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The scarcity of truck tyres combined with decreases in the availability of labour, increases in fuel costs and a buoyant international economy driving project budget blowouts, have all combined to change the paradigm behind mining equipment selections. The escalation of commodity prices has occurred in parallel with an increasing maturity in continuous mining machinery, mobile in-pit crushing systems and very large-scale conveyor belt systems. This paper will consider the merits of operating continuous materials handling systems, mobile in-pit crushing systems, relocatable crushing systems, relocatable conveyor systems and automated waste handling systems in place of the more conventional approach of truck haulage.

Jan 1, 2007

By Phillips J. T, Hutton W. A

This paper discusses why Argyle Diamonds adopted thickened tailings disposal in 1985 and how the system was developed over the next seven years. A wide ranging review of the thickened tailings disposal system and the tailings deposit it was producing was carried out during 1992 and 1993. The results of that review led to the abandonment of thickened tailings disposal at Argyle because of serious concerns about the stability of the resultant tailings deposit. The exposure to the risk of liquefaction and an assessment of the consequences if this happened to the thickened tailings deposit are shown. The criteria for selecting the new tailings disposal strategy are then described. The final section of the paper discusses the management strategies that have been put in place. These are designed to: ò reduce the risk posed by the thickened tailings deposit to an acceptable level; ò safely store tailings to the end of mine life; ò produce a land form that can be decommissioned to the satisfaction of Government regulatory bodies.

Jan 1, 1996

By M Szwec, P Corbett, P Sheffield

Centennial Coal operates the Springvale and Angus Place longwall mining operations that extract coal beneath the Newnes Plateau in the Western Coalfields of New South Wales. Springvale and Angus Place mines have a history of difficult geotechnical conditions, where mining operations are conducted with a thick coal roof interbedded with numerous claystone units and relatively high levels of vertical and horizontal stress. The combination of a relatively high stress regime and weak laminated roof has led to numerous roof failures throughout the mine’s life.Following underground roadway development, the mine roadways can experience high levels of roof movement that can lead to roof falls. Two-point wire extensometers (known as ‘telltales’) are extensively used for roadway condition monitoring. Along with extensive other geological and geotechnical data, monitoring data is used to prepare geotechnical hazard plans that are then used in all areas of mine planning to allow for safe and efficient operation of the mine.This paper presents a case study of the use of a new software tool that allows time-scaled visualisation of monitoring data in the context of longwall and development face positions and installed strata support. It can be used in the identification of geotechnical risk factors and their interaction with the mining process to allow a more robust geotechnical hazard process. It interfaces directly with the widely used ExtoChart database software and can be presented with scale drawings of geological/geotechnical data to allow correlation of monitoring data with risk factors.CITATION:Corbett, P, Sheffield, P and Szwec, M, 2014. A new tool for extensometer data analysis and improved understanding of geotechnical risk factors, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 217–232 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By E Wargem

The optimum mining of an orebody in an underground mining operation is fundamental to the mine’s ability to operate both sustainably and efficiently. The effective mining of an open stope or a cave is largely reliant on the recovery of the initial void created by conventional drilling and blasting. These initial voids are known by various names such as a Longhole Rise, Slot or Winze and can be mined either as a downhole or as an uphole. Regardless of the underground mining method, the process of the design and implementation of this initial void is largely uniform across many operations with various patterns of slot or winze designs used across these different operations. Diligent design, implementation and review strategies in drilling and blasting of these will facilitate cost-effective mining with minimal disruption to mine schedules and production targets. When an operation struggles in opening the initial void in underground mine blasting, it has a negative impact on productivity, mineral recovery, and the overall economics of mining. Near field blast vibration monitoring is a vital tool to use in analysing slot blasts and will provide additional feedback into the reconciliation part of the drill and blast process. It is one that is often overlooked in the mining industry in many operations due to many factors such as lack of skilled personnel, or a lack of required resources. The data obtained from near field blast vibration monitoring can be used to provide additional feedback into blast reviews and help in any drill and blast optimisation projects. This paper highlights key aspects of underground drill and blast reviews and the use of near field blast vibration monitoring for post blast analysis and shares learnings from various projects that the authors have been involved in within Australia and abroad.

Mar 29, 2023

Mining epitomises the challenge of sustainable development, because few sectors have such a direct impact on the natural environment, yet few are more important to the economic and social health of almost every region in the globe. In a global industry, with increasing competition for exploration and mining investment dollars, sustainable development must also be resolved within an international competitiveness framework. In formulating a response to the challenge of sustainable development, the State and Federal Governments do not fully appreciate the extent to which technology drives the solution on a range of issues. In some cases` a dangerous fatalism about the state of science has led to an unhealthy æstop productionÆ attitude that puts our industry and economy at risk. As a technical institute representing the professionals in the minerals sector, The Australasian Institute of Mining and Metallurgy (The AusIMM) sees one of its roles as being to highlight the way in which industry innovation can facilitate solutions. The AusIMM is currently evolving a greenhouse gas emissions policy. As a case study it throws into sharp relief the way in which irresponsible ælimits to growthÆ policies could have a negative impact on the sustainability of the sector, as well as the importance of a technology- based solution. With 80 per cent of greenhouse gas emissions in the next twenty years projected to come from developing economies, such as India and China, major reductions will only be achieved if cost-effective, low emissions energy technologies are deployed in developing countries, and more energy efficient processes of producing key commodities for them are brought online. As a supplier of the key energy resources and materials that will be in high demand to feed developing economies, and with knowledge intensive industries with excellent R&D links across mining and manufacturing, Australia is well positioned to contribute to develop key low emissions technologies. However, we will only be able to take advantage of this position if the Federal Government commits to a holistic greenhouse emissions policy that does not penalise industry. We need effective æpushÆ polices aimed at leveraging investment in low emissions R&D that are closely linked in to æpullÆ policies aimed at stimulating technology uptake.

Jan 1, 2006

By Dickson B. L

Groundwater geochemistry is controlled by chemical interactions with aquifer rocks, and offers a powerful geochemical exploration technique for locating concealed mineral- isation. Techniques are applied for identifying constituents of aquifers using the compositions of their groundwaters, collected from the surface through drill holes, water bores or springs. Even slowly moving groundwaters have passed through large volumes of rocks which surround any sample site. Products from these rock-water contacts modify the groundwater. By relating water composition to the minerals from which the dissolved species may have been derived, geochemical exploration information is obtained for a significantly larger zone than is represented by drill hole rock samples. In this paper we describe some solution chemical tech- niques we are applying in mineral exploration, particularly in areas of Australia where ground- waters are highly saline and contain enhanced concentrations of trace metals. EQUILIBRIUM MODELS FOR SALINE GROUNDWATERS Central to our technique is the assumption that in low rainfall regions, aquifer rocks and contained groundwaters are in chemical equili- brium. Solubility calculations then allow us to predict upper limits to the soluble products of groundwater interaction with aquifer rocks and to identify minerals with which the groundwater is saturated. Whilst equilibrium calculations require input of concentrations of all dissolved species, they are actually based on "activity" of dissolved species rather than the analysed concentrations. Unless waters have very low ionic strengths (a measure of total dissolved solids), activity of a solute is not equal to its analytical concentration but equals concentration multiplied by an "activity coefficent". Several methods exist for calculating mineral solubilities. The ion-association model, commonly used in programs such as WATEQ (Truesdell and Jones, 1974) and later deriv- atives such as MINTEQ, assume the formation of complex ions such as MgSO4(0), CaCl+, which are described by formation constants. Activity coefficients are obtained by the extended Debye

Jan 1, 1988

By T Dawson, B Haskins

Fatigue is it the newest buzz word or is fatigue a real phenomenon that is creating safety and organisational risk for you? There is no debate that fatigue is natural, and it affects us all, just like gravity; however, there has been much debate on the severity of its impact in the workplace. For many years the impact was not measurable, hidden out of sight and, quite frankly, written off as the infamous ‘operator error’. Over the last several years, advancements in technology have provided safety and health professionals, sleep scientists, fatigue experts and organisations with the ability to monitor and detect fatigue events in real time, as well as predict and monitor increased risk for fatigue events. Caterpillar Safety Services has assembled an extensive and exceptional set of technologies that will provide the best methods and data to measure the impact of fatigue. This paper will discuss fatigue in the workplace and review the technologies and data sets available, which will allow the reader to determine whether this risk is real or rubbish.CITATION:Haskins, B and Dawson, T, 2017. Fatigue risk in your operations – real or rubbish? It actually depends , in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 137–142 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By O Handayani, R Barr, E Isaaks

The mining industry has focused a great deal of attention recently on the impact of blast movement on grade control. Although the problem of blast movement and its contribution to dilution and ore loss is well known, solutions to the problem are less than satisfactory. Perhaps the most recent innovation is the application of blast movement monitoring (BMM) devices to quantify blast movement. These devices emit an electronic signal and are planted at surveyed locations within the preblast material. Following the blast, their new locations are found using an electronic scanner. The magnitude and direction of the blast movement is given by the vectors between the pre- and post-blast BMM locations. However, it’s not clear how the BMM vector data can be best used to minimise dilution and ore loss. One common solution is to displace preblast dig line polygons by distances indicated by the BMM vectors. However, studies of BMM vectors show that blast movement not only displaces material laterally but also mixes material internally within the bench (Thornton, 2009a).This paper presents a method for modelling the post-blast muck pile that accounts for displacement and internal dilution using simulated annealing. The preblast ore control block model is re-blocked to 1?×?1?×?1?m sub-blocks. Each sub-block is displaced by simulated BMM vectors conditional to post-blast surface topography and blast initiation sequence data in addition to BMM vector data. The displaced sub-blocks are aggregated into new ore control model blocks whose grades are calculated from the contained sub-blocks. New dig lines are then designed on the post-blast muck pile model using the new ore control block model grades. A case study based on actual data is provided.CITATION:Isaaks, E, Barr, R and Handayani, O, 2014. Modelling blast movement for grade control, in Proceedings Ninth International Mining Geology Conference 2014 , pp 433–440 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By P G. Bourke, A Yáñez, G J. Jameson, N M. L Kupka

The kinetics of fine and ultrafine particles in conventional mechanical flotation cells are limited (Feng and Aldrich, 1999; Trahar, 1981; Wang et al, 2016). Accordingly, even limited recoveries with such machines require long residence times. Theoretical investigations into the rate of capture of fine particles by flotation, have indicated that a key parameter is the rate of shear in the fluid surrounding the bubbles and the particles. Achieving fast flotation rates of ultrafines requires a new method of bringing the particles and bubbles into contact, utilising the beneficial properties of highly dissipative flows to break through the water boundary layer. In 2010, a new type of flotation cell known as the Concorde Cell was described, in which bubbles and particles are brought together in a sonic shock wave (Jameson, 2010). Earlier research had shown that when a dispersion of fine bubbles in liquid passed through a converging nozzle at the local speed of sound, the resulting shock wave downstream generates a mass of even finer bubbles in the flow as it passes through the shock wave. The fluid within the shock wave is highly turbulent, and an environment is created that is very favourable to particle-bubble collision and capture. In this paper, we briefly describe the Concorde Flotation Cell and give examples of its use.

Aug 24, 2022

An Integrated Geology-Mine-Plant and Eco-Efficiency Simulator for Anglo Platinum's Evaluation and Operational Improvement Initiatives

Sep 13, 2010

By Brown AP

Comparison of legal permits required for mining (as opposed to prospecting or exploration) in New Zealand, under the Mining Act 1971 and the Resource Management Act/Crown Minerals Act 1991. Mining generally receives the same treatment as any other industrial or commercial activity.

Jan 1, 1995

Gwalia Consolidated Ltd has been in the mining industry for about 15 years, yet its key wholly owned Greenbushes Mine has a history dating back to the last century. Similarly Gwalia Consolidated's associate, Sons of Gwalia Ltd owns the historic Sons of Gwalia and Marvel Loch Mines with Sons of Gwalia celebrating its centenary this year. This durability is a testament to the quality of the orebodies concerned and the massive technological achievements over this time which have enabled each of these mines to maintain their competitiveness. While Sons of Gwalia and Marvel Loch were and continue to be gold mines, the wholly owned Greenbushes Mine has survived and in fact prospered through the development of alternative products from its rich and unique pegmatite. Similarly, for Gwalia Consolidated to grow and prosper it will be necessary to expand the current portfolio of products and operations. The Greenbushes Mine has already given Gwalia world `No 1' status in both the supply of primary tantalite concentrates and lithium minerals (spodumene). The asset base contributed by Gwalia's gold investments assisted in the recapitalisation of the Greenbushes assets to fully develop their potential. Industrial minerals and strategic metals were of interest to Gwalia as these markets are relatively small and it is possible to develop an influential if not dominant position in the market with a quality asset. Capital expenditure to develop such projects are also usually in the order of $10 m to $20 m, a manageable range relative to Gwalia's size.

Jan 1, 1996

By Stevenson I, Dickinson W, Taylor R. N

Despite flash smelting's widespread use little is known about the actual processes taking place in flash furnace shafts and comparatively few reports of sampling campaigns have appeared in the published literature. his paper reviews the previous reports of the use of horizontal trough samplers and analyses their expected collection efficiency. In the light of the deficiencies revealed by this analysis an isokinetic sampler was produced and a vertical sampling technique was also developed to obtain samples from directly below the burners in the shaft of the flash furnace at the Kalgoorlie nickel smelter. Comparison of the sizing of the samples obtained with the horizontal trough and isokinetic samplers confirmed the theoretical analyses and showed that the trough samplers were not collecting the fine particles. Besides providing data to validate mathematical models of the burners and shaft, chemical analyses of the shaft samples showed that the coal in the charge was reacting preferentially and that the plume of at least one of the burners was being deflected from its axial position. In the region directly below the burner there was evidence that the disperser on the burner was imparting more momentum to the coarser particles and that these were concentrating in the outer regions of the particle plumes issuing from the burners.

Jan 1, 1992

By A Hilli, K Kosmara, J Steyn

PT Nusa Halmahera Minerals (PT NHM) is an Indonesian joint venture company owned by Newcrest Mining Limited (75 per cent) and PT Aneka Tambang (Persero) (25 per cent). PT NHM operates two underground gold mines, Kencana and Toguraci at the Gosowong mine site in North Halmahera District, North Maluku Province, Indonesia.On 8 February 2016, a major ground movement occurred in the K-Link orebody of the Kencana underground mine, effectively blocking the only two access ways to the stoping area. Following mine clearance, it was found that a Solo production drill rig operator, who had been drilling in the Level 10 Extraction Drive was still underground, cut off from the rest of the mine by the ground movement.Communication, nutritional and logistic supply to the trapped operator was established with the breakthrough of two diamond drill holes. A range of technical expertise and opinions from both on and off-site were sought and two options were chosen for implementation of the rescue operation. The rescue was completed successfully on 16 February 2016 with the operator being rescued in good physical and mental health.CITATION:Kosmara, K, Hilli, A and Steyn, J, 2017. Eight days entrapped – PT Nusa Halmahera Mineral’s rescue of a trapped miner, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 155–160 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

Most Geologists have a well rounded knowledge of the exploration phase and those who have worked as mine geologists have an understanding of the production phase. Few have had exposure to the development and the construction phases. Even fewer have had the experience of closing a mine, disposing of the plant and equipment, carrying out the final cleanup and making the area safe and environmentally acceptable.During the various phases of exploration, the geoscientist gains a wealth of non-geological information which can be of considerable value to engineers and technicians in the feasibili-ty, development, operation phases and finally the closure of a project. Such basic controls as surveys, adopted assay sample lengths and the location of items of infrastructure during exploration, may continue to affect the project through its entire life. Thus the geologist's responsibilities extend well beyond the explo-ration phase of a project.

Jan 1, 1990

Variety among deserts is nearly as great as among other climatic environments. Common to most deserts, and to areas downwind from them, is the dominance of aeolian transport of surface material, at least during some seasons of the year. The result is dilution of local surface materials with varying proportions of chemically uniform fine sand and silt, often imported by the wind from remote areas. Fortunately, desert pavement,.even though separated from bedrock by a meter or more of nearly pure loess, is simply a diluted reflection of nearby bedrock. Infiltration of loess through the surface debris and the rudimentary soil-forming processes in the desert usually preserve the integrity of the pavement. This pavement, or its "downstream" derivatives, provides a suitable sample for exploration geochemistry if proper care is taken to circumvent the aeolian dilution. The simplest and most commonly used method of circumventing the dilution is to use a coarse fraction of soils or stream sediments, discarding or retaining the finer fraction depending upon the magnitude of the dilution. Where the coarse surface debris is composed of rock chips representative of the bedrock sources, the method is successful. Under most circumstances the coarse fraction of the surface material will give a fair representation of gross lithology and will occasionally give an indication of mineral- ization. The major drawback to this approach is that selective weathering and erosion in the vicinity of mineral deposits often lead to the loss of ore minerals into the finer fraction, leaving a coarse residue enriched in feldspar and particularly in quartz; thus, the geochemical signature from a mineral deposit is effectively reduced or completely masked. The second most commonly used method to overcome aeolian dilution, and probably the most effective at present, is to use a heavy- mineral concentrate. This approach presupposes that the chemical signature sought resides in a heavy mineral. Fortunately, the arid weathering cycle is conducive to the formation of a wide variety of secondary ore

Jan 1, 1988

By P Velletri, N Gaylard

The management of wear surfaces in mining operations has remained largely unchanged since the inception of mining. Sacrificial wear liners are installed on the inside of chutes, hoppers and other equipment used to transfer bulk ore to protect the asset from abrasive wear caused by the flow of material. These liners are generally replaced at fixed intervals which may be determined based on historical wear rates or may be driven by other maintenance requirements for that asset. This approach does not always yield satisfactory results, especially for critical assets where the impact of downtime on production can be substantial. For such assets, a condition-based maintenance strategy has the potential to significantly increase productivity and reduce the total cost of ownership associated with the asset. However, for such a strategy to be successful, timely information on the actual condition (remaining thickness) of the wear liners is essential. This paper describes the development and implementation of a wear monitoring system that can be used to remotely and continuously report on remaining liner material thickness in real time. It details some of the challenges that were overcome when developing the system, including the design of a patented thickness measuring system that can be used in a variety of liner materials and is tolerant to the presence of ore on the wear surface. The paper also explains how a cloud-based approach enables data from the wear sensors to be integrated into external systems such as a data historian, which has been demonstrated through a collaborative project with one of the largest iron ore producers in the Pilbara. This ability to combine real time liner thickness information with other data sources, such as throughput, provides the foundation for the transition to a condition-based maintenance strategy.

Nov 8, 2021

By Oda Y, Hashiuchi M

In the smelting section, flexible fuels such as coal or coke are used in place of heavy fuel oil in order to utilize energy sources more efficiently. Heat recovered from the off gas of the furnace has been converted by the waste heat boiler into steam, which is used for self power generation and for heating or maintaining various temperatures. The amount of the recovered steam in the smelter is currently increasing due to maximum utilization of powdered cokes. The heat source required to maintain the temperature of the electrolyte in the tank house is electric power and steam. However until recent year this steam was provided by its own heavy oil combustion type boiler in the tank house since the amount of steam consumed in heating the electrolyte is large. Though experimental work over the last few years has shown the advantages of reducing steam in the tank house by fully covering the cell, the implementation of the full cover can lead to other operating problems. However various improvements, mainly the covering of the cell with a simple device, have led to greatly reduced steam consumption. As a result, steam for the tank house is now provided by the waste heat boiler only bringing more efficient energy usage.

Jan 1, 1987

By J J. Van Wijk, A R. Penney

Successful management of geotechnical risk at a mining operation is more than just having a good ground control management plan or using advanced numerical modelling and the latest monitoring technologies. The fundamental requirements for effective geotechnical risk management include identification of potential failure modes, identifying and implementing appropriate controls, and demonstrating the effectiveness of those controls. Effective geotechnical risk management requires an integrated approach by confirming that appropriate risk management systems have been identified and implemented (management plans, procedures etc), and that these systems are executed consistently in the field across all working areas. Development of a thorough integrated auditing process executed by an experienced team of technical subject matter experts with substantial operational knowledge, provides a more complete picture of catastrophic hazard management. Following consistent evaluation criteria allows benchmarking of systems and implementation compliance between the sites being audited, and the results can then be ranked against other operations in an industry database.

Nov 29, 2022

By Morley I. W

In the year 1926, Edie Creek, in the Morobe District of the Mandated Territory of New Guinea, saw the greatest gold rush of recent years. Situated 35 miles inland from the coast, and at an altitude of over 6000 feet, Edie Creek presented to the original prospectors a wet, jungle-clad uninhabited, and inhospitable region. There were no roads; and the only means of approach from the equally inhospitable coast was by an eight to ten days' tramp through coastal swamps and gorge-scarred mountains. All food supplies and equipment had to be carried on the backs of "kanakas," and in many cases through country occupied by hostile natives.Since the first discovery of payable gold at Edie Creek, mining on the Morobe Goldfield has shown remarkable progress, and in spite of the tremendous natural difficulties, the field today ranks as one of the most important in Australasia.Aeroplanes, more than any other factor, have been responsible for this rapid development. They provide the only means of transport from the coast, and at present serve the needs of over 600 Europeans and 3000 indentured native labourers engaged in the industry.

Jan 1, 1933