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By P Kappen, R N. Collins, K M. Spiers

X-ray absorption spectroscopy (XAS) is a synchrotron-only technique used to determine chemical speciation, providing a powerful alternative to most traditional ‘wet chemistry’ and lab-based speciation methods. XAS is an element specific method that can be used to address a variety of systems, ranging from heterogeneous to homogeneous, polycrystalline to amorphous, and solid to liquid. The strength of XAS in identifying and managing chemical species in tailings and mine waste is demonstrated, with the presentation of highly relevant studies into lead, uranium, chromium and arsenic speciation. In each example, waste samples are compared with known standards, allowing an assessment to be made of the quantity of particular chemical species in each.CITATION:Spiers, K M, Collins, R N and Kappen, P, 2015. ‘Forget the wet chemistry’ – how the Australian Synchrotron can help with tailings and mine waste management, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 145–148 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By J Chen

Research conducted into backfill drainage at Mount Isa Mines since 1992 is described. Piping in draining backfilled stopes has been the primary cause of bulkhead failures and emphasis is placed on research into the piping mechanism. Laboratory and in situ tests aimed at understanding the piping mechanism have been conducted and the results are presented. A case history of piping in a draining bench stope fill mass is described and a technique for reducing the potential for bulkhead failures in bench stopes is presented. Hydraulic fill is produced by standard cycloning of tailings and the overflow (reject material) is sent to thickeners prior to placement in the tailings dams. Research into the partial introduction of thickener underflow into the backfill system and its influence on backfill drainage is also described.

Jan 1, 1998

Electronic Detonators have made significant strides over the last few years, both in quality of product and performance in different blast applications. The precision and flexibility of the SMARTDET units provides the mines with a powerful means of controlling blast results, giving both cost and productivity improvements. The SMARTDET Electronic Detonator System, robust and easy to use, has been successfully deployed over the last 18 months in improving mine productivity and creating safer working conditions in both quarrying and long-hole stoping. The key to the improvements has been the precision and flexibility of the electronic timing, and the ability of the mine personnel to grasp the concept quickly and use it effectively.

Jan 1, 1999

By Stanojevic R, McGlinn PJ, Day RA, Levins DM

This paper reports the results of a number of studies that Ansto has carried out for mineral sands companies concerned about low-levels of naturally-occurring radioactivity in their products. Where measured levels of radioactivity have exceeded allowable levels, Ansto has used specialised techniques to identify the source and distribution of the radioactivity and investigated processing strategies to remove the Contamination.

Jan 1, 1993

By G J. Harbort, V Lawson, L Reemeyer

The Jameson Cell is a high intensity flotation device, which utilises induced air from the atmosphere. It was developed jointly by Mount Isa Mines and Professor Graeme Jameson of the University of Newcastle in the 1980s. It is proven to generate fine bubbles, in the order of 300 to 500 ¦m, in a high intensity, high shear and compact zone contained in the downcomer. This aerated mixture exits the downcomer into the pulp zone, which is the quiescent mineral and gangue separation zone. A number of Australian base metal flotation circuits feature a reverse flotation stage at the head of the circuit. Testwork and plant operating data has shown that the use of a Jameson Cell in the prefloat cleaner application has further improved prefloat gangue recovery and selectivity. Operation of a Jameson Cell in a carbonaceous/pyrite prefloat cleaner duty at the Mt Isa copper concentrator increased copper recovery and reduced pyrite in the copper concentrate. Testwork at Zinifex Century Zinc Mine showed a decrease in zinc losses by the utilisation of Jameson Cell prefloat cleaner. Appraisal of a Jameson Cell in a scalping role within the Mt Isa Copper Concentrator indicated significant benefits could be achieved.

Jan 1, 2005

By C Hall, K Williams, B Keogh, S Wong

Cannington mine is a silver lead zinc operation located in north west Queensland. The operation has been in production since 1997. Ore is primarily moved through an underground material handling system comprising of a crusher, conveyor and hoist. The underground crusher and conveyor system were sited in lower grade ore when the mine was first commissioned. As Cannington is now a mature operation, this ore is considered run of mine and stoping progressed into the crusher exclusion zone. As the stoping fronts advanced there was increased damage on the crusher chamber and infrastructure. In response to monitoring data, the crusher monitoring system was significantly upgraded in 2016. The monitoring system included rock mass and infrastructure instrumentation. It improved the understanding of stress impacts and mechanisms driving the damage within the chamber. It allowed the site geotechnical team to respond to changes utilising ground support, mining sequences and increased levels of monitoring. As stoping and damage to the rock mass continued, so did the process of responding to monitoring data. Ultimately, the monitoring system enabled a safe and controlled closure of the chamber. CITATION:Williams, K, Keogh, B, Hall, C and Wong, S, 2018. Monitoring as an input to support and sequence design, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 446–452 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By Iley J. D

The production of zinc from low grade concentrates, particularly those high in iron, has a poor economic return due to a combination of higher concentrate transport costs, increased processing costs and an increased cost for disposal of iron residues. The production of iron-bearing residues from the electrolytic zinc process is also seen as undesirable for both cost and environmental reasons. This paper details the pilot plant testwork conducted at the Pasminco Research Centre in conjunction with Minproc for the production of zinc oxide fume from a high-iron zinc sulphide concentrate from Colquiri in Bolivia. The concentrate is derived from a tailings retreatment operation and has a high iron content (40 - 45 per cent Zn, 14 - 17 per cent Fe) due to the presence of marmatite. Pilot plant trials were conducted using the slag bath reactor at Pasminco Research Centre at rates up to 500 kg/h of pelletised zinc concentrate, using a natural gas/oxygen-enriched air lance. The fume produced averaged 76 per cent Zn at recoveries up to 96 per cent and was recovered in a baghouse after gas cooling. The iron was oxidised into a fayalitic slag that passed the TCLP test (toxicity characteristic leaching procedure) and the sulphur was oxidised to produce a high SO2 gas which would be suitable for sulphuric acid production. The process produces a zinc oxide fume that can replace calcine as a feed for electrolytic zinc plants. The iron reports to a stable slag for disposal, thus eliminating the need for its disposal as jarosite from the leach plant. Only a simple leaching operation on the fume is required as there is no zinc ferrite present.

Jan 1, 1993

By S Latchireddi

Close circuiting autogenous and semi-autogenous mills is an energy efficient way of grinding and a number of operations have utilised this in the design of their comminution circuits. Owing to the large flow of slurry through the mill that results from operating this way the grates and pulp lifters have to be designed to cope. However, the literature has little or no information on how grate and pulp lifter size and design are related to their ability to remove slurry from the mill. Over the last few years the JKMRC has been researching this area and has developed relationships between grate/pulp lifter design and flowrate capacity. At the same time it has determined the major causes of pulp lifter inefficiency and a solution to preventing this inefficiency (the Twin Chamber Pulp Lifter). This paper describes the models that have been developed through this program and uses industrial scale data to illustrate their accuracy. Results from the industrial trials of the Twin Chamber Pulp Lifter are also presented.

Jan 1, 2000

Getting it right is a very profitable outcome. Shareholders would ideally like to see their directors get it right all the time on the major economic decisions. But it is very difficult for mining directors to get it right all the time in such an uncertain environment. Primary decision-makers of companies with significant stakes in the mining industry should get it right much more frequently. The legal measures of evidence (beyond reasonable doubt and on the balance of probabilities) can be used to determine whether grade estimates (a key revenue variable) are realistic. The application of this approach can be far reaching. More frequently correct decision-making would result in more effective allocation of limited resources (capital and labour). In turn, this would result in higher financial returns and a more extensive mining industry.

Jan 1, 1994

By S Bluhm, R Funnell

Creative mine-designs are constantly being applied in the deep platinum mining industry in South Africa. Recently, this has resulted in deep hot mine-designs including room and pillar, bord and pillar or stall and pillar layouts and the use of in-stope trackless mechanisation. In these mines, the ventilation systems use refrigerated air and high fan pressures and as a result ventilation leakage can have a huge impact. Leakage is a serious impediment to cost-effective operation and potential leakage in future projects is a major factor in judging project viability. This paper describes certain mine layouts and quantifies the extent of the leakage. Based on typical field data, a range of seals from ævery poorÆ to ævery goodÆ was defined and used to estimate overall leakage. Within these mine networks the ventilation pressure, temperature and density all vary significantly and with the multiplicity of leakage paths it was necessary to make use of the VUMA-network simulation package. For the examples examined, the leakage was found to be up to 85 per cent for æpoorÆ category seals and up to 50 per cent for ægoodÆ category seals. The total air flow (and refrigeration) requirements grow exponentially with strike distance due to the compounding effects of higher pressure and more leakage paths. It is shown that beyond certain depths and strike distances the leakage will become so great that it will be impossible to operate cost-effectively û even with ægoodÆ seals. Indeed, in these examples the projects were not considered viable in their original format because of the high ventilation-cooling costs and the mine-designs were modified to include footwall drive systems û the cost of which was justified by the reduced strategic risk to operating ineffectiveness due to leakage.

Jan 1, 2005

By J O. Watson, V S. Vutukuri

This paper presents results of an investigation on acoustic emission characteristics of granite, sandstone and rock-like material in the unconfined compression and tensile tests. Both the acoustic emission signature and stress-stain curve are analysed in the experiments.The experimental results show that different acoustic emission characteristics are observed at different stress and deformation stages in unconfined compression and tensile testing. Extensive and unstable acoustic emission changes may be interpreted as indicating failure of the rock.

Jan 1, 1999

By C V. Deutsch

"Geometallurgical variables often cause problems to conventional geostatistical workflows. There are many variables; some are compositional and some are non-additive. They often show: complex multivariate relationships undersampling relative to conventional grade variables unequal sampling; that is, all variables are not available at all data locations.A variety of approaches have been developed over the years, but geostatisticians remain mostly focused on modelling rock types and a few grade variables with an abundance of data. The problems are reviewed and a chained workflow is presented where appropriate techniques are employed in sequence to permit reliable spatial prediction of geometallurgical variables. The spatial models may be used to assess the value of additional data, for prediction of process performance, for improved mine planning and other optimisation tasks. The chained workflow will include data transformations such as ratios and normal scores that make the variables amenable to geostatistical modelling. Data imputation techniques to account for missing values are considered with special consideration to spatial correlation with the available data. Decorrelation techniques such as the principal components, min/max autocorrelation factors and projection pursuit multivariate transformation are employed to manage massively multivariate modelling. Full distribution modelling must be considered to avoid biases in the prediction of non-additive variables. The post-processing of geometallurgical models must be streamlined for robustness and efficiency. The precise workflow varies according to the specific purpose of the study. Guidelines and thoughts on best practice are presented.CITATION:Deutsch, C V, 2013. Geostatistical modelling of geometallurgical variables - problems and solutions, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013, pp 7-16 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 29, 2013

By N F. Glenn, S Thiruchittampalam, B P. Banerjee, S Raval

The determination of shear strength parameters for the spoil material plays a crucial role in the assessment of a dump’s stability; nevertheless, their evaluation necessitates laborious laboratory experiments. In order to address this issue, Simmons and McManus (2004) formulated a framework that serves as a foundation for categorising spoils according to their distinctive shear strength parameters based on observable and tactile characteristics. This framework, previously identified as the ‘BHP Mitsubishi Alliance Coal (BMAC) Spoil Shear Strength Framework’, is now recognised as the ‘CoalSpoil’ framework. The spoil characterisation provided by the CoalSpoil framework offers benefits but is not without limitations. The examination of these attributes in the field is a time-consuming task that demands expertise. Subjectivity arises in the spoil characterisation when attributes straddle the line between two categories, such as delineating matrix-supported and framework-supported fabric structures. To enhance consistency in the spoil characterisation process, minimising human intervention is crucial to mitigate bias, classification errors, and safety risks. This study seeks to achieve this aim by introducing image-assisted and automated methods for spoil characterisation.

Sep 1, 2024

By M Simanjuntak, A M. Supomo

PT Freeport IndonesiaÆs copper/gold operation disposes of approximately 222 000 dry metric tonnes of tailings per day via two thickeners. Reduction of the flocculant dosage rates in each of the tailing thickeners has been achieved with the installation of Clarometers«, modifications to the existing operating DCS control strategy and a change in plant flocculant. This has reduced the flocculant consumption rate in the last twelve months by approximately 20 per cent. It has also highlighted the disparity in the settling rates of the two thickeners. Collaborative efforts between Cytec technical site engineers and Freeport operational personnel have made possible the overall gains achieved in the tailings thickener optimisation.

Jan 1, 2003

By E Yurakov, D J. Ashelford, M I. Slate

The push for increasing coal production rates continues to place increasing demands on mine management to safely and effectively control seam gas. Gas drainage strategies applied vary in both effectiveness and form. Methods employed are a function of assessed risk, gas reservoir characteristics, surface and underground access, budgetary constraints and gas utilisation potential. With the aim of establishing and optimising the effectiveness and efficiency of gas drainage systems, Australian coal miners in cooperation with gas management specialists are embracing the use of gas reservoir simulators and gas emission models. This paper discusses the evolution of gas drainage practices in Australian underground coal mines and the role of gas reservoir assessment methods in optimising gas drainage systems and gas production forecasts.

Jan 1, 2005

By V A. Diemar

The Chatree Gold Project represents a greenfields discovery of metallurgically clean shallow gold mineralisation in a logistically simple terrain. Total Measured, Indicated and Inferred Resources are currently 31 tonnes of gold and 160 tonnes of silver. Gold occurs in an adularia-sericite epithermal system within quartz-calcite-adularia veins, breccias and stockworks. Host rocks are volcanic arc porphyritic latite-trachyte flows, their pyroclastic equivalents and volcaniclastics of upper Permian to upper Triassic age. The mineralisation was deposited in dilated zones during repeated reactivation of pre-existing structures. To-date five mineralised prospects have been defined by drilling with three reaching JORC Code Mineral Resources status. The project is in its definitive feasibility stage and is anticipated to be in construction during 2000.

Jan 1, 1999

By Burks WG, Hughes FE, Muceniekas E, Whitcher IG

The area containing the iron field, recognised by the writers, is part of an uplifted, portion of the 'Western Australian Plateau,' ranging in elevation from about 1,000 feet to about 3000 feet above sea level. The local rock succession is flat-lying or moderately-folded and belongs to the Nullagine Series of Upper (2). Precambrian age. This series forms the Hamersley Rangeland vast portions of the...

Jan 1, 1964

By Clarke B. N

The Olympic mine is currently and development to 1988. The mine practice is, and number of factors. Dam copper-uranium-gold undergoing construction start production in May ventilation design and will be determined by a These include: 1. Mining method and degree of mechanization. 2. Presence of radon emanating material. 3. High virgin rock temperatures at relatively shallow depths. 4. High ambient air temperatures in Summer.

Jan 1, 1988

By Davey P. T, Tsambourakis G

Mineralogical analysis of supergene sulphide ore recovered from areas close to the underground workings at the abandoned Mutooroo (South Australia) mine shows that the original sulphide minerals have undergone substantial alteration. The cause of this alteration is believed to be contact with the highly saline, acidic mine water. The copper is now present as a sulphide that can best be described as a copper- and iron-delicient chalcopyrite, CuxFeyS2, where in most cases x < y. The values of x and y vary from point-to-point within each grain.Leach tests under a variety of conditions show that dissolution of the copper from the supergene sulphide ore can be readily achieved, particularly when compared with the behaviour of Mt Isa chalcopyrite concentrate. For the supergene sulphide ore, an increase in the acidity and the iron(lll) concentration of the leachant re ults in an increase in the rate of copper dissolution.The results are briefly discussed in terms of the experimental in-situ leaching operation at Mutooroo, South Australia.

Jan 1, 1986

By Veal FL

Technological changes in Portland cement manufacturing during past years have reflected changes in the economics and availability of various types of fuel such as coal, fuel oil and natural gas. The industry consumes a sig- nificant quantity of both thermal and electric- al energy. The nature of the process and its chemical constraints does however permit the use of comparatively low grade fuels such as high ash coal and high sulphur oil. In striving for increased daily kiln outputs and conservation of energy, there is a worldwide trend towards the use of dry process plants. Wet process kilns of about 2 500 tonnes per day assume massive component sizes which present difficulties in manufacture, and transport to plant sites. Large capacity dry process units in excess of 8 000 tonnes per day are now in operation using precalcination techniques in which part of the fuel is introduced in the static preheater section ahead of the kiln while the balance is added to the kiln in a conventional manner. This technique has virtually doubled the potential output of any given single kiln.

Jan 1, 1976