WO2021222981A1

WO2021222981A1 - Mine site comminution arrangement and methodology

Info

Publication number: WO2021222981A1
Application number: PCT/AU2021/050414
Authority: WO
Inventors: Heath Lawrence WILLIAMS; John Alec SEXTON
Original assignee: Leschenault Industries Pty Ltd
Priority date: 2020-05-05
Filing date: 2021-05-05
Publication date: 2021-11-11
Also published as: AU2021267559A1; AU2021267559B2

Abstract

Provided is a comminution arrangement (10) for a mine site, said arrangement (10) comprising a feed bin (12) for receiving mined material. Feed bin (12) comprises a grizzly (14) at an upper portion thereof configured to allow material below a predetermined size to pass whilst filtering larger material, and a rockbreaker (16) proximate the grizzly for reducing such filtered larger material below the predetermined size. Feed bin (12) also includes an apron feeder (18) at a lower portion thereof for regulating feeding of material, and a vibrating grizzly feeder (20) operatively fed with material from the apron feeder (18). Arrangement (10) also includes a stacker conveyor (22) configured to receive material from the grizzly feeder (20), said stacker conveyor (22) feeding a radial stacker (24) for stacking at least one ore stockpile (26) with material. For each ore stockpile (26), a stockpile reclaim conveyor (30) is arranged within a reclaim tunnel (32) below the stockpile (26) and is configured to selectively convey material from such a stockpile (26). Finally, arrangement (10) includes a crusher feed conveyor (34) operatively fed with material from at least one stockpile reclaim conveyor (30), said crusher feed conveyor (34) for supplying Run of Mine (ROM) to a primary crusher (36).

Description

MINE SITE COMMINUTION ARRANGEMENT AND METHODOLOGY

TECHNICAL FIELD

[0001] This invention relates to the field of mining, in general, and more specifically to a comminution arrangement for a mine site, a comminution methodology, a mine site having such a comminution arrangement and a method of mining comprising such a comminution methodology.

BACKGROUND ART

[0002] The following discussion of the background art is intended to facilitate an understanding of the present invention only. The discussion is not an acknowledgement or admission that any of the material referred to is or was part of the common general knowledge as at the priority date of the application.

[0003] In the field of mining, valuable minerals are often extracted from rock via the process of comminution, which is the general reduction of solid materials from one average particle size to a smaller average particle size, typically through crushing, grinding, cutting, vibrating, or other processes.

[0004] In the mining and mineral processing sector, most energy use and greenhouse gas emissions derive from comminution, separation (froth flotation) and concentrate drying. Of these areas, comminution is the most energy intensive. In some mining sub-sectors, such as gold, copper and nickel, comminution comprises over 70% of total energy use. Additional energy is needed to mine and process ore grades of declining quality. As well as being less profitable or cost-effective, this situation increases the energy embodied in primary metal production and its associated greenhouse gas emissions.

[ 0005 ] According to industry studies, comminution accounts for 3% of the entire world's energy consumption and comminution accounts, on average, for more than 50% of a mine's energy consumption and around 10% of total production costs. Comminution energy costs are forecast to increase significantly over the next decade due to the overall trend of declining ore grades.

[ 0006 ] Accordingly, comminution costs could be better managed through adopting more efficient comminution processes and technologies. As mines rarely have control over the cost of energy, such as electricity and fuel costs, it is vital that comminution processes meet process objectives while consuming as little energy as possible.

[ 0007 ] For example, in a typical mining environment, such as an iron ore mine, Run of Mine (ROM) is delivered to a primary crusher by haul trucks, conveyors and related material moving equipment. At the ROM pad, mined material or ROM is dumped into a primary crusher where large rock fragments are broken into smaller sizes. Crushing to the proper size usually occurs in stages as rapid size reduction, accomplished by applying large forces, commonly results in the production of excessive fines. For this reason, after primary crushing, the material is typically run through one or more secondary crushers. The material is screened after each crushing cycle to separate properly sized particles ("throughs") from those needing additional crushing ("overs"). Additional washing, screening, or other processing may be required to remove undesirable material. The crushed material is then stockpiled awaiting shipment.

[0008] In such an example, any delays at the primary crusher generally delays the entire processing of mined ore, which delays mine production and has significant adverse financial effects. Examples of delays include oversized rocks delivered to the primary crusher, foreign material entering the crusher (such as ground engaging tools or GET that combine with ore during the mining process), continuity of delivering mined material to the crusher, and the like.

[0009] Accordingly, ensuring continuous supply of high- quality ROM to the primary crusher or similar processing will generally result in increased mine production and efficiency. The current invention was conceived with this goal in mind and seeks to propose possible amelioration to conventional ROM supply practices.

SUMMARY OF THE INVENTION

[0010] The skilled addressee is to appreciate that reference herein to an apron feeder generally includes reference to a suitable feeder in which mined material is carried on an apron conveyor and in which the rate of feed is adjusted either by varying a depth of material or the speed of the conveyor, or both. Similarly, reference herein to Run of Mine (ROM) generally refers to ore that has been mined and ready to go to a mine processing plant, i.e. raw mined materials prior to processing by a mining processing plant, such as a primary crusher, or the like. [0011] According to a first aspect of the invention there is provided a comminution arrangement for a mine site, said arrangement comprising: a feed bin for receiving mined material and including: i) a grizzly at an upper portion thereof configured to allow material below a predetermined size to pass whilst filtering larger material; ii) an apron feeder at a lower portion thereof for regulating feeding of material; and iii) a vibrating grizzly feeder operatively fed with material from the apron feeder; a stacker conveyor configured to receive material from the grizzly feeder, said stacker conveyor feeding a radial stacker for stacking at least one ore stockpile with material; for each ore stockpile, a stockpile reclaim conveyor arranged within a reclaim tunnel below said stockpile and configured to selectively convey material from such stockpile; and a crusher feed conveyor operatively fed with material from at least one stockpile reclaim conveyor, said crusher feed conveyor for supplying Run of Mine (ROM) to a primary crusher.

[0012] In an embodiment, the feed bin is sized and dimensioned to receive mined material from a plurality of haul trucks simultaneously.

[0013] In one embodiment, the feed bin is sized and dimensioned to accommodate five haul trucks simultaneously dumping mined material therein.

[0014] Typically, the feed bin defines a funnel-like structure for guiding received material towards the apron feeder under the influence of gravity. [0015] In an embodiment, the arrangement comprises a rockbreaker proximate the grizzly for reducing the filtered larger material below the predetermined size.

[0016] Typically, the rockbreaker comprises a mobile and/or stationary rockbreaker, i.e. mounted on a pedestal or slew frame, and/or mounted on an excavator platform.

[0017] Typically, the grizzly is configured such that the predetermined size of material is selectable according to mining process requirements.

[0018] Typically, the apron feeder is configured to regulate and control a rate of feeding of material from the feed bin to the vibrating grizzly feeder.

[0019] Typically, the stacker conveyor stacks three to five ore stockpiles.

[0020] In an embodiment, the stacker conveyor stacks the ore stockpiles according to a grade of material, e.g. a high- grade stockpile, a medium grade stockpile, a low-grade stockpile, etc.

[0021] Typically, the stacker conveyor includes at least one belt magnet configured to remove unwanted magnetic material from the conveyed material.

[0022] Typically, the at least one belt magnet is arranged along a length of the stacker conveyor between the grizzly feeder and the radial stacker. [0023] Typically, each stockpile reclaim conveyor is selectively operable to allow blending of material conveyed to the crusher feed conveyor.

[0024] In an embodiment, the crusher feed conveyor includes at least one secondary belt magnet configured to remove unwanted magnetic material from the conveyed material.

[0025] Typically, the feed bin is arranged at a higher level, the radial stacker at an intermediate level, and the stockpiles and crusher feed conveyor at a lower level relative to each other on the mine site.

[0026] According to a second aspect of the invention there is provided a comminution methodology comprising the steps of: receiving, via a feed bin, mined material, said feed bin comprising: i) a grizzly at an upper portion thereof configured to allow material below a predetermined size to pass whilst filtering larger material; ii) an apron feeder at a lower portion thereof for regulating feeding of material; and iii) a vibrating grizzly feeder operatively fed with material from the apron feeder; stacking, via a radial stacker fed by a stacker conveyor which receives material from the grizzly feeder, at least one ore stockpile with material; selectively reclaiming from a stockpile, via a stockpile reclaim conveyor arranged within a reclaim tunnel below said stockpile, material from a desired stockpile; and feeding, via a crusher feed conveyor operatively fed with material from a stockpile reclaim conveyor, Run of Mine (ROM) material to a primary crusher. [0027] Typically, the step of receiving comprises receiving mined material from a plurality of haul trucks simultaneously .

[0028] Typically, the method includes the step of reducing a size of larger material filtered by the grizzly via a rockbreaker positioned proximate the grizzly for reducing such filtered larger material below the predetermined size.

[0029] Typically, the step of stacking comprises stacking three to five ore stockpiles.

[0030] In an embodiment, the step of stacking comprises stacking the ore stockpiles according to a grade of material, e.g. a high-grade stockpile, a medium grade stockpile, a low- grade stockpile, etc.

[0031] Typically, the method includes the step of removing unwanted magnetic material, via a belt magnet, from the material conveyed on the stacker conveyor.

[0032] Typically, the step of selectively reclaiming comprises reclaiming from each stockpile, via a stockpile reclaim conveyor, to allow blending of material conveyed to the crusher feed conveyor.

[0033] According to a third aspect of the invention there is provided a mine site having a comminution arrangement in accordance with the first aspect of the invention above.

[0034] According to a fourth aspect of the invention there is provided a method of mining comprising a comminution methodology in accordance with the second aspect of the invention above.

BRIEF DESCRIPTION OF THE DRAWINGS

The description will be made with reference to the accompanying drawings in which:

Figure 1 is a diagrammatic perspective overview representation of a comminution arrangement for a mine site, in accordance with an aspect of the present invention;

Figure 2 is a diagrammatic perspective sectional representation of the arrangement of Figure 1;

Figure 3 is diagrammatic side sectional representation of a feed bin of the arrangement;

Figure 4 is a diagrammatic front view sectional representation of the feed bin of Figure 3;

Figure 5 is a diagrammatic side sectional overview representation of the arrangement of Figure 1;

Figure 6 is a diagrammatic front view representation of the arrangement of Figure 1; and

Figure 7 is a diagrammatic top-view overview representation of the arrangement of Figure 1.

DETAILED DESCRIPTION OF EMBODIMENTS

[0035] Further features of the present invention are more fully described in the following description of several non- limiting embodiments thereof. This description is included solely for the purposes of exemplifying the present invention to the skilled addressee. It should not be understood as a restriction on the broad summary, disclosure or description of the invention as set out above. In the figures, incorporated to illustrate features of the example embodiment or embodiments, like reference numerals are used to identify like parts throughout.

[ 0036 ] Broadly, where conventional mining practices often see mined material or ROM being delivered directly by haul trucks to a primary crusher, the present invention is intended to function as an intermediary comminution arrangement which provides benefits as described below. The skilled addressee will have mining experience and, as a result, technology and concepts well-known in the field of mining will not be described herein in any detail.

[ 0037 ] Referring now to the accompanying figures, there is shown an embodiment of a comminution arrangement 10 for a mine site, in accordance with aspects of the present invention. The arrangement 10 generally comprises a feed bin 12 for receiving mined material, a stacker conveyor 22, a radial stacker 24 for stacking stockpiles 24, stockpile reclaim conveyors 30, and a crusher feed conveyor 34 for feeding a primary crusher 36.

[ 0038 ] In a typical example, the feed bin 12 comprises a grizzly 14 at an upper portion thereof (shown more clearly in Figures 3 and 4) which is configured to allow material below a predetermined size to pass into feed bin 12 whilst filtering larger material, and a rockbreaker 16 proximate the grizzly 14 for reducing such filtered larger material below the predetermined size so that it may pass into the bin 12. [0039] The rockbreaker 16 may comprise a mobile and/or stationary rockbreaker, i.e. mounted on a pedestal or slew frame, and/or mounted on an excavator platform, or the like, as is known in the art. The rockbreaker 16 generally reduces larger material below the predetermined size as such larger material lies on the grizzly 14, or it may do so on a surface besides or proximate the grizzly before such reduced material is transferred by means of front-end-loader, or the like, into the feed bin 12, onto the grizzly, etc. The skilled addressee is to appreciate that variations hereon are possible and expected and within the scope of the present invention.

[0040] Feed bin 12 further typically includes an apron feeder 18 at a lower portion thereof, as shown, for regulating feeding of material, and a vibrating grizzly feeder 20 which is operatively fed with material from the apron feeder 18.

[0041] Arrangement 10 then features a stacker conveyor 22 which is configured to receive material from the grizzly feeder 20, with said stacker conveyor 22 for feeding a radial stacker 24 with material from the feed bin 12 for stacking on at least one ore stockpile 26.

[0042] For each ore stockpile 26, arrangement 10 includes a stockpile reclaim conveyor 30 which is arranged within a reclaim tunnel 32 below that particular stockpile 26 and which is configured to selectively convey material from such a stockpile 26. Finally, arrangement 10 includes a crusher feed conveyor 34 which is operatively fed with material from at least one stockpile reclaim conveyor 30, requirements depending, with the crusher feed conveyor 34 supplying Run of Mine (ROM) to a primary crusher 36.

[0043] The feed bin 12 is typically sized and dimensioned to receive mined material from a plurality of haul trucks simultaneously. In one embodiment, the feed bin 12 may be sized and dimensioned to accommodate, for example, five haul trucks simultaneously dumping mined material therein. Variations hereon are possible and within the scope of the invention .

[0044] As seen in Figure 4, the feed bin 12 typically defines a funnel-like structure for guiding received material towards the apron feeder 18 under the influence of gravity. The grizzly 14 is generally configured such that the predetermined size of material is selectable according to mining process requirements, e.g. 500mm, or the like. The apron feeder 18 is generally configured to regulate and control a rate of feeding of material from the feed bin 12 to the vibrating grizzly feeder 20, as is known in the art.

[0045] Depending on mine requirements, the stacker conveyor 22 typically stacks three to five ore stockpiles 26, although variations hereon as possible and expected. In an embodiment, the stacker conveyor 22 stacks the ore stockpiles 26 according to a grade of material, e.g. a high-grade stockpile, a medium grade stockpile, a low-grade stockpile, etc. The stacker conveyor 22 also generally includes at least one belt magnet 28 which is configured to remove unwanted magnetic material, such as GET gear, from the conveyed material. Typically, the at least one belt magnet 28 is arranged along a length of the stacker conveyor 22 between the grizzly feeder 20 and the radial stacker 24. The skilled addressee is to appreciate that a plurality of belt magnets may be arranged as desired along the stacker conveyor 24. Variations on the number and location (s) of the at least one belt magnet 28 are possible and within the scope of the present invention.

[0046] In a typical example, each stockpile reclaim conveyor 30 is selectively operable to allow blending of material conveyed to the crusher feed conveyor 34. In one embodiment, the crusher feed conveyor 34 also includes at least one secondary belt magnet 38 which is additionally configured to remove unwanted magnetic material, such as GET gear, from the conveyed material. As with the at least one belt magnet 28 above, variations on a number and location (s) of the at least one secondary belt magnet 38 are possible and expected .

[0047] As shown in the accompanying figures, the feed bin 12 is arranged at a higher level, the radial stacker 24 at an intermediate level, and the stockpiles 26 and crusher feed conveyor 34 at a lower level relative to each other on the mine site. Such an arrangement facilitates operation of arrangement 10, as understood in the field of mine planning.

[0048] The present invention further includes a comminution methodology which generally comprises the steps of receiving mined material into feed bin 12, stacking (via radial stacker 14) at least one ore stockpile 26 with material, selectively reclaiming from a stockpile (via stockpile reclaim conveyor 30) material from a desired stockpile, and feeding (via crusher feed conveyor 34) Run of Mine (ROM) material to primary crusher 36.

[0049] As with arrangement 10 described above, such a methodology may include steps of receiving mined material from a plurality of haul trucks simultaneously, reducing a size of larger material filtered by the grizzly 14 via the rockbreaker 16, stacking three to five ore stockpiles 26 with radial stacker 24, and/or stacking the ore stockpiles 26 according to a grade of material, e.g. a high-grade stockpile, a medium grade stockpile, a low-grade stockpile, etc.

[0050] Similarly, the methodology may include the step of removing unwanted magnetic material, via belt magnet 18, from the material conveyed on the stacker conveyor 22, and/or the step of selectively reclaiming from each stockpile 26, via stockpile reclaim conveyor 30, to allow blending of material conveyed to the crusher feed conveyor 34.

[0051] The skilled addressee is to appreciate that the present invention extends towards a mine site having a comminution arrangement 10 as generally described and illustrated herein, as well as towards a method of mining comprising a comminution methodology described herein.

[0052] Applicant believes it particularly advantageous that the present invention provides for a comminution arrangement 10 and associated methodology which is able to function as intermediary between mined material and ROM supplied for mining processing, such as primary crushing. In this manner, arrangement 10 is able to provide a buffer against delays in supplying ROM, whilst also enabling blending of ROM material supplied to mining processing.

[0053] Optional embodiments of the present invention may also be said to broadly consist in the parts, elements and features referred to or indicated herein, individually or collectively, in any or all combinations of two or more of the parts, elements or features, and wherein specific integers are mentioned herein which have known equivalents in the art to which the invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth. In the example embodiments, well- known processes, well-known device structures, and well-known technologies are not described in detail, as such will be readily understood by the skilled addressee.

[0054] The use of the terms "a", "an", "said", "the", and/or similar referents in the context of describing various embodiments (especially in the context of the claimed subject matter) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms "comprising," "having," "including, " and "containing" are to be construed as open- ended terms (i.e., meaning "including, but not limited to,") unless otherwise noted. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. No language in the specification should be construed as indicating any non-claimed subject matter as essential to the practice of the claimed subject matter.

[0055] Spatially relative terms, such as "inner, " "outer, " "beneath, " "below, " "lower, " "above, " "upper, " and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature (s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the example term "below" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0056] It is to be appreciated that reference to "one example" or "an example" of the invention, or similar exemplary language (e.g., "such as") herein, is not made in an exclusive sense. Various substantially and specifically practical and useful exemplary embodiments of the claimed subject matter are described herein, textually and/or graphically, for carrying out the claimed subject matter.

[0057] Accordingly, one example may exemplify certain aspects of the invention, whilst other aspects are exemplified in a different example. These examples are intended to assist the skilled person in performing the invention and are not intended to limit the overall scope of the invention in any way unless the context clearly indicates otherwise. Variations (e.g. modifications and/or enhancements) of one or more embodiments described herein might become apparent to those of ordinary skill in the art upon reading this application. The inventor (s) expects skilled artisans to employ such variations as appropriate, and the inventor(s) intends for the claimed subject matter to be practiced other than as specifically described herein.

[0058] Any method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.

Claims

1. A comminution arrangement for a mine site, said arrangement comprising: a feed bin for receiving mined material and including: i) a grizzly at an upper portion thereof configured to allow material below a predetermined size to pass whilst filtering larger material; ii) an apron feeder at a lower portion thereof for regulating feeding of material; and iii) a vibrating grizzly feeder operatively fed with material from the apron feeder; a stacker conveyor configured to receive material from the grizzly feeder, said stacker conveyor feeding a radial stacker for stacking at least one ore stockpile with material; for each ore stockpile, a stockpile reclaim conveyor arranged within a reclaim tunnel below said stockpile and configured to selectively convey material from such stockpile; and a crusher feed conveyor operatively fed with material from at least one stockpile reclaim conveyor, said crusher feed conveyor for supplying Run of Mine (ROM) to a primary crusher.

2. The arrangement of claim 1, wherein the feed bin is sized and dimensioned to receive mined material from a plurality of haul trucks simultaneously.

3. The arrangement of claim 2, wherein the feed bin is sized and dimensioned to accommodate five haul trucks simultaneously dumping mined material therein.

4. The arrangement of any of claims 1 to 4, wherein the feed bin defines a funnel-like structure for guiding received material towards the apron feeder under the influence of gravity.

5. The arrangement of any of claims 1 to 5, which comprises a rockbreaker proximate the grizzly for reducing the filtered larger material below the predetermined size.

6. The arrangement of claim 5, wherein the rockbreaker comprises a mobile and/or stationary rockbreaker.

7. The arrangement of any of claims 1 to 6, wherein the grizzly is configured such that the predetermined size of material is selectable according to mining process requirements .

8. The arrangement of any of claims 1 to 7, wherein the apron feeder is configured to regulate and control a rate of feeding of material from the feed bin to the vibrating grizzly feeder.

9. The arrangement of any of claims 1 to 8, wherein the stacker conveyor stacks three to five ore stockpiles.

10. The arrangement of any of claims 1 to 9, wherein the stacker conveyor stacks the ore stockpiles according to a grade of material.

11. The arrangement of any of claims 1 to 10, wherein the stacker conveyor includes at least one belt magnet configured to remove unwanted magnetic material from the conveyed material.

12. The arrangement of claim 11, wherein the at least one belt magnet is arranged along a length of the stacker conveyor between the grizzly feeder and the radial stacker.

13. The arrangement of any of claims 1 to 12, wherein each stockpile reclaim conveyor is selectively operable to allow blending of material conveyed to the crusher feed conveyor.

14. The arrangement of any of claims 1 to 13, wherein the crusher feed conveyor includes at least one secondary belt magnet configured to remove unwanted magnetic material from the conveyed material.

15. The arrangement of any of claims 1 to 14, wherein the feed bin is arranged at a higher level, the radial stacker at an intermediate level, and the stockpiles and crusher feed conveyor at a lower level relative to each other on the mine site.

16. A comminution method comprising the steps of: receiving, via a feed bin, mined material, said feed bin comprising : i) a grizzly at an upper portion thereof configured to allow material below a predetermined size to pass whilst filtering larger material; ii) an apron feeder at a lower portion thereof for regulating feeding of material; and iii) a vibrating grizzly feeder operatively fed with material from the apron feeder; stacking, via a radial stacker fed by a stacker conveyor which receives material from the grizzly feeder, at least one ore stockpile with material; selectively reclaiming from a stockpile, via a stockpile reclaim conveyor arranged within a reclaim tunnel below said stockpile, material from a desired stockpile; and feeding, via a crusher feed conveyor operatively fed with material from a stockpile reclaim conveyor, Run of Mine (ROM) material to a primary crusher.

17. The method of claim 16, wherein the step of receiving comprises receiving mined material from a plurality of haul trucks simultaneously.

18. The method of either of claims 16 or 17, which includes the step of reducing a size of larger material filtered by the grizzly via a rockbreaker positioned proximate the grizzly for reducing such filtered larger material below the predetermined size.

19. The method of any of claims 16 to 18, wherein the step of stacking comprises stacking three to five ore stockpiles.

20. The method of any of claims 16 to 19, wherein the step of stacking comprises stacking the ore stockpiles according to a grade of material.

21. The method of any of claims 16 to 20, which includes the step of removing unwanted magnetic material, via at least one belt magnet, from the material conveyed on the stacker conveyor.

22. The method of any of claims 16 to 21, wherein the step of selectively reclaiming comprises reclaiming from each stockpile, via a stockpile reclaim conveyor, to allow blending of material conveyed to the crusher feed conveyor.

23. A mine site having a comminution arrangement in accordance with any of claims 1 to 15.

24. A method of mining comprising a comminution method in accordance with any of claims 16 to 22.