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The major technological advances of the last 30 years have profoundly reshaped mining practices. Machines keep getting bigger while productivity continues to increase and manning levels drop. These trends will continue and the introduction of breakthrough technologies will continue to accelerate, driven by a continued focus on lowering the cost of production, improving the productivity of workers and machines, and ensuring safer working environments. At the same time, global consolidation of mining companies has impacted on technology development in a range of ways. There are many potential technologies being proposed, some already operating in Australian mines. The automation of underground load-haul-dump (LHD) trucks for example, continues the process of removing workers from the most dangerous operating environments. Global positioning systems fitted to draglines, fibre optic communication channels, and 400 tonne trucks are only some examples of what lies ahead. However, where we need to return focus is to the technology of management û which is also one of the two key interrelated themes of this keynote address. Have we, as an industry, adequately been able to keep up with technological advances? Are our management systems as competent as the machinery we employ? The other key theme is the processes of globalisation and consolidation. What are the impacts on our industry? What are the implications of these processes, particularly for the ways in which we manage our people? My paper is divided into several components:some comments on the coal industry and the dramatic restructuring we have seen in recent years; in the context of this restructuring, an overview of my company and its evolution; my views on the role of contractors; some comments on the consolidation also occurring in the mining machinery and equipment, technology and services sectors; some observations on two major areas of technology û drill and blast; and trucks, shovels and excavators; the implications of consolidation and new technology for our employees and management; and finally some comments on research programs.

Jan 1, 2001

As part of its Concentrator operation Hamersley Iron Pty. Limited uses wet high intensity magnetic separation to upgrade shaley low grade ore in the minus 0.5mm size range. Materials handling problems, largely caused by fine ore types and design deficiencies, surfaced in the Fines Treatment Plant soon after Concentrator commissioning in 1979. Surging throughout the circuit impaired process efficiency and added to problems caused by capacity and process control limitations. In 1981 extensive modification works were initiated to supplement minor changes made to that date. The new circuit significantly increases capacity and provides greater process control.

Jan 1, 1978

By C Mpodozis

Central Andean (22¦S to 34¦S latitude) Miocene giant ore deposits share common features that reveal their origin. Tectonic and magmatic features include a relation to a shallow subduction zone, an association with the waning or initiation of a magmatic episode, emplacement at the time of uplift associated with crustal thickening and formation at times of major magmatic changes along the Andean margin. Rare Earth Element (REE) signatures in magmas erupted near the time of mineralisation indicate a progressive change from equilibration at depth with a hydrous, intermediate-pressure amphibole-bearing mineral residue to equilibration with an anhydrous high-pressure garnet-bearing assemblage. These features point to a common history. First, a relatively shallow subduction zone leads to hydration of a cool mantle wedge providing a source of fluids which builds up over at least several million years. Arc magmas formed at this time equilibrate with a hornblende-bearing residual mineralogy. Second, a compressive tectonic regime leads to crustal shortening and thickening that facilitates entrapment of arc magmas in the crust. Eventually, the magma-weakened crust yields to horizontal compression causing rapid crustal thickening. Fluids required for mineralisation are liberated as amphibole-bearing assemblages break down to garnet-bearing ones and over pressured fluids are released from plutons. Mineralisation subsequently ceases in the region unless continued dehydration of the slab and mechanical thinning of the continental lithosphere causes the previous conditions to repeat. The type of mineral deposit generated depends on the pre-existing continental lithosphere and the distance from the trench.

Jan 1, 1999

By D Duan

In this study, aimed at two kinds of ore (lump ore and iron ore fines) and four types of Australian iron ore resources (haematite iron ore, Mara Mamba iron ore, limonite iron ore, and mixed iron ore, such as Newman, MAC, Yandi and Pilbara iron ore), the physical and chemical properties and high-temperature properties were investigated in detail, to master their behaviour and effects in sintering, blast furnace, and non-blast furnace processes. Then, according to the individual properties of Australian iron ores, Chinese domestic iron ores and Brazilian iron ores, etc, the optimisation of ore-proportioning for sintering, blast furnace, and non-blast furnace processes was studied based on the interaction of the individual iron ores and their complementary properties, and the corresponding tests were carried out. The test work results indicated that this method not only improved the technical and economic indexes of sintering, blast furnace, and non-blast furnace processes, but also increased the addition of Australian iron ore. All of these provide the theoretical basis and technical support for highly effective use of Australian iron ore resources in iron and steel enterprises in China.

Jul 11, 2011

By A Cranley, A Giblett, S Thacker

The Newmont Tanami Operations are located in the Northern Territory, approximately 550 km north-west of Alice Springs. The Granites process plant commenced operations in 1986 as a 300?000 t/a ball mill / carbon-in-leach (CIL) plant and has undergone numerous expansions between that time and the current day, with project-to-date gold production exceeding 6.5 Moz. Annual plant throughput has exceeded 2.8 Mt/a while processing a blend of open pit material and ore from the Callie Deeps underground mine, with annual gold production exceeding 400 koz. In 2013 the operation processed 1.8 Mt of underground ore for the production of 323 koz of gold.This paper reviews the operation and expansion of The Granites process plant since the mid to late 1980s with particular focus on the gravity gold recovery circuit. The Tanami ores contain significant levels of free gold, and gravity recovery has long been an integral component of the metal recovery process at the Granites plant. The results of ten years of gravity circuit performance analysis and optimisation are presented.CITATION:Giblett, A, Cranley, A and Thacker, S, 2014. Three decades of gold production at the Newmont Tanami operations, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 209–216 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

Mr Chairperson, respected leaders of the mining industry, ladies and gentlemen;   Good morning, Kiora, Nihao.   I am very honoured to give a speech to the 2005 New Zealand minerals conference. I would like to take this opportunity to express my sincere thanks to the Ministry of Economic Development to invite me to be part of this important event.   Today, I am going to talk about two themes: a brief introduction of ChinaÆs economic development, including ChinaÆs energy strategy; the good bilateral relations between China and New Zealand, its potential for further development and its relevance to our cooperation in the field of minerals and energy.   It is a well-known story that over the past 27 years, great changes have taken place in China. In 1978 when ChinaÆs reform and opening up just started, its gdp was near to only 150 billion usd dollars. By the year of 2004 it reached to 1.6 trillion usd, an average of yearly growth rate 9.4 per cent.   ChinaÆs great achievements are widely appreciated both in China and abroad. ChinaÆs development has not only improved the living standard of its own people, but also produced a huge market and brought about great opportunities for the world. Since ChinaÆs entry into WTO in 2001, China has imported near to 1.8 trillion usd dollars of goods, averaging a yearly imports of 500 billion usd dollars, creating for other countries and regions more than ten million jobs.   Our prediction is that in the next five years, ChinaÆs imports will be well over three trillion usd dollars. China will continue to serve as one of the leading growth engines for the future world economic development. Now China is on its great strive to achieve the goals of improving living standard for all the Chinese people. We are trying to reach a quadruple gdp of 2000 by the year of 2020, namely to reach gdp four trillion usd, a gdp per capita 3000 usd dollars.

Jan 1, 2005

By K Ellis, B Lumsden

A full-scale statistically-based on/off plant trial of a new flotation conditioning technology designed to improve fine mineral recovery was undertaken to determine whether the recovery of selected fine sulfide minerals can be increased. The technology is selective for certain sulfide minerals only, including chalcopyrite and sphalerite. The technology has been shown to selectively aggregate the fine chalcopyrite and sphalerite minerals giving increased flotation recovery. The plant trials have shown an increase in the mineral recovery, without decreasing selectivity. Size by size recovery shows a significant increase in the fine (

Jan 1, 2005

By A Specht, A Müller, V Montenegro, S Winkler, E Klaffenbach, A Schmidt

In the process of primary copper smelting in flash smelting furnace (FSF), the ratio of iron to silica (Fe/SiO2 mass ratio) primarily determines the slag viscosity and magnetite formation. Viscous slag does not only cause difficulties in daily operation, such as in tapping, it also increases the copper losses to slag. Thus, keeping the Fe/SiO2 mass ratio at the desired level is an important aspect of FSF and slag cleaning furnace (SCF) operation. In this study, the improvement of the Fe/SiO2 mass ratio was conducted in two steps: First, the optimal Fe/SiO2 mass ratio was derived based on thermodynamic data. Based on this analysis, appropriate control limits were determined. Second, this range of favourable Fe/SiO2 mass ratios was implemented into operation by an advice-based control system, which suggests the addition of silica based on the analysis of SCF slag. As this approach was successful, the same advice-based control system principle was adapted for the coke addition to the SCF. After testing the new advice-based control for several months, the production data confirm the predictions by thermodynamics: since the prediction was implemented as an advisor, the copper and magnetite content in SCF slag is significantly reduced and viscous slag is reported less often by operations.

Aug 21, 2024

By D Caffrey

To demonstrate the advantages of using electronic delay detonators over pyrotechnic detonators, a trial using the DNES Dynatronic System was conducted at the KCGM Mount Charlotte operation in 1998. The trial clearly demonstrated that accurate control over the firing delay time between blastholes can lead to fragmentation improvement and ground vibration energy control which are two important issues for the Mt Charlotte underground operation. Excellent fragmentation was achieved by employing a 12 ms delay sequence. Detailed fragmentation analysis has shown a 10 to 20 per cent passing increase for the rock fragment size from 0.1 to 0.4 m compared with the pyrotechnic detonator firing. There was no increase in ground vibration level on the surface with the electronic detonator firing even though the electronic detonator firing had a much shorter blast duration than the pyrotechnic detonator firing. In fact, our energy calculation has clearly shown that much less energy had been propagated to the surface from the blast using electronic detonator firing.

Jan 1, 1999

By G R. Hancock, M J. Saynor, J B. C Lowry, K G. Evans, M Narayan

Tools such as landform evolution models (LEMs) provide a means of predicting how a landform may evolve over extended periods of time. Here, we utilise the CAESAR-Lisflood LEM to assess a proposed rehabilitated landform of the Ranger Uranium Mine in the Northern Territory of Australia (Figure 1). The environmental requirements for the closure of the mine state that the final landform must be able to physically isolate tailings material from the environment for a period of at least 10,000 years (Australian Government, 1999). However, uncertainty exists as to the reliability of model predictions representing thousands of years.In this study, we use model predictions from an undisturbed pre-mine landform to calibrate the parameters used in model simulations of a post-mining rehabilitated landform over a simulated period of 1,000 years. Specifically, we vary environmental conditions such as rainfall, presence/absence of vegetation and surface particle size characteristics in a series of model simulations to determine their impact on the respective landforms, to revise model input parameters as required. A simulated period of 1,000 years was used as it represents a period in which long term landform evolution patterns and trends may be established and identified. CITATION:Lowry, J B C, Narayan, M, Evans, K G, Saynor, M J and Hancock, G R, 2018. Using an undisturbed landform to calibrate long-term predictions of the evolution of a rehabilitated landform, in Proceedings Life-of-Mine 2018, pp 133–137 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By L Smith, R Beckie

An intermediate scale (8 m + 8 m + 5 m high) constructed waste rock pile experiment was built upon a contiguous grid of 16 gravity drainage lysimeters to investigate the flow of water in unsaturated waste rock. Average net infiltration to the uncovered waste rock pile is 55 per cent of precipitation. Large rainfall events have net infiltration of 55 per cent to 85 per cent. Net infiltration estimates range from 23 to 120 per cent of precipitation between lysimeters. Small-scale lysimeters of less than 4 m2 area are shown to be poor predictors of net infiltration for uncovered waste rock. The appropriate size for lysimeters increases with increasing flow rate. The residence time distribution has an estimated median value of 3.0 to 3.9 years under average infiltration conditions. Water flows within the fine grained matrix, within larger pores (macropores), and in matrix free areas of the pile. In situ tracer concentrations vary between pore sizes, and between spatially distinct areas of the pile, indicating water geochemistry may also be variable. Water samples collected from in situ soil water samplers are dominated by the most mobile water fractions. In situ measurements of water content and matric suction are compared to the measured outflow. The data indicate the focusing of flow in spatially distinct areas can make in situ instrumentation a poor (non-conservative) predictor of volumetric water flow.

Jan 1, 2003

By T Ma, F T. Suorineni, Q He, J Oh

Directional hydraulic fracturing was invented by Polish experts and was first applied in coal mining to prevent hard roof rock bursts. Based on its successful application in coal mining, directional hydraulic fracturing has the potential to reorientate the hydraulic fracture trajectory. Recently, this technique has been introduced into cave mining for the purpose of lowering breakdown pressure. The hydraulic fracture is much easier to initiate with the assistance of an initial notch. No systematic theoretical or experimental studies have been carried out to investigate the influencing factors in the hydraulic fracture reorientation process. In this paper, the numerical modelling software Realistic Failure Process Analysis3D (RFPA3D) – Flow Version is used to study the influence of the in situ stress condition and rock mass heterogeneity on directional hydraulic fracturing in brittle heterogeneous rock masses. Firstly, the reliability of RFPA3D in simulating hydraulic fracturing is validated by comparing its results with experimental results and the simulation results from the extended finite element method. The hydraulic fracture trajectory is then observed in a three-dimensional stress environment. The results indicate that for the in situ stress condition, when the borehole lies in the ?2–?3 plane, only the difference between ?2 and ?3 has an important influence on hydraulic fracture reorientation. Furthermore, rock mass heterogeneity is a key factor that must be accounted for when fracture reorientation is required.CITATION:He, Q, Suorineni, F T, Ma, T and Oh, J, 2016. Modelling directional hydraulic fractures in heterogeneous rock masses, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 369–384 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By J Johansson, J Lööw

Attractive mining workplaces are good, safe and healthy environments. They are also workplaces that the workforce of the future wants to work in. As skilled miners and engineers are already scarce, this is important both for today and for the future. However, the future of mining will also be subject to increased international competition. In attempting to become more competitive, many mining companies turn to rationalisation, looking to both rationalise their production and organisation as well as optimise their processes. Work organisation is important in both rationalisation and providing attractive mining work. As a result, this paper investigates a ‘lean production’ (LP) philosophy for the organisation of future mines. The aim of the paper is to investigate to what extent LP can be used to organise for attractive mining. It first defines what attractive mining work is and to what degree it can be influenced by work organisation. A short insight into the LP concept will be given as well as a review of how it is discussed and utilised in mining today. In conclusion, a summary of LP’s potential to realise future attractive mining is given.CITATION:Lööw, J and Johansson, J, 2015. Work organisation for attractive mining – lean mining and the working environment, in Proceedings Third International Future Mining Conference, pp 197–204 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By Brimblecombe P

Morwell Open Cut is a continuous mining operation employing 5 buck- etwheel excavators, I bucket chain excavator and 54 conveyors. The combined bunkering capacity at both client Power Stations represents less than 12 hours maximum coal demand. This creates an extremely dynamic operating environment, which is further complicated with significant variations in both excavating and transportation plant capabilities. To achieve set objectives, including- I adequate reserves, 2 coal supply reliability, 3 cyclic plant maintenance, 4 minimal cost of coal, scheduling of the operation requires constant monitoring and reappraisal. Investigations are in progress to develop a computer based scheduling tool capable of simulating the complex operating environment. A review of computer scheduling packages currently available within the State Electricity Commission of Victoria has found limitations making most unsuitable for the task. The type of package found to be most suited is a knowledge based system ('Expert System')capable of operating within a set of rules defined by the user. Work is proceeding on the development of a knowledge base to test the effectiveness of Personal Computer based `Expert Systems'.

Jan 1, 1989

By Mann LD

The Haveluck gold deposit, located 2.5km north of Meekatharra, contained 1,284,000 tonnes at an average grade of 1.8 g/t gold of drill delineated proved and probable ore prior to commencement of production. Following successful laboratory and pilot scale testing a decision was made to establish a 300,000 tonnes per year heap leaching operation. The ore, crushed to minus 100mm was stacked on an impermeable membrane and irrigated with a dilute cyanide solution. Gold was recovered from the resulting pregnant solutions by adsorption onto activated carbon and gold bullion produced in a modified Zadra process desorption plant. From the commencement of mining it was obvious that a high percentage of fine material was being produced which would adversely affect the percolation of the cyanide solution-through the leach heaps. A screening plant was incorporated into the crushing circuit which provided an oversize product satisfactory for heap leaching and an undersize for carbon-in-pulp treatment. Plant design provided for the slurrying of minus 0.8mm ore before feeding to the pachuca tanks. Initial practice was to use four tanks for gold dissolution and two for carbon contact. Vibrating screens were used through- out for the carbon-ore separation and the loaded carbon was stripped in the existing desorption plant.

Jan 1, 1982

By J Pan, G Qiu

In this paper, an analysis is made of the present situation in the Chinese steel industry and its demand for iron ores. It is shown that the demand for iron ores has been growing substantially with the rapid development of the steel industry all over the world, especially in China. However, the iron ore market is currently in the situation where supply exceeds demand due to the economic crisis, with more investment in mines and less output of steel for several years ahead all over the world. Gigantic pressure is confronting the Chinese steel mills due to the too high and irrational price of iron ores. It is time to return the price of iron ores to a normal position much closer to their value. More attention has therefore been paid to developing low-grade and complex iron ore resources in China due to the irrational price of imported iron ores. More innovative mineral processing processes have been developed to tackle these complex resources. A systematic introduction to the development of beneficiation processes for low-grade iron ores is provided, including upgrading low-grade siderite, limonite, micron sized haematite and magnetite resources.

Jan 1, 2009

By H Zhang, M Karimi, M Hassan, S Saydam, B Li

With the prevalence of Mine Internet of Things (MIoT), different types of sensors have been widely deployed in mine sites for environmental monitoring and operational management. Currently, sensors in mine sites are mainly powered by cables or batteries. However, the deployment and maintenance of a power supply network can be difficult and expensive, and batteries have a limited lifespan. The vibration energy harvesting (VEH) technology can be used to provide power for lowpower sensors in mine sites. This presentation briefly introduces three widely used VEH methods (ie piezoelectric, electromagnetic, and electrostatic). The performance of a commercial electromagnetic energy harvester (ReVibe model D) is evaluated based on the vibration of a lab vibrator (3 g, 50 Hz) and an idling SUV automobile (0.3 g, 25 Hz). Experimental results indicate that a ReVibe energy harvester can generate adequate electricity to power a sensor, and its power output depends on the load resistance as well as the vibration frequency and amplitude of vibration sources. To apply VEH to mining applications, this study also analyses the characteristics of vibration sources at the mine site based on the vibration data collected from various operating machines in a coal handling and preparation plant (CHPP). The vibration analysis results indicate that all the measured vibration sources in the CHPP can generate stable and abundant vibrations, characterised by substantial amplitudes (up to 5.55 g) and low dominant frequencies (ranging from 14 Hz to 25 Hz), which are sufficient for VEH.

Sep 1, 2024

By A Mortazavi, M Akhmedya

Mining is recognised as being one of the most dangerous industries in the world due to the difficult working conditions. Working in such hazardous circumstances in an underground mine often results in a variety of accidents. The working conditions at Kazakhstan’s underground mines have deteriorated owing to a lack of a risk-reduction plan and methodology. This paper evaluates different underground mines in Kazakhstan and demonstrates the employed mining method and the observed failure modes. Risk assessment has long been recognised as a valuable technique for preventing accidents. In the underground mining sector, risk assessment tools play an important role in avoiding work-related accidents. However, geotechnical uncertainty is a significant source of severe incidents like stress-induced roof collapse, wedge failure, seismicity etc, which result in human and financial losses. A geotechnical risk assessment performed early in the mine design process might assist justify a different mine design component, such as different support systems for a dangerous location within the mine openings during mining. The goal of this research is to create a damage/failure database aiming at the development of a geomechanical risk assessment methodology. This work identifies a thematic structure linked to risk assessment and management for the examined Kazakhstan mining sector. As part of the developed database, the dominant modes of failure within the Kazakhstan underground mining conditions were investigated. The study will provide opportunities to establish future research objectives for Kazakhstan’s mining industry where there are significant gaps between state-of-the-art research and mining operations in practice.

Nov 29, 2022

By M A. Harrington-Baker, J M. Trudnowski

Sulfate-reducing bacteria (SRB) have the ability to immobilise dissolved metals by precipitating them as sulfides, provided that a favourable biochemical environment is created. Such an environment includes the presence of sulfate, anaerobic conditions and the availability of organic carbon. If such conditions are engineered within a reactive barrier or field-bioreactor, most metals can be effectively removed. To demonstrate this concept, three passive SRB field-bioreactors were constructed in 1998 at an abandoned mine site in the vicinity of Butte, Montana, USA to treat acid mine drainage with characteristic elevated concentration of metals and low pH. Performance of the field-bioreactors, using aqueous samples, was monitored over 32 months until the project was terminated, field-bioreactors were decommissioned and solid matrix sampling of the reactive matter was performed. The most important analytical results are presented in this paper together with conclusions regarding the appropriateness of the field-bioreactors construction features. Only Zn, Cu, and Cd were being removed as sulfides due to SRB activities. Changes in concentrations of other metals (Fe, Mn, Al, As), which do not necessarily precipitate as sulfide, seemed to be affected by SRB only in an indirect manner by responding to increased pH caused by SRB activity. An innovative cellular containment system used for placing organic matter worked very well in preventing settling of the organic matter and ensuring uniform flow of AMD throughout the entire cross-section of the organic carbon with no preferential flow paths This demonstration was funded by the US EPA and was jointly administered by the EPA and the US DOE under DOE contract number DE-AC22-96EW96405. The project was implemented by MSE Technology Applications, Inc, Butte, Montana, USA.

Jan 1, 2003

This paper investigates the adequacy of current gas monitoring techniques to adequately detect spontaneous combustion in underground coalmines. Despite being in the 21st century spontaneous combustion continues to occur in underground coalmines sometimes being detected only at a very advanced stage. Control of the incident is often then very expensive and time consuming. The adequacy needs to be assessed not only from the point of view of the analysis technique be it tube bundle, gas chromatograph or real time sensor but also the number, location and sampling frequency of the monitoring locations. Recommendations are made to optimise monitoring processes and recognise limitations of current techniques.

Jan 1, 2005