to a disperser tubular portion at the same circumferential location (i.e., being axially- spaced along direction T rather than

circumferentially spaced by shown spacing 'c'. It should also be known that while a flotation cell is not expressly shown and described in the drawings and aforementioned specification, one having an ordinary skill in the art would readily appreciate that the dispersers 10, 20, 30, 40, 50 disclosed would preferably be positioned in a central portion of the flotation (not at the bottom), as typically done for self-aspirated flotation machines. Moreover, while not shown, an annular reinforcing ring may be provided at upper, radially-inward portions of blades in order to increase disperser rigidity and to keep the blades from fluctuating and breaking as demonstrated in copending application PCT/DK2013/050360. For the particular embodiments shown in the drawings, it will be understood that the blades may alter shear characteristics due to a decreasing gap between the rotor and disperser. The below table shows example shear values calculated from test-sized conventional rotors (i.e., having an OD of 64.7 mm with a tip speed of 3.99 m/s) when used with conventional dispersers, as compared to dispersers disclosed herein:

The below table further shows measured shear-recovery:

A contractor or other entity may provide a disperser apparatus or operate a disperser apparatus in whole, or in part, as shown and described. For instance, the contractor may receive a bid request for a project related to designing or operating a disperser apparatus, or the contractor may offer to design any number of disperser apparatuses or components thereof, or a process for a client involving one or more of the features shown and described herein. The contractor may then provide, for example, any one or more of the devices or features thereof shown and/or described in the embodiments discussed above. The contractor may provide such devices by selling those devices or by offering to sell those devices. The contractor may provide various embodiments that are sized, shaped, and/or otherwise configured to meet the design criteria of a particular client or customer. The contractor may subcontract the fabrication, delivery, sale, or installation of a component of the devices disclosed, or of other devices used to provide said devices. The contractor may also survey a site and design or designate one or more storage areas for storing the material used to manufacture the devices, or for storing the devices and/or components thereof. The contractor may also maintain, modify, or upgrade the provided devices. The contractor may provide such maintenance or modifications by subcontracting such services or by directly providing those services or components needed for said maintenance or modifications, and in some cases, the contractor may modify a preexisting disperser apparatus or disperser apparatus of a flotation circuit, subassemblies thereof, components thereof, and/or parts thereof with one or more "retrofit kits" to arrive at a modified valve apparatus or method of operating a disperser apparatus comprising one or more method steps, devices, components, or features of the systems and processes discussed herein.

Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding the scope of the claimed. Accordingly, it is to be understood that the drawings and descriptions herein are proffered by way of example to facilitate comprehension of the invention and should not be construed to limit the scope thereof. REFERENCE NUMERAL IDENTIFIERS a Blade aperture axial length

b Blade aperture radial length

c Circumferential blade spacing

d Blade axial offset

1 Blade axial length

t Blade circumferential thickness

w Blade radial width

X Orifice width

y Orifice height

10, 20, 30, 40, 50, 70, 80, 90, 100 Disperser

11, 21 Mounting ring

12, 22, 32, 42, 52, 62, 72, 72', 82, 92, 102 Orifices

13, 23 Outer chamfer

14, 24 Inner chamfer

15, 25, 75, 75', 85, 85', 95, 95', 105, 105' Shelf

16A, 26A, 36A, 46A, 56A, 76A, 88A, 98A, Blades

16B, 26B, 46B, 56B, 76B, 86B Blade aperture (e.g., radially-elongated slot)

16C, 26C, 86C Tubular portion

17, 27 Mounting boss

18, 28, 78 First set of holes

19, 29, 39, 49, 59, 69 Second set of holes

36C, 46C, 56C Segmented tubular portion

36D, 46D, 56D, 66D Flange

36E, 46E, 56E Flange fasteners

36F, 46F, 56F, 76F Blade fasteners

361, 461, 561 Blade fastener receiving holes

66C Segmented tubular portion segment

66G Blade fastener clearance holes

66H Flange fastener clearance holes

83 Framework

89 Resistant layer (e.g., polymer, elastomer)

87 Blade shoulder

900, 2900 Rotor

910, 1910, 2910 Disperser

912, 1912, 2912 Orifices

914 Half bar

2920 Hood

Claims

CLAIMS WHAT IS CLAIMED IS:

1. A retrofittable disperser apparatus [10] for a self-aspirated flotation cell comprising: a disperser assembly having a tubular portion [16C], a number of orifices [12] extending through the tubular portion [16C], and a number of blades [16A] extending radially- inwardly from the tubular portion [16C].

2. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 1, wherein at least one of said number of blades [16A] extending radially- inwardly from the tubular portion [16C] comprises a number of blade apertures [16B].

3. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 2, wherein the number of blade apertures [16B] comprises a number of elongated slots having an axial length [a] less than a radial length [b].

4. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 3, wherein the number of blade apertures [16B] are arranged so as to be in axial alignment with each other at a similar radial location.

5. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 3, wherein the number of blade apertures [16B] are arranged so as to be staggered with at least two blade apertures sharing different radial locations.

6. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 2, wherein said number of blade apertures [16B] comprises a number of rectangular- shaped or oval shaped blade apertures [16B].

7. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 1, further comprising a mounting ring [11] for securing a hood thereto.

8. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 7, further comprising a radially-extending shelf [15] extending between the mounting ring [11] and the tubular portion [16C].

9. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 7, wherein the mounting ring [11] further comprises one or more mounting bosses [17].

10. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 7, wherein the mounting ring [11] further comprises a first set [18] of holes.

11. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 1, wherein the tubular portion [16C] further comprises a second set [19] of holes.

12. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 1, wherein said number of orifices [12] comprise one or more outer chamfers [11] or one or more inner chamfers [14].

13. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 2, wherein said number blades [16A] extending radially-inwardly from the tubular portion [16C] comprises blades [16A] having a blade axial length [1], a blade radial width [w], and a blade circumferential thickness [t].

14. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 13, wherein said blade axial length [1] is greater than said blade radial width [w] and blade circumferential thickness [t].

15. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 13, wherein said blade radial width [w] is greater than said blade circumferential thickness [t].

16. The retrofittable disperser apparatus [10] for a self-aspirated flotation cell according to claim 13, wherein said number of blade apertures [16B] are at least as long in a radial direction as said circumferential thickness [t].

17. The retrofittable disperser apparatus [30] for a self-aspirated flotation cell according to claim 1, wherein said number of blades [36A] are modular and configured to be attached to the tubular portion [36C] via a number of blade fasteners [36F].

18. The retrofittable disperser apparatus [30] for a self-aspirated flotation cell according to claim 1, wherein said number of blades [36A] are modular and configured to be attached to the tubular portion [36C] via a number of blade fasteners [36F].

19. The retrofittable disperser apparatus [30] for a self-aspirated flotation cell according to claim 1, wherein said tubular portion [36C] is modular and comprised of a number of segmented tubular portion segments [66C] configured to be attached to each other.

20. The retrofittable disperser apparatus [30] for a self-aspirated flotation cell according to claim 19, wherein said segmented tubular portion segments [66C] comprise at least one flange [66D].

21. The retrofittable disperser apparatus [30] for a self-aspirated flotation cell according to claim 20, wherein each segmented tubular portion segment [66C] comprises two flanges [66D], each flange [66D] having a number of flange fastener clearance holes [66H] for receiving a respective number of blade fasteners [36F]; wherein adjacent segmented tubular portion segments [66C] are connected by virtue of said blade fasteners [36F].

22. A self-aspirated flotation cell comprising a retrofittable disperser apparatus [10], the retrofittable disperser apparatus [10] comprising: a disperser assembly having a tubular portion [16C], a number of orifices [12] extending through the tubular portion [16C], and a number of blades [16A] extending radially-inwardly from the tubular portion [16C].

23. A method of flotation comprising:

providing a retrofittable disperser apparatus [10] to a self-aspirated flotation cell, the retrofittable disperser apparatus [10] comprising: a disperser assembly having a tubular portion [16C], a number of orifices [12] extending through the tubular portion [16C], and a number of blades [16A] extending radially-inwardly from the tubular portion [16C];

providing a rotor within said retrofittable disperser apparatus [10];

providing slurry containing mineral, gangue, and a reagent to the self-aspirated flotation cell; and,

floating the mineral from the gangue by virtue of rotating the rotor;

wherein, during operation, shear to the slurry is substantially increased thereby substantially increasing recovery.

24. A retrofittable disperser apparatus [70] for a self-aspirated flotation cell, the retrofittable disperser apparatus [70] comprising: a disperser assembly having a lower shelf [75'], a number of orifices [72'] extending through the lower shelf [75'], and a number of blades [76A] extending radially-inwardly; wherein the number of blades [76A] extend upwards from the lower shelf [75'].