FIELD OF THE INVENTION

Embodiments of the present invention pertain to improvements to dewatered tailings disposal and apparatus associated therewith. In particular, embodiments of the present invention relate to a unique and economical paste tailings disposal system/apparatus configured to work with greater than 3-degree beach slope angles, for example, 5-6 degree beach slope angles, whilst providing for tailings water ratios of 0.3 - 0.4 m ³ /tonne.

BACKGROUND OF THE INVENTION

Reference to background art herein is not to be construed as an admission that such art constitutes common general knowledge in the arts.

There remains a long-felt need to maximize beach slope angles for improved tailings disposal volumes at the tailings storage facility (TSF) using mobile equipment. Current ‘static perimeter’ or ‘wagon wheel’ paste tailings discharge designs are lacking. Thin lifts of tailings are required to safely place paste-like material at the TSF. This currently requires multiple nozzles which are carefully situated and periodically moved/shifted in an attempt to form the thin lifts. Thus, large amounts of manpower are typically required for existing paste tailings disposal operations and such operations seldom ly perform very well - only achieving 2-3 degree beach slope angles at best. Despite these current labor- intensive methods for paste-like tailings disposal, it remains much cheaper to produce and dispose of paste tailings when compared to filtered tailings. Moreover, paste tailings disposal methods can still achieve water ratios of 0.3 - 0.4 m ³ /tonne, thus saving costs on filtration. In any event, it is generally much more difficult to transport and deposit paste-like tailings at the TSF than dried (cake) filtered tailings. FIGS. 1-4 depict the state of the art in the way of paste tailings management solutions. Turning now to FIG. 1, a conventional paste tailings disposal system 200 involves means for tailings deposition (i.e. , a tailings deposition technology) which is configured for creating a tailings pond 201. The tailings pond 201 is retained by a tailings dam 202. A collection pond 203 (where a majority of water may be stored) is located downhill of the tailings dam 202. A runoff collection dam contains the contents of the collection pond 203. A mill 205 may be used in a processing circuit, where spent tailings are sent to a tailings dewatering process (e.g., typically thickening/sedimentation for paste tailings) prior to deposition.

Makeup water 206 may be delivered to the mill 205 for grinding and other processes. This makeup water 206 may be reduced through the use of recycle water 207 taken from the collection pond 204. Some of the contents of collection pond 203 may be processed via a suitable water treatment solution and may ultimately discharged as effluent 208 or recycled to form a part of makeup water 206. In FIG. 1 , the bold dotted line 209 represents movement or flow path(s) of non-contact water, the lightweight dashed line 210 represents movement or flow path(s) of contact water, and the solid line 211 represents movement or flow path(s) of paste tailings coming from the mill 205.

FIG. 2 suggests one conventional tailings deposition technology according to the prior art. In this figure, it is being shown that paste tailings 211 are delivered to a pipe 213 or nozzle and discharged to the TSF/tailings pond 201 in rudimentary fashion. The pipe 213 may be provided to a fixed or movable pipe stand 212. Pipes 213 and/or pipe stands 213 may be relocated around the TSF periodically. Such low-tech solutions are generally labor-intensive, involve plenty of oversight/monitoring, and can pose safety hazards to personnel and equipment due to increased exposure and time spent on the TSF.

FIGS. 3 & 4 illustrate additional problems that can occur with such conventional tailings deposition technology employed to date. Adjacent the paste tailings discharge point 216 to the TSF, a plunge pool 217 may form. Due to terrain, geographic features, or anomalies in the TSF, one or more channels 214 may form before the tailings spread out in a fan 215 formation. A number of hydraulic jumps 218 may be present within a channel 214.

Though filtered (i.e. , cake-like or non-paste) dewatered tailings may improve stackability and avoid some of the aforementioned problems in the TSF that are associated with paste-like disposal, large capacity tailings filtration circuits require high energy inputs (i.e., high OPEX) to run, and also require large filtration equipment (i.e., high CAPEX & increased plant footprint). Moreover, tailings leaving the mill 205 having high concentrations of fines can present a number of challenges with traditional filtering methods (e.g., filter cloth blinding, large cycle times, etc.).

Accordingly, it would be desirable to provide a paste tailings disposal system, and method that lends itself to the efficiency of circumventing the need for filtering tailings, but which is less labor intensive than traditional paste tailings disposal methods. It would also be desirable to improve safety and reduce exposure to personnel and equipment within the TSF. It would further be desirable to provide a paste tailings disposal system/method which provides an option to dispose tailings at higher beach slope angles than what is currently possible by manually moving/shifting conventional pipe 213 and nozzle-type discharges.

Embodiments of the present invention aim to improve upon existing systems, apparatus, and methods by incorporating robust, low-cost structures which can more economically dispose of paste tailings from thickening/sedimentation processes at a fraction of the cost of filter-dewatered tailings. Such embodiments may employ sophisticated automation to enjoy further benefits.

OBJECTS OF THE INVENTION

It is an aim that embodiments of the invention provide an improved paste tailings disposal system & method which overcomes or ameliorates one or more of the disadvantages or problems described above, or, which at least provides a useful alternative to related conventional apparatus used within the art. For example, an aim of some embodiments of the invention may include providing improved paste tailings disposal system and method, or apparatus thereof, which exhibits the ability to operate at higher beach slope angles, for example beach slope angles above 3 degrees (and as much as 5-6 degrees from horizontal), without limitation.

Another aim of some embodiments of the invention may include providing an improved paste tailings disposal system and method, or apparatus thereof, which produces more even and uniform pond distributions (i.e., “thin lifts”), thus offering improved geostability, easier reclamation, and increased paste tailings material drying opportunities, without limitation.

Yet another aim of some embodiments of the invention may include providing an improved paste tailings disposal system and method, or apparatus thereof, which demands little manual intervention or which doesn’t require placing personnel or equipment in precarious TSF environments, without limitation.

Yet another aim of some embodiments of the invention may include lowering overall OPEX/CAPEX for placement of paste-like material as compared to current technologies and methods; whilst still achieving good water recovery with improved tailings safety.

Yet another aim of some embodiments of the invention may include achieving a better overall management of paste flow shape(s), less channelling, improved thin layer deposition schemes (TLDS) with drying cycles (DC), an increased promotion of sheet flows, higher beach slope operation angles, and/or lower energy losses, without limitation. Yet another aim of some embodiments of the invention may include providing low complexity, highly efficient paste tailings disposal apparatus (i.e., screw pontoon drives for a paste spreader) which are better configured for traction and/or supporting and distributing loads in wet paste tailings pond environments - with the added advantage of disrupting top surfaces to increase pond upper surface area exposed to air and sunlight, thus, further increasing drying opportunities for deposited paste tailings within the TSF. It should be understood that not every embodiment may be configured to obtain each and every one of the abovementioned objects. However, specific embodiments may demonstrate the ability to achieve or satisfy at least one or more of the abovementioned goals. Other preferred objects of the present invention will become apparent from the following description.

SUMMARY OF INVENTION

According to embodiments of the invention, a paste tailings disposal system (1) is disclosed. The paste tailings disposal system (1) may comprise a paste spreader (7). The paste spreader (7) may be configured for use within the paste tailings disposal system (1). It may be further configured to deposit paste tailings to a tailings storage facility (8).

In preferred embodiments, the paste spreader (7) may comprise a proximal end (27) and a distal end (28). A bridge (25) may be further provided to the paste spreader (7). The bridge (25) may have a tail section (22) adjacent the proximal end (27). The bridge (25) may have a head section (24) adjacent the distal end

(27). The bridge (25) may have an intermediate section between the tail (22) and head (24) sections.

A pipe (26) may be supported by and extend along the bridge (25). The pipe may be configured for receiving and conveying the paste tailings to the tailings storage facility (8). A plurality of nozzles (11 ) may extend from the pipe at discrete locations along the pipe (26). Each of the nozzles (11) may be configured to transfer the paste tailings from the pipe (26) to the tailings storage facility (8) at said discrete locations along the pipe (26). At least one automated valve (29) may be employed by the paste spreader (7). The at least one automated valve (29) may be configured to control flow through at least one of the plurality of nozzles (11), without limtiation.

In some embodiments, the paste spreader (7) may comprise a conveyor (30). The conveyor (30) may be supported by the bridge (25). The conveyor (30) may span a distance between the proximal (27) and distal ends (28) and may be configured for receiving and delivering material which is separate from the paste tailings. This material transported by the conveyor (30) may be used for building a tailings dam (4) - or, in some circumstances, be configured with a tripper for delivering drier tailings to the tailings storage facility (8) in conjunction with or in lieu of the paste tailings. Thus, in addition to delivering paste tailings to the TSF (8), the paste spreader (7) may also be configured to form (i.e. , build, manufacture, or reinforce) the tailings dam (4), without limtiation.

The paste spreader (7) may, in some preferred embodiments, comprise at least one floating screw pontoon (20) which may be operably driven by a screw pontoon drive (31). The at least one floating screw pontoon (20) and screw pontoon drive (31) may be operably configured to support and/or move a portion of the bridge (25) adjacent thereto. Movement may occur in one or more directions, including, but not limited to: longitudinal movement along a longitudinal axis of the bridge (25), transverse movement (i.e., translation) in a direction substantially perpendicular to the longitudinal axis of the bridge (25), rotation of the bridge (25) about a fixed point (e.g., about the proximal end (27)), general rotation of the bridge (25) or section thereof in relation to the longitudinal axis of the bridge (25), or a combination thereof, without limitation. A belt, chain drive, or transmission may be provided between a floating screw pontoon (20) and a screw pontoon drive (31 ) to transfer torque and power therebetween.

In some preferred embodiments, the floating screw pontoon (20) and the screw pontoon drive (31) may be located on at least the head section (24) or adjacent the distal end (28). In some embodiments, at least one crawler track (18) supporting the bridge (25) and being operably configured to support and move a portion of the bridge (25) adjacent thereto may be provided to the paste spreader (7). For example, the at least one crawler track (18) may be located on at least the tail section (22) or adjacent the proximal end (28).

The bridge (25) may comprise a plurality of bridge sections, without limitation. In such instances, at least one bridge section joint (12) may be provided between each of the bridge sections to effect bridge (25) articulation. The pipe (26) may comprise at least one flexible pipe connection (19) between each of the bridge sections. In this regard, the pipe (26) may be configured to accommodate bridge articulation of the bridge.

The paste spreader (7) may be configured to operate at beach slope angles or tailings storage facility (8) inclination angles which are above 3 degrees, for example, 3-6 degrees. In any event, it is preferred (for safety) that the paste spreader (7) operate in configurations within 6 degrees from horizontal.

The paste spreader (7) may be configured to pivot in a circular movement about a central point, adjacent a handoff junction (9) as depicted in FIG. 6. The paste spreader (7) a handoff junction (9) can be provided at an end of system feed conveyor (2) as depicted in FIG. 6. The paste spreader (7) may be configured to translate laterally, for example, in a direction substantially perpendicular to the bridge (25) as depicted in FIG. 5, without limtiation.

The paste spreader (7) may be configured to receive material for building a tailings dam (4) adjacent its proximal end (27). For example, the paste spreader (7) may be configured to receive material for building a tailings dam (4) from a system feed conveyor (2) as depicted in FIG. 6. Or, the paste spreader (7) may be configured to receive the dam (4)-building material from a tripper conveyor (3) being fed by a system feed conveyor (2) as depicted in FIG. 5, without limitation.

The paste spreader (7), in some instances, may comprise a plurality of pipes (26) having nozzles (11 ), without limitation. A plurality of pipes (26) may help maximize paste throughput or avoid the need to provide a large diameter pipe (26) to the paste spreader (7).

In some embodiments, the paste spreader (7) may comprise an end tripper (21) adjacent the distal end (28) on the head section (24), without limtiation. In some embodiments, the paste spreader (7) may comprise an E-house, a transformer, and/or an operations cab (13) adjacent the proximal end (27) on the tail section (22), without limitation.

A paste tailings disposal system (1) for a tailings storage facility (8) may comprise such a paste spreader (7) as described above. Moreover, a method for disposing paste tailings to a tailings storage facility (8) may be practiced. In its most basic form, the method may comprise the step of providing a paste spreader (7) as described above. The method may involve feeding paste tailings to the pipe (26). The method may involve adjusting an automated valve (29). In any event, the method would comprise the step of discharging the paste tailings from the pipe

(26) using at least one of the plurality of nozzles (11 ). It should be understood that more complex method steps will become inherent from the accompanying disclosure. For example, a step of adjusting multiple automated valves (29) to distribute flows to different ones of the nozzles (11) is anticipated. Flow at each nozzle (11 ) can be optimized at a given point in time based on bridge (25) or local bridge section movements, speeds, or location within the TSF (8). It would be expected that nozzles (11 ) that are at higher elevations, closer to the proximal end

(27), and/or moving at a slower rate of speed would discharge paste tailings from the pipe (26) at a reduced flow as compared to a nozzle(s) which is at a lower elevation, closer to the distal end (27), and/or moving at a relatively higher rate of speed.

Further features and advantages of the present invention will become apparent from the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

By way of example only, preferred embodiments of the invention will be described more fully hereinafter with reference to the accompanying figures. It will be appreciated from the drawings that some of the figures may intentionally omit features or hide components for clarity and/or better visualization and understanding of the invention. Moreover, for clarity, where there are a plurality of similar features in a particular figure, only one of the features may be labelled with respective reference numerals.

FIG. 1 depicts a traditional paste tailings system 200. The tailings deposition technology depicted may be enhanced by or replaced with embodiments of the invention, though the intention of FIG. 1 is to prove context to what has been done in the past in reference to FIGS. 2 - 4.

FIG. 2 is a photograph depicting typical paste tailings discharge according to prior art methods. FIG. 3 is a photograph depicting typical paste tailings discharge channelling and fanning according to prior art methods.

FIG. 4 is a diagram which schematically depicts the channelling and fanning occurring in the photo of FIG. 3.

FIG. 5 suggests one embodiment of a system 1 and associated apparatus 2, 3, 7, 9 for disposing of paste tailings accordance with the invention.

FIG. 6 suggests another embodiment of a system 1 and associated apparatus 2, 7, 9 for disposing of paste tailings in accordance with the invention.

FIG. 7 is a side plan view of a paste spreader 7 according to preferred embodiments, which may be employed in the systems 1 shown in FIGS. 5 & 6, without limitation. FIG. 8 is a side plan view of a tail section 22 of the paste spreader 7 depicted in FIG. 7, in operation. FIG. 9 is a side plan view of an intermediate section 23 of the paste spreader 7 depicted in FIG. 7, in operation.

FIG. 10 is a side plan view of a head section 24 of the paste spreader 7 depicted in FIG. 7, in operation.

FIG. 11 is a longitudinal cross-sectional view of the paste spreader 7 depicted in FIG. 7.

FIG. 12 is a top partial view of the paste spreader 7 depicted in FIG. 7.

The depictions of embodiments in FIGS. 5-12 are not intended to be limiting. Rather, they aim to suggest one or more preferred mode of many possible embodiments which can be drawn from this disclosure. DETAILED DESCRIPTION OF THE DRAWINGS

A paste tailings disposal system 1, apparatus, and method is disclosed. Embodiments disclosed herein may be configured similarly to a conventional mobile spreader and stacker (e.g., FLSmidth® brand Mobile Stacking Conveyor (MSC)) - except in that embodiments of the invention may be characterised in that they incorporate a unique, novel, and heretofore unobvious paste spreader 7 comprising at least one pipe 26 (rather than a conveyor belt) running along a length of a bridge 25. The pipe 26 is suitably configured to convey paste-like tailings material of various compositions and/or viscosities down the length of the bridge

25.

At predetermined locations along the pipe 26, embodiments may incorporate nozzles 11 attached to, extending from, and/or fluidly communicating with the pipe 26. The nozzles 11 may be advantageously configured and utilized to discharge paste tailings from the pipe 26 at discrete locations along the bridge 25, in a similar fashion to irrigation systems discharge water to fields (albeit with more specially- configured hardware and equipment). Here, the nozzles 11 are configured to deposit the paste tailings material onto the TSF 8, instead of a tripper which is typically employed with conventional mobile spreaders and stackers for discharging dry (cake) filtered tailings material. Each nozzle 11 may be controlled or manipulated (machine automated or manually), e.g., via automated valves 29, to dispose the correct amount(s) of paste tailings to the TSF depending on surface conditions of the TSF, weather, or feed material composition, without limitation. For example an automated valve 29 may control the discharge of paste-like tailings from pipe 26 through its respective nozzle, or, through a set of respective nozzles 11 (e.g., local adjacent nozzles 11 which share a single automated valve 29).

Depending on sheet flows, thin lift integrity, apparatus configurations, area(s) sought for disposal, drying cycle times, sheet thickness, path of apparatus travel, and/or rate of movements of the apparatus 7 or segments thereof over time, flow through each of the nozzles 11 can be independently set or adjusted over time to optimize coverage of the TSF 8, improve uniformity in paste distributions, and/or increase the drying time of the disposed paste-like tailings. It should be understood that while not ideal, in lieu of nozzles 11 , less sophisticated porting features such as openings, flow orifices, static (i.e. , non-adjustable) nozzles, and perforations in the pipe may be alternatively employed to the pipe for adequate paste tailings distribution to the TSF 8 from pipe 26.

As will be further appreciated hereinafter, embodiments may involve the inventive concept of providing a Mobile Stacking Conveyor (MSC)-type machine which is much more adequately configured to deposit paste-like tailings into a tailings storage facility (TSF) 8. Such a machine (i.e., “paste spreader” 7) may utilize screw pontoon drives 31 controlling floating screw pontoons 20 (instead of, or in addition to traditional MSC crawler tracks 18) to navigate across the TSF 8 and make even deposits of paste tailings on its way. As suggested from the figures, it is anticipated that one or more floating screw pontoons 20 or sets of floating screw pontoons 20 may be preferably provided to the paste spreader 7 at intermediate sections 23 and/or adjacent head 24 portions of the bridge 25, such as adjacent a distal end 28 of the paste spreader. More conventional crawler tracks 18 may be preferably provided to portions or sections the paste spreader 7 which are more adjacent a tail portion 22 of the bridge 25, e.g., closer to a proximal end 27 of the paste spreader 7, without limitation.

Embodiments described herein may be provided through 3 modes. A first mode may involve a paste spreader bridge 25 (only) mode, wherein the described paste spreader 7 deposits the paste tailings within the TSF 8 via one or more pipes 26 and nozzles 11. A second mode may involve a paste spreader bridge 25, with the one or more pipes 26, in combination with a conveyor 30 running along the length of the bridge, and a boom conveyor or tripper 21 located at the distal (head) end 28 of the paste spreader 7. In this second mode, the idea is to use the pipe 26 of the paste spreader 7 to deposit the paste tails to the TSF 8, and use the separate (parallel-running) conveyor 30 to build a retaining dam 4 at the edge of the TSF 8. Thus, this second mode may provide a paste spreader 7 with an option of dual functionality. A third mode may involve a paste spreader bridge 25 having a conveyor 30 running along the length of the bridge 25, and tripper (not shown) configured to traverse along the length of the conveyor 30. In this third mode, a pipe 26 may or may not be present.

Depending on the properties (e.g., dryness) of the paste being deposited at any given time, this third option may be used to convey the paste, and dump it off various locations of the bridge 25 in a more conventional fashion, rather than pump it through a pipe 26. It should be understood, that this third mode embodiment may involve bridges 25 that are equipped with or without a pipe 26 for disposing of paste tailings, without limitation.

This third mode may, for example, in instances where multiple paste spreaders 7 are employed to the TSF 8 within the system 1 (e.g., more than one paste spreader 7 in the configurations seen in FIGS. 5 &/or 6), incorporate some paste spreaders 7 provided with a pipe 26, some paste spreaders 7 configured with a conveyor 30 and tripper (not shown) and devoid of a pipe 26 for paste transport, and/or some paste spreaders 7 that are equipped with both a pipe 26 and a conveyor 30, without limitation.

FIG. 5 depicts one embodiment involving a mode of, or configuration for, longitudinal movement of a paste spreader 7 within the TSF 8, without limitation. As depicted, optional radial movement at ends of travel may be employed to maximize TSF 8 area/coverage. In such embodiments, the paste spreader 7 may traverse along a tripper conveyor 3 in a direction substantially orthogonal or transverse to a longitudinal axis of its bridge 25. The tripper conveyor 3 is configured to feed paste tailings to the paste spreader 7 via a handoff junction 9. The tripper conveyor 3 may receive paste tailings and/or dam-building material as feed from a system feed conveyor 2. A distal end 28 of the paste spreader 7 may be located downhill in direction 6 adjacent the tailings dam 4. The tailings dam 4 may sit just above a runoff water collection pond/dam 5 as suggested in FIG. 1. At limit ends of the tripper conveyor 3, the paste spreader 7 may optionally swing in an arcuate path of travel (i.e. , rotational or pivoting movement) as shown.

FIG. 6 depicts an alternative embodiment involving another representative mode of, or configuration for radial or pivotal (only) movement of the paste spreader 7 within the TSF 8. As shown, a system feed conveyor 2 may feed paste tailings to a pivoting paste spreader 7. While not shown, the system feed conveyor 2 could equally be an extension of the tripper conveyor 3 shown in FIG. 5. The handoff junction 9 may comprise a swivel joint, flexible hose, feed hopper, slurry transport mechanism, paste feed system 16, or the like to convey paste tailings from the system feed conveyor 2 to a pipe 26 of the paste spreader 7. The handoff junction 9 may also comprise means for handing off material to the paste spreader 7 for building the tailings dam 4. The central pivot arrangement shown allows the paste spreader 7 to move clockwise or counterclockwise about the TSF 8, while being fed at a single proximal location. Though FIG. 6 is a top plan view, it should be appreciated that the TSF 8 may comprise a downwardly sloping beach slope angle between the handoff 9 and the surrounding tailings dam 4. Said differently, the TSF 8 shown in FIG. 6 may be anywhere from planar to conical in elevation, without limitation.

FIG. 7 depicts a non-limiting embodiment of a paste spreader 7 shown in side plan view. The paste spreader 7 may be operationally configured to work at higher- than-conventional beach slope angles 10, for example, within a +-6 degree beach slope angle, without limitation. The paste spreader 7 may comprise a bridge 25 and proximal 27 and distal 28 ends as shown. The bridge 25 may comprise one or more paste pipes 26 which are configured to evenly or non-uniform ly distribute paste tailings to the TSF 8 as required. The bridge 25 may support the one or more pipes 26 using connection means therebetween.

A tail section 22 of the paste spreader 7 may be fed by a system feed conveyor 2, a tripper conveyor 3, or a waste rock conveyor 15. A rail-mounted tripper 14 may be used to facilitate this handing over of the material to the paste spreader 7, without limitation. The tail section 22 may comprise an electronics house (Έ- house”), transformer, &/or operations cab 13. The tail section 22 may comprise a conveyor drive and take-up 17 for a conveyor 30 supported by the bridge 25 (for embodiments where a conveyor 30 is employed). The tail section 22 may comprise one or more support drives, such as crawler tracks 18 to support and move the bridge 25; however, it may alternatively (or additionally) comprise one or more screw pontoon drives 31 which are configured to propel one or more floating screw pontoons 20. More traditional crawler tracks 18 may be desirable closer to the proximal end 27 of the paste spreader 7 to support the added loads of the take- up 17, E-house, transformer, and/or operations cab 13.

The tripper 14 may be used to feed dam-building material to a conveyor 30 supported by the bridge 25. The conveyor 30 may be adapted to convey the same to an end tripper 21 for facilitating the manufacturing of tailings dam 4. The end tripper 21 may be configured with a slewing cross-conveyor, without limitation.

The tail section 22 of the paste spreader 7 may comprise a paste feed system 16. The paste feed system 16 may comprise equipment such as a pump, control valve(s), emergency shutoff valve(s), etc. The paste feed system 16 may be configured for moving paste tailings through the one or more pipes 26. The paste feed system 16 may be configured for connecting the one or more distribution pipes 26 of the paste spreader 7 to a mill or plant paste tailings discharge mainline.

In some embodiments, the tripper 14 at the handoff junction 9 may be configured to form a portion of the paste feed system 16. In this regard, the tripper may, in some embodiments, be dually configured or otherwise adapted to supply paste tailings to one or more pipes 26 in the paste spreader 7 in addition to supplying material used for building the tailings dam 4 along the periphery of the TSF 8. For example, a coupling (e.g., swivel flange, hose, or equivalent flexible pipe connection) may be provided to or extend from the tripper 14 for simultaneously or alternatively feeding a pipe 26 of the paste spreader 7.

A plurality of paste nozzles 11 may be provided to each of said one or more pipes 26. The nozzles 11 may serve to evenly distribute the paste tailings across the TSF 8. In some embodiments, the flow through each nozzle 11 may be different depending on its location within the paste spreader. For example, in some embodiments, nozzles 11 may be adjusted so that more distally-located nozzles 11 , within the head section 24 may have a higher throughput than more proximally- located nozzles 11 (e.g., those within the tail section 22), without limitation.

Material (e.g., paste and/or dam building material) may flow along the paste spreader from the proximal end 27 of the paste spreader 7 towards the distal end 28 of the paste spreader 7 in the direction depicted by arrow 33. One or more bridge section joints 12 may be provided to the bridge 25 to allow for some bridge articulation in any direction. For example, these bridge section joints 12 may help the paste spreader accommodate variations in beach slope angle throughout the TSF 8. One or more flexible pipe connections 19 may be provided between sections of pipe 26 to accommodate bridge 25 articulation, without limitation.

The paste spreader 7 may, in addition to the tail section 22, comprise an intermediate 23 section and a head section 24. The head section 24 preferably comprises one or more floating screw pontoons 20 and drives 31. If provided to the paste spreader 7, the end tripper 21 may be located on the head section 24 of the paste spreader 7, e.g., at or adjacent the distal end 28 of the bridge 25 and conveyor 30.

FIG. 8 shows a tail section 22 of a paste spreader 7 in use, according to some non limiting embodiments. As shown, the paste spreader 7 may be fed by a mobile overland tripper 14 on rails, without limitation. Crawler tracks 18, support skids, and/or the like on the tail section 22 of the bridge may be advantageously employed in order to accommodate the additional loads of feeding equipment, E- house, transformer, &/or operations cab 13. Multiple conveyors may be used to feed the paste spreader 7. A dedicated paste conveyor or paste mainline (not clearly depicted) may serve to feed the one or more paste tailings conveyance pipes 26, and a waste rock conveyor 15 may be employed to feed conveyor 30 for building the retaining dam 4, without limitation.

FIG. 9 shows a paste spreader arrangement/operation at its intermediate section 23. One or more screw pontoons may be provided at ends of each articulating bridge section forming the bridge 25. To allow for bridge 25 articulation, flexible pipe connections 19 may be provided to the paste pipes 26 adjacent each bridge section junction. Along the length of the bridge 25, paste spreading nozzles 11 may be staggered (preferably evenly spaced from one another), with automated control valves 29 to control flows of paste tailings material therethrough. In some preferred embodiments, each section of the bridge 25 may be configured to be coupled to another section of the bridge 25, uncoupled from other sections of the bridge 25, and/or maneuver independently relative to other sections of the bridge 25, without limitation. End segments of pipe 26 from disjointed bridge segment may be configured such that they may be connected to each other.

FIG. 10 shows a head section 24 of a paste spreader 7 arrangement according to practical embodiments. The head section 24 may be largely configured in a manner similar to the intermediate section(s) of the paste spreader 7, with the exception that a stationary end tripper 21 may be preferably provided to the distal end 28 of the bridge 25. The end tripper 21 may be equipped with a slewing and tilting boom conveyor at the end of the last (i.e. , distal-most) bridge section. The same may be configured to be used to build up the retaining dam 4 during system 1 operations within the TSF 8.

Challenges with operation of the system 1 may include, without limitation: keeping the paste spreader 7 aligned with the feeding tripper 14, avoiding downhill sliding of the paste spreader, keeping independent sections of the bridge 25 (if present) sufficiently aligned in the 3 axes, operating the system 1 and each paste spreader 7 within the system 1 such that rollover does not occur with a mobile tripper on the conveyor belt 30 (e.g., end tripper 21), and/or reducing dynamic point loads associated with a mobile tripper (e.g., end tripper 21).

FIGS. 11 and 12 depict more detailed views of the aforementioned screw pontoon drives 31 , and suggest several automated movement controls which are designed to more efficiently propel the paste spreader 7 laterally (i.e., perpendicular to the bridge 25), longitudinally (i.e., parallel to the bridge 25), and/or radially (i.e., pivoting around the feed point or clockwise/counter-clockwise in relation to a longitudinal axis of the bridge 25).

It will become apparent to those skilled in the art that alternative paste spreader 7 embodiments and system 1 configurations may be anticipated by or derived from the teachings found in the present disclosure. For example, variations and/or adaptations may be made to the proffered paste spreader embodiments when taking into consideration local personnel, machine, and operational safety requirements. Moreover, variations and/or adaptations may be made to the proffered paste spreader embodiments - especially when taking into consideration, bridge loads which are unique to a particular system 1 for paste tailings disposal. Operational conditions (as it relates to composition of paste tailings and water content of paste) need to be considered when configuring a paste spreader 7 so that the apparatus does not sink into or have an increased vulnerability of becoming lodged in deposited paste tailings. Screw pontoon drive 31 and float 20 placement may need to be altered from what is shown, and more or less screw pontoon drives may be required or employed from what is shown.

Additionally, variations and/or adaptations may be made to the proffered paste spreader 7 embodiments when taking into consideration, the type, velocity, viscocity, water content, flow rate, and/or material composition(s) of the feeding paste being provided to the paste spreader (whether pumped or conveyed). Different applications may require different outfitting of paste spreaders 7.

It should further be appreciated that modifications to the proffered paste spreader 7 embodiments may be made, depending on whether or not duel-feeding (i.e. , with paste and dam material) is being or is to be employed in a particular paste tailings disposal operation. Lastly, it should be understood that the power distribution to each independently-controlled screw pontoon drive 31 may be optimized or changed over time, based on current or local loading/loads; the radial, angular, or linear distance to be travelled at discrete bridge 25 locations, and/or local composition or dryness of paste tailings (earth) supporting various sections of the paste spreader 7 along the bridge 25 and/or underneath screw pontoons 20. Accordingly, some screw pontoon drives (e.g., those located more adjacent to distal 28 portions of bridge or over ‘wetter’ paste tailings) may require more power than others (e.g., those pontoons 20 located adjacent more proximal or intermediate portions of bridge or over drier paste tailings), without limitation.

It should be further noted that the floating screw pontoons 20 described herein may be constructed using various outer flights, spiral/helical profiles, shapes, materials, etc. They may be provided as solid or hollow devices. Geometries thereof may be optimized for particular TSF 8 compositions and/or character.

The above description of the present invention is provided for purposes of description to one of ordinary skill in the related art. It is not intended to be exhaustive or to limit the invention to a single disclosed embodiment. As mentioned above, numerous alternatives and variations to the present invention will be apparent to those skilled in the art in light of the above teaching(s). Accordingly, while some alternative embodiments have been discussed specifically, other embodiments will be apparent or relatively easily developed by those of ordinary skill in the art. The invention is intended to embrace all alternatives, modifications, and variations of the present invention that have been discussed herein, as well as other embodiments that might clearly fall within the spirit and scope of the above described invention.

In this specification, the terms ‘comprises’, ‘comprising’, ‘includes’, ‘including’, ‘having’ or similar terms are intended to mean a non-exclusive inclusion, such that a method, system or apparatus having an inclusion of a list of elements may not necessarily include those elements solely, but may also include other elements not listed. For example, a paste tailings disposal system/apparatus/method described herein may or may not comprise certain features or elements discussed herein.

Where described herein, and in the appended claims, the terms “paste tailings disposal apparatus,” “paste tailings disposal system”, and “paste spreader” may be used synonymously and/or interchangeably, without limitation.

LIST OF REFERENCE IDENTIFIERS

1 Paste tailings disposal system

2 System feed conveyor(s)

3 Tripper conveyor(s)

4 Paste retaining dam

5 Runoff water collection pond/dam

6 Direction of decreasing (natural) slope which forms beach slope angle

7 Paste spreader/paste tailings disposal apparatus

8 Tailings storage facility (TSF) (e.g., paste tailings pond, paste tailings)

9 Handoff junction (e.g., tripper/hopper or pivot)

10 Machine operational (beach slope) angle

11 Paste nozzles

12 Bridge section joint

13 E-house, Transformer, &/or Operations cab

14 Rail-mounted tripper

15 Waste rock conveyor

16 Paste feed system

17 Conveyor drive and take-up

18 Crawler tracks (optional)

19 One or more flexible pipe connections

20 Floating screw pontoon

21 End tripper with slewing cross conveyor

22 Tail section of paste spreader 7

23 Intermediate section of paste spreader 7

24 Head section of paste spreader 7

25 Bridge

26 Paste pipe(s) (for paste tailings transport to nozzles 11 )

27 Proximal end of paste spreader 7

28 Distal end of paste spreader 7

29 Automated valve

30 Conveyor

31 Floating screw pontoon drive(s)

32 Belt/chain drive or transmission 33 Direction of material flow

200 Conventional paste tailings disposal system

201 Tailings pond

202 Tailings dam 203 Collection pond (majority water storage)

204 Runoff collection dam

205 Mill

206 Makeup water

207 Recycle water 208 Discharge

209 Non-contact water

210 Contact water

211 Paste tailings

212 Conventional pipe stand 213 Conventional pipe

214 Channel

215 Fan

216 Discharge point

217 Plunge pool 218 Hydraulic jumps