WO2016191800A1

WO2016191800A1 - Underground mining system

Info

Publication number: WO2016191800A1
Application number: PCT/AU2016/000192
Authority: WO
Inventors: Alexander Hamilton Lewis-Gray
Original assignee: Gekko Systems Pty Ltd
Priority date: 2015-06-05
Filing date: 2016-06-03
Publication date: 2016-12-08

Abstract

A mining system that includes at least one remote mining head assembly that is capable of mining a seam of ore and tracking the direction of the seam of ore. The assembly uses high intensity electrical pulse electrodes to dislodge and break up the material at the end of a mine shaft, and also includes logic control means, proximity and chemical analysis sensors to control the direction of the mining head assembly and to keep the electrodes at the optima distance from the end of the mine shaft. The assembly also includes means to flood the cavity forward of the mining head so that the dislodged material is incorporated into the water to form a slurry. The slurry is then withdrawn through a screen and carried away to a separate ore processing facility. Material that is too large to pass through the screen is further broken down under the action of the electrodes until it becomes sufficiently small. The assembly also includes lining means that creates a durable and relatively smooth lining on the trailing walls of the mine shaft.

Description

Underground Mining System

Field of the Invention This invention relates to an underground mining system where the mining apparatus is able to track the seam of the ore being mined.

Background of the Invention In many mining operations, the ore that is being mined is not evenly distributed in any unit volume of material. For example, in a sample 10 cubic meter quantity of earth, the ore may be concentrated in the center of the volume, and the rest of the volume is valueless overburden. Quite often ore runs in long underground seams. It is often difficult to accurately determine the direction of the seam at any location within the unit volume of earth being mined.

Often the only economical way to remove the ore from the unit volume of earth is to remove the entire volume of earth, then crush it all up, and then pass it through a separator to separate the ore from the overburden and gangue. This approach is effective, as it ensures that the maximum yield of ore is derived from any processed volume of earth, however much of the heavy equipment used to process the volume of earth removed is often expensive to run, either in power or consumables such as water etc. They are often expensive to maintain, and the ongoing commercial viability of their continued operation are very susceptible to any significant downward movement of the ore price on the commodities market due to all the worthless processing of the over burden and gangue.

It is a goal of the present invention to ameliorate at least some of the aforementioned problems. Disclosure of the Invention

Accordingly, the present invention is a remote mining head assembly for a mining system that operates within a mine shaft, including:

- an elongate body having a forward face, and

a screen, and

a plurality of electrodes, and

a water outlet, and

an inflow water conduit, and

- a slurry inlet, and

an slurry outflow conduit, and

- propulsion means, wherein the elongate body has a circular cross-section. The plurality of electrodes are located on the forward face, substantially around the outer peripheiy of the forward face, and it is the operation of the electrodes on the material being mined that causes portions of that material to break away. The screen is located in the central region of the forward face, and the inflow water conduit passes through the elongate body, and the water outlet is located on the forward face behind the screen. The slurry outflow conduit also passes through the elongate body, and the slurry inlet is also located behind the screen. The apertures in the screen are appropriately sized to suit the size of the solid material that is broken away by the operation of the electrodes and subsequently entrained in the slurry. The propulsion means are adapted to move the remote mining head forward within the mine shaft so that the electrodes are kept at an optimal distance from the material being mined.

Preferably, the assembly includes lining and sealing means that are adapted to create a trailing lining on the wall of the mine shaft as the remote mining head is progressed forward.

Preferably, the assembly includes trailing control signal, data and electricity cables, that trail behind the assembly, which supply electrical power, command and control signals, and other signals, including telemetry, to and from the assembly. Preferably, the assembly includes logic control means that interact with operators and equipment above ground via at least the trailing control signal and data cables.

Preferably, the assembly includes an array of sensors that are located in an array around the sidewall, and sends the data collected by the sensor to the logic control means so that the logic control means can control the operation of the propulsion means to thereby keep the electrodes at an optimal position, relative to the material being mined.

Preferably, the assembly includes barrier means that are located behind the array of sensors and substantially prevent any flow of fluid rearward of the barrier.

Preferably, wherein a void is established and maintained between the forward face of the remote mining head and the material it is mining, and the supply of water is turned on so that it flows through the water inflow conduit and out into the void via the water outlet, and floods the void.

Preferably, the plurality of electrodes pulse discharge with sufficient frequency, voltage, and current, to cause the material in its vicinity to fragment, and as the material is fragmented, the fragmented pieces of fragmented material mix with the flow of water to create the slurry, and the slurry is continuously withdrawn from the void, through the screen, and into the slurry inlet, where the slurry is carried through the slurry outflow conduit to a trailing ore processing plant.

Preferably, wherein the inflow of water and the outflow of the slurry are controlled to ensure the void is replenished with fresh water as the slurry is removed from the void during operation of the mining head.

Preferably, the array of sensors is capable of determining the chemical composition of the material in the vicinity of the forward face of the mining head assembly, and this information is fed back to the logic control means to assist in determining the direction that the remote mining head moves, so that the mining head can track along a particular seam of ore. Preferably, as the assembly moves forward, it trails behind a rough tunnel, and the lining and sealing means continuously produces a viscous paste of material that is deposited onto the sidewall of the tunnel, and tamping means are included, to continuously tamp the paste against the rough tunnel sidewall to ensure that the paste is adequately keyed onto the sidewall.

Preferably, the viscous paste has the property that it rapidly solidifies soon after being applied to the wall, thereby creating a solid, resilient, smooth lining with a substantially uniform internal diameter, that the propulsion means are able to drive along to push the head assembly forward or backwards, as required, to maintain an optimum distance between the electrodes and the material that the electrodes are operating on.

Preferably, a dedicated feeding conduit is included, that passes through the mining head assembly, and supplies a continuous feed of lining material derived from the slurry created by the operating of the mining head, to the lining and sealing means.

Preferably, the feed of lining material is separated out of the slurry, and the lining and sealing means is capable of using the separated material and turning it into a fast hardening viscous paste that is able to be deposited on the sidewall of the rough tunnel to create a lining that is both resilient and sufficiently smooth.

Preferably, the lining and sealing means is capable of melting the separated material and depositing it onto the sidewall, whereat it quickly solidifies when in contact with the relatively cold sidewall.

Preferably, the lining and sealing means is capable of mixing the separated material, and a suitable quick setting cement compound, such as an epoxy resin, into a paste, and the created paste is then applied to the sidewall of the rough tunnel. In another form, the present invention is a mining system including a plurality of separate mining head assemblies and each mining head assembly is capable of tracking a separate ore seam and returning its slurry to an ore processing facility that is capable of processing multiple slurry feeds simultaneously, and controlling the operation of the plurality of separate mining head assemblies simultaneously.

In another form, the present invention is a method of mining using a remote mining head assembly, where the remote mining head assembly having an elongate body that has a forward face, and an elongate body having a circular cross section, and a plurality of electrodes that are located on the forward face, and a screen that is located in the central region of the forward face. The size and number of apertures in the screen are selected to match the size, shape and type of material being mined. The assembly also includes an inflow water conduit that is capable of flooding the cavity substantially in front of the forward face, and the end of the hole, and barrier means, a slurry outflow conduit, and propulsion means that are capable of driving the remote mining head assembly in either a forward or backward direction, and an array of sensors on the forward face that feed there sensor signal data to a logic control means that performs command and control functionality for the remote mining head. The method including the steps of:

a creating a hole in a suitable location, and with a suitable diameter, at ground level, in the vicinity of the ore body that is to be mined, and

b inserting a length of conduit into the hole, so as to act as a starter lining for the propulsion system to engage with, and

C. using the array of sensors to positi on the electrodes at the optimum distance from the end of the hole, and

d flooding the cavity between the forward end of the remote mining head and the end of the hole via the inflow water conduit wherein the water is contained in the cavity via the barrier means, and

e operating the remote mining head assembly so that it uses an array of electrodes located on the forward face of the assembly to pulse discharge electrical current with sufficient frequency, voltage, and current, to cause the material in its vicinity at the end of the hole to fragment, and to thereby form a slurry, and

f. withdrawing the slurry from the cavity through the screen via the slurry outflow conduit, and then carried away from the remote mining head assembly to a separate ore processing plant, and g. the array of sensors is capable of analysing the chemical composition of the material in the vicinity of the forward face, and this information is then fed back to the logic control means and is used to steer the direction of the remote mining head so that it can track along a particular seam of ore. Preferably the remote mining head assembly used in the method of mining also includes lining and sealing means, and a lining and sealing means feed conduit. The method including the additional steps of:

a. drawing solid material from a controlled portion of the slurry into the lining and sealing means feed conduit, and

b. using the lining and sealing means to produce a viscous paste that incorporates the solid material and using that paste to line the sidewall of the mining shaft generated by the operation of the remote mining head assembly, so as to generate a relatively smooth and resilient trailing sidewall.

Preferably the method of mining further includes the steps of:

a. incorporating a quick setting cement, such as an epoxy resin, into the paste, so that when the generated smooth and resilient trailing sidewall solidifies quickly and controllably.

Alternatively, the method of mining further includes the steps of:

a. incorporating means to at least partially melt the drawn solid material, and apply that molten material to the sidewall whereat it quickly solidifies under the influence of the comparatively cold mine shaft sidewall.

Brief Description of the Drawings

Figure 1 is a cut-away side view of the remote mining head that is in accordance with the present invention. The cut line is the centre-line along the longitudinal axis of the body of the mining head. Detailed Description of the Preferred Embodiments

In Figure 1 we are shown a cut-away side view of the mining head assembly 1. The head unit 1 includes an elongate circular body. Located on the forward face 3 of the head assembly 1 is an array of electrodes 5. A screen 13 is provided in the centre region of the forward face 3. A cavity 7 is formed in the vicinity of the forward face 3. A water supply inflow conduit 9 provides water that is able to flow out of the water outlet 1 1 and flood the cavity with water. In this illustration of the invention, the water outlet is shown to be located on the sidewall of the mining head assembly 1. In another fonn of the invention, the water outlet 11 may be located behind the screen 13. On the periphery of the sidewall of the mining head assembly 1, in the vicinity of the forward face 3 is located an infra-red sensor array 15. Further back, along the sidewall of the mining head assembly 1 is the sealing and lining means 17. And further back from that along the length of the side-wall of the mining head assembly 1 is the propulsion means 19.

In use, water is pumped through the water inflow conduit 9 and out of the water outlet 1 1 so that the cavity 7 is flooded with water. The electrodes 5 emit a pulsed plasma that has a frequency and electrical intensity that is capable of breaking away the side- wall of the cavity 7. Particles of various sizes then become entrained in the water to fonn a slurry. Particles that are sufficiently small are able to pass through the screen 13 as the slurry is pumped out of the cavity 7 through a slurry outflow conduit 25. Particles that are too large to pass through the screen 13 continue to receive pulses of plasma from the electrodes, and therefore continue to break down into smaller and smaller particles within the fragmentation zone 27. The inflow of water into the cavity 7 is controlled to match the outflow of the slurry so that the cavity remains flooded while the mining head assembly 1 is in operation. As the material in the vicinity of the forward face 3 is fragmented, and propulsion means 19 pushes the mining head assembly forward. The effect of this is to create a tunnel.

The tunnel created typically has a rough side- wall. It is desirable to line this side-wall and to provide a tough and durable surface upon which the propulsion means is able to push against as it pushes the mining head assembly 1 along the tunnel, in either a forward or reverse direction. In one preferred embodiment, the sealing and lining means 17 is a 3D printing device. The 3D printing device is capable of producing a continuous flow of viscous paste that is applied to the sidewall and tamped to ensure it is forces into the rough side-wall of the tunnel 21. The viscous paste has the property of quick setting, and quickly solidifies into a resilient lining 23 with a comparatively smooth inner wall that the propulsion means 19 can drive along. The continuous lining operation delineates the boundary between the forward wet area of the cavi ty 7 and the comparatively dry area of the lined tunnel. The infra-red sensor array 15 is capable of conducting continuous, or semi-continuous chemical analysis of the material in the cavity wall in its vicinity. This analysis is capable of assisting in determining the directi on that the seam of ore takes underground. The information it produces is then fed back to the logic control means in the ore processing plant that can either move along behind the mining head assembly 1 , or can be stationary above ground. This information can then be used to control the direction of operation of the mining head assembly 1 so that it can accurately track the direction of the ore seam underground.

In another preferred embodiment of the invention, there can be a plurality of mining head assemblies that are connected to and controlled by a single trailing or stationary above ground ore processing plant. Each of the mining head assemblies 1 can be tracking a different portion of ore seam, and can therefore be moving and operating in a variety of different directions underground simultaneously. In another preferred embodiment, 3D scanning means are included that are capable of mapping the 3D shape of the cavity and determining any voids in the sidewall of either the cavity 7 or the tunnel 21. This information is fed back to the logic control means so that as each of the head(s) in the mining equipment operates underground, a detailed 3D map of the network of tunnels created is developed. The map then assists in navigating the direction of travel of the mining head assembly to ensure it is travelling along the preferred tunnel. It is also useful in determine where there may be a branch of the tunnel, and this can then help to control the lining sealing and lining means 17 to prevent it from attempting to line the void.

In another preferred embodiment, the outflow of water can be directed through the screen 13 to attempt to clear any screen blockages.

In another preferred embodiment, the feed for the sealing and lining means 17 may be obtained from a portion of finely fragmented particles that are generated by the operation of the electrodes 5.

While the above description includes the preferred embodiments of the invention, it is to be understood that many variations, alterations, modifications and/or additions may be introduced into the constructions and arrangements of parts previously described without departing from the essential features or the spirit or ambit of the inventi on.

It will be also understood that where the word "comprise", and variations such as "comprises" and "comprising", are used in this specification, unless the context requires otherwise such use is intended to imply the inclusion of a stated feature or features but is not to be taken as excluding the presence of other feature or features.

The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that such prior art forms part of the common general knowledge.

Claims

1. A remote mining head assembly for a mining system that operates within a mine shaft, including:

a. an elongate body having a forward face, and

b. a screen, and

c. a plurality of electrodes, and

d. a water outlet, and

e. an inflow water conduit, and

f. a slurry inlet, and

g- a slurry outflow conduit, and

h. propulsion means, wherein the elongate body has a circular cross-section, and the plurality of electrodes are located on the forward face, substantially around the outer periphery of the forward face, and it is the operation of the electrodes on the material being mined that causes portions of that material to break away, and wherein the screen is located in the central region of the forward face, and the inflow water conduit passes through the elongate body, and the water outlet is located on the forward face behind the screen, and wherein the slurry outflow conduit also passes through the elongate body, and the slurry inlet is also located behind the screen, and wherein the apertures in the screen are appropriately sized to suit the solid material that is broken away by the operation of the electrodes and subsequently entrained in the slurry, and wherein the propulsion means are adapted to move the remote mining head forward within the mine shaft so that the electrodes are kept at an optimal distance from the material being mined.

2. The remote mining head assembly as defined in claim 1 wherein the assembly includes lining and sealing means that are adapted to create a trailing lining on the wall of the mine shaft as the remote minin g head is progressed forward.

3. The remote mining head assembly as defined in claim 1 wherein the assembly includes trailing control signal, data and electricity cables, that trail behind the assembly, which supply electrical power, command and control signals, and other signals, including telemetry, to and from the assembly.

The remote mining head assembly as defined in claim 3 wherein the assembly includes logic control means that interact with operators and equipment above ground via at least the trailing control signal and data cables.

The remote mining head assembly as defined in claim 4 wherein the assembly includes an array of sensors that are located in an array around the sidewall, and sends the data collected by the sensor to the logic control means so that the logic control means can control the operation of the propul sion means to thereby keep the electrodes at an optimal position, relative to the material being mined.

The remote mining head assembly as defined in claim 5 wherein the assembly includes barrier means that are located behind the array of sensors and substantially prevent any flow of fluid rearward of the barrier.

The remote mining head assembly as defined in claim 1 wherein a void is established and maintained between the forward face of the remote mining head and the material it is mining, and the supply of water is turned on so that it flows through the water inflow conduit and out into the void via the water outlet, and floods the void.

8. The remote mining head assembly as defined in claim 7 wherein the plurality of electrodes pulse discharge with sufficient frequency, voltage, and current, to cause the material in its vicinity to fragment, and as the material is fragmented, the fragmented pieces of fragmented material mix with the flow of water to create the slurry, and the slurry is continuously withdrawn from the void, through the screen, and into the slurry inlet, where the slurry is carried through the slurry outflow conduit to a trailing ore processing plant.

9. The remote mining head assembly as defined in claim 7 wherein the inflow of water and the outflow of the slurry are controlled to ensure the void is replenished with fresh water as the slurry is removed from the void during operation of the mining head.

10. The remote mining head assembly as defined in claim 5 wherein the array of sensors is capabl e of determining the chem ical composition of the material in the vicinity of the forward face of the mining head assembly, and this information i s fed back to the logic control means to assist in determining the direction that the remote mining head moves, so that the mining head can track along a particular seam of ore.

1 1. The remote mining head assembly as defined in claim 2 wherein as the assembly moves forward, it trails behind a rough tunnel, and the lining and sealing means continuously produces a viscous paste of material that is deposited onto the sidewall of the tunnel, and tamping means are included, to continuously tamp the paste against the rough tunnel sidewall to ensure that the paste is adequately keyed onto the sidewall.

12. The remote mining head assembly as defined in claim 11 wherein the viscous paste has the property that it rapidly solidifies soon after being applied to the wall, thereby creating a solid, resilient, smooth lining with a substantially uniform internal diameter, that the propulsion means are able to drive along to push the head assembly forward or backwards, as required, to maintain an optimum distance between the electrodes and the material that the electrodes are operating on.

13. The remote mining head assembly as defined in claim 2, wherein a dedicated feeding conduit is included, that passes through the mining head assembly, and supplies a continuous feed of lining material derived from the slurry created by the operating of the mining head, to the lining and sealing means.

14. The remote mining head assembly as defined in claim 13 wherein the feed of lining material is separated out of the slurry, and the lining and sealing means is capable of using the separated material and turning it into a fast hardening viscous paste that is able to be deposited on the sidewall of the rough tunnel to create a lining that is both resilient and sufficiently smooth.

15. The remote mining head assembly as defined in claim 14, wherein the lining and sealing means is capable of melting the separated material and depositing it onto the sidewall, whereat it quickly solidifies when in contact with the relatively cold sidewall.

16. The remote mining head assembly as defined in claim 14, wherein the lining and sealing means is capable of mixing the separated material, and a suitable quick setting cement compound, such as an epoxy resin, into a paste, and the created paste is then applied to the sidewall of the rough tunnel.

17. A mining system including a plurality of separate mining head assemblies as previously defined in claim 1 wherein each mining head assembly is capable of tracking a separate ore seam and returning its slurry to an ore processing facility that is capable of processing multiple slurry feeds simultaneously, and controlling the operation of the plurality of separate mining head assemblies simultaneously. 18. A method of mining using a remote mining head assembly, said remote mining head assembly having an elongate body that has a forward face, and said elongate body having a circular cross section, and a plurality of electrodes that are located on the forward face, and a screen that is located in the central region of the forward face, and wherein the size and number of apertures in said screen are selected to match the size, shape and type of material being mined, and an inflow water conduit that is capable of flooding the cavity substantially in front of the forward face, and the end of the hole, and barrier means, a slurry outflow conduit, and propulsion means that are capable of driving the remote mining head assembly in either a forward or backward direction, and an array of sensors on the forward face that feed there sensor signal data to a logic control means that performs command and control functionality for the remote mining head, said method including the steps of:

a. creating a hole in a suitable location, and with a suitable diameter, at ground level , in the vicinity of the ore body that is to be mined, and b. inserting a length of conduit into the hole, so as to act as a starter lining for the propulsion system to engage with, and

c . using the array of sensors to position the electrodes at the optimum distance from the end of the hole, and

d. flooding the cavity between the forward end of the remote mining head and the end of the hole via the inflow water conduit wherein the water is contained in the cavity via the barrier means, and

e. operating the remote mining head assembly so that it uses an array of electrodes located on the forward face of the assembly to pulse discharge electrical current with sufficient frequency, voltage, and current, to cause the material in its vicinity at the end of the hole to fragment, and to thereby form a slurry, and

f. withdrawing the slurry from the cavity through the screen via the slurry outflow conduit, and then carried away from the remote mining head assembly to a separate ore processing plant, and

g. the array of sensors is capable of analysing the chemical composition of the material in the vicinity of the forward face, and this information is then fed back to the logic control means and is used to steer the direction of the remote mining head so that it can track along a particular seam of ore.

The method of mining, as defined in claim 18 wherein the remote mining head assembly also includes lining and sealing means, and a lining and sealing means feed conduit, said method including the additional steps of:

20. The method of mining as defined in claim 19, including the further steps of: a. incorporating a quick setting cement, such as an epoxy resin, into the paste, so that when the generated smooth and resilient trailing sidewall solidifies quickly and controllably.

21. The method of mining as defined in claim 19, including the further steps of: a. incorporating means to at least partially melt the drawn solid material, and apply that molten material to the sidewall whereat it quickly solidifies under the influence of the comparatively cold mine shaft sidewall.