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By R Minnitt

Two methods of calibrating the parameters K and Alpha for use in Gy’s formula for the fundamental sampling error were investigated. Approximately 480 kg of broken ore from Harmony’s Target gold mine in South Africa was used to compile the replicate samples for two experiments. The duplicate series analysis (DSA) and segregation free analysis (SFA) methods differ in terms of their approach to recovering the sized materials required for the calibration procedure. In this experiment the DSA method split off six more-or-less equal masses of material from a 75 kg lot that was successively crushed to finer and finer fragment sizes. The sublots so formed were split into 32 samples and fire assayed for gold. The SFA method used approximately 250 kg of broken ore crushed to 95 per cent passing 2.50 cm, which was then passed through successively finer screens until a sublot of less than 0.0075 cm was obtained. Each of the 15 sublots obtained in this way were split using a riffle splitter into 32 samples that were fire assayed. A total of 672 fire assays were used in these experiments. The sampling parameters K and Alpha were used for the compilation of a nomogram and to calculate the gold liberation size of the ores. While there are no definitive results in terms of the actual gold grain sizes against which the calculated sizes can be compared, it appears that the DSA method produces more acceptable results.CITATION:Minnitt, R, 2014. A comparison of two methods for calculating the constants K and alpha in a broken ore, in Proceedings Sampling 2014 , pp 165–178 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 29, 2014

By Kuzmitch O, Morozov A

The main direction in the mechanisation in the mines of the Donbas and the USSR is long-face technology with complexes on the base of hydraulic supports. On the base of the 30 year old experience of exploitation of the coal clearing systems the serious data about the behaviour of the contained rock, display of underground pressure 'on longwalls and preparatory workings have been accumulated. Exploitation works in mines of the USSR are carried out at different depths: from 1000m to 1200m. There are 26 mines in Donbas, which exceed the depth of 1000m. It is the mines of Donbas, where is a rich experience of the exploitation of coal seams in various conditions. Besides, there are wide variations on the factors of the extraction thickness, depth of seam, angle of dip, occurrence of gas dynamics and others. In many scientific establishments, and in Donetsk Polytechnical Institute also, there are scientific research/results, which can be of interest for the coal mining countries.The volume of coal mining from longwall system-mechanised walls in Donbas became stable at the end of the 70s at level of 70 percent. All the efforts to increase this level have not given any notable results, not saying about the technical-economical data, which gradually deteriorate. It shows that positive progress in using the technology for the long walls is over and it is necessary to find new ways of mechanisation of coal winning.

Jan 1, 1991

By H He, S Tillotson, S Gibbons, J Shaw

"Water evaluation and management during mining exploration and operational activities is crucial to minimise direct and indirect operational costs and also in delivering mining companies the less tangible, but equally critical æsocial license to operateÆ.Mining is often carried out in remote areas, where the mine will be the most significant and visible user and potential contaminator of water resources. However, wherever it is located, a mineÆs use of water must be managed in the context of two key aspects: the natural parameters of the resource; its abundance, its temporal variability and its chemical and physical qualities other users of the resource; other industry, potable water supplies and ecological requirements of local habitats.It is vital, therefore, that this commodity be assessed to an appropriate degree to help establish the viability and sustainability of the mining project and identify those other stakeholders who may be affected by the mining companyÆs activities.This paper outlines the background to catchment-scale model and presents a cost-effective method for establishing a robust water baseline and creating a water management tool to be used throughout whole mine life cycle. Numerical surface and groundwater modelling has long been established as a tool for reactive management, following collation of yearsÆ worth of data. Now, using freely available remote sensing data and desk study information, analytical modelling techniques can be used cost effectively to provide mining companies with a tool for assessing and managing their water consumption requirements at the outset of a new project venture.The paper includes a selection of case studies to show how the use of analytical modelling can be used as an evaluation and management tool to help not only assess general watershed parameters and water availability but also how it can be used as a tool to provide decision makers with the information to complete æwhat if?Æ scenario assessments. The case studies illustrate how a combined hydrological and hydrogeological model may enable identification of sensitive receptors, water competition issues and contaminant migration pathways to help manage the risks associated with water consumption and its potential contamination from exploration and operational activities.CITATION:Gibbons, S, Shaw, J, Tillotson, S and He, H, 2013. Catchment-scale water modelling and its role in risk management during mining exploration, in Proceedings Water in Mining 2013, pp 175-188 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 26, 2013

By Firth B. A

The flotation of fine coal (minus 0.5 mm) often requires the addition of an insoluble hydrocarbon collector to apparently promote the adhesion of coal particles to air bubbles. A series of experiments was conducted using a radiotracer and narrow size fractions of clean coal to determine the effect of particle size distribution, collector addition rate, desliming of feed and emuIisification of collector on the distribution of collector between the different size fractions. The concentration of collector per gram of each size fraction was found to be approximately proportional to (average particle size)-2 except if the collector was emulsified prior to addition, the dependence altered to approximately (average particle size)-1. Mechanistic consequences are discussed.

Jan 1, 1982

By Hindmarsh J. W, McCoy A. E R

Instantaneous outbursts of coal and gas have occurred at various times in several working districts of Metropolitan Colliery, N.S.W.They have occurred in headings only, under both hand and mechanised conditions, and with seam gas ranging from mainly methane to nearly pure carbon dioxide. A modification of inducer shotfiring using a shear cut was introduced in 1955, and in 1961 full face firing both to a machine cut shear and off the solid was introduced. The current series of outbursts -1961 to 1963 - has been induced under these systems with full control of the time of outburst, but without prediction, and with some disappointing production features.Various aspects of current conditions and practices at Metropolitan are considered singular, such as the coarse granulometry of outburst coal, the prevalence of floor heave, the absence of strong structures at outburst sites, the possibility of outburst at any stage in pillar formation up to the last few yards, the effect of rate of advance on outburst occurrence, and the mildness of many outbursts experienced.It is concluded that inducer shotfiring is a reliable control but it suffers by comparison with outburst-free conditions, and that control by preyention would be preferable.INTRODUCTIONThe phenomenon of instantaneous outbursts of coal and gas has been described in detail previously (Hargraves, 1958). Briefly, it is a combined gas and stress hazard of deep coal mining, usually occurring in virgin work and during active face advance, when coal and seam gas burst from the face into the workings.Instantaneous outbursts have occurred sporadically at Metropolitan Colliery, N.S.W., since 1895. Early outbursts were recorded as firedamp and recent outbursts are of blackdamp.Mining methods used have been conventional hand work, with progressive and relatively complete mechanisation over the past 25 years to substantially conventional...

Jan 1, 1964

Mr. President, Ladies and Gentlemen, it gives me great pleasure to welcome you, on behalf of the Council and Administration, to this University and extend to you our very best wishes for a most successful and stimulating symposium. We as a College of the University of N.S.W. were always proud of the excellent support we received from your Institute members and the close association that existed between our organisations. Now we have matured into the University of Wollongong and have to stand on our own feet, we will need all the support we can get from such bodies as yours to ensure that we are not only producing graduates but are also playing a vital role in the community. Although there is no planning for a school of Mining Engineering in the near future, we do look forward to this being a viable proposition eventually and we will then be able to offer to your Institute wider facilities for your activities and ones which will embrace both the Mining and Metallurgy phases. Thank you Mr. President.

Jan 1, 1975

By M Ireland

Extensive use of diesel-powered mobile equipment in modern mines for materials handling, such as load-haul-dump machines, constitute a significant source of heat, exhaust gases and diesel particulate matter. Provision of sufficient quantities of fresh, cool air are required to remove such atmospheric contaminants from the environment for miners, particularly at depths where ventilation constraints and associated operating costs have an increasingly adverse impact. An alternative solution to diesel equipment to combat economic, environmental, social and health challenges, are battery electric vehicles (BEV), with the potential to expand production and substantially reduce ventilation and cooling demand, subsequently reducing operating costs. In this context, this paper focuses on the introduction of a battery electric loader to a diesel fleet at one of the deepest underground mines in Australia, the CSA Mine, a high-grade copper operation in Cobar, New South Wales. Analysis of a trial battery electric loader compared to existing diesel machines is performed with regards to infrastructure, technical and operational issues. Key benefits of battery electric vehicles over conventional diesel-powered vehicles are discussed, including lower energy consumption and greater efficiency, reduction of emissions and heat, reduced need for ventilation and lower operating costs. Challenges of introducing BEVs into an operation, along with the results from the comparative study are addressed under impacts to energy consumption, equipment selection, effects on ventilation and cooling, mine design and economic viability for future fleet implementation scenarios whilst meeting production targets.

Mar 29, 2023

By Nageswararao K

A series of tests was carried out on one of the rock-pebble milling circuits treating complex nickel ores at Kambalda Nickel Operations of Western Mining Corporation. A mathematical model to describe the behaviour of a 508 mm hydrocyclone was developed from the data.A "flat" reduced efficiency curve was observed for the system. This was attributed to a marked difference in the specific gravity of different size fractions of the feed. A modified approach in describing the shape or the reduced efficiency curve resulted in accurate prediction of the hydrocyclone performance.

Jan 1, 1981

By W. M. LONIE

Address by the President of the Institute (Mr W M Lonie) in making the presentation of the Certificate of Honorary Membership to Sir Ian McLellan, K.C.G.M, K.B.E. Address by Sir Ian McLellan after accepting the award.

Jan 1, 1979

Experimental investigations were made into the decoppering of lead, tin, and bismuth using a technique which approximates on the small scale to industrial practice.Decoppering lead with sulphur alone in the absence of tin and silver did not proceed to low copper values. With a minimum of 0·02 per cent Ag or 0·10 per cent Sn, lead was decoppered to less than 0·01 per cent Cuby stirring with 0·2 per cent S over 10 min. Decoppering of tin or bismuth proceeded rapidly to very low levels in the absence of any "catalytic" impurities, at any rate in excess of those concentrations normally encountered in commercially pure tin or bismuth.

Jan 1, 1971

By H Susanto, N Belluz, D Flint, A Edw

The Deep Ore Zone (DOZ) is a block cave mining operation exploiting a diluted reserve of 131 million tonnes grading 1.06 per cent copper and 0.81 g/t gold in the lower portion of the Ertsberg East Skarn System (EESS). The EESS is a calcium-magnesium silicate skarn containing in excess of 250 million tonnes of copper-gold ore, located in the Ertsberg Mining District on the crest of the Jawawijaya mountain range in the highlands of Irian Jaya, Indonesia. The EESS was discovered in 1968 where it cropped out at an elevation of 4050 metres above sea level. The Ertsberg Mining District is underlain by siliclastic carbonate and siltstone formations of Jurassic to Tertiary age. The sediments have been folded and are cut by major bedding subparallel and crosscutting structures. Intrusion of a series of igneous bodies post-dates folding and faulting. These I-type intrusions are the source for the copper-gold mineralisation found in the Ertsberg Mining District. The EESS is hosted by carbonates of the Tertiary Waripi and Faumai Formations that have been altered to calcium-magnesium silicate skarn and is situated on the southern limb of a northwest-trending syncline. The EESS is an essentially vertical tabular body with a vertical extent of at least 1200 metres and a lateral extent of up to 1000 metres. The width of the EESS averages 200 metres and locally is in excess of 300 metres. The northeast (hangingwall) contact of the EESS is a skarn reaction front in sudden contact with barren marbles. This contact coincides with a zone of localised faulting and brecciation. The EESS is bounded to the southwest (footwall) by the Ertsberg Diorite, a 3.25 Ma old intrusive. The DOZ block cave operation extends from 3040 metres above sea level to a maximum of 3388 metres above sea level, has a length of 860 metres and a maximum width of 350 metres. The DOZ is a high temperature skarn with a prograde forsterite/diopside mineralogy whose protolith is the dolomitic Tertiary Waripi Formation. The principal retrograde alteration minerals include tremolite, actinolite, serpentine, talc and chlorite. Grade is highest where bornite occurs in large dense complex intergrowths with magnetite and anhydrite. Grade has been locally enhanced in the DOZ by a late-stage pyrite-chalcopyrite hydrothermal alteration event with associated brecciation. Ertsberg Diorite along the footwall of the skarn is also included in the reserve where it is mineralised endoskarn or has been mineralised by porphyrytic or late stage hydrothermal alteration. Formation of the EESS was initiated by contact metamorphism during the intrusion of the Ertsberg Diorite with later metasomatic alteration during both prograde and retrograde phases. The bulk of sulphide mineralisation formed late in the retrograde phase. The EESS is open along strike to the northwest and down-dip with on-going exploration of these areas. Current exploration is targeting both endoskarn and porphyry style alteration and mineralisation of the Ertsberg Diorite.

Jan 1, 1999

By S Speed, N Corlis, A Goldstone, G N. Browne, M Fitzpatrick

In 2005, Solid Energy New Zealand Limited obtained non-notified consent for the disposal of 1Mt of coal ash at the Rotowaro minesite, forming part of a coal supply agreement with the Huntly Power Station. A non-notified resource consent was sought which necessitated that environmental effects be shown to be æless than minorÆ, and resulted from robust science and a pragmatic approach to design. As part of the assessment of environmental effects, there was a need to understand the effects of boron concentrations on aquatic organisms (ie algae, plankton, plants and invertebrates) in the receiving environment. Boron is a naturally occurring element that is found in the form of borates in the oceans, sedimentary rocks, coal, shale, and in some soils but Waikato coals and ashes have particularly high boron content. Boron is an essential micronutrient for higher plants with interspecies differences in the levels required for optimum growth. As aspects of the ANZECC (2000) derived boron limits are based on toxicity of aquatic algae and plants to boron it was important to assess these components in the environment. The effects on the receiving environment of the Awaroa Stream were assessed using predicted water chemistry and comparing actual boron concentrations in a comprehensive and multifaceted reference-condition approach of catchment ecological indicators. In addition a toxicological-based assessment of boron and a re-calculation of the ANZECC trigger levels were undertaken and applied to the ecological indicators. The reference-condition approach revealed that habitat and overall water quality attributes at and between sites was more influential in determining the aquatic biotic communities than boron concentrations alone. There was no evidence of any gradient of changes in ecological indicators with changing boron concentrations, nor evidence of any residual effect of high historic boron concentrations on the aquatic biota.

Jan 1, 2006

By M I. Pownceby, N A. S Webster, R Pattel, N Ware

The decrease in quality of Australian iron ore, coupled with the demand for more efficient energy use, necessitates closer monitoring and optimisation of process conditions for iron ore sinter production. Sinter properties are correlated with the mineralogical content and traditionally, quality control has relied on methods such as Fe2+ determination, point counting via optical microscopy and automated electron beam techniques such as QEMSCAN; these can have a typical turnaround time of several days between sampling and reporting of results. As well, there is additional uncertainty around quantifying some of the complex mineralogical phases in sinter such as silico-ferrite of calcium and aluminium (SFCA) and SFCA-I, which are key phases influencing sinter quality. There is a clear need for the implementation of alternative analytical methodologies that offer a turnaround in hours or even minutes to provide information to accurately maintain production conditions.X-ray diffraction (XRD) is a technique widely used for the quantitative mineralogical phase analysis (QPA) of ores and processed materials in the iron ore industry. Partial least squares regression (PLSR) analysis methods have recently been suggested as an indicator of sinter Fe2+ content from powder XRD data without the need for rigorous and often time-consuming mineralogical analysis by the operator. In this study we provide results from the implementation of PLSR to predict the strength of iron ore sinter. Results are sourced from a well-constrained data set comprising strength properties (as quantified by a tumble index (TI)) from a series of compact laboratory test samples. Using this data set it was determined that PLSR has potential to be used as a method for calculation of sinter TI from powder XRD data and, therefore, process control.CITATION:Webster, N A S, Pownceby, M I, Ware, N and Pattel, R, 2017. Predicting iron ore sinter strength through X-ray diffraction analysis, in Proceedings Iron Ore 2017, pp 331–334 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

It is a sad commentary on human nature that for every successful, unscrupulous entrepreneur you need a multitude of incautious, greedy investors. One wonders whether is will be ever possible to completely protect investors from their reckless gambling instincts, which are so widely encouraged elsewhere in society.

Jan 1, 1989

By T Sylow, A Correa De Araujo, M Gotelip Barbosa

ArcelorMittal is among the largest world’s producers of iron ore. With a geographically diversified portfolio of iron ore and coal assets, it is strategically positioned to serve the network of steel plants, as well as supply the external global market. ArcelorMittal Mining has a global portfolio of 14 iron ore operating units across Brazil, Bosnia, Canada, Kazakhstan, Liberia, Mexico, Ukraine and the United States. Iron ore products include concentrate for sintering and pelletising, pellets, directly shipped fines and lump ore. This paper presents an overview of ArcelorMittal iron ore mines including iron ore typologies and the annual production of each unit. It will also briefly discuss the processing required in order to obtain marketable products.CITATION:Gotelip Barbosa, M, Correa De Araujo, A and Sylow, T, 2017. Overview of ArcelorMittal mining operations and research and development, in Proceedings Iron Ore 2017, pp 161–116 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

This article attempts to outline essential features of the Mount Isa ore deposit, to reveal the agencies thought to be responsible for its localization, and to describe methods used for obtaining and applying geological data on a commercial basis. Structural features are emphasized because they have proved the most useful agencies to date in searching for ore. Vertical depth, horizontal width and stratigraphic thickness are used throughout the article, and quantities are quoted in long tons.THE DEPOSITA width of more than two miles of evenly bedded shale of the Mount Isa series (upper pre-Cambrian) lies sandwiched conformably between quartzites. The series strikes N.S. and dips approximately 60° W. Shale is unaltered...Important geological work has been carried out by the Queensland Geological Survey, chiefly by Mr. S. R. L. Shepherd, in co-operation with the Geological Department of Mount Isa Mines Limited. Selected references are The Queensland Government Mining Journal for December, 1931, January, 1932 (Rio Grande Lode); December, 19B2 (Black Rock Lode); October, 1933 (General structure); October, 1936 (Mount Isa Lode).

Jan 1, 1939

By K Schonert, K Eichas

Electrostatic separation of non-conductive materials can be accomplished by triboelectric charging. The efficiency of convential separators becomes worse in the size range below about 100 ¦m. These problems are solved by developing a new double-drum-separator. The investigations have shown the possibility of separating very fine mineral mixtures (eg quartz/calcite) in a strong electric field after tribo-charging in a special dust-feeder. The paper reports about the influence of particle size and field intensity on the separation and deals furthermore with the problem of desagglomeration.

Jan 1, 1993

By M D. Uttarwar, R R. Yerpude

India is the world’s third-largest producer of coal and is endowed with the fifth-largest coal reserves in the world. Surface mining straddles the entire domain of the Indian coal mining industry, yielding over 88 per cent of production. With continually rising domestic demands, it has to shoulder the responsibility of sustaining the requisite increase in coal production and chasing commensurate stripping targets. Such an ambitious task calls for the deployment of smart technologies. In such a demanding situation, cast blasting of overburden has emerged as a promising alternative for enhancing production and productivity of dragline pits.The cast blasting technique reduces stripping costs significantly as it utilises the chemical energy of explosives in place of mechanical energy to move large volumes of overburden quickly. Proper application of cast blasting not only reduces overall mining costs but also increases coal production. This paper investigates and evaluates the potential of the cast blasting technique, with special reference to dragline pits employing the rehandle method of extended bench. The economic feasibility of the technique is also ensured under different scenarios so that considerable benefits would accrue to the individual surface coalmines. To underline the efficacy of the technique, different cast blasting models have been formulated under a range of operational and economic scenarios that resemble present day practices in India. In order to test for economic variability in the application of the technique, a risk analysis of all the formulated cast blasting models is performed using net present value.CITATION:Uttarwar, M D and Yerpude, R R, 2015. Potential of the overburden cast blasting technique in Indian surface coalmines – a modular approach and its financial implications, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 655–664 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By S J. Schafrik, Z Agioutantis, E C. Jong, K Luxbacher

Real-time monitoring of mine operating parameters is available at most mines. However, access to these data for an individual operation is typically underutilised by mine managers and technical personnel. Such monitoring systems are typically designed to provide data streams and alarms to a responsible person, but they are not utilised to extract underlying trends or correlate different data groups. Furthermore, multiple monitoring systems are usually implemented at a given site without interconnection between vendors’ systems or connection to any central management, and mine personnel are only exposed to a minimal subset of such data. Thus, it is not easy to analyse and correlate individual data streams and generate information to enhance day-to-day operational decision-making and improve safety and efficiency.This paper addresses the primary challenges associated with centralising data management and effecting greater utilisation of the vast amount of collected data, while at the same time reducing the time and effort required to manage such large data sets. Furthermore, it presents the conceptual design of a database application that can organise, present and analyse data collected by multiple sensors in different environments. The database is designed to operate in a passive manner so that active mine data management systems are not impacted. An example is given where this database is used for managing atmospheric data collected at an underground coalmine operation in the US. These techniques have a universal application and can be incorporated in a wide range of mining and construction projects.CITATION:Agioutantis, Z, Schafrik, S J, Jong, E C, Luxbacher, K and Karmis, M, 2015. A platform for managing and analysing atmospheric data in underground coalmines, in Proceedings Third International Future Mining Conference, pp 3–10 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By P To, A Sharp-Paul, S Jones, C Monahan

A key environmental management issue associated with mining projects is tailing disposal. In high rainfall environments this is particularly challenging and generally requires the discharge of excess water from a tailing dam to adjacent streams or coastal waters. Such discharges can potentially have adverse impacts on downstream water quality and the environmental values associated with these waters, such as providing a drinking water supply for local villagers, maintaining a fisheries resource or protecting a fish species of high conservation significance. An alternative to the construction and operation of a conventional tailing dam is Deep Sea Tailing Placement (DSTP). The key features of such a system are:Discharge of the tailing slurry at considerable depth (approximately 120 - 150 m) below the oceanÆs surface. This requires a pipeline to be laid from the process plant to a mix tank, where the tailing is mixed with seawater and entrained air released. The pipeline then continues down the ocean floor to the required discharge depth, which is below the surface mixed layer and the euphotic zone. After discharge, formation of a density current which continues to descend along the ocean floor as long as the slope is sufficiently steep. Final deposition of the tailing in an area where the slope of the ocean floor is insufficient to maintain the density current. This typically occurs at depths of more than 800 m. Water quality issues associated with DSTP include: Impacts on the oceanic water column due to the formation of subsurface plumes which break away from the descending density current. The occurrence of elevated concentrations of contaminants in the interstitial waters of the deposited tailing solids. Fluxes of contaminants from the tailing deposits into the overlying oceanic water column. This paper discusses the water quality aspects of DSTP with particular reference to a case study in Papua New Guinea. The evaluations undertaken as part of the DSTP impact assessment included consideration of both the short- and long-term chemical behaviour of contaminants and bioassays, within the appropriate water quality assessment framework.

Jan 1, 1999