The entire contents of the patent specification (including drawings) of PCT/AU2019/051301 as originally filed is incorporated herein by reference.

Field of the Invention

The present invention relates generally to an apparatus and method for processing iron ore and more specifically, but not exclusively, to an apparatus and method for processing iron ore with lower cost and lower manning requirements during maintenance shutdown.

Background to the Invention

The present invention enables an ore processing system which is modular in that it replicates sub parts of the system rather than making each subpart larger. This change in established ideology enables the removal of surge bins and surge capacity as well as lower buildings in the plant resulting in lower plant costs as well as redundancy in the system such that the plant is able to be partially shut down for maintenance while still operating at reduced capacity.

Summary of the Invention

In accordance with one aspect of the present invention, there is provided an apparatus for processing iron ore having a sizer as a secondary crusher for crushing the iron ore.

In accordance with another aspect of the present invention, there is provided an apparatus for processing iron ore, including a mineral breaker as a secondary crusher for crushing the iron ore, wherein the mineral breaker includes a breaker drum mounted in a housing for breaking minerals into smaller pieces.

It will be appreciated by those skilled in the art that suitable mineral breakers may be referred to as a "sizer", a "roll crusher" or a "scroll crusher". Although the example depicted in the drawings uses a double/twin roll crusher, other examples may use more rolls, for example four or six rolls. Preferably, the mineral breaker has a pair of side by side breaker drums rotatably mounted in a housing. More preferably, the pair of breaker drums rotate in opposite directions to facilitate crushing of the minerals between the breaker drums. Even more preferably, each breaker drum is provided with circumferentially extending groups of breaker teeth, the groups being spaced axially along the breaker drum, the axial spacing of groups on one drum being staggered to that on the other drum so that the teeth in a group on one drum pass between an adjacent pair of groups on the other drum. The applicant has determined that it is of particular advantage to have the mineral breaker used in secondary stage crushing.

Preferably, the apparatus includes a gyratory crusher as a primary crusher. More preferably, the apparatus includes a cone crusher as a tertiary crusher. Preferably, the sizer is fed directly from a screen. In particular, the sizer may be fed directly from one or more scalping stage screens, as opposed to a grizzly screen that would commonly be seen in a primary crushing application. In a practical example, the secondary sizers will each be fed from one screen only.

In accordance with another aspect of the present invention, there is provided an apparatus for processing iron ore, including a primary crusher, a secondary crusher and a tertiary crusher, wherein the apparatus includes a pair of independently operable conveyors from the primary crusher to the secondary crusher (open circuit), from the secondary crusher to the tertiary crusher (open circuit), and/or from the tertiary crusher to a screen which feeds back to the tertiary crusher (closed circuit).

In accordance with another aspect of the present invention, there is provided an apparatus for processing iron ore, including a primary crusher, a secondary crusher and a tertiary crusher, wherein the apparatus includes a pair of independently operable conveyors from the primary crusher to the secondary crusher (open circuit), a pair of independently operable conveyors from the secondary crusher to the tertiary crusher (open circuit), and from three independently operable conveyors from the tertiary crusher to a screen which feeds back to the tertiary crusher (closed circuit). Preferably, in one example, the apparatus has a single primary crusher, multiple secondary crushers and multiple tertiary crushers. More preferably, in one example, the apparatus has a single primary crusher, two secondary crushers and three tertiary crushers. The applicant has identified that there is an upgrade path to readily expand the design to 2x Primary, 3x Secondary and 4x Tertiary. The example shown in the drawings is for a plant configuration for circa 30MTPA, however it will be appreciated that the plant can be expanded beyond this with the addition of crushing circuits. By virtue of the parallel processing, expansion of the plant configuration is facilitated.

In accordance with another aspect of the present invention, there is provided an apparatus for processing iron ore, including a primary crusher and a secondary crusher, wherein the secondary crusher is arranged to be fed from the primary crusher.

Preferably, the secondary crusher is arranged to be fed directly from the primary crusher. More preferably, the secondary crusher is fed directly from the primary crusher in that there is no bin to accumulate material to be fed to the secondary crusher. Adjustability of feed rate to suit each stage of crushing and screening may be achieved with variable speed drives on conveyors, feeders and/or crushers.

Alternatively, the secondary crusher is arranged to be fed directly from a screen used to filter material from the primary crusher according to material size.

In accordance with another aspect of the present invention, there is provided an apparatus for processing iron ore, including at least one conveyor, wherein each conveyor of the apparatus has a fixed single discharge point.

In accordance with another aspect of the present invention, there is provided an apparatus for processing iron ore, including a single yard belt located beneath a reversible stacker/reclaimer such that the single yard belt is configured to provide throughload functionality for loading the iron ore on a train, stacking functionality for stacking the iron ore on a stockpile, and reclaiming functionality for reclaiming iron ore from the stockpile to the train. In accordance with another aspect of the invention, there is provided an apparatus for processing iron ore, including a single belt arranged to transport iron ore material from a tertiary crusher, wherein the single belt is located beneath a reversible stacker/reclaimer such that the single belt is configured to provide throughload functionality for directly loading the iron ore material on a transport, stacking functionality for stacking the iron ore material on a stockpile, and reclaiming functionality for reclaiming iron ore material from the stockpile to the train. The belt may be fed from either primary, secondary or tertiary crusher.

The belt and stacker/reclaimer may operate in unison where the belt can through- load while also receiving ore from the stacker/reclaimer. Brief Description of the Drawings

The invention is described, by way of non-limiting example only, with reference to the accompanying drawings in which:

Figure 1 (A and B ) shows in a process flow diagram an example of an apparatus for processing iron ore in accordance with an example of the present invention; Figure 2 is an enlargement of the left half of Figure 1;

Figure 3 is an enlargement of the right half of Figure 1;

Figure 4 is a top perspective view showing a primary crusher of the apparatus;

Figure 5 is a top perspective view showing a secondary crusher of the apparatus;

Figure 6 is a top perspective view showing a tertiary crusher of the apparatus; Figure 7 is a top perspective view of a yard belt and a train loadout facility of the apparatus;

Figure 8 shows detail of the train loadout facility;

Figure 9 shows a distant top perspective overview of the primary, secondary and tertiary crushers, as well as conveyors between these stations; Figure 10 shows a distant top perspective view of the secondary crusher, the tertiary crusher, and an over land conveyor;

Figure 11 shows a distant top perspective view of the secondary crusher, the tertiary crusher, a total natural fines conveyor and a total generated fines conveyor; and

Figure 12 shows a plan view of the primary crusher, the secondary crusher, the tertiary crusher, the total natural fines conveyor, the total generated fines conveyor and part of the over land conveyor.

Detailed Description

With reference to Figures 1 to 12, there is shown an apparatus 10 for processing iron ore 12 having a sizer 14 as a secondary crusher for crushing the iron ore 12. Advantageously, the applicant has determined that using a sizer 14 as a secondary crusher enables large feed bins (of the type required for a cone crusher) to be obviated, as the sizer 14 does not require a constant rate of supply of iron ore material as does a cone crusher. In turn, as the bins are obviated and are typically large bins of great height, this enable the apparatus to be built with a low building height which reduces costs and facilitates reliability and maintenance.

The sizer 14 may be in the form of a twin shaft mineral sizer, being a mineral breaker 16 including a breaker drum 18 mounted in a housing 20 for breaking minerals into smaller pieces. More specifically, the mineral breaker 16 may have a pair of side by side breaker drums 18 rotatably mounted in the housing 20. In such an arrangement, the pair of breaker drums 18 rotate in opposite directions to facilitate crushing of the minerals between the breaker drums 18. Each breaker drum 18 may be provided with circumferentially extending groups of breaker teeth, the groups being spaced axially along the breaker drum 18, the axial spacing of groups on one drum 18 being staggered to that on the other drum 18 so that the teeth in a group on one drum 18 pass between an adjacent pair of groups on the other drum 18. The housing 20 may be fabricated from steel plate panels which are bolted and welded together. The breaker drums 18 may be geared at one end, one drum 18 geared relative to the other, so that they are driven from a common drive to be rotated in opposite directions. The drums 18 may be rotated so as to direct material between them. A gear connection between the drums may serve to set rotary positions of the drums 18 relative to one another. Teeth on the drums 18 may be arranged to define a series of discrete helical formations which are spaced circumferentially about each drum 18. The helical formations extend along the axis of each drum in a different sense, i.e. for a left hand drum the helical formations may extend away from the nearest end wall in an anti-clockwise sense and for a right hand drum the helical formations may extend in a clockwise sense. Each helical formation in extending along its respective drum may pass through an arc of about 90°.

Shaping of the teeth and their relative positions and size may be configured such that during use, two types of breaking actions are present - a primary breaking action on larger pieces of mineral where the mineral is gripped between opposing leading faces of teeth on opposite drums and a secondary breaking action wherein mineral material is trapped between the rear edges of teeth and the leading face of another tooth. The arc through which end helical formation passes is such as to ensure that a secondary breaking action occurs.

Spacing between the drums 18 may be chosen so that when the tips of teeth on one drum 18 sweep past the trough defined between groups of teeth on the other drum 18, there is sufficient clearance so that compaction of material is avoided. As such, with a suitable choice of spacing, it is possible for fine material to quickly pass through the sizer without compaction, thus leaving the sizer to break down larger pieces of material either by the primary and/or secondary breaking action.

Returning to Figure 1, the apparatus 10 may include a gyratory crusher 22 as a primary crusher. The apparatus 10 may include a cone crusher 24 as a tertiary crusher. The sizer 14 may be fed directly from a screen 26. Advantageously, no bin is required to feed the sizer 14 as the sizer does not require a constant rate of feed of iron ore material to be crushed. The screen 26 screens the iron ore material according to particle size, allowing smaller particle size material to bypass the sizer 14 as natural fines 28, whereas the remainder is then sorted according to scalping screen midds 30 and sizer feed 32. With reference to Figure 4, the primary crushing station may be cut into rock rather than having a retaining wall, and the gyratory crusher 22 may be mounted on a combination of steel and concrete, arranged to crush the iron ore material 12 into a large bin or bin 70. The large bin may have a waist and a pair of trouser leg funnels so as to divide the crushed ore between the two trouser leg funnels from which the crushed ore is fed to two separate scalping screen feed conveyors 34, as shown in Figure 1.

With reference to Figure 5, the scalping screen feed 34 comprises a pair of conveyors which transport the iron ore material 12 from the gyratory crusher 22 to the scalping screens 26. Advantageously, by having two conveyors, two scalping screens 26 and two sizers 14, this enables one of the conveyors to be shut down for maintenance while the other conveyor operates such that the entire apparatus 10 is able to function for online maintenance. This is significant as it means that the apparatus does not require such a large number of personnel to carry out the maintenance, meaning that it possible to optimise the skills of the maintenance force and to avoid mistakes which may otherwise occur owing to lack of skills (to achieve a large work force) and/or rushing to complete maintenance while the apparatus is offline. The applicant foresees that, by virtue of the present invention, shutdown manning will be reduced from 700 people to 200 people for a given plant size. In the example shown in Figures 1 to 12, the plant is a 10 to 30 million tonne per annum plant.

With reference to Figures 1 to 3 and looking at the apparatus 10 in the upper half of the process flow diagram, the apparatus 10 includes a primary crusher 22, a secondary crusher 14 and a tertiary crusher 24, the apparatus 10 including a pair of independently operable conveyors from the primary crusher 22 to the secondary crusher 14, from the secondary crusher 14 to the tertiary crusher 24, and three conveyors from the tertiary crusher 24 to the screen 40 which feeds back to the tertiary crusher 24. In the actual example of the invention illustrated, the apparatus 10 includes two conveyors from the primary crusher 22 to the secondary crusher 14, two conveyors from the secondary crusher 14 to the tertiary crusher 24, and three conveyors from the tertiary crusher 24 to the screen 40 which feeds back to the tertiary crusher 24. Furthermore, the apparatus 10 has a single primary crusher in the form of the single gyratory crusher 22, multiple secondary crushers in the form of the two sizers 14 and multiple tertiary crushers in the form of the three cone crushers 24. Accordingly, in the preferred example of the invention shown, the apparatus 10 has a single primary crusher, two secondary crushers and three tertiary crushers.

As will be appreciated by a person skilled in the art, the secondary crusher 14 is arranged to be fed from the primary crusher 22 and, more particularly, the secondary crusher 14 is arranged to be fed directly from the primary crusher in the sense that there is no bin for accumulation/regulation of iron ore material between the primary crusher 22 and the secondary crusher 14. As mentioned above, this is achieved by virtue of the applicant identifying that the sizer 14 does not require a constant rate of feed of iron ore material such that it is able to accommodate a potentially sporadic supply of iron ore material from the primary crusher 22. In turn, this has the advantage that large accumulation bins are not required, and because such bins are typically large, this results in a significant reduction in building height. Although bins are used in the form of tertiary crushing bins 36 to feed the cone crushers 24 of the tertiary crushing station, the tertiary crushing bins 36 are replicated as three bins in parallel (see Figure 1) such that the bins are smaller and the building is also correspondingly lower, as shown in Figure 6. By replicating and duplicating components rather than making single components larger, the applicant has achieved an efficient modular design resulting in a reduction in inventory.

Advantageously, the apparatus 10 includes at least one conveyor, wherein each conveyor of the apparatus 10 has a fixed single discharge point. This is in contrast to typical conveyors having moving conveyor parts, moving parts, and/or moving shuttles. The applicant has determined that by eliminating bins at the secondary crushing station and by reducing the size of bins at the tertiary crushing station, this promotes direct feed assets whereby the conveyors are not required to move to deliver material to a range of locations. A pair of conveyors terminate at locations corresponding to adjoining sides of the adjacent tertiary crushing bins 36 such that the iron ore material falls over the upper edges of the adjoining sides and is distributed between the three bins accordingly. In this way, feed from two separate conveyors is separated into three different feeds without the use of moving conveyors. Each of the three tertiary crushing bins 36 is fed to a separate cone crusher 24, and each cone crusher 24 feeds to a different one of the three product screen feed conveyors 38. As shown in the detail of Figure 2, the secondary crusher 14 is arranged to be fed directly from the screen 26 used to filter the iron ore material 12 from the primary crusher 22 according to material size.

The product screen feed conveyors 38 feed the iron ore material 12 to three separate screens 40 which determine whether the iron ore material 12 is to be directed to the total generated fines conveyor 42 or to be returned by feedback along the tertiary crusher feed conveyors 44 for further tertiary crushing.

The iron ore material on a total natural fines conveyor 46 and a total generated fines conveyor 42 are then fed to an over land conveyor 50 which, in turn, feeds to a stockyard conveyor 52. As can be seen in Figure 12, the total natural fines conveyor 46 and the total generated fines conveyor 42 run perpendicular to the conveyors between the primary, secondary and tertiary crushing stations. Also, the total natural fines conveyor 46 and the total generated fines conveyor 42 run perpendicular to the over land conveyor 50. Figure 12 also shows that the three conveyors feeding from the tertiary crushers to the screens 40 run between and alternately to the two tertiary crusher feed conveyors feeding from the secondary crushers 14 to the tertiary crushers 24. In this way, the feed direction is fed back 180 degrees at the tertiary crushing station so as to feed back onto itself and to minimise the footprint and size of the plant.

The stockyard conveyor 52 is in the form of a single yard belt located beneath a reversible stacker/reclaimer 54 such that the single yard belt is configured to provide throughload functionality for loading the iron ore on a train 58, stacking functionality for stacking the iron ore on a stacking stockpile 56 (possibly by way of an additional stock piling conveyor to an additional stacking stockpile 56 as shown in Figure 1 and Figure 3), and reclaiming functionality for reclaiming iron ore from the stacking stockpile 56 to the train 58. The stockyard conveyor 52 includes a bypass chute 60 for bypassing the stacker/reclaimer 54 and is able to selectively feed iron ore material to a stacking conveyor 62 or to the bypass chute 60 in the event that the iron ore material to be fed directly to the train 58. The stacking conveyor 62 feeds iron ore material to a reversible conveyor 64 which, when driven forwards, feeds the iron ore material to a stock piling conveyor and thereby to the stacking stockpile 56. The stacker/reclaimer is able to be driven to take iron ore material from the stacking stockpile 56 and to feed it via the reversible conveyor 64 (driven in reverse) to the reclaim chute 66 through which the material is fed to the single yard belt which, in turn, feeds to the train loadout (TLO) facility 68.

Stage of crushing refers to the reduction of material or mineral size in a single process completed by one or more units of equipment.

Primary Stage could be either:

lx Gyratory Crusher

lx Jaw Crusher

2x Sizers (primary and secondary to produce a typical primary crusher ore)

Secondary Stage could be either per process stream:

lx Cone Crusher

lx Sizer

lx Double Roll Crusher

Tertiary Stage could be either per process stream:

lx Cone Crusher

lx HPGR

lx Mill

Particle Size Distribution (PSD):

Primary Stage Crushing: Feed - 1,500mm, Product - 270mm

Secondary Stage Crushing: Feed - 270mm, Product - 100mm

Tertiary Stage Crushing: Feed - 100mm, Product - 8mm

While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not by way of limitation. It will be apparent to a person skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. Thus, the present invention should not be limited by any of the above described exemplary embodiments. The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates.

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.

List of features

Apparatus for processing iron ore 10

Iron ore 12

Sizer 14

Mineral breaker 16

Breaker drums 18

Housing 20

Gyratory crusher 22

Cone crusher 24

Screen 26

Natural fines 28

Scalping screen midds 30

Sizer feed 32

Scalping screen feed 34

Tertiary crushing bins 36

Product screen feed conveyors 38

Screens 40

Total generated fines conveyor 42

Tertiary crusher feed conveyors 44

Total natural fines conveyor 46 Over land conveyor 50 Stockyard conveyor 52 Stacker/reclaimer 54 Stacking stockpile 56 Train 58

Bypass chute 60 Stacking conveyor 62 Reversible conveyor 64 Reclaim chute 66 Train loadout (TLO) facility 68 Large bin 70 Generated Tines 72 Product screen oversize 74 Stock piling conveyor 76 Train loadout (TLO) 78

Train loadout (TLO) direct 80

Reclaiming 82

Dual tip 84

Gate 86

Clamshell 88

Port 90

Reversible 92 150m ³ 94 Rail loop 96