SME Annual Meeting Feb. 28-Mar. 03, 2010, Phoenix, AZ

1 Copyright 2010 by SME

Preprint 10-116

MINE PRODUCTIVITY AND TECHNOLOGY RESEARCH IN AUSTRALIA

M. Hood, CRCMining, Brisbane, QLD, Australia

ABSTRACT

Australia is a hub for mining technology development. The paper describes many of the key players involved in mining research in this country along with some of the interesting research outputs to emerge over the past decade.

INTRODUCTION

Australia is one of the few developed countries where mining is a significant industry. In 2006 mining generated 8% of this nations GDP and 49% of its total goods and services exports. Despite this, the general public would be surprised to learn that mining, widely considered to be a low-tech, dig-it-and-ship-it business, is, in reality, an extremely productive, high-technology industry. The public might be even more surprised to learn that Australia is the global hub for mining technology. Indeed, mining technology in Australia is a very important industry in its own right with annual export value of mining technology products and services is roughly the same (at $2.5 billion) as the much-vaunted wine industry. This paper focuses on mining R&D, as opposed to exploration R&D or minerals processing R&D, and describes the countrys research infrastructure and some of the major technologies that have been developed in recent years.

THE PLAYERS

Follow the money is generally good advice and so, in trying to analyse who does what research and to what purpose, we start by asking who funds mining research in Australia. The answer is a combination of the mining industry, equipment suppliers and the Australian Government. The mining industry funds R&D in a number of ways. One is comprehensive, stand-alone funding to support major strategic projects with the idea of owning or controlling the technology that is developed. Sometimes, but increasingly rarely, this work is conducted by in-house teams; the fashion for mining companies to maintain significant in-house mining research capability has largely gone. More commonly a mining company works with a strategic partner to develop a technology. A current example is Rio Tintos support of the Australian Field Robotics team (ACFR) at Sydney University to develop automation technologies for mobile equipment in open pit mines (more on this below).

Another example of the way that mining companies fund R&D is provided by the black coal industry. Every tonne of black coal produced in Australia carries a levy of AUD$0.05. This money, about $15 million a year, is collected by the Australian Coal Association (ACA) and used to fund research through the ACA research program, known as ACARP. Each year the coal mining companies work together to define the research priorities for the coal industry. They publish these priorities and research providers -- universities, government laboratories, consultants and others -- submit research proposals in response to these priorities. ACARP teams evaluate these proposals and fund those that they rank highly. The unique feature of this process is that a large number of people from the mining companies -- mine site staff as well as head office staff -- are engaged is priority setting, proposal evaluation, and project monitoring. This high level of industry engagement means that the technologies, when they emerge from the hallowed halls of academe, have on-site champions waiting and eager to deploy and utilise them. As important, it also means that technologies that fail to make progress are culled. Anyone who has been involved in developing and commercialising

technologies in any field will recognise these as the two essential features for managing these processes successfully: (i) having a receptive market (technology-pull rather than technology-push) and (ii) having the discipline to kill off projects that do not meet milestones.

A third way that companies come together to support mining R&D is through the Australian Minerals Industries Research Association (AMIRA-International -- formerly AMIRA). This highly-respected organisation provides a research-brokerage service to the industry. It employs a number of Research Coordinators; their role is to maintain a close familiarity with the technology problems facing the minerals industry and to maintain an awareness of the research capabilities within universities and other research providers. These Coordinators work with their member companies and the appropriate research providers to develop and fund projects that address or solve the identified technology problems. AMIRA-International works mainly in the fields of exploration, minerals processing and extractive metallurgy but does manage some projects in mining. Although its roots are in Australia, as its name suggests it now operates in many countries around the globe.

The Australian Government supports mining research through two principal mechanisms, the national research organisation CSIRO and the Cooperative Research Centres (CRC) Program. CSIROs mining research is conducted mainly through its Division of Exploration and Mining and its relatively new Minerals Down Under Flagship.

Cooperative Research Centres (CRCs) are competitively funded entities which are structured such that the end-users of the research are put in charge of the research program. They seek to bring together a critical mass of researchers, generally from several institutions, to solve specific end-user problems in a defined period of time. There are more than 50 of these Centres operating throughout Australia in a wide range of fields from medicine to manufacturing to mining. With a single exception, those CRCs in the Mining and Energy Sector all operate in either exploration or extractive metallurgy. That exception is CRCMining which develops new technologies for mining. It is a joint venture between many of the worlds major mining companies1, some large mining equipment manufacturers2, a large information technology company3, a number of small-to-medium sized enterprises (SMEs), and five leading Australian universities4. CRCMining has been operating continuously since 1991 (originally under the name CMTE) and has developed and has commercialised, or is commercialising, a number of step-change technologies; some of these are described below.

In addition to CSIRO and CRCMining the universities also conduct research and develop technologies for mining. Obviously mining is a very large industry with a broad spectrum of technology needs and universities throughout Australia have a very wide range of research interests, some of which are developed for, or employed by, the mining industry. It would be impossible to cover this field in this short paper. The main universities involved in mining (narrowly

1 Anglo Ashanti Gold, Anglo Coal, BHP Billiton, Rio Tinto Technology

and Innovation, Rio Tinto Iron Ore, Freeport McMoRan, Newcrest, Peabody Energy, and Xstrata Coal

2 P&H MinePro, Caterpillar, Herrenknecht 3 Computer Sciences Corporation

4 The universities of: Queensland, Western Australia, Sydney,

Curtin, and Newcastle

defined) research are the universities with undergraduate Bachelors programs in mining engineering: New South Wales (UNSW), Queensland (UQ), Curtin, Wollongong, and (recently) Adelaide. Professor Bruce Hebblewhite, who runs the mining program at UNSW, is speaking at this meeting so I wont try to steal his thunder by describing mining research at that institution. Bruces paper describes Australian coal-related research and he gives details about activities not just at UNSW but also at Wollongong. A broad range of mining-related research is carried out at UQ (separate to the research work conducted by CRCMining, which is headquartered at UQ) under the umbrella of the Sustainable Minerals Institute. This organisation comprises six research centres: the Julius Kruttschnitt Mineral Research Centre (minerals processing research), the WH Bryan Mining and Geology Research Centre (mine planning, mass mining, geometallurgy, and geology), the Centre for Mined Land Rehabilitation, the Minerals Industry Safety and Health Centre, the Centre for Social Responsibility in Mining, and the Centre for Water in the Minerals Industry. Curtin Universitys mining-specific research is mainly in the field of rock mechanics, particularly ground support for hard rock mines and understanding rock mass conditions in large, deep underground mines. This rock mechanics work is carried out through CRCMining. Mining research at Adelaide University is concentrated in geostatistics.

EXAMPLES OF RESEARCH OUTPUTS

Rio Tintos Surface Mine Automation Program Rio Tintos Surface Mine Automation Program is one of the

largest non-military automation programs being undertaken in the world today. The aim is to progressively automate equipment and the processes commonly used in surface mining. This will lead to the integration of the systems and equipment used in the mining process to better use the data and information collected and bring the sometimes chaotic process of mining into better control.

The program is composed of many parts, ranging from the testing and assessing automated systems being produced by original equipment manufacturers (OEMs) -- e.g. Komatsus autonomous haulage system -- through to the development of bespoke systems tailored to Rio Tintos specific needs -- e.g. the modification of OEM blast hole drills for autonomous operation).

The program is now in its third year and at its heart is the Rio Tinto Centre for Mine Automation (RTCMA) which has been created by the Australian Centre for Field Robotics (ACFR) at the University of Sydney. This is a group of over 40 researchers and technicians who are building the overall architecture for the autonomous surface mine and assisting with the creation and modification of the sub-systems to make it a reality.

To this point the program has been very successful. The basic architecture of the automated mine is now virtually complete and work is progressing on fielding the first sub components. Rio Tintos automated blast hole drill rig is perhaps the most advanced early deployment of an internal system and the prototype rig has been operational with varying levels of autonomy for 18 months now (Figure 1). The rig is used routinely in autonomous mode with supervision from an operator monitoring performance back at the mine office. The second and third automated drills are currently undergoing commissioning and a single operator will be controlling multiple drills before the end of 2009.

Rio Tinto is working with several OEMs to improve their own automated products and allow their seamless integration into the so-called Mine of the Future. Many of these initiatives are being demonstrated at the West Angeles Iron Ore mine in the Pilbara region of Western Australia. This provides a good focal point for the program and allows early experiences and challenges of operating and combining independent systems to be gained.

CSIROs development of Autonomous Load-Haul Dump machines (LHDs)

Automating mining equipment and, ultimately, mining systems is a major trend in the industry. One of the first pieces of equipment to be automated was the LHD. CRCMining (when it was known as CMTE) with two of its research partners at the time, CSIRO and the Australian Centre for Field Robotics at the University of Sydney, and in partnership with Mt Isa Mines and Caterpillar, helped to pioneer this development. CSIROs researchers took the lead role in this R&D and the technology ultimately was commercialised by them under a licence

agreement with Caterpillar. The project was funded by a number of industry sponsors through AMIRA.

Figure 1. Operator cab of autonomous drill at Rio Tintos West Angeles mine.

The innovation from the CSIRO team was the development of an algorithm that could use the output from a 2D laser scanner to both steer the LHD and locate it within the system of mine tunnels. A technique based on constrained active contours (snakes) was developed (and patented) that could determine the correct steering angle for the LHD based on the free space in front of the vehicle (Figure 2). Precise localisation was not required and so the system is considered a relative navigation system. Only a rough location along a particular tunnel is required to upload the driving hints and this rough position estimation is achieved using so-called opportunistic localisation where the system recognises features in the 2D laser scans at tunnel intersections. The combination of a relative navigation and steering system with the opportunistic localisation results in an infrastructure free navigation solution. The only infrastructure required is a radio communications system.

Figure 2. Constrained active contours used to determine steering command, skeletonization to localization.

In parallel, Western Mining Corporation (now part of BHP Billiton) supported a separate LHD automation project through an Australian start-up called Lateral Dynamics. Ultimately, the two projects were amalgamated and the CSIRO worked with Caterpillar and its newly formed company, DAS (joint venture with Lateral Dynamics), to commercialise the technology. The resulting product called Minegem was launched in 2004 and is operational throughout the world using CSIROs relative navigation solution.

Sustainable Minerals Institute development of blasting software One of the major research centres of the Sustainable Minerals

Institute (SMI) at the University of Queensland is the Julius Kruttschnitt Mineral Research Centre (JKMRC). This Centre has been involved in applied blasting research globally for more that 20 years and has acquired the reputation as one of the leading applied research blasting groups worldwide.

The Centre developed monitoring systems for blast vibrations and explosives performance; these were commercialised through private companies. The research focus then shifted to blast modelling which led to the development of commercial blast design (layout) and analysis software, JKSimBlast. This software is used for numerous blasting applications including: bench, ring and tunnel development. More recently this blasting research has been focused on development of numerical models to predict blast fragmentation, blast damage and

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blast movement. Digital image analysis has been used to measure fragmentation size distributions and a novel technology has been developed for the direct measurement of muckpile movement during blasting for subsequent grade control. The former methodology which was developed in conjunction with the University of Arizona led to the development of Split imaging system. Split is now a practical commercial tool for which providing accurate 3-dimensional blast movement data.

In making these developments the JKMRC team benefited significantly from the prior work conducted by the USBM; in particular from the controlled and well-instrumented experiments that the Bureau conducted during the 50s and 60s. This work provided the data sets that the JKMRC used to develop blasting models and technologies described above. More than 20 students gained their doctorates working on blasting-related topics at the JKMRC and the seminal work by the USBM has been cited in most of these Ph.D. theses. An example of the work and papers listed are included in the bibliography with this paper. The emphasis of the current blasting research now being carried out at the SMI is on improved understanding of how explosives detonation affects rock breakage. The work by the USBM, now NIOSH, continues to be applicable.

CRCMinings vehicular collision avoidance technology Hundreds of accidents involving vehicles occur on mine sites

each year. Many are caused by operator fatigue or operator error. Many, too, are caused by poor environmental conditions such as fog, dust, or snow. These often compound the inherent problem of extremely poor visibility from the cabs of mine haul trucks and other mine vehicles (Figure 3).

Figure 3. Typical blind-spot regions for drivers in haul trucks.

CRCMining, through its University of Sydney partnership at the ACFR, has developed a technology that provides vehicle operators with improved situational awareness using a range of sensors and smart software to monitor nearby threats. This technology provides a comprehensive approach to vehicle safety using a high-integrity proximity system. Information about the vehicle situation and nearby threats is communicated between vehicles using a robust multi-radio system. The interface with the operator is designed to reduce false alarms and only interact with the operator when there is relevant and useful information. Post processing of this data reveals statistics about the safety performance of each operator. These statistics are then available for the mine management to provide incentives, rewards and enforcement aimed at improving the safety culture of the operators. Furthermore the application of this technology is also presented as an essential component to address interaction in a mine that mixes autonomous and manned resources.

There are two types of proximity systems; active systems where specially fitted vehicles communicate through some kind of network, and passive detection systems where each vehicle must use sensors such as radars, lasers, etc. to try and detect other vehicles. For use in a mine, passive systems do not provide enough information for a

comprehensive proximity system, and also suffer from unavoidable false alarms. For an active detection system, it is important that there is redundancy in the system. This is in case there is a failure in one of the active systems, there will be a backup to detect nearby vehicles. Two active detection systems are used in this system. The first is a high bandwidth, long range system using 2.4 GHz wireless networking to allow the transfer of data. The second is a close range system built for robustness of detection and reliability.

For the long range proximity system to work, it is important that a reliable communication network is established. To achieve this, a self healing and robust wireless mesh network has been implemented. Figure 4 shows how the multi-hop capabilities of this network are implemented using each vehicle as a node on the network. The vehicles then form a mesh structure allowing data to be transferred between network agents that are not in direct range. One of the main advantages of this type of network it that it does not require any sort of infrastructure.

Figure 4. Mesh Network between the base station, haul truck and light vehicles. Arrows indicate a network connection between network agents.

A close proximity system has been designed as another mechanism to detect nearby vehicles and personnel, supplementing the long range proximity to increase the availability and reliability of the overall system. This system uses a radio frequency (433 MHz) which is different to the long proximity, reducing the chance that any interference would affect both systems simultaneously. In addition, the close proximity does not rely on GPS, meaning that if there are insufficient satellites for GPS coverage, an estimate of location can still be used to warn operators of impending problems.

This technology was successfully trialled at Freeports Grasberg mine, Rio Tintos Brockman mine and at Codelcos Andina mine. It has since been developed into a commercial product through a spin-off company AcuMine.

CRCMinings SmartCap Operator fatigue is responsible for numerous injuries, many fatal,

in the mining industry. Over the past decade a number of commercial products have been developed to monitor operator fatigue. At present these all use indirect measures, such as eye/head behaviour or operator response time, to determine fatigue levels. These indirect measures are unable to cope with driver-to-driver variations.

The technology known as Smartcap, developed by CRCMining, overcomes this serious limitation by using a non-intrusive technique to measure the operators brain wave (EEG) information, thereby giving a direct, physiological measurement of fatigue. This brain wave information is monitored using sophisticated sensors concealed in the lining of a conventional baseball cap (Figure 5). The innovation was achieved using small sensors and clever software capable of reading and interpreting EEG through hair, without the need for any scalp preparation. This EEG data is processed by a computer, that is fitted into the cap brim, to calculate a measure of drowsiness. This information is communicated wirelessly to an in-cab display and to the mine office.

Figure 5. Haul truck driver wearing the SmartCap.

The technology was proven in two successful field trials in Anglo Coals surface coal mines in central Queensland, Australia in 2008. In total, 53 operators were involved in these trials for one or more shifts. The trials were conducted on both day and night shifts and involved operators of haul trucks, excavators, water trucks, dozers and graders. Infrared video footage of some operators was captured for comparison with the EEG measurements. In particular, this video footage allowed the calculation of the percentage of eye closure (PERCLOS) of eleven operators. Comparison of the PERCLOS measurements with operator fatigue levels shows good correlation in line with similar published research. The robustness of the electronics in terms of noise rejection and connectivity were also tested, and in all aspects, the Smart Cap system performed according to its design parameters. Most importantly, operator acceptance of the technology was beyond expectation, with 51 of the 53 operators indicating support for the introduction of the tool as a compulsory safety initiative.

Anglo Coal is working with CRCMining to ruggedise the product. This process will be completed by the end of 2009 and Anglo Coal expects to install this technology across all of its open cut mines in Australia during 2010. It is available commercially through a spin-off company, EdanSafe.

CRCMinings Tight-Radius Drilling Technology Gases adsorbed in coal are released when seams are mined. In

underground mines the release of these gases (principally methane and carbon dioxide) pose a significant hazard to the safety of miners; to mitigate this hazard these gases must often be drained prior to mining. The principal method used for draining these gases is drilling in-seam from the underground workings. However, increasingly today this drainage is being accomplished by inclined holes drilled from surface and deviated to the seam horizon; so-called medium-radius drilling, MRD . This inclined hole is steered to intercept a vertical dewatering well (Figure 6).

Figure 6. Medium-radius drilling.

Methane, of course, is a valuable and (relatively) greenhouse-gas friendly fuel in its own right. Consequently a new industry (the coalbed

methane, CBM, industry) has developed to extract and utilise methane regardless of whether the seams that contain this gas are to be mined. The CBM industry is large and is growing rapidly worldwide. The principal impediment to even more rapid take up of CBM is the high cost of drilling.

CRCMining has developed a surface to in-seam drilling technology, tight-radius drilling, TRD, that complements and, in some cases, surpasses MRD in terms of both cost (lower) and the effectiveness of gas drainage (higher). TRD is essentially a well stimulation technique. It allows any number of holes to be drilled radially in each of multiple coal seams from an existing vertical well that intersects these seams. These radial holes are excavated using a drill powered only by high pressure water jets. The cutting jets on the front of the drill excavate the coal as they rotate. The drill is pushed forward by a number of stationary (non-rotating) jets that emerge from nozzles at the back of the drill.

Because the drill requires no mechanical force it is connected to the surface by a flexible high pressure hose. The drilling proceeds by initially drilling and casing a vertical well using standard procedures. A cavity, about 1.3m in diameter, is then reamed at each coal seam horizon where TRD radial holes are to be drilled. A dual-wall drill pipe is lowered down the hole with an erectable arm (whipstock) on the end. The whipstock, with the arm in a vertical position, is located at the horizon of the first seam that is to be drilled. The hose is lowered into the well until the drill drops into the arm. The arm is then raised, the water pressure applied and the drill launches itself from the whipstock and drills a hole roughly 200m in length into the seam (Figure 7).

The drill is equipped with a standard inertial navigation sensor package and a through-the-ground communications system, hence the drill manager knows the drill location during the drilling process. Moreover, the drill has a steering bias and the drill manager can accurately rotate the drill thereby controlling the drilling direction at all times.

This technology has been developed jointly by CRCMining and BHP Mitsui Coal over the past decade. Successful field demonstrations of the technology have been made at BHPs Moura mine (now Anglo Coals Dawson mine), Anglo Coals Grasstree mine, BHP Illawarras Dendrobium and Appin mines and, more recently at Rio Tintos Mt Thorley mine. The intellectual property is held by the spin-off company CBM Innovations and this company is currently seeking a partner to deliver this technology as a commercial service.

Figure 7. Schematic of tight-radius drilling (TRD) operations. CRCMinings Universal Dig-and-Dump Dragline (UDD) Technology

Draglines are the workhorse machines of the open cut coal mining industry, responsible, in many mines, for removing the overburden to uncover the coal seams. The traditional dragline rigging, which has not changed for many decades, involves a complex arrangement of chains and ropes (Figure 8a). The carrying capacity of a medium-sized dragline is of the order of 100 tonnes but the rigging alone accounts for about 15 tonnes, or 15% of the payload. A considerable incentive exists, therefore, to simplify the rigging and

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CONCLUSIONS thereby increase the payload and productivity of the machine. CRCMinings innovative UDD system eliminates the miracle hitch and most of the other associated rigging and manipulates the bucket by attaching a rope to the back and another to the front and then operating these ropes independently (Figure 8b).

The U.S. Bureau of Mines was a world-leader in many fields of mining research notably rock mechanics, including rock fragmentation. Much of their work has been continued by others, including, as noted in this paper, their pioneering work in blasting. The world remains grateful to this illustrious organisation for its contributions. Although minerals and fuels are the building blocks on which our civilisation depends, there are only a few countries which have both the motivation -- because the extraction of these minerals and fuels is a major part of their national economies -- and the capability to develop new technologies that will significantly improve mining safety and mining productivity. Australia is one of those countries. This paper sought to highlight some of the Australian research activities that have led to outputs that are now being utilised by industry.

Figure 8. (a) Conventional dragline rigging, (b) Universal dig-and-dump (UDD) rigging.

This description makes the technology sound easy, if not obvious, but there are complications. The principal difficulty is that an operator cannot manoeuvre a 100 t mass at the end of a 100 m boom with two independently-controlled hoist ropes and the associated drag ropes with only one master switch. This difficulty is overcome by a computer control system. Another difficulty is that because the hoist ropes are driven independently the hoist drum must be split; often this requires additional motors and a new gearbox and the sheaves at the boom tip must be moved from a side-to-side position to an in-line position. In other words, this technology involves a major engineering retrofit.

The benefits, however, are considerable. First, the UDD dragline can either deliver a 15% payload increase or the equivalent increase in hoist speed. Second, and perhaps just as important, is the ability of the modified UDD machine to pick the bucket up and to dump in any position. Conventional rigging constrains the bucket pick up location to near the tub. If the operator tries to pick the bucket up before it is close the the machine house the rigging causes much of the dirt to spill onto the ground; this increases cycle time. Also, with conventional rigging the bucket can be tipped vertical, and therefore dumped completely, only underneath the boom point; this, obviously, limits where dirt can be dumped. These two factors which greatly constrain the mine layout are overcome by employing the UDD system.

Six draglines in BHP Billitons Mitsubishi Alliances fleet have been retrofitted with the UDD technology to date. Although initial teething problems were encountered these have all now been overcome and all of these draglines are significantly outperforming all of the other (roughly 28) machines in the fleet. The technology has been commercialised through two intellectual property holding companies, UniDig and UniDig2, and licensed to P&H MinePro for some dragline models.

BIBLIOGRAPHY

Johnson, J B, 1962. Small scale blasting in mortar. USBM R.I. 6012.

Stagg, M S and Nutting, M J, 1987. Influence of blast delay time on rock fragmentation: One Tenth Scale Tests. Surface mine blasting proceedings: Bureau of Mines technology transfer seminar, US Bureau of Mines, April, 79-95.

Stagg, M S and Rholl, S A, 1987. Effects of accurate delays on fragmentation. Second International symposium on rock fragmentation by blasting, Colorado, USA, 210-223.

Stagg, M S, Rholl, S A and Otterness, R E, 1989. The effect of explosive type and delay between rows on fragmentation. Proceedings of the fifteenth conference on explosives and blasting technique, New Orleans, Louisiana, SEE, 353-366.

Stagg, M S, Rholl, S A, Otterness, R E and Smith, N S, 1990. Influence of shot design parameters on fragmentation. Proceedings of the third international symposium on rock fragmentation by blasting, The Australasian Institute of Mining and Metallurgy, Brisbane, Australia, 311-317.

Stagg, M S, Otterness, R E and Djahanguiri, F, 1994. Prediction of blast fragmentation of underground stopes for in situ leaching. Proceedings of the 10th annual symposium on explosives and blasting research, Austin, Texas USA, 197-208.

Blair, B.E., 1959. Use of high-speed camera in blasting studies. RI 5584, United States Bureau of Mines.

Rholl, S.A., 1987. Computer modelling of rock motion. IC9135i, US Bureau of Mines, Minneapolis, MN, USA.

ACKNOWLEDGEMENTS

This paper was written with significant contributions from Andy Stokes (Rio Tinto), Jock Cunningham (CSIRO), Gideon Chitombo (SMI), Daniel Bongers (CRCMining) and Eduardo Nebot (ACFR). Their contributions are gratefully acknowledged.

MINE PRODUCTIVITY AND TECHNOLOGY RESEARCH IN AUSTRALIA ABSTRACTINTRODUCTIONTHE PLAYERSEXAMPLES OF RESEARCH OUTPUTSRio Tintos Surface Mine Automation ProgramCSIROs development of Autonomous Load-Haul Dump machines (LHDs)Sustainable Minerals Institute development of blasting softwareCRCMinings vehicular collision avoidance technologyCRCMinings SmartCapCRCMinings Tight-Radius Drilling TechnologyCRCMinings Universal Dig-and-Dump Dragline (UDD) Technology

CONCLUSIONSBIBLIOGRAPHYACKNOWLEDGEMENTS