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By N Lefebvre, M Jakeman, R Aseervatham

Semi-arid regions suffer from two afflictions; evaporation may exceed precipitation by multiples of two or more and variations in precipitation can be both extreme and difficult to predict. Many Australian mines are situated in semi-arid areas where communities are reliant upon locally sourced water or special purpose infrastructure is built as part of the mine construction. As the question of climate change looms, issues related to future water supply and sustainable water management become increasingly important. Across Australia several mining operations co-exist in a single surface water and/or groundwater catchment area. The management of water on a mine by mine or a community by community basis is illogical and must be reconsidered based on a single water catchment and a whole-of-community basis. Mine water should be considered on a full life cycle basis where the quality is assessed for specific mine site applications. This paper addresses technical challenges that include surface water and groundwater supply in semi-arid regions, operational water in the mining industry, beneficial uses of water, water economics and demand management. In much the same way as emissions trading evolved into a multi-stakeholder forum, mining regions offer scope for innovative thinking in water supply and reuse. In addition, this paper considers a number of initiatives taken by Australian mining companies that are entering a prefeasibility stage and contrasts these initiatives against the established success within a South African mining region. The challenges and potential solutions to this initiative are presented for future consideration.

Jan 1, 2006

By J deVries, A Broodryk, P Kyselica, K McLean

Gwalia gold mine is located close to the town of Leonora in the Goldfields region of Western Australia, some 830 km from Perth. The mine is wholly owned by St Barbara Ltd, an Australian Securities Exchange listed gold producer and explorer. The Gwalia mine is a deep, all-trucking mine and is serviced by a 10 km long decline from surface. Mining is currently 1540 m below surface. Reserves extend to 1820 m below surface and are open at depth. The mine produces in excess of 200 koz of gold per annum.The Leonora area is hot and arid, with a mean annual rainfall of 230 mm and a 95 per cent mean daily maximum temperature of 20.3°C wet-bulb and 35.6°C dry-bulb.The primary ventilation system comprises a 490 kg/s surface exhaust fan, which draws air down a parallel intake system consisting of the decline, and a dedicated fresh-air intake system extending to the bottom of the production zone. Cooling is provided via a surface bulk air cooler serviced by an ammonia refrigeration plant that delivers 150 kg/s of chilled water to the bulk air cooler.The refrigeration plant and bulk air cooler were installed in 2008. The design allows cooling to be increased over time by installing an additional refrigeration plant in a lead lag configuration with the current refrigeration plant when required.Since 2008, expansion and increased depth reached a point where the underground heat load exceeded the installed capacity of the existing 4.0 megawatt rated (MWR) refrigeration plant. In order to maintain the mine design conditions underground, upgrading of the existing refrigeration system was required to bring the cooling capacity to 7.5 MWR.Two expansion options were considered: the addition of an ammonia vapour-compression refrigeration machine similar to the existing one or a lithium bromide absorption refrigeration system using waste heat from the site power station. The original design and layout of equipment on-site meant that either could be used, allowing an assessment of the merits of both when additional cooling was required.The decision was made to install a lithium bromide absorption system on the lead side of the existing ammonia refrigeration plant. This arrangement provides considerable economic benefits, including reductions in site-generated electrical power, generator fuel consumption and carbon dioxide emissions.This paper details the planning, design, installation and commissioning of the absorption chillers.CITATION:Broodryk, A, deVries, J, Kyselica, P and McLean, K, 2015. The design, installation and commissioning of an absorption refrigeration system at Gwalia gold mine in Western Australia, in Proceedings The Australian Mine Ventilation Conference, pp 193–200 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By Keyte SG

Gravity methods of recovering alluvial gold are not very efficient at particle sizes below about 0.1mm. Whereas such gold may not have been economic to recover in the past, the same may not be true today. Centrifugal concentrators, like the Knudsen and Knelson bowls, are showing promise after an inauspicious start, at least in New Zealand. The large proportion of heavy mineral in many auriferous beach sands and the natural hydrophobicity of fine gold should make flotation an attractive contender for its recovery. The conventional mechanical flotation cell is effective, but roughing, scavenging and cleaning are necessary to achieve both high recovery and low mass yield. More problematic is the difficulty of maintaining coarse and dense sands in suspension. The air sparged hydrocyclone is effective at recovering fine gold from a fine Colarado River sand, but is not effective for the coarse and dense beach sands of New Zealand. The flotation column shows much promise for these sands, when recoveries of over 80% and mass yields of less than 1% can be achieved in a single pass. The froth separator of the USSR and flash flotation could also be worthy contenders. It is felt that flotation could be limited to naturally and artificially de-slimed concentrates.

Jan 1, 1990

By Mutmansky J. M, Organiscak J, Qin J, Bhaskar R

The results of a two-year research study into the relationship between quartz dust levels in host material and in respirable dust in continuous mining sections are presented in this paper. The experimental design and sampling procedures for underground data collection are outlined. The sample analysis procedures for quartz determination, the analysis results and conclusions of the study are discussed.

Jan 1, 1988

The intention of this paper is to examine the practical and technical aspects associated with the measurement of blasting related phenomena. The emphasis is directed towards the acquisition of quantitative data rather than its theoretical interpretation. The application of advanced technologies will require that many more people involved with blasting become familiar with this topic. Against the many other disciplines where measurement may be beneficial, blasting is peculiar on several counts. 1) It must almost always be carried out in the field, and very often in a production environment. 2) Much consideration must be given for the safety of personnel and equipment. 3) The process is dynamic and seldom repeatable. Because the blast process is so dynamic there is little opportunity for direct examination. For this reason measurements are almost universally made using electronic techniques. In this way the event can be captured faithfully as it occurs and later examined in detail, after the fact. It is obvious that some familiarity with these electronic techniques is a necessary ingredient for successful blast monitoring.

Jan 1, 1990

By J Hartnett, B Tarrant, A Rayner, D O’Toole, P Davies

Since 2009, the Northern Territory and Australian governments have been working under a national partnership arrangement to inform a rehabilitation plan for the former Rum Jungle uranium mine. Part of the rehabilitation strategy is to backfill a flooded former pit (Pit), which extends down to 100m below the current pit lake surface and was historically partially backfilled with uranium tailings. It is proposed to utilise the remaining pit volume below water level to sub-aqueously store Potentially Acid Forming (PAF-I) waste rock which currently occupies large stockpiles across the site. The rehabilitation design and planning process undertaken to develop a strategy commensurate to project objectives and construction constraints involved the establishment of key constraints derived from the analysis of historic data sources and preliminary design efforts. Tabled strategies were balanced against dependent project tasks and project objectives, especially surrounding minimising disturbance of highly contaminated materials within the Pit. Ideas were developed in conjunction with industry input and review of case histories to develop a remediation solution that is constructible within the project timeframe and constraints.

Jul 1, 2021

The narrow quartz vein deposits at Konongo and Ghana Main Reef gold mines in Ghana were emplaced during the plastic flow cross folding of pre-existing sub-isoclinally folded volcanic and perivolcanic deposits of Proterozoic age. The older fold structures tightened differentially according to their position in relation to the axes of the cross fold pattern giving complex outlines to the reefs in both plan and cross section.Some 4500 measurements of bedding plane linears were used in the resolution of the Boabedroo footwall structure at Konongo. The methodology developed at the Boabedroo mine was then successfully applied to other complex bodies at the Konongo and Ghana Main Reef mines.All mine development, especially stope preparation, of the folded quartz reefs at Konongo and Ghana Main Reef was controlled by the geologist to ensure that the veins were removed with as few geologically enduced hiccoughs as possible.

Jan 1, 1993

By Fowler T. J

Examples are provided of discontinuity analysis at selected sites in central Victoria. Discontinuities are rock fractures of low tensile strength, including bedding, foliations and joints, which are analysed during rock excavation design, to quantitatively determine the defect orientations, spacing and lengths. Their analysis can reduce the cost of mining operation and improve safety. Extrapolation beyond the exposed face is required, although difficult without an understanding of the regional geology. For rock engineering purposes assumptions are commonly made that discontinuity characteristics are uniform throughout the rock mass, however this is often invalid, as rock masses have usually undergone large-scale deformation, exhibit anisotropy and inhomogeneity. Structural geologists are able to interpret large-scale deformation responses for the purposes of structural correlation and extrapolation. Examples of discontinuity analysis linked to regional geological assesment from sites in central Victoria, reveal that discontinuities exhibit similar characteristics in a range of rock types of different ages and composition. Spacing variations between individual sites are believed to be a result of local rock type differences.

Jan 1, 1997

This paper reviews the developments in understanding of the entrainment mechanism and its modelling in industrial flotation processes over the last 30 years. Both valuable and gangue minerals in the pulp zone of an industrial flotation machine can be transported through the froth zone to the concentrate launder in the water which must also be transferred from the pulp zone to maintain a stable froth zone in conventional flotation. A size dependent portion of each entrained mineral continues in normal circumstances to the concentrate launder. The size dependency arises because the larger particles are able to drain more successfully from the froth region. Gangue minerals are recovered by a number of mechanisms, entrainment being an important one in many cases. The entrainment mechanism is discussed on the basis of the pattern observed in recovery û size data for minerals. Its industrial implications are discussed and means of minimisation of the importance of the mechanism are also discussed. Various means proposed for mathematical modelling of the entrainment mechanism are also described. The effect of process variables on key parameters in these models is reviewed. Properties of both the pulp and froth zones are discussed where needed and means of taking additional measurements with devices developed over the last ten years are discussed as part of the collection of more detailed data on the flotation process in general and the entrainment mechanism in particular.

Jan 1, 2005

By Hall J. S, Zuiderwyk M, Reid A. F

A prototype version of a computer controll- ed on-line scanning electron microscope image analyser, employing the real-time signals ob tamed by digital control of the electron beam has been used to obtain statistical quantificat lion of a wide range of mineral grain character istics, including composition, size distribut- ion, and degree of liberation. These propert lies have been determined for suites of whole particles of flotation concentrates, mounted without further preparation. The facility is also well adapted to the measurement of general Istereological parameters. The computer control software is based on an operating system which includes the device drivers and which is linked to FORTRAN programs [containing the procedural algorithms. The beam scanner provides a 4000 x 4000 point raster swept at a 10 Mhz rate in steps of 1 to 200 points and a set of up to 8 signal channels which respond to electron or energy dispersive X-ray signals to provide a digital attern.characterizing the sample composition. the beam is stepped at high speed until a part- 'cle or phase boundary is encountered; a longer well time is set if X-ray data is required. he digital scanner interrupts the computer

Jan 1, 1977

By K Knorr

Desktop X-ray powder diffraction using a D2 PHASER equipped with fast linear detector was performed on several iron ore and mill scale samples. Data were analysed using cluster analysis and Rietveld quantitative phase analysis. The quantitative mineralogy of both materials could be established. Thus the input is provided for understanding the energy consumption and the CO2 emission during iron production. Furthermore, tabletop XRD allows to distinguish iron ore from mill scales and to quantify their mixtures.

Jul 11, 2011

By T Wang, D Wang

Photogrammetry-based techniques supported by traditional mapping tools are more frequently used for open pit geotechnical mapping. It fundamentally involves the collection of geological, structural and rock mass data from pit batters when safe to do so. These are essential components for refining and implementing continuous improvements to geotechnical models. The geotechnical model is used to review bench performance, optimise geotechnical design parameters, interpretation and analysis of pit slope stability. This paper is a case study of implementing different pit mapping methods at Mount Carlton gold mine, North Queensland. It critically reviews the tools required, including the Brunton compass, mobile application Clino, geotechnical data mapping software CloudCompare (2015) and Sirovision software. The review compares the image precision, structural measurements and data analysis. The review also underlines mine site management philosophy for safe geotechnical data collection to identify in-pit geotechnical hazards and the mitigation of potential slope instability. Sirovision is a remote sensing system for site geology mapping and interpreting geotechnical characteristics of exposed mining faces. The system utilises off-the-shelf digital SLR cameras to capture stereo photographs of the rock face and uses the latest image processing technology to generate accurate 3D models. These 3D models are digitally analysed using computational geometry to extract unbiased and accurate geological and geotechnical data. CloudCompare processes high accuracy 3D dense cloud rock surfaces reconstructed with photogrammetry software to extract the geological planes using the FACET or Compass plugins. The major discontinuity sets can be observed and the orientation (dip/dip direction) obtained from the algorithm is accurate and reliable for geotechnical assessment, including kinematic and rock slope stability analysis.

Nov 29, 2022

By A Karrech, G M. Hassan, A Varghese, E Lessing, S Martins

Pumps play a critical role in mining operations, and their energy consumption and environmental impact are significant. This paper addresses the need for a holistic approach to sustainable pump deployment by expanding on previous work presented at IMPC Asia Pacific 2022 and World Mining Congress 2023. The research takes a significant step forward by outlining a structured approach to estimate and demonstrate sustainability tailored for operational slurry pumps. It details the calculation methodologies used to quantify the carbon dioxide emissions from electricity, wear materials and transport, as well as sealing water usage. To enhance practicality and usability, a simplified visual representation—called sustainability metrics—has been developed to monitor overall efficiency. The sustainability metrics consist of the availability, pump efficiency, and water utilisation efficiency. The proposed methodology is integrated with Pumps Condition Monitoring Service to maximise benefits. Three case studies, from iron ore, copper, and nickel operations globally, were employed to evaluate the proposed methodology. The findings demonstrate the critical role of sustainability calculations in understanding pumps operation. These calculations improve awareness of the pump’s role in the sustainability journey and enable effective monitoring. The studies highlight that continuous monitoring paired with effective prescriptive maintenance strategy can significantly reduce power and water consumption while maximising pump availability. The case studies also reveal significant shortcomings in current operational practices and non-optimal maintenance regimes, emphasising the need for practical recommendations to maximise savings and optimise pump performance. In the context of increasing climate change awareness and the imperative for global decarbonisation, this research highlights the necessity of critically assessing methods and operations to drive sustainability in the mining industry. By adopting a holistic approach to sustainable pump deployment, mining operations can effectively reduce their environmental impact while enhancing operational efficiency and economic viability. The proposed methodology and case studies provide valuable insights and practical recommendations for mining companies seeking to achieve sustainable practices and contribute to a decarbonised future.

Sep 1, 2024

THE area of the State of New South Wales is not great, nevertheless it has very large and important Mineral Resources. This is the more noticeable when the values of the annual mineral production from the individual States of the Commonwealth arecompared with the value of the New South Wales production. The principal minerals mined now are not gold, copper, and tin, as they were in the early years following the gold rush of 1851, the centre of gravity of commercial mineral activity having moved to coal and "oil-shale," water, limestone (with cement), silver-lead-zinc cadmium, sulphur, slate and other building and ornamental stone, road materials, and clays.From small areas totalling only 650 sq. miles, coal to the extent of 311,000,000 tons, valued at £151,000,000, has been won.The estimate of actual and probable reserves by the Mines Department within an area of less than 1000 sq. miles is about 14,000,000,000 tons, while the potential reserves within the remaining 15,500 sq. miles of concealed coal fields must be enormous. Even taking into account only the actual and pI:obable reserves in the 1000 sq. miles known, and assuming a depletion at the rate of 350,000,000 tons a year, or somewhat greater than that of the British Isles at present, and assuming an average value of £1 a ton, with money at 5% compound interest, then the present value of this coal (40 years of depletion) would be £5,575,000,000 approximately: truly an enormous present value for a business of 40 years, dealing only with 1000 sq. miles of country. The location of the main coal basin in New South Wales is one of great strategic importance. It lies almig and near a seaboard, with excellent facilities for anchorage; the coal is of very high quality, and is readily accessible; the climate is admirable. Were this same coal at Port Darwin, its commercial importance would not be be pronounced.

Jan 1, 1926

By R Price

"Technology has the potential to revolutionise industries, work functions or businesses. One such technology in the mining industry is the deployment of automation in a modern autonomous haulage system (AHS). This paper examines a theoretical application of an AHS in a medium scale mine site. The cost-benefit commercial argument is particularly compelling, and the paper outlines metrics and future issues for consideration.Citation:Price, R, 2016. Autonomous Haulage Systems - the Business Case, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 11–17 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By M Laxman, A Kundu

After multiple tailings dam failures in recent times, the owner organisations have made increased efforts to step up the governance systems to industry best practise in the design, construction and operational management areas. The measures include but are not limited to, site investigation, rigorous peer review (both internal and external), certification through appropriately qualified personnel and improvement in operational management practises. While a lot of focus is on design and operational practices, the construction stage requires adaptation (both in terms of materials and approved design) and immediate decision making on site. Work undertaken in these areas is mostly irreversible and sometimes poses serious threat to the future TSF raise/ expansion planning and may lead to reduced life of the TSF and additional risk to the Owner.This technical paper will discuss some challenges and highlight the importance of appropriate processes to achieve a successful construction regime. The process will include a robust quality control/ quality assurance process, a team of designer-constructor-owner with suitable skills and technical understandings and robust documentation of the entire construction process from day 1 to the completion of construction.CITATION:Kundu, A and Laxman, M, 2018. Robust construction and quality assurance culture for tailings storage facilities – equally important as robust design and review practice, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 111–116 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By Neill A, O&apos

The City of Kalgoorlie/Boulder is situated approximately 600 kilometres to the east of Perth (Fig. 1), and is the major regional centre of the Eastern Goldfields, supporting a population of approximately 25,000. The formation of Kalgoorlie Consolidated Gold Mines in 1989 brought the existing operat- ing entities adjacent to the city under common ownership and management. The Joint Venturers forming the management company are Homestake Gold of Australia and Gold Mines of Kalgoorlie (a Normandy/Poseidon com- pany). This traditional underground mining centre has been worked since 1893, yielding 40.8 million ounces of gold from ore with an average head grade of 10 grams per tonne. Historically the heart of the operation has been the famous Golden Mile located on the Eastern perimeter of the city, in the area known as Fimiston. The other significant operations that form KCGM are the Mt Percy Open Pit and the Mt Charlotte Underground Operation. KCGM's current production is 520,000 ounces per year, with the com- bined Fimiston operations (open cut and underground) contributing 400,000 ounces. The current expansion will increase production levels by a further 150,000 ounces. Traditionally 98 per cent of gold has been sourced from underground areas, however the recent upsurge of open cut operations is rapidly overturning this historical relationship.

Jan 1, 1991

The paper describes the 209 in. single stage axial flow mine ventilating fan which commenced operation at The Zinc Corporation Limited, Broken'Hill, N.S.W., in January, 1954.This fan is used to ,ventilate the underground workings of The Zinc Corporation Limited and New Broken Hill Consolidated Limited and, at the time of installation it was the largest fan of its type in the world. It has amaximum capacity of 900,000 c.f.m. at 4·2 in. watergauge and is equipped with adjustable pitch blades and a novel form of variable speed drive.The considerations which lead to the adoption of this particular design are outlined, and a full description of the contruction and installation of the fan and auxiliaries is given.Comprehensive acceptance tests were carried out on the completed installation and, the testing procedure is described in detail. The results of sound level measurements are also included. A brief report on the performance during the 12 month period from 1st July, 1954, to 30th June, 1955, is then given.SELECTION AND DESIGN OF FANGeneral ConsiderationsBecause of the economic advantages of joint ventilation of the underground workings of The Zinc Corporation Limited and New Broken Hill Consolidated Limited, it was decided, after a full review of the future ventilating requirements of both mines, to sink a 20 ft. diameter circular upcast airway on the common boundary of the two properties, to handle a maximum quantity of 900,000 c.f.m.The anticipated air requirements were at this stage estimated to be:(a) initially 700,000 c.f.m. through a mine equivalent orifice of 160 to 2'40 sq. ft. (equivalent total pressures being 2·70 in. w.g. and 1·20 in. w.g.) ;

Jan 1, 1956

An empirical method of estimating dense rock (D.R.E.) equivalent volumes erupted as airfall tephra, described in a companion paper in this volume, is elaborated, and its accuracy discussed. Estimates obtained from a single eruption can be classified as to whether they show positive, negative, or constant relative dispersion. For positively dispersed tephras (estimated volumes increasing with distance), this procedure improves the accuracy of the method. The technique is applied to selected andesitic tephras erupted from Egmont Volcano, New Zealand, during the last 28 000 years, which are found to range in volume from about 1.5 x 107 m3 up to about 2.4 x 108 m3 D.R.E. With a factor of about 16 between the smallest and largest volumes, this contrasts sharply with the rhyolite volcanoes in New Zealand, where the difference factor is usually of the order of 100. The largest tephra eruptions at Egmont are small compared to the largest debris avalanches, which have exceeded 1010 m3 (10 km3) in volume.The magnitude versus frequency relationship, calculated using a maximum likelihood method, establishes the limits of eruption magnitude at Mt Egmont as 107 to 109 m3 D.R.E. For some volcanoes, the magnitude-frequency relationship changes with time, owing to clustering of eruptions, separated by long dormant intervals. Ngauruhoe Volcano, New Zealand, is an example. Within eruptive episodes, the mean interval between eruptions of >_ 105 m3 is about 0.9 ¦ 0.65 years. The mean interval between eruptive episodes in which >_ 106 m3 is erupted, including episodes in which this volume is erupted gradually, is about 25.8 ¦ 6.6 years, and the mean dormant interval between all episodes is about 5.2 ¦ 3.0 years. At present Ngauruhoe is in an unusually prolonged dormant period, 50% longer than any in the historical record, since 1839.

Jan 1, 1990

By Moxon N. T

A series of low shock energy water resistant emlulsion based explosives have been developed by combining inert materials, such as Perlite P500, into the formulation. The material handling, water resistance and explosive properties of these mixtures were determined as a function of inert additive type, density, charge diameter and emulsion base. Of the emulsion bases tested Emulite produced the best and most stable low density mixtures ranging in density from 0.8 to 1.35 g/cm3 producing velocity of detonations (unconfined) ranging from 3000 to 5500 nits. The mixtures could be detonated successfully at these densities at diameters as low as 25mm. Low shock mixtures formed by combining Emulite with Perlite P500 were successfully trailed at the Cadjebut zinc mine in Western Australia. The performance of the explosive, at three densities, was monitored using both continuous and point to point VOD techniques. The fragmentation produced by the blasts were compared by photographic analysis. During this trial the low shock emulsion mixtures were shown to be as effective as the currently used explosives (packaged emulsion) at a significantly reduced cost.

Jan 1, 1990